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Research on two-proton radioactivity in density-dependent cluster model

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Science China(Physics,Mechanics & Astronomy) 2023年第2期66卷 59-67页

作者： Ziyi Yuan Dong Bai Zhen Wang Zhongzhou Ren dongdong ni School of Physics Scienceand Engineering Tongji UniversityShanghai 200092China Collegeof Science Hohai UniversityNanjing211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 9078China

The density-dependent cluster model(DDCM) provides a unified framework to study α decay,heavy-cluster radioactivity,and proton emission.Two-proton(2p) radioactivity is a rare decay mode of exotic nuclei near or beyond the drip-line.It is of great interest to explore the applicability of DDCM to this exotic decay mode.In this work,DDCM has been extended to study 2p radioactivity.The 2p-radioactivity half-lives are calculated for several known 2p-emitters,including19Mg,45Fe,48ni,54Zn,and67Kr.The theoretical results are in good agreement with the experimental data,with the standard deviations comparable to or smaller than those given by some other theoretical models and empirical formulas.We also predict the half-lives of a number of possible 2p-emitters with S2p 0 using the new data from AME2020 and NUBASE2020.These predictions serve as useful references for future experimental and theoretical investigations on 2p radioactivity.

关键词： cluster radioactivity decay

Signature of helium rain and dilute cores in Jupiter’s interior from empirical equations of state

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Earth and Planetary Physics 2020年第2期4卷 111-119页

作者： dongdong ni State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and Technology Institute for Planets and Exoplanets University of California

Measurements of Jupiter’s gravity field by Juno have been acquired with unprecedented precision, but uncertainties in the planet’s hydrogen–helium equation of state(EOS) and the hydrogen–helium phase separation have meant that differences remain in the interior model predictions. We deduce an empirical EOS from Juno gravity field observations in terms of the hydrostatic equation and then investigate the structure and composition of Jupiter by comparison of the empirical EOS with Jupiter’s adiabats obtained from the physical EOS. The deduced helium mass fraction suggests depletion of helium in the outermost atmosphere and helium concentration in the inner molecular hydrogen region, which is a signature of helium rain in Jupiter’s interior. The deduced envelope metallicity(the heavy-element mass fraction) is as high in the innermost envelope as 11–13 times the solar value. Such a high metallicity provides sharp support to the dilute core model with the heavy elements dissolved in hydrogen and expanded outward. No matter how the core mass is varied, the empirical EOS derived from the two-layer interior model generally suggests higher densities in the innermost envelope than does the best-fit Jupiter’s adiabat;this result is, again, a signature of dilute cores in Jupiter’s interior. Moreover, no matter the core mass,the empirical EOS is found to exhibit an inflexion point in the deep interior, around 10 Mbar, which can be explained as the combined effect of helium concentration in the upper part and dilute cores in the lower part.

关键词： Jupiter,interior abundances,interiors geophysics

Serpentinisation is Required for the Magnetization of the Martian Crust

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Research in Astronomy and Astrophysics 2023年第6期23卷 134-142页

作者： Shuoran Yu dongdong ni State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SARChina

The remnant magnetism in the crust of Martian southern highland is associated with the magnetic sources at an average depth of~32 km.In this work,we investigate the magnetization of Martian crust via 1-D parameterized model for the stagnant-lid mantle convection.According to our model,the magnetization of Martian crust is likely to take place in the top-down manner during 4.1-3.7 Ga.To reproduce the average depth of magnetic sources below the southern highland,magnetite and Mg-ferrite are anticipated to be the magnetic carriers in the Martian crust,implying the serpentinisation therein.If magnetite is the only magnetic carrier in the Martian crust,the early climate must be warm enough to maintain a surface temperature of 300 K during 4.1-3.7 Ga at least.Such a warm climate is more likely to be a regional phenomenon associated with the serpentinisation in the crust of the southern highland or the hot ejecta of Borialis impact depositing on the southern hemisphere.

关键词： planets and satellites:interiors planets and satellites:magnetic fields planets and satellites:terrestrial planets

Optimal harvesting of a hierarchical age-struetured population system

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International Journal of Biomathematics 2019年第8期12卷 165-189页

作者： Ze-Rong He dongdong ni Shu-Ping Wang Institute of Operational Research and Cybernetics Hangzhou Dianzi University Hangzhou 310018P.R.China

We investigate an optimal harvesting problem for age-structured species,in which elder individuals are more competitive than younger ones,and the population is modeled by a highly nonlinear integro-partial differential equation with a global feedback boundary condition.The existence of optimal strategies is established by means of compactness and maximizing sequences,and the maximum principle obtained via an adjoint system,tangent-normal cones and a new continuity result.In addition,some numerical experiments are presented to show the effects of the price function and younger's weight on the optimal profits.

关键词： Dominance rank population system existence maximum principle numerical method

Calculations of β-decay half-lives of proton-rich nuclei

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Science China(Physics,Mechanics & Astronomy) 2012年第12期55卷 2397-2406页

作者： ni dongdong REN ZhongZhou ZHI QiJun Department of Physics Nanjing UniversityNanjing 210093China Kavli Institute for Theoretical Physics China Beijing 100190China Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion AcceleratorLanzhou 730000China GSI Helmholtzzentrum für Schwerionenforschung DarmstadtGermany School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China

We investigate the half-lives of β + /EC(electron capture) decay using the proton-neutron quasiparticle random-phase approximation(pnQRPA) with a δ-form Gamow-Teller residual interaction.Both particle-hole and particle-particle residual interactions are consistently introduced in dealing with the pnQRPA matrix equation.The sensitivity of the calculated half-lives to some physical quantities used in the calculations is examined.Calculations are performed for even-even neutron-deficient isotopes ranging from Z = 10 to Z = 76.Good agreement between experiment and theory is achieved especially for the nuclei far from stability,and the results of our calculations are discussed with comparison with other theoretical results.Predictions on the β-decay half-lives of some very neutron-deficient nuclei are also given for reference in future experiments.

关键词：计算结果丰质子核半衰期衰变剩余相互作用缺中子同位素准粒子电子捕获

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免用双氧水加工机制丝绵的实验研究

丝绸 2022年第12期59卷 40-45页

作者：黄洁倪冬栋倪学林陈文兴傅雅琴浙江理工大学材料科学与工程学院杭州310018 浙江蚕缘家纺股份有限公司浙江嘉兴314500

由于机制丝绵的劳动生产率高,目前已经成为丝绵生产的主要加工方式,但机制丝绵的加工过程中,一般需要使用双氧水,而双氧水在运输和储存过程中存在易燃易爆等风险。为解决该问题,文章创新性地设计了过碳酸钠或碳酸钠-臭氧联合体系对机制... 详细信息

由于机制丝绵的劳动生产率高,目前已经成为丝绵生产的主要加工方式,但机制丝绵的加工过程中,一般需要使用双氧水,而双氧水在运输和储存过程中存在易燃易爆等风险。为解决该问题,文章创新性地设计了过碳酸钠或碳酸钠-臭氧联合体系对机制丝绵片脱胶的方法,对两种方法的残胶率、含杂率、压缩率和回复率等丝绵质量指标进行分析,并与使用双氧水加工的商业化优等机制丝绵进行比较。研究表明:在机制丝绵加工过程中,使用过碳酸钠或碳酸钠-臭氧加工得到的丝绵脱胶均匀、纤维表面平整光滑;在残胶率、含杂率、压缩回弹性等方面均达到优等品标准(即残胶率≤5%,含杂率≤0.1%,压缩率≥45%,回复率≥92%);在白度和手感柔软性方面也展现出良好的性能。结果表明:在不用双氧水的条件下,依然可以制备性能优良的机制丝绵,显示了免用双氧水加工机制丝绵的可行性。

关键词：机制丝绵脱胶双氧水过碳酸钠碳酸钠-臭氧

Additive manufacturing of niTi lightweight porous structures bio-mimicking coral skeleton with enhanced mechanical properties and shape memory functions

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Science China Technological Sciences 2024年

作者： LIU Xin GU dongdong YUAN LuHao ZHANG Han SUN JianFeng CHEN WenXin WANG Jie SHI KeYu Jiangsu Provincial Research Center for Laser Additive Manufacturing of High-Performance Components College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics

Concerning the high demand for lightweight and multifunctional properties of engineering structures, the coral skeleton-inspired sheet-based(CSS) structure, which was a novel bio-mimicking coral skeleton wall-septa architecture with a unique ability to resist wave shocks was fabricated using niTi alloy by laser powder bed fusion(LPBF) technology. The effects of laser energy density(LED) on surface morphologies, microstructures, phase transformation behavior, and mechanical properties of LPBFfabricated CSS structures were systematically investigated. The results indicated that the size deviation was predominantly governed by powder adhesion and step effect. niTi CSS structures with LED of 71 J·mm-3possessed superior compressive modulus(～400 MPa), ultimate strength(～13 MPa), and energy absorption efficiency(～69%). The compression fracture mechanism of the LPBF-fabricated niTi CSS structures was revealed to be predominantly brittle fracture accompanied by ductile fracture. Furthermore, the ni4Ti3nanoprecipitates induced the precipitation strengthening effect, enabling better shape memory response at LED of 71 J·mm-3, with a recoverable strain of 3.63% and recovery ratio of 90.8%, after heating under a pre-strain of4%. This study highlights the importance of a bionic design strategy for enhancing the mechanical properties of niTi components and offers the possibility to tailor its functional properties.

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沉默调节蛋白6对胶质母细胞瘤抑制机制

中华肿瘤防治杂志 2023年第13期30卷 773-781页

作者：倪冬冬凌园果龙妮娅姜利时滕炜杨宇石出良钊贵州医科大学神经外科贵州贵阳550000

目的探讨沉默调节蛋白6(SIRT6)在胶质母细胞瘤(GBM)疾病进展中的作用。方法将GBM细胞U87MG分为2组,分别在常氧和缺氧条件下培养,蛋白质印迹法分析SIRT6表达。采用慢病毒感染分别构建SIRT6过表达及沉默的U87MG细胞,CCK-8实验检测过表... 详细信息

目的探讨沉默调节蛋白6(SIRT6)在胶质母细胞瘤(GBM)疾病进展中的作用。方法将GBM细胞U87MG分为2组,分别在常氧和缺氧条件下培养,蛋白质印迹法分析SIRT6表达。采用慢病毒感染分别构建SIRT6过表达及沉默的U87MG细胞,CCK-8实验检测过表达和沉默SIRT6后U87MG细胞活性的变化,并用蛋白质印迹法检测对糖酵解途径的影响。最后,在SIRT6过表达及沉默的U87MG细胞中加入替莫唑胺(TMZ),CCK-8实验检测过表达和沉默SIRT6的U87MG细胞对TMZ的药物敏感性,蛋白质印迹检测蛋白表达的变化,流式细胞仪检测细胞凋亡水平。结果缺氧实验:与常氧组细胞比较,缺氧组SIRT6受到抑制,差异有统计学意义,t=11.920,P=0.000 3;而诱导转录因子1α(HIF1α;t=9.888,P=0.000 6)、乳酸脱氢酶(LDHA;t=11.890,P=0.000 3)、肌肉丙酮酸激酶同工酶2(PKM2;t=12.060,P=0.000 3)及葡萄糖转运体1(GLUT1;t=18.190,P<0.000 1)蛋白表达水平上调。细胞活性和糖酵解实验:同OE-NC组比较,OE-SIRT6组细胞活性在第5(t=4.869,P=0.008 2)和7天(t=6.197,P=0.003 4)被抑制;同sh-NC组比较,sh-SIRT6组细胞活性在第5(t=3.066,P=0.037 5)和7天(t=5.017,P=0.007 4)被上调。蛋白质印迹检测结果显示,与OE-NC组比较,OE-SIRT6组抑制HIF1α(P=0.000 3)、LDHA(P<0.000 1)、PKM2(P=0.010 6)和GLUT1(P=0.001 2)蛋白表达;与sh-NC组比较,沉默sh-SIRT6能够上调HIF1α(P<0.000 1)、LDHA(P<0.000 1)、PKM2(P<0.000 1)和GLUT1(P<0.000 1)蛋白表达。OE-SIRT6组细胞葡萄糖摄取量为(0.82±0.21) mmol/g,乳酸产生水平为(0.12±0.03) mmol/g,均低于OE-NC组,P=0.009 0。与sh-NC组比较,sh-SIRT6组细胞的葡萄糖摄取量为(1.34±0.10) mmol/g,乳酸分泌水平为(0.46±0.05) mmol/g,均上调,均P<0.000 1。药物敏感性实验:CCK8实验结果显示,缺氧条件能够上调U87MG细胞在TMZ药物压力下的细胞活性,P=0.013 2。在缺氧背景下,同TMZ组比,过表达SIRT6能够增强TMZ对U87MG细胞的抑制作用,P=0.000 5;而沉默SIRT6能上调细胞对TMZ的抗性作用,P<0.000 1。流式细胞术检测结果表明,同TMZ组(8.59±0.69)%比,OE-SIRT6+TMZ组细胞凋亡率(18.0±2.15)%上调,P=0.002 0;而sh-SIRT6+TMZ组U87MG细胞的凋亡率(1.69±0.96)%下降,P=0.000 5。结论 SIRT6可以通过HIF1α/糖酵解途径抑制GBM U87MG的增殖,促进其凋亡并增强缺氧状态下GBM U87MG对TMZ的药物敏感性,发挥抑癌作用。

关键词：沉默调节蛋白6 缺氧糖酵解胶质母细胞瘤细胞增殖替莫唑胺耐药

Mechanism of K/ni Etching for Biochar-H_(2)O Gasification

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Journal of Harbin Institute of Technology(New Series) 2024年第3期31卷 1-18页

作者： Zhenyu Cheng dongdong Feng Qi Shang Yijun Zhao Wenda Zhang Shaozeng Sun School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Biomass-H_(2)O gasification is a complex thermochemical reaction,including three processes of volatile removal:homogeneous/heterogeneous reforming,biochar gasification and etching.The rate-determining step is biochar-H_(2)O gasification and etching so the DFT is carried out to see the catalytic role of different metal elements(K/ni)in the zigzag biochar model.The calculation results show that the gasification of biochar-H_(2)O needs to go through four processes:dissociative adsorption of water,hydrogen transfer(hydrogen desorption,hydrogen atom transfer),carbon dissolution and CO desorption.The energy barrier indicated that the most significant step in reducing the activation energy of K is reflected in the hydrogen transfer step,which is reduced from 374.14 kJ/mol to 152.41 kJ/mol;the catalytic effect of ni is mainly reflected in the carbon dissolution step,which is reduced from 122.34 kJ/mol to 84.8 kJ/mol.The existence of K causes the edge to have a stronger attraction to H and does not destroy theπbonds of biochar molecules.The destruction ofπbonds is mainly due to the role of H free radicals,while the destruction ofπbonds will lead to easier C-C bond rupture.ni shows a strong attraction to O in OH,which forms strong ni-O chemical bonds.ni can also destroy the aromatic structure directly,making the gasification easier to happen.This study explored the catalytic mechanism of K/ni on the biochar-H_(2)O gasification at the molecular level and looked forward to the potential synergy of K/ni,laying a foundation for experimental research and catalyst design.

关键词： Biochar Potassium-nickel catalysis H_(2)O gasification etching Quantum chemistry Transition state theory

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