离子色谱化学抑制器的进展

介绍了离子色谱化学抑制器的发展历史、发展现状和发展趋势，讨论了化学抑制器的类型及其特性。     

离子色谱仪自循环再生电抑制器性能测试与比较

对8种离子色谱自循环再生阴离子电抑制器的性能进行了测试,比较了抑制容量、柱效等指标。初步结果表明,国产阴离子电抑制器可以应用于实际离子色谱分析,有些品牌性能与进口产品已比较接近。     

50Hz工频抑制器设计与仿真

介绍了一种基于双T网络和运算放大器的工频信号抑制器的设计,用以消除测试试验中50 Hz干扰信号,包括工频信号抑制器的设计原理与参数计算,选择。利用信号发生器与示波器对电路进行滤波试验,并且与Dewe Soft数据采集仪的带阻功能进行比较。     

改进的国产WLK-6A型阴离子抑制器在戴安离子色谱系统中的使用

将改进的国产WLK-6A型阴离子抑制器应用于Dionex600型离子色谱系统,对基线噪声、基线漂移、重复性及实际样品测定中的线性、检出限等作了试验。结果表明,改进的WLK-6A型抑制器可以与戴安AS14A（3ITIm）、AS14A（4mm）柱子配套使用。     

高浓度氨水中痕量阴离子的测量研究及应用

利用自再生抑制器ASEN600对田湾核电站中所用的高浓度氨水溶液进行样品前处理后,通过离子色谱法成功的测定出了高浓度氨水溶液中的阴离子含量。将样品稀释至约1—5％左右浓度后,经过自再生抑制器ASRN300进行前处理,抑制器通过电解水和膜渗透将样品的pH中和至约为7,然后再将前处理后的样品上离子色谱进行分析,采用电解氢氧化钾作为淋洗液,可实现常见阴离子高灵敏度分析与检测,该方法重现性和线性好,且检测下限控制较低,各种阴离子的检测下限可达0．1μg／L级。     

离子色谱膜抑制器的工作原理、发展及应用

介绍了离子色谱膜抑制器的工作原理、发展过程及应用，引用文献力篇。     

TVS瞬态电压抑制器的特性及使用

介绍瞬态电压抑制器的主要参数、典型应用及选用指南。     

电子汽车衡的防雷装置

介绍电子汽车衡避雷所用的放电器和瞬时的抑制器,及它们的实际使用方法.     

Littelfuse紧凑型汽车级ESD抑制器在经受多次ESD冲击后仍可抵御高达30kV的瞬变

<正>2017年8月7日,全球电路保护领域的企业Littelfuse,Inc.推出了紧凑型表面贴装聚合物汽车级静电放电抑制器,能够保护敏感设备免受高达30 kV的接触放电/空气放电造成的危害。AXGD系列XTREME-GUARDTMESD抑制器专为高频高速应用而设计,提供高额定电压(最高达32VDC)和极端ESD保护要求。即使在经受多次ESD冲击后,仍能持续维持极低的     

利用国产离子色谱抑制器建立单泵柱切换系统

建立以国产离子色谱抑制器为基础的简化的离子排斥-离子交换柱切换系统,成功测定了高浓度弱酸基体中的痕量无机阴离子。与传统的柱切换系统相比,本系统只用一个泵;同时充分发挥了国产抑制器应用在单泵柱切换系统具有体积小、耐压性强、抑制作用好等优点。利用本系统,优化色谱条件,成功测定了酒石酸和柠檬酸中的氯离子、硫酸根离子和硝酸根离子,降低了方法的检出限(0.4～1.6μg/L,S/N=3),并获得了理想的回收率(78.2%～112.9%)。     

免试剂离子色谱测定阳离子中的离子抑制器应用研究

采用离子色谱法对矿泉水中的七种阳离子进行了定量分析研究，探讨了离子抑制反应对阳离子测定的影响以及阳离子响应电导和抑制电流强度的关系。实验中以选定的分析条件，测定了矿泉水中的七种阳离子进行了定量分析，测定了阳离子的回归方程、相关系数、线性范围、检测限和相对标准偏差。实验结果显示各个化合物回归方程的相关系数r为0．9943～0．9999，峰高相对标准偏差RSD％在0．80％-2.20％，回收率为93％-102％，满足定量分析要求。     

离子色谱仪使用常见问题分析及维护保养

离子色谱仪广泛应用于环境、食品、水质检测等领域,是高效液相色谱的一种,适用于亲水性阴、阳离子的分离。最基本的组件是流动相容器、高压输液泵、进样器、色谱柱、检测器和数据处理系统。本文例举了离子色谱仪使用过程中常见的问题,主要包括六通阀、电导池、平流泵、色谱柱、抑制器及整个流路等方面,针对这些问题,分析其产生的可能原因,并给出合理的解决方案,同时还介绍了相关仪器日常维护保养内容,具有一定参考价值。     

癌基因及其检测方法研究进展

肿瘤的发生是与肿瘤相关基因的行为有很大的关系。本文综述了癌基因和抑癌基因的定义,原癌基因的最新发现,抑癌基因的研究进展,以及现阶段对肿瘤相关基因检测方法。其中总结了关于甲基化检测作为肿瘤标志物的研究情况。     

消音器降噪与发动机噪声的分析与研究

通过所测试的发动机噪声频谱图,分析了在消音器的设计中,如何根据噪声极值的频率区域获得良好降噪效果的方法,从理论上分析了通过扩大降噪频率区域的途径来提高降噪效果的消音器结构和设计思路,通过所测试的该类消音器与其它类型消音器降噪频谱图的对比,验证了该类消音器良好的降噪效果.列出了10kW金牛柴油发动机的噪声频谱图,噪声极值为94dB;共振一扩张型消音器的降噪频谱图,噪声极值点的平均降噪量为17.94dB;扩张型消音器的降噪频谱图,噪声极值点的平均降噪量为11.5dB,通过频谱图的降噪对比,说明将共振和扩张特征在不同噪声极值频率区域的降噪极值相结合,可获得理想的降噪效果..     

Molecular orbital simulations on electron-induced degradation of perfluoropolyethers with several types of segments

Semi-empirical molecular orbital simulations on electron-induced degradation of perfluoropolyethers (PFPEs) with several types of segments, such as methylene oxide, ethylene oxide, ethylene oxide-methylene oxide, linear and branched propylene oxide, were carried out. The calculated heat of formation indicated that the anion radical states of these species had lower energy levels compared to neutral states. The paper postulates that electron attachment to PFPE easily occurs on electron-rich surfaces. The anion radical was supposed to decompose to an anion and a neutral radical, while the cation radical was expected to degrade to a cation and a neutral radical. The formation of carbonyl difluoride was simulated in the case of the decomposition of perfluoropropylene oxide cation radical.     

Prevention of air entrainment during liquid draining using disc-type vortex suppressor

After rotating a cylindrical tank containing a liquid at a constant rotation speed, by draining the liquid freely, an air-core phenomenon (that is, air is entrained into the drain port along a vortex flow) can be forcibly reproduced. This vortex phenomenon occurs very frequently in a variety of actual drainage situations and generally has a negative impact on many industrial devices, including reductions in drain speed, a noise and vibration, and structural damage of turbo machineries. The present study suggests a simple and very effective vortex-suppression device through physically analyzing the causes of the air-core phenomenon. In this study, liquid drainage processes with and without the suggested disc-type vortex suppressor were investigated numerically and experimentally. Through the numerical simulation, the internal flow characteristics have been investigated and the mechanism of the air-core formation has been revealed. As well, the experiments of varying the dimensions of the suggested disc-type vortex suppressor have been carried out. The velocity vector, drain water level, and vorticity distribution were compared for cases with and without the suggested vortex suppressor.     

儿茶酚胺类物质在阳离子交换树脂上的保留行为及其机理

发现了儿茶酚胺类物质在阳离子交换色谱过程中有“多峰现象”,即一种物质有两个或两个以上的色谱峰流出色谱柱。对这种“多峰现象”形成的机理进行了初步探讨。儿茶酚胺类物质在与阳离子交换树脂交换基进行交换过程中淋洗液酸度与乙腈的作用使一部分儿茶酚胺类物质发生电离,由于离子在阳离子交换树脂中的保留时间不同,导致了双峰出现。     

Erratum to: Response Characteristics of the Potential-Controlled Friction of ZrO<Subscript>2</Subscript>/Stainless Steel Tribopairs in Sodium Dodecyl Sulfate Aqueous Solutions

The tribological properties of room temperature ionic liquids containing tetraalkylphosphonium cations were evaluated on the basis of the chemical structure of their salts. The tribochemistry of these ionic liquids was discussed on the basis of the results of tribo-tests and surface analyses. The tribological properties of the tetraalkylphosphonium salts examined in this work were observed to be better than those of 1,3-alkylimidazolium salts. The structure of the alkyl group in the phosphonium cation also has a slight effect on the tribological properties of the salts. During a friction test carried out under low-load conditions, the phosphonium cation was oxidized to phosphate to form a boundary film. This film inhibited the reaction of the bis(trifluoromethanesulfonyl)amide anion that yielded metal fluoride on the rubbed surfaces. The combination of the phosphonium cation with a phosphate anion or thiophosphate anion resulted in a better lubricant than 1,3-alkylimidazolium bis(trifluoromethanesulfonyl)amide. The reactions of the phosphate anion and thiophosphate anion yielded a phosphate boundary film that exhibited better tribological properties than those of the fluoride boundary film.