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Rare Metals 2024年第9期43卷 4367-4376页

作者： Wei Chen Ya-Hui Sun Tian Xu Xue-Bin yu Guang-Lin xia Department of Materials Science Fudan UniversityShanghai 200433China

2LiBH_(4)-MgH_(2)composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of MgB_(2)during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles(AT NPs)are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of 2LiBH_(4)-MgH_(2)*** the initial H_(2)desorption process,MgAlB_(4)and TiB_(2)that have identical crystal structure and low d-value mismatch with MgB_(2)resulting from the reaction between AT NPs and 2LiBH_(4)-MgH_(2)composite serve as effective nucleation sites for the formation of MgB_(2).As a result,the apparent activation energy of the two-step H_(2)desorption of AT NPs doped 2LiBH_(4)-MgH_(2)composite are notably decreased to(110.0±5.9)and(119.6±1.4)kJ·mol^(-1),which is 55.5 and 33.5 kJ·mol^(-1)lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H_(2)desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Reversible hydrogen storage Reactive hydride composites Catalytic effects Heterogeneous nucleation

Urinary metabolic profiles during Helicobacter pylori eradication in chronic gastritis

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World Journal of Clinical Cases 2024年第5期12卷 951-965页

作者： Wen-Ting An yu-xia Hao Hong-xia Li Xing-Kang Wu Department of Pharmacy Shanxi Provincial People’s HospitalTaiyuan 030012Shanxi ProvinceChina Department of Gastroenterology Shanxi Provincial People's HospitalTaiyuan 030012Shanxi ProvinceChina Department of Oncology Shanxi Provincial People’s HospitalTaiyuan 030012Shanxi ProvinceChina Modern Research Center for Traditional Chinese Medicine Shanxi UniversityTaiyuan 030006Shanxi ProvinceChina

BACKGROUND Helicobacter pylori(***)infection is a major risk factor for chronic gastritis,affecting approximately half of the global *** eradication is a popular treatment method for ***-positive chronic gastritis,but its mecha-nism remains *** metabolomics has been used to elucidate the mechanisms of gastric disease ***,no clinical study has been conducted on urinary metabolomics of chronic *** To elucidate the urinary metabolic profiles during *** eradication in patients with chronic *** We applied LC–MS-based metabolomics and network pharmacology to in-vestigate the relationships between urinary metabolites and ***-positive chronic gastritis via a clinical follow-up *** Our study revealed the different urinary metabolic profiles of ***-positive chronic gastritis before and after *** *** metabolites regulated by *** eradication therapy include cis-aconitic acid,isocitric acid,citric acid,L-tyrosine,L-phenylalanine,L-tryptophan,and hippuric acid,which were involved in four metabolic pathways:(1)Phenylalanine metabolism;(2)phenylalanine,tyrosine,and tryptophan biosynthesis;(3)citrate cycle;and(4)glyoxylate and dicarboxylate *** metabolomics and network pharmacology revealed that MPO,COMT,TPO,TH,EPX,CMA1,DDC,TPH1,and LPO were the key proteins involved in the biological progress of *** eradication in chronic *** Our research provides a new perspective for exploring the significance of urinary metabolites in evaluating the treatment and prognosis of ***-positive chronic gastritis patients.

关键词： LC-MS metabolomics chronic gastritis Helicobacter pylori urinary metabolites

Illuminating spin-crossover octanuclear metal-organic cages

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Science China Chemistry 2024年第4期67卷 1208-1215页

作者： Zhi-Kun Liu Alyona A.Starikova yu-xia Li Ke Sun Meng yu Zi-Shuo Yao Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China Institute of Physical and Organic Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical properties,such as fluorescence and magneto-optical *** this study,we synthesized three octanuclear metal-organic cages(MOCs)using tetraphenylethylene-based luminophores,aldehydes,and Fe^(Ⅱ)salts,by subcomponent self-assembly approach,namely[Fe1]-[Fe3].By controlling the ligand-field strength and guest encapsulation,we finely tuned their SCO *** them,MOC[Fe2]displayed nearly complete SCO behavior in the solid state,which is rare for high-nuclearity *** also demonstrated the coupling of SCO with fluorescence emission in these MOCs by using isostructural Zn^(Ⅱ)complexes([Zn1]-[Zn3])as control experiments,for the first *** calculations revealed the energy-transfer mechanism between fluorophores and SCOactive centers,which emphasizes the significant contribution of d-d transitions in the interplay between the occurrence of SCO and fluorescence emission.

关键词： metal-organic cages spin crossover fluorescence switching materials DFT calculation

Analysis of Intelligent Equipment Usage for Work-Related Musculoskeletal Disorders Prevention in Miners—Shanxi Province,China,2023

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China CDC weekly 2024年第34期6卷 862-866页

作者： Haimiao yu Zepeng Xu Ying xia Shuo Zhang xiaoting Jia School of Economics and Management China University of Mining and TechnologyXuzhouJiangsu ProvinceChina Administrators Training Center National Health Commission of the People’s Republic of ChinaBeijingChina

Summary What is already known about this topic?Work-related musculoskeletal disorders(WMSDs)are prevalent in the workforce and occur across various *** show that the prevalence of WMSDs among miners is generally over 50%.What is added by this report?High levels of intelligent equipment usage(IEU)can decrease the prevalence of WMSDs among miners by 7.49%and reduce pain by 13.69%on average.

关键词： WMS Work skeletal

Elemental Compositions of Clinopyroxenes from Southern Okinawa Trough Basalt:Implications for Magmatism and Structural Environment in an Initial Back-Arc Basin

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Journal of Ocean University of China 2024年第3期23卷 643-653页

作者： GUO Kun ZHAI Shikui FAN Di ZHANG xia ZHANG yu ZHU Zhimin Laoshan Laboratory Qingdao 266237China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

The major and trace elemental compositions of clinopyroxene from basalt were used to characterize the nature of the primitive magma and structural environment beneath the southern Okinawa Trough(SOT),which is an initial back-arc basin at a continental *** clinopyroxenes in the basalt were augite with variable Mg^(#)contents(73.37-78.22).The regular variations in major oxide contents(i.e.,CaO,FeO,TiO_(2),and Cr)with decreasing Mg#implied that the clinopyroxenes evolved from being enriched in Mg,Ca,and Cr to being enriched in Fe and *** clinopyroxenes had relatively low rare earth element concentrations(7.51×10^(-6) to 12.68×10^(-6))and negative Eu anomalies(δEu=0.67-0.95).The Kd_(cpx) values of clinopyroxenes(0.2-0.26),which were used to examine whether the clinopyroxene was equilibrated with its host basalt,demonstrate that these clinopyroxene phenocrysts were not captured crystals but were instead produced by crystallization differentiation of the *** calculated clinopyroxene crystallization temperatures showed a narrow range of 990-1061℃,and their crystallization pressures ranged from 2.0 to 3.2 *** geochemistry features of these clinopyroxenes indicated that the parent magma belonged to the subalkaline tholeiitic magma series and suggested that the magma experienced crystallization differentiation of olivine,plagioclase,and clinopyroxene,where the crystallization of plagioclase occurred earlier than that of *** with geophysical data,this research on primitive magma and its crystallization differentiation from clinopyroxene indicates that the SOT is in the stage of‘seafloor spreading’and that basaltic rocks produced from tholeiitic magma represent the generation of oceanic crust.

关键词： trace elements clinopyroxenes southern Okinawa Trough seafloor spreading back-arc basin

Toward a rapid and convenient nanoplastic quantification method in laboratory-scale study based on fluorescence intensity

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 117-126页

作者： Ruiqi Yan Sen Lin Qian Ding Lei Zhang xia.yu Wentao Zhao Qian Sui State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process School of Resources and Environmental EngineeringEast China University of Science and TechnologyShanghai200237China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092China

The thorough investigation of nanoplastics(NPs)in aqueous environments requires efficient and expeditious quantitative analytical methods that are sensitive to environmentally relevant NP concentrations and convenient to *** analysis-based quantitative methods have been acknowledged as effective and rapid approaches for quantifying NP concentrations in laboratory-scale ***,we compared three commonly used optical response indicators,namely fluorescence intensity(FI),ultraviolet absorbance,and turbidity,to assess their performance in quantifying ***,orthogonal experiments were conducted to evaluate the influence of various water quality parameters on the preferred indicator-based quantification *** results revealed that FI exhibits the highest correlation coefficient(>0.99)with NP ***,the limit of quantification(LOQ)for various types of NPs is exceptionally low,ranging from 0.0089 to 0.0584 mg/L in ultrapure water,well below environmentally relevant *** variations in water quality parameters such as pH,salinity,suspended solids(SS),and humic acid,a robust relationship between detectable FI and NP concentration was ***,an increased matrix,especially SS in water samples,results in an enhanced LOQ for ***,the quantitative method remains applicable in real water bodies,especially in drinking water,with NP LOQ as low as 0.0157–0.0711 mg/*** exceeds the previously reported detectable concentration for 100 nm NPs at 40µg/mL using surface-enhanced Raman *** study confirms the potential of FI as a reliable indicator for the rapid quantification of NPs in aqueous environments,offering substantial advantages in terms of both convenience and cost-effectiveness.

关键词： Nanoplastic quantification Fluorescence intensity Drinking water Limit of quantification(LOQ) Matrix effects

Breaking the Fe_(3)O_(4)-wrapped copper microstructure to enhance copper-slag separation

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2312-2325页

作者： xiaopeng Chi Haoyu Liu Jun xia Hang Chen xiangtao yu Wei Weng Shuiping Zhong Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China Fujian Key Laboratory of Green Extraction and High-Value Utilization of New Energy Metals Fuzhou UniversityFuzhou 350108China Zijin Mining Group Co. Ltd.Longyan 364200China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China

The precipitation of Fe_(3)O_(4)particles and the accompanied formation of Fe_(3)O_(4)-wrapped copper structure are the main obstacles to copper recovery from the molten slag during the pyrometallurgical smelting of copper ***,the commercial powdery pyrite or anthracite is replaced with pyrite-anthracite pellets as the reductants to remove a large amount of Fe_(3)O_(4)particles in the molten slag,resulting in a deep fracture in the Fe_(3)O_(4)-wrapped copper microstructure and the full exposure of the copper matte *** 1wt%composite pellet is used as the reductant,the copper matte droplets are enlarged greatly from 25μm to a size observable by the naked eye,with the copper content being enriched remarkably from 1.2wt%to 4.5wt%.Density functional theory calculation results imply that the formation of the Fe_(3)O_(4)-wrapped copper structure is due to the preferential adhesion of Cu_(2)S on the Fe_(3)O_(4)particles.X-ray photoelectron spectroscopy,Fourier transform infrared spectrometer(FTIR),and Raman spectroscopy results all reveal that the high-efficiency conver-sion of Fe_(3)O_(4)to FeO can decrease the volume fraction of the solid phase and promote the depolymerization of silicate network *** a consequence,the settling of copper matte droplets is enhanced due to the lowered slag viscosity,contributing to the high efficiency of copper-slag separation for copper *** results provide new insights into the enhanced in-situ enrichment of copper from mol-ten slag.

关键词： pyrometallurgical smelting process slag cleaning reductants copper matte

Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits

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International Journal of Mining Science and Technology 2024年第4期34卷 507-520页

作者： Zuchao Liang Dong Wang Guanghe Li Guangyu Sun Mingyu yu Dong xia Chunjian Ding College of Mining Engineering Liaoning Technical UniversityFuxin 123000China Inner Mongolia Pingxi Baiyinhua Coal Industry Co. Ltd.Xilingol League 026000China Guoneng Baorixile Energy Co. Ltd.Hulunbuir 021008China

The 2D limit equilibrium method is widely used for slope stability ***,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical ***,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope *** the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding *** integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is ***,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is *** analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear *** spatial form equation of the sliding mass comprises an ellipsoid and weak plane *** analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite ***,the3D stability coefficient of the composite slope exhibits an exponential co

关键词： Composite slope Destabilization mechanism 3D mechanical effect Three-dimensional stability Coordinated development distance

Investigation on occupant presence and appliance operation schedules for university campus in south China sub-tropical area

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Building Simulation 2024年第2期17卷 301-318页

作者： Siwei Lou Zhongyuan Lin yukai Zou Dawei xia.yu Huang Zhuohong Li Zhaowen Gu School of Civil Engineering Guangzhou UniversityGuangzhou Higher Edu.Mega CenterGuangzhouChina School of Architecture and Urban Planning Guangzhou UniversityGuangzhou Higher Edu.Mega CenterGuangzhouChina

Building occupant presence during varying periods is crucial to the performance studies of buildings and city ***,the understanding of the building occupancies on the university campus remains *** address this gap,our study employs field measurements,payment records,course arrangements,and building access systems to depict the occupancy patterns of the canteen,dormitory,library,and teaching and lab buildings during weekdays and *** found that the occupancy rates across different buildings are somehow interrelated,given that the total number of occupants on campus is generally ***,dormitory occupancy rates tend to be low during the morning and afternoon course hours,which inversely correlates with the high occupancy rates in the teaching and lab buildings during these ***,canteens experience surges in occupancy during meal times,which coincide with a decrease in library ***,we established appliance operation schedules for dormitories through surveys and on-site *** dispensers and electronic devices were identified as the primary energy consumers for both male and female occupants,with desk-top fans and hairdryers being significant energy users for male and female occupants,*** findings are essential for energy studies within a campus setting,underlining the importance of considering occupant behaviors on a regional scale.

关键词： building occupant behavior university campus occupancy schedule appliance operation schedule

Metal-to-insulator transition in platinum group compounds

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Rare Metals 2024年第8期43卷 3460-3474页

作者： yu-Xuan xia Jian-Gang He Nuo-Fu Chen Ji-Kun Chen School of New Energy North China Electric Power UniversityBeijing102206China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China Key Laboratory of Advanced Materials and Devices for PostMoore Chips(Ministry of Education) School of Materials Science and EngineeringJniversity of Science and Technology BeijingBeijing 100083China

The metal-to-insulator transition(MIT) as usually achieved in 3d-orbital transitional metal(TM) compounds opens up a new paradigm in correlated electronics via triggering abrupt variations in their transportation *** to such 3d-orbital TM compounds,the MIT within the platinum group(Pg) element compounds based on the 4d-and 5d-orbital configurations is more complicated,owing to their elevation in the spinorbit coupling and meanwhile weakened intra-atomic Coulomb *** brings in a new freedom to regulate the balance in their metallic or semiconductive orbital configurations,while their MIT properties can be potentially combined with their spintronic properties to enable new electronic ***,we review the electronic transport and MIT behaviors within the existing family of Pg-containing compounds,particularly those showing first-order MIT behaviors that can be useful in correlated *** is also hoped that summarizing the presently reported Pg-containing MIT compounds will lead to the discovery of more new material families and/or new mechanisms associated with the Pg-containing compounds showing MIT properties.

关键词： Metal-to-insulator transition Platinum group compounds Electron correlation Spin-orbital coupling