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91.
在煤田测井中,井径的变化对其它测井参数是一种干扰,但利用井径的相对变化值(井径扩大系数),可有效地评估岩石的强度等级和可采煤层顶底板的稳定性。统计鱼卡煤田东部勘探区29个钻孔孔径的变化值,按岩石抗压强度划分原则,将其七煤顶板稳定性划分为5个等级,据此固定了该煤田七煤顶板稳定性分布图。 相似文献
92.
自动气象站维护及操作技巧 总被引:1,自引:0,他引:1
对自动气象站软件、硬件及网络通信三个方面的主要故障现象进行了总结,介绍了使用维护注意事项和技巧,提出了故障排除方法。 相似文献
93.
张家界生态旅游可持续发展探讨 总被引:4,自引:2,他引:4
张家界拥有丰富的生态旅游资源,近年来旅游业发展迅速。但是旅游开发给自然保护区造成了较大的环境污染和生态破坏。为了实现张家界旅游业的可持续发展,必须由传统的大众旅游模式转向可持续发展的生态旅游模式。在分析目前张家界生态旅游发展存在问题的基础上,提出了张家界生态旅游可持续发展的对策,给出了贯彻可持续发展思想、明确功能分区、完善环保法规、控制旅游规模、增强群众环境意识以及扩展东西线、搞好城区环境建设等7方面的建议。 相似文献
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The evaluation of the wave-induced pore pressure around a buried pipeline is particularly important for pipeline engineers involved in the design of offshore pipelines. Most previous investigations of the wave-induced dynamic response around an offshore pipeline have limited to two-dimensional cases. In this paper, a three-dimensional model including buried pipeline is established, based on the existing DYNE3WAC models. Based on the proposed numerical model and poro-elastic soil material assumption, the effects of wave and soil characteristics, such as wave period, water depth, shear modulus and permeability, and configuration of pipelines, such as pipeline radius and pipeline buried depth, on the wave-induced excess pore pressure will be examined. Numerical results indicated that the normalized excess pore pressures versus z/h near the pipeline increase as the obliquity angle, wave period and water depth increase, and they decrease as the burial depth and radius of pipeline increase above the pipeline. Soil permeability has obvious influence on the wave-induced normalized excess pore pressure, and different soil material will result in distinct computation results. 相似文献
97.
Xianglan Kong Shengxin Cai Tianjiao Zhu Qianqun Gu Dehai Li Yepeng Luan 《中国海洋大学学报(英文版)》2014,13(4):691-695
In order to obtain novel secondary metabolites, a deep sea inhabiting fungus Aspergillus versicolor CXCTD-06-6a was investigated. One new diketopiperazine brevianamide W(1a), as well as five known diketopiperazine alkaloids, diketopiperazine V(1b), brevianamide Q(2), brevianamide R(3), brevianamide K(4), and brevianamide E(5), were isolated from the Et OAc extract of the fermentation broth. Their structures were elucidated by spectroscopy techniques(NMR, MS). The six compounds exhibited moderate radical scavenging activity against DPPH with clearance ratio of 55.0%(1a and 1b), 53.7%(2), 46.2%(3), 61.4%(4) and 19.3%(5) at a concentration of 13.9 μmol L-1, respectively; while the positive control ascorbic acid showed a ratio of 70.3% at the concentration of 28.4 μmol L-1. 相似文献
98.
Zhen Liang Xianjia Peng Jun Wang Zhaokun Luan Zhimei Liu Yunxia Wang 《Environmental Earth Sciences》2011,63(2):221-228
Sewage sludge contains large amount of water-soluble phosphorus, which is prone to runoff loss when sewage sludge is land
applied. Phosphorus export from sewage sludge is an important cause for water eutrophication. Immobilization of phosphorus
before sewage sludge land application seems necessary. In this study, three amendments including red mud (RM), lime and mixture
of RM and lime were employed to immobilize phosphorus in fresh sewage sludge. It was found that phosphorus was effectively
controlled by RM, lime and mixture of RM and lime. Sequential chemical extraction results indicate that the RM amendment transformed
H2O-P in the sewage sludge into the NaOH-P, while the lime amendment transformed H2O-P in the sewage sludge into the HCl-P. Such transformations in phosphorus fractions would have little influence on phosphorus
availability but would retard and reduce potential phosphorus loss following sewage sludge was land applied. 相似文献
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