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Wyszukujesz frazę "Singh, S. R." wg kryterium: Autor


Tytuł:
Reverse logistic model for deteriorating item with preservation technology investment and learning effect in an inflationary environment
Autorzy:
Singh, S. R.
Rathore, H.
Powiązania:
https://bibliotekanauki.pl/articles/205799.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
reverse logistics
deterioration
preservation technology
learning
inflation
Opis:
Recycling is essential for the existence of the environment. Nowadays, recycling is also being promoted by the governments of numerous countries in the world. In the recycling process, the used items are collected from the customers and sent back to the remanufacturing unit. In the literature, many authors have assumed that the remanufactured items are as good as the freshly produced ones, but this is not really practical. The remanufactured items are of lower quality than the freshly produced ones. For purposes of studying the recycling process we have developed a reverse logistic model for the deteriorating items. The deterioration rate is treated as a controllable variable, which is controlled by investing in preservation technology. The demand rate is taken as exponential function of time with demand dependent manufacturing and remanufacturing rates. The fresh products are sold in the primary market and the remanufactured products are sold in the secondary market at a low selling price, in view of the low quality of remanufactured products. The whole study is carried out under the effect of learning in an inflationary environment and the learning coefficients are associated with production cost and set-up cost. The main objective of this study is to find the optimal cost value and the optimal operating times. At the end of this article numerical illustration is presented and sensitivity analysis is performed. The whole of the mathematical calculations is done with the use of the mathematical software Mathematica7.
Źródło:
Control and Cybernetics; 2016, 45, 1; 83-94
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A collaborative strategy for a three echelon supply chain with ramp type demand, deterioration and inflation
Autorzy:
Singh, N.
Vaish, B.
Singh, S. R.
Powiązania:
https://bibliotekanauki.pl/articles/406653.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
three echelon supply chain
ramp type demand
deterioration
backlogging
inflation
Opis:
A supply chain system has been investigated in which a single manufacturer procures raw materials from a single supplier, processes them to produce finished products, and then delivers the products to a single retailer. The customer’s demand rate is assumed to be time-sensitive in nature (ramp type) that allows two-phase variation in the demand and production rate. Our adoption of ramp type demand reflects a real market demand for a newly launched product. Shortages are allowed with partial backlogging of demand (only for the retailer), i.e. the rest represent lost sales. The effects of inflation of the cost parameters and deterioration are also considered separately. We show that the total cost function is convex. Using this convexity, a simple algorithm is presented to determine the optimal order quantity and optimal cycle time for the total cost function. The results are discussed with numerical examples and particular cases of the model discussed briefly. A sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out.
Źródło:
Operations Research and Decisions; 2014, 24, 3; 78-100
2081-8858
2391-6060
Pojawia się w:
Operations Research and Decisions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A three level integrated inventory model with time dependent demand and production rate under a trade credit policy for both distributor and retailer
Autorzy:
Singh, N.
Vaish, B.
Singh, S. R.
Powiązania:
https://bibliotekanauki.pl/articles/206192.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
time dependent demand
variable production rate
three echelon supply chain
trade credit
Opis:
This paper develops a three echelon supply chain inventory model with permissible delay in payment, in which distributor and retailer’s demand is time dependent and production rate for manufacturer is also time sensitive. The models consider the two level trade credit policy in manufacturer-distributor and distributor-retailer relationship in this supply chain model. A simple solution algorithm is presented to determine the optimal order quantity and optimal cycle time of the total cost function and the number of shipments for distributor and retailer. The results are discussed with numerical examples and the particular cases of the model are also discussed in brief.
Źródło:
Control and Cybernetics; 2014, 43, 3; 439-469
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of demand boosting policy on optimal inventory policy for imperfect lot size with backorder in fuzzy environment
Autorzy:
Yadav, D.
Singh, S. R.
Kumari, R.
Powiązania:
https://bibliotekanauki.pl/articles/206244.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
learning curve
advertisement
signed distance
triangular fuzzy number
backorder
inventory model
Opis:
This paper investigates an Economic Order Quantity (EOQ) model with backorder by taking imprecise demand rate with dependence upon the frequency of advertisement. The formulated model also incorporates learning effects on percentage of defective items present in each lot. Due to imprecision in demand, the obtained profit function is fuzzy. To determine the optimal values, we determine the equivalent crisp profit function by applying the signed distance method. Optimal order quantity and backorder level are obtained by using algebraic method in place of differential calculus. A numerical example is used to study the behavior of the model with respect to different inventory parameters. All calculations are performed with MATLAB 7.4.
Źródło:
Control and Cybernetics; 2012, 41, 1; 191-212
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inventory models with multiple production and remanufacturing batches under shortages
Autorzy:
Singh, S. R.
Sharma, S.
Kumar, M.
Powiązania:
https://bibliotekanauki.pl/articles/206729.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
inventory models
production
remanufacturing
shortages
Opis:
Owing to the ecological requirements and regulations, an enormous concern is being paid to the product re-processing. In the established literature, researchers considered that the remanufactured items are as good as the new ones. Yet, such an assumption is not convenient, as in many real situations the recycled products are considered by the customers to be of secondary quality. Further, the classical studies mainly addressed the inventory models without shortages, and this is not applicable in many practical business situations. This paper extends the reverse logistics inventory models with finite production and remanufacturing rate along with the assumption that newly produced and repaired (remanufactured) objects are not of same characteristics. Shortages are allowed and numerous stock-out cases are discussed. The collected used items are remanufactured (repaired) and non-repaired products are disposed off. The proposed models are illustrated with some numerical examples and their results are discussed.
Źródło:
Control and Cybernetics; 2016, 45, 3; 385-416
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efficient soil solarization for weed control in the rain-fed upland rice ecosystem
Autorzy:
Khan, A.R.
Srivastava, R.C.
Ghorai, A.K.
Singh, S.R.
Powiązania:
https://bibliotekanauki.pl/articles/25142.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
environment
soil
ground water
weed competition
crop yield
herbicide
solarization
ecosystem
rainfed upland
weed control
toxic residue
rice
Źródło:
International Agrophysics; 2003, 17, 3
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Documentation of tribal’s traditional knowledge of medicinal plants from Renlagadda Thanda, Kodangal mandal, Mahabubnagar Dist, Telangana, India
Autorzy:
Shivakumar Singh, P.
Rajender Singh, D.S.R.
Powiązania:
https://bibliotekanauki.pl/articles/11807.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Opis:
The aim of this report is giving the importance in need of ground leveal documentation of medicinal plants, their ingrediants and usage. To be effort has been made to evaluate plants used for medicare by the tribal people of Renla Gadda Thanda, Kodangal mandal, Mahabubnagar Dist, Telangana. Due to be deficient in of modern healthcare facilities and poor economic conditions, the tribal people of the Thanda fully depend on in the vicinity available medicinal plants for their healthcare needs. In the present report a total of 24 ethnomedicinal plants from 23 genus and 24 species occupied 18 families were recorded. The thorough information i.e., Usage, to be treated disorder, Parts used recorded. This is a first report from the Renlagadda Thanda of Kodangal mandal. The study area having wealthy in medicinal plants flora and tribal communities with latest usages. Documentation of traditional knowledge on medicinal plants from the village or thanda level is the elementary and necessary samples for novel medication.
Źródło:
International Letters of Natural Sciences; 2015, 08
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Temperature on Non-Destructive Wave Propagation in Uranium Monopnictides
Autorzy:
Singh, R.
Singh, M.
Chaurasia, S.
Powiązania:
https://bibliotekanauki.pl/articles/1808103.pdf
Data publikacji:
2009-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.35.Cg
62.20.de
62.20.D-
Opis:
Acoustic attenuation due to phonon-phonon interaction, thermoelastic mechanism and dislocation damping were evaluated in uranium monopnictides (viz. UN, UAs and USb) in the temperature range 50-500 K, along the three crystallographic directions of propagation, viz. [100], [110] and [111] for longitudinal and shear modes of propagation. Due to antiferromagnetic property of these compounds ultrasonic attenuation due to magnon-phonon interaction was also obtained. The second- and third-order elastic moduli of B1-type uranium monopnictides were obtained using electrostatic and the Born repulsive potentials. Gruneisen numbers and acoustic coupling constants were evaluated for longitudinal and shear waves along different directions of propagation and polarization. Results were discussed and compared with available data. It was found that the temperature dependence of attenuation due to phonon-phonon interaction and thermoelastic loss mechanisms follow the third and fourth order polynomial fit laws, respectively, and acoustic attenuation is mainly governed by phonon-phonon interaction in this temperature range.
Źródło:
Acta Physica Polonica A; 2009, 115, 3; 664-670
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dielectric and Ac Conductivity Studies of Mn-Doped $Na_{1.86}Li_{0.10}K_{0.04}Ti_3O_7$ Ceramics
Autorzy:
Singh, R.
Shripal, S.
Powiązania:
https://bibliotekanauki.pl/articles/1206481.pdf
Data publikacji:
2014-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
72.10.Bg
72.20.Ee
72.60.+g
77.22.-d
77.22.Gm
77.22.Jp
Opis:
Dielectric-spectroscopic and ac conductivity studies on 0.01 and 1.0 molar percentage manganese doped layered $Na_{1.86}Li_{0.10}K_{0.04}Ti_3O_7$ ceramics have been reported. The dependence of loss tangent (tan δ) and relative permittivity ($ε_{r}$) on temperature in the range 350-775 K and on frequency in the range 10 kHz-1 MHz have been undertaken. The losses are the characteristics of dipole mechanism, electrical conduction and space charge polarization. The obtained conductivity plots between log($σ_{ac}T$) versus 1000/T have been divided into four regions namely region I, II, III, and IV. The mechanism of conduction in region I is acknowledged to electronic hopping conduction. The less frequency and more temperature dependent region II is ascribed as a mixed mechanism "associated interlayer ionic conduction, electron hopping, and alkali ion hopping conduction". The unassociated interlayer ionic conduction along with alkali ion hopping conduction mechanisms are contributing to the transport process in the mid temperature region III. The mechanism of conduction in the highest temperature region IV may be recognized as the modified interlayer ionic conduction. The conductivity versus frequency curves lead to conclude that the electronic hopping conduction diminishes with the rise of temperature.
Źródło:
Acta Physica Polonica A; 2014, 125, 1; 67-72
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oncology research output and its citation analysis at continental level: a study (2003-2012)
Autorzy:
Pandita, R.
Singh, S.
Powiązania:
https://bibliotekanauki.pl/articles/10898.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
oncological research
citation analysis
continental level
2003-2012 period
Africa
Asia
Europe
North America
South America
medical science
tumour
human disease
treatment
Opis:
The present study examines the research output and citation analysis in the field of Oncology, a branch of medical science which deals with the study and treatment of tumours, what we commonly know as cancer. Cancer as a disease is not confined to a particular region or a country, but is a global phenomenon and is still beyond the complete understanding and control of medicos. Research in the field of biomedical sciences in general and oncology is particular is undertaken at global level with almost each country contributing its bit in understating and control of disease. The study makes an empirical assessment of the research output and growth in the field of oncology at continental level for the period 2003-2012 and evaluates the aspects like research growth, citation analysis, h-Index etc. Data for the present study has been retrieved from the SCImago Journal and Country Ranking, which is totally based on the SCOPUS data source. Findings: - A total of 310593 research papers were published across six continents of the world during the period 2003-2012. Europe emerged the largest continent with its publication share of (124598, 40.11 %). Europe is followed by North America with its share percentage of (102897, 33.12 %) and Asia with (70555, 22.71 %). The contribution of Oceania, South America & Africa to the world oncology research is not that encouraging, as such there is greater need to promote oncology research in these continents. African contribution to global oncology research during the period remained (2215, 0.71 %), South American (3009, 0.96 %) and Oceania contributed (7319, 2.35 %). Oncology research publication on average during the period of study grew annually at 8.15 %, while as at continental level Africa registered highest annual publication growth of 19.08 %. North America and Europe are the only continents which recorded publication's growth below the average global growth.
Źródło:
International Letters of Natural Sciences; 2014, 12, 2
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cancer therapeutics strategy using nano-carrier mediated natural drugs
Autorzy:
Shaw, S.
Singh, P.
Mishra, R.
Singh, R.
Nayak, R.
Bose, S.
Powiązania:
https://bibliotekanauki.pl/articles/2201053.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
breast cancer
porous silicon nanocarrier
quercetin
nucleolin
targeted therapy
rak piersi
krzem porowaty
nanonośniki
kwercetyna
terapia celowana
Opis:
Purpose Nucleolin is a multifactorial protein, having a significant role in chromatin remodelling, mRNA stability, ribosome biogenesis, stemness, angiogenesis, etc., thus, it is potential therapeutic target in cancer. The purpose of this paper is to study porous silicon (pSi) nanocarrier-based natural drug delivery system targeting dysregulated nucleolin expression for cancer therapeutics. Design/methodology/approach Quercetin was loaded in pre-synthesized and characterized pSi nanoparticles, and release kinetics was studied. The study compared the inhibitory concentration (IC50) of quercetin, synthetic drug doxorubicin, and quercetin-loaded pSi nanoparticles. Further, mRNA expression of a target gene, nucleolin, was tested with a quercetin treated breast cancer cell line (MCF-7). Findings Quercetin-loaded pSi nanoparticles followed first-order release kinetics. IC50 was determined at concentrations of 312 nM, 160 µM, and 50 µM against doxorubicin, quercetin, and quercetin-loaded pSi nanoparticles, respectively. The results further indicated 16-fold downregulation of nucleolin mRNA expression after 48h of quercetin treatment of exponentially growing MCF-7 cells. Research limitations/implications Whether pSi nanoparticle loaded quercetin can significantly downregulate nucleolin protein expression and its impact on apoptosis, cell proliferation, and angiogenic pathways need further investigation. Practical implications The practical application of the proposed nanocarrier-based drug delivery system potentially lays out a path for developing targeted therapy against nucleolin-dysregulated cancer using natural products to minimize the side effects of conventional chemotherapeutic drugs. Originality/value Inhibition of nucleolin and nucleolin regulated pathways using natural compounds and its targeted delivery with nanocarrier is not yet done.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2022, 114, 1; 32--41
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trends Analysis of Wind in Srinagar Garhwal Valley, Uttarakhand, India
Autorzy:
Singh, Santosh
Negi, R. S.
Powiązania:
https://bibliotekanauki.pl/articles/1075718.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
AWS
Srinagar Garhwal
Wind Direction
Wind Speed
Opis:
Wind results from the air in motion. Air in motion arises from a pressure gradient. Wind direction and wind speed are two characteristics of the wind, whose inter-relationships may give us an insight into the prevailing weather condition at a particular place. This study examines the trend analysis of the wind direction and wind speed pattern of Srinagar Garhwal Valley, Uttarakhand. The average wind speed in Srinagar Valley is 2.923± 1.232 m/s. As it is seen the most frequent wind in Srinagar Garhwal has a speed from 0.50 to 2.10 m/s in the northwest direction.
Źródło:
World Scientific News; 2019, 119; 248-253
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genetic variability, inheritance and correlation for mineral contents in cabbage (Brassica oleracea var. capitata L.)
Autorzy:
Singh, B.K.
Sharma, S.R.
Singh, B.
Powiązania:
https://bibliotekanauki.pl/articles/2100.pdf
Data publikacji:
2013
Wydawca:
Instytut Ogrodnictwa
Tematy:
cabbage
Brassica oleracea var.capitata
genetic variability
inheritance
mineral content
dietary mineral
iron
zinc
copper
manganese
potassium
calcium
heritability
Źródło:
Journal of Horticultural Research; 2013, 21, 1
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ultrasonic Attenuation in Alloys
Autorzy:
Kor, S. K.
Singh, R. K.
Powiązania:
https://bibliotekanauki.pl/articles/1929339.pdf
Data publikacji:
1993-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.Dc
62.65.+k
Opis:
Ultrasonic attenuation was evaluated in metallic alloys, Ni$\text{}_{x}$Cu$\text{}_{1-x}$ (x = 1.00, 0.70, 0.60, 0.45 and 0) due to phonon-phonon (p-p) interaction and thermoelastic loss in a wide temperature region along ⟨110⟩ crystallographic direction for longitudinal and shear waves. Ultrasonic Grüneisen parameters, nonlinearity constants and ultrasonic attenuation due to p-p interaction and thermoelastic loss were determined from 50 K to 500 K using the Born-Mayer and electrostatic potentials. The results were compared with available experimental results.
Źródło:
Acta Physica Polonica A; 1993, 83, 6; 751-758
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Conservation of the endangered medicinal plant Picrorhiza kurroa through in vitro multiple shoot regeneration
Autorzy:
Chaudhary, V.
Singh, S.
Sharma, R.
Singh, A.
Sharma, N.
Powiązania:
https://bibliotekanauki.pl/articles/80933.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
medicinal plant
Picrorhiza kurroa
endangered plant
shoot regeneration
micropropagation
conservation
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2019, 100, 3
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
TBI Calculations of the Elastic Properties and Structural Phase Transformation in Novel Materials: Yttrium Nitride
Autorzy:
Singh, S.
Chauhan, R.
Gour, A.
Powiązania:
https://bibliotekanauki.pl/articles/1492770.pdf
Data publikacji:
2011-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
64.70.K-
62.20.de
62.50.-p
Opis:
We have carried out high pressure theoretical structural studies of yttrium nitride to examine the phase transition phenomena from the NaCl structure to CsCl structure by using a three-body potential model. The phase transition pressure (140 GPa) predicted by this approach is close to the phase transition pressure, predicted by others (138 GPa). Yttrium nitride is a novel and less explored material. Under high pressure yttrium nitride goes through a sudden collapse in volume showing the first order phase transition. To understand the effect of pressure we studied bulk properties, elastic constants and their combination. The pressure volume equation of state provides meaningful signatures of physical and chemical phenomena under high pressure. Moreover we have successfully checked the stability criterion for this compound.
Źródło:
Acta Physica Polonica A; 2011, 120, 6; 1021-1025
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ultrasonic Attenuation in Dielectric Crystals
Autorzy:
Kor, S. K.
Singh, R. K.
Powiązania:
https://bibliotekanauki.pl/articles/1891964.pdf
Data publikacji:
1991-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.Dc
62.65.+K
Opis:
Ultrasonic attenuation and non-linearity parameters have been evaluated for dielectric crystals RbCl, RbBr and RbI in a wide temperature range. Basic physical parameters, nearest neighbour distance and hardness parameters of the substance and Coulomb and Born-Mayer potentials have been used to obtain ultrasonic attenuation due to phonon-viscosity mechanism along (100) direction of propagation for longitudinal and shear waves. Results are as expected and it has been concluded that ultrasonic attenuation is a fundamental property of the substance.
Źródło:
Acta Physica Polonica A; 1991, 80, 6; 805-810
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intranasal (IN) COVID-19 vaccines - a breakthrough
Autorzy:
Gambhir, R.S.
Kaur, K.
Matariya, R.
Singh, B.
Sood, R.
Singh, J.
Powiązania:
https://bibliotekanauki.pl/articles/28765534.pdf
Data publikacji:
2023
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Opis:
Emerging variants of COVID-19 have threatened the effectiveness of intramuscular (IM) vaccines since that are made to target only the spike protein. Development of Intranasal (IN) vaccination has been proven to provide both the mucosal and systemic immune responses for broader and long lasting protection. Many IN vaccine candidates (virus-vectored vaccines, recombinant subunit vaccines and live attenuated vaccines) are in different phases of clinical trials and in near future many companies would be releasing their vaccines into the drug market. Potential advantages of IN vaccination over IM vaccination makes them ideal to be administered in children and developing populations of the world. This paper focuses on the very recent developments in intranasal vaccination with a spotlight on their safety and efficacy concerns. IN vaccination can prove to be game-changer in handling COVID-19 and potential viral contagious diseases in future.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2023, 74, 1; 15-18
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance Comparison of Protection Strategies in WDM Mesh Networks
Autorzy:
Singh, H. K.
Aggarwal, S.
Singh, S.
Mohapatra, B.
Nagaria, R. K.
Tiwari, S.
Powiązania:
https://bibliotekanauki.pl/articles/308073.pdf
Data publikacji:
2010
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
blocking probability
protection
survivability
switching time
WDM networks
Opis:
Recent development in optical networking employing wavelength division multiplexing (WDM) fulfills the high bandwidth demand applications. Failure of such networks, leads to enormous data and revenue loss. Protection is one of the key techniques, which is used in designing survivable WDM networks. In this paper we compare dedicated and shared protection strategies employed inWDMmesh networks to protect optical networks failure, particularly fiber failure. Dijkstra's shortest path algorithm is considered for carrying out simulations. The paper compares the performance of protection schemes, such as, dedicated path protection (DPP), shared path protection (SPP) and shared link protection (SLP) schemes. Capacity utilization, switching time and blocking probability are the parameters considered to measure the performance of the protection schemes. Simulation results show that, SPP is more efficient in terms of capacity utilization over DPP and SLP schemes, whereas, SLP offered better switching time than both DPP and SPP schemes. The average call drop rate is minimum for shared path protection scheme and maximum for shared link protection scheme.
Źródło:
Journal of Telecommunications and Information Technology; 2010, 1; 62-69
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bioremediation of melanoidin contamination in distillery effluent using Aspergillus brasiliensis
Autorzy:
Singh, T.A.
Singh, T.
Singh, R.
Pandey, P.K.
Gaur, R.
Jamal, F.
Patel, S.K.
Bansal, S.
Powiązania:
https://bibliotekanauki.pl/articles/2097092.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
spent wash
effluent
melanoidin
bioremediation
decolorization
Opis:
The current investigation is the first report of utilization of Aspergillus brasiliensis for the decolorization of melanoidin in distillery effluent. The effluent generated from alcohol distilleries is one of the most complex wastewater with a high biological oxygen demand (BOD) and other organic, inorganic, and toxic constituents. The effluent contains melanoidin, a dark brown compound, which is difficult to remediate by using conventional technologies. The disposal of spent wash in the natural environment is hazardous and can deteriorate land and water resources. The decolorization of spent wash through physical and chemical methods remains unsuitable, and the only alternative to decolorize spent wash is biological treatment. In the current study, three fungal strains were isolated from the distillery waste and screened for their ability to decolorize melanoidin.The isolate RS2 exhibited maximum decolorization of 83% and was identified as Aspergillus brasiliensis. Its optimum growth temperature was 37EC, and the maximum efficiency was recorded after 120 h of incubation. Nutritional sources were investigated for the fungi showing the maximum decolorization of melanoidin, and starch and peptone were found to be the best carbon and nitrogen sources, respectively. At 1.5% starch concentration and 1.5% peptone concentration, the decolorization level attained was 87.45% and 88.74%, respectively. A. brasiliensis exhibited a high potential to decolorize melanoidin. The decolorization percentage was high, which makes this fungus a potential candidate for use at the industrial scale for the bioremediation of spent wash.
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2020, 101, 3; 205-213
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of phytochemical constituents and antioxidant potential of hydro-alcoholic and aqueous extracts of Murraya koenigii L. and Ficus carica L.
Autorzy:
Farooq, S.A.
Singh, R.
Saini, V.
Powiązania:
https://bibliotekanauki.pl/articles/2048978.pdf
Data publikacji:
2019
Wydawca:
Instytut Włókien Naturalnych i Roślin Zielarskich
Tematy:
antioxidant activity
Ficus carica
Murraya koenigii
aktywność antyoksydacyjna
Opis:
Introduction: Murraya koenigii L. and Ficus carica L. have been traditionally used in folk medicine for treating several diseases. Objective: The present study was proposed to investigate the phytochemical constituents and antioxidant potential of hydro-alcoholic and aqueous extracts of leaves of M. koenigii and dried fruits of F. carica. Methods: Phytochemical screening was performed using different methods and antioxidant activity was evaluated by measuring total phenolic content, total antioxidant capacity (TAOC), hydrogen peroxide (H2O2) scavenging activity, DPPH radical-scavenging activity, reducing power assay, nitric oxide radical scavenging activity, and superoxide radical-scavenging activity. Results: The results showed that the hydro-alcoholic and aqueous extracts of leaves of M. koenigii and dried fruits of F. carica possess a significant quantity of flavonoids, saponins, terpenoids (9.0%, 0.9%, 0.6% and 7.3%, 8.7%, 0.44%, respectively) and also possess a significant antioxidant activity as evaluated by employing different antioxidant assays. Conclusion: It may be concluded that the hydro-alcoholic and aqueous extracts of leaves of M. koenigii and dried fruits of F. carica exhibit significant antioxidant activity.
Źródło:
Herba Polonica; 2019, 65, 4; 7-17
0018-0599
Pojawia się w:
Herba Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parametric studies and simulation of PSA process for oxygen production from air
Autorzy:
Beeyani, A.
Singh, K.
Vyas, R.
Kumar, S.
Powiązania:
https://bibliotekanauki.pl/articles/779567.pdf
Data publikacji:
2010
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
amplituda ciśnienia adsorpcji
model matematyczny
symulacja
produkcji tlenu
MATLAB
Zeolit5A
pressure swing adsorption
mathematical model
simulation
oxygen production
Zeolite 5A
Opis:
A numerical simulation and parametric studies for the separation of air using 5A zeolite for the production of oxygen are presented for a basic two bed pressure swing adsorption (PSA) process. The simulation is based on an in-house program 'PSASOL' developed in MATLABŽ. The transient process of PSA has been described by a set of partial differential equations, which were solved using a finite difference method. Simulation results have been validated with the experimental data from literature. Based on the simulation results, an optimal set of operational parameter values has been obtained for the PSA bed. The values of the optimal parameters, viz. adsorption pressure, cycle time, feed rate, and product rate have been found to be 2.5 atm, 150 s, 15 cm3/s, and 2.55 cm3/s, respectively. For the optimal conditions, purity of 95.45% and recovery of 77.3% have been achieved. It has also been found that a longer tubular unit with the length to diameter (L/D) ratio of 10.5 is advantageous. The estimated pressure drop across the bed has been found to be negligible. Power consumption and productivity have also been computed.
Źródło:
Polish Journal of Chemical Technology; 2010, 12, 2; 18-28
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evidence of amorphous Ca-phosphate precipitate caused by bio mineralisation in 4-5th CE lime plasters of the previously submerged east coastal monument of Salvankuppam
Autorzy:
Singh, Manager R.
Kumar, S. Vinodh
Ganaraj, Kuntikana
Powiązania:
https://bibliotekanauki.pl/articles/2086560.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Mineralogiczne
Tematy:
Amorphous Ca-phosphate
16S rRNA
Bio-mineralization
calcite
lime plasters
Opis:
The lime plasters of the excavated monument of Salvankuppam, previously submerged and exposed by the Tsunami occurred in the Indian Ocean on 26th December 2004 was studied with different analytical techniques. The temple is dated 4-5th century CE. The XRF, XRD, FTIR, NMR, SEM-EDX analysis of the lime plasters evidenced particular occurrence of phosphatised bacterial remains in saline conditions. The formation of amorphous Ca-phosphate by bio mineralization was identified in the plasters by the analyses. The plasters are made of air-lime with coarse aggregates and seashells inclusion as confirmed by the thermal and chemical analysis. The microstructure and morphological investigations of mineralized microbial structures by SEM-EDX indicated the formation of amorphous Ca-phosphate. The unordered and fibrous spherulites have hardened and reduced porosity of the plaster by bio mineralization as observed through MIP analysis. The 16S rRNA sequencing has identified the Pseudomonas strains mainly responsible for the clustering of amorphous Ca-phosphate particles around the bacterial colony.
Źródło:
Mineralogia; 2021, 52, 1; 19--30
1899-8291
1899-8526
Pojawia się w:
Mineralogia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Covid-19 update: Omicron variant − a new emerging threat
Autorzy:
Mehta, S.
Gambhir, R.S.
Singh, B.
Goel, R.
Ghuman, K.S.
Aggarwal, A.
Powiązania:
https://bibliotekanauki.pl/articles/2083083.pdf
Data publikacji:
2022
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Tematy:
COVID-19
SARS-CoV-2 pandemic
Omicron variant
vaccine
coronavirus pandemic
Opis:
A new health threat in the form of a new variant of Covid-19 called Omicron has emerged globally in this holiday season. This new variant has been declared a variant of concern (VOC) by the World Health Organization and experts are expecting another wave of the pandemic. A lot still unknown about this variant and researchers worldwide are conducting studies to find the nature and characteristics of this mutated strain. Cases have begun to rise dramatically around the world and many countries have already imposed travel restrictions again to prevent disease transmission. It is being speculated that this particular variant has got tendency of immune escape and therefore can even infect fully vaccinated individuals. Vaccination and adhering to Covid-19 guidelines and protocols can curtail the spread of the virus. The present paper focuses on what is currently known about this variant, antigen diagnostic tests, importance of getting fully vaccinated and having booster dose etc. If we want to emerge from this pandemic, countries should practice vaccine equality and solidarity for the good of mankind.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2022, 73, 1; 13-16
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Towards use of dijkstra algorithm for optimal navigation of an unmanned surface vehicle in a real-time marine environment with results from artificial potential field
Autorzy:
Singh, Y.
Sharma, S.
Sutton, R.
Hatton, D.
Powiązania:
https://bibliotekanauki.pl/articles/116058.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
autonomous vehicles
dijkstra’s algorithm
Unmanned Surface Vehicle (USV)
port of portsmouth
Artificial Path Planning (APF)
Artificial Potential Field
real-time marine environment
optimal navigation
Opis:
The growing need of ocean surveying and exploration for scientific and industrial application has led to the requirement of routing strategies for ocean vehicles which are optimal in nature. Most of the op-timal path planning for marine vehicles had been conducted offline in a self-made environment. This paper takes into account a practical marine environment, i.e. Portsmouth Harbour, for finding an optimal path in terms of computational time between source and end points on a real time map for an USV. The current study makes use of a grid map generated from original and uses a Dijkstra algorithm to find the shortest path for a single USV. In order to benchmark the study, a path planning study using a well-known local path planning method artificial path planning (APF) has been conducted in a real time marine environment and effectiveness is measured in terms of path length and computational time.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2018, 12, 1; 125-131
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isolation and in vitro cytotoxic activity of 11-methylixoside isolated from bark of Randia dumetorum Lamk.
Izolacja i działanie cytotoksyczne in vitro 11-metyliksozydu wyizolowanego z kory Randia dumetorum Lamk.
Autorzy:
Jangwan, J.S.
Aquino, R.P.
Mencherini, T.
Singh, R.
Powiązania:
https://bibliotekanauki.pl/articles/71884.pdf
Data publikacji:
2013
Wydawca:
Instytut Włókien Naturalnych i Roślin Zielarskich
Tematy:
isolation
in vitro
cytotoxic activity
11-methylixoside
bark
Randia dumetorum
Rubiaceae
tree
medicinal plant
plant morphology
Opis:
Randia dumetorum (family Rubiaceae) is highly reputed ayurvedic medicinal tree commonly known as the Mainphal. A large deciduous thorny shrub grows up to 5 m of height. It occurs almost throughout India up to 1200 m of altitude. It is found in Himalaya from Jammu East ward ascending to 400 m and from Kashmir to East ward up to 1200 m. 11-methylixoside (compound 1), an iridoid glucoside, was isolated from the bark of this plant. The structure was characterized by using spectroscopic methods including 1D-1HNMR,13C-NMR and 2D-NMR (HSQC,HMBC, DQF-COSY) experiments and confirmed by comparison of their NMR data with those from the literature. This compound has been reported for the first time in Randia dumetorum bark. The 11-methylixoside was subjected to cytotoxic activity against MDA-MB-231 (breast cancer cell line) and SK-MEL-2 (human skin melanoma cell line), BE(2)C (neuroblastoma cell line derived from human bone marrow) and U87MG (human neuronale glioblastoma (astrozytom) cell line showed appreciable cytotoxic effect with IC50 value 63.10 µg/ml concentration for SK-MEL-2 (human skin melanoma cell line).
Randia dumetorum (rodzina Apiaceae) jest rośliną cenioną w medycynie aiurwedyjskiej, znaną pod nazwą Mainphal. Duży, liściasty, ciernisty krzew osiąga wysokość 5 m. Występuje praktycznie w całych Indiach do wysokości 1200 m. Można go znaleźć w Himalajach od Jammu (400 m) do Kaszmiru (1200 m). Z kory tej rośliny wyizolowano glukozyd irydoidowy 11-metyloksyd (składnik 1). Jego strukturę zbadano za pomocą metod spektroskopowych obejmujących 1D-1HNMR,13C-NMR i 2D-NMR (HSQC,HMBC, DQF-COSY) i potwierdzono poprzez porównanie jego NMR danych z danymi literaturowymi. Obecność tego składnika stwierdzono po raz pierwszy w korze Randia dumetorum. Działanie cytotoksyczne 11-metyliksozydu było badane przeciw MDA-MB-231 (linia komórkowa raka sutka) i SK-MEL-2 (linia komórkowa czerniaka), BE(2)C (linia komórkowa neuroblastomy uzyskana z ludzkiego szpiku kostnego) i U87MG (linia komórkowa ludzkiej glioblastomy (gwiaździak). Wykazano znaczne działanie cytotoksyczne z wartością IC50 w stężeniu 63.10 µg/ml przeciw SK-MEL-2 (linia komórkowa czerniaka).
Źródło:
Herba Polonica; 2013, 59, 1
0018-0599
Pojawia się w:
Herba Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Use of machine learning algorithm for the better prediction of SR peculiarities of WEDM of Nimonic-90 superalloy
Autorzy:
Singh Nain, S.
Sai, R.
Sihag, P.
Vambol, S.
Vambol, V.
Powiązania:
https://bibliotekanauki.pl/articles/378951.pdf
Data publikacji:
2019
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
support vector machine
Gaussian process
artificial neural network
WEDM
maszyna wektorów nośnych
proces gaussowski
sztuczna sieć neuronowa
Opis:
Purpose: With the end goal to fulfil stringent structural shape of the component in aeronautics industry, machining of Nimonic-90 super alloy turns out to be exceptionally troublesome and costly by customary procedures, for example, milling, grinding, turning, etc. For that reason, the manufacture and design engineer worked on contactless machining process like EDM and WEDM. Based on previous studies, it has been observed that rare research work has been published pertaining to the use of machine learning in manufacturing. Therefore the current research work proposed the use of SVM, GP and ANN methods to evaluate the WEDM of Nimonic-90. Design/methodology/approach: The experiments have been performed on the WEDM considering five process variables. The Taguchi L 18 mixed type array is used to formulate the experimental plan. The surface roughness is checked by using surface contact profilometre. The evolutionary algorithms like SVM, GP and ANN approaches have been used to evaluate the SR of WEDM of Nimonic-90 super alloy. Findings: The entire models present the significant results for the better prediction of SR peculiarities of WEDM of Nimonic-90 superalloy. The GP PUK kernel model is dominating the entire model. Research limitations/implications: The investigation was carried for the Nimonic-90 super alloy is selected as a work material. Practical implications: The results of this study provide an opportunity to conduct contactless processing superalloy Nimonic-90. At the same time, this contactless process is much cheaper, faster and more accurate. Originality/value: An experimental work has been reported on the WEDM of Udimet-L605 and use of advance machine learning algorithm and optimization approaches like SVM, and GRA is recommended. A study on WEDM of Inconel 625 has been explored and optimized the process using Taguchi coupled with grey relational approach. The applicability of some evolutionary algorithm like random forest, M5P, and SVM also tested to evaluate the WEDM of Udimet-L605.The fuzzy- inference and BP-ANN approached is used to evaluate the WEDM process. The multi-objective optimization using ratio analysis approach has been utilized to evaluate the WEDM of high carbon & chromium steel. But this current research work proposed the use of SVM, GP and ANN methods to evaluate the WEDM of Nimonic-90.
Źródło:
Archives of Materials Science and Engineering; 2019, 95, 1; 12-19
1897-2764
Pojawia się w:
Archives of Materials Science and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of inertia in the steady state pressurised flow of a non-Newtonian fluid between two curvilinear surfaces of revolution: Rabinowitsch fluid model
Autorzy:
Singh, U. P.
Gupta, R.S.
Kapur, V.K.
Powiązania:
https://bibliotekanauki.pl/articles/185617.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
efekt bezwładności
łożysko krzywoliniowe
zewnętrzny przepływ ciśnieniowy
curvilinear bearings
Rabinowitsch fluid model
inertia effect
externally pressurized flow
Opis:
In many practical situations fluids are normally blended with additives (viscosity index improvers, viscosity thickeners, viscosity thinners) due to which they show pseudoplastic and dilatant nature which can be modelled as cubic stress model (Rabinowitsch model). The cubic stress model for pseudoplastic fluids is adopted because Wada and Hayashi have shown that the theoretical results with this model are in good agreement with the experimental results. The present theoretical analysis is to investigate the pseudoplastic effect along with the effect of rotational inertia on the pressure distribution, frictional torque and fluid flow rate of externally pressurised flow in narrow clearance between two curvilinear surfaces of revolution. The expression for pressure has been derived using energy integral approach. To analyse and discuss the effects of pseudoplasticity and fluid inertia on the pressure distribution, fluid flow rate and frictional torque, the examples of externally pressurised flow in the clearance between parallel disks and concentric spherical surfaces have been considered.
Źródło:
Chemical and Process Engineering; 2011, 32, 4; 333-349
0208-6425
2300-1925
Pojawia się w:
Chemical and Process Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identifying monkeypox: do dental professionals have adequate knowledge and awareness?
Autorzy:
Kaur, A.
Goel, R.
Singh, R.
Bhardwaj, A.
Kumari, R.
Gambhir, R.S.
Powiązania:
https://bibliotekanauki.pl/articles/28765560.pdf
Data publikacji:
2022
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Opis:
Background. The emergence of monkeypox has presented a new challenge for health agencies around the globe. There is significant increase in the number of cases that too in non-endemic countries with more than 18000 cases reported worldwide. Objective. The present study was conducted to assess knowledge and awareness regarding monkeypox among dental professionals. Materials and Method. The present cross-sectional study among 410 subjects who were residing in a northern state of the country. Informed consent was obtained from all the subjects. Study sample was selected on the basis of Systematic random sampling methodology. A self-designed close-ended questionnaire written in English and verified by experts was utilized for the study. The questionnaire was delivered personally to study subjects to collect the required information. Chi-square test and ANOVA were used for statistical analysis. Results. One-fourth (24.8%) of the subjects never heard about monkeypox disease. Negative response was given by 44.8% of subjects regarding resemblance of monkeypox with small pox. Only 31.2% of subjects had knowledge regarding oral manifestations of the disease. High knowledge scores were reported by only 28% of subjects. Higher knowledge levels were significantly related to education level and working profile of study subjects. Online media (Internet) was preferred as the main source to obtain more information by 42.2 of subjects. Conclusion. There was low level of knowledge regarding monkeypox among study subjects. There is an urgent need for dental professionals to keep themselves updated with recent knowledge on new emerging infectious diseases.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2022, 73, 3; 365-371
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Omicron sub-variants: is the world going to witness another wave?
Autorzy:
Aggarwal, A.
Nirola, A.
Singh, R.
Goel, R.
Gupta, A.
Gambhir, R.S.
Powiązania:
https://bibliotekanauki.pl/articles/28765575.pdf
Data publikacji:
2022
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Opis:
Omicron, the new ‘Variant of Concern’ of SARS-CoV-2, is rapidly evolving into new sub-variants or sub-lineages (BA.1, BA.2 etc.). These sub-variants have higher transmissibility, decreased vaccine effectiveness and increased risk of reinfection. As a result, many nations across the globe are reporting surge in infections which is a matter of concern. Understanding Omicron and its sub-variants is vital for development of public health policy and preventing disease transmission. The present paper throws a spotlight on the newly detected sub-variants of Omicron as reported in ongoing researches which are available only in pre-print form and also the importance of a booster dose of the vaccine. Information regarding recent research on a new nasal vaccine formulation, which may be effective against the new variants, is also highlighted in the paper.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2022, 73, 2; 159-162
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of dental professionals’ maintenance of management practices developed and incorporated during COVID-19 pandemic – a cross-sectional study
Autorzy:
Singh, R.
Sekhon, T.
Sekhon, S.
Kumar, M.
Nirola, A.
Gambhir, R.S.
Powiązania:
https://bibliotekanauki.pl/articles/28765158.pdf
Data publikacji:
2023
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Opis:
Background. COVID-19 pandemic has been a source of emerging public health problems for the past few years. Due to its contagious nature, health care professionals especially dentists, incorporated various modifications in their practices to prevent themselves and their patients from the risk of getting infected. Objective. The present study aims to assess whether dental professionals are still continuing with those modifications in practice in current times. Materials and Methods. The present study was conducted on 415 subjects after getting due approval from concerned authorities and consent from the subjects. Systematic random sampling methodology was employed for selection for study sample. The study employed a self-constructed questionnaire which was divided into 2 parts and information regarding demographic profile, practice modifications and safety protocols was gathered from subjects. Statistical analysis was conducted using Chi-square test and multiple regression analysis. Results. Only 8.6% of subjects were currently continuing with their all previous practice modifications. A vast majority of subjects (83.8%) were not deferring treatment of patients showing suspicious symptoms. Approximately 89% of subjects were not sanitizing the operating area at the end of the working day. More than two-thirds (76.4%) of the subjects stated that the pandemic was over. Female gender (OR:1.67) and high level of education (OR:2.45) had an important effect on the continuation of practice modifications. Conclusion. Very few subjects were adhering to all practice modifications previously incorporated. Dental professionals should not let their guard down even if COVID-19 cases have reduced considerably. The information collected will be useful for the dental community and further studies should be carried out.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2023, 74, 3; 309-314
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temperature and Rainfall Trend in Alaknanda Valley Srinagar Garhwal, Uttarakhand, India
Autorzy:
Negi, R. S.
Sagar Gautam, Alok Sagar
Singh, Santosh
Powiązania:
https://bibliotekanauki.pl/articles/1164126.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Climate Change
Meteorological data
Rainfall
Temperature
Trend
Opis:
The rainfall and temperatures are the most important parameters among the atmosphere as these parameters decide the ecological situation of the specific area, which affects the agricultural productivity. The temperature, and rainfall trends are analysed for meteorological data of Automatic Weather Station (AWS), was installed September 2009 with 22 meteorological parameters in the Department of Rural Technology, HNB Garhwal, University, Srinagar Garhwal, and Uttarakhand. In the study assess the seven-year change in temperature and rainfall has been examination by linear tread analysis. It is observed that in velley of Srinagar Garhwal, Uttarakhand, coefficient of variation for mean temperature for Srinagar Garhwal Valley is highest in the month of February and lowest in the month of August. This means that mean temperature is most stable in the month of August and total monthly rainfall observed highest in the month of November and minimum for the month of July. This shows that rainfall is more stable in the month of July and is more variable in the month of November for the Valley.
Źródło:
World Scientific News; 2018, 108; 207-214
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemical constituents of ethanol extract of leaves and molluscicidal activity of crude extracts from Vitex trifolia Linn.
Składniki chemiczne etanolowego wyciągu z liści i działanie przeciwślimakowe nieoczyszczonego wyciągu z Vitex trifolia Linn.
Autorzy:
Jangwan, J.S.
Aquino, R.P.
Mencherini, T.
Picerno, P.
Singh, R.
Powiązania:
https://bibliotekanauki.pl/articles/71567.pdf
Data publikacji:
2013
Wydawca:
Instytut Włókien Naturalnych i Roślin Zielarskich
Tematy:
chemical constituent
ethanol extract
leaf
molluscicidal activity
crude extract
Vitex trifolia
Verbenaceae
beta-sitosterol
ursolic acid acetate
Opis:
β-sitosterol and two triterpenoids: ursolic acid acetate and platanic acid have been isolated from ethanolic extract of Vitex trifola leaves. β-sitosterol was previously isolated from the leaves, stem and seeds of Vitex trifolia. Ursolic acid acetate has been isolated for the first time in this plant species. Platanic acid has been reported for the first time in Vitex trifolia and even in the family of this plant: Verbenaceae. These compounds were characterized using spectroscopic methods including 1D-1HNMR, 13CNMR, ESIMS and 2D-NMR (HSQC, HMBC, COSY) experiments and confirmed by comparison of their NMR data with those from the literature. A preliminary molluscicidal test for ethanol, chloroform and n-hexane extracts of leaves of Vitex trifolia against Biomphalaria alexandrina adult snails showed that ethanol extract of leaves with LC50 value 26.42 mg/l (27.92 mg/l – 24.99 mg/l) was more effective than n-hexane extract with LC50 value 35.48 mg/l (43.81 mg/l – 28.72mg/l) and chloroform extract with LC50 value 46.77 mg/l (53.59 mg/l – 43.81 mg/l) after 24 h exposure.
Z etanolowego wyciągu z liści Vitex trifola wyizolowano β-sitosterol i dwa triterpenoidy: octan kwasu ursolowego i kwas platanowy. Poprzednio z liści, łodyg i nasion Vitex trifola był wyizolowant β-sitosterol. Octan kwasu ursolowego został wyizolowany po raz pierwszy z rośliny tego gatunku. Występowanie kwasu platanowego w Vitex trifolia oraz w rodzinie Verbenaceae zostało opisane po raz pierwszy. Składniki te scharakteryzowano, używając metod spektroskopowych, stosując badania 1D-1HNMR, 13CNMR, ESIMS and 2D-NMR (HSQC, HMBC, COSY) oraz potwierdzono porównaniem ich danych NMR z danymi literaturowymi. Wstępny test działania przeciwślimakowego wyciągów etanolowego, chloroformowego i n-heksanowego z liści Vitex trifolia przeciw dorosłym ślimakom Biomphalaria
Źródło:
Herba Polonica; 2013, 59, 4
0018-0599
Pojawia się w:
Herba Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of organic inputs on strength and stability of soil aggregates under rice-wheat rotation
Autorzy:
Das, B.
Chakraborty, D.
Singh, V.K.
Aggarwal, P.
Singh, R.
Dwivedi, B.S.
Powiązania:
https://bibliotekanauki.pl/articles/25472.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
tensile strength
stability
soil aggregate
rice
wheat
cereal crop rotation
Opis:
The study aims to elucidate the impact of organic inputs on strength and structural stability of aggregates in a sandy loam soil. Tensile strength, friability and water stability of aggregates, and the carbon contents in bulk soil and in large macro (>2 mm), small macro (0.25-2 mm), micro (0.053-0.25 mm) and silt+clay size (<0.053) aggregates were evaluated in soils from a long-term experiment with rice-wheat rotation at Modipuram, India, with different sources and amounts of organic C inputs as partial substitution of N fertilizer. Addition of organic substrates significantly improved soil organic C contents, but the type and source of inputs had different impacts. Tensile strength of aggregates decreased and friability increased through organic inputs, with a maximum effect under green gram residue (rice)-farmyard manure (wheat) substitution. Higher macroaggregates in the crop residue- and farmyard manure-treated soils resulted in a higher aggregate mean weight diameter, which also had higher soil organic C contents. The bulk soil organic C had a strong relation with the mean weight diameter of aggregates, but the soil organic C content in all aggregate fractions was not necessarily effective for aggregate stability. The soil organic C content in large macroaggregates (2-8 mm) had a significant positive effect on aggregate stability, although a reverse effect was observed for aggregates <0.25 mm. Partial substitution of nitrogen by organic substrates improved aggregate properties and the soil organic C content in bulk soil and aggregate fractions, although the relative effect varied with the source and amount of the organic inputs.
Źródło:
International Agrophysics; 2014, 28, 2
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Tungsten on Aluminized Melt Cast High Explosive Formulations
Autorzy:
Mishra, V. S.
Bhagat. A., L.
Vadali, S. R.
Singh, V. K.
Wasnik, R. D.
Asthana, S.
Powiązania:
https://bibliotekanauki.pl/articles/358355.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
tungsten
MOUT
low intensity conflict
peak over pressure
impulse
Opis:
Aluminized 2,4,6-trinitrotoluene (TNT) based, melt-cast, high explosive compositions are widely used in warheads. These compositions offer a blast effect over a larger period due to the secondary combustion of aluminum. During recent times tungsten based explosives have been reported for lethality at close range to avoid collateral damage in low intensity conflicts (LIC) and find application in shaped charges to enhance their penetration capability. This paper reports findings on tungsten-based, melt-cast, explosive formulations. The compositions were prepared by substituting aluminum with tungsten in the reference aluminized, high explosive formulation. The compositions were characterized for their sensitivity to mechanical/shock stimuli, velocity of detonation (VOD) and blast performance. The study reveals that the impact sensitivity remains comparable on incorporating 10% tungsten at the cost of aluminum whereas an increase in tungsten content to 20% leads to an increase in impact sensitivity. However friction sensitivity and shock sensitivity remained more or less unchanged. The velocity of detonation (VOD) of tungsten-loaded, aluminized formulations is found to be comparable to the standard aluminized formulation. The peak over pressure of tungsten-based formulations is lower than the reference, aluminized composition at close range but is almost unchanged at long range. The impulse of tungsten-based formulations is also lower than the reference, aluminized composition. The reduction in impulse at close range is substantial on replacing 10% aluminum with inert tungsten.
Źródło:
Central European Journal of Energetic Materials; 2012, 9, 2; 147-154
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lura - indiogenous approach to biodiversity conservation by temporary community confinement of Mithuns (Bos frontalis) during growing season
Autorzy:
Jini, D.
Bhagawati, K.
Singh, R.
Bhagawati, R.
Alone, R.A.
Ngachan, S.V.
Powiązania:
https://bibliotekanauki.pl/articles/11397.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Opis:
The extraordinary knowledge of indigenous people about their immediate environment and natural resource base can be a great asset for conservation of biodiversity. The current study aims to investigate an indigenous method of grazing management through temporary confinement of Mithun (Bos frontalis) of whole village community in a well selected area in the forest during the cropping and growing season. The whole system is called Lura and practiced by Galo tribes of Eastern Himalayan region of India. Every year Lura management committee is formed that selects a new site based on number of Mithuns, forage availability, time period and several other key criteria without affecting flora-fauna diversity and rare medicinal plants. The practice checks continuous, free, random and selective grazing by Mithuns. It prevent continuous disturbance of soil surface due to treading, during growing and rainy seasons that avoid soil erosion and compaction, and facilitate seedling germination and the invasion by plants. Change of site, provide resting period to the forages in the previous Lura site especially during growth stage that allow them to renew and regenerate appreciably within 1-2 months. It also saves resources and time for construction of fencing in each Jhum and other agricultural site of each farmer. The confinement offers easy monitoring, protection and regular health assessment of the livestock. Thus, it is a multifaceted indigenous practice that ensures grazing management, biodiversity conservation, protection of standing agricultural crops and animal health management
Źródło:
International Letters of Natural Sciences; 2015, 44
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of van Hove Singularity on T$\text{}_{c}$ in Rb doped C$\text{}_{60}$
Autorzy:
Agrawal, B. K.
Agrawal, S.
Yadav, P. S.
Srivastava, P.
Srivastava, R.
Singh, S.
Powiązania:
https://bibliotekanauki.pl/articles/2035748.pdf
Data publikacji:
2003-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Jb
74.62.Fj
74.70.Wz
Opis:
In the present study we investigate the role of van Hove singularity on the optimization of T$\text{}_{c}$ in Rb doped fullerenes C$\text{}_{60}$ Rb$\text{}_{3}$. A first principles self-consistent full potential linear muffin-tin orbital method using density functional theory in local density approximation was employed. The doped Rb atoms are of two types occupying the tetrahedral and interstitial positions in the fcc lattice. The added Rb atoms fill the t$\text{}_{1u}$ band of the undoped fullerenes C$\text{}_{60}$ up to half which makes C$\text{}_{60}$Rb$\text{}_{3}$ conducting. Saddle points leading to van Hove singularities are observed in the neighbourhood of the symmetry point L. The shifting of the van Hove singularity with the volume of the lattice is investigated. We observe a saddle point just at the Fermi level for a lattice constant of 14.435Å. The highest value of T$\text{}_{c}$ should thus be observed at the above lattice constant. This result is in excellent agreement with the observed high value of T$\text{}_{c}$ measured in C$\text{}_{60}$Rb$\text{}_{3}$ for a lattice constant of 14.435Å.
Źródło:
Acta Physica Polonica A; 2003, 103, 5; 477-482
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Ammonium Sulfamate Nitration for the Preparation of Ammonium Dinitramide
Autorzy:
Mandal, A. K.
Kunjir, G. M.
Singh, J.
Adhav, S. S.
Singh, S. K.
Pandey, R. K.
Bhattacharya, B.
Lakshmi Kantam, M.
Powiązania:
https://bibliotekanauki.pl/articles/358022.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Opis:
The reaction kinetics for the preparation of ammonium dinitramide (ADN) is described. ADN is the ammonium salt of the dinitramide anion, and belongs to the group of inorganic oxidizers, mainly useful for energetic rocket propellant formulations, particularly for underwater applications. It is also a potential candidate to replace ammonium perchlorate (AP), in order to develop chlorine-free, green propellants. At HEMRL, ADN is prepared by the nitration of ammonium sulfamate (AS) using mixed acid, followed by hydrolysis, neutralization with ammonia (g) and rectification using solvent. The nitration of ammonium sulfamate (AS) is carried out at a subzero temperature of -40 ±1 °C. The yield of ADN is reliant on the formation of dinitramidic acid, an intermediate product formed during the hydrolysis step, and its stability is predominantly dependent upon the level of acidity and temperature of the reaction medium. Prior to these kinetics studies, process optimization of the nitration of ammonium sulfamate (AS) was performed and gave the final mole ratio of AS:HNO3:H2SO4. Since the nitration of AS is sensitive to temperature, the rate of reaction was studied at fixed temperatures with variation of time, keeping all of the other parameters, such as vessel volume, agitator speed, feed rate etc., constant. During these studies, predetermined quantities of ammonium sulfamate (AS) and mixed acid were allowed to react at a fixed temperature (-40 ±1 °C) for different reaction periods to generate the concentration profile of AS. Using this concentration profile, the reaction order and reaction rate constant were evaluated. In order to find the effect of temperature on the reaction rate and yield, experiments were conducted at other temperatures such as -30 and -50 °C. In the present studies, it was found that the optimum temperature of nitration is -40 ±1 °C and that the rate of reaction follows a pseudo second order process with rate constant 0.01113 (min-1)•(mol/L)-1. The reaction time evaluated for 55 to 60% conversion is about 70-80 minutes at -40 ±1 °C, based on this kinetics. The activation energy of AS nitration was found to be -4.6 kcal/mol, using the reaction kinetic data based on the temperature dependent rate equation derived from Arrhenius’s law.
Źródło:
Central European Journal of Energetic Materials; 2014, 11, 1; 83-97
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assay of the Insensitive High Explosive 3-Nitro-1,2,4-triazol-5-one (NTO) by Acid-Base Titration
Autorzy:
Nandi, A. K.
Singh, S. K.
Kunjir, G. M.
Singh, J.
Mandal, A. K.
Pandey, R. K.
Powiązania:
https://bibliotekanauki.pl/articles/358351.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
NTO
purity
acid-base titration
HPLC
quality control
Opis:
The insensitive high explosive 3-nitro-1,2,4-triazol-5-one (NTO) is a weak acid (pKa 3.76) due to the labile N–H bond. The weakly acidic character of this compound is exploited for its assay by aqueous acid-base titration. The NTO sample was dissolved in water and the resultant solution was titrated against 0.07 N NaOH solution using phenolphthalein as indicator. Regular batch samples were assayed by this method and the results were compared with those obtained by the HPLC method. The aqueous acid-base titration method was found to be suitable for the quality control of the product.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 1; 113-122
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability analysis of a shallow depth metro tunnel: a numerical approach
Analiza stabilności płytkiego tunelu metra z wykorzystaniem metod numerycznych
Autorzy:
Monjezi, M.
Rahmani, B. N.
Torabi, S. R.
Singh, T. N.
Powiązania:
https://bibliotekanauki.pl/articles/219211.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
modelowanie numeryczne
gwoździowanie gruntu
drążenie tuneli przy pomocy tarcz
szkody górnicze
osiadanie gruntu
numerical modelling
soil nailing
shield tunnelling
subsidence
Opis:
In this paper, an attempt has been made to use numerical modelling for simulating a long halt in construction process at a shallow depth metro tunnel and investigate the effects of soil nailing to increase the tunnel face strength. Finite difference software FLAC with high applicability in a continuum environment was adopted for this study. The tunnel is being excavated for Tehran metro project. Shield tunnelling with roadheader and back hoe cutting tools is applied in the excavation process. Mohr-Coulomb elasto-plastic constitutive law is considered to model the ground. After two months halting in excavation process, tunnel instability and ground subsidence were recorded in thirteen different monitoring points. Numerical simulation results showed a close approximation (11-16%) between measured and FLAC computed displacements of the tunnel crown in case of unsupported face, which is in close proximity and a proof indicates the reliability of simulation. Also, simulation results exhibit a significant reduction in the ground subsidence and tunnel instability in case of supported face by means of the soil nailing.
W artykule podjęto próbę wykorzystanie metod modelowania numerycznego dla potrzeb symulacji dłuższego przestoju prac związanych z budową płytkiego tunelu metra w celu zbadania skutków wzmacniania gruntu dla zwiększenia wytrzymałości tunelu w części czołowej. W badaniach zastosowano oprogramowanie wykorzystujące metodę różnic skończonych FLAC, do zastosowań w środowisku ciągłym. Wykop tunelu wykonywany jest w ramach budowy metra w Teheranie. Kopanie tunelu odbywa się przy pomocy urządzeń tarczowych do drążenia tuneli oraz urządzeń podsiębiernych do urabiania. Do modelowania gruntu zastosowano model sprężysto-plastyczny Mohra-Coulomba z wykorzystaniem równania konstytutywnego. Po dwumiesięcznym przestoju w pracach budowlanych, zarejestrowano wielkości niestabilności tunelu oraz osiadania gruntu w trzynastu równych punktach pomiarowych. Wyniki symulacji numerycznych wykazały wysoką zbieżność (11-16%) pomiędzy wartościami zmierzonymi a przemieszczeniami obliczonymi przy wykorzystaniu oprogramowania FLAC dla stropu tunelu w niepodpartej części czołowej, co potwierdza wiarygodność wyników symulacji. Ponadto, wyniki symulacji wykazują znaczne zmniejszenie osiadania gruntu i niestabilności tunelu w części czołowej tunelu wzmocnionej przez podbijanie gruntu.
Źródło:
Archives of Mining Sciences; 2012, 57, 3; 535-545
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tribological behavior, mechanical properties and microstructure of Al-12Si-ZrC composite prepared by powder metallurgy
Autorzy:
John, C. F.
Paul, R. C.
Singh, S. C. E.
Ramkumar, T.
Powiązania:
https://bibliotekanauki.pl/articles/201910.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
wear
friction
aluminium
silicon
zirconium carbides
powder metallurgy
tarcie
krzem
węgliki cyrkonu
metalurgia proszków
Opis:
High-energy mechanical alloying method was used to prepare Al-12Si-xZrC (x = 0, 5, 10, 15 wt. %) nanocomposites. Cylindrical preforms were prepared with an initial preform density of 89% by using a suitable die and punch assembly. The preforms were sintered in a muffle furnace with an inert gas atmosphere at a temperature of 550°C, followed by cooling until room temperature has been attained. Scanning electron microscope (SEM) and X-ray diffraction (XRD) techniques were used to characterize the composites. Pin-on-disc wear testing machine was used to determine the tribological properties of the prepared composites. The results show that the wear loss reduced with increasing the reinforcement content and coefficient of friction increases gradually.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2017, 65, 2; 149-154
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identifying overlapping phylogenetic and geographic roots of HIV - 1 evolution through computational analyses
Autorzy:
Singh, P.K.
Banik, R.
Chakraborty, H.J.
Das, S.G.
Ganguli, S.
Datta, A.
Powiązania:
https://bibliotekanauki.pl/articles/11359.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
phylogenetic root
geographic root
evolution
computational analysis
HIV-1
genome
recombinant strain
AIDS
human disease
acquired immunodeficiency syndrome zob.AIDS
acquired immune deficiency syndrome zob.AIDS
Opis:
HIV-1 or Human Immuno Deficiency Virus-1 is the main causative agent of Acquired Immuno Deficiency Syndrome (AIDS). Human host infected with HIV - 1 extensively harbours many viral variants but very little is known about the difference in pattern[17] of evolution of phylogenetic lineages of HIV-1 non recombinant, normal inter subtype recombinant and main two specific recombinant forms of HIV-1 i.e., Circulating Recombinant Forms (CRFs) and Unique Recombinant Forms (URFs). This study is mainly concerned with study of the difference in evolutionary lineages of non-recombinant and recombinant sequences of HIV-1 genome sequences and identification of geographically rich areas which has reported high degree of HIV-1 occurrence and variety. Total 1550 HIV-1 genome sequences were obtained from HIV Los Alamos Database. The sequences were aligned using MAFFT (Multiple Alignment using Fast Fourier Transform) web server tool. Alignment was carried out using 10 different set of alignment parameter values. After alignment the aligned file was used for constructing N-J phylogenetic tree using Clustal X2 tool. Phylogenetic analysis was performed keeping in mind the category to which the sequence belongs. Upon analysis it was observed that the clade containing the probable ancestor belongs remained constant in all cases of different alignment values. Non recombinant isolates, inter subtype recombinants, CRFs, URFs all followed different patterns of evolution. Non recombinant sequences were found geographically specific and subtype specific to some extent whereas, normal recombinants were subtype specific and less geographically specific. CRFs showed variation among the pattern of their evolution. At some instances the sequences occurred as sister taxa of non-recombinant or normal inter subtype recombinant sequences, while at some instances as sister taxa of other CRFs where they were geographically specific. Three CRFs existed as completely diverged sequences. URFs were four in number; two of them were Indian isolates of while other two were Japanese isolates. URFs were found to be totally geographically specific. Geography wise high rate of variation was observed in India and Japan as these two countries had sequences belonging to all of the above categories. Cameroon and South Africa have very large number isolates and a considerable amount of genetic variation among isolates but they lack URFs.
Źródło:
International Letters of Natural Sciences; 2014, 02
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An ailuravine rodent from the lower Eocene Cambay Formation at Vastan, western India, and its palaeobiogeographic implications
Autorzy:
Rana, R S
Kumar, K.
Escarguel, G.
Sahni, A.
Rose, K.D.
Smith, T.
Singh, H.
Singh, L.
Powiązania:
https://bibliotekanauki.pl/articles/23190.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Ischyromyidae
Cambay Formation
paleontology
Euromys inexpectatus
Euromys cardosoi
Rodentia
Eocene
India
Ailuravinae
Meldimys musak
Mammalia
ailuravine rodent
new species
Ailuravus michauxi
rodent
paleobiogeography
Western India
Opis:
A new ailuravine rodent, Meldimys musak sp. nov. (Mammalia: Rodentia, Ischyromyidae), is recorded from the lower Eocene lignites of western India. It is the oldest record of Rodentia from India. M. musak is more derived than the earliest Eocene ailuravine Euromys cardosoi from Portugal and more generalized than late early Eocene E. inexpectatus and Ailuravus michauxi from France. Its dental morphology closely corresponds to the middle early Eocene species M. louisi, which lived about 52 Ma in Western Europe. Meldimys was previously known only from Europe, and ailuravines were previously reported only from Europe and North America. Its occurrence in India allows the first direct correlation between the early Eocene land mammal horizons of Europe and India, and raises the possibility of a terrestrial faunal exchange between India and Eurasia close to the Palaeocene–Eocene transition.
Źródło:
Acta Palaeontologica Polonica; 2008, 53, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effective and Large Scale In vitro Propagation of Dendrocalamus strictus (Roxb.) Nees using Nodal Segments as Explants
Autorzy:
Rajput, Bharat Singh
Jani, Minal D.
Gujjar, M. R.
Shekhawat, M. S.
Powiązania:
https://bibliotekanauki.pl/articles/1066294.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Dendrocalamus strictus
axillary shoots
hardening
in vitro propagation
rooting
Opis:
Dendrocalamus strictus (Roxb.) Nees belongs to the family Poaceae is the most important and fastest growing bamboo species. An effort has been made to propagate D. strictus using nodal explants selected from mature mother plants. The disinfected nodes were inoculated on agar gelled Murashige and Skoog’s (MS) basal medium with various concentrations of 6-benzylaminopurine (BAP), while maximum 4-5 shoots were induced on 4.0 mg/l BAP. The newly formed buds were transferred to solidified MS basal medium containing 3.0 mg/l BAP and 0.5 α-Naphthalene acetic acid (NAA) to achieve about 26 multiple shoots. These experiments were conducted with a cluster of minimum 3-5 shoots. The induction of roots from in vitro regenerated shoots was found difficult in this plant system. Three types of auxins i.e. indole-3 butyric acid (IBA), indole-3 acetic acid (IAA) and NAA were used in various combinations for rooting of shoots. About 93 % rooting was archived on half strength MS medium augmented with 3.0 mg/l NAA. The rooted shoots were hardened in the greenhouse for two months and the secondary hardened plantlets were successfully shifted to the farmer’s field. More than 90 % survival rate was observed under the natural conditions in this plant species.
Źródło:
World Scientific News; 2019, 130; 238-249
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Leaching of Al-Based Polygrain Quasicrystalline and Related Crystalline Surfaces
Autorzy:
Yadav, T.
Mishra, S.
Pandey, S.
Singh, D.
Lowe, M.
Tamura, R.
Mukhopadhyay, N.
Srivastava, O.
McGrath, R.
Sharma, H.
Powiązania:
https://bibliotekanauki.pl/articles/1373698.pdf
Data publikacji:
2014-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.44.Br
81.16.Hc
61.66.Dk
68.37.Hk
Opis:
In the present investigation, we have studied leaching on polygrain Al-based quasicrystalline $(i-Al_{63}Cu_{25}Fe_{12})$ as well as crystalline (B2 phase; $Al_{55}Cu_{30}Fe_{15})$ alloy surfaces using a 10 mole NaOH solution. The surface was leached at varying times from 30 min to 8 h and subsequently characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray analysis. Leaching of the samples for 30 min generated a homogeneous layer. However further leaching for 1-8 h yielded nano-size particles on the surface. Spherical microstructure has been observed on the Al-Cu-Fe crystalline surface whereas on the quasicrystalline surface a petal-like microstructure appeared. The implications of the evolution of different microstructures in the context of structure, stability and activity are discussed. The results are compared with the microstructure of leached polygrained samples containing a mixture of different surface orientations.
Źródło:
Acta Physica Polonica A; 2014, 126, 2; 629-632
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Studies on Advanced Sheet Explosive Formulations Based on 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and Hydroxyl Terminated Polybutadiene (HTPB), and Comparison with a RDX-based System
Autorzy:
Jangid, S. K.
Talawar, M. B.
Singh, M. K.
Nath, T.
Sinha, R. K.
Powiązania:
https://bibliotekanauki.pl/articles/358055.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
hazardous materials
sheet explosive
explosive reactive armour (ERA)
CL-20
RDX
Opis:
The present investigation reports the use of 2,4,6,8,10,12-hexanitro2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) in sheet explosive formulations. In this study, hydroxyl terminated polybutadiene (HTPB) based sheet explosives were prepared incorporating the powerful explosive CL-20 as a partial replacement for hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX). The effects of incorporating CL-20 on the performance, sensitivity, thermal and mechanical properties of the sheet explosive compositions are reported. Sheet explosive formulation containing 80% of RDX and 20% of HTPB-binder was studied as control sample. HTPBbinder consisted of 12% HTPB, 2.9% dioctyl adipate (DOA) and 5.1% dioctyl phthalate (DOP). HTPB was cured with 4,4’-methylene diphenyl di-isocyanate (MDI) to form urethane linkages. The incorporation of 20% of CL-20 in place of RDX led to a remarkable increase in the velocity of detonation (VOD), of the order of 7680 m/s, and to better mechanical properties in terms of tensile strength (1.14 MPa) compared to the control formulation [RDX /HTPB-binder (80/20)]. The 20% CL-20 incorporated sheet explosive formulation also showed remarkable increases in impact and shock sensitivity. Thermal analysis of the sheet explosive compositions has also been carried out using differential scanning calorimetry (DSC).
Źródło:
Central European Journal of Energetic Materials; 2016, 13, 1; 135-147
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assay of the Insensitive High Explosive FOX-7 by Non-Aqueous Titration
Autorzy:
Nandi, A. K.
Paramasivan, P.
Singh, S. K.
Mandal, A. K.
Pandey, R. K.
Powiązania:
https://bibliotekanauki.pl/articles/358156.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
1,1-diamino-2,2-dinitroethene
FOX-7
non-aqueous titration
N,N-dimethylformamide
Opis:
A non-aqueous titration method was developed to assay the insensitive high explosive 1,1-diamino-2, 2-dinitroethene (FOX-7). The weak acidic nature of FOX-7 (pKa 10.6) was exploited in the assay method. The sample was dissolved in the protophilic solvent N, N-dimethylformamide and titrated against sodium methoxide solution in benzene/methanol using azo violet as indicator. FOX-7 samples obtained from regular batch operations were assayed by this method and the results were compared with that of a recrystallized sample. The method is simple, rapid and has good accuracy and precision.
Źródło:
Central European Journal of Energetic Materials; 2012, 9, 4; 343-352
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies on High Burning Rate Composite Propellant Formulations using TATB as Pressure Index Suppressant
Autorzy:
Mehilal, -
Jawalkar, S.
Kurva, R.
Sundaramoorthy, N.
Dombe, G.
Singh, P. P.
Bhattacharya, B.
Powiązania:
https://bibliotekanauki.pl/articles/951502.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
composite propellant
ammonium perchlorate
TATB
pressure index suppressant
Opis:
High burning rate propellant compositions are generally used in gas generators to eject missile from canister. Because of high burning rate, pressure index of the composition increases during burning. To reduce the pressure index, a high burning rate composite propellant formulations (~20 mm/s) based on AP/HTPB/Al have been prepared by incorporating TATB and studied in detail for viscosity build-up, thermal and mechanical properties, sensitivity as well as burning rate and pressure index (n). The data indicate that there is a decrease in end of mix viscosity on increasing the percentage of TATB. The same trend was also observed with mechanical properties while significant improvement in overall thermal stability was clearly observed. The sensitivity data indicate that impact and friction values show decreasing trend infer better safe to handle. The burn rate data reveal that on addition of TATB from 0.5 to 2% decrease in burning rate was not observed while on addition of further TATB up to 5% and beyond this significant decrease in burning rate was observed. The data on pressure index (n) also reveal that TATB is very effective in reducing the 'n' value up to 2% and beyond this 'n' value increases close to standard composition. The data on 'n' value reveal that it reduces from 0.47 to that of standard composition to 0.36 for the compositions containing TATB up to 2.0% in the pressure range of 60-90 kg/cm2.
Źródło:
Central European Journal of Energetic Materials; 2012, 9, 3; 237-249
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First tillodont from India: Additional evidence for an early Eocene faunal connection between Europe and India?
Autorzy:
Rose, K D
Rana, R.S.
Sahni, A.
Kumar, K.
Singh, L.
Smith, T.
Powiązania:
https://bibliotekanauki.pl/articles/22886.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
tillodont
India
Europe
Eocene
Paleocene
faunal connection
Cenozoic
mammal
Ypresian
anthracobunid
lagomorph
fauna
Opis:
Vastan Lignite Mine in southeastern Gujarat, India, produces the oldest known Cenozoic land−mammals and the only early Eocene continental vertebrate fauna known from India (e.g., Bajpai et al. 2005; Rana et al. 2005, 2008; Rose et al. 2006, 2008, 2009; Smith et al. 2007; Rage et al. 2008). The fauna comes from the Cambay Shale Formation and has been dated as middle Ypresian (~52 Ma, early Cuisian) based on a common nummulitid foraminiferan from about 15 m above the vertebrate−producing layer (Sahni et al. 2006; Rana et al. 2008). However, a recent study of dinoflagellate cysts from the section suggests that the deposits may be as old as 54–55 Ma (Garg et al. 2008). Although some elements of the fauna, such as anthracobunids and lagomorphs, have Asian affinities, a surprising number of taxa among the snakes, bats, insectivores, primates, rodents, and artiodactyls appear to be most closely related to early Eocene European or North American taxa. This may simply reflect the poor state of knowledge of contemporary south Asian vertebrate faunas; alternatively, it might be evidence of previously unsuspected early Eocene faunal exchange between Europe and southwest Asia. We report here two teeth of a tillodont from Vastan Mine, which constitute the first record of the mammalian order Tillodontia known from India. Despite the much greater generic diversity of tillodonts in Asia than elsewhere, the Vastan tillodont shows clear affinities with Euramerican esthonychines.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 2; 351-355
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł

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