700—2000eV电子对氧分子的散射全截面绝对测量

介绍中能电子与氧分子的散射全截面测量，给出７００—２０００ｅＶ电子对氧分子的绝对散射全截面，高于１６００ｅＶ能区没有同类数据的文献报道．实验结果的系统误差和统计误差各为３％．对结果与已有的实验和理论结果作了比较．     

1keV以上电子对乙烯的散射全截面绝对测量

介绍中能电子与乙烯分子的散射全截面绝对测量，给出１１００～１４００ｅＶ电子对乙烯分子的绝对散射全截面。实验结果的系统误差和统计误差均约为４％。本结果与已有的实验值和理论值作了比较，还对三组等电子数分子实验的电子散射全载面与分子的大小极化率的关系进行了探讨。     

正电子散射中的关联极化势

本文提出了一种无任意参数的正电子与原子的关联极化相互作用势，并用之对氩原子激发阀值（１１．０７ｅＶ）以下的低能正电子被Ａｒ散射的截面进行了计算，对计算结果进行的分析及与实验的比较证明了所提极化势模型的合理性。     

慢电子与氖原子的弹性散射研究

采用处理慢电子被原子散射的等效势模型,计算了能量在0.1～80 eV范围内电子与氖原子系统的弹性散射总截面、动量转移截面和微分截面,并将其结果与已有的较为准确的理论和实验值进行了对比.还讨论了Hammetling交换势中比例系数取不同数值时对结果的影响.     

慢电子被氩原子的弹性散射

本文考虑到外来电子对靶原子的极化效应,外来电子与靶原子的电子之间的交换相互作用以及在靶原子场中外来电子运动状态的畸变,利用原子解析波函数,推导出外来电子与氩原子之间相互作用势的解析表达式。通过引入“对势函数的有效核电荷”,讨论了氩原子场的物理特征。用量子力学的分波法计算了慢电子在氩原子场中运动的畸变波函数以及慢电子被氩原子弹性散射的相移、微分截面、分波截面、总截面和动量转移截面。数值计算结果与实验数据符合得很好。估算了被弹性散射的电子自旋出现完全极化的临界能量和临界角度。研究了极化效应和交换效应对慢电子散射过程的影响。     

电子与原子碰撞中关联极化势研究

本文根据文献~([3])中提出的不含自由参数的新的关联极化势公式,对低能电子被氖和氩原子弹性散射的截面进行了计算,获得了相当满意的结果。     

电子被氨分子散射总截面的计算

本文利用光学势方法计算了能量在１０－１０００ｅＶ范围内电子被氢原子和氮原子散射的总截面，并利用可加性规则得到了电子被氨分子散射的总截面．计算结果与实验进行了比较，在２００—１０００ｅＶ能量范围内计算结果和实验结果符合得比较好．     

电子被原子非弹性散射的光学模型势方法

本文将原子核散射理论中的光学势方法应用于电子─原子散射计算中，提出了不含任意参数的光学模型势，用自编的Ｆｏｒｔｒａｎ程序计算了ｅ─Ｈｅ的散射总截面，获得了与实验符合的结果．     

1～50eV电子－N_2散射总截面的绝对测量

报道了利用飞行时间（ＴＯＦ）谱仪对电子－Ｎ２散射总截面进行绝对测量的结果及其误差，与其它实验数据比较的结果表明，在实验误差范围内符合较好     

电子被CO分子散射总截面的分析

本文根据Ｂｏｒｎ近似提出了一种电子被双原子分子散射总截面的拟合公式，并对ＣＯ分子进行了拟合，分析了其中参数的规律，并阐明了其物理含义，进而给出了直接近似计算散射截面的方法．计算结果与实验和理论结果符合得很好，结果表明Ｃ和Ｏ原子的核间距在ｅＣＯ散射过程中起着关键性的作用     

Noble gases in corundum megacrysts from the basalts in Changle, Shandong Province, eastern China

This study presents noble gaseous data of the corundum megacrysts from the Cenozoic basalts in Changle, Shandong Province, eastern China. It is known that no noble gaseous data of corundum megacryst have been documented before. The 3He/4He ratios (1.13-7.37 Ra) of the corundums from Changle vary from atmosphere to MORB values; the 20Ne/22Ne (9.67-10.75) and 21Ne/22Ne (0.0280-0.0372) data define two linear trends on Ne three-isotope diagram, respectively, along the MFL and the correlation line between atmosphere and MORB; the 38Ar/36Ar (0.177-0.194) ratios, the 40Ar/36Ar (280.9 -404.2) ratios and the 128-136Xe/132Xe ration with obvious 129Xe excess are generally higher than at-mospheric component, but the 40Ar/36Ar ratios are much closer to atomospheric ratio. The isotopic compositions of noble gases (particularly for He and Ar) of the corundums are similar to those of py-roxene, anorthoclase megacrysts, and mantle-derived xenoliths from this area, and those of man-tle-derived xenoliths from several areas in eastern China. Therefore, the noble gases trapped in the corundums probably are from mantle source, representing a ‘mixed fluid' produced by the interaction between the lithospheric mantle and fluids releasing from the convective plate. Both the noble gas isotopic compositions and the oxygen isotopic compositions of the solid corundums are not the characteristics of crustal source. These suggest that the corundums crystallized from mantle-derived magmas with minimal crustal contamination.     

滇西富碱斑岩型多金属矿稀有气体同位素组成特征及地质意义*

通过对滇西富碱斑岩型多金属矿区稀有气体同位素组成的研究表明,黄铁矿和石英脉等流体包裹体中3He/4He值主要为0.160 8~3.470 0 Ra,远高于地壳特征值,而整体略低于地幔特征值;20Ne/22Ne和21Ne/22Ne平均值分别为11.271和0.032 2,接近地幔同位素组成;40Ar/36Ar和38Ar/36Ar平均值分别为395.51和0.197 6,均高于大气比值,而低于MORB比值;128~136Xe/130Xe值与大气相比均表现出过剩的特征。综合研究表明,滇西多金属矿区包裹体中稀有气体同位素组成在显示含矿流体的幔源特征的同时,又表现出强烈的地壳特征;成矿流体主要源于深部地幔,在参与交代蚀变过程中,其性质由熔浆向热液过渡,同时引发壳幔物质叠加混染,正是这种流体作用构成了滇西新生代富碱斑岩多金属成矿的内在统一制约因素。     

Noble gas isotopic compositions of deep carbonate rocks from the Tarim Basin

Abundances and isotopic compositions of noble gases (He, Ne, Ar, Kr) with various existence states in carbonate rocks from the Tacan1 Well have been investigated by means of the stepwise heating technique. The elemental abundance patterns of noble gases in the samples show the enrichment of heavy noble gases and depletion of ²⁰Ne relative to the atmosphere, which are designated as type-Ⅰand are similar to that observed in water, natural gases and sedimentary rocks. The ³He/⁴He ratios of deep carbonate samples at lower and medium temperature (300—700℃) and a majority of samples at higher temperature (1100—1500℃) steps are very similar to those of natural gases in the same strata in this area, this feature of radiogenic crustal helium shows that the Tazhong Uplift is relatively stable. However, significant helium and argon isotopic anomalies are found at the 1100℃ step in the Middle-Upper Ordovician carbonate rock, suggesting the incorporation of mantle-derived volatiles, this may be due to minor igneous minerals contained in sedimentary carbonate rocks. The ⁴⁰Ar/ ³⁶Ar ratios in the Cambrian carbonate rock are slightly higher than those in Ordovician carbonate rocks, which may reflect the influence of the chronologic accumulation effect of crust radiogenic ⁴⁰Ar. Argon isotopes of various existence states in source rocks are much more different, both ³⁸Ar/ ³⁶Ar and ⁴⁰Ar/ ³⁶Ar ratios at the higher temperature steps are higher than those at the lower temperature steps.     

Noble gas and cosmic-ray exposure age of Juancheng chondrite

The analytical results of noble gase in recently fallen Juancheng chondrite indicate that cosmic-ray ages of cosmogenic nuclei of³He,²¹Ne and³⁸Ar are 5.1, 5.0 and 5.8 Ma, respectively, averaging 5.3 Ma. The gas retention ages radiogenic nuclei of⁴He and⁴⁰Ar are 3 200 and 4 200 Ma, respectively. The average cosmic-ray age shows that it has occurred at breakup of the meteoroid from its parent body by impact before 5.3 Ma.     

6—30keV单电荷离子与H2分子碰撞的单电子剥离截面的测量

用增长率方法测量了６－３０ｋｅＶＨｅ＾＋，Ｎｅ＾＋，Ａｒ＾＋，Ｋｒ＾＋，Ｘｅ＾＋及Ｃｌ＾＋离子与Ｈ２分子碰撞的单电子剥截面，Ｈｅ＾＋的截面数量与他人数据一致，其他的截面数据在此之前未见报道。     

相对论重离子碰撞中粒子的鉴别

根据聚合级次定律提出一种相对论重离子碰撞中粒子鉴别的新方法。采用该法分析了Ｂｅｖａｌａｃ流光室１．２Ａ ＧｅＶＡｒ＋ＢａＩ２和２．１ＡＧｅＶ Ｎｅ＋ＮａＦ４π实验事件中ｚ≤２的粒子及碎片的产生几率。发现了粒子鉴别前后两种实验事件快度分布的变化。     

CR-39塑料蚀刻径迹探测器中重离子径迹的重建

本文利用最小二乘法原理对CR-39塑料蚀刻径迹探测器中重离子径迹的重建方法进行了讨论,并根据径迹重建技术测量了400 A MeV20Ne与C,CH2,Al靶作用射弹碎裂的总截面,所得结果与其他能区实验结果在实验误差范围内一致.     

惰性气体和H_2分子碰撞截面计算研究

用T .T(K .T .TangJ.Peter .Toennies)势模型和公认精密度较高的密耦 (Close -Coupling)近似方法计算了E =0 .0 5ev时 0 0 - 0 0弹性碰撞 0 0 - 0 2非弹性碰撞 ,得出氢分子转动激发分波截面 ,并研究了原子与分子碰撞弹性分波截面和非弹性激发截面随量子数增加的变化规律 .     

Cosmic-ray exposure and gas retention ages of the Guangmingshan (H5) chondrite

Isotopic compositions of noble gases from the Guangmingshan chondrite were analyzed. Based on the analyses of cosmogenic nuclei, cosmic-ray exposure age of the meteorite is (65±10.0) Ma (³He), (80±12) Ma (²¹Ne) and (65±10.0) Ma (³⁸Ar), with an average of 70 Ma. This is the highest exposure age of H-group ordinary chondrites. Gas retention ages of K-Ar and U, Th-⁴He are (4230±100) Ma and (3300±60) Ma, respectively. The smaller ages of³He than²¹Ne and⁴He than⁴⁰Ar suggest that both³He and⁴He lost together. This is probably related to a solar heating effect of a meteorite with a small perihelion during the last exposure period.