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Chinese Chemical Letters 2017年第8期28卷 1631-1639页

作者： Jing Liu qi-wei chen Kai Wu College of Chemistry and Chemical Engineering Liaoning Normal University BNLMS College of Chemistry and Molecular Engineering Peking University

Bottom-up approach to constructing low-dimensional nanostructures on surfaces with terminal alkynes has drawn great interest because of its potential applications in fabricating advanced functional nanomaterials. The diversity of the achieved products manifests rich chemistry of terminal alkynes and hence careful linking strategies and proper controlling methodologies are required for selective preparations of high-quality target nanoarchitectures. This review summarizes various on-surface linking strategies for terminal alkynes, including non-bonding interactions as well as organometallic and covalent bonds, and presents examples to show effective control of surface assemblies and reactions of terminal alkynes by variations of the precursor structures, substrates and activation modes. Systematic studies of the on-surface linkage of terminal alkynes may help efficient and predictable preparations of surface nanomaterials and further understanding of surface chemistry.

关键词： Terminal alkynes On-surface reactions Surface assemblies Scanning tunneling microscopy Low-dimensional nanostructures

In vitro corrosion of pure magnesium and AZ91 alloy—the influence of thin electrolyte layer thickness

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Regenerative Biomaterials 2016年第1期3卷 49-56页

作者： Rong-Chang Zeng wei-chen qi Fen Zhang Shuo-qi Li College of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

In vivo degradation predication faces a huge challenge via in vitro corrosion test due to the difficulty for mimicking the complicated microenvironment with various influencing factors.A thin electrolyte layer(TEL)cell for in vitro corrosion of pure magnesium and AZ91 alloy was presented to stimulate the in vivo corrosion in the micro-environment built by the interface of the implant and its neighboring *** results demonstrated that the in vivo corrosion of pure Mg and the AZ91 alloy was suppressed under TEL *** AZ91 alloy was more sensitive than pure Mg to the inhibition of corrosion under a TEL thickness of less than 200 *** TEL thickness limited the distribution of current,and thus localized corrosion was more preferred to occur under TEL condition than in bulk *** TEL cell might be an appropriate approach to simulating the in vivo degradation of magnesium and its alloys.

关键词： magnesium corrosion thin electrolyte layer biomaterials

Efficient synthesis of panaxadiol derivatives using continuous-flow microreactor and evaluation of anti-tumor activity

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Chinese Chemical Letters 2015年第3期26卷 334-338页

作者： Yan Wu wei-qi chen Yu-qing Zhao Hu-Ri Piao Key Laboratory of Natural Resources and Functional Molecules of the Changbai Mountain Affiliated Ministry of EducationYanbian University College of Pharmacy Department of Chemistry Fudan University School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University

An efficient method has been developed for the synthesis of a series of（20R）-panaxadiol derivatives（4a–w） using a continuous-flow *** antitumor activities of the newly synthesized compounds were evaluated in vitro in two human prostate adenocarcinoma tumor cell lines（i.e.,PC-3and LNCa P cells）,and their cytotoxicities were evaluated using a standard MTT *** 4c,4h,4p,4q and 4s exhibited higher antitumor activities toward PC-3 cell line than panaxadiol,which was used as a reference standard.

关键词： antitumor adenocarcinoma toward silica batch shorter spectrometer incubated equiv acetate

In vitro degradation of MAO/PLA coating on Mg-1.21Li-1.12Ca-1.0Y alloy

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Frontiers of Materials Science 2014年第4期8卷 343-353页

作者： Rong-Chang ZENG wei-chen qi Ying-wei SONG qin-Kun HE Hong-Zhi CUI En-Hou HAN College of Materials Science and Engineering Shandong University of Science and Technology Qingdao 266590 China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology Qingdao 266590 China National Engineering Center for Corrosion Control Institute of Metals Research Chinese Academy of Sciences Shenyang 110016 China

Magnesium and its alloys are promising biomaterials due to their biocompatibility and osteoinduction. The plasticity and corrosion resistance of commercial magnesium alloys cannot meet the requirements for degradable biomaterials completely at present. Particularly, the alkalinity in the microenvironment surrounding the degradation, implants, resulting from the arises a major concern. Micro arc oxidation （MAO） and poly（lactic acid）（PLA） composite （MAO/PLA）coating on biomedical Mg- 1.21Li-1.12Ca-1.0Y alloy was prepared to manipulate pH variation in an appropriate range. Surface morphologies were discerned using SEM EMPA. AM corrosion resistance was evaluated via electrochemical Polarization and impedance and hydrogen volumetric method. The results demonstrated that the MAO coating predomlnantly consisted of MgO, Mg2SiO4 and YzO3. The composite coating markedly improved the corrosion resistance of the alloy. The rise in solution pH for the MAO/PLA coating was tailored to a favorable range of 7.5-7.8 The neutrallzation caused by the alkalinity of MAO and Mg substrate and acidification of PLA was probed. The reSult designates that MAOI PLA composite coating on Mg-1.21Li-1.12Ca-1.0Y alloys may be a promising biomedical coating.

关键词： magnesium alloy micro.arc oxidation (MAO) poly(lactic acid)(PLA) biomaterial degradation

Bilateral congenital uveal coloboma concurrent with retinal detachment

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International Journal of Ophthalmology(English edition) 2022年第2期15卷 364-366页

作者： Zi-Jing Huang Jing-Sheng Yi wei-qi chen Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong Shantou 515041Guangdong ProvinceChina

Dear Editor,We are writing to present a bilateral uveal coloboma concurrent with retinal detachment(RD)in a 16-year-old *** are rare,congenital and potentially blinding malformations caused by incomplete closure of em... 详细信息

关键词： incomplete closure concurrent

Surgical treatment for proliferative diabetic retinopathy with ocular albinism

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International Journal of Ophthalmology(English edition) 2023年第3期16卷 479-482页

作者： Zi-Jing Huang Ding-Guo Huang wei-qi chen Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong Shantou 515041Guangdong ProvinceChina

Dear Editor,We are writing to present an uncommon case of a45-year-old woman with bilateral proliferative diabetic retinopathy (PDR) and ocular albinism (OA).Albinism is a group of inherited disorders of tyrosinase ac... 详细信息

关键词： ocular proliferative diabetic

Advances in coatings on biodegradable magnesium alloys

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Journal of Magnesium and Alloys 2020年第1期8卷 42-65页

作者： Zheng-Zheng Yin wei-chen qi Rong-Chang Zeng Xiao-Bo chen Chang-Dong Gu Shao-Kang Guan Yu-Feng Zheng Corrosion Laboratory for Light Metals College of Materials Science and EngineeringShandong University of Science and TechnologyQingdao 266590China Department of Orthopaedics and Traumatology Li KaShing Faculty of MedicineThe University of Hong KongHong Kong 999077China School of Engineering RMIT UniversityCarltonVIC 3053Australia School of Materials Science and Engineering State Key Laboratory of Silicon MaterialsZhejiang UniversityHangzhou 310027China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China State Key Laboratory for Turbulence and Complex Systems and Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing 100871China

The clinic applications of bioabsorbable magnesium(Mg)and its alloys have been significantly restricted owing to their poor corrosion *** elemental alloying,surface modification and functionality is a major approach to increasing corrosion resistance for magnesium *** article reviews the cutting-edge advances and progress of biodegradable surface coatings upon Mg alloys over the last decades,aims to build up a knowledge framework of surface modification on biodegradable Mg alloys.A considerable number of conversion,deposition,mechanical and functional coatings and their preparation methods are *** emphasis has been placed on the composition of chemical conversion and deposited coatings to overcome the disadvantages of adhesion,corrosion resistance and biocompatibility of a single coating for biomedical *** issues have been addressed on the integration of the structural and functional factors of the composite coatings.

关键词： Magnesium alloy Biomaterial Corrosion resistance Coating Biodegradability

Visual impact of sub-Tenon anesthesia during combined phacoemulsification and vitrectomy surgery

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International Journal of Ophthalmology(English edition) 2014年第5期7卷 860-863页

作者： wei-qi chen Vishal Jhanji Hao-Yu chen Gui-Hua Zhang Ping Hou Joint Shantou International Eye Center Shantou University and the Chinese University of Hong Kong Department of Ophthalmology and Visual Sciences the Chinese University of Hong Kong

AIM:To investigate the visual impact of sub-Tenon anesthesia during combined phacoemulsification and vitrectomy ***:In this prospective case series, consecutive patients who underwent combined phacoemulsification and pars plana vitrectomy(PPV) under sub-Tenon anesthesia between October 2008 and September 2009 were enrolled. The patients were asked whether they could see the light of the operating microscope or not between various surgical steps with their contralateral eye being ***:A total of 163 eyes of 163 patients were enrolled in this study. After their contralateral eyes were covered, 152(93.3%) patients said that they could not see any light at least during one of the surgical steps. All eyes recovered to at least light perception on the first postoperative day. The incidence of no light perception during the surgery was not related to demographic factors, including age, gender, or type of ocular ***:The incidence of no light perception during combined phacoemulsification and vitrectomy under sub-Tenon anesthesia was high in our *** should be duly informed about this temporary but potential intraoperative event.

关键词： visual impact sub-Tenon anesthesia phacoemulsification vitrectomy

Pinning-down molecules in their self-assemblies with multiple weak hydrogen bonds of C-H···F and C-H···N

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Chinese Chemical Letters 2017年第3期28卷 525-530页

作者： Xin Jin Jacob R. Cramer qi-wei chen Hai-Lin Liang Jian Shang Xiang Shao wei chen Guo-qin Xu Kurt V. Gothelf Kai Wu BNLMS College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Danish-Chinese Centre for Self-Assembly and Function of Molecular Nanostructures on Surfaces at iNANO Department of Chemistry Aarhus University8000 Aorhus C Denmark Department of Chemical Physics School of Chemistry and Materials Science University of Science and Technology of China Hefei 230026 China Department of Chemistry National University of Singapore117543 Singapore SPURc I CREATE Way #15-01CREATE Tower 138602 Singapore

Two-dimensional self-assemblies of four partially fluorinated molecules, 1,4-bis（2,6-difluoropyridin-4-yl）benzene, 4,4＇-bis（2,6-difluoropyridin-4-yl）-1,1＇-biphenyl, 4,4＇-bis（2,6-difluoropyridin-4-yl）-1,1＇：4＇,1＇-terphenyl and 4,4＇-bis（2,6-difluoropyridin-3-yl）-1,1＇-biphenyl, involving weak intermolecular C-H···F and C-H···N hydrogen bonds were systematically investigated on Au（111） with low-temperature scanning tunneling microscopy. The inter-molecular connecting modes and binding sites were closely related to the backbones of the building blocks, i.e., the molecule length determines its binding sites with neighboring molecules in the assemblies while the attaching positions of the N and F atoms dictate its approaching and docking angles. The experimental results demonstrate that multiple weak hydrogen bonds such as C-H···F and C-H···N can be efficiently applied to tune the molecular orientations and the self-assembly structures accordingly.

关键词： Fluorinated pyridyl molecules Grouped hydrogen bonds Molecular self-assembly Molecular design Scanning tunneling microscopy

Partitioning of nitrogen atoms and its effect on retained austenite content in an ultra-low-carbon Cr-Mn-N stainless steel

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Journal of Iron and Steel Research International 2021年第8期28卷 1030-1036页

作者： Zhe Zhu Wan-tang Fu Rong-bin Li qi-wei chen Ze-an Zhou Zhen-hua Wang Jia-qing Liu Shu-hua Sun State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina Shanghai Engineering Research Center of Hot Manufacturing Shanghai Dianji UniversityShanghai 201306China School of Science Yanshan UniversityQinhuangdao 066004HebeiChina

The partitioning of nitrogen atoms and its effect on the retained austenite content(RAC)during quenching and partitioning(Q&P)process were investigated by dilatometry,X-ray diffraction,and field emission transmission electron microscopy with energy-dispersive spectrometer mapping in a 00Cr13Mn8N *** partitioning by diffusion of N atoms from martensite to austenite occurred at 400℃after quenching.N atoms are enriched in austenite after partitioning,and the stability of these N-rich austenite is improved and retained at room temperature during subsequent *** different quenching temperatures(QTs)result in different phase fractions after *** the increase in QT,RAC first increases and then decreases,and the maximum RAC is 28.5 vol.%after quenching at 80℃.A mathematical model was developed to rapidly and accurately characterize the phase fraction in Q&P process based on the relative length change of the samples partitioned after quenching at different QTs.

关键词： Nitrogen partitioning Quenching and partitioning Retained austenite Energy-dispersive spectrometer mapping Dilatometry Ultra-low-carbon stainless steel