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    题名 作者 年代 出处 被引量
1Determination of Fullerenes (C60/C70) from the Permian-Triassic Boundary in the Meishan Section of South China显示文摘Fullerenes (C 60 /C 70 ), clays and rocks near the Permian-Triassic (P/T) boundary in the Meishan section of South China are explored by means of comprehensive analytical techniques, including ultrasonic extraction with column purification, high-performance liquid chromatography (HPLC) and matrix assisted laser desorption/ionization time-of- flight mass spectrometry (MALDI TOF MS). The study confirms the existence of fullerenes toward the P/T event boundary and their absence in clays and limestones beyond the boundary. In particular, the white clay, known as the event boundary, contains fullerenes of 0.33 ppb, while the red material, as the first lamina fill of goethite and gypsum on the base of the white clay, contains fullerenes of 1.23 ppb, and the last lamina of 2.50 ppb. Significantly, distinct enrichment of fullerenes is coincident with the disappearance of fossil records of marine species (94%) just at the base of the white clay, implying that geological fullerenes would be one of temporal remnants led by the P/T catastrophic event. This work strongly supports that fullerenes would be one of significant records of the P/T catastrophic event but their origin remains to be studied further.LIYanfang LIANGHandong YINHongfu SUNJing CAIHou'an RAOZhu RANFanlin 2005Acta Geologica Sinica(English Edition)2005,79,1:10
2H_∞ control for stochastic systems with time-delay显示文摘The H∞-control problem of stochastic systems with time-delay is considered. The sufficient conditions are obtained, under which there are always state-feedback control and dynamic output-feedback control so that the resulting closed-loop system is internaly stable and L2 input-output stable in the sense of expectation. Furthermore, the explicit formulas of both kinds of controls are derived. An example is included to illustrate the correctness of theoretic results.LiuYungang FangRui ZhangYun LiYanfang 2005Journal of Systems Engineering and Electronics2005,16,2:0
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