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Fingerprinting Analysis of Saposhnikovia divaricata using ~1H Nuclear Magnetic Resonance Spectroscopy and High Performance Liquid Chromatography

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Journal of Integrative Plant Biology 2010年第9期52卷 782-792页

作者： Yue-Yang Xin An-Jun Deng Guan-Hua Du jin-Lan zhang hai-Lin Qin Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education & Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

The 1H nuclear magnetic resonance （1H NMR） fingerprints of fractionated non-polar and polar extracts （control substance for plant drug [CSPD] A and B） from the roots of 12 specimens of Saposhnikovia divaricata （Turcz.） Schischk were achieved with Fourier Transform （FT）-NMR spectrometer and assigned by comparison to each other and to the 1H NMR spectra of the isolated individual compounds. These fingerprints were found to be uniform in terms of the specificity for the implication of all 12 specimens being systematically of the same origin. The uniformity was further affirmed by high performance liquid chromatography （HPLC）, which also revealed exactly identical specificity for the identified S. divaricata species with the 1H NMR appearances of corresponding CSPD on the part of the composition of characteristic constituents when comparing to corresponding individual compounds. This investigation unambiguously shows that the specific signals from the chemotaxonomically significant compounds of chromones and coumarins in S. divaricata are exhibited distinctively in the composite features of both 1H NMR fingerprints and HPLC profiles. The 1H NMR and HPLC profiles established can successfully be used as reference for the authentication of the origin of S. divaricata species as well as for chemotaxonomic studies.

关键词： FINGERPRINTS NUCLEAR magnetic resonance spectroscopy HIGH performance liquid chromatography COUMARINS CHEMOTAXONOMY

Dual template-induced construction of three-dimensional porous SiO2/NC/Co-CNTs heterostructure with highly dispersed active sites for efficient oxygen evolution reaction

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Tungsten 2024年第3期6卷 585-595页

作者： hai-Qi zhang Xiao-Jun Zeng Qing-Qing zhang Zu-Liang zhang Chu-Long jin Rong-hai Yu School of Materials Science and Engineering Jingdezhen Ceramic University School of Materials Science and Engineering Beihang University

The development and exploration of efficient and economical electrocatalysts for oxygen evolution reaction（OER） represents the main bottleneck to unlocking a sustainable energy scenario based on elec trocataly tic water *** scale integration of three-dimensional（3D） porous heterostructure with highly dispersed active sites and good structural stability is ***,a dual template route is developed to construct the 3D porous SiO2/nitrogen-doped carbon（NC）/Co-carbon nano tubes（CNTs） hetero ***,the hard template（SiO2nano spheres） contributes to 3D porous structure,increases the specific surface area,and promotes the contact area of the *** the same time,the soft template（basic zinc carbonate） can control the growth of 1D CNTs and facilitate the exposure of the active ***,3D porous SiO2/NC/Co-CNTs hetero structure inherits highly dispersed Co nanoparticles coated by *** conductive channels and abundant N hetero atoms doping are reasonably constructed by a dual template ***,SiO2/NC/Co-CNTs catalyst provides an extraordinary activity for the OER in alkaline media,with a low overpotential of 298 mV at a current density of 10 mA·***,SiO2/NC/Co-CNTs hetero structure enables excellent long-term durability with a 10 mV decay in overpotential after 3000 cyclic voltammetry cycles,and 97% remain in current density over 20 *** is believed that this dual template strategy can provide a new and simple way to construct a highly dispersed active site in electrocatalysts.

关键词： Dual template High dispersion Porous heterostructure Conductive channels Oxygen evolution reaction

Answering reachability queries with ordered label constraints over labeled graphs

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Frontiers of Computer Science 2024年第1期18卷 105-117页

作者： Daoliang HE Pingpeng YUAN hai jin National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science&TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Reachability query plays a vital role in many graph analysis *** researches proposed many methods to efficiently answer reachability queries between vertex *** many real graphs are labeled graph,it highly demands Label-Constrained Reachability(LCR)query inwhich constraint includes a set of labels besides vertex *** researches proposed several methods for answering some LCR queries which require appearance of some labels specified in constraints in the *** that constraint may be a label set,query constraint may be ordered labels,namely OLCR(Ordered-Label-Constrained Reachability)queries which retrieve paths matching a sequence of ***,no solutions are available for ***,we propose DHL,a novel bloom filter based indexing technique for answering OLCR *** can be used to check reachability between vertex *** the answers are not no,then constrained DFS is ***,we employ DHL followed by performing constrained DFS to answer OLCR *** show that DHL has a bounded false positive rate,and it's powerful in saving indexing time and *** experiments on 10 real-life graphs and 12 synthetic graphs demonstrate that DHL achieves about 4.8-22.5 times smaller index space and 4.6-114 times less index construction time than two state-of-art techniques for LCR queries,while achieving comparable query response *** results also show that our algorithm can answer OLCR queries effectively.

关键词： graph ordered-label-constrained reachability partial index bloom filter query processing

Existence of a-Cores for Games Without Compact Assumptions

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Journal of the Operations Research Society of China 2024年第2期12卷 520-527页

作者： hai-Qun zhang School of International Economics and Trade Shanghai Lixin University of Accounting and Fin Shanghai201209China

Following the representation of Kajii(J Econ Theory 56:194-205,1992),we provide some existence theorems ofα-cores for games without ordered preferences and compact *** applications,we obtain some existence results of... 详细信息

关键词： α-Core Existence Preference Noncompactness

A systematic review of the inequality of health burdens related to climate change

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 137-153页

作者： Xinke Song Shihui zhang hai Huang Qun Ding Fang Guo Yaxin zhang jin Li Mingyu Li Wenjia Cai Can Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Department of Earth System Science Tsinghua UniversityBeijing100084China

Climate change significantly impacts human health,exacerbating existing health inequalities and creating new *** study addresses the lack of systematic review in this area by analyzing 2440 publications,focusing on four key terms:health,disparities,environmental factors,and climate *** inclusion criteria limited the selection to English-language,peer-reviewed articles related to climate health hazards,ensuring the relevance and rigor of the synthesized *** process synthesized 65 relevant *** investigation revealed that recent research,predominantly from developed countries,has broadened its scope beyond temperature-related impacts to encompass diverse climate hazards,including droughts,extreme weather,floods,mental health issues,and the intersecting effects of Coronavirus Disease *** has highlighted exposure as the most studied element in the causal chain of climate change-related health inequalities,followed by adaptive capability and inherent *** most significant vulnerabilities were observed among populations with low socioeconomic status,ethnic minorities,and *** study further reveals research biases and methodological limitations,such as the paucity of attention to underdeveloped regions,a narrow focus on non-temperature-related hazards,challenges in attributing climate change effects,and a deficit of large-scale empirical *** findings call for more innovative research approaches and a holistic integration of physical,socio-political,and economic dimensions to enrich climate-health discourse and inform equitable policy-making.

关键词： Climate change Health impact Human well-being Inequality Vulnerability

Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang jin-Dong zhang Dong-Ting Gao Gang Liu Chun-hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

Effect of microalloying on wettability and interface characteristics of Zr-based bulk metallic glasses with W substrate

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China Foundry 2024年第4期21卷 352-359页

作者： Zhen zhang Lin-na Feng jin-he Wang Zheng-kun Li Hua-meng Fu Hong Li Zheng-wang Zhu hai-feng zhang School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Northeastern UniversityShenyang 110004China

The infiltration casting method is widely employed for the preparation of ex-situ composite ***,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming *** experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs ***,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

关键词： Zr-based BMGs infiltration casting method wettability interface characteristics W-Zr phases

Development of lithium-free P2-type high-sodium content cathode materials with enhanced cycle and air stability for sodium-ion batteries

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Rare Metals 2024年第1期43卷 113-123页

作者： jin-Lv Tian Lin-Rong Wu hai-Jun Zhao Shou-Dong Xu Liang Chen Ding zhang Xiao-Chuan Duan College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Chemistry Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430205China

The effect of partial substitution of Mg for Ni on a high-sodium and lithium-free layered P2-type Na_(45/54)Mg_(6)/_(54)Ni_(12/54)Mn_(34/54)O_(2) cathode with high initial Coulombic efficiency and excellent cyclic stability has been investigated in this *** on the crystal structural analysis,the Mg doping can retain the P2 structure up to 4.3 V,thus restraining the detrimental phase transformation of P2-02during the Na-ion intercalation/deintercalation ***,the obtained Mg-doped P2-type cathode exhibits a reversible specific capacity of 109 mAh·g^(-1) at 0.1C between 2.0 and 4.3 V and a retention rate of 81.5% after 200cycles at *** addition,the full cell consisting of Mg-doped P2-type cathode and hard carbon anode shows a capacity retention rate of 85.6% after 100 *** study provides new insight into the development of durable cathode materials for sodium-ion batteries.

关键词： Sodium-ion batteries Cathode material High sodium content Air stability

A hybrid memory architecture supporting fine-grained data migration

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Frontiers of Computer Science 2024年第2期18卷 31-41页

作者： Ye CHI Jianhui YUE Xiaofei LIAO haikun LIU hai jin National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Department of Computer Science Michigan Technological UniversityMichigan 49931USA

Hybrid memory systems composed of dynamic random access memory(DRAM)and Non-volatile memory(NVM)often exploit page migration technologies to fully take the advantages of different memory *** previous proposals usually migrate data at a granularity of 4 KB pages,and thus waste memory bandwidth and DRAM *** this paper,we propose Mocha,a non-hierarchical architecture that organizes DRAM and NVM in a flat address space physically,but manages them in a cache/memory *** the commercial NVM device-Intel Optane DC Persistent Memory Modules(DCPMM)actually access the physical media at a granularity of 256 bytes(an Optane block),we manage the DRAM cache at the 256-byte size to adapt to this feature of *** design not only enables fine-grained data migration and management for the DRAM cache,but also avoids write amplification for Intel Optane *** also create an Indirect Address Cache(IAC)in Hybrid Memory Controller(HMC)and propose a reverse address mapping table in the DRAM to speed up address translation and cache ***,we exploit a utility-based caching mechanism to filter cold blocks in the NVM,and further improve the efficiency of the DRAM *** implement Mocha in an architectural *** results show that Mocha can improve application performance by 8.2%on average(up to 24.6%),reduce 6.9%energy consumption and 25.9%data migration traffic on average,compared with a typical hybrid memory architecture-HSCC.

关键词： non-volatile memory hybrid memory system data migration fine-grained caching