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Ni_(2)P/MoS_(2) interfacial structures loading on N-doped carbon matrix for highly efficient hydrogen evolution

Green Energy & Environment 2022年第4期7卷 829-839页

作者： Yuelong Xu Ran Wang Zhan Liu Lili Gao Tifeng Jiao Zhenfa liu State Key Laboratory of Metastable Materials Science and Technology Yanshan University438West Hebei StreetQinhuangdao066004China Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan University438West Hebei StreetQinhuangdao066004China Hebei Engineering Research Center for Water Saving in Industry Shijiazhuang050081China Institute of Energy Resources Hebei Academy of SciencesShijiazhuang050081China

Electrochemical catalysts for the hydrogen evolution reaction(HER) have attracted increasing attentions. Noble metal-free cocatalysts play a vital role in HER applications. Herein, a novel strategy to prepare a Ni_(2)P/MoS_(2) cocatalyst through a simple hydrothermal-phosphorization method was reported, and the prepared cocatalyst was then loaded on an N-doped carbon substrate with excellent conductive performance. The large surface area of the carbon substrate provided many active sites, and the interface between Ni_(2)P and MoS_(2) improved the catalytic performance for the HER. Compared with pure Ni_(2)P catalyst and MoS_(2) catalyst, the prepared Ni_(2)P/MoS_(2) cocatalyst exhibited enhanced catalytic performance. In addition, the results indicate that the prepared cocatalyst has a wide p H range and low onset potential values of 280, 350 and40 m V in acidic, phosphate-buffered saline and alkaline solutions, respectively, and the corresponding Tafel slopes are 75, 121 and 95 mV dec^(-1),respectively. Density functional theory(DFT) was adopted to calculate the hydrogen adsorption free energy(ΔG_(H)^(*)). The results showed that the interface between Ni_(2)P and MoS_(2) reduced ΔG_H^(*), which was beneficial to the adsorption of hydrogen. Present preparation of cocatalysts with unique interfaces provides a new strategy for improving the catalytic performance of HER.

关键词： MoS_(2) Ni_(2)P Hydrogen evolution Electrochemical performance Density functional theory

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Thrombotic risk stratification of coronary aneurysms in Kawasaki disease patients:the study of morphology and hemodynamics

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Chinese Medical Journal 2022年第18期135卷 2253-2255页

作者： Haoyao Cao Tinghui Zheng Da Li Jing liu Zhan Liu Liqing Peng Department of Applied Mechanics Sichuan UniversityChengduSichuan 610065China Sichuan University Yibin Park/Yibin Institute of Industrial Technology YibinSichuan 644000China Department of Radiology West China HospitalSichuan UniversityChengduSichuan 610041China

To the Editor:Coronary artery aneurysms(CAAs),one of the complications of Kawasaki disease(KD),can cause myocardial ischemia,infarction,and even sudden death.[1]Accurate thrombotic risk stratification in KD patients w... 详细信息

关键词： patients aneurysm coronary

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Regio-and Diasteroselective C-Silylation of Enolate Enabled by a β-Boronyl Group

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Chinese Journal of Chemistry 2022年第9期40卷 1028-1032页

作者： Yu liu Miao zhan Pengfei Li National Drug Clinical Trial Institution GCP Office The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShaanxi 710061China Institute of Medical Research Northwestern Polytechnical UniversityXi'anShaanxi 710072China Frontier Institute of Science and Technology Xi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi 710054China

Silyl enol ethers are often obtained when the lithium enolates are trapped with chlorosilanes.Herein,we report a general method for the regio-and diasteroselective C-silylation of enolate enabled by theβ-boronyl group.The formation of five-membered chelation intermediate is key to the C-selective silylation and anti-selectivity.The operationally simple protocol provides a general and predictable access to theα-silylated esters.The synthetic versatility of the boron-silicon bifunctional products was demonstrated by down-stream transformations.

关键词： Silylation Boron Diastereoselectivity Enolate Nucleophilic substitution

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Enhanced strength and ductility in Al-Zn-Mg-Cu alloys fabricated by laser powder bed fusion using a synergistic grain-refining strategy

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Journal of Materials Science & Technology 2022年第29期124卷 41-52页

作者： Xiaohui liu Yunzhong liu Zhiguang Zhou Qiangkun zhan National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Grain refinement is critical to surpassing the bottlenecks of inherent hot tearing of high-strength aluminum alloys fabricated by additive manufacturing(AM).In this study,a synergistic grain-refining strategy including heterogeneous nucleation,solute-driven growth restriction and nanoparticle-induced growth restriction was introduced to control the microstructure of Al-Zn-Mg-Cu alloys during the laser powder bed fusion(LPBF)process.Crack-free Al-Zn-Mg-Cu alloys with significantly refined grains were safely fabricated via LPBF by coincorporation of Ti C and TiHparticles.In-situ L1-AlTi particles were produced to promote the heterogeneous nucleation.The grain growth was restricted by adding Ti solute,while introduced TiC nanoparticles(NPs)improved the density of heterogeneous nucleation sites and blocked grain growth physically.The resultant elimination of columnar grains and hot cracks in the(1 wt.%)TiC-and(0.8 wt.%)TiH-modified Al-Zn-Mg-Cu alloy resulted in excellent ultimate tensile strength(UTS)of 593±24 MPa,yield strength(YS)of 485±41 MPa and elongation(EL)of 10.0%±2.5%under the T6 condition.This study provides new insights into improving the grain microstructure and mechanical properties of high-strength aluminum alloys during LPBF.

关键词： Grain refinement High-strength aluminum alloys Laser powder bed fusion(LPBF) Al-Zn-Mg-Cu alloy

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An Efficient Nanoparticle-Supported and Magnetically Recov-erable Copper(I)Catalyst for Synthesis of Furans from Ene-yne-ketone

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中国化学:英文版 2015年第2期33卷 175-180页

作者： Yi liu Zhan Liu Yingde Cui School of Materials Science and Engineering Northwestern Polytechnical UniversityXi'anShaanxi 710072China Departmenl of Chemistry and Chemical Engineering Huaihua UniversityHuaihuaHunan 418000China Guangzhou Vocational College of Science and Technology GuangzhouGuangdong 510550China

A magnetic nano-supported Cu(I)catalyst was prepared and showed high activity for cyclization of ene-yne-ketone to synthesize furans.The catalyst was easily recovered from the reaction by using external magnets and re... 详细信息

关键词： furans ene-yne-ketone magnetic nano-supported copper(I)catalyst cyclization

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Global Epidemic of Ebola Virus Disease and the Importation Risk into China: An Assessment Based on the Risk Matrix Method

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Biomedical and Environmental Sciences 2023年第1期36卷 86-93页

作者： SHANG Wei Jing JING Wen zhan liu Jue liu Min School of Public Health Peking UniversityBeijing 100191China

Objective To analyze the global epidemic status of the Ebola virus disease(EVD) and assess the importation risk into China.Methods Data from World Health Organization reports were used. We described the global epidemic status of EVD from 1976–2021, and assessed and ranked the importation risk of EVD from the diseaseoutbreaking countries into China using the risk matrix and Borda count methods, respectively.Results From 1976–2021, EVD mainly occurred in western and central Africa, with the highest cumulative number of cases(14,124 cases) in Sierra Leone, and the highest cumulative fatality rate(85%) in the Congo. Outbreaks of EVD have occurred in the Democratic Republic of the Congo and Guinea since 2018. The importation risk into China varies across countries with outbreaks of disease.The Democratic Republic of the Congo had an extremely high risk(23 Borda points), followed by Guinea and Liberia. Countries with a moderate importation risk were Nigeria, Uganda, Congo, Sierra Leone,Mali, and Gabon, while countries with a low importation risk included Sudan, Senegal, and Co te d’Ivoire.Conclusion China is under the risk of EVD importation with the globalization and severe epidemic status of EVD. Key attention need to be paid to the Democratic Republic of the Congo, Guinea, and Liberia. Therefore, it is necessary to prevent and prepare in advance for importation risk in China.

关键词： Ebola virus disease Infectious disease Importation risk Risk matrix method

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刘战

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世界建筑 2019年第5期 28-28,121页

作者：刘战中国建筑东北设计研究院有限公司中国建筑东北设计研究院有限公司深圳分公司

由于自幼喜欢画画,高考填志愿时父母帮我选择了建筑学专业,于是1979年我考入了哈尔滨建筑工程学院建筑系,在美丽的哈尔滨度过了难忘的4年时光。当时的建筑系规模不大,每个年级只招收一个班,老师来自全国各地,很多都是南方人,像邓林翰老... 详细信息

由于自幼喜欢画画,高考填志愿时父母帮我选择了建筑学专业,于是1979年我考入了哈尔滨建筑工程学院建筑系,在美丽的哈尔滨度过了难忘的4年时光。当时的建筑系规模不大,每个年级只招收一个班,老师来自全国各地,很多都是南方人,像邓林翰老师、侯幼彬老师、张家骥老师等,老师们严谨的学风,扎实的功底给我们留下了深刻的印象。

关键词：建筑工程学院建筑学专业建筑系哈尔滨老师南方人

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Prediction of temperature field in machined workpiece surface during the cutting of Inconel 718 coated with surface-active media

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Advances in Manufacturing 2023年第3期11卷 378-389页

作者： Qing-An Yin zhan-Qiang liu Bing Wang School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key National Demonstration Center for Experimental Mechanical Engineering Education/Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MQE Jinan 250061People's Republic of China

The heat generated and accumulated on the machined surface of an Inconel 718 workpiece causes thermal damage during the cutting process.Surface-active media with high thermal conductivity coated on the workpiece to be machined may have the potential to reduce the generation of cutting heat.In this study,a theoretical model for predicting the instantaneous machined surface temperature field is proposed for surface-active thermal conductive medium(SACM)-assisted cutting based on the finite element and Fourier heat transfer theories.Orthogonal cutting experiments were performed to verify the results predicted using the proposed surface-temperature field model.Three SACMs with various thermal conductivities were used to coat Inconel 718 surface to be machined.Thermocouples embedded into the workpiece were used to measure the cutting temperature at different points on the machined workpiece surface during the cutting process.The experimental results were in agreement with the predicted temperatures,and the maximum error between the experimental results and predicted temperatures was approximately 9.5%.The cutting temperature on the machined surface decreased with an increase in the thermal conductivity of the SACM.The graphene SACM with high thermal conductivity can effectively reduce the temperature from 542℃ to 402℃,which corresponds to a reduction of approximately 26%.The temperature reduction due to SACM decreases with an increase in the distance between the temperature prediction point and machined workpiece surface.In conclusion,the cutting temperatures on the machined workpiece surface can be reduced by coating with SACM.

关键词： Surface-active thermal conductive media(SACM) Finite element model Cutting heat Cutting temperature Inconel 718

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LADA strategy for the synthesis of unnatural amino acids and direct modifications of peptides

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Science China Chemistry 2023年第6期66卷 1788-1794页

作者： Jun-Liang Zhou Yun-Qi liu zhan-Kui Sun Shanghai Frontiers Science Center for Drug Target Identification and Drug Delivery School of Pharmaceutical SciencesShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Pharm-X CenterSchool of Pharmaceutical SciencesShanghai Jiao Tong UniversityShanghai 200240China AI Pharma Center Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai 200240China Shanghai Artificial Intelligence Laboratory Shanghai 200232China

Unnatural amino acids(UAAs)are important building blocks in organic synthesis and drug discovery.They are also frequently integrated into peptides or proteins for biological studies.However,the direct and simplified synthesis of UAAs remains a great challenge.At the same time,vast known peptide modifications are based on carbon-heteroatom bonds.There are no general methods for peptide modifications via the construction of C–C bonds.To address this challenge,herein we propose the LADA strategy,which is composed of two steps:the selective labeling and activation of cysteine residues,the desulfurization to generate carbon-centered radical and the radical addition to alkenes to build C–C bond.This one-pot protocol has obvious advantages such as good functional group tolerance,biocompatible reaction conditions,and retained stereochemistry.This strategy was successfully utilized for the synthesis of unnatural amino acids and direct modifications of peptides.

关键词： unnatural amino acids peptide modifications desulfurization cysteine radical addition

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Defining endogenous barcoding sites for CRISPR/Cas9-based cell lineage tracing in zebrafish

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Journal of Genetics and Genomics 2020年第2期47卷 85-91页

作者： Chang Ye Zhuoxin Chen Zhan Liu Feng Wang Xionglei He State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen UniversityGuangzhou510275China

There is a growing interest in developing experimental methods for tracking the developmental cell lineages of a complex organism.The recently developed CRISPR/Cas9-based barcoding method is,although highly promising,difficult to scale up because it relies on exogenous barcoding sequences that are engineered into the genome.In this study,we characterized 78 high-quality endogenous sites in the zebrafish genome that can be used as CRISPR/Cas9-based barcoding sites.The 78 sites are all highly expressed in most of the cell types according to single-cell RNA sequencing(scRNA-seq)data.Hence,the barcoding information of the 78 endogenous sites is recovered by the available scRNA-seq platforms,enabling simultaneous characterization of cell type and cell lineage information.

关键词： Zebrafish CRISPR/Cas9 Cell lineage Development Single-cell RNA sequencing

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