检索结果-南通市图书馆

A new ent-labdane eiterpenoid lactone from Andrographis paniculata

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第3期20卷 317-319页

作者： Xiao Chi Ma Bao jing Zhang Sha Deng Shan Shan Huang Ke Xin Liu jing ming jia School of Pharmaceutical Sciences Dalian Medical University Dalian 116027 PR China School of Traditional Chinese Medicines Shenyang Pharmaceutical University Shengyang 110016 China

A new ent-labdane diterpenoid lactone with a new natural product was isolated from Andrographis paniculata. Their structures were elucidated on the basis of spectral evidences including 2D NMR.

关键词： Andrographis paniculata Ent-labdane diterpenoid Acanthaceae Lactone

ent-Pimarane Diterpenoid Dimers from Sigesbeckia glabrescens with Potent Anti-inflammatory Activities

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2021年第12期39卷 3315-3321页

作者： Xiao-Xu Gao Ying-Ying Zheng Xiao-Yu Zhang Gao-Sheng Hu jing-ming jia An-Hua Wang School of Traditional Chinese Materia Medica Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China

Chromatographic purification of Sigesbeckia glabrescens extracts led to three undescribed ent-pimarane diterpenoid dimers,named glabreside A—C(1-3).Their structures were confirmed by comprehensive spectroscopic analyses,and the structures of compound 1 and 3 were confirmed by X-ray *** results of anti-inflammatory activity assay showed that glabreside C(3)exhibited the most potent inhibition activity on nitric oxide(NO)production induced by lipopolysaccharide(LPS)in BV2 microglia compared with the other two *** C also increased the protein expression level of heme oxygenase-1(HO-1),and suppressed inducible nitric oxide synthase(iNOS)and cyclooxygenase 2(COX2)in LPS-stimulated BV2 ***,glabreside C exerts its anti-inflammatory effect by inhibiting AKT/MAPKs signaling *** findings indicate the vital role of ent-pimarane diterpenoid dimers in explaining the anti-inflammatory activity of *** and provide important evidence for further development and utilization of Sigesbeckiae *** results also suggest that glabreside C is a potential lead compound for anti-inflammatory drugs.

关键词： Siegesbeckia glabrescens Makino Terpenoids Biosynthesis Inflammatory Biological activity

Discovery of Highly Oxidized Abietane Diterpenoids from the Roots of Euphorbia fischeriana with Anti-tumor Activities

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 Chemistry 2021年第11期39卷 2973-2982页

作者： jiang-Chun Wei Yu-Ning Gao Dong-Dong Wang Xiao-Yu Zhang San-Peng Fan Te-Ri-Gen Bao Xiao-Xu Gao Gao-Sheng Hu An-Hua Wang jing-ming jia School of Traditional Chinese Materia Medica Shenyang Pharmaceutical UniversityShenyangLiaoning110016 China

Four previously undescribed ent-abietane diterpenoids(1—4),along with eleven known analogues(5—15),were isolated from the roots of wild Euphorbia *** gross structures were determined via extensive spectroscopic data,and the absolute configurations were elucidated by means of single-crystal X-ray diffraction analysis,Rh2(OCOCF3)4-induced CD spectrum and ECD *** cervical carcinoma inhibition activities counteract HeLa cells were screened by MTT assay,and the structure-activity relationships were further *** results demonstrated that 2(IC50 value at 3.75μmol/L)was more potent than *** underlying mechanism study revealed that 2 could distinctly induce apoptosis accompanied by increasing reactive oxygen species(ROS)production,Ca^(2+)influx and decreasing mitochondrial membrane ***,signal pathways including MAPKs/AKT might play a significant role in 2-induced cervical cancer cells death.

关键词： Euphorbia fischeriana Diterpenoids Structure elucidation Biological activity Anti-tumor

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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

Tungsten 2025年第1期7卷 120-136页

作者： Zao-ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang jia-jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： jing Lei Huijie Zhang jian Yang jia Ran Jiqiang Ning Haiyan Wang Yong Hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of Chemistry Zhejiang Normal University Jinhua Advanced Research Institute Department of Optical Science and Engineering Fudan University College of Chemistry and Materials Engineering Zhejiang A&F University

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF) has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA), but there still remain problems such as limited yield, short cycle life,and ambiguous reaction mechanism. Despite many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF, a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still lacking. We herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA, particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts, including heterointerface construction, defect engineering,single-atom engineering, and in situ reconstruction. Experimental characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated, and challenges and future directions of electrochemical oxidation of HMF are also prospected. This review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Structural design

Catalytic Performance of Carbon Smoke over Ag-LSCF Composite Catalysts

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 30-34页

作者： GUO Guanlun HAN ming LU Shaomin YU jing JU Hongling 无 Hubei Key Laboratory of Advanced Technology for Automotive Components&Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China College of Mechanical and Transportation Southwest Forestry UniversityKunming 650000China

To improve the catalytic performance of La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)(LSCF)towards carbon soot,we utilized the impregnation method to incorporate Ag into the prepared LSCF *** conducted a series of characterization tests and evaluated the soot catalytic activity of the composite catalyst by comparing it with the LaCoO_(3) group,LaFeO_(3) group,and catalyst-free *** results indicate that the Ag-LSCF composite catalyst exhibits the highest soot catalytic activity,with the characteristic temperature values of 376.3,431.1,and 473.9℃at 10%,50%,and 90%carbon soot conversion,*** values are 24.8,20.2,and 23.1℃lower than those of the LSCF *** also shows that LSCF can improve the catalytic activity of soot after compounding with Ag,and reflects the necessity of using catalysts in soot combustion *** characterization and BET test show that Ag-LSCF has more abundant surface-adsorbed oxygen species,larger specific surface area and pore volume than LSCF,which also proves that Ag-LSCF has higher soot catalytic activity.

关键词： metallic composites carbon smoke oxidation perovskite catalyst soot

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第2期17卷 548-565页

作者： ming‑Yuan Yu jing Wu Guang Yin Fan‑Zhen jiao Zhong‑Zhen Yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

基于可持续发展视角下我国资源型城市经济发展态势分析

在线全文

学校读者我要写书评

暂无评论

安全与环境学报 2023年第3期23卷 962-970页

作者：张国兴景明佳华北水利水电大学管理与经济学院郑州450046 华北水利水电大学黄河流域生态经济系统可持续发展研究中心郑州450046

资源型城市可持续发展是我国经济新常态建设的重要环节,为理清资源型城市转型过程中存在的问题和发展现状,基于CiteSpace软件,对CNKI总库中1991—2021年4436篇中文核心文献构建共现图谱,从发文机构、发文作者、研究内容3个角度深入研究... 详细信息

资源型城市可持续发展是我国经济新常态建设的重要环节,为理清资源型城市转型过程中存在的问题和发展现状,基于CiteSpace软件,对CNKI总库中1991—2021年4436篇中文核心文献构建共现图谱,从发文机构、发文作者、研究内容3个角度深入研究了我国资源型城市可持续发展态势。结果表明:我国相关高校(研究所)均对资源型城市的可持续发展转型态势开展了研究,发文机构集中于东北地区和西部地区,具有较强的区域性特征,且机构间合作处于较低水平。该领域核心作者数量众多,其中绝大多数偏向单独研究,作者间合作水平较低,未能形成固定合作团队。从关键词时间分布来看,该领域的研究内容以2004年、2014年为界可划分为3个阶段,由此产生的重要关键词节点有“经济转型”“产业转型”“城市转型”“循环经济”“低碳经济”。目前对资源型城市可持续发展转型态势的研究则更关注“新常态”和“耦合协调”。

关键词：环境科学技术基础学科资源型城市可持续发展 CiteSpace 科学知识图谱

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

我国煤矿领域安全经济研究态势分析

安全与环境学报 2021年第2期21卷 902-907页

作者：景明佳郭绍帅程磊华北水利水电大学财务处郑州450000 河南理工大学安全科学与工程学院河南焦作454000

为了了解我国煤矿安全经济领域的整体研究态势,基于中国知网(CNKI)文献数据,采用Cite Space V软件从研究机构、发文作者、热点关键词3个方面对我国煤矿安全经济领域的整体研究状况进行了汇总、分析。结果表明:在研究机构方面,大量的研... 详细信息

为了了解我国煤矿安全经济领域的整体研究态势,基于中国知网(CNKI)文献数据,采用Cite Space V软件从研究机构、发文作者、热点关键词3个方面对我国煤矿安全经济领域的整体研究状况进行了汇总、分析。结果表明:在研究机构方面,大量的研究机构在我国煤矿安全经济领域开展了研究,但各研究机构的发文量均处于比较低的水平,机构之间的合作关系较弱,在研究机构组成中,生产经营企业占据了较大的比例;在作者方面,作者之间的合作关系较弱,研究人员的发文量均处于比较低的水平;在热点关键词方面,我国在煤矿安全经济领域的研究态势处于不断发展变化中,2011—2015年研究热度达到最高,机电一体化是2016—2020年新增的主要研究热点。

关键词：安全社会工程煤矿经济中国知网(CNKI) CiteSpace