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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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Determination of sulfite in water samples by flow injection analysis with fluorescence detection

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Chinese Chemical Letters 2010年第12期21卷 1457-1461页

作者： Li qian yin Dong xing Yuan Min Zhang State Key Laboratory of Marine Environmental Science Environmental Science Research Centre Xiamen University Xiamen 361005 China

A fast,sensitive,and reliable method for the determination of sulfite（SO3^2-） in fresh water and seawater samples was *** proposed method was based on the reaction of o-phthalaldehyde（OPA）-sulfite-NH_3 in alkaline solution,with flow injection analysis and fluorescence *** experimental parameters were investigated in pure water and seawater matrixes. The detection limits（S/N = 3） were 0.006μmol/L in pure water and 0.018μmol/L in seawater for SO3^2-.The method was successfully applied to analyze SO3^2- iin the samples of rain water and flue gas desulfurization seawater.

关键词： Sulfite Fluorophotometry FIA Flue gas desulfurization seawater Rainwater

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间歇与持续训练对体力活动不足成人生活质量影响的Meta分析

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中国组织工程研究 2025年第8期29卷 1727-1740页

作者：郑华坤殷明越刘骞四川农业大学体育学院四川省雅安市625014 上海体育大学竞技运动学院上海市200438

目的:高强度间歇训练(high-intensity interval training,HIIT)和中等强度持续训练(moderate-intensity continuous training,MICT)对临床慢性病患者生活质量均有改善作用,但其对于体力活动不足成人的应用效果与调节因素尚不明确。文章... 详细信息

目的:高强度间歇训练(high-intensity interval training,HIIT)和中等强度持续训练(moderate-intensity continuous training,MICT)对临床慢性病患者生活质量均有改善作用,但其对于体力活动不足成人的应用效果与调节因素尚不明确。文章旨在探究HIIT与MICT对体力活动不足成人生活质量的应用效果与调节因素。方法:在Web of Science核心合集、Medline(EBSCO Host)、PubMed和Cochrane Library数据库中进行文献检索,检索时限为各数据库建库至2023年9月。纳入文献类型为随机对照试验,研究对象为体力活动不足成人。采用RevMan 5.4软件和GRADE证据评价框架对纳入文献进行质量评价。使用R Studio(版本4.2.0)进行随机效应模型的主效应合并。亚组分析、回归分析和敏感性分析用于探讨研究异质性来源和调节因素。结果:①纳入32项中等至高质量的随机对照试验,共2083名体力活动不足成人对象(HIIT组474例;MICT组708例;对照组901例)。②相比于无训练对照组,HIIT(Hedges’g=0.61;95%CI:0.40-0.83;I2=45%)与MICT(Hedges’g=0.66;95%CI:0.25-1.08;I2=89%)均能显著提升生活质量。当直接比较HIIT与MICT时,二者之间的影响未观察到显著差异(Hedges’g=-0.01;95%CI:-0.23-0.21;I2=0%)。③亚组分析结果显示,HIIT和MICT在提高身体层面的生活质量更为有效(HIIT:Hedges’g=0.82 vs.0.75;MICT:Hedges’g=0.74 vs.0.55),而骑行在提高整体生活质量方面有更好的趋势(HIIT:Hedges’g=0.74 vs.0.36;MICT:Hedges’g=1.08 vs.0.52)。④回归分析未识别出任何显著的调节因素(所有因素P>0.05)。⑤上述Meta分析均未发现发表偏倚(Egger检验P>0.05)。结论:①中高级别的证据表明,HIIT与MICT均能改善体力活动不足成人的生活质量,且二者之间的干预效果类似。因此,在选择这两种方案时,需综合考虑安排灵活性、时间经济性以及应用可行性等因素制订个性化运动方案。②文章推荐在应用HIIT时,3次/周,使用低量方案(例如,每次5组,每组1 min),以80%-95%最大心率进行骑行可达理论最佳改善效果。③尽管MICT可提高生活质量,但尚无充分证据显示增加运动时长会带来额外益处。因此,建议在实施MICT时,每周进行3次以上,每次训练时长控制在25-60 min,并以50%-75%最大心率进行骑行,以达到理论上预期的最佳改善效果。

关键词：运动干预高强度间歇训练中等强度持续训练生活质量 Meta分析体力活动不足身心健康随机对照试验

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日本数字疗法管理及医保支付的经验与启示

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卫生软科学 2025年第1期39卷 90-94页

作者：邢倩何达上海市卫生和健康发展研究中心/上海市医学科学技术情报研究所上海201199

通过梳理日本数字疗法的应用现状、医保支付路径及标准,发现日本数字疗法的准入在传统医疗器械框架下进行,得益于独立的分类管理和监管策略,以及产学研数据共享和数字疗法的快速发展。但较为有限的卫生技术评估基础导致数字疗法评估维... 详细信息

通过梳理日本数字疗法的应用现状、医保支付路径及标准,发现日本数字疗法的准入在传统医疗器械框架下进行,得益于独立的分类管理和监管策略,以及产学研数据共享和数字疗法的快速发展。但较为有限的卫生技术评估基础导致数字疗法评估维度不全面,伦理审查和社会影响有潜在隐患。基于此提出未来我国可探索以真实世界证据为准绳,尝试快速审查与支付的地区试点,确保多方利益和伦理考量,定期进行影响评估以保障数字疗法健康发展。

关键词：数字疗法政策保障医疗保险日本

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Analytical solution for the effective elastic properties of rocks with the tilted penny-shaped cracks in the transversely isotropic background

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Petroleum Science 2024年第1期21卷 221-243页

作者： Zheng-qian Ma xing-Yao yin Zhao-Yun Zong Yuan-Yuan Tan Ya-Ming Yang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266200ShandongChina

Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is ***,up to now,multitudinous analytical models focus primarily on the cracked rock with the isotropic background,while the explicit model for the cracked rock with the anisotropic background is rarely investigated in spite of such case being often encountered in the ***,we first studied dependences of the crack opening displacement tensors on the crack dip angle in the coordinate systems formed by symmetry planes of the crack and the background anisotropy,respectively,by forty groups of numerical *** on the conclusion from the experiments,the analytical solution was derived for the effective elastic properties of the rock with the inclined penny-shaped cracks in the transversely isotropic ***,we comprehensively analyzed,according to the developed model,effects of the crack dip angle,background anisotropy,filling fluid and crack density on the effective elastic properties of the cracked *** analysis results indicate that the dip angle and background anisotropy can significantly either enhance or weaken the anisotropy degrees of the P-and SH-wave velocities,whereas they have relatively small effects on the SV-wave velocity ***,the filling fluid can increase the stiffness coefficients related to the compressional modulus by reducing crack compliance parameters,while its effects on shear coefficients depend on the crack dip *** increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip *** comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness ***,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the or

关键词： Effective elastic property Tilted crack Transverse isotropy Analytical solution Crack opening displacement

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The spatial distribution characteristics of shallow fissures of a landslide in the Wenchuan earthquake area

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Journal of Mountain Science 2016年第9期13卷 1544-1557页

作者： XU xing-qian Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Shallow fissures, being the main infiltration paths of fluid on the surface of a slope, played an important role in the whole process of a landslide. However, the spatial distribution characteristics of fissures in the slope are difficult to be determined. In this study, we attempted to characterize the variation pattern of slope fissures along depth in the Wenchuan earthquake area in Sichuan Province by combining engineering geological investigation, geomorphologic analysis and geophysical investigation. The geophysical methods that were used in this study include Multichannel Analysis of Surface Wave(MASW), Ground Penetrating Radar(GPR) and Electrical Resistivity Tomography(ERT). The results suggested that geophysical parameters(shear wave velocity, electromagnetic signals attenuation and resistivity) could provide valuable information for the spatial network of shallow fissures. Through the verification by engineering geological survey and geophysical sensitivity analysis, this work highlighted that MASW was the most appropriate technique to delineate the propagation of shallow fissures in a gravel soil slope.

关键词： Shallow fissures Landslide Wenchuanearthquake Geophysical prospecting

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The study of human health effect induced by depth information of stereo vision film

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Journal of Innovative Optical Health Sciences 2015年第5期8卷 31-39页

作者： Xiao Wang Zhiyu qian Lidong xing Shuai Jin Baoyu Liu Zhongqiang Li Jianhua yin Nanjing University of Aeronautics and Astronautics Nanjing P.R.China

The stereo vision results from the interaction between geometrical optics and visual *** depth will bring discomforts for the results of ghosting and *** relevance of the ratio of jumping out depth(RJD)and electroencephalogram(EEG)gravity frequency(GF)was explored to re flect human health under di®erent three-dimensional(3D)depth information(mainly the negative disparity)displayed on a three-dimensional television(3D-TV)with shutter *** was obtained from 10 volunteers when they were watching 3D film segments with di®erent negative *** brain GF map shows that the depth information has a stronger in fluence on the frontal lobe than on the occipital *** regression analysis,nonlinear curve fittings of GF to RJD in Fp1,F3,O2 and T5 channels were mainly performed when RJD ranged from 0 to 3.4,while linearfittings were performed in some special RJD *** also confirms that RJD above 2.2 may lead to discomfort to human ***,it suggests a suitable RJD range for people to watch from the objective *** outcomes can be used as a guidance to decrease human discomforts induced by 3D production.

关键词： 3D-TV negative disparity human discomfort

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Periodic Solutions of Singular Second Order Equations at Resonance

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1599-1610页

作者： yin yin WU Ding Bian qian School of Mathematical Sciences Soochow University Department of Fondamental Courses Wuxi Institute of Technology

In this paper, we study the existence of positive periodic solutions for singular second order equations x＂＋ n2/4＋h（x） = p（t）, where h has a singularity at the origin and n is a positive integer. We give an explicit condition to ensure the existence of positive periodic solutions when h is an unbounded perturbation at infinity by using qualitative analysis and topological dezree theory.

关键词： Second order equations singularity periodic solutions resonance unbounded perturba-tions

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Single-atom Fe-N_(5)catalyst for high-performance zinc-air batteries

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Nano Research 2022年第9期15卷 8056-8064页

作者： Le Li yin-Juan Chen Hao-Ran xing Na Li Jia-Wei Xia xing-Yue qian Hui Xu Wei-Zuo Li Feng-Xiang yin Guang-Yu He Hai-Qun Chen Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterSchool of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China

Developing innovative and efficient non-precious-metal-group(non-PMG)electrocatalysts is crucial for the wide use of zinc-air batteries(ZABs).Herein,a single-atom catalyst(termed as Fe-N-C/rGO SAC)with unique five N-coordinated Fe(Fe-N_(5))centers is prepared by pyrolyzing the composite of zeolitic-imidazolate-frameworks-8(ZIF-8)and graphene oxide(GO).Specifically,the individual Fe site is stabilized by four equatorial and one axial N atoms donated by the N-doped carbon matrix and imidazole ring,respectively,thus forming an asymmetric electron depletion zone over the metal center,which can effectively promote the generation of reactive intermediates and accelerate the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)processes for *** rechargeable liquid ZAB with Fe-N-C/rGO catalyst exhibits an extremely high energy density(928.25 Wh·kg^(−1)),a remarkable peak power density(107.12 mW·cm^(−2)),and a long cycle life(400 h).Additionally,the corresponding flexible solid-state ZAB displays superior foldability and remarkable cycling *** work provides both experimental and theoretical guidance for rational design of non-PMG electrocatalyst-driven ZABs.

关键词： N-doped hierarchical porous carbon/rGO composite single-atom electrocatalyst five N-coordinated Fe(Fe-N_(5))singleatom sites zinc-air battery density functional theory(DFT)study

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Moments of inertia of neutron stars in relativistic mean field theory:The role of the isovector scalar channel

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Science China(Physics,Mechanics & Astronomy) 2018年第8期61卷 54-60页

作者： Zhuang qian RuoYu xing BaoYuan Sun School of Nuclear Science and Technology Lanzhou University

With the inclusion of the isovector scalar channel in the meson-nucleon couplings, taking DD-MEδ as an effective interaction, the moments of inertia of neutron stars possessing various stellar masses are studied within the density dependent relativistic mean field （RMF） theory. The isovector scalar channel contributes to the softening of the neutron-star matter equation of state （EOS） and therefore the reduction of the maximum mass and radius of neutron stars. Smaller values of the total moment of inertia 1 and the crustal moment of inertia AI are then obtained in DD-ME~ via numerical procedure in comparison with those in other selected RMF functionals. In addition, the involvement of the isovector scalar channel lowers the thickness of the neutron star crust and its mass fi＇action as well. The sensitivity to both the crustal mass and stellar radius causes the crustal moment of inertia to be more obviously reduced than the total one, eventually leading to a suppression on the fraction of crustal moment of inertia △I/I in DD-MFδ. The results indicate the crustal moment of inertia as a more sensitive probe of the neutron-star matter EOS than the total one, and demonstrate that the isovector scalar meson-nucleon couplings in the RMF theory could exert influence over the physics of pulsar glitches.

关键词： neutron star moment of inertia relativistic mean field theory isovector scalar channel

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