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The Phototropism of Jurassic Petrified Wood in North China Plate 被引量:2
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作者 JIANG Zikun LIU Benper +6 位作者 HUANG Min DENG Shenghui LU Yuanzheng LIU Lu LI Mingming DONG Shuxin WANG Yongdong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第5期1352-1355,共4页
Trees on the side directly exposed to sunlight generally grow faster than on the opposite side, a phenomenon termed plant phototropism. There are in situ vertical trunks of silicified wood in the Xiadelongwan area of ... Trees on the side directly exposed to sunlight generally grow faster than on the opposite side, a phenomenon termed plant phototropism. There are in situ vertical trunks of silicified wood in the Xiadelongwan area of Yanqing County, north Beijing, where the first National Geologic Park of Petrified Wood of China has been built since 2002. A few trunks have well-preserved growth rings. One petrified stump from the formation shows a positive phototropism direction of SW230°. As compared with the modern normal growth stumps in Beijing plain area, which have a positive phototropism direction of SW210 °± 5°, the evidence of wood phototropism supports the conclusion of previous palaeomagnetic studies that the North China Plate has rotated clockwise since the Late Jurassic. The known petrified wood stumps in the Yanshan-Liaoning area are mainly found from the strata of 165-136 Ma, which corresponds to the main stage of the Yanshanian Movement. 展开更多
关键词 Jurassic petrified wood PHOTOTROPISM North China plate rotation PALAEOGEOGRAPHY
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Phototropism of Petrified Wood and Its Relation with the Rotation of Different Blocks in China and the Possibility of Application in the World
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作者 Zikun Jiang Benpei Liu +6 位作者 Yongdong Wang Min Huang Tom Kapitany Ning Tian Yong Cao Yuanzheng Lu Shenghui Deng 《Open Journal of Geology》 2019年第10期585-588,共4页
Normally, trees on the side directly exposed to sunlight will grow faster than the opposing side. This phenomenon is termed plant phototropism. Moreover, palaeomagnetists have revealed that the Junnar Block has never ... Normally, trees on the side directly exposed to sunlight will grow faster than the opposing side. This phenomenon is termed plant phototropism. Moreover, palaeomagnetists have revealed that the Junnar Block has never rotated since the Mesozoic. The petrified woods in the Jiangjunmiao area of Qitai County show the positive phototropism direction of SSW220. By compared with the modern normal growth stumps in plain area, which have positive phototropism direction of SSW 219 ± 5, this observation supports the conclusion of palaeomagnetic researchers: the Junggar basin has never rotated since the Late Jurassic. 展开更多
关键词 JURASSIC petrified WOOD PHOTOTROPISM Plate ROTATION PALAEOGEOGRAPHY
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基于STG与Petrify的异步电路设计
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作者 谢晔 《现代电子技术》 2008年第16期11-14,共4页
随着集成电路设计工艺的进步,异步电路相对于同步电路的优越性将越来越明显,异步技术也将越来越成为研究的热点,预计未来集成电路设计将会更多地采用异步技术。Petri网具有的一些特性非常适用于异步电路设计。通过采用petri网的一类子系... 随着集成电路设计工艺的进步,异步电路相对于同步电路的优越性将越来越明显,异步技术也将越来越成为研究的热点,预计未来集成电路设计将会更多地采用异步技术。Petri网具有的一些特性非常适用于异步电路设计。通过采用petri网的一类子系统STG设计异步电路,并使用一个异步电路设计工具Petrify完成整个设计过程。 展开更多
关键词 集成电路 异步电路 PETRI网 状态转移图和Petrify
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A new structurally preserved fern rhizome of Osmundaceae(Filicales) Ashicaulis wangii sp.nov.from the Jurassic of western Liaoning and its significances for palaeobiogeography and evolution 被引量:8
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作者 TIAN Ning WANG YongDong +1 位作者 ZHANG Wu JIANG ZiKun 《Science China Earth Sciences》 SCIE EI CAS 2014年第4期671-681,共11页
Permineralized osmundaceous rhizome with anatomical and phylogenetic information plays a significant role in understanding the origin,evolution,and diversity variation of the fern family Osmundaceae in geological hist... Permineralized osmundaceous rhizome with anatomical and phylogenetic information plays a significant role in understanding the origin,evolution,and diversity variation of the fern family Osmundaceae in geological history.The northern Hebei and western Liaoning region is one of the most important fossil localities for the Jurassic osmundaceous rhizome fossils in the Northern Hemisphere;however,the diversity character of osmundaceous rhizome fossil remains poorly known.A new structurally preserved fern rhizome species,Ashicaulis wangii sp.nov.,is described from the Middle Jurassic Tiaojishan Formation in Beipiao City,Liaoning Province,northeastern China.The rhizome is composed of heterogeneous pith,an ectophloic–dictyoxylic siphonostele,a two–layered cortex,and a mantle of adventitious roots and petiole bases.The xylem cylinder,with complete leaf gaps,consists of 15–17 xylem strands.The petiole base is characterized by a heterogeneous sclerotic ring and numerous sclerenchyma masses in the petiolar cortex.Among five known Ashicaulis species with heterogeneous sclerotic ring,four of them are documented from China.Therefore,osmundaceous rhizome fossils from China show endemic anatomical characteristics and significances for palaeobiogeography.Comparisons of anatomical features suggest that A.wangii sp.nov.bears close similarities to Osmunda pluma Miller from the Paleocene of Dakota,USA.Fossil species of A.wangii provides new evidence for further understanding the species diversity of osmundaceous rhizome fossil in China and in the Northern Hemisphere,and contributes to exploring the macroevolution process of the Mesozoic osmundaceous plants. 展开更多
关键词 OSMUNDACEAE petrified rhizome Ashicaulis anatomical structure Middle Jurassic western Liaoning
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