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Density-Functional Theories for Polyelectrolyte Systems

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Chinese Journal of Polymer Science 2024年第9期42卷 1302-1312,I0006页

作者： jia-Wei Zhang yu-Hang Zhang Bao-Hui Li Qiang Wang School of Physics Nankai UniversityTianjin90001China Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Polymer density-functional theories(PDFTs)have distinct advantages in the study of polyelectrolyte(PE)systems over experiments and molecular *** we give an introductory review of some PDFTs recently developed for PE *** start with a general formalism of PDFTs and its relation to the widely used polymer self-consistent field theory(SCFT),then explain the various correlations that are neglected in SCFT but can be accounted for in PDFTs,including those due to the excluded-volume interaction and chain connectivity of uncharged polymers,the electrostatic correlations of small ions,and the chain correlations in *** also list some applications of PDFTs for PE systems,and finally give some perspectives on future *** hope that our review can attract more researchers to apply and further develop PDFTs as a promising class of theoretical and computational tools.

关键词： Polymer density-functional theories Polyelectrolytes Correlations

Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China

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Chinese Geographical Science 2024年第3期34卷 519-532页

作者： HAN Nianlong yu Miao jia Peihong ZHANG yucheng HU Ke School of Geography and Tourism Huizhou UniversityHuizhou 516007China School of Public Administration Hainan Uni-versityHaikou 570228China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongChina School of Geographic Sciences and Remote Sensing Guangzhou UniversityGuangzhou 510006China School of Public Administration Nanjing Agricultural UniversityNanjing 210095China

Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the *** on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)*** dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their *** results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the ***,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural *** simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)*** maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened.

关键词： human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China

High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-yu Si Zhong-Liang Li Wen-Hong jia Lian Xue Hong-Xin Luo jian-Cai Xu Bai-Fei Shen lin-Gang Zhang Liang-Liang Ji yu-Xin Leng Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was *** result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet ***,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

Effects of acupuncture on hypothalamic–pituitary–adrenal axis:Current status and future perspectives

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Journal of Integrative Medicine 2024年第4期22卷 445-458页

作者： jia-yuan Zheng Jing Zhu yu Wang Zhan-zhuang Tian Department of Integrative Medicine and Neurobiology School of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceInstitutes of Brain ScienceInstitute of Acupuncture ResearchAcademy of Integrative MedicineShanghai Key Laboratory for Acupuncture Mechanism and Acupoint FunctionShanghai Medical CollegeFudan UniversityShanghai 200032China Department of Human Anatomy School of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China

The hypothalamic–pituitary–adrenal(HPA) axis is a critical component of the neuroendocrine system,playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus,hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA *** review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture.

关键词： Acupuncture Electroacupuncture Hypothalamic-pituitary-adrenal axis Mechanism Neurotransmitter microRNA

Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China

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Engineering 2024年第6期37卷 69-77页

作者： Hongwei yu Junrong Shao Huawei jia Diga Gang Baiwen Ma Chengzhi Hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Changjiang Survey PlanningDesign and Research Co.Ltd.Wuhan 430010China

Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution *** can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,potentially thre... 详细信息

Microplastics(MPs;linked to human activity to a great ***-throughput sequencing results showed that the composition and abundance of microorganisms also differed in snow samples from areas with different MP pollution characteristics,indicating a considerable difference in microbial functional *** may have an interference effect on the individual growth and functional expression of microorganisms in *** addition,the results showed that functional living areas(e.g.,landfills and suburban areas)in cities play an important role in the properties of *** instance,the highest abundance of MPs was found in thermal power plants,whereas the abundance of polymers per sample was significantly lower in the suburban *** MP contaminants hidden in snow can alter microbial structure and function and are therefore a potential threat to ecosystem health.

关键词： Human activities Snow Microplastics Microbial community Urban function Environmental effect

Unique electromagnetic wave absorber for three-dimensional framework engineering with copious heterostructures

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Journal of Materials Science & Technology 2024年第3期170卷 129-139页

作者： Liyuan yu Qianqian Zhu Zhiqiang Guo yuhang Cheng 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 College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China

In order to obtain high-performance electromagnetic wave absorbers,the adjustment of structure and components is *** on the above requirements,this system forms a three-dimensional frame structure consisting of MXene and transition metal oxides(TMOs)through efficient electrostatic *** three-dimensional network structure has rich heterojunction structures,which can cause a large amount of interface polarization and conduction losses in incident electromagnetic *** structures cause multiple reflections and scattering of electromagnetic waves,which is also an important reason for further increasing electromagnetic wave *** the doping ratio is 1:1,the system has the best impedance matching,the maximum effective absorption bandwidth(EAB max)can reach 5.12 GHz at 1.7 mm,and the minimum reflection loss(RL_(min))is-50.30 dB at 1.8 *** provides a reference for the subsequent formation of 2D-MXene materials into 3D materials.

关键词： MXene Three-dimensional frame Heterojunction structure Conduction loss Electromagnetic wave absorption

Adaptive detection of range-spread targets in homogeneous and partially homogeneous clutter plus subspace interference

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Journal of Systems Engineering and Electronics 2024年第1期35卷 43-54页

作者： jiaN Tao HE jia WANG Bencai LIU yu XU Congan XIE Zikeng Research Institute of Information Fusion Naval Aviation UniversityYantai 264001China Air Force Early Warning Academy Wuhan 430019China

Adaptive detection of range-spread targets is considered in the presence of subspace interference plus Gaussian clutter with unknown covariance *** target signal and interference are supposed to lie in two linearly independent subspaces with deterministic but unknown *** on the two-step criteria,two adaptive detectors based on Gradient tests are proposed,in homogeneous and partially homogeneous clutter plus subspace interference,*** of the proposed detectors exhibit theoretically constant false alarm rate property against unknown clutter covariance matrix as well as the power *** results show that,the proposed detectors have better performance than their existing counterparts,especially for mismatches in the signal steering vectors.

关键词： adaptive detection subspace interference constant false alarm rate Gradient test partially homogeneous environment

Quantitative Analysis of Frosting Characteristics on the Drip Tray of A Cryogenic Valve for LNG Ships

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China Ocean Engineering 2024年第4期38卷 572-585页

作者： BAI Xu CHEN Guan-yu DU yue XU Cao CHEN jia-jing School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Cryogenic valves play a crucial role in the production and transportation of liquefied natural gas(LNG),and are primarily responsible for efficiently controlling the inflow and outflow of LNG and regulating ***,due to their operation in low-temperature and high-humidity environments,crucial components such as drip trays are susceptible to frosting,which may lead to LNG leakage,thereby causing severe safety *** this study,the user-defined function(UDF)is employed to redevelop Fluent,which integrates the frost growth model with the Eulerian multiphase flow model,to conduct a quantitative analysis of frosting on drip trays of cryogenic *** effects of environmental parameters,such as wind speed,ambient temperature,air humidity,and cold surface temperature on the growth of the frost layer were *** study reveals a limiting wind speed between 1 m/s and 2 m/*** reaching this limit speed,the growth of the frost layer reaches its maximum,and further increases in the wind speed have no significant effect on the growth of the frost ***,the influence of the change in the flow field on droplet impingement and freezing during the growth of the frost layer is considered through the coupling method of the kinematic characteristics of water droplets and the collection coefficient of water *** study identifies the influence of different parameters on the droplet impact efficiency,leading to the modification of the frost layer on the drip tray.

关键词： LNG carrier drip tray frost effective impact coefficient

Tribological Behaviors of Electroless Nickel-Boron Coating on Titanium Alloy Surface

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 309-320页

作者： Yao jia jianping Lai jiaxin yu Huimin Qi Yafeng Zhang Hongtu He Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education State Key Laboratory of Environment-Friendly Energy MaterialsSouthwest University of Science and TechnologyMianyang 621010China

Titanium alloys are excellent structural materials in engineering fields,but their poor tribological properties limit their further *** plating is an effective method to enhance the tribological performance of alloys,but it is difficult to efficiently apply to titanium alloys,due to titanium alloy’s strong chemical *** this work,the electroless Nickel-Boron(Ni-B)coating was successfully deposited on the surface of titanium alloy(Ti-6AL-4V)via a new pre-treatment ***,linearly reciprocating sliding wear tests were performed to evaluate the tribological behaviors of titanium alloy and its electroless Ni-B *** was found that the Ni-B coatings can decrease the wear rate of the titanium alloy from 19.89×10^(−3)mm^(3)to 0.41×10^(−3)mm^(3),which attributes to the much higher hardness of Ni-B *** heat treatment,the hardness of Ni-B coating further increases corresponding to coating crystallization and hard phase ***,heat treatment does not improve the tribological performance of Ni-B coating,due to the fact that higher brittleness and more severe oxidative wear exacerbate the damage of heat-treated ***,the Ni-B coatings heat-treated both in air and nitrogen almost present the same tribological *** finding of this work on electroless coating would further extend the practical applications of titanium alloys in the engineering fields.

关键词： Electroless coating Titanium alloy Tribology Wear Heat treatment Nanoindentation