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991.
992.
Guodong Zheng Yuhua Lang M. Miyahara T. Nozaki T. Haruaki 《Environmental Geology》2007,51(8):1455-1464
Orange precipitate was collected at the mouth of groundwater drainage tubes from the Kumanashi Landslide slip zone in Toyama prefecture, Northwest Japan. Data from XRF, X-ray diffraction, and Mössbauer spectroscopy determined the precipitate as hydrous ferric oxide (HFO) bearing multi-elements such as phosphorous, silica, calcium, etc. The occurrence of HFO may indicate an oxidation of ferrous iron in the percolated groundwater from the slip zone. Moreover, the precipitate iron should be mobilized with groundwater circulation from the slip zone, whose reducing condition was determined by the iron speciation on the same type of landslide profiles within the study area in previous studies. The HFO precipitate may be considered as a secondary reliable indicator to locate the seepage of a slip zone on surface, especially for a landslide newly investigated under wet-warm climate. 相似文献
993.
994.
平面P波在饱和半空间中洞室周围的散射(I):解析解 总被引:1,自引:0,他引:1
利用波函数展开法给出了入射平面P波在饱和半空间中圆形洞室周围散射问题的一个解析解。半空间假定为无粘性流体饱和介质,满足Biot理论。采用一种基于实验数据的孔隙率和模量之间的线性关系来确定Biot模型中的介质参数。解答考虑了透水边界和非透水边界两种情况。对边界条件进行了数值检验,结果表明,随着级数截断项数的增大,边界残量衰减很快。解答为进一步研究入射波频率和角度、边界渗透条件、孔隙率、泊松比等参数对散射的影响奠定了基础。 相似文献
995.
利用代表濮阳市公路交通状况的南乐县、范县、濮阳县公路交通事故资料和气象资料,分析了濮阳市公路交通事故发生的一般规律及其与气象条件的关系,以及几种主要气象要素对公路交通的影响,在此基础上提出了减少公路交通事故的防御措施和对策。 相似文献
996.
997.
环境空气质量背景值是一个动态值,它与污染源、气象条件和地形等因素密切相关。通过对一个环境空气三级评价案例的分析和处理中,找出背景值修正的一种思路和简易方法。 相似文献
998.
激光扫描多三维视图的全自动无缝镶嵌 总被引:1,自引:0,他引:1
探讨了不同坐标系下的三维点云统一到某一固定坐标系下形成完整目标的问题,提出了一种全自动获取三维视图配准初值的方法。对多三维视图,应用基于闭合条件的整体平差模型,获得最小二乘意义下的最优变换参数,实现了对多三笋视图的全自动无缝镶嵌。利用激光扫描仪的实际扫描数据进行了试验,得到了预期的结果,并验证了本文方法的可行性和有效性。 相似文献
999.
The effects of 60-day starvation on survival rate. condition index (CI) , changes ofnutrient composition of different tissues, respiration and excretion of scallop ChlartnCs farreri were studiedin laboratory from Oct. 17 to Dec. 15 ,1997. Two groups (control and starvation with 200 individualseach) were cultured in two 2 m3 tanks, with 31 to 32 salinity water at 1 7 “C . Starvation effects were mea-sured alter 1 0, 20, 40 and 60 days. There was no mass mortality of scallops cf the two tanks and survivalrates of the control and starvation groups were 93 .5 % and 92.0 %, respectively. Starvation had strongeffect on the meat condition of the scallops, especially after 10 days; when relative lipid percentagedropped sharply while relative protein percentage increased. The impact of starvation on the oxygen consumption mtc (OCR) and the ammonia-N cxcretion mtc (AER) was obvious. 相似文献
1000.
DING Guoan XU Xiaobin LUO Chao TANG Jie XIANG Rongbiao YAN Peng LI Xingsheng 《Acta Meteorologica Sinica》2001,15(1):21-28
The characteristics of surface O3 on clear days at Waliguan Observatory,Lin'an regional station and Longfengshan regional station in China were analyzed in this paper.The three stations belong to Global Atmospheric Watch(GAW)of WMO.There was obvious daily variation on clear days at Lin'an.with maximum(42.9 ppb)and minimum(20.3 ppb)of daily range appearing in spring and summer,respectively.The daily variation was more regular at Lonfengshan than at Lin'an.The maximum(about 27 ppb)appeared in autumn at Longfengshan.There was no obvious daily variation and also daily range was smaller in other seasons except weaker daily variation in summer at Waliguan.But the surface O3 concentration(SOC)in summer was higher than that in winter at Waliguan.The SOC on clear days of summer at Waliguan was over 20 ppb higher than at Longfengshan and Lin'an.The global radiation and NOx concentration were the main factors which control the SOC on clear days at Longfengshan and Lin'an.and played important role in different seasons and areas.The transportation of air flow around the area of Qinghai-Xizang(Tibet)Plateau was the main cause for high SOC and weak daily variation in summer at Waliguan.The similar effect of transportation was obtained at the Mauna Loa Observatory.The distribution characteristics of SOC increasing with height in the troposphere determined the difference of SOC between East China and West China. 相似文献