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排序方式: 共有48条查询结果,搜索用时 15 毫秒
1.
In this paper we construct a primitive, non-symmetric 3-class association scheme with parameters v = 36, v1 = 7, p111 = 0 and p211 = 4 and show that such a scheme is determined by its parameters. 相似文献
2.
3.
J. Nassar J. Goldbach 《International journal of environmental analytical chemistry》2013,93(2):145-159
Abstract The problem of determining the concentration changes of reactive hydrocarbon immissions as a function of time was solved by means of an automatic gas chromatograph which, without enrichment, could record ethylene and acetylene in ppb concentrations. At the same time various other pollutants were covered, so that by a mutual allocation of the individual components it was possible to identify certain emitter groups. The results clearly show that ethylene and acetylene primarily originate from the combustion processes of the automobiles, while the handling and storage of petroleum products and their processing do not exert any influence on the immission of the two components. By way of time series measurements during a summer week in 1976 with very intensive solar radiation it was possible to show indirect secondary photochemical reactions. 相似文献
4.
In this paper we extend the plane blow-up results of Grundy& McLaughlin (1997) to the three-dimensional Navier-Stokes equations.Using a solution structure originally due to Lin we first providenumerical evidence for the existence of blow-up solutions on- < x, z < , 0 y 1 with boundary conditions on y = 0and y = 1 involving derivatives of the velocity components.The formulation enables us to consider plane and radial flowas special cases. Various features of the computations are isolatedand are used to construct a formal asymptotic solution closeto blow-up. We show that the numerical and asymptotic analysesprovide a mutually consistent global picture which supportsthe conclusion that, for the family of problems we considerhere, blow-up in fact can take place in three dimensions butat an inverse linear rate rather than the faster inverse squareof the plane case. 相似文献
5.
Ice nucleating-active Pseudomonas fluorescens F264C was fed to Colorado potato beetles to determine bacterial retentioin in the beetle gut and its effect on the cold hardiness of this insect pest. The bacrterium was present in beetles recovered after overwintering in the field, seven months after their exposure to P. fluorescens. Retention was evident not only in the detection of the P. fluorescens ice nucleating gene, inaW, in bacterial cultures from beetle guts but also in the elevated supercooling points of some treated beetles. 相似文献
6.
K. Goldbach und K. H. Lieser 《Fresenius' Journal of Analytical Chemistry》1982,311(3):183-186
Zusammenfassung Die Abtrennung von Spurenelementen (Hg, Cd, As, Mo, Cr) an drei Celluloseaustauschern mit chelatbildenden Ankergruppen wird beschrieben. An den Austauschern mit den Ankergruppen o-Aminothiophenol und Glyoxal-bis(2-mercaptoanil) werden hohe Verteilungskoeffizienten für Hg2+, Hg
2
2+
, CH3Hg+ und Cd2+ gefunden, niedrigere für Arsenit und Arsenat; (CH3)2Hg wird nicht gebunden. Der mit Fe3+ beladene Hyphan-Austauscher weist hohe Verteilungskoeffizienten für Arsenat auf, etwas niedrigere für Arsenit, Chromat und Molybdat. In Trennsäulen werden die Kationen Hg2+ und Cd2+ und die Anionen Arsenat und Molybdat voneinander getrennt.
Herrn Prof. Dr. H. Weisz zum 60. Geburtstag gewidmet 相似文献
Separation of toxic heavy metals from solutions by means of chelating cellulose exchanges
Summary The separation of trace elements (Hg, Cd, As, Mo, Cr) on three cellulose exchangers with chelating anchor groups is described. On exchangers with the anchor groups o-aminothiophenol and glyoxal-bis(2-mercaptoanil) high distribution coefficients are found for Hg2+, Hg 2 2+ , CH3Hg+ and Cd2+, lower ones for arsenite and arsenate; (CH3)2Hg is not bound. The exchanger Hyphan loaded with Fe3+ shows high distribution coefficients for arsenate, somewhat lower ones for arsenite, chromate and molybdate. In separation columns the cations Hg2+ and Cd2+ and the anions arsenate and molybdate are separated from each other.
Herrn Prof. Dr. H. Weisz zum 60. Geburtstag gewidmet 相似文献
7.
A. Benoit M. Chapellier G. Chardin L. Dumoulin K. Eitel J. Gascon G. Gerbier C. Goldbach J. Jochum A. de Lesquen G. Nollez F. Pröbst W. Seidel 《Physics letters. [Part B]》2006
The ZEPLIN Collaboration has recently published its first result presenting a maximum sensitivity of 1.1×10−6 picobarn for a WIMP mass of ≈60 GeV. The analysis is based on a discrimination method using the different time distribution of scintillation light generated in electron recoil and nuclear recoil interactions. We show that the methodology followed both for the calibration of the ZEPLIN-I detector response and for the estimation of the discrimination power is not reliable enough to claim any background discrimination at the present stage. The ZEPLIN-I sensitivity appears then to be in the order of 10−3 picobarn, three orders of magnitude above the claimed 1.1×10−6 picobarn. 相似文献
8.
HARUN REŞIT YAZAR 《Pramana》2013,81(4):579-585
The sd-interacting boson approximation (sd-IBA) and the df-interacting boson approximation (df-IBA) can be related to each other and the states of the interacting boson approximation model can be identified with the fully symmetric states in the sdf interacting boson approximation model. A systematic study of the sdf-IBA model showed that the constructed Hamiltonian can successfully describe the strong octupole correlations in the deformed nuclei. We showed that the interacting boson approximation may account for many of these K π ?=?0+ states. It was found that the calculated energy spectra of the gadolinium isotopes agree quite well with the experimental data. The observed B(E2) values were also calculated and compared with the experimental data. 相似文献
9.
H 2 permeation hysteresis has been observed during cycling of a 3 mum thick supported PdCu membrane with approximately 50 atom % Pd through the fcc/bcc (face-centered cubic/body-centered cubic) miscibility gap between 723 and 873 K. Structural investigations after annealing of membrane fragments under H 2 at 823 K reveal retardation of the fcc(H) --> bcc(H) transition, which is attributed to the occurrence of metastable hydrogenated fcc PdCu(H) phases. The H(2) flux at 0.1 MPa H(2) pressure difference in the well-annealed bcc single phase regime below 723 K can be described by J(H2) = (1.3 +/- 0.2) mol.m (-2).s (-1) exp[(-11.1 +/- 0.6) kJ.mol (-1)/( RT)] and that in the fcc single phase regime above 873 K by J(H2) = (7 +/- 2) mol.m (-2).s (-1) exp[(-30.3 +/- 2.5) kJ.mol (-1)/( RT)]. 相似文献
10.
R. Goldbach 《Applied Mathematics and Optimization》1999,39(1):121-142
We adapt some randomized algorithms of Clarkson [3] for linear programming to the framework of so-called LP-type problems,
which was introduced by Sharir and Welzl [10]. This framework is quite general and allows a unified and elegant presentation
and analysis. We also show that LP-type problems include minimization of a convex quadratic function subject to convex quadratic
constraints as a special case, for which the algorithms can be implemented efficiently, if only linear constraints are present.
We show that the expected running times depend only linearly on the number of constraints, and illustrate this by some numerical
results. Even though the framework of LP-type problems may appear rather abstract at first, application of the methods considered
in this paper to a given problem of that type is easy and efficient. Moreover, our proofs are in fact rather simple, since
many technical details of more explicit problem representations are handled in a uniform manner by our approach. In particular,
we do not assume boundedness of the feasible set as required in related methods.
Accepted 7 May 1997 相似文献