A new conductivity detector for capillary electrophoresis consisting of an electrochemical cell and a conductive meter was developed. In the cell, the microelectrode and capillaryd were inserted through the cell wall ...A new conductivity detector for capillary electrophoresis consisting of an electrochemical cell and a conductive meter was developed. In the cell, the microelectrode and capillaryd were inserted through the cell wall and fixed by screws and sealing ring, the ends of microelectrode: and capillary were located by a guide with two cross holes. LOD for K+ was 1.5 x 10(-5) mol/L.展开更多
We report a resonant method to measure the wall capacitance（C_w） and solution resistance（R_S） in a capacitively coupled contactless conductivity detector（C^4D）.Under the typical operating conditions in capillary...We report a resonant method to measure the wall capacitance（C_w） and solution resistance（R_S） in a capacitively coupled contactless conductivity detector（C^4D）.Under the typical operating conditions in capillary electrophoresis（I.D.50μm,O.D. 360μm,electrode length of 4 mm,electrode gap of 1 mm,frequency of 200 kHz）,the values of C_w measured in 1 and 20 mmol/L NaCl solutions are 2.8 and 32 fF,which are only 1.1%and 12%of prediction by the equation in references,respectively.The value of R_S is less than the prediction in solutions withκ〈0.02 S/m.The response current of C^4D is due to the change in C_w because the total impedance of a C^4D is composed mainly by the impedance from C_w.展开更多
为实现无土栽培基质参数的快速准确测量,基于自制的基质多参数复合传感器,并结合Zig Bee无线网络技术,研制了便携式基质多参数无线检测仪。检测仪采用分体式设计,由无线复合传感器和手持终端两部分组成。无线复合传感器采集基质参数信息...为实现无土栽培基质参数的快速准确测量,基于自制的基质多参数复合传感器,并结合Zig Bee无线网络技术,研制了便携式基质多参数无线检测仪。检测仪采用分体式设计,由无线复合传感器和手持终端两部分组成。无线复合传感器采集基质参数信息,并以无线的方式将信息发送到手持终端;手持终端对接收到的测量参数信息进行处理分析、显示、存储和查询等。检测仪性能试验表明,含水率测量误差为-0.4%-3.1%,相对误差为-3.2%-9.6%,且对不同基质具有较好的适应性;电导率测量误差为-0.015-0.179 m S/cm,相对误差为-4.7%-10%,且对不同基质具有较好的适应性;温度测量误差为-0.63-0.69℃,相对误差为-1.1%-3.3%。检测仪能够满足无土栽培基质参数检测的要求。展开更多
基金This research was Supported partially by the National Natural Science Foundation of China!(Grant No.2967>033 ). We also thank e
文摘A new conductivity detector for capillary electrophoresis consisting of an electrochemical cell and a conductive meter was developed. In the cell, the microelectrode and capillaryd were inserted through the cell wall and fixed by screws and sealing ring, the ends of microelectrode: and capillary were located by a guide with two cross holes. LOD for K+ was 1.5 x 10(-5) mol/L.
基金supported by the National Natural Science Foundation of China(nos.20975062 and 21175084)
文摘We report a resonant method to measure the wall capacitance（C_w） and solution resistance（R_S） in a capacitively coupled contactless conductivity detector（C^4D）.Under the typical operating conditions in capillary electrophoresis（I.D.50μm,O.D. 360μm,electrode length of 4 mm,electrode gap of 1 mm,frequency of 200 kHz）,the values of C_w measured in 1 and 20 mmol/L NaCl solutions are 2.8 and 32 fF,which are only 1.1%and 12%of prediction by the equation in references,respectively.The value of R_S is less than the prediction in solutions withκ〈0.02 S/m.The response current of C^4D is due to the change in C_w because the total impedance of a C^4D is composed mainly by the impedance from C_w.
文摘为实现无土栽培基质参数的快速准确测量,基于自制的基质多参数复合传感器,并结合Zig Bee无线网络技术,研制了便携式基质多参数无线检测仪。检测仪采用分体式设计,由无线复合传感器和手持终端两部分组成。无线复合传感器采集基质参数信息,并以无线的方式将信息发送到手持终端;手持终端对接收到的测量参数信息进行处理分析、显示、存储和查询等。检测仪性能试验表明,含水率测量误差为-0.4%-3.1%,相对误差为-3.2%-9.6%,且对不同基质具有较好的适应性;电导率测量误差为-0.015-0.179 m S/cm,相对误差为-4.7%-10%,且对不同基质具有较好的适应性;温度测量误差为-0.63-0.69℃,相对误差为-1.1%-3.3%。检测仪能够满足无土栽培基质参数检测的要求。
