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101.
Blends of medium-volatile or high-volatile coals have been carbonized in a 7 kg oven with low-volatile coals (6–16% VM, dmmf). A comparison is made of the strength and structural properties of these cokes with those of the cokes made under corresponding conditions from the medium or high-volatile coals alone. With increasing levels of addition of the low-volatile coals the tensile strength of the blend cokes generally attains a maximum and then decreases. These strength changes are related to changes in porosity, pore-wall thickness and pore dimensions. Coals which display some degree of plasticity and which are weakly caking improve coke quality by altering the pore-structure due to the combined effects of decreasing the pore diameter and slightly increasing the wall thickness. Those additives which are non-caking act primarily as wall thickeners.  相似文献   
102.
103.
Evaluated the effects of manipulated cognitive expectancy on avoidance behavior in an experimental paradigm that simulated systematic desensitization. 72 female undergraduates with moderate fear of spiders were divided among 4 expectancy conditions ranging from a set to improve to a set that fear would increase. 2 measures of electrodermal activity were continuously recorded while the Ss, who relaxed in a reclining chair, were exposed to a preserved tarantula. Results indicate that both overt avoidance behavior and 2 verbal indexes were differentially affected by expectancy and that no relationship between avoidance behavior and autonomic reactivity was evident. It is concluded that the processes which mediate systematic desensitization can not adequately be explained by the counterconditioning model alone. (34 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
Atomic absorption spectroscopy is being used as a routein method to determine sodium, potassium, calcium, magnesium, copper and many other metallic elements in oils, fats, milk and other substances. Copper and iron can be measured directly in milk without sample preparation. When highly acidified samples are run, a new plastic-lined nebulizer is useful to prevent spurious results due to corrosion. A new sampling device, the Graphite Furnace, can analyze extremely small samples and gives detection limits in the picogram (10−12 g) range. One of 28 papers presented at the Symposium, “Metal-Catalyzed Lipid Oxidation,” ISF-AOCS World Congress, Chicago, September 1970.  相似文献   
105.
In the scintillation mechanism for alkali iodides doped with thallous iodide: 1. Most of the luminescence, and possibly all of it, is from recombination and therefore energy transfer is predominantly from charge transport to thallium. 2. There are two modes of recombination at thallium which differ in the sequence of charge trapping at Tl+. The electron may be trapped before a mobile hole recombines with it, or the hole may be trapped before recombination with a free electron. 3. Thermal hole diffusion is an important process at room temperature and determines which mode a recombination event follows. 4. Both modes of recombination are active. 5. There is non-thermal hole trapping which is a significant part of the scintillator mechanism.  相似文献   
106.
Analyzed random input data with J. B. Kruskal's nonmetric scaling program in order to establish null hypotheses for the goodness-of-fit measure. Various numbers of hypothetical stimuli were analyzed using the Euclidean distance metric in various dimensionalities, and the effects of tied ranks were studied. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
108.
The direct Finite Element Analysis which was successfully employed in the solution of dynamic flexural traveling wave problems is extended herein to provide the transient behaviour of finite beams and plates in which shear deformation and rotatory inertia are considered. The particle and angular velocities are exponentially damped so that the static solutions for these problems are obtained with the same analysis which provided the dynamic and transient cases. Three special cases are chosen as examples. In the first, a sinusoidally varying shear force is applied at the tip of a cantilever beam. The resonant characteristics of this beam for both the undamped and damped cases are studied. In the second, a step shear loading is applied to a cantilever beam and its damped dynamic history is studied. Finally, a circular plate whose outer edge is simply supported is impacted at its inner edge by a step moment and its damped transient behaviour is determined. The idea of the methods is potentially applicable to dynamic problems in general.  相似文献   
109.
Phenanthrene-formaldehyde resins of different oxygen content were reacted with phenol 110°C in the presence of a strong acid catalyst. Cleavage occurred at the dimethylene ether and acetal bridges joining the aromatic nuclei with the concomitant formation of phenanthrene-formaldehyde-phenol resins. These resins were characterised by gel permeation chromatography, 1H n.m.r. and infrared spectroscopy.  相似文献   
110.
Ermittlung der Diffusionskoeffizienten von Silizium in flüssigen Schlacken in Abhängigkeit vom Kalk-Kieselsäure-Verhältnis und vom Tonerdegehalt für 15 bis 60% SiO2 und 15 bis 40% Al2O3 in der Schlacke und Temperaturen von 1500 bis 1600°C. Aus der Aktivierungsenergie der Diffusion Rückschlüsse auf den Aufbau der Schlacken und auf den Diffusionsmechanismus. Aussagen zum Einfluβ von Kalk und Tonerde auf die Beständigkeit des Kieselsäuregitters. Vergleich der Diffusionskoeffizienten von Silizium und Kalzium in der flüssigen Schlacke.  相似文献   
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