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101.
Kett V  McMahon D  Ward K 《Cryo letters》2004,25(6):389-404
This review describes the range of thermal analysis techniques that may be used to investigate the key thermal properties of formulations to be freeze-dried and the resultant products. The use of these allows development of cost-effective processing while maintaining optimum product quality.  相似文献   
102.
103.
Data on the charge-exchange reaction π?p → (π+π?π0)n have been taken at beam momenta of 12 and 15 GeV/c, using the CERN Omega Multiparticle Spectrometer. A partial-wave analysis has been made of the (3π)0 system. We observe both natural and unnatural spin-parity production. The natural parity states can be identified with established resonances. In addition a natural spin-parity enhancement is observed at a mass of about 2 GeV/c2 with JP = 4+ preferred. We have called this effect the A21 (2030). The unnatural spin-parity production found is consistent with reggeized Deck model predictions. No unambiguous A1 or A3 production is observed.  相似文献   
104.
Data on the reaction π?p → π+π?π0 have been taken at 12 and 15 GeV/c with the CERN Omega multiparticle spectrometer. In a 3-pion partial-wave analysis strong production of A20 (1310) and ω1 (1675) is observed. Total and differential cross sections are determined and density matrix elements presented as a function of t in the t- and s-channel frames. The energy dependence of A20 production is studied, and a comparison of ω(780), A20(1310) and ω1 (1675) production is made.  相似文献   
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106.
NMR linewidth studies of molecular motion in several polyacrylonitrile samples have been carried out. The motional transition temperature is found in the 105–124°C. range and depends upon polymerization conditions. In addition, the thermal activation energy for the motional process underlying this transition was evaluated at 16.4 kcal./mole. Finally, measurement of the transition temperature for one of the specimens in three different physical states (bulk, spun only, and spun and drawn with a ratio of 3:1), revealed that no change in the transition temperature was effected by either spinning or drawing.  相似文献   
107.
Wideline NMR techniques have been applied to both singly and doubly oriented specimens of nylon 66. Variations in the spectra obtained are observed for different orientations of the specimens relative to the applied field. These variations demonstrate that the zigzag chain axis is essentially parallel to the draw direction and that motion occurs in all of the sample. The motion is of two types: random in the mobile regions and rotation of segments about the chain axis in the rigid regions.  相似文献   
108.
The reaction π?p → ωn has been studied at 8 and 12 GeV/c incident momenta with the CERN Omega spectrometer using a neutron time of flight trigger. The differential cross sections and the ω-decay density matrix elements are presented as functions of the momentum transfer squared ?t in the range of 0.02 to 0.80 GeV2. The data are used to evaluate the intercept and slope of both the natural and unnatural parity exchange trajectories. Regge exchange amplitude factorisation tests involving the reaction πN → ωN are investigated.  相似文献   
109.
Elastic and charge-exchange K+n differential cross sections have been measured from K+d interactions from 430 to 940 MeV/c using spark chambers and scintillation counters. The data have been compared with existing results and in an accompanying paper have been included with other measurements in a phase-shift analysis.  相似文献   
110.
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