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91.
O. A. Dolgopolov 《Glass and Ceramics》2005,62(5-6):155-156
Magnetic roll separators on rare-earth magnets are suitable for removing iron impurities from various materials. The advantages
of these magnetic separators over traditional ones are demonstrated.
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Translated from Steklo i Keramika, No. 5, p. 33, May, 2005. 相似文献
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O Prez‐Camacho S Sepúlveda‐Guzmn M Prez‐lvarez M García‐Zamora G Cadenas‐Pliego 《Polymer International》2005,54(12):1626-1631
New functionalized styrene–maleimide copolymers were prepared by free radical copolymerization of styrene (St) and N‐4‐carboxybutylmaleimide (NBMI) in chloroform, using 2,2′‐azobisisobutyronitrile (AIBN) as initiator. Monomer and copolymer characterization was carried out by 1H‐ and 13C‐NMR. Copolymer composition was determined by elemental analysis and Fourier‐transform infrared (FTIR) spectroscopy. The glass transition temperature (from DSC) and the thermogravimetric analysis (TGA) of the copolymers were consistent with the thermal behavior and stability observed for alternating St–maleimide copolymers. St–NBMI copolymers crosslinked with divinylbenzene (DVB) were also synthesized and their cation exchange properties evaluated in order to assess the capacity of the new copolymers to bind metallic ions. Copyright © 2005 Society of Chemical Industry 相似文献
94.
In this paper, we argue that successful integration of knowledge across work domains in the short-term can mask the generation of long-term consequences. We explore a setting, the introduction of environmental considerations into semiconductor manufacturing, where the eventual adoption of common measurement artifacts and associated practices enabled knowledge integration, but failed to address significant underlying consequences. Drawing from observational, interview, and archival data we develop an understanding of the work practices of the Tech and EnviroTech groups as structured by the material world and broader collective conventions. We introduce the concept of knowledge regime to outline the differences in knowledge across these work domains. More specifically, we find that differences in the causal specificity and developmental time horizon of knowledge and the measurement artifacts that result contribute to the relative power of one knowledge regime over another. Understanding these sources of incompatibility provides insight into the design requirements of information systems as boundary objects for knowledge integration, but also specifies the potential limits to any design effort. 相似文献
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O Ukkola MJ Savolainen PI Salmela K von Dickhoff T Kiema YA Kes?niemi 《Canadian Metallurgical Quarterly》1995,73(6):307-311
In the search for new risk factors for diabetic macroangiopathy the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme gene was studied in 237 consecutive patients (125 men and 112 women) with non-insulin-dependent diabetes. The female population showed an excess of ischemic electrocardiographic changes or definite myocardial infarctions in the patients homozygous for the deletion [D/D; odds ratio (OR) 2.8; 95% confidence interval (CI) 1.4-5.3] and in the insertion/deletion heterozygotes (I/D; OR 1.8; CI 1.1-3.1) compared with the patients homozygous for the insertion (I/I). In the total series coronary heart disease, cerebrovascular disease, and claudication were more often observed in the patients with I/D (OR 1.5; CI 1.0-2.2) or the D/D genotype patients (OR 1.7; CI 1.1-2.6) than in those with the genotype I/I. The systolic blood pressure was lower in patients with genotype I/I (138 +/- 19 mmHg) than in those with the genotype I/D (149 +/- 22 mmHg) or D/D (150 +/- 21 mmHg; P < 0.02). The prevalence of hypertension and the median urinary albumin excretion rate also tended to be lowest in the I/I genotype patients. Multiple logistic analysis revealed that in women the angiotensin-converting enzyme D/D genotype is independently associated with coronary heart disease. Our findings suggest that variation at the angiotensin-converting enzyme gene locus is one of the factors involved in the predisposition of diabetic patients to the development of arterial disease and hypertension. 相似文献
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