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Journal of Environmental Sciences 2024年第2期136卷 390-399页

作者： Aihua Cheng yi He Xiaohe liu Chi He Department of Environmental Engineering College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China

Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater ***,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by *** prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the ***,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation ***,biochar can effectively promote cycling stability by limiting Fe *** work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.

关键词： Biomass Biochar Fenton reaction Fe_(3)O_(4)/FeS(Fe/S) Phenol degradation

Solvent transport dynamics and its effect on evolution of mechanical properties of nitrocellulose(NC)-based propellants under hot-air drying process

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Defence Technology（防务技术） 2024年第2期32卷 262-270页

作者： Enfa Fu Mingjun yi Qianling liu Zhenggang Xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094People's Republic of China

Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant ***,few research on solvent transport dynamics within NC-based propellants was reported,and its effect on the evolution of mechanical properties was not interpreted *** study is conducted to gain a comprehensive understanding of hot-air drying for NC-based propellants and clarify the effect of temperature on solvent transport behavior and further the change of mechanical properties during *** drying kinetic curves show the drying time required is decreased but the steady solvent content is increased and the drying rate is obviously increased with the increase of hot-air temperatures,indicating hot-air temperatures have a significant effect on drying kinetics.A modified drying model was established,and results show it is more appropriate to describe solvent transport behavior within NC-based ***,two linear equations were established to exhibit the relationship between solvent content and its effect on the change of tensile properties,and the decrease of residual solvent content causes an obvious increase of tensile strength and tensile modulus of propellant products,indicating its mechanical properties can be partly improved by adjustment of residual solvent *** outcomes can be used to clarify solvent transport mechanisms and optimize drying process parameters of double-based gun propellants.

关键词： Nitrocellulose-based propellants Solvent transport dynamics Mechanical properties Drying kinetics Effective solvent diffusion coefficient

Interaction of yttrium barrier and calcium-rich phase on production and properties of WC precursor powders and alloys

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Journal of Rare Earths 2024年第1期42卷 228-236,I0008页

作者： Wen He Dunqiang Tan Zhiqiang yi Zhiqiang liu School of Materials Science and Engineering Nanchang UniversityNanchang330031China Instrumental Analysis Center of Nanchang Hangkong University Nanchang330063China

In order to reduce or eliminate the adverse effects of calcium impurity,the interaction of Ca and rare earth Y co-doping on the preparation of WC-Co cemented carbides was investigated.X-ray diffraction,scanning electron microscopy and transmission electron microscopy were employed to analyze the phase compositions,particle sizes and morphologies of them,*** results show that the second type of"yttrium barrier effect"is observed and the adverse influence of Ca-rich phase on tungsten powder can be eliminated by *** flexural strength and fracture toughness of YG6-0.01%Ca+0.09%Y alloy are 2199.5 MPa and 11.49 MPa·m^(1/2),showing improvement of 6.5% and 2.7% compared to YG6 alloy,*** evolutions of Ca-rich phase and Y-rich phase at the every alloy preparation stage of WO_(3),W,WC and cemented carbides are ***,the strengthening mechanism of WC-Co cemented carbide with co-addition of Ca and Y is proposed.

关键词： Yttrium barrier effect Ca-rich phase WC-Co cemented Carbide Microstructures Mechanisms Rare earths

Allelic reprogramming of chromatin states in human early embryos

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National Science Review 2024年第3期11卷 58-71页

作者： Shenli Yuan lei Gao Wenrong Tao Jianhong Zhan Gang Lu Jingye Zhang Chuanxin Zhang Lizhi yi Zhenbo liu Zhenzhen Hou Min Dai Han Zhao Zi-Jiang Chen Jiang liu Keliang Wu Center for Reproductive Medicine Shandong University CAS Key Laboratory of Genome Sciences and Information Collaborative Innovation Center of Genetics and Development Beijing Institute of Genomicsand China National Center for BioinformationChinese Academy of Sciences University of Chinese Academy of Sciences CUHK-SDU Joint Laboratory on Reproductive Genetics School of Biomedical Sciences the Chinese University of Hong Kong Key Laboratory of Reproductive Endocrinology of the Ministry of Education Shandong University Center for Reproductive Medicine Ren Ji Hospital School of Medicine Shanghai Jiao Tong University CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

The reprogramming of parental epigenomes in human early embryos remains elusive. To what extent the characteristics of parental epigenomes are conserved between humans and mice is currently unknown. Here,we mapped parental haploid epigenomes using human parthenogenetic and androgenetic embryos. Human embryos have a larger portion of genome with parentally specific epigenetic states than mouse *** allelic patterns of epigenetic states for orthologous regions are not conserved between humans and mice. Nevertheless, it is conserved that maternal DNA methylation and paternal H3K27me3 are associated with the repression of two alleles in humans and mice. In addition, for DNA-methylation-dependent imprinting, we report 19 novel imprinted genes and their associated germline differentially methylated regions. Unlike in mice, H3K27me3-dependent imprinting is not observed in human early ***, allele-specific epigenomic reprogramming is different in humans and mice.

关键词： human embryo epigenetics reprogramming DNA methylation H3K27me3 chromatin accessibility

Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

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China Ocean Engineering 2024年第1期38卷 42-53页

作者： liu lei liu Jian-cheng LI Xin XU Li-xin ZHANG Xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

ROS Balance Autoregulating Core-Shell CeO_(2)@ZIF-8/Au Nanoplatform for Wound Repair

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Nano-Micro Letters 2024年第8期16卷 341-361页

作者： Xi Zhou Quan Zhou Zhaozhi He yi Xiao Yan liu Zhuohang Huang Yaoji Sun Jiawei Wang Zhengdong Zhao Xiaozhou liu Bin Zhou lei Ren Yu Sun Zhiwei Chen Xingcai Zhang The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005People’s Republic of China Department of Electronic Science Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance ResearchSchool of Electronic Science and EngineeringXiamen UniversityXiamen 361005People’s Republic of China John A Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA Department of Otorhinolaryngology Union Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022People’s Republic of China NO.1 Middle School Affiliated to Central China Normal University Wuhan 430223People’s Republic of China

Reactive oxygen species(ROS)plays important roles in living *** ROS is a double-edged sword,which can eliminate drug-resistant bacteria,but excessive levels can cause oxidative damage to cells.A core–shell nanozyme,Ce O_(2)@ZIF-8/Au,has been crafted,spontaneously activating both ROS generating and scavenging functions,achieving the multifaceted functions of eliminating bacteria,reducing inflammation,and promoting wound *** Au Nanoparticles(NPs)on the shell exhibit high-efficiency peroxidase-like activity,producing ROS to kill ***,the encapsulation of Ce O_(2) core within ZIF-8 provides a seal for temporarily limiting the superoxide dismutase and catalase-like activities of Ce O_(2) ***,as the ZIF-8 structure decomposes in the acidic microenvironment,the Ce O_(2) core is gradually released,exerting its ROS scavenging activity to eliminate excess ROS produced by the Au *** two functions automatically and continuously regulate the balance of ROS levels,ultimately achieving the function of killing bacteria,reducing inflammation,and promoting wound *** innovative ROS spontaneous regulators hold immense potential for revolutionizing the field of antibacterial agents and therapies.

关键词： Metal-organic framework(MOF) Reactive oxygen species(ROS) Cerium dioxide Au nanoparticles Wound healing

The History of Controlling and Treating Infectious Diseases in Ancient China

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Current Medical Science 2024年第1期44卷 64-70页

作者： Cui-ling liu Tao ZHOU Liang-bin CHENG David FISHER Khrystyna PRONYUK Erkin MUSABAEV yi-ping DANG lei ZHAO Department of Infectious Diseases Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Gastroenterology and Hepatology Huanggang Hospital of Traditional Chinese MedicineHubei University of Chinese MedicineHuanggang 438000China Clinical College of Traditional Chinese Medicine Hubei University of Chinese MedicineWuhan 430065China Department of Liver Diseases Hubei Hospital of Traditional Chinese MedicineWuhan 430061China Department of Medical Biosciences Faculty of Natural SciencesUniversity of the Western CapeBellvilleCape Town 7535South Africa Department of Infectious Diseases Bogomolets National Medical UniversityKyiv 02132Ukraine The Research Institute of Virology Ministry of HealthTashkent 100122Uzbekistan Department of Vascular Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Infectious diseases are the common enemies of *** the course of historical development,they persistently threaten human health and *** today,despite the developments in medical science,we cannot escape the fear and suffering caused by infectious *** in ancient or modern times,the source of infection,route of transmission,and a susceptible population are the three key conditions for the prevalence and spread of infectious *** factors closely related to these three conditions can affect the prevalence of infectious *** is one of the cradles of world *** ancient people accumulated a great deal of experience and lessons in the long struggle against infectious *** the face of the current threat posed by widespread infectious disease,it is imperative to review and summarize ancient Chinese ideas and health policies on epidemic prevention and control to inspire contemporary efforts in the prevention and control of infectious *** combination of prevention-oriented epidemic prevention ideology and traditional medicine provides valuable insights,especially for impoverished and medically underserved regions.

关键词： infectious diseases Chinese medicine public health historical review

Evolution of High-energy Electron Distribution in Pulsar Wind Nebulae

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Research in Astronomy and Astrophysics 2024年第7期24卷 201-217页

作者： yi-Ming liu Hou-Dun Zeng Yu-Liang Xin Si-Ming liu yi Zhang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China School of Physical Science and Technology Southwest Jiaotong University

In this paper,we analyze the spectral energy distributions of 17 powerful (with a spin-down luminosity greater than1035erg s-1) young （with an age less than 15,000 yr） pulsar wind nebulae （PWNe） using a simple timein-dependent one-zone emission *** aim is to investigate correlations between model parameters and the ages of the corresponding PWNe,thereby revealing the evolution of high-energy electron distributions within *** findings are as follows:（1） The electron distributions in PWNe can be characterized by a double power-law with a super-exponential cutoff.（2） As PWNe evolve,the high-energy end of the electron distribution spectrum becomes harder with the index decreasing from approximately 3.5 to 2.5,while the low-energy end spectrum index remains constant near 1.5.（3） There is no apparent correlation between the break energy or cutoff energy and the age of PWNe.（4） The average magnetic field within PWNe decreases with age,leading to a positive correlation between the energy loss timescale of electrons at the break energy or the high-energy cutoff and the age of the PWN.（5） The total electron energy within PWNe remains constant near 2×1048erg,while the total magnetic energy decreases with age.

关键词： gamma-rays: general ISM: general ISM: supernova remnants radiation mechanisms: non-thermal

Revolution in thermoelectric cooling using PbSe thermoelectrics by grid plainification

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Science China Materials 2024年第5期67卷 1672-1673页

作者： Xiao-lei Shi Qingfeng liu Zhi-Gang Chen School of Chemistry and Physics ARC Research Hub in Zero-emission Power Generation for Carbon Neutralityand Centre for Materials ScienceQueensland University of TechnologyBrisbaneQueensland4000Australia State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

Thermoelectric materials and devices enable direct conversion between heat and electricity,holding potential applications in thermoelectric power generation,localized cooling,and electronic thermal management[1].Howev... 详细信息

关键词： enable thermoelectric constrained

Associative Tasks Computing Offloading Scheme in Internet of Medical Things with Deep Reinforcement Learning

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China Communications 2024年第4期21卷 38-52页

作者： Jiang Fan Qin Junwei liu lei Tian Hui School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The Internet of Medical Things(Io MT) is regarded as a critical technology for intelligent healthcare in the foreseeable 6G era. Nevertheless, due to the limited computing power capability of edge devices and task-related coupling relationships, Io MT faces unprecedented challenges. Considering the associative connections among tasks, this paper proposes a computing offloading policy for multiple-user devices(UDs) considering device-to-device(D2D) communication and a multi-access edge computing(MEC)technique under the scenario of Io MT. Specifically,to minimize the total delay and energy consumption concerning the requirement of Io MT, we first analyze and model the detailed local execution, MEC execution, D2D execution, and associated tasks offloading exchange model. Consequently, the associated tasks’ offloading scheme of multi-UDs is formulated as a mixed-integer nonconvex optimization problem. Considering the advantages of deep reinforcement learning(DRL) in processing tasks related to coupling relationships, a Double DQN based associative tasks computing offloading(DDATO) algorithm is then proposed to obtain the optimal solution, which can make the best offloading decision under the condition that tasks of UDs are associative. Furthermore, to reduce the complexity of the DDATO algorithm, the cacheaided procedure is intentionally introduced before the data training process. This avoids redundant offloading and computing procedures concerning tasks that previously have already been cached by other UDs. In addition, we use a dynamic ε-greedy strategy in the action selection section of the algorithm, thus preventing the algorithm from falling into a locally optimal solution. Simulation results demonstrate that compared with other existing methods for associative task models concerning different structures in the Io MT network, the proposed algorithm can lower the total cost more effectively and efficiently while also providing a tradeoff between delay and energy co

关键词： associative tasks cache-aided procedure double deep Q-network Internet of Medical Things(IoMT) multi-access edge computing(MEC)