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1.
Journal of Thermal Analysis and Calorimetry - This work introduces the determination of the optimum values of the design parameters in a tube with loose-fit perforated twisted tapes. The effects of...  相似文献   
2.
We give a characterization of realcompact spaces in terms of nets. By using the technique of this characterization we give easy proofs of the Tychonoff Theorem and the Alaoglu Theorem.

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3.
In this paper we give a characterization of order ideals in Riesz spaces.

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4.
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   
5.
In the doubly odd 63 150 Eu87 nucleus a 45 ns 8+ isomer at 589 keV excitation has been identified through (p, 3n) in beamγ ande ? measurements. The low lying negative parity levels populated in its decay show great similarity to analogous states in the lighter odd-odd Eu neighbours suggesting a spherical shape for150Eu. A spherical shape is also proposed for the isomer which is assigned as (πh 11/2 vf 7 2/?3 )8+ state analogous to the 9+ isomers known in148Eu and146Eu. The spin change is attributed to the crossing of the half-filledf 7/2 neutron shell atN=86.  相似文献   
6.
Detailed Fe vibrational spectra have been obtained for the heme model complex [Fe(TPP)(CO)(1-MeIm)] using a new, highly selective and quantitative technique, Nuclear Resonance Vibrational Spectroscopy (NRVS). This spectroscopy measures the complete vibrational density of states for iron atoms, from which normal modes can be calculated via refinement of the force constants. These data and mode assignments can reveal previously undetected vibrations and are useful for validating predictions based on optical spectroscopies and density functional theory, for example. Vibrational modes of the iron porphyrin-imidazole compound [Fe(TPP)(CO)(1-MeIm)] have been determined by refining normal mode calculations to NRVS data obtained at an X-ray synchrotron source. Iron dynamics of this compound, which serves as a useful model for the active site in the six-coordinate heme protein, carbonmonoxy-myoglobin, are discussed in relation to recently determined dynamics of a five-coordinate deoxy-myoglobin model, [Fe(TPP)(2-MeHIm)]. For the first time in a six-coordinate heme system, the iron-imidazole stretch mode has been observed, at 226 cm(-)(1). The heme in-plane modes with large contributions from the nu(42), nu(49), nu(50), and nu(53) modes of the core porphyrin are identified. In general, the iron modes can be attributed to coupling with the porphyrin core, the CO ligand, the imidazole ring, and/or the phenyl rings. Other significant findings are the observation that the porphyrin ring peripheral substituents are strongly coupled to the iron doming mode and that the Fe-C-O tilting and bending modes are related by a negative interaction force constant.  相似文献   
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8.
Designing new inhibitors having less side effects is a need which also could reduce cholesterol levels. To fulfill this aim, we have carried out a molecular docking study toward 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase. A set of designed structural derivatives of statin drugs, eight ligands which are used as HIV-1 integrase inhibitor candidates, a set of terpenoids, and ligands downloaded from Zinc15 database were docked to HMG-CoA reductase enzyme which contains atorvastatin in crystal structure. The analysis of docking studies revealed that statin derivative ligands are more appropriate for inhibition of HMG-CoA reductase. To define the contribution of the molecular properties to the binding of ligands to enzyme structure; the highest occupied molecular orbitals-lowest unoccupied molecular orbitals, hardness, electronegativity, and chemical potential properties of ligands have best score in their sets calculated by quantum mechanical tools.  相似文献   
9.
We calculate the electronic properties of austenite and martensite Fe-9%Mn alloys using the self consistent full-potential linearized-plane-wave method under the generalized gradient approximation full lattice relaxation. By minimizing total-energy, the lattice constants in their ground states were determined. We discuss the total energy dependence of the volume, and density of states (DOS).   相似文献   
10.
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