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11.
Examined the extent to which the 36 items of the Rokeach Value Survey (RVS) provide comprehensive and representative coverage of the value domain in 2 experiments. In Exp I, intensive semistructured interviews, based on the RVS, were conducted with 73 adults drawn from an electoral roll. Test–retest reliabilities were examined over 4 wks with 208 university students. In Exp II, factor structure was explored with 483 adults from the general population and with 688 university students. All Ss completed inventories of goal values, mode values, and social values. Data provide qualified support for the comprehensiveness of the instrument. The major weaknesses in sampling involved the facets of physical well-being and individual rights. Other areas not represented were thriftiness and carefreeness. The need for multi-item indices for value constructs is discussed, as are the advantages of a rating procedure over a ranking procedure from both psychometric and empirically valid perspective. An alternative instrument based on the work of Rokeach is proposed. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
The Middle Palaeocene Beda Formation, penetrated by wells in block NC74F in the SW Sirt Basin, is dominated by lagoonal, intertidal, and supratidal rocks including evaporites originally deposited in a restricted shallow lagoon.
In the area studied, about 60% of the formation has been dolomitized. Dolomite occurs predominantly replacing precursor carbonate mudstones, although pore-filling cements line moulds and vugs. Replacive crystals are euhedral to subhedral, finely to very finely crystalline, and generally less than 0.03 mm in diameter. They are non-ferroan, and show a uniform dull-to-moderate orange luminescence. Crystals forming cements are coarser, up to 0.35 mm in diameter, and are characteristically baroque.
Geochemical data indicate that the Beda dolomites have high strontium, low iron, and low manganese contents. They are also depleted in18 O, with negative δ18 O values averaging -3.63% (PDB). The 13 C values show a more marine δ13 C isotopic signature, with an average δ13 C value of +3.33% (PDB).
The petrographic and geochemical characteristics of the Beda dolomites and their association with evaporites supports a model of early, near-surface, dolomitization resulting from hypersaline brine refluxion. 相似文献
In the area studied, about 60% of the formation has been dolomitized. Dolomite occurs predominantly replacing precursor carbonate mudstones, although pore-filling cements line moulds and vugs. Replacive crystals are euhedral to subhedral, finely to very finely crystalline, and generally less than 0.03 mm in diameter. They are non-ferroan, and show a uniform dull-to-moderate orange luminescence. Crystals forming cements are coarser, up to 0.35 mm in diameter, and are characteristically baroque.
Geochemical data indicate that the Beda dolomites have high strontium, low iron, and low manganese contents. They are also depleted in
The petrographic and geochemical characteristics of the Beda dolomites and their association with evaporites supports a model of early, near-surface, dolomitization resulting from hypersaline brine refluxion. 相似文献
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More than in the case of the other major fertiliser elements the performance of phosphorus in fertilisers in dependent on the state of chemical combination of the element. As distinct from typical American practice where fully acidulated fertilisers are emphasised, some other countries have moved in part to production of materials of less than full acidulation where some reliance is placed on the reactivity of the original phosphate rock. Solutions of various aliphatic acids and their salts have been used as tests for the availability of phosphorus in fully acidulated fertilisers and, to a degree, for phosphate rocks themselves. Less than fully acidulated products are at present assessed in the same way as fully acidulated materials, but in this and other evaluations problems and anomalies arise which are discussed within the framework of a number of fertiliser systems. Analytical data are adduced which illustrate the effects of some extraneous cations on the results achieved which conflict with some previous opinions. Research towards a fuller understanding of the subject is suggested. 相似文献
16.
C. J. R. Braithwaite 《Journal of Petroleum Geology》1986,9(3):343-348
Devonian dolomites are described, in which broken grains and internal crystal silts are associated with stylolites and pressure-solution seams. These features are interpreted as resulting from a progressive mechanical collapse, following dissolution of anhydrite. The transfer of loading by failure within the rock unit was responsible for stress concentrations, which led to the initiation of the stylolites with fluids driven out by compaction. The evidence suggests occlusion of a formerly extensive, vuggy, porosity. 相似文献
17.
African-American physicians and dentists in metropolitan Atlanta were surveyed to assess smoking cessation practices and perceptions. Questionnaires were mailed to 373 physicians and 90 dentists. A total of 154 questionnaires were returned, for an overall response rate of 33.3%. More physicians than dentists considered smoking a "very serious" threat to patients' health, and physicians were more likely to document smoking status in charts and to counsel smokers to quit. Physicians also were approached more frequently by patients seeking cessation advice. Both types of practitioners considered the nicotine patch, formal cessation programs, and behavior modification/psychotherapy to be among the most effective cessation methods, and nicotine gum and acupuncture to be among the least effective. These results indicate African-American physicians are much more involved than dentists in promoting smoking cessation among patients. Advice of health professionals generally is viewed as a powerful influence for African-American patients. Further work is needed to utilize fully the power of health care providers, especially dentists, in the fight against tobacco-related morbidity and mortality. 相似文献
18.
The chemical analyses of different size fractions of a variety of commerical and laboratory prepared samples of partially acidulated phophate rocks and mixtures of reactive phosphate rock and single superphosphate (called LONGLIFE in New Zealand) have been studied. Whereas only minor chemical segregation effects have been observed for partially acidulated products quite a large bias has been established for LONGLIFE materials, and more especially commercial samples, where larger proportions of phosphate rock were found in the lower size fractions. This inhomogeneity was considered to arise from poor mixing of components and subsequent inconsistent granulation; more stringent rejection criteria for undersize material would greatly assist in improving the product quality. Chemical deactivation of the phosphate rock residue in LONGLIFE materials was also observed; this can be partially explained by a selective reaction of the reactive phosphate rock component with acid still present at the time of mixing with the single superphosphate component. 相似文献
19.
The 2% citric and formic acid solubilities of phosphate rock residues extracted from partially acidulated materials (20 and
35% acidulation) manufactured from two phosphate rocks (both ground and unground) in the presence of monocalcium phosphate,
monosodium phosphate, calcium chloride, calcium sulphate, calcium carbonate, sodium carbonate and aluminium and iron sulphates
have been examined. Such figures have been compared with previous results obtained for the equivalent unprocessed phosphate
rocks.
In general the effects of additives on the solubility of the phosphate rock residues were similar to those found for unprocessed
phosphate rocks. However, the solubility figures were considerably lower for the 20% acidulated residues, while 2% formic
acid solubilities for the 35% acidulated residues were also reduced. This would indicate that some deactivation of the phosphate
rock had taken place during acidulation, the degree of which was dependent on the acidulation level and could be more readily
observed in changes in 2% formic acid solubility than in 2% citric acid figures. 相似文献
20.
This paper investigates the effect of interactions between the Walsh codes and data sequences on the statistical moments of the forward-link CDMA signal. Of primary interest is the normalized fourth-order moment, which is referred to as the “power variance”. Several techniques for reducing the power variance of the CDMA signal are discussed that are based on Walsh code selection and data encoding. Certain groupings of Walsh codes, referred to as “active quadruples”, are shown to be useful in predicting the potential of each technique. Results demonstrate the reduction in the power variance afforded by two novel approaches referred to as “channel hopping” and “data reversal” 相似文献