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Catalyst-free formal[4+1]/[4+2]cyclization cascade sequence of isocyanides with two molecules of acylketene formed in situ from thermal-induced Wolff rearrangement of 2-diazo-1,3-diketones

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Science Bulletin 2020年第8期65卷 670-677,M0004页

作者： Jian Luo guo-shu chen shu-Jie chen Yun-Lin Liu School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006Chino

An expedient and economic approach for constructing O,O,N-spiro compounds consisting of both a 1,3-oxazine and a furan ring through a catalyst-free formal[4+1]/[4+2]cycloaddition cascade sequence of isocyanides with two molecules of acylketene formed in situ through thermal-induced Wolff rearrangement of 2-diazo-1,3-diketones was *** reaction displayed good functional group tolerance and was compatible with different isocyanides and 2-diazo-1,***,preliminary asymmetric attempts of this reaction are made by utilizing optically pure isocyanides as inputs,and moderate diastereomeric induction was observed.

关键词： Catalyst-free Isocyanide Acylketene 2-Diazo-1,3-diketone Wolff rearrangement

Single-blockmeasurement for the cryogenic permanent magnet undulator sorting

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Radiation Detection Technology and Methods 2021年第1期5卷 83-89页

作者： Ling-Ling Gong Xiao-Yu Li Yu-Hui Li Ya-Jun Sun Hui-Hua Lu Ke-yun Gong Qing guo·shu-chen Sun Zhi-qiang Li Wan chen Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Purpose The magnet sorting is a standard step in the undulator fabrication *** shortest undulators period used in the High Energy Photon Source(HEPS)is only 12 *** the short period undulator,the sorting may be more important than the long-period ***,the Helmholtz measurement is used as the input for the *** is the averaged orthogonal magnetization of each *** order to investigate whether the Helmholtz coil measurement is enough for the sorting,a careful study has been *** Firstly,a magnetic camera was used to scan the 3D surface field of a ***,its field integral ismeasured by the stretched *** the measurement,the magnetwas placed at different *** results were checked to seewhether they are consistent with expected features supposing a homogeneous magnetized ***,the results measured by the Helmholtz coil and the stretched wire were *** The surface field scan demonstrates that the field over a magnet block is ***,the field integral measurement by the stretched wire also shows big difference when the different magnet sides toward *** comparison between the stretched wire and the Helmholtz coil measurement shows no *** The study presented in this paper reveals that the homogeneity of the magnetization is ***,the Helmholtz coil data are insufficient to the short-period undulators sorting.

关键词： Magnet sorting Undulator Stretched wire Helmholtz coil

Triplophysa xuanweiensis sp. nov., a new blind loach species from a cave in China(Teleostei:Cypriniformes:Nemacheilidae)

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Zoological Research 2022年第2期43卷 221-224页

作者： Zong-Min Lu Xue-Jian Li Wen-Jian Lu Jin-Qing Huang Tian-Ke Xu Gang Huang Fen-Qiong Qian Peng Yang shu-guo chen Wei-Ning Mao Ya-Hui Zhao Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China Qujing Aquaculture Station QujingYunnan 655099China Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution Shanghai Ocean UniversityShanghai 201306China Xuanwei Fisheries Management Station XuanweiYunnan 655499China School of Basic Medical Sciences Guilin Medical UniversityGuilinGuangxi 541001China

Triplophysa xuanweiensis ***.,a new blind loach species from the family Nemacheilidae,is described based on specimens collected from a subterranean river in Xuanwei City,Yunnan Province,*** new species can be distinguished from all known congeners by a combination of the following characters:eyes absent,dorsal-fin origin anterior to pelvic-fin origin,tip of pelvic fin reaching anus,dorsal fin with 7-8 branched rays,caudal fin forked with 16-18 branched rays,body scaleless and colorless,lateral line complete,and posterior chamber of air bladder well developed and connected to anterior chamber by long,slender tube.

关键词： blind bladder reaching

Enantioselective palladium-catalyzed allylic alkylation of indoles by a new class of chiral biquinolyl biphosphine ligand

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Enantioselective palladium-catalyzed allylic alkylation of i...

Synthesis of novel chiral biquinolyl biphosphine ligand and its application in Palladium-catalyzed asymmetric allylic allylations

中国化学会第九届全国有机化学学术会议

作者： Jin-Ping Lu Bin Xie guo-shu chen Yi-Xin chen School of Chemistry and Chemical Engineering Guangzhou University

A newly developed class of quinoline-based chiral biphosphine ligand, 6,6’-bis（diphenylphosphino）-5,5’- biquinoline（BIQAP） was synthesized via a simple two-step reactions using optically pure BIQOL as starting material and the stereochemical structure of（R）-BIQAP was determined by X-ray crystallography. The chiral BIQAP ligand was successfully applied in Pd-catalyzed asymmetric allylic alkylation of indoles and afforded the desired product in good yields and high enantioselectivities（up to 96% ee）.

关键词： chiral biphosphine ligands palladium asymmetric allylic allylation

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Synthesis of novel chiral biquinolyl biphosphine ligand and ...

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

手性中国2014学术研讨会

作者： Bin Xie Rui Zhang Jin-ping Lu guo-shu chen Yi-Xin chen School of Chemistry and Chemical Engineering Guangzhou University

A novel chiral biphosphine ligands,6,6’-bis（diphenylphosphmo）-5,5’-biquinoline（BIQAP）was synthesized by two step reactions used optical pure BIQOL as starting material and the molecular structure of（R）-BIQAP has been determined by single-crystal X-ray diffractioa The ligand was utilized in Pd-catalysed asymmetric allylic *** enantioselectivety was obtained in C-C and C-N bond formation of l,3-diphenyl-2-propenyl acetate,with dimethyl malonate（up to 94.2%ee）and with aminations（up to 97.8%ee）.

关键词：

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li Yangfei chen Yang Jiang Xiaofei guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

手性Bronsted酸催化炔酰胺不对称去芳构化反应新突破

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科学通报 2021年第35期66卷 4494-4496页

作者：古满珍陈国术刘运林广州大学化学化工学院广州510006

作为一种重要的催化策略,手性Bronsted酸催化在不对称合成中占据着重要地位[1,2].近十几年来该领域的研究取得了很大的进展,但仍局限于通过Bronsted酸活化亚胺和羰基化合物来发展不对称催化反应,而利用手性Bronsted酸直接活化炔烃的不... 详细信息

作为一种重要的催化策略,手性Bronsted酸催化在不对称合成中占据着重要地位[1,2].近十几年来该领域的研究取得了很大的进展,但仍局限于通过Bronsted酸活化亚胺和羰基化合物来发展不对称催化反应,而利用手性Bronsted酸直接活化炔烃的不对称转化一直是该领域的科学难题,迄今为止尚无文献报道.

关键词： Bronsted酸不对称催化反应不对称合成羰基化合物芳构化反应炔烃文献报道不对称转化

借助录像分析技术评估教师专业发展效果——以概念转变教学专业发展为例

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教师教育研究 2023年第3期35卷 91-98页

作者：李诺郭舒晨刘恩山北京师范大学生命科学学院北京100875 南京师范大学教师教育学院江苏南京210023

教育信息化推动了课堂教学的革新,也对教育研究分析工作提出了更高的要求。录像分析技术作为课堂教学研究中的新兴手段,在评估教师参与专业发展培训后的课堂教学效果上具有重要价值。为了解该技术在实践中的应用情况,研究基于一次概念... 详细信息

教育信息化推动了课堂教学的革新,也对教育研究分析工作提出了更高的要求。录像分析技术作为课堂教学研究中的新兴手段,在评估教师参与专业发展培训后的课堂教学效果上具有重要价值。为了解该技术在实践中的应用情况,研究基于一次概念转变教学主题的教师专业发展项目,构建录像分析编码表,对教师参与培训前后的课堂教学录像进行了纵向及横向双重编码分析。结果显示,借助录像分析手段能够明确教师在培训后的课堂实践行为发生的真实改变,且这种改变具有个体差异性,不同的教学策略呈现一定的变化规律。该研究结果将为未来录像分析技术在教师专业发展研究中的实践应用提供借鉴。

关键词：录像分析课堂教学教师专业发展概念转变教学

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

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Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： Xihang chen Zhifeng chen Menghua Li Weiwei guo shuolong Yuan Liangwei Xu Chang Lin Xi Shi Wei chen Shiming Yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine