Dispersion performance of nanoparticles in water          下载免费PDF全文

MA Li-sha  HAN Zhan-tao  WANG Yan-yan 《地下水科学与工程》2021,9(1):37-44

Engineering Nanoparticles(ENPs)’superior characteristics of adsorption depends on their dispersion in the medium.In this study,multi-walled carbon nanotubes(nonmetal),iron nanoparticles and silver nanoparticles(metallic simple substance),and Nano-TiO2,Nano-Fe2O3 and Nano-ZnO(metal oxide)were selected and respectively added into pure water and aqueous solution with 1%Sodium dodecyl benzene sulfonate(SDBS)surfactant.The dispersion effects were compared by leaving the solutions standing at room temperature under ultrasound.The results show that the dispersion of iron nanoparticles is the lowestamong the six ENPs,and that of multi-walled carbon nanotubes(MWCTS)is the highest.Adding anionic surfactants(SDBS)can obviously improve the dispersion performance of ENPs.The concentration of solution decreases by only 5%in 10 daysafter adding 1%SDBS for ultrasonic dispersion.  相似文献   

Theoretical analyses of acidization dissolution front instability in fluid‐saturated carbonate rocks     

Chongbin Zhao  B. E. Hobbs  A. Ord 《国际地质力学数值与分析法杂志》2013,37(13):2084-2105

This paper presents an instability theory that can be used to understand the fundamental behavior of an acidization dissolution front when it propagates in fluid‐saturated carbonate rocks. The proposed theory includes two fundamental concepts, namely the intrinsic time and length of an acidization dissolution system, and a theoretical criterion that involves the comparison of the Zhao number and its critical value of the acidization dissolution system. The intrinsic time is used to determine the time scale at which the acidization dissolution front is formed, while the intrinsic length is used to determine the length scale at which the instability of the acidization dissolution front can be initiated. Under the assumption that the acidization dissolution reaction is a fast process, the critical Zhao number, which is used to assess the instability likelihood of an acidization dissolution front propagating in fluid‐saturated carbonate rocks, has been derived in a strictly mathematical manner. Based on the proposed instability theory of a propagating acidization dissolution front, it has been theoretically recognized that: (i) the increase of the mineral dissolution ratio can stabilize the acidization dissolution front in fluid‐saturated carbonate rocks; (ii) the increase of the final porosity of the carbonate rock can destabilize the acidization dissolution front, while the increase of the initial porosity can stabilize the acidization dissolution front in fluid‐saturated carbonate rocks; (iii) the increase of the mineral dissolution ratio can cause an increase in the dimensionless propagation speed of the acidization dissolution front; (iv) the increase of the initial porosity can enable the acidization dissolution front to propagate faster, while the increase of the final porosity can enable the acidization dissolution front to propagate slower in the acidization dissolution system. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

我国首次发现的钠砷铀云母   总被引：1，自引：0，他引：1  

张静宜 《铀矿地质》1988,(5)

我国首次发现的钠砷铀云母产于新疆某铀矿床氧化带。它实际上是钠砷铀云母的含钾变种。与产于苏联的钠砷铀云母比较,晶胞参数稍大,比重稍小,在长波紫外线照射下发黄绿色中等强度荧光。  相似文献   

活性炭柱分离－亚硫酸钠解吸萃取比色法测定痕量金     

刘汉初  倪桃英 《铀矿地质》1988,(2)

本文叙述了用活性炭色层柱分离、亚硫酸钠解吸、TMK-异戊醇萃取比色测定痕量金的方法。采用了以硫酸钴、铬酸钾和硫酸铜等无机盐配制模拟标准系列,可以长期使用。本法操作简单,快速,成本低,工效高。一人一天可以分析30个以上试样,能测定出1×10~(-3)ppm的金含量,适用于地质普查金矿中大批试样的分析。  相似文献   

我国首次发现的纤碳铀矿     

王爱珍  张静宜 《矿物学报》1988,(3)

本文报道的纤碳铀矿产于湖南某花岗岩型铀矿床氧化带中。纤碳铀矿是一种铀酰碳酸盐矿物,在中国是首次发现。本文作了系统的矿物研究并与国外资料作了对比。  相似文献   

Bauxite development in the North Apuseni mountains, western Romania     

Georgeta E. Ionescu 《Cretaceous Research》1993,14(6)

The stratigraphic and palaeogeomorphologic conditions of bauxite formation in the North Apuseni mountains are related to the geotectonic evolution of western Romania during the Late Jurassic and Early Cretaceous. Bauxitization, accumulation and preservation of the bauxites were directly associated with karst development in the area under study. The petrographic and mineralogic nature of the bauxite deposits reveal superimposed aliagenetic, catagenic and, locally, metamorphic features. A comparative analysis of the principal chemical components of the different bauxite-bearing zones of the North Apuseni mountains are used to show similar development.  相似文献   

广西灌阳地区碳酸盐岩层滑断裂构造地球化学系统   总被引：10，自引：1，他引：10  

钱建平 《矿物学报》1994,14(4):348-356

灌阳地区碳酸盐岩中的层滑断裂构造地球化学系统具有典型的结构分带性、变形二重性和成分互补性。在这个系统中存在着Cu→Fe3 →V→Si→Al→Mn→Ba→Ni→Sr→Ag→Bi→Ga→In→Pb→Fe2 →Cr→Co→Zn→Mg→Ca→CO2的稳定性递减序列。影响构造地球化学分异的因素是原岩的性质、应力、温度和流体。构造地球化学作用的基本类型有：动力分异作用、压溶作用和氧化还原作用。层滑断裂带并非还原环境，碳质富集源自有机碳的氧化。Sr是高应力环境同构造重结晶方解石带的特征元素，Zn是低应力环境裂隙充填型方解石脉的特征元素。  相似文献   

碳硅泥岩型铀矿床的成矿作用与红层（盆）的关系   总被引：2，自引：0，他引：2  

连立祥 《华东地质学院学报》1994,17(1):68-75

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Organic geochemical studies of a recent Inner Great Barrier Reef sediment—I. Assessment of input sources     

Philip M. Shaw  R.B. Johns 《Organic Geochemistry》1985,8(2):147-156

The concentration of solvent-extractable (SE) and bound hydrocarbons, ketones, alcohols, sterols, monocarboxylic acids, hydroxyacids and α,ω-dicarboxylic acids of a surface sample (0–2.5 cm) from a recent carbonate tropical sediment taken at 60ft (18m) depth north-west of the Low Isles, North Queensland, are reported in detail. n-Alkanes are a minor constituent in the SE and bound hydrocarbon fractions with the major component being unresolved complex hydrocarbon material which is not an anthropogenic input. 6,10,14-Trimethylpentadecan-2-one derived from chlorophyll, as well as phytol, were identified as major components of the ketone and alcohol constituents. No chlorophyll pigments or pigmented degradation products were present, implying degradation before incorporation into the sediment. This conclusion is consistent with evidence for higher-plant input in which all sensitive lipids have been degraded before incorporation. SE and bound fractions have been studied in detail and show considerable differences probably arising from the importance of viable biomass in the SE fraction. Inputs to the sediment are determined as higher plants, algae, bacteria, fungi and meiofauna in descending order of importance.  相似文献   

Infrared estimates of aliphatic kerogen carbon in sedimentary rocks     

H.J. Schenk  E.G. Witte  P.J. Müller  K. Schwochau 《Organic Geochemistry》1986,10(4-6)

An infrared routine has been developed to estimate the aliphatic portion of kerogen carbon in sedimentary rocks. The procedure does not require isolation of the organic matter and is based on a computer-assisted determination of global band areas in the region of the aliphatic carbon-hydrogen stretching vibrations around 2900cm⁻¹. From these integrated absorptions the amount of aliphatic carbon C_al (mg of aliphatic carbon per gram of solvent-extracted rock) is calculated by means of a calibration with model rocks. Carbonate overtones which interfere in the case of limestones are eliminated by comparison to a CaCO₃ standard.The method has been applied to rocks containing kerogens of different types and maturities at TOC levels of 0.5 to 12%. The aliphatic carbon concentrations range from 0.5 to 60mg·g⁻¹ and correlate reasonably well with the residual genetic potentials of the rocks as measured by S₂ values from Rock-Eval pyrolysis. The ratio S₂/C_al is found to decrease with burial depth reflecting a maturity enhanced conversion of aliphatic carbon to fixed aromatic carbon under Rock-Eval conditions.  相似文献