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131.
X-ray diffraction (XRD) and the X-ray photoelectron spectroscopy (XPS) were measured for the sintered BSCF ceramics (Ba0.5Sr0.5Co
x
Fe1−x
O3−δ, x = 0.2 and 0.8: BSCF5528 and BSCF5582, respectively), which were annealed at different temperatures (700 and 950 °C) and gases
(O2 and Ar). The unit cell of the annealed BSCF5528 at 950 °C under Ar expanded by 0.8%, while contracting by 0.45% under O2. The cubic and rhombohedral phases coexist in the BSCF5582 annealed at 700 °C under O2. The XPS peak areas of lattice oxygen (O2−) in O1s
, ~528 eV, and the shoulder peak of Co2p
/Ba3d
in BSCF5582 (~778 eV) increased significantly after being annealed in O2. The areas of the peaks for BaCO3 (87.9/90.2 eV) in Ba4d
preferentially were shown to decrease in Ar and increase in O2. 相似文献
132.
Auricular elastic cartilage is a potential source for lining of luminal surfaces of implantable vascular devices, such as stents and left ventricular assist devices with the purpose to improve their biocompatibility. Auricular chondrocytes are easily accessible, harvested, and isolated, and they have been shown to provide a strong adherent cell lining for left ventricular assist devices. Additionally, Dr. Rosenstrauch have shown that it is possible to genetically engineer auricular chondrocytes to produce antithrombogenic factors. Thus, implantable vascular devices, such as coronary stents covered with genetically engineered auricular chondrocytes might lower restenosis rates and provide a long-lasting biocompatible prosthesis. In this paper, to optimize the process of lining of artificial surfaces with auricular cartilage, we devise a mathematical model that describes the rate of cell division and growth of extracellular matrix as a function of the initial cell count, proximity to other cells, and the type of artificial surface. Our mathematical model was experimentally tested using two different cell cultures (auricular chondrocytes and dermal fibroblasts) seeded on different artificial surfaces (tc-treated polystyrene and aluminum foil). Excellent agreement between the model and experiment was obtained. This mathematical model can be used to, for example, determine the optimum number of initially seaded cells that would provide fastest coverage of a given artificial surface. 相似文献
133.
Peter Baron David Lesser Ian Robertson Doreen Parry Basil Lowman Neil Scott John Prescott 《Journal of the science of food and agriculture》1978,29(10):885-894
Previous studies of the acceptability of bull beef have relied on laboratory panel or mechanical tests. This study extends the assessment to a consumer panel who cooked and ate the conventionally prepared steaks in their own homes. The test showed consumers to distinguish bull steaks as leaner than steer steaks but not to discriminate on overall appearance. When it came to eating, however, bull steaks were judged to take longer to brown and be less satisfactory in terms of flavour, juiciness, tenderness and overall eating quality. On tenderness 11% of the sample marked the bull steaks as ?well below average’?. These results are sufficiently clear to suggest the need for a test of their commercial impact. 相似文献
134.
A sustainable and environmentally responsible building concept aims at a high workplace comfort, a significantly reduced heating and cooling demand, a high-efficient plant system, and the use of renewable energy sources to condition the built environment. This paper presents a comprehensive analysis of the heating and cooling concepts of 11 low-energy buildings in terms of energy use, efficiency and occupant thermal comfort. All buildings investigated employ environmental energy sources and sinks – such as the ground, ground water, rainwater and the ambient air – in combination with thermo-active building systems. A limited primary energy use of about 100 kWhprim/(m2neta) as a target for the complete building service technology (HVAC and lighting) was postulated for all buildings presented. With respect to this premise, a comprehensive long-term monitoring in high time resolution was carried out for two to five years, with an accompanying commissioning of the building performance. Measurements include the useful heating and cooling energy use, auxiliary energy use for the hydraulic system, as well as end and primary energy use, occupant thermal comfort and local meteorological conditions. A new methodology is proposed for a holistic approach to the evaluation of heating and cooling concepts, which not only considers the occupants thermal comfort, but also the useful energy consumption and the efficiency of the generation, distribution and delivery of heating and cooling energy. 相似文献
135.
Abstract: Tropical cyclones (TC) are often associated with severe weather conditions which cause great losses to lives and property. The precise classification of cyclone tracks is significantly important in the field of weather forecasting. In this paper we propose a novel hybrid model that integrates ontology and Support Vector Machine (SVM) to classify the tropical cyclone tracks into four types of classes namely straight, quasi-straight, curving and sinuous based on the track shape. Tropical Cyclone TRacks Ontology (TCTRO) described in this paper is a knowledge base which comprises of classes, objects and data properties that represent the interaction among the TC characteristics. A set of SWRL (Semantic Web Rule Language) rules are directly inserted to the TCTRO ontology for reasoning and inferring new knowledge from ontology. Furthermore, we propose a learning algorithm which utilizes the inferred knowledge for optimizing the feature subset. According to experiments on the IBTrACS dataset, the proposed ontology based SVM classifier achieves an accuracy of 98.3% with reduced classification error rates. 相似文献