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101.
102.
ONTHEBOUNDEDNESSANDTHESTABILITYRESULTSFORTHESOLUTIONOFCERTAINFOURTHORDERDIFFERENTIALEQUATIONSVIATHEINTRINSICMETHODCemilTUNC;A... 相似文献
103.
104.
This paper addresses the heat treatment operation in a manufacturing plant that produces different types of cylindrical parts. The immediate prior process to heat treatment is furnace-loading, where parts are loaded into baskets. The furnace-loading process is complex and involves issues relating to geometry, and heterogeneity in the parts and in their processing requirements. Currently, furnace-loading is accomplished by operator ingenuity; consequently, the parts loaded in heat treatment often do not use furnace capacity adequately. Efficiency in furnace operation can be achieved by improving basket utilization, which is determined by the furnace-loading process. This paper describes the development of integer and mixed integer LP models for 3D loading of cylindrical parts into furnace baskets. The models consider the exact location of parts to be loaded on the basket and incorporate three models with different objectives; the first addresses the nesting of parts within one another, the second addresses the number of basket layers used, and the third addresses the number of baskets used. 相似文献
105.
Let (M,g) be an n-dimensional Riemannian manifold and T*M be its cotangent bundle equipped with the rescaled Sasaki type metric. In this paper, we firstly study the paraholomorphy property of the rescaled Sasaki type metric by using some compatible paracomplex structures on T*M. Second, we construct locally decomposable Golden Riemannian structures on T*M. Finally we investigate curvature properties of T*M. 相似文献
106.
We have measured electronic and Raman scattering spectra of 1,1',3,3'-tetraethyl-5,5',6,6'-tetrachloro-benzimidazolocarbocyanine iodide (TTBC) in various environments, and we have calculated the ground state geometric and spectroscopic properties of the TTBC cation in the gas and solution phases (e.g., bond distances, bond angles, charge distributions, and Raman vibrational frequencies) using density functional theory. Our structure calculations have shown that the ground state equilibrium structure of a cis-conformer lies ~200 cm(-1) above that of a trans-conformer and both conformers have C(2) symmetry. Calculated electronic transitions indicate that the difference between the first transitions of the two conformers is about 130 cm(-1). Raman spectral assignments of monomeric- and aggregated-TTBC cations have been aided by density functional calculations at the same level of the theory. Vibrational mode analyses of the calculated Raman spectra reveal that the observed Raman bands above 700 cm(-1) are mainly associated with the in-plane deformation of the benzimidazolo moieties, while bands below 700 cm(-1) are associated with out-of-plane deformations of the benzimidazolo moieties. We have also found that for the nonresonance excited experimental Raman spectrum of aggregated-TTBC cation, the Raman bands in the higher-frequency region are enhanced compared with those in the nonresonance spectrum of the monomeric cation. For the experimental Raman spectrum of the aggregate under resonance excitation, however, we find new Raman features below 600 cm(-1), in addition to a significantly enhanced Raman peak at 671 cm(-1) that are associated with out-of-plane distortions. Also, time-dependent density functional theory calculations suggest that the experimentally observed electronic transition at ~515 nm (i.e., 2.41 eV) in the absorption spectrum of the monomeric-TTBC cation predominantly results from the π → π? transition. Calculations are further interpreted as indicating that the observed shoulder in the absorption spectrum of TTBC in methanol at 494 nm (i.e., 2.51 eV) likely results from the ν(") = 0 → ν' = 1 transition and is not due to another electronic transition of the trans-conformer-despite the fact that measured and calculated NMR results (not provided here) support the prospect that the shoulder might be attributable to the 0-0 band of the cis-conformer. 相似文献
107.
Learning to estimate a linear measurement is critical in becoming a successful measurer. Research indicates that the teaching of the estimation of linear measurement is quite open and that instruction does not make explicit to students how to carry out estimation work. Because written curriculum has been identified as one of the main sources affecting teachers’ instruction and students’ learning, this study examined how estimation of linear measurement tasks were presented to students in three US elementary mathematics curricula to see how much and in what ways these tasks were presented in an open manner. The principal result was that the length estimation tasks were frequently not explicit about which attribute of the object to measure and the requested level of precision of the estimate. Length estimation tasks were also left more open than other measurement tasks like measuring length with rulers. 相似文献
108.
In this note, we reply to the comments by Rees and Magyari (2007) on our article (Aydin and Kaya 2007). They mainly stated
that the thermal boundary conditions we defined at the edge of the boundary layer were incompatible with the energy equation.
This is questionable and therefore we will discuss it below. They disclosed that our results were in error. However, this
is quite misleading. Scientifically, they cannot reach such a conclusion without comparing our results with what they thought
to be correct. In fact, this misleading and unproven statement will be shown not to be correct in the following. 相似文献
109.
Aydin Tavman Naz M. Agh-Atabay Abdollah Neshat Fahrettin Gucin Basaran Dulger Durata Haciu 《Transition Metal Chemistry》2006,31(2):194-200
2-(5-H/methyl-1H-benzimidazol-2-yl)-4-bromo/nitro-phenol (HLx:X=1–4) ligands and their iron(III) nitrate complexes have been synthesized and characterized. In all of the complexes, the
ligands are bidentate, via one imine nitrogen atom and a phenolate oxygen atom. The coordination is completed with a bidentate nitrate anion, and a
water molecule. Elemental analysis, molar conductivity, magnetic susceptibility, FT-Raman, FT-IR (mid i.r., far i.r.), UV–visible
and as well as quantum chemical calculations performed with CACHE are in agreement with a 1:1 electrolyte structures that
are mononuclear, and distorted 5-coordinate square pyramidal. The antimicrobial activities of free ligands, their hydrochloride
salts and the complexes were evaluated using the disk diffusion method in dimethyl sulfoxide (DMSO) toward nine bacteria,
each with multiple, fresh clinical isolates, and the results are compared with those for penicillin-g, ampicillin, cefotaxime,
vancomycine, oflaxacin and tetracycline. Antifungal activities were reported for Kluyveromyces fragilis, Rhodotorula rubra, Candida albicans, Hanseniaspora Guilliermondii and Debaryomyces hansenii yeasts, each with multiple isolates, and the results were referenced against nystatin, ketaconazole and clotrimazole antifungal
agents. In most cases, the compounds tested showed broad-spectrum (Gram+ and Gram−) activities that were either more active or as potent as the references particularly as antifungal agents. 相似文献
110.
D. Knittel P. Valenta M. Aydin W. A. König 《Fresenius' Journal of Analytical Chemistry》1985,322(6):581-582
Summary Thiosulfate, a potential substrate for sulfuric acid forming thiobacilli, could be detected and quantitatively determined in corroded concrete sewer systems by differential pulse anodic-stripping voltammetry. The method proved to be specific and gave reproducible results for concentrations from 5 ppb to 3 ppm of thiosulfate in aqueous media.
Spurenanalyse von Thiosulfat in korrodierten Beton-Abwasserkanälen durch differentielle Puls-Anodic-Stripping-Voltammetrie (DPASV)
Zusammenfassung Thiosulfat, ein potentielles Substrat für Schwefelsäure bildende Thiobazillen, konnte in korrodierten Abwasserkanälen aus Beton mittles der differentiellen Puls-Anodic-Stripping-Voltammetrie (DPASV) nachgewiesen und quantifiziert werden. Die Methode erwies sich als spezifisch und ergab reproduzierbare Ergebnisse für Thiosulfatkonzentrationen zwischen 5 ppb und 3 ppm in wäßrigen Medien.相似文献