Thermal unfolding of β‐lactoglobulin, α‐lactalbumin,and bovine serum albumin. A thermodynamic approach

Heat‐treatment is one of the most commonly used processes in food preparation technology. An understanding of the thermodynamics of protein stability and of conformational changes of proteins, acquired through the measurement of the denaturation temperature, is therefore of particular importance. This paper attempts to shed light on the interpretation of recent calorimetric data on the thennal denaturation of bovine β‐lactoglobulin, α‐lactalbumin, and bovine serum albumin by showing that thermodynamic parameters of heat‐induced unfolding, measured by differential scanning calonmetry, are closely related to the prevailing chemical conditions such as pH, concentration of ions, protein purity, and protein concentration.     

用于高速切削加工的磁力轴承主轴特性

介绍了用于高速切削加工的磁力轴承主轴的结构、刚性曲线及其耐磨损、低功耗、高精度、高速度等主要特性，并通过与传统的各类轴承主轴的比较，揭示出磁力轴承主轴的优良特性及其广阔的使用前景     

Weldability of thin sheet metals by small-scale resistance spot welding using high-frequency inverter and capacitor-discharge power supplies

An investigation has been conducted of the weldability of 0.2-mm-thick sheet aluminum, brass, and copper in small-scale resistance spot welding using a high-frequency inverter and a capacitor-discharge power supply. The results have been compared to those of previous investigations using a line-frequency alternating current power supply. The effects of electrode materials and process parameters on joint strength, nugget diameter, weld-metal expulsion and electrode-sheet sticking were studied. This work has also provided practical guidelines for selection of power supplies, process parameters (welding current/pulse energy, welding time/pulse width, electrode forces, etc.) and electrode materials for small-scale resistance spot welding of thin sheet aluminum, brass and copper.     

Al粉对含铝炸药爆轰性能的影响

为了研究A1粉对含铝炸药爆轰性能的影响,选择以TNT和RDX为基的含铝炸药进行了爆速、爆压和爆热的测量,通过计算得到了含铝炸药的爆轰能量转化率,分析了Al/O摩尔比对爆轰参数及爆轰能量转化率的影响规律.结果表明:随着Al/O摩尔比的增大,含铝炸药的爆压、爆速和爆轰能量转化率均降低,而爆热呈先增大后减小趋势,当Al/O摩尔比为1时,爆热值达到最大.     

Parameters estimation and detection of MIMO-LFM signals using MWHT

This article proposed an improved Wigner–Hough Transform (WHT) for multicarrier LFM signals of MIMO radars (MIMO-LFM). First, the signal model of the intercepted MIMO-LFM signals and the localisation of conventional WHT for this signal model are analysed. Therefore, we present the new WHT with multiple matching components, which is called as multicomponent WHT (MWHT). Then the detection and parameters estimation performance of MWHT are deduced, and analytical results indicate that MWHT is superior to conventional WHT for MIMO-LFM. In order to reduce the computation cost, a coarse estimation method is introduced. Finally, the numerical simulations demonstrate the validity of MWHT, as well as analytical results.     

共振隧穿器件概述——共振隧穿器件讲座(1)

通过对共振隧穿器件的特点、分类、工作原理、电流成分、器件参数等的介绍,为初学人员或非专业爱好人员提供一个对共振隧穿器件全面的、概括性的认识。     

Current-voltage characteristics of p-Si/carbon junctions fabricated by pulsed laser deposition

Amorphous carbon/p-Si junctions were fabricated at different temperatures using KrF excimer laser (λ = 248 nm, pulsed duration 20 ns). The current-voltage measurements of the devices showed diode characteristics. The value of various junction parameters such as ideality factor, barrier height, and series resistance were determined from forward bias I-V characteristics, Cheung method, and Norde’s function. There was a good agreement between the diodes parameters obtained from these methods. The ideality factor of ∼1.12 and barrier height of ∼0.37 eV were estimated using current-voltage characteristics for films grown at room temperature.     

悬浮铝粉尘爆轰波参数

用两相流模型对爆轰波管中的悬浮铝粉尘的爆轰波进行了研究。数值模拟了管径为15.2cm的圆管中平均粒子直径为3.4μm、单位质量表面积为3m2·g-1的铝粉尘中爆轰波的传播和发展,得到了不同浓度时悬浮铝粉尘爆轰波参数,并得到了爆轰极限的下限为当量比=0.25。数值计算给出管径趋于无穷大时不同铝粉尘浓度时爆轰波的参数,得到悬浮铝粉尘爆轰极限的下限为当量比=0.16。数值模拟了当量比为=1、管径不同时爆轰波速度的变化,并得到产生爆轰的临界管径。     

埋栅结构双极型静电感应晶体管动态特性的改善

双极型静电感应晶体管(BSIT)的失效经常出现在阻断态与导通态之间的瞬态过渡过程。因此,研究BSIT的开关动态过程的物理机理对于设计和制造高性能器件有着重要意义。本文深入研究了埋栅结构电力BSIT瞬态过程的动态特性,讨论了材料、几何结构与工艺参数对BSIT动态性能的影响。提出了一系列改善BSIT动态特性的工艺措施。     

旋转波片法测量电光调Q射频波导CO2激光器的内部参数

提出了一种测量电光调 Q射频波导 CO2 激光器内部参数的新方法 ,采用此方法可测量出激光器的小信号增益系数、内部损耗、饱和光强等内部参数 ,并可推广应用到其他种类激光器内部参数的测量。