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1.
Nikolina L. Petrova Dimitar S. Todorovsky Veselinka G. Vasileva 《Central European Journal of Chemistry》2005,3(2):263-278
Mn-, LaMn- and LaCaMn-citrates were synthesized at 60–120°C in ethylene glycol medium using chlorides or nitrates as metal
sources. Their composition, IR spectra and thermal decomposition were studied. Equimolar La/Mn ratio has been established
in the complex, prepared from chloride solution with the same initial composition of the metals. In the isolated three-metallic
complex the molar ratio of the metals deviates from the composition in the initial solution. The final products of the heating
of Mn- and mixed-metal LaMn-citrates at 1000°C are phase-homogeneous Mn3O4 (hausmannite) and LaMnO3 respectively. Parasitic phase(s) are observed in LaxCa1−xMnyO3, produced from LaCaMn-citrate. 相似文献
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Michael G. Sommer Petra Kureljak Dr. Damijana Urankar Dr. David Schweinfurth Nikolina Stojanović Dr. Martina Bubrin Dr. Martin Gazvoda Dr. Maja Osmak Prof. Dr. Biprajit Sarkar Prof. Dr. Janez Košmrlj 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(52):17296-17299
Azocarboxamide (azcH) has been combined for the first time with [Ru–Cym] to generate metal complexes with N,N‐ and N,O‐coordination mode, [(Cym)Ru(azc)Cl] and [(Cym)Ru(azcH)Cl]+[PF6]?. Geometric and electronic structures of the complexes are reported along with their in vitro activities against different tumour cell lines and preliminary results on solution chemistry. Compound [(Cym)Ru(azc)Cl] exhibited remarkable cytotoxic properties. It was cell‐type specific and had comparable IC50 values towards both cancer cells and their drug‐resistant subline. A tenfold increase in the sensitivity towards [(Cym)Ru(azc)Cl] was noted for the tumour cells with depleted intracellular glutathione (GSH) level, suggesting the essential role of GSH in cell response to this compound. 相似文献
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Nikolina Berova Stefan Eojadziev Nevenka Bresciani-Pahor Petko M. Ivanova Biserka Koji-Prodic Rositza Rakovska
Iva Rui-Toro Günther Snatzke 《Helvetica chimica acta》1990,73(7):1853-1860
The absolute configuration of the 2-(phenylmethyl)pyridine derivatives 1 – 9 had been established by X-ray diffraction and chemical correlation. Their CD spectra have been studied in different solvents for the free and protonated forms. It has now been found that, from the sign of the strong CD couplet between 270 and 220 nm, which was observable for all these compounds besides 7 and 9 , their absolute configuration can be determined much quicker. 相似文献
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Bogdan Kurtev Ekaterina Simova Maya Victorova Nikolina Berova Stefanka Christoskova 《Monatshefte für Chemie / Chemical Monthly》1981,112(5):669-673
Diphenylhalonium salts were used in stereospecific N-phenylation of racemic and optically active 3-amino-2,3-diphenyl-1-propanols leading to 3-anilino-2,3-diphenyl-1-propanols. The absolute configurations of the latter and of genetically related compounds were established.
Stereochemische Korrelation von diastereomeren 3-Amino- mit 3-Arylaminosäuren bzw. ihrer Derivate durch stereospezifische N-Phenylierung mit DiphenylhaloniumsalzenKurze Mitteilung
Zusammenfassung Durch stereospezifische N-Phenylierung mit Hilfe von Diphenylhaloniumsalzen werden racemische sowie optische aktive 3-Amino-2,3-diphenyl-1-propanole in die entsprechenden 3-Anilino-2,3-diphenyl-1-propanole übergeführt. Auf Grund dieser Umwandlung wird die absolute Konfiguration der Aminoalkohole und davon abgeleiteter Derivate ermittelt.相似文献
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Nikolina L. Petrova Dimitar S. Todorovsky Daniela G. Kovacheva Maria M. Milanova 《Central European Journal of Chemistry》2006,4(4):632-645
Al-and Y-Al-citric complexes have been synthesized in ethylene glycol medium at conditions close to the ones used in polymerized
complex method and their composition and spectral characteristics have been studied. Proofs have been found for the formation
in the bimetallic system of a mixed-metal Al-Y-complex. Doubly ionized and esterified ligands take place in the Al-complex.
All of the ligands forming Y-Al-complex are mono-or doubly esterified. Deprotonation of the alcoholic group takes place in
the formation of the mixed-metal complex. Both complexes contain adduct-bonded ethylene glycol. Heating of the bimetallic
complex or of the polyester resin formed leads to not phase-homogeneous YAlO3-along with cubic YAlO3, its orthorhombic modification as well as Y4Al
l2O9 are found by X-ray diffractometry. 相似文献
7.
Vassileva ND van den Ende D Mugele F Mellema J 《Langmuir : the ACS journal of surfaces and colloids》2006,22(11):4959-4967
We consider single two-dimensional aggregates, containing glass particles, placed at a water/air interface. We have investigated the critical shear rate for break-up of aggregates with different sizes in a simple shear flow. All aggregates break-up nearly at the same shear rate (1.8 +/- 0.2 s(-)(1)) independent of their size. The evolution of the aggregate structure before break-up was also investigated. With increasing shear rate, the aggregates adopt a more circular shape, and the particles order in a more dense, hexagonal structure. A simple theoretical model was developed to explain the experimentally observed break-up. In the model, the aggregate is considered as a solid circular disk that will break near its diameter. The capillary and drag force on the two parts of the aggregate were calculated, and from this force balance, the critical shear rate was found. The model shows a weak size dependence of the critical shear rate for the considered aggregates. This is consistent with the experimental observations. 相似文献
8.
Ludmila Parashkevova Jordanka Ivanova Nikolina Bontcheva 《Comptes Rendus Mecanique》2004,332(7):493-498
The thermo-elastic plastic behaviour of functionally graded plates under extremal thermal loading at different boundary conditions is considered. The plates consist of two phases – ZrO2 ceramics and Ti6Al4V alloy. The layers are distributed exponentially through the thickness. The mechanical and thermal properties of both materials strongly depend on temperature. The stress–strain behaviour is investigated by the FEM. To predict the stable state of the structures of interest, several failure criteria are applied. Two cost functions are introduced to optimize the design of the plate. The main results are discussed and graphically illustrated. To cite this article: L. Parashkevova et al., C. R. Mecanique 332 (2004). 相似文献
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