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Dynamic simulation insights into friction weakening effect on rapid long-runout landslides:A case study.of the yigong landslide in the Tibetan Plateau,China

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China Geology 2024年第2期7卷 222-236页

作者： Zi-zheng Guo Xin-yong Zhou Da Huang Shi-jie zhai Bi-xia Tian guang-ming Li School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Tianjin Municipal Engineering Design&Research Institute(TMEDI) Tianjin 300392China

This study proposed a novel friction law dependent on velocity,displacement and normal stress for kinematic analysis of runout process of rapid *** well-known yigong landslide occurring in the Tibetan Plateau of China was employed as the case,and the derived dynamic friction formula was included into the numerical simulation based on Particle Flow *** showed that the friction decreased quickly from 0.64(the peak)to 0.1(the stead value)during the 5s-period after the sliding initiation,which explained the behavior of rapid movement of the *** monitored balls set at different sections of the mass showed similar variation characteritics regarding the velocity,namely evident increase at the initial phase of the movement,followed by a fluctuation phase and then a stopping *** peak velocity was more than 100 m/s and most particles had low velocities at 300s after the landslide *** spreading distance of the landslide was calculated at the two-dimension(profile)and three-dimension scale,*** with the simulation result without considering friction weakening effect,our results indicated a max distance of about 10 km from the initial unstable position,which fit better with the actual situation.

关键词： Rapid long-runout landslide PFC Friction weakening Three-dimension Numerical simulation Tibetan Plateau Hydrogeology Engineering Geological hazards survey engineering

Androgen signaling inhibits de novo lipogenesis to alleviate lipid deposition in zebrafish

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Zoological Research 2024年第2期45卷 355-366页

作者： Jing-yi Jia guang-Hui Chen Ting-Ting Shu Qi-yong Lou Xia Jin Jiang-yan He Wu-Han Xiao Gang zhai Zhan yin College of Fisheries Huazhong Agriculture UniversityWuhanHubei 430070China State Key Laboratory.of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China Hubei Key Laboratory.of Three Gorges Project for Conservation of Fishes Chinese Sturgeon Research InstituteChina Three Gorges CorporationYichangHubei 443100China Hubei Hongshan Laboratory Huazhong Agriculture UniversityWuhanHubei 430070China Innovative Academy.of Seed Design Chinese Academy of SciencesBeijing 100049China

Testosterone is closely associated with lipid metabolism and known to affect body fat composition and muscle mass in ***,the mechanisms by which testosterone acts on lipid metabolism are not yet fully understood,especially in *** this study,cyp17a1-/-zebrafish(Danio rerio)exhibited excessive visceral adipose tissue(VAT),lipid content,and up-regulated expression and activity.of hepatic de novo lipogenesis(DNL)*** assay for transposase accessible chromatinwithsequencing(ATAC-seq)results demonstrated that chromatin accessibility.of DNL genes was increased in cyp17a1-/-fish compared to cyp17a1+/+male fish,including stearoyl-CoA desaturase(scd)and fatty acid synthase(fasn).Androgen response element(ARE)motifs in the androgen signaling pathway were significantly enriched in cyp17a1+/+male fish but not in cyp17a1-/-*** androgen receptor(ar)-/-and wildtype(WT)zebrafish administered with Ar antagonist flutamide displayed excessive visceral adipose tissue,lipid content,and up-regulated expression and activity.of hepatic de novo lipogenesis *** Ar agonist BMS-564929 reduced the content of VAT and lipid content,and down-regulated acetyl-CoA carboxylase a(acaca),fasn,and scd ***,the rescue effect of testosterone on cyp17a1-/-fish in terms of phenotypes was abolished when ar was additionally ***,these findings reveal that testosterone inhibits lipid deposition by down-regulating DNL genes via Ar in zebrafish,thus expanding our understanding of the relationship between testosterone and lipid metabolism in teleosts.

关键词： Cyp17a1 Testosterone Androgen receptor De novo lipogenesis Fatty acid synthesis

A CoMPACT EMBEDDING RESULT FoR NoNLoCAL SoBoLEV SPACES AND MULTIPLICITy.oF SIGN-CHANGING SoLUTIoNS FoR NoNLoCAL SCHRÖDINGER EQUATIoNS

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Acta Mathematica Scientia 2024年第5期44卷 1853-1876页

作者： Xu ZHANG Hao zhai Fukun ZHAo Department of Mathematics Wuhan University of TechnologyWuhan430070China Department of Mathematics Yunnan Normal UniversityKunming650500China

For any s∈(0,1),let the nonlocal Sobolev space X^(s)(ℝ^(N))be the linear space of Lebesgue measure functions fromℝN toℝsuch that any function u in X^(s)(ℝ^(N))belongs to L2(ℝN)and the function(x,y)\longmapsto\big(u(x)-u(y)\big)\sqrt{K(x-y)}is in L2(ℝN,ℝN).First,we show,for a coercive function V(x),the subspace E:=\bigg\{u\in X^s(\mathbb{R}^N):\int_{\mathbb{R}^N}V(x)u^2{\rm d}xy\bigg\}of X^(s)(ℝ^(N))is embedded compactly into L^(p)(ℝ^(N))for p\in[2,2_s^*),where 2_s^*is the fractional Sobolev critical *** terms of applications,the existence of a least energy sign-changing solution and infinitely many sign-changing solutions of the nonlocal Schrödinger equation-{\cal{L}_K}u+V(x)u=f(x,u),\x\in\\mathbb{R}^N are obtained,where-{\cal{L}_K}is an integro-differential operator and V is coercive at infinity.

关键词： sign-changing solution integro-differential operator least energy variational method

Extraordinary hot extreme in summer 2022 over the yangtze River basin modulated by the La Nina condition under global warming

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Advances in Climate Change Research 2024年第1期15卷 21-30页

作者： Zhen LIAo yu-Feng yUAN yang CHEN Pan-Mao zhai State Key Laboratory.of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

A widespread and prolonged hot extreme hit the yangtze River basin in summer 2022,with 300 sites established new temperature records and nearly 96%stations endured more than 40 hot *** the perspective of the combination effect of the global warming and La Nina condition,potential mechanisms of the hot extreme were *** a record-breaking hot extreme was caused by an extremely strong and westward-shifted western Pacific subtropical high(WPSH).The global warming effect contributed primarily to the abnormal hot days in the yangtze River basin,coupled with the modulation of the La Nina *** sea surface temperature anomaly pattern under La Nina condition favored more convection activities over the western Pacific,encouraging an enhanced and westward-extended *** addition,an observation-based attribution analysis indicates that anthropogenic warming may increase the probability.of such extensively persistent hot extremeby1.8 times.

关键词： Hot extreme The yangtze River basin Global warming Tropical Pacific forcing

Recent Advances in Biomass-derived Porous Carbon Materials:Synthesis,Composition and Applications

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Chemical Research in Chinese Universities 2024年第1期40卷 3-19页

作者： zhai Ziqi LU yumiao LIU guangyong DING Wei-Lu CAo Bobo HE Hongyan CAS Key Laboratory.of Green Process and Engineering State Key Laboratory of Mesoscience and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China University.of Chinese Academy.of Sciences Beijing 100049P.R.China Longzihu New Energy Laboratory Zhengzhou Institute of Emerging Industrial TechnologyZhengzhou 450000P.R.China

Porous carbon materials(PCMs)play a pivotal role in diverse applications,such as energy storage,adsorption,catalysis,environmental remediation,and microwave *** selection of carbon precursors,in particular,is crucial for tailoring porous structures with specific ***,with its rich carbon feedstock,abundant availability,renewability,and versatile structures,has emerged as a promising precursor for porous carbon material *** review comprehensively summarizes the recent advances in biomass-derived porous carbon materials(BPCMs)encompassing synthetic strategy,morphology,structural composition,and multiple *** first review synthetic approaches aiming at regulating porosity,followed by morphological and composition features of BPCMs,with a special emphasis on elucidating the dimensional clarification and heteroatom doping *** discussion then extends to the wide-ranging applications of BPCMs,covering energy-related applications and Co_(2) adsorption to environmental ***,the review outlines the existing challenges and prospects in the *** summary,this review systematically describes BPCMs and provides valuable guidance for researchers to select and synthesize BPCMs that meet specific functional requirements.

关键词： Biomass Porous carbon Py.olysis Heteroatom-doping Supercapacitor Co_(2)adsorption

Double enzyme mimetic activities of multifunctional Ag nanoparticle-decorated Co_(3)V_(2)o_(8)hollow hexagonal prismatic pencils for application in colorimetric sensors and disinfection

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Nano Materials Science 2024年第2期6卷 244-255页

作者： ying Gao Peng Ju yu Zhang yuxin Zhang Xiaofan zhai Jizhou Duan Baorong Hou Key Laboratory.of Marine Environmental Corrosion and Bio-fouling Institute of OceanologyChinese Academy of SciencesQingdao266071PR China Key Laboratory.of Marine Eco-Environmental Science and Technology Marine Bioresource and Environment Research CenterFirst Institute of OceanographyMinistry of Natural ResourcesQingdao266061PR China University.of Chinese Academy.of Sciences Beijing100049PR China open Studio for Marine Corrosion and Protection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao266071PR China Center for ocean Mega-Science Chinese Academy of SciencesQingdao266071PR China College of Materials Science and Engineering Chongqing UniversityChongqing400044China

Since the catalytic activity.of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like *** this work,Co_(3)V_(2)o_(8)with hollow hexagonal prismatic pencil structures were prepared as novel artificial enzyme *** were then decorated by photo-depositing Ag nanoparticles(Ag NPs)on the surface to further improve its catalytic *** Ag NPs decorated Co_(3)V_(2)o_(8)(ACVPs)showed both excellent oxidase-and peroxidase-like catalytic *** can oxidize the colorless 3,3’,5,5’-tetramethylbenzidine rapidly to induce a blue *** enhanced enzyme mimetic activities can be attributed to the surface plasma resonance(SPR)effect of Ag NPs as well as the synergistic catalytic effect between Ag NPs and Co_(3)V_(2)o_(8),accelerating electron transfer and promoting the catalytic *** were applied in constructing a colorimetric sensor,validating the occurrence of the Fenton reaction,and disinfection,presenting favorable catalytic *** enzyme-like catalytic mechanism was studied,indicating the chief role of⋅o_(2)-radicals in the catalytic *** work not only discovers a novel functional material with double enzyme mimetic activity but also provides a new insight into exploiting artificial enzyme mimics with highly efficient catalytic ability.

关键词： Co_(3)V_(2)o_(8) Ag NPs Enzyme mimetic Colorimetric sensor Disinfection

High performance receiving and processing technology in satellite beam hopping communication

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Journal of Systems Engineering and Electronics 2024年第4期35卷 815-828页

作者： zhai Shenghua HUI Tengfei GoNG Xianfeng ZHANG Zehui GAo Xiaozheng yANG Kai School of Communication Engineering Xi’Dian UniversityXian 710126China CAST(China Academy.of Space Technology)-Xi’an Institute of Space Radio Technology Xi’an 710010China School of Cyberspace Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and ***,beam hopping causes the traditional continuous time-division multiplexing signal in the forward downlink to become a burst signal,satellite terminal receivers need to solve multiple key issues such as burst signal rapid synchronization and high-per-formance ***,this paper analyzes the key issues of burst communication for traffic signals in beam hopping sys-tems,and then compares and studies typical carrier synchro-nization algorithms for burst ***,combining the requirements of beam-hopping communication systems for effi-cient burst and low signal-to-noise ratio reception of downlink signals in forward links,a decoding assisted bidirectional vari-able parameter iterative carrier synchronization technique is pro-posed,which introduces the idea of iterative processing into car-rier *** at the technical characteristics of communication signal carrier synchronization,a new technical approach of bidirectional variable parameter iteration is adopted,breaking through the traditional understanding that loop struc-tures cannot adapt to low signal-to-noise ratio burst ***,combining the DVB-S2X standard physical layer frame format used in high throughput satellite communication systems,the research and performance simulation are *** results show that the new technology proposed in this paper can significantly shorten the carrier synchronization time of burst signals,achieve fast synchronization of low signal-to-noise ratio burst signals,and have the unique advantage of flexible and adjustable parameters.

关键词： beam-hopping high throughput satellite high per-formance reception processing

Inner-shell ionization cross sections of atoms by positron impact

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Communications in Theoretical Physics 2024年第6期76卷 142-147页

作者： yuan-Cheng Wang Jia Ma Li-guang Jiao Stephan Fritzsche College of Physical Science and Technology Shenyang Normal UniversityShenyang 110034China Helmholtz-Institut Jena D-07743 JenaGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH D-64291 DarmstadtGermany College of Science Shenyang Aerospace UniversityShenyang 110136China College of Physics Jilin UniversityChangchun 130012China Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena07743 JenaGermany

The relativistic binary-encounter-Bethe model with Wannier-type threshold law is employed to obtain the inner-shell ionization cross sections of multi-electron atoms(Ni,Cu,y,Ag,Au,yb,Ta,and Pb)for positron impact energies from the thresholds up to 105ke *** is good agreement between the present calculations and the experimental *** constant in the acceleration term derived from the Wannier law is determined to be 0.2 and 0.5 for the K-and L-shells,respectively.

关键词： positron scattering ionization cross section binary-encounter-Bethe model

Liquid-phase epitaxial layer by layer brushing fabrication of metalorganic frameworks films

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Nano Research 2024年第6期17卷 5698-5704页

作者： Li-Mei Chang Rui zhai Zhi-Zhou Ma Jian-Dong Huang Zhi-Gang Gu Jian Zhang College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory.of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University.of Chinese Academy.of Sciences Beijing 100049China

Development of metal-organic framework(MoF)films is of great importance to expand their ***,we report a facile and universal method of liquid-phase epitaxial(LPE)layer by layer(LBL)brushing approach for fabricating MoF films on various substrates in a high-throughput *** MoF films preparation method offers a great prospective to cost-effectively construct films with short preparation time and little reagent ***,this LBL brushing approach has been implemented successfully to assemble various MoF films,including HKUST-1,zeolitic imidazolate framework-8(ZIF-8),Cu(bdc),and Cu_(2)(L)_(2)P(L=bdc,ndc,and cam;P=dabco and bipy).Afterwards,the classic MoF HKUST-1 and ZIF-8 films were grown on sensor chip electrode and porous fiber support for good volatile organic compounds(VoCs)selective sensing and water purification *** study demonstrates that this LBL brushing preparation method can be employed to synthesize various MoF films with a variety.of characteristics to realize their sensing and separation applications.

关键词： metal-organic framework porous materials layer by layer fabrication film