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排序方式: 共有127条查询结果,搜索用时 765 毫秒
51.
Moustafa A. Gouda Moged A. Berghot Ghada E. Abd El‐Ghani Abd El‐Galil M. Khalil 《Journal of heterocyclic chemistry》2016,53(4):1241-1250
One‐pot condensation of malononitrile 1 , furan‐2‐carbaldehyde 2 , butan‐2‐one 3 , and ammonium acetate in ethanol, followed by cyanoacetylation of the formed nicotinonitrile 4 with 3‐(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)‐3‐oxopropanenitrile 5 afforded the cyanoacetamide 6 . Compound 6 was used as a key intermediate for synthesis of nicotinonitriles via reaction with different reagents. 相似文献
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A thin film of polyflourene polymer was sandwiched between a conductive polymer deposited on silver nanowire and metal electrode to form a multilayer polymer‐based diode device. The electrical properties of fabricated polymeric diode have been studied by current–voltage method. The current–voltage characteristics of the fabricated device exhibited non‐ideal, asymmetrical, and rectifying behavior. Ohmic current conduction mechanism was observed in the device at low voltage. At higher voltage values, the space‐charge‐limited current conduction mechanism was found to be dominated. The values of the Schottky barrier height, ideality factor, and saturation current density were extracted according to the standard thermionic emission model and discussed. The barrier height and ideality factor were calculated as 0.72 eV and 2.53, respectively. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
54.
Engel R Ghani I Montenegro D Thomas M Klaritch-Vrana B Castaño A Friedman L Leb J Rothman L Lee H Capodiferro C Ambinder D Cere E Awad C Sheikh F Rizzo J Nesbitt LM Testani E Melkonian K 《Molecules (Basel, Switzerland)》2011,16(2):1508-1518
Cationic lipids have long been known to serve as antibacterial and antifungal agents. Prior efforts with attachment of cationic lipids to carbohydrate-based surfaces have suggested the possibility that carbohydrate-attached cationic lipids might serve as antibacterial and antifungal pharmaceutical agents. Toward the understanding of this possibility, we have synthesized several series of cationic lipids attached to a variety of glycosides with the intent of generating antimicrobial agents that would meet the requirement for serving as a pharmaceutical agent, specifically that the agent be effective at a very low concentration as well as being biodegradable within the organism being treated. The initial results of our approach to this goal are presented. 相似文献
55.
Muhammad Usman Ghani Muhammad Sagir Muhammad Bilal Tahir Sami Ullah Mohammed Ali Assiri 《International journal of quantum chemistry》2024,124(3):e27340
Halide base perovskite LiCdX3 (X = F, Cl) is tested by CASTEP (Cambridge Serial Total Energy Package) based on density function theory (DFT). The presented discussion is to explore the structural, electronic, and optical properties of LiCdX3 (X = F, Cl). The calculated values of the lattice parameter are found to be 3.8 Å and 5.27 Å of LiCdF3 and LiCdCl3 respectively. The ideal structure of LiCdX3 (X = F, Cl) is cubic and dynamically stable. Electronic properties show that materials are semiconductors. The results from band structure are further evaluated by the total and partial density of states. The partial and total density of states confirms the degree of localization of electrons. In optical properties, the highest absorption coefficient is observed in LiCdCl3. The material is half metallic and has a narrow indirect band gap which may be used in photovoltaic applications. 相似文献
56.
Reza Mohammadpour Aminuddin Ab. Ghani Hazi Mohammad Azamathulla 《Applied Mathematical Modelling》2013
Gabion weirs with optional design as a broad crested weirs are suitable structures to reduce flash flood with a minimal negative impact on the water environment. In the present study, the 3-D flow was simulated around gabion weirs with respect to free-surface water. The Reynolds-averaged Navier–Stokes equations are solved to predict water surface over the gabion weir. The VOF method with the geometric reconstruction scheme was applied to treat the complex free-surface flow. Simulations were performed using three variants of the k–ε and the RSM models to find the water level and velocity distribution profile and results are compared with several experimental data available in the literature. The structured mesh was used for all domains with high dense mesh near the solid region. A comparison between experimental data and simulations indicates that the k–ε model can be used to predict the complex flow and water level with high accuracy. 相似文献
57.
Fiber optic displacement sensors with bundled and fused coupler fiber probes are being investigated. The effects of axial
displacements on the detected output voltages are also investigated for fiber bundle probe sensor. The resolutions obtained
are 0.9 and 4.0 μm, for the front and back slopes, respectively. A comparison is made with a commercial plastic based multimode
fused coupler which gives a better range of 2.0 mm. This is longer than that achieved by the fiber bundle probe which is only
0.4 mm and has a lower resolution of 34 μm for the case of 50:50 coupling ratio. 相似文献
58.
Barbaran J. Hasani Tabasi M. Aragi M. R. Ghani Jangjo E. 《Crystallography Reports》2018,63(7):1200-1202
Crystallography Reports - Ce3+,Nd3+:YAG single crystal was grown by Czochralski method without using any reduction gas. The growth was done in the atmosphere of pure nitrogen. The limited-flow of... 相似文献
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Ahmad Z Mehmood S Fatima I Malik A Ifzal R Afza N Iqbal L Latif M Nizami TA 《Magnetic resonance in chemistry : MRC》2008,46(1):94-98
Salsolins A (1) and B (2), the new triterpenes, have been isolated from the chloroform soluble fraction of Salsola baryosma along with 2alpha,3beta,23,24-tetrahydroxyurs-12-en-28-oic acid (3) reported for the first time from this species. Their structures have been assigned from 1H and 13C NMR spectra, DEPT and by 2D COSY, NOESY, HMQC and HMBC experiments. The compounds 1-3 showed significant antioxidant activity. 相似文献