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121.
The broad‐line 1H‐NMR study of the polymer blend composed of isotactic polypropylene and ethylene–propylene–diene monomer rubber was carried out. The NMR measurements were performed on the samples of the polymer blend and on the components of the blend in the temperature range covering the glass‐transition regions of all studied polymers. Conclusions were drawn from the temperature dependencies of the second moment M2 and of the data obtained by the decomposition of the spectra into the components related to the motionally distinct regions of the partially crystalline polymer. The mass fractions of the amorphous, intermediate, and crystalline domains and the widths of the spectra related to the particular phases were computed from the spectra. A double glass transition was revealed for the polymer blend. Different mechanisms of the motional processes related to the glass transition were deduced from the data. The gradual increase of the number of the chains and the enhancement of the chain mobility within noncrystalline regions of the polymer blend are responsible for the motion related to the lower glass transition and only transformation of the hindered motion into free motion was found in the temperature region of the upper glass transition. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 247–252, 2004 相似文献
122.
Several recent papers have documented observations of the "psychic" salivary secretion (a fortuitously conditioned reflex)--some as early as 1840--which preceded Pavlov's classical experiments in 1902. This note calls attention to Regnier De Graaf who utilized a "psychic" salivary secretion of a fistulated dog, and reported his findings in a publication dated December 17, 1664. De Graaf's drawing of his fistulated dog is argued to be one of the most interesting documents in the history of psychology, for it has a striking similarity to the numerous drawings of Pavlov's dog made more than 250 years later. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
Towards a global historical emission inventory for selected PCB congeners--a mass balance approach. 2. Emissions 总被引:2,自引:0,他引:2
Accurate and complete data on the global atmospheric releases (emissions) of individual PCB congeners are essential to study source-receptor relationships and contamination patterns in remote areas, such as the Arctic. Information on the anthropogenic emissions may also be useful for the interpretation of measured levels and patterns of atmospheric PCBs. This study builds upon an accompanying paper, presenting an estimate of the global historical production and consumption of 22 PCB congeners (Breivik K, Sweetman A, Pacyna JM, Jones KC. Towards a global historical emission inventory for selected PCB congeners--a mass balance approach. 1. Global production and consumption. Sci Total Environ, submitted). Here, a dynamic mass balance model is elaborated, parameterised and applied in an attempt to estimate the historical anthropogenic emissions as a direct result of the widespread usage of PCBs for a period of 70 years. This paper presents details of the mass balance approach, along with a discussion of the major uncertainties. It is shown that the diversity of historical usage, disposal and accidental release pathways makes it an extremely difficult task to bridge the gap between consumption and emissions, resulting in an equally complex and diverse true emission pattern. These results may therefore at best represent order-of-magnitude estimates only and the results in absolute terms should be treated with great caution. In spite of these uncertainties, useful information can still be gained. The results suggest that temperature is an extremely important factor controlling both emission amount as well as the emission pattern of PCBs. In particular, the emissions of the more chlorinated (and persistent) PCB congeners appear to be significantly influenced by (uncontrolled) high-temperature sources. As a consequence, it may prove warranted to undertake further measures to avoid that contaminated materials are subject to elevated temperatures and uncontrolled burning. It is furthermore suggested that efforts should be directed towards a better characterisation and quantification of these potentially important release pathways. In addition, alternative approaches to bridge the gap between consumption and emissions in quantitative terms should be considered in order to improve these estimates. 相似文献
124.
Katarína Lendelová Jozefí na Petrovičová 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2006,10(7):564-566
A probability theory on IF-events has been constructed by Grzegorzewski and Mrówka in [2] and axiomatically characterized
by B. Riečan in [6]. More general situation was studied by B. Riečan in [5]. He introduced the IF-probability, which is decomposed
onto two probabilities on Lukasiewicz tribe. The aim of this paper is to define the IF-probability and IF-observable on MV-algebras.
We show that some known results of [7] can be applied also for these IF-events. 相似文献
125.
We present a novel tool for reverse engineering of modeling histories from consecutive 3D files based on a timeline abstraction. Although a timeline interface is commonly used in 3D modeling packages for animations, it has not been used on geometry manipulation before. Unlike previous visualization methods that require instrumentation of editing software, our approach does not rely on pre‐recorded editing instructions. Instead, each stand‐alone 3D file is treated as a keyframe of a construction flow from which the editing provenance is reverse engineered. We evaluate this tool on six complex 3D sequences created in a variety of modeling tools by different professional artists and conclude that it provides useful means of visualizing and understanding the editing history. A comparative user study suggests the tool is well suited for this purpose. 相似文献
126.
The aim of the submitted work is to study the influence of applied loads ranging from 0.09807 to 0.9807 N on microhardness. Whereas standard reference block with defined specified hardness and its uncertainty was used as a specimen, individual measurement involved indirect calibration of tester. The measurement was repeated for estimation of the variability of results. The influence of applied load on the measured value of microhardness was evaluated by Meyer’s index n, PSR method and by analysis of variance and was different for individual “measurements” despite the identical specimen, method, equipment and appraiser. The uncertainty of measured values of the hardness partly obscures the occurrence and type of indentation size effect. 相似文献
127.
Dawid Rys Jozef Judycki Piotr Jaskula 《International Journal of Pavement Engineering》2016,17(8):716-726
Overloaded vehicles have a significant impact on pavement fatigue life and distress. As the studies show, the phenomena intensify when the control of traffic is poor. The paper presents the results of the research including analysis of weigh in motion data from eight stations and analysis of asphalt pavement fatigue caused by mixed traffic. Distributions of vehicles axles load including the multiple axles effects are presented. Mixed axle loads were transformed into equivalent number of standard 100 kN axle loads. The regression model of load equivalency factor depending on the axle load distribution and the percentage of overloaded vehicles is presented. The analysis of the effect of overloaded vehicles on decrease of fatigue life of a pavement structure is presented. The analysis has shown that the increase of percentage of overloaded vehicles from 0% to 20% can reduce the fatigue life of asphalt pavement upto 50%. 相似文献
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