Heat transfer in a gas fluidized bed assisted by an alternating electric field

The application of an alternating electric field to cause movement of particles charged naturally by contact electrification in a fluidized bed, has be     

Midpoint potentials of the mitochondrial cytochromes of Crithidia fasciculata

The midpoint potentials of the mitochondrial respiratory chain cytochromes of the protozoan Crithidia fasciculata at pH 7.2, Em7.2, show great similarity to those measured in higher organisms. Values of Em7.2 for cytochromes a and a3 are +165 and +340 mV. Both c cytochromes have Em7.2 = +230 mV. There are two b cytochromes with the same spectral characteristics with Em7.2 = -20 and -135 mV. These values are compatible with two sites of energy conservation for oxidative phosphorylation in these mitochondria. All cytochrome components show potentiometric titrations with n = 1. There is a fluorescent flavoprotein in these mitochondria with Em7.2 = -40 mV and n =2, whose function is not known.     

Performance of everyday actions in mild Alzheimer's disease.

Early neuropsychological deficits associated with mild Alzheimer's disease (AD) have been characterized as memory deficits and impaired executive function or attention. The functional impact of early impairment was investigated by evaluating performance of everyday actions in older adults with mild AD (n = 15) as compared with healthy age-matched controls (n = 16). Everyday actions were familiar activities, for example, making a cup of tea, but were varied in complexity (simple, complex) and were performed under varied attention demand (single task, dual task). Although both participant groups responded to increasing task complexity by making more errors, the AD group made more errors under dual-task conditions regardless of the complexity of the task. Furthermore, a task requiring strategic retrieval of semantic information from long-term memory and manipulation of attention online (category fluency) was able to account for a large proportion of the group-related variance in everyday task performance. Results are discussed in relation to the role of components of working memory in performance of everyday actions in mild AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Biofilms in an urban water distribution system: measurement of biofilm biomass, pathogens and pathogen persistence within the Greater Stockholm Area, Sweden.

Distribution pipe biofilms can provide sites for the concentration of a wide range of microbial pathogens, thereby acting as a potential source of continual microbial exposure and furthermore can affect the aesthetic quality of water. In a joint project between Stockholm Water, the MISTRA "Sustainable Urban Water" program, the Swedish Institute for Infectious Disease Control and the Royal Technical University, Stockholm, the aim of the current study was to investigate biofilms formed in an urban water distribution system, and quantify the impact of such biofilms on potential pathogen accumulation and persistence within the Greater Stockholm Area, Sweden. When used for primary disinfection, ultra-violet (UV) treatment had no measurable influence on biofilm formation within the distribution system when compared to conventional chlorination. Biofilms produced within a model pilot-plant were found to be representative to those that had formed within the larger municipal water distribution system, demonstrating the applicability of the novel pilot-plant for future studies. Polystyrene microspheres (1.0 microm) and Salmonella bacteriophages demonstrated their ability to accumulate and persist within the model pilot-plant system, where the means of primary disinfection (UV-treatment, chlorination) had no influence on such phenomena. With the exception of aeromonads, potential pathogens and faecal indicators could not be detected within biofilms from the Stockholm water distribution system. Results from this investigation may provide information for water treatment and distribution management strategies, and fill key data gaps that presently hinder the refinement of microbial risk models.     

Intensity-modulated, stepped frequency cw lidar for distributed aerosol and hard target measurements

A compact frequency-modulated, continuous wave (FM-cw) lidar system for measurement of distributed aerosol plumes and hard targets is presented. The system is based on intensity modulation of a laser diode and quadrature detection of the return signals. The advantages of using laser diode amplitude modulation and quadrature detection is a large reduction in the hardware required for processing and storing return signals as well as the availability of off-the-shelf integrated electronic components from the wireless and telecommunication communities. Equations to invert the quadrature signal components and determine spatial distributions of multiple targets are derived. Spatial scattering intensities are used to extract aerosol backscatter coefficients, which can then be directly compared to microphysics aerosol models for environmental measurements. Finally, results from laboratory measurements with a monostatic FM-cw lidar system with both hard targets and aerosols are discussed.     

Synthesis and thiol–ene photopolymerization of (meth)allyl‐terminated polysulfides

Thiol‐terminated polysulfides (PS) are cured by mixing with an oxidant, resulting in limited shelf‐ and/or pot‐life, depending on whether formulated as a one‐ or two‐component system. Mixtures of thiol‐ and alkene‐terminated polysulfides offer the potential for an on‐demand curing process through thiol–ene photopolymerization. Thiol end groups of commercial polysulfides, PS‐1 (1000 g/mol) and PS‐2 (3000 g/mol), were converted to alkene by reaction with (meth)allyl bromide. Photopolymerizations were performed by irradiating films of equimolar thiol:ene mixtures at 320–500 nm (30 mW/cm²) in the presence of 5 wt % 2,2‐dimethoxy‐2‐phenyl‐acetophenone (DMPA). Reaction kinetics were measured using real‐time FTIR by monitoring absorbances at 3075 cm^?1 (alkene) or 2550 cm^?1 (thiol). In the absence of any reactive diluent, mixtures of thiol and alkene polysulfides failed to gel notwithstanding high reaction conversion (>90%). Partial or total replacement of the thiol polysulfide component with pentaerythritol tetrakis(3‐mercaptopropionate) (PETMP) yielded solid elastomeric films and ultimate reaction conversions of 80–96% after 5 min irradiation. Crosshatch adhesion measured on glass, aluminum, and steel was very poor (0B) for (meth)allyl PS‐1/PETMP and poor (2B) for (meth)allyl PS‐2/PETMP without adhesion promoters. (3‐Mercaptopropyl)trimethoxysilane (1 wt %) significantly improved adhesion of (meth)allyl PS‐2/PETMP on all substrates (4B) but yielded no improvement for (meth)allyl‐terminated PS‐1/PETMP. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45523.     

Synthesis and mechanical properties of poly(styrene-b-lsobutylene-b-styrene) block copolymer lonomers

Linear and three-arm star poly(styrene-b-isobutylene-b-styrene) (PS-PIB-PS) block copolymer ionomers possessing various counterions and levels of sulfonation were synthesized by sulfonating the polystyrene blocks of PS-PIB-PS block copolymers. Analysis of compression-molded films of the ionomers showed that the incorporation of sulfonate groups into the polystyrene blocks of these materials resulted in an increase in tensile strength, a decrease in elongation at break, and a persistence of elastic properties to much higher temperatures as compared with unsulfonated precursors. Among all counterions studied, zinc resulted in the strongest ionomers and potassium yielded the most easily processed ionomers. Dynamic mechanical analysis showed that the block copolymer ionomers possessed a phase-separated morphology; however, anomalous relaxations observed during the first heating cycle, but that were substantially reduced or completely absent in subsequent cycles, implied that strong ionic interactions were causing reduced processability and the formation of nonequilibrium morphologies. The observed relaxations were interpreted to be domain rearrangements brought about by the thermal energy supplied by the dynamic experiment. Annealing of films of relatively low ionic contents yielded viscoelastic behavior that was consistent with an equilibrium morphology characterized by phase-separated, partially sulfonated polystyrene domains of the same density and size as the polystyrene domains of the unsulfonated precursor. Compression molded films of high ionic content yielded a higher rubbery plateau modulus than the unsulfonated precursor, suggesting a different morphology. Solution-cast films of zinc ionomers exhibited two values for the rubbery modulus, a higher values at temperature below the T_g of polystyrene and a lower value at temperature above the T_g of polystyrene. Thermogravimetric analysis revealed the major mass-loss process of the parent, linear block copolymer at 417°C (mid-point) and of the tetramethyl ammonium ionomer at 431°C.     

Plasticization of poly(styrene-b-isobutylene-b-styrene) ionomers by acid salts of 2-ethylhexyl-p-dimethylaminobenzoate

Poly(styrene-b-isobutylene-b-styrene) block copolymer ionomer (overall molecular weight = 71,200 g/mole; 25.5 wt% polystyrene, 4.7% sulfonation of phenyl units, 100% neutralized with KOH) was compounded with various organic and inorganic acid salts of 2-ethylhexyl-p-dimethylaminobenzoate (ODAB) to explore the efficacy of these compounds as ionic plasticizers. Results were compared to the same polymer plasticized by zinc stearate. Plasticizers were added to the polymer at levels of ≈5 wt%. Films were prepared by solution casting from tetrachloroethylene. Thermogravimetric analysis (TGA) showed all ODAB derivatives to have lower decomposition temperatures than zinc stearate. Dynamic mechanical analysis (DMA) of the films showed varying degrees of ionic plasticization as evidenced by a lowering of the temperature at which the onset of flow occurred. With the exception of the stearic acid salt of ODAB, all ODAB derivatives were more efficient ionic plasticizers than zinc stearate. Among the ODAB derivatives, the degree of ionic plasticization varied, with the methane sulfonic and p-toluene sulfonic acid salts being most effective, leading to the conclusion that processing temperatures could be tailored to specific applications by choice of plasticizer and level of incorporation.     

Whole body scanning as a tool for clothing sizing: effects on women’s body satisfaction

Abstract

Whole-body scanning is increasingly used in the clothing industry, including in large-scale sizing surveys and virtual fitting. However, the impacts of 3D scanning on women’s body satisfaction are unclear as no previous studies have investigated impacts in a controlled experiment. This experiment investigated any causal effect of 3D whole-body scanning, as used in clothing applications, on women’s body satisfaction. Seventy women aged 18–35?years completed body image measures at baseline, immediately post-test, and two weeks later. At post-test relative to controls and controlling for baseline scores, women randomly allocated to the scanner condition scored significantly higher on Body Areas Satisfaction and significantly lower on Self-classified Weight, and positive effects persisted two weeks beyond the experimental session. Results suggest that whole-body scanning may improve women’s body satisfaction and reduce perceived overweight relative to controls, though further research is necessary to examine the reliability of this effect and underlying mechanisms.