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991.
The decomposition of chloroform (CHCl3) diluted in air was studied. The experiment was carried out by using a gliding arc plasma. Different values of initial concentrations of chloroform, total gas flow rates, and input power frequencies have been used to investigate this effects on the conversion reaction products both qualitatively and quantitatively. Experimental results indicate that the maximum conversion of chloroform was 97% at a total gas flow rate of 180?L?h?1 containing 1% chloroform. Using air as carrier gas, decomposition of CHCl3 produces CCl4, CO2, CO, and Cl2 as the main products. Small amounts of HCl and COCl2 are also detected. Liquid products were also produced. 相似文献
992.
On the utilization of agricultural by-product, charcoal from rice bran was produced. The adsorption characteristics of indigo carmine onto charcoals from rice bran were investigated by the batch method. The yield and surface area of charcoal were decreased and increased with increase of carbonization temperature, respectively. The removal ratio of indigo carmine was high with the charcoal carbonized at higher temperature. In the relationship between the amount of indigo carmine adsorbed and the square root of elapsed time, a good linearity was recognized. The kinetic constant of adsorption removal for indigo carmine was rapid in the charcoal carbonized at higher temperature. The adsorption characteristics for indigo carmine removal by charcoal from rice bran were dominated by the value of their surface area. 相似文献
993.
994.
Three endocrine disrupting chemicals (EDCs), triclosan (TCS), 4-n-nonylphenol (4-n-NP), and di-n-butyl phthalate (DBP) were determined using stir bar sorptive extraction (SBSE) along with high-performance liquid chromatography/photodiode array detection (HPLC/DAD). Benzyl butyl phthalate was used as an internal standard. The targeted analytes could be rapidly determined with limits of quantification (LOQ) ranging from 4.1 (DBP), 10 (TCS), to 34 (4-n-NP)?µg?L?1 in real samples such as bottled waters, personal care products, soaps, lotions, and urine. The results show that the developed analytical scheme is solvent-saving, efficient, and capable of fast screening samples for these common EDCs. 相似文献
995.
Adnan M. Massadeh Wail A. Hayajneh Abdullah Shorman Mohammad Y. Gharaibeh Moh'd Mohanad A. Al-Dabet 《毒物与环境化学》2013,95(7):1244-1255
A total of 200 Jordanian children were classified into two groups: 100 Fe replete and 100 Fe deficient with ages ranging between 3.0 and 12.0 years (6.9 ± 2.7 years). All participants were chosen according to proper selection criteria followed by the sample collection: the samples were analyzed for hemoglobin and red blood cells; ferritin, an immunoassays-based instrument; and levels of Pb, Cu, and Zn. There were no significant differences between genders regarding Fe-deficiency (p = 0.57 and χ2 = 0.33), with a significant association of younger individuals (3.0–9.1 years) with Fe-deficiency (p < 0.05 and χ2 = 22.7).In addition, there is a significant positive correlation between Fe-deficiency with blood levels of Pb, Cu, and Zn (p < 0.05), (r = 0.43, 0.35, and 0.42, respectively) as compared to control group, this findings supported, by comparing the levels of the examined metals in both groups, in individuals whom close to heavy metals source (highway traffic or oil gas station), and found that the mean of the heavy metals level in close Fe-deficient group higher than in close Fe-replete group. 相似文献
996.
亚硝态氮是养殖水体中常见的胁迫因子.为探讨亚硝态氮对养殖蟹类的毒性作用,采用生物酶测定及聚丙烯酰胺凝胶电泳的方法,研究了水体中不同浓度(0.15,0.3,2,5,10,20mg/L)亚硝态氮胁迫下日本蟳肝胰腺消化酶活力的变化,以及高浓度(20mg/L)亚硝态氮胁迫对日本蟳同工酶表达的影响.结果表明:低浓度(0.15,0.3mg/L)的亚硝态氮胁迫对碱性蛋白酶,酸性蛋白酶,脂肪酶和淀粉酶活力均产生一定的诱导效应,且在处理7d时,除淀粉酶活力略低于对照组外,其他3种消化酶活力仍保持在较高的水平.较高浓度(2,5,10mg/L)亚硝态氮的短期胁迫(0.5~1d)会诱导酸性蛋白酶,碱性蛋白酶和脂肪酶活力的迅速升高,但随即快速下降.高浓度(20mg/L)的亚硝态氮胁迫对蛋白酶和淀粉酶活力表现出明显的抑制效应.处理7d时,胁迫浓度2mg/L及以上的实验组各消化酶活力与剂量浓度间均呈显著负相关关系.20mg/L亚硝态氮胁迫下,除肌肉中新增两条酶带(MDH-2和MDH-4)外,日本蟳鳃,肝胰腺,胃,心脏,卵,精子等组织中的α-淀粉酶(α-AMY)同工酶,乳酸脱氢酶(LDH)同工酶,苹果酸脱氢酶(MDH)同工酶和过氧化物酶(POD)同工酶均出现活性减弱或酶带数量减少现象.结果显示高浓度亚硝态氮胁迫对日本蟳消化酶活力和同工酶表达均表现出明显的抑制作用. 相似文献
997.
Examination of vapor above commercial sodium humate and above 10wt% aqueous humate solution by gas chromatography (GC) revealed the presence of chloroform and trichloroethylene. Further examination of the aqueous humate by the purge and trap procedure confirmed the association of chloroform and trichloroethylene with the humate. GC/mass spectrometry analyses of methylene chloride extract of the humate established the association of LMHs with the humate. Improved headspace capillary GC technique showed that the humate contained not only chloroform, trichloroethylene but several other LMHs in the range 190 to 4000ng·kg‐1. 相似文献
998.
A sensitive, accurate and reproducible method for the analysis of metoclopramide, a gastrointestinal drug, has been described. An isocratic HPLC elution method was employed which requires about 10 minutes to be performed. The concentration of metoclopramide hydrochloride preparations was found to be 95.1 ±0.3% and 94.21 ±0.25% in tablet and injection formulations, respectively. 相似文献
999.
A model for assessing approval of a beach for recreational water activity was proposed. The model is based upon a sanitary survey together with intensive microbiological monitoring three times a day, five times a week for a month. In highly populated areas, continuous surveys once a day, five days a week are needed in order to assure the cleanliness and safety of these beaches. Due to our intensive monitoring system, we can assure that Tel‐Aviv has one of the cleanest beaches near a metropolitan area in the Mediterranean Sea. 相似文献
1000.
The interaction between 33 commercial pesticides with hydroxypropyI‐β‐cyclodextrin (HPBCD) was studied by charge‐transfer reversed‐phase thin‐layer chromatography using aqueous sodium chloride solutions as eluents. Each pesticide interacted with HPBCD, their lipophilicity linearly decreased with increasing HPBCD concentration, the pesticide ‐ HPBCD complex (probably inclusion complex) always being more hydrophilic than the uncomplexed pesticide. In many cases the retention of pesticide increased with increasing concentration of salt in the eluent. This effect can be tentatively explained by the suppression of the dissociation of the polar groups in the solute molecules resulting in increased apparent lipophilicity. No significant correlation was found between lipophilicity and complex stability or between salting‐out effect and lipophilicity, that is other than hydrophobic forces are involved in the pesticide ‐ HPBCD interaction. 相似文献