南极中国长城站地区西湖沉积物的地球化学行为与环境

本文对取自长城站区西湖水下沉积物260cm岩芯采用中子活化等方法分析得出:湖区周边的新生代火山岩构成了西湖沉积物的主要物源.粘土粒级中元素有明显的化学分异作用.沉积物中Cs/Rb,Br/Cl,La/Yb,CaCO_3及粘粒中阳离子代换量的变化表明3.6ka B.P.以来,气候存在温和—寒冷—温和的变化,反映该区冰盖进退的历史.     

几种饱和脂肪酸及其盐的拉曼光谱研究

饱和脂肪酸及其盐在自然界中广泛存在,它们也是重要的化工原料.但是有关此类物质拉曼光谱特征的研究尚属少见.为了进一步了解它们的拉曼光谱特征,对乙酸、硬脂酸及乙酸钙、乙酸镁、硬脂酸钙、硬脂酸镁进行了拉曼光谱研究.从指认这6种物质拉曼光谱的特征峰拉曼位移出发,对它们的相应谱峰进行比对与分析,探讨了阳离子的引入对饱和脂肪酸及其盐的拉曼光谱的影响,找出了它们拉曼光谱的差异.比较不同阳离子形成的饱和脂肪酸盐的特征峰拉曼位移的差别,从折合质量和核外电子构型角度解释了造成差异的原因.同时发现了长碳链可以减弱不同阳离子对饱和脂肪酸盐拉曼光谱造成的影响.     

TIME-VARYING FILTERING FOR ELIMINATING MULTIPLE ECHOES IN PROFILING SONAR

A new method,time-vrying filtering(TVF)for eliminating multiple echoes in the profilingsonar is suggested.It operates in real time and is easy to implement.In a conventional profilingsonar operation for acquiring sub-bottom structural imformation,data are often masked by mul-tiple reflection between the surface and the water-bottom interface,making the chart very difficultto interpret.The analysis shows that the multiple echoes can be greatly attenuated or even eliminat-ed,when the filter is designed according to the maximum S/N criterion.A system using this tech-nique has been develped and the experimental results obtained on the sea are quite satisfactory.     

GEOCHEMISTRY OF SEDIMENTS AND ENVIRONMENT IN XIHU LAKE OF GREAT WALL STATION OF CHINA, ANTARCTICA

The determined results in this paper, which were obtained by the multielement analysis of the 260 cm-deep core sediments under the water of Xihu Lake in the Great Wall Station area, are as follows: The Cenozoic volcanic rocks around Xihu Lake are the main source of sediments in the lake. The chemical differentiation in very fine particles is still detectable. From the variation of ratios of the Cs/Rb, Br/CI and La/Yb in the clay fraction with depth and from the variation or CaCO_3 contained in the sediments, cation replacing amount in the clay grains and the sediment grain sizes in time, it can be seen that since 3600 a. B. P., there has existed the climatic variation of warm-cold-warm, which embodies the advance and retreat history of the ice sheet in this area.     

剖面声呐中多次反射的时变过滤

本文提出并发展了一种新的适用于地层剖面声呐的信号处理技术——时变滤波.它简单易行,并且是实时的.分析表明:它能大大削弱甚至完全消除这种声呐技术中最令人讨厌的多次反射干扰,而同时保持输出信噪比接近理论上的最大值.海上实验得到了令人满意的结果.     

利用红外光谱鉴别饱和脂肪酸及其盐

有人认为饱和脂肪酸及其盐是碳酸盐岩中的生烃母质,但将它们从天然沉积物中鉴别出来的方法尚不成熟,对分析评价它们在沉积物中的分布造成困难.文章对几种合成饱和脂肪酸及其盐进行红外光谱测试,获得它们的红外吸收光谱.对特征峰进行指认,分析了饱和脂肪酸及其盐红外光谱的区别.从基团推电子能力、分子折合质量、离子核外电子构型及碳链长度的角度,解释不同饱和脂肪酸以及不同阳离子形成的饱和脂肪酸盐的特征官能团吸收峰波数的变化规律.为地质体中此类物质的鉴别提供参考.