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High-resolution remote thermometry based on Bi-doped 0D zinc halide hybrids

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Science China Chemistry 2024年

作者： cui-mi shi Shu-Hua Xue Jin-Yun Wang Liang-Jin Xu Zhong-Ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China University of Chinese Academy of Sciences

Developing highly sensitive optical thermometers is of great significance due to their capability to enable remote and non-contact temperature measurements, rendering them highly applicable in diverse and harsh environments. Herein we report a temperature-dependent phosphor of 0D metal halide hybrid by incorporating Bi3+into the（MePPh3）2ZnCl4matrix. Through Bi3+doping,the initially non-luminescent（MePPh3）2ZnCl4matrix exhibits a deep-blue emission centered at 453 nm, with a photoluminescence quantum yield（PLQY） of 5.71% and a Stokes shift of 75 nm at room temperature. Experimental characterization demonstrates that exciton-like luminescence of Bi3+is mainly responsible for the blue emission. Single crystals of Bi3+-doped（MePPh3）2ZnCl4show an unusual correlation between photoluminescence（PL） lifetime and temperature. Particularly, the dependence of luminescence lifetime on temperature is most remarkable in the temperature range of 80 to 100 K with an exceptional sensitivity up to 0.09 K-1, representing one of the best levels for thermometry based on PL decay lifetime. Our work not only provides a viable strategy for designing a novel, environmentally friendly, and stable blue emitter, but also paves the way for precise thermometric application at low temperature.

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Experimental study on the size effect on the equation of state of concretes under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 160-167页

作者： Mei Li Jian cui Yanchao shi Baijian Tang Xin Chen Key Laboratory of Coast Civil Structural Safety of the ministry of Education Tianjin UniversityTianjin 300072China School of Civil Engineering Suzhou University of Science and Technology1701 Binhe RoadSuzhou 215011JiangsuChina School of Civil Engineering Tianjin UniversityTianjin 300072China

Adopting the classical theory of hydrocodes,the constitutive relations of concretes are separated into an equation of state(EoS)which describes the volumetric behavior of concrete material and a strength model which depicts the shear properties of *** experiments on the EoS of concrete is always challenging due to the technical difficulties and equipment limitations,especially for the specimen size effect on the *** some researchers investigate the shock properties of concretes by fly-plate impact tests,the specimens used in their tests are usually in one *** this paper,the fly-plate impact tests on concrete specimens with different sizes are performed to investigate the size effect on the shock properties of concrete *** mechanical background of the size effect on the shock properties are revealed,which is related to the lateral rarefaction effect and the deviatoric stress produced in the *** to the tests results,the modified EoS considering the size effect on the shock properties of concrete are proposed,which the bulk modulus of concrete is unpredicted by up to 20% if size effects are not accounted for.

关键词： Concrete Equation of state Size effect Shock wave Fly-plate impact test

Reduction behavior of iron ore powder by high-volatile coal in thermogravimetric-gas chromatographic and kinetic analysis

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Journal of Iron and Steel Research(International) 2024年第1期31卷 92-107页

作者： Rui-meng shi Qi-yuan mi Bin Li Xiao shi Chong Zou Jing Guo Han-jie Guo School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina China International Engineering Consulting Corporation Beijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The reduction behavior of iron ore powder by high-volatile coal was investigated,and its kinetic mechanism was *** effect of volatiles in coal on the reduction reaction of iron ore was compared by utilizing a Xinjiang lignite with a high volatile content and its pyrolysis carbon produced by high-temperature pyrolysis to remove volatiles,serving as a *** mass loss and gas composition of the samples during the reduction process were detected using thermo-gravimetric analysis and gas chromatography,and the morphological changes of iron ore powder were observed through scanning electron *** kinetic parameters of the iron oxide reduction reaction were calculated by the Flynn-Ozawa-Wall method,and the kinetic mechanism of volatile participation in the iron oxide reduction reaction was determined through the Coats-Redfern *** results indicate that the coupling effect between the high-volatile coal pyrolysis and reduction reactions occurs during the second stage of the entire coupling process,which corresponds to the late stage of coal pyrolysis with a substantial release of H_(2)and *** volatiles in coal actively participated in the reduction reaction,reducing the initiation temperature of the reaction by around 200℃.The reduction of iron oxides by high-volatile coal was jointly promoted by the"hydrogen cycle"and"carbon cycle",resulting in a higher reduction extent and metallization rate at the end of the *** high-volatile coal was used as the reductant,the average activation energy for the entire process was 76.5 kJ/mol,a significant decrease compared to the employment of pyrolysis carbon without volatiles as the reductant(1167 kJ/mol).

关键词： Direct reduction High-volatile coal Volatile Kinetics Reduction mechanism

Geometric quality evaluation of three-dimensional printable concrete using computational fluid dynamics

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 963-976页

作者： Weijiu cui Haijun SUN Jiangang ZHOU Sheng WANG Xinyu shi Yaxin TAO Department of Civil Engineering Qingdao University of TechnologyQingdao 266000China Innovation Institute for Sustainable Maritime Architecture Research and Technology Qingdao University of TechnologyQingdao 266000China Intelligent Construction Lab Qingdao University of TechnologyQingdao 266000China Shandong Zhaojin Industrial Development Co. Ltd.Yantai 264000China Architectural Engineering Institute Weifang Engineering Vocational CollegeWeifang 261000China Qingjian Group Co. Ltd.Qingdao 266000China College of Architecture and Urban Planning Qingdao University of TechnologyQingdao 266000China Department of Structural Engineering and Building Materials Ghent UniversityGhent 9000Belgium Institute of Building Materials ETH ZurichZurich 8064Switzerland

The importance of geometrical control of three dimensional(3D)printable concrete without the support of formwork is widely *** this study,a numerical model based on computational fluid dynamics was developed to evaluate the geometrical quality of a 3D printed *** numerical results were compared,using image analysis,with physical cross-sectional sawn *** influence of printing parameters(printing speed,nozzle height,and nozzle diameter)and the rheological behavior of printed materials(yield stress),on the geometrical quality of one printed layer was *** addition,the yield zone of the printed layer was analyzed,giving insights on the critical factors for geometrical control in 3D concrete *** indicated that the developed model can precisely describe the extrusion process,as well as the cross-sectional quality.

关键词： digital fabrication 3D concrete printing geometric quality computational fluid dynamics printing parameters yield stress

Progress and perspective on rechargeable magnesium-ion batteries

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Science China Chemistry 2024年第1期67卷 214-246页

作者： Guixin Wang Zhechen Wang Hucheng shi Aobing Du mingliang Sun Guanglei cui School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101China

Current electrochemical energy storage technology has evolved a variety of rechargeable battery ***,the resource shortage of raw materials in commercially available lithium-ion batteries has attracted widespread *** requirements to meet resourcefulness,sustainability,safety,and high energy density have motivated the development of rechargeable magnesium-ion batteries(RMBs).Although RMBs have made significant progress so far,there are still many obstacles to practical *** systematically summarize the significant progress and the latest research on RMBs,including Mg^(2+)-conducting electrolytes,Mg^(2+)-storage cathodes,and Mg-based *** this review,we mainly introduce the properties and features of various Mg^(2+)-conductive electrolytes,the mainstream cathode materials,and their respective Mg^(2+)-storage mechanisms,as well as the Mg metal(or alloy)anodes and the corresponding modification ***,the future directions in various key components for RMBs are highlighted.

关键词： rechargable magenisum-ion batteries electrolytes cathodes anodes

Phosphotungstic acid immobilized on amino-functionalized TS-1 zeolite as a solid acid catalyst for the synthesis of tributyl citrate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 199-210页

作者： Pei Li Bianfang shi Junyao Shen Ran cui Wenze Guo Ling Zhao Zhenhao Xi State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol.γ-Aminopropyltriethoxysilane(APTES)was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups,and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic *** Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the *** amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization,which promoted the dispersity,abundance,as well as the stability of the acid *** tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites,and the protons from the immobilized HPW acted as the moderate or strong Brønsted acid *** optimized TBC yield of 96.2%(mol)with a conversion of-COOH of 98.1%(mol)was achieved at 150℃for 6 h over the HPW immobilized on amino-functionalized *** catalyst exhibited good stability after four consecutive reaction runs,where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW.

关键词： Amino-functionalization Phosphotungstic acid TS-1 zeolite Esterification Tributyl citrate

Influence of Flap Parameters on the Aerodynamic Performance of a Wind-Turbine Airfoil

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Fluid Dynamics & Materials Processing 2024年第4期20卷 771-786页

作者： Yuanjun Dai Jingan cui Baohua Li Cong Wang Kunju shi Mechanical College Shanghai DianJi UniversityShanghai201306China College of Energy Engineering Xinjiang Institute of TechnologyUrumqi830091China

A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coefficient,and drag *** numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil;however,at small attack angles,its influence is significantly *** the angle of attack exceeds the critical stall angle and the flap height is 1.5%of the chord length,the influence of the flap becomes very *** the flap height increases,the starting point of the separation vortex gradually moves forward and generates a larger wake *** aerodynamic characteristics are obtained for 1.5%(of the chord length)flap height and a 45°flap angle;in this case,the separation vortex is effectively reduced.

关键词： Airfoil flap height flap angle lift-drag ratio aerodynamic characteristics

Nonlinear Flap-Wise Vibration Characteristics ofWind Turbine Blades Based onMulti-Scale AnalysisMethod

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Energy Engineering 2024年第2期121卷 483-498页

作者： Qifa Lang Yuqiao Zheng Tiancai cui Chenglong shi Heyu Zhang School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou730050China

This work presents a novel approach to achieve nonlinear vibration response based on the Hamilton *** chose the 5-MW reference wind turbine which was established by the National Renewable Energy Laboratory(NREL),to research the effects of the nonlinear flap-wise vibration *** turbine wheel is simplified by treating the blade of a wind turbine as an Euler-Bernoulli beam,and the nonlinear flap-wise vibration characteristics of the wind turbine blades are discussed based on the simplification ***,the blade’s large-deflection flap-wise vibration governing equation is established by considering the nonlinear term involving the centrifugal ***,it is truncated by the Galerkin method and analyzed semi-analytically using the multi-scale analysis method,and numerical simulations are carried out to compare the simulation results of finite elements with the numerical simulation results using Campbell diagram analysis of blade *** results indicated that the rotational speed of the impeller has a significant impact on blade *** the wheel speed of 12.1 rpm and excitation amplitude of 1.23 the maximum displacement amplitude of the blade has increased from 0.72 to *** the amplitude-frequency curve,it can be seen that the multi-peak characteristic of blade amplitude frequency is under centrifugal *** phase trajectories in blade nonlinear vibration,exhibiting periodic motion characteristics,are found through phase diagrams and Poincare section diagrams.

关键词： Wind turbine blades nonlinear vibration Galerkin method multi-scales method

Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2024年第10期30卷 1393-1404页

作者： ming-Hui Zeng Qi-Yu shi Liang Xu Yu-Qiang mi Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Gastroenterology Cangzhou People’s HospitalCangzhou 061000Hebei ProvinceChina Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Tianjin Research Institute of Liver Diseases Tianjin 300192China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic *** date,no drugs have been approved for the treatment of NAFLD,making the correction of unhealthy lifestyles the principle method of *** patients with poor adherence to lifestyle correction and attempting to improve their adherence are therefore very *** To develop and validate a scale that can rapidly assess the adherence of patients with NAFLD to lifestyle *** The Exercise and Diet Adherence Scale(EDAS)was designed based on com-pilation using the Delphi method,and its reliability was subsequently *** and laboratory indicators were measured,and patients completed the EDAS questionnaire at baseline and after 6 *** efficacy of the EDAS was evaluated in the initial ***,the efficacy of the EDAS was internally verified in a validation *** The EDAS consisted of 33 items in six dimensions,with a total of 165 *** EDAS score correlated significantly with daily number of exercise and daily reduction in calorie intake(P500 kacl/d),(sensitivity/specificity was 100.0%/75.8%),while patients score below 97 could nearly rule out the possibility of daily exercise(sensitivity/specificity was 89.5%/44.4%).Total EDAS scores≥116,97-115,and<97 points were indicative of good,average,and poor adherence,respectively,to diet and exercise *** The EDAS can reliably assess the adherence of patients with NAFLD to lifestyle interventions and have clinical application in this population.

关键词： Fatty liver Lifestyle intervention Behavioral change Patient adherence Compliance