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1.
C. A. Laue D. Gates-Anderson T. E. Fitch 《Journal of Radioanalytical and Nuclear Chemistry》2004,261(3):709-717
This review focuses on dissolution/reaction systems capable of treating uranium metal waste to remove its pyrophoric properties.
The primary emphasis is the review of literature describing analytical and production-scale dissolution methods applied to
either uranium metal or uranium alloys. A brief summary of uranium's corrosion behavior is included since the corrosion resistance
of metals and alloys affects their dissolution behavior. Based on this review, dissolution systems were recommended for subsequent
screening studies designed to identify the best system to treat depleted uranium metal wastes at Lawrence Livermore National
Laboratory (LLNL).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
P. Marage M. Aderholz P. Allport N. Armenise J. P. Baton M. Berggren D. Bertrand V. Brisson F. W. Bullock W. Burkot M. Calicchio E. F. Clayton T. Coghen A. M. Cooper-Sarkar O. Erriquez P. J. Fitch G. Gerbier J. Guy F. Hamisi P. O. Hulth G. T. Jones P. Kasper H. Klein R. P. Middleton D. B. Miller M. M. Mobayyen D. R. O. Morrison S. Natali M. Neveu S. W. O'Neale M. A. Parker P. Petiau J. Sacton R. A. Sansum E. Simopoulou C. Vallée K. Varvell A. Vayaki W. Venus H. Wachsmuth J. Wells W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,31(2):191-197
The cross section for coherent production of a single π? meson in charged current antineutrino interactions on neon nuclei has been measured in BEBC to be (175±25) 10?40 cm2/neon nucleus, averaged over the energy spectrum of the antineutrino wide band beam at the CERN SPS; this corresponds to (0.9±0.1) % of the total charged current \(\bar v_\mu \) cross section. The distributions of kinematical variables are in agreement with theoretical predictions based on the PCAC hypothesis and the meson dominance model; in particular, theQ 2 dependence is well described by a propagator containing a massm=(1.35±0.18) GeV. The absolute value of the cross section is also in agreement with the model. This analysis thus provides a test of the PCAC hypothesis in the antineutrino energy range 5–150 GeV. 相似文献
3.
A dense-phase latex rubber tube and a polyporous propylene hollow-fiber membrane module (HFMM) were investigated for control
of benzene-contaminated gas streams. The abiotic mass flux observed through the latex tube was 3.9–13 mg/(min·m2) for 150 ppm of benzene at various gas and liquid flow rates, while a 100-fold lower mass flux was observed in the HFMM.
After seeding with an aromatic-degrading culture enriched from activated sludge, the observed removal was 80% of 150 ppm,
corresponding toa mass flux of 45 mg/(min·m2). The observed mass flux through the HFMM during biofiltration also rose, to 0.4 mg/(min·m2). Because the HFMM had a 50-fold higher surface area than the latex tube, the observed ben zene removal was 99.8%. Compared
to conventional biofilters, the two reactors had modest elimination capacities, 2.5–18 g/(m3·h) in the latex tube membrane bioreactor and 4.8–58 g/(m3·h) in the HFMM. Although the HFMM had a higher elimination capacity, the gas-phase pressure drop was much greater. 相似文献
4.
5.
White DB Tippens WB Abegg R Baldisseri A Boudard A Briscoe W Fabbro B Garçon M Hermes EA Jacobs WW Kessler RS Lytkin L Mayer B Nefkens BM Niebuhr C Petrov AM Poitou J Saudinos J Tomasi-Gustafsson E van der Schaaf A van Oers WT Vigdor SE Wang M 《Physical review D: Particles and fields》1996,53(11):6658-6661
6.
Garner DK Fitch SB McAlexander LH Bezold LM Arif AM Berreau LM 《Journal of the American Chemical Society》2002,124(34):9970-9971
The synthesis and properties of mononuclear zinc methoxide ([(ebnpa)Zn-OCH3]ClO4) (1) and hydroxide ([(ebnpa)Zn-OH]ClO4) (2) complexes of a new mixed nitrogen/sulfur ligand (ebnpa = N-2-(ethylthio)ethyl-N,N-bis(6-neopentylamino-2-pyridylmethyl)amine) are reported. The structures of 1 and 2 were determined by X-ray diffraction. Each possesses a single zinc-coordinated anion (methoxide or hydroxide) and exhibits an overall trigonal bipyramidal geometry. Structural and spectroscopic studies indicate the presence of two hydrogen-bonding interactions involving the oxygen atom of the zinc-bound anion in each complex. Treatment of [(ebnpa)Zn-OH]ClO4 with CH3OH results in the formation of an equilibrium mixture of 1 and 2. 1H NMR spectroscopic methods were used to examine the equilibrium as a function of temperature, yielding KMe (304 K) = 0.30(8), DeltaHMe = -0.9(1) kcal/mol, and DeltaSMe = -5(1) eu. The negative enthalpy indicates that spontaneous zinc alkoxide formation from a hydroxide precursor occurs in this system at low temperature. Using the experimentally determined DeltaHMe value, we found the homolytic Zn-O bond dissociation energy (BDE) in the Zn-OCH3 unit to be approximately -14 kcal/mol relative to the Zn-O BDE in the Zn-OH unit. 相似文献
7.
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
8.
The structure of Li4?2xSi1?xSxO4 (x ≈ 0.32) has been determined from neutron powder diffraction studies at room temperature, 350, and 700°C. This compound, which is a member of the series of ionic-conducting solid solutions formed between Li4SiO4 and Li2SO4, is isostructural with Li3PO4. The space group is Pmnb, with a = 6.1701(1), b = 10.6550(2), c = 5.0175(1)Å at room temperature. The distribution of lithium ions suggests the occurrence of a defect cluster in which the inclusion of an interstitial lithium ion causes displacements of the adjacent lithium ions of the normal Li3PO4 structure. There appears to be little variation of the structure with temperature. 相似文献
9.
Michael T. Carver Franoise Candau Robert M. Fitch 《Journal of polymer science. Part A, Polymer chemistry》1989,27(7):2179-2188
A study of the effect of the various solution components on the kinetics of the polymerization of acrylamide in water/oil (w/o) microemulsions has been performed. For the polymerizations with toluene as the continuous phase, both the rate of polymerization, Rp, and the molecular weight of the polyacrylamide were found to be first order in monomer concentration. Furthermore, for the low temperatures (10°C) involved in these experiments, nondegradative chain transfer to monomer appears to be insignificant. When the continuous-phase solvent was changed, an exponential dependence, X, of Rp on the incident light intensity in the order of toluene (X = 1.06) > heptane (X = 0.73) > benzene (X = 0.55) was found. Thus, the monoradical termination found in the toluene microemulsions is likely due to degradative transfer to toluene, forming a stable benzyl radical, while polymerization in benzene (no labile hydrogen atoms) leads to biradical termination 相似文献
10.
J. C. Salamone B. Snider W. L. Fitch 《Journal of polymer science. Part A, Polymer chemistry》1971,9(6):1493-1504
The mechanism of the spontaneous polymerization of 4-vinylpyiridine on quaternization or protonation has been investigated. Results indicate that initiation is caused by the nucleophilic attack of 4-vinylpyridine on the double bond of 4-vinylpyridinium ion. It was shown that halide ions do not contribute significantly to the initiation. In the case of acid salts of 4-vinylpyridine a hydrogen-transfer polymerization occurred to give an ionene polymer with pyridinium units in the main chain. The “matrix” polymerization of 4-vinylpyridine on poly(phosphoric acid) or poly(acrylic acid) also resulted in ionene formation. Conditions under which stable 4-vinylpyridinium salts can be obtained are discussed. 相似文献