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High Voltage 2024年第2期9卷 410-418页

作者： Haitian Wang Yi Luo Mingyu Zhou Xintong ren George Chen GEIRI BerlinGermany The Tony Davies High Voltage Laboratory University of SouthamptonSouthamptonUK

The potential of using eco-friendly thermoplastic polypropylene(PP)-based insulation for high voltage direct current(HVDC)cable has been widely investigated but much less work on the PP-based semiconducting screen(sc).Considering a long service life(>30 years)under high temperature and high electrical stress is required for typical HVDC cables,and investigations on the effect of antioxidant(AO)concentration and thermal oxidative sta-bility,mechanical,and electrical properties of PP-based scs have been *** has been demonstrated that an appropriate combination and amounts of AOs are critical for achieving high thermal stability and maintaining the mechanical properties of sc after ageing in a harsh environment(150°C,with Cu,in air,7 days).Although higher amounts of space charges have been observed in sc/PP/sc samples with higher AO concentrations,the impact on space charge behaviours is less after ageing,suggesting that ageing(or operating at high temperature)leads to microstructure evolution in sc and can potentially mitigate space accumulation in PP-based insulating materials.

关键词： microstructure thermal high

A highly sensitive fluorescent HClO probe for discrimination between cancerous and normal cells/tissues

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Chinese Chemical Letters 2024年第6期35卷 417-420页

作者： Linfang Wang Jing Liu Minghao ren Wei Guo Department of Chemistry Changzhi UniversityChangzhi 046011China school of Chemistry and Chemical engineering Shanxi UniversityTaiyuan 030006China

Elevated level of hypochlorous acid(HClO)is closely associated with cancer *** HClO level in cancer cells would provide important evidence in either early-stage cancer diagnostics or monitoring of its treatment *** this work,a new pyronine-based fluorescent probe for rapid and sensitive detection of HClO was developed by condensing meso-formyl pyronine(PyCHO)with 2-hydrazinopyridine to form meso-pyridylhydrazone-functionalized pyronine PyHP,PyHP is nonfluorescent due to the excited-state C=n isomerization nonradiative decay,whereas the HClO-triggered formation of meso-triazolopyridyl pyronine PyTP abolishes the C=n isomerization and thus greatly enhances the *** the probe,the cancer cells/tumor were distinguished with high-contrast from normal ones by laser confocal fluorescence imaging,and the tumor-to-normal(T/n)ratios obtained exceed the clinically acceptable threshold of ***,its capability of in vivo imaging tumor was also *** results indicate the potential of PyHP as an effective tool in the early clinical diagnosis of cancers.

关键词： Meso-pyridylhydrazone-functionalized pyronine Meso-substituents Tumor-to-normal(T/n)ratios Fluorescent probes Hypochlorous acid

Exceptional mechanical performance and macroscale superlubricity enabled by core-shell-like MoS_(2)/B_(4)C film

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science China(Technological sciences) 2024年第7期67卷 2018-2030页

作者： ren SiMing GAO ZhenRong FAn Xin WAnG HaiXin WAnG LiPing Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

Molybdenum disulfide(MoS_(2)) films are widely deployed in industrial applications owing to their inherent interlayer slip characteristics, offering energy consumption savings and prolonged mechanical part performance. nevertheless, their practical utility is limited by environmental constraints and the limitations of preparation techniques, which hinder the attainment of robust superlubricity(friction coefficient n, through magnetron sputtering technology, we synthesize a core-shell-like nanocomposite composed of MoS_(2)nanosheets encapsulating B_(4)C. The core-shell-like structure enables the resulting films to preferentially grow crystalline MoS_(2), providing them with outstanding mechanical properties and efficient lubrication over a wide range of temperatures. Remarkably, such film achieves robust macroscale superlubricity and an ultralow wear rate(1.7 ×10^(-8)mm^(3)n-1m^(-1)) under high contact stress in a mild vacuum environment. This noteworthy outcome is primarily attributable to the self-segmentation of the macroscale contact interface during the friction process, involving:(1) a large amount of wear debris is embedded into the wear track to create extensive micro-sized asperities;(2) a nanolayer of amorphous carbon enriched with oxide nanoparticles is formed on the uppermost part of these asperities;(3) numerous incommensurate nanocontacts comprising nanoparticles and highly oriented MoS_(2)nanosheets are established, culminating in the achievement of robust superlubricity. Our pioneering design, coupled with the elucidation of the underlying superlubricity mechanism, holds significant promise for advancing the development of robust and high-performance lubricants.

关键词： MoS_(2)/B_(4)C nanocomposites core-shell-like structure H/E ratio high-temperature friction macroscale superlubricity

Investigating the elliptic anisotropy of identified particles in p-Pb collisions with a multi-phase transport model

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nuclear science and Techniques 2024年第2期35卷 160-169页

作者： Si-Yu Tang Liang Zheng Xiao-Ming Zhang ren-Zhuo Wan school of Mathematical and Physical sciences Wuhan Textile UniversityWuhan 430200China school of Mathematics and Physics China University of Geosciences(Wuhan)Wuhan 430074China Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China Hubei Key Laboratory of Digital Textile Equipment Wuhan Textile UniversityWuhan 430200China school of Electronic and Electrical engineering Wuhan Textile UniversityWuhan 430200China

The elliptic azimuthal anisotropy coefficient(v_(2))of the identified particles at midrapidity(|η|<0.8)was investigated in p-Pb collisions at√s_(nn)=5.02 TeV using a multi-phase transport model(AMPT).The calculatio... 详细信息

The elliptic azimuthal anisotropy coefficient(v_(2))of the identified particles at midrapidity(|η|nvestigated in p-Pb collisions at√s_(nn)=5.02 TeV using a multi-phase transport model(AMPT).The calculations of differential v_(2)based on the advanced flow extraction method of light flavor hadrons(pions,kaons,protons,andΛ)in small collision systems were extended to a wider transverse momentum(p_(T))range of up to 8 GeV/c for the first *** string-melting version of the AMPT model provides a good description of the measured p_(T)-differential v_(2)of the mesons but exhibits a slight deviation from the baryon v_(2).In addition,we observed the features of mass ordering at low p_(T)and the approximate number-of-constituentquark(nCQ)scaling at intermediate p_(T).Moreover,we demonstrate that hadronic rescattering does not have a significant impact on v_(2)in p-Pb collisions for different centrality selections,whereas partonic scattering dominates in generating the elliptic anisotropy of the final *** study provides further insight into the origin of collective-like behavior in small collision systems and has referential value for future measurements of azimuthal anisotropy.

关键词： Azimuthal anisotropy Small collision systems Transport model

Characteristics and Preliminary Causes of Tropical Cyclone Remote Precipitation over China

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Journal of Ocean University of China 2024年第4期23卷 845-858页

作者： JIA Li ren Fumin MCBRIDE John Leonard COnG Chunhua school of Atmospheric science Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China school of Earth science University of MelbourneMelbourne 3052Australia Research and Development Division Bureau of MeteorologyMelbourne 3052Australia Shandong Meteorological Bureau Jinan 250031China

In this study,the characteristics and preliminary causes of tropical cyclone remote precipitation(TRP)over China during the period from 1979 to 2020 are *** indicated that approximately 72.42%of tropical cyclones(TCs)in the Western Pacific produce TRP over *** peak months for TRP are July and *** four key regions of TRP are the adjacent areas between the Sichuan and Shaanxi Provinces,the northern coast of the Bohai Sea,the coast of the Yellow Sea,and the southern coast *** typical distance between the station with TRP and the TC center ranges from 1500 to 2500 *** of these stations are situated north to 60°west of north of the *** south–west water vapor transportation on the west side of the TC is crucial to *** has a decreasing trend because of the decrease in the number of TCs that generate *** the perspective of large-scale environmental conditions,a decrease in the integrated horizontal water vapor transport in China' Mainland,the weakening of upward motion at approximately 25°–35°n,which is inconducive to convection,and an increase in low-level vertical wind shear,which is unfavorable for the development of TC in areas with high frequencies of TRP-related TCs,are the factors that result in the decreasing trend of TRP.

关键词： tropical cyclone remote precipitation characteristics causes

Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips

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Defence Technology（防务技术） 2024年第2期32卷 309-316页

作者： Jie ren Yunfeng Li Mingyu Li Xingyu Wu Jiabao Wang Qingxuan Zeng State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing 100081China

Copper-based azide(Cu(n_(3))2 or Cun_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent ***,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA *** aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition *** this work,Cu(n_(3))2 and Cun_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring n_(3)-concentration through *** spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test *** optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content *** with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory ***,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was *** study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems.

关键词： Copper-based azide chips Spectrophotometry Separation method Quantitative analysis Ignition ability

Global patterns of soil phosphatase responses to nitrogen and phosphorus fertilization

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Pedosphere 2024年第1期34卷 200-210页

作者： Xiaomei GOU Yongqing ren Xin QIn Xiaorong WEI Jingjing WAnG State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau the Research Center of Soil and Water Conservation and Ecological EnvironmentChinese Academy of Sciences and Ministry of EducationYangling 712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China River and Lake Management Office Shaanxi Provincial Department of Water ResourcesXi'an 710004China College of natural Resources and environment Northwest A&F UniversityYangling 712100China University of Chinese Academy of sciences Beijing 100049China CAS Center for Excellence in Quaternary science and Global Change Xi'an 710061China

Hydrolysis of organic phosphorus(P) by soil phosphatases is an important process of P cycling in terrestrial ecosystems, significantly affected by nitrogen(n) and/or P fertilization. However, how soil acid phosphatase(ACP) and alkaline phosphatase(ALP) activities respond to n and/or P fertilization and how these responses vary with climatic regions, ecosystem types, and fertilization management remain unclear. This knowledge gap hinders our ability to assess P cycling and availability from a global perspective. We performed a meta-analysis to evaluate the global patterns of soil ACP and ALP activities in response to n and/or P addition. We also examined how climatic regions(arctic to tropical), ecosystem types(cropland, grassland, and forest), and fertilization management(experiment duration and fertilizer type and application rate) affected changes in soil phosphatases after fertilization. It was shown that n fertilizer resulted in 10.1% ± 2.9% increase in soil ACP activity but a minimal effect on soil ALP activity. In contrast, P fertilizer resulted in 7.7% ± 2.6% decrease in soil ACP activity but a small increase in soil ALP activity. The responses of soil ACP and ALP activities to n and/or P fertilization were largely consistent across climatic regions but varied with ecosystem types and fertilization management, and the effects of ecosystem types and fertilization management were enzyme-dependent. Random forest analysis identified climate(mean annual precipitation and temperature) and change in soil pH as the key factors explaining variations in soil ACP and ALP activities. Therefore, n input and ecosystem types should be explicitly disentangled when assessing terrestrial P cycling.

关键词： acid phosphatase alkaline phosphatase ecosystem type fertilization management meta-analysis phosphorus cycling phosphorus limitation

Reactive molecular dynamics insight into the thermal decomposition mechanism of 2,6-Bis(picrylamino)-3,5-dinitropyridine

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Defence Technology（防务技术） 2024年第3期33卷 134-146页

作者： Jianbo Fu Hui ren Xinzhou Wu Yongjin Chen Mi Zhang Yazhi Cheng State Key Laboratory of Explosion science and Technology Beijing Institute of TechnologyBeijing 100081China

2,6-bis(picrylamino)-3,5-dinitropyridine(PYX)has excellent thermostability,which makes its thermal decomposition mechanism receive much *** this paper,the mechanism of PYX thermal decomposition was investigated thoroughly by the ReaxFF-lg force field combined with DFT-B3LYP(6-311++G)*** detailed decomposition mechanism,small-molecule product evolution,and cluster evolution of PYX were mainly *** the initial stage of decomposition,the intramolecular hydrogen transfer reaction and the formation of dimerized clusters are earlier than the denitration *** the progress of the reaction,one side of the bitter amino group is removed from the pyridine ring,and then the pyridine ring is *** final products produced in the thermal decomposition process are CO_(2),H_(2)O,n_(2),and H_(2).Among them,H_(2)O has the earliest generation time,and the reaction rate constant(k_(3))is the *** clusters are formed during the decomposition of PYX,and the formation,aggregation,and decomposition of these clusters are strongly affected by *** low temperatures(2500 K-2750 K),many clusters are *** high temperatures(2750 K-3250 K),the clusters aggregate to form larger *** 3500 K,the large clusters decompose and become *** the late stage of the reaction,H and n in the clusters escaped almost entirely,but more O was trapped in the clusters,which affected the auto-oxidation process of ***'s initial decomposition activation energy(E_(a))was calculated to be 126.58 kJ/*** work contributes to a theoretical understanding of PYX's entire thermal decomposition process.

关键词： PYX Thermal decomposition ReaxFF-lg MD simulations Excellent thermostable explosives

Synthesis of poly(thiourethane-alt-thioester)by alternating ring-opening copolymerization of n-thiocarboxyanhydrides and episulfides

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science China Chemistry 2024年第9期67卷 3091-3097页

作者： Wei Xiong Tianjun Yue Haiwang Lai Chunyan Lyu Weimin ren Hua Lu Beijing national Laboratory for Molecular sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116081China

Polythiourethanes(PTU)and polythioesters(PTE)derived from renewable sources are emerging sustainable polymers for their excellent degradability and ***,P(TU-alt-TE)copolymers have been rare and challenging to ***,we report the efficient synthesis of novel P(TU-alt-TE)copolymers via the alternating copolymerization of n-thiocarboxyanhydrides(nTA)/episufides(ES)and provide mechanistic insight into the alternating chain propagation process via density functional theory(DFT)*** incorporation of ESs into traditional peptide backbone is capable of adjusting the glass transition temperature below thermal decomposition temperature,which confers better thermal processability by regulating the rigidity of the backbone and the hydrogen bond interaction among the polymer *** PTUs with tailored properties are accessible by altering the feeding ratio of nTAs and(bifunctional)***,the thiourethane in the backbone can endow interesting underwater adhesion properties to the *** the broad scope of nTA and ES monomers,this method is expected to provide a promising and general route to a wide range of P(TU-alt-TE)copolymers with diverse properties.

关键词： poly(thiourethane-alt-thioester) alternating ring-opening copolymerization n-thiocarboxyanhydrides episulfides

High-precision modeling of tide-induced 3-D magnetic field and analysis of geomagnetic satellite orbit requirements

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science China Earth sciences 2024年第1期67卷 165-178页

作者： Zhengyong ren Cong YAnG Hongbo YAO Xu TAnG Jingtian TAnG Keke ZHAnG Key Laboratory of Metallogenic Prediction of nonferrous Metals and Geological environment Monitoring Ministry of Education Central South UniversityChangsha 410083China Hunan Key Laboratory of nonferrous Resources and Geological Hazards Exploration Changsha 410083China school of Geosciences and Info-Physics Central South UniversityChangsha 410083China State Key Laboratory of Lunar and Planetary sciences Macao University of Science and TechnologyMacao 999078China

Ground-based magnetic observatories and geomagnetic satellites can observe the induced magnetic field generated by the motion of seawater containing sodium and chlorine *** the three-dimensional(3-D)spatial distribution of tide-induced magnetic fields(TIMF)is crucial for inverting the electrical conductivity structure of the oceanic *** also serves as an essential basis for designing optimal geomagnetic observatories and satellite ***,existing methods for simulating TIMF suffer from limitations in inaccurately modeling realistic coastlines,heterogeneous land and sea surface properties,and complex deep Earth structures,thereby the interpretational level of TIMF data is *** overcome this issue,we developed a tetrahedral-based finite element method for simulating TIMF,which can efficiently approximate realistic coastlines,heterogeneous land and sea surface properties,and complex deep Earth ***,we derived the boundary value problem for the seawater motion-induced electromagnetic field,which was solved using the vector finite element method based on tetrahedral ***,using the latest ocean depth and seafloor sediment layer models,we constructed a 3-D conductivity model of the Earth,which includes realistic coastlines,heterogeneous land and sea conductivity *** then computed the TIMF using the M_(2)tidal source as an example and validated our method by comparing it with results obtained from spherical harmonic finite element and integral equation ***,utilizing the computed high-precision M_(2),n_(2),and O1 TIMF signals,we marked global observatories capable of observing strong M_(2),n_(2),and O1 TIMF signals and predicted alternative stations suitable for tide signal ***,we calculated TIMF at heights of 450 and 200 km for the Macao science Satellite 1 and its subsequent *** results indicate that the amplitude of the tidal-induced magnetic field at

关键词： Ocean motional induction Electromagnetic induction Ocean tides Geomagnetic satellite Macao science Satellite 1