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Chinese Journal of Chemistry 2016年第5期34卷 490-494页

作者： Taotao Li Peng Yu jin-shun lin Yonggang Zhi Xin-Yuan Liu Chengdu Institute of Organic Chemistry Chinese Academy ofSeienees Chengdu Sichuan 610041 China Department of Chemistry South University of Science and Technology of China Shenzhen Guang dong 518055 China

A Cu-catalyzed remote sp3 C--H/unactivated alkenes functionalization reaction for the concomitant construc- tion of C--CF3 and C--O bonds was described. An 1,5-H radical transfer involving an sp3 C--H bond adjacent to a nitrogen atom and an a-CF3-alkyl radical intermediate derived from unactivated alkenes was observed and demon- strated to proceed via the radical process.

关键词： alkenes radical trifluoromethylation 1,5-H radical transfer Togni's reagent

Chiral N-triflylphosphoramide-catalyzed asymmetric hydroamination of unactivated alkenes: a hetero-ene reaction mechanism

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Organic Chemistry Frontiers 2022年第6期9卷 1649-1661页

作者： Na Wang Li-Wen Fan jin Zhang Qiang-Shuai Gu jin-shun lin Guo-Qiang Chen Xin-Yuan Liu Peiyuan Yu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518071China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China Academy for Advanced Interdisciplinary Studies and Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

A highly enantioselective intramolecular hydroamination reaction catalyzed by chiralN-triflylphosphoramide (NTPA) that features an exceptionally broad substrate scope of isolated unactivated alkenes was recently reported by some of us. Herein we report a detailed density functional theory(DFT) study that unveil an uncommon hetero-ene reaction mechanism for this transformation. The reaction changes from a stepwise mechanism involving discrete tertiary carbocation formation to a concertedmechanism to avoid the generation of energetically unfavorable secondary carbocation species for distinctly substituted alkene substrates. The reactivity of this reaction is primarily affected by the substituentson the internal carbon of the alkene, with the carbocation-stabilizing ones promoting the reaction. Inaddition, the reaction is also influenced by the substituents on the terminal alkene carbons: those diminishing the innate alkene polarization of the starting alkenes retard the reaction by disfavoring the formation of related transition states featuring highly polarized alkene residues. The steric effect of all thesealkene substituents was found to be largely unimportant due to the unique arrangement of the heteroene reaction complex that keeps the reacting alkene away from the sterically congested core region ofthe catalyst pocket. The lower acidity of chiral phosphoric acids than that of chiral NTPAs renders the protonated precomplex along the hetero-ene reaction pathway greatly thermodynamically disfavored. Thisindirectly results in a greater relative distortion in the corresponding transition state, which in turn causesreaction retardation. Our results demonstrate the use of intramolecular pericyclic reactions as an alternative strategy for alkene activation by chiral Brønsted acid catalysis and provide insights into the furtherdevelopment of asymmetric hydrofunctionalization of unactivated alkenes.

关键词： mechanism substituent asymmetric

Radical trifluoromethylation-triggered unactivated alkene and remote C-H bond functionalization

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Radical trifluoromethylation-triggered unactivated alkene an...

基于GPRS网络的环境自动监控数据传输系统的设计

中国化学会全国第十一届有机合成化学学术研讨会

作者： Peng Yu jin-shun lin Lei Li 谭斌刘心元南方科技大学

Enantiopure trifluoromethyl(CF)-containing molecules have been widely applied in syntheses of a large number of ***,the development of versatile,catalytic and enantioselective methodologies through the concurrent activation of simple alkene and C-H bond for the synthesis of enantiopure CF-containing compounds remains a significant *** address this demand and as part of our continued interest in the area of trifluoromethylation and asymmetric catalysis, we herein report a Cu-catalysed unactivated alkene/remote C-H bond difunctionalization reaction for the concomitant construction of C-CF and C-0 bonds towards N.O-aminals with high ***,an asymmetric version of this reaction was also realized by using a Cu/Bronsted acid cooperative catalytic system,providing facile access to valuable chiral CF-containing N,O-aminals with excellent enantioselectivity.

关键词： Trifluoromethylation C-H functionalization Cooperative catalysis Enantioselective N,O-aminals

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江苏环境科技 2004年第3期17卷 11-12页

作者：王经顺张璘江苏省环境监测中心江苏南京210036

分析了江苏省环境自动监控系统数据传输的现状,提出了一种基于GPRS网络的环境自动监控数据传输系统,并进行了详细的设计。

关键词： GPRS网络环境监测系统自动监控数据传输系统中心监控层

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模糊控制在家电产品中的应用与展望

五邑大学学报（自然科学版） 2001年第2期15卷 18-23页

作者：肖健华经顺林五邑大学智能技术与系统研究所广东江门529020 金羚企业集团公司广东江门529040

介绍了模糊控制技术在全自动洗衣机、空调、冰箱等家用电器中的应用，并结合最新的技术手段，讨论了智能家电的发展趋势.

关键词：模糊控制单片机神经网络家用电器智能家电

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Buckling response of offshore pipelines under combined tension, bending, and external pressure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第8期12卷 627-636页

作者： shun-feng GONG lin YUAN Wei-liang jin Institute of Structural Engineering Zhejiang University Hangzhou 310058 China

The buckle and collapse of offshore pipeline subjected to combined actions of tension, bending, and external pressure during deepwater installation has drawn a great deal of attention. Extended from the model initially proposed by Kyriakides and his co-workers, a 2D theoretical model which can successfully account for the case of simultaneous tension, bending, and external pressure is further developed. To confirm the accuracy of this theoretical method, numerical simulations are conducted using a 3D finite element model within the framework of ABAQUS. Excellent agreement between the results validates the effectiveness of this theoretical method. The model is then used to study the effects of several important factors such as load path, material prop-erties, and diameter-to-thickness ratio, etc., on buckling behaviors of the pipes. Based upon parametric studies, a few significant conclusions are drawn, which aims to provide the design guidelines for deepwater pipeline with solid theoretical basis.

关键词： Deepwater Offshore pipeline Buckle External pressure

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Predictive value of a constructed artificial neural network model for microvascular invasion in hepatocellular carcinoma:A retrospective study

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 88-100页

作者： Hai-Yang Nong Yong-Yi Cen Shan-jin Lu Rui-Sui Huang Qiong Chen Li-Feng Huang Jian-Ning Huang Xue Wei Man-Rong Liu lin Li Ke Ding Department of Radiology The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina Department of Radiology Affiliated Hospital of Youjiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Guangxi Clinical Medical Research Center for Hepatobiliary Diseases Affiliated Hospital of Youiiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Department of Ultrasound The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina Department of Hepatobiliary Surgery The Third Affiliated Hospital of Guangxi Medical UniversityNanning 530031Guangxi Zhuang Autonomous RegionChina

BACKGROUND Microvascular invasion(MVI)is a significant risk factor for recurrence and metastasis following hepatocellular carcinoma(HCC)***,there is a paucity of preoperative evaluation approaches for *** To investigate the predictive value of texture features and radiological signs based on multiparametric magnetic resonance imaging in the non-invasive preoperative prediction of MVI in *** Clinical data from 97 HCC patients were retrospectively collected from January 2019 to July 2022 at our *** were classified into two groups:MVI-positive(n=57)and MVI-negative(n=40),based on postoperative pathological *** correlation between relevant radiological signs and MVI status was ***4.6 software and the mutual information method were employed to identify the top 10 dominant texture features,which were combined with radiological signs to construct artificial neural network(ANN)models for MVI *** predictive performance of the ANN models was evaluated using area under the curve,sensitivity,and *** models with relatively high predictive performance were screened using the DeLong test,and the regression model of multilayer feedforward ANN with backpropagation and error backpropagation learning method was used to evaluate the models’*** The absence of a pseudocapsule,an incomplete pseudocapsule,and the presence of tumor blood vessels were identified as independent predictors of HCC *** ANN model constructed using the dominant features of the combined group(pseudocapsule status+tumor blood vessels+arterial phase+venous phase)demonstrated the best predictive performance for MVI status and was found to be automated,highly operable,and very *** The ANN model constructed using the dominant features of the combined group can be recommended as a noninvasive method for preoperative prediction of HCC MVI status.

关键词： Hepatocellular carcinoma Texture analysis Magnetic resonance imaging Microvascular invasion Pseudocapsule Tumor blood vessels

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World Journal of Clinical Cases 2025年第6期13卷 24-29页

作者： Wen-jin Yuan Yi-Juan Zheng Bing-Rong Zhang Yi-Jie lin You Li Yan-Yan Qiu Xue-Ping Yu Department of Infection Disease Clinical Medical Research Center for Bacterial and Fungal Infectious Diseases of Fujian provinceFujian Medical University Affiliated First Quanzhou HospitalQuanzhou 362000Fujian ProvinceChina

BACKGROUND Hydroxyurea,an antimetabolite,is frequently prescribed for various hemato-logical disorders,and its common side effects include gastrointestinal problems,cutaneous or mucosal lesions and pyrexia/*** SUMMARY This study reports the case of a 67-year-old woman who developed recurrent abdominal pain after 10 years of continuous hydroxyurea therapy for primary *** revealed an ileocecal *** discontinuing hydroxyurea therapy for 6 months,follow-up colonoscopy showed a significant reduction in the *** We consider cecal ulcers as a rare complication of hydroxyurea therapy which typically resolves upon stopping the drug.

关键词： Hydroxyurea Ulcer Abdominal pain Thrombocythemia Colonoscopy Case report

基于REOF的不同量级降雨侵蚀力时空变化——以重庆市为例

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西南大学学报（自然科学版） 2025年第1期47卷 163-177页

作者：靳军英王林金铁生张卫华西南大学资源环境学院重庆400715

研究重庆市不同地理分区内各量级降雨侵蚀力的时空变化特征,为该地区进行更加精准的区域性水土流失防治工作提供理论依据。选取1981-2020年重庆市31个站点逐日降雨数据,利用旋转经验正交函数(Rotated Empirical Orthogonal Function,RE... 详细信息

研究重庆市不同地理分区内各量级降雨侵蚀力的时空变化特征,为该地区进行更加精准的区域性水土流失防治工作提供理论依据。选取1981-2020年重庆市31个站点逐日降雨数据,利用旋转经验正交函数(Rotated Empirical Orthogonal Function,REOF)对降雨侵蚀力进行地理分区,并结合R/S、5年滑动平均、Mann-Kendall检验等方法,分析各分区不同量级降雨侵蚀力时空变化。结果表明:①重庆市降雨侵蚀力可分为6个地理区域(Ⅰ-Ⅵ区);②重庆市多年平均降雨侵蚀力为5784.04 MJ·mm/(hm^(2)·h·a),不同降雨侵蚀力从大到小依次为:大雨、暴雨、中雨、大暴雨;③大雨侵蚀力在Ⅰ-Ⅲ区和Ⅴ-Ⅵ区占主导优势,暴雨侵蚀力在Ⅳ区占主导优势。各分区中,中雨、大雨及暴雨侵蚀力主要集中在5-9月,大暴雨侵蚀力集中在6-8月;④各区不同量级降雨侵蚀力年际变化从小到大依次为:中雨、大雨、暴雨、大暴雨;同一量级降雨侵蚀力的整体变化趋势均不显著;Hurst指数表明,中雨侵蚀力在Ⅰ和Ⅴ区、大雨侵蚀力在Ⅱ和Ⅴ区、大暴雨侵蚀力在Ⅰ和Ⅲ区呈强持续上升趋势;⑤中雨、大雨及大暴雨侵蚀力在渝东南、渝东北占主导优势,暴雨侵蚀力在渝西以及重庆中部占主导优势,且Ⅰ区酉阳和秀山、Ⅱ区开州、Ⅲ区北碚和铜梁、Ⅳ区璧山和永川、Ⅴ区巫溪和云阳及Ⅵ区忠县是不同量级降雨侵蚀力的高峰中心。通过对重庆各分区不同量级降雨侵蚀力的分析,明确了可能引起土壤侵蚀的主要雨型、高发时期和潜在风险较高的地区,可为区域水土流失动态监测和水土保持措施的合理制定提供参考。

关键词：降雨侵蚀力时空变化旋转经验正交分解法 MK非参数趋势检验 R/S分析法

Strain in perovskite solar cells: origins, impacts and regulation

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National Science Review 2021年第8期8卷 39-56页

作者： jinpeng Wu shun-Chang Liu Zongbao Li Shuo Wang Ding-Jiang Xue Yuan lin jin-Song Hu Beijing National Laboratory for Molecular Sciences(BNLMS) Institute of ChemistryChinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences School of Material and Chemical Engineering Tongren University

Metal halide perovskite solar cells(PSCs) have seen an extremely rapid rise in power conversion efficiencies in the past few years. However, the commercialization of this class of emerging materials still faces serious challenges, one of which is the instability against external stimuli such as moisture, heat and *** focus has deservedly been placed on understanding the different origins of intrinsic instability and thereby enhancing their stability. Among these, tensile strain in perovskite films is an important source of instability that cannot be overcome using conventionally extrinsic stabilization approaches such as encapsulation. Here we review recent progress in the understanding of the origin of strain in perovskites as well as its corresponding characterization methods, and their impacts on the physical properties of perovskites and the performance of PSCs including efficiency and stability. We then summarize the latest advances in strain-regulation strategies that improve the intrinsic stability of perovskites and photovoltaic devices. Finally, we provide a perspective on how to make further progress in stable and high-efficiency PSCs via strain engineering.

关键词： perovskite stress strain stability solar cells