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The autophagy-lysosome pathway:a potential target in the chemical and gene therapeutic strategies for Parkinson’s disease
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作者 Fengjuan Jiao Lingyan Meng +1 位作者 Kang Du Xuezhi Li 《Neural Regeneration Research》 SCIE CAS 2025年第1期139-158,共20页
Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular... Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular degradation pathways,the autophagy-lysosome pathway plays an important role in eliminating these proteins.Accumulating evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance ofα-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson’s disease.Moreover,multiple genes associated with the pathogenesis of Parkinson’s disease are intimately linked to alterations in the autophagy-lysosome pathway.Thus,this pathway appears to be a promising therapeutic target for treatment of Parkinson’s disease.In this review,we briefly introduce the machinery of autophagy.Then,we provide a description of the effects of Parkinson’s disease–related genes on the autophagy-lysosome pathway.Finally,we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy–lysosome pathway and their applications in Parkinson’s disease. 展开更多
关键词 AUTOPHAGY chemical therapy gene therapy Parkinson’s disease Α-sYNUCLEIN
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S-T-S混合式循环互助教学模式用于少学时“化工原理”课程
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作者 吕玲 《教育教学论坛》 2024年第31期157-160,共4页
“化工原理”课程是化工及相关专业的专业基础课程,相关专业的学时少,课程难,需重点解决的问题是“三多”“三不愿”“三不明”。针对痛点问题,提出了线上线下混合式循环互助的创新设计思路,包括:教师帮助学生自制课前、课中、课后习题... “化工原理”课程是化工及相关专业的专业基础课程,相关专业的学时少,课程难,需重点解决的问题是“三多”“三不愿”“三不明”。针对痛点问题,提出了线上线下混合式循环互助的创新设计思路,包括:教师帮助学生自制课前、课中、课后习题,学生帮助教师反馈真实学习情况,学生帮助学生组团互助学习。问卷调查和评教结果显示,在一定程度上解决了“三多”“三不愿”的问题;通过建立“助教团队”反馈不同层次学生的学习情况,较好地解决了“三不明”的问题。学生的成绩与教改前相比有明显提高。 展开更多
关键词 线上线下 s-T-s教学模式 化工原理 痛点问题
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Two chemical mutagens modulate the seed germination,growth,and phenotypic characteristics of Chinese fir(Cunninghamia lanceolata) 被引量:1
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作者 Sen Cao Ruiyang Hu +9 位作者 Xialei Wu Yuhan Sun Bo Wu Hongjing Duan Huazhong Lin Mingjing Wu Luming Fang Xiaolong Yu Wei Wu Yun Li 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第5期2077-2085,共9页
Chinese fir(Cunninghamia lanceolata(Lamb.)Hook),a fast-growing and economically important timber tree species in China,is widely used in construction,furniture,and paper manufacture but has a long breeding cycle.Chemi... Chinese fir(Cunninghamia lanceolata(Lamb.)Hook),a fast-growing and economically important timber tree species in China,is widely used in construction,furniture,and paper manufacture but has a long breeding cycle.Chemical mutagens,such as ethyl methane sulfonate(EMS)and sodium azide(SA),are widely used in crops such as rice,wheat,cotton,soybean and sugarcane but their utility for tree breeding is unknown.In this study we examined the effects of EMS and S A on Chinese fir seed germination and growth.Chinese fir seeds were treated with the two chemical mutagens;were planted in Jiangle County,Fujian Province,China;and their heights were measured from 2011 to2017.The concentrations and durations of treatment with the two chemical mutagens were significantly associated with the Chinese fir seedling and mortality rates,as well as with the heights of trees from the seedling stage to 3 years old.We also generated 127 mutants with abnormal branches and reproductive growth.We report here the effects of two chemical mutagens on Chinese fir breeding;our data will contribute to knowledge of the utility of EMS and SA in forestry. 展开更多
关键词 chemical mutagens Chinese fir seedling growth seedling rate MUTANTs
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Reliability Based Analysis of Ground Improvement Using a Polymeric Chemical Stabilizer
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作者 Bright Worlu Ify L. Nwaogazie 《Open Journal of Civil Engineering》 CAS 2023年第1期127-138,共12页
In view of the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them, there is a need to investiga... In view of the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them, there is a need to investigate modern trends in ground improvement techniques in order to determine their reliability. This study is thus aimed at using the reliability based approach to analyze the use of polyvinyl alcohol (PVA) in combination with 1,2,3,4 Butane-tetracarboxylic acid (BTCA) for ground improvement. This study is necessary given the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them. Simplex lattice design was employed to build the design of experiment before experimental investigations were carried out on the PVA-BTCA treated soft soils. Reliability indices were computed on the basis of the 28<sup>th</sup> day unconfined compressive strength (UCS) of the treated soil. Reliability index models were developed using the Scheffe’s technique and optimized using excel solver. From analysis of results, reliability model developed proved adequate at 5% level of significance. PVA-BTCA combination provided a potential reliability or probability of success of 99.936% at components combination of: 98.4256% for soil, 1.2352% for PVA, 0.3392% for BTCA and 15.9934% for water. It was therefore recommended that financial implications of using PVA-BTCA for stabilization be compared to those of conventional methods, in order to compare their performance-cost ratio. 展开更多
关键词 RELIABILITY Polyvinyl Alcohol (PVA) Butane-tetracarboxylic Acid (BTCA) Polymeric chemical scheffe’s simplex Technique
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S-doped mesoporous graphene modified separator for high performance lithium-sulfur batteries
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作者 Xinlong Ma Chenggen Xu +8 位作者 Yin Yang Dong Sun Kai Zhao Changbo Lu Peng Jin Yiting Chong Sirawit Pruksawan Zhihua Xiao Fuke Wang 《Materials Reports(Energy)》 EI 2024年第3期60-68,共9页
Due to their low cost,environmental friendliness and high energy density,the lithium-sulfur batteries(LSB)have been regarded as a promising alternative for the next generation of rechargeable battery systems.However,t... Due to their low cost,environmental friendliness and high energy density,the lithium-sulfur batteries(LSB)have been regarded as a promising alternative for the next generation of rechargeable battery systems.However,the practical application of LSB is seriously hampered by its short cycle life and high self-charge owing to the apparent shuttle effect of soluble lithium polysulfides.Using MgSO_(4)@MgO composite as both template and dopant,template-guided S-doped mesoporous graphene(SMG)is prepared via the fluidized-bed chemical vapor deposition method.As the polypropylene(PP)modifier,SMG with high specific surface area,abundant mesoporous structures and moderate S doping content offers a wealth of physical and chemical adsorptive sites and reduced interfacial contact resistance,thereby restraining the serious shuttle effects of lithium polysulfides.Consequently,the LSB configured with mesoporous graphene(MG)as S host material and SMG as a separator modifier exhibits an enhanced electrochemical performance with a high average capacity of 955.64 mA h g^(-1) at 1C and a small capacity decay rate of 0.109%per cycle.Additionally,the density functional theory(DFT)calculation models have been rationally constructed and demonstrated that the doped S atoms in SMG possess higher binding energy to lithium polysulfides than that in MG,indicating that the SMG/PP separator can effectively capture soluble lithium polysulfides via chemical binding forces.This work would provide valuable insight into developing a versatile carbon-based separator modifier for LSB. 展开更多
关键词 Fluidized-bed chemical vapor deposition Mesoporous graphene s doping separator modification Lithium-sulfur battery
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Effects of reservoir fluids on sand packs consolidated by furan and epoxy resins:Static and dynamic states
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作者 Mohammad Nabi Tabbakhzadeh Feridun Esmaeilzadeh +1 位作者 Dariush Mowla Reza Zabihi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4504-4514,共11页
One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the flu... One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the fluids in the dynamic state have been assessed at the reservoir conditions.The analyses in this research were Young’s modulus,compressive strength,porosity,and permeability which were done on core samples after and before fluid contact.Samples made with two different resins showed good resistance to crude oil in both states.No considerable change was seen in the analyses even at high crude oil injection rates in the dynamic state.Conversely,brine caused a noticeable change in the analyses in both states.In the presence of brine at the static state,Young’s modulus and compressive strength respectively decreased by 37.5%and 34.5%for epoxy cores,whereas these parameters respectively reduced by 30%and 41%for furan cores.In brine presence at the dynamic state,compressive strength reduction was 10.28 MPa for furan and 6.28 MPa for epoxy samples and their compressive strength reached 16.75 MPa and 26.54 MPa respectively which are higher than the critical point to be known as weak sandstone core.Moreover,Young’s modulus decrease values for furan and epoxy samples were respectively 0.37 GPa and 0.44 GPa.Therefore,brine had a more destructive effect on the mechanical characteristics of samples in the static state than the dynamic one for two resins.In addition,brine injection increased permeability by about 13.6%for furan and 34.8%for epoxy.Also,porosity raised by about 21.8%for furan,and 19%for epoxy by brine injection.The results showed that the chemical sand consolidation weakens in the face of brine production along with crude oil which can lead to increasing cost of oil production and treating wellbore again. 展开更多
关键词 chemical sand consolidation Brine Flow rate static and dynamic states Crude oil Compressive strength Permeability Young’s modulus
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催化裂化原料变化对S Zorb装置结焦影响分析
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作者 刘洁 郭胜军 +1 位作者 李悦 雷梦莺 《炼油技术与工程》 CAS 2024年第10期4-7,共4页
催化裂化装置与其上下游装置关系密切,特别是对于单系列的炼油厂,上游装置工况的变化会对下游装置的生产运行产生重大影响。在渣油加氢装置换剂期间,催化裂化装置掺炼减压渣油,造成催化裂化原料性质严重恶化,原料中钒含量升高造成平衡... 催化裂化装置与其上下游装置关系密切,特别是对于单系列的炼油厂,上游装置工况的变化会对下游装置的生产运行产生重大影响。在渣油加氢装置换剂期间,催化裂化装置掺炼减压渣油,造成催化裂化原料性质严重恶化,原料中钒含量升高造成平衡剂活性下降,催化裂化汽油烯烃含量升高,导致S Zorb装置换热器E101快速结焦,影响S Zorb装置运行。因此,在渣油加氢装置换剂期间,建议提前采购低硫、低金属的轻质石蜡基原油,以减少催化裂化装置催化剂钒中毒情况的发生;尽量将催化裂化装置剂耗提至2.0 kg/t以上,以防平衡剂的钒含量过高;如果E101快速结焦且已经导致压力降过高,可通过化学清洗来清理E101管程中的焦。 展开更多
关键词 催化裂化装置 原料 s Zorb装置 结焦 汽油烯烃 化学清洗
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化学水浴沉积制备高质量Zn(O,S)薄膜及其性能研究
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作者 孙祺 赵颖 +3 位作者 李博研 陈静允 赵子铭 钟大龙 《太阳能学报》 EI CAS CSCD 北大核心 2024年第4期482-488,共7页
为获得铜铟镓硒薄膜太阳电池中高质量Zn(O,S)无镉缓冲层薄膜,该研究阐述了柠檬酸三钠作为络合剂制备Zn(O,S)薄膜的成膜机理,系统性研究了该体系下各反应参数对薄膜化学水浴沉积的影响。研究表明,柠檬酸三钠的浓度值显著影响反应类型,异... 为获得铜铟镓硒薄膜太阳电池中高质量Zn(O,S)无镉缓冲层薄膜,该研究阐述了柠檬酸三钠作为络合剂制备Zn(O,S)薄膜的成膜机理,系统性研究了该体系下各反应参数对薄膜化学水浴沉积的影响。研究表明,柠檬酸三钠的浓度值显著影响反应类型,异质反应更有利于生成高质量薄膜。同时,柠檬酸三钠与金属离子浓度的比值直接影响成膜质量和成膜速率,适合的pH溶液环境有助于提高Zn(O,S)薄膜沉积的质量。此外,通过工艺参数的优化,获得了电学性能接近传统CdS/CIGS太阳电池的Zn(O,S)/CIGS电池器件。 展开更多
关键词 薄膜太阳电池 缓冲层 络合 CIGs 柠檬酸三钠 Zn(O s) 化学水浴沉积
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基于B/S架构的智慧化工园区管理系统设计与实现
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作者 陈洋 王伟 《电脑与电信》 2024年第5期92-97,共6页
目前大部分化工园区内部基础设施“感知”程度、数字化、网络化程度较低,整体的安全生产监管信息化水平不高,管理者对庞大的企业、人员、事务和物资管控不足。对此,设计了基于B/S架构的智慧化工园区管理系统,应用数字技术和网络化手段... 目前大部分化工园区内部基础设施“感知”程度、数字化、网络化程度较低,整体的安全生产监管信息化水平不高,管理者对庞大的企业、人员、事务和物资管控不足。对此,设计了基于B/S架构的智慧化工园区管理系统,应用数字技术和网络化手段对传统化工园区进行改造和升级,建立园区和企业3D模型,融合物联网设备采集的数据信息,搭建园区数字孪生系统。提出平安指数算法规则,监测企业各项场景指标并对数据做风险评估,针对生产安全和指标异常问题,提出一套闭环的解决方案,实现化工园区安全的全方位管理。 展开更多
关键词 智慧化工园区 B/s架构 管理系统 数字孪生
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基于D-S证据理论的危化品水路运输风险模糊综合评价
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作者 吴蕊 程志友 《广州航海学院学报》 2024年第3期6-12,共7页
针对危险化学品水路运输风险因素的不确定性和模糊性,提出一种D-S证据理论与模糊综合评价法相结合的危化品水路安全运输风险评价方法。识别分析风险因素,建立危化品水路运输风险因素指标体系;引入距离函数,获取证据可信度后将可信度作... 针对危险化学品水路运输风险因素的不确定性和模糊性,提出一种D-S证据理论与模糊综合评价法相结合的危化品水路安全运输风险评价方法。识别分析风险因素,建立危化品水路运输风险因素指标体系;引入距离函数,获取证据可信度后将可信度作为专家权重,结合D-S证据理论,融合专家信息,合理分配指标权重;构建危化品水路运输风险模糊综合评价模型,对危化品水路运输风险等级进行评价。结果表明,该案例的量化风险值为37.389,隶属于较低风险等级,人员、管理、货物因素为关键影响因素,二级指标中教育培训不足、违规操作、安全意识不足、货物敏感条件、通航环境复杂风险值相对较高,需要进行重点防控。 展开更多
关键词 危化品水路运输 风险因素 D-s证据理论 指标权重 模糊综合评价
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Chemical Constituents of One Species of Endophytic Fungus in Taxus chinensis 被引量:3
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作者 张集慧 郭顺星 +1 位作者 杨峻山 肖培根 《Acta Botanica Sinica》 CSCD 2002年第10期1239-1242,共4页
Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on t... Three compounds were obtained from the mycelia of an endophytic fungus Gliocladium sp. (designated as strain F) of Taxus chinensis (Pilg.) Rehd. growing in Fujian Province, China. Their structures were determined on the basis of spectral analysis. (20S,22S)-4a-homo-22-hydroxy-4-oxaergosta-7,24(28)-dien-3-one was a novel compound. 4,8,12,16-tetramethyl-1,5,9,13-tetraoxacyclohexadecane-2,6,10,14-tetraone was firstly isolated from the genus ofGliocladium and 6,9-epoxyergosta-7,22-dien-3-ol was firstly obtained from the strain F. 展开更多
关键词 Taxus chinensis (20s 22s)-4a-homo-22-hydroxy-4-oxaergosta-7 24 (28)-dien-3-one chemical constituent Gliocladium sp.
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Chemical bonding and elastic properties of quaternary arsenide oxides YZnAsO and LaZnAsO investigated by first principles
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作者 施毅敏 叶绍龙 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1378-1382,共5页
The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized ... The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized gradient approximation (GGA). The GGA calculated structural parameters are in agreement with the experimental results. Population analysis suggests that the chemical bonding in YZnAsO and LaZnAsO can be classified as a mixture of ionic and covalent characteristic. Single-crystal elastic constants were calculated and the polycrystalline elastic modules were estimated according to Voigt, Reuss and Hill's approximations (VRH). The result shows that both YZnAsO and LaZnAsO are relatively soft materials exhibiting ductile behavior. The calculated polycrystalline elastic anisotropy result shows that LaZnAsO is more anisotropy in compressibility and YZnAsO is more anisotropy in shear. 展开更多
关键词 YZnAsO LaZnAsO chemical bonding elastic properties density-functional theory generalized gradientapproximation Voigt Reuss and Hill's approximations
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表面接枝C—S—H的岩沥青对高温油井水泥石力学性能的影响
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作者 王佳 张春梅 +2 位作者 张晔 程小伟 梅开元 《钻井液与完井液》 CAS 北大核心 2023年第6期806-814,共9页
研究了表面接枝C—S—H的岩沥青对高温油井水泥石力学性能和微观结构的影响,采用压力试验机及XRD、TG、SEM和EDS对油井水泥石的力学性能和微观结构进行了测试和表征。研究结果表明,与纯水泥石相比,掺入1%未改性岩沥青的水泥石3 d抗压强... 研究了表面接枝C—S—H的岩沥青对高温油井水泥石力学性能和微观结构的影响,采用压力试验机及XRD、TG、SEM和EDS对油井水泥石的力学性能和微观结构进行了测试和表征。研究结果表明,与纯水泥石相比,掺入1%未改性岩沥青的水泥石3 d抗压强度下降了2.98%,而掺入1%表面接枝C—S—H岩沥青的水泥石3 d抗压强度提高了4.26%。物相分析和热重实验表明,表面接枝C—S—H岩沥青的加入不会引起水化产物类型的变化,而掺量为3%表面接枝C—S—H的岩沥青水泥石养护3 d的失重量比纯水泥石高1.01%,说明表面接枝C—S—H的岩沥青可以促进水泥的水化。水泥石的微观形貌和元素分析表明,未改性岩沥青在180℃下热解导致沥青颗粒破碎,而接枝C—S—H的岩沥青表面形成的富Si层可以避免沥青颗粒因气孔而引起破碎,使得未改性岩沥青水泥石界面处的C元素含量较接枝C—S—H的岩沥青水泥石高29.14%,未改性岩沥青水泥石基体中C元素含量较接枝C—S—H的岩沥青水泥石高13.76%。 展开更多
关键词 岩沥青 C—s—H晶种 化学接枝 油井水泥 高温固井
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Recent advances in chemical adsorption and catalytic conversion materials for Li–S batteries 被引量:20
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作者 Xiaodong Hong Rui Wang +3 位作者 Yue Liu Jiawei Fu Ji Liang Shixue Dou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第3期144-168,共25页
Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercializat... Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercialization of Li–S batteries has been hindered by the insulation of sulfur,significant volume expansion,shuttling of dissolved lithium polysulfides(Li PSs),and more importantly,sluggish conversion of polysulfide intermediates.To overcome these problems,a state-of-the-art strategy is to use sulfur host materials that feature chemical adsorption and electrocatalytic capabilities for Li PS species.In this review,we comprehensively illustrate the latest progress on the rational design and controllable fabrication of materials with chemical adsorbing and binding capabilities for Li PSs and electrocatalytic activities that allow them to accelerate the conversion of Li PSs for Li–S batteries.Moreover,the current essential challenges encountered when designing these materials are summarized,and possible solutions are proposed.We hope that this review could provide some strategies and theoretical guidance for developing novel chemical anchoring and electrocatalytic materials for high-performance Li–S batteries. 展开更多
关键词 chemical adsorption ELECTROCATALYsIs Li–s BATTERIEs LITHIUM POLYsULFIDEs sHUTTLE effect
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Effects of reclaimed water irrigation and nitrogen fertilization on the chemical properties and microbial community of soil 被引量:11
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作者 GUO Wei Mathias N Andersen +4 位作者 QI Xue-bin LI Ping LI Zhong-yang FAN Xiang-yang ZHOU Yuan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第3期679-690,共12页
The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen(N)levels are important indicators of the effect... The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen(N)levels are important indicators of the effect of reclaimed water irrigation on environment.This study evaluated soil physicochemical properties and microbial community structure in soils irrigated with reclaimed water and receiving varied amounts of N fertilizer.The results indicated that the reclaimed water irrigation increased soil electrical conductivity(EC)and soil water content(SWC).The N treatment has highly significant effect on the ACE,Chao,Shannon(H)and Coverage indices.Based on a 16S ribosomal RNA(16S rRNA)sequence analysis,the Proteobacteria,Gemmatimonadetes and Bacteroidetes were more abundant in soil irrigated with reclaimed water than in soil irrigated with clean water.Stronger clustering of microbial communities using either clean or reclaimed water for irrigation indicated that the type of irrigation water may have a greater influence on the structure of soil microbial community than N fertilizer treatment.Based on a canonical correspondence analysis(CCA)between the species of soil microbes and the chemical properties of the soil,which indicated that nitrate N(NO3-–-N)and total phosphorus(TP)had significant impact on abundance of Verrucomicrobia and Gemmatimonadetes,meanwhile the p H and organic matter(OM)had impact on abundance of Firmicutes and Actinobacteria significantly.It was beneficial to the improvement of soil bacterial activity and fertility under 120 mg kg^-1 N with reclaimed water irrigation. 展开更多
关键词 reclaimed water NITROGEN soil chemical properties 16s rRNA sequence soil microbe community
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Leak Detection and Repair (LDAR) Standard Review for Self-Inspection and Management for VOC Emission in China’s Traditional Energy Chemical Industry 被引量:3
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作者 Jinbo Zhao Ming Chen 《Journal of Environmental Protection》 2018年第11期1155-1170,共16页
The emission of the traditional energy chemical industry accounts for 20% of the total manmade VOC emission in China, of which coal chemical and petrochemical plants are one of the most important VOC emission sources.... The emission of the traditional energy chemical industry accounts for 20% of the total manmade VOC emission in China, of which coal chemical and petrochemical plants are one of the most important VOC emission sources. VOC emission sources mainly include the leakage of oil refinery units and equipment, pipes and valves, respiration and leakage of various types of storage tanks, effusion of oils during loading and unloading, effusion of sewage treatment systems, all kinds of process tail gas, etc. In this paper, the current management status of VOC emission in China’s coal chemical industry and petrochemical industry are analyzed, which divides VOC management into intentional and fugitive emission. The Leak Detection and Repair (LDAR) management method and technology for equipment, pipes and valves implemented in the United States are studied to propose self-inspection management methods and measures for VOC emissions in the energy chemical industry, providing strategies and recommendations for energy conservation, emission reduction and cleaner production in the traditional energy chemical industry. 展开更多
关键词 sELF-INsPECTION VOC China’s TRADITIONAL Energy chemical INDUsTRY
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Interactions of chemical carcinogens and genetic variation in hepatocellular carcinoma 被引量:1
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作者 Yu-Jing Zhang 《World Journal of Hepatology》 CAS 2010年第3期94-102,共9页
In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts ... In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts with guanine in DNA and can lead to genetic changes. In HCC, the tumor suppressor gene p53 codon 249 mutation is associated with AFB 1 exposure and mutations in the K -ras oncogene are related to vinyl chloride exposure. Numerous genetic alterations accumulate during the process of hepatocarcinogenesis. Chemical carcinogen DNA-adduct formation is the basis for these genetic changes and also a molecular marker which reflects exposure level and biological effects. Metabolism of chemical carcinogens, including their activation and detoxification, also plays a key role in chemical hepatocarcinogenesis. Cytochrome p450 enzymes, N -acetyltransferases and glutathione S -transferases are involved in activating and detoxifying chemical carcinogens. These enzymes are polymorphic and genetic variation influences biological response to chemical carcinogens. This genetic variation has been postulated to influence the variability in risk for HCC observed both within and across populations. Ongoing studies seek to fully understand the mechanisms by which genetic variation in response to chemical carcinogens impacts on HCC risk. 展开更多
关键词 Hepatocellular carcinoma chemical CARCINOGENs AFLATOXIN B 1 POLYCYCLIC aromatic hydrocarbons 4-aminobiphenyl HEPATITIs B VIRUs HEPATITIs C VIRUs Glutathione s -transferase Cytochrome p450 enzymes Genetic variation
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S-N掺杂聚乙二醇用于锂硫电池的第一性原理研究
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作者 宋丽红 张敏刚 +2 位作者 曹翔宇 郭锦 闫晓燕 《材料导报》 EI CAS CSCD 北大核心 2023年第3期225-229,共5页
锂硫电池中可溶性多硫化物的穿梭效应严重限制了其产业化进程。聚乙二醇(PEG)作为正极和隔膜涂层在一定程度上可缓解穿梭。本工作采用基于密度泛函理论的第一性原理研究了S掺杂PEG400、N掺杂PEG400和S-N共掺杂PEG400对多硫化物的吸附机... 锂硫电池中可溶性多硫化物的穿梭效应严重限制了其产业化进程。聚乙二醇(PEG)作为正极和隔膜涂层在一定程度上可缓解穿梭。本工作采用基于密度泛函理论的第一性原理研究了S掺杂PEG400、N掺杂PEG400和S-N共掺杂PEG400对多硫化物的吸附机理,计算了吸附能、吸附最短距离、电荷转移和范德瓦尔斯力所占比例等。结果表明,三种基底对锂多硫化物均存在化学吸附作用,以N掺杂PEG400效果最佳。 展开更多
关键词 密度泛函理论 锂硫电池 化学吸附 涂覆材料 穿梭效应
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Topology Chemical Process Research on the Condensing and Growing Phase Multi Micro Oil Droplets Based on Hydrodynamics
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作者 周毅 李旋旗 +1 位作者 张东翔 TAPACOB B B 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期84-88,共5页
The hydrodynamic research about the droplet condensing of the multi phase liquid state on the surface of the coal glass and water discusses the deepening process of convex shape curve and the formation of S shape, and... The hydrodynamic research about the droplet condensing of the multi phase liquid state on the surface of the coal glass and water discusses the deepening process of convex shape curve and the formation of S shape, and puts emphasis on describing the diagram formation method of the later. In the induction period the active diagram of the micro droplet is decided by pH value forming as convex shape diagram or S shape diagram. When pH value is above 4.0, the damage of convex shape diagram cannot be recovered, in that case produce S shape activity diagram. When pH value is equal to or above 12.0, the hard surface with alkali liquid state loses adhesion, so that the micro droplet condensing of the multi phase liquid state stops completely. The research result shows that the water cleaning conditions of getting rid of the oil micro droplets can be decided by the pH value. 展开更多
关键词 growing of micro oil droplet condensing of micro oil droplet topology chemical process convexshape diagram s shape diagram
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Effects of Straw Returning and Chemical Control on Occurrence Quantity of Athetis lepigone Moschler in Summer Maize Fields
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作者 Lili LI Nan ZHAO +7 位作者 Jie SHI Ansheng ZHANG Xingyuan MEN Xianhong ZHOU Qianying ZHUANG Sicong ZHANG Zhenying WANG Yi YU 《Plant Diseases and Pests》 CAS 2012年第3期30-31,共2页
Athetis lepigone Moschler is a new kind of insect pest occurring in summer corn production areas. By investigation, it was found especially serious in straw returning fields. In this paper, its damage status was inves... Athetis lepigone Moschler is a new kind of insect pest occurring in summer corn production areas. By investigation, it was found especially serious in straw returning fields. In this paper, its damage status was investigated in straw returning and chemical controlled fields, respectively. The results showed that the rate of damaged plants was 82% and the maximum pest number per 100 plants was 88 heads in the straw returning fields without chemical control. The application of herbicides and pesticides had no significant effects on occurrence quantity and damage rate, but the pest number per 100 plants decreased a little compared to the fields without chemical control. In the surer er maize fields without straw returning, the application of herbicides and pesticides could significantly decrease the damage of Athetis lepigone, the rate of damaged plants was 20%, and the pest number per 100 plants was 6. 展开更多
关键词 summer maize straw returning Athet/s lepigone Moschler chemical control
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