We study experimentally the slow growth of a single crack inpolycarbonate films submitted to uniaxial and constant imposedstress. The specificity of fracture in polycarbonate films is theappearance of flame-shaped macroscopic process zones at the tipsof the crack. Supported by an experimental study of the mechanicalproperties of polycarbonate films, an analysis of the stressdependence of the mean ratio between the process zone and cracklengths, during the crack growth, shows a quantitative agreementwith the Dugdale-Barenblatt model of the plastic process zone. Wefind that the fracture growth curves obey strong scalingproperties that lead to a well-defined growth master curve.
CRACK Steinberg V-STACKl
According to pharmacologists, the major differences are how the drug is administered and its effects on the user. Although it can be injected, powder cocaine is usually snorted, while crack cocaine can only be smoked. When cocaine is injected or smoked, the drug takes effect more quickly, resulting in a more intense high of shorter duration.REF For this reason, as well as the fact that crack cocaine is much cheaper than powder cocaine, many believe that crack cocaine users are more likely to become addicted than powder cocaine users are. Moreover, while some believe that crack users are more prone to violent reactions than powder cocaine users are, others dispute this.REF
Additionally, regardless of the intent behind these laws, as has been pointed out many times, it is clear that the largest impact, both in terms of the devastation that drugs have wrought and in terms of the imposition of extremely long sentences on offenders, has been felt most keenly in communities of color.REF I further note that the vast majority of states do not treat crack cocaine any differently from powder cocaine in terms of sentencingREF and that this bill has attracted bipartisan supportREF as well as support from major prosecutorial and law enforcement organizations.REF While I do not have a settled view on whether it makes sense to completely eliminate the differential when it comes to sentencing, the current disparity between how crack cocaine offenders are treated compared to powder cocaine offenders does strike me as being excessive.
Good Housekeeping, May 1964, p. 62: 'One crisis occurred in 1937 when, after a period of intense work in the store, Barry suffered a nervous breakdown. After a lengthy rest, he went back to work. But two years later, when he went to Prescott, Arizona, to help open a new branch of the store, and spent five days and nights without sleep, he cracked again. 'His nerves broke completely,' says Mrs. Goldwater. 'He couldn't sleep nights. He was very nervous. I immediately said we were going to get away to Honolulu. He was seasick all the way. But then he relaxed on the beach and just rested.' The change of pace was, apparently, all he needed.' 2ff7e9595c
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