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Origin of the near-room temperature resistance transition in lutetium with H2/N2 gas mixture under high pressure

National Science Review 2024年第7期11卷 26-32页

作者： Di Peng Qiaoshi Zeng Fujun Lan Zhenfang xing Zhidan Zeng Xiaoxing ke Yang Ding Ho-kwang mao key Laboratory of materials Physics Institute of Solid State Physics Hefei Institutes of Physical Science(HFIPS)Chinese Academy of Sciences Science Island Branch Graduate School of University of Science and Technology of China Center for High Pressure Science and Technology Advanced Research Shanghai key Laboratory of material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS) State key Laboratory of Superhard materials Institute of PhysicsJilin University College of materials Science&Engineering Beijing University of Technology

The recent report of room-temperature superconductivity at near-ambient pressure in nitrogen-doped lutetium hydride（Lu-H-N） by Dasenbrock-Gammon et al. [Nature 615, 244–250（2023）] has attracted tremendous attention due to its anticipated great impact on technology. However, the results could not be independently reproduced by other groups worldwide in follow-up studies, which elicited intense controversy. Here, we develop a reliable experimental protocol to minimize the extensively concerned extrinsic influences on the sample by starting the reaction from pure lutetium loaded with an H2/N2gas mixture in a diamond anvil cell under different pressures and temperatures and simultaneously monitoring the entire chemical reaction process using in situ four-probe resistance measurements. Therefore, we could repeatedly reproduce the near-room temperature upsurge of electrical resistance at a relatively early stage of the chemical reaction. However, the mechanism is suggested to be a metal-to-semiconductor/insulator transition associated with the structural modulation in the non-stoichiometric Lu-H-N, rather than superconductivity.

关键词： superconductivity high pressure lutetium hydride resistance transition metal-to-semiconductor/insulator transition

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A Detailed Thermal Resistance Network Analysis of FCBGA Package

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Journal of Thermal Science 2024年第1期33卷 18-28页

作者： DANG Hao LU Yang DU Yanzheng ZHANG Xiu ZHANG Qian ma Weigang ZHANG xing key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Zhongxing Telecom Equipment Corporation Shanghai 201203China

Using thermal models to describe the heat dissipation process of FCBGA is a significant topic in the field of ***,the thermal resistance model considering the structure of each part of the chip is still ambiguous and rare,but it is quite desirable in *** this work,we propose a detailed thermal resistance network model,and describe it by using thermal conduction resistance and thermal spreading *** a striking FCBGA case,we calculated the thermal resistance of each part of the structure according to the temperature field simulated by *** thermal resistance network can be used to predict the temperatures in the chip under different *** example,when the power changes by 40%,the relative error of junction temperature prediction is only 0.24%.The function of the detailed thermal resistance network in evaluating the optimization space and determining the optimization direction is *** work illustrates a potential thermal resistance analysis method for electronic devices such as FCBGA.

关键词： FCBGA package thermal resistance network thermal spreading resistance junction temperature

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Substantial increase of heat-induced labor and economic loss in China under rapid economic and environmental temperature growth

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Advances in Climate Change Research 2024年第4期15卷 708-716页

作者： Bo-Wen CHU Jian-Feng LUO ke-Xin WANG Zhen-Cheng xing Hai-Kun WANG Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric SciencesNanjing UniversityNanjing 210023China Collaborative Innovation Center of Climate Change Jiangsu ProvinceNanjing 210023China Frontiers Science Center for Critical Earth material Cycling Nanjing UniversityNanjing 210023China Nanjin-Helski Insiute in Amosperc and Earth System Sciences Nanjing UniversityNanjing 210023China

Exposure to heat stress causes diminished work performance and leads to economic *** the last two decades,China has experienced both rapid economic development and environmental warming;however,the spatiotemporal variations of association between environmental heat and labor loss have been rarely investigated behind this double ***,we evaluated the variation in China's heat-induced labor productivity loss and related economic cost from 2001 to 2019 and investigated the effect of economic development and regional *** found that decline in labor productivity because of heat stress increased significantly(pmanufacturing,contributed to larger proportions of economic *** transformation of industrial structure made economic sectors more vulnerable to heat exposure,and increasingly preventive effects of air-conditioning use were noted on economic damage due to heat-induced productivity decline(36.0%relative economic benefits in 2019 compared to 9.7%in 2001).Our findings could provide a deep insight into heat burden on occupational health and heat adaptation strategies regionally under climate change,especially in developing areas with higher temperature and humidity environment.

关键词： Heat stress Labor loss Wet bulb globe temperature China Economic impact

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Development of a Mengla virus minigenome and comparison of its polymerase complexes with those of other filoviruses

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Virologica Sinica 2024年第3期39卷 459-468页

作者： Shi-Zhe Xie ke Yao Bei Li Cheng Peng xing-Lou Yang Zheng-Li Shi State Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China Yunnan key Laboratory of Biodiversity Information Kunming Institute of ZoologyChinese Academy of SciencesKunming650201China Hubei Jiangxia Laboratory Wuhan430200China

Ebola virus(EBOV)and marburg virus(maRV),members of the Filoviridae family,are highly pathogenic and can cause hemorrhagic fevers,significantly impacting human *** are considered reservoirs of these viruses because related filoviruses have been discovered in ***,due to the requirement for maximum containment laboratories when studying infectious viruses,the characterization of bat filoviruses often relies on pseudoviruses and minigenome *** this study,we used RACE technology to sequence the 30-leader and 50-trailer of Mengla virus(MLAV)and constructed a *** to maRV,the transcription activities of the MLAV minigenome are independent of *** further assessed the effects of polymorphisms at the 50 end on MLAV minigenome activity and identified certain mutations that decrease minigenome reporter efficiency,probably due to alterations in the RNA secondary *** reporter activity upon recombination of the 30-leaders and 50-trailers of MLAV,maRV,and EBOV with those of the homologous or heterologous minigenomes was compared and it was found that the polymerase complex and leader and trailer sequences exhibit intrinsic ***,we investigated whether the polymerase complex proteins from EBOV and maRV support MLAV minigenome RNA synthesis and found that the homologous system is more efficient than the heterologous *** efficiently inhibited MLAV as well as EBOV *** summary,this study provides new information on bat filoviruses and the minigenome will be a useful tool for high-throughput antiviral drug screening.

关键词： Bat filovirus Mengla virus(MLAV) Minigenome Replication Antiviral drug screening

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Diagnostic performance of dynamic contrast-enhanced magnetic resonance imaging parameters and serum tumor markers in rectal carcinoma prognosis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1796-1807页

作者： Ren-Qi Mu Jun-Wei Lv Cai-Yun ma Xiao-Hui ma Dong xing Hou-Sheng ma Department of Radiology Yantai Mountain HospitalYantai 264001Shandong ProvinceChina Department of Radiology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina Department of Gynaecology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina The First Clinical Medical College Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina

BACKGROUND Rectal carcinoma(RC),one of the most common malignancies globally,presents an increasing incidence and mortality year by year,especially among young people,which seriously affects the prognosis and quality of life of *** present,dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters and serum carbohydrate antigen 19-9(CA19-9)and CA125 Levels have been used in clinical practice to evaluate the T stage and differentiation of ***,the accuracy of these evaluation modalities still needs further *** study explores the application and value of these methods in evaluating the T stage and differentiation degree of *** To analyze the diagnostic performance of DCE-MRI parameters combined with serum tumor markers(TMs)in assessing pathological processes and prognosis of RC *** A retrospective analysis was performed on 104 RC patients treated at Yantai Yuhuangding Hospital from may 2018 to January *** were categorized into stages T1,T2,T3,and T4,depending on their T stage and differentiation *** addition,they were assigned to low(L group)and moderate-high differentiation(M+H group)groups based on their differentiation *** levels of DCE-MRI parameters and serum CA19-9 and CA125 in different groups of patients were *** addition,the value of DCE-MRI parameters[volume transfer constant(Ktrans),rate constant(kep),and extravascular extracellular volume fraction(Ve)in assessing the differentiation and T staging of RC patients was ***,the usefulness of DCE-MRI parameters combined with serum CA19-9 and CA125 Levels in the evaluation of RC differentiation and T staging was *** Ktrans,Ve,CA19-9 and CA125 were higher in the high-stage group and L group than in the low-stage group and M+H Group,respectively(P<0.05).The areas under the curve(AUCs)of the Ktran and Ve parameters were 0.638 and 0.694 in the diagnosis of high and low stages,respectively,and 0.672 and 0

关键词： Rectal carcinoma Volume transfer constant Rate constant Extravascular extracellular volume fraction Serum carbohydrate antigen 19-9 Serum carbohydrate antigen 125

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Adaptable "bubble particles" prepared by green aqueous phase reshaping for completely removing odor

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Nano Research 2024年第3期17卷 2172-2180页

作者： Jiajia ma Yichang Xia Tienan Zhao Wenfeng Hu Weifeng Zhang Qinfei ke Yi Zhao Shanghai Frontiers Science Center of Advanced Textiles Donghua UniversityShanghai 201620China Engineering Research Center of Technical Textiles Ministry of EducationDonghua UniversityShanghai 201620China School of Fashion Engineering Central Laboratory Shanghai University of Engineering ScienceShanghai 201620China Department of materials Science and Engineering National University of SingaporeSingapore 117575Singapore School of Perfume and Aroma Technology Shanghai Institute of TechnologyShanghai 201418China

Facile and ecofriendly loading of micro/nano function-specific substances to create functional materials is a trend being pursued by ***,current micro/nano particles loading approaches are often hindered by issues such as uneven distribution,unsatisfactory stability and complicate *** this work,we present an aqueous phase reshaping method that only utilizes the moisture to fabricate the"bubble particles",which could perfectly cater to the topography of the *** green preparation of bubble particles adopts an absolutely zero-pollution method,realizing the firm loading of particles on the *** the preparation and loading of particles overcomes the traditional complicate process,while the aqueous phase reshaping ensures uniform and firm loading of the"bubble particles"onto the *** mechanism demonstrates a significant enhancement in the interface relation after aqueous phase reshaping,with a 121-fold increase in contact surface area achieved by reducing the height by 1μ***,we explore for the first time the influence of the nature of the receiving substrate on the interface morphology of particles during electrostatic spraying,which has important guiding significance for the interface relationship of electrostatic spraying and even electrostatic spinning *** also screen out the natural antibacterial essential oil linalool as the effective specialized antibacterial agent,which can specifically inhibit the odor-producing Proteus in urine,with an antibacterial rate of up to 100%.Taken together,this simple,ecofriendly method for fabricating functional materials with optimal interface stability appears highly promising for use in various products formed by electrostatic spraying/spinning.

关键词： bubble particle electrostatic spraying aqueous phase reshaping interface bonding remove odor nano spraying

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Analytical solution for the effective elastic properties of rocks with the tilted penny-shaped cracks in the transversely isotropic background

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Petroleum Science 2024年第1期21卷 221-243页

作者： Zheng-Qian ma xing-Yao Yin Zhao-Yun Zong Yuan-Yuan Tan Ya-Ming Yang National key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Pilot National Laboratory for marine Science and Technology(Qingdao) Qingdao266200ShandongChina

Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is ***,up to now,multitudinous analytical models focus primarily on the cracked rock with the isotropic background,while the explicit model for the cracked rock with the anisotropic background is rarely investigated in spite of such case being often encountered in the ***,we first studied dependences of the crack opening displacement tensors on the crack dip angle in the coordinate systems formed by symmetry planes of the crack and the background anisotropy,respectively,by forty groups of numerical *** on the conclusion from the experiments,the analytical solution was derived for the effective elastic properties of the rock with the inclined penny-shaped cracks in the transversely isotropic ***,we comprehensively analyzed,according to the developed model,effects of the crack dip angle,background anisotropy,filling fluid and crack density on the effective elastic properties of the cracked *** analysis results indicate that the dip angle and background anisotropy can significantly either enhance or weaken the anisotropy degrees of the P-and SH-wave velocities,whereas they have relatively small effects on the SV-wave velocity ***,the filling fluid can increase the stiffness coefficients related to the compressional modulus by reducing crack compliance parameters,while its effects on shear coefficients depend on the crack dip *** increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip *** comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness ***,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the or

关键词： Effective elastic property Tilted crack Transverse isotropy Analytical solution Crack opening displacement

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Nitrogen–sulfur co-doped porous carbon derived from asphalt as efficient catalyst for oxygen reduction

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Rare Metals 2024年第1期43卷 380-388页

作者： Jing-Sheng ma Ming-Zai Wu Ling Chen Li-xing Zhang Ying Xiong key Laboratory of Structure and Functional Regulation of Hybrid materials Ministry of EducationInstitute of EnergyHefei Comprehensive National Science CenterAnhui UniversityHefei 230601China

As an environment-friendly and low-cost petrochemical by-product, asphalt has great potential in the preparation of metal-free oxygen reduction electrocatalysts with excellent performance and outstanding stability. In this paper, we converted asphalt into porous carbon nanosheets by a simple activation method, using potassium citrate as the swelling agent.

关键词： stability porous catalyst

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A machine learning-based strategy for predicting the mechanical strength of coral reef limestone using X-ray computed tomography

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2790-2800页

作者： Kai Wu Qingshan Meng Ruoxin Li Le Luo Qin ke ChiWang Chenghao ma State key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China State key Laboratory of Water Resources and Hydropower Engineering Science Institute of Engineering Risk and Disaster PreventionWuhan UniversityWuhan430072China

Different sedimentary zones in coral reefs lead to significant anisotropy in the pore structure of coral reef limestone(CRL),making it difficult to study mechanical *** X-ray computed tomography(CT),112 CRL samples were utilized for training the support vector machine(SVM)-,random forest(RF)-,and back propagation neural network(BPNN)-based models,***,the machine learning model was embedded into genetic algorithm(GA)for parameter optimization to effectively predict uniaxial compressive strength(UCS)of *** indicate that the BPNN model with five hidden layers presents the best training effect in the data set of *** SVM-based model shows a tendency to overfitting in the training set and poor generalization ability in the testing *** RF-based model is suitable for training CRL samples with large *** of Pearson correlation coefficient matrix and the percentage increment method of performance metrics shows that the dry density,pore structure,and porosity of CRL are strongly correlated to ***,the P-wave velocity is almost uncorrelated to the UCS,which is significantly distinct from the law for homogenous *** addition,the pore tensor proposed in this paper can effectively reflect the pore structure of coral framework limestone(CFL)and coral boulder limestone(CBL),realizing the quantitative characterization of the heterogeneity and anisotropy of *** pore tensor provides a feasible idea to establish the relationship between pore structure and mechanical behavior of CRL.

关键词： Coral reef limestone(CRL) machine learning Pore tensor X-ray computed tomography(CT)

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Global Dynamics of a Kawasaki Disease Vascular Endothelial Cell Injury Model with Backward Bifurcation and Hopf Bifurcation

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Acta mathematicae Applicatae Sinica 2024年

作者： ke GUO Wan-biao ma School of mathematics and Physics University of Science and Technology Beijing

Kawasaki disease（KD） is an acute, febrile, systemic vasculitis that mainly affects children under five years of age. In this paper, we propose and study a class of 5-dimensional ordinary differential equation model describing the vascular endothelial cell injury in the lesion area of KD. This model exhibits forward/backward bifurcation. It is shown that the vascular injury-free equilibrium is locally asymptotically stable if the basic reproduction number R0manent if the basic reproduction number R0> 1, and some explicit analytic expressions of ultimate lower bounds of the solutions of the model are *** results suggest that the control of vascular injury in the lesion area of KD is not only correlated with the basic reproduction number R0, but also with the growth rate of normal vascular endothelial cells promoted by the vascular endothelial growth factor.

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