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Switchable Multicomponent Cyclization Reactions to Access Fluoroalkylated Dihydropyrimidines and Pyrimidines under Solvent-Free Conditions

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Chinese Journal of Chemistry 2024年第12期42卷 1394-1398页

作者： Wanqing zuo Zhizhen Zhu yu Cheng Lingling zuo Xiao Geng Zhifang Li Lei Wang College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistryof EducationHangzhouNormal UniversityHangzhouZhejiang311121China Advanced Research Institute and School of Pharmaceutical Sciences Taizhou UniversityJiaojiangZhejiang 318000China state Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Comprehensive Summary The development of switchable solvent-free multicomponent reactions to build high-value-added products is an important demand for organic ***,we detailed the successful implementation of a switchable strategy for the construction of diverse 4-fluoroalkyl-1,4-dihydropyrimidines and 4-fluoroalkyl-pyrimidines via a solvent/additive-free[3+2+1]annulation,starting from readily available enamines,trifluoroacetaldehyde hydrate or 1-ethoxy-2,2-difluoroethanol and amidines *** reaction conforms to the concept of green synthesis,and provides a new avenue to access valuable fluorinated heterocycles.

关键词： Fluorine chemistry Multicomponent reactions Environmental chemistry Heterocycles Enaminones Amidines

Flow field effect of delayed neutron precursors in liquid-fueled molten salt reactors

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Nuclear Science and Techniques 2022年第8期33卷 16-32页

作者： Xian-Di zuo Mao-Song Cheng yu-Qing Dai Kai-Cheng yu Zhi-Min Dai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

In molten salt reactors(MSRs),the liquid fuel salt circulates through the primary loop and a part of the delayed neutron precursors(DNPs)decays outside the reactor *** model and analyze the flow field effect of DNPs in channel-type liquid-fueled MSRs,a three-dimensional space-time dynamics code,named ThorCORE3D,that couples neutronics,core thermalhydraulics,and a molten salt loop system was developed and validated with the Molten Salt Reactor Experiment(MSRE)*** effects of external loop recirculation time,fuel flow rate,and core flow field distribution on the delayed neutron fraction loss of MSRE at steadystate were modeled and simulated using the ThorCORE3D ***,the flow field effect of the DNPs on the system responses of the MSRE in the reactivity insertion transient under different initial conditions was analyzed systematically for the channel-type liquid-fueled *** results indicate that the flow field condition has a significant effect on the steady-state delayed neutron fractions and will further affect the transient power and temperature responses of the reactor *** analysis results for the effect of the DNP flow field can provide important references for the design optimization and safety analysis of liquid-fueled MSRs.

关键词： Molten salt reactor Delayed neutron precursor Nodal expansion method Coupled neutronics and thermal-hydraulics

Reduction kinetics of iron oxide pellets with H_2 and CO mixtures

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International Journal of Minerals,Metallurgy and Materials 2015年第7期22卷 688-696页

作者： Hai-bin zuo Cong Wang Jie-ji Dong Ke-xin Jiao Run-sheng Xu State Key Laboratory of Advanced Metallurgy University of Science and Technology of Beijing School of Metallurgical and Ecological Engineering University of Science and Technology of Beijing

Reduction of hematite pellets using H2-CO mixtures with a wide range of H2/CO by molar （1：0, 3：1, 1：1, 1：3, and 0：1） at different reducing temperatures （1073, 1173, and 1273 K） was conducted in a program reducing furnace. Based on an unreacted core model, the effective diffusion coefficient and reaction rate constant in several cases were determined, and then the rate-control step and transition were analyzed. In the results, the effective diffusion coefficient and reaction rate constant increase with the rise in temperature or hydrogen content. Reduction of iron oxide pellets using an H2-CO mixture is a compound control system; the reaction rate is dominated by chemical reaction at the very beginning, competition during the reduction process subsequently, and internal gas diffusion at the end. At low hydrogen content, increasing temperature takes the transition point of the rate-control step to a high reduction degree, but at high hydrogen content, the effect of temperature on the transition point weakens.

关键词： iron oxide pellets reduction kinetics kinetics models hydrogen carbon monoxide

Triarylborane π-electron systems with intramolecular charge-transfer transitions

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Chinese Chemical Letters 2016年第8期27卷 1131-1138,1464页

作者： zuo-Bang Sun sheng-Yong Li Zhi-Qiang Liu Cui-Hua Zhao School of Chemistry and Chemical Engineering Key Laboratory of Special Functional Aggregated Materials Ministry of EducationShandong University State Key Laboratory of Crystal Materials Shandong University

The incorporation of B element into π-conjugated system is an efficient strategy to tune the steric and electronic structure and thus optoelectronic properties of π-electron *** vacant p orbital on the tricoordinate B center makes it exhibit several electronic and steric features,such as electron-accepting ability through p-π~＊ conjugation,the high Lewis acidity to coordinate with Lewis bases,as well as the steric bulk arising from the aryl substituent on the B center to get enough kinetic *** a result,the boryl group is a very unique electron *** an electron-donating amino group is present,the triarylboranes would display intense intramolecular charge transfer transitions,which lead to interesting optoelectronic properties and great *** short review summarizes the recent progress in π-electron systems,which contain both B and N elements and thus display intramolecular charge-transfer *** triarylboranes are introduced based on their structural features,including the linear π-system with boryl and amino groups at the terminal positions,the lateral borylsubstituted π-system with amino groups at the terminal positions,the biphenyl π-system with an amino and a boryl groups at o,o＇-positions,nonconjugated U- and V-shaped π-system,macrocylcic π-system with B and N embedded in the ring,B,N-bridged ladder-type π-system,as well as the polycyclicπ-system with B embedded in the center.

关键词： Triarylborane Electron-acceptor Electron-donor Charge-transfer

Talagrand Inequality on Free Path Space and Application to Stochastic Reaction Diffusion Equations

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Acta Mathematicae Applicatae Sinica 2020年第2期36卷 253-261页

作者： Feng-yu WANG Tu-sheng ZHANG Center for Applied Mathematics Tianjin UniversityTianjin 300072China Department of Mathematics Swansea UniversityBay CampusSAI 8ENUK School of Mathematics University of ManchesterOxford RoadManchester M139PLUK School of Mathematics University of Science and Technology of ChinaHefei 230026China

By using a split argument due to[1],the transportation cost inequality is established on the free path space of Markov *** general result is applied to stochastic reaction diffusion equations with random initial values.

关键词： Stochastic reaction diffusion equations Talagrand transportation cost inequality free path space.

Visible-Light-Induced Domino Cyclization to Access Pyrido[2,3-d]pyrimidine-2,4-diones via a Radical-Polar Crossover Reaction

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Chinese Journal of Chemistry 2024年第19期42卷 2346-2350页

作者： Wanqing zuo yu Cheng Zhizhen Zhu Lingling zuo Xiao Geng Zhifang Li Lei Wang Advanced Research Institute and School of Pharmaceutical Sciences Taizhou UniversityJaojiangZhejiang318000China College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of EducationHangzhou Normal UniversityHangzhouZhejiang 311121China

Comprehensive Summary Catalytic and green strategies for the synthesis of privileged scaffolds are synthetically *** now report a radical-polar crossover(RPC)-enabled three-component cyclization of bromodifluoroalkyls with enaminones and 6-aminouraciles via a visible-light-induced domino *** reaction exhibited a broad substrate scope(>40 examples)including complex molecules,which highlighted the utility of this strategy for the construction of a library of bioactive analogs.

关键词： Photocatalysis Heterocycles Radicals Bromodifluoroalkyls 6-Aminouraciles Enaminones

Effect of hot extrusion process on microstructure and mechanical properties of hypereutectic Al-Si alloys

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China Foundry 2011年第1期8卷 145-149页

作者： Li Runxia yu Fuxiao zuo Liang Shenyang University of Technology Shenyang 110178 China Northeastern University Shenyang 110819 China

The hypereutectic Al-Si alloy was fabricated by hot extrusion process after solidified under electromagnetic stirring,and the microstructure and mechanical properties of the alloy were *** results show that the ultimate tensile strength and elongation of the alloy reached 229.5 MPa and 4.6%,respectively with the extrusion ratio of 10,and 263.2 MPa and 5.4%,respectively with extrusion ratio of *** indicates that the mechanical properties of the alloy are obviously improved with the increase of extrusion *** hot extruded,the primary Si,eutectic Si,Mg2Si,AlNi,Al7Cu4Ni and Al-Si-Mn-Fe-Cr-Mo phases are refined to different extent,and the efficiency of refinement is obvious more and more with the increase of extrusion *** T6 heat treatment,the sharp corners of these phases become passivated and roundish,and the mechanical properties are *** ultimate tensile strength of the extruded alloy after T6 heat treatment reaches 335.3 MPa with extrusion ratio of 10 and 353.6 MPa with extrusion ratio of 20.

关键词： hypereutectic Al-Si alloy electromagnetic stirring hot extrusion process primary Si phase

Evaluation of Typhoon Waves Simulated by Wave Watch-Ⅲ Model in Shallow Waters Around Zhoushan Islands

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Journal of Ocean University of China 2019年第2期18卷 365-375页

作者： sheng Yexin SHAO Weizeng LI Shuiqing ZHANG yuming YANG Hongwei zuo Juncheng Marine Science and Technology College Zhejiang Ocean University Institute of Oceanology Chinese Academy of Sciences Laboratory for Ocean Dynamics and Climate Qingdao National Laboratory for Marine Science and Technology National Marine Environmental Monitoring Center State Oceanic Administration Shandong University of Science and Technology

In this study, we simulated typhoon waves in the shallow waters around the Zhoushan Islands using the WaveWatch-Ⅲ(WW3) model version 5.16, the latest version released by the National Oceanic and Atmospheric Administration. Specifically, we used in-situ measurements to evaluate the performance of seven packages of input/dissipation source terms in the WW3 model. We forced the WW3 model by wind fields derived from a combination of the parametric Holland model and high-resolution European Center for Medium-Range Weather Forecasts(ECMWF) wind data in a 0.125? grid, herein called H-E winds. We trained the H-E winds by fitting a shape parameter B to buoy-measured observations, which resulted in a smallest root mean square error(RMSE) of 3 m s^(-1) for B, when treated as a constant 0.4. Then, we applied the seven input/dissipation terms of WW3, labelled ST1, ST2, ST2+STAB2, ST3, ST3+STAB3, ST4, and ST6, to simulate the significant wave height(SWH) up to 5 m during typhoons Fungwong and Chan-hom around the Zhoushan Islands. We then compared the SWHs of the simulated waves with those measured by the in-situ buoys. The results indicate that the simulation using ST2 performs best with an RMSE of 0.79 m for typhoon Fung-wong and an RMSE of 1.12 m for typhoon Chan-hom. Interestingly, we found the simulated SWH results to be relatively higher than those of the observations in the area between Hangzhou Bay and the Zhoushan Islands. This behavior is worthy of further investigation in the future.

关键词： waves typhoon WaveWatch-Ⅲ Zhoushan Islands

Effect of the Proportion of Bamboo Scraps on the Properties of Bamboo Scraps/Magnesium Oxychloride Composites

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Journal of Renewable Materials 2021年第10期9卷 1729-1739页

作者： Long Zheng Yiqiang Wu Shu Wang Guoan sheng Baorong Sun Yingfeng zuo College of Materials Science and Engineering Central South University of Forestry and TechnologyChangsha410004China

This study was designed to solve the problem of large waste volume from bamboo processing residues in recent *** magnesium oxychloride(MO)cementitious material as the main material and bamboo residue(BR)as the reinforcing material,a BR/MO composite material was *** effects of BR amount on the molding properties,mechanical strength,and water resistance of BR/MO composites were examined and *** electron microscopy(SEM),X-ray diffractometry(XRD),and thermogravimetric analysis were used to characterize composite microscopic morphology,crystalline structure,and heat *** results showed that,when the BR content was 1.00%(by wt),the flowability of MO paste was beneficial to composite *** mechanical properties and water resistance were greatly affected by BR *** the BR content was 1.00%,composite compressive and bending strengths and softening coefficient all reached maximum ***,increases in water absorption by 24 h and decreases of contact angle were *** results suggested that,when the BR content was 1.00%,composite mechanical properties and water resistance were the best and the mechanical strength also improved with extended composite storage *** analysis indicated that BR played the role of a reinforcing phase in MO ***,when the BR content exceeded 1.00%,interfacial bonding between BR and MO became *** analysis showed that,with 1.00%BR content,composites showed more 5-phase crystals with high *** further explained the reason why this composite’s mechanical properties were the best and the heat resistance not deteriorated due to BR,which was easily decomposed.

关键词： Bamboo scraps magnesium oxychloride cementation mechanical properties water resistance interface bonding crystal structure