35Cr2Ni4MoA 材料防腐蚀性能验证研究

目的验证35Cr2Ni4MoA材料采取镀硬铬、封孔表面防护的耐腐蚀性能。方法开展35Cr2Ni4MoA材料表面镀硬铬有无封孔防护状态下的实验室加速腐蚀环境试验,研究材料表面腐蚀行为特点,加速腐蚀试验共8个周期。通过蚀坑深度、腐蚀面积、单位面积腐蚀数量等描述35Cr2Ni4MoA材料表面腐蚀情况。结果 35Cr2Ni4MoA材料表面镀硬铬和封孔防护后试验件腐蚀程度明显减低。结论镀硬铬、封孔表面防护能有效提高海洋环境下35Cr2Ni4MoA材料表面的耐蚀性能。     

A Fine-Scale <Emphasis Type="Italic">k</Emphasis>−ε Model for Atmospheric Flow over Heterogeneous Landscapes

A multi-purpose model for small-scale atmospheric flows over heterogeneous landscapes is being developed. The aim of this research is to build a tool able to predict the dynamical (wind, turbulence) and diffusive (gases, particles) fields over landscapes characterised by heterogeneous plant cover. In its present stage of development the model is based on the numerical integration of neutral atmospheric flow equations, using an energy-dissipation closure scheme and over a domain that may include vegetation layers. Three validation cases of the model are presented: (i) response of the airflow to a change in surface roughness; (ii) airflow within and above a horizontally homogeneous plant canopy; (iii) airflow over two complex forest-to-clearing and clearing-to-forest transitions. All simulations provide results in good agreement with the experimental data, except for turbulent kinetic energy just after a clearing-to-forest transition. This result is not surprising for a statistical k– model in a flow region characterised by strong distorsion and intermittent turbulence. However the overall good performance of the model is promising for environmental research at fine scales over heterogeneous landscapes.     

人工湿地中蛭石填料净化污水中氨氮能力

研究了蛭石吸附污水中氨氮的吸附容量以及蛭石去除氨氮的等温吸附曲线，探讨了水中pH、温度、浓度对氨氮去除量的影响以及饱和蛭石再生后的效果，结果表明，蛭石的饱和和吸附量为20．83mg／g；蛭石吸附量在pH2．0～6．0范围内随着pH的增大而增大，最佳pH为4．0～6．0；温度在15℃～35℃范围内，吸附量随温度的升高减小；氨氮的去除率随着蛭石用量的增加而增加。这为蛭石作为一种新型填料提供了基础数据和理论依据。     

单甲脒在大鼠体内的吸收,代谢和排出的研究

大鼠经口灌喂单甲脒后，通过测定实验动物不同时间的血、尿及内脏中单甲脒和代谢产物２，４－二甲基苯胺的含量，研究了单甲脒在大鼠体内的呼收、代谢和排出的变化规律。单甲脒经消化道被迅速吸收，４８ｈ内９０％在肝脏代谢转化。７２ｈ内９０％以代谢产物的形式随尿液排出体外。     

氯与高锰酸钾复合药剂对水中苯酚及氯酚的去除效果

以水中的苯酚、4－氯酚和2，4－二氯酚为研究对象，研究氯与高锰酸钾复合药剂对酚类物质的去除效果，通过紫外吸收光谱扫描分析，结果表明，氯与酚类物质的作用不能降低酚类物质对水的污染程度，且可能引起二次污染，而高锰酸钾复合药剂的作用能使酚在紫外区的特征吸收峰值有很大降低，表明高锰酸钾复合药剂对酚类物质具有很好的去除效果。     

单甲脒和2,4—二甲基苯胺在大鼠肝脏中的残留分析

本文研究了大鼠肝脏中单甲脒及其代谢产物２，４－二甲基苯胺残留量的气相色谱分析方法。肝脏匀浆用１ｍｏｌ．１＾－１ｈＨＣ１加热回流提取，等分为Ａ，Ｂ两份，Ａ份溶液调ｐＨ至１３后用石油醚萃取定容；Ｂ份加两倍体积的１０ｍｏｌ．１＾－１ＮａＯＨ溶解后用石油醚萃取定容。分别经七氟丁酸酐衍生化，用带电子捕获检测器的气相色谱仪测定２，４－二甲基苯胺的含量，最后计算单甲脒的残留量。该方法对２，４－二甲基苯胺的最低检     

Aktuelle und künftige Emissionen treibhauswirksamer fluorierter Verbindungen in Deutschland

Zusammenfassung  Die fluorierten Verbindungen Schwefelhexafluorid (SF₆), perfluorierte Fluorkohlenwasserstoffe (CF₄, C₂F₆) und wasserstoffhaltige Fluorkohlenwasserstoffe (H-FKW) z?hlen zu den atmosph?rischen Spurengasen mit extrem hohen Treibhauspotentialen. Untersucht werden für Deutschland ihre realen Emissionen für 1990–1995, und Prognosen für die Jahre bis 2020 werden aufgestellt. Diesen Prognosen zufolge vermindern sich die j?hrlichen Freisetzungen von CF₄/C₂F₆ von 1990 bis 2000 von 335 t/34 t auf 100 t/10 t infolge Automatisierungsma?nahmen an der Hauptquelle (Aluminiumhütten). Die Emissionen von SF₆ bleiben dagegen bis 2020 im Schwankungsbereich zwischen 200 und 300 t j?hrlich. Hauptemittenten sind nicht elektrische Schaltanlagen, da diese relativ dicht sind und über ein Entsorgungs-und Wiederaufarbeitungskonzept für gebrauchtes Gas verfügen, sondern mit gro?em Abstand Autoreifen und Schallschutzscheiben. Bei den erst seit 1990 gezielt als FCKW-Nachfolger eingesetzten H-FKW ist mit fortschreitender FCKW-Substitution in der station?ren und mobilen K?lte-und Klimatechnik, bei PU-Montageschaum und Asthmasprays mit einer sprunghaften Zunahme der Emissionen bis auf über 9700 t/a ab dem Jahr 2007 zu rechnen, sofern sich nicht halogenfreie Alternativen st?rker durchsetzen. Im Jahr 2020 werden bei Annahme dieser Trends die kumulierten Emissionen der genannten fluorierten Verbindungen der Treibhauswirkung von 25 Mio. t CO₂ entsprechen (GWP-Betrachtungszeitraum: 100 Jahre).      

2,4-二氯苯酚溶液的挥发性及其处理对策

研究了温度、pH、曝气等因素对2，4-二氯苯酚溶液挥发性的影响。结果表明，高温、低pH及高曝气量可提高2，4-二氯苯酚的挥发程度。研究表明，直接电解法处理此类废水效率较低，针对此情况提出了应注意的事项及基本处理对策。     

The effect of 4-Nonylphenol on the pigmentation of<Emphasis Type="Italic">Ocimum basilicum</Emphasis> (Basil)

BACKGROUND, AIM AND SCOPE: Tests during the last few years have confirmed that 4-nonylphenol (4-NP) can have oestrogen-like effects (xeno-hormone) on animal organisms. The objective was to firstly evaluate the ecotoxicological effects of 4-NP on plants such as hydrocultures. To clarify how this substance interferes with the photosynthetic system of plants, various tests were carried out using the basil plant (Ocimum basilicum). METHODS: The effect of the pollutant 4-NP on the pigment content in the leaves of the basil plant was analysed with the use of High-Performance-Liquid-Chromatography (HPLC). RESULTS AND DISCUSSION: A general assessment of the HPLC data revealed that plants that came in contact with the 4-nonylphenol showed a change in pigmentation. More chlorophyll a and b was produced, although at the same time a higher production of degradation products and by-products of the chlorophylls was observed. These occurrences can therefore be seen as an impairment of the photosynthetic process. The contaminated plants produced less xanthophylls than the non-contaminated ones, though these differences were statistically not significant. CONCLUSION AND PERSPECTIVE: The variations on the pigment content in the leaves of the basil plant can be interpreted as a consequence of the 4-NP application. It was, however, not investigated whether the plants absorbed the pollutants directly. The effect could have been caused by adsorption of the oily substance to the roots, and this could have led to a hindrance of the uptake of nutrients and possibly water. In order to clarify this further, biochemical experiments are being conducted.     

Xenobiotics: Substrates and inhibitors of the plant cytochrome P450

The ability of a plant cytochrome P450 to bind and metabolise plant endogenous molecules and xenobiotics was investigated. The work was performed on the yeast-expressed CYP73A1, a cinnamate 4-hydroxylase isolated fromHelianthus tuberosus. CYP73 controls the general phenylpropanoid pathway and is likely to be one of the most abundant sources of P450 in the biosphere. The enzyme shows a high selectivity toward plant secondary metabolites. Nevertheless, it oxygenates several small and planar xenobiotics with low efficiency, including an herbicide (chlorotoluron). One xenobiotic molecule, 2naphthoic acid, is hydroxylated with an efficiency comparable to that of the physiological substrate. This reaction was used to devise a fluorimetric test for the rapid measurement of enzyme activity. A series of herbicidal molecules (hydroxybenzonitriles) are shown to bind the active site without being metabolised. These molecules behave as strong competitive inhibitors of CYP73 with a K_i in the same micromolar range as the K_m for the physiological substrate. It is proposed that their inhibition of the phenylpropanoid pathway reinforces their other phytotoxic effects at the level of the chloroplasts. All our results indicate a strong reciprocal interaction between plant P450s and xenobiotics.