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g-C_(3)N_(4)nanosheets coupled with CoSe_(2)as co-catalyst for efficient photooxidation of xylose to xylonic acid

Green Energy & Environment 2025年第1期10卷 231-238页

作者： Qi Hao Yijun Liu ren zou Ge Shi Shilian Yang Linxin Zhonga Wu Yang Xiao Chi Yunpeng Liu Shimelis Admassie Xinwen Peng State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou510641GuangdongChina Hainan Key Laboratory of Storage&Processing of Fruits and Vegetables Agricultural Products Processing Research InstituteChinese Academy of Tropical Agricultural SciencesZhanjiangGuangdong524001China Department of Chemistry and Centre for Advanced 2D Materials(CA2DM)National University of Singapore 3 Science Drive 3 Singapore117543Singapore School of Materials Science and Hydrogen Energy Foshan UniversityFoshan528231GuangdongChina Department of Chemistry Addis Ababa UniversityPO BOX 1176Addis AbabaEthiopia

Photocatalysis has emerged as an effective approach to sustainably convert biomass into value-added ***_(2)is a promising nonprecious,efficient cocatalyst for photooxidation,which can facilitate the separation of photogenerated electron–holes,increase the reaction rates,and enhance photocatalytic *** this work,we synthesized a stable and efficient photocatalysis system of CoSe_(2)/g-C_(3)N_(4)through attaching CoSe_(2)on g-C_(3)N_(4)sheets,with a yield of 50.12%for the selective photooxidation of xylose to xylonic *** light illumination,the photogenerated electrons were prone to migrating from g-C_(3)N_(4)to CoSe_(2)due to the higher work function of CoSe_(2),resulting in the accelerated separation of photogenerated electron–holes and the promoted ***,this study reveals the unique function of CoSe_(2),which can significantly promote oxygen adsorption,work as an electron sink and accelerate the generation of$O2-,thereby improving the selectivity toward xylonic acid over other *** work provides useful insights into the design of selective photocatalysts by engineering g-C_(3)N_(4)for biomass high-value utilization.

关键词： Biomass photooxidation Hemicelluloses Xylose g-C_(3)N_(4) Xylonic acid

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THREE-DIMENSIONAL FLOW AROUND TWO TANDEM CIRCULAR CYLINDERS WITH VARIOUS SPACING AT Re=220

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Journal of Hydrodynamics 2006年第1期18卷 48-54页

作者： DENG Jian ren An-lu zou Jian-feng Department of Mechanics Zhejiang University Hangzhou 310027 China

The flow around two tandem circular cylinders was studied by a three-dimensional numerical simulation of the Navier-Stokes equations at Re=220 . The improved virtual boundary method was applied to model the no-slip boundary condition of the cylinders. The results show that as the spac ing ratio L/D≥4 , the three dimensionality occurs in the wake. When L/D≤3.5 the wake keeps a two-dimensional state at the Reynolds number Re=220 . The critical spacing for the appearance of three-dimensional instability obtained is at the range 3.5〈 L/D 〈 4, similar to the critical spacing found in two-dimensional case. Two sources of instability from upstream and downstream cylinder generate a complicat ed vortex structures in the wake, investigated by streamlines topology analysis in the streamwise plane. Many other interesting problems were also addressed in this paper.

关键词： three-dimensional Navier-Stokes equations,virtual boundary method flow around two tandem circular cylinders three-dimensional vortex structure

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Startup scheme optimization and flow instability of natural circulation lead-cooled fast reactor SNCLFR-100

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Nuclear Science and Techniques 2021年第11期32卷 191-200页

作者： Wen-Shun Duan Ze-ren zou Xiao Luo Hong-Li Chen School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China

Owing to the inherent instability of the natural circulation system,flow instability can easily occur during the operation of a natural circulation lead-cooled fast reactor,especially during the startup phase.A comprehensive startup scheme for SNCLFR-100,including primary and secondary circuits,is proposed in this *** references existing more mature startup schemes in various reactor *** additionally considers the restriction conditions on the power increase in other schemes and the characteristics of lead-based *** this basis,the multi-scale coupling code ATHLET-OpenFOAM was used to study the flow instability in the startup phase under different power-step amplitudes and power duration *** results showed that obvious flow instability phenomena were found in the different startup schemes,such as the short-term backflow phenomenon of the core at the initial time of the ***,an obvious increase in the flow rate and temperature to the peak value at the later stage of a continuous power rise was observed,as well as continuous oscillations before reaching a steady *** was determined that the scheme with smaller power-step amplitude and a longer power duration time requires more time to start the ***,it will be more conducive to the safe and stable startup of the reactor.

关键词： Natural circulation Lead-cooled fast reactor Startup scheme Flow instability Multi-scale coupling

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Laboratory study and analysis of the instability of alongshore currents

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Acta Oceanologica Sinica 2009年第4期28卷 96-106页

作者： ren Chunping zou Zhili State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

A laboratory experiment on the instability of alongshore currents was conducted on a plane beach with slope 1：40. Low-frequency fluctuations of alongshore currents with the period of approximately 100 s were observed. The dominant frequency and amplitudes of the oscillations of alongshore currents were determined using the maximum entropy method and the regression method of trigonometric function. The variations across the beach cross-section of the oscillation amplitudes of the alongshore current were given. The linear shear instability theory was used to analyze the mechanism of the oscillation, and the calculated results agreed with measurements. This confirms that the observed fluctuation of alongshore currents is due to the shear instability of alongshore currents.

关键词： alongshore currents shear instability water waves coast

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Cellulose nanofiber-derived carbon aerogel for advanced room-temperature sodium–sulfur batteries

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Carbon Energy 2023年第1期5卷 1-15页

作者： Wu Yang Wang Yang ren zou Yongfa Huang Haihong Lai Zehong Chen Xinwen Peng State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhouChina

Room-temperature sodium–sulfur(RT/Na–S)batteries are regarded as promising large-scale stationary energy storage systems owing to their high energy density and low cost as well as the earth-abundant reserves of sodium and ***,the diffusion of polysulfides and sluggish kinetics of conversion reactions are still major challenges for their ***,we developed a powerful and functional separator to inhibit the shuttle effect by coating a lightweight three-dimensional cellulose nanofiber-derived carbon aerogel on a glass fiber separator(denoted NSCA@GF).The hierarchical porous structures,favorable electronic conductivity,and three-dimensional interconnected network of N,S-codoped carbon aerogel endow a multifunctional separator with strong polysulfide anchoring capability and fast reaction kinetics of polysulfide conversion,which can act as the barrier layer and an expanded current collector to increase sulfur ***,the hetero-doped N/S sites are believed to strengthen polysulfide anchoring capability via chemisorption and accelerate the redox kinetics of polysulfide conversion,which is confirmed from experimental and theoretical *** a result,the assembled Na–S coin cells with the NSCA@GF separator showed a high reversible capacity(788.8 mAh g^(−1) at 0.1 C after 100 cycles)and superior cycling stability(only 0.059%capacity decay per cycle over 1000 cycles at 1 C),thereby demonstrating the significant potential for application in high-performance RT/Na–S batteries.

关键词： carbon aerogel cellulose nanofiber N,S codoping redox kinetics sodium–sulfur batteries

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Development and application of a multi-physics and multi-scale coupling program for lead-cooled fast reactor

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Nuclear Science and Techniques 2022年第2期33卷 40-52页

作者： Xiao Luo Chi Wang Ze-ren zou Lian-Kai Cao Shuai Wang Zhao Chen Hong-Li Chen School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China China Nuclear Power Technology Research Institute Co.Ltd Shenzhen 518000China

In this study,a multi-physics and multi-scale coupling program,Fluent/KMC-sub/NDK,was developed based on the user-defined functions(UDF)of Fluent,in which the KMC-sub-code is a sub-channel thermal-hydraulic code and the NDK code is a neutron diffusion *** coupling program framework adopts the"master-slave"mode,in which Fluent is the master program while NDK and KMC-sub are coupled internally and compiled into the dynamic link library(DLL)as slave *** domain decomposition method was adopted,in which the reactor core was simulated by NDK and KMC-sub,while the rest of the primary loop was simulated using Fluent.A simulation of the reactor shutdown process of M2LFR-1000 was carried out using the coupling program,and the code-to-code verification was performed with ATHLET,demonstrating a good agreement,with absolute deviation was smaller than 0.2%.The results show an obvious thermal stratification phenomenon during the shutdown process,which occurs 10 s after shutdown,and the change in thermal stratification phenomena is also captured by the coupling *** the same time,the change in the neutron flux density distribution of the reactor was also obtained.

关键词： Multi-physics and multi-scale coupling method User-defined functions Dynamic link library Thermal stratification Lead-cooled fast reactor

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NUMERICAL STUDY OF FLOW PAST AN AXISYMMETRIC BODY WITH A RING WING AT VARIOUS ATTACK ANGLES

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Journal of Hydrodynamics 2003年第5期15卷 49-53页

作者： ren An lu, zou Jian feng, Dai Zhi qian Department of Mechanics, Zhejiang University, 310027, China, Dept. of Mech. Zhejiang Univ. Zhejiang 310027 China

The laminar and turbulent flows past an axi-symmetric body with a ring wingwere investigated numerically at various attack angles (0°-20°) for the Reynolds numbers rangingfrom 10~3 to 10~7. The DDM (Domain Decomposition Method) with the Schwarz iterative method based onfinite difference approximation was applied to simulate this problem. The primitive variableformulation was used for the solution of the incompressible Navier-Stoke equations. The velocityfield was calculated from the unsteady momentum equation by marching in time. The continuityequation was replaced by a Poisson-type equation for the pressure with the Neumann boundaryconditions. The Baldwin-Lomax model was adopted to simulate turbulence effect. The leap frogimplicit iterative method was used for the time difference approximations. The computed pressure atthe front stagnation point is found to have a small deviation, less than 10%, from the theoreticalvalue. The outlet flux has a loss about 5%. The lift coefficients increase linearly with the attackangle, but for attack angles greater than 15° the lift coefficients show mild decrease. Thefriction drag coefficients are insensitive to the attack angles, but the pressure drag coefficientsincrease markedly with the attack angles. In addition, complex flow patterns are revealed within thevicinity of the ring wing.

关键词： an axisymmetric body domain decomposition method (DDM) baldwin-lomax model non-staggered grid

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Experimental study of retinoic acid on improving iodide uptake in MCF-7 breast cancer cells

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Nuclear Science and Techniques 2005年第4期16卷 221-224页

作者： FU Hong-Liang WU Jing-Chuan DU Xue-Liang LI Jia-Ning WU Zhen zou ren-Jian Department of Nuclear Medicine Xinhua Hospital Shanghai Second Medical University Shanghai 200092

The study aims to investigate the effect of retinoic acid on the iodide uptake of MCF-7 cells and its mechanism. The iodide uptake and expression of hNIS(human sodium/iodide symporter)mRNA in the breast cancer MCF-7 cells were compared individually before and after the intervention of all-trans retinoic acid (ATRA) with the iodide uptake assay and RT-PCR. The following results are obtained: (1) when treated with all-trans retinoic acid in the concentration of 1.0 μmol/L, the capacity of iodide uptake of MCF-7 cells reached about 1.5 times of the basal state; (2) 12 h after the intervention of 1.0 μmol/L ATRA,the hNISmRNA expression of the MCF-7 cells reached maximum. The study shows that all-trans retinoic acid has the effect to improve the iodide uptake of the MCF-7 cells and this effect may result from its up-regulation of the hNISmRNA expression.

关键词： MCF-7 碘化物乳腺癌放射性疗法

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