Synthesis and characterization of phosphorus-containing methacrylate-based difunctional crosslinkers and their use in UV-curable resin systems

Two new phosphorus-containing methacrylate-based difunctional crosslinking agents [bis(4-(2-methacryloyloxy)ethyl carboxyl)phenyl phosphine oxide (BEPPPO) and bis(4-(2-methacryloyloxy)ethylcarbonylaminophenyl)phenyl phosphine oxide (BUPPPO)], which can be good candidates for UV-curable coating applications, were synthesized by reacting either a phosphorus-containing diisocyanate [bis(4-isocyanatophenyl)phenyl phosphine oxide] or a phosphorus-containing diacid chloride [bis(4-chloroformylphenyl)phenyl phosphine oxide] with hydroxyethyl methacrylate. The structures of the monomers thus obtained were characterized by FTIR, mass, and ¹H-NMR spectroscopies. The contents of the new crosslinking agents in the UV-cured polymeric films were varied between 10 and 30% by weight. Mechanical, physical, and thermal characterizations of the UV-cured films were investigated. An increase in crosslinking agent content caused an increse in mechanical properties. Films containing BUPPPO had higher tensile strength values compared to the films containing BEPPPO. Thermogravimetric analysis of phosphorus-containing crosslinking agents revealed that incorporating phosphorus into the structure resulted in a high char yield up to 24.5% at 600°C. Water absorption values of UV-cured films were also affected by the amount and type of crosslinking agent. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2575–2585, 1999     

The Use of papaver somniferum L. Plant Extract as Corrosion Inhibitor

Protection of Metals and Physical Chemistry of Surfaces - The corrosion inhibition and adsorption characteristics of the extract obtained from the plant Papaver somniferum L. (PSL) by...     

Bioactive Sheath/Core nanofibers containing olive leaf extract

This study aimed at producing silk fibroin (SF)/hyaluronic acid (HA) and olive leaf extract (OLE) nanofibers with sheath/core morphology by coaxial electrospinning method, determining their antimicrobial properties, and examining release profiles of OLE from these coaxial nanofibers. Optimum electrospinning process and solution parameters were determined to obtain uniform and bead‐free coaxial nanofibers. Scanning electron microscopy and transmission electron microscopy (TEM) were used to characterize the morphology of the nanofibers. The antimicrobial activities of nanofibers were tested according to AATCC test method 100. Total phenolic content and total antioxidant activity were tested using in vitro batch release system. The quality and quantity of released components of OLE were determined by high‐performance liquid chromatography. The changes in nanofibers were examined by Fourier‐transform infrared spectroscopy. Uniform and bead‐free nanofibers were produced successfully. TEM images confirmed the coaxial structure. OLE‐loaded nanofibers demonstrated almost perfect antibacterial activities against both of gram‐negative and gram‐positive bacteria. Antifungal activity against C. albicans was rather poor. After a release period of 1 month, it was observed that ～70–95% of the OLE was released from nanofibers and it was still bioactive. Overall results indicate that the resultant shell/core nanofibers have a great potential to be used as biomaterials. Microsc. Res. Tech. 79:38–49, 2016. © 2015 Wiley Periodicals, Inc.     

Competitive adsorption of uranyl ions in the presence of Pb(II) and Cd(II) ions by poly(glycidyl methacrylate) microbeads carrying amidoxime groups and polarographic determination

The adsorption capacity of UO in the presence of Pb(II) and Cd(II) ions was investigated with amidoximated poly(glycidyl methacrylate) (PGMA) microbeads with an average size of 135 μm packed in a glass column (0.5‐cm i.d. and 20‐cm length, flow rate = 3 mL/min) under competitive conditions. A differential pulse polarography technique was used for the determination of trace quantities of uptaken elements by the measurement of the reduction peak currents at ?200/?950, ?400, and ?600 mV (vs a saturated calomel electrode) for UO, Pb(II), and Cd(II) ions, respectively. When only UO was found in the eluate, its adsorption was 85.3% from a 50 μM initial solution. However, when there was UO with binary systems of Pb(II) or Cd(II), it was 78.2 and 76.3%, respectively. On the other hand, in a ternary mixture of UO with Pb(II) and Cd(II), the adsorption was found to be 75.2% with the same initial concentration. According to the results, the competitive adsorption studies showed that these amidoximated PGMA microbeads had good adsorption selectivity for UO with the coexistence of Pb(II) and Cd(II) ions. The ionic strength of the solution also influenced the UO adsorption capacity of the amidoximated PGMA microbeads. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 4168–4172, 2007     

Assessment of material use in relation to climate in historical buildings

Climate is among the most significant factors on the environmental performance, life span and/or durability of construction materials in buildings. Although some historical buildings have been abandoned and neglected for a very long period, their existence through centuries can be explained because of their durability to climatic conditions of the area where they are situated. In this study, construction techniques and characteristics of building materials used in some madrasas (historical education buildings) in Western Anatolia (Turkey) were examined in order to evaluate the conditions of the buildings by taking into account climatic conditions of the region. The studied Western Anatolian madrasas, which are in the moderate climatic conditions, were constructed out of rubble stone, brick and mortar in random bond with local workmanship by local builders who continued the older traditions and have survived for more than 300 years without maintenance and repair. On the other hand, most of the madrasa buildings in Central and Eastern Anatolia, which are in the steppe climatic conditions, were differently constructed with cut stone on their exterior surfaces to prevent the main structures of the walls composed of rubble stone and mortar from harsh climatic conditions of these regions. This study indicated that construction techniques and building materials appropriate to the climate might have been intentionally chosen for the survival of historical buildings over the centuries.     

The challenge of change for innovation in construction: A North Cyprus perspective

A vision of change for innovation within the perspective of revaluing the construction industry is essential to develop a culture of self-sustaining improvement, mutual recognition, respect and support in the long term in North Cyprus. The research attempts to put forward a case for a restructuring of the construction sector in order to deliver a step in change in quality of output and to realise maximum value to all clients, stakeholders and end users. The main objective of this study is to (1) determine current innovation practices and identify key issues that contribute to successful implementation (2) assess the existence and severity of barriers to change for innovation (3) propose solutions for overcoming barriers to change for innovation in construction industry and develop a framework to revaluate the construction industry. The research includes an extensive literature study, interviews with managers on the challenge of change for innovation in construction, analysis of this information to develop findings, and extending these to present the key strategic issues that could be targeted for revaluing the construction industry. The paper commences on understanding the firms’ own processes and detecting their weaknesses and strengths, determining the strategies and actions that should be made in the short term to adopt innovation practices and helping the North Cyprus construction industry to learn as a whole. The paper concludes how the drivers of change for innovation can offer benefits to construction firms in North Cyprus if appropriate strategies are adopted.     

Durability of concrete incorporating non-ground blast furnace slag and bottom ash as fine aggregate

The paper presents investigation of how the usage of bottom ash (BA), granulated blast furnace slag (GBFS), and combination of both of these materials as fine aggregate in concrete affects the concrete durability. To assess durability characteristics of concrete, durability tests were conducted and the results were evaluated comparing with reference concrete. Three series concrete were produced. GBFS, BA and GBFS+BA are replaced the 3–7 mm-sized aggregate. Five test groups were constituted with the replacement percentages as 10%, 20%, 30%, 40% and 50% in each series. These by-products were used as non-ground form in the concrete. Durability properties of the concretes were compared in order to study the possible advantages of different replacement ratios. According to results, GBFS and BA affects some durability properties of concrete positively in case of it is used as fine aggregate. Resistance to high temperature and surface abrasion are positively affected properties. Capillarity, drying-wetting and freezing-thawing resistance of the concrete can be accepted to some extent. Properties of by-products and its replacement ratio are controlling the influence level and direction. Comparison of the SEM images and test results show that chemical and physical properties of GBFS and BA are the main factors affecting the concrete durability. It is concluded that it is possible to produce durable concrete by using GBFS and BA as fine aggregate.     

The production of fuel from,and the thermal stability of,sunflower oil,corn oil,and canola oil

Frying of sunflower, corn, and canola oils was carried out for seven running days at 175°C in this study. Fatty acid composition, free fatty acid, viscosity, iodine value, peroxide value, density, pH, saponification value, refractive index, average molecular weight, color, and the higher heating value of these oils have been analyzed. While the contents of free fatty acid, viscosity, saponification value, peroxide value, and colors (red and yellow) increase with the frying times, the contents of average molecular weight, iodine value, pH, and the higher heating value decreased for all oils in this work. However, reduction in the higher heating value is relatively low. This work indicated that recycling as a fuel of these oils can make a major economic contribution.     

Whey protein nanoparticles prepared with desolvation with ethanol: Characterization,thermal stability and interfacial behavior

Whey protein isolate (WPI) nanoparticles were prepared by diluting an alkaline solution of protein in ethanol at concentrations varying between 50 and 80%. The nanoparticles were then immediately diluted in buffer. While the nanoparticles were not stable at pH 7, they showed no changes in size when diluted at pH 3. When 75–80% ethanol was added during preparation, the size of the WPI nanoparticles ranged between 10 and 100 nm, with no change in size after dilution and storage at pH 3 for 96 h at 22 °C. When heating was applied, particle aggregation occurred, and large aggregates (>1 μm) were observed at temperatures > 60 °C. The particle size of the heat-induced aggregates could be reduced by homogenization. The nanoparticles prepared by desolvation showed interfacial pressure values similar to those of the corresponding protein solutions, indicating similar interfacial properties and the potential to be used to stabilize emulsions but as supramolecular aggregates of WPI.     

Determining the best type of heat exchangers for heat recovery

It is a common problem to choose the most appropriate heat exchanger configuration for heat recovery. In this study, a new model has been developed for determining the area and type of the most appropriate waste heat recovery heat exchanger for maximum net gain. A non-dimensional E number has been defined based on known technical and economic parameters such as the life-time, unit area cost of the heat exchanger, lower heating value of the fuel, overall heat transfer coefficient of heat exchanger, boiler efficiency, operation time per year, heat exchanger effectiveness, ratio of heat capacities, annual variation of the temperature of fluids supplied to the heat exchanger and present worth factor. The non-dimensional E numbers has been demonstrated in graphical forms as a function of NTU and ratio of heat capacities and corresponding heat exchanger area giving maximum net gain can easily be obtained from these graphs. The best heat exchanger type and its area can be determined comparing net gains or effectiveness of heat exchangers at NTU_max. Application of the new method has been given with a case study as a sample calculation.