沉淀聚合制备磺酸掺杂的聚苯胺

以二丁基萘磺酸（ＤＢＮＳＡ）或十二烷基苯磺酸（ＤＢＳＡ）为有机酸，水为主要反应介质的条件下进行沉淀聚合直接制备有机酸掺杂的聚苯胺（ＰＡｎ）．讨论了酸度、温度和氧化剂用量等反应条件对产物的影响．２Ｌ规模扩大实验的产率约为７５％～８０％，所得ＰＡｎ具有高电导率（３．０Ｓ·ｃｍ－１），并易溶于普通有机溶剂．其中ＰＡｎ－ＤＢＮＳＡ在各方面较具优势．

Effect of sintering temperature and holding time on structure and properties of Li_(1.5)Ga_(0.5)Ti_(1.5)(PO_4)_(3)electrolyte with fast ionic conductivity

Li_(1.5)Ga_(0.5)Ti_(1.5)PO_(4))_(3)(LGTP)is recognized as a promising solid electrolyte material for lithium ions.In this work,LGTP solid electrolyte materials were prepared under different process conditions to explore the effects of sintering temperature and holding time on relative density,phase composition,microstructure,bulk conductivity,and total conductivity.In the impedance test under frequency of 1-10^(6) Hz,the bulk conductivity of the samples increased with increasing sintering temperature,and the total conductivity first increased and then decreased.SEM results showed that the average grain size in the ceramics was controlled by the sintering temperature,which increased from(0.54±0.01)μm to(1.21±0.01)μm when the temperature changed from 750 to 950°C.The relative density of the ceramics increased and then decreased with increasing temperature as the porosity increased.The holding time had little effect on the grain size growth or sample density,but an extended holding time resulted in crack generation that served to reduce the conductivity of the solid electrolyte.

Data-Driven Viewpoint for Developing Next-Generation Mg-Ion Solid-State Electrolytes

Magnesium(Mg)is a promising alternative to lithium(Li)as an anode material in solid-state batteries due to its abundance and high theoretical volumetric capacity.However,the sluggish Mg-ion conduction in the lattice of solidstate electrolytes(SSEs)is one of the key challenges that hamper the development of Mg-ion solid-state batteries.Though various Mg-ion SSEs have been reported in recent years,key insights are hard to be derived from a single literature report.Besides,the structure-performance relationships of Mg-ion SSEs need to be further unraveled to provide a more precise design guideline for SSEs.In this viewpoint article,we analyze the structural characteristics of the Mg-based SSEs with high ionic conductivity reported in the last four decades based upon data mining-we provide big-data-derived insights into the challenges and opportunities in developing next-generation Mg-ion SSEs.

硅酸聚合粉金属重防腐水性和溶剂型涂料的研制

把无机硅酸粉与纳米导电态聚苯胺混合后的聚合粉分别与亲水和疏水硅烷聚合物进行有机杂化,再与水性环氧树脂、溶剂型环氧树脂和助剂进行交联,制成金属重防腐水性和溶剂型涂料产品。这些不含有任何金属颜填料的创新型产品,经过耐3000 h盐雾试验后,与国内和国际著名的金属重防腐涂料及粉末防腐涂料的耐盐雾实验结果进行对比,使硅酸聚合粉制造的水性和溶剂型重防腐涂料的优异防腐性能得到了验证。

不同类型的酸掺杂对聚苯胺结构和电导率的影响

合成了导电高分子本征态聚苯胺 (PANI)、盐酸掺杂聚苯胺 (HClPANI)和樟脑磺酸掺杂聚苯胺 (CSAPANI) .用傅立叶红外光谱 (FTIR)、紫外 -可见光谱 (UV Vis)对其掺杂前后的结构的变化进行了研究 ,分析了结构的变化对电导率的影响 。

Light-Induced Changes in a-Si∶H Films Studied by Transient Photoconductivity

Light induced changes in a-Si∶H films are investigated by transient photoconductivity.The transient photoconductivity decay data can neither be fit well by common power-law for transient photocurrent in amorphous semiconductors,nor by stretched exponential rule for transient decay from the steady state in photoconductivity.Instead,the data are fit fairly well with a sum of two exponential functions.The results show that the long time decay is governed by deep traps rather than band tail states,and two different traps locating separately at 0.52 and 0.59eV below E _c are responsible for the two exponential functions.They are designated as negatively charged dangling bond D - centers.The light-induced changes in photoconductivity are attributed mainly to the decrease in electron lifetime caused by the increase of recombination centers after light soaking.

Nonlinear dynamical response of high-voltage transmission lines based on cable dropping

In order to study the dynamic response of high-voltage transmission lines under mechanical failure, a finite element model of a domestic 500-kV high-voltage transmission line system is established. The initial equilibrium condition of the coupling system model is verified by nonlinear static analysis. The transient dynamic analysis method is proposed to analyze the variation law of dynamic response under cable or insulator rupture, and the dynamic response of structural elements next to the broken span is calculated. The results show that upper crossarm cable rupture has no effect on cable tension at adjacent suspension points, but it has a significant influence on tension in the insulator and the tower component of the upper crossarm next to the broken span. The peak tension in the conductor of the upper crossarm at the suspension point exceeds the design value under insulator rupture. Insulator rupture has no effect on the tower component of the upper crossarm, but it has a significant influence on insulator tension of the upper crossarm. Insulator rupture should be taken into account in the design of overhead transmission lines. The research results can provide a theoretical basis for the design of transmission lines.

Collisional Line Assignments and Hyperfine Structure Interpretation in Cs22^3△1g State

Accurately known energy level structure of the A＇∑u＋b3 IIu complex of states from a recent global de-perturbation of these states has enabled additional assignments of 140 perturbation facilitated infrared-infrared double resonance （PFIIDR） transitions to the 2^3△1g state from collisionally populated intermediate 1 ＋ A Eu levels. Together with the 221 previously observed 2^3△1g←A1∑u＋←X1∑g＋ Eu X Eg double resonance lines [J. Chem. Phys. 128, 204313 （2008）], molecular constants and the Rydberg-Klein-Rees potential energy curve of the 23△1g state have been recalculated （excluding 54 perturbed levels）. The centrifugal distortion constant has been determined and agrees well with the value calculated based on standard empirical formulas. The hyperfine structure of the 23△1g state, which has not resolved in our sub-Doppler excitation spectra of the 23△1g state, has been interpreted with a preliminary simulation.

An Improved On-Chip CMOS Astable Multivibrator

An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with duty-cycle equaling 50%. The latch-up effect has been prevented on the improved circuit. It is extremely important that all the excellent performances of the improved astable multivibrator have been achieved with a dynamic power consumption equaling its predecessor one. The advantage of the structure has been verified by SPICE simulation.

Structure of Reconstructed Cu（100） Surface Induced by Dissociative Adsorption of Gaseous Oxygen

The reconstructed structures of Cu（100） surface induced by O2 dissociative adsorption were investigated by low energy electron diffraction and scanning tunneling microscopy. At lower oxygen coverage, it was found that two reconstructed structures, i.e. c（2×2）-O and （√2×2√2）R45°-O are coexistent. The domain size of the c（2×2）-O structure decreased with the increasing of O2 exposure. The reconstructed structure at very small coverage was also investigated and a “zigzag” structure was observed at this stage. The “zigzag” structure was identified as boundaries of local c（2×2） domains. It was found that the strip region shows much stronger molecule-substrate interaction than that of oxygen covered regions, making it a proper template for patterned organic films. The sequence of the thermal stability was found as zigzag structure〉c（2×2）〉（√2×2√2）R45°-O.

先进功率半导体器件展示系统工程学的新方向

阐述了最近出现的几种器件的原理,诸如超级结型(Super Junction)MOSFET,IGBT和SiC(碳化硅)器件的发展趋势。所有这些器件都具有1000V范围的阻断能力,并适用于不同的领域。最新一代CoolMOS(低损耗MOS 场效应管)在额定脉冲电流容量下能兼有极高的通态导电率和超快的开关速度。其阻断电压能力可复盖由500～ 800V的范围。在许多应用场合,CoolMOS的杰出开关性能由于缺少能与动态特性相匹配的二极管而不能被利用。由于这个原因随之开发了一个完整的SiC二极管系列,以获得开关器件和超快二极管的理想配对。这种二极管的性能将在后面讨论。碳化硅开关器件表现出远胜于硅器件的性能。既有高阻断电压,又有低通态电阻率是SiC功率开关器件的最突出的特征。SiC器件最吸引系统设计人员之处在于其MOSFET和JFET能在阻断电压1800V下分别具有47mΩ·cm2和14.5mΩ·cm2的通态电阻率。为了用具体器件说明这些前景,我们将讨论通常为垂直型JFET结构的这类器件,其阻断电压高达1800 V,且通态电阻率为12mΩ·cm2。

Influence of polarized bias and porous silicon morphology on the electrical behavior of Au-porous silicon contacts

This paper reports the surface morphology and I-V curves of porous silicon （PS） samples and related devices. The observed fabrics on the PS surface were found to affect the electrical property of PS devices. When the devices were operated under different external bias （10 V or 3 V） for 10 min, their observed obvious differences in electrical properties may be due to the different control mechanisms in the A1/PS interface and PS matrix morphology.

An Extended Model for Coexistence of Superconductivity and Paramagnetism in High-T_c Superconductors

In the present work, the total magnetization in superconducting state is separated into critical state and paramagnetic components in terms of an H（x）-dependent magnetic flux density. Utilizing this model, we reproduce successfully M-H curves measured by Sandu et al. [Phys. Rev. B 74 （2006） 184511] and Sandu et al. [J. Supercond. Incorp. Novel Magn. 17 （2004） 701] for different forms of Jc.

Generating Squeezed States in Solid State Circuits

We propose a scheme for generating squeezed states in solid state circuits which consist a superconducting transmission line resonator （STLR）, a superconducting Cooper-pair box （CPB） and a nanoelectromechanical resonator （NMR）. The nonlinear interaction between the STLR and the CPB can be implemented by setting the external biased flux of the CPB at some certain points. The interaction Hamiltonian between the STLR and the NMR is derived by performing Fr ohlich transformation on tile total Hamiltonian of tile combined system. Just by adiabatically keeping the CPB at the ground state, we get the standard parametric down-conversion Hamiltonian, and the squeezed states of the STLR can be easily generated, which is similar to the three-wave mixing in quantum optics.

Electronic States of a Shallow Hydrogenic Donor Impurity in Different Shaped Semiconductor Quantum Wells

The shallow hydrogenic donor impurity states in square, V-shaped, and parabolic quantum wells are studied in the framework of effective-mass envelope-function theory using the plane wave basis. The first four impurity energy levels and binding energy of the ground state are more easily calculated than with the variation method. The calculation results indicate that impurity energy levels decrease with the increase of the well width and decrease quickly when the well width is small. The binding energy of the ground state increases until it reaches a maximum value, and then decreases as the well width increases. The results are meaningful and can be widely applied in the design of various optoelectronie devices.

Empirical decay relationship between ionic conductivity and porosity of garnet type inorganic solid-state electrolytes

Ionic conductivity is one of the crucial parameters for inorganic solid-state electrolytes.To explore the relationship between porosity and ionic conductivity,a series of Li_(6.4)Ga_(0.2)La_(3)Zr_(2)O_(12) garnet type solid-state electrolytes with different porosities were prepared via solid-state reaction.Based on the quantified data,an empirical decay relationship was summarized and discussed by means of mathematical model and dimensional analysis method.It suggests that open porosity causes ionic conductivity to decrease exponentially.The pre-exponential factor obeys the Arrhenius Law quite well with the activation energy of 0.23 eV,and the decay constant is averaged to be 2.62%.While the closed porosity causes ionic conductivity to decrease linearly.The slope and intercept of this linear pattern also obey the Arrhenius Law and the activation energies are 0.24 and 0.27 eV,respectively.Moreover,the total porosity is linearly dependent on the open porosity,and different sintering conditions will lead to different linear patterns with different slopes and intercepts.

Substitution Effects on MgB2 Superconductivity

With the help of supercell method, the first-principle calculations were performed for the study of doping crystal Mg1-xAlxB2 and Mg（B1-yCy）2. Analyzing the variations of the charge distribution and the partial densities of states, we found that the compounds with doping Al to MgB2 compound and/or replacing boron by carbon exhibit new covalent bond effects and unexpected electronic properties, related to superconductivity. The study of the density of states indicates that superconductivity decreases with the increase of Al fraction and carbon concentration. There exists a transition of superconductor to non-superconductor with the change of Al doping fraction. The substitution of boron by carbon results in the decrease of the transition temperature since the decrease of the electron concentration and the lattice constant. The theoretical predictions agree with experimental observations.

Measurement of Deep Energy Level in InP: Fe by the Method of OTCS

We have measured the deep energy level of the InP: Fe which is semi -insulator through the method of OTCS. The effect of light intensity on OTCS measurement is mainly discussed. There are electron trap of E_T =0.34 eV and hole trap of E_T = 1.13 eV in InP: Fe under the strong light and low temperature. The location of the OTCS peak of electron trap (E_T = 0.34 eV) moves towards the direction of high temperaturer, when the light intensity was increased, E_T is different under different light intensity. It is corrected in terms of theory that the stuff ratio of the deep energy level is affected by the light intensity. The experiments show that the error is decreased greatly with the correction.

Elastic stability of shallow pin-ended parabolic arches subjected to step loads

Buckling could be induced when shallow arches were subjected to vertical step loads. In-plane static and dynamic buckling of shallow pin-ended parabolic arches with a horizontal cable was investigated. Based on the equations of motion derived from Hamilton's principle, nonlinear equilibrium equations and static buckling equilibrium equations were deduced. Through the pseudo-static analysis, approximate solutions to the lower and upper dynamic buckling loads under step loads were obtained, for shallow parabolic arches. The results show that dynamic buckling and snap-through buckling are impossible when modified slenderness ratio λ<λc and λ>λs, where λc and λs denote critical slenderness ratios of bucking and snap-through buckling, respectively; effects of the stiffness of the horizontal cable on the dynamic buckling are significant; and the dynamic buckling loads under a equivalent central concentrated step load are lower than the loads under a distributed load appreciably.

Essence of Pseudogap and Oscillation in High-Temperature Cuprate Superconductor Junction of Pseudogap State

This paper gives methods to calculate the pairing temperature T＊, at which a pseudogap is opened, and the superconducting temperature Tc, at which superconductivity appears, in the high-Te cuprates, and demonstrates directly that at Tc 〈 T 〈 T＊ the pseudogap is the gap of Cooper pair without long-range phase coherence, and at T 〈 Tc there is long-range phase coherence between Cooper pairs. Based on the above clear physical picture on the pseudogap state and our mechanism for the ac Josephson effect, this paper proposes that there should he a novel oscillatory current in P-I-P junction, induced by a constant bias on the junction. Here, P represents the high-Tc curates in the pseudogap state, where Cooper pairs do not have long-range phase coherence, and I represents the thin insulating barrier. This paper conjectures that there is a possible high-temperature superconductivity in the heavily underdoped high-Tc cuprates.