The Experts below are selected from a list of 61368 Experts worldwide ranked by ideXlab platform
Yao Kong - One of the best experts on this subject based on the ideXlab platform.
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direct coupling of thin layer chromatography bioautography with Electrostatic Field induced spray ionization mass spectrometry for separation and identification of lipase inhibitors in lotus leaves
Analytica Chimica Acta, 2017Co-Authors: Lei Zhang, Jihe Tang, Zhihong Cheng, Jiyao Shi, Yao KongAbstract:In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via Electrostatic Field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MSn (n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
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direct coupling of thin layer chromatography bioautography with Electrostatic Field induced spray ionization mass spectrometry for separation and identification of lipase inhibitors in lotus leaves
Analytica Chimica Acta, 2017Co-Authors: Lei Zhang, Jihe Tang, Zhihong Cheng, Yao Kong, Xiaohui Lu, Tao WuAbstract:Abstract In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via Electrostatic Field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MS n ( n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
Lei Zhang - One of the best experts on this subject based on the ideXlab platform.
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direct coupling of thin layer chromatography bioautography with Electrostatic Field induced spray ionization mass spectrometry for separation and identification of lipase inhibitors in lotus leaves
Analytica Chimica Acta, 2017Co-Authors: Lei Zhang, Jihe Tang, Zhihong Cheng, Jiyao Shi, Yao KongAbstract:In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via Electrostatic Field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MSn (n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
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direct coupling of thin layer chromatography bioautography with Electrostatic Field induced spray ionization mass spectrometry for separation and identification of lipase inhibitors in lotus leaves
Analytica Chimica Acta, 2017Co-Authors: Lei Zhang, Jihe Tang, Zhihong Cheng, Yao Kong, Xiaohui Lu, Tao WuAbstract:Abstract In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via Electrostatic Field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MS n ( n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
Wansheng Zhao - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of the governing parameters of the Electrostatic Field induced electrolyte jet micro electrical discharge machining on the silicon wafer
Proceedings of the Institution of Mechanical Engineers Part B: Journal of Engineering Manufacture, 2018Co-Authors: Yaou Zhang, Ning Han, Xiaoming Kang, Shuhuai Lan, Wansheng ZhaoAbstract:Electrostatic Field–induced electrolyte jet micro electrical discharge machining relies on the cyclic and pulsating electrical discharge between the tip of the fine jet, and the workpiece to remove...
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the investigation of discharge restriction mechanism of the floating workpiece based Electrostatic Field induced electrolyte jet e jet edm
Journal of Materials Processing Technology, 2017Co-Authors: Yaou Zhang, Xiaoming Kang, Wansheng ZhaoAbstract:Abstract In this paper, issues concerning the discharge deviation of the Electrostatic Field-induced electrolyte jet (E-Jet) electrical discharge machining (EDM) have been discussed. To restrict the discharge deviations, the floating workpiece and the assisted tool electrode are introduced into the E-Jet EDM system. The experimental results have shown that the discharges can be restricted at the nearest point from the tip of the fine jet on the workpiece. The controllable cave and continuous homogeneous linear groove machined verified this method can prohibit the deviation of the discharges. The simulation results of electric parameters on the workpiece have demonstrated the induced electric potential, the electric Field intensity and the electric displacement Field intensity are distributed in concentric circles with the peak values at the centers and gradients sharply decreasing with the increase of distance away from the center. The simulation, together with the experimental results, has revealed the discharge concentration mechanism of this improved E-Jet EDM.
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the experimental investigation of Electrostatic Field induced electrolyte jet e jet micro electrical machining mechanism
The International Journal of Advanced Manufacturing Technology, 2016Co-Authors: Yaou Zhang, Ning Han, Xiaoming Kang, Kevin Wilt, Wansheng ZhaoAbstract:In this paper, issues concerning micro-discharge energy generation and micro-tool electrode manufacture in traditional micro-electrical discharge machining (EDM) are discussed, and a new Electrostatic Field-induced electrolyte jet (E-Jet) micro-electrical machining method is proposed. A major issue is that the discharge process is an extremely volatile way to remove material from a substrate, and because it happens on such a small scale it is difficult to distinguish the principal machining mechanism of this new discharge process. This paper investigates the machining mechanism by examining the topology and composition constitution of the machined surface obtained using NaCl solution and deionized water as the E-jet solution in positive-polarity and negative-polarity machining after both single and prolonged discharges. Different material removal mechanisms under different polarities and discharge times have been disclosed, and conclusions concerning the E-Jet EDM control conditions have been drawn.
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an experimental study on the effect of parameters on the depth of crater machined by Electrostatic Field induced electrolyte jet micro electrical discharge machining
Advances in Mechanical Engineering, 2016Co-Authors: Yaou Zhang, Ning Han, Xiaoming Kang, Wansheng ZhaoAbstract:Electrostatic Field–induced electrolyte jet micro electrical discharge machining depends on heat generated by the periodic pulsed discharge between the workpiece and the electrolyte fine jet from the tip of Taylor cone, induced by the intense electric Field, to erode the material from the workpiece. To further investigate the characteristics of this discharge process, with the NaCl solution as the Electrostatic Field–induced electrolyte jet electrolyte and the silicon wafer as the workpiece, the governing factors of machining polarity, nozzle-to-workpiece distance, voltage applied between positive and negative polarities, and the effect of concentration of the electrolyte on the depth of crater after a single Electrostatic Field–induced electrolyte jet discharge have been studied. The experimental results show that the average depth of crater increases with the increase in the voltage applied between the nozzle and the workpiece, and increases with the increase in the concentration of the electrolyte, but decreases with the increase in the distance between the nozzle and the workpiece. The results have also demonstrated that the polarity has no clear influence on the average depth of crater after a single discharge.
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the tool electrode investigation of Electrostatic Field induced electrolyte jet e jet electrical discharge machining
The International Journal of Advanced Manufacturing Technology, 2016Co-Authors: Yaou Zhang, Ning Han, Xiaoming Kang, Kevin Wilt, Wansheng ZhaoAbstract:This investigation addresses concerns in micro-electrical discharge machining (EDM) such as high tool electrode preparation cost, tool electrode wear, and tool electrode compensation by proposing a new Electrostatic Field-induced electrolyte jet tool electrode. This method utilizes the theory that in a strong direct current electric Field, the electrolyte at the capillary tube outlet can form a Taylor cone based on the balance of electric Field force and surface tension. Coupled with the increase of electric Field intensity, a very fine jet can eject from the tip of the Taylor cone, and this induced charge on the tip leads to a discharge to the workpiece which can remove debris from the workpiece surface. After the discharge, the induced charge at the tip is neutralized, leading to the surface tension outweighing the electric Field force and the withdrawal of the fine jet. As a result, the cyclic pulse discharge process is generated. During the process, the tip of the fine jet serves as the tool electrode. This paper identifies this cyclic pulse electrolyte jet tool electrode generation and discharge process in action and tests the machining ability of this tool electrode on a silicon wafer. This electrolyte jet tool is also shown to have no wear or compensation issues, and the cost compared to conventional EDM is shown to be small.
Tao Wu - One of the best experts on this subject based on the ideXlab platform.
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direct coupling of thin layer chromatography bioautography with Electrostatic Field induced spray ionization mass spectrometry for separation and identification of lipase inhibitors in lotus leaves
Analytica Chimica Acta, 2017Co-Authors: Lei Zhang, Jihe Tang, Zhihong Cheng, Yao Kong, Xiaohui Lu, Tao WuAbstract:Abstract In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via Electrostatic Field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MS n ( n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
Jihe Tang - One of the best experts on this subject based on the ideXlab platform.
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direct coupling of thin layer chromatography bioautography with Electrostatic Field induced spray ionization mass spectrometry for separation and identification of lipase inhibitors in lotus leaves
Analytica Chimica Acta, 2017Co-Authors: Lei Zhang, Jihe Tang, Zhihong Cheng, Jiyao Shi, Yao KongAbstract:In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via Electrostatic Field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MSn (n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
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direct coupling of thin layer chromatography bioautography with Electrostatic Field induced spray ionization mass spectrometry for separation and identification of lipase inhibitors in lotus leaves
Analytica Chimica Acta, 2017Co-Authors: Lei Zhang, Jihe Tang, Zhihong Cheng, Yao Kong, Xiaohui Lu, Tao WuAbstract:Abstract In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via Electrostatic Field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MS n ( n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
