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Production of neutron-rich actinide isotopes in isobaric collisions via multinucleon transfer reactions
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作者 Peng-Hui Chen Chang Geng +2 位作者 Zu-Xing Yang Xiang-Hua Zeng Zhao-Qing Feng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第10期166-177,共12页
We systematically calculated the multinucleon transfer reactions of ^(208)Os,^(208)Pt,^(208)Hg,^(208)Pb,^(208)Po,^(208)Rn,^(208)Ra,and ^(132,136) Xe when bombarded on ^(232) Th and ^(248) Cm at Coulomb barrier energie... We systematically calculated the multinucleon transfer reactions of ^(208)Os,^(208)Pt,^(208)Hg,^(208)Pb,^(208)Po,^(208)Rn,^(208)Ra,and ^(132,136) Xe when bombarded on ^(232) Th and ^(248) Cm at Coulomb barrier energies within the dinuclear system model.These results are in good agreement with the available experimental data.The influence of Coulomb and shell effects on actinide production in these reactions has been rigorously studied.We calculated and analyzed the potential energy surface (PES) and total kinetic energy (TKE) mass distributions for the reactions involving ^(208)Hg,^(208)Pb,and ^(208) Po with ^(248) Cm and ^(232)Th.The PES and TKE spectra shed light on the fragment formation mechanisms in multinucleon transfer reactions,with clear indications of isospin and shell effects.The production cross sections for multinucleon transfer products show a strong dependence on isobar projectiles with a mass number A=208.Isobar projectiles with high N/Z ratios are advantageous for generating neutron-rich target-like fragments.Conversely,products induced by isobar projectiles with larger charge numbers tend to shift toward proton-rich regions.The intertwining of the Coulomb potential and shell effect is evident in the production cross sections of actinide isotopes.Drawing from reactions induced by radioactive projectiles,we anticipate the discovery of several new actinide isotopes near the nuclear drip lines,extending our reach into the superheavy nuclei domain. 展开更多
关键词 Dinuclear system model Isobaric collisions Multinucleon transfer reactions Neutron-rich actinides
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Product polarization and mechanism of Li + HF(v=0, j=0) → LiF(v', j') + H collision reaction 被引量:2
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作者 岳现房 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期275-281,共7页
A state-to-state dynamics analysis for the Li+HF (v = 0, j = 0)→LiF (v’, j’)+H collision reaction has been performed through quasiclassical trajectory (QCT) calculations. It is found that the differential c... A state-to-state dynamics analysis for the Li+HF (v = 0, j = 0)→LiF (v’, j’)+H collision reaction has been performed through quasiclassical trajectory (QCT) calculations. It is found that the differential cross section (DCS) of the LiF products from the title reaction is preferentially backward scattering for v’=0, yet forward scattering for v’=1 and 2. For v’=3, the DCS exhibits forward, backward, and sideways scatterings. The variation of the internuclear distances and angles along the propagation time reveals that more than 99.08% of reaction trajectories undergo the direct reaction mechanism. The values of the polarization parameters a1-{1} and a0{2} demonstrate that the product rotational angular moment j’ is not only aligned perpendicular to the reagent relative velocity vector k, but also oriented along the negative y axis. These product polarization results agree well with the recent quantum mechanical studies. The mechanism of these results was proposed and discussed in detail. 展开更多
关键词 product polarization collision reaction state-to-state resolved differential cross section quasi-classical trajectory
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THEORETICAL INVESTIGATION OF COLLISION ENERGY EFFECT ON REACTION O(?) BARIUM WITH METHYL BROMIDE
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作者 Ke Li HAN Ben Fan SUN Guo Zhong HE State Key Laboratory of Molecular Reaction Dynamics,Dalian Institute of Chemical Physics,Chinese Academy of Science,Dalian 116023 Xi Guang ZHFNG Qin Xing LI Zhen Xin YU Institute for Lasers and Spectroscopy,Zhongshan University,Guangzhou 510275 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第6期513-516,共4页
The reac dynamics on Ba+BrCH_3→BaBr+CH_3 has been investigated in the first proposed potential energy surface of the generalized LEPS type,using the quasiclassical trajectory method.In simulation of the conditions in... The reac dynamics on Ba+BrCH_3→BaBr+CH_3 has been investigated in the first proposed potential energy surface of the generalized LEPS type,using the quasiclassical trajectory method.In simulation of the conditions in molecular beam experiments,the results of the present study show significant effect of the reagent collision energy on the dynamics of the reaction,and are in good agreement with the experimental ones. 展开更多
关键词 BARIUM WITH METHYL BROMIDE THEORETICAL INVESTIGATION OF collision ENERGY EFFECT ON reaction O
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Stereodynamics Study of Li+HF→LiF+H Reactions on X^2A’ Potential Energy Surface at Collision Energies below 5.00 kcal/mol
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作者 李红征 刘新国 +1 位作者 谭瑞山 胡梅 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期52-56,共5页
The product rotational polarizations of reaction Li-SHF→LiF-kH at different collision energies, as well as at the different vibrational states and rotational states, are calculated by using the quasi-classical trajec... The product rotational polarizations of reaction Li-SHF→LiF-kH at different collision energies, as well as at the different vibrational states and rotational states, are calculated by using the quasi-classical trajectory method based on a new potential energy surface constructed by Aguado et al. [J. Chem. Phys. 119(2003) 10088]. We investigate the Mignment and the orientation of the product molecule by calculating the P(θr, φr) distribu- tions describing polar angle distribution, the P(θr) distributions describing the k-j' correlation and the P(φr) distributions describing the k-k'-j' correlation. We also explore the dependence of reaction probabilities and cross sections on the rotational and vibrational quantum number of the title reaction. It is concluded that the vibrational state has more important impact on the angular distribution, reaction probability and cross section. 展开更多
关键词 PES Stereodynamics Study of Li+HF Potential Energy Surface at collision Energies below 5.00 kcal/mol LiF+H reactions on X~2A
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Methodology of Wavelets in Relativistic Heavy Ion Collisions in One Dimensional Phase Space (<i>η</i>-Space) 被引量:1
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作者 Vyacheslav V. Lyashenko M. Ayaz Ahmad +1 位作者 Zhanna V. Deineko Mir Hashim Rasool 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第2期254-266,共13页
An attempt has been made to apply the wavelet methodology for the study of the results of the chaotic behavior of multiparticle production in relativistic heavy ion collisions. We reviewed the data that describes the ... An attempt has been made to apply the wavelet methodology for the study of the results of the chaotic behavior of multiparticle production in relativistic heavy ion collisions. We reviewed the data that describes the collisions of relativistic heavy ion for the case η-space in 1-D phase space of variable. We compared the experimental data and UrQMD data using wavelet coherency. We discussed the results of the comparison. 展开更多
关键词 WAVELET Coherence Morlet WAVELET Heavy Ion collisions reaction Dynamics Phase Space Normalized FACTORIAL MOMENTS
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Rapidity and Pseudorapidity Distributions of theVarious Hadron-Species Produced in High EnergyNuclear Collisions: A Systematic Approach
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作者 Goutam Sau Aparajita Bhattacharya Subrata Bhattacharyya 《Journal of Modern Physics》 2011年第11期1354-1365,共12页
With the help of a phenomenological approach outlined in the text in some detail, we have dealt here with the description of the plots on rapidity and pseudorapidity spectra of some hadron-secondaries produced in vari... With the help of a phenomenological approach outlined in the text in some detail, we have dealt here with the description of the plots on rapidity and pseudorapidity spectra of some hadron-secondaries produced in various nucleus-nucleus interactions at high energies. The agreement between the measured data and the attempted fits are, on the whole, modestly satisfactory excepting a very narrow central region in the vicinity of y = η = 0. At last, hints to how the steps suggested in the main body of the text to proceed with the description of the measured data given in the plots could lead finally to a somewhat systematic methodology have also been made. 展开更多
关键词 Relativistic Heavy Ion collisions INCLUSIVE Cross-Section INCLUSIVE Production with Identified HADRONS QUARKS GLUONS and QCD in Nuclear reactions
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The Fundamental Mechanism for the Collision/Pressure Induced Optic Effect 被引量:1
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作者 Wei-Xing Xu 《Optics and Photonics Journal》 2018年第4期90-97,共8页
In this work, the fundamental mechanism regarding the collision and pressure induced optic effect is elucidated. Based on the concept of the collision-relaxation/the pressure-release induced optic effect put forth her... In this work, the fundamental mechanism regarding the collision and pressure induced optic effect is elucidated. Based on the concept of the collision-relaxation/the pressure-release induced optic effect put forth here, a new laser technology may be developed. Furthermore, our work also makes the understanding the photon involved chemical reaction become much clear and rationalized. 展开更多
关键词 Electro-Optic EFFECT Magnetic-Optic EFFECT Pressure-Optic EFFECT Molecular Beam Technique Laser Technology Chemical reaction Dynamics collision-Induced OPTIC EFFECT PRESSURE-INDUCED OPTIC EFFECT
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ICP-MS/MS测定轻质油中痕量氯含量
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作者 李爱阳 陈宇 +1 位作者 殷子懿 陈林 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第3期813-819,共7页
基于H_(2)反应模式下的质量转移反应消除干扰,建立电感耦合等离子体串联质谱(ICP-MS/MS)测定轻质油中痕量Cl的分析方法。轻质油经简单稀释后直接采用ICP-MS/MS进行测定,在MS/MS模式下使用H_(2)作为反应气,利用在碰撞/反应池(CRC)中Cl^(+... 基于H_(2)反应模式下的质量转移反应消除干扰,建立电感耦合等离子体串联质谱(ICP-MS/MS)测定轻质油中痕量Cl的分析方法。轻质油经简单稀释后直接采用ICP-MS/MS进行测定,在MS/MS模式下使用H_(2)作为反应气,利用在碰撞/反应池(CRC)中Cl^(+)与H_(2)发生二次H原子转移反应形成的子离子(H_(2)Cl^(+))进行测定,消除所有质谱干扰,获得Cl的灵敏度和检出限(LOD)明显优于O_(2)反应模式,LOD低至7.56μg/kg。通过与扇型磁场ICP-MS(SF-ICP-MS)对比分析标准参考物质NIST SRM 1634c,评价方法的准确可靠性。结果表明,标准参考物质的分析结果与认证值基本一致,相对标准偏差(RSD)为3.1%~4.7%,2种方法的对比分析结果在95%的置信度水平无显著性差异。所建立分析方法的灵敏度、准确度和和精密度高,MS/MS模式和H_(2)质量转移法的结合可无干扰测定轻质油中的Cl,适用于轻质油中痕量Cl的质量控制与评估。 展开更多
关键词 轻质油 电感耦合等离子体串联质谱 Cl 碰撞/反应池 H原子转移
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碰撞/反应池电感耦合等离子体质谱(ICP-MS)法测定血液中16种元素
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作者 于宏洋 王萌 +3 位作者 汪冰 王娟 李孟楠 胡克 《中国无机分析化学》 CAS 北大核心 2024年第1期131-138,共8页
采用直接稀释法,使用电感耦合等离子体质谱仪测定血液中元素的过程中,由于血液样本成分复杂,容易产生较大的基体效应,同时一系列多原子离子(例如,^(40)Ar^(16)O^(+)、^(40)Ar^(40)Ar^(+)等)会影响与其有相同质荷比核素的检测,进而影响... 采用直接稀释法,使用电感耦合等离子体质谱仪测定血液中元素的过程中,由于血液样本成分复杂,容易产生较大的基体效应,同时一系列多原子离子(例如,^(40)Ar^(16)O^(+)、^(40)Ar^(40)Ar^(+)等)会影响与其有相同质荷比核素的检测,进而影响测定结果。通过使电感耦合等离子体质谱仪(ICP-MS)分别工作在标准模式、氦气模式和氢气模式下,对比仪器的氧化物离子产率(CeO/Ce)、双电荷离子产率(Ba^(++)/Ba)、灵敏度与检出限情况,同时对氢气模式时仪器上述指标优于其他两种模式的潜在机理进行分析;随后再使用氢气作为碰撞/反应池气体,使用直接稀释法分析全血标准品以及小鼠血液样本中16种元素的含量情况。结果表明,使用氢气作为碰撞/反应池气体时,氧化物离子产率(CeO/Ce)、双电荷离子产率(Ba^(++)/Ba)、灵敏度与检出限情况优于标准模式和氦气模式,且16种元素在0.5~100.0μg/L线性关系良好(R2≥0.99991),对全血标准品中分析准确度为86.0%~114%,分析小鼠血液样本时的加标回收率为81.2%~115%,仪器精密度为2.3%~4.8%,使用氢气作为电感耦合等离子体质谱仪技术的碰撞/反应池气体,为分析血液样品中16种元素(V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ge、As、Se、Cd、Hg、Tl、Pb、Bi)开发一种新的分析方法,也为血液金属组学分析提供了新方法。 展开更多
关键词 电感耦合等离子体质谱仪 碰撞反应池 血液金属组学
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A Trade-off between Solvation and Collision Activation in Steering Competing E2 and S_(N)2 Dynamics
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作者 Hongyi Wang Xu Liu +4 位作者 Siwei Zhao Gang Fu Wenqing Zhen Li Yang Jiaxu Zhang 《Precision Chemistry》 2024年第1期40-48,共9页
The prototypical E2 elimination and SN2 sub-stitution reactions between microsolvated fluoride and ethyl bromide show unexpected dynamic behaviors in mechanistic evolution driven by solvation and collision activation.... The prototypical E2 elimination and SN2 sub-stitution reactions between microsolvated fluoride and ethyl bromide show unexpected dynamic behaviors in mechanistic evolution driven by solvation and collision activation.Considering the steric effects,the gas-phase selectivity favors an E2 pathway barely dependent on collision energies.Remarkably,base solvation steers the reaction in an effective way toward substitution at a near-thermal energy,whereas the governing high-energy events retain elimination.Chemical dynamics simulations reproduce exper-imental findings and uncover a crucial solute-solvent coupling in determining such competing processes.Interestingly,collision activation can tune the underlying atomistic dynamics essentially in the reactant entrance channel and cause a mechanism shift.These features for the ubiquitous competing E2/SN2 dynamics remain quite unknown,providing unique insight into reaction selectivity for complex chemical networks. 展开更多
关键词 E2/S_(N)2 Competition Atomistic Dynamics reaction Mechanisms MICROSOLVATION collision Activation
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微波消解-电感耦合等离子体质谱(ICP-MS)法测定稀释沥青中23种元素
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作者 吴永盛 徐金龙 +3 位作者 曾恒媛 黄武 郑羽茜 庄姜云 《中国无机分析化学》 CAS 北大核心 2024年第4期490-497,共8页
稀释沥青是一种中间产品,主要用于生产沥青。目前测定稀释沥青中元素含量的方法较少,前处理过程繁琐。通过优化样品称样量、消解试剂、赶酸温度,选择合适的前处理方式;通过引入内标元素对非质谱干扰进行校正;通过调谐优化仪器参数,选择... 稀释沥青是一种中间产品,主要用于生产沥青。目前测定稀释沥青中元素含量的方法较少,前处理过程繁琐。通过优化样品称样量、消解试剂、赶酸温度,选择合适的前处理方式;通过引入内标元素对非质谱干扰进行校正;通过调谐优化仪器参数,选择碰撞反应池He模式,采用干扰方程,选择合适同位素等手段对质谱干扰进行了校正;采用45 Sc、72 Ge、115 In、209 Bi作为内标元素,对方法的检出限、精密度、准确度等进行考察,建立了微波消解-电感耦合等离子体质谱法同时测定稀释沥青中铝、钒、铬、锰、铁、钴等23种元素的方法。在优化的实验条件下,23种元素在一定的质量浓度范围内与其信号强度呈线性关系,标准曲线线性良好,相关系数在0.999~1.000,方法的检出限在0.0005~1.0 mg/kg,方法用加标回收测定回收率,加标回收率在80.0%~110%,对稀释沥青样品平行测定7次,测定值的相对标准偏差在0.47%~3.1%。对进口稀释沥青中23种元素进行测定,满足国家标准对各项技术指标参数的要求,检出限低,选择性好,结果准确可靠,为稀释沥青类样品中多种元素分析测定提供了新的参考方法。 展开更多
关键词 电感耦合等离子体质谱法 稀释沥青 微波消解 碰撞反应
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ICP-MS法测定镍铂合金中17个杂质元素
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作者 赵万春 李秋莹 +2 位作者 朱武勋 李玉萍 马媛 《贵金属》 CAS 北大核心 2024年第2期81-87,共7页
试样以盐酸-硝酸溶解,建立了电感耦合等离子体质谱法(ICP-MS)测定镍铂合金中17个杂质元素的方法。采用标准模式测定Mg、Al、Ti、Cr、Mn、Co、Zn、Cu、Zr、Pd、Ag、Sn、Sm、和Pb,氨气反应模式测定Si和Fe(氨气流速分别为0.2和0.25mL/min)... 试样以盐酸-硝酸溶解,建立了电感耦合等离子体质谱法(ICP-MS)测定镍铂合金中17个杂质元素的方法。采用标准模式测定Mg、Al、Ti、Cr、Mn、Co、Zn、Cu、Zr、Pd、Ag、Sn、Sm、和Pb,氨气反应模式测定Si和Fe(氨气流速分别为0.2和0.25mL/min);氦气反应模式测定V(氦气流速为5mL/min,考察了基体效应对测定结果的影响,采用内标校正提高分析的准确性,其中Mg、Al、Ti、Cr、V、Mn、Fe、Co、Zn和Si以Sc为内标,Cu、Zr、Pd、Ag和Sn以Y为内标,Sm和Pb以Re为内标。测定各元素的线性相关系数(r)不小于0.9996,方法检出限为0.0025~0.78ng/mL。对NiPt5、NiPt15、NiPt60样品中17个杂质元素进行测定,相对标准偏差(RSD)为0.86%~13.07%,加标回收率89.0%~116.5%,方法满足镍铂合金靶材的测定要求。 展开更多
关键词 分析化学 靶材 镍铂合金 杂质元素 电感耦合等离子体质谱法(ICP-MS) 反应池技术(DRC) 碰撞池技术(KED)
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电感耦合等离子体质谱法测定电镀废水中的9种金属元素
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作者 蔡海军 朱慧杰 《能源与环保》 2024年第5期59-63,共5页
为利用电感耦合等离子体质谱法(ICP-MS)实现电镀废水中微量元素的准确测定分析,通过优化碰撞反应池氦气流量实现干扰的有效扣除,为了减小测试的记忆效应以及实现待测试样的长期稳定测试,优化Au浓度占比达到良好稳定的测试效果。该方法... 为利用电感耦合等离子体质谱法(ICP-MS)实现电镀废水中微量元素的准确测定分析,通过优化碰撞反应池氦气流量实现干扰的有效扣除,为了减小测试的记忆效应以及实现待测试样的长期稳定测试,优化Au浓度占比达到良好稳定的测试效果。该方法对电镀废水直接测定,结果表明,各元素线性相关系数(R 2)均大于0.999,方法检出限为0.012~0.126μg/L,精密度均低于4.40%,试验样本加标回收率均在89.7%~107.5%。该分析方法具有操作简便、准确度好、灵敏度高等优点,对于电镀废水中的微量元素可以快速准确定量,可为电镀行业助力,也可为环境样本低含量元素的应用检测技术提供技术指导和借鉴。 展开更多
关键词 电感耦合等离子体质谱法 碰撞反应池 电镀废水 金属元素
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碰撞激活诱导的双势阱势能面可以实现9-甲基-8-氧鸟嘌呤-9-甲基腺嘌呤碱基对阳离子自由基的质子转移
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作者 May Myat Moe 刘剑波 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期330-340,I0022-I0039,I0104,共30页
8-氧鸟嘌呤(OG)是最常见的核碱基氧化损伤,它在复制过程中可以用Hoogsteen的模式与腺嘌呤(A)错误配对.0G.A碱基对不仅可以诱发G·C→T·A的颠换突变,而且由于OG的电离势和氧化电位低于天然DNA碱基更容易受到电离辐射和单电子氧... 8-氧鸟嘌呤(OG)是最常见的核碱基氧化损伤,它在复制过程中可以用Hoogsteen的模式与腺嘌呤(A)错误配对.0G.A碱基对不仅可以诱发G·C→T·A的颠换突变,而且由于OG的电离势和氧化电位低于天然DNA碱基更容易受到电离辐射和单电子氧化的影响,本文报道了[9MOG9MA]^(+)碱華对阳离子自由基的形成.和碰撞诱导解离,该碱基对利用9-甲基8-氧鸟嘌呤(9MOG)和9-甲基腺嘌呤(9MA)模拟相对应的核苷酸.实验通过电喷雾产生Cu(Ⅱ)碱基复合物继之以氧化分离产生[9MOG·9MA]^(+),并使用导向离子束串级质谱仪检测[9MOG·9MA]^(+)的碰撞诱导解离、通过测量在不同碰撞能量下的解离产物和反应截面,可以得出[9MOG-H]+[9MA+H]^(+)(主要解离通道)和9MOG·++9MA(次要通道)的0 K解离阈能分别为1.8和1.65 eV.使用密度泛函理论对[9MOG·9MA]+的结构计算发现其所有重要构象都发生了质子转移生成[9MOG-H]·[9MA+H]+.另一方面,9MOG++9MA的解离通道却需要9MOG+9MA作为中间体.看似矛盾的结果可以用碰撞活化后反应势能面上出现的双重势阱和由此触发的激发态质子转移平衡([9MOG-H]·[9MA+H]+)→←(9MOG+.9MA)*来解释.本文实验和理论研究揭示了这种生物学上重要的非规范碱基对如何在氧化和电离损伤时发生解离. 展开更多
关键词 碱基对阳离子自由基 碰撞诱导解离 碱基对内质子转移 反应势能面 电喷雾电离质谱 导向离子束散射
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Multinucleon transfer dynamics in nearly symmetric nuclear reactions 被引量:1
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作者 Fei Niu Peng-Hui Chen +1 位作者 Hui-Gan Cheng Zhao-Qing Feng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第6期67-74,共8页
Within the framework of the dinuclear system model,the multinucleon transfer dynamics for nearly symmetric nuclear collisions has been investigated.The reaction mechanism in the systems of 198Pt+198Pt and 204Hg+198Pt ... Within the framework of the dinuclear system model,the multinucleon transfer dynamics for nearly symmetric nuclear collisions has been investigated.The reaction mechanism in the systems of 198Pt+198Pt and 204Hg+198Pt was investigated at beam energies around the Coulomb barrier.It was found that the isotopic yields are enhanced with increased incident energy in the domain of proton-rich nuclides.However,the production on the neutron-rich side weakly depends on the energy.The angular distribution with the beam energy was also analyzed in the multinucleon transfer reactions.Projectile-like fragments were produced toward the forward emission with increasing incident energy.The target-like fragments manifested the opposite trend in the transfer reactions. 展开更多
关键词 Dinuclear system model Multinucleon transfer reactions Symmetric nuclear collisions Angular distribution
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Production of heavy neutron-rich nuclei with radioactive beams in multinucleon transfer reactions 被引量:3
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作者 Cheng Li Peiwei Wen +3 位作者 Jingjing Li Gen Zhang Bing Li Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第8期97-102,共6页
The production mechanism of heavy neutronrich nuclei is investigated by using the multinucleon transfer reactions of ^(136;148)Xe+^(208)Pb and ^(238)U+^(208)Pb in the framework of a dinuclear system model. The evapora... The production mechanism of heavy neutronrich nuclei is investigated by using the multinucleon transfer reactions of ^(136;148)Xe+^(208)Pb and ^(238)U+^(208)Pb in the framework of a dinuclear system model. The evaporation residual cross sections of target-like fragments are studied with the reaction system ^(148)Xe+^(208)Pb at near barrier energies. The results show that the final isotopic production cross sections in the neutron-deficient side are very sensitive to incident energy while it is not sensitive in the neutron-rich side. Comparing the isotopic production cross sections for the reactions of ^(208)Pb bombarded with stable and radioactive projectiles, we find that neutron-rich radioactive beams can significantly increase the production cross sections of heavy neutron-rich nuclei. 展开更多
关键词 多核子转移反应 重丰中子核 生产机制 放射性 蒸发剩余截面 同位素生产 入射能量 模型框架
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Studies on Ion-molecule Reaction of Disubstituted Benzene with Ion System of Acetyl Chloride in Gas Phase
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作者 LI Zhi-li (Shandong Non-metallic Material Research Institute, Jinan 250031, P. R. China) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第4期334-340,共7页
The ion-molecule reactions of disubstituted benzenes with the ion system of acetyl chloride under the chemical ionization condition were examined and the fragmentation reactions of the adduct ions formed by the ion-mo... The ion-molecule reactions of disubstituted benzenes with the ion system of acetyl chloride under the chemical ionization condition were examined and the fragmentation reactions of the adduct ions formed by the ion-molecule reactions were studied by using collision-induced dissociation technique. It was found that the electron-releasing groups favored the adduct reactions and the electron-withdrawing groups did not. The position and properties of substituting groups had an effect on the relative abundance of the adduct ions. The fragmentation reaction of the adduct ions formed by ortho-benzene diamine with the acetyl ion was similar to the reductive alkylation reaction of amine in condensed phase. 展开更多
关键词 Disubstituted benzene Ion-molecule reaction collision-induced dissociation technique ADDUCTION
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Shape Evolution of the Compound Nucleus in the Superheavy Element Synthesis Reaction via the BUU Model
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作者 韦靓 刘玉鑫 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第9期2222-2225,共4页
由带 BUU 模特儿,我们模仿超重元素合成反应。与在 BUU 模型被包括的旋转效果, non-centralityof 的效果反应 Ca-48 + U-238 -】(286 ) 112 被学习。在合成进程的有希望的影响参数能被免除零到比涉及反应的更小的原子核的半径很少小... 由带 BUU 模特儿,我们模仿超重元素合成反应。与在 BUU 模型被包括的旋转效果, non-centralityof 的效果反应 Ca-48 + U-238 -】(286 ) 112 被学习。在合成进程的有希望的影响参数能被免除零到比涉及反应的更小的原子核的半径很少小的值,这被显示出。同时,复合原子核可以包含富有的形状阶段。 展开更多
关键词 复合核子 超重元素 合成反应 BUU模型
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柔性间隙影响下涡旋压缩机主轴系统动力学特性研究 被引量:1
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作者 邱海飞 《润滑与密封》 CAS CSCD 北大核心 2023年第3期75-82,共8页
考虑到涡旋压缩机主轴系统的高速回转特性,将自由运动和接触变形两状态非连续接触模型应用于间隙运动副动力学建模。以某卧式涡旋压缩机为依据,在不同运动副间隙下构建基于ADAMS/View的主轴系统刚柔耦合模型。通过柔性接触条件下的动力... 考虑到涡旋压缩机主轴系统的高速回转特性,将自由运动和接触变形两状态非连续接触模型应用于间隙运动副动力学建模。以某卧式涡旋压缩机为依据,在不同运动副间隙下构建基于ADAMS/View的主轴系统刚柔耦合模型。通过柔性接触条件下的动力学仿真计算,深入分析了主轴系统核心部件(如动涡盘、曲轴、十字滑环及轴承)的运行状态及承载情况。结果显示:在理想间隙(间隙为0)下,柔性曲轴质心轨迹为一带有波动的非标准圆,而在非理想状态下,曲柄销与滚针轴承存在多处接触碰撞;当轴承内部存在间隙时,Z方向上的支反力更为连续和集中,且其波动幅度随着间隙增大而减小;间隙为0.01 mm时对于动涡盘加速度影响较大,不利于容积腔形成和气体压缩,而选择0.03 mm或0.05 mm间隙值时,可避免轴承系统发生应力集中和疲劳破坏,同时有助于轴承系统维护和十字滑环防自转。 展开更多
关键词 运动副间隙 柔性体 加速度 涡旋压缩机 Impact函数 接触碰撞 支反力
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电感耦合等离子体质谱(ICP-MS)法测定锰矿冶炼烟尘中多种重金属元素 被引量:1
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作者 唐碧玉 张征莲 +1 位作者 谷娟平 古行乾 《中国无机分析化学》 CAS 北大核心 2023年第7期677-683,共7页
为了准确测定锰矿冶炼烟尘中重金属元素的含量,为锰矿冶炼过程中监测和评价环境影响提供有力的数据支撑,采用HCl+HNO_(3)+HClO_(4)+HF消解体系对试样进行前处理,通过选用合适的内标溶液消除测定中的非质谱干扰,采用碰撞池模式和编辑校... 为了准确测定锰矿冶炼烟尘中重金属元素的含量,为锰矿冶炼过程中监测和评价环境影响提供有力的数据支撑,采用HCl+HNO_(3)+HClO_(4)+HF消解体系对试样进行前处理,通过选用合适的内标溶液消除测定中的非质谱干扰,采用碰撞池模式和编辑校正方程消除质谱干扰,从而建立了电感耦合等离子体质谱法测定锰矿冶炼烟尘中的Cr、Ni、Cd、Tl、Pb等多种重金属元素的方法。实验结果表明,各元素标准曲线的线性相关系数均大于0.9999,方法检出限为0.007~0.094 mg/kg,样品测定的相对标准偏差(RSD,n=11)在0.43%~4.9%,样品加标回收率为93.8%~107%。方法具有操作简便、线性范围宽、检出限低、精密度高等优点,满足锰矿冶炼烟尘中Cr、Ni、Cd、Tl、Pb等多种重金属元素同时测定的要求。 展开更多
关键词 锰矿 冶炼烟尘 重金属 电感耦合等离子体质谱法 碰撞反应池
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