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231.
Branko Vukovi? Dario Faj Vanja Radoli? & Josip Planini? 《Isotopes in environmental and health studies》2013,49(2):169-176
Lung-cancer risk to the general population from indoor radon remains controversial, although studies of radon exposure have established that radon decay products have been a cause of lung cancer among miners. For the case group of patients, suffering from lung cancer, and the control group distributions of the number of homes with high indoor levels of radon were compared with the log-normal distribution, the empirical frequency distribution of the control group obeyed the theoretical log-normal distribution. Using the ratio of frequencies of the case group to the control groups, or the relative frequencies, an association between the relative frequencies and indoor radon concentrations was found, and a positive correlation coefficient was obtained, thus enabling the rate of lung cancer to be estimated for certain indoor radon concentrations. The significant difference between the mean radon levels for the case sample and the control led to the conclusion that patients with lung cancer lived in homes with radon concentrations which were significantly higher than those of Osijek’s inhabitants for the control sample. 相似文献
232.
Jure Bezenšek Benjamin Prek Uroš Grošelj Marta Kasunič Jurij Svete Branko Stanovnik 《Tetrahedron》2012,68(24):4719-4731
Herein a simple, metal-free synthesis of 2-alkyl-, 2-cycloalkyl-, 2-aryl-, and 2-heteroaryl-substituted pyridine 3,4-dicarboxylates and their N-oxides from the corresponding methyl ketones in good to excellent yield, demonstrated with 22 examples in each case, is described. The method complements the current coupling reactions of 2-heterocyclic organometallic reagents. 相似文献
233.
We study a supersymmetric model in curved background spacetime. We calculate the effective action and the vacuum expectation value of the energy momentum tensor using a covariant regularization procedure. A soft supersymmetry breaking induces a nonzero contribution to the vacuum energy density and pressure. Assuming the presence of a cosmic fluid in addition to the vacuum fluctuations of the supersymmetric field an effective equation of state is derived in a self-consistent approach at one loop order. The net effect of the vacuum fluctuations of the supersymmetric fields in the leading adiabatic order is a renormalization of the Newton and cosmological constants. 相似文献
234.
Heinz Langer Branko Najman Christiane Tretter 《Communications in Mathematical Physics》2006,267(1):159-180
In this paper we investigate an abstract Klein–Gordon equation by means of indefinite inner product methods. We show that, under certain assumptions on the potential which are more general than in previous works, the corresponding linear operator A is self-adjoint in the Pontryagin space induced by the so-called energy inner product. The operator A possesses a spectral function with critical points, the essential spectrum of A is real with a gap around 0, and the non-real spectrum consists of at most finitely many pairs of complex conjugate eigenvalues of finite algebraic multiplicity; the number of these pairs is related to the ‘size’ of the potential. Moreover, A generates a group of bounded unitary operators in the Pontryagin space . Finally, the conditions on the potential required in the paper are illustrated for the Klein–Gordon equation in ; they include potentials consisting of a Coulomb part and an L
p
-part with n ≤ p < ∞.Branko Najman: Deceased 相似文献
235.
Branko Malešević Dragana Todorić Ivana Jovović Sonja Telebaković 《Applied Mathematics Letters》2010,23(11):1367-1371
This paper deals with the reduction of non-homogeneous linear systems of first order operator equations with constant coefficients. An equivalent reduced system, consisting of higher order linear operator equations having only one variable and first order linear operator equations in two variables, is obtained by using the rational canonical form. 相似文献
236.
Branko Grünbaum Tomáš Kaiser Daniel Král’ Moshe Rosenfeld 《Israel Journal of Mathematics》2010,179(1):235-252
A polytope P with 2n vertices is called equipartite if for any partition of its vertex set into two equal-size sets V
1 and V
2, there is an isometry of the polytope P that maps V
1 onto V
2. We prove that an equipartite polytope in ℝ
d
can have at most 2d+2 vertices. We show that this bound is sharp and identify all known equipartite polytopes in ℝ
d
. We conjecture that the list is complete. 相似文献
237.
A flaw in Lemma 2 is corrected and other parts of the paper changed a accordingly so as to preserve all the theorems.
We are indebted to Professor Rigby for kindly bringing these facts to our attention. 相似文献
238.
Branko S. Brčić Danilo Dobčnik Ljubo Golič 《Monatshefte für Chemie / Chemical Monthly》1963,94(6):1145-1153
Zusammenfassung Die Resultate isothermer Messungen der Sorption der Stickoxyde an CaO bei verschiedenen Drücken (0,05 bis 1 Atm) und bei Temperaturen von 20 bis 650°C werden wiedergegeben. Im untersuchten Temperaturintervall verläuft die Reaktion unter Bildung von Calciumnitrat mit kleinen Nitritbeimengungen. In bezug auf die Kinetik der Bildung kann man das untersuchte Temperaturintervall für 1 Atm Stickoxyde-Druck in drei Bereiche einteilen: unter 50°C, von 50 bis 400°C und von 450 bis 610°C. In den ersten zwei Bereichen findet die Reaktion im System fest—gasförmig statt, während im dritten die Gasphase mit einer mehr oder weniger ausgeprägten Schmelze reagiert. 相似文献
239.
A subset of a metric space is called metrically homogeneous if the set of distances from a chosen point of the subset to all
the other points of the subset is independent of the chosen point. The main result of the paper is a complete characterization
of the compact, metrically homogeneous subsets of the Euclidean plane. 相似文献
240.
Rhodium(I)-catalyzed ene-allene carbocyclization strategy for the formation of azepines and oxepines 总被引:1,自引:0,他引:1
[reaction: see text] A novel strategy for the preparation of seven-membered heterocyclic compounds has been realized. Treatment of ene-allene 1 with a catalytic quantity of rhodium biscarbonyl chloride dimer affords the cyclization product 2 in moderate to high yields. The scope and limitations of this new method are currently under investigation, and the results obtained to date are discussed within. 相似文献