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Rare Metals 2011年第1期30卷 49-52页

作者： LI Liangfeng qiu Tai YANG Jian FENG Yongbao State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials Southwest University of Science and Technology Mianyang 621010 China College of Materials Science and Engineering Nanjing University of Technology Nanjing 210009 China

To obtain novel intermediate temperature alloy solders with a melting temperature of 400-600°C,nominal（Ag-Cu28）-30Sn alloys without or with a trace addition（0.5 or 1.0 wt.%） of rare earth（RE） element La were prepared by mechanical *** aim of this research is to investigate the effects of the addition of La on the microstructures,alloying process and melting properties of（Ag-Cu28）-30Sn *** results show that the addition of La produces no new phase.A trace amount of La addition can effectively refine the grain size,but the excessive addition of 1.0 wt.% La inhibits the alloying *** influence of La on the melting temperatures of solder alloys is ***,the trace addition of 0.5 wt.% La can distinctly reduce the fusion zone and improve the melting property of（Ag-Cu28）-30Sn alloys.

关键词： solders rare earths mechanical alloying microstructure melting

Synthesis and modification strategies of g-C_(3)N_(4) nanosheets for photocatalytic applications

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Advanced Powder Materials

Advanced Powder Materials 2024年第1期3卷 49-79页

作者： Long Chen Michael A.Maigbay Miao Li Xiaoqing qiu College of Chemistry and Chemical Engineering Central South UniversityChangshaChina

Graphitic carbon nitride nanosheets(CNNs)become the most promising member in the carbon nitride family benefitted from their two-dimensional structural ***,great endeavors have been made in the synthesis and modification of CNNs to improve their photocatalytic properties,and many exciting progresses have been *** order to elucidate the fundamentals of CNNs based catalysts and provide the insights into rational design of photocatalysis system,we describe recent progress made in CNNs preparation strategies and their applications in this ***,the physicochemical properties of CNNs are briefly ***,the synthesis approaches of CNNs are reviewed,including top-down stripping strategies(thermal,gas,liquid,and composite stripping)and bottom-up precursor molecules design strategies(solvothermal,template,and supramolecular self-assembly method).Subsequently,the modification strategies based on CNNs in recent years are discussed,including crystal structure design,doping,surface functionalization,constructing 2D heterojunction,and anchoring *** the multifunctional applications of g-C_(3)N_(4) nanosheet based materials in photocatalysis including H_(2) evolution,O_(2) evolution,overall water splitting,H_(2)O_(2) production,CO_(2) reduction,N_(2) fixation,pollutant removal,organic synthesis,and sensing are ***,the opportunities and challenges for the development of high-performance CNNs photocatalytic systems are also prospected.

关键词： G-C_(3)N_(4) Nanosheets Synthesis strategies Modified strategies Photocatalytic applications

Effects of MgO promoter on properties of Ni/Al_(2)O_(3) catalysts for partial oxidation of methane to syngas

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Frontiers of Chemical Science and Engineering 2007年第2期1卷 167-171页

作者： qiu Yejun CHEN Jixiang ZHANG Jiyan Department of Catalysis Science and Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The effects of MgO promoter on the physico-chemical properties and catalytic performance of Ni/Al_(2)O_(3) catalysts for the partial oxidation of methane to syngas were studied by means of BET,XRD,H2-TPR,TEM and perfor-mance *** was found that the MgO promoter bene-fited from the uniformity of nickel species in the catalysts,inhibited the formation of NiAl2O4 spinel and improved the interaction between nickel species and *** results were related to the formation of NiO–MgO solid solution and MgAl_(2)O_(4) ***,for the catalysts with a proper amount of MgO promoter,the nickel dispersiveness was enhanced,therefore making their catalytic performance in methane partial oxidation ***,the excessive MgO promoter exerted a negative effect on the catalytic ***,the basicity of MgO promoted the reversed water–gas shift reaction,which led to an increase in CO selectivity and a decrease in H2 *** suitable content of MgO promoter in Ni/Al_(2)O_(3) catalyst was∼7 wt-%.

关键词： Ni/Al2O3 catalyst magnesium oxide partial oxidation of methane syngas

Local quantum Fisher information and quantum correlation in the mixed-spin Heisenberg XXZ chain

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Frontiers of physics 2024年第2期19卷 235-245页

作者： Peng-Fei Wei Qi Luo Huang-qiu-Chen Wang Shao-Jie Xiong Bo Liu Zhe Sun School of Physics Hangzhou Normal UniversityHangzhou 310036China Zhejiang Institute of Modern Physics and School of Physics Zhejiang UniversityHangzhou 310027China School of Information and Electrical Engineering Hangzhou City UniversityHangzhou 310015China Zhejiang Provincial Key Laboratory of Urban Wetlands and Regional Change Hangzhou 311121China

We study the local quantum Fisher information(LQFI)in the mixed-spin Heisenberg XXZ *** the maximal and minimal LQFI are studied and the former is essential to determine the accuracy of the quantum parameter estimation,the latter can be well used to characterize the discord-type quantum *** investigate the effects of the temperature and the anisotropy parameter on the maximal LQFI and thus on the accuracy of the parameter *** we make use of the minimal LQFI to study the discord-type correlations of different site *** dimensions of the subsystems cause different values of the minimal LQFI which reflects the asymmetry of the discord-type *** addition,the site pairs at different positions of the spin chains have different minimal LQFI,which reveals the influence of the surrounding spins on the bipartite quantum *** results show that the LQFI obtained through a simple calculation process provides a convenient way to investigate the discord-type correlation in high-dimensional systems.

关键词： local quantum Fisher information quantum correlation mixed-spin Heisenberg XXZ chain

Crustal S-wave velocity structure across the northeastern South China Sea continental margin: implications for lithology and mantle exhumation

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Earth and Planetary Physics 2019年第4期3卷 314-329页

作者： WenAi Hou Chun-Feng Li XiaoLi Wan MingHui Zhao XueLin qiu Institute of Marine Geology and Resources Zhejiang University Zhoushan Zhejiang 316021 China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The northeastern margin of the South China Sea (SCS), developed from continental rifting and breakup, is usually thought of as a non-volcanic margin. However, post-spreading volcanism is massive and lower crustal high-velocity anomalies are widespread, which complicate the nature of the margin here. To better understand crustal seismic velocities, lithology, and geophysical properties, we present an S-wave velocity (VS) model and a VP/VS model for the northeastern margin by using an existing P-wave velocity (VP) model as the starting model for 2-D kinematic S-wave forward ray tracing. The Mesozoic sedimentary sequence has lower VP/VS ratios than the Cenozoic sequence;in between is a main interface of P-S conversion. Two isolated high-velocity zones (HVZ) are found in the lower crust of the continental slope, showing S-wave velocities of 4.0–4.2 km/s and VP/VS ratios of 1.73–1.78. These values indicate a mafic composition, most likely of amphibolite facies. Also, a VP/VS versus VP plot indicates a magnesium-rich gabbro facies from post-spreading mantle melting at temperatures higher than normal. A third high-velocity zone (VP : 7.0–7.8 km/s;VP/VS: 1.85–1.96), 70-km wide and 4-km thick in the continent-ocean transition zone, is most likely to be a consequence of serpentinization of upwelled upper mantle. Seismic velocity structures and also gravity anomalies indicate that mantle upwelling/ serpentinization could be the most severe in the northeasternmost continent-ocean boundary of the SCS. Empirical relationships between seismic velocity and degree of serpentinization suggest that serpentinite content decreases with depth, from 43% in the lower crust to 37% into the mantle.

关键词： South China Sea continental margin crustal structure converted S-wave VP/VS ratio lithology serpentinization

Phytochemistry and pharmacology of genus Ephedra

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Chinese Journal of Natural Medicines 2018年第11期16卷 811-828页

作者： ZHANG Ben-Mei WANG Zhi-Bin XIN Ping WANG qiu-Hong BU He KUANG Hai-Xue Key Laboratory of Chinese Materia Medica (Ministry of Education) Heilongjiang University of Chinese Medicine Department of Natural Medicinal Chemistry College of Pharmacy Guangdong Pharmaceutical University

The genus Ephedra of the Ephedraceae family contains more than 60 species of nonflowering seed plants distributed throughout Asia, America, Europe, and North Africa. These Ephedra species have medicinal, ecological, and economic value. This review aims to summarize the chemical constituents and pharmacological activities of the Ephedra species to unveil opportunities for future research. Comprehensive information on the Ephedra species was collected by electronic search(e.g., GoogleScholar, Pubmed, Sci Finder, and Web of Science) and phytochemical books. The chemical compounds isolated from the Ephedra species include alkaloids, flavonoids, tannins, polysaccharides, and others. The in vitro and in vivo pharmacological studies on the crude extracts, fractions and few isolated compounds of Ephedra species showed anti-inflammatory, anticancer, antibacterial, antioxidant, hepatoprotective, anti-obesity, antiviral, and diuretic activities. After chemical and pharmacological profiling, current research is focused on the antibacterial and antifungal effects of the phenolic acid compounds, the immunosuppressive activity of the polysaccharides, and the antitumor activity of flavonoids.

关键词： Ephedra Phytochemistry Pharmacology

Black-hole-inspired thermal trapping with graded heat-conduction metadevices

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National Science Review 2023年第2期10卷 131-138页

作者： Liujun Xu Jinrong Liu Peng Jin Guoqiang Xu Jiaxin Li Xiaoping Ouyang Ying Li Cheng-Wei qiu Jiping Huang Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (MOE) Fudan University Department of Electrical and Computer Engineering National University of Singapore Graduate School of China Academy of Engineering Physics School of Materials Science and Engineering Xiangtan University Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical InstrumentationZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang University International Joint Innovation Center Key Laboratory of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang The Electromagnetics Academy of Zhejiang University Zhejiang University

The curved space-time produced by black holes leads to the intriguing trapping *** far,metadevices have enabled analogous black holes to trap light or sound in laboratory ***,trapping heat in a conductive environment is still challenging because diffusive behaviors are *** by black holes,we construct graded heat-conduction metadevices to achieve thermal trapping,resorting to the imitated advection produced by graded thermal conductivities rather than the trivial solution of using insulation materials to confine thermal *** experimentally demonstrate thermal trapping for guiding hot spots to diffuse towards the *** heat-conduction metadevices have advantages in energy-efficient thermal regulation because the imitated advection has a similar temperature field effect to the realistic advection that is usually driven by external energy *** results also provide an insight into correlating transformation thermotics with other disciplines,such as cosmology,for emerging heat control schemes.

关键词： thermal trapping graded metadevices imitated advection

一种新型微空阴极结构的大气压射频冷等离子体源

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物理学报 2006年第11期55卷 5872-5877页

作者：裘亮孟月东任兆杏钟少锋中国科学院等离子体物理研究所合肥230031

介绍微空阴极的结构和物理机理,着重介绍一种新型大气压下射频激励的大面积冷等离子体源---融合空心阴极(fused hollow cathodes,FHC).结合应用和与之有关的研究,简单介绍空心阴极的放电特性,以及影响其放电特性的因素,如阴极材料、气... 详细信息

介绍微空阴极的结构和物理机理,着重介绍一种新型大气压下射频激励的大面积冷等离子体源---融合空心阴极(fused hollow cathodes,FHC).结合应用和与之有关的研究,简单介绍空心阴极的放电特性,以及影响其放电特性的因素,如阴极材料、气体种类、频率、气体流速、气压、阴极内径等.另外提到了其他两种相关的微空阴极系统.

关键词：微空阴极大气压冷等离子体射频

Herb-drug interaction in the protective effect of Alpinia officinarum against gastric injury induced by indomethacin based on pharmacokinetic, tissue distribution and excretion studies in rats

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Journal of Pharmaceutical Analysis 2021年第2期11卷 200-209页

作者： Xuguang Zhang Zhenrui Xie Xun Chen Junqiang qiu Yinfeng Tan Xiaoliang Li Hailong Li Junqing Zhang Key Laboratory of Tropical Translation Medicine of Ministry of Education Hainan Provincial Key Laboratory for Research and Development of Tropical HerbsSchool of PharmacyHainan Medical UniversityHaikou571199China

Alpinia officinarum Hance of the Chinese traditional herb for the treatment of emesis, abdominal pain and diarrhea has been used to counteract gastric disease induced by indomethacin in rats without obvious side effects. However, the role of herb-drug interaction between indomethacin and A. officinarum based on pharmacokinetic, tissue distribution and excretion still remains unknown. In this study, an ultra-fast liquid-tandem mass spectrometry(UFLC-MS/MS) method was developed for simultaneous determination of indomethacin and its three metabolites, O-desmethylindomethacin(ODI), deschlorobenzoylindomethacin(NDI) and indomethacin acyl-b-D-glucuronide(IDAbG) by oral administration of indomethacin solution with and without the ethanolic extract of A. officinarum and applied to comparative pharmacokinetic, tissue distribution and excretion studies. Our results clarified that oral administration of A. officinarum produced significant alterations in the pharmacokinetic parameters of indomethacin. And the pharmacokinetic interaction between indomethacin and A. officinarum reduced the systemic exposure of indomethacin and increased its elimination. Tissue distribution results demonstrated that co-administration of A. Officinarum could not reduce the accumulation of indomethacin in the target tissue of the stomach, but could accelerate the excretions of indomethacin and its three metabolites including ODI, NDI and IDAb G in the bile and feces of rats in the excretion ***, A. Officinarum might have a gastrointestinal protective effect through the interaction role with indomethacin based on the pharmacokinetics and excretion in rats.

关键词： Alpinia officinarum Hance Indomethacin Herb-drug interaction Pharmacokinetics Tissue distribution Excretion

A Bifunctional-Blocker-Aided Hybridization Chain Reaction Lighting-Up Self-calibrating Nanocluster Fluorescence for Reliable Nucleic Acid Detection

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Journal of Analysis and Testing 2024年第2期8卷 160-169页

作者： Dan Zhang Guobao Zhou Hongyan Yang Yi Wang Lijun Shen Yuxuan qiu Lei Li Longhua Guo College of Chemistry and Materials Science Zhejiang Normal UniversityJinhua321004China Jiaxing Key Laboratory of Molecular Recognition and Sensing College of BiologicalChemical Sciences and EngineeringJiaxing UniversityJiaxing314001China College of Life Sciences and Medicine Zhejiang Sci-Tech UniversityHangzhou314000China

In this work,we proposed a ratiometric silver nanoclusters(AgNCs)fluorescent assay by designing a bifunctional-blockeraided hybridization chain reaction(HCR).Hairpin probe 1(HP1)containing two special DNA fragments(5′-CAC CGC T-3′and 5′-ATT TGC CTT TTG GGG ACG GATA-3′)at two terminals creates a red-emitting AgNC nucleation sequence(rNS,5′-CAC CGC TAT TTG CCT TTT GGG GAC GGATA-3′).We found that the presence of a toehold fragment(5′-TGCCC-3′)in HP1 could silence the *** the addition of a target nucleic acid,HCR of HP1 and hairpin probe 2(HP2)could be initiated,resulting in the formation of long chain of DNA duplexes with multibranched *** the toehold fragment in HP1participated in generating duplexes,a strong emission of rNS-templated AgNCs was observed at 670 *** significantly,a bifunctional blocker was introduced not only to reduce the background red-emitting fluorescence but also to play as an internal green-emitting AgNCs nucleation *** the one hand,the blocker could increase the signal-to-noise-ratio of the constructed biosensor,and on the other hand,the blocker also helped to prepare ratiometric HCR-AgNCs assay with self-calibrating ability to strengthen its *** with the traditional HCR-AgNCs sensors,the developed ratiometric assay based on the bifunctional-blocker-aided HCR has higher reliability,which is important for the fabrication of biosensors in various fields for practical biosensing applications.

关键词： Ratiometric fluorescence Hybridization chain reaction Silver nanocluster Biosensor Bifunctional blocker