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461.
Giles GI Giles NM Collins CA Holt K Fry FH Lowden PA Gutowski NJ Jacob C 《Chemical communications (Cambridge, England)》2003,(16):2030-2031
Integrated catalysts as redox sensitisers towards cancer. 相似文献
462.
Holt CB 《Cryo letters》2003,24(5):323-330
Three substances have been tested for ice nucleation inhibition. These were an antifreeze protein AFP III from the fish Macrozoarces americanus, an antifreeze glycoprotein AFGP from the fish Dissostichus mawsoni, and an 80% hydrolysed poly(vinyl alcohol) with a molecular weight of 9 to 10 kD. A nucleation spectrometer was used to test nucleation inhibition at a range of concentrations against two types of ice nuclei: those present in tap water and a bacterial nucleator from Pseudomonas syringae. The PVA reduced the nucleation temperature of tap water and the bacterial dispersions at all the concentrations which were tested. The AFGP reduced the nucleation temperature of tap water but enhanced the nucleation activity of the bacterial nucleators. At low concentrations the AFP III reduced the nucleation temperature of both tap water and the bacterial nucleator. At high concentrations the AFP III enhanced the nucleation temperature of the bacterial nucleator and broadened the nucleation spectrum of the tap water to encompass the nucleation spread of the control. The possible mechanisms of nucleation suppression and enhancement are discussed. 相似文献
463.
The thermal degradation of four different forms of cellulose in nitrogen has been studied by using a thermobalance. In TG experiments a total weight loss at 900°C was 80% in the cases of film and pulp samples and 83% for two powder forms. The results for the isothermal degradation of the four samples at 270°C are plotted as degree of degradation α against reduced time t/t0.5 and compared with the master plots of Sharp, Brindley, and Achar. The experimental data fit most closely the plot for the Avrami-Erofeev equation in the form kt = {–ln (1–α)}1/n where n = 2. An activation energy of 144 kJ/mole has been found for the degradation of one of the celluloses from the results of isothermal runs at six different temperatures. It is postulated here that the thermal degradation occurs by random nucleation and nucleus growth in the cellulose fibrils so as to yield a carbon whose microporous structure is a replica of the pore system in the parent cellulose. 相似文献
464.
P.S.L. BoothG.R. Court B. CravenR. Gamet P.J. HaymanJ.R. Holt A.P. HuftonJ.N. Jackson J.H. NoremW.H. Range 《Physics letters. [Part B]》1972
The polarized target asymmetry parameter has been measured for single πo photoproduction from hydrogen at 4 GeV and values of four-momentum transfer squared between −0.15 (GeV/c)2 and −1.8 (GeV/c)2. 相似文献
465.
466.
P.S.L. Booth L.J. Carroll J.R. Holt J.N. Jackson W.H. Range K.A. Sprakes J.R. Wormald 《Nuclear Physics B》1974,71(2):211-216
Differential cross sections for the process γp → pη have been measuredd at c.m. angles of 28°, 35° and 42° at incident energies between 2 GeV and 2.8 GeV. Data from an earlier experiment below 2 GeV have been re-analysed and corrected. The whole set of data is compared with the form (s?M2)2 dσ/dt, which fits data at higher energies. There is good agreement above 2 GeV, particularly at the largest angle, but strong departures below. 相似文献
467.
468.
K. von Holt U. Idschok V. Blobel D. Gall H. Fesefeldt P. Freund D. Lüers W. Schrankel B.M. Schwarzschild 《Nuclear Physics B》1976,103(2):221-233
Results on higher moments of the pion multiplicity distribution are presented for pp interactions at 12 and 24 GeV/c incident lab momentum. A simple parametrization for the pion multiplicity distribution is established at 12 and 24 GeV/c and is then used to discuss the energy dependence of higher moments in a range from 4 to about 500 GeV/c incident lab momentum. 相似文献
469.
470.
U. Idschok R. Rödel B. Schröder K. Von Holt V. Blobel H. Fesefeldt W.M. Geist 《Nuclear Physics B》1978,140(3):365-388
Data from a high-statistics bubble chamber experiment at 24 GeV/c are used to study the double diffraction dissociation reaction pp→(pπ+π?) (pπ+π?) where both protons of the initial state dissociate into pπ+π? systems. Cross section, mass spectra and dσ/dt' distributions have been determined and are compared with the results found for the single diffraction dissociation reaction pp → p(pπ+π?), which have been obtained from the same experiment. All our findings agree well with what is expected from the factorization hypothesis. 相似文献