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961.
The effectiveness of applying a pulsed corona discharge to the destruction of olfactory pollution in air was investigated.
This paper presents a comparative study of the decomposition of three representative sulfide compounds in diluted concentrations:
hydrogen sulfide (H2S), dimethyl sulfide (DMS), and ethanethiol (C2H5SH), which could be completely removed when a sufficient but reasonable energy density was deposited in the gas. DMS showed
the lowest energy cost (around 30 eV/molecules); C2H5SH and H2S had an EC of respectively 45 eV and 115 eV. The efficiency of the non-thermal plasma process increased with decreasing the
initial concentration of sulfide compounds, while the energy yield remained almost unchanged. SO2 was the only identified byproduct of H2S decomposition, but the sulfur balance suggests the formation of undetected SO3. The byproducts analyzed during the degradation of DMS and C2H5SH enabled to propose a reaction mechanism, starting with radical attack and breaking of C–S bonds. 相似文献
962.
Jaime?WisniakEmail author René?D.?Peralta Ramiro?Infante Gladis?Cortez 《Journal of solution chemistry》2005,34(2):171-183
Densities of the ternary system 1,4-dioxane + butyl acrylate + ethyl acrylate and its binary butyl acrylate + ethyl acrylate have been measured in the whole composition range, at 298.15 K and atmospheric pressure, using an Anton Paar DMA 5000 oscillating U-tube densimeter. The calculated excess molar volumes of the binary system are positive and were correlated with the Redlich–Kister equation and with a series of Legendre polynomials. Several models were used to correlate the ternary behavior from the excess molar volume data of their constituent binaries and were found equally good to fit the data. The best fit was based on a direct approach, without information on the component binary systems. 相似文献
963.
Shoichi Katsuta Hirokazu Wakabayashi Mariko Tamaru Yoshihiro Kudo Yasuyuki Takeda 《Journal of solution chemistry》2007,36(4):531-547
Equilibria concerning picrates of tetraalkylammonium ions (Me4N+, Et4N+, Pr4N+, Bu4N+, Bu3MeN+) in a dichloromethane−water system have been investigated at 25 ∘C. The 1:1 ion-pair formation constants (K
IP,o
o) in dichloromethane at infinite dilution were conductometrically determined. The distribution constants (K
D
o) of the ion pairs and the free cations between the solvents were determined by a batch-extraction method. The K
IP,o
o value varies in the cation sequence, Bu4N+ ≈ Pr4N+ ≈ Et4N+ < Bu3MeN+ < < Me4N+; this trend is explained by the electrostatic cation−anion interaction taking into account the structures of the ion pairs
determined by density functional theory calculations. For the ion pairs of the symmetric R4N+ cations, there is a linear positive relationship between log10
K
D
o and the number of methylene groups in the cation (N
CH
2). The ion pair of asymmetric Bu3MeN+ has a higher distribution constant than that expected from the above log10
K
D
o
versus
N
CH
2 relationship. These cation dependencies of log10
K
D
o for the ion pairs are explained theoretically by using the Hildebrand-Scatchard equation. For all the cations, the log10
K
D
o value of the free cation increases linearly with N
CH
2; the variation of log10
K
D
o is discussed by decomposing the distribution constant into the Born-type electrostatic contribution and the non-Born one,
and attributed to the latter that is governed by the differences in the molar volumes of the cations. The cation dependencies
of the ion-pair extractability and ion pairing in water are also discussed.
An erratum to this article can be found at 相似文献
964.
A series of new complexes {2,6-bis[1-((2-methyl-4-methoxyphenyl)imino)ethyl]pyridine}Cl2 [M=Fe(II) (2), Co(II) (3), Ni(II) (4), Cu(II) (5), Zn(II) (6)] have been synthesized. At 25°C, using 500 equiv of methylaluminoxane (MAO), the activities of Fe(II), Co(II) catalysts can reach 4.02 ×106 g/mol-Fehatm for ethylene polymerization and 3.98×105 g/mol-Cohatm for ethylene oligomerization. The effects of polymerization conditions such as reaction temperature, Al/M molar ratio and time on the activity of catalyst have been explored. 相似文献
965.
Summary. Two main types of binary systems with distinctive solubility behavior under sub- and supercritical conditions were used to
subdivide ternary water-salt systems into three classes. Characteristic features of solubility behavior and phase equilibria
in ternary water-salt systems of each class at temperatures above 200°C are discussed on the basis of available experimental
data and some conclusions obtained as a result of theoretical derivation of fluid and complete phase diagrams.
Corresponding author. E-mail: Valyashko@IGIC.RAS.RU
Received September 25, 2002; accepted (revised) November 28, 2002
Published online April 24, 2003
RID="a"
ID="a" Dedicated to Prof. Dr. H. Gamsjaeger on the occasion of his 70th birthday anniversary 相似文献
966.
Spirobenzopyran 1 , with the 3-(diethoxymethylsilyl)-propyl group at the N atom, was synthesized. The condensation reaction of the spiropyran 1 and diethoxydimethylsilane gave oligomeric poly(dimethylsiloxane) with the spiropyran moiety in the side chain. The oligomer was photochromic; its colour changed from colorless to purple-red on uv irradiation and the color faded on visible irradiation or on standing in the dark. The half-decay time of the thermal decoloration was about twice that of monomeric spiropyran dissolved in the dimethylsiloxane oligomer. Photochromic poly(dimethylsiloxane) with the spirooxazine moiety in the side chain was also prepared. 相似文献
967.
Shey-Huei Sheu 《The Journal of the Operational Research Society》1991,42(4):331-341
A generalization of the block replacement policy (BRP) is proposed and analysed for a multi-unit system which has the specific multivariate distribution. Under such a policy an operating system is preventively replaced at times kT (k = 1, 2, 3,...), as in the ordinary BRP, and the replacement of the failed system at failure is not mandatory; instead, a minimal repair to the component of the system can be made. The choice of these two possible actions is based on some random mechanism which is age-dependent. The cost of the ith minimal repair of the component at age y depends on the random part C(y) and the deterministic part Ci(y). The aim of the paper is to find the optimal block interval T which minimizes the long-run expected cost per unit time of the policy. 相似文献
968.
Toshikazu Kimura 《The Journal of the Operational Research Society》1991,42(7):595-603
This paper deals with refining Cosmetatos's approximation for the mean waiting time in an M/D/s queue. Although his approximation performs quite well in heavy traffic, it overestimates the true value when the number of servers is large or the traffic is light. We first focus on a normalized quantity that is a ratio of the mean waiting times for the M/D/s and M/M/s queues. Using some asymptotic properties of the quantity, we modify Cosmetatos's approximation to obtain better accuracy both for large s and in light traffic. To see the quality of our approximation, we compare it with the exact value and some previous approximations. Extensive numerical tests indicate that the relative percentage error is less than 1% for almost all cases with s ≤ 20 and at most 5% for other cases. 相似文献
969.
Toshikazu Kimura 《The Journal of the Operational Research Society》1991,42(11):959-970
We provide two distribution-dependent approximations for the mean waiting time in a GI/G/s queue. Both approximations are weighted combinations of the exact mean waiting times for the GI/M/s and M/D/s queues each of which has the same mean service time and traffic intensity as in the approximating GI/G/s queue. The weights in the approximations are expressed by the service-time c.d.f. and the first two moments of interarrival and service times. To examine the performance of our approximations, they are numerically compared with exact solutions and previous two-moment approximations for various cases. Extensive numerical comparisons indicate that the relative percentage errors of the approximations are of the order of 5% in moderate traffic and 1% in heavy traffic, except for extreme cases. 相似文献
970.