[HgI4-(R6G)2]n体系的共振散射光谱法测定微量汞(Ⅱ)的研究

在pH值=4.0的条件下,Hg2 ,I-与罗丹明6G(R6G)形成三元离子缔合物.由于HgI4(R6G)2分子间存在较强的分子间作用力和疏水作用力而生成[HgI4-(R6G)2]n纳米微粒.在320 nm处产生一灵敏共振散射(即共振瑞利散射)光谱峰.Hg质量浓度在0.004～0.36 mg·L-1范围内与共振散射光强度呈现出良好线性关系.实验结果表明,本法具有灵敏度较高、选择性较好等特点.用于水样中微量Hg的测定,效果良好.     

新生MnO2对水中活性艳红K-2G的脱色作用研究

以化学法合成的新生MnO2作吸附剂，对水中活性艳红K－2G进行吸附脱色研究，探讨了影响吸附的因素和吸附机理，结果表明：新生MnO2对活性艳红K－2G的吸附符合Langmuir吸附等温式，吸附前溶液pH值是影响染料脱色效果的最主要因素，染料浓度，MnO2投加量和温度影响程度较小，在实验条件下可使活性艳红K－2G的脱色率高达96％。     

基于G1法的应急能力评估指标权重的确定

在对城市应急能力评估前,确定应急能力评估指标的权重是重要问题之一。笔者介绍了一种无需一致性检验的方法G1法;分析并提出城市应急能力评估指标,通过实例利用该方法对指标在体系中的权重进行了计算。结果表明,在指标的数量较多的情形下,其计算量较其他方法明显减少,同时该方法的可操作性强,便于使用。     

中小型燃煤锅炉烟气湿法除尘废水中和处理技术评述

介绍了当前应用于中小型燃煤锅炉湿法除尘废水的各种中和处理技术,提出将除尘废水与中和处理与烟气脱硫结合进行的新工艺,为中小型锅炉烟气湿法脱硫除尘和废水循环回用处理提供了依据。     

新疆G30线速度管理和控制技术研究

速度管理和控制技术是高速公路交通运输中重要的措施和手段,合理的速度管理和控制技术可以提高高速公路的运营管理水平并确保其运营安全.本文针对新疆G30线高速公路的地域、线形、运行特点,探讨了各种速度管理和控制技术在该路段的实施效果,并提出了合理的速度管理和控制措施,以为该高速公路设计和改造升级的速度控制提供借鉴和依据.     

酞菁绿G项目环境风险评价

本文通过对重庆某化工公司酞菁绿G项目物质危险性和生产工艺危险性进行分析,明确了氯气泄漏为该项目存在的最大可信事故,同时利用非正常排放模式分析了氯气在大气中的扩散情况,对氯气泄露导致人员中毒和环境污染进行了环境风险评价,并提出了环境风险防范措施和应急预案。     

Variations in Environmental Tritium Dose Estimates Due to Meteorological Data Averaging and Uncertainties in Pathway Model Parameters

The large amounts of tritium produced at the Savannah River Site (SRS) coupled with the current dose reconstruction study at the facility emphasize the importance of ensuring accurate and efficient prediction of tritium doses to the public. Presently, dose estimates to the general population in the site vicinity are calculated annually using a five year meteorological database. Determining whether detailed monthly dose estimates are necessary or whether annual averaged data is sufficient offers the potential for more efficient dose prediction. In this study, off site collective committed doses and maximum individual doses due to atmospheric tritium releases were calculated according to the methods outlined in the U.S. Nuclear Regulatory Commission's Regulatory Guide 1.109 and compared using monthly versus five-year meteorological data and source terms. Site-specific variables not currently utilized at SRS for annual dose estimates also have been included. In addition, the range of predicted doses, based on the distribution in model parameters given in the literature, were estimated. Finally, a sensitivity analysis was performed in order to determine the influence of model inputs on dose estimates. Results corroborate previous studies by indicating that the primary contributor to infant tritium dose is the ingestion of milk, while for all other age groups, the most important pathway is the ingestion of vegetation. These relative pathway contributions remain constant throughout the year for infants; for children, teenagers, and adults, however, inhalation and absorption of tritium through the skin increases in relative importance in the months of June to September. It was found that the model utilized was most sensitive to dose factors, the ratio of the specific activity of tritium oxide in vegetation to the specific activity of atmospheric tritium oxide, and breathing rates. Most importantly, it was found that over a five-year period, the use of averaged meteorological data results in total individual doses that are only 2 to 6% higher than doses determined monthly, depending on the pathway of interest.     

5G基站电磁辐射环境特征及监测实证研究

根据5G基站工作原理及发射特点,研究了5G基站的电磁辐射方向、强度与用户终端位置分布及应用场景存在的对应关系.经实测验证,终端位置移动将导致电磁辐射方向发生显著变化;多终端窄波辐射相互叠加与应用场景明显相关,基站小区辐射覆盖范围扩大.建议对现行移动通信基站电磁辐射环境监测技术方法进行研究修订.     

过渡金属离子调变对光催化氧化反应的影响

考察过渡金属离子对TiO₂光催化活性的影响,并对过渡金属离子对催化剂TiO₂的光催化调变作用机理进行了初步探讨。结果表明,加入Cu(Ⅱ)可以大大提高TiO₂的光催化活性,反应75 min,可使活性艳蓝X-BR的COD_Cr的去除率达75%以上,对于活性艳红X-3B和活性艳黄X-6G的COD_Cr的去除率达到90%以上。过渡金属离子的调变作用是由于低价的金属离子与H₂O₂作用生成*OH自由基所致。      

Investor demand and spot commodity prices: Reply 2

This, our second reply to Östensson, supplements our earlier more technical analysis with a simple intuitive explanation of how investor demand can be driving commodity prices higher even when investor stocks are falling.