Changing effluent chemistry affect survival,growth and physiological function of <Emphasis Type="Italic">Acacia nilotica</Emphasis> seedlings in northwestern region of India

Recycling and conservation efforts for water are the need of the day because of the lack of new water sources and the ever-increasing demand for drinking water. Seedlings of Acacia nilotica L. were irrigated with: canal water (T₁, control); municipal effluent (T₂); textile effluent (T₃); steel effluent (T₄); textile + municipal effluent in 1:1 ratio (T₅); steel + municipal effluent in 1:2 ratio (T₆); steel + textile in 1:2 ratio (T₈) and steel + municipal + textile in 1:2:2 ratio (T₇) with views to observe effluents effect on the seedlings and its adaptability and to recommend safe disposal of these effluents. Seedlings in T₆, T₇ and T₈ showed 50% lesser height and collar diameter than those in control. Seedlings in T₂ attained greatest height, collar diameter, numbers of branches and produced 140 g dry biomass seedling⁻¹. Highest concentration of manganese (Mn), iron (Fe), copper (Cu) and zinc (Zn) and lowest concentration of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) in the seedlings of T₄, T₆, T₇ and T₈ resulted in nutritional imbalance, mineral toxicity and reduction in photosynthetic (Pn) and transpiration (E) rates and caused seedling mortality. Seedlings of T₃ had highest sodium concentration and low concentration of Ca, Mg and micronutrients resulting in nutritional imbalance, augmented chlorosis and reduced gas exchange and biomass by half as compared to control. Increased growth, Pn and E and biomass in seedlings of T₅ over T₃ and survival period in T₆, T₇ and T₈ seedlings suggested a beneficial effect of effluents mixing. Unscientific disposal should be avoided and toxic concentration of metal ions␣may be reduced for long-term application and harmless disposal of effluents in afforestation and urban development.     

重庆气矿污染物排放现状及减排措施分析

重庆气矿在高压、高含硫、高产量条件下的天然气开发过程中,不可避免地会产生废水、废气、废渣、噪声等污染物,并对环境造成影响。为此,重庆气矿对污染物排放的种类、特点及现有治理措施和效果进行了分析,并对存在的问题提出了具体的防治措施。     

Determination of 10 particle-associated multiclass polar and semi-polar pesticides from small streams using accelerated solvent extraction

A new analytical method using accelerated solvent extraction was developed for the determination of 10 particle-associated polar and semipolar pesticides. In addition, six deuterated analogues of the target compounds were evaluated as internal standards. The method yielded acceptable accuracy (73–103% recovery) and precision (<25% relative standard deviation) for eight compounds. Using size exclusion chromatography (SEC) as cleanup step resulted in higher recoveries compared to solid phase extraction (SPE) cleanup.

Deuterated standards with 10 or more deuterium atoms performed well as internal standards concerning similar recovery and correlation with the target analytes.

The method was employed to extract particle-associated pesticides from 16 streams located in an area with intense agriculture in France. Acetochlor, pirimicarb, tebuconazole, fenpropidin, -endosulfan and chlorfenvinphos were detected at concentrations up to 1 mg kg⁻¹ dry weight. A comparison with aquatic toxicity data indicated potential risk to the benthic fauna exposed to these concentrations of pirimicarb, -endosulfan and chlorfenvinphos.

We suggest that the method presented here be used for the extraction and quantitation of particle-associated polar pesticides.     

细水雾中雾滴和高温环境的热质交换研究

由雾滴的表面的组分方程和能量方程入手,探讨雾滴在静止的高温环境中的热质交换及生存时间。应用折算薄膜理论,通过特征时间的比较,提出雾滴与高温环境主要通过沸腾机制实现热质交换;考虑滴径与速度变化的耦合作用,应用数值方法研究雾滴在强迫对流环境中与高温环境的热质交换情况。结果表明:对于滴径较小的雾滴不可能达到火焰区或可燃物表面实施火焰冷却和表面冷却,其灭火作用主要依赖于汽化吸热。     

Characterization of Organic Compounds in Compost-Amended Soil

Samples of compost-amended soil from waste dumping sites in Lagos Metropolis were extracted with dichloromethane (3 × 20 cm³) and the extract was evaporated at 35 °>C. The residue was extracted with 2,2,4-trimethylpentane, and portions of the solution were applied to a column containing silica gel from which aliphatic and aromatic hydrocarbons were eluted with n-hexane and toluene respectively. Analysis of the n-hexane fraction using gas chromatography showed the presence of a mixture of aliphatic hydrocarbons, ranging from C₉ to C₂₅, while ultraviolet analysis of the toluene fraction suggested 1,2-benzanthracene; 2,3-benzphenanthrene, chrysene and pyrene as polyaromatic compounds present in samples analyzed. The crude extracts were highly coloured and viscous. Total extractable organic residues in the 2,2,4-trimethylpentane extracts ranged from 36 to 89 mg g^-1 of soil.     

气相色谱法测定废水和废气中N′,N-二甲基甲酰胺

以气相色谱石英毛细管柱分离、ＦＩＤ检测,测定废水和废气中Ｎ′,Ｎ－二甲基甲酰胺（ＤＭＦ）。在１０ｍｇ／Ｌ～１８８１０ｍｇ／Ｌ范围内有良好的线性关系。检测限：废水为０５ｍｇ／Ｌ;废气为０８ｍｇ／ｍ３。样品测定的相对标准差为４％～８％,回收率在７６％～１１２％之间,精密度和准确度均较好     

原子荧光光谱法同时测定环境水体中痕量锡和锌

采用原子荧光光谱法同时测定环境水样中痕量锡和锌,优化了试验条件。锡在1.00μg/L～10.0μg/L、锌在20.0μg/L～200μg/L范围内线性良好,方法检出限锡为0.13μg/L,锌为1.76μg/L,锡和锌标准溶液测定的相对标准偏差分别为2.9%和4.0%,环境水样加标回收率锡为96.4%～106%,锌为92.0%～111%。     

杭州市大气PM2.5和PM10污染特征及来源解析

2006年在杭州市两个环境受体点位采集不同季节大气中PM_2.5和PM₁₀样品,同时采集了多种颗粒物源类样品,分析了其质量浓度和多种化学成分,包括21种无机元素、5种无机水溶性离子以及有机碳和元素碳等,并据此构建了杭州市PM_2.5和PM₁₀的源与受体化学成分谱;用化学质量平衡(CMB)受体模型解析其来源。结果表明,杭州市PM_2.5和PM₁₀污染较严重,其年均浓度分别为77.5μg/m³和111.0μg/m³;各主要源类对PM_2.5的贡献率依次为机动车尾气尘21.6%、硫酸盐18.8%、煤烟尘16.7%、燃油尘10.2%、硝酸盐9.9%、土壤尘8.2%、建筑水泥尘4.0%、海盐粒子1.5%。各主要源类对PM₁₀贡献率依次为土壤尘17.0%、机动车尾气尘16.9%、硫酸盐14.3%、煤烟尘13.9%、硝酸盐粒8.2%、建筑水泥尘8.0%、燃油尘5.5%、海盐粒子3.4%、冶金尘3.2%。     

顶空固相微萃取-色谱质谱联用测定饮用水中二甲基异冰片和土味素

研究了顶空固相微萃取-气相色谱质谱联用测定饮用水中二甲基异冰片和土味素的方法。结果表明,当选用聚二甲基硅氧烷(PDMS)萃取纤维萃取头,萃取温度为60℃,萃取时间为40min时,得到二甲基异冰片标准曲线方程为y=122.59+157.76x,相关系数(R)0.9998;土味素的标准曲线方程为y=14.847+180.99x,相关系数(R)0.9999;检出限为0.1ng/L,相对标准偏差在0.99%～4.05%之间,加标回收率86.4%～109.5%。     

离子色谱法测定丙烯酸丁酯生产废水中丙烯酸和对甲基苯磺酸

建立了用离子色谱法测定丙烯酸丁酯生产废水中丙烯酸和对甲基苯磺酸的新方法。采用IonPac AS11-HC阴离子色谱柱,淋洗液为30mmol/L的NaOH淋洗液,流速1ml/min,抑制电流75mA。丙烯酸根的检测下限为0.44mg/L(峰面积)、0.46mg/L(峰高),保留时间、峰高、峰面积的变异系数分别为0.03%、0.50%、0.50%,峰高、峰面积的线性回归系数R分别为0.9929、0.9954。对甲基苯磺酸根的检测下限为0.49mg/L(峰面积)、0.48mg/L(峰高),保留时间、峰高、峰面积的变异系数分别为0.02%、0.48%、0.47%,峰高、峰面积的线性回归系数R分别为0.9990、0.9998。常规无机阴离子对丙烯酸、对甲基苯磺酸的测定没有干扰。对实际废水样品进行分析,丙烯酸、对甲基苯磺酸的回收率分别为101.6%～104.4%、95.4%～96.8%。方法简便、灵敏、可靠。