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Characteristic stress and strain precursor information for fine-grained granite during failure process under triaxial loading and unloading conditions

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Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第1期3卷 105-114页

作者： zhen peng Xing Su Yuda Chen Jianqiang Xia Diyuan Li School of Resources and Safety Engineering Central South UniversityChangsha410083China China Energy Engineering Group Guangdong Electric Power Design Institute Co. Ltd.Guangzhou510663China

The unloading effect by excavation may cause irreversible and severe damage to the surrounding rock masses in underground *** this paper,both conventional triaxial compression(CTC)tests and triaxial unloading confining pressure(TUCP)tests were conducted on fine-grained granite to study its triaxial compression failure processes due to *** on the crack volumetric strain(CVS)method,the crack axial strain(CAS)method and crack radial area strain(CRAS)method were proposed to identify the failure precursor information(including stress thresholds and axial strain at the initiation point of crack connectivity stage)during the rock failure *** results of the CTC tests show that the stable crack development stressσsd,unstable crack development stressσusd,and crack connectivity stressσct identified by the CAS method are 6%,74%–84%,and 86%–97%of the peak stress,*** the TUCP cases,as the confining pressure increases,the stress thresholds,axial pressure at failure and axial strain at the start of the crack connectivity stage increase,while the time ratio of the crack connectivity stage to the entire unloading stage *** indicates that fine-grained granite is prone to generate more cracks and leads to fail suddenly under high confining ***,this new method demonstrates that the point at which the derivative of the radial crack area strain transitions from stable to a sudden increase or decrease is defined as the precursor point of rock *** results of axial strain at the starting point of the crack connectivity stage are very close to those predicted by the AE method,withβ1 no more than 11%.

关键词： Conventional triaxial compression test Triaxial unloading confining pressure test Stress thresholds Volumetric strain Acoustic emission

Twinning aspects and their efficient roles in wrought Mg alloys:A comprehensive review

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Journal of Magnesium and Alloys 2024年第6期12卷 2201-2230页

作者： S.S.A.Shah Manping Liu Azim Khan Farooq Ahmad M.R.Abdullah Xingquan Zhang Shiwei Xu zhen peng School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China School of Mechanical Engineering Anhui University of TechnologyMáanshan 243002China College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China

Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium(Mg)***,twins play a crucial role in initiating dynamic recrystallization(DRX),while twin regions experience rapid recrystallization during static recrystallization(SRX).The activation of twinning can lead to changes in lattice orientation,significantly impacting the final texture in Mg *** active roles of twinning are influenced by various factors during the activation process,and the mobility of twin boundaries(TB)can be amplified by stress effects,dislocation interactions,and thermal ***,annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them,restraining their *** such as segregation may also alter the twinning propensity in Magnesium-rare earth(Mg-RE)***{10–11}contraction twins(CT)and{10–11}-{10–12}double twins(DT)can promote dynamic recrystallization(DRX),they also pose a risk as potential sources of voids and ***,understanding the nucleation and growth mechanisms of twinning is crucial,and these aspects are briefly reviewed in this *** the factors mentioned above,this article summarizes the recent research progress in this field,shedding light on advancements in recent eras.

关键词： Mg alloys Twinning Recrystallization Texture Mechanical properties

Percutaneous ultrasound-guided coaxial core needle biopsy for the diagnosis of multiple splenic lesions: A case report

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 616-621页

作者： Sha-Hong Pu Wu-Yong-Ga Bao zhen-peng Jiang Rui Yang Qiang Lu Department of Medical Ultrasound West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND The overlap of imaging manifestations among distinct splenic lesions gives rise to a diagnostic ***,a definitive diagnosis primarily relies on his-tological *** ultrasound(US)-guided coaxial core needle biopsy(CNB)not only procures sufficient tissue to help clarify the diagnosis,but reduces the incidence of puncture-related *** SUMMARY A 41-year-old female,with a history of pulmonary tuberculosis,was admitted to our hospital with multiple indeterminate splenic ***-scale ultrasono-graphy demonstrated splenomegaly with numerous well-defined hypoechoic *** contrast-enhanced computed tomography(CT)showed an en-larged spleen with multiple irregular-shaped,peripherally enhancing,hypodense *** emission CT revealed numerous abnormal hyperglycemia *** imaging findings strongly indicated the possibility of infectious disease as the primary concern,with neoplastic lesions requiring *** obtain the precise pathological diagnosis,the US-guided coaxial CNB of the spleen was ca-rried *** patient did not express any discomfort during the *** Percutaneous US-guided coaxial CNB is an excellent and safe option for obtaining precise splenic tissue samples,as it significantly enhances sample yield for exact pathological analysis with minimum trauma to the spleen parenchyma and sur-rounding tissue.

关键词： Spleen Splenic disease Ultrasound Biopsy Ultrasound-guided coaxial core needle biopsy Case report

Genetic dissection and origin of pleiotropic loci underlying multilevel fiber quality traits in upland cotton(Gossypium hirsutum L.)

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Journal of Integrative Agriculture 2024年第10期23卷 3250-3263页

作者： Hongge Li Shurong Tang zhen peng Guoyong Fu Yinhua Jia Shoujun Wei Baojun Chen Muhammad Shahid Iqbal Shoupu He Xiongming Du zhengzhou Research Base State Key Laboratory of Cotton Bio-breeding and Integrated Utilization/School of Agricultural SciencesZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Cotton Bio-breeding and Integrated Utilization/Institute of Cotton Research Chinese Academy of Agricultural SciencesAnyang 455000China

Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile ***,the limitations of measurement instruments have hindered the accurate evaluation of some important fiber characteristics such as fiber maturity,fineness,and neps,which in turn has impeded the genetic improvement and industrial utilization of cotton ***,12 single fiber quality traits were measured using Advanced Fiber Information System(AFIS)equipment among 383 accessions of upland cotton(Gossypium hirsutum L.).In addition,eight conventional fiber quality traits were assessed by the High Volume Instrument(HVI)***-wide association study(GWAS),linkage disequilibrium(LD)block genotyping and functional identification were conducted sequentially to uncover the associated elite loci and candidate genes of fiber quality *** a result,the previously reported pleiotropic locus FL_D11 regulating fiber length-related traits was identified in this *** importantly,three novel pleiotropic loci(FM_A03,FF_A05,and FN_A07)regulating fiber maturity,fineness and neps,respectively,were detected based on AFIS *** highly promising candidate genes were screened out by integrating RNA-seq and qRT-PCR analyses,including the reported GhKRP6 for fiber length,the newly identified GhMAP8 for maturity and GhDFR for *** origin and evolutionary analysis of pleiotropic loci indicated that the selection pressure on FL_D11,FM_A03 and FF_A05 increased as the breeding period approached the present and the origins of FM_A03 and FF_A05 were traced back to cotton *** findings reveal the genetic basis underlying fiber quality and provide insight into the genetic improvement and textile utilization of fiber in ***.

关键词： upland cotton single fiber quality pleiotropic loci candidate genes locus origin

Preparation of tungsten-particle-reinforced Zr-based bulk metallic glass composites by two-step spark plasma sintering:microstructure evolution,densification mechanism and mechanical properties

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Rare Metals 2024年第4期43卷 1793-1808页

作者： Yun-Fei Ma Pan Gong Mao Zhang Hui-EHu zhen peng Xiao Xu Xin Wang Mehdi Malekan Xue-Feng Tang Lei Deng Jun-Song Jin Xin-Yun Wang State Key Laboratory of Materials Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Research Institute of Huazhong University of Science and Technology in Shenzhen Shenzhen518057China Department of Chemistry and Materials Naval University of EngineeringWuhan430032China School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China College of Machine Shanghai Dianji UniversityShanghai201306China School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

A new two-step spark plasma sintering(TSS)process with low-temperature pre-sintering and high-temperature final sintering has been successfully applied to prepare the tungsten-particle(Wp)-reinforced bulk metallic glass composites(Wp/BMGCs).Compared to normal spark plasma sintering(NS),the densification rate and relative density of Wp/BMGCs can be improved by selecting TSS with appropriate sintering pressure in the low temperature pre-sintering ***,the compressive strength and plastic strain of 30%Wp/BMGCs prepared by TSS are both higher than those of the samples prepared by *** TSS process can significantly enhance the compressive strength of 30%Wp/BMGCs by 12%and remarkably increase the plastic strain by 50%,while the trend is completely opposite for 50%Wp/***-in situ experiments and finite element simulations reveal that uneven temperature distribution among particles during low-temperature pre-sintering causes local overheating at contact points between particles,accelerating formation of sintering neck between particles and plastic deformation of *** the volume fraction of Wp is low,TSS can improve the interface bonding between particles by increasing the number of sintering *** makes the fracture mode of Wp/BMGCs being predominantly transgranular ***,as the volume fraction of Wp increases,the adverse effects of Wp plastic deformation are becoming more and more *** aggregated Wp tends to form a solid"cage structure"that hinders the bonding between particles at the interface;correspondingly,the fracture behavior of Wp/BMGCs is mainly dominated by intergranular ***,reducing the sintering pressure during the low-temperature pre-sintering stage of TSS has been shown to effectively decrease plastic deformation in Wp,resulting in a higher degree of densification and better mechanical properties.

关键词： Bulk metallic glass composites Tungsten particle Two-step spark plasma sintering Densification mechanism Mechanical properties

Low-noise and low-power pixel sensor chip for gas pixel detectors

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Nuclear Science and Techniques 2024年第3期35卷 142-152页

作者： Zhuo Zhou Shi-Qiang Zhou Dong Wang Xiang-Ming Sun Chao-Song Gao peng-zhen Zhu Wei-Ping Ren Jun Liu Mu-Xian Li Chen Lian Chun-Lai Dong PLAC Key Laboratory of Quark and Lepton Physics(MOE)Central China Normal UniversityWuhan 430079China

Topmetal-M2 is a large-area pixel sensor chip fabricated using the GSMC 130 nm CMOS process in *** pixel array of Topmetal-M2 consists of pixels of 400 rows×512 columns with a pixel pitch of 45μm×45μ*** array is divided into 16 subarrays,with pixels of 400 rows×32 columns per *** pixel incorporates two charge sensors:a diode sensor and a Topmetal *** in-pixel circuit primarily consists of a charge-sensitive amplifier for energy measurements,a discriminator with a peak-holding circuit,and a time-to-amplitude converter for time-of-arrival *** pixel of Topmetal-M2 has a charge input range of~0-3 k e-,a voltage output range of~0-180 mV,and a charge-voltage conversion gain of~59.56μV∕e-.The average equivalent noise charge of Topmetal-M2,which includes the readout electronic system noise,is~43.45 e-.In the scanning mode,the time resolution of Topmetal-M2 is 1 LSB=1.25μs,and the precision is^()7.41μ*** an operating voltage of 1.5 V,Topmetal-M2 has a power consumption of~49 mW∕cm~*** this article,we provide a comprehensive overview of the chip architecture,pixel working principles,and functional behavior of ***,we present the results of preliminary tests conducted on Topmetal-M2,namely,alpha-particle and soft X-ray tests.

关键词： Charge collection Gas detectors Semiconductor detectors X-ray detectors

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优秀民族医药文化法治保障研究

广西民族大学学报（哲学社会科学版） 2024年第1期46卷 146-155页

作者：彭振广西民族大学法学院广西南宁530006 广西民族大学民族法与区域治理研究协同创新中心广西南宁530006

优秀民族医药作为中华优秀传统文化的一部分,是铸牢中华民族共同体意识的重要内容之一。近年来,国家高度重视民族医药的法治保障,已初步形成了较为完善的优秀民族医药法律保护体系。然而,由于民族医药本身的特殊性等因素,当前民族医药... 详细信息

优秀民族医药作为中华优秀传统文化的一部分,是铸牢中华民族共同体意识的重要内容之一。近年来,国家高度重视民族医药的法治保障,已初步形成了较为完善的优秀民族医药法律保护体系。然而,由于民族医药本身的特殊性等因素,当前民族医药在发展中还存在保护范围有待扩大和明确、存续的场域法律保障不足、发展和传承法治保障乏力、相关立法的可操作性和地方特色不强等问题。对此,应当构建统一协调的法律保护体系,依法优化民族医药准入制度,依法完善民族医药文化保障制度,依法健全民族医药监管制度,以及依法保障民族医药文化发展的正确导向。

关键词：铸牢中华民族共同体意识优秀民族文化民族医药法治保障

Recent Advances in Reconfigurable Electromagnetic Surfaces:Engineering Design,Full-Wave Analysis,and Large-Scale Optimization

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Electromagnetic Science 2024年第3期2卷 1-25页

作者： Incheol(Aiden)Jung zhen peng Yahya Rahmat-Samii Department of Electrical and Computer Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Department of Electrical and Computer Engineering University of CaliforniaLos AngelesLos AngelesCA 90024USA

This paper presents a comprehensive review of recent advances in reconfigurable electromagnetic(EM)*** discussion is organized around three key aspects of reconfigurable EM surfaces:unit cell engineering design,full-wave numerical analysis,and large-scale optimization *** references are provided to facilitate further exploration of this compelling and timely *** address the above three key aspects,we conduct an extensive examination of the design process for metasurfaces in reconfigurable *** involves evaluating the design methodology of unit cells,EM simulation techniques tailored for highly complex structures,and innovative optimization methods suitable for scenarios with numerous *** scenarios featuring reconfigurability for real-time manipulation of EM waves to meet the requirements of emerging communication environments,the optimization cost function is defined with multiple variables,exhibiting intricate behavior in the design ***,it necessitates an optimization methodology capable of handling high-dimensional functions without getting trapped in local ***,the intricate geometries of metasurface devices preclude analytical solutions,necessitating high-performance full-wave solvers capable of providing highly accurate simulations with minimal computational *** concepts and details pertaining to the aforementioned design stages are presented in a unified manner,along with representative examples.

关键词： Electromagnetic surface Full-wave simulation Metasurface Metasurface unit cell design Optimization Reconfigurable intelligent surface

Genomic variation,environmental adaptation,and feralization in ramie,an ancient fiber crop

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Plant Communications 2024年第8期5卷 189-207页

作者： Zeng-Yuan Wu Mark A.Chapman Jie Liu Richard I.Milne Ying Zhao Ya-Huang Luo Guang-Fu Zhu Marc W.Cadotte Ming-Bao Luan peng-zhen Fan Alex K.Monro Zhi-peng Li Richard T.Corlett De-Zhu Li Germplasm Bank of Wild Species&Yunnan Key Laboratory of Crop Wild Relatives Omics Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China School of Biological Sciences University of SouthamptonSouthampton SO171BJUK CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Institute of Molecular Plant Sciences School of Biological SciencesUniversity of EdinburghEdinburgh EH93JHUK Department of Biological Sciences University of Toronto-ScarboroughTorontoOntarioCanada Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangshaHunan 410205China Royal Botanic Gardens Kew RichmondSurrey TW93AEUK Center for Integrative Conservation and Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunYunnan 666303China

Feralization is an important evolutionary process,but the mechanisms behind it remain poorly ***,we use the ancient fiber crop ramie(Boehmeria nivea(L.)Gaudich.)as a model to investigate genomic changes associated with both domestication and *** first produced a chromosome-scale de novo genome assembly of feral ramie and investigated structural variations between feral and domesticated ramie ***,we gathered 915 accessions from 23 countries,comprising cultivars,major landraces,feral populations,and the wild *** on whole-genome resequencing of these accessions,we constructed the most comprehensive ramie genomic variation map to ***,demographic,and admixture signal detection analyses indicated that feral ramie is of exoferal or exo-endo origin,i.e.,descended from hybridization between domesticated ramie and the wild progenitor or ancient *** ramie has higher genetic diversity than wild or domesticated ramie,and genomic regions affected by natural selection during feralization differ from those under selection during *** analyses showed that feral and domesticated ramie have similar ecological niches that differ substantially from the niche of the wild progenitor,and three environmental variables are associated with habitat-specific adaptation in feral *** findings advance our understanding of feralization,providing a scientific basis for the excavation of new crop germplasm resources and offering novel insights into the evolution of feralization in nature.

关键词： ramie fiber offering