Interaction of 12.7 GeV He ions with U, Pb, Au and Ag targets

The processes of production of fragments Z 8 in the interactions of 12.7 GeV ⁴He with U, Pb, Au and Ag have been analyzed using the polycarbonate track detector Makrofol. A sandwich technique was used which enables direct evidence for multiple fragment emission by a single nucleus. The decay channels ending with one, two or more (three, four) fragments were detected. A classification scheme based on the multiplicity of heavy fragments M_H (Z> 20) was used in order to identify events belonging to the different reaction channels. Cross sections, excitation energies and multiplicities of intermediate mass fragments (8 Z 20) have been evaluated for various reaction mechanisms. The experimental features of the fragmentation process have been analyzed as a function of the target mass.     

The binary decay of U,Th, Pb and Au induced by 380 MeVK − mesons

The binary decay of U, Th, Pb and Au induced by 380 MeVK ^? mesons has been studied by means of a polycarbonate plastic track detector makrofol. The range distributions of the produced fragments are discussed and some conclusions are derived on the ratio of the processes of fission and fragmentation. Also calculated mass and energy distributions of the fragments produced by the uranium fission are presented.     

ICP-AES法测定松香中铁、铅、铜、锌、铝

本文研究了用ICP－AES法测定松香中的铁、铅、铜、锌、铝的方法，确定了松香中杂质元素同时测定的最佳工作条件，并对实际样品进行了AAS法对比测定，回收率在91％－104％之间，结果令人满意。该方法快速、简便、可靠，适用于出口松香的日常检验。     

ICP-AES法直接测定锡锭中的As、Al、Bi、Cd、Cu、Fe、Pb、Se、Sb、Zn

以电荷耦合器件为检测器的全谱直读等离子体光谱仪直接测定锡锭中As、Al、Bi、Cd、Cu、Fe、Pb、Se、Sb、Zn十种杂质元素的含量.该方法简便、快速且具有比化学法更低的检出限,加标回收试验结果表明,回收率为92%-105%,RSD均小于1.5%.     

Stopping powers of C,N and O ions in Cr,Fe, Co,Ni, Cu and Zn in the 1 MeV region

The stopping powers of C, N, and O ions in Cr, Fe, Co, Ni, Cu and Zn in the energy range 500 keV to 2 MeV have been measured relative to that for He ions in the same material. The measurements were made utilizing energy spectra of particles backscattered from thick substrates of the target material into which a heavy material (Bi) had been previously implanted to a shallow depth. Assuming that dE/dx for He is known, the dose of implanted Bi can be determined from a He backscattering spectrum. Then this dose is used to calculate the unknown stopping power from a backscattering spectrum of the ion to be studied.

The data are analysed in terms of a function dE/dx=aE ^p +b The experimental results give values of p ranging from 0.3 to 0.5. Our absolute dE/dx values (normalized to known dE/dx values for He ions) are somewhat higher than those tabulated by Northcliffe and Schilling⁽³⁾ and considerably higher than predicted by the LSS⁽⁶⁾ theory.     

ICP-AES测定铜电解液中的Fe、Ni、Pb、Bi、Sb、Zn和As

利用ICP-AES分析技术,通过对样品处理、元素分析谱线、酸度等因素进行试验研究,综合确定了分析条件,对铜电解液中杂质元素（Fe、Ni、Pb、Bi、Sb、Zn、As）进行了ICP-AES测定。结果表明,ICP-AES测定铜电解液中Fe、Ni、Pb、Bi、Sb、Zn和As,可以满足铜电解生产的需要,为高纯阴极铜的生产起了指导作用。     

ICP—AES法直接测定锡锭中的As,A1,Bi,Cd,Cu,Fe,Pb,Se,Sb,Zn

以电荷耦合器件为检测器的全谱直读等离子体光谱仪直接测定锡锭中Ａｓ、Ａ１、Ｂｉ、Ｃｄ、Ｃｕ、Ｆｅｄ、Ｐｂ、Ｓｅ、Ｓｂ、Ｚｎ十种杂质元素的含量。该方法简便、快速且具有比化学法更低的检出限,加标回收试验结果不明,回收率为９２％－１０５％,ＲＳＤ均小于１．５％。     

原子吸收法同时测定大豆及其乳制品中Zn、Cu、Co、Fe、Mn

本文采用干法灰化和湿法消化溶解样品，原子吸收法测定大豆及其乳制品中Zn、Cu、Co、Fe、Mn等元素。方法快速、简便，回收率为96％－103％。     

ICP-AES法测定蚂蚁酒中的Fe、Cu、Zn、Ca、Al、Pb、P

本文采用ICP－AES法测定蚂蚁酒中的Fe、Cu、Zz、Ca、Al、Pb、P等几种微量元素,根据各元素的谱线背景及干扰,选择了最佳分析谱线。方法的相对标准偏差为2．08％－2．84％,准确度及回收率均令人满意。     

稚鸡蛋中Ca、Cu、Fe、Zn、Mn、Se、Cr和Pb含量的测定

采用原子吸收光谱法,测定了稚鸡蛋中的钙、铜、铁、锌、锰、硒、铬和铅的含量,并对其结果进行了分析。各元素在实验范围内,线性关系良好,回收率在97.9%—102.2%之间。稚鸡蛋中Ca、Cu、Fe、Zn、Mn、Se含量分别为973.2、5.86、419.40、99.78、7.66、1.25μg·g~(-1),显著高于罗曼鸡蛋。测定结果显示稚鸡蛋中含有丰富的矿物元素,具有较高的营养和保健价值。     

ICP-AES同时测定满山香子中的铜、铁、锌、钙、镁、锰和钴

电感耦合等离子体发射光谱法 (ICP- AES)测定中药满山香子中的铜、铁、锌、钙、镁、锰、钴等 7种元素的含量。研究了样品溶解酸、元素分析线的选择。各元素测定的相对标准偏差为 1.6 0 %— 6 .38% ,加标回收率为 97.0 0 %— 10 5 .0 0 % ,方法方便、可靠 ,具有良好的准确度和精密度。     

Reaction and fission cross-sections of 750 A·MeV238U ions on Pb,Cu and Al-targets

Charge-loss and fission cross-sections of²³⁸U at 750 A·MeV were measured on Al, Cu and Pb targets. The charge-loss rate was obtained by the attenuation method. Fission was selected by detecting the pair of highly ionizing fragments. Since the neutron-loss cross sections were measured in a parallel experiment for the same projectiles, all cross sections contributing to²³⁸U collisions on nuclei are available now as function of the target mass number and can be compared with current models.     

Analysis of shower particle pseudorapidity spectra in interactions of relativistic Au and Pb ions with emulsion nuclei

The pseudorapidity spectra of fast particles (with β > 0.7 ) produced in Au (at 11.6 A GeV) and Pb (at 158 A GeV) induced collisions with emulsion (Em) nuclei contain some visual plateaus and shoulders. The plateau is wider for Pb+Em reactions compared with the Au+Em ones. The existence of a plateau is expected for parton models. The Fourier transformation and maximum entropy methods were used to get additional information about the plateaus. The dependence of the plateaus on the centrality of the collisions was also studied using the number of g-particles to fix centrality. It shows that the maximum entropy method could confirm the existence of the plateau and the shoulder on distributions.     

直读光谱法测定无铅焊料中的铅、镉、铜、银、铋、砷、锑和铁

提出了直读光谱法同时测定无铅焊料中铅、镉、铜、银、铋、砷、锑和铁的方法,该方法准确度高、精密度好、测定速度快,已在生产控制过程中得到应用.     

Cross sections for interactions of 8.8 GeVα particles with Ag,Au, Bi and Th

Makrofol was used as 4π track detector to determine reaction cross sections of Ag, Au, Bi and Th induced by 8.8 GeVα particles. The variation of cross sections as functions of theZ ²/A parameter of the target has been investigated. Data concerning geometry of events, momentum transfer and fission probabilities were discussed in order to discern fission products from those originating from more violent processes. Comparison with proton data has been done and differences were discussed.     

Measurement of total M shell photoionization cross sections for Au,Pb, Th and U in the energy region 6–12 keV

The total M shell relative photoionization cross-sections for Au, Pb, Th and U have been measured in the energy region 6–12 keV. External conversion K X-rays of suitable elements has been employed as incident photons to photo ionize the total M shell of elements under investigation. The method provides relative cross-sections therefore does not make use of theoretically calculated average M shell fluorescence yields which involve uncertainties of the order of 20%. No evidence of deviation from calculated values of cross-sections have been observed within experimental errors for all incident photon energies.     

ICP-MS测定纯铜中的铋、镍、铅和锌

ICP-MS测定纯铜中的铋、镍、铅和锌,简便、快速,其检出限为0.03—0.90μg/g之间,准确度及精密度均能满足分析要求。     

Large magnetothermoelectric power in Co/Cu, Fe/Cu and Fe/Cr multilayers

We report and discuss experimental data on the thermoelectric power of magnetic multilayers. Measurements of the thermoelectric power of Fe/Cr, Co/Cu and Fe/Cu multilayers have been carried out in the temperature range 4K < T < 150 K magnetic fields perpendicular to the layers. All specimens were found to exhibit pronounced magnetothermoelectric power (MTEP) effects correlating with their giant negative magnetoresistance. The main difference between the MTEP and the magnetoresistance is in their temperature dependence. Whereas the magnetoresistance is a decreasing function of temperature, the MTEP, at least in Co/Cu and Fe/Cu multilayers, is very small at low temperature and increases rapidly above 30–40 K. We ascribe this high temperature part of the MTEP to spin-dependent electron-magnon scattering and we propose a theoretical model.     

Magnetic irreversibility lines and critical currents of Bi(2212) single crystals doped by Fe, Ni, Co and Zn

We report measurements of the AC-susceptibility and the irreversible magnetization of Bi(2212) single crystals doped with up to 2 at.% of Fe, Ni, Co and Zn on the Cu position. Low concentrations of the doping elements, typically below 1 at.%, definitely increase the pinning force density and shift the magnetic irreversibility lines towards higher fields. In contrast, higher concentrations strongly suppress the critical current density and the irreversibility fields. A special situation occurs in the regime of low temperatures below about 10 K where we find that even very low concentrations of the doping elements are deteriorative for the critical current density.