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Wyszukujesz frazę "Verma, A." wg kryterium: Wszystkie pola


Tytuł:
Effect of hall currents on thermal instability of dusty couple stress fluid
Autorzy:
Aggarwal, A. K.
Verma, A.
Powiązania:
https://bibliotekanauki.pl/articles/240229.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
couple-stress fluid
dust particles
hall currents
stationary convection
oscillatory modes
magnetic field
ziarna pyłu
konwekcja
pole magnetyczne
Opis:
In this paper, effect of Hall currents on the thermal instability of couple-stress fluid permeated with dust particles has been considered. Following the linearized stability theory and normal mode analysis, the dispersion relation is obtained. For the case of stationary convection, dust particles and Hall currents are found to have destabilizing effect while couple stresses have stabilizing effect on the system. Magnetic field induced by Hall currents has stabilizing/destabilizing effect under certain conditions. It is found that due to the presence of Hall currents (hence magnetic field), oscillatory modes are produced which were non-existent in their absence.
Źródło:
Archives of Thermodynamics; 2016, 37, 3; 3-18
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photocatalytic, Sonolytic and Sonophotocatalytic Degradation of 4-Chloro-2-Nitro Phenol
Autorzy:
Verma, A.
Kaur, H.
Dixit, D.
Powiązania:
https://bibliotekanauki.pl/articles/205028.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
sonophotocatalysis
4-chloro-2-nitro phenol
photocatalysis
sonolysis
synergy
Opis:
The photocatalytic, sonolytic and sonophotocatalytic degradation of 4-chloro-2-nitrophenol (4C2NP) using heterogeneous (TiO2) was investigated in this study. Experiments were performed in slurry mode with artificial UV 125 watt medium pressure mercury lamp coupled with ultrasound (100 W, 33+3 KHz) for sonication of the slurry. The degradation of compound was studied in terms of first order kinetics. The catalyst concentration was optimized at 1.5 gL-1, pH at 7 and oxidant concentration at 1.5 gL-1. The results obtained were quite appreciable as 80% degradation was obtained for photocatalytic treatment in 120 minutes whereas, ultrasound imparting synergistic effect as degradation achieved 96% increase in 90 minutes during sonophotocatalysis. The degradation follows the trend sonophotocatalysis > photocatalysis > sonocatalytic > sonolysis. The results of sonophotocatalytic degradation of pharmaceutical compound showed that it could be used as efficient and environmentally friendly technique for the complete degradation of recalcitrant organic pollutants which will increase the chances for the reuse of wastewater.
Źródło:
Archives of Environmental Protection; 2013, 39, 2; 17-28
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phase Transitions and Stability of Group IV BCC Metals
Autorzy:
Verma, M. L.
Verma, A.
Rathore, R. P. S.
Powiązania:
https://bibliotekanauki.pl/articles/1968848.pdf
Data publikacji:
1998-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.Dc
Opis:
Born stability criteria were employed in the framework of extended generalised exponential potential to calculate the theoretical strength and range of stability of a perfect uniaxially stressed crystal lattice of group IV bcc metals: titanium, zirconium, and hafnium. The analysis depicts two ranges of stability, a bcc phase and a body centered tetragonal phase. The computed value of theoretical strength and strain of bcc Ti, Zr and Hf agree satisfactorily with the experimental limits. The second-order elastic constants C$\text{}_{11}$ and C$\text{}_{12}$ were also computed.
Źródło:
Acta Physica Polonica A; 1998, 93, 3; 479-489
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Nucleation on the Stability of BCC Metals
Autorzy:
Verma, A.
Verma, M. L.
Rathore, R. P. S.
Powiązania:
https://bibliotekanauki.pl/articles/1963285.pdf
Data publikacji:
1997-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.Dc
Opis:
Numerical calculations are made of theoretical strength and range of stability of a perfect uniaxially stressed crystal lattice of bcc vanadium, niobium and tantalum in the framework of extended generalised exponential potential by applying Born stability criteria. Two ranges of stability, a bcc phase and a body centered tetragonal phase are found to exist. The computed values of theoretical strength and strain of bcc V, Nb and Ta agree reasonably well with the experimental limits.
Źródło:
Acta Physica Polonica A; 1997, 91, 3; 583-596
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elastic Behaviour and Lattice Vibrations in bcc V and Nb
Autorzy:
Verma, A.
Verma, M. L.
Rathore, R. P. S.
Powiązania:
https://bibliotekanauki.pl/articles/1946133.pdf
Data publikacji:
1996-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Dj
62.20.Dc
Opis:
A model is developed by extending the generalised form of exponential potential known as extended generalised exponential potential to account for: (a) a realistic realization of interactions in all separations in general and that of small separations in particular, (b) three-body and electronic effects into the interaction in an alternative and simpler form, (c) a model free from usual fitting procedure. The model is employed to compute the cohesive energy, phonon spectra and second- and third-order elastic constants for group VA bcc metals V and Nb. The computed results showing good agreement with the experimental findings lend reliability and credibility to the potential.
Źródło:
Acta Physica Polonica A; 1996, 90, 3; 547-556
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lactoferrin gene promoter variants and their association with clinical and subclinical mastitis in indigenous and crossbred cattle
Autorzy:
Chopra, A.
Gupta, I.D.
Verma, A.
Chakravarty, A.K.
Vohra, V.
Powiązania:
https://bibliotekanauki.pl/articles/31066.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Lactoferrin (Lf) gene promoter was screened for the presence of single nucleotide polymphism in indigenous and crossbred cattle from North India and to evaluate its association with Mastitis. Study revealed the presence of genetic variation in regulatory region of bovine Lactoferrin gene using PCR-RFLP technique. Three genotypes namely GG, GH and HH were identified. A single nucleotide change, from guanine to adenine at 25th position was found to be significantly associated (p<0.05) with clinical mastitis in indigenous Sahiwal and crossbred Karan Fries cattle maintained at organised herd of National Dairy Research Institute, Karnal. A non-significant association was observed between subclinical mastitis, somatic cell score (SCS), and GG genotype in Karan Fries cattle, however, a lower SCS was observed in animals having GG genotype. Overall a lower incidence of clinical mastitis was recorded in those animals having GG genotype of Lf in Sahiwal and Karan Fries (KF) cattle. The SNP identified in the promoter region may effect expression lactoferrin protein, which may lead to different levels of antibacterial and anti- nflammatory activity of Lf gene. Results from this study indicated the probable role played by Lactoferrin promoter to serve as candidate gene for mastitis susceptibility among indigenous and crossbred milch cattle.
Źródło:
Polish Journal of Veterinary Sciences; 2015, 18, 3
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Discovering diagnostic gene targets for early diagnosis of acute GVHD using methods of computational intelligence on gene expression data
Autorzy:
Fiasch'e, M.
Morabito, F. C.
Verma, A.
Kasabov, N.
Cuzzola, M.
Iacopino, P.
Powiązania:
https://bibliotekanauki.pl/articles/91634.pdf
Data publikacji:
2011
Wydawca:
Społeczna Akademia Nauk w Łodzi. Polskie Towarzystwo Sieci Neuronowych
Tematy:
acute graft-versus-host disease
aGVHD
haematopoietic stem cell transplantation
HSCT
immunologic attack
diagnosis
computational intelligence
gene expression data
Opis:
This is an application paper of applying standard methods of computational intelligence to identify diagnostic gene targets and to use them for a successful diagnosis of a medical problem - acute graft-versus-host disease (aGVHD). This is the major complication after allogeneic haematopoietic stem cell transplantation (HSCT) in which functional immune cells of donor, recognize the recipient as ”foreign” and mount an immunologic attack. In this paper we analyzed gene-expression profiles of 47 genes associated with allo-reactivity in 59 patients submitted to HSCT. We have applied different dimensionality reduction techniques of the variable space, combined with different classifiers to detect the aGVHD at onset of clinical signs. This is a preliminary study which utilises both computational and biological evidence for the involvement of a limited number of genes for the diagnosis of aGVHD. Directions for further studies are also outlined in this paper.
Źródło:
Journal of Artificial Intelligence and Soft Computing Research; 2011, 1, 1; 81-89
2083-2567
2449-6499
Pojawia się w:
Journal of Artificial Intelligence and Soft Computing Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal analysis of epoxy based coconut fiber-almond shell particle reinforced biocomposites
Analiza cieplna biokompozytów epoksydowych umacnianych łuskami migdałowca i włóknami kokosowymi
Autorzy:
Chaudhary, A. K.
Gope, P. C.
Singh, V. K.
Suman, A. R.
Verma, A.
Powiązania:
https://bibliotekanauki.pl/articles/175615.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
biocomposites
almond shell
coconut fiber
microstructure
thermal analysis
biokompozyt
łuski migdałowca
włókno kokosowe
mikrostruktura
analiza cieplna
Opis:
In this research, the suitability of almond shell and coconut fiber as a renewable agricultural residue for manufacturing of biocomposite to be used as a replacement of wood was investigated. The use of agriculture waste as a reinforcement in composite may result in several environmental and socioeconomic benefits. Biocomposite containing different weight percentage of almond shell particle (10, 20, 30, 40 and 50 wt%) and coconut fiber (2, 4 and 6 wt%) mixed with 20 wt% of almond shell particles were made using epoxy resin and 0.5 wt% of Tricresyl Phosphate. Thermal stability test and morphology (SEM) of the biocomposite were determined.
W artykule przedstawiono analizę wyników badań trwałości materiałów biokompozytowych umacnianych łuskami migdałowca i włóknami kokosowymi, używanych jako zamienniki drewna. Zastosowanie odpadów rolniczych jako elementów umacniających materiały kompozytowe pozytywnie oddziałuje zarówno na środowisko naturalne, jak i kryteria ekonomiczne ich producentów. W badaniach stosowano materiały biokompozytowe o zawartości cząstek łusek migdałowca od 10 do 50% mas. oraz włókien kokosowych 2, 4 i 6% mas. Osnową wytworzonych kompozytów była żywica epoksydowa z dodatkiem fosforanu trikrezylowego 0,5% mas. Wykonano badania stabilności cieplnej wytworzonych biokompozytów oraz ich mikrostruktury przy zastosowaniu mikroskopu skaningowego SEM.
Źródło:
Advances in Manufacturing Science and Technology; 2014, 38, 2; 37-50
0137-4478
Pojawia się w:
Advances in Manufacturing Science and Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Plasmonic nano-imaging with metallic nanolens
Autorzy:
Ono, A.
Verma, P.
Kawata, S.
Powiązania:
https://bibliotekanauki.pl/articles/385208.pdf
Data publikacji:
2009
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
plasmonics
near-field optics
Opis:
We proposed a nano-imaging system at optical frequency region with the array of metallic nanorods. We simulated the field distribution of imaging process using the finitedifference time-domain algorithm. It is found that the spatial resolution is 40 nm, which is much beyond the diffraction-limit and is limited by the array pitch. The typical configuration is a hexagonal arrangement with 40 nm periodicity of silver rods of 50 nm height and 20 nm diameter. The image formation highly depends on the coherence and the polarization of the dipole sources, the array pitch, and the source-array distance. The principle of our near-field imaging is based on the longitudinal resonance of the localized surface plasmon along a metallic nanorod. The spectral responses of the device are also investigated.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2009, 3, 4; 102-104
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectroscopic Investigation of the Hair of Diabetic Patients
Autorzy:
Ali, A.
Verma, N.V.
Powiązania:
https://bibliotekanauki.pl/articles/412256.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
diabetes
metals
hair
AAS
Opis:
Diabetes is a major disease condition that is accountable for 5% of annual cause of death globally and it continues to escalate. In this research the levels of minerals in persons with type 2 diabetes were investigated using hair as the biopsy specimen. The philosophy behind is that minerals are involved in countless metabolic functions in all phases of the life process, an imbalance of which can have widespread implication, while hair due to its physiology serves an invaluable record of the body's exposure to minerals. Hair metal testing is a fascinating new diagnostic tool and often gives unexpected clues to mineral imbalances in the body. In executing the research samples of head hair collected from 6 type 2 diabetic patients were washed to remove exogenous contaminants, then subjected to open vessel acid digestion and subsequent analysis for the elements Ca, Cd, Cr, Cu Fe, K, Mg, Na and Zn using Flame Atomic Absorption Spectroscopy (FLAAS). After comparing the concentration of the elements to a range that is considered to be normal it was found that Ca, Zn, Fe, Mg, K, Cu, Cd and Cr were off range while Na was normal. Upon investigating the function and effects of the elements that were off range it was found that a deficiency of chromium and an excess of iron could be a possible cause of diabetes.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 3; 37-45
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photochemical studies of Eichhornia crassipes (Water Hyacinth)
Autorzy:
Ratan, A.
Verma, V. N.
Powiązania:
https://bibliotekanauki.pl/articles/412466.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Water Hyacinth
Eichhornia crassipes
AAS
Elements
metals
Opis:
Eichhornia crassipes is a floating macrophyte. It is capable of assimilating large quantities of toxic metals, some of which are essential for plant growth. Water Hyacinth grows rapidly in water with a high level of nutrients like nitrogen and phosphorous. The plants have been shown to absorb trace elements such as Silver (Ag), Lead (Pb), Cadmium (Cd) and Copper (Cu) reported by Lu et al [1]. The purpose of this study is to determine the distribution of heavy metals in different parts of the Water Hyacinth . Such a detail study has been taken for the first time. It is expected that the metal distribution within the plant species would be a representation of the concentration and distribution of the water in which it is found. Plants have the ability to accumulate non-essential and essential trace elements and this ability could be harnessed to remove pollutant metals from the environment. Aluminum, cadmium, calcium, copper, iron, lead, magnesium and zinc have been found in different amounts in roots, stems , leaves and flowers.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 11, 3; 214-222
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ectomycorrhizae of Tomentella badia: description and molecular identification
Autorzy:
Binder, A.
Persoh, D.
Yorou, N.S.
Verma, R.
Bassler, C.
Agerer, R.
Powiązania:
https://bibliotekanauki.pl/articles/67044.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Botaniczne
Opis:
Species within the genera Tomentella are among the most important ECM in forests. However, our knowledge about their functional characteristics is still rather limited. The ectomycorrhizae of Tomentella badia on Picea abies are described here in detail and compared to the non-identified ECM Piceirhiza obscura. A pseudoparenchymatous mantle formed by epidermoid cells is covered by heaps of epidermoid cells. This mantle type is regarded as a new one and designated as mantle type R. Many cells filled with dark blue contents and/or blue granules, together with clampless hyphae, are distinct characters of these ectomycorrhizae. Molecular-phylogenetic analysis of the ITS region was used for identification.
Źródło:
Acta Mycologica; 2013, 48, 2
0001-625X
2353-074X
Pojawia się w:
Acta Mycologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tabu search for shipping dangerous goods in a rail-truck network
Autorzy:
Zufferey, N.
Verma, M.
Powiązania:
https://bibliotekanauki.pl/articles/409393.pdf
Data publikacji:
2011
Wydawca:
Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
Tematy:
transport
koszty transportu
niebezpieczne towary
tabu search
intermodal transportation
dangerous goods
Opis:
The problem considered in this paper consists of planning and routing rail-truck intermodal shipments from a set of suppliers to a set of clients. The delivered quantities have to follow a truck-rail-truck intermodal path. There are three constraints to satisfy: the satisfaction of the demand is mandatory, each request should be delivered by its due date, and the capacity of a train cannot be exceeded. The objective function to minimize is a weighted summation of the cost and the risk. The former component concerns the fixed and variable transportation costs associated with trucks and trains, while the latter associated with dangerous goods is non-linear for trains. We propose a graph model to represent this problem and a tabu search metaheuristic to tackle it. Numerical experiments on realistic data are provided and discussed.
Źródło:
Research in Logistics & Production; 2011, 1, 3; 127-137
2083-4942
2083-4950
Pojawia się w:
Research in Logistics & Production
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular docking studies on the phytoconstituents as therapeutic leads against SARS-CoV-2
Molekularne badania dokujące nad zastosowaniem fitoskładników w terapii przeciw SARS-CoV-2
Autorzy:
Tiwari, Abhishek
Tiwari, Varsha
Verma, Navneet
Singh, Anita
Kumar, Manish
Saini, Vipin
Sahoo, Biswa Mohan
Kaushik, Deepak
Verma, Ravinder
Sagadevan, Suresh
Powiązania:
https://bibliotekanauki.pl/articles/2202611.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
Tematy:
Covid-19
spike glycoprotein
AutoDock Vina
Mpro
docking
artemisinin
withaferin A
glikoproteina kolca
dokowanie
artemizynina
witaferyna A
Opis:
Because of the present pandemic researchers are seeking for phytocandidates that can inhibit or stop SARS-CoV-2. The main protease (Mpro) of SARS-CoV-2 and spike glycoprotein (S) are both suppressed by bioactive compounds found in plants that work by docking them together. The Mpro proteins 6LU7 (complex with an inhibitor N3) and 5C3N (space group C2221) were employed in docking research. PyRx and AutoDock Vina software were used as docking engine. 22 identified phytoconstituents were selected from IMPPAT, a manually curated database, on the basis of their antiviral effects. Docking studies showed that phytoconstituents β-amyrin (-8.4 kcal/mol), withaferin A (-8.3 kcal/mol), oleanolic acid (-7.8 kcal/mol), and patentiflorin A (-8.1 kcal/mol) had the best results against 5C3N Mpro protein whereas kuwanon L (-7.1 kcal/mol), β-amyrin (-6.9 kcal/mol), oleanolic acid (-6.8 kcal/mol), cucurbitacin D (-6.5 kcal/mol), and quercetin (-6.5 kcal/mol) against 6LU7 Mpro protein. All the compounds were examined for their ADMET characteristics using SwissDock. Present research reports that the phytoconstituents along with docking score will be helpful for future drug development against Covid-19.
W związku z pandemią prowadzone są badania mające na celu znalezienie fitosubstancji, które mogą hamować lub zatrzymywać rozwój SARS-CoV-2. Działanie głównych białek proteazy (Mpro) SARS-CoV-2 i glikoproteiny kolca (S) jest osłabiane przez związki bioaktywne występujące w roślinach poprzez proces dokowania. Do badań dokujących użyto białka Mpro 6LU7 (kompleks z inhibitorem N3) i 5C3N (grupa przestrzenna C2221). Jako silnik dokujący zastosowano PyRx i AutoDock Vina. Zidentyfikowano 22 fitoskładniki wybrane z bazy danych IMPPAT, z uwzględnieniem ich działania przeciwwirusowego. Najbardziej skuteczne w przypadku białka Mpro 5C3N okazały się fitoskładniki β-amyryna (-8,4 kcal/mol), witaferyna A (-8,3 kcal/mol), kwas oleanolowy (-7,8 kcal/mol) i patentifloryna A (-8,1 kcal/mol), a w przypadku białka Mpro 6LU7 kuwanon L (-7,1 kcal/mol), β-amyryna (-6,9 kcal/mol), kwas oleanolowy (-6,8 kcal/mol), kukurbitacyna D (-6,5 kcal/mol) i kwercetyna (-6,5 kcal/mol). Wszystkie substancje zbadano pod kątem ich właściwości ADMET przy użyciu SwissDock. Wykazano, że fitoskładniki mogą być pomocne w pracach nad lekami przeciwko Covid-19.
Źródło:
Polimery; 2022, 67, 7-8; 355---374
0032-2725
Pojawia się w:
Polimery
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of atomic absorption spectroscopy to food sciences (A study on Persea americana Mill – Avocado)
Autorzy:
Verma, Vishwa N.
Powiązania:
https://bibliotekanauki.pl/articles/1182920.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
avocado
persea americana mill
aas
elemental analysis
element-concentration
Opis:
Our health is very much dependent to our balance meals. The body needs different kinds of minerals for its different functions. Keeping this idea in mind the spectroscopic study on Persea Americana Mill (Avocado Fruit) has been taken into account. The investigation shows that the avocado (Persea Americana Mill) is an ideal food for the balance of minerals in our body. The quantitative investigation using atomic absorption spectroscopic technique shows the presence of Ca, Cd, Co, Cu, Fe, Mg, Mn, Pb and Zn elements in seed (nut), leaf and flesh of avocado. The concentration of Ca and Mg were found very high in nut, leaf and flesh; out of which the concentration of Mg (100809 mg/Kg) was highest in leaf followed by flesh and nut.
Źródło:
World Scientific News; 2016, 49, 2; 104-116
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł

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