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7种不同物质标定EDTA标准滴定溶液的条件控制及误差分析

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冶金分析 2007年第4期27卷 65-71页

作者：蔡成翔甘雄百色学院化学与生命科学系钦州学院化学与生物系

本文通过CaCO3,MgO,FeNH4(SO4)2.12H2O、锌粒、铜粒、铅粒、铋粒等7种物质在不同条件下对EDTA标准滴定溶液的标定对比试验,研究了酸效应、水解效应、温度、光照、空气浮力、基准物质溶液的配制和酸度的初调、缓冲溶液、指示剂的种类和... 详细信息

本文通过CaCO3,MgO,FeNH4(SO4)2.12H2O、锌粒、铜粒、铅粒、铋粒等7种物质在不同条件下对EDTA标准滴定溶液的标定对比试验,研究了酸效应、水解效应、温度、光照、空气浮力、基准物质溶液的配制和酸度的初调、缓冲溶液、指示剂的种类和用量等多种因素对标定误差的影响及其消除办法。实验结果表明,只要选择和控制好测定条件,标定方法之间的误差是可以减小或消除的。在本实验条件下,用上述7种物质标定0.020015mol/LEDTA标准滴定溶液,相对误差均小于0.20%。

关键词： EDTA标准滴定溶液标定误差分析

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高速铁路框架型板式轨道动力学分析

振动工程学报 2011年第2期24卷 164-169页

作者：蔡成标徐鹏西南交通大学牵引动力国家重点实验室四川成都610031

建立了高速列车-框架型板式轨道的动力学模型。基于弹性薄板振动理论和加权余量法,推导了框架型轨道板关于振型坐标的常微分方程。对比分析了运行速度为300 km/h的CRH 2-300动车组作用下框架型和平板型板式轨道动力响应,结果表明:两种... 详细信息

建立了高速列车-框架型板式轨道的动力学模型。基于弹性薄板振动理论和加权余量法,推导了框架型轨道板关于振型坐标的常微分方程。对比分析了运行速度为300 km/h的CRH 2-300动车组作用下框架型和平板型板式轨道动力响应,结果表明:两种轨道结构的钢轨垂向位移、钢轨支点反力差别不大,框架型板式轨道的轨道板垂向位移、CA砂浆动应力均大于平板型。分析了CA砂浆弹性模量、板下胶垫刚度对框架型板式轨道动力响应的影响,计算了框架型轨道板的动应力分布,结果表明:随CA砂浆弹性模量的增大,框架型轨道板垂向位移减小,CA砂浆动应力增大,对钢轨垂向位移和钢轨支点反力影响不大;增设板下胶垫可以有效降低CA砂浆动应力;框架型轨道板最大拉应力小于混凝土抗拉强度标准值,可保证强度。

关键词：列车框架型板式轨道开孔板动力响应

弹性支承块式无砟轨道结构参数动力学优化设计

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铁道学报 2011年第1期33卷 69-75页

作者：蔡成标徐鹏西南交通大学牵引动力国家重点实验室四川成都610031 西南交通大学高速铁路线路工程教育部重点实验室四川成都610031

建立车辆-弹性支承块式无砟轨道耦合动力学模型。模拟落轴试验荷载条件,分析轨下刚度与块下刚度的匹配关系,得出轨下刚度与块下刚度的合理取值范围。在轨道刚度确定的前提下,提出不同运营条件下满足动态轨距扩大限值的弹性支承块式无砟... 详细信息

建立车辆-弹性支承块式无砟轨道耦合动力学模型。模拟落轴试验荷载条件,分析轨下刚度与块下刚度的匹配关系,得出轨下刚度与块下刚度的合理取值范围。在轨道刚度确定的前提下,提出不同运营条件下满足动态轨距扩大限值的弹性支承块式无砟轨道合理结构参数。评估不同半径曲线上铺设弹性支承块式无砟轨道时重载货车和快速客车的运行安全性和舒适性。研究隧道内弹性支承块式无砟轨道与隧道外有砟轨道过渡段动力学问题,结果表明:将有砟轨道向隧道内延伸一定长度可明显改善连接处轨枕的受力状况,同时使支承块免受雨水侵蚀。延伸段长度以10～20 m为宜。

关键词：车辆-轨道耦合动力学弹性支承块式无砟轨道结构参数优化设计

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke cai Youluan Lu Fanpeng cheng Lijuan Shi Qun Yi Yao Liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction

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98号汽油的开发与质量控制

石油炼制与化工 2005年第5期36卷 34-37页

作者：蔡铖镇海炼油化工股份有限公司宁波315207

为适应市场和企业效益的需要,镇海炼油化工股份有限公司近年来逐步调整汽油产品结构,增产高牌号清洁汽油。经过对汽油组分质量进行控制和汽油调合方案的优化,生产出高标准98号汽油,其主要质量指标达到了预期目标:芳烃含量、RON优于符合... 详细信息

为适应市场和企业效益的需要,镇海炼油化工股份有限公司近年来逐步调整汽油产品结构,增产高牌号清洁汽油。经过对汽油组分质量进行控制和汽油调合方案的优化,生产出高标准98号汽油,其主要质量指标达到了预期目标:芳烃含量、RON优于符合欧Ⅲ排放标准的汽油,硫含量、蒸气压、苯含量与符合欧Ⅲ排放标准的汽油一致,满足了高档轿车对高品质汽油的需求。

关键词：汽油产品结构质量指标调合组分终馏点胶质指标硫含量指标诱导期指标烯烃指标储运系统

Ge/Si半导体量子点的应变分布与平衡形态

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物理学报 2007年第8期56卷 4841-4846页

作者：蔡承宇周旺民浙江工业大学机电工程学院杭州310032

基于各向异性弹性理论的有限元方法,研究了金字塔形自组织Ge/Si半导体量子点应变能随高宽比变化的规律:系统的应变能随着高宽比的增大而逐渐减小.并通过自由能(应变能与表面能之和)讨论了量子点的平衡形态.结果表明,对于固定体积的量子... 详细信息

基于各向异性弹性理论的有限元方法,研究了金字塔形自组织Ge/Si半导体量子点应变能随高宽比变化的规律:系统的应变能随着高宽比的增大而逐渐减小.并通过自由能(应变能与表面能之和)讨论了量子点的平衡形态.结果表明,对于固定体积的量子点,存在一个高宽比值,称之为平衡高宽比,使得系统的自由能最低.同时,还给出了量子点的应力、应变、流体静应变及双轴应变分布.这些可以作为阐明应变自组织量子点实验的理论基础.

关键词：量子点应变分布自由能平衡形态

Investigation on cyanobacterial production of the proposed neurotoxinβ-N-methylamino-L-alanine(BMAA)

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Water Biology and Security 2023年第4期2卷 128-135页

作者： Zi-Qian Wang Suqin Wang Ju-Yuan Zhang Gui-Ming Lin Nanqin Gan Lirong Song Xiaoli Zeng cheng-cai Zhang State Key Laboratory of Freshwater Ecology and Biotechnology and Key Laboratory of Algal Biology Institute of HydrobiologyChinese Academy of SciencesWuhan430072PR China University of Chinese Academy of Sciences Beijing100049PR China Institut AMU-WUT Wuhan University of TechnologyWuhanPR China

β-N-methylamino-L-alanine(BMAA)is an environmental neurotoxin thought to be produced by ***,the cyanobacterial origin of BMAA remains *** detection method and culture conditions of cyanobacteria are often cited as factors behind the discrepancy of published *** showed previously that BMAA was highly toxic to the cyanobacterium Nostoc PCC 7120,and it is taken up via an amino acid transport *** a mutantΔnatAΔbgtA deficient in amino acid transport as a genetic control,we show here that BMAA taken up from the medium can be detected quantitatively at a threshold similar to,or below those reported,but was undetectable in the *** BMAA isomer,2,4-diaminobutanoic acids(DAB),but not BMAA,could be detected in cell free extracts of Nostoc PCC ***-term(20 days)diazotrophic growth or nonlimiting supply of phosphate,conditions reported to enhance BMAA synthesis,did not lead to the detection of *** UPLC-MS/MS signal with a similar retention time to BMAA was found after prolonged diazotrophic incubation,but did not have fragment ions of BMAA after further *** extended to 29 different cyanobacterial strains and 6 natural cyanobacterial bloom samples,none of them was found to produce *** cytotoxicity of BMAA to cyanobacteria,and the lack of a cellular protective mechanism against such toxicity,contradict the presence of a BMAA synthesis pathway in these *** specific methods for BMAA detection in vivo need to be developed to clarify the cyanobacterial origin of BMAA.

关键词： Neurodegenerative disease Cyanobacteria BMAA detection Algal bloom

Identification and characterization of toxins in the venom gland of the Chinese bird spider, Haplopelma hainanum, by transcriptomic analysis

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Insect Science 2016年第3期23卷 487-499页

作者： Ting-cai cheng Ren-Wen Long Yu-Qian Wu You-Bing Guo Duo-Lian Liu Li Peng Dai-Qin Li Dai-Wen Yang Xin Xu Feng-Xiang Liu Qing-You Xia State Key Laboratory of Silkworm Genome Biology College of Biotechnology Southwest University Chongqing China Departmentof Biological Sciences National University of Singapore Singapore Singapore College of Life Sciences Hunan Normal UniversityChangsha China College of Life Sciences Hubei University Wuhan China

Tarantula venoms provide a model system for studying toxin selectivity, structure-activity relationships and molecular evolution ofpeptide toxins. Previous studies have identified a large number of peptide toxins in the venom of the Chinese bird spider Haplopelma hainanum, generally regarded as a highly venomous spider. However, the lack of available RNA-seq transcriptomic and genomic data is an obstacle to understanding its venom at the molecular level. In this study, we investigated the venom gland transcriptome of/-/, hainanum by RNA-seq, in the absence of an available genomic sequence. We identi- fied 201 potential toxins among 57 18 l de novo assembled transcripts, including knottins, Kunitz-type toxins, enzymes and other proteins. We systematically identified most of the knottins and Kunitz-type toxins, some of which showed strongly biased expression in the venom gland, including members of the huwentoxin-1, huwentoxin-2 and magi-1 families. We also discovered several novel potential toxins. These data demonstrate the high molec- ular and structural diversity in the venom toxins ofH. hainanum. This study offers a useful strategy for exploring the complex components of spider venoms.

关键词： diversity Haplopelma hainanum tarantula venom toxin transcriptome

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新生儿急性肾衰竭的连续性肾脏替代治疗

中华实用儿科临床杂志 2017年第2期32卷 84-87页

作者：蔡成上海交通大学附属儿童医院上海市儿童医院新生儿科200062

新生儿急性肾衰竭（acute renal failure，ARF）是多种因素导致的新生儿常见危重症，表现为肾功能急剧下降，短时间内血清肌酐进行性升高和尿量减少。新生儿ARF目前暂无有效的防治措施。近年来，血液净化技术发展迅速，连续性肾脏替代... 详细信息

新生儿急性肾衰竭（acute renal failure，ARF）是多种因素导致的新生儿常见危重症，表现为肾功能急剧下降，短时间内血清肌酐进行性升高和尿量减少。新生儿ARF目前暂无有效的防治措施。近年来，血液净化技术发展迅速，连续性肾脏替代治疗（continuous renal replacement therapy，CRRT）应用范围已从儿童ARF发展到新生儿ARF。现就新生儿ARF的高危因素、诊断标准、CRRT治疗的相关问题等进行阐述。

关键词：肾衰竭婴儿新生连续性肾脏替代治疗