检索结果-南通市图书馆

Studies on glucosyloxybenzyl succinate derivatives from the pseudobulbs of Pleione bulbocodioides

在线全文

学校读者我要写书评

暂无评论

Studies on glucosyloxybenzyl succinate derivatives from the ...

Modelling the formation and dissolution behavior of alumina agglomerate in the cryolite

中国化学会第十二届全国天然有机化学学术会议

作者： Shaowei Han Chao Wang Baosong Cui Hua Sun jianjun Zhang Shuai li State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical College

Ten previously undescribed glucosyloxybenzyl succinate derivatives,pleionosides A-J（1-10）,and fifteen known compounds（11-25） were isolated from the pseudobulbs of Pleione bulbocodioides（Franch.） *** structures were elucidated by a combination of MS and NMR data,physical and chemical methods and a comparison with known ***,three compounds exhibited potent hepatoprotective activity against N-acetyl-p-aminophenol（APAP）-induced HepG2 cell damage in in vitro assays,with cell survival rates of31.89%,31.52% and 31.97% at 10 μ*** compounds exhibited moderate antioxidant activity with increasing viability at 10μM of 36.1%,45.0 %,25.5% and 20.7%.

关键词： Pleione bulbocodioides Orchidaceae Glucosyloxybenzyl succinate derivatives Hepatoprotective activity Antioxidant activity

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Particuology 2024年第3期86卷 211-222页

作者： Jiaqi Wang Mao li Benjun Cheng Hesong li School of Energy Science and Engineering Central South UniversityChangsha410083China

The presence of alumina agglomerates seriously affects the current efficiency of the aluminum electrolysis *** the dynamic dissolution process of agglomerates is essential to improve the current efficiency of aluminum electrolysis.A mathematical model is proposed to describe the different phenomena from the formation until complete dissolution of *** permeation and solidification processes of cryolite,a semi-analytical mathematical model is developed to formulate the formation,melting and dissolution processes of agglomerates,and the time duration for each stage is *** and heat mass transfer of agglomerates are explored based on the packing theory and mechanism of heat mass transfer in wet porous *** approach is applied to investigate the main factors affecting the dissolution stages and porosity of *** results show that the superheat has a great influence on the formation and melting stage,the diameter of agglomerates can reach 14.93 mm for 200 particles *** density decreases with the increase of agglomerated particle number,which varies in the range of 2.27-2.28 g/cm^(3).The average dissolution rate of agglomerates is about 1.83×10^(-5)-2.95×10^(-5) kg/s within the range of alumina concentration in this study.

关键词： Mathematical model Alumina agglomerate Porous media Packing theory Heatand mass transfer

A review: Enhanced recovery of natural gas hydrate reservoirs

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2019年第9期27卷 2062-2073页

作者： Fengguang li Qing Yuan Tianduo li Zhi li Changyu Sun Guangjin Chen Shandong Provincial Key Laboratory of Molecular Engineering Qilu University of Technology(Shandong Academy of Science)Jinan 250653China School of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng 252059China State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249China

Natural gas hydrate(NGH)is a highly efficient and clean energy,with huge reserves and widespread distribution in permafrost and marine *** all over the world are committed to developing an effective exploring technology for NGH *** this paper,four conventional in-situ hydrate production methods,such as depressurization,thermal stimulation,inhibitor injection and CO2 replacement,are briefly *** to the limitations of each method,there has been no significantly breakthrough in hydrate exploring *** by the development of unconventional oil and gas fields,researchers have put forward some new hydrate production *** summarize the enhanced hydrate exploiting methods,such as CO2/N2–CH4 replacement,CO2/H2–CH4 replacement,hydraulic fracturing treatment,and solid exploration;and potential hydrate mining techniques,such as self-generating heat fluid injection,geothermal stimulation,the well pattern optimization of hydrate *** importance of reservoir stimulation technology for hydrate exploitation is emphasized,and it is believed that hydrate reservoir modification technology is a key to open hydrate resources exploitation,and the major challenges in the process of hydrate exploitation are pointed *** combination of multiple hydrate exploring technologies and their complementary advantages will be the development trend in the future so as to promote the process of hydrate industrialization.

关键词： Hydrate Exploration/exploitation Recovery Production Stimulation technology

Tribological study of two ammonium chloride-decanoic acid deep eutectic solvents(DESs)as high-performance lubricants

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第11期12卷 2441-2457页

作者： Zhuocheng li Enhui ZHANG Weimin li Haichao liU State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Zibo Innovation Center of High-End Synthetic Lubricating Materials Zibo 255000China

Deep eutectic solvents(DESs)are acknowledged as a novel class of functional *** share similar physical properties with ionic liquids(ILs)and have the potential to be a novel class of *** this study,two DESs,namely tetrabutylammonium chloride-decanoic acid DES(C4-DES)and methyl tricaprylmethylammonium chloride-decanoic acid DES(C8-DES),were synthesized,and their physico-chemical properties and tribological performances were ***-analysis of the rubbing surfaces used multiple techniques to gain insights into the lubrication *** show that the coefficient of friction(COF)and wear were reduced by approximately 29%and 91%for the C4-DES,and 36%and 94%for the C8-DES,compared to an ester base *** friction reduction behavior of the DESs is attributed to the monolayer adsorption of the polar group in the decanoic acid(DEAC),whose effectiveness is affected by the component of the ammonium salts in the DESs and the operating *** addition to the adsorbed film,worn surface analysis revealed that an ultra-thin tribochemical film with a thickness of 3–7 nm was formed on the surfaces lubricated with the *** composition of the film was studied,and the lubrication mechanisms of the two DESs were discussed.

关键词： deep eutectic solvent(DES) lubricants tribological performance boundary lubrication

Magic of hydrogen spillover: Understanding and application

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Green Energy & Environment 2022年第6期7卷 1161-1198页

作者： Haifang Shen Hao li Zhensheng Yang Chunli li National-Local Joint Engineering Laboratory for Energy Conservation in Chemical Process Integration and Resources Utilization Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of Technology8 Guangrong RoadTianjin300130China

The hydrogen spillover effect(HSPE)plays an important role in heterogeneous catalysis and hydrogen storage as an interfacial phenomenon,which facilitates the improvement of hydrogen storage properties of porous nanomaterials and indirectly or directly affects the reaction performance of multiphase catalytic *** setting-up of the word“hydrogen spillover”opened up a new area to gain insight into the dynamic behavior of migrating hydrogen atoms on a catalyst ***,a comprehensive understanding of the HSPE is still ***,the development of advanced characterization techniques provides increasingly valuable information to further our understanding of the *** on these considerations,in this review,we hope to provide some answers to the question“What is hydrogen spillover and how do we recognize it?”.To do this,we will rely on advanced characterization techniques as well as experimental and theoretical ***,we discuss in detail the influences of the HSPE on hydrogen storage performance and the important catalytic effects of the HSPE in *** effects will be reviewed by looking through the catalytic results obtained in many reactions in thermal catalysis,electrocatalysis,and ***,based on the application potential of hydrogen spillover,we present some preliminary research proposals and discuss the opportunities and challenges that remain to be faced in this research area.

关键词： Hydrogen spillover Characterization Hydrogen storage Catalysis Spillover mechanism

Variations in the Microstructure and Properties of Mn-Ti Multiple-phase Steel with High Strength under Different Tempering Temperatures

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2015年第2期28卷 430-436页

作者： li Dazhao li Xiaonan CUI Tianxie li Jianmin WANG Yutian FU Peimao School of Materials Scinece and Engineering North University of China Technology Center Taiyuan Iron & Steel (Group) Co. School of Materials Scinece and Engineering Tianjin University

There are few relevant researches on coils by tempering,and the variations of microstructure and properties of steel coil during the tempering process also remain *** using thermo-mechanical control process（TMCP）technology,Mn-Ti typical HSLA steel coils with yield strength of 920 MPa are produced on the 2250 hot rolling production ***,the samples are taken from the coils and tempered at the temperatures of 220℃,350℃,and 620℃*** tempering the strength,ductility and toughness of samples are tested,and meanwhile microstructures are *** initially emerge inside the ferrite laths and the density of the dislocation ***,the lath-shaped ferrites begin to gather,and the retained austenite films start to ***,the retained austenite films are completely decomposed into coarse and short rod-shape precipitates composed of C and Ti *** yield strength increases with increasing tempering temperature due to the pinning effect of the precipitates,and the dislocation density *** yield strength is highest when the steel is tempered at 220℃because of pinning of the precipitates to *** total elongation increases in all samples because of the development of ferrites during *** tensile strength and impact absorbed energy decline because the effect of impeding crack propagation weakens as the retained austenite films completely decompose and the precipitates *** paper clarifies the influence of different tempering temperatures on phase transformation characteristics and process of Mn-Ti typical multiphase steels,as well as its resulting performance variation rules.

关键词： multiple-phase microstructure lath-shaped ferrite polygonal ferrite precipitate retained austenite film

Profiling interfacial reaction features between diamond and Cu-Sn-Ti active filler metal brazed at 1223 K

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第36期131卷 100-105页

作者： Yonggang Fan Kenan li Haodong li Cong Wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) School of MetallurgyNortheastern UniversityShenyang 110819China State Key Laboratory of Superabrasives Zhengzhou Research Institute for Abrasives&Grinding Co.Ltd.Zhengzhou 450001China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Diamond/Cu-Sn-Ti composites have been successfully prepared by cold-press forming in conjunction with high-temperature vacuum active brazing at 1223 *** wetting behaviors between diamond and filler metal,interfacial characteristics of the reaction layer,and wear resistance of the bulky composite have been fully *** is revealed that all diamond particles can only be fully coated when the TiH_(2)content exceeds 5 wt%,below which sharp edges on diamond can still be *** interfacial reaction layer is found to be composed of TiC,the thickness of which is demonstrated to increase as a function of TiH_(2)content,arriving at the peak value of 1.70μm and remaining almost constant *** is further shown that the maximum wear resistance occurs approaching 5 wt%TiH_(2)*** mechanisms responsible for such interesting phenomena have been postulated.

关键词： Diamond Cu-Sn-Ti Brazing Interfacial layer Powder metallurgy

Tsunami hazard assessment in the South China Sea:A review of recent progress and research gaps

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2022年第5期65卷 783-809页

作者： linlin li Qiang QIU Zhigang li Peizhen ZHANG Guangdong Provincial Key Laboratory of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyInnovation Academy of South China Sea Ecology and Environmental EngineeringChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China China-Pakistan Joint Research Center on Earth Sciences CAS-HECIslamabad 45320Pakistan

The South China Sea region is potentially threatened by tsunami hazards originated from multiple sources:the Manila subduction zone in the east,the littoral Fault Zone(LFZ)in the north,numerous submarine landslides on the continental slopes and the volcanic islands in the Luzon *** but potentially devastating tsunami hazard poses a great threat to the populous coastal region,fishery,oil and gas exploitation in the deep sea,*** we review the recent progress in tsunami hazard assessment in the South China Sea region,focusing on two primary sources:submarine earthquakes and *** sort and review the literature by the two commonly used approaches:deterministic and probabilistic tsunami hazard assessment for both source *** simulating tsunamis generated by typical earthquakes originated from the Manila Trench,the LFZ and landslides in the continental slopes,we investigate their tsunamigenic mechanism and key tsunami characteristics in the South China Sea *** point out the research gaps and highlight the key issues to be addressed in the future.

关键词： Tsunami Submarine earthquake Submarine landslide the littoral Fault Zone

The Al_(2)O_(3)and Mn/Al_(2)O_(3)sorbents highly utilized in destructive sorption of NF_(3)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第1期65卷 54-62页

作者： Yanfei Pan Hejian li li Zheng Xiufeng Xu School of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China

NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse ***,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse *** the technologies for NF_(3)abatement,the destructive sorption of NF_(3)over metal oxides sorbents is an effective ***,the search for a highly reactive and utilized sorbent for NF_(3)destruction is in great *** this work,AlOOH supported on carbon-sphere(AlOOH/CS)as precursors were synthesized hydrothermally and heat-treated to prepare the Al_(2)O_(3)*** influence of AlOOH/CS hydrothermal temperatures on the reactivity of derived Al_(2)O_(3)sorbents for NF_(3)destruction was investigated,and it is shown that the Al2O3 from AlOOH/CS hydro-thermalized at 120℃is superior to ***,the optimized Al_(2)O_(3)was covered by Mn(OH)x to prepare Mn/Al_(2)O_(3)sorbents via changing hydrothermal temperatures and Mn *** results show that the Mn/Al_(2)O_(3)sorbents are more utilized than bare Al_(2)O_(3)in NF_(3)destructive sorption due to the promotional effect of Mn_(2)O_(3)as surface layer on the fluorination of Al_(2)O_(3)as substrate,especially the optimal 5%Mn/Al2O3(160℃)exhibits a utilization percentage as high as 90.4%,and remarkably exceeds all the sorbents reported so *** findings are beneficial to develop more efficient sorbents for the destruction of NF_(3).

关键词： Greenhouse gas NF_(3)destructive sorption Sorbents Al_(2)O_(3) Mn/Al_(2)O_(3) Reactivity