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1.
Semra Harmandar 《Journal of Quantitative Spectroscopy & Radiative Transfer》2004,84(4):395-407
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.
K. Özker A. Sungur M. Ercan N. Ardagil N. Aydin 《Journal of Radioanalytical and Nuclear Chemistry》1987,118(3):201-208
The labelling of human serum albumin /HSA/ with99mTc has been investigated using a chemical method /stannous citrate/ and electrolytically generated tin/II/ ions. A comparative study of various chemical parameters and current intensities has been carried out in order to find the optimal conditions for labelling. The labelling yield was over 95%, for the chemical and electrolytical methods. 相似文献
4.
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
5.
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
6.
Semra Doğruöz 《Czechoslovak Mathematical Journal》2008,58(2):381-393
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
7.
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
8.
In this study, methanol extracts (MEs) and essential oil (EO) of Angelica purpurascens (Avé-Lall.) Gill obtained from different parts (root, stem, leaf, and seed) were evaluated in terms of antioxidant activity, total phenolics, compositions of phenolic compound, and essential oil with the methods of 2,2-azino-bis(3ethylbenzo-thiazoline-6-sulfonic acid (ABTS•+), 2,2-diphenyl-1-picrylhydrazil (DPPH•) radical scavenging activities, and ferric reducing/antioxidant power (FRAP), the Folin–Ciocalteu, liquid chromatography−tandem mass spectrometry (LC−MS/MS), and gas chromatography-mass spectrometry (GC−MS), respectively. The root extract of A. purpurascens exhibited the highest ABTS•+, DPPH•, and FRAP activities (IC50: 0.05 ± 0.0001 mg/mL, IC50: 0.06 ± 0.002 mg/mL, 821.04 ± 15.96 µM TEAC (Trolox equivalent antioxidant capacity), respectively). Moreover, EO of A. purpurascens root displayed DPPH• scavenging activity (IC50: 2.95 ± 0.084 mg/mL). The root extract had the highest total phenolic content (438.75 ± 16.39 GAE (gallic acid equivalent), µg/mL)). Twenty compounds were identified by LC−MS/MS. The most abundant phenolics were ferulic acid (244.39 ± 15.64 μg/g extract), benzoic acid (138.18 ± 8.84 μg/g extract), oleuropein (78.04 ± 4.99 μg/g extract), and rutin (31.21 ± 2.00 μg/g extract) in seed, stem, root, and leaf extracts, respectively. According to the GC−MS analysis, the major components were determined as α-bisabolol (22.93%), cubebol (14.39%), α-pinene (11.63%), and α-limonene (9.41%) among 29 compounds. Consequently, the MEs and EO of A. purpurascens can be used as a natural antioxidant source. 相似文献
9.
Hasan H. Ince F. Aylin Sungur Konuklar Ilke Ugur Ö. Alaz Ozcan Maryam Sayadi Michael Feig 《Molecular physics》2013,111(23):3839-3848
Deamidation plays an important role in biochemical phenomena such as aging. The role of the n + 1 residue on the deamidation of asparagine (asparagine being the nth residue) in three pentapeptide chains (GGNGG, GGNMG and GGNIG) has been analysed with hybrid computational tools. Potentials of mean force at 300 K were calculated from the MD/replica exchange simulations using weighted histogram analysis (WHAM) in explicit water. The snapshots were clustered taking into account the requirements of the plausible deamidation mechanisms, as such the tautomerisation of the asparagine side chain as initial step has been confirmed, based on the proximity of water to the deamidation site. The ultimate goal being to gain an insight on the peptide backbone N-H acidity, quantum mechanical calculations have been carried out. For this purpose, the distribution of Φ/Ψ, Φ2/Ψ and end-to-end distances deduced from the WHAM diagrams have been considered and a total of 110 structures have been sampled. These neutral pentapeptides as well as their corresponding anions have been optimised (B3LYP/6-31++G(d,p)) in implicit water in order to gain an insight on the peptide backbone N-H acidity. In this study, we have shown that the open conformations of the neutrals and the anions, which display a β sheet like structure are well populated and their pKas rank in the same order as the deamidating half-lives, that is the peptides that deaminate fastest can more readily access conformations that are more acidic. 相似文献
10.
Synthesis and characterization of nanomagnetite particles and their polymer coated forms 总被引:1,自引:0,他引:1
Utkan GG Sayar F Batat P Ide S Kriechbaum M Pişkin E 《Journal of colloid and interface science》2011,353(2):372-379
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