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1.
A radiation code based on method of lines solution of discrete ordinates method for radiative heat transfer in axisymmetric cylindrical enclosures containing absorbing-emitting medium was developed and tested for predictive accuracy by applying it to (i) test problems with black and grey walls (ii) a gas turbine combustor simulator enclosing a non-homogeneous absorbing-emitting medium and benchmarking its steady-state predictions against exact solutions and measurements. Comparisons show that it provides accurate solutions for radiative heat fluxes and can be used with confidence in conjunction with CFD codes based on the same approach.  相似文献   
2.
The centrosymmetric title compound, [Cd2{CH3OC6H4P(OC5H9)S2}4], features an eight‐membered [? Cd? S? P? S? ]2 ring owing to the presence of bridging dithiolate ligands. Tetrahedral coordination geometries for cadmium are completed by chelating ligands. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
3.
Determining the structural behavior of masonry structures is a challenge due to their lack of homogeneity. The seismic behavior of masonry structures is especially complex. The aim of this study was to examine the structural behavior of Za?anos Bastion using both experimental and numerical methods. The Operational Modal Analysis technique, including the Enhanced Frequency Domain Decomposition Method, and the Stochastic Subspace Identification Method were used to illustrate experimentally the dynamic characteristic of the bastion. A finite element model was developed using ANSYS software in order that the dynamic characteristics of the bastion, including natural frequencies and mode shapes, could be calculated numerically. Seismic analysis was carried out using the 1999 Kocaeli earthquake ground motion record to determine the linear and nonlinear seismic behavior of the bastion. The Turkish Earthquake Code and its general technical specifications were used to evaluate the seismic results. The results show that the maximum and minimum principal stresses exerted on the masonry components exceeded the code requirements at some points, but in general the requirements for the stresses were satisfied.  相似文献   
4.
We introduce the class of restricted k[A]-modules and p t -Jordan types for a finite abelian p-group A of exponent at least p t and a field k of characteristic p. For these modules, we generalize several theorems by Benson, verify a generalization of conjectures stated by Suslin and Rickard giving constraints on Jordan types for modules of constant Jordan type when t is 1. We state conjectures giving constraints on p t -Jordan types and show that many p t -Jordan types are realizable.  相似文献   
5.
In the present work, effects of gamma radiation on solid meropenem trihydrate (MPT), which is the active ingredient of carbapenem antibiotics, were investigated by electron spin resonance (ESR) spectroscopy. Irradiated MPT presents an ESR spectrum consisting of many resonance peaks. Heights measured with respect to the spectrum baseline of these resonance peaks were used to explore the evolutions of the radicalic species responsible for the experimental spectrum under different conditions. Variations of the denoted 11 peak heights with microwave power, sample temperature and applied radiation doses and decay of the involved radicalic species at room and at high temperatures were studied. On the basis of the results derived from these studies, a molecular model consisting of the presence of four different radicalic species was proposed, and spectroscopic parameters of these species were calculated through spectrum simulation calculations. The dosimetric potential of MPT was also explored and it was concluded that MPT presents the characteristics of normal and accidental dosimetric materials.  相似文献   
6.
Threonine Schiff base derived 2-hydroxy-1-naphthaldehyde and threonine has been isolated and investigated. The stoichiometry of this compound was derived from the results of elemental analyses, IR, 1H-NMR and UV spectroscopic techniques. X-ray diffraction method was also used to obtain the single-crystal structure. The compound crystallizes in the space group P21 with cell dimensions a=5.109(2), b=11.334(2), and β=91(3)° with Z=2. The molecule has phenol-imine tautomeric form in the crystal structure. Some of bond lengths and angles found in the molecular structure are distorted due to π-electron delocalization and steric effect of naphthylidene and threonine groups.  相似文献   
7.
An R-module M is said to be an extending module if every closed submodule of M is a direct summand. In this paper we introduce and investigate the concept of a type 2 τ-extending module, where τ is a hereditary torsion theory on Mod-R. An R-module M is called type 2 τ-extending if every type 2 τ-closed submodule of M is a direct summand of M. If τ I is the torsion theory on Mod-R corresponding to an idempotent ideal I of R and M is a type 2 τ I -extending R-module, then the question of whether or not M/MI is an extending R/I-module is investigated. In particular, for the Goldie torsion theory τ G we give an example of a module that is type 2 τ G -extending but not extending.  相似文献   
8.
This paper reports the preparation and characterization of novel thin film electrolytes by UV cross-linking of poly(propylene glycol) diacrylate in the presence of polyetheramine (glyceryl poly(oxypropylene)triamine) and LiTFSI. The oligomeric surfactant polyetheramine facilitates self-assembly of the electrolyte, enabling it to be applied conformally onto a complex substrate which is necessary for 3D-microbatteries, while the acrylate network supplies mechanical stability. Conformal coatings onto LiFePO4 electrodes and Cu nanopillars were confirmed by SEM. Ionic conductivities of 3.5 × 10− 6 and 5.8 × 10− 5 S/cm were measured at room temperature and 60 °C, respectively, at Li:O = 1:20 and PEA:PPGDA = 2:1 ratios. The electrochemical stability window test showed that the electrolyte is stable above 5.0 V vs. Li/Li+. Thermal analyses by TGA and DSC demonstrated that the polymer electrolyte is amorphous and thermally stable up to 300 °C.  相似文献   
9.
10.
Superparamagnetic nanoparticles were prepared by coprecipitation of ferrous (Fe(2+)) and ferric (Fe(3+)) aqueous solution by a base. Nanomagnetite particles were coated with poly(St/PEG-EEM/DMAPM) and poly(St/PEG-MA/DMAPM) layer by emulsifier-free emulsion polymerization. Chemical structure of nanoparticles was characterized by both FTIR and (1)H NMR. Particle morphologies were determined by Zeta Sizer, DLS, XRD and SAXS. Structural analysis showed that after polymer coating nanomagnetite particles kept their superparamagnetic property. Besides the synthesized magnetites, polymer coated forms of these particles are more biocompatible, well dispersable and uniform. These properties make them a very strong candidate for bioengineering applications, such as bioseparation, gene transfer.  相似文献   
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