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A low‐voltage operable, highly sensitive, and selectively responsive polymer for the detection of nitroaromatic explosives is investigated. Resistive devices are fabricated by simple spin‐coating on flexible and transparent substrates in addition to silicon substrates and are stable under ambient temperature and oxygen levels before exposure to the nitroaromatics. After exposure to 2,4,6‐trinitrotoluene (TNT), the devices show increased conductance, even with picogram (pg) quantities of TNT, accompanied by a confirming color change from colorless to deep red. The relative conductance increase per unit exposure is the highest yet reported for TNT. Aromatic anion salts, on the other hand, do not induce any electronic responses. 1H NMR and microscopic analyses show chemical interactions and morphological changes correlated with the electronic responses, some of which are specific to TNT in relation to other nitroaromatics. The binding constant for the imidazole rings and TNT is on the order of tens of M ?1. The materials are promising for rapid indication of exposure to nitroaromatic compounds. 相似文献
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This paper summarizes the results of research on the treatment of synthetically prepared aqueous solutions of trinitrotoluene (TNT) and cyclotrimethylene–trinitramine (RDX) in the weight ratio 70%/30% representing a typical munitions wastewater, by a combination of ozone and ultrasound. A parametric study investigated the relationship among the variables: (1) initial solution pH (5.84 → 10.0); (2) ultrasound power level (5 → 50 watts at 852.0 to 863.0 kHz);(3) ultrasound frequency level (60.6 → 1,007.0 kHz); (4) solution concentration (70/30 mg/l TNT/RDX solutions volumetrically diluted with distilled water in the ratios 1/0, 1/1, 1/3); (5) reaction temperature (25 → 59°C). Removal rates of both TNT and TOC increased directly with increases in reaction temperature and initial solution pH. Likewise, increased sound power level produced enhanced system kinetic responses; however, these were attributed to reaction mass temperature increases. Ultrasound was found to inhibit reaction kinetics at high temperatures and pH because it promoted radical–radical extinguishment reaction. 相似文献
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To remove the nitro aromatic compounds (NACs) and SO32? from distillate of 2,4,6‐trinitrotoluene (TNT) red water, the carboxylated and aminated polystyrene (PSt) microspheres were used as adsorbents. GC‐MS and HPLC analysis were used to determine the types and concentrations of NACs before and after adsorption. The carboxylated PSt, which was prepared by modifying PSt with phthlandione (PA), could remove the neutral NACs including 2,6‐dinitrotoluene (2,6‐DNT), 2,4‐dinitrotoluene (2,4‐DNT), 1,3,5‐trinitrobenzene (1,3,5‐TNB), and 2,4,6‐trinitrotoluene (2,4,6‐TNT), with the acid 2,4‐dinitrophenol (2,4‐DNP) and SO32? remained in the distillate. The aminated PSt that was synthesized by activating PSt with chloroacetyl chloride follow by reaction with 1,2‐ethanediamine (EDA) could remove all the NACs and SO32?. The results suggested that EDA‐PSt adsorbed the NACs though multimode interactions, i.e., hydrogen bond and electrostatic attraction. After adsorption using EDA‐PSt, chemical oxygen demand (COD) was reduced from 86.1 to 11.2 mg L?1, and a colorless, transparent, and nontoxic solution with neutral pH value was obtained. Five grams of EDA‐PSt could purify 1600 cm3 of distillate of TNT red water, and the adsorbents could be recycled by elution with methanol to desorb the neutral NACs followed by elution with 0.1 mol L?1 NaOH to wash off 2,4‐DNP and SO32?. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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利用由磷酸-微波法处理剩余活性污泥制得吸附剂,研究了它对三硝基甲苯红水的吸附性能,考察了废水pH值、吸附时间、吸附剂投加量对吸附效果的影响,实验结果表明,该吸附剂2个最佳pH值范围为4左右和9左右,吸附平衡时间为60min;当吸附剂的投加量为8%时,其CODCr去除率达到了85.7%。 相似文献
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