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啤酒泡沫综述 被引量:1
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作者 李根路 《啤酒科技》 2002年第4期8-11,17,共5页
本文通过对泡沫的形成、消失及其组成的全面剖析,系统地阐述了如何通过原料选择和工艺措施来提高、改善啤酒的泡沫.同时还对泡沫的不同检测方法进行了简介和比较.
关键词 啤酒泡沫 形成消失 工艺措施 检测
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Quantitative biostratigraphy and species evolutionary sequence
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作者 徐桂荣 龚淑云 +1 位作者 王永标 袁伟 《Science China Earth Sciences》 SCIE EI CAS 2001年第7期587-599,共13页
Introduction of species evolutionary sequence into the quantitative biostratigraphy is a significant work, either for studying biologic evolution or for making stratigraphic correlation and reconstructing geologic his... Introduction of species evolutionary sequence into the quantitative biostratigraphy is a significant work, either for studying biologic evolution or for making stratigraphic correlation and reconstructing geologic history. The quantitative biostratigraphy is to determine biostratigraphic event sequences by using probabilistic analysis. The evolutionary sequence systematics can efficiently ascertain species evolutionary sequences. Two methods have been proposed to determine the sequence of species-disappearance events: (1) species extinction events can be closed by last occurrence events using quantitative biostratigraphic analysis; (2) the duration of a species may be approximately replaced by the duration of its parent species. To combine these two methods for determining the sequence of species disappearance is the best way up to now. A consulting standard sequence that consists of the speciation sequence of Permian waagenophylloid corals and the biostratigraphic event sequence of other important fossils in Permian is used as an example. The group spearman rank-correlation test is used to test the consulting standard sequence by comparing four types of calculations and two kinds of sequences and to find abnormal events. Based on the found abnormal events in the test, the consulting standard sequence is revised to deal with different conditions. Sequences of speciation and species-disappearance, and species duration are determined. Application of species evolutionary sequence to quantitative biostratigraphy can largely improve the quality of biostratigraphic event sequence. In stratigraphic correlation, furthermore, event sequences have higher precision than range biozones. 展开更多
关键词 evolutionary sequence systematics quantitative biostratigraphy speciation sequence species-disappearance sequence
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