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991.
D. B. Blaschke A. V. Prozorkevich A. V. Reichel S. A. Smolyansky 《Physics of Atomic Nuclei》2005,68(6):1046-1053
In the simple model of massive vector field in a flat spacetime, we derive the kinetic equation of non-Markovian type describing the vacuum pair creation under action of external fields of different nature. We use for this aim the nonperturbative methods of kinetic theory in combination with a new element when the transition of the instantaneous quasiparticle representation is realized within the oscillator (holomorphic) representation. We study in detail the process of vacuum creation of vector bosons generated by a time-dependent boson mass in accordance with the framework of a conformal-invariant scalar-tensor gravitational theory and its cosmological application. It is indicated that the choice of the equation of state allows one to obtain a number density of vector bosons that is sufficient to explain the observed number density of photons in the cosmic microwave background radiation. 相似文献
992.
Monatshefte für Chemie - Chemical Monthly - 相似文献
993.
For many clinical purposes various artificial devices are applied, which contact human tissue and can thus cause adverse reactions between prosthetic surfaces and body components. Of the many materials applied for orthopaedic joint replacements the most common are cobalt-chromium-molybdenum alloys. In these cases considerable amounts of cobalt-chromium-molybdenum wear particles are released from the prostheses which have to be regarded as a cause of long-time problems for the patient.Since these particles are dissolved in body fluids of the surrounding area they are distributed in the whole body via blood. Elevated metal concentrations have been found in blood and urine of persons with endoprostheses. Partly the metals are excreted via urine, but to some extend they accumulate in different organs.Therefore this study dealt with the development of an analytical method for the determination of seven relevant trace elements, namely Al, Co, Cr, Mo, Nb, Ni, and Ti in nine kinds of human tissue (brain, heart, kidney, liver, lung, muscle, lymphatic nodes, spleen, body fat) starting with drawing of the sample, sample work up and finally analysis by means of atomic spectrometry. The optimized method was then applied to determine the metal contents in organs of persons (post mortem) with total hip replacements with metal on metal bearing surfaces. Comparison of the data obtained with those of persons without hip-endoprostheses shows that brain and lung are the main targets for elemental accumulation in persons with hip-endoprostheses. Mo and Nb represent the elements with the highest tendency to be accumulated. 相似文献
994.
Wolfgang Ostwald 《Colloid and polymer science》1907,2(1):13
Ohne Zusammenfassung 相似文献
995.
Zeitschrift für Physik A Hadrons and nuclei - Aus der experimentell gefundenen Verschiebung und dem Aufspaltungsbild von Multiplett-Termen im elektrischen Feld wird die Oszillatorenstärke... 相似文献
996.
Wolfgang Pauli 《Colloid and polymer science》1906,1(4):101-107
Ohne ZusammenfassungNach einem Vortrage in der naturwissenschaftlichen Hauptsitzung der 78. Versammlung deutscher Naturforscher und Aerzte in Stuttgart am 20. September 1906 相似文献
997.
Wolfgang Krull 《Mathematische Annalen》1929,101(1):729-744
Ohne Zusammenfassung 相似文献
998.
Fritz Colonius Wolfgang Kliemann 《Transactions of the American Mathematical Society》2008,360(11):5667-5682
This paper proposes a topological framework for the analysis of the time shift on behaviors. It is shown that controllability is not a property of the time shift, while chain controllability is. This also leads to a global decomposition of behaviors.
999.
The 1,6,7,12,13,18‐hexaazatrinaphthylene (HATN) complex [(Et2Zn)3(μ3‐HATN)] was synthesized and characterized by IR spectroscopy, UV/Vis spectroscopy, elemental analysis and ESI‐MS spectrometry. Attempts to prepare ZnCl2 complexes of HATN leads only to the mononuclear [(Cl2Zn)(HATN)] derivative, characterized by X‐ray diffraction, IR‐ and UV/Vis‐spectroscopy as well as ESI‐MS spectrometry. The bright red 2,2′‐bipyridine (bipy) complex [(Et2Zn)(bipy)] ( 1 ) was synthesized and characterized by X‐ray diffraction and NMR spectroscopy. The UV/Vis‐spectra of the HATN‐complexes show absorptions in regions of far longer wavelengths than the corresponding 2,2′‐bipyridine or 1,10‐phenantroline complexes. Consequently the π*‐LUMO of HATN ( 5 ) is lower in energy than the π*‐LUMO of 2,2′‐bipyridine ( 2 ) or 1,10‐phenanthroline (phen). 相似文献
1000.
Wolfgang Ostwald 《Colloid and polymer science》1936,75(1):39-59
Ohne Zusammenfassung 相似文献