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51.
52.
In the present study, a new technique to synthesize composites of poly(methyl methacrylate) cerium molybdate (PMMA–CeMoO4) is reported. The study concerns the characterization of poly(methyl methacrylate; PMMA) and PMMA–CeMoO4 nanocomposites are also discussed. The physical properties of the material were described using TGA–DTA, FTIR, X‐ray, TEM, and SEM studies. The adsorption efficiency towards heavy metal ions was determined by distribution studies and material was found to be highly selective for lead, a heavy toxic metal ion, indicating the utility of the synthesized material for the removal of this ion from the waste stream. The material was used as electroactive component for the construction of an ion‐selective membrane electrode. The membrane electrode was mechanically stable, having wide dynamic range, with quick response time and could be operated for at least 5 months without any considerable divergence in the potential response characteristics. The electrode was successfully used as indicator electrode in complexation titrations. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
53.
The scientific literature is replete with examples that indicate that poor indoor conditions at workplaces reduce work performance and increase short-term sick leave. To address good indoor environment quality (IEQ), strategic and practical design decisions are needed in the early phase of the building process to ensure successful implementation. However, current procurement practices are hampered by fragmentation, long subcontract chains and vague performance requirements. A preliminary study is undertaken that focuses on developing a method of contracting that enables the attainment and verification of the desired IEQ. Using a review of international research and practices, existing commissioning methods and contract procedures are identified for their attention to IEQ. A contract procedure is proposed that fosters agreement on indoor environment between building owners and tenants, and which directs a building project to give users the guarantee of indoor condition. To make a pre-lease contract agreement that includes IEQ, the factors having an influence on the IEQ chain must be included in all building contracts such as those of design, purchase, and operation and maintenance. Thus, the requirements of IEQ require their incorporation into every phase of the building project. The main elements in these contracts, in addition to the requirements of IEQ, are those verifying quality, bonuses and sanctions. La littérature scientifique est riche en exemples qui montrent que la médiocrité des conditions intérieures sur le lieu de travail réduit les performances opérationnelles et augmente les absences de courte durée pour raisons de santé. Pour obtenir un environnement intérieur de bonne qualité (IEQ), il faut, dès le début du processus de construction, prendre des décisions d'ordre stratégique et pratique en vue d'une mise en ?uvre réussie. Or, la fragmentation, les longues chaînes de contrats de sous-traitance et le manque de précision des impératifs de performance sont autant d'obstacles aux pratiques d'approvisionnement actuelles. Une étude préliminaire est entreprise qui porte, pour l'essentiel, sur le développement d'un mode de réalisation permettant de satisfaire et de vérifier la qualité de l'environnement intérieur recherchée. S'appuyant sur une analyse des pratiques et de la recherche au niveau international, l'auteur recense les méthodes de mise en service et les procédures contractuelles existantes en fonction de l'intérêt porté à l'IEQ. Il est proposé une procédure contractuelle qui encourage les accords en matière d'environnement intérieur entre propriétaires de bâtiments et occupants et qui prescrit un projet de construction offrant aux utilisateurs la garantie d'un environnement intérieur satisfaisant. Pour conclure une convention contractuelle, préalablement au bail de location, qui prévoit l'IEQ, il faut inclure les facteurs ayant une influence sur la chaîne IEQ dans tous les contrats de bâtiments, comme la conception, l'approvisionnement, l'exploitation et la maintenance. Les exigences en matière d'IEQ nécessitent donc qu'elles soient intégrées à toutes les phases d'un projet de bâtiment. Les principaux éléments dans ces contrats, outre les exigences d'IEQ, sont ceux qui vérifient la qualité, les primes et les sanctions. 相似文献
54.
The purpose of this paper is to present and analyse the regulatory issues emerging from the newly launched programme of rural electricity access in India. We focus on two broad areas, namely regulatory issues related to the organisation/structuring of the activities and issues related to subsidy and tariffs. 相似文献
55.
Karoliina Koski Eveliina Koski Juha Virtanen Toni Bj?rninen Lauri Syd?nheimo Leena Ukkonen Atef Z. Elsherbeni 《The International Journal of Advanced Manufacturing Technology》2012,62(1-4):167-182
In this paper, the performance and the feasibility of inkjet-printed dipole RFID tag antennas are experimentally studied in the implementation of identifying objects with different electromagnetic properties. To estimate the performance quality, we compare our results to those obtained using traditional etched copper dipole tag antennas. We first examine the performance characteristics, i.e. the read range and the radiation patterns, of tags in free space. Then we attach the tags directly to target objects and compare the optimum performance on target objects to that of the tag in free space. The obtained results provide information about the behaviour of inkjet-printed tag antennas on different objects. This information can be used to optimize the inkjet-printed tag antenna performance for use on objects with different characteristics. 相似文献
56.
Tae-Gyu Nam R. Sangaiah Avram Gold Gregory D. Lacks Leena A. Nylander-French John E. French 《Polycyclic Aromatic Compounds》2013,33(3-4):239-248
The sulfhydryl group of cysteine residues is a site for the adduction of ultimate carcinogenic arene oxide metabolites to the proteins keratin 1 and keratin 10, dominant proteins of the squame. The putative cysteine adducts are: S -phenylcysteine, from benzene oxide and S -(1-naphthyl)- and S -(2-naphthyl)cysteine from naphthalene-1,2-oxide. In developing ELISAs for monitoring dermal exposures, we have embarked on synthesis of adducted head sequences GGRFSS(C*)GG (keratin 1) and GGGG(C*)GGGGG (keratin 10) by 9-fluorenyl-methoxycarbonyl chemistry to use in raising epitope-specific antibodies. Synthesis of the FMOC-protected cysteines was based on addition of arylthiols to 2-acetamidoacrylic acid, to give S -arylmercapturic acids. Removal of the N -acetyl group was accomplished quantitatively by extended refluxing in 1:1 t -butanol/concentrated HCl. FMOC derivatization of the S -arylcysteines was accomplished by a published procedure, modified because of the low solubility. The oligopeptides (C* = S -phenylcysteinyl residue) have been synthesized and characterized. 相似文献
57.
Leena Varila Susanne Fagerlund Timo Lehtonen Jukka Tuominen Leena Hupa 《Journal of the European Ceramic Society》2012,32(11):2757-2763
In vitro bioactivity of glasses is usually measured in buffered solutions whereby a formation of a hydroxyapatite layer on the surface is taken as an indication of the bioactivity. In this work we compare the layer formation on three glasses in simulated body fluid, Tris buffer solution, sodium phosphate buffered saline and osteoblast medium. Two of the glasses are known bioactive glasses, 45S5 (45 wt.% SiO2) and S53P4 (53 wt.% SiO2), while the third is an experimental composition with a higher silica content (68 wt.% SiO2). Plates of the glasses were immersed in the solutions at 37 °C for different times up to two weeks. The results showed clear differences between the layer developments on the three glasses in the different solutions. The results indicated that the relative order of the reactivity depended on the solution. Thus, results gained in different solutions for different glasses cannot be directly compared. 相似文献
58.
This article considers the detection of image features in different spatial scales. The main focus is on capturing the scale-dependent differences in a pair of noisy images, but the technique developed can also be applied to the analysis of single images. The approach proposed uses Bayesian statistical modeling and simulation-based inference, and it can be viewed as a further development of SiZer technology, originally designed for nonparametric curve fitting. Numerical examples include artificial test images and a preliminary analysis of a pair of Landsat images used in satellite-based forest inventory. This article has supplementary material online. 相似文献
59.
Preparation and properties of alkyd–acrylic hybrids have been studied. Hybrids with different alkyd–acrylic ratios and acrylic parts were prepared via free radical polymerization of acrylic monomers in a presence of an unsaturated alkyd resin using emulsion polymerization technique. The binders were characterized according to their solid content, conversion, viscosity, pH and particle size. Evidence on formation of true copolymer was obtained via NMR spectroscopy and molecular weight and glass transition temperature measurements, as well as via performance studies. The performance evaluation was focused on investigation of drying, penetration and water repellency ability, as well as on film formation and surface topography studies. The binders were compared to references of an alkyd emulsion, acrylic latex and a blend made of them. The results showed that alkyd–acrylic hybrids with synergistic and improved properties can be prepared. 相似文献
60.
Jesper Lundbom Marjukka Kolehmainen Leena Pulkkinen Pasi Soininen Mika Tiainen Ursula Schwab Matti Uusitupa Markku Tammi 《European Journal of Lipid Science and Technology》2010,112(12):1308-1314
The aim of this study was to evaluate use of infrared spectroscopy for measuring adipose tissue triacylglycerols (TAGs) with analysis by multivariate curve resolution (MCR). The mid‐infrared spectrum was measured with an attenuated total reflection accessory from a lipid droplet pressed from adipose tissue. The obtained spectra were characteristic of pure TAG spectra and water and protein contamination could be easily identified from specific spectral regions. MCR analysis of the olefinic (?C? H) stretch (3006 cm?1), resolved the different contributions of monounsaturated (MUFA) and polyunsaturated (PUFA) double bonds. Similar MCR analysis of the trans (HC?CH? ) region (966 cm?1), resolved the differing contributions of isolated trans isomers (transFA) and CLA. The PUFA double bond content of 16 subjects was negatively correlated with concentrations of serum total cholesterol R = ?0.498 (p = 0.050) and triacylglycerols R = ?0.609, (p = 0.016). The transFA content exhibited a negative, although non‐significant, correlation to high‐density lipoprotein (HDL)‐cholesterol (R = ?0.483, p = 0.068). The present study shows that MCR analysis of adipose tissue TAG infrared spectra can be used to estimate differences in the fatty acid (FA) profiles in population studies. Infrared spectroscopy in combination with MCR provides a robust method for assessing a FA profile of human adipose tissue. Practical applications: This study has highlighted the use of MCR to enhance the information obtained from infrared spectra. This new approach provides a robust method for assessing a FA profile of human adipose tissue lipids. 相似文献