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Observation of spectral lines in the exceptional GRB 221009A

Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu Zhang Shao-Lin xiong Ji-Rong Mao Shuang-Nan Zhang wang-Chen Xue Chao Zheng Jia-Cong Liu Zhen Zhang xi-lu wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song Zheng-Hua An Ce Cai xin-Qiao Li Wen-xi Peng Wen-Jun Tan Chen-Wei wang xiang-Yang Wen Yue wang Shuo xiao Fan Zhang Peng Zhang Shi-Jie Zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line

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Liquid metal biomaterials: translational medicines,challenges and perspectives

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National Science Review 2024年第2期11卷 264-284页

作者： Hanchi Xu Jincheng lu Yikuang xi Xuelin wang Jing Liu Department of Biomedical Engineering School of Medicine Tsinghua University Beijing Tsinghua Changgung Hospital School of Clinical Medicine Tsinghua University Shanghai World Foreign Language Academy Beijing Advanced Innovation Center for Biomedical Engineering School of Engineering MedicineBeihang University Beijing Key Lab of Cryo-Biomedical Engineering and Key Lab of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Until now, significant healthcare challenges and growing urgent clinical requirements remain incompletely addressed by presently available biomedical materials. This is due to their inadequate mechanical compatibility, suboptimal physical and chemical properties, susceptibility to immune rejection, and concerns about long-term biological safety. As an alternative, liquid metal(LM) opens up a promising class of biomaterials with unique advantages like biocompatibility, flexibility, excellent electrical conductivity,and ease of functionalization. However, despite the unique advantages and successful explorations of LM in biomedical fields, widespread clinical translations and applications of LM-based medical products remain limited. This article summarizes the current status and future prospects of LM biomaterials, interprets their applications in healthcare, medical imaging, bone repair, nerve interface, and tumor therapy, *** to translate LM materials into medicine and obstacles encountered in practices are *** that, we outline a blueprint for LM clinics, emphasizing their potential in making new-generation artificial organs. Last, the core challenges of LM biomaterials in clinical translation, including bio-safety,material stability, and ethical concerns are also discussed. Overall, the current progress, translational medicine bottlenecks, and perspectives of LM biomaterials signify their immense potential to drive future medical breakthroughs and thus open up novel avenues for upcoming clinical practices.

关键词： liquid metal biomaterials translational medicine clinical device healthcare therapeutics

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Stereoselective Synthesis of (6R)-6-(5-Methyl-2-furyl)-2-oxocyclohexanecarboxyl-10', 2'-Sultam

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Chinese Chemical Letters 1999年第9期10卷 733-734页

作者： xi lu wang You Hong HU Li Gong OU Dong lu BAI(Shanghai Institute of Materia Medica. Chinese Academy of Sciences, Shanghai 200031) Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

Stereoselective synthesis of sultam 8 was reported. The overall yield in a scLluence of 4steps is 27.5%.

关键词： Stcreoselective. synthesis. sultam. conjugated addition.

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Relationship between Natural Fracture and Structural Style and its Implication for Tight Gas Enrichment:A Case Study of Deep Ahe Formation in the Dibei–Tuzi Area,Kuqa Depression

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 1086-1110页

作者： xiA lu xi Kelai YANG xianzhang HAN Zhanghua XU Zhenping ZHOU lu YU Guoding wang Daoshen wang Weiyu School of Petroleum Engineering Shandong Institute of Petroleum and Chemical TechnologyDongyingShandong 257061China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong 266580China Research Institute of Petroleum Exploration and Development PetroChina Tarim Oilfield CompanyKorlaXinjiang 841000China

The deep Lower Jurassic Ahe Formation(J_(1a))in the Dibei–Tuzi area of the Kuqa Depression has not been extensively explored because of the complex distribution of fractures.A study was conducted to investigate the relationship between the natural fracture distribution and structural *** J_(1a)fractures in this area were mainly high-angle shear fractures.A backward thrust structure(BTS)is favorable for gas migration and accumulation,probably because natural fractures are more developed in the middle and upper parts of a thick competent *** opposing thrust structure(OTS)was strongly compressed,and the natural fractures in the middle and lower parts of the thick competent layer around the fault were more *** vertical fracture distribution in the thick competent layers of an imbricate-thrust structure(ITS)differs from that of BTS and *** intensity of the fractures in the ITS anticline is similar to that in the *** density in monoclinic strata in a ITS is controlled by ***,the structural style controls the configuration of faults and anticlines,and the stress on the competent layers,which significantly affects deep gas reservoir *** enrichment of deep tight sandstone gas is likely controlled by two closely spaced faults and a fault-related anticline.

关键词： fracture distribution structural style deep tight sandstone electrical image logging Kuqa Depression Tarim Basin

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Assessing the performance of magnetopause models based on THEMIS data

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Earth and Planetary Physics 2024年第5期8卷 776-786页

作者： Yang Lin JianYong lu BaoHang Qu xi wang Institute of Space Weather School of Atmospheric PhysicsNanjing University of Information Science & Technology

The magnetopause is the boundary between the Earth's magnetic field and the interplanetary magnetic field（IMF）,located where the supersonic solar wind and magnetospheric pressure are in *** empirical models and global magnetohydrodynamic simulations have been used to define the magnetopause,each of these has *** this work,we use15 years of magnetopause crossing data from the THEMIS（Time History of Events and Macroscale Interactions during Substorms）spacecraft and their corresponding solar wind parameters to investigate under which solar wind conditions these models predict more *** analyze the pattern of large errors in the extensively used magnetopause model and show the specific solar wind parameters,such as components of the IMF,density,velocity,temperature,and others that produce these *** is shown that（1） the model error increases notably with increasing solar wind velocity,decreasing proton density,and increasing temperature;（2） when the cone angle becomes smaller or|Bx|is larger,the Shue98 model errors increase,which might be caused by the magnetic reconnection on the dayside magnetopause;（3） when|By|is large,the error of the model is large,which may be caused by the east–west asymmetry of the magnetopause due to magnetic reconnection;（4） when Bzis southward,the error of the model is larger;and（5） the error is larger for positive dipole tilt than for negative dipole tilt and increases with an increasing dipole tilt ***,the global simulation model b Liu ZQ et al.（2015） shows a substantial improvement in prediction accuracy when IMF Bx,By,or the dipole tilt cannot be *** result can help us choose a more accurate model for forecasting the magnetopause under different solar wind conditions.

关键词： magnetopause empirical model global magnetohydrodynamic simulation THEMIS solar wind parameters

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Synthesis of Anti-Pancreatic Cancer Natural Product Majusculamide D and Analogues Reveals a Preliminary Structure-Activity Relationships

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Chinese Journal of Chemistry 2024年第6期42卷 605-610页

作者： xiuhe Zhao Mengxue Lv xiaonan xi Yaxin lu Liang wang Yue Chen The State Key Laboratory of Medicinal Chemical Biology College of PharmacyNankai UniversityTianjin300350 China College of Chemistry Nankai UniversityTianjin300071 China

The total synthesis of majusculamide D(1)was achieved from commercially available *** addition,we synthesized eight analogues including three stereoisomers of majusculamide D that differ in the fatty acid *** analogues including a simplified analogue 29 exhibited significant nanomolar-level IC50 values against Panc-1 cells in MTT assays.A preliminary SAR analysis indicated that the hydroxyl group at C10 and C2−C3 unsaturated double bond of majusculamide D were essential in maintaining the high activity against Panc-1 cells and the orientation of C40-Me and C42-Me groups was tolerable.

关键词： Majusculamide D Natural products SAR Anti-pancreatic cancer Lipopentapeptide

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Studies on the Total Synthesis of Pseudolaric Acid A Stereocontrolled Synthesis of the Seven-membered Lactone

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Chinese Chemical Letters 1999年第4期10卷 281-284页

作者： You Hong HU Li Gong OU xi lu wang Dong lu BAI(Shanghai Institute of Materia Medica,Chinese Academy of Sciences. 294 Taiyuan Road, Shanghai 200031) Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

The lactone 16 was obtained stereo- and regioselectively by a reaction sequence of 9 steps in 21% overall yield.

关键词： Pseudolaric acid A stereocontrol synthesis seven-membered lactone

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Dynamic recrystallization behavior and strengthening mechanism of a novel Mo-Ti_(3)AlC_(2) alloy at ultrahigh temperature

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Rare Metals 2024年第8期43卷 3946-3960页

作者： lu Yang xin-Yuan Zheng Yang Zhao xi-Ran wang Fang-Nao xiao Shi-Zhong Wei School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and TechnologyLuoyang 471003China Department of Applied Mechanics Univ.Bourgogne FrancheComteFEMTO-ST InstituteCNRS/UF/ENSMM/UTBM25000BesangonFrance

Increasing the recrystallization temperature to achieve better high-temperature performance is critical in the development of molybdenum alloys for ultrahightemperature applications,such as the newest generation of multitype high-temperature nuclear *** this study,an innovative strategy was proposed to improve the performance of molybdenum alloys at high temperature by using the two-dimensional MAX(where M is an early transition metal,A is an A-group element and X is C or N)ceramic material Ti_(3)AlC_(2).The relationships between flow stress,strain rate and temperature were *** microstructure,distribution of misorientation and evolution of dislocations in the Mo-Ti_(3)AlC_(2) alloy were *** microscopic mechanism of the Ti_(3)AlC_(2) phase in the molybdenum alloy at high temperatures was *** experimental results showed that the peak flow stress of Mo-Ti_(3)AlC_(2) at 1600℃ reached 155 MPa,which was161.8% greater than that of pure *** activation energy of thermal deformation of Mo-Ti_(3)AlC_(2) was as large as537 kJ·mol~(-1),which was 17.6% more than that of pure *** recrystallization temperature reached 1600℃ or even *** topological reaction of the Ti_(3)AlC_(2) phase consumed a large amount of energy at high temperatures,resulting in increases in the deformation activation *** structures of AlTi_3 and Ti-O Magneli-phase oxides(Ti_nO_(2n-1)) were formed in-situ,which relied on kink bands and interlayer slip,resulting in many dislocations during ***,the special two-dimensional of the structure Ti_(3)AlC_(2) ceramic inhibited the recrystallization behavior of the Mo *** results of this study can provide theoretical guidance for the development of a new generation of molybdenum alloys for use in ultrahigh-temperature environments.

关键词： Mo alloy Two-dimensional reinforcement Dynamic recrystallization behavior Hot deformation Mechanical properties

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Impact of thoracic paravertebral block and sufentanil on outcomes and postoperative cognitive dysfunction in thoracoscopic lung cancer surgery

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World Journal of Psychiatry 2024年第6期14卷 894-903页

作者： Dan-Dan wang Hong-Yu wang Yan Zhu xi-Hua lu Department of Anesthesiology The Affiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalZhengzhou 450008Henan ProvinceChina

BACKGROUND Postoperative pain management and cognitive function preservation are crucial for patients undergoing thoracoscopic surgery for lung cancer(LC).This is achieved using either a thoracic paravertebral block(TPVB)or sufentanil(SUF)-based multimodal ***,the efficacy and impact of their combined use on postoperative pain and postoperative cognitive dysfunction(POCD)remain *** To explore the analgesic effect and the influence on POCD of TPVB combined with SUF-based multimodal analgesia in patients undergoing thoracoscopic radical resection for LC to help optimize postoperative pain management and improve patient *** This retrospective analysis included 107 patients undergoing thoracoscopic radical resection for LC at The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital between May 2021 and January *** receiving SUF-based multimodal analgesia(n=50)and patients receiving TPVB+SUF-based multimodal analgesia(n=57)were assigned to the control group and TPVB group,*** compared the Ramsay Sedation Scale and visual analog scale(VAS)scores at rest and with cough between the two groups at 2,12,and 24 h after *** levels of epinephrine(E),angio-tensin Ⅱ(Ang Ⅱ),norepinephrine(NE),superoxide dismutase(SOD),vascular endothelial growth factor(VEGF),transforming growth factor-β1(TGF-β1),tumor necrosis factor-α(TNF-α),and S-100 calcium-binding proteinβ(S-100β)were measured before and 24 h after *** Mini-Mental State Examination(MMSE)was administered 1 day before surgery and at 3 and 5 days after surgery,and the occurrence of POCD was monitored for 5 days after *** reactions were also *** There were no significant time point,between-group,and interaction effects in Ramsay sedation scores between the two groups(P>0.05).Significantly,there were notable time point effects,between-group differences,and interaction effects observed in VAS scores both at rest

关键词： Thoracic paravertebral block Sufentanil Thoracoscope Radical resection of lung cancer Postoperative cognitive dysfunction

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A state-of-the-art review of the development of self-healing concrete for resilient infrastructure

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 151-169页

作者： Dong lu xi JIANG Yao ZHANG Shaowei ZHANG Guoyang lu Zhen LENG Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Laboratory of Fire Safety School of Safety Engineering and Emergency ManagementShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China

The brittleness of cement composites makes cracks almost inevitable,producing a serious limitation on the lifespan,resilience,and safety of concrete *** address this brittleness,self-healing concrete has been developed for regaining its mechanical and durability properties after becoming cracked,thereby promising sustainable development of concrete *** paper provides a comprehensive review of the latest developments in self-healing *** begins by summarizing the methods used to evaluate the self-healing efficiency of ***,it compares strategies for achieving healing *** then discusses the typical approaches for developing self-healing ***,critical insights are proposed to guide future studies on the development of novel self-healing *** review will be useful for researchers and practitioners interested in the field of self-healing concrete and its potential to improve the durability,resilience,and safety of concrete infrastructure.

关键词： resilient infrastructure sustainable concrete self-healing cracks

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