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A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1171-1188页

作者： wei wei Feng guan Xin FANG College of Intelligent Science National University of Defense TechnologyChangsha410073China Naval Research Academy Beijing100161China

A metamaterial vibration isolator,termed as wave-insulating isolator,is proposed,which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave *** consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and *** bandgap mechanisms,vibration isolation properties,effects of key parameters,and robustness to complex conditions are *** experimentally demonstrated,the wave-insulating isolator can improve the vibration insulation in the ranges of[50 Hz,180 Hz]and[260 Hz,400 Hz]by 15 dB and 25 dB,respectively,in contrast to the conventional isolator with the same first resonant frequency.

关键词： metamaterial and metastructure vibration isolation bandgap wave insulation plate

Effect of Alpinia officinarum Hance alcohol extracts on primary dysmenorrheal

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Asian Pacific Journal of Tropical Medicine 2016年第9期9卷 861-865页

作者： Ling Huang Jun-Qing Zhang You-Bin Li Mi Liu Hui-Ming Deng Yu-Chao Luo Yin-Feng Tan Jie Hou Gui-wei Yao wei-wei guan School of Pharmaceutical Sciences Hainan Medical University

Objective:To study the effect of Alpinia officinarum Hance(***) 80% alcohol extract on the primary ***:*** 80% alcohol extract were enriched by macroporous adsorption *** mice of primary dysmenorrhea model were established by oxytocin induction; the effects of *** 80% alcohol extract on primary dysmenorrhea were observed by body twist method; and the homogenate level of prostaglandin F_(2α)(PGF_(2α)),prostaglandin E_2(PGE_2) and Ca^(2+) in the uterus were observed in oxytocin-induced female ***:The writhing frequency of primary dysmenorrhea mice was significantly decreased after treatment of *** 80% alcohol extract and the level of PGF_(2α),PGE_2 and Ca^(2+) in mice uterus was significantly decreased(P<0.05,P<0.01) in groups of mice treated with middle and high dosage of *** 80% alcohol extract compared with that of model ***:These findings suggest that *** 80% alcohol extract can significantly relieve primary dysmenorrhea.

关键词： Alpinia officinarum Hance alcohol extracts Relieve Primary dysmenorrhea

Construction of metallo-complexes with 2,2′:6′,2″-terpyridine substituted triphenylamine in different modified positions and their photophysical properties

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Chinese Chemical Letters 2024年第7期35卷 301-305页

作者： Shengwen guan Zhaotong wei Ningxu Han Yude wei Bin Xu Ming Wang Junjuan Shi State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The stable coordinated metallo-complexes based on 2,2′:6′,2″-terpyridine(tpy)and its derivatives have been widely researched for various wide-ranging applications in photoelectronics,catalysis,sensor,photoluminescence,and so ***,the most reported studies ignored the comprehensive comparison between structures modified by different positions and ***,we design a series of metallo-complexes which were assembled with tpy substituted triphenylamine(TPA)at different positions and metal ions and explored their photophysical *** the solution state,MLE_(2)based on the 5,5″-positions modification showed the highest PLQYs and PL *** the increase of solvent polarity,MLB2exhibit the largest *** the solid state,from MLA_(2)to MLE_(2),the emission colours are gradually red-shifted from yellow to *** findings in this work may pave a new way to design functional metallo-complexes,not just for PL properties.

关键词： Metallo-complexes 2,2′:6′,2″-terpyridine Triphenylamine Different modified positions Photophysical properties

A review on Bi_(2)WO_(6)-based photocatalysts synthesis, modification, and applications in environmental remediation, life medical, and clean energy

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 87-108页

作者： wei Mao Xuewu Shen Lixun Zhang Yang Liu Zehao Liu Yuntao guan guangdong Provincial Engineering Technology Research Center for Urban Water Cycle and Water Environment Safety Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China State Environmental Protection Key Laboratory of Microorganism Application and Risk Control School of EnvironmentTsinghua UniversityBeijing 100084China

Photocatalysis has emerged a promising strategy to remedy the current energy and environmental crisis due to its ability to directiy convert clean solar energy into chemical *** tungstate(Bi_(2)WO_(6))has been shown to be an excellent visible light response,a well-defined perovskite crystal structure,and an abundance of oxygen atoms(providing efficient channels for photogenerated carrier transfer)due to their suitable band gap,effective electron migration and separation,making them ideal *** has been extensively applied as photocatalyst in aspects including pollutant removal,carbon dioxide reduction,solar hydrogen production,ammonia synthesis by nitrogen photocatalytic reduction,and cancer *** this review,the fabrication and application of Bi_(2)WO_(6) in photocatalysis were comprehensively *** photocatalytic properties of BizwO-based materials were significantly enhanced by carbon modification,the construction of heterojunctions,and the atom doping to improve the photogenerated carrier migration rate,the number of surface active sites,and the photoexcitation ability of the *** addition,the potential development directions and the existing challenges to improve the photocatalytic performance of Bi_(2)WO_(6)-based materials were discussed.

关键词： Bismuth tungstate Synthesis and modification Photocatalytic application Environmental remediation Clean energy Medical science

Quality assessment of friction-stir-welded aluminum alloy welds via three-dimensional force signals

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Advances in Manufacturing 2024年第1期12卷 61-75页

作者： Ji-Hong Dong Yi-Ming Huang Jia-Lei Zhu wei guan Xu-Kai Ren Huan-wei Yu Lei Cui Beijing Institute of Petrochemical Technology Beijing102617People’s Republic of China Beijing Academy of Safety Engineering and Technology Beijing102617People’s Republic of China AVIC Manufacturing Technology Institute Beijing100024People’s Republic of China Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin300350People’s Republic of China Shaoxing Special Equipment Testing Institute Shaoxing Key Laboratory of Special Equipment Intelligent Testing and EvaluationShaoxing312071ZhejiangPeople’s Republic of China

An online detection technology must be developed for realizing the real-time control of friction stir *** this study,the three-dimensional force exerted on a material during friction stir welding was collected synchronously and the relationship between the forces and welding quality was *** results indicated that the fluctuation period of the traverse force was equal to that of the lateral force during the stable welding *** phase difference between two horizontal forces wasπ/*** values of the horizontal forces increased with welding speed,whereas their amplitudes remained the *** proposed force model showed that the traverse and lateral forces conformed to an elliptical curve,and this result was consistent with the behavior of the measured *** variational mode decomposition was used to process the plunge *** intrinsic mode function that represented the real fluctuation in the plunge force varied at the same frequency as the spindle rotational *** tunnel defects occurred,the fluctuation period features were consistent with those obtained during normal welding,whereas the ratio parameter defined in this study increased significantly.

关键词： Friction stir welding(FSW) Three-dimensional force model Variational mode decomposition Tunnel defect

Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 791-805页

作者： Xu Zeng Tao Yang Jian-wei Feng Cong-Sheng Bian Ming guan wei Liu Bing-Cheng Guo Jin Dong Research Institute of Petroleum Exploration and Development China National Petroleum CorporationBeijing100083China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China School of Earth Sciences China University of PetroleumQingdao266400ShandongChina

Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in th

关键词： Fractures Development characteristics Controlling factors Shale oil Sweet spot

A novel structure of ultra-high-loading small moleculesencapsulated ZIF-8 colloid particles

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Nano Research 2024年第4期17卷 2929-2940页

作者： Pengfei Duan Yunhe An Xiaoxiao wei Yanjie Tian Di guan Xiangwen Liu Lanqun Mao Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100089China College of Chemistry Beijing Normal UniversityBeijing 100875China

The safety of nanoparticle-based drug delivery systems(DDSs)for cancer treatment is still a challenge,restricted by the intrinsic cytotoxicity of drug carriers and leakage of loaded ***,we propose a novel nanocarrier’s cytotoxicity avoidance strategy by synthesizing an encapsulation core–shell structure of zeolitic imidazolate framework-8(ZIF-8)-based colloid particles(CPs)with an amorphous ZIF-8 *** encapsulation structure achieves an ultra-high loading rate(LR)of 90%(i.e.,9 mg doxorubicin(DOX)per 1 mg ZIF-8)for DOX and the protection of DOX from ***,to deliver unit-dose drug,this ultra-high LR of 90%significantly reduces the usage of ZIF-8 to 1.2%(2 orders of magnitude)compared to that of DOX@ZIF-8 with a 10%LR,in which cytotoxicity of ZIF-8 could well below the safety limit and then be relatively ***,drug delivery efficacy,scale-up ability,and universality of this encapsulation structure have been further *** findings suggest the great potential of this ZIF-8-based encapsulation core–shell structure in the field of drug delivery.

关键词： metal-organic frameworks zeolitic imidazolate framework-8(ZIF-8) drug delivery nanoparticles nanostructures

Beam based alignment using a neural network

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Nuclear Science and Techniques 2024年第4期35卷 108-118页

作者： guan-Liang Wang Ke-Min Chen Si-wei Wang Zhe Wang Tao He Masahito Hosaka guang-Yao Feng wei Xu National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Diamond Light Source Oxfordshire OX110DEUK

Beams typically do not travel through the magnet centers because of errors in storage *** beam deviating from the quadrupole centers is affected by additional dipole fields due to magnetic field ***-based alignment(BBA)is often performed to determine a golden orbit where the beam circulates around the quadrupole center *** storage rings with many quadrupoles,the conventional BBA procedure is time-consuming,particularly in the commissioning phase,because of the necessary iterative *** addition,the conventional BBA method can be affected by strong coupling and the nonlinearity of the storage ring *** this study,a novel method based on a neural network was proposed to determine the golden orbit in a much shorter time with reasonable *** golden orbit can be used directly for operation or adopted as a starting point for conventional *** method was demonstrated in the HLS-II storage ring for the first time through simulations and online *** results of the experiments showed that the golden orbit obtained using this new method was consistent with that obtained using the conventional *** development of this new method and the corresponding experiments are reported in this paper.

关键词： Golden orbit Beam-based alignment Neural network Storage ring

Research Progress and Challenges on Persistent Organic Pollutants in Lakes

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Journal of Earth Science 2024年第2期35卷 729-736页

作者： wei Guo Xiaoyu Ji Zhengfei Yu Hongchen Jiang Xiangyu guan School of Ocean Sciences China University of GeosciencesBeijing 100083China State Key Lab of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

Lakes are the main reservoirs of persistent organic pollutants(POPs)from land,atmo sphere and *** in lakes undergo complex exchange,transformation,and degradation between water-air-sediment-biota interfaces,which are constrained and regulated by various physical,chemical and biological *** can affect ecological conditions,chemical properties of water and sedi ments,and biodiversity of the lake ***,it is important to study the sources,migration,transformation,environmental behavior and ecological impacts of POPs in lake *** re view summarizes research progress on detection technologies,diversity and origins,historical records,migration and transformation,distribution patterns,degradation and toxic effects of POPs in *** nally,future directions related to POPs in lakes were summarized.

关键词： persistent organic pollutants(POPs) lakes transformation degradation microbes environment geolgogy