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Upper-rim-modified thioether thiacalix[4]arene used for liquid-liquid extraction of au(Ⅲ)and Pd(Ⅱ)in hydrochloric acid medium

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Chinese Journal of Chemical Engineering 2024年第2期66卷 110-118页

作者： Sheng Wan Rong Xie Jianhong Fan Kewen tang Department of Chemistry and Chemical Engineering Hunan Institute of Science and TechnologyYueyang 414006China

Gold(au)and palladium(Pd)play an increasing role in the production and human life;Therefore,it is of great significance to study their recovery.A 5,11,17,23-tetra-ethylthio-25,26,27,28-tetra-hydroxyl thiacalix[4]arene(TCAET)was synthesized specifically for the capture of au(Ⅲ)and Pd(Ⅱ)from HCl medium by liquid-liquid *** a 0.1 mol·L^(-1)HCl medium,the transfer of au(Ⅲ)and Pd(Ⅱ)from the aqueous phase to the organic phase was highly efficient,with a transfer ratio of 100%for au(Ⅲ)and 98%for Pd(Ⅱ).Furthermore,the extraction equilibrium time for au(Ⅲ)was just 5 ***'s method data demonstrated that TCAET formed complexes with au(Ⅲ)and Pd(Ⅱ)in a ratio of 2:3 and 1:1,respectively,during the extraction *** showed high selectivity toward Pd(Ⅱ)and au(Ⅲ)over other competing metal ***,both au(Ⅲ)and Pd(Ⅱ)could be successfully stripped from the loaded organic phases with a 1.0 mol·L^(-1)thiourea in 0.5 mol·L^(-1)HCl and 0.5 mol·L^(-1)thiourea in 0.5 mol·L^(-1)HCl,*** obtained from five consecutive extraction-stripping cycles showed good reusability of TCAET toward au(Ⅲ)and Pd(Ⅱ)*** conclusion can provide a certain reference for thiacalixarene in the recovery of precious metal species.

关键词： Thiacalixarene Upper-rim modification Liquid-liquid extraction Precious metal Thioether

Theoretical study on magnetocaloric effect and its electric-field regulation in CrI_(3)/metal heterostructure

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 134-141页

作者： Weiwei He Ziming tang Qihua Gong Min Yi Wanlin Guo State Key Laboratory of Mechanics and Control for Aerospace Structures Key Laboratory for Intelligent Nano Materials and Devices of Ministry of EducationInstitute for Frontier ScienceNanjing University of Aeronautics and AstronauticsNanjing 210016China MIIT Key Laboratory of Aerospace Information Materials and Physics College of PhysicsNanjing University of Aeronautics and AstronauticsNanjing 211106China

The extraordinary properties of a heterostructure by stacking atom-thick van der Waals(vdW)magnets have been extensively ***,the magnetocaloric effect(MCE)of heterostructures that are based on monolayer magnets remains to be ***,we deliberate MCE of vd W heterostructure composed of a monolayer CrI_(3)and metal atomic layers(Ag,Hf,au,and Pb).It is revealed that heterostructure engineering by introducing metal substrate can improve MCE of CrI_(3),particularly boosting relative cooling power to 471.72μJ m^(-2)and adiabatic temperature change to 2.1 K at 5 T for CrI_(3)/*** improved MCE is ascribed to the enhancement of magnetic moment and intralayer exchange coupling in CrI_(3)due to the CrI_(3)/metal heterointerface induced charge *** field is further found to tune MCE of CrI_(3)in heterostructures and could shift the peak temperature by around 10 K in CrI_(3)/Hf,thus manipulating the working temperature window of *** theoretical results could enrich the research on low-dimensional magnetocaloric materials.

关键词： magnetocaloric effect heterostructure metal substrate

Origin of the Yueguang gold deposit in Xinhua, Hunan Province, South China: insights from fl uid inclusion and hydrogen–oxygen stable isotope analysis

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Acta Geochimica 2024年第2期43卷 235-254页

作者： Hongxin Fan Qiang Wang Yulong Yang Yao tang Hao Zou College of Earth Sciences Chengdu University of TechnologyChengdu 610059China College of Earth Sciences Jilin UniversityJilin 130061China

The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South *** represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,west of the Baimashan granitic *** order to discern the characteristics of the ore-formingﬂuids,the underlying mineralization processes,and establish a foundation for the origin of the Yueguang gold depositﬂuid inclusion micro-thermometry,as well as quartz hydrogen and oxygen isotope analysis,have been carried out on samples obtained from various stages of *** hydrothermal miner-alization stages within the Yueguang gold deposit can be categorized into three stages:(i)the barren,pre-ore quartz-pyrite stage(Stage Ⅰ),the quartz-pyrite-gold stage(Stage Ⅱ),and the post-ore quartz-carbonate stage(Stage Ⅲ),with the second stage being the main mineralization ***ﬂuid inclusions identiﬁed in samples from the main min-eralization stage can predominantly be described with the NaCl–H_(2)O and CO_(2)–NaCl–H_(2)O *** inclusions display homogenization temperatures ranging from 158.8 to 334.9℃,and theﬂuid salinity ranges from 0.3%to 4.0%(wt.%NaCl equiv.).Laser Raman spectroscopy analysis of individual inclusions further reveals the presence of gas-phases such as CO_(2),CH_(4),and N_(2).Isotopic analysis indicatesδ^(18)Oﬂuid values ranging from 3.95 to 6.7‰ and δDH_(2)O values ranging from-71.9 to-55.7‰.These results indi-cate that the ore-formingﬂuid of the Yueguang gold deposit belongs to metamorphic hydrothermalﬂuids of middle-low temperature and low *** the process of ore formation,gold is transported in the form of au(HS)2-complexes,with gold deposition being driven byﬂuid ***,the Yueguang gold deposit is categorized as an orogenic gold deposit dominated by metamorphic hydrother-malﬂ*** may become a new target for gold exploration in the Baimashan region,central Hunan Province.

关键词： Hunan province Yueguang gold deposit Fluid inclusions Hydrogen–oxygen isotopes Laser Raman Fluid immiscibility Orogenic gold deposit

Pearls of meta-analyses and systematic review in scientific evidence

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World Journal of Clinical Cases 2024年第16期12卷 2701-2703页

作者： Sunny Chi Lik au Department of Ophthalmology Tung Wah Eastern HospitalHong KongChina

Scientific evidence develops bit by bit from case reports,case series;to larger casecontrol,case-cohort;and further escalate to randomized controlled *** echoed the importance of continue publishing World journal of Clinical Cases,where novel and advancing discoveries start from a single *** contrast,at the other end of the realm of evidence synthesis,systematic review and meta-analysis represent distinct yet interconnected *** in epidural labor analgesia has long been studied since 1989,and with 70 publications from MEDLINE ***,there was no meta-analysis,nor any systematic review published so *** latest in-press article published by tang et *** the protocol for the systematic review and meta-analysis on the safety and effectiveness of butorphanol in epidural labor analgesia is *** believe the findings of this study will be valuable for clinical practice as well as for future research.

关键词： Meta-analysis Systematic review Methodology Research Journal Academic

Single Particle Colorimetric Acid Phosphatase Activity Assay with CeO_(2)-modified Gold Nanoparticles

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Chemical Research in Chinese Universities 2024年第2期40卷 320-325页

作者： ZHU tang Jiayao YUAN Xiang MAO Guojiang WEI Lin XIAO Lehui Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research National and Local Joint Engineering Laboratory for New Petrochemical Materials and Fine Utilization of ResourcesCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha410081P.R.China Henan Key Laboratory of Organic Functional Molecule and Drug Innovation Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang453007P.R.China College of Chemistry and Chemical Engineering Central South UniversityChangsha410083P.R.China

Acid phosphatase(ACP)is a ubiquitous phosphatase in living *** abnormal variation of ACP is related to various ***,we propose a colorimetric method based on CeO_(2)-modified gold core shell nanoparticles(au@CeO_(2)NPs)to analyze ACP activity with high sensitivity and *** this design,2-phospho-L-ascorbic acid trisodium salt(AAP)is dephosphorylated by ACP and produces reductive ascorbic acid(AA),which makes the CeO_(2)shell decomposition.A remarkable blue shift of localized surface plasmon resonance peak(LSPR,from yellow to green)along with the scattering intensity ratio changes from individual au@CeO_(2)NPs are *** activity can be quantified by calculating the ratio changes of individual au@CeO_(2)*** assay reveals limit of detection(LOD)of 0.044 mU/mL and the linear range of 0.05–5.0 mU/mL,which are much lower than most of spectroscopic measurements in bulk ***,the recovery measurements in real samples are satisfactory and the capacity for practical application is *** a consequence,au@CeO_(2)NPs used in this assay will find new applications for the ultrasensitive detection of enzyme activity.

关键词： Single particle imaging Dark field Gold nanoparticle Enzyme activity Colorimetric detection

Methane oxybromination over Rh-based catalysts:Effect of supports

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Chinese Journal of Chemical Engineering 2020年第7期28卷 1809-1815页

作者： Peng Wang Lang Chen Sheng Shen chak-Tong au Shuangfeng Yin State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan Provincial Key Laboratory for Cost-effective Utilization of Fossil Fuel Aimed at Reducing Carbon-dioxide EmissionsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China College of Chemistry and Chemical Engineering Hunan Institute of EngineeringXiangtan 411104China.

Bromine mediation has been regarded as one of the most efficient ways to activate and convert methane to useful *** article reports the effects of active components(Rh,Ru,Pd and Pt)and supports(SiO2,Mg O and Al2O3)on the catalysis of methane *** the prepared catalysts,Rh/SiO2 is the best in performance(CH4 conversion of ca.20%and CH3Br selectivity exceeding 70%).The results reveal that support type has a notable influence on the catalytic performance of Rh,especially on product *** high selectivity to CH3 Br over Rh/SiO2 is attributed to its low propensity for CH3Br *** was found that Rh small in particle size shows high catalytic activity and CH3Br *** silicalite-1 zeolite suffers from a certain degree of structural damage due to the presence of high temperature steam,the use of silicalite-1 as support results in a performance comparable to that of Rh/SiO2.

关键词： Methane conversion Oxybromination Methyl bromide Rhodium catalyst

Application of artificial synapse based on all-inorganic perovskite memristor in neuromorphic computing

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Nano Materials Science 2024年第1期6卷 68-76页

作者： Fang Luo Wen-Min Zhong Xin-Gui tang Jia-Ying Chen Yan-Ping Jiang Qiu-Xiang Liu School of Physics&Optoelectric Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou510006China

Artificial synapse inspired by the biological brain has great potential in the field of neuromorphic computing and artificial *** memristor is an ideal artificial synaptic device with fast operation and good ***,we have prepared a memristor device with au/CsPbBr_(3)/ITO *** memristor device exhibits resistance switching behavior,the high and low resistance states no obvious decline after 400 switching *** memristor device is stimulated by voltage pulses to simulate biological synaptic plasticity,such as long-term potentiation,long-term depression,pair-pulse facilitation,short-term depression,and short-term *** transformation from short-term memory to long-term memory is achieved by changing the stimulation *** addition,a convolutional neural network was constructed to train/recognize MNIST handwritten data sets;a distinguished recognition accuracy of~96.7%on the digital image was obtained in 100 epochs,which is more accurate than other memristor-based neural *** results show that the memristor device based on CsPbBr3 has immense potential in the neuromorphic computing system.

关键词： Memristor CsPbBr_(3) Resistive switching Artificial synapse Neuromorphic computing

Review on catalytic roles of rare earth elements in ammonia synthesis:Development and perspective

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Journal of Rare Earths 2022年第1期40卷 1-10页

作者： Lingling Li Tianhua Zhang Yanliang Zhou Xiuyun Wang chak-tong au Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China

Ammonia(NH3)is mainly produced via the Haber-Bosch *** was discovered that the performance of a wide variety of catalysts in NH3 synthesis could be considerably enhanced by the addition of rare earth elements(REEs).As a result,catalysts promoted by REEs,especially the Ru-based ones have been extensively *** this review,we summarize the progress of utilizing REEs for ammonia synthesis and outline the prospects of using them in the design and development of highly efficient and stable catalysts for ammonia synthesis.

关键词： Ammonia synthesis catalyst Rare earth elements Thermal catalytic process Catalytic role Sustainable routes

Preparation and phase change performance of Na_2HPO_4·12H_2O@poly(lactic acid) capsules for thermal energy storage

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Chinese Journal of Chemical Engineering 2019年第3期27卷 695-700页

作者： Na Fan Lang Chen Guoyong Xie Donghong Yin chak-Tong au Shuangfeng Yin State Key Laboratory of Chemo/Biosensing and Chemometrics Provincial Hunan Key Laboratory for Cost-effective Utilization of Fossil Fuel Aimed at Reducing Carbon-dioxide Emissions College of Chemistry and Chemical Engineering Hunan University Hunan Tobacco Industry Co. Ltd. College of Chemistry and Chemical Engineering Hunan Institute of Engineering

Micro-encapsulated phase-change materials(micro PCMs) with Na_2 HPO_4·12 H_2 O encapsulated in poly(lactic acid)(PLA) shell were prepared by a solvent evaporation–precipitation method that involves the use of a coaxial needle. The effects of PLA concentration, stirring speed, injection rate of core and shell solutions, and polyvinyl alcohol(PVA) concentration on phase change properties were investigated. The thermal properties of microP CMs were characterized by differential scanning calorimetry(DSC). The capsules prepared under the optimal conditions are about 2 mm in diameter and show a latent heat of up to 122.2 J·g^(-1).

关键词： Micro-encapsulated Phase-change materials Na2HPO4·12H2O Coaxial needle Poly(lactic acid) Thermal energy storage capsule