环境监测分析中校准曲线应用和检验方法的探讨

本文阐述了环境监测分析中校准曲线的分类 ,拟合方法和应用范围 ,提出对拟合标准曲线可靠性检验的概念和方法。如 :相对剩余标准差 ,截距、斜率检验 ,失拟方差检验等 ,这些方法在实际监测分析中具有一定的应用价值     

一种研究絮凝过程的新方法——透光脉动检测技术

采取电解法制备聚合絮凝剂可望通过控制过程的电化学与溶液化学条件，克服化学法制备中的缺陷，以获取最优的絮凝剂形态和效果。极化是影响电解制备的最主要问题之一。它将产生过电位，增加电解槽压，降低电流效率。     

Excel软件在石化环境监测质量控制中的应用

应用Excel软件制作石化环境监测质量控制校准曲线，可节省大量的时间和化学试剂，提高工作效率。这种方法操作简便、快速、直观，并且比以前校准曲线制作数据处理的方法有所创新。     

广东不同质地水稻土Q／I特性与钾肥施用技术的关系的研究

钾素Ｑ／Ｉ特性是表征土壤钾素状况的一个重要指标，它能同时度量土壤钾素的强度和容量．本文研究了广东不同质地水稻土Ｑ／Ｉ特性与大田钾肥施用技术的关系．结果表明：（１）不同质地土壤的Ｑ／１曲线差异明显，砂土类曲线较平缓．粘土类曲线较陡。（２）ＰＢＣｋ与土壤粘粒含量呈极显著正相关（ｒ＝０．６５３）．（３）－△Ｋ０与作物相对百分产量呈极显著正相关（ｒ＝０．８７３），可作为预测当季作物需钾量的参数．（４）ＡＲ＿ｅ￣ｋ与土壤粘粒含量呈显著负相关（ｒ＝－０．５２０），ＡＲ＿ｅ￣ｋ的大小可作为钾肥合理分配的依据．     

Nitrogen accumulation and plant species replacement in three salt marsh systems in the Wadden Sea

Salt marsh development on the coastal barrier island of Schiermonnikoog (The Netherlands) was compared with two other salt marsh systems in the Wadden Sea. Accretion rate, nitrogen accumulation and changes in plant species composition were investigated using chronosequences. The age of the marsh was estimated from aerial photographs and old maps. In 7230 plots, the elevation of the marsh surface, the thickness of the sediment layer (clay) and the presence of plant species was recorded. In addition, the nitrogen pool was measured at each successional stage. Accretion rates were similar in the three salt marshes. Higher accretion rates were found at younger marshes. A strong linear relationship between nitrogen pool size and thickness of the clay layer was found for the three marshes. The accumulation rate of nitrogen is therefore strongly related to the accretion rate. Thus, more nitrogen is present in the sediment of later successional stages where more clay has accumulated. On the high salt marsh (55 cm+MHT),Ameria maritima disappeared andArtemisia maritima, Juncus gerardi andElymus athericus established at sites with a thicker clay layer. On the low salt marsh (25 cm+MHT),Plantago maritima, Puccinellia maritima andLimonium vulgare disappeared andAtriplex (Halimione) portulacoides established. Apparently, with the accumulation of clay and therefore of nitrogen, tall growing species take over in salt marshes not grazed by livestock.     

纳滤处理含Cr(VI)废水的试验研究

采用纳滤对含Cr(Ⅵ)废水进行试验研究,讨论了初始浓度、pH、浓差极化、共存离子对处理效果的影响.试验结果表明,NF90膜对含Cr(Ⅵ)废水有良好的处理效果,去除率超过了98%,出水Cr(Ⅵ)浓度低于0.5 mg/L,可以达标排放或回用于镀件漂洗.     

Improving the extraction of tetrachloroethylene from soil columns using surfactant gradient systems

In this work, we extend the recently developed gradient approach for surfactant-enhanced remediation of dense non-aqueous phase liquid (DNAPL)-impacted sites. The goal of the gradient approach is to maximize the DNAPL solubilization capacity in swollen micelles (Type I aqueous microemulsions) while at the same time minimizing the potential for DNAPL mobilization. In this work, we introduce a modified version of the capillary/trapping curve that we refer to as the gradient curve to help interpret and/or design the gradient approach. The gradient curve presents the residual DNAPL saturation as a function of interfacial tension and microemulsion viscosity. This approach demonstrates that keeping a low viscosity of the microemulsion phase is not only important for keeping a low head loss during surfactant flooding but also to prevent oil mobilization. Eight microemulsion systems were evaluated in this research; these systems were evaluated based on their tetrachloroethylene (PCE) solubilization capacity, interfacial tension (IFT), viscosity, density, and coalescence kinetics. Two of these systems were chosen for evaluation in site-specific column tests using an increasing electrolyte gradient to produce a decreasing IFT/increasing solubilization gradient system. The column studies were conducted with media from Dover Air Force Base in Dover, DE. Both solubilized and mobilized DNAPL were quantified. During the column studies, we observed that substantial PCE was mobilized when the residual level of PCE in the column was significantly higher than the steady-state residual saturation level being approach (as predicted from the gradient curve). Four column studies were performed, three of which were used to asses the validity of the gradient curve in predicting the residual saturation after each gradient step. From these tests we observed that starting IFTs of less than 1 mN/m all produced the same mobilization potential. In the last column, we used an additional gradient step with an initial IFT above 1 mN/m to dramatically reduce the amount of PCE mobilize. Based on the good agreement between column results and projections based on the gradient curve, we propose this as a preferred method for designing gradient surfactant flushing systems.     

阿特拉津降解菌的生长规律及降解特征的实验

应用了从农药厂阿特拉津生产车间污泥中分离出的菌种AT菌，进行了菌种生长曲线的测定，求得AT菌的对数期代时为3．87d，生长速率为0．258d^-1；不同基质浓度的降解实验表明，在农药污染质阿特拉津的低浓度体系中，AT菌降解阿特拉津的反应符合一级动力学模式，属于米氏方程曲线的第一阶段的情形，并拟合出关系式V＝0．064S。     

On the random placement hypothesis

A traditional method of summarizing spatial distribution of species is the observed species-area curve. Often the observed species-area curve is surprisingly close to the expected species-area curve under the hypothesis of random placement of individuals. This has been used as evidence supporting the hypothesis. In this paper, we argue that using the observed species-area curve to test the general random placement hypothesis is highly inefficient. We present a testing method based on the classical ² test for over-dispersion which is not only more efficient but also applicable to situations where complete abundance information are unavailable. We also discuss three alternatives of the hypothesis. The focus of this paper is on these and other general issues relevant to communities of different types. No applications are included in this paper.     

潘谢矿区导水裂隙带发育高度与采厚关系回归分析

根据淮南潘谢矿区最近几年导水裂隙带的实测资料,使用功能强大的数学分析软件Origin对其导水裂隙带与采厚关系进行数学回归分析,并对照现有规范中的关系通式,总结出更适合淮南矿区的预测公式,为以后淮南矿区防水煤柱的留设提供更可靠的理论依据。