检索结果-南通市图书馆

Tungsten 2024年第2期6卷 454-464页

作者： Meng-Long Liu xu Han wen-wen He Feng-Yu Jiang Fang Ji Wang-Wang Shen Tao Zhou Jing-Mei xu Ya-Qian Lan School of Chemistry and Life Science Changchun University of TechnologyChangchun 130012China Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012China School of Chemistry South China Normal UniversityGuangzhou 510006China

Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membranes(PEMs).In this study,a series of hybrid membranes were obtained by molecular-level hybridization of Weakley-type POM Na_(7)H_(2)LaW_(10)O_(36)(LaW_(10))clusters into sulfonated poly(aryl ether ketone sulfone)(SPAEKS).All hybrid membranes exhibited greater proton conductivity than the pristine membrane in the 30–80℃temperature range.When the doping amount of LaW 10 reached 7 wt.%,the proton conductivity of M-LaW 10^(-7)achieved 64 mS·cm^(−1)at 80℃.Lanthanide ions'high coordination number property and variable coordination environment can aid to attract more water molecules from the environment.LaW 10 and these bound water can construct denser hydrogen bonds with–SO_(3)H of SPAEKS.These intensive hydrogen bonds will facilitate the constitution of more continuous proton transport channels,and improve the proton conductivity of the hybrid membrane.This work off ers a fresh approach to using POMs containing rare-earth components in PEMs.

关键词： Polyoxometalates Rare-earth elements Sulfonated poly(arylene ether ketone sulfone) Proton exchange membranes

Thermodynamic geometry of the RN-Ad S black hole and non-local observables

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第2期76卷 137-144页

作者： Chao Wang Bin Wu Zhen-Ming xu wen-Li Yang Institute of Physics Shaanxi University of TechnologyHanzhong 723000China School of Physics Northwest UniversityXi'an 710127China Institute of Modern Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

This paper studies the thermodynamic geometry of the Reissner–Nordstr?m-anti-de Sitter(RN-AdS)black hole via detection of the non-local observables in the dual field theory,including the entanglement entropy and equal-time two-point correlation function.With the dimensional analysis,we construct the principle of corresponding states of black hole thermodynamics.As a result,our findings can be applied to black holes with different Ad S backgrounds.In this sense,the probe of the thermodynamic geometry of the RN-Ad S black hole though the non-local observables in dual field theory has been confirmed numerically.

关键词： black hole thermodynamic thermodynamic geometry phase transition non-local observables

Bioinspired zinc-mediated umpolung thiolation of alkyl electrophiles: reaction development, scope and mechanism

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第3期67卷 898-907页

作者： Yuenian xu Yan Zhang Yong Liu wen-Wu Sun Jie Huang Hui He Yingjie Wu wen Liu Shao-Fei Ni xu-Qiong Xiao Xinxin Shao College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province Shantou UniversityShantou 515063China

Zinc-promoted umpolung thiolation of alkyl electrophiles with masked sulfur transfer reagents in the absence of nickel or copper catalysis is described. This protocol proceeds via a SET process of Zn to electrophilic sulfur reagent followed by insertion of Zn into disulfide and nucleophilic thiolation, providing straightforward access to a wide range of alkyl sulfides with broad substrate scope. A neutral TMEDA-ligated four-coordinated zinc thiolate with tetrahedra geometry was synthesized, isolated and fully characterized by NMR, IR and X-ray analysis. More importantly, the chemical reactivity of this active intermediate has been investigated, enabling the construction of C-Se, C-Te, Sb-S and Bi-S bonds to prepare valuable sulfur-containing molecules and beyond.

关键词： umpolung thiolation C(sp^(3))-S bond formation masked sulfur reagents reductive coupling

Flexo-photocatalysis in centrosymmetric semiconductors

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 1173-1181页

作者： Kang Liu tong Wu Luying xu Zhuangzhuang Zhang Zhiyu Liu Longfei Wang Zhong Lin Wang Center on Nanoenergy Research School of Physical Science&TechnologyGuangxi UniversityNanning 530004China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China Georgia Institute of Technology AtlantaGA 30332-0245USA Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea

The separation of photogenerated electron–hole pairs is vitally important for photocatalysis,which can be effectively promoted by polarization field.However,it only manifests in piezoelectric/pyroelectric/ferroelectric materials that have a non-centrosymmetric structure.Here,we demonstrate that the polarization enhanced photocatalysis(with wide spectra from ultraviolet(UV)light to visible light)can be achieved in centrosymmetric semiconductors,such asδ-MnO_(2) and TiO_(2) nanosheets integrated nanoflowers,by using the strain-gradient-induced flexoelectric polarization that is always overlooked in polarization-enhanced catalysis.Under ultrasonic and illumination excitation,the organic pollutants(methylene blue(MB),etc.)can be effectively degraded within 30 min with excellent stability and repeatability.Compared with photocatalysis,the flexo-photocatalytic performance of above centrosymmetric semiconductors is substantially increased by 85%.Moreover,the factors related to flexo-photocatalysis such as material morphology,mechanical stimuli source,and adsorption are explored to deeply understand the mechanism of flexo-photocatalysis.This work opens up a way for high-performance photocatalysis in centrosymmetric semiconductors.

关键词： piezo-photocatalysis photocatalysis flexoelectricity polarization centrosymmetric semiconductor

Effect of Pre-strain on Microstructure and Stamping Performance of High-strength Low-alloy Steel

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 774-780页

作者：刘坡 wen Zhicheng LIU Zheng 许峰 School of Mechanical Engineering Guilin University of Aerospace TechnologyGuilin 541004China School of Automotive Engineer-ing Changshu Institute of TechnologyChangshu 215500China

In this study,pre-strain ranging from 0 to 0.12 was applied through uniaxial tension on high-strength low-alloy(HSLA)specimens with four kinds of grain size.Effect of pre-strain and grain size on me-chanical property was investigated through tensile tests.Microstructures of the pre-strained and tensile tested samples were analyzed,respectively.The 30.8°v-bending and following flattening,as well as Erichson cupping tests,were performed on the pre-strained samples.Results show the elongation ratio of grain and dislocation density increases with pre-strain.Yielding platform is removed when pre-strain is larger than 0.06 while yielding plateau period decreases with pre-strain less than 0.06 due to reduction of pinning effect.The 30.8°v-bending and the following flattening tests are successfully accomplished on all the pre-strained samples with different grain size.Decrease in grain size,along with increase in pre-strain,causes increase in strength and decrease in elongation rate as well as cupping value.Pre-strain causes very slight effect on bending ability,much less than that on mechanical property and cupping test value.Reciprocal impact of the pre-strain and grain size on HSLA steel deformability is inconspicuous.

关键词： strain hardening dislocation texture bending erichson cupping test

Direct generation of Zn metal using laser-induced ZnS to eradicate carbon emissions from electrolysis Zn production

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第1期18卷 83-95页

作者： Ying Chen Ning Duan Linhua Jiang Fuyuan xu Guangbin Zhu Yao Wang Yong Liu wen Cheng Yanli xu State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China School of Materials Science and Engineering Anhui University of Science&TechnologyHuainan 232001China

In response to the goal of net-zero emissions proposed by Intergovernmental Panel on Climate Change, Chinese government has pledged that carbon emissions will peak by 2030, and achieve carbon neutrality by 2060. However, the high carbon energy structure of traditional industries has aggravated environmental problems, such as greenhouse effect and air pollution. The goal of carbon neutrality will be difficult to achieve without the development of disruptive theories and technologies. The electrolytic zinc industry requires high-temperature roasting at ~1000 ℃, generating large amounts of greenhouse gases and SO_(2). High concentrations of sulfuric acid (200 g/L) are subsequently used for electrolysis, and each ton of zinc produced generates 50 kg of anode slime with lead content of up to 16%, as well as 0.35 m3 of wastewater containing zinc and lead. To solve these problems, an optical metallurgy method is proposed in this study. The proposed method uses laser-induced photoreduction to decompose ZnS and reduce metal ions to metal. Results indicate that Zn0 and S8 can be detected on the surface of ZnS at a specific wavelength and laser fluence. The generation mechanism of Zn0 is such that laser induces an electronic transition that breaks ionic bond in ZnS, resulting in its decomposition and photoreduction to Zn0 under an inert argon gas atmosphere. This method does not reduce other metals in the mineral since it does not use high-temperature roasting, providing a new way of producing high-purity metal without greenhouse gas emissions and heavy metal pollution caused by traditional zinc electrolysis.

关键词： Laser metallurgy ZnS Photochemical reduction Zinc

Protein C deficiency with venous and arterial thromboembolic events

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第12期12卷 2000-2003页

作者： Nan Zhang Dong-Kun Sun xu Tian Xin-Yu Zheng tong Liu Department of Cardiology Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular DiseaseTianjin Institute of CardiologyThe Second Hospital of Tianjin Medical UniversityTianjin 300211China

Protein C(PC)is a key component of the vitamin K-dependent coagulation pathway.It exerts anticoagulant effects by inactivating factors V and VIII.Acquired or inherited PC deficiency results in a prothrombotic state,with presentations varying from asymptomatic to venous thromboembolism.However,there has been an increasing number of reports linking PC deficiency to arterial thromboembolic events,such as myocardial infarction and ischemic stroke.This editorial focuses on the association between PC deficiency and thromboembolism,which may provide some insights for treatment strategy and scientific research.

关键词： Protein C deficiency Venous thromboembolism Myocardial infarction Editorial Arterial thromboembolism

Design study of charge-stripping scheme of heavy ion beams for HIAF-BRing

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第5期35卷 30-41页

作者： Jun-Jie Zhang Zhi-You xu Jin-Quan Zhang wen-wen Ge Liang-Ting Sun Huan-Yu Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Charge strippers play an essential role in heavy-ion accelerators by stripping the projectile ions to higher charge states to enhance the acceleration efficiency downstream of the stripper.In the high-energy mode of the booster ring(BRing)of the high-intensity heavy-ion accelerator facility,the pre-accelerated ions from the iLinac will be stripped by a carbon foil to higher charge states and then injected into the BRing.The key parameters of the stripper and stripped ions were calculated,and the influence of stripping on the beam quality was discussed.To get high stripping efficiencies,the foil thicknesses and resultant charge state distributions for the typical ions were determined by the code ETACHA.The equilibrium thickness was obtained for the U beam,while the stripper thicknesses for the Xe and Kr beams were determined based on a compromise between the stripped charge states and the stripping efficiency.The energy loss,energy straggling,and emittance growth due to stripping have a non-negligible impact on the transport of the stripped beams and the injection of the ring.Therefore,these parameters were simulated by GEANT4.In addition,the foil’s temperature evolution,which greatly affects the foil lifetime,was simulated by ANSYS.The maximum temperature of the foil bombarded by the U and Xe beams with the nominal parameters will exceed the safe value in terms of the impact of evaporation on the foil’s lifetime.Given the foil temperature constraint,the highest tolerable beam intensity and the injected ion number into the ring were derived for different beam sizes.The results of this paper will present important reference data for the optimization design and commissioning of the beamline and injection to the BRing for the stripped ions.

关键词： High-intensity heavy-ion accelerator facility Charge stripper Energy spread Thermal analysis Emittance growth Injection turns

Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第1期65卷 75-84页

作者： wen Xiao Peng Dong Chan Wang Jingdong xu Tiesen Li Haibo Zhu Tinghai Wang Renwei xu Yuanyuan Yue National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou 362801China Sinochem Quanzhou Energy Technology Co. Ltd.Quanzhou 362000China

Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficiency.Herein,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical 2-cyano-3-phenylacrylate.The synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or seed.Systematic characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX zeolite.Detailed mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized kaolinite.This synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing.

关键词： Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation

Theoretical and experimental design in the study of sulfide-based solid-state battery and interfaces

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第2期35卷 242-251页

作者： Hongjie xu Yujie Su Chenggong Zheng Yuchen Wang Yuping tong Zhongzheng Yang Junhua Hu School of Materials Science and Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Titanium Based Advanced Materials Industrial Research Institute Jiaozuo 454191China

In recent years,due to the increasing demand for portable electronic devices,rechargeable solid-state battery technology has developed rapidly.Lithium-ion batteries are the systems of choice,offering high energy density,flexible and lightweight design,and longer lifespan than comparable battery technologies.Therefore,a better understanding of the relationship between electrochemical mechanism and structural properties from theory and experiment will enable us to accelerate the development of high-performance and security batteries.This review discusses the interplay between theoretical calculation and experiment in the study of lithium ion battery materials.We introduce the application of theoretical calculation method in solid-state batteries through the combination of theory and experiment.We present the concept and assembly technology of solid-state batteries are reviewed.The basic parameters of solid-state electrolytes,especially sulfide-based solid-state electrolytes and their interface mechanisms with high-voltage cathode materials,are analyzed by theoretical methods.We present an overview on the scientific challenges,fundamental mechanisms,and design strategies for solid-state batteries,especially focusing on the issues of stability on solid-state electrolytes and the associated interfaces with both cathode and electrolyte.Owing to the theoretical models,we can not only reveal the unprecedented mechanism from the atomic scale,but also analyze the interface problems in the battery thoroughly,thus effectively designing more promising electrolyte and interface coating materials.It blazed a new trial for engineering an interphase with improved interfacial compatibility for a long-term cyclability.

关键词： Theoretical simulation Sulfide-based electrolytes All solid-state battery Cathode-electrolyte interface Interface compatibility