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141.
Giovanni Arvedi Luciano Manini Andrea Bianchi Antonio Guindani Federico Mazzolari Ulrich Siegers 《钢铁》2004,39(Z1):472-478
1992年,在克日莫那的阿维迪钢厂新建了一条以生产薄板为基础的板材紧凑式生产线,这是欧洲第一、世界第二条薄板生产线.该生产线主要生产高质量钢和特殊钢.数据表明平均每浇次浇11炉钢,56%以上的产品规格都小于2mm厚,经连轧轧成1250mm宽1mm厚的薄板材.可以生产大部分钢种,例如低、中、高碳钢(0.75%),1.2mm的高强度低合金钢,硼钢,耐候钢,合金钢,包晶钢和双相钢等.明年,准备采取措施在一座115t电炉和单流最大宽度为1300mm的生产线上达到100万t的产量.引进铁素体轧制,发展热轧来生产更薄规格的钢以及多相铁素体-马氏体、铁素体-贝氏体钢.和其它薄板生产技术相比,AST(Arvedi Steel Technology阿维迪厂技术)有如下7项优势薄板液芯压下技术,能使板坯中心晶粒细化、温度分布均匀;在线低速轧制(低拉速),从而使中间坯凸度<1%;板坯厚度方向上的反向温度分布;感应加热炉精确、灵活的温度控制制度;稳定的终轧温度;根据最终薄带的厚度和温度来预设一个恒定的板坯精轧速度;经过克日莫那炉的无头轧制.优良的产品是经过先进的、控制精确的二次、三次冶金生产的.本文将着重陈述阿维迪钢厂的实践要点.并将叙述一些变换成本、高附加值产品及其经济结果.阿维迪有2条年产250万t的生产线,用来生产宽度接近于1600~1800mm的钢种.实践证明,AST的效益归功于它的极高的拉速以及直接无头轧制的思想.目前,AST将上一条高拉速(7.5m/min)的带有精轧的铸轧生产线.阿维迪的ECR的工艺(无头轧制)能够生产0.7mm厚的所有冷轧能生产的同种规格的产品,该工艺还能够生产IF钢(汽车板)、多相钢、薄带甚至有高延伸率和抗拉强度等特殊性能的钢,用来满足汽车工业的需要.克日莫那的阿维迪钢厂用高生产力、低成本生产各种质量的钢种,因此经济效益很好.阿维迪是这项技术的拥有者,准备以阿维迪的名义来购买掉这项技术,其中包括钢液准备、薄带制作以及薄带精整技术. 相似文献
142.
Susana Nieto Argelia Garrido Julio Sanhueza Luis A. Loyola Glauco Morales Federico Leighton Alfonso Valenzuela 《Journal of the American Oil Chemists' Society》1993,70(8):773-778
The antioxidant activities against fish oil oxidation of six commercially available flavonoids and of five flavonoids purified
from two Chilean native plants were compared to those ofdl-α-tocopherol and of two synthetic antioxidants, butylated hydroxytoluene and butylated hydroxyanisole. Among the commercial
flavonoids, catechin, morin and quercetin showed a higher activity when fish oil oxidation (either spontaneous or Fe2+-induced) was assessed from the formation of peroxides or thiobarbituric acid-reactive substances. Among the native flavonoids,
the 5,3′,4′-trihydroxy-7-methoxy flavanone (designated as Pt-2) showed the highest antioxidant activity. Mixtures of quercetin
or of Pt-2 withdl-α-tocopherol produced better inhibitory effects when compared to that of each substance assayed by itself. Also, when Pt-2
and quercetin were assayed in combination (0.3 g/kg oil and 0.7 g/kg oil, respectively), a synergistic antioxidant effect
was observed. Results indicate that several flavonoids could be used as natural antioxidants as a means to replace those synthetic
antioxidants, the use of which has been questioned. 相似文献
143.
Maurizio Bianchi Federico Ferioli Massimiliano Petracci Maria Fiorenza Caboni Claudio Cavani 《European Food Research and Technology》2009,229(2):339-348
The influence of dietary lipid source [animal fats (AF) and vegetable oils (VO)] on quality characteristics of raw chicken
meat (breast, thigh and meat batter) and cooked breaded patties prepared using a conventional technology (CT; forming, battering,
breading, frying and convection cooking) or innovative technology (IT; forming, pre-dusting, steam cooking, battering and
frying) was evaluated. Overall, dietary lipid source did not influence the chemical composition of raw meat while it modified its colour (L*, a*, b*). With respect to AF, VO produced higher breast and thigh meat cooking losses as well as a lower moisture and
higher protein content of cooked breaded patties. VO also determined an increase of polyunsaturated-to-saturated fatty acid
ratio of both raw and processed meat. Despite the different fatty acid profiles, the oxidative status of lipids was not affected
by dietary lipid source and was acceptable in both raw meat and cooked patties as indicated by peroxide and thiobarbituric
acid reactive substance values. As for the processing technology, IT determined a higher moisture and lower lipid content
of the cooked breaded patties. Moreover, lipolysis degree was slightly higher in the products coming from IT. Finally, patties
from AF group were lighter and more yellow than products belonging to VO group whereas IT led to lighter, less red and more
yellow patties in comparison to CT. 相似文献
144.
145.
S Pagni A McKelvey C Riordan JA Federico RB Ponn 《Canadian Metallurgical Quarterly》1998,14(1):40-4; discussion 44-5
OBJECTIVE: There is an increasing number of elderly patients presenting with potentially-resectable lung malignancy. The objective of this study is to evaluate the modern perioperative morbidity and mortality in patients undergoing oncologic lung resection and to analyse the trend over a 26-year period in our experience. METHODS: Between 1971 and 1996, 1506 patients underwent lung resection for malignancy. We reviewed the 30-day perioperative risk in a group of 385 (25.6%) patients aged 70 years and older operated on for intended cure of lung malignancy. Operations included 293 (77%) lobectomies, 24 pneumonectomies (6%), 16 bilobectomies (4%) and 52 wedge or segmental resections (13%). The pathology was bronchogenic carcinoma in 89% and metastasis or other tumours in 11% of patients. We compared the 30-day perioperative risk between the elderly group (age 70 or greater) and a cohort of 180 patients (control) 69 years and younger. RESULTS: The mortality for all resections in elderly group was 4.2% (16/385) and was 1.6% for the control group. Mortality in the octogenarian group was 2.8%. Female gender correlated with a decreased risk of death, with only two of 16 deaths in females (P < 0.005). Overall morbidity was higher in the study than in control patients (34% vs. 25%, n.s.), although major morbidity was similar in both groups (13.2% vs. 13%). Abnormal pulmonary-function testing and positive cardiac history did not correlate with increase overall or specific risk. Pneumonectomy carried a higher risk for death, with three of 24 deceased (12.5%; P < 0.05). Changes in outcome were analysed over two time periods: the mortality in the early period (1971-1982), 11.1% (8/72), was significantly elevated above the control group, while mortality in the modern period (1983-1994) was not, with a rate of 2.6% (8/313). CONCLUSIONS: In our series, mortality associated with operative treatment for lung malignancy in the elderly declined, so age alone no longer appears to be a risk factor. Age remains a risk factor for overall, but not major, morbidity. Pneumonectomy should undertaken cautiously in this age group. Based on this data, functional elderly patients should not be denied curative lung resection based on age alone. 相似文献
146.
F Loi G Battista GM Malentacchi C Paradiso A Pompella M Rubegni A Federico 《Canadian Metallurgical Quarterly》1981,2(3):283-290
Three members of a family were found be suffering from lead poisoning of nonindustrial origin, the causative agent being the home-produced wine left to ferment in a glazed earthenware vat. The clinical and neurophysiological features are discussed in the light of similar cases in the literature. Correct diagnosis and early treatment of nonindustrial lead polyneuropathy are often extremely difficult because of the elusive nature of the exposure. 相似文献
147.
Summary
Blends of recycled poly(ethylene terephthalate) (R-PET) and high-density polyethylene (R-PE), obtained from post-consumer
packaging materials, were prepared both by melt mixing and extrusion processes and compatibilized by addition of various copolymers
containing functional reactive groups, such as maleic anhydride, acrylic acid and glycidyl methacrylate. The effect of the
type and concentration of compatibilizer, as well as the mixing conditions, on the phase morphology, thermal behaviour, rheological
and mechanical properties of the blends was investigated. The results indicated that addition (5÷10 pph) of ethylene-co-glycidyl methacrylate copolymer (E-GMA) allows for a marked improvement of processability and physical/mechanical performances
of R-PET/R-PE blends.
Received: 1 March 2001/Revised version: 15 November 2001/ Accepted: 28 January 2002 相似文献
148.
Holder Mark D.; Bermudez-Rattoni Federico; Garcia John 《Canadian Metallurgical Quarterly》1988,102(3):363
In five experiments we attempted to establish aversions to a noise presented each time thirsty rats licked a water source. Using an apparatus and a procedure similar to those of previous studies which reported noise-illness associations, weak taste-potentiated noise-illness associations were found (Experiment 1). However, when the apparatus and procedure were varied, noise-illness associations were not observed (Experiments 3, 4, and 5). The noise used in all of these failures was readily associated with shock (Experiment 2), which indicates that this noise was salient to the rats and could be associated with an aversive event. These failures to find noise-illness associations occurred despite the fact that the conditions were chosen to maximize the likelihood of observing these associations. Taste-illness associations always developed normally. The results are consistent with the idea that conditioned aversions to all exteroceptive stimuli are not equally well potentiated by taste. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
149.
150.
We evaluate the use of smoothing splines with a weighted roughness measure for local denoising of the correlation fringes produced in digital speckle pattern interferometry. In particular, we also evaluate the performance of the multiplicative correlation operation between two speckle patterns that is proposed as an alternative procedure to generate the correlation fringes. It is shown that the application of a normalization algorithm to the smoothed correlation fringes reduces the excessive bias generated in the previous filtering stage. The evaluation is carried out by use of computer-simulated fringes that are generated for different average speckle sizes and intensities of the reference beam, including decorrelation effects. A comparison with filtering methods based on the continuous wavelet transform is also presented. Finally, the performance of the smoothing method in processing experimental data is illustrated. 相似文献