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1.
以93%的盱眙凹凸棒和临泽凹凸棒为载体,淀粉糖苷非离子表面活性剂为分散剂,负载纳米氧化铁为活性组分制备脱硫剂。采用L18(2×73)正交试验和单因素试验,对气体流量为10ml/min的纯H2S气体,在不同条件下制备的脱硫吸附剂进行H2S气体脱除研究。结果表明:得到的纳米氧化铁为各种晶态型氧化铁,纳米氧化铁分散均匀,且其平均粒径小于10nm,脱除H2S的最大硫容为29.98%。利用红外(IR)、X射线衍射(XRD)、透射电镜(TEM)和X射线光电子能谱(XPS)等技术对脱硫反应前后的脱硫剂进行表征并分析其脱硫机理。  相似文献   
2.
大气沙尘气溶胶中铁氧化物含量的测定对研究气溶胶吸收特性有重要的研究意义。采用柠檬酸盐-重碳酸盐-连二亚硫酸盐(CBD)和漫反射光谱法(DRS)对塔克拉玛干沙漠腹地塔中站2006年4月9~11日沙尘暴天气过程前后TSP沙尘样品中的游离氧化铁进行定量和半定量研究,研究得出,塔中游离氧化铁占全铁含量的变化范围在4.55%~8...  相似文献   
3.
不同成因类型铁矿石中氧化铁矿物的化学成分和晶体结构存在一定程度的差异。光学显微镜和电子探针分析可以有效地识别铁矿石中氧化铁矿物的形貌与成分,激光拉曼光谱可深入探讨其晶体结构以及微观区域(1~100μm)的相变特征。  相似文献   
4.
长江口沉积物对铅的吸附作用   总被引:9,自引:2,他引:7  
模拟研究长江口悬浮沉积物对Pb的吸附作用,发现沉积物的吸附性能与其氧化铁和有机物等活性组份的含量密切相关,获得Langmuir型吸附等温线,测定饱和吸附容量和分配系数,结果表明,pH和盐度对吸附产生明显影响,吸附率与pH和盐度之间分别呈线性正相关和负相关关系。初步探讨吸附动力学特征,沉积物对Pb吸附化化学作用为主,与厦门港沉积物相似。  相似文献   
5.
The adsorption behaviors of Cr(VI) on laterite from Guizhou Province were studied in this paper, and the adsorption mechanism was discussed as well. Results showed that different mineral compositions in the laterite would cause differences in the capacity of laterite to absorb Cr(VI). Gibbsite, iron oxide minerals and non-crystalloids are the main contributors to enhancing the capacity of laterite to absorb Cr(VI). The pH of the solution is an important factor affecting the adsorption of Cr(VI) on laterite. Acidic environment (pH=2–5) is favorable to the adsorption of Cr(VI). The amount of adsorbed Cr(VI) decreases with increasing pH of the solution. With increasing initial concentrations of Cr(VI), the amount of adsorbed Cr(VI) increases first, and then decreases. The optimal adsorption concentration of Cr(VI) on laterite is 250 μg/mL. The adsorption of Cr(VI) on laterite is a rapid process, about 80% Cr(VI) will be adsorbed within 2 hours. And the adsorption of Cr(VI) on kaolinite is a slow process.  相似文献   
6.
Nine species of Prionospio complex are recorded from China’s waters, including one new species and six newly recorded species. Prionospio (Prionospio) pacifica sp. nov., is characterized by having first and forth pairs of branchiae pinnate, second and third pairs of apinnate, ventral crest on Setiger 9 and dorsal crests on Setigers 10—25. Apoprionospio kirrae (Wilson, 1990), Prionospio (Aquilaspio) convexa Imajima, 1990, Prionospio (Minuspio) multibranchiata Berkeley, 1927, Prionospio (Prionospio) bocki Sderstrm, 1920, Prionospio (Prionospio) dubia Maciolek, 1985 and Prionospio (Prionospio) paradisea Imajima, 1990 are recorded for the first time from China’s waters.  相似文献   
7.
8.
1.This paper deals with a discovery of ours-a new type of isotherm in seawater systems, which cannot be represented by the adsorption isotherm equation available at present in marine chemistry. It has two characteristics as follows: (I) the non-linear relationship between the ion exchanged amount of particulate matter and the equilibrium concentration in the initial low concentration portion of the curve, showing instead an exponental function with slight concave upward. (2) the isotherm is made up of two “S shape” curves, which intersect each othernear the middle, with one “Knee” and two“Plateaus” at the intersection.  相似文献   
9.
Adsorption of arsenate on hydrous iron oxide is an important process controlling geochemical cycling of arsenic in environment as well as the fate of arsenic-bearing mining wastes. The widely accepted view on the mechanism of adsorption is that arsenate is adsorbed via bidentate binuclear inner-sphere complexation. In this study, we characterized the arsenate-hydrous iron oxide sorption solids synthesized at pH=3-8 using Fourier transformed infrared spectroscopy (FTIR) and X-ray diffraction (XRD). It has been determined that poorly crystalline ferric arsenate developed on the surface of iron oxide when arsenate was sorbed at acidic pH, while at alkaline pH the adsorption of arsenate was via bidentate complexation.  相似文献   
10.
Clementine UVVIS and NIR data from the lunar sampling sites (totaling 46 sampling sites) were processed and used to refine the iron determination method of Le Mouéic et al. (2000, 2002). We found that about 21 sampling sites are unsuitable to Le Mouéic et al's spectral parameters ("slope" and "depth l") because their 1500 nm filter could not be used as spectral parameters' right shoulders and to evaluate the depth of the 1-μm absorption feature accurately. We used the rest 25 sampling sites to refine the method developed by Le Mouéic et al. (2000, 2002 ) and obtained our own equation of FeO content determination. We tested our own equation, and the results are satifactory. In our work we also acquired some useful experiences in scientific applications of our own dataset of the Chang'E-1 mission.  相似文献   
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