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81.
Allen Y. Chao Dale Eric Wurster Craig W. Davis Dane O. Kildsig 《Drug development and industrial pharmacy》1982,8(2):293-306
Mass transfer from solutions of m-acetotoluide, phenacetin and salicylamide into a stationary solvent, water, was studied. A sharp concentration jump was found at the leading solute front for all three liquid-liquid systmes. A comparison was made between the mass transferred in solid-liquid and liquid-liquid systems. The dissolution of m-acetotoluide, phenacetin and salicylamide was compared with mass transfer of solute from solutions with concentrations Ci, 2Ci and Cs into the pure solvent. In all cases, the amount dissolved from the solid was approximated by the Ci or the 2Ci-solvent system with the amount transferred in the Cs-solvent system approximately 100 fold greater than was dissolved from the solid. It was concluded that a concentration much less than saturation exists at the solid-liquid interface and that dissolution of the three compounds studied is controlled by the rate of solvent interaction at the solid surface. 相似文献
82.
Presents data on undergraduates' sentiments about the history of psychology, based on surveys in the early 1960s (e.g., R. D. Nance [1961]) and the early 1970s. Undergraduates preferred emphasis on contemporary and recent events, although they found the study of history somewhat useful. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Chemical oxygen demands of fourteen nitrogenous compounds were determined by the dichromate method. Only pyridine and its derivatives were resistant to oxidation. Heterocyclic compounds containing one atom of nitrogen in a molecule, e.g. quinoline, pyrrole, proline, and indole were 90–100 per cent oxidized. Nitrogen is split off these compounds as NH3. Heterocyclic compounds containing two or more atoms of nitrogen in a molecule are also easily oxidized. However, only a part of the nitrogen is split off as NH3. On the basis of the results obtained it is possible to make the following generalization: nitrogen in amino groups is split off mostly as NH3; quinoline, pyrrole, pyrrolidine, and indole nitrogen is split off as NH3; from imidazole and pyrimidine rings, one atom of nitrogen is split off as NH3 and one as N2; from the purine configuration, two atoms of nitrogen are split off as NH3 and two atoms as N2; from isoalloxazine, three atoms of nitrogen are split off as NH3 and one as N2. 相似文献
84.
Reports an error in the original article by Dale S. Cannon and Timothy B. Baker (Journal of Consulting and Clinical Psychology, 1981, Vol. 49, No. 1, pp. 20-33). There were a number of instances in which an incorrect inequality sign was used in a statistic. The correct statistics are provided. (The following abstract of this article originally appeared in record 1981-11069-001.) 20 male alcoholic volunteers (mean age 42 yrs) were randomly assigned to 1 of 3 groups: emetic aversion conditioning, shock aversion conditioning, or a no-treatment control group. All Ss participated in psychophysiological assessment sessions and taste-test sessions before and after conditioning. Dependent measures all indicated that only emetic Ss acquired aversions to alcohol. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
The ruthenate compounds, Gd2–zCe
z
Sr2Cu2RuO10, GdSr2Cu2RuO8, and doped Sr2YRuO6, all superconduct in their SrO layers, which is why they have almost the same 49 K onset temperatures for superconductivity. The sister compound Ba2GdRuO6, either doped or not, does not superconduct, because L = 0, J 0 Gd breaks pairs and destroys superconductivity in the potentially superconducting BaO layers. High-temperature superconductivity resides in the SrO or BaO layers, or in interstitial-oxygen regions of the crystal, not in the cuprate-planes. 相似文献
86.
It is often useful to identify and quantify mixture components by analyzing collections of NMR spectra. Such collections arise in metabonomics and many other applications. Many mixtures studied by NMR can contain hundreds of compounds, and it is challenging to analyze the resulting complex spectra. We have approached the problem of separating signals from different molecules in complex mixtures by using self-modeling curve resolution as implemented by the alternating least-squares algorithm. Alternating least squares uses nonnegativity criteria to generate spectra and concentrations from a collection of mixture spectra. Compared to previous applications of alternating least squares, NMR spectra of complex mixtures possess unique features, such as large numbers of components and sample-to-sample variability in peak positions. To deal with these features, we developed a set of data preprocessing methods, and we made modifications to the alternating least-squares algorithm. We use the term "molecular factor analysis" to refer to the preprocessing and modified alternating least-squares methods. Molecular factor analysis was tested using an artificial data set and spectra from a metabonomics study. The results show that the tools can extract valuable information on sample composition from sets of NMR spectra. 相似文献
87.
Klemberg-Sapieha JE Oberste-Berghaus J Martinu L Blacker R Stevenson I Sadkhin G Morton D McEldowney S Klinger R Martin PJ Court N Dligatch S Gross M Netterfield RP 《Applied optics》2004,43(13):2670-2679
Good performance of optical coatings depends on the appropriate combination of optical and mechanical properties. Therefore, successful applications require good understanding of the relationship between optical microstructural and mechanical characteristics and film stability. In addition, there is a lack of standard mechanical tests that allow one to compare film properties measured in different laboratories. We give an overview of the methodology of mechanical measurements suitable for optical coatings; this includes depth-sensing indentation, scratch resistance, friction, abrasion and wear testing, and stress and adhesion evaluation. We used the techniques mentioned above in the same laboratory to systematically compare the mechanical behavior of frequently used high- and low-index materials, namely, TiO2, Ta2O5, and SiO2, prepared by different complementary techniques. They include ion-beam-assisted deposition by electron-beam evaporation, magnetron sputtering, dual-ion-beam sputtering, plasma-enhanced chemical-vapor deposition, and filtered cathodic arc deposition. The mechanical properties are correlated with the film microstructure that is inherently related to energetic conditions during film growth. 相似文献
88.
Discusses 4 phases of the traumatic process associated with severe burn injuries in children. Predisposing factors (i.e., emotional disturbances) in the preinjury phase are discussed. The acute phase centers on treatment directed toward physiological stabilization. The intermediate phase, in which skin grafts and other painful medical procedures are performed, is characterized by dependency on adults and regression, behavior problems, and such emotional reactions as blaming the parents. Strategies for preparing children for and helping them cope with pain are discussed. The rehabilitative phase often involves difficulties in social readjustment. Strategies for dealing with each phase are presented, most of which focus on prevention efforts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
A method is described whereby the precursors of 2-trans-nonenal may be estimated in worts and beers. Treatment of malt grist or malt with a variety of polar substances is shown to reduce or eliminate the production of nonenal precursors during mashing. Beers made from worts so treated have enhanced flavour stability over those made conventionally. 相似文献
90.
Dale N. Treweek James R. Hoyland Carl A. Alexander William M. Pardue 《Journal of hazardous materials》1976,1(3):173-189
A major problem in the transportation, transfer and storage of bulk chemicals is the problem of catastrophic instability under unforeseen situations. N 相似文献