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Systematic study of the synthesis of heavy and superheavy nuclei in 48Ca-induced fusion-evaporation reactions

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Nuclear Science and Techniques 2024年第7期35卷 157-172页

作者： Shi-Hao Zhu tian-liang Zhao Xiao-Jun Bao Department of Physics Collaborative Innovation Center for Quantum EffectsKey Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationHunan Normal UniversityChangsha410081China School of Nuclear Science and Technology Lanzhou UniversityLanzhou730000China School of Physics Xi’an Jiaotong UniversityXi’an710049China

We systematically studied the evaporation residue cross sections of ^(48)Ca-induced reactions on lanthanide and actinide target nuclei under the Dinuclear System(DNS)model framework to check the reliability and applicability of the *** produce new proton-rich Fl and Lv isotopes through hot fusion reactions in the superheavy element region with Z≥104,we utilized the reactions ^(48)Ca+^(236,238,239) Pu and ^(48)Ca+^(242,243,244,250) ***,owing to the detection limit of available equipment(0.1 pb),only 283Fl and 287−289Lv,which have the maximum evaporation residue cross section values of 0.149,0.130,9.522,and 0.309 pb,respectively,can be ***,to produce neutron-deficient isotopes of actinides near the proton drip line with Z=93−100,we attempted to generate the new isotopes(224−227Pu,228−232,237Cm)using the reactions ^(48)Ca+180,182,183 W and ^(48)Ca+^(184,186,187,192) *** maximum evaporation residue cross section values are 0.07,0.06,0.26,and 0.30 nb for the former set of reactions,and 1.96 pb,5.73 pb,12.16 pb,19.39 pb,54.79 pb,and 6.45 nb for the latter,*** results are expected to provide new information for the future synthesis of unknown neutron-deficient isotopes.

关键词： Dinuclear system(DNS)model Evaporation residue cross section Neutron-deficient isotopes

Global convergence in terrestrial gross primary production response to atmospheric vapor pressure deficit

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Science China(Life Sciences) 2024年第9期67卷 2016-2025页

作者： Chao Huang Jingfeng Huang Jingfeng Xiao Xing Li Hong SHe yu liang Fusheng Chen Hanqin tian Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang 330045China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Institute of Applied Remote Sensing&Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Key Laboratory of Agricultural Remote Sensing and Information Systems Zhejiang ProvinceZhejiang UniversityHangzhou 310058China Earth Systems Research Center Institute for the Study of EarthOceansand SpaceUniversity of New HampshireDurham NH 03824USA Research Institute of Agriculture and Life Sciences Seoul National UniversitySeoul 08826South Korea School of Natural Resources University of Missouri203 ABNR BuildingColumbiaMO 65211USA Schiller Institute for Integrated Science and Society Department of Earth and Environmental SciencesBoston CollegeChestnut HillMA 02467USA

Atmospheric vapor pressure deficit(VPD)increases with climate warming and may limit plant ***,gross primary production(GPP)responses to VPD remain a mystery,offering a significant source of uncertainty in the estimation of global terrestrial ecosystems carbon *** this study,in-situ measurements,satellite-derived data,and Earth System Models(ESMs)simulations were analysed to show that the GPP of most ecosystems has a similar threshold in response to VPD:first increasing and then *** VPD exceeds these thresholds,atmospheric drought stress reduces soil moisture and stomatal conductance,thereby decreasing the productivity of terrestrial *** ESMs underscore CO_(2) fertilization effects but predict significant GPP decline in low-latitude ecosystems when VPD exceeds the *** results emphasize the impacts of climate warming on VPD and propose limitations to future ecosystems productivity caused by increased atmospheric water *** VPD,soil moisture,and canopy conductance interactions into ESMs enhances the prediction of terrestrial ecosystem responses to climate change.

关键词： atmospheric water demands soil moisture stomatal conductance photosynthesis climate warming

Electronic-scale assessment of high-temperature oxidation mechanisms in a novel Fe-based alloy

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Journal of Iron and Steel Research International 2024年第4期31卷 982-997页

作者： Wei-di Luo Ting-ping Hou Xuan liang Dong Zhang Heng-fu Lin yu Li tian-liang Zhao Cheng-yang Hu Serhii Yershov Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy.Wuhan University of Science and Technology.Wuhan 430081 HubeiChina Hubei Province Key Laboratory of Systems Science in Meallurgial Process Wuhan University of Science and Technology.Wuhan 430081.Hubei.China International Research Institute for Steel Technology Wuhan University of Science and Technology.Wuhan 430081.HubeiChina Collaborative Innovation Center for Advanced Steels w uhan University of Science and Technology.Wuhan 430081.HuleiChina

The development of alloys with high antioxidation performance is limited by the ambiguous details of the oxidation ***,based on the structures of internal oxides detected by high-resolution transmission electron microscopy,a hybrid method combining first-principles calculation,climb image nudged elastic band method and quasi-harmonic Debye model has been implemented to explain the oxidation mechanism with an emphasis on the origin of delamination and *** results showed that the delamination of oxides corresponds to the acceleration of diffusion of Cr element caused by lamellar *** reduction in the cracking occurrence at high temperature mainly results from the smaller bulk modulus of ***,the stronger chemical bonds promoted by lamellar structures also correspond to the higher crackingresistance.

关键词： Oxidation Crystal structure Diffusion Cracking-First-principles calculation

Intelligent reflecting surfaces-assisted millimeter wave communication:Channel estimation based on deep learning

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 49-56页

作者： Kang Xiaofei Wang tian liang Xian College of Communication and Information Engineering Xi'an University of Science and TechnologyXi'an 710600China

In response to the challenge posed by the complexity of the system and the difficulty in obtaining accurate channel state information(CSI)for millimeter wave communication assisted by intelligent reflecting surfaces(IRS),we propose a deep learning-based channel estimation *** proposed scheme employs a hybrid active/passive IRS architecture,wherein the least square(LS)algorithm is initially utilized to acquire the channel estimate from the active ***,this estimation is interpolated to obtain a preliminary channel estimation and ultimately refined into an accurate estimate of the channel using the channel super-resolution convolutional neural network(Chan-SRCNN)deep learning *** simulation results demonstrate that the proposed scheme surpasses LS,orthogonal matching pursuit(OMP),synchronous OMP(SOMP),and deep neural network(DNN)channel estimation algorithms in terms of normalized mean squared error(NMSE)performance,thereby validating the feasibility of the proposed approach.

关键词： intelligent reflecting surface millimeter wave channel estimation deep learning

基于VEGF/PI3K/Akt通路基因表达探讨骨坏死康复丸对激素性股骨头坏死大鼠血管新生的影响

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广州中医药大学学报 2024年第8期41卷 2127-2135页

作者：李文茜田亮玉张谨沈彩红杨志敏冯小艳郭家巧曹玉举郑州中医骨伤病医院河南郑州450016 河南省骨坏死研究中医药重点实验室河南郑州450016 河南省骨伤病中医诊疗工程技术研究中心河南郑州450016

【目的】观察骨坏死康复丸对激素性股骨头坏死(SONFH)大鼠的治疗作用及机制。【方法】将60只大鼠随机分为空白组,模型组,仙灵骨葆胶囊组及骨坏死康复丸低、中、高剂量组,每组10只。除空白组,其他各组大鼠采用脂多糖联合糖皮质激素诱导... 详细信息

【目的】观察骨坏死康复丸对激素性股骨头坏死(SONFH)大鼠的治疗作用及机制。【方法】将60只大鼠随机分为空白组,模型组,仙灵骨葆胶囊组及骨坏死康复丸低、中、高剂量组,每组10只。除空白组,其他各组大鼠采用脂多糖联合糖皮质激素诱导法建立SONFH模型。干预结束后,分别进行股骨头的血管造影观察骨髓内微血管变化、苏木素-伊红(HE)染色并计算空骨陷窝率、Micro-CT扫描分析、压缩实验,采用实时定量聚合酶链反应(RT-qPCR)法检测全血磷脂酰肌醇3-激酶(PI3K)、蛋白激酶B(Akt)1、血管内皮生长因子(VEGF)、血小板内皮细胞黏附分子1(CD31)基因表达。【结果】与空白组比较,模型组股骨头髓腔内血供差,空骨陷窝率增加(P0.05)。【结论】骨坏死康复丸可改善大鼠激素性股骨头坏死,其机制与促进VEGF/PI3K/Akt通路基因表达,进而促进血管新生有关。

关键词：骨坏死康复丸激素性股骨头坏死血管新生磷脂酰肌醇3-激酶(PI3K) 蛋白激酶B(Akt)1 血管内皮生长因子(VEGF) 血小板内皮细胞黏附分子1(CD31) 大鼠

In memoriam:Shizhu Wen(1932-2023)

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Friction 2024年第7期12卷 1341-1346页

作者： Jianbin LUO Yonggang MENG yu tian State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Professor Shizhu Wen,the winner of the 2015 Tribology Gold Medal,passed away due to illness on November 3,2023,at the age of *** was a professor of Tsinghua University,an academician of the Chinese Academy of Sciences,and the Honorary President of the Chinese Tribology Institute(CTI)from 1997 to *** Wen was born in 1932 in Jiangxi Province of China and graduated from Tsinghua University in 1955,where he was awarded the Outstanding Graduate Gold Medal and then remained as an assistant professor at the *** Wen was promoted to full professor in *** had undertaken tribology research at the Imperial College London in 1979 and *** 1985,he presided over the establishment of the State Key Laboratory of Tribology(SKLT)of Tsinghua University and served as the first director of the SKLT.

关键词： sided professor zhu

Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers

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Petroleum Science 2024年第1期21卷 430-444页

作者： yu-Ning Yong Zhao-Quan Guo Shou-Ceng tian Lu-Yao Ma tian-yu Wang Mao Sheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Beijing Petroleum Machinery Company Limited CNPC Engineering Technology R&D Company LimitedBeijing102206China Smart Energy Co. LtdChina Xiongan GroupXiong’an New Area071000HebeiChina

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas *** paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing *** crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are *** results show that radial borehole fracturing in multiple layers generates diverse fracture *** types of fractures are identified based on the connectivity between hydraulic fractures and radial *** vertical distance significantly influences fracture propagation perpendicular to the radial borehole *** increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole *** azimuth also influences fracture propagation along the radial borehole *** the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress *** breakdown pressure correlates with diverse fracture geometries *** the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown *** the azimuth and increasing the diameter also decrease the breakdown *** extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown *** research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and g

关键词： Multi-layer radial boreholes Hydraulic fracturing Fracture propagation Pressure characteristic

Photoinduced superlubricity on TiO_(2) surfaces

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Friction 2024年第3期12卷 428-438页

作者： Ke HAN Liran MA yu tian Jianbin LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Received:16 September 2022/Revised:28 October 2022/Accepted:27 December 2022The author(s)2022.

Superlubricity control is of great interest in both industry and scientific research,and several methods have been proposed to achieve this *** this work,ultraviolet(UV)light was introduced into titanium dioxide(TiO_(2))and silicon nitride(Si_(3)N_(4))tribosystems to accomplish photoinduced *** friction coefficients(COFs)between Si_(3)N_(4) balls and TiO_(2) plates in the mixtures of sulfuric acid(H^(2)SO_(4))solution and glycerol solution were obviously reduced,and the system entered the superlubricity region(COF<0.01)after UV illumination at a speed of 56 mm/***,the COF was much larger without UV treatment than that with UV *** formation of silica(SiO_(2))layers on the surfaces of Si_(3)N_(4) balls and the elastohydrodynamic effects were determined to be fundamental to the low friction in this experiment,and the enhancement of the combination between the TiO_(2) surface and the hydroxy group of glycerol by UV illumination was the key to the photoinduced superlubricity in this *** findings showed one method for achieving superlubricity by introducing a light field that could be further applied to special working conditions.

关键词： light control friction superlubricity glycerol titanium dioxide(TiO_(2))

Heat Transfer Characteristics of a Microchannel Heat Sink with Highly-Dense Micro-Jet Arrays

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Journal of Thermal Science 2024年第3期33卷 1148-1160页

作者： ZHANG yu CHEN Xiaoyan MIAO Lin CHEN liang HOU yu State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China Beijing Aerospace Technology Institute Beijing100083China

This paper proposed a new structure of highly-dense micro-jet arrays for hybrid jet-impingement/microchannel heat sinks(~120 jet per cm^(2) with jet width of 0.35 mm).Parametric study is performed to investigate the influence of structure and flow parameters on the convective heat transfer of water jet cooling in confined *** simulation results show that the optimal jet width,jet spacing and impingement distance are around 0.2 mm,0.2 mm and 0.3 mm,respectively,which can achieve a low thermal resistance as well as a relatively low pressure *** analysis of the heat transfer pathways shows that the micro-fin jet structures can extend the impinging heat transfer area and conduct a considerable proportion of heat,which can reach up to 38.9%with the Reynolds number ranging from 797.1 to *** heat transfer characteristics in the heat sink will shift from impingement dominated heat transfer to the channel-convection dominated heat transfer as the jet impingement distance increases.A correlation is proposed to predict the average Nusselt number on the stagnation area for the heat sink with different structure parameters,and the deviations of predictions from the numerical results are less than 10%.

关键词： hybrid heat sink impingement microchannel thermal management high heat flux