检索结果-南通市图书馆

Oxidative Molecular Layer Deposition Tailoring Eco-Mimetic Nanoarchitecture to Manipulate Electromagnetic Attenuation and Self-Powered Energy Conversion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2023年第9期15卷 224-237页

作者： Jin-Cheng Shu yan-lan zhang Yong Qin Mao-Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China Institute of Coal Chemistry State Key Laboratory of Coal ConversionChinese Academy of Sciences27 Taoyuan South RdTaiyuan 030001ShanxiPeople’s Republic of China

Advanced electromagnetic devices,as the pillars of the intelligent age,are setting off a grand transformation,redefining the structure of society to present pluralism and ***,the bombardment of electromagnetic radiation on society is also increasingly serious along with the growing popularity of"Big Data".Herein,drawing wisdom and inspiration from nature,an eco-mimetic nanoarchitecture is constructed for the first time,highly integrating the advantages of multiple components and structures to exhibit excellent electromagnetic *** electromagnetic properties and internal energy conversion can be flexibly regulated by tailoring microstructure with oxidative molecular layer deposition(oMLD),providing a new cognition to frequency-selective microwave *** optimal reflection loss reaches≈−58 dB,and the absorption frequency can be shifted from high frequency to low frequency by increasing the number of oMLD ***,a novel electromagnetic absorption surface is designed to enable ultra-wideband absorption,covering almost the entire K and Ka *** importantly,an ingenious self-powered device is constructed using the eco-mimetic nanoarchitecture,which can convert electromagnetic radiation into electric energy for *** work offers a new insight into electromagnetic protection and waste energy recycling,presenting a broad application prospect in radar stealth,information communication,aerospace engineering,etc.

关键词： Oxidative molecular layer deposition Eco-mimetic nanoarchitecture Microwave absorption Electromagnetic attenuation Self-powered energy conversion device

Relationship between hepatitis B virus DNA levels and liver histology in patients with chronic hepatitis B

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2007年第14期13卷 2104-2107页

作者： Jie Shao Lai Wei Hao Wang yan Sun lan-Fang zhang Jing Li Jian-Qiang Dong Department of Hepatic Disease People's Hospital Peking University Beijing 100034 China

AIM： To study the relationship between hepatitis B virus （HBV） DNA levels and liver histology in patients with chronic hepatitis B （CHB） and to determine the prevalence and characteristics of hepatitis B e antigen （HBeAg） negative patients.METHODS： A total of 213 patients with CHB were studied, and serum HBV DNA levels were measured by the COBAS Amplicor HBV Monitor test. All patients were divided into two groups according to the HBeAg *** correlation between serum HBV DNA levels and liver damage （liver histology and biochemistry） was explored.RESULTS： Of the 213 patients with serum HBV DNA levels higher than 10^5 copies/mL, 178 （83.6%） were HBeAg positive, 35 （16.4%） were HBeAg negative. The serum HBV DNA levels were not correlated to the age,history of CHB, histological grade and stage of liver disease in either HBeAg negative or HBeAg positive patients. There was no correlation between serum levels of HBV DNA and alanine aminotransferanse （ALT）,aspartate aminotrans-ferase （AST） in HBeAg positive patients. In HBeAg negative patients, there was no correlation between serum levels of HBV DNA and AST,while serum DNA levels correlated with ALT （r = 0.351, P = 0.042）. The grade （G） of liver disease correlated with ALT and AST （P 〈 0.05, r = 0.205, 0.327 respectively）in HBeAg positive patients. In HBeAg negative patients,correlations were shown between ALT, AST and the G （P 〈 0.01, and r = 0.862, 0.802 respectively）. HBeAg negative patients were older （35 ± 9 years vs 30 ±9 years, P 〈 0.05 ） and had a longer history of HBV infection （8 ± 4 years vs 6 ± 4 years, P 〈 0.05） and a lower HBV DNA level than HBeAg positive patients （8.4± 1.7 Log HBV DNA vs 9.8 ± 1.3 Log HBV DNA, P 〈0.001）. There were no significant differences in sex ratio,ALT and AST levels and liver histology between the two groups.CONCLUSION： Serum HBV DNA level is not correlated to histological grade or stage of liver disease in CHB patients with HBV DNA more than 10^5 copies/*** to HB

关键词： Hepatitis B virus Hepatitis B virus DNA Chronic hepatitis B Liver histology

Shape Memory Polymer Composites:4D Printing,Smart Structures,and Applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research 2024年第3期2023卷 319-343页

作者： Shiyu yan Fenghua zhang lan Luo Linlin Wang yanju Liu Jinsong Leng Centre for Composite Materials and Structures Harbin Institute of Technology(HIT)No.2 Yikuang StreetHarbin 150000People's Republic of China Department of Astronautic Science and Mechanics Harbin Institute of Technology(HIT)No.92 West Dazhi StreetHarbin 150000People's Republic of China.

Shape memory polymers (SMPs) and their composites (SMPCs) are smart materials that can be stably deformed and then return to their original shape under external stimulation, thus having a memory of their shape. Three-dimensional (3D) printing is an advanced technology for fabricating products using a digital software tool. Four-dimensional (4D) printing is a new generation of additive manufacturing technology that combines shape memory materials and 3D printing technology. Currently, 4D-printed SMPs and SMPCs are gaining considerable research attention and are finding use in various fields, including biomedical science. This review introduces SMPs, SMPCs, and 4D printing technologies, highlighting several special 4D-printed structures. It summarizes the recent research progress of 4D-printed SMPs and SMPCs in various fields, with particular emphasis on biomedical applications. Additionally, it presents an overview of the challenges and development prospects of 4D-printed SMPs and SMPCs and provides a preliminary discussion and useful reference for the research and application of 4D-printed SMPs and SMPCs.

关键词： composites printing Smart

Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao lan-Sheng Liu Jie Zhao yan-Xia Wang An-Zhi Ma Zheng-Rui Ma lan-Ying zhang Ruo-Chen lan College of Chemistry and Chemical Engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

Heterogeneous Image Knowledge Driven Visual Perception

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 255-257页

作者： lan yan Wenbo Zheng Fei-Yue Wang IEEE the College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China the School of Computer Science and Artificial Intelligence Wuhan University of TechnologyWuhan 430070China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Dear Editor,This letter is concerned with visual perception closely related to heterogeneous *** the huge challenge brought by different image modalities,we propose a visual perception framework based on heterogeneous image knowledge,i.e.,the domain knowledge associated with specific vision tasks,to better address the corresponding visual perception problems.

关键词： Visual visual knowledge

Self-assembly tungsten selenide hybrid ternary MOF derived magnetic alloys via multi-polarization to boost microwave absorption

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 1625-1635页

作者： Tianbao Zhao Tingting Zheng Di lan yan zhang Zhengshuo Sun Chao Wang Zirui Jia Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China

Confronted with severe electromagnetic wave pollution,the development of high-performance electromagnetic wave shielding or absorbing materials is an effective way to deal with ***,double transition metal alloys and transition metal dichalcogenides have attracted extensive attention in electromagnetic wave absorption,but few reports have studied the effects of these two materials on electromagnetic wave absorption at the same *** this work,cobalt-based alloy with magnetic loss mechanism was selected for composition *** ternary metal-organic framework was prepared by the one-step method,and then CoCu/C was prepared by high temperature ***,in the hydrothermal process,ultra-thin tungsten selenide nanosheets were coated on the surface of magnetic component,and the final polyhedral WSe_(2)/CoCu/C composites with multiple heterogeneous interfaces were *** synergistic effect of dielectric and magnetic components optimizes impedance matching and allows more electromagnetic waves to enter the ***,through the conduction loss of high conductivity graphitized carbon,interfacial polarization,and dipole polarization of heterogeneous interfaces between the components,the magnetic loss provided by CoCu alloy can work together to maximize the attenuation ability of electromagnetic ***,the minimum reflection loss(RLmin)value of the composite reaches-53.43 dB when the matched thickness is 2.1 mm,while the maximum effective absorption bandwidth(EABmax)reaches 6.0 GHz at a thin thickness of 1.8 *** work provides some support and reference for the design of novel electromagnetic wave absorbing materials via the dielectric/magnetic loss synergistic mechanism.

关键词： metal-organic framework dielectric/magnetic loss transition metal dichalcogenide electromagnetic wave absorption

Highly Transparent Fire-resistant Coatings with Intumescent Three-source Integration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第7期42卷 907-915,I0005页

作者： Xiao-Liang Zeng Xin-Sheng lan yan Wang Lin zhang De-Ming Guo Hai-Bo Zhao State Grid Sichuan Electric Power Research Institute Chengdu610041China The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(Ministry of Education) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu610064China

Wood,a readily available and sustainable natural resource,has found widespread use in construction and ***,its inherent flammability poses a potential fire *** intumescent fire-retardant coatings effectively mitigate this risk,achieving high transparency in such coatings presents a significant *** our approach,we employed a cross-linked network of phytic acid anion and N-[3-(trimethoxysilyl)propyl]-N,N,N-trimethylammonium cation to create a transparent"three-in-one"intumescent *** collaborative P/N/Si flame-retardant effect markedly improved the intumescent char-forming capability,preventing the wood from rapid *** resulted in a substantial reduction in heat release(13.9%decrease in THR)and an increased limiting oxygen index(LOI)value of 35.5%.Crucially,the high transparency of the coating ensured minimal impact on the wood's appearance,allowing the natural wood grains to remain clearly *** innovative approach provides a straightforward method for developing transparent intumescent flame-retardant coatings suitable for wooden *** potential applications extend to preserving ancient buildings and heritage conservation efforts.

关键词： Fire-resistant coating Flame retardancy Wood Transparency

Object Helps U-Net Based Change Detectors

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 548-550页

作者： lan yan Qiang Li Kenli Li College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Dear Editor,This letter focuses on leveraging the object information in images to improve the performance of the U-Net based change *** detection is fundamental to many computer vision *** existing solutions based on ... 详细信息

关键词： Net computer networks

Climate and topography regulate the spatial pattern of soil salinization and its effects on shrub community structure in Northwest China

在线全文

学校读者我要写书评

暂无评论

Journal of Arid land 2024年第7期16卷 925-942页

作者： DU lan TIAN Shengchuan ZHAO Nan zhang Bin MU Xiaohan TANG Lisong ZHENG Xinjun LI yan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Fukang Station of Desert Ecology Chinese Academy of SciencesFukang 831505China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China

Soil salinization may affect biodiversity and species composition,leading to changes in the plant community ***,few studies have explored the spatial pattern of soil salinization and its effects on shrub community structure at the ecosystem ***,we conducted a transect sampling of desert shrublands in Northwest China during the growing season(June–September)in *** salinization(both the degree and type),shrub community structure(e.g.,shrub density and height),and biodiversity parameters(e.g.,Simpson diversity,Margalf abundance,Shannon-Wiener diversity,and Pielou evenness indices)were used to assess the effects of soil salinization on shrub community *** results showed that the primary degree of soil salinization in the study area was light salinization,with the area proportion of 69.8%.Whereas the main type of soil salinization was characterized as sulfate saline soil,also accounting for 69.8%of the total ***,there was a significant reduction in the degree of soil salinization and a shift in the type of soil salinization from chloride saline soil to sulfate saline soil,with an increase in *** mean annual precipitation(MAP),mean annual evapotranspiration(MAE),elevation,and slope significantly contributed to soil salinization and its geochemical *** soil salinization intensified,shrub community structure displayed increased diversity and evenness,as indicated by the increases in the Simpson diversity,Shannon-Wiener diversity,and Pielou evenness ***,the succulent stems and leaves of Chenopodiaceae and Tamaricaceae exhibited clear advantages under these ***,regional climate and topography,such as MAP,MAE,and elevation,had greater effects on the distribution of shrub plants than soil *** results provide a reference for the origin and pattern of soil salinization in drylands and their effects on the community structure of halophyte shrub species.

关键词： soil salinization halophytes shrubland climate change biodiversity drylands Northwest China