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排序方式: 共有1726条查询结果,搜索用时 15 毫秒
141.
V. C. Santos A. A. R. Fernandes 《Journal of Materials Science: Materials in Electronics》1999,10(1):67-70
Ferromagnetic resonance measurements on different Fe/Cr multilayer samples with the same thickness of the spacing Cr layers suggest that these multilayers have a different magnetic behavior depending on the thickness of the active Fe layers. In this work we show that the change of magnetic behavior from bulk mode to surface mode is observed only when the thickness of the Fe layers is less than 4 nm. This is attributed to the Fe layer thickness and to the relative thickness of the magnetic and non-magnetic layers. ©1999Kluwer Academic Publishers 相似文献
142.
143.
Villas J.E.T. Mukhedkar D. Fernandes V.R. Magalhaes A.C. 《Power Delivery, IEEE Transactions on》1990,5(1):124-129
E.T.D. Barra Funda I urban station, located in Sao Paulo, Brazil, is surrounded by several buildings, so it is not possible to make reliable earth resistivity and ground electrode resistance measurements. The grounding of this station was designed by using external circuits connected to the ground mat (sheaths and bare copper bondings). The use of these circuits allows a transfer of the fault potentials from E.T.D. Barra Funda I to E.T.R. Barra Funda II due to a strong cable shielding. A discussion is presented of the basic procedures adopted for controlling the potential rise at the E.T.D. Barra Funda I station in order to ensure the safety of people and equipment during the occurrence of a fault to the ground. This study deals with such design aspects as: high short-circuit level, high soil resistivity and backup protection time, and reduced area for diffusion of short-circuit current 相似文献
144.
145.
The objective of the study presented here was to investigate the performance of an enhanced two-step anaerobic process for the treatment of WWTP sludge. This process was developed to answer the urgent need currently faced by WWTP operators to reduce the production of biosolids, for which disposal pathways are facing increasing difficulties. A pilot plant was operated on a full-scale WWTP (2,500 p.e.) over a period of 4 months. It consisted of a thermal pre-treatment of excess sludge at 175 degrees C and 40 min, followed by dewatering and methanisation of the centrate in a fixed-film reactor. The thermal lysis had a two-fold enhancing effect on sludge reduction efficiency: firstly, it allowed a decrease of the HRT in the methaniser to 2.9 days and secondly, it yielded biosolids with a high dewaterability. This contributed to further reductions in the final volume of sludge to be disposed of. The two-step process achieved a sludge reduction efficiency of 65% as TSS, thus giving an interesting treatment option for WWTP facing sludge disposal problems. 相似文献
146.
MA de Oliveira VF Bruno LS Ballini JR BritoJardim AL Fernandes 《Canadian Metallurgical Quarterly》1997,34(5):395-403
We have developed a 6-month educational plan associated with outpatient follow-up and special clinical care for asthmatic patients in a deprived population, with serious socioeconomic problems and a very low level of education. The objective was to determine the effects of the program on clinical asthma outcomes, lung function, and quality of life. Forty patients were enrolled in the program with a regular schedule of outpatient visits, and 31 finished the 6-month intervention, which included information about asthma, instruction in appropriate use of medication, training in metered-dose inhaler technique, how to identify and control asthma triggers, how to use symptom diary cards, and how to recognize early signs of deterioration. Patients included 8 males and 23 females, 47.8 +/- 16.5 years old, with 77.4% elementary school education and 22.6% illiterate, and an average monthly income of around $450. After the 6-month program there was a significant change in asthma control with a reduction in asthma emergency visits and hospitalization, reduction of score symptoms, and improvement in quality of life. Based on the results, educational programs are recommended and should be adapted to the socioeconomic and cultural characteristics of the target population. 相似文献
147.
CM Fernandes 《Canadian Metallurgical Quarterly》1995,332(21):1446; author reply 1446-1446; author reply 1447
148.
SJ Schwarz JR Claus H Wang NG Marriott PP Graham CF Fernandes 《Canadian Metallurgical Quarterly》1997,76(10):1450-1456
The pink color defect in cooked, uncured turkey is a sporadic problem that can result in economic loss and consumer dissatisfaction. Fourteen ligands were tested in ground turkey samples for their ability to reduce pink color development in control samples and in the presence of 150 ppm sodium nitrite or 1.0% nicotinamide (pink color producing agents). The 14 ligands evaluated were: 3-amino pyridine (AP), 4-benzoylpyridine (BP), diethylenetriamine pentaacetic acid (DA), ethylenedinitrilo-tetraacetic acid disodium salt (EA), 2,3 dihydroxybenzoic acid (DB), 3-ethyl pyridine (EP), trans 1,2-diaminocyclohexane-N,N,N',N' tetraacetic acid monohydrate (HA), calcium reduced nonfat dried milk (NM), 2,3 phthalic acid (PA), 3-picoline (PC), pyrrole (PY), pyridazine (PZ), pyridinedicarboxcylic acid (YA), and pyrazinedicarboxcylic acid (ZA). All ligands were incorporated into ground turkey at 0.20 mg/g (meat weight basis) except for NM (30 mg/g). Color was evaluated using a reflectance spectrophotometer to measure pigment changes (nicotinamide hemochrome, nitrosohemochrome) and with a chroma meter to determine CIE L* a* b* values. Reduction in pink color development was apparent with the addition of the ligand alone and in the presence of sodium nitrite and especially nicotinamide. The four most effective ligands tested were DA, EA, HA, and NM. In general, pink color reduction was highest in the ligand only and the ligand plus nicotinamide samples as was observed by CIE a* and nicotinamide hemochrome value reductions. 相似文献
149.
Lyrene Fernandes da Silva Virginia C. Carneiro de Paula 《Electronic Notes in Theoretical Computer Science》2002,65(4):117-128
The need to model systems and their different aspects leads to research and development of models which support all views of a system. The growing complexity of the software imposes the use of architectures, not only because we want to build accurate systems, but also because we need to understand them. Separating aspects of different views usually helps us to manage software complexity. The current work is an analysis of two important approaches on architectural views and on the use of UML to reason about views. Our goal is to analyze the different aspects addressed by them and how UML is inserted on each of these models. 相似文献
150.
Pedro M. P. Salomé Paulo A. Fernandes Joaquim P. Leitão Marta G. Sousa Jennifer P. Teixeira António F. da Cunha 《Journal of Materials Science》2014,49(21):7425-7436
In this work, we present the Raman peak positions of the quaternary pure selenide compound Cu \(_2\) ZnSnSe \(_4\) (CZTSe) and related secondary phases that were grown and studied under the same conditions. A vast discussion about the position of the X-ray diffraction (XRD) reflections of these compounds is presented. It is known that by using XRD only, CZTSe can be identified but nothing can be said about the presence of some secondary phases. Thin films of CZTSe, Cu \(_2\) SnSe \(_3\) , ZnSe, SnSe, SnSe \(_2\) , MoSe \(_2\) and a-Se were grown, which allowed their investigation by Raman spectroscopy (RS). Here we present all the Raman spectra of these phases and discuss the similarities with the spectra of CZTSe. The effective analysis depth for the common back-scattering geometry commonly used in RS measurements, as well as the laser penetration depth for photoluminescence (PL) were estimated for different wavelength values. The observed asymmetric PL band on a CZTSe film is compatible with the presence of CZTSe single-phase and is discussed in the scope of the fluctuating potentials' model. The estimated bandgap energy is close to the values obtained from absorption measurements. In general, the phase identification of CZTSe benefits from the contributions of RS and PL along with the XRD discussion. 相似文献