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991.
992.
We derive explicit equations for the maximal function fields F over 𝔽 q 2n given by F = 𝔽 q 2n (X, Y) with the relation A(Y) = f(X), where A(Y) and f(X) are polynomials with coefficients in the finite field 𝔽 q 2n , and where A(Y) is q-additive and deg(f) = q n  + 1. We prove in particular that such maximal function fields F are Galois subfields of the Hermitian function field H over 𝔽 q 2n (i.e., the extension H/F is Galois).  相似文献   
993.
A canonical variable coefficient nonlinear Schrödinger equation with a four-dimensional symmetry group containing SL(2,??) group as a subgroup is considered. This typical invariance is then used to transform by a symmetry transformation a known solution that can be derived by truncating its Painlevé expansion and study blow-ups of these solutions in the L p -norm for p?>?2, L -norm and in the sense of distributions.  相似文献   
994.
In this article, using Darbo's fixed-point theorem associated with the measure of noncompactness, we prove a theorem on the existence of the solutions of some nonlinear functional integral equations in the space of continuous functions on interval [0, a]. Our existence results include several existence results obtained earlier by Maleknejad et al. [7 K. Maleknejad , K. Nouri , and R. Mollapourasl ( 2009 ). Investigation on the existence of solutions for some nonlinear functional-integral equations . Nonlinear Anal. 71 : 15751578 .[Crossref], [Web of Science ®] [Google Scholar]] and Özdemir et al. [8 ?. Özdemir , Ü. Çakan , and B. ?lhan ( 2013 ). On the existence of the solutions for some nonlinear Volterra integral equations . Abstr. Appl. Anal. Article ID 689234.  [Google Scholar]] as special cases under some weaker conditions. We give also some examples which show that our results are applicable.  相似文献   
995.
In this work, we develop a theory of thermoelectric transport properties in two-dimensional semiconducting quantum well structures. Calculations are performed for n-type 0.1 wt.% CuBr-doped Bi2Se3/Bi2Te3/Bi2Se3 and p-type 3 wt.% Te-doped Sb2Te3/Bi2Te3/Sb2Te3 quantum well systems in the temperature range 50–600 K. It is found that reducing the well thickness has a pronounced effect on enhancing the thermoelectric figure of merit (ZT). For the n-type Bi2Se3/Bi2Te3/Bi2Se3 with 7 nm well width, the maximum value of ZT is estimated to be 0.97 at 350 K and for the p-type Sb2Te3/Bi2Te3/Sb2Te3 with well width 10 nm the highest value of the ZT is found to be 1.945 at 440 K. An explanation is provided for the resulting higher ZT value of the p-type system compared to the n-type system.  相似文献   
996.
Anhand der Äquivalenz zwischen der Kaliummenge und der entsprechenden Zählrate (40K) werden Beziehungen angegeben, die es ermöglichen, die Kaliummenge zu bestimmen, deren radiometrischer Einfluβ bei verschiedenen Gesamieffektivitäten vernachlässigbar ist. Für die häufigsten Fälle von Gesamtaktivitätsmessungen von Spaltproduktgemischen mit Hilfe der β-Strahlung sind die radiometrisch vernachlässigbaren Kaliummengen für einige Nahrungsmittel angeührt.  相似文献   
997.
Infrared and Raman spectra of seven new metal (II) 3,4-lutidine tetracyanonickelate complexes, M(3,4 L)2 Ni(CN)4 [where 3,4 L = 3,4 - dimethyl-pyridine or 3,4-lutidine; M = Mn, Fe, Co, Zn, Ni, Cu or Cd] (abbreviated to M - Ni - 3,4 L) have been investigated. Spectroscopic and magnetic susceptibility measurements indicate that the compounds have the structure of Hofmann-type complexes. The copper complex has spectral features different from the other compounds.  相似文献   
998.
Abstract

Secondary metabolites are important components in terms of nutrition and health. Carotenoids and tocopherols, two groups of the fat-soluble components, are also included in this category. There is an increasing interest in the detection of secondary metabolites with near-infrared spectroscopy. However, the number of scientific studies for the detection of these components, especially for tocopherols in corn flour or oil samples by near-infrared reflectance spectroscopy is rather limited. This study was carried out to determine the amount of carotenoids and tocopherols in flour and oil samples of 250 different maize genotypes by near-infrared reflectance spectroscopy using the partial least squares regression modeling method. Liquid chromatography mass spectrophotometry was used as a reference method in order to determine the contents of five carotenoids and four tocopherol subcomponents. The estimation models were created by using the spectral data collected from ground samples, and oil samples extracted from the same flour; along with the results of the reference analysis. The reliability of these models was tested by external validation (n?=?50). The prediction models generated by the spectra taken from corn flour yielded more successful results than the models created with the spectra taken from the oil samples. Among the models compared, the one developed with the spectra taken from flour samples for lutein was the most successful. It is seen that the estimation models generated from flour samples can be used for screening purposes, though different approaches are needed to increase the success of models.  相似文献   
999.
The title compounds platyphylline (C18H29NO5.0.5H2O) and integerrimine (C18H25NO6) have been isolated from the serial parts of the Senecio species. the crystal and molecular structures of platyphylline have been determined. the compound crystallises in orthorhombic space group, P212121. the pyrrolizidine nucleus exhibits exo-buckling conformation. the molecular geometry was stabilized by C-H[ddot]O and C-H[ddot]N hydrogen bonds. a search for the low energy conformations of integerrimine as a similar alkaloid was also carried out. Force field calculations were undertaken by the MM3 program and some particular conformations were computed with the semi-emprical molecular orbital methods by the AMI and PM3 programs.  相似文献   
1000.
An effective solvent model with an explicit solvent representation is described. The modelled perturbation of the solute due to the discrete solvent molecules includes polarization and a non-electrostatic interaction. The latter depends on the overlap between the solute wave function and the solvent orbitals and approximately accounts for the restraint the Pauli principle puts on the space which the solute wave function is allowed to occupy, and consequently also models the exchange repulsion between solute and solvent. The wave function of the solute is a linear combination with variational coefficients of orthogonal states obtained with the complete active space state interaction (CASSI) method. With this model, the solvent shift to the nπ* transition in hydrated formaldehyde is studied and the analysis of the results investigates the different contributions to the total shift; the non-electrostatic interaction is found to be of significance and capable of coupling with the electrostatic interaction in qualitatively different ways for the ground and first excited state. Solvent density distributions for hydrated formaldehyde are also reported.  相似文献   
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