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51.
We present a numerical scheme for the calculation of incompressible three‐dimensional boundary layers (3DBL), designed to take advantage of the 3DBL model's overall hyperbolic nature, which is linked to the existence of wedge‐shaped dependence and influence zones. The proposed scheme, explicit along the wall and implicit in the normal direction, allows large time steps, thus enabling fast convergence. In order to keep this partly implicit character, the control volumes for the mass and momentum balances are not staggered along the wall. This results in a lack of numerical viscosity, making the scheme unstable. The implementation of a numerical diffusion, suited to the local zone of influence, restores the stability of the boundary layer scheme while preserving second‐order space accuracy. The purpose of this article is to present the analytical and numerical studies carried out to establish the scheme's accuracy and stability properties. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
52.
5-Chloroorsellinic acid inhibits the formation of penicillic acid by Penicillium cyclopium at sublethal concentrations. 相似文献
53.
Dr. Parameswara Rao Chinnam Birane Fall Dr. Dmitriy A. Dikin AbdelAziz Jalil Clifton R. Hamilton Stephanie L. Wunder Michael J. Zdilla 《Angewandte Chemie (International ed. in English)》2016,55(49):15254-15257
The preparation and characterization of the cocrystalline solid–organic sodium ion electrolyte NaClO4(DMF)3 (DMF=dimethylformamide) is described. The crystal structure of NaClO4(DMF)3 reveals parallel channels of Na+ and ClO4? ions. Pressed pellets of microcrystalline NaClO4(DMF)3 exhibit a conductivity of 3×10?4 S cm?1 at room temperature with a low activation barrier to conduction of 25 kJ mol?1. SEM revealed thin liquid interfacial contacts between crystalline grains, which promote conductivity. The material melts gradually between 55–65 °C, but does not decompose, and upon cooling, it resolidifies as solid NaClO4(DMF)3, permitting melt casting of the electrolyte into thin films and the fabrication of cells in the liquid state and ensuring penetration of the electrolyte between the electrode active particles. 相似文献
54.
Hepatitis C virus (HCV) is a major health problem across the world affecting the people of all age groups. It is the main cause of hepatitis and at chronic stage causes liver cirrhosis and hepatocellular carcinoma. Various therapeutics are made against HCV but still there is a need to find out potential therapeutics to combat the virus. The goal of this study is to identify the phytochemicals of Azadirachta indica leaves having antiviral activity against HCV NS3 protease through molecular docking and simulation approach. Results show that the compound 3-Deacetyl-3-cinnamoyl-azadirachtin possesses good binding properties with HCV NS3/4A protease. It can be concluded from this study that Deacetyl-3-cinnamoyl-azadirachtin may serve as a potential inhibitor against NS3/4A protease. 相似文献
55.
Suleman Muhammad Riaz Samia Jalil Rashid 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1193-1219
Journal of Thermal Analysis and Calorimetry - Magnetic nanoparticles (MNPs)-induced hyperthermia is capable of heating the tumor without side effects. In this technique, the tumor temperature is... 相似文献
56.
Soliman Yasser S. Alkhuraiji Turki S. 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(1):241-250
Ninhydrin reacts with alanine forming a Ruhemann’s purple (RP) compound. RP and chloral hydrate (CH) were introduced into gelatin to form a tissue equivalent RP gel for radiation dose measurements, 5–450 Gy. The gel color fades proportionally with the absorbed dose. Addition of CH to the gel improved its radiation sensitivity and fading. RP was analyzed by FTIR spectrometer and the gel by UV–Vis spectrophotometer at 404 and 572 nm. Dose–response is nearly temperature independent from 22 to 30 °C but it is a time dependent after irradiation. Uncertainty (2σ) in dose estimation is less than 6.0%.
相似文献57.
We present an analogy between the classic gambler's ruin problem and the thermally activated dynamics in periodic Brownian ratchets. By considering each periodic unit of the ratchet as a site chain, we calculated the transition probabilities and mean first passage time for transitions between energy minima of adjacent units. We consider the specific case of Brownian ratchets driven by Markov dichotomous noise. The explicit solution for the current is derived for any arbitrary temperature, and is verified numerically by Langevin simulations. The conditions for current reversal in the ratchet are obtained and discussed. 相似文献
58.
Heat transfer coefficients for quenching in water have been measured as a function of temperature using steel probes for a
variety of iron alloys. The coefficients were derived from measured cooling curves combined with calculated heat-capacities.
The resulting data were then used to calculate cooling curves using the finite volume method for a large steel sample and
these curves have been demonstrated to be consistent with measured values for the large sample. Furthermore, by combining
the estimated cooling curves with time-temperature-transformation (TTT) diagrams it has been possible to predict the variation
of hardness as a function of distance via the quench factor analysis. The work should prove useful in the heat treatment of
the steels studied, some of which are in the development stage. 相似文献
59.
An efficient and practical procedure for direct synthesis of 3,5‐diaryl‐1,2,4‐thiadiazoles by thioamides with 2,4,6‐trichloro‐1,3,5‐triazine (TCT) and dimethylsulfoxide using 1‐butyl‐3‐methylimidazolium tetrafluoroborate as an eco‐friendly reaction medium under ambient temperature is described. This protocol can be considered as a new procedure for 3,5‐diaryl‐1,2,4‐thiadiazoles synthesis. J. Heterocyclic Chem., (2010). 相似文献
60.
Hosseinzadeh R Tahmasebi R Farhadi K Moosavi-Movahedi AA Jouyban A Badraghi J 《Colloids and surfaces. B, Biointerfaces》2011,84(1):13-17
Ion pair of cationic surfactant (cetytrimethylammonium bromide) and tungestosilicic acid incorporated in PVC matrix, was used for coating a piece of copper wire as a new high sensitive SPME fiber in extraction and determination of BTEX compounds from the headspace of water samples prior to GC/FID analysis. Under optimum extraction conditions, limits of detection for benzene, toluene, ethylbenzene, p-xylene, m-xylene and o-xylene were found to be 1.18, 5.61, 0.87, 0.29, 0.22 and 0.33 ng L(-1) respectively. Low detection limits, wide linear dynamic ranges, good reproducibility (RSD% 1.48-4.27), high fiber capacity and high mechanical durability are some of the most important advantages of the new fiber. 相似文献