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11.
N‐p‐Bromophenylmaleimide (BrPMI) does not polymerize in solution by conventional free radical mechanism. However, it readily polymerized in bulk when mixed with a free radical initiator and heated in a microwave oven for 7–8 min. Copolymerization of ethyl methacrylate or butyl methacrylate with BrPMI was conducted in dioxane. The copolymers were characterized by IR and 1H NMR spectroscopy and gel permeation chromatography. The monomer reactivity ratios were calculated by a non‐linear least‐square analysis. Thermal analysis indicated a great improvement in thermal stability of the copolymers compared with the methacrylate homopolymers. BrPMI was also polymerized in bulk in the DSC pan, which allowed the calculation of the activation energy of its polymerization. Copyright © 2003 Society of Chemical Industry 相似文献
12.
R Albrecht TC Awes C Baktash P Beckmann F Berger R Bock G Claesson G Clewing L Dragon A Eklund RL Ferguson A Franz S Garpman R Glasow HA Gustafsson HH Gutbrod J Idh P Jacobs K Kampert BW Kolb P Kristiansson IY Lee H Loehner I Lund FE Obenshain A Oskarsson I Otterlund T Peitzmann S Persson F Plasil AM Poskanzer M Purschke H Ritter S Saini R Santo HR Schmidt T Siemiarczuk SP Sorensen E Stenlund ML Tincknell GR Young 《Canadian Metallurgical Quarterly》1991,44(6):2736-2752
13.
D. B. Zeik J. R. Dugan D. W. Schroeder J. W. Baur S. J. Clarson G. N. De Brabander J. T. Boyd 《应用聚合物科学杂志》1995,56(9):1039-1044
Plasma-polymerized hexamethyldisiloxane (HMDS) films have been prepared as both planar and channel wave guides. The optical attenuation results measured in both the planar and channel HMDS wave guides were found to be similar, thus demonstrating that the inherent solvent resistance and chemical inertness of the plasma polymerized films allows the use of common photoresist techniques, including application of the photoresist, photomasking, and subsequent etching. This may be contrasted with wave guides made from conventional polymers, where careful consideration must be given to photoresist/polymer compatibility, because the photoresist solvents may adversely affect the underlying polymer and lead to degradation of the material during processing. © 1995 John Wiley & Sons, Inc. 相似文献
14.
GR McKee 《Canadian Metallurgical Quarterly》1995,76(2):427-434
Legal responsibility for acts presumes that a person's behavior is rationally intentional and under voluntary control. Automatism, a type of insanity defense, contends that the person's conscious, voluntary control of behavior has been impaired by a mental disorder. In a recent case in South Carolina, automatism was offered as a defense to adultery, an at-fault grounds to divorce. On appeal, the State Supreme Court recognized the novel application of mental impairment defenses in domestic litigation and remanded the case for rehearing. Implications of the ruling for clinical and forensic practice in family court are discussed. 相似文献
15.
Saksenaea vasiformis, a zygomycete belonging to the order Mucorales, is a rare cause of zygomycosis with 17 cases documented world-wide. It usually infects the immunocompromised or traumatized and has a high mortality rate. Because of its failure to sporulate under normal laboratory conditions it may be difficult to identify. We describe here an unusual case report of Saksenaea vasiformis with sporulation and identification within a week using a modified sporulation technique. 相似文献
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Prednisolone therapy of idiopathic feline lower urinary tract disease: a double-blind clinical study
CA Osborne JM Kruger JP Lulich GR Johnston DJ Polzin LK Ulrich J Sanna 《Canadian Metallurgical Quarterly》1996,26(3):563-569
A double-blind clinical study was performed to evaluate prednisolone as treatment for idiopathic feline lower urinary tract disease. No differences in response were observed in prednisolone- and placebo-treated cats. 相似文献
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The review examines the evidence that the supply of cholesterol available for incorporation into nascent lipoprotein particles exerts a regulatory influence on apolipoprotein (apo) B secretion by the liver. Support for this hypothesis comes both from in vitro experiments and from recent observations in normal subjects and patients with dyslipidemia associated with familial hypercholesterolemia, obesity, noninsulin dependent diabetes mellitus, growth hormone deficiency and cholesteryl ester storage disease. The findings do not negate a role for triglyceride synthesis in determining apoB secretion in very low density lipoprotein, but the inhibitory effects on the latter process of pharmacological blockade of cholesterol synthesis or esterification suggest that it is conditional upon an adequate supply of cholesteryl ester. 相似文献
20.
The processing endoribonuclease RNase E (Rne), which is encoded by the rne gene, is involved in the maturation process of messenger RNAs and a ribosomal RNA. A number of deletions were constructed in order to assess functional domains of the rne gene product. The expression of the deletion constructs using a T7 promoter/RNA polymerase overproduction system led to the synthesis of truncated Rne polypeptides. The smallest gene fragment in this collection that was able to complement a temperature sensitive rnets mutation and to restore the processing of 9 S RNA was a 2.3-kilobase pair fragment with a 1.9-kilobase pair N-terminal coding sequence that mediated synthesis of a 70.8-kDa polypeptide. Antibodies raised against a truncated 110-kDa polypeptide cross-reacted with the intact rne gene product and with all of the shorter C-terminal truncated polypeptides, indicating that the N-terminal part of the molecule contained strong antigenic determinants. Furthermore, by analyzing the Rne protein and the truncated polypeptides for their ability to bind substrate RNAs, we were able to demonstrate that the central part of the Rne molecule encodes an RNA binding region. Binding to substrate RNAs correlated with the endonucleolytic activity. RNAs that are not substrates for RNase E did not bind to the protein. The two mutated Rne polypeptides expressed from the cloned gene containing either the rne-3071 or ams1 mutation also had the ability to bind 9 S RNA, while their enzymatic function was completely abolished. The data presented here suggest that the endonucleolytic activity is encoded by the N-terminal part of the Rne protein molecule and that the central part of it possesses RNA binding activity. 相似文献