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Which Neighborhoods Have Easier Access to Online Home Delivery Services?A Spatiotemporal Accessibility Analysis in Nanjing,China

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Chinese Geographical Science 2024年第4期34卷 722-738页

作者： KONG Yu zhen Feng ZHANG Shanqi shen Lizhen School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Provincial Engineering Research Center of Smart City Planning and Digital Governance Nanjing 210093China

The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent *** on the spatial accessibility of OHDS are emerging,but few is known about the temporal dimension of OHDS accessibility as well as the geographic and socioeconomic differences in the spatiotemporal accessibility of *** study measures the spatiotemporal accessibility of four types of OHDS,namely leisure,fresh and convenient,medical,and catering *** geographic and socioeconomic disparities in the spatiotemporal accessibility of these four types of OHDS are then identified using spatial statistical methods and the Kruskal-Wallis test(K-W test).The case study in Nanjing,China,suggests that:1)spatiotemporal accessibility better reflects the temporal variation of OHDS accessibility and avoids overestimation of OHDS accessibility when only considering its spatial dimension.2)The spatiotemporal accessibility of OHDS varies geographically and *** located in the main city or neighborhoods with higher housing prices,higher population density,and higher point of interest(POI)mix have better OHDS spatiotemporal *** study contributes to the understanding of OHDS accessibility from a spatiotemporal perspective,and the empirical insights can assist policymakers in creating intervention plans that take into account variations in OHDS spatiotemporal accessibility.

关键词： online home delivery services(OHDS) spatiotemporal accessibility neighborhoods accessibility differences Nanjing City China

Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method

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Nuclear Science and Techniques 2024年第5期35卷 200-215页

作者： Yi-sheng Hao zhen Wu shen-shen Gao Rui Qiu Hui Zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging of Ministry of Education Beijing 100084China Nuctech Company Limited Beijing 100084China

Global variance reduction is a bottleneck in Monte Carlo shielding *** global variance reduction problem requires that the statistical error of the entire space is *** study proposed a grid-AIS method for the global variance reduction problem based on the AIS method,which was implemented in the Monte Carlo program *** proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation *** results from the VENUS-Ⅲ benchmark problem showed that the grid-AIS method achieved a significant reduction in the variance of the statistical errors of the MESH grids,decreasing from 1.08×10^(-2) to 3.84×10^(-3),representing a 64.00% *** demonstrates that the grid-AIS method is effective in addressing global *** results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational ***,the grid-AIS method exhibited a computational efficiency approximately one order of magnitude higher than that of the AIS method and approximately two orders of magnitude higher than that of the conventional Monte Carlo method.

关键词： Monte Carlo Global variance reduction Reactor shielding Automatic importance sampling

Extraordinary hot extreme in summer 2022 over the Yangtze River basin modulated by the La Nina condition under global warming

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Advances in Climate Change Research 2024年第1期15卷 21-30页

作者： zhen LIAO Yu-Feng YUAN Yang CHEN Pan-mao ZHAI State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

A widespread and prolonged hot extreme hit the Yangtze River basin in summer 2022,with 300 sites established new temperature records and nearly 96%stations endured more than 40 hot *** the perspective of the combination effect of the global warming and La Nina condition,potential mechanisms of the hot extreme were *** a record-breaking hot extreme was caused by an extremely strong and westward-shifted western Pacific subtropical high(WPSH).The global warming effect contributed primarily to the abnormal hot days in the Yangtze River basin,coupled with the modulation of the La Nina *** sea surface temperature anomaly pattern under La Nina condition favored more convection activities over the western Pacific,encouraging an enhanced and westward-extended *** addition,an observation-based attribution analysis indicates that anthropogenic warming may increase the probability of such extensively persistent hot extremeby1.8 times.

关键词： Hot extreme The Yangtze River basin Global warming Tropical Pacific forcing

Ni-catalyzed highly regio- and stereo-selective diborylative cyclization of 1,6-enynes with diboron reagent

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Science China Chemistry 2024年第3期67卷 981-989页

作者： Qitao Guan zhen.shen.Yiqiang Tian Genping Huang Chun Zhang Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic ScienceDepartment of ChemistrySchool of SciencesTianjin UniversityTianjin 300072China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

The Ni-catalyzed highly selective diborylative cyclization of 1,6-enynes with diboron reagent has been developed. When pinB-Bdan was used, multiple types of boron-containing functional groups could be installed into organic molecule with great chemoselectivity and regioselectivity though this reaction. Meanwhile, if B_2pai_2 was employed, the asymmetric diborylative cyclization could be well induced by using strategy of dynamic kinetic resolution. Importantly, the above reactions could afford desired product with 100% atomic economy, and could be compatible with different series of substituents. The studies of further transformation well illustrated that different type products could serve diverse synthetic strategy. Notably, the reaction mechanism was intensively studied by density functional theory(DFT) calculations, which could reveal the mechanism of regio- and enantio-selective control.

关键词： nickel-catalyzed organoboron cyclization regioselectivity enantioselectivity

A review on Bi_(2)WO_(6)-based photocatalysts synthesis, modification, and applications in environmental remediation, life medical, and clean energy

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 87-108页

作者： Wei mao Xuewu shen Lixun Zhang Yang Liu Zehao Liu Yuntao Guan Guangdong Provincial Engineering Technology Research Center for Urban Water Cycle and Water Environment Safety Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China State Environmental Protection Key Laboratory of Microorganism Application and Risk Control School of EnvironmentTsinghua UniversityBeijing 100084China

Photocatalysis has emerged a promising strategy to remedy the current energy and environmental crisis due to its ability to directiy convert clean solar energy into chemical *** tungstate(Bi_(2)WO_(6))has been shown to be an excellent visible light response,a well-defined perovskite crystal structure,and an abundance of oxygen atoms(providing efficient channels for photogenerated carrier transfer)due to their suitable band gap,effective electron migration and separation,making them ideal *** has been extensively applied as photocatalyst in aspects including pollutant removal,carbon dioxide reduction,solar hydrogen production,ammonia synthesis by nitrogen photocatalytic reduction,and cancer *** this review,the fabrication and application of Bi_(2)WO_(6) in photocatalysis were comprehensively *** photocatalytic properties of BizwO-based materials were significantly enhanced by carbon modification,the construction of heterojunctions,and the atom doping to improve the photogenerated carrier migration rate,the number of surface active sites,and the photoexcitation ability of the *** addition,the potential development directions and the existing challenges to improve the photocatalytic performance of Bi_(2)WO_(6)-based materials were discussed.

关键词： Bismuth tungstate Synthesis and modification Photocatalytic application Environmental remediation Clean energy Medical science

City Network Evolution Characteristics of Smart Industry: Evidence from Yangtze River Delta, China

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Chinese Geographical Science 2024年第5期34卷 829-848页

作者： shen Lizhen ZHONG Zhaocheng CHEN Cheng ZHANG Shanqi zhen Feng School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Hefei Urban Planning&Design Institute Hefei 230041China

The dual-path model of industrial evolution and spatial progression has been widely acknowledged and incorporated into the strategic planning to promote the development of urban industries and regional ***,current research on inter-enter-prise city networks mainly focuses on the single sector of flows on all enterprise branches,such as product value chains and production factors,but neglects that of particular industry *** upon the new economic geography and city networks theory,this paper develops a methodological framework that focuses on the analysis of city network evolution characteristics of smart ***-larly,a conceptual model of smart industry enterprise-industry-city is proposed and then applied to a case study of smart industry in the Yangtze River Delta Region,*** enterprise supplier-customer data,a city network of smart industry is constructed and sub-sequently analyzed with the proposed *** indicate that the smart industry network in Yangtze River Delta Region exhibits a hierarchical structure and the expansion of the network presents a small-world network *** study not only makes a meth-odological contribution for revealing the industrial and spatial evolution path of the current smart industry,but also provides empirical support for the formulation of new economic development policies focused on smart industries,demonstrating the role of city clusters as carriers of regional synergistic development.

关键词： smart industry city networks social network analysis methodological framework Yangtze River Delta,China

Biomimetic design of highly flexible metal oxide nanofibrous membranes with exceptional mechanical performance for superior phosphopeptide enrichment

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Nano Research 2024年第5期17卷 4270-4278页

作者： Xue mao zhen-zhen Li Dong-Lian Hao Wei-Dong Han Gao-Peng Li Yao-Yu Wang Kun Zhang School of Textile Science and Engineering Key Laboratory of Functional Textile Material and Product(Ministry of Education)Xi’an Polytechnic UniversityXi’an 710048China Key Laboratory of Magnetic Molecules&Magnetic Information Materials of the Ministry of Education School of Chemistry&Material ScienceShanxi Normal UniversityTaiyuan 030031China Department of Clinical Laboratory The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004China Shanghai iProteome Biotechnology Co. LtdShanghai 201210China College of Chemistry&Materials Science Northwest UniversityXi'an 710127China

Developing free-standing and mechanical robust membrane materials capable of superior enrichment of phosphopeptides for analyzing and identifying the specific phosphoproteome of cancer cells is significant in understanding the molecular mechanisms of cancer development and exploring new therapeutic approaches,but still a significant challenge in materials *** this end,we firstly constructed highly flexible ZrTiO_(4) nanofibrous membranes(NFMs)with excellent mechanical stability through a cost-effective and scalable electrospinning and subsequent calcination ***,to further increase the enrichment capacity of the phosphopeptide,the biomimetic TiO_(2)@ZrTiO_(4) NFMs with root hair or leaf like branch microstructure are developed by the hydrothermal post-synthetic modification of ZrTiO_(4) NFMs through growing unfurling TiO_(2) nanosheets onto the ZrTiO_(4) ***,remarkable flexibility and mechanical stability enable the resulting TiO_(2)@ZrTiO_(4) NFMs excellent practicability,while the biomimetic microstructure allows it outstanding enrichment ability of the phosphopeptide and identification ability of the specific phosphoproteins in the digest of cervical cancer ***,6770 phosphopeptides can be enriched by TiO_(2)@ZrTiO_(4) NFMs(2205 corresponding phosphoproteins can be identified),and the value is much higher than that of ZrTiO_(4) NFMs(6399 phosphopeptides and 2132 identified phosphoproteins)and commercial high-performance TiO_(2) particles(4525 phosphopeptides and 1811 identified phosphoproteins).These results demonstrate the super ability of TiO_(2)@ZrTiO_(4) NFMs in phosphopeptide enrichment and great potential for exploring the pathogenesis of cancer.

关键词： inorganic nanofibers flexible ceramic nanofibrous membranes biomimetic materials exceptional mechanical performance flexibility

Enhanced hepatic metabolic perturbation of polystyrene nanoplastics by UV irradiation-induced hydroxyl radical generation

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Journal of Environmental Sciences 2024年第8期142卷 259-268页

作者： Shiyu He Jingran Wang Lihong Zhou zhen mao Xiaodan Zhang Jin Cai Peili Huang School of Public Health and Beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China

The environmental behavior of and risks associated with nanoplastics(NPs)have attracted considerable ***,compared to pristine NPs,environmental factors such as ultraviolet(UV)irradiation that lead to changes in the toxicity of NPs have rarely been *** evaluated the changes in morphology and physicochemical properties of polystyrene(PS)NPs before and after UV irradiation,and compared their hepatotoxicity in *** results showed that UV irradiation caused particle size reduction and increased the carbonyl index(CI)and negative charge on the particle ***-aged PS NPs(aPS NPs)could induce the generation of hydroxyl radicals(·OH),but also further promoted the generation of·OH in the Fenton reaction *** pathological damage was more severe in mice exposed to aPS NPs,accompanied by a large number of vacuoles and hepatocyte balloon-like changes and more marked perturbations in blood glucose and serum lipoprotein,alanine aminotransferase and aspartate aminotransferase *** addition,exposure to PS NPs and aPS NPs,especially aPS NPs,triggered oxidative stress and significantly damaged the antioxidant capacity of mice *** with PS NPs,exposure to aPS NPs increased the number of altered metabolites in hepatic and corresponding metabolic pathways,especially glutathione *** research suggests that UV irradiation can disrupt the redox balance in organisms by promoting the production of·OH,enhancing PS NPs-induced liver damage and metabolic *** study will help us understand the health risks of NPs and to avoid underestimation of the risks of NPs in nature.

关键词： Polystyrene nanoplastics Ultraviolet-aged nanoplastics Metabolic pathway Metabolomics Hydroxyl radical

Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： Xin Fu zhen Lu shen Li zheng-Hong Luo Lin-Xi Hou Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps