Low frequency Δν̄=0–350 cm−1, Raman intensity data were obtained from liquid water between 3.5 and 89.3 °C using holographic grating double and triple monochromators. The spectra were Bose–Einstein (BE) corrected, I/(1+n), and the total integrated (absolute) contour intensities were treated by an elaboration of the Young–Westerdahl (YW) thermodynamic method, assuming conservation of hydrogen-bonded (HB) and nonhydrogen-bonded (NHB=bent and/or stretched, O–H O) nearest-neighbor O–O pairs. A ΔH°1 value of 2.6±0.1 kcal/mol O–H ⋅⋅⋅ O or 5.2±0.2 kcal/mol H2O (11 kJ/mol O–H ⋅⋅⋅ O, or 22 kJ/mol H2O) resulted for the HB→NHB process. This intermolecular value agrees quantitatively with Raman and infrared ΔH° values from the one- and two-phonon OH-stretching regions, and from molecular dynamics, depolarized light scattering, neutron scattering, and ultrasonic absorption, thus indicating a common process. A population involving partial covalency of, i.e., charge transfer into, the H ⋅⋅⋅ O units of linear and/or weakly bent hydrogen bonds, O–H ⋅⋅⋅ O; is transformed into a second high energy population involving bent, e.g., 150° or less, and/or stretched, e.g., 3.2 Å, but otherwise strongly cohesive O–H O interactions. All difference spectra from the fundamental OH-stretching contours cross at the X(Z,X+Z)Y isobestic frequency of 3425 cm−1. Also, total integrated Raman intensity decreases occurring below 3425 cm−1 with temperature rise were found to be proportional to the total integrated intensity increases above 3425 cm−1, indicating conservation among the HB and NHB OH-stretching classes. From the enthalpy of vaporization of water at 0 °C, and the ΔH°1 of 2.6 kcal/mol O–H ⋅⋅⋅ O, the additional enthalpy, ΔH°2, needed for the complete separation of the NHB O–O nearest neighbors is ∼3.2 kcal/mol O–H ⋅⋅⋅ O or ∼6.4 kcal/mol H2O (13 kJ/mol O–H ⋅⋅⋅ O or 27 kJ/mol H2O). The NHB O–O nearest neighbors are held by forces other than those involving H ⋅⋅⋅ O partial covalency, i.e., electrostatic (multipole), induction, and dispersion forces. The NHB O–O pairs do not appear to produce significant intermolecular Raman intensity because they lack H ⋅⋅⋅O bond polarizability, but the corresponding NHB OH oscillators do contribute weakened Raman intensity above 3425 cm−1. An ideal solution thermodynamic treatment employing ΔH°1 =2.6 kcal/mol O–H ⋅⋅⋅ O, the HB mole fraction, and the vapor heat capacity, yielded a very satisfactory specific heat value of 1.1 cal deg−1 g−1 H2O at 0 °C. The NHB mole fraction, fu, from the YW treatment is negligibly small, 0.06 or less, for t<−50 °C. However, fu increases to 0.16 at 0 °C, and fu≊1 at 1437 °C, where recent shock-wave Raman measurements indicate loss of all partially covalent, charge transfer hydrogen bonding.
Six employee characteristics (conscientiousness, self-efficacy, motivation to learn, learning goal orientation, performance goal orientation, instrumentality) and one work environment characteristic (transfer of training climate) were captured for 130 trainees in a large industrial company in an attempt to predict training effectiveness (training grade, supervisor evaluation of the application of training). The results strongly support the predicted links, although not all the predictor variables contributed a statistically significant share of the explained variance of the training outcomes. Motivation to learn and learning goal orientation were found to contribute most to predicting training outcomes. The implications of the results are discussed and the limitations of the study are noted, along with suggested avenues for future research.
Benzo[a]pyrenebutyric acid (B[a]PBA) has been synthesized and covalently coupled to bovine serum albumin to generate monoclonal antibodies (Mab). A competitive indirect enzyme-linked immunosorbent assay (ELISA) for polycyclic aromatic hydrocarbons (PAH) has been developed with Mab B[a]P-13. It was shown by testing with 21 parent PAH and 10 compounds carrying methyl, hydroxy, or butyric acid functions that the antibody had broad specificity. Highest affinity was found for four- to six-ring PAH. Different organic co-solvents were tested. No loss in sensitivity, compared with controls in PBS, were found with methanol, dimethyl sulfoxide, and glycerol at final concentrations of 5 to 10%. Further, an observation was made that a modification (fine-tuning) of the affinity and specificity of the antibodies was possible by changing the type of the added organic co-solvent. The high susceptibility of the ELISA with regard to inorganic ions might be an indication of a more hydrophilic binding pocket e.g. involving a pi-cation interaction. Investigation of the effect of pH revealed that for pH between 6 to 9 there was no noticeable impairment. With an LOD as low as 30 pg per well for B[a]P the sensitivity of the ELISA is sufficient for analyses of solvent extracts of many environmental samples. As an example, the determination of a PAH sum parameter, given as B[a]P-equivalents, in crude aerosol extracts by both ELISA and HPLC revealed good correlation (r2=0.717) but approximately five-fold overestimation by the immunochemical method, obviously as a result of cross-reacting analytes.
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