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Wyszukujesz frazę "Ahmed, A." wg kryterium: Autor


Tytuł:
Investigation on the structural, optical and topographical behavior of Cadmium oxide polycrystalline thin films using electrochemical depositing method at different times
Autorzy:
Abd, Ahmed N.
Dawood, Mohammed O.
Hassoni, Majid H.
Hussein, Ali A.
Powiązania:
https://bibliotekanauki.pl/articles/1192094.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Cadmium oxide
thin film
optical characteristics of film
electrochemical depositing method
Opis:
The optical and structure properties of Cadmium oxide (CdO) thin film prepared by electrochemical deposition method at different times (15, 30 and 60) min were investigated in this paper. Results of optical Transmission, absorption, reflection spectra, optical conductance, refractive index, extension coefficient, real and imaginary dielectric constants studies are reported. The optical transmittance of the CdO thin film which formed at room temperature was 20% at wavelength ≈350 nm then increases to 60% at wavelength ≈1100 nm for thin film of CdO. The band-gap was also calculated from the equation relating absorption coefficient with the wavelength. The energy band gap changes from 2.3eV (Bulk CdO) to 2.45eV (CdO thin film). The plotted graphs show the optical characteristics of the film which varied with the wavelength and the photon energy. The optical conductance and band-gap indicated that the film is transmitting within the visible range. The dielectric constant and optical conductance of the film initially decreases slowly with increase in photon energy. The extinction coefficient and refractive index of the films also evaluated, which affected with the change in transmittance. The structure of synthesised CdO thin film was analyzed by X-ray diffraction XRD which revealed that the CdO thin film are polycrystalline and have several peaks of cubic face structure. The crystallite size, dislocation density, microstrain and number of dislocations of the thin film were calculated and listed.
Źródło:
World Scientific News; 2016, 37; 249-264
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seed Quality and Protein Classification of Some Quinoa Varieties
Autorzy:
Abd El-Hakim, Ahmed F.
Mady, Emad
Abou Tahoun, Ayman M.
Ghaly, Mohammed S. A.
Eissa, Mohamed A.
Powiązania:
https://bibliotekanauki.pl/articles/2025743.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
quinoa
seed vigour
seed quality
amino acids composition
agro-climatic zone
Opis:
Quinoa plants, originating from the Andean mountains in South America, have a large scale of biological diversity. Along with the cultivation favorableness of quinoa, it reveals superior nutrition aspects. In comparison with cereal crops, like rice, maize, and wheat, quinoa seeds contain valuable quantities of protein of remarkable quality. The current study compared four quinoa cultivars from different origins in terms of protein composition and germinability. In addition, this study focused on the effect of different geographical cultivation areas on the protein composition of wild Egyptian quinoa seeds and three other cultivars that vary in their cultivation origins. Significant differences were observed among the quinoa varieties in the germination percentage (GP), shoot length (SL), and root length (RL). Using the technology of Near-InfraRed Spectroscopy, the highest protein value was recorded for the American variety (18.39%), followed by the Wild Egyptian variety (17.16%). The aromatic phenylalanine recorded the highest concentration of the essential amino acid bulk. The Rainbow variety contained 12.7 g-aa/kg protein, followed by the wild Egyptian variety with 4.9 g-aa/kg protein. In turn, glutamic was the most abundant amino acid of the non-essential amino acids, with 10.1, 4, 23.4, and 4 (g-aa/kg protein) for quinoa varieties, Wild Egyptian, American, Rainbow, Black, respectively. SDS-PAGE was used to identify the allelic variations in the seed storage protein profiles among the studied quinoa varieties. The studied quinoa varieties showed 23.81% of the polymorphism in the protein bands, with the mean band frequency of 0.881. The resulting protein bands fluctuated in the range between 115.02 and 16 kDa. With a similarity percentage (90%), Wild Egyptian and the Rainbow quinoa varieties can be classified in one clade.
Źródło:
Journal of Ecological Engineering; 2022, 23, 1; 24-33
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exploitation of industrial solid wastes for preparing zeolite as a value-added product and its kinetics as adsorbent for heavy metal ions
Autorzy:
Abdel-Hameed, Reham Mohamed
Abdel-Aal, Elsayed A.
Farghaly, Fatma E.
Ibrahim, Ibrahim A.
Abdel Khalek, Mohamed A.
Ahmed, Mohamed A.
Abdel-Messih, Micheal F.
Powiązania:
https://bibliotekanauki.pl/articles/1448799.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
zeolite P
aluminium wastes
hydrothermal process
metal ion removal
aluminum waste
Opis:
Aluminum and fumed silica as solid industrial wastes were converted to zeolite NaPas a value-addedproduct without any template. The hydrothermal process was optimized using static autoclave. The crystallization was carried out at 100, 120 and 150°C for 24, 48 and 72 h. The prepared zeolite of Si:Al ratio of 1.2 was characterized using X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) provided with Energy Dispersive Spectroscopy (EDS), Surface Area, Fourier Transmitted Infra-Red (FTIR) and Thermal Analysis (TG-DSC). The crystalline phase was formed at 100°Cafter 72 hours and at 120°C after 48 hours, while it was formed after 24 honlyat 150°C. Increasing temperature and time lead to the conversion of the prismatic gibbsite crystals into plate-like structure of zeolitewhich is then formedcauliflower-like structure.The prepared zeolite was employed as adsorbent for $Ni^{2+}$ and $Cu2+ions from aqueous solution.The kinetic studies of adsorption processes were performed.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 1; 87-99
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design, Synthesis and Biological Evaluation of Novel Benzo[4,5]thiazolo[2,3-c][1,2,4]triazole Derivatives as Potential Anticancer Agents
Autorzy:
Abdelazeem, Ahmed H.
Gouda, Ahmed M.
Omar, Hany A.
Alrobaian, Majed
Powiązania:
https://bibliotekanauki.pl/articles/895393.pdf
Data publikacji:
2018-06-30
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
apoptosis
anticancer
S-benzothiazolotriazole
Kinase
caspase3/7
Opis:
In the present study, we have designed and synthesized a novel series of benzothiazolotriazole derivatives as potential anticancer agents. The anticancer activity of the newly synthesized compounds was evaluated against three cancerous cell lines; A549 (human lung adenocarcinoma), MCF-7 (human breast carcinoma) and Hep3B (human hepatocellular carcinoma) using MTT assay. Among this series, compounds 15 and 16 showed the most promising anticancer activity with IC50 values between 11.1 to 21.5 μM. Kinase profiling was performed for the most potent compounds 15 and 16 and it revealed weak inhibitory activity against 10 various kinases, where the highest inhibition was against CDK2/Cyclin A1 by compound 15. Furthermore, caspase-3/7 assay also indicated that the same compound 15 has the ability to induce apoptosis through the activation of effector caspase-3/7 family. Therefore, it could be deduced that the S-benzo[4,5]thiazolo[2,3-c][1,2,4]triazole is a promising novel anticancer scaffold with antiproliferative and apoptosis-inducing activities deserves to be taken up as a lead for further structural optimization.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2018, 75, 3
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical model to determine the Porosity and refractive index of porous silicon type-n by using Atomic force microscope
Autorzy:
Abdulridha, Wasna'a M.
Abd, Ahmed N.
Dawood, Mohammed O.
Powiązania:
https://bibliotekanauki.pl/articles/1193012.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Atomic Force Microscope
Porous silicon
n-PS
porosity
refractive index
thickness
Opis:
Porous silicon (PS) layer was produced by photochemical etching process at (5, 7, 10, 12 and 15) etching time and 7 mA/cm2 current density then after investigation by Atomic Force Microscope (AFM) the thickness of PS layer from about 3.4 µm to 15.8 µm was determined. The surface of porous silicon is formed from small pyramids with porous structure, where the porosity of n-PS is from ≈ (32-72%). Porous silicon layer formed on the silicon substrates by photochemical etching contains also the nanopores with diameter about (16.41-42) nm in current density (7mA/cm2). The porosity and thickness was determined from AFM results and compared with the result from the usually measured porosity and thickness through a gravimetric method we found that the values of porosity and thickness calculated from two methods are approximately similar to each other with few difference, the influence of structure changes on optical properties such as refractive index, which decreases exponentially with porosity.
Źródło:
World Scientific News; 2016, 28; 29-40
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
CdO thin films Grown by Chemical Spray Pyrolysis and Effect of Substrate type on its Optical Properties
Autorzy:
Abood, Mohmood Muwafaq
Jabbar, Wasmaa Abdulsattar
Daroysh, Hassan Hadi
Qader, Kameran Yasseen
Al-Baidhany, Ismaeel A.
Hussin, Hadi Ahmed
Jasim, Marwah Nasif
Powiązania:
https://bibliotekanauki.pl/articles/1194135.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
CdO
Optical properties
Thin Film
energy gap
Opis:
Cadmium oxide (CdO) thin films were formed by chemical spray pyrolysis technique for different substrate type (glass, quartz, ITO). Absorption spectra were recorded from UV-Visible spectrophotometer in the range of 300-900 nm. The absorbance increased when the glass substrate replaced to quartz or ITO substrate, also this behavior for absorption coefficient and extinction coefficient. While the refractive index tack unstable behavior. The energy gap decreased from 2.4 eV for CdO thin film deposited on glass substrate to 2.36 eV for CdO thin film deposited on ITO substrate.
Źródło:
World Scientific News; 2016, 57; 41-47
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of wood-derived biochar on the hydraulic characteristics of compacted soils: Its influence on simulated farmland carbon sequestration
Autorzy:
Ahmed, A.
Kurian, J.
Satyanarayana, S.
Raghavan, V.
Powiązania:
https://bibliotekanauki.pl/articles/2083067.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
soil biochar mixture
water retention
pore-size
distribution
hydraulic conductivity
carbon sequestration
Opis:
The addition of biochar is often proposed to increase agricultural soil quality and crop yield, while at the same time sequestering carbon from the atmosphere to help mitigate global climate change. In this research, the pore-size distribution, and saturated hydraulic conductivity of sandy loam and clay loam soils amended with varying dosages (0-10% dry basis) and two different particle sizes (0.5-420 μm (PS1) or 421-841 μm (PS2)) of wood-derived biochar were investigated under compacted conditions (5, 10, or 15 standard Proctor rammer blows (5B, 10B, or 15B, respectively)). In the 5B compacted SL (SL-5B) soil, the volume of the soil fissures and transmission pores decreased, while the volume of the storage pores (SP) increased with increasing wood-derived biochar dosage. 23.1±0.9% of the volume of the 5B compacted clay loam (CL-5B) are storage pores, this value increased to 27.4±2.0% upon amendment with 10% PS1. The saturated hydraulic conductivity of the sandy loam-5B soil amended with 10% PS1 decreased from 6.8±0.3 to 0.80±0.03 mm h-1. The sandy loam farmland C emissions decreased by 0.071 tC ha-1 y-1, whereas CL farmland C emissions decreased by 0.091 tC ha-1 y-1.
Źródło:
International Agrophysics; 2021, 35, 2; 167-177
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sequential Pattern Discovery Algorithm for Malaysia Rainfall Prediction
Autorzy:
Ahmed, A.
Bakar, A.
Hamdan, A.
Syed Abdullah, S.
Jaafar, O.
Powiązania:
https://bibliotekanauki.pl/articles/1402374.pdf
Data publikacji:
2015-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
92.40.Zg
92.60.Wc
Opis:
This study proposes a sequential pattern mining algorithm to discover sequential patterns of Malaysia rainfall data for prediction. The apriori based algorithm is employed to find the sequential patterns from the time series data. The frequent episodes of rainfall sequences are discovered and classified by the expert into four main events namely, No rain, Light, Moderate and heavy. The sequential rules of ten rainfall stations from the duration of 33 years are analysed. The proposed algorithm is able to generate higher confidence and support of frequent and sequential patterns. Generally, the proposed study has shown its potential in producing methods that manage to preserve important knowledge and thus reduce information loss in weather prediction problem.
Źródło:
Acta Physica Polonica A; 2015, 128, 2B; B-324-B-326
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Servo tracking of targets at sea
Autorzy:
Ahmed, A.
Brdyś, M. A.
Powiązania:
https://bibliotekanauki.pl/articles/908404.pdf
Data publikacji:
2006
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
śledzenie celu
urządzenie śledzące
filtr Kalmana
adaptacyjny układ sterowania
target tracking
tracker
Kalman filter
adaptive control
Opis:
This paper details a proposal for the position control system of a two-axis ship-mounted tracker. Aspects of the non-linear dynamics governing Line-Of-Sight (LOS) errors between the tracker and the target are presented. It is shown that the regulation of LOS errors can be achieved by introducing a feed-forward term based on the target’s velocity. This velocity is not measurable, and an estimator is required. Given that the tracking problem is non-linear, the classical separation principle does not hold, and cascading the estimator and regulator together may not lead to an optimal position control system. The ‘LQAdaptive’ system proposed here aims therefore to improve conformity to the separation principle. Simulation trials show that tracking is improved under the LQAdaptive system in comparison to a simple estimator-regulator structure.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2006, 16, 2; 197-207
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extended results of the Hadamard product of simple sets of polynomials in hypersphere
Autorzy:
Ahmed, A. El-Sayed
Powiązania:
https://bibliotekanauki.pl/articles/746574.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Basic sets of polynomials
Hadamard product
several complex variables
Opis:
In this paper we study some extended results of the Hadamard product set for several simple monic sets of polynomials of several complex variables in hyperspherical regions, then we obtain the effectiveness conditions for this Hadamard product in hyperspherical regions.
Źródło:
Commentationes Mathematicae; 2006, 46, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Consequences of Mercury Used by Artisanal and Small-Scale Gold Mining Processes a Case of River Nile State Sudan
Autorzy:
Ahmed, Ali M.A.
Purwanto, Purwanto
Sunoko, Henna Rya
Powiązania:
https://bibliotekanauki.pl/articles/124413.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
artisanal gold mining
small-scale gold mining
workers occupationally exposed
WOE
residents in surrounding communities
RSC
distribution of mercury concentration
surface soil
surface water
meteorological factors
topographical factors
Opis:
On the discovery of gold reserves in 14 states in Sudan, traditional gold mining suddenly started to flourish and hundreds of thousands of laymen became engaged in gold extraction. The new source of revenue generation added much to the empty treasury and the loss in petroleum revenue due to cessation of the south in 2011 could thus be compensated. Since gold extraction by artisanal and small-scale gold mining does not require much finance or advanced technology, it suited unskilled workers and many young people found their way into the new business. Although gold extraction generates high revenues, the use of mercury in gold extraction poses much threat to the environment and general health of miners and the surrounding areas. The research tries to investigate the effects of traditional gold mining in Alebedia area, Berber Locality in the River Nile State. The investigation includes A/ the effects of extraction methods on the environment and general health. B/ the level of education and its distribution within the miners and how it affected the awareness of the miners about the dangers of mining activities. C/ the period of stay that miners spend in the mining area its contribution on the awareness about the dangers and diseases inflicted on the miners, D/ the effects of traditional gold mining activities on natural environmental impacts and E/ the effects of the meteorological and topographical factors, the distribution and concentration of mercury in the area and their effects on the environment and general health. The research adopted the techniques of using random sampling and quantitative qualitative in addition to the analytical techniques. The research finally concluded that traditional gold mining has positive effects on the economic side and negative effects on the environment and general health.
Źródło:
Journal of Ecological Engineering; 2019, 20, 2; 106-115
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of Some Inorganic Anions and Organic Compounds as Corrosion Inhibitors of Cu-Zn Alloys in H2SO4 and HNO3 Solutions
Autorzy:
Ahmed, Amal S. I.
Ghanem, Wafaa A.
Hussein, Walaa A.
Gaber, Ghalia A.
Powiązania:
https://bibliotekanauki.pl/articles/351226.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cu-Zn alloys
oxy-acid solution
inhibition efficiency
inorganic anions
organic compounds
Opis:
Evaluation of inorganic and organic compounds as corrosion inhibitors of Cu-Zn alloys in H2 SO4 and HNO3 solutions was studied using potentiodynamic and impedance spectroscopy along with scanning electron microscope (SEM) and energy dispersive X-Ray analyzer (EDX) investigations. The corrosion inhibition of Cu-Zn alloys was investigated in oxy acid solutions using inorganic potassium permanganate and di-hydrogen phosphate, amino acids as environmentally safe materials, commercial cooling water, and green tea extracts. Both potassium permanganate and di-hydrogen phosphate improve the corrosion resistance of Cu-Zn alloys. Phosphate appears more effective as corrosion inhibitor for Cu-Zn alloys than permanganate. The inhibition efficiency (IE%) of the different amino acids such as valine, leucine and lysine was also calculated. The experimental results have shown that amino acid-like lysine can be used as an efficient corrosion inhibitor for the Cu-Zn alloys in oxy acid solutions. This may be due to the presence of two amino groups adsorbed together. For lysine, inhibition efficiency, IE%, of ~87 and ~59 is for H2SO4 and ~96.3 and 54.9 for HNO3 for alloy I and II respectively are observed. Due to the composition of green water have a great effect on the inhibition action on Cu-Zn alloys which reaching 91.8 and 96.5% for Alloy I and 95.4 and 87.1% for Alloy II in 0.5 M H2 SO4 and HNO3 respectively. Although benzotriazole, in cooling water, is an excellent inhibitor suitable for use in a wide variety of environments, it has toxic properties. So, much of the recent researches have focused on formulating new and more environmentally acceptable preservation solutions. The green tea, as plant extract, will be very environmentally friendly. The EDX confirm the formation of a protective layer on the Cu-Zn alloys containing aluminum in Alloy II. This sequence reflects the beneficial effects of Al in Alloy II. The presence of 2.43% Al in Alloy II improves the corrosion resistance due to the formation of thin, transparent, stable and self-healing Al2 O3 layer. This confirmed the results obtained from the potentiodynamic polarization measurements and EIS methods.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 2; 639-651
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Risk factors for futile tracheostomy: an analysis of the NIS database
Czynniki ryzyka daremnej tracheostomii: analiza bazy danych NIS
Autorzy:
Ahmed, Amin Mohamed
Arishi, Abdulaziz A
Loss, Lindsey
Parsikia, Afshin
Ortiz, Jorge
Powiązania:
https://bibliotekanauki.pl/articles/1033285.pdf
Data publikacji:
2020
Wydawca:
Towarzystwo Pomocy Doraźnej
Tematy:
Critical care
complication
mortality
risk factors
tracheostomy
Opis:
INTRODUCTION: Respiratory insufficiency and failure are leading causes of ICU admissions. Advances in medical technology allow prolonging of survival in critical illnesses. Hence, more tracheostomies are being performed. However, we are limited in predicting who may actually benefit. Our goal was to determine prognostic indicators of early mortality after tracheostomy in order to avoid futile procedures. MATERIAL AND METHODS: We performed a retrospective cohort study utilizing the National Inpatient Sample (NIS) database on all adults who underwent tracheostomy between 2005 and 2015. We defined futile tracheostomy as death within 30 days post tracheostomy during the same hospital admission. Univariate and multivariate testing were performed on the weighted dataset. Odds ratios (OR) were calculated with multivariate logistic regression testing. RESULTS: 851,020 cases met the inclusion criteria. Rate of futility was 12.4% (n=105,658). Total hospitalization cost was greater in the futile group as compared to non-futile group. On Multivariate testing, male gender, age greater than 65, 3 Elixhauser mortality index categories, Asian/Pacific Islander and other race, self-pay and no charge insurance, septicemia and mechanical ventilation greater than 96 hours were independent risk factors to predict futility. Among these, septicemia was the greatest risk for futility (OR 2.32), followed by Elixhauser mortality index >10 (OR 1.954), and Elixhauser mortality index between 3 and 10 (OR 1.468). CONCLUSIONS: Between 2005 and 2015, 12.4% of tracheostomies could be considered futile. Targeted efforts are needed to decrease the number of unnecessary procedures in the critically ill. We should consider the identified risk factors to share more informed discussions with patients and families to set better long-term expectations and realistic goals for care.
WSTĘP: Zapaść krążeniowa i niewydolność oddechowa są głównymi przyczynami przyjęć na OIT. Postęp technolgii w medycynie pozwala na przedłużenie życia w stanach krytycznych. W związki z tym wykonuje się więcej zabiegów tracheostomii. Jednak istnieją ograniczenia w określeniu kto powinien być faktycznie poddany zabiegowi. Celem autorów było określenie prognostycznych wskaźników wczesnej śmiertelności po tracheostomii, aby uniknąć daremnych zabiegów. MATERIAŁ I METODY: Przeprowadzono retrospektywne badanie kohortowe z wykorzystaniem National Inpatient Sample (NIS) - bazy danych osób dorosłych, którzy przeszli tracheostomię w latach 2005–2015. Daremną tracheostomię określilono jako śmierć w ciągu 30 dni po tracheostomii podczas tego samego przyjęcia do szpitala. Testy jednowymiarowe i wielowymiarowe były przeprowadzane na ważonym zbiorze danych. Ilorazy szans (OR) obliczono za pomocą wieloczynnikowych testów regresji logistycznej. WYNIKI: 851,020 przypadków spełniło kryteria włączenia. Wskaźnik daremności wyniósł 12.4% (n = 105,658). Całkowity koszt hospitalizacji był większy w grupie daremnej w porównaniu z grupą nie-daremną. W testach wielowymiarowych, płeć męska, wiek powyżej 65, trzy kategorie wskaźnika śmiertelności Elixhausera, rasy azjatyckie / wyspiarskie i inne rasy, samodzielne i bezpłatne ubezpieczenie, posocznica i wentylacja mechaniczna dłuższa niż 96 godzin były niezależnymi czynnikami ryzyka, które wskazywały na daremność. Pośród tych przypadków posocznica była największym ryzykiem daremności (OR 2.32), a następnie wskaźnik śmiertelności Elixhausera > 10 (OR 1.954), oraz Wskaźnik śmiertelności Elixhausera między 3 a 10 (OR 1.468). WNIOSKI: W latach 2005-2015 12.4% tracheostomii można uznać za daremne. Ukierunkowane wysiłki są potrzebne do zmniejszenia liczby niepotrzebnych zabiegów u osób w stanie krytycznym. Powinniśmy wziąć pod uwagę zidentyfikowane czynniki ryzyka, aby dzielić się bardziej świadomymi dyskusjami z pacjentami i rodzinami w celu ustalenia lepszych i realistycznych długoterminowych oczekiwań opieki.
Źródło:
Critical Care Innovations; 2020, 3, 3; 1-12
2545-2533
Pojawia się w:
Critical Care Innovations
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Verify the plasma parameters generated from the Tin material using the laser-induced plasma technique
Autorzy:
Ahmed, Baida M.
Aadim, Kadhim A.
Khalaf, Madyan A.
Powiązania:
https://bibliotekanauki.pl/articles/1030607.pdf
Data publikacji:
2020
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Laser-Induced Plasma (LIP)
Nd:YAG laser
Optical Emission Spectroscopic (OES)
Tin (Sn)
Opis:
In this work, A spectroscopic research on laser-produced tin plasma using optical emission spectroscopy (OES) technology is provided. Laser-induced Sn plasma produced at various laser energy has also been defined by visible emission spectroscopy. Plasma is created by a solid tin object radiated by a pulsed laser in a room environment. A Nd:YAG laser pulse 9 ns in duration with wavelength of 1064 nm and a focal length of 10 cm in the range of energy 500-800 mJ is used to generate plasma from a planar Sn sample. The electron temperature (Te) was calculated in ratio line intensities method, while the electron density (ne) was calculated using Saha-Boltzmann equation, also another plasma parameters was calculated such as plasma (fp), Debye length (λD) and Debye number (ND). The increase in electron temperature and density was observed as a function of laser energies. Measurement of the production of the electron temperature in the rang 0.926-0.952 eV, While the electron density is in the rang (1.9×1015-2.5×1015) cm-3.
Źródło:
World Scientific News; 2020, 144; 326-337
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental investigation on performance of a spark ignition engine runs with alcoholic blend-gasoline
Autorzy:
Ahmed, H. A.
Powiązania:
https://bibliotekanauki.pl/articles/243048.pdf
Data publikacji:
2015
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
methanol
ethanol
butanol
compression ratio
specific fuel consumption
exhaust gas temperature
performance
Opis:
In this paper performance resulted from a single cylinder spark-ignition engine fuelled with 20% by volume of methanol, ethanol, and butanol was studied and compared to gasoline. The experiments were conducted at variable speed and maximum torques. The conditions of stoichiometric air–fuel ratio at wide-open throttle were used. The tests were perfumed at higher useful compression ratio of the used Iraqi gasoline. The test results show that the higher compression ratio for the tested gasoline was 7.5:1. So an Iraqi conventional gasoline has engine HUCR=7.5:1 and its OST= 19 ºBTDC, this compression ratio can be considered low. Adding 20% of alcoholic blends by volume to gasoline improved the engine performance. Within the tested speed range, alcoholic blends produced higher brake powers, volumetric efficiency and thermal efficiency. In addition, it resulted in lower exhaust gases temperatures. The brake specific fuel consumption of the tested alcoholic blend was higher than that for gasoline.
Źródło:
Journal of KONES; 2015, 22, 3; 249-256
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł

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