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利用ICP-OES和AAS测定18种辣椒中矿物质元素的对比探究

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广州化工 2023年第23期51卷 43-47,61页

作者：耿新华刘文峰吴启航秦冬冬关宏宇广州大学化学化工学院广东广州510006

分析了国内市场上常见的18种辣椒中19种矿物质元素的含量,其中使用湿消解和干灰化两种消化方法对辣椒样品进行前处理,再用电感耦合等离子体发射光谱法对18种元素进行检测,和用原子吸收分光光度法对钾元素进行检测。各元素的标液线性曲... 详细信息

分析了国内市场上常见的18种辣椒中19种矿物质元素的含量,其中使用湿消解和干灰化两种消化方法对辣椒样品进行前处理,再用电感耦合等离子体发射光谱法对18种元素进行检测,和用原子吸收分光光度法对钾元素进行检测。各元素的标液线性曲线的相关系数都大于0.99,两种消化方法测出的样品数据结果相近,干灰化法的实验效果优于湿消解法。检测结果可以评判所测辣椒的营养价值及其安全性,给人们的日常选购辣椒提供科学的参考。

关键词：辣椒矿物质元素前处理方法电感耦合等离子体光谱仪

Aero-engine fault diagnosis applying new fast support vector algorithm

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航空动力学报 2012年第7期27卷 1604-1612页

作者： XU Qi-hua geng Shuai SHI Jun College of Electronic Engineering Huaihai Institute of Technology Lianyungang Jiangsu 222005 China No. 365 Institute Northwestern Polytechnical University Xi'an 710072 China

A new fast learning algorithm was presented to solve the large-scale support vector machine ( SVM ) training problem of aero-engine fault *** relative boundary vectors ( RBVs ) instead of all the original training samples were used for the training of the binary SVM fault *** pruning strategy decreased the number of final training sample significantly and can keep classification accuracy almost *** , the training time was shortened to 1 / 20compared with basic SVM *** , owing to the reduction of support vector number , the classification time was also *** sample aliasing existed , the aliasing sample points which were not of the same class were eliminated before the relative boundary vectors were *** , the samples near the relative boundary vectors were selected for SVM training in order to prevent the loss of some key sample points resulted from *** can improve classification accuracy effectively.A simulation example to classify 5classes of combination fault of aero-engine gas path components was finished and the total fault classification accuracy reached 96.1%.Simulation results show that this fast learning algorithm is effective , reliable and easy to be implemented for engineering application.

关键词： aero-engine support vector machines fault diagnosis large-scale training set relative boundary vector sample pruning

Isoentropic and Isoenthalpic Temperatures of Protein Unfolding in Hydrophobic Interaction Chromatography

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Chinese Chemical Letters 2006年第1期17卷 105-108页

作者： Yah YAN Rui Xian LIU Yin Mao WEI Ye hua SHEN xin Du geng Institute of Modern Separation Science Northwest University Xi＇an 710069 Contemporary Educational Technology Center Northwest University Xi＇an 710069

The thermal behaviors of five proteins in hydrophobic interaction chromatography （HIC） were investigated in the temperature range from 0 to 50℃. The thermodynamic parameters （△H°,△S°, △Cp°and △G°） of these proteins in the process of retention and unfolding were determined. The existence of enthalpy and entropy convergence with temperature was confirmed. The differences of the isoentropic and isoenthalpic temperatures for protein unfolding in HIC system from the traditional solution were elucidated.

关键词： Column liquid chromatography hydrophobic interaction chromatography protein unfolding thermodynamic convergence.

高速沉积μc-Si：H薄膜生长机制及其微结构的研究

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光电子．激光 2008年第1期19卷 54-57页

作者：韩晓艳耿新华郭群超袁育杰候国付魏长春张晓丹孙建薛俊明赵颖蔡宁任慧志张德坤南开大学光电子薄膜器件与技术研究所光电信息技术科学教育部重点实验室光电子薄膜器件与技术天津市重点实验室天津300071

采用高压高功率的超高频等离子体增强化学气相沉积(VHF-PECVD)技术,在腐蚀后的7059玻璃、低晶化和高晶化的微晶硅(μc-Si:H)p型材料3种衬底上,通过改变沉积时间的方法,高速(沉积速率约为1nm/s)沉积了不同厚度的μc-Si:H薄膜材料。测试... 详细信息

采用高压高功率的超高频等离子体增强化学气相沉积(VHF-PECVD)技术,在腐蚀后的7059玻璃、低晶化和高晶化的微晶硅(μc-Si:H)p型材料3种衬底上,通过改变沉积时间的方法,高速(沉积速率约为1nm/s)沉积了不同厚度的μc-Si:H薄膜材料。测试其表面形貌及晶化率,比较了不同衬底上高速生长的μc-Si:H薄膜生长机制及微结构的差异,最后得到适于高速沉积pinμc-Si:H太阳电池的μc-Si:Hp型材料应具备的条件。

关键词：微晶硅薄膜(μc-Si:H) 微结构纵向均匀性衬底形貌

Regional gravity survey and application in oil and gas exploration in China

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China Geology 2019年第3期2卷 382-390页

作者： Ming-hua Zhang Ji-hua Qiao geng-xin Zhao Xue-yi Lan Development and Research Center China Geological SurveyMinistry of Natural ResourcesBeijing 100037China Tianjin Center China Geological SurveyMinistry of Natural ResourcesTianjin 300170China Anhui Academy of Geoexploration Hefei 230031China

Ground gravity survey for regional structure unit delineation and oil and gas exploration in China is addressed in this paper with examples. Gravity survey scales, coverage, technical regulations and achievements at the national level are introduced, including data processing and anomaly interpretation techniques. Bouguer anomalies of terrestrial territories of China and classification of anomalous feature zones are also described;they are well correlated with lithotectonical boundaries, fault zones, and unexposed igneous plutons. Recent study results of petroliferous sedimentary basins are presented as well, including concealed boundaries and major structures of large basins. It is concluded that gravity survey is the most effective and economic method in unveiling unexposed and deep-seated structures, targeting and delineating oil and gas-bearing sedimentary basins, and locating main trap structures within prolific basins in early stage of exploration in China. Suggestions for improving exploration of both conventional and unconventional oil and gas reservoirs in China are also given in the paper.

关键词： Concealed and deep-seated structures Oil and gas basins Gravity survey Data integration Deep oil and gas exploration engineering China

The flow characteristics around bridge piers under the impact of a ship

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Journal of Hydrodynamics 2020年第6期32卷 1165-1177页

作者： Yan-fen geng hua-qiang Guo xing Ke School of Transportation Southeast UniversityNanjing211189China

The complicated flow structure around the pier threatens the safe navigation of *** paper studies the mechanism of the flow with a ship around the pier,passing or not passing and with consideration of the interval between the ship and the *** flow field model and the moving ship model are constructed by the six degrees of freedom(6DOF)solver combined with the virtual unit immersed boundary method and the level set method,both of which are based on the three-dimensional Navier-Stokes *** simulation results show that the ship significantly influences the flow around the pier,increasing the flow velocity by 50%to 140%.Away from the bridge pier,the cross-flow velocity *** cross-flow velocity near the side of the pier also increases but in the opposite *** ship is affected by the negative yaw moment because of the reverse cross-flow between the pier and the *** size of the ship has an important impact on the extent of the affected flow areas but the velocity distribution is roughly in the same *** results show double impacts of ship and pier should be considered when determining the safe area of navigation.

关键词： Bridge pier flow around cylinder moving ship model

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常见植物对重金属铊吸收特征研究

广东农业科学 2018年第4期45卷 100-105页

作者：张福祎姚焱张平刘文峰耿新华黎秀苑刘芳广州大学生命科学学院广东广州510006 广州大学化学化工学院广东广州510006

利用水培试验方法,考察了4种常见植物对重金属铊两种价态Tl^+和Tl^(3+)的吸收速率、铊富集量,植物体内铊价态存在形式及K+影响Tl^+和Tl^(3+)在植物中的富集。结果表明,植物对Tl^+和Tl^(3+)的吸收速率与铊富集量在不同植物中表现不同。... 详细信息

利用水培试验方法,考察了4种常见植物对重金属铊两种价态Tl^+和Tl^(3+)的吸收速率、铊富集量,植物体内铊价态存在形式及K+影响Tl^+和Tl^(3+)在植物中的富集。结果表明,植物对Tl^+和Tl^(3+)的吸收速率与铊富集量在不同植物中表现不同。肾蕨表现出对Tl^+和Tl^(3+)的最大吸收速率,分别为0.004、0.007 mg/g·h。狐尾藻对Tl^(3+)的铊富集量最大,为681.97 mg/kg(DW);甘蓝对Tl^+的铊富集量最大,为473.30 mg/kg(DW)。植物对两种价态铊的吸收富集主要集中在根部。植物根部的铊价态分析表明,通过根系吸收进入植物体内的铊都以Tl^+为主要存在形式。当Tl^+/Tl^(3+)与K+比例为1∶25时,K+对Tl^+和Tl^(3+)都具有拮抗抑制作用,可以影响植物对Tl^+和Tl^(3+)的富集。

关键词：铊铊价态铊富集甘蓝钾

Effect of slag composition on elements oxidation behavior of GH984G superalloy for electroslag remelting withdrawal process

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Journal of Iron and Steel Research International 2022年第5期29卷 761-771页

作者： Fu-bin Liu Jun-zhe Gao Hai-bo Cao hua-bing Li Zhou-hua Jiang xin geng Cong-peng Kang Kui Chen Rui-dong An School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina Hefei Institutes of Physical Science Chinese Academy of SciencesHefei230031AnhuiChina

The composition of a slag system has been shown to be particularly important and influential for the new technology of electroslag remelting withdrawal *** oxidation of the GH984G alloy elements,in contact with different contents of CaF_(2)–CaO–Al_(2)O_(3)–MgO–TiO_(2)–SiO_(2)in various slag systems,has been investigated in the present study by performing slag–metal equilibrium experiments and ion and molecule coexistence theory *** results show that CaF_(2)and MgO have only a minor effect on the oxidation rates of Al and Ti in the GH984G ***,it was found that SiO_(2)would intensify the oxidation degree of Al and Ti,and Al was found to become easier oxidized than ***,CaO was found to reduce the activity of SiO_(2)and,thereby,also the oxidation degree of Al and ***,TiO_(2)was found to reduce the oxidation rate of Ti and instead increase the oxidation rate of ***,the effect of Al_(2)O_(3)on the oxidation of Al and Ti was observed to be opposite to that of TiO_(2).The calculated results were found to be in good agreement with experimental ***,viscosity experiments showed that CaO would rapidly increase the viscosity of the slag at low temperatures,and that the viscosity of the slag would increase with an increase in SiO_(2)content.

关键词： Electroslag remelting withdrawal Slag GH984G superalloy Oxidation rate Viscosity

Modeling framework of voltage-source converters based on equivalence with synchronous generator

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Journal of Modern Power Systems and Clean Energy 2018年第6期6卷 1291-1305页

作者： Shulong TAN hua geng geng YANG huai WANG Frede BLAABJERG Department of Automation Tsinghua University Department of Energy Technology Aalborg University

Along with the increasing penetration of distributed generation with voltage-source converters(VSCs),there are extensive concerns over the potential virtual rotor angle stability, which is characterized by oscillations of power and frequency during the dynamic process of synchronization in the grid. Several control strategies have been developed for VSCs to emulate rotating inertia as well as damping of oscillations. This paper classifies these strategies and provides a small-signal modeling framework including all kinds of VSCs in different applications for virtual rotor angle stability. A unified perspective based on the famous Phillips–Heffron model is established for various VSCs. Thus, the concepts of equivalent inertia and the synchronizing and damping coefficients in different VSCs are highlighted, based on the similarities with the synchronous generator(SG) system in both physical mechanisms and mathematical models. It revealed the potentiality of various VSCs to achieve equivalence with the SG. This study helps promote the unity of VSCs and traditional SGs in both theories and methods for analyzing the dynamic behavior and enhancing the stability. Finally,future research needs and new perspectives are addressed.

关键词： Voltage-source converter(VSC) Synchronous generator Virtual rotor angle stability Inertia Synchronizing Damping