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The cardiovascular protective effect and mechanism of calycosin and its derivatives

Chinese Journal of Natural Medicines 2020年第12期18卷 907-915页

作者： PAN Li zhang xuan-fen WEI Wan-Sheng zhang Jing LI Zhen-Zhen Department of Cardiopulmonary Bypass Lanzhou University Second HospitalLanzhou 730000China Department of Orthopaedic Surgery Lanzhou University Second HospitalLanzhou 730000China

Cardiovascular disease is the main cause of mortality and morbidity in the world,especially in developing *** therapy is one of the main ways to treat cardiovascular *** them,great progress has been made in the treatment of cardiovascular diseases with traditional Chinese *** terms of experimental research,the mechanism of traditional Chinese medicine in the treatment of cardiovascular diseases has been thoroughly discussed in vitro and in *** terms of clinical treatment,traditional Chinese medicine with flavonoids,saponins and alkaloids as the main effective components has a definite effect on the treatment of cardiovascular diseases such as arrhythmia,myocardial ischemia,angina pectoris and myocardial infarction,with high safety and good application *** the further research on the effective ingredients,mechanism and adverse reactions of traditional Chinese medicine,it will be beneficial to the effectiveness of traditional Chinese medicine,reduce side effects and promote the modernization of traditional Chinese *** and its derivatives,the main bioactive flavonoids in Astragalus membranaceus have multiple biological effects,such as antioxidant,pro-angiogenesis,anti-tumour,and anti-inflammatory *** on the above biological effects,calycosin has been shown to have good potential for cardiovascular *** potent antioxidant effect of calycosin may play an important role in the cardiovascular protective *** injured cardiac myocytes,calycosin and its derivatives can alleviate the cell damage mainly marked by the release of myocardial enzymes and reduce the death level of cardiac myocytes mainly characterized by apoptosis through various *** vascular endothelial cells,calycosin also has multiple effects and multiple mechanisms,such as promoting vascular endothelial cell proliferation,exerting vasodilating effect and directly affecting the synthesis function of endothelial cel

关键词： Cardiovascular disease Calycosin Cadiac myocytes Vascular endothelial cells Protective effect

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Forecasting Fractures in Coal Seams by Using Azimuthal Anisotropy from P-Wave Seismic Data

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Journal of China University of Mining and Technology 2007年第1期17卷 11-14页

作者： DONG Shou-hua YUE Jian-hua zhang fen-xuan School of Resource and Earth Science China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Geophystcal Prospectmg Team Coal Geological Bureau of Shaanxi Province Xi＇an Shaanxi 710005 China

If the thickness of coal seams and the lithology of both roofs and floors of coal seams have not changed at all or only a little, then it is thought that the elastic anisotropy of coal seams depends mainly on fractures and obeys the horizontally symmetric model of an azimuth anisotropy. For a fixed offset, the amplitude A of the reflection P-wave and the cosine of 2φ has an approximately linear relation, (φ is the source-detector azimuth with respect to the fracture strike. Based on this relationship, many things can be done, such as the extraction of macro bins, the correction of residual normal moveout, the formation of azimuth gather, the transformation and normalization of azimuth gathers and the extraction of reflection wave amplitudes of coal seams. The least squares method was used to inverse theoretically the direction and density of fractures of coal seams. The result is in good agreement with the regional geological structure, indicating that the azimuth anisotropic analysis of the P-wave is feasible in evaluating the density and direction of fractures in coal seams.

关键词： coal fracture azimuth anisotropic analysis P-wave

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Recent progress in carbene-catalyzed fluoroalkylation

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Science China Chemistry 2024年第8期67卷 2448-2460页

作者： Bei zhang xuan zhang Jian Wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, which has attracted numerous scientists from different fields. This review focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past two decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents with various electronic characteristics, whether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lewis base catalysis, Umploung catalysis, radical catalysis and others. Meanwhile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis

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High-efficiently doping nitrogen in kapok fiber-derived hard carbon used as anode materials for boosting rate performance of sodium-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 472-482页

作者： Tianyun zhang Tian zhang Fujuan Wang fen Ran School of Mechanical and Electronical Engineering Lanzhou University of TechnologyLanzhou 730050GansuChina State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals School of Materials Science and EngineeringLanzhou University of TechnologyLanzhou 730500GansuChina

The engineering of plant-based precursor for nitrogen doping has become one of the most promising strategies to enhance rate capability of hard carbon materials for sodium-ion batteries;however,the poor rate performance is mainly caused by lack of pyridine nitrogen,which often tends to escape because of high temperature in preparation process of hard *** this paper,a high-rate kapok fiber-derived hard carbon is fabricated by cross-linking carboxyl group in 2,6-pyridinedicarboxylic acid with the exposed hydroxyl group on alkalized kapok with assistance of zinc ***,a high nitrogen doping content of 4.24%is achieved,most of which are pyridine nitrogen;this is crucial for improving the defect sites and electronic conductivity of hard *** optimized carbon with feature of high nitrogen content,abundant functional groups,degree of disorder,and large layer spacing exhibits high capacity of 401.7 mAh g^(−1)at a current density of 0.05 A g^(−1),and more importantly,good rate performance,for example,even at the current density of 2 A g^(−1),a specific capacity of 159.5 mAh g^(−1)can be *** findings make plant-based hard carbon a promising candidate for commercial application of sodium-ion batteries,achieving high-rate performance with the enhanced pre-cross-linking interaction between plant precursors and dopants to optimize aromatization process by auxiliary pyrolysis.

关键词： Kapok fiber Hard carbon Electrode materials Rate performance Sodium-ion batteries

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Recent Progress in Improving Rate Performance of Cellulose-Derived Carbon Materials for Sodium-Ion Batteries

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Nano-Micro Letters 2024年第8期16卷 102-147页

作者： Fujuan Wang Tianyun zhang Tian zhang Tianqi He fen Ran State Key Laboratory of Advanced Processing and Recycling of Non‑Ferrous Metals Lanzhou University of TechnologyLanzhou 730050People’s Republic of China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050People’s Republic of China School of Mechanical and Electronical Engineering Lanzhou University of TechnologyLanzhou 730050People’s Republic of China

Cellulose-derived carbon is regarded as one of the most promising candidates for high-performance anode materials in sodium-ion batteries;however,its poor rate performance at higher current density remains a challenge to achieve high power density sodium-ion *** present review comprehensively elucidates the structural characteristics of cellulose-based materials and cellulose-derived carbon materials,explores the limitations in enhancing rate performance arising from ion diffusion and electronic transfer at the level of cellulose-derived carbon materials,and proposes corresponding strategies to improve rate performance targeted at various precursors of cellulose-based *** review also presents an update on recent progress in cellulose-based materials and cellulose-derived carbon materials,with particular focuses on their molecular,crystalline,and aggregation ***,the relationship between storage sodium and rate performance the carbon materials is elucidated through theoretical calculations and characterization ***,future perspectives regarding challenges and opportunities in the research field of cellulose-derived carbon anodes are briefly highlighted.

关键词： Cellulose Hard carbon Anode materials Rate performance Sodium-ion batteries

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Optimising multi-vent module-based adaptive ventilation using a novel parameter for improved indoor air quality and health protection

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Building Simulation 2024年第1期17卷 113-130页

作者： Haotian zhang Xiaoxiao Ding Weirong zhang Weijia zhang Yingli xuan Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijing 100124China Department ofArchitecture TokyoPolytechnic UniversityTokyoJapan

As infectious respiratory diseases are highly transmissible through the air,researchers have improved traditional total volume air distribution systems to reduce infection ***-vent module-based adaptive ventilation(MAV)is a novel ventilation type that facilitates the switching of inlets and outlets to suit different indoor scenarios without changing ductwork ***,little research has evaluated MAV module sizing and air velocity selection,both related to MAV system efficiency in removing contaminants and the corresponding level of protection for occupants in the ventilated ***,the module-source offset ratio(MSOR)is proposed,based on the MAV module size and its distance from an infected occupant,to inform selection of optimal MAV module *** fluid dynamics simulations illustrated contaminant distribution in a two-person MAV equipped *** phase particles modelled respiratory contaminants from the infected occupant,and contaminant concentration distributions were compared under four MAV air distribution layouts,three air velocities,and three module sizes considered using the *** indicate that lower air velocities favour rising contaminant levels,provided the ventilation rate is *** contaminant discharge can be achieved when the line of outlets is located directly above the infected *** this parameter to guide MAV system design,85.7% of contaminants may be rendered harmless to the human body within 120 s using the default air vent layout.A more appropriate supply air velocity and air vent layout increases this value to 91.4%.These results are expected to inform the deployment of MAV systems to reduce airborne infection risk.

关键词： multi-vent module-based adaptive ventilation computational fluid dynamics indoor air quality infection control

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Influence of ecological function protection zone on the water conservation in Gansu-Qinghai Contiguous Region of the upper Yellow River

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Journal of Mountain Science 2024年第4期21卷 1345-1357页

作者： TONG Huali CHEN Qingbo zhang xuan College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Gansu Province Land Use and Comprehensive Improvement Engineering Research Center Lanzhou 730070China

The implementation of Ecological Function Protection Zone(EFPZ)policy is significant for the ecological restoration and conservation of soil and water in the territory *** manuscript analyzed and quantified the impact of EFPZ on the regional water conservation function,based on land use data from 2005,2008,2010,2015 and 2020,by conducting a counterfactual simulation along with the GeoSOS-FLUS model and the InVEST *** results demonstrate that the delineation of EFPZ can significantly influence the water conservation.(1)From 2010 to 2020,as the EFPZ was implemented,the water conservation in the study area was increasing year by year,with a growth rate of 0.03×10^(8) m^(3)∙a^(-1).On the other hand,the simulated water conservation capacity without the implementation of EFPZ decreased year by year,with a decrease rate of 0.01×10^(8) m^(3)∙a^(-1).(2)The EFPZ accounts for only 23%of the total area,but the contribution rate of water conservation reaches 80%.The actual values of water conservation and average water yield per unit pixel in the EFPZ show an increasing trend both internally and externally,while the counterfactual simulation values exhibit a decreasing trend.(3)The water conservation is much higher within the EFPZ than without *** implementation of EFPZ has a significant effect on the improvement of the water conservation capacity in Maqu EFPZ and Yellow River Source *** protection effectiveness should be enhanced in Qilian Mountain EFPZ and afforestation activities need to be carefully considered in Loess Plateau EFPZ.

关键词： Water conservation function Ecological Function Protection Zone Counterfactual simulation Geo SOS-FLUS model InVEST model

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Endochondral ossification of hindlimbs in embryonic development of Japanese Quail(Coturnix japonica)

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Avian Research 2024年第1期15卷 123-132页

作者： xuan Li Yuxin zhang Hongfeng Zhao College of Life Sciences Shaanxi Normal UniversityXi’an710119China

The endochondral ossification of hindlimb is essential to a bird’s ability to stand,walk and *** hindlimb is ossified in the embryos before hatching in precocial ***,the molecular mechanisms of hindlimb ossification in birds is still ***,we tried to examine the process of hindlimb ossification and its molecular regulation by using an animal model—Japanese Quail(Coturnix japonica).We selected four critical stages(Embryo Day:E6,E8,E12 and E16) of skeletal development of embryonic quails for hindlimb skeleton staining to show the process of endochondral ossification and to examine the molecular regulation of endochondral osteogenesis by RNA-Seq *** results showed that ossification became increased with embryonic development and most hindlimb was ossified before ***-Seq analysis revealed that various signaling pathways were involved with endochondral ossification with thyroid hormone signaling and WNT signaling pathway particularly ***,the expression levels of 42 genes were continuously upregulated and 14 genes were continuously downregulated from E6 to *** present study might provide new insights into complex molecular mechanisms in regulation of endochondral ossification.

关键词： Embryos Hindlimb Ossification Precocial Transcriptomics

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Design and tailoring of patterned ZnO nanostructures for perovskite light absorption modulation

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 855-861页

作者： Haonan Si xuan Zhao Qingliang Liao Yue zhang Academy for Advanced Interdisciplinary Science and Technology Beijing Advanced Innovation Center for Materials Genome EngineeringUniversity of Science and Technology BeijingBeijing 100083China Key Laboratory of Advanced Materials and Devices for Post-Moore Chips Ministry of EducationBeijing Key Laboratory for Advanced Energy Materials and TechnologiesSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Lithography is a pivotal micro/nanomanufacturing technique,facilitating performance enhancements in an extensive array of devices,encompassing sensors,transistors,and photovoltaic *** key to creating highly precise,multiscale-distributed patterned structures is the precise control of the lithography ***,high-quality patterned ZnO nanostructures are constructed by systematically tuning the exposure and development times during *** optimizing these parameters,ZnO nanorod arrays with line/hole arrangements are successfully *** ZnO nanostructures with highly controllable morphology and structure possess discrete three-dimensional space structure,enlarged surface area,and improved light capture ability,which achieve highly efficient energy conversion in perovskite solar *** lithography process management for these patterned ZnO nanostructures provides important guidance for the design and construction of complex nanostructures and devices with excellent performance.

关键词： lithography patterned ZnO nanorod arrays light absorption perovskite solar cell

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Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG xuan zhang Hualao WANG Bridge and Tunnel Research Center Research Institute of Highway Ministry of TransportBeijing 100088China Tunnel and Underground Engineering Research Center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service *** aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single *** used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track ***,the numerical method was verified by comparing the results of numerical simulation and on-site ***,the characteristics of aerodynamic pressure were ***,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was *** results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel *** addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel *** pressure amplitude in the two-train case is higher than that for a single *** maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage *** P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage *** P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

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