检索结果-南通市图书馆

Molecular recognition of cyclophanes in water

Chinese Chemical Letters 2024年第5期35卷 32-44页

作者： Fang-yuan Chen Wen-Chao Geng Kang Cai Dong-Sheng guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China College of Chemistry Nankai UniversityTianjin 300071China

Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular *** mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular *** the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition *** them,cyclophanes represent an important family of macrocyclic receptors that have been extensively *** aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous *** by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous *** review provides an overview of cyclophane receptors designed to bind organic guests in *** categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and *** review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.

关键词： Biomimetic receptor Cyclophane Molecular recognition Hydrophobic effect High-affinity Macrocycles

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of diamond particle size on microstructure and properties of diamond/Al-12Si composites prepared by vacuum-assisted pressure infiltration

引用

China Foundry 2024年第4期21卷 360-368页

作者： Jia-ping Fu Can-xu Zhou guo-fa Mi yuan Liu School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454100HenanChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

Diamond/aluminium composites have attracted attention in the field of thermal management of electronic packaging for their excellent *** order to solve the interfacial problem between diamond and aluminium,a novel process combining pressure infiltration with vacuum-assisted technology was proposed to prepare diamond/aluminum *** effect of diamond particle size on the microstructure and properties of the diamond/Al-12Si composites was *** results show that the diamond/Al-12Si composites exhibit high relative density and a uniform *** thermal conductivity and coefficient of thermal expansion increase with increasing particle size,while the bending strength exhibits the opposite *** the average diamond particle size increases from 45μm to 425μm,the thermal conductivity of the composites increases from 455 W·m^(-1)·K^(-1)to 713 W·m^(-1)·K^(-1)and the coefficient of thermal expansion increases from 4.97×10^(-6)K^(-1)to 6.72×10^(-6)K^(-1),while the bending strength decreases from 353 MPa to 246 *** research demonstrates that high-quality composites can be prepared by the vacuum-assisted pressure infiltration process and the thermal conductivity of the composites can be effectively improved by increasing the diamond particle size.

关键词： diamond/aluminum composites thermal conductivity electronic packaging vacuum-assisted pressure infiltration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hollow Metal-Organic Framework/MXene/Nanocellulose Composite Films for Giga/Terahertz Electromagnetic Shielding and Photothermal Conversion

引用

Nano-Micro Letters 2024年第9期16卷 161-179页

作者： Tian Mai Lei Chen Pei‑lin Wang Qi Liu Ming‑guo Ma Research Center of Biomass Clean Utilization MOE Engineering Research Center of Forestry Biomass Materials and BioenergyBeijing Key Laboratory of Lignocellulosic ChemistryCollege of Materials Science and TechnologyBeijing Forestry UniversityBeijing 100083People’s Republic of China State Silica-Based Materials Laboratory of Anhui Province Bengbu 233000People’s Republic of China

With the continuous advancement of communication technology,the escalating demand for electromagnetic shielding interference(EMI)materials with multifunctional and wideband EMI performance has become *** the electrical and magnetic components and designing the EMI material structure have attracted extensive interest,but remain a huge ***,we reported the alternating electromagnetic structure composite films composed of hollow metal-organic frameworks/layered MXene/nanocellulose(HMN)by alternating vacuum-assisted filtration *** HMN composite films exhibit excellent EMI shielding effectiveness performance in the GHz frequency(66.8 dB at Kaband)and THz frequency(114.6 dB at 0.1-4.0 THz).Besides,the HMN composite films also exhibit a high reflection loss of 39.7 dB at 0.7 THz with an effective absorption bandwidth up to 2.1 ***,HMN composite films show remarkable photothermal conversion performance,which can reach 104.6℃under 2.0 Sun and 235.4℃under 0.8 W cm^(−2),*** unique micro-and macrostructural design structures will absorb more incident electromagnetic waves via interfacial polarization/multiple scattering and produce more heat energy via the local surface plasmon resonance *** features make the HMN composite film a promising candidate for advanced EMI devices for future 6G communication and the protection of electronic equipment in cold environments.

关键词： Metal-organic frameworks MXene Nanocellulose Electromagnetic shielding Photothermal conversion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Space truss construction modeling based on on-orbit assembly motion feature

引用

Chinese Journal of Aeronautics 2024年第3期37卷 365-379页

作者： Changjie ZHAO Weizhong guo Meng CHEN Jiaxing HU Youcheng HAN Rongfu lin State Key Lab of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Institute of Aerospace System Engineering Shanghai Shanghai 201109China

More space truss construction has been planned to develop and utilize space *** trusses are designed in the way of large-scale,complex,modular,and on-orbit *** meet the upcoming challenge of large-scale space infrastructure construction,it is necessary to study space truss automation design and robotic *** paper proposes an ordinal finite screw adjacency matrix model(OFSAMM),focusing on the relationship between assembly motions,to express and compute a space truss *** this model,a space truss is abstracted as a set of ordered assembly motions,each of which is recorded as a finite screw as the basic element of the truss and its *** operation of truss transformation is also derived under this ***,the truss configuration,the assembly sequence,the truss sub-assembly,the truss components,and the on-orbit assembly task can be expressed and calculated in a unified model,which is calculated and stores the truss topology and assembly with the minimum storage *** the end of this paper,we introduce how to synthesize and optimize space truss design through two *** study will help to improve design ***,it provides a theoretical basis for the automatic construction of space truss structures,especially in the next stage.

关键词： Adjacency matrix Finite screw On-orbit construction modeling Space applications Space trusses Topology design

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Scalable synthesis of A_2S_3 (A=Sb, Bi) submicro/nanowires using their powders via solvothermal proceeding

引用

Chinese Science Bulletin 2006年第6期51卷 655-660页

作者： JI Tianhao LIU Guanrao QI Xingyi YANG Qinglin DENG yuan guo lin Applied Chemistry Department School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing100083 China

Single-crystal A2S3 (A=Sb, Bi) nanowires were successfully prepared via using their powders as precursors by solvothermal proceeding. The reac-tion temperature and time as well as solvent strongly influence final A2S3 crystalline morphology and size. Experimental results show that Sb2S3 rods prepared in ethylene glycol are thicker than its wires with av-erage diameter of 400 nm prepared in the mixture solvent of ethylene glycol and ethylenediamine at 200 oC for 24 h. However, under the same reaction con-dition, uniform submicrowires of Bi2S3 with average diameter of 150 nm can be obtained. When reaction temperature is decreased to 150 oC and reaction time is 40 h, pure Sb2S3 wires cannot be prepared. The possible mechanism is briefly discussed for the transformation of the Sb2S3 powders to their wire-like crystals.

关键词：低维结构晶形转变硫化物半导体纳米线锑铋

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Targeting the adenosine A2A receptor for neuroprotection and cognitive improvement in traumatic brain injury and Parkinson's disease

引用

Chinese Journal of Traumatology 2024年第3期27卷 125-133页

作者： Yan Zhao yuan-guo Zhou Jiang-Fan Chen Department of Army Occupational Disease State Key Laboratory of TraumaBurns and Combined InjuryResearch Institute of SurgeryDaping HospitalArmy Medical University.Chongqing400042China The Molecular Neuropharmacology Laboratory and the Eye-Brain Research Center The State Key Laboratory of OphthalmologyOptometry and Vision ScienceWenzhou Medical UniversityWenzhou325035Zhejiang ProvinceChina Oujiang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)Wenzhou325035Zhejiang ProvinceChina

Adenosine exerts its dual functions of homeostasis and neuromodulation in the brain by acting at mainly 2 G-protein coupled receptors,called A1 and A2A *** adenosine A2A receptor(A2AR)antagonists have been clinically pursued for the last 2 decades,leading to final approval of the istradefylline,an A2AR antagonist,for the treatment of OFF-Parkinson's disease(PD)*** approval paves the way to develop novel therapeutic methods for A2AR antagonists to address 2 major unmet medical needs in PD and traumatic brain injury(TBI),namely neuroprotection or improving *** this review,we first consider the evidence for aberrantly increased adenosine signaling in PD and TBI and the sufficiency of the increased A2AR signaling to trigger neurotoxicity and cognitive *** further discuss the increasing preclinical data on the reversal of cognitive deficits in PD and TBI by A2AR antagonists through control of degenerative proteins and synaptotoxicity,and on protection against TBI and PD pathologies by A2AR antagonists through control of ***,we provide the supporting evidence from multiple human prospective epidemiological studies which revealed an inverse relation between the consumption of caffeine and the risk of developing PD and cognitive decline in aging population and Alzheimer's disease ***,the convergence of clinical,epidemiological and experimental evidence supports the validity of A2AR as a new therapeutic target and facilitates the design of A2AR antagonists in clinical trials for disease-modifying and cognitive benefit in PD and TBI patients.

关键词： Receptor,Adenosine A2A Adenosine A2 receptor antagonists Parkinson's disease Brain injuries,traumatic

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development of a droplet digital polymerase chain reaction assay for the sensitive detection of total and integrated HIV-1 DNA

引用

Chinese Medical Journal 2024年第6期137卷 729-736页

作者： lin yuan Zhiying Liu Xin Zhang Feili Wei Shan guo Na guo Lifeng Liu Zhenglai Ma Yunxia Ji Rui Wang Xiaofan Lu Zhen Li Wei Xia Hao Wu Tong Zhang Bin Su Beijing Key Laboratory for HIV/AIDS Research Clinical and Research Center for Infectious DiseasesBeijing Youan HospitalCapital Medical UniversityBeijing 100069China Beijing Institute of Hepatology Beijing Youan HospitalCapital Medical UniversityBeijing 100069China

Background:Total human immunodeficiency virus(HIV)DNA and integrated HIV DNA are widely used markers of HIV *** digital polymerase chain reaction(ddPCR)can be used for absolute quantification without needing a standard ***,we developed duplex ddPCR assays to detect and quantify total HIV DNA and integrated HIV ***:The limit of detection,dynamic ranges,sensitivity,and reproducibility were evaluated by plasmid constructs containing both the HIV long terminal repeat(LTR)and human CD3 gene(for total HIV DNA)and ACH-2 cells(for integrated HIV DNA).Forty-two cases on stable suppressive antiretroviral therapy(ART)were assayed in total HIV DNA and integrated HIV *** coefficient analysis was performed on the data related to DNA copies and cluster of differentiation 4 positive(CD4^(+))T-cell counts,CD8^(+)T-cell counts and CD4/CD8 T-cell ratio,*** assay linear dynamic range and lower limit of detection(LLOD)were also ***:The assay could detect the presence of HIV-1 copies 100%at concentrations of 6.3 copies/reaction,and the estimated LLOD of the ddPCR assay was 4.4 HIV DNA copies/reaction(95%confidence intervals[CI]:3.6-6.5 copies/reaction)with linearity over a 5-log_(10)-unit range in total HIV DNA *** the integrated HIV DNA assay,the LLOD was 8.0 copies/reaction(95%CI:5.8-16.6 copies/reaction)with linearity over a 3-log 10-unit *** HIV DNA in CD4^(+)T cells was positively associated with integrated HIV DNA(r=0.76,Plinical trials.

关键词： Human immunodeficiency virus HIV Integrated HIV-1 DNA Total HIV DNA Droplet digital polymerase chain reaction HIV reservoir Antiretroviral therapy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reinforcement Learning Navigation for Robots Based on Hippocampus Episode Cognition

引用

Journal of Bionic Engineering 2024年第1期21卷 288-302页

作者： Jinsheng yuan Wei guo Zhiyuan Hou Fusheng Zha Mantian Li Pengfei Wang lining Sun State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150001China Shenzhen Academy of Aerospace Technology Shenzhen 518057China School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

Artificial intelligence is currently achieving impressive success in all ***,autonomous navigation remains a major challenge for *** learning is used for target navigation to simulate the interaction between the brain and the environment at the behavioral level,but the Artificial Neural Network trained by reinforcement learning cannot match the autonomous mobility of humans and *** hippocampus–striatum circuits are considered as key circuits for target navigation planning and *** paper aims to construct a bionic navigation model of reinforcement learning corresponding to the nervous system to improve the autonomous navigation performance of the *** ventral striatum is considered to be the behavioral evaluation region,and the hippocampal–striatum circuit constitutes the position–reward *** this paper,a set of episode cognition and reinforcement learning system simulating the mechanism of hippocampus and ventral striatum is constructed,which is used to provide target guidance for the robot to perform autonomous *** with traditional methods,this system reflects the high efficiency of learning and better Environmental *** research is an exploration of the intersection and fusion of artificial intelligence and neuroscience,which is conducive to the development of artificial intelligence and the understanding of the nervous system.

关键词： Episode cognition Reinforcement learning Hippocampus Robot navigation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Multi-Time-Scale Variational Mode Decomposition-Based Robust Fault Diagnosis of Railway Point Machines Under Multiple Noises

引用

Chinese Journal of Electronics 2024年第3期33卷 814-822页

作者： Junqi LIU Tao WEN guo XIE yuan CAO Clive Roberts Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'an University of Technology The School of Electronic and Information Engineering Beijing Jiaotong University Birmingham Centre for Railway Research and Education University of Birmingham

The fault diagnosis of railway point machines(RPMs) has attracted the attention of engineers and *** have studies considered diverse noises along the *** fulfill this aspect,a multi-time-scale variational mode decomposition(MTSVMD) is proposed in this paper to realize the accurate and robust fault diagnosis of RPMs under multiple *** decomposes condition monitoring signals after coarse-grained processing in varying *** this manner,the information contained in the signal components at multiple time scales can construct a more abundant feature space than at a single *** the experimental validation,a random position,random type,random number,and random length(4R) noise-adding algorithm helps to verify the robustness of the *** adequate experimental results demoristrate the superiority of the proposed MTSVMD-based fault diagnosis.

关键词： Fault diagnosis Condition monitoring Noise Signal processing algorithms Aerospace electronics Rail transportation Robustness

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Blockchain-Based MCS Detection Framework of Abnormal Spectrum Usage for Satellite Spectrum Sharing Scenario

引用

China Communications 2024年第2期21卷 32-48页

作者： Ning Yang Heng Wang Jingming Hu Bangning Zhang Daoxing guo yuan Liu College of Communications Engineering Army Engineering UniversityNanjing 210007China

In this paper, the problem of abnormal spectrum usage between satellite spectrum sharing systems is investigated to support multi-satellite spectrum coexistence. Given the cost of monitoring, the mobility of low-orbit satellites, and the directional nature of their signals, traditional monitoring methods are no longer suitable, especially in the case of multiple power level. Mobile crowdsensing(MCS), as a new technology, can make full use of idle resources to complete a variety of perceptual tasks. However, traditional MCS heavily relies on a centralized server and is vulnerable to single point of failure attacks. Therefore, we replace the original centralized server with a blockchain-based distributed service provider to enable its security. Therefore, in this work, we propose a blockchain-based MCS framework, in which we explain in detail how this framework can achieve abnormal frequency behavior monitoring in an inter-satellite spectrum sharing system. Then, under certain false alarm probability, we propose an abnormal spectrum detection algorithm based on mixed hypothesis test to maximize detection probability in single power level and multiple power level scenarios, respectively. Finally, a Bad out of Good(BooG) detector is proposed to ease the computational pressure on the blockchain nodes. Simulation results show the effectiveness of the proposed framework.

关键词： blockchain hypothesis test mobile crowdsensing satellite communication spectrum sharing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：