甲壳单糖、寡糖、低聚糖制备方法的优化与比较研究

该文通过大量实验,确定了制备单糖、寡糖及低聚糖的最佳生产工艺,并对几种制备方法做了比较研究.该文采用氧化降解和微波降解等不同技术对甲壳低聚糖的制备工艺进行了研究.H<,2>O<,2>作为氧化剂,在酸性条件下,采用4因素3水平进行正交实验,得到了制备分子量2000以下的寡糖的最佳条件.微波降解制备低聚糖目前尚未见报道,经过该实验证明此方法可降低能耗,减小污染,节省时间和原料,是一个具有产业化前景和市场潜力的好方法.通过以不同的壳聚糖为原料,探讨了在微波场作用下纯溶剂及盐效应对分子量变化的影响,最终产物的分子量均在1×10<'5>～10×10<'5>之间.根据IR光谱,壳聚糖降解前后主要峰的位置都无变化,只是随壳聚糖相对分子质量的降低各峰峰强有所变化,证明了壳聚糖氧化降解及微波降解制备寡糖、低聚糖是以开裂壳聚糖的β-1.4糖苷键来进行.该项研究对更好的开发利用甲壳质资源,促进中国海洋生物制品的发展具有十分重要的意义.

黄海海域前新生代残留盆地综合地质地球物理研究

China’s annual oil import volume has been increasing in recent years, but the oil price in the international market fluctuates and poses a severe threat to China’s economic development and national security. Therefore, it is of great importance to study the gas and oil exploration of Pre-Cenozoic Residual Basins in Yellow Sea. Yellow Sea has widespread and thick Mesozoic and Paleozoic strata that contain multilayer source rock. Hence, Yellow Sea Mesozoic and Paleozoic strata have good conditions of forming Pre-Cenozoic hydrocarbon reservoirs. Pre-Cenozoic Residual Basins are usually buried deep and then transformed many times in its long evolutional history. These characteristics make it difficult to apply a single method in exploring Pre-Cenozoic Residual Basins. On the other hand, it is highly effective to solve key problems of gas and oil exploration of Pre-Cenozoic Residual Basins in Yellow Sea by using integrated geological and geophysical methods which make full use of the advantages of various exploring techniques. Based on the principle of “the region controls the local; the deep restricts the shallow,” this study focuses on Pre-Cenozoic Residual Basins in Yellow Sea to describe the structure frame of its distribution, with gravity, magnetic, seismic, drill-hole and geological data and previous research findings. In addition, the distribution characteristics of Pre-Cenozoic Residual Basins in Yellow Sea are also analyzed. This paper explores the characteristics of error between gravity forward with constant density and gravity forward with variable density through the study on 2-D and 3-D gravity forward in frequency domain. The result shows that there is a linear relationship between error and depth of 2-D geological model but there is a nonlinear relationship between error and depth of 3-D geological model. The error can be removed according to its linear characteristics or statistical nature of nonlinear characteristics. There is also error between gravity inversion with constant density and gravity inversion with variable density due to variable density and edge-effect. Since there are not noticeable rules between the error and the two causes as variable density and edge-effect, this study adopts gravity inversion with variable density and methods to eliminate the edge-effect in basement inversion to improve inversion accuracy. Based on the study on the rock physical properties and strata distribution of Yellow Sea and adjacent regions, this study finds that there is a big density contrast between Cretaceous-Jurassic strata and their substratum. The magnetic basement of south Yellow Sea is regarded as top of Archeozoic-Proterozoic early strata, and there are double magnetic basements in north Yellow Sea. Gravity and magnetic data are used to inverse the gravity basement and magnetic basement of Yellow Sea, with seismic and drill-hole data as constrains. According to data of gravity and magnetic basement distribution, the depth of Cenozoic strata and previous research findings, this paper calculates the thickness of the Mesozoic and Pre-Mesozoic Residual Basins, draws the distribution outline of Pre-Cenozoic Residual Basins in Yellow Sea, and analyzes its macro-distribution characteristics. Gravity inversion is applied on a typical geological profile in Yellow Sea to analyze the characteristics of its fractures and magnetic basements. The characteristics of Pre-Cenozoic Residual Basins distribution outline in Yellow Sea and the fractures and magnetic basements of its typical profile shown by profile inversion provides new geophysical evidence for these structure views such as “the South Yellow Sea and the North Yellow Sea belong to different structural units” and “Sino-Korea and Yangtze blocks combine along Yellow Sea East Fractured Zone in Yellow Sea”.