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91.
Dragana Krstic Zoran Jovanovic Vladimir Markovic Dragoslav Nikezic Vlade Urosevic 《Central European Journal of Physics》2014,12(10):714-718
The Boron Neutron Capture Therapy (BNCT) is based on selective uptake of boron in tumour tissue compared to the surrounding normal tissue. Infusion of compounds with boron is followed by irradiation with neutrons. Neutron capture on 10B, which gives rise to an alpha particle and recoiled 7Li ion, enables the therapeutic dose to be delivered to tumour tissue while healthy tissue can be spared. Here, therapeutic abilities of BNCT were studied for possible treatment of liver cancer using thermal and epithermal neutron beam. For neutron transport MCNP software was used and doses in organs of interest in ORNL phantom were evaluated. Phantom organs were filled with voxels in order to obtain depth-dose distributions in them. The result suggests that BNCT using an epithermal neutron beam could be applied for liver cancer treatment. 相似文献
92.
For finite semidistributive lattices the map κ gives a bijection between the sets of completely join-irreducible elements and completely meet-irreducible elements.Here we study the κ-map in the context of torsion classes. It is well-known that the lattice of torsion classes for an artin algebra is semidistributive, but in general it is far from finite. We show the κ-map is well-defined on the set of completely join-irreducible elements, even when the lattice of torsion classes is infinite. We then extend κ to a map on torsion classes which have canonical join representations given by the special torsion classes associated to the minimal extending modules introduced by the first and third authors and A. Carroll in 2019.For hereditary algebras, we show that the extended κ-map on torsion classes is essentially the same as Ringel's ?-map on wide subcategories. Also in the hereditary case, we relate the square of κ to the Auslander-Reiten translation. 相似文献
93.
Marjan Piponski Tanja Bakovska Stoimenova Stefan Stefov Trajan Balkanov Gordana Trendovska Serafimovska Liliya Logoyda 《Journal of separation science》2020,43(17):3482-3490
Fast, simple, accurate, and reproducible reverse phase‐high‐performance liquid chromatography method with direct ultraviolet measurement of memantine hydrochloride in tablets was developed, without any chemical derivatization pretreatment. Three main problems appear during chromatographic analysis of memantine: detection, achieving appropriate column retention, and limited choice of mobile phase components, as a result of memantine molecular structure. Among more than 35 tested columns, the best retention and peak symmetry yielded two C8 and three C18 columns with different characteristics, at a temperature of 30°C, mobile phase composed of 1%, v/v, acetonitrile and 99%, v/v, of 0.05–0.1% phosphoric acid or 2.5–5 mmol phosphate buffer, at flow rate of 1 mL/min and injection volume of 5 µL. The retention time of memantine was between 2.6 and 4 min. Both mobile phase concepts showed perfect linearity, precision, and accuracy. This is the first successful and reproducible direct reverse phase‐high‐performance liquid chromatography–ultraviolet quantification method for memantine. 相似文献
94.
Berta Holló Marko V. Rodić Ljiljana S. Vojinović-Ješić Vukosava Živković-Radovanović Gordana Vučković Vukadin M. Leovac Katalin Mészáros Szécsényi 《Journal of Thermal Analysis and Calorimetry》2014,116(2):655-662
The synthesis of a potentially bioactive mixed-valence CoIII/CoII complex with 2-acetylpyridine S-methylisothiosemicarbazone (HL) ligand is described. The crystal and molecular structure of the formed [CoIIIL2][CoIICl3 py]·Me2CO (I) compound (py stands for pyridine) is determined by single-crystal X-ray crystallography. It’s thermal decomposition along with the decomposition of the ligand and six structurally related complexes with formulas [CoL2]NO3·MeOH (1), [CoL2]Br·MeOH (2), [CoL2]HSO4·MeOH (3), [CoL2]2[CoII(NCS)4] (4), [Co(HL)(L)]I2·2MeOH (5), and [Co(HL)(L)][CoIICl4]·MeOH (6) was determined by simultaneous TG/DSC measurements. The decomposition pattern is evaluated using TG/DTA-MS data. The results were related to the solvent/moisture content and the decomposition mechanism of the compounds. The antimicrobial activity of the ligand and of all the complexes was tested in vitro for selected gram-negative and gram-positive bacteria and fungi. The activity of the ligand against all tested bacteria is comparable with those obtained for standard antibiotics, while it is less active against fungi. Surprisingly, the activity of the complexes is very low. The low antimicrobial activity of the complexes may be in connection with their high thermodynamic and kinetic inertness in solution. The results are also supported by the relatively high thermal stability of the complexes. 相似文献
95.
Alan R. Katritzky Giuseppe Musumarra Kumars Sakizadeh Sayed M.M. El-Shafie Bratislav Jovanovic 《Tetrahedron letters》1980,21(28):2697-2699
-Substituents in 2, 4, 6-triphenylpyridiniums are transferred to piperidine, morpholine and pyridine by unimolecular and/or bimolecular processes in chlorobenzene solution. These processes are quite distinct and afford no evidence for a mechanism intermediate between SN1 and SN2. 相似文献
96.
Robert Katava Sandra Kraljević Pavelić Anja Harej Tomica Hrenar Gordana Pavlović 《Structural chemistry》2017,28(3):709-721
The in situ condensation reaction of 2-hydrazinobenzothiazole with salicylaldehyde, 3,4-dihydroxybenzaldehyde, 2,4-dihydroxybenzaldehyde, 2,5-dihydroxybenzaldehyde, 2,3-dihydroxybenzaldehyde, 2-hydroxy-1-naphthaldehyde, 2-methoxy-1-naphthaldehyde, 4-methoxy-1-naphthaldehyde and 6-methoxy-2-naphthaldehyde produced 9 hydrazone Schiff bases (L1–L9, respectively) which were identified and characterized by elemental analysis, IR and NMR spectroscopy. The crystal and molecular structures of four Schiff bases (L1, L7–L9) have been determined by the single-crystal X-ray diffraction method confirming the imino form of L1 and the amino tautomeric form of L7–L9 compounds. Molecular structure analysis also confirmed that reported compounds are E-isomers relative to exo C = N imino bond. The Nhydrazino–H group of amino tautomers forms Nhydrazino–H···Nthiazolyl intermolecular hydrogen bonds shaping molecules into R 2 2 (8) rings, while imino tautomer of L1 forms C(4) infinite helical chains via Nthiazolyl–H···Nhydrazino type of intermolecular hydrogen bond. The methoxy group (L7–L9) further shaped these primary supramolecular synthons into different supramolecular arrangements via C–H···O, C–H···N and C–H···S intermolecular hydrogen bonds. The role of aryl substituents in the shaping and stabilization of supramolecular architectures of L1, L7–L9 is supported by quantum chemical calculations. Strong antiproliferative effects on tumor cells and cytotoxic effects on fibroblasts are shown for all ligands L1–L9 with exception of L6 and L7 that had no effect on fibroblast cells. 相似文献
97.
We numerically investigate time-dependent rotation of counterpropagating mutually incoherent self-trapped Gaussian beams in periodic optically induced fixed photonic lattices. We demonstrate the relation between such rotation and less confined discrete solitonic solutions. 相似文献
98.
Z. Huang D. French H.-Y. Pao I. Jovanovic 《Applied physics. B, Lasers and optics》2011,102(3):607-613
Classical information theory can be used to quantify the resolution performance of optical imaging systems. When an optical parametric amplifier (OPA) operated as a phase-sensitive amplifier (PSA) in the transverse spatial domain is used for point source imaging, the angular resolution improvement can approach the de Broglie resolution (i.e. Heisenberg limit). In this paper, classical information theory is employed to quantify the signal-to-noise ratio (SNR) improvement for both an ideal and a realistic multimode PSA applied to the problem of sub-Rayleigh imaging. When only considering the noise originating from the detector, the SNR improvement is found to scale quadratically as a function of the PSA gain, in the limit of noise power comparable to signal power. Differences in performance of an ideal PSA and a realistic PSA are discussed. 相似文献
99.
Adel S. A. Alimmari Bojan ?. Bo?i? Aleksandar D. Marinkovi? Du?an ?. Mijin Gordana S. U??umli? 《Journal of solution chemistry》2012,41(10):1825-1835
A series of 4,6-disubstituted-3-cyano-2-pyridones was synthesized and their UV?CVis absorption spectra were recorded in the region 200?C600?nm in the set of selected solvents. The effects of solvent dipolarity/polarizability and solvent?Csolute hydrogen-bonding interactions on the spectral shifts were analyzed by means of the linear solvation energy relationship concept of Kamlet and Taft. The influence of solvents as well as substituents on the 2-pyridone/2-hydroxypyridine tautomeric equilibration was evaluated. The absorption band maximum of the 2-hydroxypyridine form is found to appear at a shorter wavelength than that of the 2-pyridone form in all investigated solvents. The replacement of the methyl and phenyl groups at position 6 of the pyridone ring, by a hydroxy group, significantly changes the solvatochromic behavior of the investigated pyridones. 相似文献
100.
Milija Suknovic Boris Delibasic Milos Jovanovic Milan Vukicevic Dragana Becejski-Vujaklija Zoran Obradovic 《Computational Statistics》2012,27(1):127-148
We propose a generic decision tree framework that supports reusable components design. The proposed generic decision tree
framework consists of several sub-problems which were recognized by analyzing well-known decision tree induction algorithms,
namely ID3, C4.5, CART, CHAID, QUEST, GUIDE, CRUISE, and CTREE. We identified reusable components in these algorithms as well
as in several of their partial improvements that can be used as solutions for sub-problems in the generic decision tree framework.
The identified components can now be used outside the algorithm they originate from. Combining reusable components allows
the replication of original algorithms, their modification but also the creation of new decision tree induction algorithms.
Every original algorithm can outperform other algorithms under specific conditions but can also perform poorly when these
conditions change. Reusable components allow exchanging of solutions from various algorithms and fast design of new algorithms.
We offer a generic framework for component-based algorithms design that enhances understanding, testing and usability of decision
tree algorithm parts. 相似文献