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201.
Yanying SUN Fei LIU Honghan CHEN Wei HE 《中国地球化学学报》2006,25(B08):126-127
The treatment of diesel-contaminated soil with hydrogen peroxide oxidation is investigated in this paper. The factors influencing reactions such as initial oil content, H2O2 dosage, pH-value, catalyst and so on are studied. The results indicate that it is feasible to remediate diesel-contaminated soil by adding oxidant directly at room temperature because of higher absolute removal content although the degradation efficiency is low for the contaminated soil of 1%, 2% and 5% initial oil content. The more the H2O2 dosage, the better the degradation efficiency; it is economical and efficient to add 4 mL H2O2 to 10 g diesel-contaminated soil (2% or so) directly in-situ chemical oxidation (ICO). For the contaminated soil of 5% initial oil content, when pH-value is 5-8 and H202 dosage is 20 mL, the removal efficiency reaches more than 96%; when pH-value is 1-3 and volume ratios of H2O2 to Fe^2+ are 1 : 1, 2:2, the degradation efficiencies are all very high (i.e., 86%-88% or so). It can be concluded that the degradation efficiencies are comparative when adding 1 mL or 2 mL H2O2 of Fenton Reagent or adding 4 mL of H2O2 only to 10 g diesel-contaminated soil. 相似文献
202.
胶东金矿成矿流体同位素的地质特征 总被引:13,自引:0,他引:13
胶东大、中型金矿床成矿流体的H、O同位素组成显示出金矿床的初生成矿流体以岩浆水为主,在重熔花岗岩形成作用中继承了部分变质水,在高温阶段的成矿作用中以岩浆水为主,其后逐渐向大气降水方向演化,只有少部分矿床属大气降水成因。本文探讨了H.P.泰勒的水岩反应同位素交换质量平衡方程的应用条件,当水/岩比很小时,该方程不能确切判定关于成矿流体的成因,本文提供了以地质条件为前提的解析方法。成矿流体的Rb-Sr年龄揭示出胶东金矿主要成矿期为燕山晚期,成矿流体的ISr与玲珑花岗质杂岩体中的郭家店、郭家岭型岩体一致,而成矿作用特别是与郭家岭型岩体重熔形成作用有关。 相似文献
203.
VMS矿床成矿流体的组成,来源及作用机制 总被引:5,自引:1,他引:5
VMS矿床是一类非常重要的有色金属矿床,其成因与火山岩及海水密切相关。流体包裹体成分及氢氧同位素特征表明成矿流体主要为加热的海水,可能有岩浆水的参与。渗入火山岩层的海水在深部热源作用下发生对流,并萃取了火山岩中的金属。成矿流体在海底喷溢,与海水混合反应,造成矿石沉淀。整个成矿演化过程经历了复杂的流体—岩石反应和流体—流体反应,这些反应在成矿中起着非常重要的作用。 相似文献
204.
催化动力学光度法测定痕量钛的研究 总被引:2,自引:0,他引:2
在氨性介质中,痕量Ti(Ⅳ)催化KIO4氧化靛红的褪色反应。褪色程度与Ti(Ⅳ)的浓度在0~8μg/L线性相关;对于靛红褪色反应为零级,对于Ti(Ⅳ)该反应为一级;测定该反应的表观活化能为7045kJ/mol;反应速率关系式是-dCR/dt=KCTi。基于该反应,建立测定痕量Ti的方法,其检出限505×10-9g/L;RSD(n=6)<52%,干扰可经伯胺N1923萃取分离消除。方法用于人发样中痕量Ti(Ⅳ)的测定,结果与极谱法相符。 相似文献
205.
根据反应:2石榴子石(Gt)+3石英(Q2)=2斜方辉石(Opx)+堇青石(Cord),采用最新热力学资料,在平衡热力学原理的基础上,建立该反应Mg、Fe端员组分压力计表达式:经世界典型孔兹岩系地区的验证以及与其它石榴子石一墓青石压力计对比,计算结果基本合理,表明这一新的压力计具有较好的应用价值。 相似文献
206.
河北平原浅层地下水地球化学演化模拟 总被引:2,自引:0,他引:2
反应路径模拟技术是近十几年发展起来的定量研究地下水地球化学演化的重要方法。文中讨论了反应路径模拟与质量平衡模拟的差异,提出了对复杂水流系统采取分段模拟,以及对浅层成水形成的主要作用即蒸发浓缩作用和海侵的影响采用土壤盐类综合体的溶解来表征的处理方法,论述了研究区浅层地下水的地球化学演化过程。 相似文献
207.
Two kinds of mylonite series rocks, felsic and mafic, have been recognized in the NW-striking shear zone of the Jiapigou gold
belt. During ductile deformation, a large amount of fluid interacted intensively with the mylonite series rocks: plagioclases
were sericitized and theAn values declined rapidly, finally all of them were transformed to albites; dark minerals were gradually replaced by chlorites
(mostly ripidolite). Meanwhile, large-scale and extensive carbonation also took place, and the carbonatization minerals varied
from calcite to dolomite and ankerite with the development of deformation. The δ13C values of the carbonates are −3.0‰ – −5.6‰ suggesting a deep source of carbon. The ductile deformation is nearly an iso-volume
one (f
v≈1). With the enhancement of shear deformation, SiO2 in the two mylonite series rocks was depleted, while volatile components suchs as CO2 and H2O, and some ore-forming elements such as Au and S were obviously enriched. But it is noted that the enrichment of Au in both
the mylonite series rocks did not reach the paygrade of gold. The released SiO2 from water-rock interactions occurred in the form of colloids and absorbed gold in the fluid. When brittle structures were
formed locally in the ductile shear zone, the ore-forming fluids migrated to the structures along microfractures, and preciptated
auriferous quartz because of reduction of pressure and temperature. Fluid inclusion study shows that the temperature and pressure
of the ore-forming fluids are 245–292°C and 95.4–131.7 MPa respectively; the salinity is 12.88–16.33wt% NaCl; the fluid-phase
is rich in Ca2+, K+, Na+, Mg2+, F− and Cl−, while the gaseous phases are rich in CO2 and CH4. The δD and δ18O, values of the ore-forming fluid are −84.48‰ – −91.73‰ and −0.247‰ – +2.715‰ respectively, suggesting that the fluid is
composed predominantly of meteoric water.
This project is financially supported by the National Natural Science Foundation of China (No. 9488010). 相似文献
208.
The design and performance of a smog chamber for the study of photochemical reactions under simulated environmental conditions is described. The chamber is thermostated for aerosol experiments, and it comprises a gas chromatographic sample enrichment system suitable for monitoring hydrocarbons at the ppbv level. By irradiating NO
x
/alkane-mixtures rate constants for the reaction of OH radicals with n-alkanes are determined from n-pentane to n-hexadecane to be (k±2)/10–12 cm3 s–1=4.29±0.16, 6.2±0.6, 7.52 (reference value), 8.8±0.3, 10.2±0.3, 11.7±0.4, 13.7±0.3, 15.1±0.5, 17.5±0.6, 19.3±0.7, 22.3±1.0, and 25.0±1.3, respectively at 312 K. Rate constants, (k±2)/10–17 cm3 s–1, for the reaction of ozone with trans-2-butene (21.2±1.0), cis-3-methylpentene-(2) (47.2±1.7), cyclopentene (62.4±3.5), cyclohexene (7.8±0.5), cycloheptene (28.3±1.5), -pinene (8.6±1.3), and -pinene (1.4±0.2) are determined in the dark at 297 K using cis-2-butene (13.0) as reference standard. 相似文献
209.
化学动力学在地球化学中的某些应用 总被引:2,自引:0,他引:2
Shi Pingfang Yu Chongwen 《地球科学》1986,(4)
化学动力学在地球化学(特别是成矿作用地球化学)研究中有极其重要的作用,其主要应用包括七个方面。本文重点介绍了地球化学中化学动力学的实验研究方法以及碳酸盐、硅酸盐、氧化物和硫化物等矿物的反应动力学实验成果;介绍了Helgeson的质量迁移理论及其研究热液在围岩中的运移方面的应用,并在热力学性质和动力学行为两方面研究了围岩的离解作用、蚀变作用与矿化作用及其相互关系。 相似文献
210.
Glaucophane and pyroxene breakdown reactions in the Pennine units of the Eastern Alps 总被引:1,自引:0,他引:1
Abstract New occurrences of crossite and jadeitic pyroxene are described from a thick metabasite unit within the upper levels of the Peripheral Schieferhülle in the Tauern Window, Austria. Unusual textures are preserved which provide evidence for the reactions and mechanisms involved in the breakdown of crossite and jadeitic pyroxene. Zones of albite and chlorite, produced by reaction between crossite and paragonite, have been preserved due to sluggish reaction kinetics during decompression from the blueschist to the greenschist facies. The zonal sequence is interpreted in terms of chemical potential gradients in Na, Mg and Al, which have been established by overstepping the equilibrium boundary. Breakdown textures of jadeite-acmite pyroxene to a symplectite of albite + hematite + actinolite, and of crossite to talc and actinolite are also described.
The occurrence of crossite and jadeitic pyroxene at high levels within the Peripheral Schieferhülle implies that even upper levels of the structural sequence have undergone blueschist facies metamorphism with pressures in excess of 8 kbar during the Alpine collisional event. 相似文献
The occurrence of crossite and jadeitic pyroxene at high levels within the Peripheral Schieferhülle implies that even upper levels of the structural sequence have undergone blueschist facies metamorphism with pressures in excess of 8 kbar during the Alpine collisional event. 相似文献