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911.
    
This paper describes a structured analytical approach for selecting a manufacturing technology. A framework consisting of six integrated steps is proposed by considering the growing importance of supply chains in manufacturing organisations. The framework makes use of the analytical hierarchy process (AHP) approach combined with strategic assessment model (SAM) to evaluate and select the technologies appropriate for providing overall competitive advantage. The framework is intended to assist industrial managers in promoting manufacturing and supply chain collaboration and co-ordination by including intra-organisational perspective in their organisational technology selection decision making process.  相似文献   
912.
    
Adhesively bonded technology is now widely accepted as a valuable tool in mechanical design, allowing the production of connections with a very good strength‐to‐weight ratio. The bonding may be made between metal–metal, metal–composite or composite–composite. In the automotive industry, elastomeric adhesives such as polyurethanes are used in structural applications such as windshield bonding because they present important advantages in terms of damping, impact, fatigue and safety, which are critical factors. For efficient designs of adhesively bonded structures, the knowledge of the relationship between substrates and the adhesive layer is essential. The aim of this work, via an experimental study, is to carry out and quantify the various variables affecting the strength of single-lap joints (SLJs), especially the effect of the surface preparation and adhesive thickness. Aluminium SLJs were fabricated and tested to assess the adhesive performance in a joint. The effect of the bondline thickness on the lap-shear strength of the adhesives was studied. A decrease in surface roughness was found to increase the shear strength of the SLJs. Experimental results showed that rougher surfaces have less wettability which is coherent with shear strength tests. However, increasing the adhesive thickness decreased the shear strength of SLJs. Indeed, a numerical model was developed to search the impact of increasing adhesive thickness on the interface of the adherend.  相似文献   
913.
914.
    
Hydrogel scaffolds for tissue engineering are important biomaterials. The target in this study was to prepare polyvinyl alcohol/hyaluronic acid hydrogels for the encapsulation of chondrocyte cells by a simple cross‐linking reaction. Control of the swelling properties and morphology of the hydrogels for cultivation of chondrocytes was studied. The hydrogels were prepared from polyvinyl alcohol and hyaluronic acid derivatives bearing primary amine and aldehyde functionalities, respectively. The formation of the hydrogel upon mixing the aqueous solutions of the polymer derivatives took place at room temperature in a few seconds. The swelling properties of the hydrogels were found to depend on the polymer concentration and degree of substitution of the modified polymers. Scanning electron microscopy studies showed that the hydrogels had a suitable porous morphology for cell encapsulation. Furthermore, in vitro cell viability tests with the hydrogels showed no cytotoxicity for chondrocytes and that the cells grew well in the hydrogel scaffolds. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42272.  相似文献   
915.
    
BACKROUND: Hydrocarbon contamination of groundwater resources has become a major environmental and human health concern in many parts of the world. Microbial degradation of hydrocarbons, through either naturally occurring processes or engineered systems, has been successfully used to reduce concentrations of these pollutants. In order to develop an aerobic bioreactor tailored for this purpose, the present study aims to investigate petroleum contaminated wastewater remediation and toxicity reduction by acclimated microbial consortium enriched in a continuous stirred tank bioreactor (CSTR). Characterization and quantification of refinery wastewater components were performed by gas chromatography mass spectrometry (GC/MS) and Fourier transform infrared (FTIR) spectroscopy. RESULTS: The petroleum hydrocarbons were significantly degraded (97%) by the microbial consortium. After continuous aerobic treatment in the CSTR, the CODeffluent and BOD5effluent average removals were high reaching 97% and 78%, respectively. Also, strong degradation of C10? C35 n‐alkanes was observed. The concomitant use of GC/MS and FTIR proved to be a useful complementary tool to assess the impact of treatment strategies on hydrocarbon‐contaminated wastewater. In addition, the toxicity of the contaminated wastewater decreased drastically after bioremediation. CONCLUSION: This work shows the ability of this consortium to degrade hydrocarbons and reduce toxicity, which makes them useful candidates for environmental restoration applications at other hydrocarbon‐contaminated environments. Copyright © 2011 Society of Chemical Industry  相似文献   
916.
    
BACKGROUND: Dyeing effluents are the main source of water pollution from textile industries. Consequently, the treatment of such effluents is of environmental concern. RESULTS: Decolorization of a textile industry effluent was investigated using, for the first time, the trimeric Scytalidium thermophilum laccase without mediator addition. The maximum effluent decolorization (50%) was achieved after 8 h using a diluted effluent (5 fold) and 4 units of crude enzyme, operating at 50 °C and pH 4. Characterization of raw effluent presents two peaks as demonstrated by the UV‐visible spectrum, showing an intensive peak around 670 nm and a smaller one at 290 nm. At the end of the enzymatic treatment, these two peaks disappeared and a new peak emerged at 280 nm. Because laccase catalyzed effluent decolorization percentage did not exceed 50%, an alkaline adapted consortium treatment assay of this effluent was carried out. An alkaline adapted consortium was used at bench scale in order to decolorize the raw effluent. After 24 h of exposure, color and COD (chemical oxygen demand) removal rates reached 73% and 71%, respectively, at pH 11. CONCLUSION: The adapted consortium treatment of the industrial effluent is economically very interesting since the treatment is costless and can be applied at pilot or industrial scales. © 2012 Society of Chemical Industry  相似文献   
917.
    
In the present work the reinforcing potential of nanofibrillated cellulose (NFC) from five different non‐woody plants, namely; abaca, sisal, hemp, jute and flax was investigated. Nanocomposite materials were prepared by casting a mixture of NFC suspension and a polymer waterborne latex dispersion, and their mechanical properties in both linear and nonlinear ranges as well as the optical properties of the ensuing films were analyzed. Irrespective of their origin, the incorporation of the NFC within the polymer matrix brings about a huge reinforcing effect above the glass transition. The percolation approach has been shown to give a reasonably accurate prediction of the stiffness over the whole range of volume fraction investigated. The evolution of the magnitude of tan δ vs. the NFC content was also analyzed and discussed in term of the effective interfacial thickness. The optical transparency of the nanocomposite film at different NFC content was also studied and compared according to the NFC origin. POLYM. COMPOS., 34:1999–2007, 2013. © 2013 Society of Plastics Engineers  相似文献   
918.
    
Sami Arsoy 《Drying Technology》2013,31(12):1477-1483
Measurement of the moisture content of inorganic soils is frequently needed for many engineering activities. The standard test method by ASTM D2216 is very accurate, but the associated drying time up to 24 h is not always desirable. This study investigates the usability of infrared (IR) drying of inorganic soils in reducing the drying time under constant temperature. It was found that accuracy of the proposed IR oven method is excellent and the associated drying time is 80% less than that of a conventional convective oven. Drying time for zero plasticity soils such as sands was found to be about 1 min per gram of initial sample mass. Soil plasticity was found to increase the drying time up to 100% compared to that of zero plasticity soils.  相似文献   
919.
920.
Several white rot fungi were evaluated for their ability to decolorize olive mill waste-waters (OMW). Among these, Phanerochaete chrysosporium showed the highest potential for the biological depollution of OMW. Approximately 65% of the color and 73% of the chemical oxygen demand (COD) were removed by P. chrysosporium strain HD. Phlebia radiata, Dichomitus squalens, Polyporus frondosus and Coriolus versicolor could also decolorize the OMW but to a lesser extent. The different abilities of these white rot fungi to decolorize OMW correlated with their rates of depolymerization of high molecular weight aromatics and the degradation of the low molecular weight aromatic compounds. Fourteen strains of P. chrysosporium were compared on the basis of their lignin peroxidase (LiP) production, OMW decolorization and residual material dry weight. High lignin peroxidase producer strains, such as strains HD and BKM-F-1767, showed the highest rates of OMW decolorization, P. chrysosporium strains 79–36 and FP 104297 (low LiP producer strains) did not exhibit any decolorization activity.  相似文献   
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