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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-Zhao xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Therapeutic effect and mechanism of breviscapine on cisplatin-induced nephrotoxicity in mice

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Asian Pacific Journal of Tropical Medicine 2015年第10期8卷 853-857页

作者： xiao-Yu lou Jing-liang Cheng Bo Zhang Department of Magnetic Resonance Imaging the First Affiliated Hospital of Zhengzhou University Department of Magnetic Resonance Imaging the First Affiliated Hospital of Luohe Medical College Department of Ultrasound in Medicine East HospitalTongji University School of Medicine

Objective:To observe the protective effect of breviscapineon mice with cisplatin-induced ***:Mice were given a single injection of cisplalin(8 mg/kg,up.);then,breviscapine was given to mice at 25 mg/kg and 50 mg/kg doses,respectively,once a day for seven *** tissue structure was observed after animals were *** urea nitrogen(BUN),serum creatinine(Scr),lipid peroxide(MDA) and superoxide dismutase(SOD) serum levels were detected;and MDA,glutathione peroxidase,and SOD levels in the renal cortex were ***:Compared with the blank control group(BCG),the kidney pathological damage of mice in the model control group(MCG) was more *** applying different doses of breviscapine,different degrees of renal injury improvement *** with the BCG,the serum levels of Scr and BUN in the MCG increased to(89.92±6.78) μmoL/L and(15.32±4.53) mmoL/*** differences were statistical significant(P<0.01).Compared with the MCG,the serum levels of Scr and BUN in the Bre low-dose groups and Bre high-dose groups decreased significantly(P<0.05).Compared with the BCG,the MDA levels in serum and in the renal cortex in the MCG significantly increased,while the SOD levels significantly *** the differences were statistically significant(P<0.01).In the Bre low-dose groups and Bre high-dose groups,MDA levels in serum and in the renal cortex significantly decreased,while SOD and glutathione peroxidase levels in the renal cortex significantly increased,compared with the MCG;and the differences were statistically significant(P<0.05).Conclusions:Breviscapine can reduce cisplatin induced renal toxicity in mice and it's possible through inhibition of renal tubule cell lipid peroxidation and reduces the nephrotoxicity of cisplatin.

关键词： Cisplatin Renal injury Breviscapine Protective eff

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Parametric Stability Analysis of Marine Risers with Multiphase Internal Flows Considering Hydrate Phase Transitions

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Journal of Ocean University of China 2021年第1期20卷 23-34页

作者： liang Weixing lou Min College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China

This study investigates the effects of multiphase internal flows that consider hydrate phase transitions on the parametric stability of marine risers.A numerical model of the multiphase internal flow that considers a hydrate phase transition is *** model first solves the flow parameters and subsequently obtains the natural frequencies of risers with different gas intake *** stability charts of marine risers with different gas intake ratios are plotted by applying Floquet theory,and the effects of the gas intake ratio on the instability and vibration response of the risers are *** natural frequency increases with an increase in the gas intake ratio;thus,instability zones move to higher frequency ranges in the stability *** the increasing gas intake ratio reduces the damping effect of the Coriolis force,the critical amplitude of the heave in the unstable region decreases,especially when hydrodynamic damping is not *** a result,higher-order unstable regions are *** in an unstable region,the vibration response curve of a riser with a high gas intake ratio excited by parametric resonance diverges quickly due to parametric resonance.

关键词： hydrate phase transition marine risers multiphase internal flow parametric stability vibration response

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养血清脑颗粒对短暂性脑缺血发作血浆溶血磷脂酸水平影响的观察

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中国实用内科杂志 2009年第4期29卷 367-368页

作者：楼小亮詹细平李晓萍范华谭建萍陈南星周征成李欣弘杨宏武南昌大学第四附属医院神经内科南昌330003

近年来的研究表明,溶血磷脂酸(LPA)是一个致动脉硬化和致血栓形成因子,在短暂性脑缺血发作(TIA)发生中起重要作用。TIA作为完全性卒中的特级预报,临床尽早发现其高危者,并予相应的综合治疗,既可有效的控制TIA的发展,又可合理的利用有限... 详细信息

近年来的研究表明,溶血磷脂酸(LPA)是一个致动脉硬化和致血栓形成因子,在短暂性脑缺血发作(TIA)发生中起重要作用。TIA作为完全性卒中的特级预报,临床尽早发现其高危者,并予相应的综合治疗,既可有效的控制TIA的发展,又可合理的利用有限的医疗资源。本文旨在观察不同危险程度的TIA患者血浆LPA水平及养血清脑颗粒对其影响。[第一段]

关键词：养血清脑颗粒短暂性脑缺血发作溶血磷脂酸 ABCD评分

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血浆溶血磷脂酸水平与急性脑梗死预后的关系

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江西医学院学报 2008年第4期48卷 59-61页

作者：詹细平楼小亮徐江霞龚淑琪李晓萍范华南昌大学第四附属医院神经内科南昌330003 南昌大学第四附属医院检验科南昌330003

目的探讨急性脑梗死患者血浆溶血磷脂酸(lysophosphatidic acid,LPA)水平与预后的关系。方法采用有机溶剂抽提,并进一步分离出溶血磷脂酸,以定磷方法测定62例急性脑梗死(脑梗死组)患者[90 d内死亡者(死亡组)12例,生存者(生存组)50例;根... 详细信息

目的探讨急性脑梗死患者血浆溶血磷脂酸(lysophosphatidic acid,LPA)水平与预后的关系。方法采用有机溶剂抽提,并进一步分离出溶血磷脂酸,以定磷方法测定62例急性脑梗死(脑梗死组)患者[90 d内死亡者(死亡组)12例,生存者(生存组)50例;根据Barthel指数评分,将50例生存者分为3组:轻度功能障碍组17例、中度功能障碍组16例和重度功能障碍组17例]和62例健康体检者(对照组)血浆LPA水平。结果脑梗死组血浆LPA水平显著高于对照组(P<0.01);死亡组血浆LPA水平显著高于生存组(P<0.01),重度功能障碍组血浆LPA水平显著高于中度功能障碍组(P<0.01)、中度功能障碍组高于轻度功能障碍组(P<0.05)。结论血浆LPA水平可作为急性脑梗死诊断和预后评估的一个重要的生物学指标。

关键词：溶血磷脂酸脑梗死,急性预后 Barthel指数

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Experimental Investigation of Multi-Mode Vortex-Induced Vibration of Flexible Risers with Different Mass Ratios

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China Ocean Engineering 2023年第1期37卷 1-15页

作者： WANG Yu lou Min REN xiao-hui liang Wei-xing LI Xiang DANG Peng-bo School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao 266580China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China

Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 1600-14400. The dynamic responses of riser models versus reduced velocity were analyzed, and the spanwise displacement, frequency,and trajectory of the mode conversion from the lower to the higher mode were explored. The results revealed that the riser model with a higher mass ratio excites a higher number of modes. The conversion region of multi-mode competition exists and narrows with the increasing mass ratio. Mode conversion is continuous and manifests as the transmission of peaks and troughs in mode shape: the peaks and troughs of mode shape move up in the mode stable development region and move down in the mode conversion region. The single-mode dominating vibration exhibits a standing wave feature, and the traveling wave feature is significant in the mode conversion region. Furthermore, the frequency jump is always transmitted from the trough to the peak of the mode shape, and finally, all the axial positions vibrate at the same frequency. The trajectory in the mode conversion region deviates from the 8-shape and recovers the standard8-shape at the middle and late stages of the mode stable development region.

关键词： vortex-induced vibration dynamic response mode conversion mass ratio mode weight

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Orbitronics for energy-efficient magnetization switching

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Science China(Information Sciences) 2025年第1期 398-399页

作者： Yuxuan YAO Daoqian ZHU Qingtao XIA Jianing liang Yuhao JIANG Zhiyang PENG Jiaxu LI Chen xiao Renyou XU Wenwen WANG Xiantao SHANG Shiyang LU Dapeng ZHU Hong-Xi LIU Kaihua CAO Weisheng ZHAO Fert Beijing Institute School of Integrated Circuit Science and Engineering Beihang University National Key Lab of Spintronics Institute of International Innovation Beihang University Qingdao Research Institute Beihang University Truth Memory Corporation

Spin-orbit torque （SOT）,as a promising writing method for magnetic random-access memory （MRAM）,has garnered widespread interest for over a decade [1].Heavy metals,such as β-W,have been broadly adopted as spin current sources,but suffer from phase change at a limited thickness,resulting in a dramatic reduction of the charge-tospin conversion efficiency θSH[2].The thickness limitation leads to stringent etching conditions and large distribution among devices,posing challenges for simultaneously satisfying SOT efficiency,etching-stop margins,and back-end-ofline （BEOL） compatibility.

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贸易便利化对中国机电产品出口影响——基于东盟十国的实证分析

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江苏商论 2025年第1期 37-42页

作者：梁晓凯杭州师范大学阿里巴巴商学院浙江杭州311121

随着全球贸易自由化程度的不断加深,贸易便利化水平的提高对于国际贸易流量的影响日益凸显。本研究采用中国对东盟各成员国机电产品出口额面板数据研究贸易使得化问题。结果表明,贸易便利化对扩大中国机电产品出口额具有明显促进作用,... 详细信息

随着全球贸易自由化程度的不断加深,贸易便利化水平的提高对于国际贸易流量的影响日益凸显。本研究采用中国对东盟各成员国机电产品出口额面板数据研究贸易使得化问题。结果表明,贸易便利化对扩大中国机电产品出口额具有明显促进作用,同时国内生产总值、人口总量对该产品出口额也有显著正向效应。由此应进一步提升东盟各国贸易便利化水平,努力扩大中国机电产品出口规模。

关键词：东盟贸易便利化机电产品出口贸易

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A Binary Supramolecular Assembly with Intense Fluorescence Emission, High pH Stability, and Cation Selectivity: Supramolecular Assembly-Induced Emission Materials

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Research 2019年第1期2019卷 772-781页

作者： Xu Wang Xin-Yue lou xiao-Yu Jin Feng liang Ying-Wei Yang State Key Laboratory of Inorganic Synthesis and Preparative Chemistry International Joint Research Laboratory of Nano-Micro Architecture ChemistryCollege of ChemistryJilin University2699 Qianjin StreetChangchun 130012China Te State Key Laboratory of Refractories and Metallurgy School of Chemistry&Chemical EngineeringWuhan University of Science and TechnologyWuhan 430081China

We construct a fuorescent supramolecular system(TPE-Q_(4)⊂DSP5)of excellent tolerance to a wide range of pH by the facile selfassembly of a new pillar[5]arene bearing disulfonated arms(DSP5)with an AIE-active tetraphenylethene-based tetratopic guest bearing four quaternary ammonium binding sites(TPE-Q_(4)),which exhibits strong blue emission even in dilute aqueous solutions along with much higher quantum yield and longer fuorescence lifetime than TPE-Q_(4) *** appreciable property can be attributed to the supramolecular assembly-induced emission(SAIE)mechanism endowed by the host-guest inclusion complexation based on synthetic ***,the enhanced fuorescence of the supramolecular assembly is quenched efciently and exclusively by ferric ions in water with a high Stern–Volmer formula constant of 1.3×10^(5) mol^(−1),demonstrating the excellent cation selectivity and visualized responsiveness in ion sensing and detection.

关键词： dilute Fluorescence attributed

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Formula of Overtopping Discharge of Vertical Seawall with A Form Similar to Solitary Wave Function

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China Ocean Engineering 2022年第5期36卷 802-807页

作者： LI xiao-liang School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

An empirical formula to predict overtopping discharge of vertical wall is presented,in which an expression similar to the solitary wave function is proposed to describe the rule of the influence of relative water *** formula is derived from performing an investigation to the well-known overtopping graphs of Goda,and for the sake of interest,the process of the derivation is *** make clear the formula’s performance,relevant test datasets in the CLASH database are extracted to examine the error levels of the *** a result,an overall good agreement has been found between the predictions of the formula and the extracted datasets in a wide range outside the extreme shallow region,i.e.,the range of relative water depth smaller than 0.6,in which the water depth near the wall is so shallow that nearly all the incoming waves have been broken before reaching the wall.

关键词： overtopping discharge formula vertical wall Goda graph

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