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Under ambient humid conditions, the adsorption of acetaldehyde on unmodified TiO2 is small and weak. In contrast, loading Au particles smaller than 3 nm on TiO2 with surface area larger than 17.5 m2 g−1 (Au/TiO2) causes the rapid and strong adsorption of gaseous acetaldehyde from a closed space. This striking adsorption phenomenon initiates from the aerobic oxidation of acetaldehyde to acetic acid by the thermocatalysis of Au/TiO2 at room temperature. Acetic acid is moved to the TiO2 surface to be dissociated to acetate ion and proton, which are adsorbed on the Lewis acid and base sites on the surface, respectively. The resulting reproduction of the catalytic sites for the acetaldehyde oxidation enables the continuous removal of acetaldehyde without the release of the harmful product. Further, the adsorbed species on Au/TiO2 are completely oxidized to CO2 by the post-heating at 548 K, whereas the oxidation degree of acetate adsorbed on unmodified TiO2 remains several % even at 570 K with harmful products (Quah et al., 2010).

Effects of cyclic oligosaccharide cyclodextrin (CD) on stability and conformation of lysozyme were clarified thermodynamically and rheologically by DSC, viscosity, and circular dichroism measurements. The modified β-CD relatively destabilized the folded state of lysozyme by stabilizing the unfolded state due to inclusion of hydrophobic part into the hydrophobic interior of CD. The order of higher destabilization effect was acetyl-β-CD > methyl-β-CD > hydroxypropyl-β-CD. Apparent number of bound CD to unfolded state for methyl-, hydroxypropyl-, and acetyl-β-CD is 6.7 ± 0.7, 4.2 ± 1.1, and 18.6 ± 4.3 and the binding constant is 5.5 ± 0.8, 6.7 ± 2.4, and 4.4 ± 1.2 L mol −1 , respectively. The viscosity for unfolded state was increased with an increase in the each modified β-CD concentration, suggesting that the inclusion of CD on a part of hydrophobic core at unfolded state leads to break the hydrophobic core, then lysozyme would be more spread structure. The substituent of CD can accelerate instability by directly breaking hydrogen bond and/or can restrain instability by increase in hydrophobic interaction. The fact that the each modified CDs has different destabilization effect shows a possibility to control the stability of protein by the substitution of CD.

Excess enthalpies for binary mixtures ( S -fenchone + ethanol/benzene/cyclohexane/carbon tetrachloride) were measured over the whole concentration at T = 298.15 K. The experimental results were compared with the values obtained from the UNIFAC, COSMO-RS and regular solution theory. Excess enthalpies of binary mixtures of R -fenchone and S -fenchone in ethanol, benzene, and cyclohexane solution at different specified mole fractions of fenchone have been measured under the same conditions. With the decreasing of the specified mole fraction of fenchone in different solutions, the excess enthalpies of mixing of chiral orientated solutions increased and became close to zero. Results were compared with those of chiral limonene in ethanol solution. Pair interaction energies were also investigated.

Enthalpies of mixing and the densities of ethanol solution of R - and S -enantiomers of camphor, 10-camphorsulfonamide, 10-camphorsulfonic acid, camphorquinone, and 10-camphorsulfonyl chloride have been measured for a wide range of mole fractions of heterochiral components at 298.15 K. Enthalpies of mixing were exothermic for all concentrations and heterochiral solutions were more stable than each of the homochiral solutions. Enthalpic stabilization of mixing of heterochiral solutions was increased with a decreasing concentration of all the camphor derivatives measured. The sequence of enthalpic stabilization on mixing was 10-camphorsulfonyl chloride, 10-camphorsulfonic acid, 10-camphorsulfonamide, camphor, and camphorquinone. Apparent molar volumes were determined and excess volumes of mixing of heterochiral solutions were small and negative. Enthalpic stabilizations were found to be dependent on dipole–dipole interaction between solutes and solvents.

The molar excess enthalpies of 1,2- and 1,3-propanediamine + 1- or 2-propanol and 1,2- and 1,3-propanediol + 1- or 2-propaneamine have been determined at 298.15 K using a twin-microcalorimeter for a series of runs over the whole range of mole fractions. All excess enthalpies were large exothermic, in particular, the systems of amines + propanediols were more than −5 kJ mol −1 at the minimum. Primary or secondary alcohols and amines showed systematically different enthalpic behaviors. Equilibrium constant K1 expressed in terms of mole fractions and standard enthalpy of the formation of a 1:1 complex have been evaluated by ideal mixtures of momomeric molecules and their associated complexes.

Enthalpies of mixing of (R)- and (S)-enantomers of liquid chiral compounds such as benzyl-(1-phenyl-ethyl)-amine (1), 1-phenylethylamine (2), 1-phenyl-ethanol (3), butyric acid oxiranylmethyl ester (4), 4-methyl-[1,3]dioxolan-2-one (5), 2-Chloromethyloxirane (6) and 3-hydroxyisobutyric acid methyl ester (7) have been measured over the whole range of mole fractions at 298.15 K, albeit very small values. Mixing of heterochiral liquids of R-1 + S-1, R-5 + S-5, and R-7 + S-7 realized enthalpic stabilization over the whole range of mole fractions, whereas that of R-2 + S-2, R-3 + S-3, R-4 + S-4, and R-6 + S-6 realized enthalpic destabilization over entire compositions. The extreme values of enthalpies of mixing and the intermolecular interaction obtained by the molecular mechanics calculations showed a linear correlation, except few the compounds measured.

Excess enthalpies of nine mixtures between methyl methylthiomethyl sulfoxide (MMTSO) or dimethyl sulfoxide (DMSO) and each of aliphatic alcohols { CH 3 ( CH 2 ) n OH , n=3–11} have been determined at 298.15 K. All the systems show the positive enthalpies over the whole range of mole fraction. Excess enthalpies of MMTSO+alcohols are larger than that of DMSO+alcohols and increased with increasing the number of methylene groups of alcohols. The excess partial molar enthalpies at infinite dilution of butane-1-ol showed the boundary between the two linear relationships obtained between those of MMTSO or DMSO and dipole–dipole interaction of aliphatic alcohols { CH 3 ( CH 2 ) n OH , n=0–11} -sulfoxides.

Enthalpies of solution of aliphatic alcohols {CH 3 (CH 2 ) n OH, n = 0-10} and aliphatic nitriles {CH 3 (CH 2 ) n CN, n = 0-12} in dimethyl sulfoxide (DMSO) have been determined at 298.15 K for the mole fraction range 5 x 10 -5 to 0.002. In all cases enthalpies of solution were found to be positive. Partial molar enthalpies of solution at infinite dilution were derived. Linear relations between the limiting excess partial molar enthalpies and the number of methylene groups were found for both groups of compounds investigated. McMillan-Mayer's parameters, h xx and h xxx , showed unfavorable and favorable interactions, respectively.

The inclusion complexation of ampicillin (ABPC) with β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (HPCD) in aqueous solution has been investigated by microcalorimetry, NMR spectrometry and molecular dynamics simulation (MDS). The heat of reaction of the complexation decreased as the pH value increased. ABPC and β-cyclodextrins formed one or two types of inclusion complexes by hydrophobic interactions and the complexation significantly depended on the species of ABPC based on the pH values of the solutions. Two different types of inclusion complexes with a 1:1 stoichiometry were realized for the cation species of ABPC in the strong acid solution. In the first type of inclusion with higher association constants of (6.0–10)×10 3 M −1 , the penam ring of ABPC was inserted in the cyclodextrin cavity, whereas in the second type with lower association constants of 1.0×10 3 M −1 , the phenyl ring seemed to penetrate into the cavity. The β-lactam ring of ABPC was included in both types to be protected from the acid-catalyzed hydrolysis. The zwitterion and anion species of ABPC formed only one type of inclusion complex with β-cyclodextrins, where the phenyl ring and the penam ring were included, respectively. These association constants and enthalpic changes were smaller than those for the first type inclusion complex of the cation species. These results indicate that the inclusion complexes of ABPC with β-cyclodextrins would be useful to the drug delivery system.

Enthalpies of mixing of ( R )- and ( S )-enantiomers of liquid chiral compounds such as heptane-2-ol, octane-2-ol, nonane-2-ol, 3-chloro-propane-1,2-diol and 2-methyl-1,4-butanediol have been measured over a range of mole fractions at 298.15 K, albeit very small values. Mixing of heterochiral liquids of heptane-2-ol, octane-2-ol, nonane-2-ol, 3-chloro-propane-1,2-diol, realized enthalpic destabilization over the whole range of mole fractions, whereas that of 2-methyl-1,4-butanediol realized enthalpic stabilization over entire compositions. The maximum values of enthalpies of mixing and the intermolecular interaction of cohesive energy density and entropy of vaporization showed a linear correlation except for the compounds having two chiral centers and others.

Excess enthalpies of binary mixtures between each of alkane-1-amines {C n H 2 n +1 NH 2 , n =3–8} and methyl methylthiomethyl sulfoxide (MMTSO) or dimethyl sulfoxide (DMSO) have been determined at 298.15 K. All mixtures showed positive enthalpy changes over the whole range of mole fractions. The limiting excess partial molar enthalpies of the aliphatic amines, H 1 E,∞ , of all the mixtures with MMTSO or DMSO studied were smaller than those of MMTSO or DMSO, H 2 E,∞ , respectively. Linear relations are obtained between limiting excess partial molar enthalpies and number of methylene groups.

Cholesterol sulfate (CS) and sulfatides in the epithelium of the digestive tract were found in the 1000xg supernatants of digestive fluid, particularly in gastric juices containing the duodenal contents and bile acids, there being 14-131 microg of CS and 3-54 microg of sulfatides per mg of protein in the fluid, respectively. CS and sulfatides dissolved in detergents including bile acids inactivated pancreatic trypsin to the same level as by DMSO-solubilized sulfated lipids at 37 degrees C. Similarly, pancreatic DNase I was inhibited by CS solubilized with DMSO or bile acids, but not by sulfatides or other membrane lipids at 37 degrees C. Both the sulfate group and the hydrophobic side chain of CS were indispensable structures for the inhibition of DNase I. Also, the optimum molar ratio of bile acids to CS was important for expression of the inhibitory activity of CS toward DNase I, it being 0.18 of the optimum ratio for sodium taurocholate, and the molar ratio of CS to DNase I for complete inhibition was 342:1. Thus, CS was shown to play a role as an epithelial inhibitor of DNase I in concert with bile acids.

Precise and accurate values of the excess enthalpies of{xC6H6 + (1 − x)C6D6} ,{xC6H12 + (1 − x)C6D12} and{xCH2Cl2 + (1 − x)CD2Cl2} have been determined over the whole composition range at T = 298.15 K. Although all the excess enthalpies are small, those of{xC6H6 + (1 − x)C6D6} and{xC6H12 + (1 − x)C6D12} are endothermic and those of{xCH2Cl2 + (1 − x)CD2Cl2} are exothermic. A linear correlation is found between the excess enthalpies at x = 0.5 and the reciprocal of the number of deuterium atoms bound to the carbon atoms of a deuterated compound.

To determine the enthalpies and entropies of inclusion, enthalpies of dilution of dilute aqueous 1,4-butanediol (BD) solutions and those of transfer of 1,4-BD from aqueous to aqueous α- or β-cyclodextrin (CD) solutions have been determined by microcalorimetry at various mole fractions at 298.15 K. Enthalpies of inclusion of 1,4-BD molecules into α- and β-CD cavities are determined, whose values are exothermic and small. However, stabilisation of gaseous 1,4-BD molecules in the CD cavities is large. 1,4-BD molecules must change their conformations to make the closest contacts with the atoms on the wall of α-CD cavities or those on the wall of β-CD cavities and the remaining water molecules in β-CD cavities.

Excess enthalpies of binary mixtures between one of the alkylbenzenes (ethylbenzene, n -propylbenzene, n -butylbenzene, n -pentylbenzene, n -hexylbenzene, n -heptylbenzene and n -octylbenzene) and methyl methylthiomethyl sulfoxide (MMTSO) or dimethyl sulfoxide (DMSO) have been determined at 298.15 K. For all the mixtures, changes in enthalpy are positive over the whole range of mole fractions. Linear relationships are obtained between the limiting excess partial molar enthalpies H E,∞ 1 and H E,∞ 2 and ( α 2 μ 2 1 + α 1 μ 2 2 ) V −1 1 V −1 2 , where α and μ are the polarizabilities and electric dipole moments of the alkylbenzenes(1) and the sulfoxides(2), respectively, and V the molar volumes of 1 or 2. Phase separations are observed for the binary mixtures containing alkylbenzenes higher than n -butylbenzene. Mutual solubilities determined are decreased with increase of sizes of alkyl radicals. In homogeneous regions, all the molar excess enthalpies are increased with increase of the size of alkyl radicals.

Carbon soot was generated by laser ablation under oxygen-free and regulated-temperature conditions at 300 K and 1500 K. The soot was significantly oxidised by being exposed to air in darkness. The degree of oxidation was determined to be 0.038±0.012 and 0.093±0.009 for the high temperature (HT) soot and the low temperature (LT) soot, respectively, on the basis of elemental analysis, XPS and Karl-Fischer titration. Water physically absorbs on the soot in proportion to the degree of oxidation. TG, TPD and 13C-NMR revealed that there were at least 2 kinds of oxidised states. One of them mainly contributes to CO and CO2 emissions at 420–970 K, while another contributes to CO emission above 770 K. The former is a dominant oxide in the LT soot. On the basis of FT-IR and 13C-NMR spectra, carbonyl groups were confirmed to be one of the major oxidised species in the soot. FT-IR and acid-base titration revealed that the LT soot adsorbed more CO2 than the HT soot did. The adsorbed CO2 contributes to the acidic property of the soot. The soot is paramagnetic as well as conductive. C1s and Auger photoelectron spectra of the soot were neither graphite-like nor diamond-like. The air oxidation is discussed in relation to unique structures and formation mechanisms of the soot.

Excess molar volumes of methyl methylthiomethyl sulfoxide (MMTSO)+monohalogenated aromatic compounds (fluorobenzene, chlorobenzene, bromobenzene, 4-fluorotoluene and 4-chlorotoluene) have been measured at 298.15 K over the whole range of mole fractions. Those of the halogenated aromatic compounds+dimethyl sulfoxide (DMSO) have also been determined for the reference systems. All mixtures show volume contraction except for bromobenzene and 4-fluorotoluene+DMSO. The volume contractions of MMTSO systems on mixing are larger than those of corresponding DMSO systems. The correlation between limiting excess partial molar volume and limiting excess partial molar enthalpies are given.

The enthalpy of dilution of dilute aqueous solution of meso -2,3-butanediol, x −3 , and enthalpy of inclusion of meso -2,3-butanediol into α - and β -cyclodextrin cavities in dilute aqueous solutions have been determined by using a rocking twin-microcalorimeter of a heat-conduction type at 298.15 K under atmospheric pressure. The enthalpies of inclusion of meso -2,3-butanediol into α - and β -cyclodextrins are exothermic and smallest among three isomers, 1,3-, 1,4- and meso -2,3-butanediols. The correlation between behaviors and molecular shapes are discussed.

Excess enthalpies of binary mixtures between each of ortho - and meta -isomers of dihalogenated benzenes (difluorobenzene, dichlorobenzene, dibromobenzene) and methyl methylthiomethyl sulfoxide (MMTSO) or dimethyl sulfoxide (DMSO) have been determined at 298.15 K. All mixtures showed positive enthalpy changes over the whole range of mole fractions except m -difluorobenzene+DMSO. Excess enthalpies of m -difluorobenzene+DMSO have small two maxima and one negative minimum. Excess enthalpies of the mixtures containing dichlorobenzene showed the largest enthalpy among the halogenated benzene+MMTSO. Linear relations are obtained between limiting excess partial molar enthalpies and the products of square of dipole moment divided by limiting partial molar volume of the components, except the mixture of o -difluorobenzene+DMSO.

Excess enthalpies of binary mixtures between each of chlorobenzene, fluorobenzene, bromobenzene, chlorotoluene and fluorotoluene and methyl methylthiomethyl sulfoxide (MMTSO) or dimethyl sulfoxide (DMSO) have been determined at 298.15 K. All mixtures showed positive enthalpy change over the whole range of mole fractions. Partial molar enthalpies of the mixtures containing MMTSO(2) around 0.95 in mole fraction have maxima and minima. Linear relations are obtained between limiting excess partial molar enthalpies and the square of the dipole moment except H 2 E,∞ of the mixtures containing fluorotoluene.

Excess enthalpies of six binary mixtures between methyl methylthiomethyl sulfoxide (MMTSO) or dimethyl sulfoxide (DMSO) and one of the dialkylethers (diethylether, ethylpropylether or dipropylether) have been determined at 298.15 K. All the mixtures observed showed positive excess enthalpies over the whole range of mole fractions and miscibility gaps. The mutual solubilities decreased with the increase in size of the alkyl radicals. Excess enthalpies determined at saturated mole fractions also decreased with the increase in size of the alkyl radicals. The enthalpies and entropies of transfer between conjugate mixtures were determined. The excess enthalpies of the mixtures containing DMSO were larger than those containing MMTSO. A comparison of the results with those for six binary mixtures containing a cyclic ether is made.

Enthalpies of dissolution in water of dialkylsulphides: CH 3 (CH 2 ) v S (CH 2 ) v CH 3 , v = 0, 1, and 2, and dialkyldisulphides: CH 3 (CH 2 ) v S S (CH 2 ) v CH 3 , v = 0 and 1, were determined by microcalorimetry at the temperatures (288.15, 298.15, 308.15, and 328.15) K. Molar enthalpies of solvation and partial molar heat capacities at 298.15 K were derived for the infinitely dilute solutions. The partial molar heat capacities are discussed in terms of an empirical group scheme.

Excess enthalpies of five mixtures between methyl methylthiomethyl sulfoxide (MMTSO) and five methylbenzenes, i.e., toluene, o -xylene, m -xylene, p -xylene or 1,3,5-trimethylbenzene, have been determined at 298.15 K. All the mixtures show the positive enthalpy changes over the whole range of mole fractions. Excess enthalpies of MMTSO + methylbenzenes are smaller than that of corresponding dimethyl sulfoxide(DMSO) + methylbenzenes and are increased with the increase of the number of methyl groups in the methylbenzenes. Linear relationships are obtained between the number of methyl groups of methylbenzenes and the excess partial molar enthalpies of MMTSO and benzene, toluene, m -xylene and 1,3,5-trimethylbenzene at infinite dilution.

To compare the difference between the thermodynamic properties of binary mixtures containing methyl methylthiomethyl sulfoxide ( mmtso ), CH 3 (CH 3 SCH 2 )SO, and those containing dimethyl sulfoxide ( dmso ), excess molar volumes for the title mixtures have been determined by use of bicapillary pyknometers. The signs of excess volumes and their temperature coefficients for the mixtures containing mmtso are similar to those for the corresponding mixtures of dmso . The curve of excess molar volume for (water + dmso ) plotted against mole fraction x of dmso shows an inflection point in the range: x

Densities of benzene + o-terphenyl have been measured as a function of composition at 288.15, 298.02, and 302.78 K by means of the pyknometric method. The density of the supercooled melt of o-terphenyl has also been measured from 288.15 to 313.19 K. The excess molar volumes and the excess partial molar volumes of the components are evaluated from the densities measured. The excess volumes are all negative at these temperatures, and they are more negative when the temperature is increased.

Enthalpies of dilution of o-terphenyl in benzene were measured calorimetrically at 288.15, 293.15, 298.15, 303.15, and 308.15 K. In the range of the volume fraction near the solubilities to high dilutions, φ2 ≈ 0.7 to 0.04, enthalpies of dilution observed are all positive. The enthalpy parameter χH and its dependence on volume fraction calculated from experimental results are reproduced by the linear functions: 0.0911−0.01 0 φ2, 0.0799+0.0074 φ2, 0.0685+0.0036 φ2, 0.0624 + 0.0054, φ2, and 0.0568−0.0022 φ2, respectively at 288.15, 293.15, 298.15, 303.15, and 308.15 K, where φ2 is a volume fraction of o-terphenyl. These observations show that χH decreases with rise of temperature. A comparison of χH among the isomers at 298.15 K show that the relative order of energetic affinity for benzene in solution is ortho- > meta- > para-terphenyls.

The speeds of sound u and densities ϱ of {xo-C6H4(C6H5)2 + (1 − x)C6H6} for (x < 0.106) and {xp-C6H4(C6H5)2 + (1 − x)C6H6} for (x < 0.0041) were measured at 298.15 K, except for ϱ of the second mixture which was measured at 298.73 K. Isentropic compressibilities κS were estimated from the results. The apparent partial molar values of o- and p-terphenyls are also given and discussed.

The molar excess enthalpies HmE of the title mixtures have been determined by using a twin-microcalorimeter of the heat-conduction type which requires only 10 cm3 of each component liquid for a series of runs over the whole range of mole fractions. The HmE of CDCl3 + CHCl3 is nearly athermal and its maximum value is 9 J mol−1. The HEm of CDCl3(1) + CH3SOCH2,SCH3(2) and DMSO(2) are exothermic. The minimum values of HmE are −2.27 kJ mol−1 at x2 = 0.4 for the former mixture and −2.91 kJ mol−1 at x2 = 0.4 for the latter. An equilibrium constant K1 expressed in terms of mole fractions and standard enthalpy ΔH1XXX of formation of a 1:1 associated complex between CDCl3 and CH3SOCH2SCH3 have been evaluated to be K1 = 3.8 and ΔH1XXX (101325Pa) = −6.6 kJ mol−1, by assuming an ideal mixture of CDCl3, CH3SOCH2SCH3 and their 1:1 and 2:1 associated complexes. The enthalpic stabilization on hydrogen bonding between CDCl3 and CH3SOCH2SCH3 molecules is smaller than that between CHCl3 and CH3SOCH2SCH3 molecules by about 23%.

As a test of the overall performance of the calorimetric system used, the enthalpy of solution of tris(hydroxymethyl)aminomethane in 0.100 mol dm−3 aqueous HCl at 298.15 K was measured. For the crushed and vacuum-dried preparation it was −(29.794 ± 0.006) kJ mol−1 which agrees with −(29.790 ± 0.013) kJ mol−1 reported by Rychlý and Pekarek. By use of this calorimeter, the enthalpies of solution ΔHsoln/kJ mol−1 and standard deviations σ/kJ mol−1 of o-, m-, and p-terphenyls in benzene at 298.15 K were found to be ( 15.57+21.85 n 2 n 1 ), σ = 0.05; ( 24.04−2.83 n 2 n 1 ), σ = 0.08; ( 31.46−5.48 n 2 n 1 ), σ = 0.12; respectively, in very dilute solutions, where n2 and n1 are the amounts of terphenyl and benzene. The enthalpies of solution at higher mole fractions are also given for o- and m-terphenyls. The enthalpies of solvation have been estimated.

The Swietoslawski's differential ebulliometer has been minimized to be usable for ca. 13 cm 3 of liquid. After a performance test with acetone, the vapour pressure of hexamethyldisilane is determined over the temperature range 304.61–386.74 K. The Antoine equation obtained is log 10 ( P /kPa) = 5.97097 − 1319.85/{( T /K) − 52.96} and the normal boiling point is 385.81 K. The present results agree with literature values of Suga and Seki at 287–310 K and Brockway and Davidson at 293–334 K.

A short summary of the milestones to the present stage of achievement by the authors, some problems encountered in their course of investigations, and their countermeasures are described. A precise experimental results of the excess enthalpy for (cyclohexane + n -hexane) at (298.15 ± 0.001) K are given as a reliability test of the microcalorimetry with small amounts of samples. A couple of enthalpy-entropy compensation rules in the formation equilibria of inclusion complexes between α- and β-cyclodextrins and some alcohols in water at 298.15 K are described, which have been found from their calorimetric determination of the enthalpies and entropies of inclusion after overcoming the problems.