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Chinese Chemical Letters 2022年第4期33卷 1798-1816页

作者： Daoshan Yang Qiuli Yan Enjie Zhu Jian Lv Wei-min he Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOEState Key Laboratory Base of Eco-Chemical EngineeringCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

The development of green and convenient methods for C–S bond formation has received significant attention because C–S bond widely occurs in many important pharmaceutical and biological ***, visible-light photoredox catalysis has been established as an efficient and general tool for the construction of C–C and C-heteroatom bonds. In this review, we have focused on the research on recent advances in C–S bond formation via visible-light photoredox catalysis, and the growing opportunities they present to the construction of complex chemical scaffolds for applications encompassing bioactive molecules synthesis, synthetic methodology development, and sulfur-containing drugs. We hope that this review will provide chemists with a synthetic tool that will open the door to further development of organsulfur chemistry.

关键词： Visible light C-S bond formation Radical Cyclization Sulfur-containing compouds

Effect of filler on the self-lubrication performance of graphite antimony composites

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Journal of China University of mining and Technology 2008年第3期18卷 441-443,448页

作者： WANG Qi-li HU Ya-fei he min School of Chemical Engineering ＆ Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Mechanical ＆ Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Mechanical ＆ Electrical Engineering Xuzhou Institute of Technology Xuzhou Jiangsu 221008 China

Graphite antimony composites were prepared using a mechanical pressure infiltration method to force molten antimony into graphite preforms having a percolation micro-structure and a hop-pocket power filler. The micro-structural and macroscopic properties of the graphite antimony composites were analysed. Observations included metallographic analysis, physical properties and friction and wear behaviour. The results show that the wear loss is decreased by 12.24% and that the friction coefficient is re-duced by 32.61% after hop-pocket power was used. The research indicates that the hop-pocket power method gives a useful way to reduce friction coefficients and wear loss, and to increase service life and self-lubrication properties, of the graphite antimony seal-ing material as compared to carbon black.

关键词： graphite/antimony composites infiltration self-lubrication performance filler

Research on Percolation Network and Physical Properties of Graphite/Antimony Composites

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Journal of China University of mining and Technology 2006年第2期16卷 189-192页

作者： HU Ya-fei he min WANG Qi-li School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Materials Science and Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The microstructure, friction and wear behaviour of graphite preform and graphite/antimony composites are analysed based on the percolation theory of hydrodynamics to investigate the relationship between the percolation net- work and physical properties of graphite/antimony composites. The result shows that there are two important factors to enhance friction and wear behaviour of graphite/antimony composites at high temperature: 1) the formation of the pore network in the preform, which is called the first percolation and 2) the optimization of infiltration method in the process of infiltrating antimony, which is called the second percolation. By adding some pyrolysate and controlling the roasting process, perfect net pores and sub-micron percolation microstructure may be formed in the graphite preform. By con- trolling the infiltration process, the saturation of molten antimony infiltrating into perfect pores can be optimized.

关键词： graphite antimony-infiltrating percolation pore friction and wear behaviour

Chemical constituents and antibacterial activities of Aspidistra typica

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Chinese Journal of Natural Medicines 2018年第6期16卷 465-470页

作者： LIANG Xiao-Xia KONG Lin-Xi FEI Wen-Bo he min Natural Medicine Research Center College of Veterinary Medicine Sichuan Agricultural University

In the present investigation, we carried a phytochemical study of an ethanol-soluble extract from the root barks of Aspidistra typica Baill., a traditional food and herb medicine, leading to the isolation of four different kinds of compounds, including one benzene substituted coumarin, two organic phosphonic compounds, and one xanthone. The novel benzene substituted coumarin typicacoumarin A(1) was a new type of coumarin, and the two new organic phosphonic compounds, typicalphosphine A(2) and typicalphosphine B(3) were isolated for the first time, and their structures were elucidated by spectral techniques, viz.1 D, 2 D NMR spectra and HR-ESI-MS. The xanthone compound typicaxanthone A(4) was discovered from nature for the first time. The two new organic phosphonic chlorides(2, 3) showed stronger antibacterial activities, which were comparable to berberine hydrochloride. And typicaxanthone A(4) showed much stronger antibacterial activity against Escherichia coli ATCC-25922 bacterial strain, while typicacoumarin A(1) showed moderate antibacterial activities, weaker than berberine hydrochloride.

关键词： Aspidistra typica Benzene substituted coumarin Organic phosphonic compounds Xanthone Antibacterial activity

MicroRNA-155 Regulates Inflammatory Cytokine Production in Tumor-associated Macrophages via Targeting C/EBPβ

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Cellular & Molecular Immunology 2009年第5期6卷 343-352页

作者： min he Zhenqun Xu Tong Ding Dong-ming Kuang Limin Zheng Key Laboratory of Gene Engineering of the ministry of Education StateKey Laboratory of Biocontrol School of Life Sciences Sun Yat-SenUniversity Guangzhou China School of Life Sciences Sun Yat-Sen University Guangzhou 510275 China

Macrophages （Mφ） are prominent components of solid tumors and exhibit distinct phenotypes in different microenvironments. We have recently found that tumors can alter the normal developmental process of Mφ to trigger transient activation of monocytes, but the underlying regulatory mechanisms are incompletely understood. here, we showed that the protein expression of transcription factor C/EBPβ was markedly elevated in tumor-associated Mφ both in vitro and human tumors in situ. The expression of C/EBPβ protein correlated with cytokine production in tumor-activated monocytes. Moreover, we found that C/EBPβ expression was regulated at the post-transcriptional level and correlated with sustained reduction of microRNA-155 （miR-155） in tumor-activated monocytes. Bioinformatic analysis revealed that C/EBPβ is a potential target of miR-155 and luciferase assay confirmed that C/EBPβ translation is suppressed by miR-155 through interaction with the 3＇UTR of C/EBPβ mRNA. Further analysis showed that induction of miR-155 suppressed C/EBPβ protein expression as well as cytokine production in tumor-activated monocytes, an effect which could be mimicked by silencing of C/EBPβ. These results indicate that tumor environment causes a sustained reduction of miR-155 in monocytes/Mφ, which in turn regulates the functional activities of monocytes/Mφ by releasing the translational inhibition of transcription factor C/EBPβ.

关键词： C/EBPβ inflammatory cytokine miR-155 TAM transcription factor

Morphology and Mechanical Properties of Nylon 6/PBT Blends Compatibilized with Styrene/Maleic Anhydride Copolymer

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Chemical Research in Chinese Universities 2007年第6期23卷 726-732页

作者： QIN Shu-hao YU Jie ZheNG Qiang he min ZHU Hong Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 P. R. China National Engineering Research Center for Compounding and Modification of Polymeric Materials Guiyang 550025 P. R. China

The mechanical properties and dynamic mechanical properties of blends composed of Nylon 6 and poly （ butylenes terephthalate）（PBT）, with styrene/maleic anhydride（SMA） as compatibilizer, were studied. The observation on the morphologies of the etched surfaces of the cryogenically fractured specimens via scanning electron microscopy（SEM） demonstrated that in the compatibilized Nylon 6/PBT blends, there exists a finer and more uniform dispersion induced by the in-situ interfacial chemical reactions during the preparation than that in the corresponding uncompatibilized blends. On the other hand, the overall mechanical properties of the compatibilized blends could be remarkably im- proved compared with those of the uncompatibilized ones. Moreover, increasing the amount of the compatibilizer SMA leads to a more efficient dispersion of the PBT phase in Nylon 6/PBT blends. Furthermore, there exists an optimum level of SMA added to achieve the maximum mechanical properties. As far as the mechanism of this reactive compatibilization is concerned, the enhanced interfacial adhesion is necessary to obtain improved dispersion, stable phase morphology, and better mechanical properties.

关键词： Nylon-6 PBT Morphology Dynamic mechanical property

Thermal Expansion Behavior of Poly(amide-imide)Films with Ultrahigh Tensile Strength and Ultralow CTE

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Chinese Journal of Polymer Science 2020年第7期38卷 748-758,I0007页

作者： Lan Bai Lei Zhai min-Hui he Chang-Ou Wang Song Mo Lin Fan Laboratory of Advanced Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

A series of novel poly(amide-imide)(PAl)films with different amide contents were prepared from pyromellitic dianhydride and four amide-containing *** PAl films exhibited excellent mechanical and thermal properties with tensile strength of 203.7-297.4 MPa and Tg above 407℃.The rigid backbone structures combined with strong intermolecular interactions provided PAl films with ultralow in-plane CTE values from-4.17 ppm/℃to-0.39 ppm/℃in the temperature range of 30-300℃.The correlation between thermal expansion behavior and aggregation structures of PAl film was *** results suggested that hydrogen bonding interactions could be maintained even at high temperature,thus resulting in good dimension reversibility of films in multiple heating-cooling *** is demonstrated that dimensional stabilities of PAl films are determined by the rigidity,orientation,and packing of molecular ***-resistant PAl films with ultralow CTE can be developed as flexible substrates by regulating backbones and aggregation structures for optoelectronic application.

关键词： Poly(amide-imide)s Thermal expansion behavior Aggregation structures

3D printed ultra-fast photothermal responsive shape memory hydrogel for microrobots

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International Journal of Extreme Manufacturing 2022年第1期4卷 109-118页

作者： Ziheng Zhan Lei Chen Huigao Duan Yiqin Chen min he Zhaolong Wang National Research Center for High-Efficiency Grinding College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082People’s Republic of China College of Electrical and Information Engineering Hunan UniversityChangsha 410082People’s Republic of China

Hydrogels with stimuli-responsive capabilities are gaining more and more attention nowadays with prospective applications in biomedical engineering,bioelectronics,microrobot,*** develop a photothermal responsive hydrogel based on N-isopropylacrylamide that achieved a fast and reversible deformation manipulated only by near-infrared(NIR)*** hydrogel was fabricated by the projection micro stereolithography based 3D printing technique,which can rapidly prototype complex 3D ***,with the variation of the grayscale while manufacturing the hydrogel,the deformation of the hydrogel structure can be freely tuned within a few seconds by losing and absorbing water through adjusting the intensity and the irradiation direction of the NIR light,showing a potential application in ultra-fast object grabbing and *** present study provides a new method for designing ultrafast photothermal responsive hydrogel based microrobot working in water.

关键词： hydrogel 3D printing photo-thermal response shape memory microrobot

Fighting the enemy: How rice survives the blast pathogen's attack

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The Crop Journal 2021年第3期9卷 543-552页

作者： Junjie Yin Lijuan Zou Xiaobo Zhu Yuyan Cao min he Xuewei Chen State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Sichuan Agricultural University at WenjiangChengdu 611130SichuanChina Ecological Security and Protection Key Laboratory of Sichuan Province Mianyang Normal UniversityMianyang 621000SichuanChina

Global food security is threatened by rice blast disease caused by the filamentous fungus Magnaporthe *** understanding of rice resistance mechanisms is fundamental to developing strategies for disease *** this review,we summarize recent advances in pathogen-associated molecular pattern-triggered immunity,effector-triggered immunity,defense regulator-mediated immunity,and effects of nutrient elements on rice blast *** outline strategies used for breeding rice cultivars with improved disease *** also present the major research challenges for rice blast disease resistance and propose approaches for future investigation.

关键词： Blast fungus Resistance mechanism Immunity Rice breeding

Microstructure characteristics and thermodynamic properties of A357-SiCp/A357 layered composites prepared by semi-solid vacuum stirring suction casting

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China Foundry 2023年第2期20卷 108-114页

作者： Zhen-lin Zhang Ying Xiao Jun Xu Feng-liang Tan Li Wang min he Hunan Province Aluminum Alloy Semi-solid Forming Engineering Technology Research Center Loudi 417000HunanChina Hunan University of Humanities Science and TechnologyLoudi 417000HunanChina

A357-SiCp/A357 layered composites were prepared using a semi-solid vacuum stirring suction casting *** microstructures,mechanical properties,and thermal conductivities of the composites fabricated under different suction casting processes were ***,the microstructural evolution characteristics and performance enhancement mechanism of the A357-SiCp/A357 layered composites were *** results demonstrate that suction casting at 610°C with a low solid phase ratio can significantly enhance the material density and reduce the agglomeration of *** A357-SiC_(p)/A357 interface is clear and straight with good *** an increase in the suction casting temperature,the bending resistance and thermal conductivity of the A357-SiC_(p)/A357 layered composites exhibit a trend of significantly increase at first and then slowly decrease owing to casting defects,interface bonding,and SiCp *** with SiCp/A357 composites,the bending strength,deflection,and thermal conductivity of the A357-SiCp/A357 layered composites increase from 257 MPa,1.07 mm,and 155.72 W·(m·K)^(-1) to 298 MPa,2.1 mm,and 169.86 W·(m·K)^(-1),*** study provides a reference for improving the rheological casting of aluminum matrix layered composites.

关键词： semi-solid vacuum stirring suction casting SiCp/A357 layered composites thermodynamic properties rheological casting