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NHC-mediated photocatalytic para-selective C–H acylation of aryl alcohols: regioselectivity control via remote radical spiro cyclization

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Science China Chemistry 2025年

作者： tinglei Zhang Lala Wang Xiaolin Peng Tianhui Liao Dongmei Chen ting tu Donghan Liu Ziye Cheng Shiqing Huang Shi-Chao Ren Xinglong Zhang Yonggui Robin Chi State Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Qiannan Medical College for Nationalities School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Department of Chemistry The Chinese University of Hong Kong Institute of High Performance Computing Agency for Science Technology and Research

Friedel-Crafts reaction and transition-metal catalysis represent primary methodologies for arene acylation; however, suffer from certain limitations, such as electronic effect-dependent reactivity, regioselectivity issues, the necessity of directing group, and relatively exceptionally limited exploration in meta-and para-acylations. N-heterocyclic carbene(NHC) catalysis has recently emerged as a promising alternative strategy for arene acylation, offering distinct regioselectivity profiles that are challenging to achieve through known methods. Herein, an NHC-mediated photo-catalytic para-selective C–H acylation of aryl alcohols is disclosed. The reaction employs a remote radical-induced temporary spiro cyclization strategy, proceeding via tandem radical dearomatization, radical acylation, rearomatization processes. Combined experimental and computational mechanistic studies support the proposed reaction pathway and observe an exclusive para-selectivity regardless of the nature of the substituents on the substrates. Despite the less satisfactory yields, the current method exhibits non-electronic nature-based reactivity and regioselectivity, enabling quick access to acylated arenes that are difficult or impossible for reported methods.

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Effect of final electromagnetic stirring on solidification microstructure of GCr15 bearing steel in simulated continuous casting

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Journal of Iron and Steel Research International 2020年第2期27卷 141-147页

作者： Dan-qing Jiang Rui Wang Qiong Zhang Zhen-qiang Zhang ting-sheng tu Jiang Wang Zhong-ming Ren School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The effect of final electromagnetic stirring on the solidification structure,element segregation,and carbides of GCrl5 bearing steel was *** experiment of continuous casting of the steel was carried out by using a continuous casting physical simulation apparatus with the final electromagnetic *** liquid core profile was revealed by the pour-out method during the solidification *** ingots were produced under different electromagnetic stirring parameters for *** results show that,at the final stage of solidification,intense electromagnetic stirring exacerbates the central carbon segregation,resulting in more serious precipitation of the primary *** is also found that the carbides in the segregation area are dominantly M3C type,together with a small amount of M7C3-type and M3C2-type *** this physical simulation model,the optimal stirring parameters to obtain a fine and homogeneous structure are the liquid pool width of 15 mm,current intensity of 150 A,and stirring frequency of 5 Hz.

关键词： GCrl5 bearing steel Solidification structure Continuous casting Final electromagnetic stirring Segregation Carbide

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Synthesis of cerium oxalate hydrate by precipitation technique under external magnetic field

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Rare Metals 2023年第3期42卷 1028-1035页

作者： Jian-Bo Yu Zhi-Gang Yang Zhi-Hao Wang ting-Sheng tu Zhen-Qiang Zhang Jing-Yun Li Yun-Bo Zhong Zhong-Ming Ren State Key Laboratory of Advanced Special Steels School of Material Science and EngineeringShanghai UniversityShanghai 200072China School of Material Science and Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Cerium oxalate hydrate particles were synthesized by precipitation technique under external magnetic field with respective intensities of 0,0.1,0.3,and 0.6 *** particle morphologies were investigated by scanning electron microscopy(SEM)and transmission electron microscope(TEM).Results show that external magnetic field has a great influence on the growth behavior of cerium oxalate hydrate ***-like and plate-like cerium oxalate hydrate particles with smaller size are formed without the applying of external magnetic ***,the extremely big rod-like particles with the average size of 12.47μm were prepared under external magnetic field of 0.6 *** increasing magnetic field intensity makes the grain grow *** analysis supports the presence of 8.5 H_(2)O molecules associated with cerium ***,the growth mechanism of cerium oxalate hydrate under external magnetic field was briefly discussed.

关键词： Cerium oxalate hydrate Precipitation technique Magnetic field Grain Growth

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In vitro inhibition of HIV-1 replication in autologous CD4*T cells indicates viral containment by multifactorial mechanisms

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Virologica Sinica 2017年第6期32卷 485-494页

作者： ting tu Jianbo Zhan Danlei Mou Wei Li Bin Su Tong Zhang Tao Li Ning Li Hao Wu Cong Jin Huabiao Chen Jiangsu Key Laboratory of Clinical Laboratory Medicine Jiangsu University School of MedicineZhenjiang 212013China National HIV/HCV Reference Laboratory National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Hubei Provincial Center for Disease Control and Prevention Wuhan 430079China Beijing You'an Hospital Capital Medical UniversityBeijing 100069China

HIV-1-specific cytotoxic T lymphocytes(CTLs) and neutralizing antibodies(NAbs) are present during chronic infection, but the relative contributions of these effector mechanisms to viral containment remain unclear. Here, using an in vitro model involving autologous CD4+ T cells,primary HIV-1 isolates, HIV-1-specific CTLs, and neutralizing monoclonal antibodies, we show that b12, a potent and broadly neutralizing monoclonal antibody to HIV-1, was able to block viral infection when preincubated with virus prior to infection, but was much less effective than CTLs at limiting virus replication when added to infected cell cultures. However, the same neutralizing antibody was able to contain viruses by antibody-dependent cell-mediated virus inhibition in vitro,which was mediated by natural killer cells(NKs) and dependent on an Fc-Fc receptor ***, bulk CTLs from HIV-1 controllers were more effective in suppression of virus replication than those from progressors. These findings indicate that control of HIV-1 replication in activated CD4^+ T cells is ineffectively mediated by neutralizing antibodies alone, but that both CTLs and antibody-dependent NK-mediated immune mechanisms contribute to viral containment. Our study systemically compared three major players in controlling HIV-1 infection, CTLs, NAbs, and NKs, in an autologous system and highlighted the multifactorial mechanisms for viral containment and vaccine success.

关键词： HIV-1 infection viral replication cytotoxic T lymphocyte(CTL) natural killer cells neutralizing antibody

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新型密封偏心自适应调节方法与减振实验研究

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振动与冲击 2017年第19期36卷 52-59页

作者：李宽何立东涂霆北京化工大学化工安全教育部工程研究中心北京100029

针对转子偏心引起的密封流体激振问题,设计了一种新型偏心自适应调节密封结构。该结构可自适应地减小转子偏心量,抑制密封流体激振。对其抑振机理进行探究,得出当偏心自调结构的固有频率和转子密封系统的激励频率一致时,其抑振效果最好... 详细信息

针对转子偏心引起的密封流体激振问题,设计了一种新型偏心自适应调节密封结构。该结构可自适应地减小转子偏心量,抑制密封流体激振。对其抑振机理进行探究,得出当偏心自调结构的固有频率和转子密封系统的激励频率一致时,其抑振效果最好;随着两者差值增大,其抑振效果变弱。以水作为密封介质,测量了不同弹簧刚度下偏心自调结构的固有频率,并改变转子转频,对其抑振规律进行实验研究。结果表明该结构固有频率随弹簧刚度增大而增大,但与激励频率差别较大,振动降幅只在10%~20%。将偏心自调结构浸于水,测量其固有频率,对其抑振规律进行实验研究。结果表明浸在水中时该结构固有频率值依然随弹簧刚度增大而增大,但比在空气中时减小了约40%,更加接近激励频率,抑制效果显著,振动降幅最大可达41.27%。

关键词：非接触密封密封流体激振偏心自适应调节固有频率

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Prevalence of acne in Chinese college students and its associations with social determinants and quality of life:a population-based cross-sectional study

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Chinese Medical Journal 2021年第10期134卷 1239-1241页

作者： Li Zhu Min-Xue Shen Elham Samran Ya-ting tu Xiang Chen Juan Tao Yan Li Shiyan Renmin Hospital Hubei University of MedicineShiyanHubei 442000China Department of Dermatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China Department of Dermatology Xiangya HospitalCentral South UniversityChangshaHunan 410008China

To the Editor:Acne vulgaris is a common chronic inflammatory skin *** is the 8th most prevalent disease in the *** adolescents,more than 85%once suffered from acne.[1]Moreover,according to the recent evidence,[2]patients often experience great physical and mental stress especially among the college students,due to its recurrence and scars or post-inflammatory hyperpigmentation left after *** China,while there are many studies on acne among adolecents and young adults,most of them are *** selection bias may be introduced in these studies because patients with severer symptoms or signs of disease are more likely to seek medical care,and perceive more impaired quality of *** epidemiologic data from population-based studies in China are still *** study aims to estimate the prevalence of moderate and severe acne in Chinese college students and assess its impact on the quality of life.

关键词： likely college impaired

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美国公共图书馆动漫资源建设和动漫阅读推广服务对我国公共图书馆的启示

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图书馆理论与实践 2017年第12期 84-87页

作者：涂婷婷夏南强华中师范大学信息管理学院

通过对美国公共图书馆动漫资源建设和开展动漫阅读推广服务现状的介绍,论述了其对于我国公共图书馆开展动漫阅读推广活动的启示。提出我国公共图书馆应该重视动漫资源建设,成立专门的动漫阅读推广部门,丰富动漫阅读推广内容,建设动漫阅... 详细信息

通过对美国公共图书馆动漫资源建设和开展动漫阅读推广服务现状的介绍,论述了其对于我国公共图书馆开展动漫阅读推广活动的启示。提出我国公共图书馆应该重视动漫资源建设,成立专门的动漫阅读推广部门,丰富动漫阅读推广内容,建设动漫阅读推广合作机制。

关键词：动漫资源建设动漫阅读推广公共图书馆美国

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基于分块和仿射不变性的SIFT图像匹配算法

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计算机应用研究 2018年第11期35卷 3504-3507页

作者：涂婷陆济湘武汉理工大学理学院武汉430070

针对传统SIFT算法在匹配时出现实时性差、匹配量低以及RANSANC算法在剔除SIFT误匹配对时误匹配率高的问题,提出一种基于距离相对性的分块匹配算法和基于仿射不变性的误匹配对剔除算法。首先利用传统SIFT算法提取图像中的特征点;然后采... 详细信息

针对传统SIFT算法在匹配时出现实时性差、匹配量低以及RANSANC算法在剔除SIFT误匹配对时误匹配率高的问题,提出一种基于距离相对性的分块匹配算法和基于仿射不变性的误匹配对剔除算法。首先利用传统SIFT算法提取图像中的特征点;然后采用基于距离相对性的分块匹配算法进行特征匹配得到初始匹配对;由于初始匹配对中存在误匹配,运用基于仿射不变性的误匹配对剔除算法来剔除误匹配对;最后,在不同图像变换下进行仿真实验。实验结果表明,算法在保持SIFT算法鲁棒性的基础上能够得到更多匹配对,正确匹配率提高了10%左右,并且实时性也得到了很大改善。

关键词： SIFT 特征匹配分块仿射不变性

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Improvement of the Yield Function of Continuum Mechanics of Textured Polycrystals

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Advances in Manufacturing 2000年第4期4卷 327-331页

作者： Da-wei Lin ting-sheng tu School of Material Science and Engineering Shanghai University Shanghai China

The calculation procedure of the continuum mechanics of textured polycrystals (CMTP) method is reviewed to estimate calculating time with various yield functions (YFs). A so called semi quadratic YF is proposed to eliminate time consuming numerical calculation and avoid the decrease of prediction precision. The reasonability of the new YF is proved by making the comparisons between predicted R values and earing behaviour for some materials and the experimental results.

关键词： CMTP method yield function plastic anisotr\

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大棚韭菜高效栽培技术

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东南园艺 2016年第3期4卷 35-37页

作者：涂婷福建省大田县农业局福建大田366100

近年来,大棚韭菜发展迅速,本文对大棚韭菜的品种选择、播种期、苗期管理、定植及当年田间管理、定植后一年以上田间管理进行了实践总结,为大力推广大棚韭菜种植提供技术参考。

关键词：大棚韭菜栽培技术

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