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THz spectroscopic investigation of 2,4-dinitrotoluene 总被引:5,自引:0,他引:5
Yunqing Chen Haibo Liu Yanqing Deng Dunja Schauki Michael J. Fitch Robert Osiander Caroline Dodson James B. Spicer Michael Shur X.-C. Zhang 《Chemical physics letters》2004,400(4-6):357-361
We have investigated the terahertz (THz) spectrum of 2,4-DNT by using Fourier transform infrared spectroscopy in the 0.2–19.5 THz region. We also examined low-frequency intermolecular or phonon modes between 0.2 and 1.8 THz via THz time-domain spectroscopy. The extracted absorption coefficient and refractive index of an intermolecular band at 1.08 THz are 110 cm−1 and 1.67, respectively. Density functional theory (DFT) was applied to obtain structure and vibrational frequencies of 2,4-DNT. The calculated results are in agreement with the experimental data. Observed vibrational frequencies have been interpreted using DFT. Two intermolecular or phonon modes were identified at 1.08 and 2.52 THz. 相似文献
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P. Yu. Andreev G. A. Galstyan A. G. Galstyan 《Russian Journal of Organic Chemistry》2004,40(11):1630-1632
2,4-Dinitrotoluene reacts with ozone along two concurrent pathways: at the aromatic ring yielding stable against ozonolysis hydroperoxide, and at the methyl group with retention of the aromatic structure. The relative amount of products undergoing oxidation at the aromatic ring and at the methyl group depends on the ozonation conditions, especially on the process temperature.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 11, 2004, pp. 1678–1680.Original Russian Text Copyright © 2004 by Andreev, G. Galstyan, A. Galstyan. 相似文献
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T. Wolszakiewicz A. Książczak T. Książczak 《Journal of Thermal Analysis and Calorimetry》2004,77(1):353-361
Melting enthalpy and mixing enthalpy of binary system 2,4-dinitrotoluene and nitrocellulose were determined by DSC method.
The maximum value of mixing enthalpy was H
max
M=1.38 kJ mol−1 for molar fraction x
w24DNT = 0.501. The Flory-Huggins parameter (c) was estimated. The solubility curves and glass transition temperatures were predicted
and compared with the experimental results.
The measurements were performed for the samples with different times of storage at room temperature. The analysis of melting
peaks for the mixture leads to the conclusion that for the long periods of storage the melting of 2,4-dinitrotoluene takes
place in the confined spaces (pores) and unconfined space (bulk). The crystallization and melting is observed during the short
time of storage in mixtures with low nitrocellulose content and in the case of mixtures with a large amount of NC the glass
transition is additionally observed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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In order to investigate the excretion and distribution of 2,4-DNT in the rat, 3H-2,4-DNT was synthesized by nitration reaction of 3H-toluene. About 21.3 per cent of the single orally administered radioactivity was excreted in the 1st day-faeces. The amounts of radioactivity in the 2nd day- and 3rd day-faeces were to be about 4.1 and 1.1 per cent, respectively. About 13.5 per cent of the radioactivity administered was excreted in the 1st day-urine, but after the 2nd day the excretion of radioactivity was to be trace. In all, about 46 per cent of the radioactivity administered was excreted in the faeces and urine during the 7 days. Seven days after administration relatively high levels of radioactivity were retained in adipose tissue, skin, and liver, however, the amounts of remaining radioactivity were to be only 1.5, 0.6 and 0.4 per cent, respectively. The amounts of radioactivity of the other organs were to be trace. 相似文献
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Berkant Kayan A.Murat Gizir Ferruh Erdogdu 《Reaction Kinetics and Catalysis Letters》2004,81(2):241-249
The rates of wet air oxidation of 2-nitrotoluidine and 2,4-dinitrotoluene in the presence of excess oxygen and at different
temperatures and oxygen pressures was investigated. Oxidation experiments were carried out at temperatures between 180 and
225oC and oxygen partial pressures of 1,0-3,0 MPa, in a 280 mL glass vessel-inserted stainless steel reactor. Copper sulfate (CuSO4 .5H2O) was used as a catalyst, and the effect of catalyst loading was studied by varying the concentration: 0.75, 2.5 and 25 mg/L
as Cu2+. Addition of Cu2+ ions in the reaction media accelerated 2-nitrotoluidine oxidation nearly ten times even if it exists in trace amount in the
reaction medium (0.75 ppm Cu2+). Unfortunately copper did not show catalytic effect for the oxidation of 2,4-dinitrotoluene.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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In this work, we demonstrate for the first time that 4-methyl-5-nitrocatechol (4M5NC) and 2,4,5-trihydroxytoluene (2,4,5-THT), two compounds obtained from the 2,4-DNT biodegradation are recognized by polyphenol oxidase as substrates. An amperometric biosensor is described for detecting these compounds and for evaluating the efficiency of the 2,4-DNT conversion into 4M5NC in the presence of bacteria able to produce the 2,4-DNT-biotransformation. The biosensor format involves the immobilization of polyphenol oxidase into a composite matrix made of glassy carbon microspheres and mineral oil. The biosensor demonstrated to be highly sensitive for the quantification of 4M5NC and 2,4,5-THT. The analytical parameters for 4M5NC are the following: sensitivity of (7.5 ± 0.1) × 105 nAM−1, linear range between 1.0 × 10−5 and 8.4 × 10−5 M, and detection limit of 4.7 × 10−6 M. The sensitivity for the determination of 2,4,5-THT is (6.2 ± 0.6) × 106 nAM−1, with a linear range between 1.0 × 10−6 and 5.8 × 10−6 M, and a detection limit of 2.0 × 10−7. Under the experimental conditions, it was possible to selectively quantify 4M5NC even in the presence of a large excess of 2,4-DNT. The suitability of the biosensor for detecting the efficiency of 2,4-DNT biotransformation into 4M5NC is demonstrated and compared with HPLC-spectrophotometric detection, with very good correlation. This biosensor holds great promise for decentralized environmental testing of 2,4-DNT. 相似文献
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Liquid-phase oxidation of 2,4-dinitrotoluene with ozone in the presence of acetic anhydride as stop reagent and manganese(II) acetate as catalyst was studied. The major products of oxidation with ozone in acetic anhydride are 2,4-dinitrobenzyl alcohol (65.8%) and 2,4-dinitrobenzaldehyde (18.8%) in the form of the corresponding acetates. A reaction scheme accounting for the results obtained is considered. 相似文献
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V. Hajdu M. Varga G. Muránszky G. Karacs F. Kristály B. Fiser B. Viskolcz L. Vanyorek 《Materials Today Chemistry》2021
Cobalt, copper, and nickel ferrite spinel nanoparticles have been synthesized by using a combination of sonochemical treatment and combustion. The magnetic nanoparticles have been used as supports to prepare ~4 wt% palladium catalysts. The ferrites were dispersed in an ethanolic solution of Pd(II) nitrate by ultrasonication. The palladium ions were reduced to metallic Pd nanoparticles, which were then attached to the surface of the different metal oxide supports. Thus, three different catalysts (Pd/CoFe2O4, Pd/CuFe2O4, Pd/NiFe2O4) were made and tested in the hydrogenation of 2,4-dinitrotoluene (DNT). A possible reaction mechanism, including the detected species, has been envisaged based on the results. The highest 2,4-diaminotoluene (TDA) yield (99 n/n%) has been achieved by using the Pd/NiFe2O4 catalyst. Furthermore, the TDA yield was also reasonable (84.2 n/n%) when the Pd/CoFe2O4 catalyst was used. In this case, complete and easy recovery of the catalyst from the reaction medium is ensured, as the ferrite support is fully magnetic. Thus, the catalyst is very well suited for applicationy in the hydrogenation of DNT or other aromatic nitro compounds. 相似文献
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The authors have prepared amino-functionalized carbon dots (AC-dots) and applied them to fluorescently label a molecularly imprinted polymer (MIP) prepared by using 2,4-dinitrotoluene (DNT) as a template. Since DNT can retard vinyl polymerization, poly(methyl acrylate-co-acrylic acid) was used as a monomer. Non-imprinted polymers (NIPs) were also synthesized in order to compare data. As expected, MIPs exhibit higher adsorption than NIPs, with imprinting efficiencies ranging from 2 to 2.5. DNT is specifically captured by the cavities in the MIP and interact with AC-dots on the surface, resulting in quenching of the fluorescence of the AC-dots. Response to DNT reaches equilibrium within ~30 min. The method has a dynamic range that extends from 1 to 15 ppm, and allows for quantitation of DNT in aqueous solutions, with a detection limit of 0.28 ppm. Selectivity tests conducted in presence of DNT analogs demonstrated the selective recognition of DNT. 相似文献
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M Mori T Kawajiri M Sayama T Miyahara H Kozuka 《Chemical & pharmaceutical bulletin》1989,37(7):1904-1908
The metabolism of 2,4-dinitrotoluene (2,4-DNT), 2,4-dinitrobenzyl alcohol (2,4-DNB), 2,4-dinitrobenzaldehyde (2,4-DNBAl), 2,6-DNT, 2,6-DNB and 2,6-DNBAl in the microsomal and cytosol fractions prepared from unfortified male Wistar and male Sprague-Dawley (S.D.) rat livers was investigated. Data obtained by high-performance liquid chromatography (HPLC) indicated that the products of dinitrotoluenes (2,4-DNT and 2,6-DNT), dinitrobenzyl alcohols (2,4-DNB and 2,6-DNB), and dinitrobenzaldehydes (2,4-DNBAl and 2,6-DNBAl) in the microsomal and cytosol preparations containing nicotinamide adenine dinucleotide phosphate (NAD(P] and reduced NAD(P)(NAD(P)H) were dinitrobenzyl alcohols (2,4-DNB and 2,6-DNB), dinitrobenzaldehydes (2,4-DNBAl and 2,6-DNBAl), and dinitrobenzoic acids (2,4-DNBA and 2,6-DNBA), and dinitrobenzyl alcohols (2,4-DNB and 2,6-DNB), respectively. From these results, it was concluded that the dinitrobenzaldehydes (2,4-DNBAl and 2,6-DNBAl) were intermediates in the oxidations of dinitrobenzyl alchols (2,4-DNB and 2,6-DNB) to dinitrobenzoic acids (2,4-DNBA and 2,6-DNBA), and that the oxidations of dinitrobenzyl alcohols (2,4-DNB and 2,6-DNB) to dinitrobenzaldehydes (2,4-DNBAl and 2,6-DNBAl) and the reductions of dinitrobenzaldehydes to dinitrobenzyl alcohols (2,4-DNB and 2,6-DNB) were reversible.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Hua Xiao Ruiping Liu Xu Zhao Jiuhui Qu 《Journal of molecular catalysis. A, Chemical》2008,286(1-2):149-155
Manganese catalytic ozonation of 2,4-dinitrotoluene (DNT) in the presence of oxalic acid was studied. The addition of manganese ion (Mn2+) or oxalic acid alone in ozonation process did not enhance DNT degradation, but the addition of Mn2+ coupled with oxalic acid accelerated degradation of DNT. The DNT degradation efficiency was influenced by carbonate in the catalytic ozonation process. Kinetics study showed that Mn2+ catalytic ozonation significantly promoted the decomposition of ozone. Experimental results of electron spin resonance (ESR) demonstrated that addition of Mn2+ and oxalic acid produced much hydroxyl radicals in catalytic ozonation system than that in single ozonation system. These results suggested that catalytic ozonation followed hydroxyl radical-type mechanism. Mn2+ promoted decomposition of ozone to produce hydroxyl radical and it was oxidized into manganese oxide. Manganese oxide was reduced into Mn2+ by oxalic acid, which is the key step of catalytic process. Based on above results, a cycle catalytic mechanism of Mn2+ was proposed. Intermediates were determined by HPLC and GC–MS, and they mainly included aromatic organics and aliphatic carboxylic acids. 相似文献
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V. I. Manov-Yuvenskii B. A. Redoshkin G. P. Belyaeva B. K. Nefedov 《Russian Chemical Bulletin》1981,30(3):455-458
Conclusions In the carbonylation of 2,4-dinitrotoluene using CO the extremal character of the yield of 1-methylbenzene 2,4-diisocyanate as a function of the temperature and pyridine concentration is apparently caused mainly by the coupling of two factors: an increase in the synthesis rate of the isocyanate with increase in either the reaction temperature or the pyridine concentration in solution and the instability of the isocyanate under the conditions of its synthesis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 614–617, March, 1981. 相似文献
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Mohsin Qureshi Syed Ashfaq Nabi Ali Mohammad Pushkin Mohammad Qureshi 《Journal of solid state chemistry》1982,44(2):186-191
The kinetics and mechanism of the reaction of 2,4-dinitrotoluene with diphenylamine were studied in the solid state. The reaction product is a charge transfer complex with a localized intermolecular interaction as shown by uv and ir spectroscopy. The solid-state studies were complemented by some NMR studies in CCl4. A novel feature of the study reveals that diphenylamine in this case is a much more powerful n donor than a π donor. 相似文献
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The kinetics and the mechanism of the liquid-phase oxidation of 2,4-dinitrotoluene with ozone in the presence of manganese(II) acetate have been investigated. The major products of 2,4-dinitrotoluene oxidation with ozone in acetic anhydride are 2,4-dinitrobenzyl acetate (65.8%) and 2,4-dinitrobenzylidene diacetate (18.8%). The effect of the manganese(II) acetate concentration on the selectivity of substrate oxidation at the methyl group is reported. A redox catalysis mechanism providing an explanation to experimental data is considered. 相似文献