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91.
G. E. Selyutin V. A. Voroshilov Yu. Yu. Gavrilov V. A. Poluboyarov Z. A. Korotaeva V. A. Zakharov V. E. Nikitin 《Theoretical Foundations of Chemical Engineering》2010,44(4):521-524
The object of investigation is superhigh-molecular-weght polyethylene (SMWP) with a molecular weight of up to 8 × 106 g/mole and a particle size from 63 to 315 μm obtained by the technique developed at the Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. The purpose of this work is to create structural polymer materials with high physical and technical characteristics and to extend the scope of the application of this polymer in industry. The problem is solved by the modification of SMWP powder particles via the introduction of nanodispersed ceramic materials. Based on the data obtained, the methods of the production of the article samples from nanocomposite materials based on SMWP via the hot-pressing technique were developed and the influence of the nanomodifiers on the properties of the composite material was studied. 相似文献
92.
NEDJOUA CHEGHIB MOHAMED ABDAOUI THIERRY CRESTEIL GENEVIÈVE AUBERT JEAN-LOUIS KRAUS 《Polycyclic Aromatic Compounds》2013,33(3):143-153
Through the coupling of substituted benzaldehydes with 8-hydroxy 5-amino methyl quinoline scaffold, a series of new derivatives has been synthesized. In vitro growth inhibitory effects on cancer cell line model have been evaluated. Discussion on the chemical reactivity of these new polycyclic aromatic analogs to generate alkylating species led to the hypothesis that the presence of an imine moiety impedes the formation of quinone methide intermediate and consequently abolishes in part their antiproliferative activity. 相似文献
93.
V. I. Zakharov V. A. Matveev D. V. Maiorov A. R. Alishkin 《Glass Physics and Chemistry》2011,37(6):619-623
This paper reports on the results of investigations into the development of the methods employed for acid treatment of nepheline and the search for new directions in the use of products obtained in the nepheline processing, which have made it possible to design and implement technologies for producing the aluminum-silicon coagulant/flocculant for water purification, as well as technologies for fabrication and application of nepheline-based silicon-containing thickening agents intended for the simplest water-containing explosives of the “Akvatol” type and others. 相似文献
94.
MS Cookson PC Sogani P Russo J Sheinfeld H Herr G Dalbagni VE Reuter CB Begg WR Fair 《Canadian Metallurgical Quarterly》1997,79(3):432-438
OBJECTIVES: To assess the pathological staging and biochemical progression-free survival (assessed using serum prostate-specific antigen level) of patients with clinically localized prostate cancer using neoadjuvant androgen deprivation therapy (ADT) in combination with radical retropubic prostatectomy (RRP). PATIENTS AND METHODS: A prospective study was carried out on 69 patients with localized prostate cancer who were enrolled in a trial of 3 months of ADT followed by RRP (group 1). These patients were compared with 72 patients matched for age and clinical stage who declined ADT therapy and had RRP concurrently (group 2). Assignment to the individual treatment groups was thus determined by the patient's preference and not the physician's selection. Pathological staging and biochemical progression-free recurrence were compared between the groups. RESULTS: The rate of organ-confined (pT2) tumours was 74% in group 1 and 49% in group 2 (P < 0.01), and the rate of margin-negative tumours was 87% in group 1 and 64% in group 2 (P < 0.01). Within a median follow-up of 35 months, there was no significant difference in biochemical failure between the groups (P = 0.37). Patients with pT2 disease, regardless of treatment, had similar biochemical failure rates. In the patients with margin-positive disease, there was a significantly higher biochemical failure rate in group 1 (P = 0.02). CONCLUSIONS: The rates of organ- and specimen-confined disease were higher among the patients treated with ADT. The preliminary follow-up suggested that patients with pT2 disease after ADT have a biochemical progression-free recurrence rate similar to pT2 patients treated with RRP alone. Additionally, high biochemical failure rates in patients with margin-positive disease after ADT may identify a subset of more biologically aggressive tumours in need of early adjuvant treatment. 相似文献
95.
I. A. Zakharov 《Glass and Ceramics》1998,55(9-10):292-294
Technology for production of glass laminate based on aluminophosphate binder involving pressure molding of previously dried glass fabric pieces with a deposited suspension of the powder filler in the binder (prepreg) allows for a considerable decrease in consumption of the initial components and significantly improves the mechanical strength of the material. The possibility of using crushed clippings and chips of glass laminate as a powder filler is demonstrated. 相似文献
96.
The mechanical properties of totally ischemic hearts of inbred albino rats were studied. The ischemic myocardium was found to be more sensitive to cyclic loads. Energy deficient contracture of cardiomyocytes is a factor which increases the resistance of the myocardium to mechanical effects. 相似文献
97.
R Poon P Lecavalier P Chan C Viau H H?kansson I Chu VE Valli 《Canadian Metallurgical Quarterly》1995,15(6):455-463
Groups of ten male and female weanling Sprague-Dawley rats were fed diet containing 0, 5, 50, 500 or 5000 ppm of a medium-chain chlorinated paraffin (C14-17, 52% chlorination) for a period of 13 weeks. Increased relative liver weight was observed at 500 and 5000 ppm in females and at 5000 ppm in males. Relative kidney weight was increased at 5000 ppm in both sexes. Serum cholesterol was increased in the females in a dose-related manner starting at 50 ppm. At 5000 ppm, animals of both sexes had elevated hepatic UDP-glucuronosyltransferase activity while only females showed increased aminopyrine N-demethylase activity. Increased urinary N-acetylglucosaminidase activity occurred at 5000 ppm in females. Increased urinary ascorbic acid excretion monitored at week 12 and a decreased hepatic vitamin A level were detected in females receiving the 500 ppm diet and male and female rats at 5000 ppm. Mild, adaptive histopathological changes were detected in the liver of rats of both sexes at 500 and 5000 ppm, and in the thyroid of males and females starting at 500 and 50 ppm respectively. Minimal changes were observed in the kidney proximal tubules of male rats fed the 5000 ppm diet and in the inner medulla tubules of female rats fed the 500 and 5000 ppm diets. These data indicate that the medium-chain chlorinated paraffin produces biochemical and histological changes at dietary levels of greater than or = 50 ppm in females and greater than or = 500 ppm in males. 相似文献
98.
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100.
Günther Brauner ÖVE 《e & i Elektrotechnik und Informationstechnik》2000,117(7-8):447-447