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91.
Binglin Lu 《Journal of statistical physics》1987,49(3-4):669-684
The coagulation equation with kernelK
ij
=A+B(i+j)+C
ij and arbitrary initial conditions is studied analytically and a simple expression for the solution is found. For monodisperse initial conditions, we recover the known size distribution expressed in terms of a degeneracy factorN
k, which is determined by a recursion relation. For polydisperse initial conditions, a similar solution form is found, which includes a degeneracy factorN
kl, also determined by a recursion relation. The physical meaning ofN
kl and the recursion relation is given. A method to get explicit expressions forN
k andN
kl is illustrated. Finally, the pre-gel solution is given explicitly and a general method to get the post-gel solution is proposed. 相似文献
92.
Rescaled mean spherical approximation (RMSA) has been used to calculate the structure factor for the aqueous suspension of
polystyrene macroions with the interaction potential taken according to Derjaguin and Landau (1941) and Verwey and Overbeek
(1948) (DLVO) model. The effects of charge over the macroion and size on the surface potential and therefore, the structure
factor have been studied. The breakdown of the DLVO potential with an excess charge over the macroion (⩾800e) has been reported.
The oscillation in the first peak height of structure factor versus wave vector curve with size has been correlated with the
Debye length. 相似文献
93.
因子分析-导数光谱法测定苯酚和间苯二酚混合物 总被引:3,自引:0,他引:3
本文测定了苯酚和间苯二酚混合体系的一阶导数光谱数据,用目标因子分析对这些导数数据进行处理,以探索因子分析在导数光谱中应用的可能性。在不加任何分离的情况下,成功地确定了苯酚和间苯二酚混合体系中的物种数、物种种类及含量。 相似文献
94.
95.
S.S. Joshi 《Applied Surface Science》2006,252(24):8539-8543
In the present work, for the first time, heterojunction has been fabricated using electrochemically deposited isotype p-selenium-p-polyaniline from a single solution bath. The structural characterization of selenium and polyaniline thin film was carried out using XRD technique. Polyaniline exhibited amorphous structure while selenium offered monoclinic (β) phase. The junction was formed by electrodepositing polyaniline over selenium film and heating at 423 K. The current density versus voltage (J-V) plot showed the formation of a junction with ideality factor of 1.16. From J-V characteristics at different temperatures, static resistance (Rs), dynamic resistance (Rd), and rectification ratio of diodes were determined. Heat treatment above 448 K caused junction breakdown. 相似文献
96.
akir Aydoan Mustafa Salam Abdulmecit Türüt 《Journal of Polymer Science.Polymer Physics》2006,44(11):1572-1579
The polypyrrole/p‐InP structure has been fabricated by the electrochemical polymerization of the organic polypyrrole onto the p‐InP substrate. The current–voltage (I–V), capacitance–voltage (C–V), and capacitance–frequency (C–f) characteristics of the PPy/p‐InP structure have been determined at room temperature. The structure showed nonideal I–V behavior with the ideality factor and the barrier height 1.48 and 0.69 eV respectively. C–f measurements of the structure have been carried out using the Schottky capacitance spectroscopy technique and it has been seen that there is a good agreement between the experimental and theoretical values. Also, it has been seen that capacitance almost show a plateau up to a certain value of frequency, after which, the capacitance decreases. The higher values of capacitance at low frequencies were attributed to the excess capacitance resulting from the interface states in equilibrium with the p‐InP that can follow the a.c. signal. The interface state density Nss and relaxation time τ of the structure were determined from C–f characteristics. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1572–1579, 2006 相似文献
97.
基于ANSYS 7.0/LS-DYNA程序,对3 m×3 m四边简支、厚度为0.025 m、中心开有0.3 m×0.3 m方孔的弹性板,在下三角爆炸载荷作用下的应力响应进行了分析;利用能量密度时间分布函数(TDFED)确定了动应力集中因子,重点讨论了时间步长和采样时间间隔对计算结果的影响。 相似文献
98.
采用实验法、数理统计法对江西省不同等级男子跳远运动员踏板准确性受环境因素影响进行研究.结果表明:塑胶跑道与煤渣跑道,顺风跑,逆风跑,阴天,大量观众,噪音对跳远踏板准确性都具有较明显的影响.跳远运动员踏板的准确性一般不受运动员等级水平的影响. 相似文献
99.
Both homogeneous and asymmetric polyethersulfone (PES) membranes were prepared by solvent casting. The sorption and permeation behavior of CO2, O2, and N2 using these two kinds of cast PES membranes and commercially available homogeneous PES film was investigated to extract the pressure dependence of gas permeability and the permselectivity for CO2 relative to N2, and to confirm the validity of the working assumption that a skin layer in an asymmetric membrane can be essentially replaced by a thick homogeneous dense membrane. The pressure dependence of the mean permeability coefficient to CO2 in homogeneous membranes obeys the dual-mode mobility model. The ideal separation factor for CO2 relative to N2 at an upstream pressure of 0.5 MPa attains ca. 40, while the permeability to CO2 is about 2.7 Barrer at the same upstream pressure. The same separation factor in asymmetric membranes amounts to 35. The diffusion behavior for the skin layer in an asymmetric membrane with a thin skin layer can be simulated approximately by that in a homogeneous dense membrane. © 1993 John Wiley & Sons, Inc. 相似文献
100.