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液质联用分析技术中的基质效应

中国新药杂志 2024年第10期33卷 1009-1020页

作者：冯媛媛田冶尹利辉宁保明中国食品药品检定研究院北京102629

液质联用技术因超高的灵敏度和特异性而广泛应用于微量、痕量物质的检测。但是液质联用会产生基质效应,尤其在复杂基质下会严重影响结果的可靠性,具体表现为离子抑制或离子增强现象。为了克服这种干扰,在进行质谱分析前,要对基质效应进... 详细信息

液质联用技术因超高的灵敏度和特异性而广泛应用于微量、痕量物质的检测。但是液质联用会产生基质效应,尤其在复杂基质下会严重影响结果的可靠性,具体表现为离子抑制或离子增强现象。为了克服这种干扰,在进行质谱分析前,要对基质效应进行考察来保证结果的准确性。考察基质效应主要分为评价和克服两部分,目前常用的评价方法为柱后注射法、提取后添加法和斜率分析法。克服基质效应分为减小基质效应和补偿基质效应,减小基质效应可以通过前处理方法、优化色谱和质谱条件来实现,补偿基质效应通过合适的校准方法消除基质效应的干扰。本文对基质效应的机制、评价、消除/补偿进行综述,尝试建立发现、消除/补偿基质效应的方法。

关键词：基质效应机制评价清除

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首批阿戈美拉汀国家对照品的研制

中国新药杂志 2024年第14期33卷 1482-1488页

作者：孙长迎文强张燕霞尹利辉中国食品药品检定研究院北京102629 国家药品监督管理局化学药品质量研究与评价重点实验室北京102629 江苏豪森药业集团有限公司连云港222000

目的:建立定性和定量用阿戈美拉汀的首批国家对照品。方法:应用IR光谱、气质联用及NMR技术对阿戈美拉汀进行结构确证。采用HPLC法测定纯度并且对均匀性、稳定性进行研究,并测定干燥失重、炽灼残渣、热重分析等,通过质量平衡法计算阿戈... 详细信息

目的:建立定性和定量用阿戈美拉汀的首批国家对照品。方法:应用IR光谱、气质联用及NMR技术对阿戈美拉汀进行结构确证。采用HPLC法测定纯度并且对均匀性、稳定性进行研究,并测定干燥失重、炽灼残渣、热重分析等,通过质量平衡法计算阿戈美拉汀含量。结果:确证阿戈美拉汀的结构,确定首批阿戈美拉汀对照品含量为99.9%,与核磁定量法测定的结果、高氯酸非水滴定结果、差示扫描量热法(differential scanning calorimetry, DSC)结果基本一致。结论:首批阿戈美拉汀国家对照品的研制可作为阿戈美拉汀原料及其相关制剂的鉴别和含量测定用对照品。

关键词：阿戈美拉汀对照品含量测定 HPLC法质量平衡法

APPliCATION OF INTEGER CODING ACCELERATING GENETIC ALGORITHM IN RECTANGULAR CUTTING STOCK PROBLEM

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Chinese Journal of Mechanical Engineering 2006年第3期19卷 335-339页

作者： FANG hui yin Guofu li Haiqing PENG Biyou School of Manufacturing Science and Technology Sichuan University Chengdu 610065 China

An improved genetic algorithm and its application to resolve cutting stock problem arc presented. It is common to apply simple genetic algorithm （SGA） to cutting stock problem, but the huge amount of computing of SGA is a serious problem in practical application. Accelerating genetic algorithm （AGA） based on integer coding and AGA＇s detailed steps are developed to reduce the amount of computation, and a new kind of rectangular parts blank layout algorithm is designed for rectangular cutting stock problem. SGA is adopted to produce individuals within given evolution process, and the variation interval of these individuals is taken as initial domain of the next optimization process, thus shrinks searching range intensively and accelerates the evaluation process of SGA. To enhance the diversity of population and to avoid the algorithm stagnates at local optimization result, fixed number of individuals are produced randomly and replace the same number of parents in every evaluation process. According to the computational experiment, it is observed that this improved GA converges much sooner than SGA, and is able to get the balance of good result and high efficiency in the process of optimization for rectangular cutting stock problem.

关键词： Accelerating genetic algorithm Efficiency of optimization Cutting stock problem

Colorimetric and fluorescent detection of biological thiols in aqueous solution

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Chinese Chemical Letters 2013年第2期24卷 96-98页

作者： yin-hui li Jin-Feng Yang Chang-hui liu Ji-Shan li Rong-Hua Yang State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan University Anesthesia Department Affilicated Cancer HospitalXiangya School of Medicine.Central South University

Received 10 December 2012 Received in revised form 5 January 2013 Accepted 10 January 2013 Available online 8 February 2013

关键词： ColorimetryFluorescenceBiological thiolsMichael addition

A new synthesis of alkynyl tellurides promoted by CsOH and 4  MS

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Chinese Chemical Letters 2008年第12期19卷 1401-1402页

作者： yin hui li Jian Ping li Xiang Xia Kang Bing Zou Ruo Xin li Xin Hua Xu College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China The First Affiliated Hospital College of Medical Science Zhejiang University Hangzhou 310003 China

The mixture of cesium hydroxide and terminal alkynes in dry DMF in the presence of 4 A molecular sieves was stirred for 3.0 h at room temperature under N2, then aryltellurenyl bromide in THF was added, and the reactio... 详细信息

关键词： Cesium hydroxide Terminal alkynes Alkynyl telluiride

Tuning heterogeneous microstructures to enhance mechanical properties of nano-TiN particle reinforced Haynes 230 composites by laser powder bed fusion

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Rare Metals 2024年第9期43卷 4548-4565页

作者： Wen-Jie liu hui li Qian-Xing yin He-Jun Du School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China School of Mechanical&Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

Laser powder bed fusion(LPBF)is considered to be one of the most promising additive manufacturing technologies for producing components with geometries and high geometrical precision that are unattainable by traditional *** superalloy exhibits exceptional mechanical and high-temperature performances,rendering it a prime candidate for advanced aero-engine *** the high demand for LPBF-manufactured superalloys,the superalloy is one of the materials manufactured difficultly by LPBF due to their large laser absorptivity fluctuation,poor molten pool stability and sharp temperature ***,superalloys are characterized by severe pores,undesirable coarse columnar grains and poor mechanical *** this work,the effect of nano-TiN particles on defects,molten pool characteristics and microstructure and performance of the composites were *** 4.5 wt%TiN/Haynes230 samples exhibited exceptional nanohardness and elastic modulus with maximum values reaching 5.53 GPa and 240.03 GPa,*** superior mechanical properties were attributed to the combined effects of spatter and gas pore inhibition,grain refinement and duplex nanophases ***,the stability of molten pool was enhanced,and spatter was effectively suppressed by adding nano-TiN particles,while grain refinement and columnar to equiaxed transitions were ***,the matrix exhibited a high dislocation density due to a significant hindrance of dislocation movement caused by massive nano-phases(e.g.,TiN and M_(23)C_(6)),resulting in the formation of extensive dislocation tangles and *** work offers novel insights into the role of nanoparticles reinforced superalloy composites by LPBF.

关键词： Composites Laser powder bed fusion Molten pool characteristics Microstructure Mechanical properties

Constructing a 3D multichannel structure to enhance performance of Ni–Co–Mn hydroxide electrodes for flexible supercapacitors

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Rare Metals 2024年第1期43卷 148-163页

作者： Zhi-hui Xu Shi-Shuai Sun Xue-Lei li Zhi-hui Zhang Hai-ying li Shuang-Ting Ruan Shou-Gen yin Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)and Tianjin Key Laboratory for Photoelectric Materials and Devices School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China College of Science Tianjin University of TechnologyTianjin 300384China School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China

The balancing of the electrochemical performance,mechanical stability,and processing technology for applying supercapacitors to flexible and wearable electronics continues to encounter severe ***,we prepare Ni-Co-Mn hydroxide electrodes with a threedimensional multichannel structure via a simple hydrothermal *** are constructed using vertically contiguous nano sheets with a uniform thickness and rough *** electrodes can provide numerous electroactive sites and accelerate the transmission of electrolyte *** relationship between the structure and electrochemical performances is verified by experiments and theoretical ***-dimensional(2D)planar and one-dimensional(1D)fiber electrodes are prepared using a flexible carbon cloth(CC)and carbon fiber(CF),respectively,as *** assembled quasi-solid-state flexible asymmetric supercapacitor(FASC)with a twodimensional sandwich structure using NiCoMn-OH/CC as the electrode achieves a remarkable energy density of73.8 Wh·kg^(-1)at a power density of 1.03 kW·kg^(-1).The quasi-solid-state FASC with a 1D linear structure using NiCoMn-OH/CF as the electrode also attains a high energy density(12.9 Wh·kg^(-1)at a power density of0.75 W·kg^(-1)).Moreover,the electrochemical performances of the NiCoMn/CC//AC/CC and NiCoMn/CF//AC/CF FASCs are not disturbed at different bending angles(0°,45°,90°,135°and 180°),This indicates the superior flexibility of the *** also assemble a self-powered energy-harvesting storage system by integrating FASCs and commercial solar cells to verify its *** displays sustainable development potential for energy storage.

关键词： Supercapacitors Flexible Ni–Co–Mn hydroxide 3D multichannel structure High performances

Mitigation of Deane and Hamill phenomenon in gallium nitride high-voltage power supply for electric propulsion system application

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High Voltage 2024年第1期9卷 252-265页

作者： Minghai Dong hui li Shan yin Kye Yak See yingzhe Wu Xiong Xin School of Aeronautics&Astronautics University of Electronic Science and Technology of ChinaChengduChina School of Electrical&Electronic Engineering Nanyang Technological UniversitySingaporeSingapore School of Automation Engineering University of Electronic Science and Technology of ChinaChengduChina Innoscience(Shenzhen)Semiconductor Co.Ltd. ShenzhenChina

The step-up resonant converters are widely adopted to provide high voltage in kV-level for electric propulsion system due to their high efficiency,low mass,modularisation,and high-power *** bipolar Cockcroft-Walton voltage multiplier(BiCWVM)is a major circuit that steps up the voltage in the resonant ***,the diode nonlinearity in BiCWVM can introduce self-sustained quasi-periodic oscillations in the voltage and current waveforms,which is commonly known as the Deane and Hamill(DH)*** oscillation can lead to higher magnetic loss and control failure,and it is more likely to present in the gallium nitride-based converter due to the highfrequency *** authors aim to investigate and mitigate the DH phenomenon systematically so that proper mitigation can be *** facilitate the investigation,the circuit before the BiCWVM in the converter is derived and modelled as a voltage source v_(m)and a series inductor L_(sy).Also,the reverse recovery process of the diode in the BiCWVM can be represented by a piecewise-linear(PWL)model,with the simplified circuit and PWL model,the relationship between voltage and current under different operating conditions can be determined with *** relationship allows to understand the mechanism of diode reverse recovery in BiCWVM that leads to DH ***,a hybrid-/full-silicon carbide(SiC)design is proposed to mitigate the DH phenomenon,which is verified experimentally for a 300-kHz,5-W,20-V/1.5-kV GaN-based step-up resonant converter.

关键词： power resonant high

Effects of IGF-1 and oxLDL on expression of phosphatase PHLPP1 in vascular smooth muscular cells

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Journal of Geriatric Cardiology 2009年第4期6卷 237-240页

作者： Xing-li Wu Ding-You Yang Zhong-Su Yang De-yin li hui-Bin Xu Shi-Wen Wang Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China

Objective To investigate the effects of insulin-like growth factor-1 （IGF-1） and oxidized low density lipoprotein （oxLDL） on expression ofphosphatase PHLPP 1 in vascular smooth muscle cells （VSMCs）. Methods Rabbit aortic VSMCs were cultured. VSMCs proliferation ability was determined by measuring cell number and mitochondrial dehydrogenase （MD） activity with MTT assay. Western blot was used to detect the protein expression ofphosphatase PHLPP1. Results IGF-1 （100ug/L） increased cell number and MD activity to 3.02 and 3.59 times of that in control group, oxLDL（501xg/ml） elevated the above two parameters to 2.03 and 2.91 times respectively. Western blot showed that IGF-1 and oxLDL inhibited the expression of PHLPPI to 39.27% and 40.26% of the control group （P〈0.01 ）. Conclusion IGF- 1 and oxLDL may enhance the proliferation of VSMCs by decreasing the expression ofphosphatase PHLPP 1.

关键词： PH domain leucine-rich repeat protein phosphatasel (PHLPP1) insulin-like growth factor-l oxidized low density lipoprotein(oxLDL) vascular smooth muscle cells