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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders
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作者 Qing Qiu Mengting Yang +2 位作者 Danfeng Gong Haiying Liang Tingting Chen 《Neural Regeneration Research》 SCIE CAS 2025年第5期1258-1276,共19页
The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central n... The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be used to treat these disorders. We concluded that there are few clinical drugs that can improve the pathology these diseases by acting on potassium or calcium ions. Although a few novel ion-channelspecific modulators have been discovered, meaningful therapies have largely not yet been realized. The lack of target-specific drugs, their requirement to cross the blood–brain barrier, and their exact underlying mechanisms all need further attention. This review aims to explain the urgent problems that need research progress and provide comprehensive information aiming to arouse the research community's interest in the development of ion channel-targeting drugs and the identification of new therapeutic targets for that can increase the cure rate of nervous system diseases and reduce the occurrence of adverse reactions in other systems. 展开更多
关键词 ASTROCYTES calcium channels central nervous system extracellular ion concentration MICROGLIA neurological disorders NEURONS potassium channels
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Vedolizumab serum trough concentrations with and without thiopurines in ulcerative colitis: The prospective VIEWS pharmacokinetics study
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作者 Thanaboon Chaemsupaphan Aviv Pudipeddi +4 位作者 Hui-Yu Lin Sudarshan Paramsothy Viraj C Kariyawasam Melissa Kermeen Rupert W Leong 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期102-112,共11页
BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thio... BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thiopurines on vedolizumab trough concentrations is unknown.AIM To investigate the exposure-response relationship of vedolizumab and the impact of thiopurine withdrawal in UC patients who have achieved sustained clinical and endoscopic remission during maintenance therapy.METHODS This is a post-hoc analysis of prospective randomized clinical trial(VIEWS)involving UC patients across 8 centers in Australia from 2018 to 2022.Patients in clinical and endoscopic remission were randomized to continue or withdraw thiopurine while receiving vedolizumab.We evaluated vedolizumab serum trough concentrations,presence of anti-vedolizumab antibodies,and clinical outcomes over 48 weeks to assess exposure-response asso-ciation and impact of thiopurine withdrawal.RESULTS There were 62 UC participants with mean age of 43.4 years and 42%were females.All participants received vedolizumab as maintenance therapy with 67.7%withdrew thiopurine.Vedolizumab serum trough concentrations remained stable over 48 weeks regardless of thiopurine use,with no anti-vedolizumab antibodies detected.Pa-tients with clinical remission had higher trough concentrations at week 48.In quartile analysis,a threshold of>11.3μg/mL was associated with sustained clinical remission,showing a sensitivity of 82.4%,specificity of 60.0%,and an area of receiver operating characteristic of 0.71(95%CI:0.49-0.93).Patients discontinuing thiopurine required higher vedolizumab concentrations for achieving remission.CONCLUSION A positive exposure-response relationship between vedolizumab trough concentrations and UC outcomes suggests that monitoring drug levels may be beneficial.While thiopurine did not influence vedolizumab levels,its with-drawal may necessitate higher vedolizumab trough concentrations to maintain remission. 展开更多
关键词 PHARMACOKINETIC Vedolizumab THIOPURINE Ulcerative colitis Trough concentration Antibody Inflammatory bowel diseases
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Impact of Pollutant Concentration and Particle Deposition on the Radiative Flow of Casson-Micropolar Fluid between Parallel Plates
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作者 Ghaliah Alhamzi Badr Saad T.Alkahtani +2 位作者 Ravi Shanker Dubey Vinutha Kalleshachar Neelima Nizampatnam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期665-690,共26页
Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing po... Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters. 展开更多
关键词 Micropolar fluid thermal radiation porous medium thermophoretic particle deposition waste discharge concentration
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Charting the course to solid-state dual-ion batteries 被引量:1
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作者 Habtom D.Asfaw Antonia Kotronia +2 位作者 Nuria Garcia-Araez Kristina Edström Daniel Brandell 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期132-177,共46页
An electrolyte destined for use in a dual-ion battery(DIB)must be stable at the inherently high potential required for anion intercalation in the graphite electrode,while also protecting the Al current collector from ... An electrolyte destined for use in a dual-ion battery(DIB)must be stable at the inherently high potential required for anion intercalation in the graphite electrode,while also protecting the Al current collector from anodic dissolution.A higher salt concentration is needed in the electrolyte,in comparison to typical battery electrolytes,to maximize energy density,while ensuring acceptable ionic conductivity and operational safety.In recent years,studies have demonstrated that highly concentrated organic electrolytes,ionic liquids,gel polymer electrolytes(GPEs),ionogels,and water-in-salt electrolytes can potentially be used in DIBs.GPEs can help reduce the use of solvents and thus lead to a substantial change in the Coulombic efficiency,energy density,and long-term cycle life of DIBs.Furthermore,GPEs are suited to manufacture compact DIB designs without separators by virtue of their mechanical strength and electrical performance.In this review,we highlight the latest advances in the application of different electrolytes in DIBs,with particular emphasis on GPEs. 展开更多
关键词 anion intercalation concentrated electrolytes dual-ion battery graphite ionic liquids polymer electrolyte
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Dynamics and genetic regulation of macronutrient concentrations during grain development in maize 被引量:1
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作者 Pengcheng Li Shuangyi Yin +7 位作者 Yunyun Wang Tianze Zhu Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Chenwu Xu Zefeng Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期781-794,共14页
Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics an... Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown. In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination. We then calculated conditional phenotypic values at different time intervals to explore the dynamic characteristics of the N, P, and K concentrations. Abundant phenotypic variations were observed in the concentrations and net changes of these nutrients. Unconditional quantitative trait locus(QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for the N, P, and K concentrations, respectively. Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in the N, P, and K concentrations. By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for the N, P, and K concentrations, respectively, including GRMZM2G371058 encoding a Doftype zinc finger DNA-binding family protein, which was associated with the N concentration, and GRMZM2G113967encoding a CBL-interacting protein kinase, which was related to the K concentration. The results deepen our understanding of the genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for the genetic improvement of nutrient concentrations in maize. 展开更多
关键词 MAIZE nutrient concentration unconditional QTL mapping conditional QTL mapping dynamic trait
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Rheological properties and concentration evolution of thickened tailings under the coupling effect of compression and shear 被引量:1
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作者 Aixiang Wu Zhenqi Wang +3 位作者 Zhuen Ruan Raimund Bürger Shaoyong Wang Yi Mo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期862-876,共15页
Cemented paste backfill(CPB)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPB technology.However,difficult flocculation and substandard concentrations o... Cemented paste backfill(CPB)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPB technology.However,difficult flocculation and substandard concentrations of thickened tailings often occur.The rheological properties and concentration evolution in the thickened tailings remain unclear.Moreover,traditional indoor thickening experiments have yet to quantitatively characterize their rheological properties.An experiment of flocculation condition optimization based on the Box-Behnken design(BBD)was performed in the study,and the two response values were investigated:concentration and the mean weighted chord length(MWCL)of flocs.Thus,optimal flocculation conditions were obtained.In addition,the rheological properties and concentration evolution of different flocculant dosages and ultrafine tailing contents under shear,compression,and compression-shear coupling experimental conditions were tested and compared.The results show that the shear yield stress under compression and compression-shear coupling increases with the growth of compressive yield stress,while the shear yield stress increases slightly under shear.The order of shear yield stress from low to high under different thickening conditions is shear,compression,and compression-shear coupling.Under compression and compression-shear coupling,the concentration first rapidly increases with the growth of compressive yield stress and then slowly increases,while concentration increases slightly under shear.The order of concentration from low to high under different thickening conditions is shear,compression,and compression-shear coupling.Finally,the evolution mechanism of the flocs and drainage channels during the thickening of the thickened tailings under different experimental conditions was revealed. 展开更多
关键词 thickened tailings compression-shear coupling compressive yield stress shear yield stress CONCENTRATION
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Trends of surface ozone based on hourly concentrations in the Beijing–Tianjin–Hebei region during 2017–2021 被引量:1
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作者 Xiaoyan Wang Huihui Zheng +3 位作者 Bing Liu Shuyan Xie Yonghai Huang Shuai Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期26-32,共7页
As a typical secondary air pollutant,surface ozone has been monitored routinely since 2013 in China.Most studies on the spatiotemporal variation of ozone have been centered around the daily maximum 8-h average,with li... As a typical secondary air pollutant,surface ozone has been monitored routinely since 2013 in China.Most studies on the spatiotemporal variation of ozone have been centered around the daily maximum 8-h average,with little attention paid to the trends of hourly ozone,especially hourly ozone exceedances.Focusing on hourly ozone exceedances and peak values,the spatiotemporal trends of hourly ozone at 77 sites in 13 cities of the Beijing-Tianjin-Hebei(BTH)region during 2017-2021 were analyzed in this study.The number of hours with exceedances(N_(H200))in 2019 was nearly three times that of 2021.On a five-year average,the percentage of cumulative NH200 in June accounted for up to 40.5%of all hourly exceedances.Cities in central Hebei Province had the highest cumulative annual N_(H200).June had the highest average hourly ozone exceeded multiples of 0.158.The top two cities with the highest average exceeded multiple were Tangshan(0.166)and Beijing(0.158).Tangshan and Xingtai ranked as the top two in terms of the mean of the 10 highest daily maximum ozone concentrations(MTDM),with 286.74 and 285.37μg m^(−3),respectively.The gap between the MTDM and the daily maximum of hourly ozone averaged over all sites had narrowed to 97.88μg m^(−3) in 2021,much lower than that in other years,which indicated that the stability and convergence of ozone pollution in BTH region had been enhanced in 2021 to some extent. 展开更多
关键词 Surface ozone Hourly concentration Ozone exceedance Peak value Beijing-tianjin-hebei region
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A Facile Li_(2)TiO_(3) Surface Modification to Improve the Structure Stability and Electrochemical Performance of Full Concentration Gradient Li-Rich Oxides 被引量:1
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作者 Naifang Hu Yuan Yang +5 位作者 Lin Li Yuhan Zhang Zhiwei Hu Lan Zhang Jun Ma Guanglei Cui 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期41-48,共8页
Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rat... Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rate performance,whereas the high lithium residues on its surface impairs the structure stability and long-term cycle performance.Herein,a facile multifunctional surface modification method is implemented to eliminate surface lithium residues of full concentration gradient lithium-rich layered oxides by a wet chemistry reaction with tetrabutyl titanate and the post-annealing process.It realizes not only a stable Li_(2)TiO_(3)coating layer with 3D diffusion channels for fast Li^(+)ions transfer,but also dopes partial Ti^(4+)ions into the sub-surface region of full concentration gradient lithium-rich layered oxides to further strengthen its crystal structure.Consequently,the modified full concentration gradient lithium-rich layered oxides exhibit improved structure stability,elevated thermal stability with decomposition temperature from 289.57℃to 321.72℃,and enhanced cycle performance(205.1 mAh g^(-1)after 150 cycles)with slowed voltage drop(1.67 mV per cycle).This work proposes a facile and integrated modification method to enhance the comprehensive performance of full concentration gradient lithium-rich layered oxides,which can facilitate its practical application for developing higher energy density lithium-ion batteries. 展开更多
关键词 full concentration gradient lithium-rich layered oxides structure stability surface modification
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Efficient desorption and reuse of collector from the flotation concentrate:A case study of scheelite
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作者 Liming Tao Jianjun Wang +6 位作者 Dejin Liao Wenkai Jia Zihan Zhao Wenfang Che Zhongxu Qi Wei Sun Zhiyong Gao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第11期2435-2444,共10页
Flotation is the most common method to obtain concentrate through the selective adsorption of collectors on target minerals to make them hydrophobic and floatable.In the hydrometallurgy of concentrate,collectors adsor... Flotation is the most common method to obtain concentrate through the selective adsorption of collectors on target minerals to make them hydrophobic and floatable.In the hydrometallurgy of concentrate,collectors adsorbed on concentrate can damage ion-exchange resin and increase the chemical oxygen demand(COD)value of wastewater.In this work,we proposed a new scheme,i.e.,desorbing the collectors from concentrate in ore dressing plant and reusing them in flotation flowsheet.Lead nitrate and benzohydroxamic acid(Pb-BHA)complex is a common collector in scheelite flotation.In this study,different physical(stirring or ultrasonic waves)and chemical(strong acid or alkali environment)methods for facilitating the desorption of Pb-BHA collector from scheelite concentrate were explored.Single-mineral desorption tests showed that under the condition of pulp pH 13 and ultrasonic treatment for 15 min,the highest desorption rates of Pb and BHA from the scheelite concentrate were 90.48%and 63.75%,respectively.Run-of-mine ore flotation tests revealed that the reuse of desorbed Pb and BHA reduced the collector dosage by 30%for BHA and 25%for Pb.The strong alkali environment broke the chemical bonds between Pb and BHA.The cavitation effect of ultrasonic waves effectively reduced the interaction intensity between Pb-BHA collector and scheelite surfaces.This method combining ultrasonic waves and strong alkali environment can effectively desorb the collectors from concentrate and provide“clean”scheelite concentrate for metallurgic plants;the reuse of desorbed collector in flotation flowsheet can reduce reagent cost for ore dressing plants. 展开更多
关键词 scheelite concentrate COLLECTOR DESORPTION REUSE FLOTATION
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Features of rare earth elements geochemistry in coals of Central Kazakhstan
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作者 Aiman Nygmetovna Kopobayeva Altynay Amangeldikyzy +1 位作者 Gulim Galymzhanovna Blyalova Nazym Srajadinkyzy Askarova 《Acta Geochimica》 EI CAS CSCD 2024年第5期876-888,共13页
This research presents the results of a comprehensive study of mineralogical and geochemical features of REE distribution in coals of Central Kazakhstan deposits—Karaganda coal basin and Shubarkol deposit,which have ... This research presents the results of a comprehensive study of mineralogical and geochemical features of REE distribution in coals of Central Kazakhstan deposits—Karaganda coal basin and Shubarkol deposit,which have large hard coal reserves and are industrially important for the coal industry of Kazakhstan;the research is based on 205 samples of clayey interlayers and coal seams.It shows basic patterns of distribution and features of concentration for impurity elements,gives an estimate of the impurity elements concentration,including REE,defines conditions and factors of their accumulation,and studies features of their forms in coal and coal-bearing rocks,which allows estimating the mechanisms of their migration and conditions of accumulation.According to the results of geochemical indicators,the article establishes the factors of REE dislocation,reveals the composition of margin rocks that have influenced REE concentration in coal seams,and the presented latest data on mineralogy allowed to establish the ways of their transportation to the paleobasin during the synand epigenetic periods of formation of the coal deposits of Central Kazakhstan being researched.It was found that the coals are insignificantly enriched with heavy lanthanides from Ho to Lu.The distribution curves of UCC normalized REE values in the coals are similar and coincide,but they are less than the average value for world coal,and amount to only one-third of the UCC.It was found that the highest concentrations of all REE are characteristic of clayey interlayers and oxidized coals.The La/Yb ratio in this case increases upwards along the section,indicating mainly clastogenic mechanism of REE delivery to the coals.In coal and clay samples,the predominant mineral form of REE is light lanthanide phosphates.Identified particles of REE from minerals and their composition peculiarities suppose autigene nature of their formation.The formation of the bulk of autigene minerals occurred during the maturation of brown coals and their transformation into hard ones. 展开更多
关键词 Coal REE Impurity elements Accumulation conditions Concentration factors
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Failure Analysis of Dissimilar Metal Welds between Ferritic Heat Resistant Steels and Austenitic Stainless Steels in Power Plant
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作者 Xiaogang Li Junfeng Nie +2 位作者 Xin Wang Kejian Li Haiquan Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期306-326,共21页
This study analysed the failure of dissimilar metal welds(DMWs)between ferritic heat resistant steels and austenitic stainless steels and investigated its influencing factors by means of numerical simulation,microstru... This study analysed the failure of dissimilar metal welds(DMWs)between ferritic heat resistant steels and austenitic stainless steels and investigated its influencing factors by means of numerical simulation,microstructure characterization and mechanical property test.Under the long-term high-temperature service condition in practical power plant,the DMW failure mode was along the interface between nickel-based weld metal(WM)and ferritic heat resistant steel,and the failure mechanism was stress/strain concentration,microstructure degradation and oxidation coupling acting on the interface.The numerical simulation results show that interface stress/strain concentration was due to the differences in coefficient of thermal expansion and creep strength,and the degree of stress/strain concentration was related to service time.The ferrite band formed at the WM/ferritic steel interface was prone to cracking,attracting the fracture along the interface.The interface crack allowed oxidation to develop along the WM/ferritic steel interface.During long-term service,the interface stress/strain concentration,microstructure and oxidation all evolved,which synergistically promoted interface failure of DMW.However,only under the long-term service of low stress conditions could trigger the interface failure of DMW.Meanwhile,long-term service would reduce the mechanical strength and plasticity of DMW. 展开更多
关键词 Dissimilar metal weld FAILURE INTERFACE Stress/strain concentration MICROSTRUCTURE OXIDATION
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Achievable hole concentration at room temperature as a function of Mg concentration for MOCVD-grown p-GaN after sufficient annealing
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作者 Siyi Huang Masao Ikeda +4 位作者 Feng Zhang Minglong Zhang Jianjun Zhu Shuming Zhang Jianping Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期67-73,共7页
Relationship between the hole concentration at room temperature and the Mg doping concentration in p-GaN grown by MOCVD after sufficient annealing was studied in this paper.Different annealing conditions were applied ... Relationship between the hole concentration at room temperature and the Mg doping concentration in p-GaN grown by MOCVD after sufficient annealing was studied in this paper.Different annealing conditions were applied to obtain sufficient activation for p-GaN samples with different Mg doping ranges.Hole concentration,resistivity and mobility were characterized by room-temperature Hall measurements.The Mg doping concentration and the residual impurities such as H,C,O and Si were measured by secondary ion mass spectroscopy,confirming negligible compensations by the impurities.The hole concentration,resistivity and mobility data are presented as a function of Mg concentration,and are compared with literature data.The appropriate curve relating the Mg doping concentration to the hole concentration is derived using a charge neutrality equation and the ionized-acceptor-density[N-(A)^(-)](cm^(−3))dependent ionization energy of Mg acceptor was determined asE_(A)^(Mg)=184−2.66×10^(−5)×[N_(A)^(-)]1/3 meV. 展开更多
关键词 P-GAN hole concentration electrical properties ANNEALING ionization energy
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Suppressed concentration quenching and tunable photoluminescence in Eu^(2+)-activated Rb_(3)Y(PO_(4))_(2)phosphors for full-spectrum lighting
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作者 Ming Zhao Yeping Ge +3 位作者 Yurong Li Xiaoyan Song Zhiguo Xia Xinping Zhang 《Light(Science & Applications)》 SCIE EI CSCD 2024年第11期2688-2698,共11页
Highly efficient inorganic phosphors are desirable for lighting-emitting diode light sources,and increasing the doping concentration of activators is a common approach for enhancing the photoluminescence quantum yield... Highly efficient inorganic phosphors are desirable for lighting-emitting diode light sources,and increasing the doping concentration of activators is a common approach for enhancing the photoluminescence quantum yield(PLQY).However,the constraint of concentration quenching poses a great challenge for improving the PLQY.Herein,we propose a fundamental design principle by separating activators and prolonging their distance in Eu^(2+)-activated Rb_(3)Y(PO_(4))_(2)phosphors to inhibit concentration quenching,in which different quenching rates are controlled by the Eu distribution at various crystallographic sites.The blue-violet-emitting Rb_(3)Y(PO_(4))2:xEu(x=0.1%–15%)phosphors,with the occupation of Rb1,Rb2 and Y sites by Eu^(2+),exhibit rapid luminescence quenching with optimum external PLQY of 10%due to multi-channel energy migration.Interestingly,as the Eu concentration increases above 20%,Eu^(2+)prefer to occupy the Rb1 and Y sites with separated polyhedra and large interionic distances,resulting in green emission with suppressed concentration quenching,achieving an improved external PLQY of 41%.Our study provides a unique design perspective for elevating the efficiency of Eu^(2+)-activated phosphors toward high-performance inorganic luminescent materials for full-spectrum lighting. 展开更多
关键词 QUENCHING LIGHTING concentration
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New process for treating boron-bearing iron ore by flash reduction coupled with magnetic separation
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作者 Qipeng Bao Lei Guo +4 位作者 Hong Yong Sohn Haibin Zuo Feng Liu Yongliang Gao Zhancheng Guo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期473-484,共12页
Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional beneficiation.Th... Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional beneficiation.This study proposed a new treatment called flash reduction-melting separation(FRMS)for boron-bearing iron concentrates.In this method,the concentrates were first flash-reduced at the temperature under which the particles melt,and the slag and the reduced iron phases disengaged at the particle scale.Good reduc-tion and melting effects were achieved above 1550℃.The B_(2)O_(3) content in the separated slag was over 18wt%,and the B content in the iron was less than 0.03wt%.The proposed FRMS method was tested to investigate the effects of factors such as ore particle size and tem-perature on the reduction and melting steps with and without pre-reducing the raw concentrate.The mineral phase transformation and morphology evolution in the ore particles during FRMS were also comprehensively analyzed. 展开更多
关键词 LUDWIGITE boron-bearing iron concentrate flash reduction melting separation BORON
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Solar fuel production through concentrating light irradiation
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作者 Yiwei Fu Yi Wang +2 位作者 Jie Huang Kejian Lu Maochang Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第10期1550-1580,共31页
The climate crisis necessitates the development of non-fossil energy sources.Harnessing solar energy for fuel production shows promise and offers the potential to utilize existing energy infrastructure.However,solar f... The climate crisis necessitates the development of non-fossil energy sources.Harnessing solar energy for fuel production shows promise and offers the potential to utilize existing energy infrastructure.However,solar fuel production is in its early stages of development,constrained by low conversion efficiency and challenges in scaling up production.Concentrated solar energy(CSE)technology has matured alongside the rapid growth of solar thermal power plants.This review provides an overview of current CSE methods and solar fuel production,analyzes their integration compatibility,and delves into the theoretical mechanisms by which CSE impacts solar energy conversion efficiency and product selectivity in the context of photo-electrochemistry,thermochemistry,and photo-thermal co-catalysis for solar fuel production.The review also summarizes approaches to studying the photoelectric and photothermal effects of CSE.Lastly,it explores emerging novel CSE technology methods in the field of solar fuel production. 展开更多
关键词 Concentrated solar energy Solar fuel Photo-electrochemistry THERMOCHEMISTRY Photo-thermal co-catalysis
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Long-term operation optimization of circulating cooling water systems under fouling conditions
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作者 Jiarui Liang Yong Tian +3 位作者 Shutong Yang Yong Wang Ruiqi Yin Yufei Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期255-267,共13页
Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optim... Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization. 展开更多
关键词 Computer simulation Circulating water system FOULING Concentration cycle OPTIMIZATION Variable frequency drive
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MINIMIZERS OF L^(2)-SUBCRITICAL VARIATIONAL PROBLEMS WITH SPATIALLY DECAYING NONLINEARITIES IN BOUNDED DOMAINS
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作者 陈彬 高永帅 +1 位作者 郭玉劲 吴越 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期984-996,共13页
This paper is concerned with the minimizers of L^(2)-subcritical constraint variar tional problems with spatially decaying nonlinearities in a bounded domain Ω of R~N(N≥1).We prove that the problem admits minimizers... This paper is concerned with the minimizers of L^(2)-subcritical constraint variar tional problems with spatially decaying nonlinearities in a bounded domain Ω of R~N(N≥1).We prove that the problem admits minimizers for any M> 0.Moreover,the limiting behavior of minimizers as M→∞ is also analyzed rigorously. 展开更多
关键词 decaying nonlinearity L~2-subcritical MINIMIZERS bounded domains mass concentration
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Physical mechanism of secondary-electron emission in Si wafers
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作者 赵亚楠 孟祥兆 +5 位作者 彭淑婷 苗光辉 高玉强 彭斌 崔万照 胡忠强 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期677-681,共5页
CMOS-compatible RF/microwave devices,such as filters and amplifiers,have been widely used in wireless communication systems.However,secondary-electron emission phenomena often occur in RF/microwave devices based on si... CMOS-compatible RF/microwave devices,such as filters and amplifiers,have been widely used in wireless communication systems.However,secondary-electron emission phenomena often occur in RF/microwave devices based on silicon(Si)wafers,especially in the high-frequency range.In this paper,we have studied the major factors that influence the secondary-electron yield(SEY)in commercial Si wafers with different doping concentrations.We show that the SEY is suppressed as the doping concentration increases,corresponding to a relatively short effective escape depthλ.Meanwhile,the reduced narrow band gap is beneficial in suppressing the SEY,in which the absence of a shallow energy band below the conduction band will easily capture electrons,as revealed by first-principles calculations.Thus,the new physical mechanism combined with the effective escape depth and band gap can provide useful guidance for the design of integrated RF/microwave devices based on Si wafers. 展开更多
关键词 secondary-electron yield doping concentration escape depth Si wafer
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Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China
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作者 ZHANG Shouchuan LIU Kai +2 位作者 MA Yan WANG Luyao SUN Junliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期468-476,共9页
Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas an... Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District. 展开更多
关键词 fluoride concentration nitrate pollution genetic mechanism health risk assessment Tongzhou District
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The tri-band high spectral resolution spectrometer with gratings in tandem for the charge-exchange recombination spectroscopy diagnostic system on HL-2A tokamak
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作者 刘亮 余德良 +11 位作者 马倩 何小斐 Maarten DE BOCK Manfred von HELLERMANN Michael WALSH 陈文锦 何小雪 魏彦玲 张能 李栋 魏会领 the HL-2A Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期103-110,共8页
Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high s... Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high spectral resolution spectrometer has been developed for the charge-exchange recombination spectroscopy measurement on the HL-2A tokamak. The simultaneous measurements of He II(468.57 nm), C VI(529.1 nm), and Dα(656.1 nm accompanied by beam emission spectra) with an acquisition frequency up to 400 Hz are achieved by vertically binning the spectrum from each fiber in experiments. Initial results indicate that the system can provide radial profiles of not only ion temperature and rotation velocity,but also concentration of carbon. For the case of helium, the measurements for the ion temperature and rotation velocity are straightforward but the apparent concentration associated with the observed CX intensity is obviously too high. Modeling of the active He II CX feature including plume contributions needs to be carried out to extract the true helium concentration.The spectrometer could become a prototype for the ITER charge-exchange recombination spectroscopy diagnostic and the pilot experiments, as presented here, demonstrate the possibility of impurity concentrations measurements based on the combined measurement of local beam emission and charge-exchange recombination spectroscopy spectra. 展开更多
关键词 CXRS ion temperature plasma rotation impurity concentration
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