检索结果-南通市图书馆

Journal of Rare Earths 2025年第1期43卷 73-80,I0003页

作者： Xiao Man Ying chang Shaohong Guo Meilin Jia Jingchun Jia Inner Mongolia Key Laboratory of Green Catalysis and Inner Mongolia Collaborative Innovation Center for Water Environment Safety College of Chemistry and Environmental ScienceInner Mongolia Normal UniversityHohhot010022China

The development of an e fficacious and easily prepared no nprecious metal electrocatalyst is crucial for the oxygen reduction reaction(ORR).This work used a dual template method to prepare the amorphous rare earth-based catalyst PrO_(x)-NC,and optimized the calcination temperature and *** PrO_(x)-NC-900 catalyst has high durability and activity and exhibits superior ORR performance in alkaline electrolytes with an onset potential(E_(0))of 0.96 V and a half-wave potential(E_(1/2))of 0.85 *** research results indicate that the ORR performance of rare earth oxide composite carbon catalysts can be improved by adjusting oxygen vacancies(Ov).In addition,high specific surface area,N rich defect *** oxygen vacancies,and the synergistic effect of oxygen vacancies and N-doped carbon interfacial layer play a significant part in the enhancement of *** performance of the zinc air battery assembled with PrO_(x)-NC-900 is significantly improved,and rare earth oxides and carbon frameworks originating from metal organic frameworks(MOFs)contribute to the oxygen electrocatalyst and electron transfer rate of the zinc air *** catalyst provides promising information for the development of rare earth metal oxide nanostructures as potential candidate materials for ORR in alkaline media.

关键词： Rare earths Metal-organic framework Oxygen reduction reaction Zn-air batteries

维普期刊数据库

Status analysis on sputtering and erosion evaluation methods of ion optic systems

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2025年第1期38卷 254-270页

作者： Long MIAO Tongxun YANG Zhengxi ZHU chang LU Zhiwen WU Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China Advanced Aerospace Power and Energy Research Center Beijing Institute of TechnologyZhuhai 519088China

In the past few decades,ion engines have been widely used in deep-space propulsion and satellite *** aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion *** one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming *** this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid *** advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are *** different types of experimental methods of grid assembly erosion patterns are *** analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid ***,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime.

关键词： Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation

Size-dependent axisymmetric bending and buckling analysis of functionally graded sandwich Kirchhoff nanoplates using nonlocal strain gradient integral model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2025年第3期46卷 467-484页

作者： chang LI Hai QING State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and Astronautics

This paper extends the one-dimensional(1D) nonlocal strain gradient integral model(NStraGIM) to the two-dimensional(2D) Kirchhoff axisymmetric nanoplates,based on nonlocal strain gradient integral relations formulated along both the radial and circumferential directions. By transforming the proposed integral constitutive equations into the equivalent differential forms, complemented by the corresponding constitutive boundary conditions(CBCs), a well-posed mathematical formulation is established for analyzing the axisymmetric bending and buckling of annular/circular functionally graded(FG) sandwich nanoplates. The boundary conditions at the inner edge of a solid nanoplate are derived by L'H?spital's rule. The numerical solution is obtained by the generalized differential quadrature method(GDQM). The accuracy of the proposed model is validated through comparison with the data from the existing literature. A parameter study is conducted to demonstrate the effects of FG sandwich parameters, size parameters, and nonlocal gradient parameters.

关键词： Choquet integral

Advancements and challenges in esophageal carcinoma prognostic models:A comprehensive review and future directions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2025年第2期17卷 311-314页

作者： Jia Chen Qi-chang Xing Department of Clinical Pharmacy Xiangtan Central HospitalXiangtan 411100Hunan ProvinceChina The Affiliated Hospital Hunan UniversityChangsha 410082Hunan ProvinceChina

In this article,we comment on the article published by Yu et *** employing LASSO regression and Cox proportional hazard models,the article identified nine significant variables affecting survival,including body mass index,Karnofsky performance status,and tumor-node-metastasis *** firmly concur with Yu et al regarding the vital significance of clinical prediction models(CPMs),including logistic regression and Cox regression for assessment in esophageal carcinoma(EC).However,the nomogram's limitations and the complexities of integrating genetic factors pose *** integration of immunological data with advanced statistics offers new research ***-throughput sequencing and big data,facilitated by machine learning,have revolutionized cancer research but require substantial computational *** future of CPMs in EC depends on leveraging these technologies to improve predictive accuracy and clinical application,addressing the need for larger datasets,patientreported outcomes,and regular updates for clinical relevance.

关键词： Predictive model Machine learning Esophageal carcinoma Survival rate Factors

Spatiotemporal evolution of Ediacaran-Cambrian(ca.551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2025年第2期68卷 549-563页

作者： Yan YE Lei ZHANG Can CHEN Shan chang Yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Science China University of GeosciencesWuhan 430074China Department of Geology Lund UniversityLund 22362Sweden Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China Second Geological Brigade of Hubei Geological Bureau Enshi 445000China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China Exploration and Development Research Institute SINOPEC Jianghan Oilfield CompanyWuhan 430223China

The origin and evolution of sponges have attracted interest,not only because they are among the most basal metazoans,but also because they act as important ecological engineers in the *** research suggested that sponge groups diversified quickly during the Cambrian Series 2,while Terreneuvian sponge fossils are conspicuously rare and poorly ***,an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C,ca.551–523 Ma)transitional carbonates/cherts worldwide,particularly in South China,which calls for updated *** oxygenation has been widely proposed to play a critical role in organismal evolution,but its relationship with sponges is unclear and falls into a“chicken-egg”*** this study,we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous *** to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area,and then potentially expand to the continental shelf and deep basin in the lower *** these sections,the abundance,size,and diversity of monaxons increase upwards,followed by the appearance of diaxons,triaxons and then *** the uncertain affinity of the sponge fossils,it is possible that siliceous hexactinellids evolved later than siliceous demosponges,given that the earliest spicule assemblages are exclusively composed of monaxons,which commonly form bundles comparable to modern *** geochemical data from the Sifangjing section,Guizhou Province and the Yanziqiao section,Hunan Province,South China show that the appearance of sponges usually corresponds to anoxic *** addition,we applied the recently proposed Biological Pump,Oxygen and Phosphorus(BPOP)model to trace the evolution of oceanic oxygen concentrations with the radiation of *** results indicate that the possible contribution o

关键词： Cambrian Sponge Oxygenation Silicon concentration Box model

维普期刊数据库

同方期刊数据库

Pyrrolic nitrogen coordinated Ni^(2+) dual-atom catalyst for boosting CO_(2) electroreduction

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第2期68卷 570-579页

作者： Zhi-Wei Chen Hong-Juan Wang chang Liu Xiu-Li Lu Tong-Bu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Nitrogen-doped carbon materials have been widely used for the constructions of single-atom catalysts,while the effect of different species of doped nitrogen on the catalytic activity of CO_(2) electroreduction has rarely been *** we found that pyrrolic-N coordinated Ni2+catalysts display much higher electrocatalytic CO_(2)-to-CO activity and selectivity than the corresponding pyridinic-N coordinated low valent Ni^((0–+2))catalysts,and pyrrolic-N coordinated Ni2 dual-atoms catalyst of Ni2/N-CNTs exhibits the best electrocatalytic performance,with over 90%Faradaic efficiencies in a broad potentials from−0.6 to−1.2 V *** hydrogen electrode,as well as an outstanding CO specific current of 56.2 A/mgNi and high turnover frequency of 6.2×10^(4) h^(−1),over 7-times higher than those of pyridinic-N coordinated Ni *** results indicate the weak electron-donor nature of pyrrolic-N facilitates the generation of a reduced active site at low overpotential for boosting CO_(2) *** functional theory calculations reveal that the reaction free energy for the*COOH formation on pyrrolic-N coordinated Ni catalysts are lower than those on pyridinic-N coordinated Ni catalysts,and a H_(2)Oadsorbed Ni_(2)/N-CNTs displays the optimized reaction free energy for both*COOH formation and CO desorption,which derive the best catalytic performance.

关键词： dual-atom catalyst CO_(2) electroreduction synergistic catalysis pyrrolic-N pyridinic-N

Long-term trends and response of wet ammonia deposition to changes in anthropogenic emissions in the Pearl River delta of China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2025年第5期151卷 373-386页

作者： Mingyue Li Lyumeng Ye Ming chang Weihua Chen Shuidi He Buqing Zhong Xuemei Wang Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Institute for Environmental and Climate ResearchJinan UniversityGuangzhou 511443China South China Institute of Environmental Sciences The Ministry of Ecology and Environment of PRCGuangzhou 510530China Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China

The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium ***,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends and changes in wet NH_(4)^(+)-N deposition in response to emissions,which interferes with the ability to make effective *** study has analyzed the long-term trends of wet NH_(4)^(+)-N deposition flux and has quantified the effect of anthropogenic emissions and meteorological factors at a typical urban site and a typical forest site in the PRD region from 2009 to *** revealed a significant decreasing trend in wet NH_(4)^(+)-N flux in both the typical urban and forest areas of the PRD region,at-6.2%/year(pchange alone explained 10%–31%.NH_(3)emissions have the greatest impact on the urban area among anthropogenic emission factors,while SO_(2)emissions have the greatest impact on the forest ***,precipitation was identified as the primary meteorological driver for both *** findings also imply that the benefits of NH_(3)emissions reductions might not immediately emerge due to interference from weather-related factors.

关键词： Long-term trends Inter-annual variation Wet ammonium deposition Anthropogenic emission change Meteorological condition The Pearl River Delta region

Interconnections between diabetic corneal neuropathy and diabetic retinopathy:diagnostic and therapeutic implications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第8期20卷 2169-2180页

作者： Mingyi Yu Faith Teo En Ning chang Liu Yu-Chi Liu Tissue Engineering and Stem Cell Group Singapore Eye Research InstituteSingapore Yong Loo Lin School of Medicine National University of SingaporeSingapore Department of Cornea and External Eye Disease Singapore National Eye CenterSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Medical SchoolSingapore

Diabetic corneal neuropathy and diabetic retinopathy are ocular complications occurring in the context of diabetes *** corneal neuropathy refers to the progressive damage of corneal *** retinopathy has traditionally been considered as damage to the retinal ***,growing evidence suggests that diabetic retinopathy is a complex neurovascular disorder resulting from dysfunction of the neurovascular unit,which includes both the retinal vascular structures and neural *** retinopathy is one of the leading causes of blindness and is frequently screened for as part of diabetic ocular ***,diabetic corneal neuropathy is commonly overlooked and underdiagnosed,leading to severe ocular surface *** studies have found that these two conditions tend to occur together,and they share similarities in their pathogenesis pathways,being triggered by a status of chronic *** review aims to discuss the interconnection between diabetic corneal neuropathy and diabetic retinopathy,whether diabetic corneal neuropathy precedes diabetic retinopathy,as well as the relation between the stage of diabetic retinopathy and the severity of corneal *** also endeavor to explore the relevance of a corneal screening in diabetic eyes and the possibility of using corneal nerve measurements to monitor the progression of diabetic retinopathy.

关键词： cornea corneal nerves diabetes diabetic corneal neuropathy diabetic retinopathy retina

维普期刊数据库

Synthesis of intermetallic PtCo fuel cell catalysts from bimetallic core@shell structured nanoparticles

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第2期101卷 1-6页

作者： Le Zhang Lei Tong Shuai Li chang-Song Ma Kun-Ze Xue Hai-Wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China

The high activity and stability of intermetallic PtCo nanocatalysts toward oxygen reduction reaction make them a top candidate as low-Pt cathode catalysts in proton exchange membrane fuel cells（PEMFCs）.However,forming intermetallic structures typically requires high-temperature annealing,posing a challenge for achieving well-size control and highly ordered *** we report the design and synthesis of bimetallic co re@shell structured precursors for affording high-performance intermetallic PtCo *** fabrication of the core@shell precursor involves using a molecular ligand containing both sulfur and oxygen donors to selectively bind with Pt colloidal nanoparticles as the core and chelate Co ions as the *** high-temperature annealing,the ligand transforms into carbon coatings around alloy nanoparticles,preventing particle sintering;meanwhile,Co ions in the shell can easily diffuse into the Pt core,which helps to increase the thermodynamic driving force for forming intermetallic *** benefits enable us to obtain the catalyst with finely dispersed nanoparticles（～3.5 nm）and a high ordering degree of 72%.With 0.1 mgPt/cm2cathode loading,the catalyst delivers superior performance and durability in PEMFCs,showing an initial mass activity of 0.56 A/mgPt,an initial power density of 1.05 W/cm2at 0.67 V（H2-air）,and a voltage loss of 26 mV at 0.8 A/cm2after the accelerated durability test.

关键词： Bimetallic structure Fuel cells Intermetallic PtCo Oxygen reduction reaction

The interplay between histone modifications and nuclear lamina in genome regulation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2025年第1期52卷 24-38页

作者： chang Sun Yanjing Zhao Liping Guo Juhui Qiu Qin Peng Institute of Systems and Physical Biology Shenzhen Bay LaboratoryShenzhen 518132China Faculty of Medicine and Health Sciences Barcelona UniversityBarcelonaSpain Division of Life Science Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina School of Biology and Biological Engineering South China University of TechnologyGuangzhouGuangdong 510006China Key Laboratory for Biorheological Science and Technology of Ministry of Education State and Local Joint Engineering Laboratory for Vascular ImplantsCollege of BioengineeringChongqing UniversityChongqing 400030China

Gene expression is regulated by chromatin architecture and epigenetic remodeling in cell homeostasis and *** modifications act as the key factors to modulate the chromatin *** histone modifications are strongly associated with the localization of *** primarily localizes at the nuclear periphery,where it interacts with lamina proteins to suppress gene *** this review,we summarize the potential bridges that have regulatory functions of histone modifications in chromatin organization and transcriptional regulation at the nuclear *** use lamina-associated domains(LADs)as examples to elucidate the biological roles of the interactions between histone modifications and nuclear lamina in cell differentiation and *** the end,we highlight the technologies that are currently used to identify and visualize histone modifications and LADs,which could provide spatiotemporal information for understanding their regulatory functions in gene expression and discovering new targets for diseases.

关键词： Histone modifications Chromatin organization Nuclear lamina Lamina-associated domain Genome regulation Cell differentiation