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A. Phillion H. W. Zurob C. R. Hutchinson H. Guo D. V. Malakhov J. Nakano G. R. Purdy 《Metallurgical and Materials Transactions A》2004,35(4):1237-1242
We have evaluated controlled decarburization as a method for probing the effect of alloying elements on ferrite growth from
austenite. The technique permits the exploration of longer-time ferrite layer growth; it minimizes the effects of interface
structure on ferrite growth; and it permits the isolation of the effects of temperature and alloying element concentration
on ferrite/austenite interface motion. The study of the decarburization of initially homogeneous Fe-C-Ni alloys was complemented
by experiments using specimens with a controlled nickel concentration gradient. Although the decarburization method yields
consistent results at longer times, it is found to be less appropriate for the study of initial ferrite growth. Nucleation
in the gas/solid interface region, coupled with uncertainties about the precise time of decarburization, leads to large relative
errors at the earliest times. For these reasons, the method is considered a valuable complement to studies based on precipitation
boundary conditions.
This article is based on a presentation given in the symposium “The Effects of Alloying Elements on the Gamma to Alpha Transformation
in Steels,” October 6, 2002, at the TMS Fall Meeting in Columbus, Ohio, under the auspices of the McMaster Centre for Steel
Research and the TMS-ASM Phase Transformations Committee. 相似文献
3.
A Notghi R Hutchinson D Kumar NB Smith LK Harding 《Canadian Metallurgical Quarterly》1994,35(7):976-981
Segmental colonic transit has been measured in 101 patients. Two MBq of 111Indium absorbed on resin pellets and encapsulated in an enteric coated capsule was given at 7 00 am. Hourly images during the first day, and three images during each subsequent day were acquired for up to three days. Using all scan and patient data the scans were categorised in one of the five patterns of colonic transit: normal, rapid, right delay, left delay, or generalised delay. The geometric centres and per cent activity at each time point was compared between the five groups of colonic transit patients to find the best time for imaging and so to distinguish the five groups. During the first day, early images did not help in diagnosis of patterns of transit, however, in the later images (six hours onwards after the ingestion of the activity) the rapid transit groups could be identified. Images at 27 and 51 hours were both required to distinguish all five groups of patients from each other. Only in the 'normal' transit patients was there some excretion of the activity during the course of the second day, otherwise there was no difference in the images taken in the course of a day (second or third day). A simplified protocol requires a minimum of three images to distinguish all five patterns of colonic transit. The activity should be ingested in the morning (7 00 am) and the first image taken at the end of the working day (8-10 hours after ingestion), the second image on the morning of the second day, and the third image during the course of the third day. This simple protocol would provide all the clinically relevant information necessary for correct classification of the colonic transit. 相似文献
4.
Dentists are often called upon to perform painful procedures on children. This may present a management problem for the practitioner who is unfamiliar with accepted behavioural management techniques or prescribing analgesics for paediatric patients. This article will review techniques that may be used to guide a child patient's behaviour through painful procedures as well as addressing the need for post-operative analgesics in the paediatric population. 相似文献
5.
AG Labetskaia KM Kireenko IV Ba?dakova IM Tishechkina 《Canadian Metallurgical Quarterly》1997,31(5):391-396
The study of the micromammalian parasite complexes in the Belorussian part of the evacuation zone of the Chernobyl nuclear station revealed 13 species of Coccidia and 30 species of ectoparasitic Arthropoda. Total increase of abundance and biodiversity of both parasites and their hosts was observed. The part of ectoparasites being epidemically hazardous was significantly increased. An analysis of a long-term dynamics of parasite abundance reveals their adaptation to new conditions in the Belorussia. 相似文献
6.
IuP Spizhenko AV Biliaiev AM Zaremba IV Nahorny? AP Tkachenko 《Canadian Metallurgical Quarterly》1997,43(5-6):42-48
Investigated all links of oxygen homeostasis of patients in early period afterwards surgical stoppage gastro-intestinal bleeding and urgent intravascular volume replacement. Macrodelivery of oxygen (DO2) was reduced in two and more time in comparison with norm predominant in connection with anemia. In spite of the infringement of transport of oxygen through alveolar-capillary membrane (especially in patients with complications and death in early postoperative period), little affected of degree of hemoglobin saturation by oxygen. Despite decrease of erythrocyte zeta-potential, largely expressed in cases of lethal outcome, considerable infringement of passage through microcirculation vessels is fixed was not. The increase of degree of morbidity and anaerobic metabolism in early postoperative period was accompanied of hyperdynamic hemodynamic reaction. The increase of degree of morbidity was accompanied of increase oxygen deficit owing to infringement of oxidoreduction in fabries also. 相似文献
7.
VI Tselu?ko NA Kravchenko IV Shut' VI Cherkashina 《Canadian Metallurgical Quarterly》1994,28(5):73-77
Restriction fragment length polymorphism of the apo-B gene at the Xbal restriction site was detected. The association between RFLP of the apo-B gene and the level of lipid metabolism indices was revealed. The levels of total cholesterol LDLP CH and atherogenicity coefficient were significantly higher in homozygotes with this restriction site (X2X2) than in homozygotes X1X1 and heterozygotes. 相似文献
8.
IV Maslennikov AG Sobol J Anagli P James T Vorherr AS Arseniev E Carafoli 《Canadian Metallurgical Quarterly》1995,217(3):1200-1207
Phospholamban (PLN) is an intrinsic membrane protein of 52 amino acids which regulates the Ca2+ pump of the sarcoplasmic reticulum of heart, slow-twitch and smooth muscle (SR): it is normally assumed to exist in the membrane as a homopentamer. A monomeric analogue of phospholamban PLN(C41F), in which Cys41 was replaced by a Phe, was synthesized and its conformation studied by 1H NMR spectroscopy in a 1:1 mixture of chloroform/methanol. Most of the resonances in the 1H NMR spectra were assigned. The work has shown that the C-terminal hydrophobic portion forms a very stable alpha-helix. The hydrophilic N-terminal part adopts an alpha-helix configuration which is much less stable except for the stretch containing the phosphorylation sites. 相似文献
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