Estimation of Efficiency of Processing Soil Samples for Pesticide Residues Analysis

The efficiency of four sample processing methods was tested with eight different types of soils representing the major proportion of cultivated soils. The principle of sampling constant was applied for characterizing the efficiency of the procedures and testing the well-mixed status of the prepared soil. The test material was 14C-labeled atrazine that enabled keeping the random error of analyses ≤ about 1%. Adding water to the soil proved to be the most efficient and generally applicable procedure resulting in about 6% relative sample processing uncertainty for 20 g test portions. The expected error is inversely proportional to the mass of test portion. Smashing and manual mixing of soil resulted in about four times higher uncertainty than mixing with water. Grinding of soil is applicable for dry soils only, but the test procedure applied was not suitable for estimating a typical uncertainty of processing dry soil samples. Adding dry ice did not improve the efficiency of sample processing.     

Analysis of a laser process for permanently degrading a photo-activated adhesive joint

A pulsed, laser process has been developed to reduce the permanent strength of photo-activated adhesive joints prior to work-piece de-bonding. The objective of this investigation was to gain insight into the relationships between carbon black content of the adhesive, laser delivery mode, heat transfer, and adhesive degradation. To do so, a variety of experiments were performed to characterize process sensitivity, radiation absorption within the adhesive joint, and thermal decomposition of the adhesive. In addition, heat transfer analysis was conducted to predict adhesive temperatures during the process.The results of this investigation indicate that the strength diminishment of an adhesive joint occurs after it has absorbed a train of high power pulses in rapid succession. The vast majority of strength diminishment occurs over a very narrow time window and is highly correlated to the rapid emission of gray smoke/vapor from the adhesive joint. For this to occur, the adhesive must contain carbon black. It is also highly correlated to a rapid increase in temperatures throughout the adhesive matrix. Laser pulse parameters that do not lead to this rapid increase, will not initiate adhesive degradation.The inclusion of carbon black into the adhesive promotes heat absorption and increased temperatures in the adhesive joint. These temperatures are large enough to enable adhesive decomposition. But the time span over which this happens is too small for significant damage to occur. It is currently hypothesized that high temperatures local to the carbon black particles may be the source of adhesive degradation.     

Effect of cooling rate and laser process parameters on additive manufactured Fe–Ti–C metal matrix composites microstructure and carbide morphology

In this paper, laser additive manufacturing (LAM) of Fe–TiC composite coating on AISI 1030 carbon steel is investigated using a numerical and experimental method. In order to have a desired result using LAM, it is crucial to understand the effects of the process parameters’ values on the TiC morphology and microstructure. For this purpose, the LAM process is numerically simulated in order to calculate cooling rate and peak temperature. Experimental data and numerical results are in good agreement in terms of the phase development. Results show that cooling rate plays a crucial role in phase transformation in the clad, however, final microstructure strongly depends on the cooling rate and powder's chemical composition. Two main carbide morphologies (i.e. dendritic and particulate) are studied and relevant cooling rates are detected. Based on this paper and developed map, it is possible to control the cooling rate in order to achieve specific carbide morphologies in the clad. In this study, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) are used to characterize clads’ microstructure.     

油田含油污水处理方法对比研究

石油因应用广泛,其开采量不断加大,而石油在开采过程中会产生大量的含油废水,油田采出水其水量大、水质成分复杂,若不有效处理,将对周围造成不利影响。通过论述油田含油污水的来源、分类、常用处理方法,并从三级处理、四个油形、COD去除效率三方面进行分析,最终得出富含浮油污水优选重力分离法进行处理;富含分散油污水优选浮选法、过滤法进行处理;富含乳化油污水优选膜分离法进行处理;富含溶解油污水优选活性污泥法进行处理。     

本底大气CO2观测分析过程中QA/QC方法的建立与评估

建立科学规范的本底大气CO2采样观测分析过程中的质量保证与质量控制方法,是实现该数据资源同化和共享的基础.本研究以中国气象局温室气体网络化采样观测经验为基础,以便携式采样观测、波长扫描-光腔衰荡(WS-CRDS)分析技术为例,系统介绍了我国青海瓦里关全球本底站大气中CO2采样观测过程中的质量保证措施,样品分析过程中的玻璃瓶质量保证措施和样品分析过程中的系统质量控制方法、数据处理过程中的校正方法、数据分级质量标记和数据拟合插补方法等;并重点对该方法中几个关键步骤进行了评估验证;最后,应用本研究方法,对我国3个区域大气本底站CO2的采样观测数据进行了处理和浓度变化特征分析,说明本研究方法也可以较好地捕捉区域和局地环境因素影响对观测结果的影响,并客观、准确地反映该区域的自然和人为活动特征.     

黑龙江省大豆加工业污染调研及分析

黑龙江省是中国的大豆之乡，在中国大豆生产中起着举足轻重的作用。近年来，大豆加工业迅猛发展，但与此同时产生的废水处理问题也不容忽视。本文通过实地调研和现状分析，指出目前大豆加工企业废水处理共有问题，并提出相应的对策和措施，为中国大豆加工业污水处理提供基础和借鉴。     

PRIMARY AND SECONDARY IMPACTS OF A WATER RESOURCE DEVELOPMENT PROJECT1

ABSTRACT: At a time in history when water resource development in the United States is being condemned as both economically inefficient and an environmental disaster, perhaps economists need to look back at previous development to see what the fruits of water development (be they sweet or sour) have been. The Boise Project of south-western Idaho is 70 years old and to some people it represents a gross error in resource use, while to others it represents a means of livelihood and well being. A recent research project at the University of Idaho attempted to measure not only the direct economic income benefits of the project (from irrigation), but also the indirect or secondary income benefits (from the food processing industry). Periodic regional input-output tables were constructed to assess the income generated from irrigation and food processing over the period from 1946 to 1970. Input-output analysis allowed researchers to evaluate the direct and indirect impacts of both the irrigation sector and the food processing sector and to compare their growth over time.     

专用铁路开采沉陷信息综合处理系统

依据现行铁路规程、规范 ,以随机介质理论、概率积分法、条件模拟、系统工程方法等为基础 ,应用数据仓库原理、专家系统理论、CAD技术、人机交互技术以及系统集成技术 ,针对专用铁路开采沉陷与治理的特点 ,开发了矿区专用铁路开采沉陷信息综合处理系统 ;实现了实测数据分析与处理、信息预测预报、模型计算、图件绘制、报表与曲线输出、措施知识库管理等的系统化和自动化。笔者介绍了该软件系统的总体目标、系统设计、关键技术及系统构成和主要功能。     

模糊信息优化处理方法在陕西泾阳南塬塬边斜坡稳定性区划中的应用

结合野外调查,应用模糊信息优化处理方法对泾阳南塬塬边斜坡各评价单元进行了评价,最后根据评价结果将塬边斜坡进行了稳定性区划.