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61.
End of life (EOL) phase of a product is receiving more attention due to increase in environmental concerns, and many studies have been conducted for value creation in EOL, focusing on concepts as remanufacturing, reuse and recycling in sustainable production manner. This study especially focuses on one of global problem, e-waste. To minimise the amount of wastes and maximise recovered materials from EOL, disassembly is one of the most important concept, associated with reuse, and balancing disassembly line in an optimal way is essential for organisations. In disassembly line balancing (DLB), not only precedence of tasks, but also risk criteria related to environment and human safety should be considered for sustainability. The aim of this study is to propose a model based on triple bottom line (TBL) dimensions, i.e. human safety, environmental safety and business criteria. To achieve sustainability in DLB, and for risk assessment in sustainable DLB, it had been decided to use a multi-criteria method, i.e. TODIM, acronym in Portuguese of ‘Tomada de Decisão Iterativa Multicritério’. The proposed model included 22 disassembly criteria categorised under TBL dimensions, which are derived from the literature. Implementation of the study was conducted for computer disassembly processes, and as a result of the study approximately 12% an improvement in cycle time was succeeded. In the long run, the integration of sustainability in disassembly operations may contribute to the competitive advantage of the company in terms of differentiation and corporate image by achieving business, environment and human targets simultaneously.  相似文献   
62.
The present study focused on dyeing, fastness, cytotoxic properties, and phenolic constituents of various types of fabrics including viscose, cotton, wool, and polyester-viscose blended fabrics with different parts of Anthemis tinctoria var. tinctoria. Comparative study was carried out between ethanol and aqueous extracts of stem, flower, and root of the plant in terms of phenolic constituents, cytotoxic activity, and dyeing properties. It was found that the quantity of phenolic constituents of ethanol and aqueous extracts was quite different. All parts of the plant extract show 0% cytotoxicity except ethanol extract of the root. All the extracts exhibit better cytotoxic activity than the standard cancer drug 5-Florouracil. Ethanol and water extracts of A. tinctoria var. tinctoria plant were used to dye fabrics, but only the water extract displayed dyeing properties. Best color strength value (K/S = 9.19) was obtained with aqueous extract of the stem in the presence of alum mordant for cotton fabrics.  相似文献   
63.
Neural Computing and Applications - In recent years, the computer vision applications in the robotics have been improved to approach human-like visual perception and scene/context understanding....  相似文献   
64.
The polyethyleneimine (PEI) microgels prepared via microemulsion polymerization are protonated by hydrochloric acid treatment (p‐PEI) and quaternized (q‐PEI) via modification reaction with methyl iodide and with bromo alkanes of different alkyl chain lengths such as 1‐bromoethane, 1‐bromobutane, 1‐bromohexane, and 1‐bromooctane. The bare p‐PEI and q‐PEI microgels are used as catalysts directly without any metal nanoparticles for the methanolysis reaction of sodium borohydride (NaBH4). Various parameters such as the protonation/quaternization reaction on PEI microgels, the amount of catalyst, the amount of NaBH4, and temperature are investigated for their effects on the hydrogen (H2) production rate. The reaction of self‐methanolysis of NaBH4 finishes in about 32.5 min, whereas the bare PEI microgel as catalyst finishes the methanolysis of NaBH4 in 22 min. Surprisingly, it is found that when the protonated PEI microgels are used as catalyst, the same methanolysis of NaBH4 is finished in 1.5 min. The highest H2 generation rate value is observed for protonated PEI microgels (10 mg) with 8013 mL of H2/(g of catalyst.min) for the methanolysis of NaBH4. Moreover, activation parameters are also calculated with activation energy value of 23.7 kJ/mol, enthalpy 20.9 kJ/mol, and entropy ?158 J/K.mol. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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66.
Thermal barrier coatings generally consist of a metallic substrate which is the primary structural component, a metallic bond coat which serves as oxygen diffusion barrier, a very thin layer of thermally grown oxide and a ceramic top coat that provides the main thermal shielding. Homogeneous ceramic coatings as top coats appear to have certain undesirable features such as high residual and thermal stresses, generally low toughness and relatively poor bonding strength. The new concept of compositional grading of the top coat may help to overcome some of these shortcomings by eliminating the material property discontinuities. A common mode of failure in thermal barrier coatings seems to be the debonding of the top coat. In this study the related interface crack problem for a graded ceramic/metal top coat is considered. It is assumed that the thermophysical properties of the top coat continuously vary between that of the bond coat at the top coat-bond coat interface and that of the ceramic at and near the free surface. The main objective of the study is to examine the influence of the material nonhomogeneity parameters and relative dimensions on the stress intensity factors and the crack opening displacements.  相似文献   
67.
The spin-1 model is studied on the Bethe lattice by including the bilinear J and biquadratic K exchange interactions into the Hamiltonian. The effects of J is randomized by using a bimodal random distribution with an adjustable parameter α which allows to study the cases of ±J-model and bond-dilution. The thermal variations of the order-parameters are studied to obtain the possible phase diagrams of the model. It is found that second-order phase transitions lines separate the ordered-phases, ferromagnetic, or antiferromagnetic, from the disordered one, i.e., the paramagnetic phase. The staggered quadrupolar phase lines are also found and only seen for higher negative K values for coordination number q=4 and 6, only. The reentrant behavior is also found for some of the phase transitions lines.  相似文献   
68.
ZrB2–SiC composites were prepared by spark plasma sintering (SPS) at temperatures of 1800–2100 °C for 180–300 s under a pressure of 20 MPa and at higher temperatures of above 2100 °C without a holding time under 10 MPa. Densification, microstructure and mechanical properties of ZrB2–SiC composites were investigated. Fully dense ZrB2–SiC composites containing 20–60 mass% SiC with a relative density of more than 99% were obtained at 2000 and 2100 °C for 180 s. Below 2120 °C, microstructures consisted of equiaxed ZrB2 grains with a size of 2–5 μm and α-SiC grains with a size of 2–4 μm. Morphological change from equiaxed to elongated α-SiC grains was observed at higher temperatures. Vickers hardness of ZrB2–SiC composites increased with increasing sintering temperature and SiC content up to 60 mass%, and ZrB2–SiC composite containing 60 mass% SiC sintered at 2100 °C for 180 s had the highest value of 26.8 GPa. The highest fracture toughness was observed for ZrB2–SiC composites containing 50 mass% SiC independent of sintering temperatures.  相似文献   
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70.
1. This study was to determine the effects of heat load early in life on thermoregulatory responses and whole blood viscosity of broilers during a subsequent exposure to high environmental temperature later in life. 2. The birds, which had been subjected to exposure to 38 degrees C for 24 h at 5-d-old, served as prior exposure group (group A). Both group A and control group B were exposed to 33 degrees C for 3 h when near marketable weight. 3. On exposure to 33 degrees C, although there were no significant differences in the increases in heat production (HP) between the two groups, abdominal temperature (Ta), temperature of external ear tract (Tee), shank skin temperature (Tss), standing-lying frequency and lying time were lower in group A than in group B. Heart rate (HR) and comb surface temperature (Tcs) did not differ but increased in both groups during exposure to 33 degrees C. Respiration rate (RR) was greater in group A. 4. Blood viscosity decreased markedly in both groups after exposure to 33 degrees C; the decrease was greater in group A. 5. These results suggest that early exposure may promote broilers' ability to cope with the subsequent heat load by altering thermoregulatory physiological responses and behavioural patterns, resulting in an alleviation of heat stress.  相似文献   
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