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71.
The structure and hydration of insulin-like growth factor 1 and an inactive mutant lacking the C region have been investigated in aqueous solution by molecular dynamics simulation. The overall structures of the two polypeptide resemble those determined by NMR spectroscopy. The deletion of the C region in the wild polypeptide introduces structural stability in the mutant, leading to a better definition of the secondary structure elements. A detailed hydration analysis was performed using the radial distribution functions and energy distributions. The backbone of the mutant is in general more solvent accessible than the wild polypeptide backbone. The structural rearrangements induced in the mutant led to changes in the solvent exposition of Tyr24 and Tyr60, which are residues important for ligand—receptor complex formation. Tyr24 exhibited a similar degree of solvent exposition in both IGF-I and in the mutant; however, its hydroxyl group in the wild polypeptide is better solvated than in the mutant. Tyr60 was found to be solvent exposed in the wild protein, while in the mutant the involvement of its hydroxyl group in intramolecular hydrogen bonds led to it being buried away from the solvent. 相似文献
72.
73.
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75.
F. Henrich 《Fresenius' Journal of Analytical Chemistry》1905,44(11):702-703
Ohne Zusammenfassung 相似文献
76.
Edmund Henrich Klaus H. Ebert 《Angewandte Chemie (International ed. in English)》1992,31(10):1283-1297
In the GALLium Experiment, GALLEX, low-energy solar neutrinos produced in the main hydrogen fusion reaction inside the Sun are being counted for the first time in a radiochemical gallium detector. In this way, the theories about stellar structure may be verified and the question of the existence of a neutrino rest mass be brought closer to a solution. The experiment is being carried out with international collaboration at the Gran Sasso underground laboratory (LNGS) in the Abruzzi mountains in Italy. In this paper we survey the planning, construction and initial experimental operation of the gallium detector, paying special attention to the chemical aspects of the experiment. The chemical problem to be solved is the separation of very few 71Ge atoms from 100 metric tons of a highly concentrated GaCl3 solution acidified with hydrochloric acid. In addition, these Ge atoms must be isolated and converted into germane, GeH4, for low-level counting of 71Ge in a gas proportional counter. After extensive preparatory work to meet the extreme requirements of the experiment, the first results have now become available. 相似文献
77.
D. Krennrich R. Knappe B. Henrich R. Wallenstein J.A. L’huillier 《Applied physics. B, Lasers and optics》2008,92(2):165-174
This paper reports on efficient generation of cw laser radiation at 0.9 and 1.3 μm in different neodymium doped laser hosts.
The thermal, mechanical and optical properties as well as the laser performance of Nd:YAG, Nd:YAlO3, Nd:YVO4 and Nd:GdVO4 are studied in numerical simulations as well as in experimental investigations. For example an output power of more than
4.0 W is generated in Nd:YVO4 at the 914 nm 4F3/2→4I9/2 transition using a pump power of 19 W. In Nd:GdVO4 more than 6.0 W are obtained at the 1342 nm 4F3/2→4I13/2 laser transition by using a pump power of 19.3 W. The spatial beam quality of both lasers is diffraction limited with an
M2 value of less than 1.1.
PACS 42.70.Hj; 42.55.Xi; 42.60.Pk 相似文献
78.
D. Krennrich R. Knappe B. Henrich R. Wallenstein J.A. L’huillier 《Applied physics. B, Lasers and optics》2008,92(2):175-183
This paper reports on the generation of picosecond (ps) laser pulses by self-phase-adjusting additive-pulse-mode-locking (PSA)
at wavelengths of 0.9 and 1.3 μm. The main objective of this work was to investigate and compare the characteristic optical
properties of ps lasers based on different Nd-doped laser crystals like Nd:YAG, Nd:YAlO3, Nd:YVO4 and Nd:GdVO4. As a result of these investigations a mode-locked Nd:YVO4 laser for example, generated, ps pulses at 1.3 μm with a duration of 7 ps, a repetition rate of 160 MHz and an average power
of 4.7 W. At 0.9 μm pulses with a duration of 1.9 ps were obtained at a repetition rate of 158 MHz and an average power of
2.8 W.
PACS 42.70.Hj; 42.65.Re; 42.65.Ky 相似文献
79.
A. Henrich P. Hoffmann H. M. Ortner T. Greve H. Itzel 《Analytical and bioanalytical chemistry》2000,368(2-3):130-138
Chemicals from customers’ returns have to be analyzed before they can be reused as raw materials in production. A procedure for non-invasive qualitative analysis of compounds in a closed container based on energy dispersive X-ray fluorescence (EDXRF) spectrometry is described. EDXRF was chosen as method for non-invasive analysis of chemicals through PE bottle walls without opening the bottle. This analysis aims for a quick proof of correspondence between the declaration of a reagent on the label of the bottle and its content. This analytical result cannot be achieved by a mere evaluation of characteristic element lines in EDXRF-spectra in combination with the method of matrix correction or the method of mean atomic number. These methods take into account only a small part of the total information available in an X-ray spectrum. It is shown here that valuable additional information is extractable from the spectral ranges of the Compton-scattering and Rayleigh-scattering areas by the use of methods of multivariate data analysis, especially by principle component analysis (PCA). Regularized discriminant analysis (RDA) was employed to establish a classification scheme for unknown samples. 相似文献
80.
H. Henning Winter Miriam Siebenbürger David Hajnal Oliver Henrich Matthias Fuchs Matthias Ballauff 《Rheologica Acta》2009,48(7):747-753
Concentrated, non-crystallizing colloidal suspensions in their approach of the glass state exhibit distinct dynamics patterns.
These patterns suggest a powerlaw rheological constitutive model for near-glass viscoelasticity, as presented here. The rheological
parameters used for this model originate in the mode-coupling theory. The proposed constitutive model provides explicit expressions
for the steady shear viscosity, the steady normal stress coefficient, the modulus-compliance relation, and the α peak of G″. The relaxation pattern distinctly differs from gelation. 相似文献