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Stereoselectiveα-glycosylation with glcN_(3)Donors Enabled Collective Syntheses of Acinetobacter baumannii Capsular Polysaccharides K43,K47 and K88 Repeating Units

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Chinese Journal of Chemistry 2024年第14期42卷 1593-1598页

作者： Kunxiu shou Shanshan Liu Yunqin zhang guozhi Xiao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyUniversity of Chinese Academy of SciencesChinese Academy of SciencesKunmingYunnan650201 China

Collective syntheses of *** CPS K43,K47 and K88 repeating units have been accomplished via a newα-glycosylation method with glcN_(3) as donors,which features:1)mild reaction conditions,2)good to high yields,3)excellent *** synthetic route also highlights an orthogonal one-pot coupling strategy on the basis of glycosyl ortho-(1-phenylvinyl)benzoates for stereoselective constructions of both 1,2-trans and 1,2-cis glycosidic bonds,precluding the issues of aglycone transfer.

关键词： A baumanni CPS α-glycosylation method One-pot glycosylation 1,2-glcN bonds glycosyl ortho-(1-phenylvinyl)benzoates Carbohydrates Oligosaccharides Total synthesis

Risk evaluation for diabetic retinopathy in Chinese renalbiopsied type 2 diabetes mellitus patients

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1283-1291页

作者： shou-Yue Huang Qi-Wei Hu Ze-Wei zhang Ping-Yan Shen Qiong zhang Department of Ophthalmology Ruijin Hospital Affiliated Medical SchoolShanghai Jiao Tong UniversityShanghai 200025China Department of Nephrology Ruijin Hospital Affiliated Medical SchoolShanghai Jiao Tong UniversityShanghai 200025China

AIM:To investigate diabetic retinopathy(DR)prevalence in Chinese renal-biopsied type 2 diabetes mellitus(T2DM)patients with kidney dysfunction,and to further evaluate its relationship with diabetic nephropathy(DN)incidence and the risk factors for DR development in this ***:A total of 84 renal-biopsied T2DM patients were *** and imaging examinations were employed for DR *** information and clinical measures along with renal histopathology were analyzed for comparisons between the DR and non-DR *** factors on DR development were analyzed with multiple logistic ***:DR prevalence was 50%in *** incidences of DN,non-diabetic renal disease(NDRD)and mixed-type pathology were 47.6%,19.0%and 33.3%in the DR group respectively,while 11.9%,83.3%and 4.8%in the non-DR *** blood pressure,ratio of urinary albumin to creatine ratio,urinary albumin,24-hours urinary protein,the incidence and severity of DN histopathology were found statistically increased in the DR *** logistic regression analysis showed histopathological DN incidence significantly increased the risk of DR development[odds ratio(OR)=21.664,95%confidential interval(CI)5.588 to 83.991,Pference to (NDRD)],wherein DN severity positively ***:Renal histopathological evidence indicates DN incidence and severity increases the risk of DR development in Chinese T2DM patients inexperienced of regular fundus examinations.

关键词： diabetic retinopathy diabetic nephropathy vision threatens renal biopsy vision screening

Spin effect on redox acceleration and regioselectivity in fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-Hong Li Tian-zhang Qiao Yi-Lin Lu shou-fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

Development of lithium-free P2-type high-sodium content cathode materials with enhanced cycle and air stability for sodium-ion batteries

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Rare Metals 2024年第1期43卷 113-123页

作者： Jin-Lv Tian Lin-Rong Wu Hai-Jun Zhao shou-Dong Xu Liang Chen Ding zhang Xiao-Chuan Duan College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Chemistry Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430205China

The effect of partial substitution of Mg for Ni on a high-sodium and lithium-free layered P2-type Na_(45/54)Mg_(6)/_(54)Ni_(12/54)Mn_(34/54)O_(2) cathode with high initial Coulombic efficiency and excellent cyclic stability has been investigated in this *** on the crystal structural analysis,the Mg doping can retain the P2 structure up to 4.3 V,thus restraining the detrimental phase transformation of P2-02during the Na-ion intercalation/deintercalation ***,the obtained Mg-doped P2-type cathode exhibits a reversible specific capacity of 109 mAh·g^(-1) at 0.1C between 2.0 and 4.3 V and a retention rate of 81.5% after 200cycles at *** addition,the full cell consisting of Mg-doped P2-type cathode and hard carbon anode shows a capacity retention rate of 85.6% after 100 *** study provides new insight into the development of durable cathode materials for sodium-ion batteries.

关键词： Sodium-ion batteries Cathode material High sodium content Air stability

Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

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Biomedical and Environmental Sciences 2024年第2期37卷 196-203页

作者： WANg Dan Dan WANg An Xin zhang Xiao Li WEI Wen Bin WU shou Ling ZHAO Xing Quan Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China China National Clinical Research Center for Neurological Diseases Beijing 100070China Beijing Tongren Eye Center Beijing Key Laboratory of Ophthalmology and Visual ScienceBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Department of Cardiology Kailuan HospitalTangshan 063001HebeiChina

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population *** study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular *** We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or *** regression was used to analyze the relationship between retinal metrics and cognitive *** stratified by different vascular statuses were also *** RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(Pge vessel *** underlying small vessel change in RNFL and CI should be investigated in the future.

关键词： Retinal nerve fiber layer Cognitive impairment Polyvascular abnormality

Constructing a 3D multichannel structure to enhance performance of Ni–Co–Mn hydroxide electrodes for flexible supercapacitors

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Rare Metals 2024年第1期43卷 148-163页

作者： Zhi-Hui Xu Shi-Shuai Sun Xue-Lei Li Zhi-Hui zhang Hai-Ying Li Shuang-Ting Ruan shou-gen Yin Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)and Tianjin Key Laboratory for Photoelectric Materials and Devices School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China College of Science Tianjin University of TechnologyTianjin 300384China School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China

The balancing of the electrochemical performance,mechanical stability,and processing technology for applying supercapacitors to flexible and wearable electronics continues to encounter severe ***,we prepare Ni-Co-Mn hydroxide electrodes with a threedimensional multichannel structure via a simple hydrothermal *** are constructed using vertically contiguous nano sheets with a uniform thickness and rough *** electrodes can provide numerous electroactive sites and accelerate the transmission of electrolyte *** relationship between the structure and electrochemical performances is verified by experiments and theoretical ***-dimensional(2D)planar and one-dimensional(1D)fiber electrodes are prepared using a flexible carbon cloth(CC)and carbon fiber(CF),respectively,as *** assembled quasi-solid-state flexible asymmetric supercapacitor(FASC)with a twodimensional sandwich structure using NiCoMn-OH/CC as the electrode achieves a remarkable energy density of73.8 Wh·kg^(-1)at a power density of 1.03 kW·kg^(-1).The quasi-solid-state FASC with a 1D linear structure using NiCoMn-OH/CF as the electrode also attains a high energy density(12.9 Wh·kg^(-1)at a power density of0.75 W·kg^(-1)).Moreover,the electrochemical performances of the NiCoMn/CC//AC/CC and NiCoMn/CF//AC/CF FASCs are not disturbed at different bending angles(0°,45°,90°,135°and 180°),This indicates the superior flexibility of the *** also assemble a self-powered energy-harvesting storage system by integrating FASCs and commercial solar cells to verify its *** displays sustainable development potential for energy storage.

关键词： Supercapacitors Flexible Ni–Co–Mn hydroxide 3D multichannel structure High performances

Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： Yun-Peng Li Hao-Ran Shen Shao-Juan Wang Hao zhang Jian Hu Rui Xin Xiao-Li Sun shou-Ke Yan Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

Cardo poly (ether sulfone) toughened E51/DETDA epoxy resin and its carbon fiber composites

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新型炭材料（中英文） 2024年第4期39卷 681-691页

作者： WU Rong-peng zhang Xing-hua WEI Xing-hai JINg De-qi SU Wei-guo zhang shou-chun Research Center of Advanced Thermoplastic Composites Engineering Institute of Coal ChemistryChinese Academy SciencesTaiyuan 030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy SciencesTaiyuan 030001China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430033China

A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various *** investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfone)(PES-C)on E51/DETDA epoxy and its carbon fiber composites(CFCs).Scanning electron microscopy showed that the phase structures of PES-C/epoxy blends change from island(of dispersed phase)structures to bi-continuous structures(of the matrix)as the PES-C content increased,which is associated with reaction-induced phase *** adding 15 phr PES-C,the glass transition temperature(T_(g))of the blends increased by 51.5℃,and the flexural strength,impact strength and fracture toughness of the blends were improved by 41.1%,186.2%and 42.7%,*** improvements could be attributed to the phase separation structure of the PES-C/epoxy sys-tem.A PES-C film was used to improve the mode-II fracture toughness(g_(IIC))of *** g_(IIC) value of the 7μm PES-C film toughened laminate was improved by 80.3%compared to that of the control *** increase in g_(IIC) was attributed to cohesive failure and plastic deformation in the interleaving region.

关键词： Epoxy resin CFRP PES-C Toughness

Unveiling the surface-interface properties of perovskite crystals and pivotal regulation strategies

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Nano Research 2024年第5期17卷 3950-3981页

作者： Qin Li Ziyu Wang Junjie Ma Mengqi Han Peng gao Meng Cai Yiqiang zhang Yanlin Song shou Peng Henan Institute of Advanced Technology College of ChemistryZhengzhou UniversityZhengzhou 450001China Key Laboratory of green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing 100190China China National Building Material group Co. Ltd.Beijing 100036China State Key Laboratory of Advanced Technology for Float glass Beijing 100036China

Metal-halide perovskite solar cells have garnered significant research attention in the last decade due to their exceptional photovoltaic performance and potential for *** achieving remarkable power conversion efficiency of up to 26.1%,a substantial discrepancy persists when compared to the theoretical Shockley-Queisser(SQ)*** of the most serious challenges facing perovskite solar cells is the energy loss incurred during photovoltaic conversion,which affects the SQ limits and stability of the *** significant than the energy loss occurring in the bulk phase of the perovskite is the energy loss occurring at the ***,we provide a systematic overview of the physical and chemical properties of the ***,we delve into the underlying mechanism causing the energy deficit and structural degradation at the surface-interface,aiming to enhance the understanding of carrier transport processes and structural chemical ***,we systematically summarized the primary modulating pathways,including surface reconstruction,dimensional construction,and electric-field ***,we propose directions for future research to advance the efficiency of perovskite solar cells towards the radiative limit and their widespread commercial application.

关键词： perovskite solar cells surface-interface treatment defect modification dimensional design energy regulation heterojunction and homojunction