工业企业噪声环境影响评价中的布点与预测时段的选择

在工业企业噪声环境影响评价中，由于测点与测量时段选择的不妥，导致测量及预测值“以偏代全”的结果；本文提出了测点合理布设与测量，预测时段科学选择的原则，以使测量与预测结果能较好地符合项目建成前、后噪声环境实际状况。     

中南地区几种土壤的表面电荷特性 Ⅱ.几种测定永久负电荷量的方法的比较

用有效阳离子交换量法、盐滴定-电位滴定法（STPT）、Mehlich法和pfo原理法测定了中南地区几种土壤的永久负电荷量．并与醋酸铵法测定的CEC进行了比较．结果表明：（1）由于醋酸铵法浸提了土壤的部分可变负电荷．它测出的CEC值使其它方法测得的永久负电荷量高．（2）不同方法测得的土壤永久负电荷量差异较大，且用上述四种方法测得的值依次减小．即ECEC＞δP＞CECp＞CECk，这与测定方法和指示离子的本性有关．但都能反映土壤永久负电荷容量的相对大小．（3）不同方法测得的不同的永久负电荷量值．在一定程度上反映着土壤的吸附特性，但有效阳离子交换量法能较好地反映土壤永久负电行量．     

影响高锰酸盐指数测定的主要因素

影响高锰酸盐指数测定准确性的主要因素有样品酸度、蒸馏水水质、高锰酸钾溶液浓度、水浴加热温度和滴定时间。通过环境标准样品的分析试验，考察这5个因素对高锰酸盐指数的影响程度；     

空气微生物研究方法进展与展望

着重论述了空气微生物气溶胶的研究方法，主要有培养基法和非培养基法。培养基法是传统的微生物研究方法，需要花费大量的时间和劳动力，只能够检测活的能够在培养基上生长的微生物，可以大致反映空气中的微生物气溶胶。非培养基法，主要是PCR法，具有敏感性高、快速、特异性强等特点，能够检测出环境样品中绝大多数的微生物，是一种微生物气溶胶检测的有效途径。最后指出实时持续的监测是将来空气微生物研究的努力方向和发展趋势。     

Steady Shallow-Water Current and Solute Transport around a Semi-Conical Headland

Laboratory experiments have been carried out to investigate the effects of a sloping wall headland on the flow characteristics and the associated concentration distributions from a point source around the headland. A semi-conical headland with a slope of 1:2 was set up in a flow basin, 4.8 m long and 3.8 m wide. In this paper, the experimental results of a steady shallow-water current are reported. Three dimensional flow velocities in the basin were measured using Sontek-ADV instrument. The dye concentration levels in the basin were measured by two fluorometers. The experimental results showed a large-scale re-circulation region behind the semi-conical headland. The peak turbulence energy, at about 53% of the local kinetic flow energy, coincides with the region of high velocity gradient. Significant vertical flows were observed around the area near the downhill slope of the headland, with a maximum ratio of vertical to horizontal velocities being about 22%. Such relatively significant vertical scouring velocities, coupled with strong turbulence energy and high horizontal velocity gradients in the same region, could cause severe bed erosion. The experimental results have also been compared with the predicted results of a depth-averaged numerical model. The predicted eddy structure and the concentration distribution in the re-circulation area were found to compare favourably with the experimental results. However, the discrepancies in the flow velocities and the concentration levels near the headland were apparent. It was observed that the dye concentration continued to spread in the cross-stream direction after passing the headland, whereas only a limited extent of the lateral spreading was predicted by the numerical model further downstream of the headland.     

Automatic construction of concept hierarchies: The case of foliage-dwelling spiders

In this paper, we present the hierarchical variable dependencies that were obtained from raw data with the use of two machine learning techniques on an ecological data set. The data set contains features of field margins and the corresponding number of spider species inhabiting them. This data set was used before by domain experts to construct a fuzzy qualitative model with hierarchical variable dependencies, which we use for comparison with our results. One of the machine learning methods constructs a hierarchical structure similar to the one in the experts’ model, while revealing some additional interesting relations of environmental features with respect to the number of spider species. The other method constructs a different hierarchy from the one proposed by the experts, which, according to our classification performance experiments, might be even more appropriate.     

Plant species in arable field margins and road verges of central Norway

Plant species composition and species number were studied in two types of field margins: 31 arable field margins and 33 road verges. Both field margin types were adjacent to intensively managed grass or cereal fields. Effects of eight variables on field margin vegetation were studied. Despite having many plant species in common, composition and species number differed between the two field margin types, due to different ecological conditions and margin management. Arable field margins were composed of tall and/or nutrient demanding ubiquitous species and were characterised by species of later successional stages than those of road verges. The vegetation of road verges was lower and species numbers were higher than in arable field margins. The road verges contained several semi-natural meadow species that are declining in abundance. A CCA ordination of the field margins and the recorded variables showed that plant species composition was significantly affected by thickness of litter, slope, width, moisture level and type of crop in the adjacent field. Number of plant species was significantly higher in mown than unmown margins and generally higher in margins adjacent to fields with mainly grass production than in margins adjacent to fields with mainly cereal crops. In order to preserve botanical diversity in this agricultural landscape, the maintenance of regularly mown road verges should be prioritized.     

快速测定化肥厂氨氮方法的探讨

通过实验验证，认为在化肥厂氨污染环境较重的情况下，改用“市场售纯净水代替无氨水，且用市场售纯净水全程序代替无氨水作参比液的方法进行氮氰测定，此方法具有快速、准确、实用性强的特点获得满意的结果。     

摩擦压力机打击力的测量误差分析

对摩擦压力机打击力测量不准确的现象进行了试验验证 ,并从理论上分析了摩擦压力机打击力测量误差产生的原因 ,探讨了摩擦压力机滑块初速度、工件质量和刚度以及测力传感器质量和刚度对摩擦压力机打击力测量误差的影响。     

利用凝胶层析分离测定胶体态铝和溶解态铝的研究

利用凝胶层析柱分别对高浓度(5.4g·L-1)和低浓度(0.27mg·L-1)的聚合氯化铝溶液和氯化铝溶液进行了层析分离,测定了洗脱流出液的电导率和pH值,并采用Al-Ferron逐时络合比色分析了洗脱流出液中的铝形态分布.结果表明,高浓度和低浓度铝水样中的胶体态铝和溶解态铝浓度均可采用凝胶层析法进行分离测定.利用凝胶层析装置对2.5mL铝水样以1mL·min-1的速度进行洗脱,40～60mL间的洗脱流出液即为胶体态铝,剩余部分为溶解态铝.