灰介电膜传热研究

用Boltzmann传输方程建立灰介电薄膜声子辐射传热方程，提出灰体介电薄膜的当量导热系数的概念，指出Fourier定律只适用于声学极厚区域，给出了用Fourier定律进行热流密度计算的误差。     

日本离子气相沉积研究的进展

日本日新电子公司用离子注入和真空沉积(IVD)方法在衬底和镀金属的陶瓷表面上生长氮化铝薄膜。这种具有一定电气及介电性质的氮化铝薄膜与烧结的氮化铝相似,其透明度比烧结氮化铝提高约     

石墨烯/聚酰亚胺介电复合材料的制备与性能

采用密闭氧化法制备氧化石墨,经过超声分散剥离得到氧化石墨烯(graphene oxide,GO),然后以聚乙烯吡咯烷酮为保护剂、维生素C(Vc)为还原剂,在N,N-二甲基甲酰胺溶液中还原氧化石墨烯,得到还原状态的石墨烯(reduced graphene oxide,rGO),最后采用原位复合、流涎成膜方法制备石墨烯/聚酰亚胺(rGO/PI)复合薄膜。利用傅里叶变换红外光谱仪(Fourier transform infrared spectroscopy,FTIR)、扫描电镜(SEM)、透射电镜(TEM)、X射线光电子能谱仪(X-ray photoelectron spectrograph,XPS)、热重分析/差式扫描量热分析(TGA/DSC)等多种表征方法对rGO和rGO/PI复合薄膜的形貌、结构和热稳定性进行分析,用宽频介电谱仪测试复合薄膜的介电性能。结果表明,rGO是一种高效的导电填料,极少的添加量即可显著提高PI的介电常数,且对PI的其它性能影响较小。rGO/PI复合薄膜的介电常数随rGO填料含量的变化规律符合逾渗阈值模型,逾渗阈值f0为0.461%,临界指数q为0.523。当rGO含量(质量分数)为0.7%时,薄膜的介电常数为35.1,是纯PI的8.4倍。     

非致冷红外焦平面阵列用铁电薄膜

在简要阐述红外成像发展现状基础上，系统介绍了铁电薄膜的性质、制备及在非致冷红外热成像系统应用中的一些热点问题。重点介绍当前有重大技术突破的介质测辐射热式焦平面探测器，比较了热释电模式、介电模式的优缺点及发展前景。由于介质测辐射热式信号获得方式较热释电式有较高的比探测率、响应率、成象精度和质量及较轻的体积和重量，可以预测在不断提高探测用铁电薄膜介电温度系数、损耗及大面积均匀性，不断改进其读出电路的基础上，将成为今后铁电非致冷红外热成像发展的主流。     

稀土氧化物改性的SrTiO_3陶瓷的介电性质

本文主要报道稀土氧化物改性SrTiO_3陶瓷的介电性质。用稀土氧化物掺杂改性SrTiO_3陶瓷,可以提高其介电常数和降低介质损耗,对其介电温度特性和介电频率特性也有明显的改善。     

新方法

Charles Evans正在研究一种对绝缘材料进行微量分析的技术。他们正在研究半导体器件和光学元件的绝缘薄膜、电光学元件和地质物料的化学微量分析,并研制了一种用于绝缘薄膜沉积过程控制的化学分析仪器。 定量微量分析技术第一次有可能从理论和实践两方面来深入理解介电材料的物理性质与其化学成分之间的关系。     

氧化铝膜理论(百问百答)

30.为什么硫酸溶液交流氧化处理法不能普及? 福岛敏郎博士就这个问题论述如下。“用交流法进行氧化处理难以形成10μ以上厚度的薄膜。并且,由于薄膜硬度低,现在还几乎不能用于工业生产。战后不久,将家庭用品用交流电介后,再用茶色浸出液进行染色。交流电介的特点,据说可以产生厚度7～8μ的软质可挠性薄膜。例如,在厚度0.05mm的铝箔     

保护气氛下电渣重熔过程中界面脱硫传质动力学

电渣重熔过程中渣金反应温度高,接触面积大,具有良好的脱硫传质条件.然而,渣金界面处存在着传质边界层,边界层的厚度会影响界面脱硫传质速率,这对研究界面脱硫传质具有重要的意义.本文基于菲克第二定律、渗透理论和薄膜理论,建立保护气氛条件下电渣重熔过程渣-金界面脱硫传质方程,研究温度对渣-金间脱硫传质速率的影响规律.研究结果表明:随着温度的升高,渣-金界面处硫的浓度减小,界面脱硫传质速率增大;渣-金界面硫扩散的传质边界层厚度不随温度发生变化.     

Y_2O_3改性的SrTiO_3陶瓷的介电性质

SrTiO_3系陶瓷是一种具有多功能特性的介质材料,用Y_2O_3改性SrTiO_3陶瓷,可以提高其介电常数和降低介质损耗,对其介电温度特性和介电频率特性也有明显的改善,本文主要报告Y_2O_3对SrTiO_3陶瓷介电性质的影响。     

上海理工大学电功能材料研究所

上海理工大学电功能材料研究所以新型导电材料及制备技术、功能薄膜材料和生物医用钛合金等高性能材料的设计、加工技术作为主要研究方向,重点开发大规模集成电路用引线框架材料及加工技术、高速列车接触网导线材料、高压真空开关触头材料、弥散强化铜合金、铜铝复介导电材料等。在高强度铜合金的强化机理,高强度高导电制合金的导电机理、合金化等方面都有较深入的研究。     

Sprague's Law: A profoundly simple strategy for counseling and self-help.

Hall T. Sprague (1973, 1977) developed S = R/E, in which satisfaction (S) results from the magnitude of the difference between reality (R) and expectation (E). He called this Sprague's law. Although a simple equation, Sprague's law has been used in counseling and supervision to boil down complex psychological issues and problems in living to 3 simple variables and their interactions. The principles underlying Sprague's law are briefly compared with psychological principles across several psychotherapy theories. The application of the equation is clarified. A variety of clinical applications and examples are presented. Finally, it is suggested that Sprague's law can be given away to make psychology a household word. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Practice and retention: A unifying analysis.

What is the strength of a memory trace that has received various practices at times tj in the past? The strength accumulation equation proposes the following: strength?=?Σtj–d, where the summation is over the practices of the trace. This equation predicts both the power law of practice and the power law of retention. This article reports the fits of the predictions of this equation to 5 experiments. Across these experiments, participants received as many as 240 trials of practice distributed over intervals as long as 400 days. The experiments also varied whether participants were just practicing retrieving an item or practicing applying a relatively complex rule. A model based on this equation successfully fit all the data when it was assumed that the passage of psychological time slowed after the experimental session. The strength accumulation equation was compared with other conceptions of the retention function and the relationship of the retention function to the practice function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Explicit Power Formula for the Darcy–Weisbach Pipe Flow Equation: Application in Optimal Pipeline Design

Although the Darcy–Weisbach equation combined with the Colebrook–White semitheoretical formula for calculating the friction coefficient is a highly accurate generalized pipe-water flow resistance equation, most users prefer the use of simple, explicit power law form formulas. Because of their simplicity (despite their limitations) the purely empirical power formulas of Hazen–Williams and Manning remain the most popular pipe flow resistance equations used in routine hydraulic engineering applications. In this paper, a new simple power law form formula is derived to approximate the generalized Darcy–Weisbach combined with the Colebrook–White equation. The two main pipe flow parameters, such as the discharge (or velocity) and the diameter, appeared explicitly in the proposed formula. The suggested power-form formula compared with the Darcy–Weisbach and Coolbrook–White equation yields a maximum relative error of about ±4.5%. The power-form suggested formula is dimensionally homogeneous and its accuracy is sufficient for practical engineering applications. A correction factor is introduced for the variation of kinematic viscosity with temperature. The usefulness of the formula is demonstrated in an application concerning the optimal design of a delivery pipeline with pumping. The power form of the friction formula facilitates the formulation of the problem leading to the derivation of a simple equation from which the economic diameter is explicitly calculated.     

Investigation of three-layer rectangular panel bending by variation method

The task of transverse bending of a rectangular three-layer panel with the lightweight filler is considered. The differential equation system of transverse bending of the panel is generated within the scope of Lagrange variational principle. An explicit solution of the differential equation system in double trigonometric Fourier series is obtained. It is shown that the maximum deflection of the three-layer panel can be compared with the three-layer beam deflection, with a multiple panel width excess over its length.     

球团添加菱镁石熔剂对焙烧工艺制度的影响

 为研究球团添加菱镁石熔剂对焙烧工艺制度的影响,在实验室条件下,将菱镁石熔剂添加到普通酸性球团中,利用傅立叶导热微分方程推导了球体不稳定导热微分方程,采用有限差分求解方法解析了菱镁石熔剂对球团传热过程的影响。分析结果表明：在相同焙烧条件下,普通酸性球团完成焙烧的时间为8.35 min,添加菱镁石熔剂的球团为9.13 min。建议在生产含氧化镁的酸性球团时,应适当提高预热段温度使熔剂中碳酸盐充分分解或适当延长焙烧时间,以实现球团的合理焙烧。     

Dilatothermy - a new quantitative research method for allotropic transformation

The authors have developed a mathematical heat treatment model which allows to take into account the exothermal effect of allotropic transformation and to predict the microstructure of heated products. In this model, the cooling law of the product is calculated by a numerical integration of the “Fourier” equation taking into account the internal heat production due to the allotropie transformation. The process of this transformation has to be known as kinetics equations. To reach this aim, the authors have developed a new method of studying the allotropie transformation and have it applied to different recrystallised carbon steels. The method consists of two steps: experimental and numerical. From the experimental point of view, a new technique, dilatothermy, has been developed. It consists of realising simultaneously a thermal analysis and a dilatometrie one on the same specimen and of benefitting from the advantages of both methods. From the numerical point of view, the results of dilatothermy tests are treated in order to find a complete mathematical model of transformation comprising, for each microstructure, and equation describing transformation kinetics, the value of transformation heat and the mean transformation temperature of each constituent. The validity of the heat treatment model has been checked by both computation and laboratory tests. Some application cases have been considered. It is shown that the models are applicable to all types of thermal treatment carried out industrially. They allow the calculation of the steel temperature, the amount of each microstructural constituent and the temperature range in which they were formed.     

Turbulence Measurement in Nonuniform Open-Channel Flow Using Acoustic Doppler Velocimeter (ADV)

Measurements of the mean and turbulence characteristics in nonuniform open-channel flows were carried out using a 3D acoustic Doppler velocimeter. Both accelerating and decelerating flows were investigated. Analyses based on the Reynolds equation and the continuity equation of 2D open-channel flow show that a flow will be in equilibrium if the pressure-gradient parameter β is a constant at different sections along the flow direction. The experimental data show that all the flows investigated are in equilibrium. The effect of the flow nonuniformity on the mean velocity and turbulence profiles was also examined. The study shows that (1) the log law is still valid for both accelerating and decelerating flows in the inner region. The Coles law can be used for the entire region, but the wake-strength parameter Π depends on the β-value; and (2) the turbulence intensities and the Reynolds stress decrease in accelerating flow and increase in decelerating flow, when compared with those in uniform flow. Finally, using the Reynolds equation and the continuity equation of 2D open-channel flow, the theoretical expressions for the distribution of vertical velocity and the Reynolds stress have been developed. The measured vertical velocity and the Reynolds stress profile compare well with the derived expressions.     

广义二阶流体的脉冲泊肃叶流动分析

讨论了广义二阶流体的脉冲泊肃叶流动,引入黎曼-刘维尔分数阶微分建立本构方程,结合不可压缩流体时间分数阶动量方程,得到控制方程.利用傅里叶正弦变换和分数阶拉普拉斯变换,获得流体速度解析解.利用Stehfest算法对结果进行数值模拟,通过图像讨论了分数阶参数以及延迟时间对流动的影响.结果表明速度过冲现象主要取决于动量方程的时间分数阶参数.      

A law of comparative judgment.

(This reprinted article originally appeared in Psychological Review, 1927, Vol 34, 273–286. The following is a modified version of the original abstract which appeared in PA, Vol 2:527.) Presents a new psychological law, the law of comparative judgment, along with some of its special applications in the measurement of psychological values. This law is applicable not only to the comparison of physical stimulus intensities but also to qualitative judgments, such as those of excellence of specimens in an educational scale. The law is basic for work on Weber's and Fechner's laws, applies to the judgments of a single observer who compares a series of stimuli by the method of paired comparisons when no "equal" judgments are allowed, and is a rational equation for the method of constant stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)