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

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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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Mutual-structure weighted guided image filtering for depth map restoration

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Optoelectronics Letters 2025年第1期21卷 51-56页

作者： LIU Zijian SONG Jian CHEN Quanmin XU Jiangtao Tianjin key Laboratory of Imaging and Sensing Microelectronic Technology School of Microelectronics Tianjin University Spikesee Technology Co. Ltd.

Although guided image filtering(GIF) is known for preserving edges and fast computation, it may produce inaccurate outputs in depth map restoration. In this paper, a novel confidence-weighted GIF called mutual-structure weighted GIF(MSWGIF) is proposed, which replaces the mean filtering strategy in GIF during handling overlapping windows. The confidence value is composed of a depth term and a mutual-structure term, where the depth term is utilized to protect the edges of the output, and the mutual-structure term helps to select accurate windows during the structure characteristics of the guidance image are transferred to the output. Experimental results show that MSWGIF reduces the root mean square error(RMSE) by an average of 12.37%, and the average growth rate of correlation(CORR) is 0.07% on average. Additionally, the average growth rate of structure similarity index measure(SSIM) is 0.34%.

关键词： Wiener filtering

Polybenzimidazolium-reinforced polyimide separators to inhibit dendrites for high-security lithium-ion batteries

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Science China Chemistry 2025年

作者： Guohua Sun Jiaqi Cui Qingsong Zhang Yisong Zhou Xinluo Li Yingying Zhang Zhanao Zhang Xin Zhang Jiantao Fan Pengpeng Li Lianlong Hou Nanjun Chen Hebei key Laboratory of Flexible Functional Materials School of Materials Science and Engineering Hebei University of Science and Technology State key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Academy for Advanced Interdisciplinary Studies Southern University of Science and Technology State key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University

Lithium dendrite formation poses a significant safety hazard in lithium-ion batteries（LIBs）, severely impeding their widespread adoption and further technological advancements. Here, we present a novel quaternized polybenzimidazolium（q-PBI） to armor polyimide（PI） nanofiber separator（q-PBI@PI）, in which the q-PBI containing lithiophilicity and anionphilicity sites serves as the multifunctional nano-layers to suppress the Li dendrite and reinforce the mechanical properties of PI nanofiber ***, the q-PBI@PI separator displays an unprecedented mechanical strength of 82.8 MPa, significantly outperforming previously reported PI nanofiber membranes（typically below 50.0 MPa）. Besides, we demonstrate that the q-PBI@PI separator simultaneously possesses low nucleation overpotential（59 mV） and exceptional average coulombic efficiency due to the suppression of Li dendrite. Importantly, q-PBI@PI-based Li||Li battery enables a stable Li plating-stripping at 1.0 m A cm-2for600 h. Attributing to these exceptional merits, the armored PI separator-based LIBs display remarkable specific capability and capacity retention. The density function theory calculations reveal that q-PBI is conducive to the desolvation of Li+and can immobilize Li+and PF6-ions near affinity sites of PI nanofibers for inhibiting the formation of Li dendrites. Our work paves a new avenue for the design of next-generation high-performing separators in LIBs.

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Copper homeostasis and neurodegenerative diseases

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Neural Regeneration Research 2025年第11期20卷 3124-3143页

作者： Yuanyuan Wang Daidi Li Kaifei Xu Guoqing Wang Feng Zhang International Research Laboratory of Ethnomedicine of Ministry of Education Key Laboratory of Basic Pharmacology of Ministry of EducationLaboratory Animal Center and Key Laboratory of Basic Pharmacology of Guizhou ProvinceZunyi Medical UniversityZunyiGuizhou ProvinceChina

Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of *** homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting beta(ATP7B),and the three copper chaperones ATOX1,CCS,and *** in copper homeostasis can lead to either the deficiency or accumulation of copper in brain *** evidence suggests that abnormal copper metabolism or copper binding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative ***,the exact mechanisms underlying these processes are not *** is a potent oxidant that increases reactive oxygen species production and promotes oxidative *** reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial *** oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory ***,copper can bind aberrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereby inducing neurotoxicity and ultimately cell *** study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-binding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease *** synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms by which copper contributes to a wide range of heredit

关键词： Alzheimer's disease amyotrophic lateral sclerosis disease copper homeostasis copper toxicity Huntington's disease Menkes'disease multiple sclerosis neurodegenerative disease Parkinson's disease Wilson's disease

Evaluating the impacts of converting grain to vegetable fields on nitrate transport in the deep vadose zone of the North China Plain

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Journal of Geographical Sciences 2025年第1期35卷 189-212页

作者： LIU Meiying MIN Leilei WU Lin ZHANG Yucui QI Yongqing WANG Shiqin LIU Binbin GENG Di SHEN Yanjun Hebei key Laboratory of Water-Saving Agriculture Key Laboratory of Agricultural Water ResourcesCenter for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyCAS School of Advanced Agricultural Sciences University of Chinese Academy of Sciences

Nitrate （NO3-） accumulation and transport processes in the thick vadose zone affect the evolution of the groundwater NO3-content in intensive agricultural *** land-use change （ALUC）,typically accompanied by substantial alterations in nitrogen fertilizer application and irrigation practices,is an important influencing *** study evaluated the changes in NO3-accumulation and transport in the deep vadose zone （DVZ,below the root zone）,and the groundwater NO3-content associated with ALUC from grain to vegetable fields in the North China Plain （NCP）.The ALUC from grain to vegetable resulted in nitrate–nitrogen （NO3--N） accumulation in DVZ increased by 235.5 kg ha-1m-1（163.2%） in the piedmont plain and 224.9 kg ha-1m-1（102.7%） in the central plain,*** change accelerated downward transport velocity in the DVZ (from 0.81±0.47 to 0.89±0.55 m yr-1in the piedmont plain,and from 0.24±0.12 to 0.92±0.12 m yr-1in the central plain) and increased NO3-leaching *** transport velocity and leaching fluxes resulted in chemical N-fertilizer entering the aquifer in several areas in the piedmont *** impact of the agricultural activity intensity changes,accompanied by the ALUC,on groundwater quantity and quality should be considered in similar regions.

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Effect of Bi/Si Ratio of BiBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 13-24页

作者： LIU Wei JIAO Jinxu LUO Dusha ZHOU Junjie SHI Lifen WANG Weiwei LI Changqing WANG Peng XIONG Dehua LI Hong State key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China State key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China

The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

关键词： Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi) Bi/Si ratio low-melting glass laser sealing vacuum glazing

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

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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

Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

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Neural Regeneration Research 2025年第3期20卷 779-793页

作者： Guangyong Zhang Qing Yao Chubing Long Pengcheng Yi Jiali Song Luojia Wu Wei Wan Xiuqin Rao Yue Lin Gen Wei Jun Ying Fuzhou Hua Department of Anesthesiology the Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina key Laboratory of Anesthesiology of Jiangxi Province NanchangJiangxi ProvinceChina

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

关键词： blood–brain barrier macrophages monocytes multiple sclerosis neuroinflammation review therapy

Lightweight Al-Nb-Ti-V-Cr high entropy alloys with high hardness and enhanced mechanical properties via doping Co

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China Foundry 2025年

作者： Fang-dong Xu De-zhi Chen Rui-run Chen Bin Gan Jing-yue Yu National key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Suzhou Laboratory

To develop high-hardness and high-strength lightweight high entropy alloys （LHEAs）,a series of CoxAlNbTiVCr alloys were *** phase constitution,distribution,and crystal structure of the Laves phase in alloys can be altered by adjusting the composition of HEAs,which in turn influences their mechanical *** Nb Ti VCr （x=0,0.5,1,1.5,and 2,atomic ratio percentage） LHEAs were designed and prepared to characterize the microstructure and tailor the mechanical *** introduction of Co changes the microstructure of LHEAs from a single B2 structure to a mixture dendrite structure,which consists of B2 phase,C14 and C15 Laves *** the C14 and C15 Laves phases exhibit coupled *** parameters including mixing enthalpy (ΔHmix),valence electron concentration （VEC）,atomic radius size （δ）,mixing entropy （ΔS）,and electronegativity difference （Δχ） are used to predict the formation of B2 and Laves phase in *** the Co content increases from 0 to 1.5at.%,Laves phase volume fraction gradually increases,which leads to an enhancement in the compressive strength from 1,520.8 MPa to 1,844.4 ***1.5Al Nb Ti VCr alloy exhibits the maximum Vickers hardness of 699.4 *** improvement of mechanical properties mainly originates from solid solution strengthening and second phase strengthening.

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