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11.
地倾斜台站数字化、模拟观测数据频率特性研究 总被引:2,自引:2,他引:0
分析了四川、云南的部分地倾斜数字化观测与模拟观测资料的特性,从频率范围,周期10天以上的FFT谱特性,固体潮波振幅,相位特征值等方面,论述了地倾斜数字化资料较模拟记录资料的信息组成变化,并对资料的分析与应用进行了初步探讨。 相似文献
12.
1StrongtideandastronomicalconditionsPartial solar eclipse occurred 4 times in 1964, 1982 and 2000 respectively. Time interval is about 3 Saros periods (one Saros period is 18 years and 10.33~11.33 days). Total lunar eclipse occurred 2 times in 1964 and 2000 respectively and 3 times in 1982. However, there was no lunar eclipse in 1966, 1984 and 2002. It seems that they had similar astro-nomical conditions and the best was in 1982. The studies about the effect of tide on the global climate… 相似文献
13.
圆盘固相萃取富集-气相色谱法测定地表水中有机氯和有机磷农药 总被引:4,自引:2,他引:2
采用环境友好的圆盘固相萃取新技术富集水体中有机氯农药和有机磷农药,分别用微池电子捕获检测器(μECD)和火焰光度检测器(FPD)气相色谱法检测,实现了水中有机氯和有机磷农药残留物的测定。结果表明,16种有机氯农药的平均回收率为64.7%~102%,精密度(RSD,n=6)为2.9%~15%;13种有机磷农药的平均回收率为65.9%~104%,精密度(RSD,n=6)为1.7%~17%。方法快速、灵敏、低污染,可用于水体中多种有机氯农药和有机磷农药的残留分析。 相似文献
14.
This paper presents an example of application of the double solid reactant method (DSRM) of Accornero and Marini (Environmental
Geology, 2007a), an effective way for modeling the fate of several dissolved trace elements during water–rock interaction. The EQ3/6 software
package was used for simulating the irreversible water–rock mass transfer accompanying the generation of the groundwaters
of the Porto Plain shallow aquifer, starting from a degassed diluted crateric steam condensate. Reaction path modeling was
performed in reaction progress mode and under closed-system conditions. The simulations assumed: (1) bulk dissolution (i.e.,
without any constraint on the kinetics of dissolution/precipitation reactions) of a single solid phase, a leucite-latitic
glass, and (2) precipitation of amorphous silica, barite, alunite, jarosite, anhydrite, kaolinite, a solid mixture of smectites,
fluorite, a solid mixture of hydroxides, illite-K, a solid mixture of saponites, a solid mixture of trigonal carbonates and
a solid mixture of orthorhombic carbonates. Analytical concentrations of major chemical elements and several trace elements
(Cr, Mn, Fe, Ni, Cu, Zn, As, Sr and Ba) in groundwaters were satisfactorily reproduced. In addition to these simulations,
similar runs for a rhyolite, a latite and a trachyte permitted to calculate major oxide contents for the authigenic paragenesis
which are comparable, to a first approximation, with the corresponding data measured for local altered rocks belonging to
the silicic, advanced argillic and intermediate argillic alteration facies. The important role played by both the solid mixture
of trigonal carbonates as sequestrator of Mn, Zn, Cu and Ni and the solid mixture of orthorhombic carbonates as scavenger
of Sr and Ba is emphasized.
相似文献
Luigi Marini (Corresponding author)Email: |
15.
Shear strength characterization of municipal solid waste at the Suzhou landfill, China 总被引:5,自引:0,他引:5
The current practice of slope stability analysis for a municipal solid waste (MSW) landfill usually overlooks the dependence of waste properties on the fill age or embedment depth. Changes in shear strength of MSW as a function of fill age were investigated by performing field and laboratory studies on the Suzhou landfill in China. The field study included sampling from five boreholes advanced to the bottom of the landfill, cone penetration tests and monitoring of pore fluid pressures. Twenty-six borehole samples representative of different fill ages (0 to 13 years) were used to perform drained triaxial compression tests. The field and laboratory study showed that the waste body in the landfill can be sub-divided into several strata corresponding to different ranges of fill age. Each of the waste strata has individual composition and shear strength characteristics. The triaxial test results showed that the MSW samples exhibited a strain-hardening and contractive behavior. As the fill age of the waste increased from 1.7 years to 11 years, the cohesion mobilized at a strain level of 10% was found to decrease from 23.3 kPa to 0 kPa, and the mobilized friction angle at the same strain level increasing from 9.9° to 26°. For a confinement stress level greater than 50 kPa, the shear strength of the recently-placed MSW seemed to be lower than that of the older MSW. This behavior was consistent with the cone penetration test results. The field measurement of pore pressures revealed a perched leachate mound above an intermediate cover of soils and a substantial leachate mound near the bottom of the landfill. The measurements of shear strength properties and pore pressures were utilized to assess the slope stability of the Suzhou landfill. 相似文献
16.
Mihoko Hoshino Mitsuyoshi Kimata Norimasa Nishida Masahiro Shimizu 《Physics and Chemistry of Minerals》2008,35(2):59-70
Dissakisites from Trimouns dolomite mine, France, have two kinds of single crystals: chemical-zoned and homogeneous types.
Back-scattered electron microprobe (BSE) images of these dissakisites reveal both Ca–Al rich dark zones and Fe-ΣREE rich bright
zones. Crystal structures of three dark and two bright zones in a chemical-zoned dissakisite and of a homogeneous zone in
unzoned dissakisite were refined to individual R indices (about 3.0–5.0%) based on 1,400 observed [|F
0| > 4σF
0] reflections measured with MoKα X-radiation using the single crystal diffractometer. The differences in brightness between
their BSE images arise from those in coupled substitutions of the elements occupying A2 and M3 sites. The main reason for
these differences is that ten-coordinated A2 polyhedra and M3 octahedra are directly linked through their shared edge, which
creates a great potential for making this coupled substitution. This zoning indicates that formation of the whole zoned crystal,
where each zone could be grown steadily with its crystallographic axes mutually parallel to each other, may be identified
as autoepitaxy. 相似文献
17.
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19.
韩宗珠 《中国海洋大学学报(自然科学版)》1989,(4)
本文首次对我国石榴石橄榄岩类岩石进行系统的岩石学和地球化学研究。通过对大别山地区两个不同类型岩体中的石榴石橄榄岩的岩石学、岩石化学、矿物化学和稀土元素地球化学研究,表明这类岩石属钙碱性系列超基性岩;与地幔成分相比,富集易熔元素,亏损难熔元素;利用矿物地质温压计估算其形成压力为2×10~9pa,成岩温度为600~700℃具有正铕异常和轻稀土元素富集特征 推测为地壳下部的超基性岩经深成变质而成。 相似文献
20.