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Supported Recyclable Metal-free Frustrated Lewis Pair Catalyst for Catalytic Hydrogenation of Substituted Pyridines to Piperidines

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Chemical Research in Chinese Universities 2024年第4期40卷 682-689页

作者： ma Shaohua TANG Zhiyong CAS Key Laboratory for Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

The construction of heterogeneous frustrated Lewis pairs(FLPs)catalysts is crucial for realizing highly efficient and recyclable pyridines catalytic *** this work,we prepared a recyclable heterogenous FLPs catalyst CMP-BF with conjugated microporous polymer CMP-ethynyl as the support via self-catalyzed 1.1.carboboration reaction with commercial Lewis acid B(C_(6)F_(5))_(3).The as-synthesized CMP-BF demonstrates superior heterogenous catalytic hydrogenation performance(conversion>99%),and considerable stability(84%conversion after three cycles)in recyclable hydrogenation of 2,*** work provides insights into the fabrication and catalytic application of recyclable heterogenous FLP catalysts.

关键词： Pyridine hydrogenation Frustrated Lewis pair Conjugated microporous polymer

Catalysis by subsurface metal atoms in Al(001. through electron transfer

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National Science Review 2024年第4期11卷 12-13页

作者： Bo Sun Ding ma Beijing National Laboratory for Molecular Science New Cornerstone Science Laboratory College of Chemistry and Molecular Engineering Peking University

Heterogeneous catalysis plays a crucial role in the chemical industry, which has evolved from the investigation of chemisorption to an electronic structure[1.. Diverse strategies, such as alloying,doping, and confining, have been applied to enhance the catalytic properties of active sites through electronic modulation. The electron transfer between active sites and substrates profoundly influences catalytic activity [2].

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Spatial Distribution Pattern and Influencing Factors of Bed-and-breakfasts(B&Bs)from the Perspective of Urban-rural Differences:A Case Study of Jiaodong Peninsula,China

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Chinese Geographical Science 2024年第4期34卷 752-763页

作者： WANG Xinyue ma Qian management College Ocean University of ChinaQingdao 266100China

There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial *** identifying the differences in spatial characteristics and influencing factors of each type,is essential for creating urban and rural B&B agglomeration *** study used density-based spatial clustering of applications with noise(DBSCAN)and the multi-scale geographically weighted regression(MGWR)model to explore similarities and differences in the spatial distribution patterns and influencing factors for urban and rural B&Bs on the Jiaodong Peninsula of China from 201. to *** results showed that:1.both urban and rural B&Bs in Jiaodong Peninsula went through three stages:a slow start from 201. to 201.,rapid development from 201. to 201.,and hindered development from 201. to ***,urban B&Bs demonstrated a higher development speed and agglomeration intensity,leading to an increasingly evident trend of uneven development between the two sectors.2)The clustering scale of both urban and rural B&Bs continued to expand in terms of quantity and *** B&B clusters characterized by a limited number,but a higher likelihood of transitioning from low-level to high-level *** the number of rural B&B clusters steadily increased over time,their clustering scale was comparatively lower than that of urban B&Bs,and they lacked the presence of high-level clustering.3)In terms of development direction,urban B&B clusters exhibited a relatively stable pattern and evolved into high-level clustering centers within the main urban ***,rural B&Bs exhibited a more pronounced spatial diffusion effect,with clusters showing a trend of multi-center development along the coastline.4)Transport emerged as a common influencing factor for both urban and rural B&Bs,with the density of road network having the strongest explanatory power for their spatial *** terms of differences,populati

关键词： urban-rural bed-and-breakfasts(B&Bs) spatiotemporal evolution density-based spatial clustering of applications with noise(DBSCAN)model multi-scale geographically weighted regression(MGWR) Jiaodong Peninsula China

Clinical applications of metagenomics next-generation sequencing in infectious diseases

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第6期25卷 471-484页

作者： Ying LIU Yongjun ma Department of Clinical Laboratory Affiliated Jinhua HospitalZhejiang University School of MedicineJinhua 321000China

Infectious diseases are a great threat to human *** and accurate detection of pathogens is important in the diagnosis and treatment of infectious *** next-generation sequencing(mNGS)is an unbiased and comprehensive approach for detecting all RNA and DNA in a *** the development of sequencing and bioinformatics technologies,mNGS is moving from research to clinical application,which opens a new avenue for pathogen *** studies have revealed good potential for the clinical application of mNGS in infectious diseases,especially in difficult-to-detect,rare,and novel ***,there are several hurdles in the clinical application of mNGS,such as:(1.lack of universal workflow validation and quality assurance;(2)insensitivity to high-host background and low-biomass samples;and(3)lack of standardized instructions for mass data analysis and report ***,a complete understanding of this new technology will help promote the clinical application of mNGS to infectious *** review briefly introduces the history of next-generation sequencing,mainstream sequencing platforms,and mNGS workflow,and discusses the clinical applications of mNGS to infectious diseases and its advantages and disadvantages.

关键词： Metagenomics next-generation sequencing(mNGS) Infectious disease Cerebrospinal fluid(CSF) Oxford Nanopore Technologies(ONT) Microbiome

Land-population-industry based village evolution and its influencing factors in the upper Tuojiang River

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Journal of Mountain Science 2024年第8期21卷 2790-2809页

作者： ZHAN Yunjun JI Yuxin HUANG Jiejun ma Changying ma Chuanqi School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China

With economic development and urbanization in China,the rural settlements have experienced great *** explore the evolution process of rural settlements in terms of land,population and industry can reveal the development law of rural spatial distribution,population structure and industrial economy in different stages and *** the development status and evolution characteristics of villages in the upper Tuojiang River basin in Southwest China in the past 20 years are of significant *** upper Tuojiang River basin includes the main types of terrain found in the Southwest region:mountainous,plains,and hills,exhibiting a certain typicality of geographical *** study took towns and townships at the town-level scale as the basic unit of research,and constructed an evaluation system for village evolution based on'land,population,and industry'.It employed Criteria Importance Through Inter-Criteria Correlation(CRITIC)analysis to examine the characteristics of village evolution in the area from 2000 to 2020,and used geographic detector analysis to identify the leading factors affecting village *** results show that:(1.From 2000 to 201.,villages in the upper Tuojiang River basin experienced significant changes,and the pace of these transformations slowed from 201. to 2020.(2)From a comprehensive perspective,from 2000 to 2020,villages in hilly areas show a decline,while villages in plain areas near the city center show a positive urbanization development.(3)Road accessibility and distance from the city center are the main factors that explain the spatial differentiation of village evolution degree in the study *** study elucidates the spatiotemporal evolution characteristics of villages in the upper Tuojiang River basin and identifies the primary factors contributing to their changes,which will provide a reference for investigating the development of rural areas in different terrains of Southwest China.

关键词： Village evolution Land Population Industry Geographic detector

Bioinspired nanomaterials for the treatment of bacterial infections

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Nano Research 2024年第2期17卷 691-714页

作者： Xiaojing ma Wenjing Tang Rong Yang Robert F.Smith School of Chemical&Biomolecular Engineering Cornell UniversityIthacaNY 14853USA

Infectious diseases pose a serious threat to global *** immunizations can control most viral infections,bacterial infections,particularly those caused by drug-resistant strains,continue to cause high rates of illness and ***,the creation of new antibiotics has come to a grinding halt in the last ten *** response to this crisis,nanotechnology has emerged as a hopeful solution to tackle drug resistance and enhance treatment results.A large variety of biomimetic nanomaterials,termed nanozymes,have demonstrated strong antimicrobial *** the inherent toxicity of nanomaterials is a concern,recent studies have harnessed the stimuli-responsiveness of nanomaterials to enable local and/or targeted delivery to reduce the treatment side ***,the physicochemical versatility of nanomaterials affords many degrees of freedom that enable rational design of smart or autonomous therapeutics,which cannot be achieved using conventional *** design straddles the fields of catalysis,nanoscience,microbiology,and translational *** provide an overview of this interdisciplinary landscape,this review is organized based on composition into lipid,metal,metal oxide,and non-metallic *** as a delivery vehicle enhance bioavailability and reduce ***-and metal oxide-based nanomaterials inhibit bacterial growth by mimicking natural enzymatic activities such as peroxidase(POD)and ***,carbon-,polymer-,and cell membrane-based nanomaterials are combined into a discussion on non-metallic *** the end of this review,potentially fruitful directions for future bioinspired nanomaterials in infectious disease treatment are included.

关键词： bioinspired nanomaterial bacteria infectious disease antimicrobial liposome nanozyme

Access to High-Molecular-Weight Polyethylenes through High Temperature Ethylene Polymerization Catalysed by Ethylene-Bridged ansa-(3-R-Cyclopentadienyl)(Fluorenyl) Zirconocene Complexes

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Chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： Bo Li Haiyan ma Jiling Huang Shanghai Key Laboratory of Functional materials Chemistry and Laboratory of Organometallic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of C1.symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(Zr: 1.5;Hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(maO) as the cocatalyst, zirconium complexes 1.5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×1.^(7) g PE·mol_(Zr)^(-1.·h^(-1. toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×1.^(5)-6.31.1.^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 1.0 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/Zr ratios, such as 1.5, polyethylenes with ultra high molecular weights up to 2.86×1.6 g/mol were obtained. It is worthy of noting that zirconium complexes 1.4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1.5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1.5. Zirconocene complexes 1.5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene Propylene Polymerization High temperature

Effects of baffle position in serpentine flow channel on the performance of proton exchange membrane fuel cells

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Chinese Journal of Chemical Engineering 2024年第5期69卷 250-262页

作者： Guodong Xia Xiaoya Zhang Dandan ma MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation Beijing Key Laboratory of Heat Transfer and Energy ConversionBeijing University of TechnologyBeijing 100124China

This study used a three-dimensional numerical model of a proton exchange membrane fuel cell with five types of channels:a smooth channel(Case 1.;eight rectangular baffles were arranged in the upstream(Case 2),midstream(Case 3),downstream(Case 4),and the entire cathode flow channel(Case 5)to study the effects of baffle position on mass transport,power density,net power,***,the effects of back pressure and humidity on the voltage were *** showed that compared to smooth channels,the oxygen and water transport facilitation at the diffusion layer-channel interface were added 1..53%-20.60%and 7.81.-9.80%at 1.68 A·cm^(-2)by adding *** closer the baffles were to upstream,the higher the total oxygen flux,but the lower the flux uniformity the worse the water *** oxygen flux of upstream baffles was 8.1.%higher than that of downstream baffles,but oxygen flux uniformity decreased by 1..96%at 1.68 A·cm^(-2).The order of water removal and voltage improvement was Case 4>Case 5>Case 3>Case 2>Case *** power of Case 4 was 9.87%higher than that of the smooth *** the Case 4,when the cell worked under low back pressure or high humidity,the voltage increments were *** potential increment for the back pressure of 0 atm was 0.9%higher than that of 2 atm(1.atm=1.1.325 kPa).The potential increment for the humidity of 1.0%was 7.89%higher than that of 50%.

关键词： Proton exchange membrane fuel cell Baffle position mass transfer Net power Uniformity Voltage increment

Shugan Jieyu capsule effects on peripheral blood micro-1.4, micro- 1.2, and brain-derived neurotrophic factor in patients with mild to moderate depression

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World Journal of Psychiatry 2024年第9期14卷 1354-1363页

作者： Xian Zhang Yang Liu Hua-Fei Tang Feng Jiang chun-Liang Chen Ting-Ting Wang Hui-Zhong Gu Qiang Zhao Rui ma Department of Pharmacy The 305 Hospital of People’s Liberation ArmyBeijing 100017China

BACKGROUND To assess the effectiveness of Shugan Jieyu capsules on peripheral blood miR-1.4,miR-1.2,and brain-derived neurotrophic factor(BDNF)levels in patients with mild to moderate depression following coronary artery intervention[percuta-neous coronary intervention(PCI)]for coronary heart *** with mild-to-moderate depression of the liver-qi stagnation type after PCI for coronary heart disease at the 305th Hospital of the People’s Liberation Army were enrolled from June 2022 to November 2023 and randomly assigned to two groups:Experimental(treated with Shugan Jieyu capsules)and control(tr-eated with escitalopram oxalate tablets).This study compared the antidepressant effects of these treatments using 1.-item Hamilton Rating Scale for Depression(HAMD-1.)scores,metabolic equivalents,low-density lipoprotein cholesterol,BDNF,high-sensitivity C-reactive protein levels,miR-1.4 and miR-1.2 levels,distribution of immune-related lymphocyte subsets,and traditional Chinese me-dicine syndrome scores before and after 6 weeks of *** No significant difference was observed in any index between the two groups before treatment(P>0.05).After treatment,the total efficacy rates were 93.33%and 90.00%in the experimental and control groups,*** group had significantly lower scores for the main and secondary syndromes compared to the control group(P0.05).The levels of low-density lipoprotein cholesterol,high-sensitivity C-reactive pro-tein,and miR-1.2 were significantly lower,whereas those of miR-1.4,BDNF,CD3+T lymphocytes,CD3+CD4+T helper lymphocytes,and CD3+CD4+/CD3+CD8+cells were significantly higher in the experimental group com-pared to the control group(P<0.05).The incidence of adverse reactions during experimental group was signi-ficantly lower than that in control group(P<0.05).CONCLUSION Shugan Jieyu capsu

关键词： Shugan Jieyu capsule Coronary heart disease Depression Escitalopram oxalate tablet Micro-1.4 Micro-1.2 Brain-derived neurotrophic factor