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1.
A new batch titration microcalorimeter has been used for estimation of thermodynamic properties in various investigated colloidal systems. As examples, we present enthalpic and kinetic data obtained from this calorimetric device for four different processes widely encountered in colloid science:
(i)  The dilution/micellization process of cationic gemini surfactants in aqueous solution.
(ii)  The hydration process of non ionic surfactants in organic solution, i.e. the mechanism of micellar solubilization of water in the aggregates.
(iii)  The complexation of calcium ions by polyacrylates sodium salts (PaNa).
(iv)  The adsorption phenomenon of PaNa molecules on the calcium carbonate surface.
This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

2.
1.  The trimethylsilyl derivatives of deacylated acidic nitrogen-free phospholipids have been analyzed quantitatively by GLC. Using the flame-ionization detector, correction coefficients have been calculated with respect to the trimethylsilyl ester of octadecanol.
2.  Simultaneous use of thermionic and flame-ionization detectors facilitates the qualitative interpretation of analytical results.
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3.
1.  The rate constant for the destruction of radical pairs decreases with increase in the distance between the traps of the H atom.
2.  A mechanism was proposed for the destruction of radical pairs, according to which the main channel for hydrogen transfer during annealing does not coincide with the channel for phototransfer when the RP are formed.
3.  Based on a formally kinetic analysis for a stepwise rate, distribution parameters based on the activation energies were found for the deuterated and undeuterated samples. A superficial estimate was made of the change in the activation energy when the distance between the unpaired electrons in the radical pairs is changed by one unit of length.
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4.
1.  A method is proposed for investigating fast reactions of aroxyl radicals. The kinetic parameters obtained for the reaction of 2,4,6-tri-t-butylphenoxyl with phenol and with 4-bromophenol coincide with the data obtained by other methods.
2.  From an analysis of the kinetic data, it is concluded that the OH bond energy in 4-methyl-2,6-di-t-butylphenol is close to that in 2,4,6-tri-t-butylphenol.
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5.
1.  Complexes of the REE, Y, and Sc with hydroxyethylethylenediaminetriacetic acid have been isolated in solid form. The hydrate compositions of the complexes have been determined.
2.  The La and Pr complexes form hydrates of different compositions. The LnL hydrates form slightly nonisostructural groups in the series La-Lu.
3.  According to thermographic analysis data, the hydrate water in the LnL·nH2O complexes of different hydrate compositions is not bonded with the same firmness.
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6.
To mitigate CO2 discharged from thermal power plants, studies on CO2 fixation by the photosynthesis of microalgae using actual exhaust gas have been carried out. The results are as follows.
1.  A method is proposed for evaluating the maximum photosynthesis rate in the raceway cultivator using only the algal physical properties;
2.  Outdoor cultivation tests taking actual flue gas were performed with no trouble or break throughout 1 yr using the strain collected in the test;
3.  The produced microalgae is effective as solid fuel; and
4.  The feasibility studies of this system were performed. The system required large land area, but the area is smaller than that required for other biomass systems, such as tree farms.
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7.
1.  The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical.
2.  In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane.
3.  The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers.
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8.
1.  In liquid-phase reactions chlorine fluorosulfate is a more effective reagent for replacement of a chlorine atom in Freons by the fluorosulfate group than peroxydisulfuryl difluoride.
2.  These processes and the reaction of peroxydisulfuryl difluoride with carbon monoxide in the liquid phase take place only in the presence of fluorosulfonic acid.
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9.
Ethylene-olefin copolymers differ from other polyethylenes in that:
there is no long chain branching;
short chain branching is determined by the comonomer unit;
the molecular mass distribution is sharp;
the side chain distribution on different molecules is broad;
the sequential distribution of branching is very broad along the molecular chains, which becauses a multi-peak lamella distribution, and a multi-peak melting heat.
With the help of a cross-fractionation method we interpreted the differences of the experimental data, according to the molecular mass fractionation and the branching received.  相似文献   

10.
1.  Vinyl- and isopropenyl-o-carborane are hydrogenated under the reaction conditions for the hydroformylation and carboxylation of olefins in the presence of cobalt or rhodium carbonyls.
2.  A mechanism was proposed for the hydrogenation of olefin-o-carboranes in alcohol solutions under CO pressure.
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11.
1.  In NaA zeolite a homocharge is formed by charges deposited on the surface of the zeolite from the gas gap between the electrode and the specimen.
2.  The existence of thermoelectret effects has been found in the systems NaA-zeolite -air, NaA-helium, NaA-nitrogen, and NaA-oxygen.
3.  The thermoelectret effects are caused by both the accumulation of charges in the specimen and the adsorption of molecules in the electric field.
4.  A low mobility has been noted for adsorbed molecules in the electret state of the system.
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12.
1.  Nitroxyl biradicals of the triazine, N,N-bis(triazinyl)ethylenediamine, N,N-bis(triazinyl)piperazine, and s-nitropyrimidine series have been prepared.
2.  The ESR spectra of liquid and frozen solutions of these biradicals have been obtained and N. - O group separations calculated.
3.  Toluene solutions of (II), (V), (VI), and (X) biradicals contain at least four different conformations, each with its own value of the exchange integral.
4.  In one of the biradical (V) conformations, spin interaction exchange is through the chain of atoms linking the N.-O fragments.
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13.
1.  It has been shown that 2-bromo-l,3,2-dioxaarsenanes exist in chair conformation with axially oriented As-Br bonds.
2.  Polarity and polarizability parameters have been found for the As-O and As-Br bonds in 2-bromo-l,3,2-dioxaarsenanes.
3.  The so-called -effect is stronger in the O2AsBr group than in the O2AsCl group.
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14.
1.  The ellipsoids of polarizability of dimethylsulfone, sulfuryl chloride, and methanesulfonyl chloride were determined, and the nonadditivity of the parameters of the bonds in the sulfonyl chloride group was demonstrated.
2.  Substituted methane sulfonyl chloride exist in gauche conformations.
3.  In benzenesulfonyl chloride and a series of its para-substituted derivatives, the aryls are situated in the C-S-Cl plane; the para-nitro group induces a 35° rotation.
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15.
1.  Complexes of platinum with polyethyleneimine have been synthesized and characterized by spectroscopic methods.
2.  It has been shown that the complex Pt(II)-PEI, reduced with sodium borohydride, is an active and selective catalyst for the hydrogenation of aromatic nitro-compounds.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1499–1503, July, 1989.  相似文献   

16.
1.  The molecular-sieve properties of a number of synthetic and natural chabazites have been investigated.
2.  Characteristic differences have been revealed in the molecular-sieve properties, thermal stability, and x-ray characteristics between the two groups of the zeolites studied.
3.  A reversal of the molecular-sieve effect on passing from the calcium to the sodium-calcium forms of certain synthetic and natural chabazites has been observed.
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17.
1.  A procedure has been developed for carrying out the reaction between ozone and paraffins directly in an EPR resonator.
2.  EPR signals of the products of the reaction between ozone and paraffins in the liquid phase have been obtained.
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18.
1.  Depending on the nature of the substituent in the 2 position, l-fluoro-l-(-hydrohexafluoroisopropyl)ethylenes are dehydrofluorinated to either allenes or 1,3-dienes.
2.  It was shown that allylic substitution is possible in the reactions of perfluoroisobutylene with carbanions; the mutual transformations of the allyl and vinyl isomers were studied.
3.  The perfluoroalkenylation product was obtained when perfluoroisobutylene is reacted with ketene acetal.
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19.
1.  We determined the reactivity of some nitrogen bases, and of a number of amino acids and bis-(diazoacetyl)alkyl derivatives toward the electron at 77°K.
2.  The effect of the pH at 77°K as established on the yield of the deamination process and the reactivity of the studied amino acids toward the electron.
3.  It was found that the yield for the deamination of glutamic acid is increased in the presence of inositol (acceptor of OH radicals).
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20.
1.  The planar alkoxydiazinoxide fragments are shown to have the Z-configuration and be orthogonal to each other by an x-ray structure study of a series of alkoxydiazinoxides.
2.  In the oxydiazinoxide fragments, p- conjugation occurs.
3.  The molecules of the compounds in the crystals studied are joined by hydrogen bonds.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 297–301, February, 1989.  相似文献   

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