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Bimolecular reduction of carbon dioxide: double synthons for alkynes trifunctionalization

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Science China Chemistry 2024年第3期67卷 841-847页

作者： Wenfang Xiong Xiaobin Tan Hongjian liu Baiyao Zhu Jinwu Zhao jianxiao li Chaorong Qi Huanfeng jiang School of Pharmacy Guangdong Medical UniversityDongguan 523808China Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China

Carbon dioxide reduction, as a sustainable and versatile strategy for the access of chemical fuels, has attracted increasing attention and enormous efforts have been devoted to it in recent years. However, employing carbon dioxide as double synthons via bimolecular reduction remains challenging. Here, by leveraging the bimolecular reduction of carbon dioxide to carbonyl and methyl respectively, we describe a Pd-catalyzed trifunctionalization of alkynes with aryl iodide for the first time and showcase its advantages on the formation of various β-diketones and their application in the constructing of heterocyclic compounds with important biological activity, including pyrimidine, oxazole, pyrazole.

关键词： carbon dioxide bimolecular reduction trifunctionalization double synthons

Numerical model establishment and verification of cold pilgering on cycle feed rate

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Journal of Iron and Steel Research International 2018年第4期25卷 398-408页

作者： Zhi-bing Chu Dong Wei lian-yun jiang Duo Zhang Qing-xue Huang Yu-gui li Heavy Machinery Engineering Research Center of Ministry of Education Taiyuan University of Science and Technology Taiyuan 030024 Shanxi China Shanxi Provincial Key Laboratory of Metallurgical Device Design Theory and Technology Taiyuan University of Science and Technology Taiyuan 030024 Shanxi China

A numerical model was established to calculate the cycle feed rate through studying the case of a cold pilger mill with the 304 stainless steel pipe. Firstly, the precise constitutive equation of 304 stainless steel was obtained through nonlinearly fitting the true stress-strain data from unidirectional tensile test. Then, the numerical method to calculate the equivalent deformation was determined according to the plastic deformation feature of the steel tube during cold rolling and the incremental theory. Finally, the cycle feed rate of cold roiled 304 stainless steel pipe was extracted when formulating springback through utilizing above results comprehensively and unloading law. Stress state, metal flow, finished pipe size and distribution of residual stress were obtained by finite element method to calculate the whole rolling process when the cycle feed rate was 10 mm, and the optimized model was verified through finished pipe size.

关键词： Cycle feed rate Cold pilgering 304 stainless steel pipe Constitutive relationship Incremental theory Unloading law Residual stress experiment

Chloride Assisted Growth of Aluminum Nitride Nanobelts and Their Enhanced Dielectric Responses

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Chinese Journal of Chemical Physics 2008年第6期21卷 586-590页

作者： Ting Xie Min ye Zhi jiang Yong Qin Yu-cheng Wu Guo-wen Meng li-de Zhang Institute of Tribology Hefei University of Technology Hefei 230009 China Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

Aluminum nitride （AlN） nanobelts were successfully synthesized in high yield through a chloride assisted vapor-solid process. X-ray diffraction, transmission electron microscopy, and selected area electronic diffraction demonstrate that the as-prepared nanobelts are pure, structurally uniform and single crystalline, and can be indexed to hexagonal wurtzite structure. The micro observations show that there exist no defects in the obtained nanobelts. The growth direction of the nanobelts is along [0001]. The frequency spectra of the relative dielectric constant and of the dielectric loss were measured in the frequency range of 50 Hz to 5 MHz. Analysis of these spectra indicates that the interface in samples has great influence on the dielectric behavior of samples. As compared with AlN micropowders, AlN nanobelts have much higher relative dielectric constant, especially at low frequencies at room temperature.

关键词： Aluminum nitride Nanobelt Chloride assisted growth Dielectric property

Analysis of total reaction cross sections for deuterons on 1p-shell-nuclei

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Science China(Physics,Mechanics & Astronomy) 2018年第11期61卷 30-35页

作者： YiDi Chen Yun Zhang jianling Lou DanYang Pang Yanlin Ye Wei liu Ying jiang Gen li School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University School of Physics and Nuclear Energy Engineering Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang University

This study aims to analyze the differential cross sections （DCSs） of elastic scattering and total reaction cross sections （TRCSs） of the loosely-bound deuteron projectile impinging on lp-shell nuclei, such as 9Be, 12C, and 160, at incident energies ranging between 10.6 and 171 MeV using the continuum discretized coupled channel （CDCC） method. By fitting the experimental data for the DCSs and TRCSs, energy-dependent renormalization factors for the real and imaginary parts of the nucleon-nucleus optical-model potentials deduced from the studies proposed by Koning and Delaroche （KD02） and by Watson, Singh, and Segel （WSS）, are obtained. It is found that with the WSS potential, which was obtained specifically for lp-shell nuclei, the CDCC calculations can simultaneously reproduce both the DCSs and the TRCSs. The results show that it is important to choose appropriate optical potentials to describe deuteron-induced reactions.

关键词： total reaction cross sections differential cross sections deuteron 1p-shell nuclei

PPCPs in a drinking water treatment plant in the Yangtze River Delta of China: Occurrence,removal and risk assessment

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Frontiers of Environmental Science & Engineering 2019年第2期13卷 133-145页

作者： Xinshu jiang Yingxi Qu liquan liu Yuan He Wenchao li Jun Huang Hongwei Yang Gang Yu School of Environment Beijing Key Laboratory for Emerging Organic Contaminants ControlTsinghua UniversityBeijing 100084China Research Institute for Environmental Innovation (Suzhou) TsinghuaSuzhou 215163China

The occurrence and removal of 39 targeted pharmaceuticals and personal care products(PPCPs)from source water,through a drinking water treatment plant(DWTP)to the water supply station,were investigated around the central part of Yangtze River Delta in China using both grab sampling and continuous *** 24 of the 39 targeted PPCPs were detected in raw water,and 12 PPCPs were detected in the finished *** highest observed concentration was enrofloxacin(85.623 ng/L)in raw *** efficiencies were remarkably negative correlated with log Kow(r =– 0.777,p libration control of concentration,indicating that more soluble PPCPs are easier to remove by the combined process(prechlorination and flocculation/precipitation),the concentration level also had a great impact on the removal *** normal process in the pilot DWTP seems to be ineffective for PPCPs control,with the limited removal efficiency of less than 30% for each step: pre-chlorination,flocculation and precipitation,post-chlorination and *** were notable differences between the data from continuous sampling and grab sampling,which should be considered for different monitoring *** chlorination and the hydrolytic decomposition of PPCPs in the water supply pipe may attenuate PPCPs concentration in the pipeline *** PPCPs examined in the effluent of DWTP do not impose a potential health risk to the local consumers due to their RQ value lower than 0.00067.

关键词： PPCPs DWTP Human health risk assessment

In-situ synthesis of TiO_2 nanostructures on Ti foil for enhanced and stable photocatalytic performance

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Journal of Materials Science & Technology 2019年第4期35卷 615-622页

作者： Ke Wang Baodan liu Jing li Xiaoyuan liu Yang Zhou Xinglai Zhang Xiaoguo Bi Xin jiang School of Materials Science and Engineering University of Science and Technology of China Shenyang National Laboratory for Materials Science (SYNL) Institute of Metal Research (IMR)Chinese Academy of Sciences (CAS) School of Renewable Energy Shenyang Institute of Engineering

TiO_2 nanostructures with strong interfacial adhesion and diverse morphologies have been in-situ grown on Ti foil substrate through a multiple-step method based on conventional plasma electrolytic oxidation(PEO) technology, hydrothermal reaction and ion exchange process. The PEO process is critical to the formation of TiO_2 seeding layer for the nucleation of Na_2Ti_3O_7 and H_2Ti_3O_7 mediates that are strongly attached to the Ti foil. An ion exchange reaction can finally lead to the formation of H_2Ti_3O_7 nanostructures with diverse morphologies and the calcination process can turn the H_2Ti_3O_7 nanostructures into TiO_2 nanostructures with enhanced crystallinity. The morphology of the TiO_2 nanostructures including nanoparticles(NP), nanowhiskers(NWK), nanowires(NW) and nanosheets(NS) can be easily tailored by controlling the NaOH concentration and reaction time during hydrothermal process. The morphology, composition and optical properties of TiO_2 photocatalysts were analyzed using scanning electron microscope(SEM), X-ray diffraction(XRD), photoluminescence(PL) spectroscopy and UV–vis absorption spectrum. Photocatalytic tests indicate that the TiO_2 nanosheets calcined at 500?C show good crystallization and the best capability of decomposing organic pollutants. The decoration of Ag cocatalyst can further improve the photocatalytic performance of the TiO_2 nanosheets as a result of the enhanced charger separation efficiency. Cyclic photocatalytic test using TiO_2 nanostructures grown on Ti foil substrate demonstrates the superior stability in the photodegradation of organic pollutant, suggesting the promising potential of in-situ growth technology for industrial application.

关键词： Plasma electrolytic oxidation In-situ growth TiO2 Photocatalysis Ag co-catalyst

Synthesis and Antioxidant Properties of Novel Silybin Analogues

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Chinese Chemical Letters 2006年第4期17卷 465-468页

作者： Jing Xu GONG lin jia WENG Feng WANG Yu Bin FENG Chang Xin ZHOU Hai Bo li Yi Hang WU Xiao jiang HAO Xiu Mei WU Hua BAI Joachim STOECKIGT Yu ZHAO Department of Traditional Chinese Medicine and Natural Drug Research College of Pharmaceutical Sciences Zhejiang University Hangzhou 310031 The Key Laboratory of Chemistry of Natural Products of Guizhou Province Chinese Academy of Sciences Guiyang 550022 Zhejiang Hisun Naturelite Pharmaceutical R＆D Co. Ltd. Hangzhou 310007 Lehrstuhl für Pharmazeutische Biologie Institut für Pharmazie Johannes-Gutenberg Universitaet Mainz D-55099 Mainz Germany

Eight novel silybin analogues （7a-h） were synthesized and their antioxidant properties including the capability of scavenging superoxide anion free radicals and the inhibitory effect on DPPH free radicals were dete... 详细信息

关键词： Silybin analogues synthesis antioxidant DPPH inhibition superoxide anion free radical scavenging.

Numerical Simulation of Sea Ice and Structure Interaction Using Common Node DEM-SPH Model

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China Ocean Engineering 2023年第6期37卷 897-911页

作者： SHEN Zhong-xiang WANG Wen-qing XU Cheng-yue li Hong-bin jiang Yin liU Ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this work,a novel fluid-structure coupling method called the common node discrete element-smoothed particle hydrodynamics(DS-SPH)method is *** framework combines the principles of the common node discrete element method(DEM)and smoothed particle hydrodynamics(SPH)to construct DEM-SPH particles situated on the same *** doing so,the DEM particles can interact with the SPH particles within their support domain,enabling fluid-structure interaction(FSI).To determine the DEM microscopic parameters required for this method,uniaxial compression and three-point bending tests are conducted on sea *** verify the proposed model,we select the interaction between sea ice and structures as a case *** simulation,the model's capability of accurately depicting sea ice deformation and fracture has been *** results indicate that the inclusion of SPH particles with fluid properties in the DEM model has minimal impact on the main mechanical parameters of sea ***,it helps prevent the occurrence of particle splashing during cement ***,it is observed that the size of DEM particles and the friction between DEM particles and the structure significantly influence the macroscopic mechanical behavior of the common-node DEM-SPH ***,we compare the fracture behavior of sea ice and the ice forces acting on structures obtained from the current model with on-site measured *** agreement between the two sets of data is excellent,further validating the effectiveness of the proposed model in practical applications.

关键词： common node DEM-SPH uniaxial compression three-point bending structure-ice interaction

股骨假体对位不齐对骨质疏松患者膝关节内侧单髁置换后外侧间室结构应力的影响

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中国组织工程研究 2025年第15期29卷 3153-3158页

作者：刘蒙飞孙荣鑫姜侃新疆医科大学第六附属医院新疆维吾尔自治区乌鲁木齐市830000

背景:假体对位不齐和患者骨质情况是影响单髁置换预后的重要因素,内侧单髁置换后外侧间室骨关节炎进展是导致其高翻修率的主要并发症。因此,这将成为今后的研究热点。目的:分析不同股骨假体倾斜角度对正常骨质和骨质疏松患者内侧单髁置... 详细信息

背景:假体对位不齐和患者骨质情况是影响单髁置换预后的重要因素,内侧单髁置换后外侧间室骨关节炎进展是导致其高翻修率的主要并发症。因此,这将成为今后的研究热点。目的:分析不同股骨假体倾斜角度对正常骨质和骨质疏松患者内侧单髁置换后外侧间室结构应力的影响,并探讨骨质疏松与术后外侧间室骨关节炎的相关性。方法:使用经验证的膝关节有限元模型,建立正常骨质(M1)和骨质疏松(M2)单髁置换模型,并分别建立股骨假体倾斜模型(正常骨质组:内倾3°,6°,9°,12°、标准位置0°、外倾3°,6°,9°,12°;骨质疏松组:内倾3°,6°,9°,12°、标准位置0°、外倾3°,6°,9°,12°),共计18种工况。评估不同股骨假体倾斜角度对外侧间室半月板、胫骨软骨和股骨软骨的应力大小和分布的影响。结果与结论:①两组模型外侧间室半月板表面和胫骨软骨表面的高应力值随假体内倾角度的增加而增加,随假体外倾角度的增加而减小,相同工况下骨质疏松组半月板表面的峰值应力大于正常骨质组,但骨质疏松组胫骨软骨表面的峰值应力却小于正常骨质组;②两组模型外侧间室股骨软骨的高应力值随假体内倾和外倾角度的增加而增加,相同工况下骨质疏松组股骨软骨的峰值应力大于正常骨质组;③提示固定平台股骨假体内倾时,正常骨质和骨质疏松膝关节内侧单髁置换后外侧间室结构的应力均将增加,骨质疏松膝关节外侧间室应力增加更为明显;所以单髁置换过程中应特别注意假体安放位置,尽量避免内倾和外倾;同时,研究结果证实了骨质疏松可能会加重内侧单髁置换后外侧间室骨关节炎的进展。

关键词：膝骨关节炎骨质疏松单髁置换股骨组件生物力学