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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han Zhu Xiong zhang Xiao-Qiang Li peng Li Yan-Bin Wang Shuang zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

Internal flow in sessile droplets induced by substrate oscillation:towards enhanced mixing and mass transfer in microfluidic systems

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Microsystems & Nanoengineering 2024年第3期10卷 369-379页

作者： Tianyi zhang peng Zhou Terrence Simon Tianhong Cui Department of Mechanical Engineering University of MinnesotaMinneapolisMN 55455USA

The introduction of flows within sessile droplets is highly effective for many lab-on-a-chip chemical and biomedical ***,generating such flows is difficult due to the typically small droplet ***,we present a simple,non-contact strategy to generate internal flows in sessile droplets for enhancing mixing and mass *** flows are driven by actuating a rigid substrate into oscillation with certain amplitude distributions without relying on the resonance of the droplet *** oscillation characteristics and corresponding flow patterns are documented *** indices and mass transfer coefficients of sessile droplets on the substrate surface are measured using optical and electrochemical *** demonstrate complete mixing within the droplets in 1.35 s and increases in mass transfer rates of more than seven times static *** of concept was conducted with experiments of silver nanoparticle synthesis and with heavy metal ion sensing employing the sessile droplet as a microreactor for synthesis and an electrochemical cell for *** degrees of enhancement of synthesis efficiency and detection sensitivity attributed to the internal flows are experimentally documented.

关键词： mixing oscillation synthesis

Underoil superhydrophilic flame-retardant 3D porous composite for efficient on-demand emulsion separation:Interface engineering design on sphagnum moss

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Friction 2024年第10期12卷 2222-2240页

作者： Yuyan GUO peng LIU Wenhao zhang Zhiguang GUO Weimin LIU Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei UniversityWuhan 430062China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

Oil pollution and the energy crisis make oil-water separation an urgent for human *** widespread use of materials with a single emulsion separation capability is *** on-demand separation materials can adapt to a wide range of application scenarios,thus having a wider range of *** underoil superhydrophilic surface is of great significance for realizing the on-demand separation of oil/water emulsions through the removal of water in the oil and oil in the water.A 3D porous emulsion separation material based on the superhydrophilic principle of sphagnum moss was *** material was prepared in a simple step by taking advantage of the adhesion of polydopamine and the introduction of the as-prepared superhydrophilic BaSO4 nanoparticles to achieve superhydrophilicity with a water contact angle(WCA)of 0°and an oil contact angle(OCA)of 157.3°,resulting in excellent separation performance for both water-in-oil and oil-in-water *** superhydrophilic porous composite(OSPC)can complete two kinds of emulsion separations by filtration or *** adsorbs water from water-in-oil emulsion to achieve separation,with a good adsorption capacity of 74.38 g/g and efficiency up to 99%.It can also filter oil-in-water emulsions with an efficiency of 99.92%.The separation efficiencies are all almost unchanged after ten separation ***,the material has excellent flame retardancy,which reduces the possibility of secondary *** three-dimensional porous sponge has excellent on-demand separation performance for multiple *** provides a new preparation strategy for underoil superhydrophilic materials and a new idea for the design direction of special wetting materials for the on-demand separation of oil/water emulsions.

关键词： on-demand emulsion separation porous absorption filtration underoil hydrophilicity superwettability

Genomic data and ecological niche modeling reveal an unusually slow rate of molecular evolution in the Cretaceous Eupteleaceae

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Science China(Life Sciences) 2024年第4期67卷 803-816页

作者： Kun-Li Xiang Sheng-Dan Wu Lian Lian Wen-Chuang He Dan peng Huan-Wen peng Xiao-Ni zhang hong-Lei Li Jia-Yu Xue hong-Yan Shan Gui-Xia Xu Yang Liu Zhi-Qiang Wu Wei Wang State Key Laboratory of Plant Diversity and Specialty Crops Institute of BotanyChinese Academy of SciencesBeijing 100093China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureKey Laboratory of Synthetic BiologyLaboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China China National Botanical Garden Beijing 100093China State Key Laboratory of Grassland Agro-Ecosystems and College of Ecology Lanzhou UniversityLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Landscape Architecture and Life Science/Institute of Special Plants Chongqing University of Arts and SciencesChongqing 402160China College of Horticulture Academy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjing 210095China Fairylake Botanical Garden Shenzhen&Chinese Academy of SciencesShenzhen 518004China

Living fossils are evidence of long-term sustained ecological ***,whether living fossils have little molecular changes remains poorly known,particularly in ***,we have introduced a novel method that integrates phylogenomic,comparative genomic,and ecological niche modeling analyses to investigate the rate of molecular evolution of Eupteleaceae,a Cretaceous relict angiosperm family endemic to East *** assembled a high-quality chromosome-level nuclear genome,and the chloroplast and mitochondrial genomes of a member of Eupteleaceae(Euptelea pleiosperma).Our results show that Eupteleaceae is most basal in Ranunculales,the earliest-diverging order in eudicots,and shares an ancient whole-genome duplication event with the other *** document that Eupteleaceae has the slowest rate of molecular changes in the observed *** unusually low rate of molecular evolution of Eupteleaceae across all three independent inherited genomes and genes within each of the three genomes is in association with its conserved genome architecture,ancestral woody habit,and conserved niche *** findings reveal the evolution and adaptation of living fossil plants through large-scale environmental change and also provide new insights into early eudicot diversification.

关键词： conservation genomics eudicots evolutionary rates niche conservatism phylogenomics

Multiwavelength Observations of the Infrared Dust Bubble N75 and its Surroundings

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Research in Astronomy and Astrophysics 2024年第4期24卷 262-270页

作者： Quan-Ling Cui Chuan-peng zhang Jun-Jie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar *** this work,we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C^(18)O,HCO^(+),HNC and N_(2)H^(+)observed by the 30 m IRAM *** also study the targets using data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,NRAO VLA Sky Survey and Bolocam Galactic Plane *** found that the C^(18)O emission is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to *** ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission,which may be excited by radiation from *** found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II with several class I cases distributed around N75,but no class II *** also found evidence of expanding feedback,which could have triggered star formation.

关键词： ISM:bubbles infrared:ISM galaxies:star formation

A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

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Science China Earth Sciences 2024年第3期67卷 751-768页

作者： Xueqin zhang Xiaoming XU Xiang LI peng CUI Du ZHENG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarifi

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan Mountains Region

A tectono-thermal perspective on the petroleum generation,accumulation and preservation in the southern Ordos Basin, North China

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Petroleum Science 2024年第3期21卷 1459-1473页

作者： peng Yang Zhan-Li Ren Jin-Hua Fu hong-Ping Bao Hui Xiao Zheng Shi Kun Wang Yuan-Yuan zhang Wen-Hui Liu Wen-Hou Li State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an710069ShanxiChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Exploration and Development Research Institute of PetroChina Changqing Oilfield CompanyXi'an710018ShaanxiChina Shaanxi Key Lab of Petroleum Accumulation Geology School of Earth Science and EngineeringXi'an Shiyou UniversityXian710065ShaanxiChina Wuxi Research Institute of Petroleum Geology Petroleum Exploration and Production Research InstituteSINOPECWuxi214126JiangsuChina

The southern Ordos Basin has excellent petroleum exploration ***,the tectono-thermal history and the controls on petroleum generation,accumulation and preservation conditions in southern basin are *** this study,we analyzed the present geothermal field,paleo-geothermal gradient,maturity of the hydrocarbon source rocks,uplift and cooling process and tectono-thermal evolution *** the study area,for the Ordovician,Permain and the Triassic strata,the present temperature is low(3070℃)in the southeastern area but high(80140℃)in the northwestern *** paleogeothermal gradient varied from 24℃/km to 30℃/km with a heat flow of 58—69 m W/m^(2)(i.e.,a medium-temperature basin).The paleo-temperatures are higher than the present temperatures and the maximum paleo-temperatures controlled the thermal maturity of the source *** vitrinite reflectance(Ro)values of the Triassic strata are>0.7%and the thermal maturity reached the middlemature oil generation *** Rovalues of the Permian-Ordovician strata are>1.8%and the thermal maturity reached the over-mature gas generation *** southern Ordos Basin has experienced the multiple tectonic events at the Late Ordovician Caledonian(452 Ma),Late Triassic(215 Ma),Late Jurassic(165160 Ma),End-Early Cretaceous(110100 Ma)and Cenozoic(since 40 Ma).A large-scale tectonothermal event occurred at the End-Early Cretaceous(110100 Ma),which was controlled by lithospheric extension,destruction and *** event led to the highest paleo-temperatures and thermal maturities and coeval with the peak period of petroleum generation and *** southern Ordos Basin has undergone rapid and large-scale uplift since the Late Cretaceous due to expansion of the northeastern margin of the Tibetan Plateau,uplift of the Qinling orogenic belt and thrust faulting in the Liupanshan tectonic *** southern Ordos Basin experienced tectonic overprinting that was strong in the south and weak in the *** str

关键词： Fission-track dating Vitrinitereflectance Geothermal field Tectono-thermal evolution Petroleum geology Ordos Basin

Acoustic carrier signal transmission technology and its potential for in-site monitoring of sliding electrical contact used in gas-insulated switchgear/gas-insulated transmission line

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High Voltage 2024年第2期9卷 287-295页

作者： Chen Chen Yutong zhang Huijun Zhao Zongren peng Qingyu Wang Xi'an Jiaotong University Xi'anChina

A wireless signal transmission technology based on acoustic carrier is proposed,which overcomes the limitation of electromagnetic signal shielding and shows great potential for in-site monitoring of sliding electrical contact used in gas-insulated switchgear(GIS)/gasinsulated transmission line(GIL).Here,the state parameter of the sliding electrical contact is modulated onto the frequency domain of an ultrasound *** a mechanical wave,the ultrasonic wave is immune to electromagnetic shielding,so that it could carry the sensing signal to penetrate the metal shielding layer and transmit to the external terminals of GIS/*** principle and signal modulation process of the acoustic carrier based transmission system have been demonstrated in *** simulation and experiment have been conducted to analyse the system characteristics as well as optimise the system *** a proof-of-concept application,the in situ and on-line monitoring of the thermal rise of a slide electrical contact both in a current loading equivalent model and a prototype of GIS is *** results fit well with the physical process,and show a good measurement accuracy of 0.6%and tem-perature sensitivity of 400 Hz/℃.

关键词： electrical potential Acoustic

Guanine-derived F,N co-doped carbon-shell encapsulated iron carbide nanoparticles for enhanced CO_(2)electroreduction activity

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Nano Research 2024年第6期17卷 4744-4752页

作者： Shuo Chen Lishun Pei Ying peng Xuefei zhang Zailai Xie Key Laboratory of Advanced Carbon-Based Functional Materials(Fujian Province University) Fuzhou UniversityFuzhou 350016China

The development of highly selective,cost-effective,and energy-efficient electrocatalysts is critical for carbon dioxide reduction reaction(CO_(2)RR)to produce high-value ***,we propose a facile strategy to obtain F,N co-doped carbon-coated iron carbide(Fe3C)nanoparticles by using biomolecule guanine and hexadecafluorophthalocyanine iron as raw ***,this method involves only one-step pyrolysis and does not require any guiding agent or sacrificial *** from the advantageous surface microenvironment adjustments achieved through graphitic N(GN)and F co-doping,Fe3C@NF-G-1000 demonstrates exceptional efficacy in the electroreduction of CO_(2)to carbon monoxide(CO)with an impressive Faradic efficiency(FEco)up to 98%at the potential of−0.55 V(*** hydrogen electrode(RHE)).Furthermore,it delivers a remarkable current density of up to−43 mA·cm^(−2)and exhibits virtually no current attenuation over a span of 20 h within the flow *** from density functional theory(DFT)calculations reveal that the composite structure of GN and F co-doped graphitic layer and Fe3C exhibits different electron density distributions from that of iron carbide *** is attributed to the synergistic effect of the composite structure leading to the enrichment of electrons in the graphite layer on the surface,which contributes to the stability of the key reaction intermediate*COOH,thus,resulting in an enhanced catalytic activity and ***,this work introduces a new and promising approach to the design of green and low-cost carbon-coated metal materials for CO_(2)reduction reactions.

关键词： guanine F,N co-doped carbon dioxide reduction reaction(CO_(2)RR) Fe-based catalyst

Research on dynamic measurement method of speckle in laser display

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Optoelectronics Letters 2024年第6期20卷 360-366页

作者： LIU hong LIU Yaning zhang Xiaoyu School of Electronics Information Shanghai Dianji UniversityShanghai 201306China

Laser display technology is the most promising display technology in the market and is widely used in many fields. However, laser speckle has been troubling the application and expansion of this technology in some fields. In order to better evaluate the speckle, speckle measurement methods must be studied. In this study, a dynamic measurement method for laser speckles is proposed according to the optical superposition characteristics of speckle, which can reduce the influence of non-coherent factors on the speckle measurement results. The feasibility of the dynamic speckle measurement method is verified by designing an experimental scheme.

关键词： Research on dynamic measurement method of speckle in laser display