Analysis of structural relaxation in a Li(2)O2SiO(2) glass using rate heating approach

The structural relaxation process of an inorganic glass (Li(2)O2SiO(2)) at different cooling rates has been studied by differential scanning calorimetry. A four-parameter model-Tool-Narayanaswamy-Moynihan (TNM) model was applied to simulate the normalized specific heat curve measured. Four parameters, Delta h*/R, beta, In A, and x were obtained and compared with the values obtained from the isothermal approach. (C) 1999 Kluwer Academic Publishers.

Response of the diatom flora in Jiaozhou Bay, China to environmental changes during the last century

The diatom flora in a 164 cm long sediment core obtained from Jiaozhou Bay (Yellow Sea, China) was analyzed in order to trace the response of diatoms to environmental changes over the past 100 years. The sediment core was dated by Pb-210 and Cs-137 and represented approximately 100 years (1899-2001 A.D.). The flora was mainly composed of centric diatoms (59-96%). The concentration of diatoms declined sharply above 30 cm (after similar to 1981 A.D.), while the dominant species changed from Thalassiosira anguste-lineatus, Thalassiosira eccentria, Coscinodiscus excentricus, Coscinodiscus concinnus and Diploneis gorjanovici to Cyclotella stylorum and Paralia sulcata. Species richness decreased slightly, and the cell abundance of warm-water species increased. We argue that these floral changes were probably caused by climate change in combination with eutrophication resulting from aquaculture and sewage discharge. (c) 2007 Elsevier B.V. All rights reserved.

微机控制与管理一体化网络在铝厂的应用

铝厂生产控制和管理一体化系统是一个横向分布,纵向分层的分层分布式集散网络系统。试系统采用集散型结构,实现了负载分散和地域分散,提高了系统的可靠性,而且维护、使用、更换、修理特别方便,具有很大的优越性。

贵州凉风洞综合体系的现代生态环境记录

基于稳定碳同位素方法, 通过对贵州凉风洞洞穴综合体系的逐项分析, 表明洞穴滴水较好地继承了土壤水所携带的地表气候与生态环境信息.