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111.
Pazderski L Pawlak T Sitkowski J Kozerski L Szlyk E 《Magnetic resonance in chemistry : MRC》2011,49(5):237-241
(1)H, (13)C and (15)N NMR studies of iron(II), ruthenium(II) and osmium(II) bis-chelated cationic complexes with 2,2':6',2″-terpyridine ([M(terpy)(2) ](2+) ; M = Fe, Ru, Os) were performed. Significant shielding of nitrogen-adjacent H(6) and deshielding of H(3'), H(4') protons were observed, both effects being mostly expressed for Fe(II) compounds. The metal-bonded nitrogens were shielded, this effect being much larger for the outer N(1), N(1″) than the inner N(1') atoms, and enhanced in the Fe(II) → Ru(II) → Os(II) series. 相似文献
112.
Agnieszka Iwan Lech Gorecki Damian Pociecha 《Journal of Thermal Analysis and Calorimetry》2012,110(1):43-49
Thermal properties of two azomethine liquid crystals with a benzothiazole core were synthesized and investigated by applied Mettler-Toledo AG equipment (TG/DSC). Azomethines with benzothiazole core was obtained by nucleophilic addition of benzothiazole-2-carboxaldehyde in N,N-dimethylacetamide (DMA) solution with 4-(heptadecafluoroctyl)aniline (BTA1) or 4-hexadecylaniline (BTA2). The differential scanning calorimetry (DSC) was employed to evaluate their phase transitional behavior. Variable heating and cooling rates were used to study liquid crystalline properties of azomethines with benzothiazole core. Compound BTA1 exhibited liquid crystalline properties, while BTA2 is non-mesogenic. Three or four endothermic DSC peaks were observed for both compounds during heating process with the rate 0.5?°C/min. The mesophase was identified and confirmed by XRD study and polarized optical microscopy (POM) too. The thermal stability was determined by thermogravimetric analysis (TG). The temperatures of 5% mass loss (T 5%) of BTA1 and BTA2 range from 212 to 317?°C in nitrogen. 相似文献
113.
Lech Maligranda 《Positivity》2013,17(3):707-710
The $K$ -functional of Peetre is calculated for $p$ -convexifications of normed ideal space as an answer to Lozanovski? problem. 相似文献
114.
Grzegorz Gabor Lech Górniewicz Mirosław Ślosarski 《Set-Valued and Variational Analysis》2009,17(1):1-19
A concept of generalized topological essentiality for a large class of multivalued maps in topological vector Klee admissible
spaces is presented. Some direct applications to differential equations are discussed. Using the inverse systems approach
the coincidence point sets of limit maps are examined. The main motivation as well as main aim of this note is a study of
fixed points of multivalued maps in Fréchet spaces. The approach presented in the paper allows to check not only the nonemptiness
of the fixed point set but also its topological structure.
相似文献
115.
We investigate the semiclassical Weyl formula describing the asymptotic behaviour of the counting function for the number of eigenvalues in the case of self-adjoint elliptic differential operators satisfying weak regularity hypotheses. We consider symbols with possible critical points and with coefficients which have Hölder continuous derivatives of first order.
Mathematics Subject Classification (2000) 35P20. 相似文献
116.
The Nielsen number is defined for a rather general class of multivalued maps on compact connected ANRs, including, e.g., admissible maps (in the sense of Górniewicz (1976); compare also Górniewicz (1995)) on tori. Since the Poincaré maps generated by the Marchaud vector fields are of this type (see (Andres, 1997)), we can obtain in such a way multiplicity results for differential inclusions. More precisely, the nontrivial Nielsen number gives a lower estimate of coincidence points (in particular, fixed points) corresponding to the desired solutions. 相似文献
117.
Lech Sznitko Jaroslaw Mysliwiec Andrzej Miniewicz 《Journal of Polymer Science.Polymer Physics》2015,53(14):951-974
In this review article, we describe the basic principles of random laser operation with particular emphasis on π‐conjugated, dye‐doped and biologically inspired polymers. Random lasers are unusual types of lasers that use disorder in the light amplifying medium to provide positive feedback for laser operation. Organic systems like polymers are affected with disorder resulting both from their molecular structure and fabrication techniques. Due to this fact polymers seem to fit to role of random lasers and now are being extensively studied in this direction. Despite multiline and multidirectional operation polymeric random lasers have potential for several interesting applications. Here we show that they can be successfully applied to sensing in biology and medicine, encoding of information, display technology and search and rescue. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 951–974 相似文献
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120.
Adam S. Plaziak Lech Celewicz Jaroslaw Spychala Krzysztof Golankiewicz 《Journal of mass spectrometry : JMS》1990,25(2):93-96
The electron-impact-induced mass fragmentations of methyl esters of N-(1H-2-oxo-4-pyrimidinyl)ainino acids are reported. The loss of a ·COOCH3 radical and the elimination of a methanol molecule were observed and possible mechanisms of these processes are proposed. The loss of a ·COOH radical and elimination of water were established, which suggests the rearrangement of the investigated esters into isomeric N-4-pyrimidinylamino acids. 相似文献