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231.
Abstract

This paper reports on research designed to investigate the capacities of different highly characterized peats to remove odorous compounds from liquid swine manure (LSM). Peat types representing a wide range of properties were tested in order to establish which chemical and physical properties might be most indicative of their capacities to remediate odors produced by LSM. Eight percent slurries (of peat/LSM) were measured for odor changes after 24 hours using odor panel and GC/MS‐Solid‐phase microextraction (GC/MS‐SPME) analysis.

The GC/MS‐SPME and odor panel results indicated that, although all peats tested in this study were found to be effective at removing odor‐causing compounds found in LSM, some peats tended to work better than others. Overall, the peats that were the most effective at removing odor‐causing compounds tended to have lower bulk densities, ash contents, fulvic acids contents, and guaiacyl lignins contents,and higher water holding capacities, hydraulic conductivities, “total other lignins”; contents, hydrogen contents, carbon contents, and total cellulose contents.

GC/MS‐SPME analysis was found to be a reasonably inexpensive and efficient way of conducting this type of research. It allows one to identify a large number of the odor‐causing compounds found in LSM, and more importantly, to detect with some precision specific differences in the amounts of these compounds between peat types.  相似文献   
232.
Abstract

An improved Gas Chromatographic method utilizing simple extraction and one‐step purification on solid phase extraction tubes was developed for analysis of trichlorfon as an intact insecticide compound in turfgrass thatch and soil. A Gas Chromatograph/Mass Spectrum (GC/MS) was used for confirmation of trichlorfon structure. The method readily determines trichlorfon in the presence of dichlorvos. Using an electron capture (EC) detector, the detection limits were 0.02 ppm in soil, 0.04 ppm in turfgrass thatch, and 0.09 ppm in soil, and 0.2 ppm in turfgrass thatch using an nitrogen phosphorus (NP) detector.  相似文献   
233.
硅酸盐工业灰渣的基本化学成人是CaO、SiO2,Al2O3等,目前主要用于生产水泥等建筑材料, 西方对工业灰渣CaO-SiO2-Al2O3三元系高钙相平衡过程进行了分析讨论和数学处理。  相似文献   
234.
A new sample preparation technique, solid phase microextraction (SPME), was compared with direct headspace-GC-MS with respect to the type and amount of identified compounds. Three types of LDPE films containing photosensitising additives according to the Scott-Gilead patents and pure LDPE were used as model substances. The polyethylene films were thermally aged at 80‡C after the induction period was surpassed by subjecting the materials to 100 h of UV radiation. The new SPME method was developed using nonpolar poly(dimethylsiloxane) and polar carbowax fibers to extract the low molecular weight products formed in the polyethylene films during aging. Many more products were identified after SPME followed by GC-MS than after direct headspace-GC-MS of the samples. The SPME method allowed the identification of homologous series of carboxylic acids, ketones, and furanones, while direct headspace-GC-MS identified only a few carboxylic acids (C1-C6) and small amounts of some ketones and furanones. In general, SPME was more effective in extracting less volatile products, and in particular, the polar carbowax fiber identified also C7-C12 carboxylic acids and 4-oxopentanoic acid. By SEC and FTIR we confirmed that the number and amount of former degradation products correlated well with the decrease in molecular weights and the amount of formed carbonyl compounds.  相似文献   
235.
固相微萃取-毛细管气相色谱法快速分析水中酚类化合物   总被引:10,自引:4,他引:10  
固相微萃取是一种快速、简便、集萃取浓缩进样于一体的样品前处理技术,具有分析时间短、灵敏度高、无需有机溶剂的优点.本工作用固相微萃取富集水中酚类化合物,毛细管气相色谱分离分析,整个分析过程只需45min,检出限可达1.0~10.0μg/L,已用于地面水、海水、工厂废水中酚类化合物含量的测定.  相似文献   
236.
Surfactant dissolution and mobilization of LNAPL contaminants in aquifers   总被引:1,自引:0,他引:1  
Improper disposal, accidental spills and leaks of non-aqueousphase liquids (NAPL) such as gasoline, fuel oil and creosote result in long-term persistent sources of groundwater pollution.Column and 2-D tanks experiments were conducted to evaluate the use of surfactant-enhanced recovery of light non-aqueous phase liquids (LNAPL) in groundwater aquifers. These experiments focused on the use of surfactants to promote dissolution and mobilization in addition to evaluating the increase of aqueous phase permeability as residual NAPL is recovered. Further experiments are presented that show the innovative use of surfactants during primary pumping to recover free product canpotentially increase the amount of free product recovered, canpotentially reduce the amount of residual NAPL remaining afterprimary pumping and performs better than the use of surfactantsto mobilize trapped residual NAPL.  相似文献   
237.
微生物降解炼油厂含酚废水的实验研究   总被引:3,自引:0,他引:3  
沈齐英  刘录  沈秋英  孔继兰 《四川环境》2003,22(4):23-25,34
采用燕化集团公司炼油事业部污水厂的活性污泥为菌源 ,好氧条件下通过分离、驯化筛选出三种高效降酚微生物。并在实验室模拟三相生物流化床分别对人工含酚废水和燕山石化炼油厂含酚废水进行降解实验 ,结果显示 ,在三相生物流化床中使用微生物包埋法制作的海藻酸钙载体处理含酚废水 ,3小时段内降酚显著 ,t -testP <0 0 1,处理效果良好 ,并以海藻酸钠为主要原料制作载体可以极大降低处理成本  相似文献   
238.
样品前处理是整个样品分析过程中的关键一环,其目的在于减少杂质对待测物的干扰及对目标物进行富集。固相微萃取技术是集采样、萃取、富集、进样于一体的样品前处理新技术。近年来,固相微萃取技术在环境污染物监测分析领域得到了广泛应用,该文章系统地综述了固相微萃取技术在不同环境基质(水体、大气、土壤及沉积物)预处理的方法,比较了不同类型涂层材料(如纳米材料、离子液体等)与装置形式(如内部冷却固相微萃取、箭形固相微萃取等)的优缺点及应用范围。针对现阶段固相微萃取技术应用于不同环境基质中存在的问题和不足,提出进一步研究的方向。  相似文献   
239.
HPLC法测定水和废水中的醛酮类化合物   总被引:3,自引:0,他引:3  
将水样用1mol/L柠檬酸缓冲液调节至酸性(pH=3),其中醛酮类化合物与2,4-二硝基苯肼(DNPH)发生衍生化反应,生成稳定的化合物——腙,经C18固相萃取小柱富集、乙腈淋洗后,用带有二极管阵列检测器的高效液相色谱仪(HPLC)经32 min完成15种醛酮类化合物定性、定量分析。当测定样品为100mL时,检测限均为μg/L级,其中丙酮最高为16μg/L,丁醛最低为1.1μg/L,一般在2μg/L~6μg/L之间。  相似文献   
240.
黄毅  李国傲  杨志鹏  饶竹 《化工环保》2018,38(5):621-626
建立了固相微萃取种类与气相色谱联用测定地下水中12种硝基苯类化合物的分析方法,对萃取头种类、萃取时间、萃取温度、进样口衬管种类等分析条件进行了优化。实验结果表明,该方法的检出限为0.001~0.050 μg/L,线性范围0.005~500 μg/L(相关系数大于0.997),加标回收率为72.1%~122.0%,相对标准偏差为3.65%~12.60%。应用该方法对地下水及地表水样品进行分析,结果表明该方法具有环保、灵敏、快速、简便等特点,适用于水中痕量硝基苯、硝基甲苯类化合物和硝基氯苯类化合物的测定。  相似文献   
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