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991.
Analysis of the globins from fast human haemoglobins by isoelectrofocusing on polyacrylamide gel rods 总被引:2,自引:0,他引:2
M Castagnola P Caradonna L Cassiano C Degen F Lorenzin D Rossetti M L Salvi 《Journal of chromatography. A》1984,307(1):91-102
The globins from all fast haemoglobin (Hb) components obtainable by Bio-Rex 70 cation-exchange chromatography were examined by isoelectrofocusing on polyacrylamide gel rods with 8.0 mol/l urea. From this analysis HbA1a1 and HbA1a2 seem to be very heterogeneous components. HbA1b is separable into two components, one of which is varied in both the beta chains. Between HbA1b2 and the well-known HbA1c components two chromatographic peaks are separated, one with a noticeable percentage of glucosylated beta chain and one that probably contains HbF. HbA1c has both beta chains glucosylated, while HbA1x seems to be a beta monoglucosylated Hb form. Finally, the early part of the HbAo peak has a large amount of glucosylation on both alpha and beta chains. 相似文献
992.
993.
994.
Under the combined influence of applied shear and electric fields, the macroscopic behavior of suspensions reflects coupling of the two fields which produces stresses at the phase boundaries. These stresses in turn cause motion and/or deformation of the suspended phase. Electrohydrodynamic (EHD) factors which govern these motions and deformations are reviewed in detail. both in a general theoretical context and also in terms of extensive experimental observations. Throughout an attempt has been made to relate the microscopic behaviour (including interactions) of the suspended phase to macroscopically observable or bulk properties of the suspension as a whole.The phenomena reviewed here are important to a large number of colloidal problems of interest to the physical, biological and earth sciences. 相似文献
995.
Allylsilanes show in certain cases a behaviour towards electrophiles which is opposite to that of its carbon homologues. Theoretical calculations using Dewar's MINDO/3 method performed on 3-methyl 3-butenyl trimethylsilane and 2-methyl 2-butene show that geometrical optimization leads to a silicon-allylic carbon bond nearly parallel to the double bond π cloud, and both net atomic charges and HOMO coefficients indicate an inversion between these two substrates. 相似文献
996.
Individual state-to-state rotational transitions have been resolved in small angle scattering of polarized CsF molecules on Ne, Ar, C2, H6, N2, CO, CO2, CHF3 at center of mass energies of about 0.1 eV. The absolute inelastic cross sections range from 5Å2 up to 600Å2. 相似文献
997.
Various techniques (thermal analysis, dilatometry, X-ray diffraction, nuclear magnetic resonance, mass spectrometry, electrical measurements) have been used to study the thermal behaviour of several “half-aromatic” polyamides and polysulphonamides. Three transition phenomena were revealed and related to morphological modification of polymers. 相似文献
998.
Gamma-butyrolactone (GBL) was shown to decompose on the clean surface of Li, Na, K, and their amalgams. Polarization curves were obtained on Pt and “Kovar” electrodes at potentials from 4 to ?4 V vs. Li?Hg in 0.5 M LiClO4 or vs. K?Hg in 0.5 M KPF6. GBL was found to reduce electrochemically at potentials more positive than 1 V. Various passivation phenomena provoked by the decomposition of the solvent were observed, hindering cathodic deposition of the alkali metals from solutions of their salts in GBL. The presence of a high-molecular surfactant in the electrolyte suppresses the decomposition of GBL and suggests a path to the deposition of Li on the electrode. 相似文献
999.
P. Caillet 《Journal of organometallic chemistry》1975,102(4):481-490
A valence force field of methyl benzoate tricarbonylchromium is determined from the force field of methyl benzoate and that of hexacarbonylchromium. The results show the perturbation made both to the aromatic ring and to the carbonyl bonds by the chromiumring bond. This work is the first complete analysis of the vibrational spectra of methyl benzoate tricarbonylchromium. 相似文献
1000.
The number of products and the H2/CH4 ratio obtained from the flow pyrolyses of (CH3)3GeH and (CH3)3SiH were very different. The (CH3)3GeH decomposition is consistent with the following mechanism:
The pyrolysis of (CH3)3SiH was found to be much more complex, presumably due to the formation of silicon-carbon double bonded intermediates and the (CH3)2Si(H)CH2 radical. We also present data which supports the presence of a H atom chain sequence during this pyrolysis. 相似文献
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