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101.
ZHU Youhai ZHANG Yongqin WEN Huaijun LU Zhenquan JIA Zhiyao LI Yonghong LI Qinghai LIU Changling WANG Pingkang GUO Xingwang 《《地质学报》英文版》2010,84(1):1-10
Qilian Mountain permafrost, with area about 10×104 km2, locates in the north of Qinghai-Tibet plateau. It equips with perfect conditions and has great prospecting potential for gas hydrate. The Scientific Drilling Project of Gas Hydrate in Qilian Mountain permafrost, which locates in Juhugeng of Muri Coalfield, Tianjun County, Qinghai Province, has been implemented by China Geological Survey in 2008–2009. Four scientific drilling wells have been completed with a total footage of 2059.13 m. Samples of gas hydrate are collected separately from holes DK-1, DK-2 and DK-3. Gas hydrate is hosted under permafrost zone in the 133–396 m interval. The sample is white crystal and easily burning. Anomaly low temperature has been identified by the infrared camera. The gas hydrate-bearing cores strongly bubble in the water. Gas-bubble and water-drop are emitted from the hydrate-bearing cores and then characteristic of honeycombed structure is left. The typical spectrum curve of gas hydrate is detected using Raman spectrometry. Furthermore, the logging profile also indicates high electrical resistivity and sonic velocity. Gas hydrate in Qilian Mountain is characterized by a thinner permafrost zone, shallower buried depth, more complex gas component and coal-bed methane origin etc. 相似文献
102.
Huancheng Ge Yuewei Ni Jinghua Li Caizhong Huang Yongqin Li Fenxia Lu Fuxi Xu Yaoming Jiang 《地震学报(英文版)》1992,5(3):549-562
The data of short-period seismograms had been collected widely in the mainland area of China not including Xinjiang and Tibet.
The physical quantities of Lg wave are determined respectively in the five subregions. The group velocities of priminary arrival
and maximum amplitude of Lg wave are equal to 3.54±0.02 km/s and 3.30±0.05 km/s, respectively. The periods of Lg waves are
between 0.2s to 1.2s, averaging 0.7s. The γ-values of Lg waves in the five subregions are equal to 0.0034±0.0001 km−1 for East, 0.0031±0.0004 km−1 for Southwest, 0.0027±0.0004 km−1 for Northeast, 0.0022±0.0001 km−1 for South, and 0.0021±0.0002 km−1 for Northwest subreqion, respectively. The average γ-value for the five subregions, γ=0.0027±0.0006 km−1. The relations among the amplitude ratioH/Z, the station correctionD
z andD
h of amplitudes, and among them and station site condition are discussed.
The subregional magnitude calibration functions ofm
Lg had been established according to each regional γ-value. From these, the unified magnitude calibration function of Chinese
mainland not including Xinjiang and Tibet was given by
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相似文献
103.
104.
105.
盐渍土的盐性是决定盐渍土地区工程治理方案所必须考虑的一个重要因素。目前盐性鉴定的方法多局限于确定单一化合物晶体,但对于自然界常是两种以上化合物共存的情况,分析鉴定还不多见。本文针对试验配制的硫酸钠、氯化钠共存的水溶液在25℃和10℃等温条件下,采用正交偏光显微镜、差热分析仪和X—衍射仪,对其固相晶体进行鉴定识别并得到如下结论: 1.在硫酸钠、氯化钠固相共存的条件下,它们各自仍保留原化合物的部分物理、热学和光学特性,仍能采用差热分析、偏光显微镜、X—衍射的方法对其进行鉴别。 2.在正交偏光显微镜下,这两种化合物共存的固相晶型与单一化合物的固相晶型光学性质略有不同,但仍存有单一化合物晶型的部分光学性质,由此能定性地进行固相鉴别。 3.利用差热分析仪和X 衍射试验表明,这两种化合物共存的固相吸热峰值、衍射峰值与单一化合物固相吸热峰值和衍射峰值有所变化,但仍有其一定的变化规律并能以此定性和半定量的鉴别哪种化合物存在与否及两者的近似比例。 相似文献
106.
The influence of the four different methods of measuring Lg amplitude, and the selection of different geometrical attenuation
coefficient ζ-values (=5/6 or 1) on the determination ofγ value of Lg wave are discussed.γ=0.0034±0.0001km−1 (when ζ=5/6) for six eastern provinces is redetermined. The revised magnitude calibration function ofm
Lg (mxh),q
E (Δ)=(5/6)logΔ+0.00147Δ+1.81 is deduced.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 171–178, 1991.
Projects sponsored by the Chinese Joint Seismological Science Foundation. 相似文献
107.
The influence of the four different methods of measuring Lg amplitude, and the selection of different geometrical attenuation coefficient ζ-values (=5/6 or 1) on the determination ofγ value of Lg wave are discussed.γ=0.0034±0.0001km?1 (when ζ=5/6) for six eastern provinces is redetermined. The revised magnitude calibration function ofm Lg (mxh),q E (Δ)=(5/6)logΔ+0.00147Δ+1.81 is deduced. 相似文献
108.
海蟑螂在中国沿海从南到北均有分布,为半陆生甲壳类生物,常栖息于近海岩礁的石缝中。海蟑螂野生资源量巨大,饲用与药用效果明显,且适应能力强,有很高的科研和实用价值。实验评估了奇异海蟑螂(Ligia exotica)幼体从出生到60日龄的生长表现,发现在45日龄后,个体体重增加开始明显加快。60日实验期间幼体增重率为7 746.51%,特定生长率为7.27%,高于其他甲壳类生物。幼体体长和体宽呈现相近的增长趋势,且体长的增长快于体宽。回归分析显示海蟑螂幼体体重与体长、体宽均具有较好的正相关性,决定系数R2分别为0.90和0.87,故可以通过体长和体宽估算其体重。实验首次实现了海蟑螂幼体的全人工培育,为其成为经济虾蟹类研究的模式动物打下了基础。且实验证实海蟑螂幼体生长速度非常快,有利于人们对其种群的开发利用。 相似文献
109.
PDC钻头广泛应用于深部硬岩钻井中,在其钻进过程中经常出现粘滑振动现象,导致钻进效率低、钻头寿命较短,针对这一难题,研制了一种新型涡轮扭力冲击器,不仅能够通过扭转冲击技术来减轻PDC钻头的粘滑振动现象,还能够适应深孔的高温钻井环境。为了充分利用泥浆的能量,考虑使用涡轮组作为动力源,然后通过万向节和减速器进行扭矩传递,最终通过冲击组件旋转实现扭转冲击。根据这一设计思路,进行了扭力冲击器的结构设计、样机试制、测试平台搭建及性能测试等工作。测试表明,新型涡轮扭力冲击器的设计方案是可行的,其冲击频率为4～5 Hz,经过计算可得单次冲击扭力为651.45～814.28 N·m,实现了初期的设计目标。 相似文献
110.
Yongqin David Chen Qiang Zhang Mingzhong Xiao Vijay P. Singh Sheng Zhang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2016,30(7):2031-2040
Forecasting of droughts is essential for developing measures for mitigation of drought hazards and for reducing drought-induced loss. In this study, droughts were characterized by the standardized precipitation-evapotranspiration index with a time scale of 3 months. Copula-based probabilistic forecasting models were developed to predict drought occurrences. Results indicated higher probability of occurrence of seasonal droughts after the occurrence of more severe seasonal droughts, and extreme drought in winter tended to persist with higher probability till spring, whereas extreme drought in autumn might not probably last to winter. Furthermore, results indicated high probability of occurrence of droughts in southeast parts of the Pearl River basin during spring to winter. Thus, droughts in the Pearl River basin are subject to lengthening duration, particularly in the southeastern part of the basin. It should be noted here that the southeastern part is densely populated with a high degree of socioeconomic development. Thus, higher probability of droughts in the southeastern part should attract considerable concern. Higher drought risk was also identified in the western part of the basin. Results of this study provide a theoretical framework for water resources management and conservation of eco-environment in the Pearl River basin in a changing climate, and may serve as a reference for evaluation of drought risk in other regions of the world. 相似文献
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