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21.
研究了带阻尼项一维非等熵流方程组的初边值问题,利用能量估计的办法证明了整体解的存在性和得到在L2-模及L∞-模意义下解的大时间状态稳定性估计。 相似文献
22.
23.
Development and Characterization of Metal-Insulator-Metal Capacitors with SiNx Thin Films by Plasma-Enhanced Chemical Vapor Deposition 下载免费PDF全文
We report the fabrication of high breakdown voltage metal-insulator-metal (MIM) capacitors with 200-nm silicon nitride deposited by plasma-enhanced chemical vapor deposition with 0.957 SiH4/NH3 gas mixing rate, 0.9 Torr working pressure, and 60 W rf power at 250℃ chamber temperature. Some optimized mechanisms such as metal source wiping, pre-melting and evaporation rate adjustment are used for increasing the yield of the MIM capacitors. N2 annealing and O2/H2 plasma pre-deposition treatment is proposed to increase the reliability of the MIM capacitors in high-temperature, high-pressure, and high-humidity environments. A 97% yield and up to 148 V breakdown voltage of a 13.06pF MIM capacitor with 0.04 mm^2 die area can be fabricated. 相似文献
24.
The nonlinear stochastic evolution equations have a wide range of applications in physics, chemistry, biology, economics and finance from various points of view. In this paper, the $\left({G^{\prime}}/{G}\right)$ -expansion method is implemented for obtaining new travelling wave solutions of the nonlinear (2?+?1)-dimensional stochastic Broer–Kaup equation and stochastic coupled Korteweg–de Vries (KdV) equation. The study highlights the significant features of the method employed and its capability of handling nonlinear stochastic problems. 相似文献
25.
Thermal analysis has been integrated into our physical chemistry laboratory course in order to allow students to systematically explore the role of composition in determining the physical properties of a binary mixture. The -naphthol/acetamide system is presented as an interesting starting point for such a project, as it displays a temperature/composition phase diagram which deviates slightly from the simple two-component eutectic picture. Students compare their measured pure-component melting temperatures with literature values, rationalize the observed trends with mixing using freezing-point-depression arguments, and make a literature search of the unique morphological solid phase obseved in analogous studies. This hands-on project is designed to be accompanied by a classroom discussion of multicomponent phase equilibria. 相似文献
26.
Nonlinear stochastic partial differential equations have a wide range of applications in science and engineering. Finding exact solutions of the Wick-type stochastic equation will be helpful in the theories and numerical studies of such equations. In this paper, Kudrayshov method together with Hermite transform is implemented to obtain exact solutions of Wick-type stochastic Korteweg–de Vries equation. Further, graphical illustrations in two- and three-dimensional plots of the obtained solutions depending on time and space are also given with white noise functionals. 相似文献
27.
KIM Mi-Ran SUH Bo-Ram KIM Jae-Gil KIM Young-Ho KIM Dae-Keun MOON Dong-Cheul 《高等学校化学学报》1999,20(Z1):190
Carpesium triste var. manshuricum K. is a plant which is rarely distributed in Korea, and it has long been used as traditional medicinal herb for its antipyretic, analgesic, vermifugic, insectifuge,pain-relief,and antiinflammatory properties. Several sesquiterpene lactones were isolated from the genus Carpesium. 相似文献
28.
A pentaammineazidocobalt(III) complex, [Co(NH3)5N3](MnO4)2XH2O has been synthesized by an one-pot synthesis method. It was characterized by studies such as infrared (IR) and UV-visible spectroscopy. The single crystal X-ray structure analysis revealed that the title complex crystallizes in space group Cc. The cobalt center is six coordinated with slightly octahedral geometry. The supramolecular architecture is also formed by intermolecular N-H…O (anion and H2O) and Mn-O…O-H hydrogen bonds. The binding property of the cation, [Co(NH3)5N3]2+ with the anion, MnO4– has also been determined (in solution phase) with the help of UV-visible spectroscopic titrations. Further, the genotoxic effects of KMnO4, [Co(NH3)5N3]Cl2 and [Co(NH3)5N3](MnO4)2XH2O were studied using Allium cepa root chromosomal aberration assay and it revealed that the genotoxicity of the newly synthesized complex is 1.97–1.76 fold, which is less compared to KMnO4. The order of genotoxic potential has been observed to be KMnO4 > [Co(NH3)5N3](MnO4)2XH2O > [Co(NH3)5N3]Cl2. 相似文献
29.
Sukkum Ngullie CHANG Jeong Jun LEE Hyun Jin KIM Sun Chul KANG 《Turkish Journal of Chemistry》2021,45(4):1155
Vitamin D2 (vit. D2) is a nutraceutical essentially needed for good health. However, it is susceptible to oxygen and high temperature. The use of natural products such as bioflavonoids possessing anti-degradative effect of vit. D2 degradation has not been described before. A combinational effect of vit. D2 with quercetin showed a positive effect and inhibited vit. D2 degradation when exposed to high temperature (50 ℃ and 75 ℃) at different time points. The results obtained revealed vit. D2 degradation was drastically increased with longer incubation under thermal treatment. However, quercetin and vit. D2 groups were able to significantly inhibit the degradation of vit. D2 and stabilize it, evaluated through the retention percentage. We also exposed vit. D2 at solutions with different pH values (1, 4, 5, 7, 10). Quercetin exerted vit. D2 anti-degradation at different pH values as well as under thermal pressure at different time points. Conclusively, quercetin can be an effective way to reduce temperature and pH induced degradation of vit. D2. 相似文献
30.
The effect of an applied magnetic field on an inhomogeneous superconductor is studied and the value of the upper critical magnetic field Hc3 at which superconductivity can nucleate is estimated. In addition, the authors locate the concentration of the order parameter, which depends on the inhomogeneous term a(x). Unlikely to the homogeneous case, the order parameter may concentrate in the interior of the superconducting material, due to the influence of the inhomogeneous term a(x). 相似文献