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CAPACITIVE DROP ANALYSER FOR MEASURING PHYSICAL PROPERTIES OF LIQUIDS
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作者 王春海 张国雄 《Transactions of Tianjin University》 EI CAS 1999年第2期19-24,共6页
A new instrument called capacitive drop analyser (CDA) for measuring the physical properties of liquid is developed.A delivery head with a specialized wetting design was constructed for forming drops.The capacitive tr... A new instrument called capacitive drop analyser (CDA) for measuring the physical properties of liquid is developed.A delivery head with a specialized wetting design was constructed for forming drops.The capacitive transducer uses the delivery head as one of its plates and a cylindrical ring plate.Excellent linearity is achieved by optimising the design,with an accuracy of drop volume measurement of approximately 2 μL.It is suitable for measuring both drops in equilibrium and those in the process of growing.Its capability of real time measurement makes it particularly useful for volatile liquids,in which instance the measurement of drop volume using a flowmeter or a pump is no longer reliable.The CDA can also be used to determine concentration.It is found that concentration curve is linear for aqueous glycerol solutions although not so for aqueous ethanol solution.The CDAs capability of measuring surface tension is also explored and experimental results are presented. 展开更多
关键词 capacitive drop analyser LIQUID DROPS
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Development of x-ray scintillator functioning also as an analyser grating used in grating-based x-ray differential phase contrast imaging 被引量:4
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作者 雷耀虎 刘鑫 +2 位作者 郭金川 赵志刚 牛憨笨 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期222-227,共6页
In order to push the grating-based phase contrast imaging system to be used in hospitM and laboratories, this paper designs and develops a novel structure of x-ray scintillator functioning also as an analyser grating,... In order to push the grating-based phase contrast imaging system to be used in hospitM and laboratories, this paper designs and develops a novel structure of x-ray scintillator functioning also as an analyser grating, which has been proposed for grating-based x-ray differential phase contrast imaging. According to this design, the scintillator should have a periodical structure in one dimension with the pitch equaling the period of self-image of the phase grating at the Talbot distance, where one half of the pitch is pixellated and is made of x-ray sensitive fluorescent material, such as CsI(T1), and the remaining part of the pitch is made of x-ray insensitive material, such as silicon. To realize the design, a deep pore array with a high aspect ratio and specially designed grating pattern are successfully manufactured on 5 inch silicon wafer by the photo-assisted electrochemical etching method. The related other problems, such as oxidation-caused geometrical distortion, the filling of CsI(T1) into deep pores and the removal of inside bubbles, have been overcome. Its pixel size, depth and grating pitch are 3 p.m^7.5 ~m, 150 p^m and 3 Ixm, respectively. The microstructure of the scintillator has been examined microscopically and macroscopically by scanning electron microscope and x-ray resolution chart testing, respectively. The preliminary measurements have shown that the proposed scintillator, also functioning as an analyser grating, has been successfully designed and developed. 展开更多
关键词 scintillator screen pore arrays oxidation CsI(T1) analyser grating
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Lie algebraic analysis for the beam transport in the spherical electrostatic analyser 被引量:1
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作者 吕建钦 张卓 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1280-1284,共5页
This paper uses the Lie algebraic method to analyse the charged particle trajectories in the spherical electrostatic analyser, and obtains the nonlinear solutions. The results show that the focusing abilities both in ... This paper uses the Lie algebraic method to analyse the charged particle trajectories in the spherical electrostatic analyser, and obtains the nonlinear solutions. The results show that the focusing abilities both in the x and y directions of the analyser are almost the same. Moreover, there exist dispersion effects in the x direction, and no dispersion effects in the y direction. 展开更多
关键词 Lie algebraic method spherical electrostatic analyser optical properties NONLINEARITY
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An optical method for wavelength fine-selection in optical spectrum analysers 被引量:2
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作者 廖廷弟 邱怡申 徐惠贞 《Chinese Optics Letters》 SCIE EI CAS CSCD 2004年第9期552-554,共3页
This letter describes a novel optical method for wavelength fine-selection in the optical spectrum analysers (OSAs) for dense wavelength division multiplexing (DWDM) applications. The proposed new method employs a ... This letter describes a novel optical method for wavelength fine-selection in the optical spectrum analysers (OSAs) for dense wavelength division multiplexing (DWDM) applications. The proposed new method employs a 'refractive optical lever' system consisting of a rotating optical wedge prism. A new OSA system based on Littman-type monochromator is proposed and the wavelength selection accuracy and resolution of OSA that has included such an optical lever system have been improved by a factor of 20 to 100 depending on the wedge angle and offset orientation angle of the optical wedge prism. This proposed 'refractive optical lever' may also simplify the rotation mechanism of the mirror in the commercially available OSAs. 展开更多
关键词 An optical method for wavelength fine-selection in optical spectrum analysers DWDM OSA
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Association of Loneliness and Social Isolation with Ischemic Heart Disease: A Bidirectional and Network Mendelian Randomization Study 被引量:1
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作者 Shuyao Su Wanyue Wang +3 位作者 Chenxi Yuan Zhennan Lin Xiangfeng Lu Fangchao Liu 《Biomedical and Environmental Sciences》 2025年第3期351-364,共14页
Objective Observational studies have shown inconsistent associations of loneliness or social isolation(SI)with ischemic heart disease(IHD),with unknown mediators.Methods Using data from genome-wide association studies... Objective Observational studies have shown inconsistent associations of loneliness or social isolation(SI)with ischemic heart disease(IHD),with unknown mediators.Methods Using data from genome-wide association studies of predominantly European ancestry,we performed a bidirectional two-sample Mendelian Randomization(MR)study to estimate causal effects of loneliness(N=487,647)and SI traits on IHD(N=184,305).SI traits included whether individuals lived alone,participated in various types of social activities,and how often they had contact with friends or family(N=459,830 to 461,369).A network MR study was conducted to evaluate the mediating roles of 20 candidate mediators,including metabolic,behavioral and psychological factors.Results Loneliness increased IHD risk(OR=2.129;95%confidence interval[CI]:1.380 to 3.285),mediated by body fat percentage,waist-hip ratio,total cholesterol,and low-density lipoprotein cholesterol.For SI traits,only fewer social activities increased IHD risk(OR=1.815;95%CI:1.189 to 2.772),mediated by hypertension,high-density lipoprotein cholesterol,triglycerides,fasting insulin,and smoking cessation.No reverse causality of IHD with loneliness and SI was found.Conclusion These findings suggested more attention should be paid to individuals who feel lonely and have fewer social activities to prevent IHD,with several mediators as prioritized targets for intervention. 展开更多
关键词 Mendelian randomization LONELINESS Social isolation Ischemic heart disease Mediation analyses
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Reevaluating health metrics:Unraveling the limitations of disabilityadjusted life years as an indicator in disease burden assessment
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作者 Ariel Beresniak Dominique Bremond-Gignac +1 位作者 Danielle Dupont Gerard Duru 《World Journal of Methodology》 2025年第1期14-19,共6页
In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALY)as a novel indicator.The DALY,a composite metric incorporating temporal and quali... In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALY)as a novel indicator.The DALY,a composite metric incorporating temporal and qualitative data,is grounded in preferences regarding disability status.This review delineates the algorithm used to calculate the value of the proposed DALY synthetic indicator and elucidates key methodological challenges associated with its application.In contrast to the quality-adjusted life years approach,derived from multi-attribute utility theory,the DALY stands as an independent synthetic indicator that adopts the assumptions of the Time Trade Off utility technique to define Disability Weights.Claiming to rely on no mathematical or economic theory,DALY users appear to have exempted themselves from verifying whether this indicator meets the classical properties required of all indicators,notably content validity,reliability,specificity,and sensitivity.The DALY concept emerged primarily to facilitate comparisons of the health impacts of various diseases globally within the framework of the Global Burden of Disease initiative,leading to numerous publications in international literature.Despite widespread adoption,the DALY synthetic indicator has prompted significant methodological concerns since its inception,manifesting in inconsistent and non-reproducible results.Given the substantial diffusion of the DALY indicator and its critical role in health impact assessments,a reassessment is warranted.This reconsideration is imperative for enhancing the robustness and reliability of public health decisionmaking processes. 展开更多
关键词 Disability adjusted life years Cost-utility analyses Outcome research Public health Burden of disease
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Morphotectonic Analyses of LiDAR-Derived DEMs:Insights into Tectonic Activity of the Xinhua Fault within the Three Gorges Area(Central China)
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作者 Xiaofeng Wang Xiaohan Yin +4 位作者 Tonghui Liu Xuan Li Hongming Wang Yaqi Zhong Gang Rao 《Journal of Earth Science》 2025年第2期823-829,共7页
0 INTRODUCTION.The global availability of digital elevation model(DEM)data,such as 90-m Shuttle Radar Topography Mission(SRTM)DEM and 30-m Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital ... 0 INTRODUCTION.The global availability of digital elevation model(DEM)data,such as 90-m Shuttle Radar Topography Mission(SRTM)DEM and 30-m Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM),has been extensively utilized in morphotectonic analyses(e.g.,Wang et al.,2024;Cheng et al.,2018;Pérez-Pe?a et al.,2010;El Hamdouni et al.,2008). 展开更多
关键词 xinhua fault morphotectonic analyses egwang three gorges area digital elevation model aster lidar derived dems tectonic activity morphotectonic analyses digital elevation model dem datasuch
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Brivaracetam and rufinamide combination increased seizure threshold and improved neurobehavioral deficits in corneal kindling model of epilepsy
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作者 Awais Sattar Zohabia Rehman +4 位作者 Hammad Murtaza Waseem Ashraf Tanveer Ahmad Faleh Alqahtani Imran Imran 《Animal Models and Experimental Medicine》 2025年第2期209-221,共13页
Background:Besides seizures,a myriad of overlapping neuropsychiatric and cognitive comorbidities occur in patients with epilepsy,which further debilitates their quality of life.This study provides an in-depth characte... Background:Besides seizures,a myriad of overlapping neuropsychiatric and cognitive comorbidities occur in patients with epilepsy,which further debilitates their quality of life.This study provides an in-depth characterization of the impact of brivaracetam and rufinamide individually and in combination at 10 and 20 mg/kg doses,respec-tively,on corneal kindling-induced generalized seizures and behavioral alterations.Furthermore,observed convulsive frequency and behavioral changes were corre-lated to post-kindling-induced changes in the activity of markers of oxidative stress.Methods:Adult C57BL/6 mice were kindled via twice-daily transcorneal 50-Hz elec-trical stimulations(3 mA)for 3 s for 12 days until animals reached a fully kindled state.After the kindling procedure,animals were tested using a set of behavioral tests,and neurochemical alterations were assessed.Results:Corneal-kindled animals exhibited intense generalized convulsions,altered behavioral phenotypes typified by positive symptoms(hyperlocomotion),negative symptoms(anxiety and anhedonia),and deficits in semantic and working memory.BRV 10+RFM 20 dual regime increased convulsive threshold and propensity toward the start of stage 4–5 seizures and improved phenotypical deficits,that is,anxiety,depression,and memory impairments.Moreover,this combination therapy mitigated kindling-induced redox impairments as evidenced by reduced malondialdehyde and acetylcholinesterase levels and increased glutathione antioxidant activity in the brain of animals subjected to repetitive brain insult.Conclusion:Based on our outcomes,this dual therapy provides supporting evidence in alleviating epilepsy-induced neurobehavioral comorbidities and changes in redox homeostasis. 展开更多
关键词 BRIVARACETAM corneal kindling EPILEPSY neurobehavioral analyses oxidative stress RUFINAMIDE
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Profiling and bioinformatics analyses of circular RNAs in myocardial ischemia/reperfusion injury model in mice
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作者 Jiao-Ni Wang Ying-Ying Zhou +1 位作者 Yong-Wei Yu Jun Chen 《World Journal of Cardiology》 2025年第1期65-77,共13页
BACKGROUND Myocardial ischemia/reperfusion(I/R)injury,which is associated with high morbidity and mortality,is a main cause of unexpected myocardial injury after acute myocardial infarction.However,the underlying mech... BACKGROUND Myocardial ischemia/reperfusion(I/R)injury,which is associated with high morbidity and mortality,is a main cause of unexpected myocardial injury after acute myocardial infarction.However,the underlying mechanism remains unclear.Circular RNAs(circRNAs),which are formed from protein-coding genes,can sequester microRNAs or proteins,modulate transcription and interfere with splicing.Authoritative studies suggest that circRNAs may play an important role in myocardial I/R injury.AIM To explore the role and mechanism of circRNAs in myocardial I/R injury.METHODS We constructed a myocardial I/R injury model using ligation of the left anterior descending coronary artery,and evaluated the success of the validated model using triphenyltetrazolium chloride and hematoxylin-eosin staining.Then,left ventricular samples from different groups were selected for mRNA-sequence,and differential gene screening was performed on the obtained results.The differentially obtained mRNAs were divided into up-regulated and down-regulated according to their expression levels,and Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment analysis were performed,respectively.Then,the obtained circRNA and microRNA(miRNA)were paired for analysis,and the binding sites of miRNA and mRNA were virtual screened.Finally,the obtained circRNA,miRNA and mRNA were constructed by ceRNA mutual most useful network.RESULTS We used an RNA sequencing array to investigate the expression signatures of circRNAs in myocardial I/R injury using three samples from the I/R group and three samples from the sham group.A total of 142 upregulated and 121 downregulated circRNAs were found to be differentially expressed(fold change≥2,P<0.05).GO and KEGG functional analyses of these circRNAs were performed.GO analysis revealed that these circRNAs were involved mainly in cellular and intracellular processes.KEGG analysis demonstrated that 6 of the top 20 pathways were correlated with cell apoptosis.Furthermore,a circRNA-miRNA coexpression network and ceRNA network based on these genes were constructed,revealing that mmu-circ-0001452,mmu-circ-0001637,and mmu-circ-0000870 might be key regulators of myocardial I/R injury.CONCLUSION This research provides new insights into the mechanism of myocardial I/R,which mmu-circ-0001452,mmu-circ-0001637,and mmu-circ-0000870 are expected to be new therapeutic targets for myocardial I/R injury. 展开更多
关键词 Rna-sequencing Circular RNA MicroRNA CeRNA Myocardial ischemia/reperfusion Bioinformatics analyses
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A DFE2-SPCE Method for Multiscale Parametric Analysis of Heterogenous Piezoelectric Materials and Structures
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作者 Qingxiang Pei Fan Li +2 位作者 Ziheng Fei Haojie Lian Xiaohui Yuan 《Computers, Materials & Continua》 2025年第4期79-96,共18页
This paper employs the Direct Finite Element Squared(DFE2)method to develop Sparse Polynomial Chaos Expansions(SPCE)models for analyzing the electromechanical properties of multiscale piezoelectric structures.By incor... This paper employs the Direct Finite Element Squared(DFE2)method to develop Sparse Polynomial Chaos Expansions(SPCE)models for analyzing the electromechanical properties of multiscale piezoelectric structures.By incorporating variations in piezoelectric and elastic constants,the DFE2 method is utilized to simulate the statistical characteristics—such as expected values and standard deviations—of electromechanical properties,including Mises stress,maximum in-plane principal strain,electric potential gradient,and electric potential,under varying parameters.This approach achieves a balance between computational efficiency and accuracy.Different SPCE models are used to investigate the influence of piezoelectric and elastic constants on multiscale piezoelectric materials.Additionally,the multiscale parameterization study investigates how microscale material properties affect the macroscopic response of these structures and materials. 展开更多
关键词 DFE2 SPCE piezoelectric structures parameter analyses
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Cellular automata models for simulation and prediction of urban land use change:Development and prospects
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作者 Baoling Gui Anshuman Bhardwaj Lydia Sam 《Artificial Intelligence in Geosciences》 2025年第2期24-39,共16页
Rapid urbanization and land-use changes are placing immense pressure on resources,infrastructure,and envi-ronmental sustainability.To address these,accurate urban simulation models are essential for sustainable develo... Rapid urbanization and land-use changes are placing immense pressure on resources,infrastructure,and envi-ronmental sustainability.To address these,accurate urban simulation models are essential for sustainable development and governance.Among them,Cellular Automata(CA)models have become key tools for pre-dicting urban expansion,optimizing land-use planning,and supporting data-driven decision-making.This review provides a comprehensive examination of the development of urban cellular automata(UCA)models,presenting a new framework to enhance individual UCA sub-modules within the context of emerging technologies,sus-tainable environments,and public governance.By addressing gaps in prior UCA modelling reviews-particularly in the integration and optimization of UCA sub-module technologies-this framework is designed to simplify UCA model understanding and development.We systematically review pioneering case studies,deconstruct current UCA operational processes,and explore modern technologies,such as big data and artificial intelligence,to optimize these sub-modules further.We discuss current limitations within UCA models and propose future pathways,emphasizing the necessity of comprehensive analyses for effective UCA simulations.Proposed solu-tions include strengthening our understanding of urban growth mechanisms,examining spatial positioning and temporal evolution dynamics,and enhancing urban geographic simulations with deep learning techniques to support sustainable transitions in public governance.These improvements offer data-driven decision support for environmental management,advancing policies that foster sustainable urban development. 展开更多
关键词 Cellular automata Spatiotemporal analyse Urban change Land use change SIMULATION
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Seasonal Evolution of Eocene Saline Lakes in Eastern China:A Case Study of‘Bamboo-like’Rock Salt in the Shizhai Depression,Northern Jiangsu Province
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作者 XU Yang LIU Chenglin +3 位作者 YANG Sibo CAO Yangtong WEN Longtao LI Ruiqin 《Acta Geologica Sinica(English Edition)》 2025年第3期879-895,共17页
The phenomenon of'bamboo-like'thin interlayers developed in rock salt is one of the most prominent features of Paleogene salt-bearing strata in eastern China,where centimeter-thick rock salts appear separately... The phenomenon of'bamboo-like'thin interlayers developed in rock salt is one of the most prominent features of Paleogene salt-bearing strata in eastern China,where centimeter-thick rock salts appear separately,forming rhythmic units.At present,detailed analyses of these rhythms of rock salt are still limited,which directly affects the achievement of comprehensive and in-depth understanding of the developmental laws pertaining to this kind of saline lake.Therefore,we selected the typical rhythmic'bamboo-like'rock salts of the Shizhai Depression in Jiangsu Province as the research subject.Through careful observation of rock salts in hand samples and detailed petrographic and mineralogical analyses,we analyzed the hydrogen and oxygen isotopic compositions,homogenization temperatures and chemical compositions of individual fluid inclusions in halite crystals.Early-stage rhythmic deposition was a product of continental saline lake evolution in winter or spring,late-stage rhythmic deposition being the product of evolution in the summer.The seasonal evolution of the halite sequences was determined and two brine enrichment events were identified.In addition,the quiet saline lake environment with concentrated brine represented by rock salt was more likely to precipitate potassium.This study provides a new reference for the evolution of both Paleogene climate and saline lakes in eastern China. 展开更多
关键词 halite fluid inclusions LA-ICP-MS quantitative analyses seasonal evolution eastern China
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Plates, Beams and Shells Reinforced by CNTs or GPLs: A Review on Their Structural Behavior and Computational Methods
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作者 Mohammad Javad Bayat Amin Kalhori +1 位作者 Kamran Asemi Masoud Babaei 《Computer Modeling in Engineering & Sciences》 2025年第2期1351-1458,共108页
Since the initial observation of carbon nanotubes(CNTs)and graphene platelets(GPLs)in the 1990 and 2000s,the demand for high-performance structural applications and multifunctional materials has driven significant int... Since the initial observation of carbon nanotubes(CNTs)and graphene platelets(GPLs)in the 1990 and 2000s,the demand for high-performance structural applications and multifunctional materials has driven significant interest in composite structures reinforced with GPLs and CNTs.Incorporating these nanofillers into matrix materials markedly enhances the mechanical properties of the structures.To further improve efficiency and functionality,func-tionally graded(FG)distributions of CNTs and GPLs have been proposed.This study presents an extensive review of computational approaches developed to predict the global behavior of composite structural components enhanced with CNT and GPL nanofillers.The analysis focuses on key structural elements,such as plate-type configurations,cylindrical and curved shells,and beams,emphasizing the computational techniques utilized to simulate their mechanical behavior.The utilization of three-dimensional elasticity theories and equivalent single-layer(ESL)frameworks,which are widely employed in the modeling and analysis of these composites,is comprehensively discussed.Additionally,the paper examines various mechanical performance aspects,including static,buckling,post-buckling,vibrational,and dynamic responses for the mentioned structures.The unique features of hybrid nanocomposites,combining CNTs and GPLs,are also analyzed.Furthermore,the study delves into the fabrication and processing techniques of these materials,with a particular focus on strategies to mitigate nanofiller agglomeration.The review extends to cover thermal and electrical properties,durability under environmental exposure,fatigue resistance,and vibration-damping characteristics.In conclusion,the paper underscores the necessity for ongoing advancements in computational modeling to facilitate improved design,analysis,and optimization of nanocomposite structures.Future research opportunities in this rapidly advancing domain are also outlined. 展开更多
关键词 Graphene platelets carbon nanotubes functionally graded materials hybrid composites mechanical analyses PLATES SHELLS BEAMS
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Critical processes controlling the formation of visible gold in the giant Jiaodong gold province:Constraints from microtextural and geochemical analyses by SEM,TOF-SIMS,and LA-(MC)-ICP-MS
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作者 Hong Wang Ting-Guang Lan +6 位作者 Lang-Ye Zhao Hong-Rui Fan Zhan-Ping Li Huan-Long Hu Zi-Qi Xu Hong-Wei Peng Lei Shu 《Acta Geochimica》 2025年第6期1167-1185,共19页
The world-class Jiaodong gold province in the North China Craton hosts over 5000 t of Au resource and is characterized by abundant visible gold mineralization.However,the critical processes controlling the formation o... The world-class Jiaodong gold province in the North China Craton hosts over 5000 t of Au resource and is characterized by abundant visible gold mineralization.However,the critical processes controlling the formation of visible gold in this province remain poorly understood.To solve this problem,integrated microtextural,trace elemental,and sulfur isotopic analyses of pyrite from the high-grade Linglong gold deposit in the Jiaodong gold province were conducted in this study.Two distinct pyrite types were identified within auriferous quartz-sulfide veins:(1)Py1 aggregates in quartz-pyrite veins(hydrothermal stageⅡ),and(2)euhedral to subhedral,coarse-grained Py2 crystals in quartz-polymetallic sulfide veins(hydrothermal stageⅢ).Microtextural and elemental analyses revealed that visible gold predominantly occurs as intergranular particles between primary pyrite crystals within Py1 aggregates.The Py1 exhibits complex microtextures with abundant mineral inclusions of polymetallic sulfides and has low concentrations of Au(median:0.032 ppm)with a narrowδ^(34)S range(4.86‰-6.75‰),indicative of rapid crystallization under unstable,disequilibrium conditions.By contrast,the Py2 is texturally homogeneous and contains higher Au concentrations(median:0.304 ppm)with progressively increasingδ^(34)S values(5.25‰-10.14‰)over time,suggesting slow crystal growth under more stable,near-equilibrium conditions.Based on the microtextural and geochemical information,it is proposed that fluid boiling occurred only during the hydrothermal stage Ⅱ,which resulted in the unstable physicochemical environment and rapid deposition of gold.During the boiling processes,gold colloids likely occurred and promoted the formation of visible gold. 展开更多
关键词 Visible gold deposition PYRITE GEOCHEMISTRY Jiaodong gold province Microtextural analyses
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Verification and Validation for Large Eddy Simulation of Cavitating Flow Around a Projectile Near the Free Surface
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作者 Linfeng Deng Yun Long +1 位作者 Huaiyu Cheng Bin Ji 《哈尔滨工程大学学报(英文版)》 2025年第4期659-681,共23页
Verification and validation(V&V)is a helpful tool for evaluating simulation errors,but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an... Verification and validation(V&V)is a helpful tool for evaluating simulation errors,but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an asymptotic range.Hence,a new V&V approach for large eddy simulation(LES)is proposed.This approach offers a viable solution for the error estimation of simulation data that are unable to satisfy the asymptotic range.The simulation errors of cavitating flow around a projectile near the free surface are assessed using the new V&V method.The evident error values are primarily dispersed around the cavity region and free surface.The increasingly intense cavitating flow increases the error magnitudes.In addition,the modeling error magnitudes of the Dynamic Smagorinsky-Lilly model are substantially smaller than that of the Smagorinsky-Lilly model.The present V&V method can capture the decrease in the modeling errors due to model enhancements,further exhibiting its applicability in cavitating flow simulations.Moreover,the monitoring points where the simulation data are beyond the asymptotic range are primarily dispersed near the cavity region,and the number of such points grows as the cavitating flow intensifies.The simulation outcomes also suggest that the re-entrant jet and shedding cavity collapse are the chief sources of vorticity motions,which remarkably affect the simulation accuracy.The results of this study provide a valuable reference for V&V research. 展开更多
关键词 Cavitating flow Free surface Verification and validation Error analyses Asymptotic range
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Numerical study on reinforced vertical cuts integrated with RC buildings under the effects of ground motion
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作者 Amrita B.R.Jayalekshmi R.Shivashankar 《Earthquake Engineering and Engineering Vibration》 2025年第4期959-976,共18页
Soil nailing is an effective method used for stabilizing excavations and natural ground slopes.In situations with space constraints due to rapid urbanization,the available space near the soil-nailed vertical cuts can ... Soil nailing is an effective method used for stabilizing excavations and natural ground slopes.In situations with space constraints due to rapid urbanization,the available space near the soil-nailed vertical cuts can be utilized to construct multi-storied buildings.However,the presence of a building in proximity to the retained soil mass may alter the seismic response of a nailed structure.The building can be either constructed at a distance,connected or attached to the soil-nailed structure depending on the space availability.This study evaluates the behavior of such an integrated soil-nailed,wall-building system under seismic excitations by employing finite element analysis.The seismic response of a nailed wall supporting a vertical cut of a height of 6m under different connectivity conditions with an adjacent multi-story RC building is analyzed.Parametric studies are conducted with various heights of a building and under different frequency content of seismic excitations.The performance of the integrated system is evaluated regarding displacement and the acceleration response of the soil-nailed wall,as well as tensile force mobilized in nails.The innovative concept of integration between the two structures yields better seismic stability of the nailed structure,as well as for optimum use of land in space-constrained grounds with vertical cuts. 展开更多
关键词 integrated system soil-nailed wall finite element analyses seismic excitation
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Intrinsic mechanisms influencing the tensile fracture reliability of CuZr-based amorphous microwires
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作者 Shuang Su Chang-Yu Liu +6 位作者 Xin Su Yagnesh Shadangi Guan-Yu Cao Zhi-Liang Ning Jian-Fei Sun Yong-Jiang Huang Jürgen Eckert 《Rare Metals》 2025年第4期2682-2694,共13页
Amorphous microwires(AMWs)are well known for their high strength and elastic limit,making them excellent candidates for various engineering applications.However,one of the key challenges in utilizing AMWs is their inh... Amorphous microwires(AMWs)are well known for their high strength and elastic limit,making them excellent candidates for various engineering applications.However,one of the key challenges in utilizing AMWs is their inherent variability in mechanical performance,particularly in achieving stable fracture strength across different compositions.This study provides critical insights into the relationship between microstructure and mechanical behavior by investigating CuZr-based AMWs with varying compositions during quasi-static tensile fracture.Specifically,uniaxial tensile tests on Cu_(48)Zr_(48)Al_(4),Cu_(45)Zr_(45)Co_(10),and Cu_(48)Zr_(47.2)Al_(4)Nb_(0.8) AMWs,combined with log-normal and Weibull statistical analysis,revealed that Cu_(48)Zr_(47.2)Al4Nb_(0.8) exhibits the highest fracture reliability(mTr=3.97)and fracture threshold(σμTr=1307 MPa),while Cu_(48)Zr_(48)Al_(4) showed the lowest performance(m_(Tr)=3.08,σ_(μTr)=1085 MPa).Moreover,a standard power-law relationship exists between the characteristic size L of the fracture surface and the degree of order O was established,linking atomic mixing enthalpy and atomic radius to structural homogeneity and fracture behavior.This study provides an important perspective for optimizing AMW compositions to achieve higher fracture strength and improve the reliability for engineering applications. 展开更多
关键词 Amorphous microwires Statistical analyses Fracture reliability Atomic mixing enthalpy
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The nexus between the financial development and CO_(2) emissions:fresh evidence through time–frequency analyses
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作者 Faik Bilgili Erhan Muğaloğlu +3 位作者 Sevda Kuşkaya Javier Cifuentes‑Faura Kamran Khan Mohammed Alnour 《Financial Innovation》 2025年第1期1442-1463,共22页
Climate change and environmental degradation threaten the world and global economic conditions.As one of countries’most important economic components,the financial sector might be an effective tool for reducing and e... Climate change and environmental degradation threaten the world and global economic conditions.As one of countries’most important economic components,the financial sector might be an effective tool for reducing and even reversing environmental degradation.The financial sector can affect sustainability through its lending and investment practices.The sector can play a role in financing sustainable projects and businesses,helping reduce CO_(2) emissions.By aligning its financial objectives with environmental protection,the financial sector can support the transition to a more sustainable future by helping reduce environmental degradation’s negative impacts.This paper examines the domestic financial sector’s impact on CO_(2) emissions in the United States over the 1990:Q1–2022:Q3 period.In this research,the nexus between the domestic financial sector(total debt securities,loans,liabilities,and total financial assets)and Carbon dioxide emissions in the U.S.is investigated by Morlet wavelet analysis.Rest of the world:sector discrepancy transactions,rest of the world:debt securities and loans,gross domestic product,and the square of the gross domestic product,are control variables in the estimated models.Partial wavelet coherency analyses prove that the financial sector reduces CO_(2) emissions at the 5–8-year frequency band during different subsample periods.The financial sector’s instruments can be effective in struggling with climate change. 展开更多
关键词 Financial sector Sustainable development Time-frequency analysis Wavelet analyses The U.S.
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