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101.
Eliza Jab?ońska 《Journal of Mathematical Analysis and Applications》2011,381(2):565-572
Let X be a linear space over a commutative field K. We characterize a general solution f,g,h,k:X→K of the pexiderized Go?a?b-Schinzel equation f(x+g(x)y)=h(x)k(y), as well as real continuous solutions of the equation. 相似文献
102.
We describe the atoms of the complete lattice (q(X),⊆) of all quasi-uniformities on a given (nonempty) set X. We also characterize those anti-atoms of (q(X),⊆) that do not belong to the quasi-proximity class of the discrete uniformity on X. After presenting some further results on the adjacency relation in (q(X),⊆), we note that (q(X),⊆) is not complemented for infinite X and show how ideas about resolvability of (bi)topological spaces can be used to construct complements for some elements of (q(X),⊆). 相似文献
103.
Javier Gomez Christian Gemel Christian Slugovc Eliza Wozniak Roland Schmid Karl Kirchner 《Monatshefte für Chemie / Chemical Monthly》2001,30(1):1137-1143
The polymeric compound [Ru(cod)Cl2] x (cod = cyclooctadiene) reacts with 2 equivalents of tmeda (N,N,N′,N′-tetramethylethylenediamine) in refluxing MeOH to afford trans-[Ru(cod)(tmeda)(Cl)(H)] (1), which upon treatment with CHCl3 is readily converted to the dichloro complex trans-[Ru(cod)(tmeda)Cl2] (2). When [Ru(cod)Cl2] x is reacted with tmeda under an atmosphere of H2 (3 bar), the bis-tmeda complex trans-[Ru(tmeda)2Cl2] (3) is obtained in 80% yield. DFT calculations revealed that 3 is by 52 kJ/mol more stable than the corresponding cis isomer. Attempts to prepare the coordinatively unsaturated complex [Ru(tmeda)2Cl]+ by reacting 1 with TICF3SO3 were unsuccessful. According to DFT calculations, however, such a complex should be stable and, interestingly, should adopt a square pyramidal rather than a trigonal bipyramidal structure. If halide abstraction of 3 is performed in the presence of terminal alkynes HC*CR (R*t-Bu, n-Bu), the cationic vinylidene complexes [Ru(tmeda)2(Cl)(*C*CHR)]+ (4a,b) are obtained. 相似文献
104.
Eliza Matuszewska Joanna Matysiak Grzegorz Rosiski Elbieta Kdzia Weronika Zbek Jarosaw Zawadziski Jan Matysiak 《Molecules (Basel, Switzerland)》2021,26(9)
Royal jelly (RJ) is a complex, creamy secretion produced by the glands of worker bees. Due to its health-promoting properties, it is used by humans as a dietary supplement. However, RJ compounds are not fully characterized yet. Hence, in this research, we aimed to broaden the knowledge of the proteomic composition of fresh RJ. Water extracts of the samples were pre-treated using combinatorial hexapeptide ligand libraries (ProteoMinerTM kit), trypsin-digested, and analyzed by a nanoLC-MALDI-TOF/TOF MS system. To check the ProteoMinerTM performance in the MS-based protein identification, we also examined RJ extracts that were not prepared with the ProteoMinerTM kit. We identified a total of 86 proteins taxonomically classified to Apis spp. (bees). Among them, 74 proteins were detected in RJ extracts pre-treated with ProteoMinerTM kit, and only 50 proteins were found in extracts non-enriched with this technique. Ten of the identified features were hypothetical proteins whose existence has been predicted, but any experimental evidence proves their in vivo expression. Additionally, we detected four uncharacterized proteins of unknown functions. The results of this research indicate that the ProteoMinerTM strategy improves proteomic identification in complex biological samples. Broadening the knowledge of RJ composition may contribute to the development of standards and regulations, enhancing the quality of RJ, and consequently, the safety of its supplementation. 相似文献
105.
106.
Ilie G. Dinulescu Sorin Staicu Eliza Avram Filip Chiraleu Margaret Avram 《Journal of organometallic chemistry》1977,136(1):C15-C17
Reaction of phenylmesitylacetylene with dichlorobis(benzonitrile)palladium (BNP) yields a σ-butadienylpalladium complex which on oxidation udergoes cyclisation to give a benzotropone. 相似文献
107.
A synthetic approach to the structurally diverse family of π-expanded diketopyrrolopyrroles is described. A three-step strategy appears to be very general and starts with the preparation of diketopyrrolopyrroles followed by N-alkylation with bromoacetaldehyde diethyl acetal and electrophilic aromatic substitution. The final reaction regioselectively furnishes S-shaped, violet and blue functional dyes of previously unknown structure. New dyes possess sharp absorption and emission peaks, with very high molar absorption coefficients and reasonable fluorescence quantum yields. As a proof of principle, cell uptake of selected dye was demonstrated. 相似文献
108.
Chemoselective reduction of formyl and acetyl derivatives of furan (F) and thiophene (T) to the corresponding carbinols by
2-propanol has been performed in vapour phase over MgO as a catalyst. Formyl derivatives of (F) and (T) have been reduced
to the corresponding carbinols with selectivity 96 and 71%, respectively. Above 573 K the reduction of (T)-CHO was accompanied
by the formation of thiophene whose yield increased with temperature (36% at 723 K). Acetyl derivatives of (F) and (T) have
been reduced to the corresponding carbinols which at higher temperatures underwent dehydration to vinyl derivatives and were
further reduced to ethyl derivatives.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
109.
Andrzej Rykowski Eliza Guzik Mieczyslaw Makosza Wolfgang Holzer 《Journal of heterocyclic chemistry》1993,30(2):413-418
The configuration of (3-substituted)-1,2,4-triazin-5-ylcarbaldoximes and (3-substituted)alkyl-1,2,4-triazin-5-ylketoximes was determined by means of 1H-nmr, 13C-nmr, 15N-nmr and homonuclear NOE-difference spec-troscopy. Oximes resulting from reaction of 1,2,4-triazines with nitroalkanes were found to be either pure E-isomers or E/Z-mixtures with the amount of E-isomer greatly predominating. Detailed 13C-nmr data of the oximes investigated are presented. 相似文献
110.