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由超拍电子伏特加速器产生的超高能伽马射线气泡

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Science Bulletin 2024年第4期69卷 449-457页

作者： LHAASO Collaboration zhen Cao Chuandong Gao Cong Li Ruo-Yu Liu Ruizhi Yang 不详 Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China TIANFU Cosmic Ray Research Center ChengduChina Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China University of Science and Technology of China Hefei 230026China

We report the detection of aγ-ray bubble spanning at least 100deg2 in ultra-high energy(UHE)up to a few PeV in the direction of the star-forming region Cygnus X,implying the presence super PeVatron(s)accelerating protons to at least 10 PeV.A log-parabola form with the photon indexΓ(E)=(2.71±0.02)+(0.11±0.02)×log10(E/10 TeV)is found fitting the gamma-ray energy spectrum of the bubble *** sources,“hot spots”correlated with very massive molecular clouds,and a quasi-spherical amorphousγ-ray emitter with a sharp central brightening are observed in the *** the core of~0.5°,spatially associating with a region containing massive OB association(Cygnus OB2)and a microquasar(Cygnus X-3),as well as previously reported multi-TeV sources,an enhanced concentration of UHEγ-rays is observed with 2 photons at energies above 1 *** general feature of the bubble,the morphology,and the energy spectrum,are reasonably reproduced by the assumption of a particle accelerator in the core,continuously injecting protons into the ambient medium.

关键词： Cosmic rays γ-rays Interstellar medium Star cluster

Chinese Expert Consensus on the Diagnosis and Treatment of Adult Dermatomyositis (2022)#

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International Journal of Dermatology and Venereology 2024年第3期7卷 163-173页

作者： Cao H. Chen A.-J. Cui Y. Deng D.-Q. Gao X.-H. He Y.-L. Kang X.-J. Jin H.-z. Li C.-X. Li F. Li H.-J. Liao W.-J. Liu X.-m. Lu Q.-J. Lu Y. Pan m. Pan W.-H. Shu X.-m. Sun Q. Tang K.-Y. Tao J. Wang Y. Xiao T. zhang F.-R. zhang H.-L. Department of Dermatology Ruijin Hospital Affiliated Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Department of Dermatology First Affiliated Hospital of Chongqing Medical University Chongqing 400042 China Department of Dermatology China-Japan Friendship Hospital Beijing 100029 China Department of Dermatology The Second Affiliated Hospital of Kunming Medical University Yunnan Kunming 650101 China Department of Dermatology The First Hospital of China Medical University Liaoning Shenyang 110001 China Department of Dermatology Beijing Chaoyang Hospital Affiliated to Capital Medical University Beijing 100020 China Department of Dermatology and Venereology People's Hospital of Xinjiang Uygur Autonomous Region Xinjiang Uygur Autonomous Region Urumqi 830001 China Department of Dermatology State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College Hospital Chinese Academy of Medical Science Peking Union Medical College Beijing 100730 China Department of Dermatology First Medical Center PLA General Hospital Beijing 100853 China Department of Dermatology Hainan Hospital of PLA General Hospital Hainan Sanya 572013 China Department of Dermatology Xijing Hospital Air Force Medical University Shaanxi Xi'an 710032 China Department of Dermatology Huazhong University of Science and Technology Union Shenzhen Hospital Guangdong Shenzhen 518052 China Hospital for Skin Diseases Institute of Dermatology Chinese Academy of Medical Sciences Peking Union Medical College Jiangsu Nanjing 210042 China Department of Dermatology Jiangsu Province Hospital The First Affiliated Hospital Nanjing Medical University Jiangsu Nanjing 210029 China Department of Dermatology Shanghai Changzheng Hospital Second Affiliated Hospital of Naval Medical University Shanghai 200003 China Department of Rheumatology China-Japan Friendship Hospital Beijing 100029 China Department of Dermatology Qilu Hospital of Shandong Universit

Dermatomyositis, an idiopathic inflammatory myopathy, is characterized by distinctive skin manifestations, proximal muscle weakness, and multiple organ involvement and can be accompanied by malignancies. To provide a reference for dermatologists and clinicians in other relevant fields of clinical practice, experts from the Dermatology Branch of the China International Exchange and Promotion Association for medical and Health Care and the National Clinical Research Center for Dermatologic and Immunologic Diseases developed this consensus on the diagnosis and treatment of adult dermatomyositis using Chinese and international literature and expert advice. © 2024 Wolters Kluwer Health. All rights reserved.

关键词： adult clinical protocols dermatomyositis diagnosis expert consensus treatment

Universal basis underlying temperature, pressure and size induced dynamical evolution in metallic glass-forming liquids

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Chinese Physics B 2024年第1期33卷 134-142页

作者：张华平范蓓蓓吴佳琦李茂枝 Department of Physics Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano DevicesRenmin University of ChinaBeijing 100872China Songshan Lake materials Laboratory Dongguan 523808China Key Laboratory of Quantum State Construction and manipulation Renmin University of ChinaBeijing 100872China

The dramatic temperature-dependence of liquids dynamics has attracted considerable scientific interests and efforts in the past decades, but the physics of which remains elusive. In addition to temperature, some other parameters, such as pressure, loading and size, can also tune the liquid dynamics and induce glass transition, which makes the situation more complicated. Here, we performed molecular dynamics simulations for Ni_(50)zr_(50) bulk liquid and nanodroplet to study the dynamics evolution in the complex multivariate phase space, especially along the isotherm with the change of pressure or droplet size. It is found that the short-time Debye–Waller factor universally determines the long-time relaxation dynamics no matter how the temperature, pressure or size changes. The basic correlation even holds at the local atomic scale. This finding provides general understanding of the microscopic mechanism of dynamic arrest and dynamic heterogeneity.

关键词： metallic glass-forming liquids structure relaxation dynamical heterogeneity Debye–Waller factor

Enhanced angiogenesis in porous poly(ε-caprolactone) scaffolds fortified with methacrylated hyaluronic acid hydrogel after subcutaneous transplantation

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Biomaterials Translational 2024年第1期5卷 59-68页

作者： Yang H. zheng m. zhang Y. Li C. Lai J.H.C. zhang Q. Chan K.W.Y. Wang H. zhao X. Yang z. Xu C. Department of Biomedical Engineering City University of Hong Kong Hong Kong Center for Pluripotent Stem Cell Research and Engineering Research Institute of Tsinghua Guangdong Province Guangzhou China Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic University Hong Kong

A composite scaffold composed of a porous scaffold and hydrogel filling can facilitate engraftment, survival, and retention in cell transplantation processes. This study presents a composite scaffold made of poly(ε-caprolactone) (PCL) and methacrylated hyaluronic acid (meHA) hydrogel and describes the corresponding physical properties (surface area, porosity, and mechanical strength) and host response (angiogenesis and fibrosis) after subcutaneous transplantation. Specifically, we synthesise meHA with different degrees of substitution and fabricate a PCL scaffold with different porosities. Subsequently, we construct a series of PCL/meHA composite scaffolds by combining these hydrogels and scaffolds. In experiments with mice, the scaffold composed of 3% PCL and 10–100 kDa, degree of substitution 70% meHA results in the least fibrosis and a higher degree of angiogenesis. This study highlights the potential of PCL/meHA composite scaffolds for subcutaneous cell transplantation, given their desirable physical properties and host response. © 2024, Chinese medical multimedia Press Co Ltd. All rights reserved.

关键词： angiogenesis cell transplantation hyaluronic acid poly(ε-caprolactone) scaffold

Evaluating ultrasound signals of carbon steel fatigue testing using signal analysis approaches

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Journal of Central South University 2014年第1期21卷 232-241页

作者： m.m.Padzi S.Abdullah m.z.Nuawi S.m.Beden z.m.Nopiah Department of mechanical and materials Engineering Universiti Kebangsaan Malaysia

The application of ultrasound techniques to monitor the condition of structures is becoming more prominent because these techniques can detect the early symptoms of defects such as cracks and other *** early detection of defects is of vital importance to avoid major failures with catastrophic *** assessment of an ultrasound technique was used to investigate fatigue damage *** tests were performed according to the ASTm E466-96 standard with the attachment of an ultrasound sensor to the test *** 1045 carbon steel was used due to its wide application in the automotive industry.A fatigue test was performed under constant loading stress at a sampling frequency of 8 *** sets of data acquisition systems were used to collect the fatigue strain signals and ultrasound *** of the signals were edited and analysed using a signal processing *** methods were used to evaluate the signals,the integrated Kurtosis-based algorithm for z-filter technique(I-kaz) and the short-time Fourier transform(STFT).The fatigue damage behaviour was observed from the initial stage until the last stage of the fatigue *** results of the I-kaz coefficient and the STFT spectrum were used to explain and describe the behaviour of the fatigue damage.I-kaz coefficients were ranged from 60 to 61 for strain signals and ranged from 5 to 76 for ultrasound signals.I-kaz values tend to be high at failure point due to high amplitude of respective *** spectrogram displays the colour intensity which represents the damage severity of the strain signals.I-kaz technique is found very useful and capable in assessing both stationary and non-stationary signals while STFT technique is suitable only for non-stationary signals by displaying its spectrogram.

关键词： fatigue ultrasound signal analysis integrated Kurtosis-based algorithm for z-filter technique short-time Fouriertransform

青藏高原及其周边二叠纪综合地层、生物群以及古地理和古气候演化

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中国科学：地球科学 2024年第4期54卷 1125-1170页

作者：沈树忠张以春袁东勋徐海鹏琚琦张华郑全锋罗茂侯章帅南京大学地球科学与工程学院内生金属矿床成矿机制研究国家重点实验室关键地球物质循环前沿科学中心南京210023 中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学南京学院南京210049 中国矿业大学资源与地球科学学院徐州221116

二叠纪是青藏高原各块体演化的关键时段,发生了一系列重大地质和生物事件,当时横跨南北半球统一的泛大陆演化到了鼎盛阶段,阻断了全球东西向的赤道暖流的同时,在泛大陆的东侧形成了一个半封闭的、具有重要历史意义的特提斯洋暖池,是古-... 详细信息

二叠纪是青藏高原各块体演化的关键时段,发生了一系列重大地质和生物事件,当时横跨南北半球统一的泛大陆演化到了鼎盛阶段,阻断了全球东西向的赤道暖流的同时,在泛大陆的东侧形成了一个半封闭的、具有重要历史意义的特提斯洋暖池,是古-中生代之交生物与环境演变的引擎.青藏高原二叠纪地层分布广泛、化石丰富,从南到北由于跨越不同的纬度带体现出不同的特点.雅鲁藏布江以南的喜马拉雅特提斯带当时位于冈瓦纳大陆印度板块北缘,整个二叠纪沉积含有典型的冈瓦纳冷水型生物群;雅鲁藏布江缝合带内的灰岩外来体时代集中在瓜德鲁普世(Guadalupian,中二叠世)中、晚期至早三叠世,古生物地理与喜马拉雅特提斯带有显著差异,最有可能为新特提斯洋中的海山型沉积.基墨里(Cimmerian)微地块群在乌拉尔世(Cisuralian,早二叠世)早期阿瑟尔期-萨克马尔期(Asselian-Sakmarian)全部位于冈瓦纳大陆北缘,均发育冰海相沉积及冈瓦纳型冷水生物群.乌拉尔世中期(约290~280ma)基墨里微地块群由于印度板块北缘Panjal Traps等大火成岩省岩浆活动与冈瓦纳大陆裂解,并以不同的速度向北漂移.可以分为两个条带,由南羌塘、保山和Sibuma地块组成的北基墨里微地块群漂移速度较快,在亚丁斯克期(Artinskian)就已经出现大量碳酸盐岩沉积和暖水生物群,因此,它们最先从冈瓦纳大陆裂解并进入低纬度暖水区域;而由拉萨、腾冲和Irrawaddy地块组成的南基墨里微地块群,漂移速度相对较慢,在空谷(Kungurian)晚期才开始出现大规模碳酸盐岩沉积,并延续至乐平世(Lopingian,晚二叠世),瓜德鲁普世和乐平世地层中含暖水生物为主的动物群,因此,这些地块至少在空谷晚期已经从冈瓦纳大陆北缘分离,裂解时间稍晚于北基墨里微地块群;这种沉积和古生物地理的时空演变差异性表明乌拉尔世的裂解事件造成了中特提斯洋和新特提斯洋的开启和形成.更北的北羌塘地块由于整个二叠纪地层中均含有典型的暖水生物群,与华南地区、思茅地块和印支地块等可以比较,属于古特提斯洋北部的块体.因此,二叠纪中、晚期特提斯域形成了古、中、新特提斯多岛洋共存的局面,是当时构造活动最活跃的地区和全球生物多样性的中心.此外,青藏高原多个块体在二叠纪位于南半球中高纬度地区,完整记录了晚古生代大冰期、亚丁斯克期全球变暖和二叠纪末快速变暖等重大古气候事件,对于阐明板块运动和全球气候演变对生物群时空分布的影响具有举足轻重的作用.

关键词：二叠纪特提斯洋青藏高原生物群古地理

A theoretical study on different cluster configurations of the ~9Be nucleus by using a simple cluster model

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Nuclear Science and Techniques 2017年第6期28卷 179-189页

作者： m.Aygun z.Aygun Department of Physics Bitlis Eren University Vocational School of Technical Sciences Bitlis Eren University

In this study,a comprehensive investigation on different cluster configurations of the ~9Be nucleus is performed with a simple cluster *** this goal,the elastic scattering angular distributions of ~9Be by ^(27)A1,^(28)Si,^(64)zn,^(144)Sm,^(208)Pb,and ^(209)Bi target nuclei are reanalyzed for α + α + n,d + ~7Li,~3H + ~6Li,~3He + ~6He and n + ~8Be cluster configurations of the ~9Be projectile within the framework of the optical *** theoretical results are compared with each other as well as the experimental *** results provide an opportunity for a test of different cluster configurations in explaining the elastic scattering of^9Be nucleus.

关键词： Cluster structure Optical model Double folding model Elastic scattering

前言:青藏高原及其周边综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 911-914页

作者：沈树忠丁林朱茂炎王向东邓涛南京大学地球科学与工程学院关键地球物质循环前沿科学中心内生金属成矿机制研究国家重点实验室南京210023 中国科学院青藏高原研究所青藏高原地球系统全国重点实验室北京100101 中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学地球与行星科学学院北京100049 中国科学院古脊椎动物与古人类研究所中国科学院脊椎动物演化与人类起源重点实验室北京100044

青藏高原研究对揭示地史时期全球构造、古地理、生物与环境等的演化都具有举足轻重的作用.文章介绍了“青藏高原及其周边综合地层、生物群与古地理演化”专辑的组织背景、主要内容和期望目标,同时总结了本专辑成果相比第一次青藏高原科... 详细信息

青藏高原研究对揭示地史时期全球构造、古地理、生物与环境等的演化都具有举足轻重的作用.文章介绍了“青藏高原及其周边综合地层、生物群与古地理演化”专辑的组织背景、主要内容和期望目标,同时总结了本专辑成果相比第一次青藏高原科考报告的显著进展.

关键词：期望目标生物群全球构造生物与环境青藏高原周边

EFFECT OF GRAIN REFINING ON PRImARYαPHASE IN SEmI-SOLID A356 ALLOY PREPARED BY LOW SUPERHEAT POURING AND SLIGHT ELECTROmAGNETIC STIRRING

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Acta metallurgica Sinica(English Letters) 2008年第1期21卷 57-64页

作者： z. Liu W.m. mao z.D. zhao Faculty of material and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China School of material Science and Engineering University of Science ＆ Technology Beijing Beijing 100083 China

The semi-solid slurry of A356 alloy, which is grain-refined by Al-Ti-B master alloy, is prepared by low superheat pouring and slight electromagnetic stirring. The effects of grain refining on the morphology and the grain size of the primary α phase in the slurry manufactured are researched. The results indicate that the slurry with particle-like and rosette-like primary α phases can be prepared by low superheat pouring and slight electromagnetic stirring from liquid A356 alloy grain-refined, in which the pouring temperature can be suitably raised. Compared with the A356 samples without grain refining, the grain size and particle morphology of primary α phase as well as the distribution of the grain with particle-like or rosette-like along radial in the ingot in A356 are markedly improved by grain refining.

关键词： Semi-solid Grain-refined Low superheat pouring Slight electromagnetic stirring A356 alloy Al-Ti-B