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991.
Lü-Jun Yuan 《中国天文和天体物理学报》2007,7(2):281-288
A new solar telescope system is described, which has been operating at Huairou Solar Observing Station (HSOS), National Astronomical Observatories, Chinese Academy of Sciences (CAS), since the end of 2005. This instrument, the Solar Magnetism and Activity Telescope (SMAT), comprises two telescopes which respectively make measurements of full solar disk vector magnetic field and Hα observation. The core of the full solar disk video vector magnetograph is a birefringent filter with 0.1 bandpass, installed in the tele-centric optical system of the telescope. We present some preliminary observational results of the full solar disk vector magnetograms and Hα filtergrams obtained with this telescope system. 相似文献
992.
The carbohydrate and lipid contents in two planktonic crustaceans, i. e.Pseudeuphausia sinica andAcetes chinensis sampled from Xiamen coastal waters were estimated. InP. sinica, the contents of carbohydrates (in dry weight) and lipids varied from 2.19–2.33% and 21.2–21.9% respectively; inA. chinensis from 1.74–2.55% and 14.43–15.10% respectively. The analyses of fatty acids by gas-chromatograph (Model 103) showed that eight
fatty acids of 14∶0, 15∶0, 16∶0, 17∶0, 18∶0, 18∶2, 20∶2 and 22∶2 were found in these two animals, that 16∶0, 18∶0, 18∶2, and
20∶2 formed the major constituents with 91.08% (P. sinica) and 74.80% (A. chinensis) of the total fatty acids, and that the values of odd carbon types (15∶0 and 17∶0) were fairly low, 4.47% and 3.36% respectively.
Three monosaccharides: glucose, fructose, and galactose detected by high-liquid chromatograph (Waters 208) accounted for more
than 60% of the total carbohydrates, especially the glucose, exceeding by 40%. 相似文献
993.
常规共中心点抽道集叠加方法是以水平观测面,水平反射界面、均匀介质为条件,当前提条件不能完全具备时,会带来两个方面的误差,其一是CMP道集整体离散误差,其二是CMP道集内部各道之间的离散误差.通过建立相应数学模型并进行运算分析,界定了误差(离散量)的大小范围及分布规律:离散量与观测面反射界面之间的夹角、观测面高程、反射界面倾角及同道集炮检距等相关,其变化值越大,离散距离越大;相反离散距离会随观测面与反射点空间距离的增大而变小;另外介质波速越小,其垂直离散距离越大;中心点自激自收其离散量为0.对于CMP道集中诸道△t0.离散量常存在大于目的层反射波T/4的现象;炮距越大、观测界面倾角越大、介质波速越小,其△t0离散值越大,其中△t0离散值与炮检距呈非线性关系;相反反射界面埋深越大,其△t0离散越小.根据离散量对资料影响程度的分析,指出了目前共中心点抽道集叠加方法存在着局限性. 相似文献
994.
米104井位于陕西省榆林市米脂县,与米103井相距350m,设计对接靶点垂深2536.05m,造斜点垂深2330m.水平段124.79m。该井设计为三开井身结构,在施工中,根据不同的岩性采用了不同的的施工工艺及不同的钻井液。米104井钻进深度至2789m时,泥浆全部漏失,达到了一次对接成功。 相似文献
995.
套管开窗侧钻技术是处理井内复杂情况的一种有效手段,某地热井在完井抽水后,因取水段岩层垮塌造成取水井段堵塞,采用冲、扫、捞、等方法处理均无效,地热井几近报废,后采用该技术手段,使该井顺利竣工。 相似文献
996.
Su Wenbo Li Zhiming Ettensohn F. R. Johnson M. E. Huff W. D. Wang Wei Ma Chao Li Lu Zhang Lei Zhao Huijing 《Frontiers of Earth Science》2007,1(4):470-481
It is known that high-quality, black-shale source rocks occur in the uppermost Ordovician Wufeng Formation and in the lowermost
Silurian Longmaxi Formation in South China. Hence, it is important to understand their lithostratigraphy and the controls
on their deposition. A review of lithostratigraphic criteria for subdividing the two adjacent formations provides new regional
correlations between the formations and related stratigraphic successions and facies. Both the black shales and the related,
overlying flysch deposits at the Ordovician-Silurian transition in South China appear to have migrated northwestward in time
and space, reflecting probable flexural control in a foreland basin that developed in response to subduction-type orogeny
southeast of the Yangtze block. The black shales also contain K-bentonites from explosive, felsic-intermediate volcanism,
the distribution of which also supports orogeny to the southeast. Finally, the analysis of sequence stratigraphy, which shows
that the initiation of transgressive system tracts (TST) and condensed section (CS) in the related third-order sequences coincided
with the two black-shale horizons respectively, indicates that the main controlling factors for the deposition of the Ordovician-Silurian
black shales in South China are (1) northwestwardly migrating, foreland-basin subsidence caused by deformational loading related
to episodic accretion of the Cathaysia block to the Yangtze block during this period, and (2) the anoxic, sediment-starved
water column caused by rapid rise of the sea-level during the two successive phases of third-order global sea-level rise near
the Ordovician-Silurian transition in South China. In future exploration for hydrocarbon source rocks in the area, it is important
to consider likely flexural and eustatic causes for subsiding, deep, anoxic seas in recognizing other source rock intervals,
and our understanding of the Wufeng and Longmaxi formations may serve as models for future source rock exploration.
__________
Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 818–827 [译自: 地球科学—中国地质大学学报] 相似文献
997.
HE Mingqi SONG Huanbin SU Xunqing 《中国地球化学学报》2007,26(3):276-283
The Xiaolongtan copper mining district is an important area in Dali, West Yunnan, where porphyry copper deposits occur, and copper orebodies are controlled by fault or contact zone structures between porphyry massifs and country rocks. Based on detailed field investigation and deep-going analysis, the authors systematically studied the tectonogeochemical features of this mining district, proposed the principle and foundation of metallogenic prognosis, and delineated the most potential mineralization target area. 相似文献
998.
Curvilinear synthetic aperture radar (SAR), as a more practicable 3-D SAR imaging system, utilizes parametric target feature estimates extracted from the received data to reconstruct the target image. The reconstructed image quality is then impacted by the estimation accuracy of the features. In this letter, through discussing the correlation between the system parameters and the estimation performance of the curvilinear SAR, a conclusion can be drawn on how the overall location accuracy of a target is determined by the correlation between the azimuth and elevation coordinates of the flight path, compactly characterizing the curvilinear aperture. Consequently, a new index, determined only with the aperture parameters, is proposed as an aperture evaluator, which is referred to as the feature-independent aperture evaluator (FAE). FAE can be used for guiding the operational aperture design 相似文献
999.
本项目研究的是将Z/I Imaging的数字航摄相机(DMC)运用于土地详查项目,运用基于国际上先进Z/I Imaging DMC的拍摄技术获取的影像,结合影像融合技术,影像分类技术,土地信息提取技术,进行土地利用的动态监测及更新调查。 相似文献
1000.