吉林省地质灾害类型及防治对策探讨

本文针对吉林省的地质灾害类型及各类地质灾害的成因，分布及其危害进行了论述。对其防治对策进行了探讨，提出了切合本省实际的五项防治措施。     

地球同步轨道附近哨声湍流对“种子电子”的加速

本文在等离子体准线性理论下研究了地球同步轨道附近哨声湍流对亚暴“种子电子”的波-电子共振相互作用. 当发生这种共振时，“种子电子”的动量分布函数经动量扩散而随时间演化，部分低能电子数减少了，而高能尾部分的相对论电子（能量大于1MeV）数增加了，说明“种子电子”得到了哨声湍流的有效加速，且哨声湍流的能量越高，其加速效率越高. 另外，哨声湍流的频率越低（或波数越小），共振电子的能量越高（或单位质量的动量越大）；频率范围越宽，共振电子的能量范围越宽，被加速的电子数也越多. 磁层哨声湍流加速“种子电子” 大约在30h内就可以造成相对论电子数显著增加，这正好和大多数磁暴期间观测到的相对论电子通量的增长时间相当.     

原位磁化X射线粉末衍射法测还原铁粉的微观磁致伸缩系数

首次报导X射线粉末衍射法测量铁粉晶胞的磁致伸缩系数。还原铁粉样品原位磁化后 ,铁立方晶胞产生磁致伸缩效应 ,晶胞参数的变化引起衍射峰位置和晶面间距的变化。实验测得铁晶胞λ1 0 0 为 3 .3 3× 10 - 4,此结果表明铁晶胞的微观磁致伸缩系数比棒状、薄膜或粉末压片的系数大约 16倍。对此现象进行了合理的理论解释 ,指出大块材料中的粉末多晶之间具有较大的空隙 ,从而使得宏观磁致伸缩系数变小     

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, China

Sakhaite was first discovered by Ostrovskaya, Pertsev and Nikitina at Siberia in the former Soviet Union. By using the X-ray diffraction technique, they proved that the crystal system of sakhaite was cubic (a = 1.464 nm), its possible space groups were Fm3m, F432, F43m, Fm3, F23, and its crystal chemical for-mula was Ca48Mg16(CO3)16(BO3)28Cl4(OH)8 4H2O[1]. Chichagov, Simonov and Belov studied the crystal structure of synthetic sakhaite and determined that its space group was F4132, …     

The effect of an interface boundary layer on the resonance properties of a buried structure

This paper presents a model for the analysis of the diffraction of plane waves at a cavity in an infinite homogeneous linear elastic medium supported by a segmented lining. An elastic boundary layer is introduced between the cavity lining and the infinite medium. The boundary layer is simulated by ‘elastic boundary conditions’ in which the stress is proportional to the relative displacement of the lining and of the surrounding medium boundary. A closed‐form analytical solution of the problem was obtained using the Fourier–Bessel series, the convergence of which was proven. It was shown that the number of series terms required to obtain a desired level of accuracy can be determined in advance. Using amplitude–frequency response analysis it was shown that the boundary layer produces additional ‘pseudo‐resonance’ frequencies that depend on the layer properties. These frequencies are almost identical to the eigenvalues obtained from the simple analysis of a segmented elastically supported lining. Copyright © 2003 John Wiley & Sons, Ltd.     

北京市春夏季大气气溶胶的单颗粒分析表征

采集了北京市2000年春夏季大气气溶胶样品5个，采用扫描电镜X射线能谱技术分析大气气溶胶单颗粒约2500个。研究结果表明，沙尘期间，矿物尘是最主要的颗粒物种类，非沙尘期间，北京市大气气溶胶中主要检出矿物尘和含硫颗粒物。夏季随着颗粒物污染的加重，含硫颗粒物的数目百分数增加。是北京市大气颗粒物污染的重要特征。重点讨论了Ca-S颗粒、K-S颗粒和Ca-K-S颗粒三类典型含硫颗粒物的化学组成和粒径分布特征。数目可观的Ca-K-S颗粒以及其他硫酸盐颗粒的生成与相对湿度和云量等气象条件相关，这些颗粒物可能是云中过程的产物。减少SO2排放，减少含硫颗粒物，对于控制北京市的大气颗粒物浓度水平具有重要意义。     

广东茂名高岭土煅烧实验研究

对茂名高岭土进行煅烧，结合X-射线衍射、扫描电子显微镜分析，得到了茂名高岭土在不同温度点煅烧的性能参数，并确定出其非晶化转变的温度是550℃。同时对煅烧过程中的煅烧温度、恒温时间等影响因素进行探讨，结果表明，在茂名高岭土的煅烧过程中，适当延长恒温时间可降低非晶化转变的温度，缩短恒温时间，则非晶化转变温度升高。     

四川新康风化淋滤型海泡石的热相变研究

以四川新康风化淋滤型海泡石为研究对象，利用X射线衍射分析和红外光谱分析技术，对海泡石的热相变过程及特征进行了研究。结果发现，四川新康风化淋滤型海泡石的相变过程与沉积型、热液型海泡石相变过程明显不同，其相变过程可以划分为两个阶段：800℃以下保持海泡石相；800℃以上海泡石相转化为斜顽辉石相。     

糜棱岩化过程中绿泥石多型与结晶度的演变--以郯庐断裂带南段为例

摘要：根据郯庐断裂带南段韧性剪切带糜棱岩中同构造矿物组合、黑云母的存在以及长石的变形行为，推测其变形．变质温度为400一450oC。bo值分析表明．这些糜棱岩是在低压环境下形成的。在流体作用下。糜棱岩中的绿泥石既可以交代其它矿物而形成，也可以直接从流体中结晶形成。交代其它矿物所形成的绿泥石为Ⅱ型绿泥石，其结晶度值介于0．21^。一0．23^。20．与温度具有较好的对应关系。直接从流体中结晶而产生的绿泥石初始时刻为工型．其结晶度值介于0．236^。-0．341^。20之间，多屑于近变带范畴。其指示温度要低于实际所经历的环境温度。由于糜棱岩化过程中工型绿泥石的不断产生以及工型绿泥石向Ⅱ型绿泥石转化的不充分。导致了在400以上仍然出现工型绿泥石与Ⅱ型绿泥石混合的现象．并且实测的结晶度是不同时刻形成的、具不同结晶度的绿泥石的混合结晶度。     

Seasonal variation of the total electron content, maximum electron density and equivalent slab thickness at a South-American station

Total electron content (TEC) and foF2 ionosonde data obtained at Tucumán (26.9°S; 65.4°W) from April 1982 to March 1983 (high solar activity period) are analyzed to show the seasonal variation of TEC, NmF2 (proportional to square of foF2) and the equivalent slab thickness EST. Bimonthly averages of the monthly median for January–February, April–May, July–August and October–November have been considered to represent summer, autumn, winter and spring seasons, respectively. The results show that the higher values of TEC and maximum electron density of F2-layer NmF2 are observed during the equinoxes (semiannual anomaly). During daytime, both in TEC and in NmF2 the seasonal or winter anomaly can be seen. At nighttime, this effect is not observed. Also, the observed NmF2 values are used to check the validity of International Reference Ionosphere (IRI) to predict the seasonal variability of this parameter. In general, it is found that averaged monthly medians (obtained with the IRI model) overestimate averaged monthly median data for some hours of the day and underestimate for the other hours.