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J.B. Mock G.A. Thomas D.E. Moncton M. Kaplan 《Journal of Physics and Chemistry of Solids》1978,39(3):253-254
Using a high-speed photographic technique, we have recorded directly the crystalline distortion associated with a first-order phase transition in tetrathiafulvalenium-bis-ditholene (Cu). This structural distortion, at a temperature of 238 K, has been observed as a crystal motion through an angle of the order of 10°. The phase change may be important in establishing the one-dimensional magnetic character of the crystal that leads to a spin-dimerization transition at a temperature of 12 K. 相似文献
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Hironori Fukukawa Theodore J. Mock 《International Journal of Approximate Reasoning》2012,53(2):190-199
This paper examines possible differences in auditors’ performance when they make belief-based versus probability-based risk assessments by focusing on two phases of the financial statement audit process: the assessment of two attributes of audit evidence (‘strength’ and ‘direction’) and the aggregation of evidence. Based on an experiment in which 48 experienced auditors participated, three important findings were observed. First, there was no significant difference in the mean assessment of strength of evidence measured using the likelihood ratio. However, the difference in the assessed direction of evidence, that is whether the evidence is interpreted as being confirming or disconfirming, is significant for one of the cases examined. This result shows that auditors making belief-based assessments are able to assess the direction of the evidence more accurately than auditors making probability-based assessments. Third, the auditors’ aggregation of evidence was not in accordance with ‘AND’ logic for either auditors making belief-based or probability-based assessments. These empirical results raise issues which need to be addressed in practice and in future research. 相似文献
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Sanford T.W.L. Spielman R.B. Allshouse G.O. Chandler G.A. Fehl D.L. Stygar W.A. Struve K.W. Deeney C. Nash T.J. Seamen J.F. Mock R.C. Gilliland T.L. McGurn J.S. Jobe D.O. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1998,26(4):1086-1093
Doubling the number of tungsten wires from 120 to 240, keeping the mass fixed, increased the radiated X-ray power relative to the electrical power at the insulator stack of the Z accelerator by (35±15)% for 8.75- and 20-mm radii Z-pinch wire arrays. One-dimensional radiation magneto hydrodynamic calculations suggest that the arrays were operating in a quasi “plasma-shed” regime, where the plasma generated by the individual wires partially merge prior to the inward implosion of the entire array 相似文献
15.
Electrical conduction in nanostructured 10 mol% Sr- and 15 mol% Mg-doped lanthanum gallate was investigated. The grain boundary conductivity shows mixed ionic and electronic conduction, while the grain conductivity shows ionic conduction. This is attributed to the increase of the contribution of the electron-hole in the grain boundary by the space charge effect. The overall electrical conductivity is governed by the grain boundary conductivity such that nanostructured lanthanum gallate becomes a mixed conductor. 相似文献
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Steffen Gilbert Michael Knorr Stefan Mock Ulrich Schubert 《Journal of organometallic chemistry》1994,480(1-2):241-254
Photochemical reaction of (CO)2(dppe)Fe(H)(SiR3) with HSiR3 (SiR3 = Si(OMe)3, Si(OEt)3, SiMe3, SiMe2Ph, SiPh3) yields the trihydrido silyl complexes (CO)(dppe)FeH3(SiR3 ). The analogous complexes (PR′Ph2)3 FeH3(ER3) are prepared by reaction of the H2 -complexes (PR′Ph2)3FeH2(H2) with HER3 (ER3 = SiMe3, SiMC2Ph, SiMePh2, SiPh3, Si(Me2)OSi(Me2)H, SnPh3, SnEt3). Additional derivates of (CO) (dppe)FeH3(SiR3) (SiR3 = SiMePh2) and (PR′Ph2)3FeH3(SiR3) (SiR3 = Si(OMe)3, SiH2Ph, SiHPh2, Si(OEt)3, SiMePhCl) are accessible by silane exchange starting from (CO)(dppe)FeH3(SiMe3) and (PR′Ph2) 3FeH3(SiMe3). (PBuPh2)3FeH3(SiMePh2) was also prepared from (PBuPh2)3FeH2(N2) and HSiMePh2, and (PBuPh2)3FeH3(SnMe3) from (PBuPh2)3FeH2(H2) and Me3SnCl. The complex (PBuPh2) 3FeH3(SnMe3) crystallizes as a toluene solvate in the cubic space group I
3d and shows crystallographically imposed C3-symmetry. The complexes (CO)2 (dppe)Fe(H)(SiR3) and (PR′Ph2)3FeH3(ER3) are highly dynamic in solution. Low temperature NMR measurements and the E, Fe, H coupling constants strongly indicate that the exchange mechanism involves η2-HER3 ligands. 相似文献
17.
Dicarbomethoxy- and dichlorocarbene add to 1,2,2-trimethylbicyclo[1.1.0]butane to give derivatives of 2,3,3-trimethylpenta-1,4-diene. These products are not predicted by the mechanism proposed earlier. A new mechanism is suggested. 相似文献
18.
Experimental evidence is presented demonstrating ionization of an exciton gas as its density is lowered at constant temperature. The measurements are made by monitoring the luminescence from a photo-excited sample of high-purity, single-crystal germanium in which the exciton density is nearly uniform. 相似文献
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