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Lithium Isotope Analytical Methods and Implications for Rare-Metal Mineralization in Granite-Pegmatite Systems: An Overview

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Journal of Earth Science 2024年

作者： xiang-ying ye Bin Li Dong-Bo Tan Ke-Cheng Liu Zhi-Yong Zhu Hafiz Muhammad Siddique Yi-Lin Xiao Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring (Ministry of Education)， School of Geosciences and Info-physics， Central South University CAS Key Laboratory of Geospace Environment and Department of Plasma Physics and Fusion Engineering， University of Science and Technology of China Institute of Geology， Chinese Academy of Geological Sciences CAS Key Laboratory of Crust-Mantle Materials and Environments， School of Earth and Space Sciences， University of Science and Technology of China Chinese Academy of Sciences Center of Excellence in Comparative Planetology

The origin of highly-fractionated granite-pegmatite systems and their associated rare metal mineralization has been widely studied， but there is still ongoing debate. Prevailing hypotheses suggest that pegmatite formation and the associated rare metal mineralization are closely related to aqueous fluid processes. Lithium (Li) isotope analysis has been widely applied to trace granite-pegmatite evolution. This is because lithium is widely present in various minerals (e.g.， mica， tourmaline) that record the melt and fluid compositions， and lithium isotopes are sensitive to magmatic-hydrothermal processes. We briefly review the methodology of Li isotope analyses， the mechanisms of Li isotopic fractionation， and， in particular， Li isotope fractionation in granite-pegmatite system based on Li isotope data we have collected and the latest developments in Li isotope geochemistry. With the development of analytical technology， high-precision measurement of the Li content and isotopic compositions have facilitated a series of scientific breakthroughs in understanding the magmatic-hydrothermal evolution of rare-element ore deposits. Li isotope analysis on bulk mineral separates show ability to trace various hydrothermal processes (e.g. exotic or exsolved fluids). In situ Li isotope analysis methods has been enhanced by the development of new， homogeneous mineral reference materials. In situ SIMS and LA-MC-ICP-MS Li isotope measurements on minerals (e.g.， tourmaline) will likely become more important in studying the fluid–rock interactions in magmatic， metamorphic， and hydrothermal processes， as well as on pegmatite petrogenesis and rare-metal mineralization.

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The joint Laplace transforms for killed diffusion occupation times

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 398-415页

作者： LI ying-qiu CHEN ye School of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China College of Mathematics and Computational Science Hunan University of Arts and ScienceChangde 415000China

The approach of Li and Zhou(2014)is adopted to find the Laplace transform of occupation time over interval(0,a)and joint occupation times over semi-infinite intervals(-∞,a)and(b,∞)for a time-homogeneous diffusion pr... 详细信息

关键词： time-homogeneous diffusion process occupation time joint occupation time Laplace transform Brownian motion with drift

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Effect of low-degree astigmatism on the objective visual quality

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1086-1093页

作者： Ling-ying ye Shu-Feng Li Jing-Jing Zuo Jin Li Hui-xiang Ma National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal *** cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree *** was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality ***:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were *** increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),*** decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),*** the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were ***:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

关键词： low-degree astigmatism objective visual quality Optical Quality Analysis System

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Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing Guo Kai-xiang Di Lie-Hui Zhang Yu-Long Zhao Hui-ying Tang Rui-Han Zhang ye Tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

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Carbon-based nanomaterials cause toxicity by oxidative stress to the liver and brain in Sprague-Dawley rats

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Nuclear Science and Techniques 2024年第6期35卷 54-64页

作者： ying-ying Xu Chan Jin Meng Wu Jian-ye Zhou Hui-Ling Wei Department of Gastroenterology China-Japan Friendship HospitalBeijing 100029China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Institute of Particle and Nuclear Physics College of PhysicsHenan Normal UniversityXinxiang 453007China

Carbon-based nanomaterials have important research significance in various disciplines,such as composite materials,nanoelectronic devices,biosensors,biological imaging,and drug ***,the human and ecological risks associated with carbon-based nanomaterials have received increasing ***,the biological safety of carbon based nanomaterials has not been systematically *** this study,we used different types of carbon materials,namely,graphene oxide(GO),single-walled carbon nanotubes(SWCNTs),and multiwalled carbon nanotubes(MWCNTs),as models to observe their distribution and oxidative damage in *** results of Histopathological and ultrastructural examinations indicated that the liver and lungs were the main accumulation targets of these ***-μ-XRF analysis revealed that SWCNTs and MWCNTs might be present in the *** shows that the three types of carbon-based nanomaterials could cross the gas-blood barrier and eventually reach the liver *** addition,SWCNTs and MWCNTs could cross the blood-brain barrier and accumulate in the cerebral *** increase in ROS and MDA levels and the decrease in GSH,SOD,and CAT levels indicated that the three types of nanomaterials might cause oxidative stress in the *** suggests that direct instillation of these carbon-based nanomaterials into rats could induce ROS *** addition,iron(Fe)contaminants in these nanomaterials were a definite source of free ***,these nanomaterials did not cause obvious damage to the rat brain *** deposition of selenoprotein in the rat brain was found to be related to oxidative stress and Fe *** information may support the development of secure and reasonable applications of the studied carbon-based nanomaterials.

关键词： Carbon-based nanomaterials Oxidative stress Trace element distribution TEM SR-μ-XRF

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Influence of vibration on the lubrication effect of a splash-lubricated gearbox

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 324-339页

作者： Yi LIU Kailin ZHANG Shuai SHAO Hongxu xiang Zhijian ye State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

In this study,we investigate the effect of rail vibrations on the lubrication and efficiency of a splash-lubricated gearbox;specifically,the gearbox of a rail-transit vehicle.A high-fidelity 3D numerical model of the gearbox in a moving reference system is described,as well as computational fluid dynamics(CFD)simulations of the gearbox with different vibration *** effects of rotational speed,oil-immersion depth,and different oil-injection volume rates on lubrication and efficiency are *** propose a method of evaluating the internal lubrication condition of a splash-lubricated gearbox and quantitatively compare the effects of different operating parameters on lubrication and ***,our experiment to verify the feasibility of the simulation method is *** results show that with vibration,the churning loss and oil supply for the bearings are significantly higher than those under static *** addition,among different vibrational directions,lateral vibration has the greatest influence on the lubrication condition and efficiency of the *** the studied railway-vehicle gearbox,the best lubrication condition is achieved at a rotational speed of 1600 r/min and an oil-immersion depth of two times the tooth height(***).Rotational speed is the operating parameter that has the most significant effect on the lubrication and efficiencyofthegearbox.

关键词： Comprehensive lubrication evaluation Churning loss Moving reference system Splash lubrication Vibrational excitation Gearbox

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Meta-Auto-Decoder:a Meta-Learning-Based Reduced Order Model for Solving Parametric Partial Differential Equations

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1096-1130页

作者： Zhanhong ye xiang Huang Hongsheng Liu Bin Dong Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China School of Computer Science and Technology University of Science and Technology of ChinaHefei 230027AnhuiChina Central Software Institute Huawei Technologies Co.LtdHangzhou 310007ZhejiangChina Center for Machine Learning Research Peking UniversityBeijing 100871China

Many important problems in science and engineering require solving the so-called parametric partial differential equations(PDEs),i.e.,PDEs with different physical parameters,boundary conditions,shapes of computational domains,*** reduced order modeling techniques accelerate the solution of the parametric PDEs by projecting them onto a linear trial manifold constructed in the ofline *** methods often need a predefined mesh as well as a series of precomputed solution snapshots,and may struggle to balance between the efficiency and accuracy due to the limitation of the linear *** the nonlinear representation of neural networks(NNs),we propose the Meta-Auto-Decoder(MAD)to construct a nonlinear trial manifold,whose best possible performance is measured theoretically by the decoder *** on the meta-learning concept,the trial manifold can be learned in a mesh-free and unsupervised way during the pre-training *** adaptation to new(possibly heterogeneous)PDE parameters is enabled by searching on this trial manifold,and optionally fine-tuning the trial manifold at the same *** numerical experiments show that the MAD method exhibits a faster convergence speed without losing the accuracy than other deep learning-based methods.

关键词： Parametric partial differential equations(PDEs) Meta-learning Reduced order modeling Neural networks(NNs) Auto-decoder

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Preparation and Reinforcement Adaptability of Jute Fiber Reinforced Magnesium Phosphate Cement Based Composite Materials

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 999-1009页

作者：刘芯州郭远臣 WANG Rui xiang Kai WANG Xue ye Qing College of Civil Engineering Chongqing Three Gorges UniversityChongqing 404100China

To improve the brittleness characteristics of magnesium phosphate cement-based materials(MPC)and to promote its promotion and application in the field of structural reinforcement and repair,this study aimed to increase the toughness of MPC by adding jute fiber,explore the effects of different amounts of jute fiber on the working and mechanical properties of MPC,and prepare jute fiber reinforced magnesium phosphate cement-based materials(JFRMPC)to reinforce damaged *** improvement effect of beam performance before and after reinforcement was compared,and the strengthening and toughening mechanisms of jute fiber on MPC were explored through microscopic *** experimental results show that,as the content of jute fiber(JF)increases,the fluidity and setting time of MPC decrease continuously;When the content of jute fiber is 0.8%,the compressive strength,flexural strength,and bonding strength of MPC at 28 days reach their maximum values,which are increased by 18.0%,20.5%,and 22.6%compared to those of M0,*** beam strengthened with JFRMPC can withstand greater deformation,with a deflection of 2.3 times that of the unreinforced beam at *** strain of the steel bar is greatly reduced,and the initial crack and failure loads of the reinforced beam are increased by 192.1%and 16.1%,respectively,compared to those of the unreinforced *** JF added to the MPC matrix dissipates energy through tensile fracture and debonding pull-out,slowing down stress concentration and inhibiting the free development of cracks in the matrix,enabling JFRMPC to exhibit higher strength and better *** JF does not cause the hydration of MPC to generate new compounds but reduces the amount of hydration products generated.

关键词： magnesium phosphate cement jute fiber reinforcement of damaged beam flexural behavior

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Risk factors for the prognosis of colon cancer

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3738-3740页

作者： Chu-ying Wu Kai ye Department of Gastrointestinal Surgery The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina

A study on clinical outcomes and prognostic factors in T4N0M0 colon cancer patients after R0 resection revealed that ileostomy,T stage,right hemicolectomy,irregular follow-up,and CA199 level were independent risk factors affecting overall survival.T4-stage cancer invades the entire thickness of the intestinal tract,increasing the difficulty of treatment and the risk of recurrence,and requires a combination of chemotherapy,immunotherapy,and targeted therapy to control the spread of cancer *** prognosis of right hemicolectomy is significantly worse than that of left hemicolectomy,and right hemicolectomy is an independent risk factor for a poor *** age,histopathological type,and lymph node metastasis are also risk factors for colon cancer.

关键词： Risk factor Prognosis Colon cancer Tumour stage Right hemicolectomy

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Memory Trace for Fear Extinction:Fragile yet Reinforceable

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Neuroscience Bulletin 2024年第6期40卷 777-794页

作者： ying Liu Shuai ye Xin-Ni Li Wei-Guang Li Department of Rehabilitation Medicine State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceHuashan HospitalInstitute for Translational Brain ResearchFudan UniversityShanghai200032China

Fear extinction is a biological process in which learned fear behavior diminishes without anticipated reinforcement,allowing the organism to re-adapt to ever-changing *** on the behavioral hypothesis that extinction is new learning and forms an extinction memory,this new memory is more readily forgettable than the original fear *** brain’s cellular and synaptic traces underpinning this inherently fragile yet reinforceable extinction memory remain *** questions are about the whereabouts of the engram neurons that emerged during extinction learning and how they constitute a dynamically evolving functional construct that works in concert to store and express the extinction *** this review,we discuss recent advances in the engram circuits and their neural connectivity plasticity for fear extinction,aiming to establish a conceptual framework for understanding the dynamic competition between fear and extinction memories in adaptive control of conditioned fear responses.

关键词： Fear extinction memory Memory trace Fear relapse Medial prefrontal cortex Basolateral amygdala Ventral hippocampus Insular cortex Synaptic adaptations

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