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71.
《Computers & Geosciences》2006,32(7):912-926
This paper describes the development of highly accurate adaptive discontinuous Galerkin schemes for the solution of the equations arising from a thin layer type model of debris flows. Such flows have wide applicability in the analysis of avalanches induced by many natural calamities, e.g. volcanoes, earthquakes, etc. These schemes are coupled with special parallel solution methodologies to produce a simulation tool capable of very high-order numerical accuracy. The methodology successfully replicates cold rock avalanches at Mount Rainier, Washington and hot volcanic particulate flows at Colima Volcano, Mexico. 相似文献
72.
73.
《Food Control》2006,17(8):676-679
In this study, the presence of Listeria spp. was investigated in a total of 157 raw milk and dairy product samples sold in Antakya (Antioch). The prevalence of Listeria spp. in raw milk and Turkish white cheese samples was found to be 2.12% and 8.23%, respectively. Listeria monocytogenes was not isolated from raw milk and found in only two cheese samples (2.35%). No Listeria spp. were isolated in any of the butter and yoghurt samples. 相似文献
74.
N Wassef G Sidhom Zakareya el-K Mohamed el-K 《Canadian Metallurgical Quarterly》1997,20(11):1693-1696
OBJECTIVE: To assess the level of serum lipoprotein(a) [Lp(a)] in nonobese and obese NIDDM subjects with android body distribution. RESEARCH DESIGN AND METHODS: Serum Lp(a) levels were measured in 30 long-standing NIDDM patients (duration of diabetes 12.5 +/- 3 years, mean +/- SD), with 15 of the patients being obese of android distribution (BMI > 30 kg/m2 and waist-to-hip ratio > 0.8). In addition, there were 15 android obese nondiabetic subjects and 10 healthy subjects serving as the control group. RESULTS: All groups of patients in this study (diabetic, obese, and obese diabetic) showed significantly higher levels of Lp(a) than the healthy control group. Lp(a) concentrations were significantly higher in NIDDM patients with android type of obesity than in nondiabetic androids (24.1 +/- 5.6 vs. 14.8 +/- 2.4 mg/dl, P < 0.001). Significantly greater levels of Lp(a) were found in nonobese subjects with diabetes when compared with obese subjects without diabetes (22.3 +/- 4.1 vs. 14.8 +/- 2.4 mg/dl, P < 0.001). Furthermore, Lp(a) serum concentrations were not dependent on the degree of glycemic control (controlled NIDDM 23.6 +/- 5.0 vs. uncontrolled NIDDM 21.4 +/- 2.7 mg/dl, NS), but were much greater in subjects with diabetes complicated by vascular disease (complicated 26.3 +/- 5.0 vs. uncomplicated 20.5 +/- 2.7 mg/dl, P < 0.001). No correlation was found between Lp(a) and other lipid parameters in this study. CONCLUSIONS: Lp(a) levels are significantly elevated in both android-obese and nonobese NIDDM patients regardless of the degree of glycemic control. Lp(a) is an independent risk factor showing greater elevations in those subjects complicated with diabetic vascular diseases. 相似文献
75.
B Ali-el-Dein A Nabeeh M el-Baz S Shamaa A Ashamallah 《Canadian Metallurgical Quarterly》1997,79(5):731-735
OBJECTIVE: To compare single-dose and multiple instillations of epirubicin in the chemoprophylaxis of superficial bladder tumours. PATIENTS AND METHODS: In a prospective randomized and controlled study, 168 evaluable patients were assigned to three groups after transurethral resection of bladder tumour (TURBT) and histological confirmation of its superficial nature (pTa and pT1). The groups were comparable for tumour stage, grade and other tumour characteristics. In group 1, patients received a single dose of 50 mg epirubicin in 50 mL normal saline immediately after TURBT; group 2 received 50 mg epirubicin in 50 mL normal saline 1-2 weeks after TURBT and the instillations were repeated for 8 weeks and thereafter monthly to complete one year of treatment: group 3 (control group) received no adjuvant therapy after TURBT. The patients were assessed by cysto-urethroscopy, urine cytology and DNA flow cytometry 8 weeks after resection and then every 3 months during the first 2 years and 6 monthly thereafter during the next 2 years. Intravenous urography was performed annually and when otherwise indicated. RESULTS: The recurrence rate was significantly lower in the patients treated with epirubicin than in the control group (24, 25 and 52%, respectively; P < 0.001). In those receiving epirubicin, the rates of recurrence were statistically comparable (P = 0.9). Patients who had a large tumour burden showed slightly lower recurrence rates with single-dose epirubicin than with delayed maintenance therapy but the difference was statistically insignificant. Patients with a history of bladder tumours before treatment had lower recurrence rates with maintenance treatment than with a single dose (34.6 and 22.6% in groups 1 and 2, respectively); again this difference was statistically insignificant. Patients with grade 3 tumours showed a marginal difference in favour of maintenance therapy. The rates of progression amongst the three groups were 5.5, 3.4 and 9.3%, respectively, with no significant differences. The overall toxicity rates were comparable in the two treated groups (22 and 25%). CONCLUSION: With the possible exception of grade 3 tumours, single-dose immediate epirubicin is as effective as delayed maintenance therapy, with the advantage of being more cost-effective. 相似文献
76.
I. Kashif H. Farouk S. A. Aly A. M. Sanad M. H. El-Kottamy E. E. Assem 《Journal of Materials Science: Materials in Electronics》1992,3(3):144-146
The effect of the addition of Fe2O3 and heat treatment duration on the magnetic susceptibility of vanadium borophosphate glass were studied. The magnetic susceptibility of glass samples was found to increase with increasing Fe2O3 content, which may be explained by the formation of the FeO6 group and the change of Fe2+ to Fe3+ which has higher paramagnetic properties. No detectable changes in the magnetic susceptibility with heat treatment for the samples containing 0.0, 0.5 and 1.0 mol% Fe2O3 was observed. The magnetic susceptibility for the heat treated samples containing 2.5, 5.0 and 7.5 mol% Fe2O3 decreases sharply with increasing duration of heat treatment up to 6 h and then remains almost constant. The sharp decrease in magnetic susceptibility of 2.5 mol% Fe2O3 is attributed to the increase in the number of ferrous ions. The sharp decrease for samples containing 5.0 and 7.5 mol% Fe2O3 is attributed to the increase in the number of Fe3+ in tetrahedral co-ordination. The rate of crystallization owing to the heat treatment was calculated and was found to increase with increasing iron oxide content. The geometry of crystallization was found to be in three-, two-and one-dimension(s) for samples containing 2.5, 5.0 and 7.5 mol% Fe2O3, respectively. 相似文献
77.
Effect of the percentage carbon equivalent on the nodule characteristics,density and modulus of elasticity of ductile cast iron 总被引:1,自引:0,他引:1
Nabil Fatahalla Hani Abd Al Hakim Aly Abo-El-Ezz Moenes Mohamed 《Journal of Materials Science》1996,31(18):4933-4937
Successful melting and Mg treatment were conducted using a vortex unit which produced spheroidal graphite (SG) Fe ingots having a percentage carbon equivalent (%CE) ranging from 3.782 to 5.240. Microstructure examination revealed graphite nodules embedded in a white matrix (unetched condition). The variation of %CE proved to have a pronounced effect on the nodule characteristics. The nodule count showed a maximum value at %CE of 4.613. For metal-mould ingots it reached a value of 1584 nodules mm–2, while for sand-mould ingots it reached a value of 970 nodules mm–2. Nodule size was found to be inversely proportional to the nodule count for both sand- and metal-mould ingots. The nodularity of all ingots was, in general, higher than 95%. The density of SG Fe was found to decrease gradually (at %CE=3.782) from 7242 to 6969 kg m–3. The modulus of elasticity (E) showed a boat-like curve having minimum values of 189 and 192 GPa for the sand and metal moulds, respectively. 相似文献
78.
M. M. Abd El-Raheem M. M. Wakkad N. M. Megahed A. M. Ahmed E. K. Shokr M. Dongol 《Journal of Materials Science》1996,31(21):5759-5764
Chalcogenide glasses with composition Ge20Se80–x
Tl
x
(x=10, 15, 20, 25, 35%) have been prepared by the usual melt-quenching technique. Thin films of the mentioned compositions have been prepared by the electron beam evaporation. In addition, another set taken from the composition ofX=30 at % with different thicknesses (d=14.7, 30.0, 56.5, 70.0, 101.0, 180.0 nm) have been taken into consideration. The X-ray diffraction (XRD) analysis revealed the amorphous nature of the prepared films. It was found that, in contrast to the optical gap (E
op), both the extent of the band tailing (B), and the band gap (E
e) increase with increasing thallium content. In other side,E
op showed thickness independency. The refractive index (n) showed obvious dependence on both composition and thickness also on the energy of the incident radiation. 相似文献
79.
Results from applying the model on a sample of contractors, the majority of whom were international and operating in Egypt, reinforces the credibility of the developed methodology, claim the authors. 相似文献
80.
S.H. Tantawi I.Z.Selim 《材料科学技术学报》1996,12(2):95-99
The use of a natural white juice, taken from magrabe banana stem, as concrete admixture to improve mechanical and physicrvchemical properties of concrete has been studied. The compressive strength, bulk density the free lime liberated during hydration and the combined water content were determined. The results indicate that the admixture acts as a retarder in most cases and as accelerator in some ones. Also, the admixture effect on the corrosion resistance of the reinforcing steel against surrounding aggressive media has been investigated using galvanostatic polarization technique. The addition of 0.2% admixture leads to the more inhibition of the steel 相似文献