A Critical Analysis of the Ethnography of Krannert Art Museum

This project evaluates the activity systems (composed of community, rules, division of labor, tools, subject, and motives) in the Krannert Art Museum as seen through its mission statement. It focuses on the evolution of the mission statement, how it should be interpreted, the exact motives behind the statement, what challenges it presents to the museum, and its involvement within the community. On the basis of interviews and archival, literature, and internet research, the authors find that the mission statement???s main goal is to provide a guide for the inner activities of the museum. Its connection to the community appears to be of primary importance.unpublishe

Facile synthesis and immobilization of Ag–TiO 2 nanoparticles on electrospun PU nanofibers by polyol technique and simple immersion

A simple polyol process is presented here to synthesize silver (Ag) nanoparticles (NPs) on titanium nanosphere substrate (Ag-TiO 2), which are subsequently decorated on the surface of electrospun polyurethane (PU) nanofibers by immersion in hot colloidal solution. Various spectroscopic and physical characterization techniques are utilized to study the physico-chemical properties of the prepared samples. The polyol-synthesized Ag-TiO 2 decorated PU nanofibers show superior antibacterial properties under UV light, and are potentially useful for water filtration application. © 2012 Elsevier B.V. All rights reserved

Antibacterial and superhydrophilic electrospun polyurethane nanocomposite fibers containing tourmaline nanoparticles

This paper describes a one-step fabrication of tourmaline (TM) nanoparticles (NPs)-decorated polyurethane (PU) composite nanofibers with superhydrophilic and antibacterial properties. The physico-chemical properties of the prepared samples were characterized by different characterization techniques. FESEM and TEM images confirmed the presence of well-dispersed TM NPs in/on PU nanofibers. The incorporation and homogeneous dispersion of 3. wt% TM NPs in PU exhibited an increase in tensile strength and modulus of 75% and 87%, respectively from those of the neat PU. All TM/PU composite mats showed improved hydrophilicity compared to neat PU mat, and a superhydrophilic surface with a contact angle of 13° was obtained at 5. wt% TM content. FTIR spectra confirmed the interaction of TM NPs to PU matrix through hydrogen bonding. Bacterial tests showed high zone inhibition for both Escherichia coli (Gram-negative) and Enterococci (Gram-positive) using the TM/PU composite mats with increasing efficiency as with the increase of TM NP content. The present TM/PU composite mat, which has improved mechanical properties, superhydrophilic surface, and good antibacterial properties, may be a potential candidate as an antibacterial material, in the field of health-protection textile and water filtration. © 2012 Elsevier B.V

One-step fabrication of antibacterial (silver nanoparticles/poly(ethylene oxide)) - Polyurethane bicomponent hybrid nanofibrous mat by dual-spinneret electrospinning

The one-step electrospinning fabrication of novel materials with added functionalities is being widely studied because of their wide array of applications. Here, the fabrication of a hybrid, bimodal nanofibrous mat made of two polymeric nanofibers: polyurethane (PU) and silver (Ag) nanoparticle (NP) - in situ - decorated poly(ethylene oxide) (PEO) utilizing an angled dual-spinneret electrospinning system is reported. Silver nitrate (AgNO 3) is in-situ reduced in high-molecular weight PEO, and Ag NPs with sizes from 6 to 90 nm as checked by scanning electron microscoy and transmission electron microscopy, are subsequently formed on the surface of PEO nanofibers depending on the reduction time. Successful fabrication of bicomponent polymer matrices (PU and PEO) in the hybrid mat is confirmed by Fourier transform infrared spectroscopy. Metallic Ag NPs are verified to be present in the hybrid mats by energy dispersive X-ray spectroscopy and ultraviolet-vis spectroscopy, showing plasmon resonance band peaks at 415 and 425 nm. The hybrid nanofibrous mat containing Ag NPs with an average size of 8 nm (i.e., reduction time of 3 h) exhibits strong antibacterial activity. © 2012 Elsevier B.V. All rights reserved

Assessing the effect of catalytic materials on the scaling of carbon steel

The present study investigated the efficacy of catalytic materials, i.e., tourmaline, zinc and aluminum, in mitigating calcium carbonate scaling of carbon steel material. Artificial hard water (480 ± 20. mg/l) was used to re-circulate in the system loop for 3. days of fouling test. Tests were carried out at various solution temperatures (27, 40, and 70. °C) and flow rates (800, 1200, and 1600. ml/min). Different measurements and characterization methods were carried out. The results showed consistently lower deposition of scales when the catalytic materials were incorporated in the system (i.e., treatment case), with as much as 21% reduction compared to the no-treatment case, depending on the solution temperature and flow rate. There was more corrosion activity observed in the no-treatment case compared to the treatment case. Furthermore, the scales at the no-treatment case showed pointed, sea-urchin-like structure, while those of the treatment case were dull, star-like structures and with thicker crystals than those at no-treatment case. In this study, we have shown the potential of catalytic materials in reducing scaling formation on non-heated carbon steel surface. © 2013 Elsevier B.V

Efficacy of zinc and tourmaline in mitigating corrosion of carbon steel in non-flow mode

Laboratory corrosion immersion tests were carried out to investigate the effectiveness of a physical water treatment (PWT) using zinc and ceramic tourmaline-based catalytic materials for the control of carbon steel corrosion in acidic still water (i.e., pH 4.5-5). The tests were carried out at different water temperatures over 168 h. Our results showed a maximum of 22 % reduction in the corrosion rate using PWT in comparison with the control case. Furthermore, the corrosion products depicted more agglomerated particles after the PWT treatment. In both cases, differences were observed in the crystal structures, showing in general lower corrosion activity when PWT was used. The present results could find potential applications in water distribution systems and where metallic materials are exposed to stagnant acidic water. © 2013 Institute of Chemistry, Slovak Academy of Sciences

Antibacterial tourmaline nanoparticles/polyurethane hybrid mat decorated with silver nanoparticles prepared by electrospinning and UV photoreduction

In this study, tourmaline (TM) nanoparticles (NPs) were incorporated in a polyurethane (PU) matrix by electrospinning and silver (Ag) nanoparticles in the form of wire-like structure were further decorated on the TM/PU nanofibrous mat by photoreduction under ultraviolet light irradiation. The incorporation of TM NPs has increased the conductivity of the solution, thus forming thinner fiber diameters compared to neat PU, but with improved tensile strength. Wire-like, agglomerated Ag NPs were decorated on the TM/PU matrix, and exhibited high bactericidal activity depending on the Ag content. The present antibacterial Ag/TM/PU hybrid mat has potential application in water treatment. © 2012 Elsevier B.V. All rights reserved

Characterization and mechanical performance comparison of multiwalled carbon nanotube/polyurethane composites fabricated by electrospinning and solution casting

Multiwalled carbon nanotube/polyurethane (MWNT/PU) composites were prepared by electrospinning and solution casting. The morphological and thermal properties, and mechanical performance of the nanofiber and film composites were characterized and compared. The tensile strength of neat PU film was 9-fold higher than that of neat PU nanofibrous mat. The incorporation of MWNTs increased the tensile strength and modulus of the composite nanofibers by 69% and 140%, respectively, and 62% and 78%, respectively for composite films. The MWNT/PU composites showed an improved thermal degradation behavior, with the incorporation of low MWNT content in the composites. © 2012 Published by Elsevier Ltd

Inactivation of bacteria in batch suspension by fluidized ceramic tourmaline nanoparticles under oscillating radio frequency electric fields

Here, we investigated the synergistic effect of fluidized ceramic tourmaline nanoparticles (NPs) with oscillating electric fields to the inactivation of Escherichia coli in batch suspension. Different amounts of tourmaline NPs (5-100 mg) were dispersed in bacterial suspension (50 ml) and oscillating radio frequency (RF) electric field was applied at 3 V (equivalent of 1.5 V/cm electric field strength) and at varying frequencies (100 kHz and 1 MHz). The results showed high inactivation efficiency when combining fluidized tourmaline NPs and oscillating electric fields as compared to individual treatments of electric fields or tourmaline NPs only. The results showed 2.5-5-log reduction of viable E. coli concentration depending on the tourmaline concentration, electric field frequency and solution temperature. The present method shows a lot of promise as a novel and low-cost bacterial inactivation technique for water treatment applications. © 2012 Elsevier Ltd and Techna Group S.r.l