A model for prediction of product distributions for the reactions of phenol derivatives with hydroxyl radicals

In this study, with the intention of estimating the photocatalytic or photodegradation rates and finding certain predictors to be used for the determination of the most probable reaction path and the primary intermediate, the reactions of (*)OH radicals with 11 phenol derivatives including benzene were modeled. For 43 possible reaction routes, calculations of the geometric parameters, the electronic and thermodynamic properties of the reactants, the product radicals and the transition state complexes were performed with the semiempirical PM3 and DFT/B3LYP/6-31G(*) methods. The solvation effects were computed using COSMO as the solvation model. Based on the results of quantum mechanical calculations, the rate constants, the branching ratios and the product distributions of all the possible reaction paths were calculated by means of the transition state theory. Three predictors were determined for the prediction of the most probable transition state and the reaction path. The differences in the reaction rates were explained in terms of the presence of hydrogen bonds in the transition state complexes and the entropy effects. Finally the results obtained were compared with the available experimental data in order to assess the reliability of the proposed model.     

含铬污液在土壤中迁移规律的研究

通过静态吸附和动态土柱淋溶实验,研究了含铬污液中Ｃｒ（Ⅲ）、Ｃｒ（Ⅵ）在土壤中的迁移规律。结果表明,土壤对Ｃｒ（Ⅲ）、Ｃｒ（Ⅵ）的等温吸附过程均符合Ｌａｎｇｍｕｉｒ方程,土壤对Ｃｒ（Ⅲ）、Ｃｒ（Ⅵ）的饱和吸附量分别为２．１７＊１０＾４ｍｇ／ｋｇ、１７５ｍｇ／ｋｇ;动态截留量分别为７．００＊１０＾３ｍｇ／ｋｇ、５６．７ｍｇ／ｋｇ。     

Metal availability and uptake by sorghum plants grown in soils amended with sludge from different treatments

Several factors depending on the sludge, the soil, or the combination of both substrates, may affect element availability to plants. In this study, an assessment was done of the effect of two sludges obtained by different processes (activated sludge and facultative stabilization pond) on heavy-metal availability and uptake by sorghum plants in soils with high and low copper contents. Results obtained for DTPA-extractable metal indicated higher metal availability in sludge-amended soils. In addition, sludges caused changes in copper and zinc distribution in soil, indicating in most cases a discrete increase in the more labile metal forms. However, observed changes did not increase heavy metal concentration in plant leaves, indicating that assessment of metal availability by a chemical procedure (single extraction or metal fractionation) would not permit a good prediction of metal bioavailability. On the other hand, sludge application at a rate of 100 t ha⁻¹ to high-copper agricultural soils would not imply greater mobility of this metal on account of a greater sorbing capacity provided by the sludges. Such results would indicate that sludges from wastewater treatment plants, meeting the standards of heavy metal contents, regardless of the process by which they were obtained, may be applied to several kinds of soil, even to high-copper soils, with no risk of increasing heavy metal bioavailability to phytotoxic levels in the short range.     

The role of the organisational psychologist in disasters and emergency situations

Interventions in extreme situations, such as natural or technological disasters, terrorist attacks or emergencies in general, take place in settings of great uncertainty and are always accompanied by extraordinary circumstances. For this reason, there are various processes related to implementing intervention protocols that must be carefully examined, including an evaluation of work scenarios, personnel selection, within-group relationships in work teams, decision-making processes, or certain peculiarities of burnout among emergency personnel. In the view of this author, an ad hoc review of the role of the organisational psychologist can highlight interesting analysis and performance possibilities that could make work in emergency and disasters contexts more effective. The aim of this paper is to provide an overview of the role of the organisational psychologist pre-and post-disaster. Furthermore, it supports the idea that professional profiles must be designed that take into account specific knowledge and skills, as well as certain aptitudes and values.     

基于环境外部经济性的环境治理手段——以滇池白鱼河河口湿地地块的模拟案例为例

为了解决湿地建设投资渠道的问题,提出了利用环境外部经济性来改善和保护环境的发展思路。其重点是将湿地从普通概念上的公共产品转化为一段时限内的经营性项目,利用某种经营项目所产生的对环境的外部经济性来改善环境。为了验证上述思路的可行性,结合滇池湿地现状,利用湿地的自然景观价值,通过企业对这种生态景观环境的资源化利用过程,即湿地景观建设和管养,增强对污染水体的治理等角度进行了实际模拟实验。     

Modeling inorganic aerosols and their response to changes in precursor concentration in Mexico City

Based on data from the 1997 Investigación sobre Materia Particulada y Deterioro Atmosférico-Aerosol and Visibility Evaluation Research (IMADA-EVER) campaign and the inorganic aerosol model ISORROPIA, the response of inorganic aerosols to changes in precursor concentrations was calculated. The aerosol behavior is dominated by the abundance of ammonia and thus, changes in ammonia concentration are expected to have a small effect on particle concentrations. Changes in sulfate and nitrate are expected to lead to proportional reductions in inorganic fine particulate matter (PM2.5). Comparing the predictions of ISORROPIA with the observations, the lowest bias and error are achieved when the aerosols are assumed to be in the efflorescence branch. Including crustal species reduces the bias and error for nitrate but does not improve overall model performance. The estimated response of inorganic PM2.5 to changes in precursor concentrations is affected by the inclusion of crustal species in some cases, although average responses are comparable with and without crustal species. Observed concentrations of particle chloride suggest that gas phase concentrations of hydrogen chloride may not be negligible, and future measurement campaigns should include observations to test this hypothesis. Our ability to model aerosol behavior in Mexico City and, thus, design control strategies, is constrained primarily by a lack of observations of gas phase precursors. Future campaigns should focus in particular on better understanding the temporal and spatial distribution of ammonia concentrations. In addition, gas phase observations of nitric acid are needed, and a measure of particle water content will allow stable versus metastable aerosol behavior to be distinguished.     

Western Mediterranean immature loggerhead turtles: habitat use in spring and summer assessed through satellite tracking and aerial surveys

An aerial survey was conducted in early spring 2002 over the continental shelf of the Balearic Archipelago to study the distribution of neritic loggerhead turtles. Furthermore, five juvenile loggerhead turtles [straight carapace length (SCL) range 37.1–48.7 cm], were instrumented with transmitters and monitored during 2003 by satellite tracking to study habitat use over a broader geographical range. The distribution of the turtles over the continental shelf matched habitat availability, as defined by depth. However, those tracked by satellite spent most of the time in the oceanic waters of the Algerian basin and generally avoided continental shelf areas. In these turtles, average speed of travel and mean cosine of turning angle did not significantly differ between habitats, indicating that avoidance of shelf areas is not due to active habitat selection. On average, tracked turtles spent 35.1±19.7% of the time at the surface, although surface time was much greater in the turtle with the shortest carapace length, suggesting that this individual had limited swimming capacity. We conclude that the transition between passive drifting and active habitat selection occurs at an SCL of about 40 cm. The turtles followed tracks that matched prevailing currents, but on some occasions they also swam upstream. Hence, the distribution of late juvenile loggerhead turtles in the southern and central western Mediterranean may reflect a combination of passive drifting and active habitat selection.Communicated by O. Kinne, Oldendorf/Luhe     

仰望建筑--凝固的音乐

建筑,一首凝固的音乐。一首用所有的石头和建材筑成的,如雕塑般,如诗歌般,既静态又动感的音乐。好的艺术是不由得亵渎的,更需要读懂它性灵的人。好的建筑更是我们是需要仰望的,那些思想的碎片、艺术的精华、生活的智慧,藏在片瓦只木中,因为无语,故由人评说。建筑,代表着一个时代,又跨越着每个时代。它用一个时代的语言和思想来诠释,却在另一个时代又得到重新诠释和解读。每一个时代的评说各有千秋,建筑又自成一格,但千百年过去了,若干个时代变迁了,民族的建筑,却总有一种传承的核心及同质的文化。尤如一首首凝固的音乐史诗,尽管历尽桑田,却…     

"绿色地产"概念之虞

全面节能,务必节能!当土地、水、电、油等资源一再告急时,作为人均土地资源占有最少的国家,强调节能已成为国计民生的重中之重.根据有关部门的测算,我国目前住宅总能耗已占全国能耗的37%,98%的住宅为高耗能建筑,新建住宅仅有5%符合节能标准.我国的单位建筑面积采暖能耗是同等条件下发达国家建筑能耗的3倍.夏季城市电能消耗的40%都用到了空调上.非常明显,我国的房地产业是真正的“耗能大户”     

大连市环境污染经济损失估算

在大量的社会调查的基础上，采用市场价值法、人力资本法、恢复费用法、机会成本法和调查评价法，分别估算了大连市大气污染、水污染、噪声污染和固体废物污染造成的损失费用。估算结果表明：大连市1996年环境污染损失为12．53亿元，约占当年GDP的1．71％。