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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 673-681页

作者：丁庆军 ZHOU Changsheng 张高展 guo Hong LI Yang ZHANG Yongyuan guo Kaizheng School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Advanced Building Materials Key Laboratory of Anhui Province School of Material Science and Chemical EngineeringAnhui Jianzhu UniversityHefei 230601China China Railway 17th Bureau Group Co. Ltd.Taiyuan 030006China

We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for *** properties of compressive strength,elastic modulus,ultrasonic pulse velocity,flexural strength,and toughness were *** electron microscopy and nanoindentation were also conducted to reveal the underlying mechanisms affecting macroscopic *** to the superior interface bonding properties between mullite sand and matrix,the compressive strength and flexural toughness of UHPC have been significantly *** sand and BCS aggregates have higher stiffness than quartz sand,contributing to the excellent elastic modulus exhibited by *** stiffness and volume of aggregates have a more significant impact on the elastic modulus of UHPC than interface performance,and the latter contributes more to the strength of *** study will provide a reference for developing UHPC with superior elastic modulus for structural engineering.

关键词： ultra-high performance concrete mechanical properties fine aggregates microstructure nanoindentation

The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar Basin,NW China

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Petroleum Science 2024年第2期21卷 836-854页

作者： Mao-guo Hou Ming Zha Hua Liu Hai-Lei Liu Jiang-Xiu Qu Ablimit Imin Xiu-Jian ding Zhong-Fa Jiang School of Geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and Development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The Fengcheng formation

Natural vibration and critical velocity of translating Timoshenko beam with non-homogeneous boundaries

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1523-1538页

作者： Yanan LI Jieyu ding Hu ding Liqun CHEN Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai Frontier Science Center of MechanoinformaticsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mathematics and Statistics Qingdao UniversityQingdao 266071Shandong ProvinceChina

In most practical engineering applications,the translating belt wraps around two fixed *** boundary conditions of the dynamic model are typically specified as simply supported or fixed *** this paper,non-homogeneous boundaries are introduced by the support *** the translating belt as the mechanical prototype,the vibration characteristics of translating Timoshenko beam models with nonhomogeneous boundaries are investigated for the first *** governing equations of Timoshenko beam are deduced by employing the generalized Hamilton's *** effects of parameters such as the radius of wheel and the length of belt on vibration characteristics including the equilibrium deformations,critical velocities,natural frequencies,and modes,are numerically calculated and *** numerical results indicate that the beam experiences deformation characterized by varying curvatures near the *** radii of the wheels play a pivotal role in determining the change in trend of the relative difference between two beam *** the results unearths that the relative difference in equilibrium deformations between the two beam models is more pronounced with smaller-sized *** the two wheels are of equal size,the critical velocities of both beam models reach their respective *** addition,the relative difference in natural frequencies between the two beam models exhibits nonlinear variation and can easily exceed 50%.Furthermore,as the axial velocities increase,the impact of non-homogeneous boundaries on modal shape of translating beam becomes more *** dealing with non-homogeneous boundaries is challenging,beam models with non-homogeneous boundaries are more sensitive to parameters,and the differences between the two types of beams undergo some interesting variations under the influence of non-homogeneous boundaries.

关键词： translating beam Timoshenko beam non-homogeneous boundary natural frequency critical velocity

Honeycomb-like MoCo alloy on 3D nitrogen-doped porous graphene for efficient hydrogen evolution reaction

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Rare Metals 2024年第3期43卷 1072-1082页

作者： Lin-Ping Wang Kuang Li Hua-Long ding Le Xu Chen Huang Jiao-Jiao Zhou Cong-TaoWen Pei-Lin Zhang wei-wei Wang Lu-Yang Chen Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China State Key Laboratory of High-Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai200050China State Key Laboratory of Chemical Engineering and School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai200237China

An efficient electrocatalyst is indispensable to significantly reduce energy consumption and accelerate the conversion efficiency of water *** this work,the honeycomb-like porous MoCo alloy on nitrogen-doped three-dimensional(3D)porous graphene substrate(Mo_(0.3)Co_(0.7)@NPG)has been synthesized from the annealing of layered double hydroxide(MoCo-LDH@NPG).Especially,the Mo_(0.3)Co_(0.7)@NPG exhibits low hydrogen evolution overpotential of 75 mV(10 mA·cm^(-2))and a Tafel slope of 69.9 mV·dec^(-1),which can be attributed to highly conductive NPG substrate,the unique nanostructure and the synergistic effect of Mo and ***,the Mo_(0.3)Co_(0.7)@NPG can maintain the original morphology and high catalytic activity after 50-h stability *** work proposes a general strategy to synthesize a multi-element alloy on conductive substrates with high porosity for electrocatalytic reaction.

关键词： MoCo alloy Three-dimensional nitrogen-doped porous graphene Hydrogen evolution reaction(HER)

Design of high frequency broadband low insertion loss SAW filter at 3.5 GHz

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 55-61页

作者： Wang wei Zhang Ying Wang Fang Wu Hao ding Hui Xia Xu Wang Guanyu Xie Yingtao School of Optoelectronics Engineering/International Semiconductor College Chongqing University of Posts and TelecommunicationsChongqing 400065China

With the wide application of the fifth-generation mobile communication system(5G)technology,wireless communication equipment tends to develop in miniaturization,high frequency,and low *** this paper,a surface acoustic wave(SAW)filter with a center frequency of 3.5 GHz was ***,the acoustic waveguide structure of the longitudinal leaky SAW(LLSAW)excitation is determined,and the two-dimensional(2D)theoretical model of the device is established by COMSOL ***,the influence of electrode parameters on the performance of the device is studied,and the electrode parameters are optimized on this *** setting the device structure parameters reasonably,the spurious in the passband can be effectively ***,the center frequency of the mirror T-structure LLSAW filter is 3.536 GHz,the insertion loss is-1.414 dB,the bandwidth of-3 dB is 276 MHz,and the out-of-band rejection is greater than-30 dB.

关键词： surface acoustic wave(SAW) electrode spurious response mirror T-structure

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

Enhanced organic degradation and microbial community cooperation by inoculating Bacillus licheniformis in low temperature composting

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Journal of Environmental Sciences 2024年第9期143卷 189-200页

作者： Jing Su Kaiyun Zhou Wenjie Chen Shaoqi Xu Ziwei Feng Yuan Chang Xiaoyan ding Yi Zheng Xingling Tao Ake Zhang Yue Wang Ji Li guochun ding Yuquan wei Nanjing Institute of Environmental Sciences Ministry of Ecology and EnvironmentNanjing 210042China College of Resources and Environmental Science Beijing Key Laboratory of Biodiversity and Organic FarmingChina Agricultural UniversityBeijing 100193China Organic Recycling Institute(Suzhou)of China Agricultural University Wuzhong DistrictSuzhou 215128China Fuyang Academy of Agricultural Sciences Fuyang 236065China

Microbial activity and interaction are the important driving factors in the start-up phase of food waste composting at low *** aim of this study was to explore the effect of inoculating Bacillus licheniformis on the degradation of organic components and the potential microbe-driven mechanism from the aspects of organic matter degradation,enzyme activity,microbial community interaction,and microbial metabolic *** results showed that after inoculating ***,temperature increased to 47.8℃ on day2,and the degradation of readily degraded carbohydrates(RDC)increased by 31.2%,and the bioheat production increased by 16.5%.There was an obvious enhancement of extracellular enzymes activities after inoculation,especially amylase activity,which increased by 7.68 times on day *** inoculated *** colonized in composting as key genus in the start-up *** network analysis and Mantel test indicated that inoculation drove the cooperation between microbial network modules who were responsible for various organic components(RDC,lipid,protein,and lignocellulose)degradation in the start-up *** function prediction suggested that carbohydrate metabolisms including starch and sucrose metabolism,glycolysis/gluconeogenesis,pyruvate metabolism,etc.,were improved by increasing the abundance of related functional genes after *** conclusion,inoculating *** accelerated organic degradation by driving the cooperation between microbial network modules and enhancing microbial metabolism in the start-up phase of composting.

关键词： Microbial agent Organic matter degradation Microbial interaction Food waste Low temperature composting

Occurrence and prevention of incisional hernia following laparoscopic colorectal surgery

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 1973-1980页

作者： Xi-Wen Wu ding-Quan Yang Ming-wei Wang Yan Jiao The First Operating Room The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Gastrointestinal and Colorectal Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Ministry of Health Key Laboratory of Radiobiology School of Public Health of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Hepatobiliary and Pancreatic Surgery General Surgery CenterThe First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

Among minimally invasive surgical procedures,colorectal surgery is associated with a notably higher incidence of incisional hernia(IH),ranging from 1.7% to 24.3%.This complication poses a significant burden on the healthcare system annually,necessitating urgent attention from *** a study published in the World Journal of Gastrointestinal Surgery,Fan et al compared the incidence of IH among 1614 patients who underwent laparoscopic colorectal surgery with different extraction site locations and evaluated the risk factors associated with its *** editorial analyzes the current risk factors for IH after laparoscopic colorectal surgery,emphasizing the impact of obesity,surgical site infection,and the choice of incision location on its ***,we summarize the currently available preventive measures for *** the low surgical repair rate and high recurrence rate associated with IH,prevention deserves greater research and attention compared to treatment.

关键词： Incisional hernia Laparoscopy Colorectal surgery Risk factor Prevention

Solid-state NMR study of the stability of MOR framework aluminum

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Chinese Journal of Structural Chemistry 2024年第4期43卷 7-14页

作者： Xinzhi ding Chong Liu Jing Niu Nan Chen Shutao Xu Yingxu wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing 100049China School of Chemistry Dalian University of TechnologyDalian116024China

MOR zeolite has been effectively utilized for dimethyl ether(DME)carbonylation reaction due to its unique pore structure and *** industrial production,the transformation of ammonium type MOR zeolite(NH_(4)-MOR)into proton type MOR zeolite(H-MOR)causes inevitable ***,understanding the influencing factors and dynamic evolution mechanism of zeolite dealumination is *** this work,the stability of framework aluminum was studied by X-ray diffraction(XRD),Fourier transform infrared(FT-IR)spectroscopy,^(29)Si,^(27)Al,^(1)H magic angle spinning nuclear magnetic resonance(MAS NMR),and DME carbonylation performance *** results indicate that extra-framework cation Na^(+)and NH_(4)^(+)could better preserve the aluminum structure of the MOR zeolite framework compared to H^(+),primarily due to the different'attraction'of the framework to ***,the impact of water on the zeolite framework aluminum at high temperature was studied by manipulating the humidity of the calcination atmosphere,revealing the formation of extra-framework six-coordinated aluminum(Al(Ⅵ)-EF)and the mechanism of water influence on the zeolite framework aluminum.

关键词： H-MOR Solid-state NMR H2O Framework aluminum stability Dealumination