差示扫描量热法(DSC)鉴别细菌的研究

本研究初步建立了用差示扫描量热法鉴别细菌的技术。用0℃～550℃的DSC指纹图,对8株(5类)细菌进行了鉴别,获得了满意的效果,为微生物分析提供了一种新的、快速的、自动的手段。     

四缩水甘油基-4,4,-二氨基二苯甲烷/1,4-双(4-氨基苯氧基)苯环氧树脂体系固化反应的动力学模型

为了描述四缩水甘油基-4,4,-二氨基二苯甲烷/1,4-双(4-氨基苯氧基)苯(TGDDM/144BAPB)树脂体系的固化行为,由反应机理提出了一个动力学模型:dα/dt=Ka(1-α)2 Kbαm(1-α)n,由等温差示扫描量热法(DSC)求出参数Ka、Kb、m、n的值,结果表明:由模型算出的反应速率和由DSC实验得出的结果吻合得很好。     

Ce-Al-Cu非晶合金制备及非晶形成能力

为研究Ce-Al-Cu非晶合金的制备及非晶形成能力（GFA）,采用熔体旋淬法制备了Ce70AlxCu30-x（x=5,10,13）、Ce80-xAlxCu20（x=10,15,20）和Ce90-xAl10Cux（x=15,20,25）非晶合金薄带。用X-射线衍射法（XRD）进行物相表征,用差示扫描量热法（DSC）测量样品在加热过程中的相变规律,对合金的非晶形成能力与非晶形成能力的参数（Tg、Tx、Tm、Tl、Trg、η）进行分析。结果表明,Ce含量的适当增加和Al含量的适当降低有利于降低Trg,有利于非晶形成;Cu含量的改变对非晶的形成产生极大的影响,但当Cu的原子分数为20%时,Tg最低,对Tx和Tl的影响亦不大;Ce70Al10Cu20相对此合金的其他成分点具有更好的非晶形成能力,且快淬速度为15 m/s时非晶形成能力最好。     

差示热重测量低挥发煤的反应性

改用均匀粒度粒子、标准燃烧曲线（型谱）试验测量一组低挥发澳大利亚煤的反应性．找出燃尽期间粒子收缩性与挥发分的函数关系，燃尽粒子表面积变化，发现５—８５％燃尽范围内活化能稳定。Ⅱ态燃烧的活化能随挥发分增加而减少，所测反应性值与其他报导高温载气燃烧同一煤的反应性值一致，但没介绍９００℃以上差示热重（ＤＴＧ）动力学值外推。     

聚醚砜-聚醚醚酮机械共混物相容性和热性能的研究

本文以DSC法研究了机械法制备的PES-PEEK共混物的相容性和热性能.实验表明,热处理后PES-PEEK机械共混物具有一定的相容性,PES可以有效降低PEEK的结晶性;共混物低温熔融温度(T_L)、熔融温度(T_m)、热焓及结晶度与热处理温度有关.     

共混改善聚乙烯空间电荷分布的研究

在高场强下用电声脉冲法（PEA）测量了低密度聚乙烯和线性低密度聚乙烯共混物中的空间电荷分布,用差示扫描量热法（DSC）研究了共混物的形态。实验结果表明：与纯低密度聚乙烯相比,共混可以降低空间电荷。文章最后分析了共混后对空间电荷影响的机理。     

差示扫描量热法测定热电池材料中的微量水分

介绍了利用差示扫描量热法 (DSC)测定电池材料中微量水分的新方法 ,它是基于在适当条件下 ,测定蒸馏水及材料中水分的蒸发热 ,从而间接测定材料的含水量。用该方法测出的 4种材料的含水量 ,其标准偏差范围为 0 .0 2 %～0 .0 8% ,实验证明 ,材料的DSC曲线上的热峰是由水蒸发引起。该方法与常规的卡尔费休法和质量法等相比 ,具有准确、快速和样品量少等特点 ,更加适用于易吸潮材料中水分的测定     

磁化水熔化热焓的研究

回顾了近年来对某些介质磁化效应的研究概况。着重报导了作者利用高精度差示扫描量热分析仪对磁化水熔化热熔的测量结果。实验结果很难说明磁化能给水的熔化热焓带来令人信服的变化。     

用DSC研究环氧树脂的固化反应

本文用动态与等温DSC研究了环氧树脂—甲苯钠迪克酸酐—苯甲酸铅的固化反应动力学,方法较简便。动态法测得该反应为二级反应,活化能E为59.9kJ/mol,频率因子A为1.3×10~6;等温法测得E为62.4kJ/mol,A为1.2×10~5。     

有机硅无溶剂浸渍漆的固化动力学研究

采用示差扫描量热法(DSC)对有机硅无溶剂浸渍漆分别在5℃/min、10℃/min、15℃/min、20℃/min4个不同升温速率下的固化过程进行动态扫描。通过T~β外推法确定了该浸渍漆的固化工艺参数,根据Kissinger-Ozawa方法求得该漆固化反应的活化能为16.684 kJ/mol,碰撞因子为5.951×103。通过Crane方程求得固化反应级数为1.127。     

基于减法聚类的TOA/AOA定位方法研究

针对在无线传感网中现有定位技术定位精度不高的问题,提出一种基于减法聚类的定位方法以获取更好的定位性能和更高的定位精度.首先由多个已知传感器节点测量来自未知节点的电波到达时间和电波达到角,通过分组处理,然后对每组数据进行加权最小二乘估计,依据多次测量和估计,最后采用减法聚类处理来抑制误差导致的位置模糊性来实现对未知节点的精确定位.计算机性能仿真结果表明所提出的定位方法能有效地抑制测量误差,具有较小的定位误差,并进一步提高了定位精度.     

用自适应模糊推理系统预测电力短期负荷

为寻求有效的电力系统负荷预测方法以提高预测结果的准确度,提出了基于Takagi-Sugeno(T-S)模型的自适应神经模糊推理系统(ANFIS)。该系统采用减法聚类初始化模糊推理,把神经网络学习机制引入到逻辑推理中,并用混合学习算法调整前件参数和结论参数,自动产生模糊规则。考虑气象、日期类型等因素后将学习样本分为3组进行训练和检测。该方法对于受天气影响较明显的电网,能有效防止不合理预测结果的出现。对于武汉地区实际负荷的预测结果的分析表明该方法有较高的预测准确度,取得了令人满意的结果。     

基于减法聚类及自适应模糊神经网络的短期电价预测

提出了基于Takagi-Sugeno模型的自适应模糊神经网络的短期电价预测方法。首先采用减法聚类方法确定自适应模糊神经网络的结构,然后利用混合学习算法训练该网络的前件参数和结论参数,最后将影响未来日电价的相关因素输入到训练好的自适应模糊神经网络中进行电价预测。以美国加州电力市场公布的1999年负荷与电价数据进行模型训练和预测,结果表明采用该方法所建立的预测模型具有较高的预测精度。     

An adaptive limited wide area differential protection for power grid with microsources

The operation mode of power grids with intermittent distributed generations (DGs) changes frequently due to the bidirectional power flow. In comparison with the conventional grids, the protection relays in power grids with micro-sources are more difficult to set. To tackle this problem, this paper proposes an extended bus differential protection (EBDP) strategy based on the limited wide area (LWA). In this method, the micro-grids are divided into several protection areas at the core of the bus. The whole protection areas are protected by the wide area current differential relays, which are also configured to protect each component in this protection area. Moreover, the protection areas can be changed adaptively according to the power flow direction. Finally, a micro-grid model with multiple DGs is developed using the PSCAD/EMTDC platform. The simulation results indicate that the proposed adaptive limited wide area differential protection (LWADP) has better performance than the traditional relaying protection in detecting the faulty area in micro-grids and isolating the fault, and can be widely utilized in larger micro-grids.     

An adaptive limited wide area differential protection for power grid with microsources

The operation mode of power grids with intermittent distributed generations (DGs) changes frequently due to the bidirectional power flow. In comparison with the conventional grids, the protection relays in power grids with micro-sources are more difficult to set. To tackle this problem, this paper proposes an extended bus differential protection (EBDP) strategy based on the limited wide area (LWA). In this method, the micro-grids are divided into several protection areas at the core of the bus. The whole protection areas are protected by the wide area current differential relays, which are also configured to protect each component in this protection area. Moreover, the protection areas can be changed adaptively according to the power flow direction. Finally, a micro-grid model with multiple DGs is developed using the PSCAD/EMTDC platform. The simulation results indicate that the proposed adaptive limited wide area differential protection (LWADP) has better performance than the traditional relaying protection in detecting the faulty area in micro-grids and isolating the fault, and can be widely utilized in larger micro-grids.     

On stochastic modelling of linear circuits

In this paper, the deterministic modelling of linear circuits is replaced by stochastic modelling by including variance in the parameters (resistance, inductance and capacitance). Our method is based on results from the theory of stochastic differential equations. This method is general in the following sense. Any electrical circuit that consists of resistances, inductances and capacitances can be modelled by ordinary differential equations, in which the parameters of the differential operators are the functions of circuit elements. The deterministic ordinary differential equation can be converted into a stochastic differential equation by adding noise to the input potential source and to the circuit elements. The noise added in the potential source is assumed to be a white noise and that added in the parameters is assumed to be a correlated process because these parameters change very slowly with time and hence must be modelled as a correlated process. In this paper, we model a series RLC circuit by using the proposed method. The stochastic differential equation that describes the concentration of charge in the capacitor of a series RLC circuit is solved. Numerical simulations in MATLAB are obtained using the Euler–Maruyama method. Copyright © 2008 John Wiley & Sons, Ltd.     

热分析方法在金属陶瓷材料研究中的应用

介绍了热分析方法（包括差热分析法和热重分析法）的原理，并结合应用到金属陶瓷的性能测试与分析中，对新产品的性能研究提供了可靠的，有价值的分析结论。     

电网典型“死区”故障保护动作分析

"死区"故障故障点较难判断,对电力调度员来说是故障处理的难点,如不快速切除该区域内的故障,将严重威胁电力系统的安全稳定运行。文中简要分析了电网中几种常见的"死区"故障现象,提出了"死区"故障的处理方法和预防措施,并举例说明。     

变电站自动化系统遥信去抖方法分析

在辨别电网故障时各类事件发生的先后顺序中,SOE记录具有重要意义。该文对目前采用的遥信去抖方法进行分析,指出不同方法的特点。构建测试系统环境,在不同遥信去抖方法下,对SOE结果进行对比统计和分析。最后建议能够统一遥信去抖设计方法,保证SOE记录的精确性。     

信阳和驻马店地区电气化铁路谐波引起220kV高频保护动作的分析

本文根据现场实测数据，对１９９３年２月１２日河南省信阳和驻马店地区２２０ｋＶ计驻线高频保护动作引起大面积停电事故的原因作了深入的分析，得出了造成这次严重事故的原因是由于三个电气化铁路牵引站谐波电流严重超标的结论。