聚(丙烯酰胺-丙烯酸)/聚(丙烯酰胺-二甲基二烯丙基氯化铵)聚电解质复合溶液动态光散射研究

通过动态光散射、粘度和透光率测定，研究了聚（丙烯酰胺 丙烯酸）［Ｐ（ＡＭ ＡＡ）］／聚（丙烯酰胺 二甲基二烯丙基氯化铵）［Ｐ（ＡＭ ＤＭＤＡＡＣ）］聚电解质复合溶液的结构和性能．结果表明，Ｐ（ＡＭ ＡＡ）与Ｐ（ＡＭ ＤＭＤＡＡＣ）复合比、溶液浓度和氯化钠用量影响溶液中复合物的构象和流体力学半径．Ｐ（ＡＭ ＡＡ）与Ｐ（ＡＭ ＤＭＤＡＡＣ）分子链间适度的库仑相互作用，可形成均相Ｐ（ＡＭ ＡＡ）／Ｐ（ＡＭ ＤＭＤＡＡＣ）聚电解质复合溶液，复合物具有较伸展的构象和较大的流体力学半径，因而溶液粘度较高．Ｐ（ＡＭ ＡＡ）与Ｐ（ＡＭ ＤＭＤＡＡＣ）分子链间过强的库仑相互作用或小分子电解质的屏蔽作用，可使复合物构象卷曲，结构紧缩，流体力学半径减小，甚至产生相分离，导致溶液粘度降低．     

乙烯－丙烯共聚物磺酸盐离聚物的研究Ⅲ 离聚物的性质

考察了乙烯－丙烯共聚物磺酸钠离聚物的动态力学性能、力学性质和热稳定性等随离子含量的变化，讨论这些性质与离聚物结构的关系．另外，以离聚物为分离膜，用渗透蒸发方法进行乙醇－水混合液的分离，初步探讨了膜离子浓度、离子种类、实验温度和混合液组成等因素对该膜分离特性的影响。     

Computer Simulation of Eley‐Rideal Reactions Over Rough Surface

The effect of surface roughness on an Eley‐Rideal reaction mechanism is studied. The rough surfaces are generated over a 2‐dimensional square lattice using the random deposition model. In an Eley‐Rideal reaction mechanism, a reacting particle approaches from the bulk and reacts with an active site upon collision with it. Three different rough surfaces are considered for the study. Multifractal scaling analysis is performed where the complex distribution of reaction probabilities is analyzed. Two cases of reactions are considered. 1) The reacting particle reacts at its first contact to the surface and 2) the reacting particle diffuses till it finds the lowest‐height position and reacts. The results obtained from the above two cases are compared. Significant differences between τ(q) and f(α) multifractal spectra for these two cases are found. The larger deviation from linearity in the τ(q) curves for the latter than the former gives wider f(α) spectra, indicating greater heterogeneity in the reaction probability distribution. Dynamic scaling theory is also applied on the Eley‐Rideal reaction mechanism over the surface with different surface roughnesses to obtain the two scaling parameters α_d and β_d. The values of α_d and β_d are found to be negative.     

基于标准CMOS工艺的UV/blue光电探测器

基于UMC 0.18μm CMOS工艺,提出一种适合紫外/蓝光探测的探测器,该器件由栅体互联的NMOS晶体管和横向/纵向光电二极管构成.其中,浅结的光电二极管由UMC工艺中Twell层(浅P阱)和Nwell层形成,以增强其对紫外/蓝光的吸收,栅体互联的NMOS晶体管可以放大光电流,提高探测器的灵敏度和动态范围.仿真结果表明,本文设计的紫外/蓝光探测器具有低的工作电压和暗电流,对300~550nm波长范围的光具有高的响应度和宽的动态范围.在弱光条件下(光强小于1μW/cm2),响应度优于105 A/W,随着光强增大,响应度逐渐降低,但总体仍超过103 A/W.     

Dynamic modelling and input-energy comparison for the elevator system

The elevator system driven by a permanent magnet synchronous motor (PMSM) is studied in this paper. The mathematical model of the elevator system includes the electrical and mechanical equations, and the dimensionless forms are derived for the purpose of practicable upward and downward movement. In this paper, the trapezoidal, cycloidal, five-degree (5-D) and seven-degree (7-D) polynomial and industry trajectories are designed and compared numerically in various motion and the absolute input energies. From numerical simulations, it is found that the trapezoidal trajectory consumes the minimum energy; the 7-D polynomial trajectory consumes the maximum one. The less end-point constraints are required, the less energy is consumed. Finally, the proposed sliding mode controller (SMC) is employed to demonstrate the robustness and well tracking control performance numerically.     

Conformational equilibrium and dynamic behavior of bis‐N‐triflyl substituted 3,8‐diazabicyclo[3.2.1]octane

Restricted rotation about the N–S partial double bonds in a bis‐N‐triflyl substituted 3,8‐diazabicyclo[3.2.1]octane derivative 1 has been frozen at low temperature (ΔG^≠ = 11.6 kcal mol^?1), and the existence of all four rotamers about the two N–S bonds, 3‐in,8‐in, 3‐in,8‐out, 3‐out,8‐in, and 3‐out,8‐out, respectively, proved experimentally by NMR spectroscopy and theoretically by DFT and MP2 calculations. Copyright © 2014 John Wiley & Sons, Ltd.     

Effect of bilayer repeats on magnetic properties of Au-buffered Co/Ni multilayers with perpendicular magnetic anisotropy

The effect of bilayer repeats (N) on the static and dynamic magnetic properties of Co/Ni multilayers was investigated. The effective perpendicular magnetic anisotropy constant of multilayers drops from $1.08\times {10}^6$ erg/cm³ to $0.78\times {10}^6$ erg/cm³ with N increasing from 5 to 11. For Co/Ni multilayers with $N\le 7$, sharp magnetization switching was observed. In contrast, Co/Ni multilayers with $N\ge 9$ have a long tail in the hysteresis loop. Ferromagnetic resonance measurements show that intrinsic Gilbert damping changes from 0.021 to 0.016 with increase in N and is inversely proportional to N. This study provides a deep understanding and effective control of magnetic properties of Co/Ni multilayers for spintronics devices.     

Thermodynamic studies of dynamic metal ligands with copper(II), cobalt(II), zinc(II) and nickel(II)

The self-assembly of unsymmetrical metal ligands from simpler components circumvents complex synthetic approaches. We show herein how a recently developed three-component assembly to create tripicolylamine-like ligands can be extended to the use of azides rather than pyridines. Substituent effects, metal dependence, and reversibility of the assembly are explored. Further, we show that the extent of assembly directly correlates with the differential binding of the templating metals between dipicolylamine-like and tripicolyamine-like ligands.