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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao zhang Yu-Hai zhang Ying Zou Xiu-Xiu Yang Gen zhang Feng-Shou zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

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Degradable magnesium alloy suture promotes fibrocartilaginous interface regeneration in a rat rotator cuff transosseous repair model

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Journal of Magnesium and Alloys 2024年第1期12卷 384-393页

作者： Baoxiang zhang Wen zhang Fei zhang Chao Ning Mingyang An Ke Yang Lili Tan Qiang zhang Department of Sports Medicine Chinese PLA General HospitalBeijing 100853China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Medical School of PLA Beijing 100853China Institute of Orthopedics Chinese PLA General HospitalBeijing Key Lab of Regenerative Medicine in OrthopedicsKey Lab of Musculoskeletal Trauma&War Injuries of Chinese PLABeijing 100853China

Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional *** the present work,degradable magnesium(Mg)alloy wire was applied to suture supraspinatus tendon in a rat acute rotator cuff tear model with Vicryl Plus 4±0 absorbable suture as *** shoulder joint humerus-supraspinatus tendon complex specimens were retrieved at 4,8,and 12 weeks after *** Mg alloy suture groups showed better biomechanical properties in terms of ultimate load to *** observation showed that hyperplastic response of the scar tissue at the tendon-bone interface is progressively alleviated over time in the both Mg alloy suture and Vicryl suture *** the histological analysis,for Mg alloy suture groups,chondrocytes appear to proliferate at 4 weeks postoperatively,and the tendon-bone interface showed an orderly structural transition zone at 8 weeks *** collagenous fiber tended to be aligned and the tendon-bone interlocking structures apparently formed,where transitional structure from unmineralized fibrocartilage to mineralized fibrocartilage was closer to the native fibrocartilaginous *** vivo degradation of the magnesium alloy wire was completed within 12 *** results indicated that Mg alloy wire was promising as degradable suture with the potential to promotes fibrocartilaginous interface regeneration in rotator cuff repair.

关键词： Rotator cuff repair Mg alloy wire Tendon-bone healing Fibrocartilaginous interface

β-decay study of neutron-rich nucleus ^(34)Al

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Science China(Physics,Mechanics & Astronomy) 2017年第4期60卷 69-73页

作者： Rui Han XiangQing Li WeiGuang Jiang ZhiHuan Li Hui Hua shuangquan zhang CenXi Yuan DongXing Jiang YanLin Ye Jing Li ZongHao Li FuRong Xu QiBo Chen Jie Meng JianSong Wang Chuan Xu YeLei Sun ChunGuang Wang HongYi Wu ChenYang Niu ChenGuang Li Chao He Wei Jiang PengJie Li HongLiang Zang Jun Feng SiDong Chen Qiang Liu XiaoChi Chen HuShan Xu ZhengGuo Hu YanYun Yang Peng Ma JunBing Ma ShiLun Jin Zhen Bai MeiRong Huang Yuan Jie Zhou WeiHu Ma Yong Li XiaoHong Zhou YuHu zhang GuoQing Xiao WenLong Zhan School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen University Institute of Modern Physics Chinese Academy of Sciences

The ＂island of inversion＂ has been known for over a quar- ter century, since Warburton et al. [1] proposed that nuclei with intruder ground states would constitute a 3x3 square with Z=10-12, N=20-22 in 1990. Uncovering the underlying inversion mechanism and exploring the scope of the island have attracted significant theoretical and experimental efforts in the following years. Now it is well known that the reduction of N=20 shell gap, which is likely caused by the strong nucleon-nucleon tensor interaction [2-5], allows the intrusion of neutron orbits from the pf shell into the sd shell and results in the inversion of the 2p-2h intruder and 0p-0h normal con- figurations of the nuclear ground states in this region. Mean- while, the original border of the ＂island of inversion＂ has been extended greatly [6-14].

关键词： Al decay study of neutron-rich nucleus

A-60和A-80质量区原子核磁转动研究进展

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科学通报 2023年第9期68卷 1082-1089页

作者：罗迪雯徐川吴鸿毅张双全李湘庆李智焕华辉北京大学物理学院核物理与核技术国家重点实验室北京100871

近年来,人们在很多原子核中发现了具有强M1跃迁、较弱E2跃迁的磁转动结构,这已经成为原子核高自旋态的研究热点.通过在束γ谱学实验,北京大学实验核物理研究组在中国原子能科学研究院HI-13串列加速器和南非iThemba国家实验室回旋加速器... 详细信息

近年来,人们在很多原子核中发现了具有强M1跃迁、较弱E2跃迁的磁转动结构,这已经成为原子核高自旋态的研究热点.通过在束γ谱学实验,北京大学实验核物理研究组在中国原子能科学研究院HI-13串列加速器和南非iThemba国家实验室回旋加速器上先后开展了对A-80和A-60质量区原子核磁转动结构的研究.在^(75)As、^(79)Se和^(62)Cu核中发现了高激发磁偶极带结构,利用基于协变密度泛函理论的倾斜轴推转模型分析了它们的结构特点.研究表明,^(75)As和^(79)Se核中磁偶极带的角动量形成机制不同于传统的磁转动剪刀机制,随着转动频率的增加,它们只有中子角动量J_(ν)向总角动量方向出现了较大角度的闭合,而质子角动量J_(π)基本上保持不动,总角动量的倾斜角出现了一个较大的变化(向x轴方向闭合).这种只有一个剪刀片闭合的角动量形成机制被形象地称为订书机机制.

关键词：在束γ谱学磁转动订书机带协变密度泛函理论倾斜轴推转模型

Road map for, and technical challenges of, carbon-nanotube integrated circuit technology

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National Science Review 2024年第3期11卷 14-16页

作者： Jia Si Panpan zhang Zhiyong zhang Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics School of Electronics Peking University State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

The past decade has witnessed an explosion of research on carbon-nanotube(CNT) electronics due to their outstanding properties, including an ultrathin body, a high carrier mobility and a high saturation velocity.

关键词： TRANSISTORS

周口店第一地点第4-5层脉石英原料产地分析

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第四纪研究 2011年第5期31卷 900-908页

作者：李锋王春雪刘德成张晓凌张双权高星中国科学院占脊椎动物与古人类研究所人类演化实验室北京100044 中国科学院研究生院北京100049 吉林大学边疆考古研究中心长春130012

文章从考古学角度对遗址周围潜在原料产地进行调查,并以遗址出土文化遗物最为丰富的第4～5层为例对其原料采集策略进行初步分析。调查显示,遗址以北、周口河两岸的石炭-二叠系地层和花岗岩侵入体中多有石英脉出露,而遗址以南多为灰岩、... 详细信息

文章从考古学角度对遗址周围潜在原料产地进行调查,并以遗址出土文化遗物最为丰富的第4～5层为例对其原料采集策略进行初步分析。调查显示,遗址以北、周口河两岸的石炭-二叠系地层和花岗岩侵入体中多有石英脉出露,而遗址以南多为灰岩、白云岩山地,少见石英脉出露。遗址第4～5层石制品的原料分析显示,距今30万年左右的"北京人"既从河流砾石层也从岩脉露头或风化处采集脉石英进行石器生产;古人类可能对不同类型脉石英采取多种开发策略;对石英脉的利用具有一定的技术组织性,表现出一副多样的原料开发图景。

关键词：周口店第一地点 4~5层脉石英原料开发方略技术组织性

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： Qing-Ping Li Jin-Ya zhang Jia-Xiang zhang Yong-Xue zhang CNOOC Research Institute Company Limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

～2.7 Ga crust growth in the North China craton

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～2.7 Ga crust growth in the North China craton

Solid Bronsted acidity boosts adsorption reactivity of nano-adsorbent for water decontamination

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Neng Jiang~(a,*),Jinghui Guo~a,Mingguo Zhai~a,shuangquan zhang~b a Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,China b Department of Chemistry and Biochemistry,University of Windsor,ON,Canada

Numerous U-Pb zircon geochronological data show that rocks of the Precambrian basement from the North China craton(NCC)have two age peaks at 1.8-1.9 and～2.5Ga,*** the most prominent peak at～2.5 Ga really registered a period of major crustal growth in the NCC thus making it different from the global major crustal growth period of～2.7 Ga is *** this paper,we carried out in situ U-Pb and Hf isotopes of zircons and whole rock chemical and Sr-Nd isotopic analyses for six Precambrian samples from the NCC in order to understand crustal growth and *** samples have U-Pb zircon ages of 1.8-1.9,～2.5 and～2.7Ga,*** two samples with U-Pb zircon ages of～2.7 Ga have zircon Hf model ages(T)and/or whole rock Nd model ages(T)close to their U-Pb zircon *** is clear that they represent juvenile crust generation,thus providing direct evidence that～2.7 Ga was a period of new crustal *** samples with U-Pb zircon ages of～1.8 and～2.5 Ga also have Tand/or Tsimilar to those of the～2.7 Ga samples,indicating that these samples also have a mantle extraction time of 2.7±0.1 Ga and their～1.8 and～2.5 Ga ages may represent periods of reworking of the 2.7±0.1-Ga crust rather than juvenile crust *** reworking is manifested either as metamorphism or as lower crustal-derived ***,the～2.5-Ga tonalitic gneiss sample is thought to be derived by melting of the～2.7 Ga lower *** many～2.5- Ga tonalite-trondhjemite-granodiorites(TTGs)and calc-alkaline granitoids in the NCC contain～2.7-Ga xenocrystic and inherited zircons,we postulate that they are probably also derived mainly from the 2.7±0.1-Ga *** data imply that the quantity of～2.7 Ga continental crust in the NCC is probably greater in extent than that exposed today.

关键词： Crustal growth Crustal reworking North China craton U-Pb zircon ages Archean TTGs

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 23-34页

作者： Sikai Cheng Zhixian Li Kaisheng zhang Qingrui zhang Xiaolin zhang Bingcai Pan State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Environmental Materials and Pollution Control Laboratory Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Heavy Metal Deep-remediation in Water and Resource Reused Qinhuangdao 066004China Research Center for Environmental Nanotechnology(ReCENT) Nanjing UniversityNanjing 210023China

Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water *** addition,the critical issue of polysilicate scaling that results from the ubiquitous silicates must be *** tackle these issues,an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Bronsted acidity is *** feasibility of this approach is demonstrated by growing zirconium phosphate(ZrP)inside a gel-type anion exchanger,N201,to produce nanocomposite ZrP@N201,in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr^(4+) sites and Bronsted acidic monohydrogen phosphate groups(-O_(3)POH).Compared with the Lewis acidic nano-zirconium oxide analog(HZ0@N201),ZrP@N201 exhibited a greatly improved adsorption capacity(117.9 vs.52.3 mg/g-Zr)and mass transfer rate(3.56×10^(-6) vs.4.55×10^(-7) cm/s),while bulk ZrP produced a thermodynamically stableα-phase with Bronsted acidity that exhibited negligible adsorption capability toward *** enhanced defluoridation activity of ZrP@N201 is attributed to Bronsted acidity and the increased outer electron density of ZA+sites,as corroborated using XPS and solid-state NMR ***,Bronsted acidity strengthens the resistance of ZrP@N201 to silicate,allowing its full regeneration during cyclic *** tests demonstrated 3-10 times the amount of clean water from(waste)for ZrP@N201 as compared to both HZO@N201 and the widely used activated aluminum *** study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.

关键词： Nanocomposite Selective adsorption Fluoride removal Dual Lewis and Bronsted acidity Regeneration