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41.
The heats of dissolution of benzene, chlorobenzene, ortho-dichlorobenzene, nitrobenzene, and aniline in n-hexane and 1-butanol and those of benzene, chlorobenzene, nitrobenzene, and aniline in a mixture of n-hexane and 1-butanol were measured by calorimetry at 25°C. The enthalpies of solvation of the compounds were calculated. The correlation between the enthalpies of solvation of the compounds and their molar refraction was studied. The enthalpies of solvation of the compounds and their functional groups by the mixture of n-hexane and 1-butanol were considered.  相似文献   
42.
Tri(m-tolyl)antimony bis(1-adamantanecarboxylate) (3-MeC6H4)3Sb[OC(O)C10H15]2 has been synthesized with a yield of 90.0% by the reaction of tri(m-tolyl)antimony with 1-adamantanecarboxylic acid in the presence of hydrogen peroxide in ether. According to X-ray diffraction analysis data, the antimony atom has a distorted trigonal-bipyramidal coordination with the axially positioned oxygen atoms of carboxyl groups. The axial OSbO angle is 173.1(2)°; the equatorial CSbC angles are 112.0(1)°, 112.0(1)°, and 136.0(3)°; the Sb-O distance is 2.109(3)Å; the Sb-C distances are 2.103(5), 2.103(5), and 2.121(7) Å; intramolecular Sb…O(=C) contacts are 3.069(5) Å.  相似文献   
43.
Using the aggregation numbers of micelles and the effective sizes of hydrated surfactant ions and counterions of the first coordination sphere, we calculated the average geometric characteristics of the surface layer of ionic spherical micelles in solutions of the sodium n-alkyl sulfate homologues with n C = 8, 10, 12, and 14 carbon atoms in the molecule; in particular, we established 1) the size of the micelle core; 2) the thickness of the electrical double layer on the surface; 3) the mutual arrangement parameters of hydrophilic and hydrophobic ions; 4) the number of “free” water molecules and showed their dependence on the homologue number and the degree of binding of counterions.  相似文献   
44.
Titanium(4+) and zirconium(4+) complexes with pyridinedicarboxylic acid derivatives have been synthesized. The composition and structure of the synthesized 2,6-bis(diphenylhydroxymethyl)pyridine complexes have been corroborated by NMR and IR spectroscopy, and elemental analysis. The complexes activated with methylaluminoxane (MAO) are catalytically active in ethylene polymerization, Depending on the Ti/AlMAO ratio, the catalytic activity of the complexes varies between 90 and 420 kg PE/mol Ti h atm.  相似文献   
45.
Transition Metal Chemistry - In this study, Ni(II) and Co(II) complexes [Co(H2O)2L2] (1), [Ni(H2O)2L2] (2), [Co(phen)L2] (3), [Ni(phen)L2]·2H2O·EtOH (4·2H2O), and...  相似文献   
46.
Doklady Physical Chemistry - The ionic and phase compositions of Y2.5Ce0.5Fe2.5Ga2.5O12 ferrogarnet samples obtained by gel combustion with subsequent vacuum annealing were studied for the first...  相似文献   
47.
Journal of Analytical Chemistry - Silver nanoparticles modified with Eu3+ ions increase the intensity of the fluorescence signal by a factor of 125 in an analytical system containing doxycycline as...  相似文献   
48.
Development of sustainable bio-based materials for removal of toxic contaminants from water is a high priority goal. Novel bio-based binary and ternary copolymers with enhanced ion-exchange, adsorption and antibacterial properties were obtained by using plant biomass-derived diallyl esters of furandicarboxylic acid (FDCA) as crosslinking agents and easily available vinyl monomers. The synthesized copolymer materials showed higher sorption capacities for NiII, CoII and CuII compared to the commercial ion-exchange resins, and they maintained their high metal adsorption capacities for over 10 cycles of regeneration. The synthesized copolymer gels containing 1–5 wt % of the crosslinker showed excellent water absorption capacities. The synthesized copolymers with 1 % crosslinker content showed swelling ratios high enough to also act as moisture absorbents. Synthesized copolymers with crosslinker content of 10 wt % performed as contact-active antibacterials by inhibiting the growth of Gram-positive (S. aureus) and Gram-negative bacteria (E. coli, K. pneumonia) in suspension tests.  相似文献   
49.
The protonation and alkylation of cross-conjugated ketones containing a terminal N-methylpyrrole ring takes place at the oxygen atom. Protonation is accompanied by a strong bathochromic shift of the absorption maximum in the electron spectrum, while alkylation leads to ethoxypolymethine salts. The possibility of using these salts for the synthesis of ethoxycyanine dyes was studied.  相似文献   
50.
The thermodynamic properties of styrenetricarbonylchromium, -methylstyrenetricarbonylchromium, and p-methylstyrenetricarbonylchromium were studied with adiabatic vacuum and dynamic calorimeters. The heat capacity in the range 5-450 K (error about 0.3% in most cases) and the temperatures and enthalpies of the phase transitions were determined. The experimental data were used to calculate the thermodynamic functions C 0 p(T), H 0(T) - H 0(0), S 0(T), and G 0(T) - H 0(0) for the range from 0 to 330-400 K, and also the isochoric heat capacity C v and its lattice (Cv,latt) and atomic (C v,at) contributions for the range from 0 K to T 0 m; the parameters = C 0 p/C v were evaluated. The thermodynamic properties were considered in relation to the composition and structure of the compounds.  相似文献   
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