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51.
Daniel Krois Mario Simonetti Erich Wünsch 《Monatshefte für Chemie / Chemical Monthly》1989,120(11):1029-1041
Summary For the identification of a protein predicted by DNA sequence analysis of the TTV1 virus from the archaebacteriumThermoproteus tenax, the trieicosapeptide H-Thr-Pro-Thr-Pro-Thr-Pro-Thr-Tyr-Asp-Ile-Thr-Tyr-Val-Val-Phe-Asp-Val-Thr-Pro-Ser-Pro-Thr-Pro-OH, corresponding to the protein fragment 79–101, was prepared by conventional methods of peptide synthesis. This sequence portion may possibly represent a suitable protein specific immunepitope.
Zur Hypothese eines TTV1 Virus/Thermoproteus tenax F154-Proteins. Teil II: Synthese des Protein-fragments 79–101
Zusammenfassung Für den Nachweis der Expression des Proteins F154 — nach einer Sequenzanalyse des Genoms des TTV1 Virus im ArchaebakteriumThermoproteus tenax postuliert — wurde das Peptid H-Thr-Pro-Thr-Pro-Thr-Pro-Thr-Tyr-Asp-Ile-Thr-Tyr-Val-Val-Phe-Asp-Val-Thr-Pro-Ser-Pro-Thr-Pro-OH (Proteinfragment 79–101) mit Hilfe konventioneller Peptidsynthese hergestellt. Diese Peptidsequenz sollte ein geeignetes proteinspezifisches Immunepitop darstellen.相似文献
52.
53.
Jinsong Zhang Chris Taylor Erich Bowman Leo Savage-Low Michael W. Lodewyk Larry Hanne Guang Wu 《Tetrahedron letters》2013
A process for synthesizing 1,4-benzodioxin, through oxidation of a phenol to an o-quinone followed by treatment with an enamine, has been developed. Adduct stereochemistry is found to be retained via this one-pot reaction. The method uses hypervalent iodine reagent under mild conditions and is compatible with a wide scope of phenols and enamines. 相似文献
54.
A magnetic balance was used for measuring the susceptibility of metals and alloys, in an atmosphere of purified argon, up to 1800°c. Comparison of the susceptibilities of liquid Fe, Co and Ni gives information on the liquid state. The changes in the susceptibilities of Ge, Sn and Te on melting are typical of semi-metallic elements and semiconductors, but their behaviour differs according to the degree of symmetry in the solid state. 相似文献
55.
Coupled Hartree-Fock theory is used to compute and map the current density induced in planar hydrocarbons by an external magnetic field. Results of useful accuracy can be obtained with modest (6-31G**) basis sets by employing a continuous gauge transformation. Maps are presented and discussed for benzene, naphthalene, anthracene, tetracene, pentacene, heptacene, and biphenylene. © 1996 John Wiley & Sons, Inc. 相似文献
56.
The anionic polymerization of butadiene, to both the 1,2- and 1,4-addition products, is an important industrial process. It is known that the reaction can be steered to either the 1,2- or 1,4-product by the addition, or absence, of a complexing solvent such as ether. The goals of the current study were to map the MNDO Potential Energy Surfaces (PES) of the propagation reactions both in the presence and absence of dimethyl ether to gain insight into the factors influencing the reaction's selectivity. Single point ab initio calculations at the DZP level were run on all reactants, products and transition states as a cross check on the MNDO results. 相似文献
57.
Erich Zobetz 《Crystal Research and Technology》1994,29(3):379-385
A new theorem on homometric polytypes is presented. Examples of homometric close-packed structures and MX2-polytypes are given. The method derived may be used to construct homometric n-tuplets by means of decomposition procedures. 相似文献
58.
Erich R. Bagge 《Fortschritte der Physik》1994,42(1):95-100
At a summary of the four present measurements for the solar neutrino problem one receives for the quotient of the number of the really observed events and the theoretically by the standard solar model exspected value the result This says that in the mean only 33.25% with a possible mistake of 19.25% of the exspected solar neutrinos have been observed. If one goes out from the assumption, that the attempts hitherto proposed for the solution of the problem on the solar neutrino deficits as to be regarded as very unsatisfactory on the one side, while on the other the neutrinos of the β-decay may not exist at all, this looks very troublesome. But there is another possibility of a new interpretation. One has to consider, that in connection with each theoretically until now assumed neutrino of β-decay at the solar p-p- and all joined following fusion -processes precisely one positron will be produced. Exactly this particle will with the probability 1/2 in a triplett state of fixing with an electron of the solar centre plasma at a binding energy of −2029.7 eV create an electric-neutral duotron. This particle assumes fully, inclusive the very welcome factor 1/2, the rǒle of the theoretically dispensable neutrino. This can be regarded as the solution of the solar neutrino-problem. 相似文献
59.
Functional load (FL) quantifies the contributions by phonological contrasts to distinctions made across the lexicon. Previous research has linked particularly low values of FL to sound change. Here, we broaden the scope of enquiry into FL to its evolution at higher values also. We apply phylogenetic methods to examine the diachronic evolution of FL across 90 languages of the Pama–Nyungan (PN) family of Australia. We find a high degree of phylogenetic signal in FL, indicating that FL values covary closely with genealogical structure across the family. Though phylogenetic signals have been reported for phonological structures, such as phonotactics, their detection in measures of phonological function is novel. We also find a significant, negative correlation between the FL of vowel length and of the following consonant—that is, a time-depth historical trade-off dynamic, which we relate to known allophony in modern PN languages and compensatory sound changes in their past. The findings reveal a historical dynamic, similar to transphonologization, which we characterize as a flow of contrastiveness between subsystems of the phonology. Recurring across a language family that spans a whole continent and many millennia of time depth, our findings provide one of the most compelling examples yet of Sapir’s ‘drift’ hypothesis of non-accidental parallel development in historically related languages. 相似文献
60.
P. Staszczuk D. Sternik G. W. Chądzyński E. Robens M. Błachnio 《Journal of Thermal Analysis and Calorimetry》2006,86(1):133-136
Nitrogen
adsorption measured at 77 K was used to characterize the surface heterogeneity
of high-temperature superconductor surfaces. Properties relating to adsorption
and porosity of the solids (adsorption capacity, specific surface area, radii
and volume of the pores, pore-size distribution function) were determined
from nitrogen adsorption–desorption isotherms and atomic force microscopy
(AFM) for a series of oxide superconductors. It is shown that the adsorption
isotherms of all samples are S-shaped and belong to type II according to the
IUPAC classification. On the basis of the nitrogen adsorption isotherms and
AFM data, fractal dimensions were determined and correlations found with adsorption
and porosity parameters. 相似文献