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Chinese Physics B 2024年第3期33卷 393-400页

作者：江孝伟方彬占春连 college of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018China college of Information Engineering Quzhou College of TechnologyQuzhou 324000China

Quasi-bound state in the continuum(QBIC)resonance is gradually attracting attention and being applied in Goos-Hänchen(GH)shift enhancement due to its high quality(Q)factor and superior optical ***,symmetry-protected QBIC resonance is often achieved by breaking the geometric symmetry,but few cases are achieved by breaking the material *** paper proposes a dielectric compound grating to achieve a high Q factor and high-reflection symmetry-protectede QBIC resonance based on material *** calculations show that the symmetry-protected QBIC resonance achieved by material asymmetry can significantly increase the GH shift up to-980 times the resonance wavelength,and the maximum GH shift is located at the reflection peak with unity *** paper provides a theoretical basis for designing and fabricating high-performance GH shift tunable metasurfaces/dielectric gratings in the future.

关键词： bound state in the continuum Goos-Hänchen shift dielectric compound grating material asymmetry

Asymmetric copolyimide membranes fabricated by nonsolvent-induced phase separation for He/CH_(4) and He/N_(2) separation

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 97-106页

作者： Ying Li Lu Wang Junyan Xie Yong Dai Xuehong Gu Xuerui Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China quzhou Membrane Material Innovation Institute Quzhou 324000China

Membrane gas separation is considered an energy-saving technique to extract He from natural gas due to no phase change and room temperature ***,the membrane performance was strongly limited by the trade-off between permeance and ***,novel 4,4′-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)-2,2′-bis(3-amino-4-hydroxyphenyl)hexafluoropropane(APAF)-5-amino-2-(4-aminobenzene)benzimidazole(BIA)asymmetric membranes with a thickness of 300 nm were successfully prepared by the non-solvent induced phase separation *** membrane performance was modulated by regulating dope solution compositions(e.g.,tetrahydrofuran and polymer concentration).The ideal He/CH_(4) selectivity was 124 and the optimized He permeance reached 87 GPU,beyond the current upper ***/CH_(4) selectivity was 75 and He permeance was 73 GPU for the binary mixture feed containing 0.2 mol%*** membrane showed good resistance to CO_(2) and C_(2)H_(6),which are the typical impurities in natural *** 6FDA-APAF-BIA membranes have good stability(>160 h),which can provide great potential in He extraction from natural gas.

关键词： He separation membrane natural gas copolyimide

Trudinger–Moser Inequalities on a Closed Riemann Surface with a Symmetric Conical Metric

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2263-2284页

作者： Yu FANG Yun Yan YANG college of Teacher Education Quzhou UniversityQuzhou 324003P.R.China Department of Mathematics Renmin University of ChinaBeijing 100872P.R.China

This is a continuation of our previous work(*** ***.,20,1295–1324,2020).Let(Σ,g)be a closed Riemann surface,where the metric g has conical singularities at finite *** G is a group whose elements are isometries acting on(Σ,g).Trudinger–Moser inequalities involving G are established via the method of blow-up analysis,and the corresponding extremals are also *** extends previous results of Chen(***.,1990),Iula–Manicini(Nonlinear Anal.,2017),and the authors(2020).

关键词： Trudinger-Moser inequality blow-up analysis conical singularity

Temperature-dependent solubility of Rebaudioside A in methanol/ethanol and ethyl acetate mixtures:Experimental measurements and thermodynamic modeling

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Chinese Journal of Chemical Engineering 2024年第8期72卷 164-176页

作者： Zhenguang Liu Zexiang Ding Yifeng Cao Baojian Liu Qiwei Yang Zhiguo Zhang Qilong Ren Zongbi Bao Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China Institute of Zhejiang University-quzhou Quzhou 324000China

The equilibrium solubility of Rebaudioside A(Reb A)FormⅡin binary mixtures of methanol/ethanol and ethyl acetate was quantitatively determined within the temperature range of 283.15—328.15 K at ambient *** experimental findings indicate a positive correlation between the solubility of Reb A(FormⅡ)and both the temperature and the methanol/ethanol content in the solvent *** describe the solubility data,six distinct models were employed:the modified Apelblat equation,theλh model,the combined nearly ideal binary solvent/Redlich—Kister(CNIBS/R—K)model,the van't HoffJouyban-Acree(VJA)model,the Apelblat-Jouyban-Acree(AJA)model,and the non-random two-liquid(NRTL)*** combined nearly ideal binary solvent/Redlich—Kister model exhibited the most precise fit for solubility in methanol+ethyl acetate mixtures,reflected by an average relative deviation(ARD)of 0.0011 and a root mean square deviation(RMSD)of 12×10^(-7).Conversely,for ethanol+ethyl acetate mixtures,the modified Apelblat equation provided a superior correlation(ARD=0.0014,RMSD=4×10^(-7)).Furthermore,thermodynamic parameters associated with the dissolution of Reb A(FormⅡ),including enthalpy,entropy,and the Gibbs energy change,were inferred from the *** findings underscore that the dissolution process is predominantly endothermic across the solvent systems ***,the entropy changes appear to have a significant influence on the Gibbs free energy associated with the dissolution of Reb A(FormⅡ),suggesting that entropic factors may play a pivotal role in the studied systems.

关键词： Rebaudioside A Solubility Thermodynamic modeling Dissolution Binary solvent

Microstructure Recrystallization and Mechanical Properties of a Cold-Rolled TiNbZrTaHf Refractory High-Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 633-647页

作者： Chuan Rong Jieren Yang Xiaoliang Zhao Ke Huang Ying Liu Xiaohong Wang Dongdong Zhu Ruirun Chen college of Materials Science and Engineering Sichuan UniversityChengdu610065China Key Laboratory of Air-Driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou324000China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

The equiatomic TiNbZrTaHf alloy was successfully rolled at room temperature with the reduction of ~ 85%. The microstructure and tensile properties were investigated after cold working and annealing. It was determined that the recrystallization temperature of the TiNbZrTaHf alloy between 850 and 900 ℃. Complete recrystallization and normal grain growth occurred, the high stability of single phase was maintained after annealing at 1000, 1200, and 1400 ℃. But the precipitated phase appeared after long term annealing, as seen after 500 h at 1000 ℃. After cold working, the tensile strength and the elongation of TiNbZrTaHf were 1137 MPa and 25.1%, respectively. The annealed alloy has a high tensile strength (σ_(b )= 863 MPa) and ductility (ε_(e )= 28.5%). Moreover, the oxidation of TiNbZrTaHf alloy at elevated temperatures has a significant impact on its mechanical properties. The poor oxidation resistance of TiNbZrTaHf can accelerate tensile failure by inducing fractures at grain boundaries.

关键词： Refractory high entropy alloy Cold rolling Recrystallization Oxidation resistance Mechanical properties

Recent Advance in Electrocatalytic Water Splitting for Hydrogen Production by Layered Double Hydroxides

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Chemical Research in Chinese Universities 2024年第4期40卷 577-589页

作者： XIA Tian REN Qinghui YANG Jiangrong LI Zhenhua SHAO Mingfei DUAN Xue State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing100029P.R.China quzhou Institute for Innovation in Resource Chemical Engineering Quzhou324000P.R.China

Collecting green hydrogen(H2)from water splitting driven by renewable energy is a new competition to implement the construction of H2 energy industry and promote new economic growth for global *** common strategy to enhance the efficiency of H2 production is to reduce the potential of electrolytic cell that is the mainstream way to prepare efficient *** double hydroxides(LDHs)are one of the most active electrocatalysts with adjustable active sites in contemporary *** this review,we discuss the recent advanced progress of LDHs for hydrogen evolution reaction(HER)on cathode and oxygen evolution reaction(OER)or organic oxidation on anode and emphasize the influence of LDHs structure regulation in water electrolysis process(HER/OER)as well as the current development status of organic oxidation catalyzed by active oxygen species on ***,we propose the current challenges of LDHs in electrocatalysis and prospect their developing tendency and further application.

关键词： Layered double hydroxide Hydrogen production Hydrogen evolution reaction(HER) Oxygen evolution reaction(OER) Electrocatalytic organic oxidation

Transient Experiments on a Prototype Pump with an Atypical Open Impeller for Different Discharge Valve Openings

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Fluid Dynamics & Materials Processing 2024年第10期20卷 2251-2264页

作者： Xiao Sun Huifan Huang Yuliang Zhang Lianghuai Tong Xiaowei Xu Xiaoqi Jia Litao Ou School of Mechanical Engineering Hunan University of TechnologyZhuzhou412007China college of Mechanical Engineering Quzhou UniversityQuzhou324000China quzhou Academy of Metrology and Quality Inspection Quzhou324024China The Zhejiang Provincial Key Lab of Fluid Transmission Technology Zhejiang Sci-Tech UniversityHangzhou310018China Zhuzhou Nanfang Valve Co. Ltd.Zhuzhou412000China

In order to obtain the transient characteristics of a low-speed centrifugal pump during the start-up and shutdown stages,dedicated experimental tests were conducted with eight different valve opening *** Pearson correlation coefficient was used to reveal the linear correlation between *** to the results,the stable rotational speed decreases with increasing valve opening(rotational speed decreases from approximately 1472 to 1453 r/min),while the stable shaft power exhibits an increasing trend(shaft power increases from approximately 0.242 to 0.390 kW).The stable time and zeroing time of each parameter during start-up and shutdown processes vary,with the flow zeroing time significantly increasing with the relative flow,reaching up to 10.468 s,while the shaft power zeroing time is roughly between 1.219 and 1.375 *** results demonstrate that with increasing valve opening,the stable and zeroing time of flow significantly increase(|r|greater than 0.95),while the stable and zeroing time of rotational speed,power,and head display a smaller sensitivity on the valve opening(|r|less than 0.6).

关键词： Centrifugal pump startup shutdown external characteristics zeroing time

Direct Conversion of Methane to Propylene

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Research 2024年第2期2023卷 463-472页

作者： Yunpeng Hou Yuxiang Lan Chao Qian Shaodong Zhou college of Chemical and Biological Engineering Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyZhejiang University310027 HangzhouP.R.China Zhejiang Provincial Innovation Center of Advanced Chemicals Technology Institute of Zhejiang University-Quzhou324000 QuzhouP.R.China

Nonoxidative coupling of methane exhibits promising prospect in that it affords value-added hydrocarbons and hydrogen with high atom ***,challenge remains in direct,selective conversion of methane to more valuable hydrocarbons like *** current work presents a catalyst with well-dispersed Ta atoms anchored by graphitic C_(3)N_(4)-supported *** a catalyst is able to convert methane selectively to ethylene and propylene at a relatively low temperature(350℃).The conception of the active center and construction of the catalyst have been described,and the origins of the catalytic performance are discussed.

关键词： methane catalyst hydrocarbons

Complex-frequency waves:beat loss and win sensitivity

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Light(Science & Applications) 2024年第2期13卷 181-183页

作者： Qingqing Cheng Tao L School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Respiratory Diseases and Critical Medicine Quzhou Hospital Affiliated to Wenzhou Medical UniversityQuzhou324000China National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesNanjing UniversityNanjing210093China

Recent experiments have demonstrated that synthesized complex-frequency waves can impart a virtual gain to molecule sensing systems,which can effectively restore information lost due to intrinsic molecular *** enhancement notably amplifies the signal of trace molecular vibrational fingerprints,thereby substantially improving the upper limit of sensitivity.

关键词： thereby Complex limit

Enhancing the Goos–H?nchen shift based on quasi-bound states in the continuum through material asymmetric dielectric compound gratings

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Chinese Physics B 2024年第3期 451-458页

作者：江孝伟方彬占春连 college of Optical and Electronic Technology China Jiliang University college of Information Engineering Quzhou College of Technology

Quasi-bound state in the continuum(QBIC) resonance is gradually attracting attention and being applied in Goos–H?nchen(GH) shift enhancement due to its high quality(Q) factor and superior optical confinement. Currently, symmetryprotected QBIC resonance is often achieved by breaking the geometric symmetry, but few cases are achieved by breaking the material symmetry. This paper proposes a dielectric compound grating to achieve a high Q factor and high-reflection symmetry-protectede QBIC resonance based on material asymmetry. Theoretical calculations show that the symmetryprotected QBIC resonance achieved by material asymmetry can significantly increase the GH shift up to-980 times the resonance wavelength, and the maximum GH shift is located at the reflection peak with unity reflectance. This paper provides a theoretical basis for designing and fabricating high-performance GH shift tunable metasurfaces/dielectric gratings in the future.

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