电阻分压器测量高压单脉冲方法的改进

根据实验结果，对分压器测量极窄的高压单脉冲方法进行分析后，认为此方法的缺陷在于忽视了分布电容的影响，通过引入补偿电容改进了分压器，由改进后的分压器模型的时域解，得出了改进测量方法的方案。     

冲击高压分压器高压臂用卡玛丝温度系数影响因素的研究

用于冲击高压分压器高压臂的卡玛丝,需将其均匀密绕于绝缘骨架上,然而,骨架的引入会给卡玛丝的温度系数带来影响。理论和实验证明骨架的热膨胀系数及其几何形状对卡玛丝产生的弯曲应变是改变卡玛丝温度系数的主要影响因素:当骨架的热膨胀系数大于材料本身的热膨胀系数时,温度系数的测量结果会大于电阻丝本身真实的温度系数;弯曲应变会引起K状态结构的破坏,使得电阻值减小。     

正弦波电压差分测量与多周期策略——阶梯波研究之三

将片段采样概念应用于正弦波电压的差分测量,把多周期策略施加于被测正弦波的频率扩展,通过实验演示上述测量的具体过程,验证方法的可行性。分析了阶梯波差分测量的特点。为适应这个特点,提出了限幅片段采样的概念及相应的方法。由此提出将交流量子电压基准的准确度提高一个数量级至10^-8水平的建议,叙述了它的原理及具体的方法,指出了所需要的条件。     

Impulse Modeling of the Rayleigh Wave Propagation Generated by a Spherical Focused Transducer

In order to characterize materials locally by means of the Rayleight wave analysis, a new modeling of acoustic microscopy in the case of an impulse excitation is presented. The usualV(z) representation established for a given frequency component, is extended to the case of a broadband excitation of the transducer. Therefore, the time-dependant acoustic response of the material,s(z,t), is mainly composed of two echoes: the specular and the Rayleigh contributions which are resolved in time. In the first part, we demonstrate that the acoustic response can be represented by the time convolution product between the acoustic signal detected at the focus on an ideal reflector, and a function depending onz andt variables. This last function is connected to the tranducer emission profile, which includes the diffraction effects, and the reflectance of the material. In the second part, the modeling is discussed with regard to experimental data on several materials and takes into account the attenuation phenomena. Experimental results and computations are shown to be in a good agreement.     

基于约瑟夫森量子电压的交流功率测量系统及方法研究

基于约瑟夫森量子电压标准设计了交流功率差分测量系统。通过分析差分采样系统的误差分布及误差传递函数,提出换向差分测量方法,减小了差分采样系统的增益误差,提高了电压幅值测量准确度;通过分析衰减系数η,证明了采用换向差分测量较容易实现10-7量级电压幅值测量。通过评估差分采样系统零相位,结果证明了差分采样系统具有较好的相位测量稳定性。分析了交流功率差分测量系统的不确定度分量,评估了功率因数为1.0,0.5 L和0.5 C时的功率测量不确定度,通过与国家交流功率基准装置进行实验比对,证明了基于约瑟夫森量子电压交流功率测量系统不确定度评估的合理性。     

Rechargeable Lithium Metal Batteries with an In-Built Solid-State Polymer Electrolyte and a High Voltage/Loading Ni-Rich Layered Cathode

Solid-state batteries enabled by solid-state polymer electrolytes (SPEs) are under active consideration for their promise as cost-effective platforms that simultaneously support high-energy and safe electrochemical energy storage. The limited oxidative stability and poor interfacial charge transport in conventional polymer electrolytes are well known, but difficult challenges must be addressed if high-voltage intercalating cathodes are to be used in such batteries. Here, ether-based electrolytes are in situ polymerized by a ring-opening reaction in the presence of aluminum fluoride (AlF₃) to create SPEs inside LiNi_0.6Co_0.2 Mn_0.2O₂ (NCM) || Li batteries that are able to overcome both challenges. AlF₃ plays a dual role as a Lewis acid catalyst and for the building of fluoridized cathode–electrolyte interphases, protecting both the electrolyte and aluminum current collector from degradation reactions. The solid-state NCM || Li metal batteries exhibit enhanced specific capacity of 153 mAh g⁻¹ under high areal capacity of 3.0 mAh cm⁻². This work offers an important pathway toward solid-state polymer electrolytes for high-voltage solid-state batteries.     

工业X射线光机管电压测量的研究

用非介入管电压测量仪测量了工业X射线光机标称管电压在70～120 kV的管电压,并与介入式测量方法的测量结果傲了比较;在用非介入式测量管电压时比较了不同附加过滤对测量结果的影响.结果显示,附加过滤的厚度会影响非介入式管电压测量结果的准确性,在实验条件下最大的标准偏差能达到2.5％,根据附加过滤对非介入式测量结果进行修正后最大偏差为0.4％.     

双面光伏组件的功率测试

双面光伏组件由于正反两面均能发电而受到关注,如何测试其功率是当下研究的热点。对目前行业内最新的3项标准草案和1项测试方案进行了介绍和比较,并对其测试方法提出了参考建议。通过试验发现:在不同标准的指导下,同一块组件功率的测试结果差异较大,双面光伏组件的功率测试需要统一的方案。     

脉冲电压信号测量系统

随着电子技术的发展,半导体开关元件的切换频率不断提高。为了检测开关元件在快速切换开关时产生的脉冲电压信号,本文讨论了窄脉冲信号检测的原理和方法,设计并实现了脉冲测量电路。该电路分别采用高速ADC和DDR2存储器进行波形采集和存储,并在FPGA中设计检测电路,通过信号同步触发的形式实现窄脉冲信号的实时检测。实验表明:系统能够有效捕获到脉宽为100纳秒级的信号,且具有较高的幅度精度以及良好的实时性。同时,预触发长度可以通过编程实现。     

切向流条件下穿孔板声学性能脉冲法测量技术

采用脉冲测量法,通过在管道内生成波形良好的可控脉冲,实现切向流条件下的穿孔板声学性能宽频带测量。研究切向流对穿孔板声阻抗的影响特征。研究结果表明,在1 500 Hz以下频段,穿孔板的声阻率随流速增大,而在1 500~4 000 Hz频段,声阻率随流速减小;切向流条件下的共振峰向高频偏移,吸声频带加宽。     

测量不确定度在农药残留分析测试中的应用

本文将对测量不确定度重要性进行阐述和探讨,并对NY/T761-2004农药残留分析结果进行实例分析评价。     

基于相关分析的交流电压测量

论述了将数采板与相关分析方法相结合,快速、准确测量交流电压的新方法,并给出了实用例证。     

Measurement Theory as an Independent Branch of Knowledge: Aims and Problems of Characterization

An analysis is made of measurement theory as an independent branch of knowledge and a list is given of theoretical problems which are exclusively specific to the theory and practice of measurements and are characteristic indicators of this theory. The essential cognitive nature of measurements is emphasized.     

基于约瑟夫森量子电压的谐波电压测量方法研究

约瑟夫森量子电压目前大多应用于正弦信号的测量,极少有针对谐波信号的研究。对可编程约瑟夫森电压基准应用于谐波检测的可行性进行了研究,实现谐波电压向量子电压过渡。在使用阶梯波交流量子电压进行谐波电压测量时,由于过渡过程和吉布斯现象的存在,部分数据出现较大波动;若将该部分处于过渡过程的数据纳入傅里叶变换,会导致恢复得到的信号幅值和相位失真。针对这一问题,提出了一种新的谐波电压计算方法:加权傅里叶变换。该方法通过将处于过渡过程的数据权重置零的方式,实现了谐波电压的准确测量。实验结果表明,谐波电压幅值和相位测量结果较理想,幅值测量标准差均小于1 μV,相位测量标准差均小于15 μrad。     

高温测量技术

文章针对铜液高温连续测量为目标,研制开发了特种连续测温传感器,并对铜液连续测温传感器的性能进行了全面的阐述,通过工业试验及应用,得出研究结果.铜液连续测温传感器在1200℃铜液中可持续工作三个月,温度差不大于2℃.     

高精度程控可调直流电压基准装置

本文介绍了ＡＤ６８８和ＡＤ６６０两种芯片的原理和特点，并介绍了一种采用ＡＤ６８８的±１０Ｖ输出作为ＡＤ６６０参考源的组合电路及其与８０３１单片机的接口。该电路产生的０～１０Ｖ程控可调直流电压，精度高，稳定性好，非常适合在高精度等级的标准信号源中作为直流电压基准。     

高精度交直流电压发生器的研制

本文叙述了一种高精度交直流电压发生器的原理及具体电路实现．其中包括数字正弦信号的合成、产生及其幅度频率控制．该系统的核心是一个二十位的脉冲调宽式Ｄ／Ａ转换器．交流幅度控制采用了采样保持型的闭环稳幅系统．     

Unifying Dynamic Temperature Measurements and Methods of Determining Complete Dynamic Characteristics for Primary Standard Water-Flow Thermometers

Instruments and methods are considered for unifying dynamic measurements on water stream temperatures and the transfer of the corresponding unit to fast temperature-pulsation thermometers for water flows.     

An Algorithm for Deriving the Measurement Equation and Estimating the Methodological Error (Uncertainty) in the Result for Indirect Measurements

An algorithm is proposed for deriving the measurement equation for indirect measurements, which is based on incorporating the features of the measurement object, the influencing factors in the transformation of the data-bearing signal as it passes from the object to the meter, and also the signal transformation in the meter. An example is given of distance measurement performed by means of electromagnetic waves in the optical range.__________Translated from Izmeritel’naya Tekhnika, No. 4, pp. 25–29, April, 2005.     

一种新型的交流阻抗计量标准装置

为解决任意阻抗模与阻抗角的交流阻抗的溯源问题,研制了一套新型交流阻抗标准装置,由交流阻抗标准源及交流阻抗标准表组成,在100Hz~1MHz、0.1Ω~1kΩ范围,可对RLC数字电桥、交流阻抗和实物阻抗进行校准,技术指标可以达到0.01%。采用直接测量法、替代测量法和等电位测量法,将交流阻抗标准溯源到实物阻抗标准、电压比例标准和相位标准上,形成了一条完整的交流阻抗溯源链。