红壤中非吸附性离子水平运移特征试验研究

以南方第四纪红壤为研究对象,以KBr溶液为示踪剂,采用水平土柱入渗法研究不同土壤前期含水量和入渗液浓度条件下非吸附性离子溴在红壤中的水平运移特征。结果表明,浓度梯度和水势梯度分别在水平入渗的初期和后期阶段起主导作用;Br-整体水平运移速率与入渗液浓度之间基本存在正相关关系,土壤前期含水量的不同,入渗液浓度对溴离子运移速率的影响程度各异;土壤前期含水量的提高促进了Br-的运移,同时也揭示了当浓度梯度一定时,水势梯度的变化直接影响湿润锋及Br-的运移。

非吸附性离子质量浓度对红壤入渗特性的影响

为了研究非吸附性离子(以Cl^-为例)的质量浓度变化对红壤水分运动溶质迁移特性及分布规律的影响,通过一维垂直入渗法,并借助于HYDRUS模型对其进行了模拟.结果表明:初始Cl^-质量浓度对红壤湿润锋推进和入渗能力有较强的影响,初始Cl^-质量浓度越大湿润锋推进越快,累积入渗量和稳定入渗率也相应地增加,但在入渗开始初期100 min内这种影响不显著.初始Cl^-质量浓度也影响了入渗结束后土体内含水率和Cl^-含量的分布,同一土层深度含水率与Cl^-含量随初始质量浓度的增加而变大.HYDRUS模型对不同浓度下的红壤水分Cl^-入渗及分布模拟平均相对误差在9.3%以内,模拟效率系数(NSE)均在0.85以上,模型的适应性较好.研究结果可为红壤区水肥一体化灌溉水分溶质运移研究提供指导.

非吸附型反应性粉体二氧化氯消毒剂

二氧化氯是一种广谱高效、安全无毒的消毒剂,可用作高效杀菌消毒剂、水处理剂、漂白剂、食品保鲜剂以及用来降解农药和多环酚烃等环境中难以降解的物质。

IN SITU IMAGING OF BREAST CANCER CELLS USING GREEN SEMICONDUCTOR QUANTUM DOTS

The breast cancer is the most common cause of cancer death in women. To establish an early stage in situ imaging of breast cancer cells, green quantum dots （QDs） are used as a fluorescent signal generator. The QDs based imaging of breast cancer cells involves anti-HER2/neu antibody for labeling the over expressed HER2 on the surface of breast cancer cells. The complete assay involves breast cancer cells, biotin labeled antibody and streptavidin conjugated QDs. The breast cancer cells are grown in culture plates and exposed to the biotin labeled antibodies, and then exposed to streptavidin labeled QDs to utilize the strong and stable biotin-streptavidin interaction. Fluorescent images of the complete assay for breast cancer cells are evaluated on a microscope with a UV light source. Results show that the breast cancer cells in the complete assay are used as fluorescent cells with brighter signals compared with those labeled by the organic dye using similar parameters and the same number of cells.

Velocity of a Liquid Drop with a Sorption-Controlled Surfactant

The terminal velocity of a liquid droplet settling in a sulfactant solution has been studied for the non-linear adsorption Langmuir frameworks accounting for monolayer saturation and non-ideal surfactant interactions. Most prior research uses a linear adsorption model which cannot capture these effects, The Maragoni migration of a liquid drop settling through a surfactant solution is examined by using Langmuir framework. The solution concentration Ceq is assumed large enough for the surfactant mass transfer to be adsorption-controlled. Langmuir model generates non-linear Marangoni stresses which diverge in the limit of approaching ∝, strongly retarding U'.

Effect of Temperature Variation on the Separation of Sesamin and Sesamolin by Simulated Moving Bed

In this work, sesamin and sesamolin is separated and purified by SMB （simulated moving bed） chromatography. Purity of sesamin and sesamolin can reach 99.2% and 99.9 %, and they can be recovered by 99.9% and 99.4%, respectively. Concentrations of the extract and raffinate was monitored and periodical change of the concentration was observed on experiment. Effects of non-linear adsorption, dead volume, and temperature on the separation are reviewed by the triangle theory to explain the periodical change of concentration. It is found that dead volume has little effect, and temperature fluctuation significantly affects thc separation by SMB. The temperature seriously affects the robust operation of SMB due to the change of Henry＇s constant, which will change the selectivity and restrain the productivity. Although the productivity in this study is only 0.0416 g/L-hr, the cost of the stationary phase used in this study is much lower than that of packed in analytical column. By using this stationary phase, the authors are still able to separate the mixture of sesamin and sesmolin. This will economically attract attention for the application of SMB to purify bioactive compounds on developing botanical drugs.

Heavy metals adsorption by banana peels micro-powder: Equilibrium modeling by non-linear models

In this study the copper and lead adsorption efficiency onto banana peels powder was investigated. The agroindustrial waste recovery represents one of the Circular Economy pillars. In the view of the synthesis of an environmentally friendly adsorbent material, the powder was used without any preliminary chemical or thermal activation, but only after simple washing, drying and grinding. The bio-adsorbent was characterized by the FTIR technique and tested in batch mode on synthetic aqueous solutions containing Pb and Cu in the range 10–90 mg·L^(-1). A selection of two(Langmuir, Freundlich) and three(Sips, Redlich–Peterson, Koble–Corrigan) parameter isotherm models was chosen to fit adsorption equilibrium data by non-linear regression procedure. The best fit isotherm model was selected relying on the error function with the lowest average percentage error(APE) value, among those characterized by the highest R^2 values. As expected, the three-parameter models are found to better represent both metals bio-adsorption, with APE and R^2 values always lower and higher, respectively, than the corresponding values obtained for the two-parameter models.

Effects of Non-specific and Specific Solvation on Adsorption of BPTI on Au Surface： Insight from Molecular Dynamics Simulation

Proteins adsorption at solid surfaces are of paramount important for many natural processes. However, the role of specific water in influencing the adsorption process has not been well understood. We used molecular dynamics simulation to study the adsorption of BPTI on Au surface in three water environments （dielectric constant model, partial and full solvation models）. The result shows that a fast and strong adsorption can occur in the dielectric environment, which leads to significant structure changes, as confirmed by great deviation from the crystal structure, largely spreading along the Au surface, rapid lose in all secondary structures and the great number of atoms in contact with the surface. Compared to the dielectric model, slower adsorption and fewer changes in the calculated properties above are observed in the partial solvation system since the specific water layer weakens the adsorption effects. However, in the partial solvation system, the adsorption of polar Au surface causes a significant decrease in the specific hydration around the protein, which still results in large structure changes similar to the dielectric system, but with much less adsorption extent. Enough water molecules in the full solvation system could allow the protein to rotate, and to large extent preserve the protein native structure, thus leading to the slowest and weakest adsorption. On the whole, the effects of non-specific and specific solvation on the protein structure and adsorption dynamics are significantly different, highlighting the importance of the specific water molecule in the protein adsorption.

Sorption behavior of coal for implication in coal bed methane an overview

CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of greenhouse gases and the emerging commercial significance of CBM. Reservoir-simulation technology,as a useful tool of reservoir development, has the capability to provide us with an economic means to solve complex reservoir-engineering problems with efficiency. The pore structure of coal is highly heterogeneous, and the heterogeneity of the pores depends on the coal type and rank.

Adsorption of Naphthol Green B on unburned carbon：2-and3-parameter linear and non-linear equilibrium modelling

The study deals with adsorption of Naphthol Green B on two unburned carbons and the parent coal,from which the UCs have been created in a fluidised-bed power station.Particular attention has been paid to the adsorption equilibrium modelling:experimental data has been analysed using 2-parameter(Langmuir,Freundlich) and3-parameter(Redlich-Peterson) isotherms — both linear and non-linear regressions have been used for the estimation of the isotherm parameters.In the case of both UCs,the Langmuir isotherm model provides the worst fit,whereas 2-parameter Freundlich and 3-parameter Redlich-Peterson models are both good,from which 3-parameter Redlich-Peterson isotherm provides slightly better results(despite the penalty used for the higher number of parameters).In the case of both UCs,the linear regression of Freundlich and Redlich-Peterson models provides good results(comparable with non-linear regressions).Unlike both UCs,the best fit of the experimental data from the adsorption on the coal has been achieved by the Langmuir isotherm model.The results based on the Freundlich or Redlich-Peterson model were(in this case) somewhat worse.

State of Pepsin and Acidic Protease in Solid Phase System and the Factors Increasing Their Destabilization

The adsorption state and catalytic properties of pepsin and acidic protease from microorganisms Asp. awamori and Asp. oryzae were studied in solid phase system （in presence of sorsilen, DEAE- and CM-cellulose）. According to the results, adsorption capacity and catalytic activity of enzymes depend on the physical nature of surface groups of the solid phase. Changing the stability of enzymes in the system with solid phase is observed even the adsorption bond is less stable （in the case of DEAE- and CM-cellulose in acidic media）. Injection to the medium ethanol, surfactants, sodium chloride and changing the temperature of the incubation medium could prevent the negative effects of the solid phases. When sorsilen is used as solid phase, pepsin and acidic protease from Asp. awamori suffer from high surface inactivation. Various surfactants influence adsorption state of enzymes differently. Non-ionic surfactants （Triton X-100） prevent adsorption and restore catalytic properties of enzymes.

初始含水量对黄河口潮滩溶质优先运移的影响研究

陆源污染物在潮滩沉积物中的迁移吸附对海洋生态环境有重要影响。选取非吸附性溶质NO3-和吸附性溶质H2PO4-作为示踪剂,通过室内土柱实验研究三种初始含水量对黄河口沉积物中非吸附性溶质和吸附性溶质优先运移的影响。结果表明,干土条件使得大孔隙对水流和溶质运移的贡献更大,初始穿透更早,相对浓度峰值更大,回收率更高;随着黄河口沉积物初始含水量增高,大孔隙和基质相互作用增强,对溶质的吸附效果增加,尤其是对H2PO4-的吸附效果非常明显,减少了污染物向海洋的输送。