电化学原位产生H2O2的影响因素分析及数学建模

以Pt为阳极,石墨碳棒为阴极,Na2SO4为支持电解质,实验探讨了电化学原位产生H2O2的规律.通过正交试验,确定阴极溶液初始pH值、电流密度CD、通氧流量Q和支持电解质浓度CNa2SO4等主要参数对H2O2产生量的影响,并提出最佳参数组合:pH=2.00,CD=1.02mA·cm-2,Q=0.4L·min-1,CNa2SO4=0.1 mol·L-1,极间距D=6cm.采用二次多项式逐步回归和BP神经元网络2种方法,建立了这些参数对于H2O2产生量的预测模型,并对模型进行检验.结果表明,2种方法在一定参数条件下都可预测阴极区溶液中H2O2浓度,BP神经元网络法预测的准确度好于二次多项式逐步回归方法,且更适合于在线控制.     

JHC－1型COD自动检测仪在污水处理场的应用

选用ＪＨＣ一且型ＣＯＤ自动检测仪对生化进口的ＣＯＤ值连续在线监测，在一年多的运行中检验了仪器的检测精度和准确度，并根据仪器的现场运行情况对仪器进行了一些完善，使之能较好地运行在实际生产中．     

Determination of direct and fugitive PM emissions in a Mediterranean harbour by means of classic and novel tracer methods

Remodelling works are frequent in harbour areas, given that they must adapt to rapidly changing market requirements. Depending on their nature (construction, demolition, etc.), these works may be carried out during long periods of time and thus exert a significant impact on the air quality at the harbours and their surroundings. The air quality at the Valencia harbour was studied during an enlargement project. Four sampling stations aimed to cover the major dust-emitting activities in the harbour. In addition, a sampling campaign was carried out to collect dust materials at their emission sources (e.g., loading and unloading of clinker and petroleum coke, as well as the enlargement works). Differences obtained between PM levels at the monitoring sites were correlated with the distance between sampling stations and enlargement works and/or harbour operations, as well as with the preferential wind direction. In all cases, the days with the highest PM_10 levels were linked to wind directions coinciding with the location of the enlargement works or the clinker and petroleum coke stocks. Classic source apportionment methodologies (PCA and CMB) were applied to the data, but their interpretation was complex due to the similar chemical signatures of PM originating from direct and fugitive emissions from stocked materials (e.g., clinker), and the enlargement works. To overcome this difficulty, a novel non-statistical approach was used to obtain quantitative estimations of the contributions from sources (petroleum coke and clinker), based on the correlation between specific PM components (e.g., carbonaceous species) and source tracers (e.g., V). Finally, a qualitative test using phenolphthalein was devised to identify the presence of clinker on the filters, which provided positive results. This novel tracer approach is thus recommended for harbour authorities.     

南京市污水处理厂污泥处理处置现状

调查了南京市污水处理厂污泥产生量、成分、达标状况以及污泥处置方式,指出了污泥处置中存在的问题。提出依据国家相应的标准和法律法规,建立和完善污泥处理处置产业政策,大力发展相关技术和工艺等建议。     

STORM WATER MANAGEMENT: THE CONCEPT AND ITS APPLICATION1

ABSTRACT: Storm water management is a concept being applied in many urban areas to deal with the increasing problems of storm runoff control and flood damage prevention. This paper introduces the concept and describes the recently completed storm water management program in Columbus, Georgia. Columbus has spent five years and over $200,000 in the development of their problem which includes several basic elements: soils inventory and analysis, hydrologic data collection, sediment and erosion control ordinance, storm water management handbook, urban flood simulation model, interdepartment coordination study, drainage problem categorization study, and a pilot basin study. The results of the pilot basin study are presented including example output from the urban simulation model. The computer output illustrates both the hydrologic-hydraulic and economic capabilities of the model.     

龙江县水环境保护基本思路

介绍了龙江县境内的江河流域、泡沼、泉沟及水利工程概况。提出了对一、二、三类河流的水环境保护,水库的改造与利用,泡沼水域的涵养和利用。并提出了相应的保障措施。     

Acid dissolution methods for heavy metals determination in pine needles

Microwave digestion procedures using HNO₃, HNO₃+H₂O₂, HNO₃+HClO₄, HF mixtures and dry ashing with HF were investigated for heavy metals analysis by either inductively coupled plasma-optical emission spectroscopy (ICP-OES) or ICP-mass spectrometry (ICP-MS) in pine needles. The HF digestion procedures gave about 1.5 times higher values than a mixture of HNO₃+H₂O₂ alone. For Ti determination in needles, the HF procedure using dry ashing is thus recommended. The mean concentrations amounted to 900 mg/kg for Fe and 21.8 mg/kg for Ti in needles collected at an area polluted by a stainless steel works. Those concentrations were 10.6 and 4.3 times higher than in needles collected at an area nearby a pulp mill complex (84.5 mg/kg Fe and 5.0 mg/kg Ti).     

人防工程消防系统设计的若干问题

从人防工程内消防系统的重要性入手,分别从消防水源、消火栓系统的独立分区、消防阀门的设置以及消防排水4个方面探讨了人防工程内消防设计的一些常见问题,强调设计中应考虑平、战结合,方便临战时转换。     

A case study of flood control schemes for the Kakehashi river and their socio-cultural consequences

SUMMARY

This paper is concerned with a twenty-five year campaign against the relocation of the Komatsu-Tenmangu shrine as a result of the enlargement of the Kakehashi river. The Komatsu-Tenmangu shrine is an important cultural property of Japan, and was constructed by Toshitsune Maeda, the third dynasty of the Kaga clan in 1657. It is suggested that the primary reason why it took so long to settle this issue is a flaw in our social system for managing public works. It is concluded that preservation of cultural property is not always contrary to land development, and that the proposed procedures or something like them must be put into practice for the real expansion of our culture.     

非离子表面活性剂淋洗萘污染土壤的修复研究

采用土柱实验研究了非离子表面活性剂对焦化厂萘污染砂土的淋洗效果,同时研究了超声预处理对非离子表面活性剂土壤淋洗的增强效果及粉土和粘土对非离子表面活性剂土壤淋洗的不利影响.研究表明,1)1g·L-1的TritonX-100、AEO-9和Tween80对同一萘浓度(192.4mg·kg-1)的土壤洗脱效率分别为73.0%、81.5%和59.0%,2g·L-1的表面活性剂的洗脱效率要高于1g·L-1的洗脱率,分别为96.5%、95.1%和88.2%.2)对土壤进行短时超声处理(80Hz)促进了洗脱率的提高,超声10min的淋洗效果要高于超声5min的淋洗效果;土壤分别经5min和10min超声处理后,2g·L-1浓度的TritonX-100对萘的洗脱率从94%分别提高到98.8%和99.6%,洗脱时间从255min分别减少到172min和160min.3)砂土中含有粉土和粘土对洗脱效果有不利影响,且粘土的影响要更严重,当萘污染的砂土混入5%的粘土时,2g·L-1浓度的TritonX-100对萘的洗脱率从94.7%下降至73.8%,洗脱时间从255min增加至605min,而混入20%的粉土洗脱率仅下降到88.4%,洗脱时间增加至512min.