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41.
In this paper, we present the local discontinuous Galerkin method for solving Burgers’ equation and the modified Burgers’ equation. We describe the algorithm formulation and practical implementation of the local discontinuous Galerkin method in detail. The method is applied to the solution of the one-dimensional viscous Burgers’ equation and two forms of the modified Burgers’ equation. The numerical results indicate that the method is very accurate and efficient. 相似文献
42.
采用电沉积法获得了接近化学计量比的贫铜和富铜的Cu(In1-xGax)Se2(CIGS)预置层,研究比较了两种预置层及其硒化处理后的成分和结构特性.得到了明确的实验证据证明,硒化后富铜薄膜中的CuxSe相会聚集凝结成结晶颗粒分散在表面.研究表明:在固态源硒化处理后,薄膜成分基本不变;当预置层中原子比Cu/(In+Ga)<11时,硒化后薄膜表面存在大量的裂纹;而当Cu/(In+Ga) >12时,可以消除裂纹的产生,形成等轴状小晶粒;富铜预置层硒化时蒸发沉积少量In,Ga和Se后,电池效率已达到68%;而贫铜预置层硒化后直接制备的电池效率大于2%,值得进一步深入研究.
关键词:
1-xGax)Se2薄膜')" href="#">Cu(In1-xGax)Se2薄膜
电沉积
硒化处理
贫铜或富铜薄膜 相似文献
43.
Bin Wang Yang-Bai Zhang Guo-Qiang Li Hua-Shi Guan Guo-Zhong Tong 《Chromatographia》2009,70(5-6):811-816
For the first time a validated liquid chromatography method coupled with hierarchical clustering analysis has been developed for the study of fingerprint chromatograms of extracts from the Radix Glehniae of Glehnia littorali. Liquid chromatography with gradient elution was performed on extracts from 23 plant samples collected from different geographical locations. Ten of twenty-three plant samples were selected using hierarchical clustering analysis and employed to establish the fingerprint. The fingerprint was established and ten chromatographic peaks were selected as characteristic peaks and panaxynol was used as reference standard compounds. The fingerprint chromatograms had a good stability, precision, and reproducibility. This method is a very reliable and useful method for assessment of the quality of Radix Glehniae. 相似文献
44.
Approximate analytic solutions for a generalized Hirota—Satsuma coupled KdV equation and a coupled mKdV equation 下载免费PDF全文
<正>This paper applies the variational iteration method to obtain approximate analytic solutions of a generalized Hirota-Satsuma coupled Korteweg-de Vries(KdV) equation and a coupled modified Korteweg-de Vries(mKdV) equation. This method provides a sequence of functions which converges to the exact solution of the problem and is based on the use of the Lagrange multiplier for the identification of optimal values of parameters in a functional.Some examples are given to demonstrate the reliability and convenience of the method and comparisons are made with the exact solutions. 相似文献
45.
与羟基配位是金属离子的一种重要的存在形式. 我们得到了两种半乳糖醇氯化钆配合物, 其中一种为金属离子与配体为2:1的配合物,钆离子与半乳糖醇的三个羟基及六个水分子配位, 其它水分子以结晶水的形式存在, 氯离子不参加配位;另一种配合物根据红外, 元素分析, 差热热重, 远红外以及太赫兹光谱推测可能是钆离子与两个半乳糖醇分子的六个羟基以及三个水分子配位, 形成1:1配合物. 实验结果说明半乳糖醇与稀土离子之间可以形成多种配合物, 金属离子与糖的羟基存在着复杂的相互作用. 相似文献
46.
耦合吸附吸收制冷系统设计及性能预测 总被引:1,自引:0,他引:1
耦合吸附吸收制冷系统(ADAB)具有运行压力接近常压的优点。本文针对以往的耦合系统设计中存在的问题, 设计了新型的耦合吸附吸收制冷系统。本文系统充分考虑了氨水溶液由吸收状态向发生状态切换时的显热损失问题,通过发生器和吸收器的分离设计,部分避免了由于切换时氨水溶液显热损失导致的系统制冷量减少甚至无冷量问题。本文对此新型系统的运行特性进行了理论研究,对其制冷性能进行了分析预测。分析结果表明该系统在蒸发温度5℃的空调工况下,系统性能系数GOP为0.18;若吸附制冷循环能够在40 min内完成,则新型系统的比吸附剂制冷量SGP为40.8 W/kg。 相似文献
47.
Photocatalytic hydrogen generation from water-splitting holds huge promise for resolving the current energy shortage and environmental issues.Nevertheless,it is still challenging so far to develop non-noble-metal photocatalysts which are efficient toward solar-powered hydrogen evolution reaction(HER).In this work,through an ultrasonic water-bath strategy combined with solvothermal and electrostatic assembly processes,we obtain homogeneous Cd1-xZnxS–Ni2P–MoS2 hybrid nano-spheres consisting of Cd1-xZnxS solid solutions decorated by Ni2P and 1 T/2 H MoS2 cocatalysts,which demonstrate excellent activity and stability for visible-light-responsive(λ>420 nm)H2 production.Specifically,the Cd1-xZnxS-Ni2P-MoS2 nano-spheres with 2 wt%Ni2P and 0.2 wt%MoS2(CZ0.7S–2 N–0.2 M)exhibit the optimal HER activity of 55.77 mmol·g-1·h-1,about 47 and 32 times more than that of CZ0.7S and Pt–CZ0.7S,respectively.The outstanding HER performance of Cd1-xZnxS–Ni2P–MoS2 can be ascribed to the presence of abundant HER active sites in Ni2 P nanoparticles and 1 T/2 H MoS2 nanosheets as well as the effective transfer and separation of charge carriers.Moreover,the coupling sequence of cocatalysts in Cd1-xZnxS–Ni2P–MoS2 is found to be critical in the regulation of charge transfer pathways and thus the resultant photocatalytic efficiency.The results displayed here could facilitate the engineering of high-performance photocatalysts employing multi-component cocatalysts for sustainable solar-to-fuel conversion. 相似文献
48.
Under single-collision beam-gas scattering conditions the reactions Ba+ C_2H, Br、n-C_3H_7Br、1, 2-C_2H_4Br_2、1,3-C_3H_6Br_2 have been studied using laser induced fluore-scence to detect the BaBr X~2∑~+ product. The vibrational distributions, the fractions of the available energy going into vibrational and rotational energy of the BaBr products have been calculated by means. of computer simulation. It has been found that the average vibrationel energies of the BaBr products can be described as a linear function of the mass factors for the reactions Ba+CH_3Br、C_2H_5Br、n-C_3H_7Br、1,3-C_3H_6Br, and that the potential energy surfaces for these reactions are similar. For the reactions Ba+CH_3Br、C_2H_5Br、n-C_3H_7Br, the vibrational increae, but for the reactions Ba+CH_2Br_2、1,2-C_2H_4Br_2、1,3-C_3H_6Br_2, the vibrational excitations of the BaBr products decrease greatly when the number of the carbons increase. 相似文献
49.
纳米级Mgo粉体的合成 总被引:20,自引:0,他引:20
采用化学沉淀法制备了薄片形氧化镁超微粉末,讨论了原始原料,浓度和温度对产物粒径的影响,通过XRD及TEM等实验手段对超微粉进行了表征。 相似文献
50.
Li-Wei Yuan Jing-Yi Zhu Yan-Qiu Wang Li Wang Ji-Ling Baiand Guo-Zhong He 《Chemical physics letters》2005,410(4-6):352-357
De-excited dynamics of p-chlorotoluene and p-dichlorobenzene have been investigated by the femtosecond pump–probe method in a supersonic molecular beam. The yields of the parent ion and daughter ion are examined as a function of the delay time between the pump and probe laser pulses. The lifetime constants of excited p-chlorotoluene and p-dichlorobenzene are determined. Possible de-excitation mechanisms are suggested that the initially excited S1 state is predissociative via the repulsive triplet state. The substituent effects of additional chlorine atom and methyl group are discussed. Moreover, for the first time, we observe a novel quantum beat oscillation in p-dichlorobenzene. 相似文献