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71.
Fine grained carbon-bonded Al2O3–C materials as used in ceramic filters have been manufactured by uniaxial and isostatic pressing, respectively. The variation in the microstructure over the cross section of the samples which in particular depends on the shaping technique plays an important role in the wetting of the material by liquid steel. Moreover, the amount and grain size of the binder has a decisive influence on the porosity and bulk density and therefore on the mechanical properties. For this, two different grain size distributions of Carbores® P binder were used, and in addition the fraction of binder was varied from 5–30 wt%. Tests of the cold crushing strength and of the cold modulus of rupture were performed at room temperature. The adjusted bulk density, open porosity and shrinkage of the samples were determined and the microstructure was analyzed by means of scanning electron microscopy. For control of a homogeneous distribution of carbon in the samples, the residual carbon content was measured also within individual samples at different positions. 相似文献
73.
Junfeng Chen Nan Li Jana Hubálková C.G. Aneziris 《Journal of the European Ceramic Society》2018,38(9):3387-3394
Different approaches to develop low-carbon refractories have been recently proposed. Among them, the use of Ti3AlC2 can influence the corroded interface and improve the corrosion resistance of low-carbon containing refractories, but current understanding of the role of Ti3AlC2 is far from complete. In this work, the impact of the single additives Ti3AlC2 and Si as well as their combination on the microstructure and properties of MgO-C refractories were evaluated. The newly formed ceramic bonding phases contribute to superior mechanical properties. However, the high volume expansion of Ti3AlC2 led to adverse effect when using Ti3AlC2 as single antioxidant. The combination of Ti3AlC2 and Si could inhibit the rapid oxidation and excessive expansion of Ti3AlC2. 相似文献
74.
P210 BCR/ABL is a chimeric oncogene implicated in the pathogenesis of chronic myelogenous leukemia. BCR sequences have been shown to be required for activation of the tyrosine kinase and transforming functions of BCR/ABL. In this work, we show that two other structural requirements for full transforming activity of P210 BCR/ABL include a functional tyrosine kinase and the presence of tyrosine 1294, a site of autophosphorylation within the tyrosine kinase domain. Replacement of tyrosine 1294 with phenylalanine (1294F) greatly diminishes the transforming activity of BCR/ABL without affecting the specific activity of the protein tyrosine kinase. Expression of an exogenous myc gene in fibroblasts partially complements the transforming capacity of mutant P210 BCR/ABL (1294F). Surprisingly, tyrosine 1294 is not required for efficient induction of growth factor-independence in hematopoietic cell lines by P210 BCR/ABL. These results suggest that autophosphorylation at tyrosine 1294 may be important for recognition and phosphorylation of cellular substrates in the pathway of transformation, but it is not critical for mediating the events which lead to growth factor independence. 相似文献
75.
VA Boiadzhian NN Gavrilova ON Gaenko VA Medik VV Podchalimova VS Rybakov VO Shchepin 《Canadian Metallurgical Quarterly》1995,(6):46-50
Comparative study of hospital activities in the Novgorod district and nine countries of the European Community, carried out within the framework of the International Project CAMISE (Case Mix and Severity) of the European Community on the basis of the classification system for diagnosis-related groups, showed a lower Case Mix Index, a longer hospital stay for all major disease, and a lower surgical activity in the hospitals of the Novgorod district in comparison with other European countries. The detected differences are largely due to specific features in the organization of hospital service in Russia (no special hospitals for acute and chronic patients, no nursing homes) and insufficiently intensive therapeutic and diagnostic process. 相似文献
76.
77.
NG Kan VG Petrosian IA Martirosian AP Ryskov IS Darevski? FD Danielian DM Riabinin VV Grechko ON Tokarskaia 《Canadian Metallurgical Quarterly》1998,32(5):805-812
We performed a lateral approach for the release of post-traumatic stiffness of the elbow in 22 patients using a modified technique designed to spare the lateral ligaments. They were reviewed after a mean interval of 26 months. The total humeroulnar joint movement had increased from a mean of 74 degrees to 129 degrees and forearm rotation from a mean of 135 degrees to 159 degrees. Both pain and function in the elbow had improved significantly. This modified lateral approach allows release of post-traumatic contracture without disruption of the lateral collateral ligament or the origins of the extensor tendon at the lateral epicondyle of the humerus. The advantages include a simplified surgical procedure, less operative morbidity, and unrestricted rehabilitation. 相似文献
78.
79.
SO Ogunniyi ON Makinde AE Adeniyi YO Sanusi OO Lawal 《Canadian Metallurgical Quarterly》1998,28(4):239-240
A case of advanced extrauterine pregnancy involving the rectum and with passage of fetal limb through the anus is presented. The patient probably had a heterotopic gestation. 相似文献
80.
R D'Agostino ON Nwasokwa A Moschetto J Spivak BS Schneider 《Canadian Metallurgical Quarterly》1995,108(6):1514-1519
Since there is experimental evidence that insulin promotes atherosclerosis, we tested the hypothesis that insulin levels are higher in patients with diffuse atherosclerotic coronary artery disease by measuring insulin levels in 46 nondiabetic patients with angiographically defined diffuse coronary artery disease and 46 normal controls with angiographically normal coronary arteries. Fasting insulin levels were similar in both groups of patients: 7.70 +/- 5.77 microU/mL in those with diffuse coronary disease versus 7.39 +/- 5.01 microU/mL in controls. Also, insulin levels drawn 1 and 2 h after oral glucose challenge were not significantly different in patients with diffuse disease (48.78 +/- 32.46 microU/mL and 42.26 +/- 32.38 microU/mL, respectively) compared with patients with normal coronary arteries (51.03 +/- 28.01 microU/mL and 43.79 +/- 31.62 microU/mL, respectively). We conclude that insulin probably does not promote clinical atherosclerosis in nondiabetics. 相似文献