Insights into structural difference between sodium polyacrylate PAA and sodium polymethacrylate PMA in salt solutions investigated by molecular simulations

Journal of Materials Science - The difference in the structural properties of highly charged polyacrylic acid (PAA) and polymethacrylic acid (PMA) is investigated by atomistic molecular dynamics...     

Sputter deposition of self-organized nanoclusters through porous anodic alumina templates

Silver nanoparticles were sputter deposited through self organized hexagonally ordered porous anodic alumina templates that were fabricated using a two-step anodization process. The average pore diameter of the template was 90 nm and the interpore spacing was 120 nm. Atomic force microscope studies of the sputter-deposited silver nanoparticle array on a Si substrate indicate an approximate replication of the porous anodic alumina mask. The nature of the deposition depends strongly on the process parameters such as sputtering voltage, ambient pressure and substrate temperature. We report a detailed study of the sputtering conditions that lead to an optimal deposition through the template.     

Phase separation in immiscible silver–copper alloy thin films

Far from equilibrium, immiscible nanocrystalline Ag–Cu alloy thin films of nominal composition Ag–40 at.% Cu have been deposited by co-sputter deposition. Both X-ray and electron diffraction studies indicate that the as-deposited films largely consist of nanocrystalline grains of a single alloyed face-centered cubic (fcc) phase. However, detailed three-dimensional atom probe tomography studies on the same films give direct evidence of a nanoscale phase separation within the columnar grains of the as-deposited Ag–Cu films. Subsequent annealing of these films at 200 °C leads to two effects; a more pronounced nanoscale separation of the Ag and Cu phases, as well as the early stages of recrystallization leading to the breakdown of the columnar grain morphology. Finally, annealing at a higher temperature of 390 °C for a long period of time leads to complete recrystallization, grain coarsening, and a complete phase separation into fcc Cu and fcc Ag phases.     

Backpropagation neural-network-based retrieval of atmospheric water vapor and cloud liquid water from IRS-P4 MSMR

A new multiparameter retrieval algorithm based on a backpropagation neural network (BPNN) has been developed for deriving integrated water vapor (WV) and cloud liquid water (CLW) contents over oceans from brightness temperatures (BTs) measured by the Multi-frequency Scanning Microwave Radiometer (MSMR) launched onboard Indian Remote Sensing satellite IRS-P4. The MSMR measures brightness temperatures in vertical and horizontal polarizations at 6.0-, 10.65-, 18.0-, and 21.0-GHz frequencies. The data are available at three spatial grid resolutions of 150, 75, and 50 km. In this paper, a BPNN has been trained using brightness temperatures simulated through radiative transfer model and simulated surface and atmospheric parameters. The present algorithm has been compared with the operational MSMR retrieval algorithm based on statistical regression using the same dataset. The validation of WV with in situ data (Vaisala radiosonde) is presented. Moreover, comparison of WV and CLW derived from MSMR using BPNN with the finished products from the Special Sensor Microwave/Imager and the Tropical Rainfall Measuring Mission Microwave Imager has also been carried out. The complexity of the BPNN in retrieval of geophysical products, individually and simultaneously, has also been discussed. Simultaneous retrieval of WV and CLW improves the results.     

Oxidation growth stresses in an alumina-forming ferritic steel measured by creep deflection

Deflection tests have been used to estimate the stresses developed in the alumina layer formed during short-term oxidation of a Fe-22Cr-5Al-0.3Y Fecralloy steel at 1000°C. Elastic analysis of the deflecting specimen is inappropriate under these test conditions because of the low creep strength of the alloy. Accordingly, a recent creep analysis has been used in this work using currently determined creep properties of the alloy substrate. The results of the analysis show that for the thin oxides produced (<1 m), the planar stress within the oxide layer is everywhere compressive. Average values are approximately 850 MPa after 0.5 hr oxidation but reduce to <200 MPa after 6.5 hr. These values are very much less than would be expected under conditions of elastic deformation.Reproduced by permission of the Controller of HMSO.     

Automatic room information retrieval and classification from floor plan using linear regression model

International Journal on Document Analysis and Recognition (IJDAR) - The automatic creation of a repository of the building’s floor plan helps a lot to the architects to reuse them. The basic...     

An outbreak of ammonia poisoning from chicken tenders served in a school lunch

Although foodborne outbreaks of illness are relatively common, they are rarely caused by chemical agents. An outbreak of gastrointestinal illness occurred among students at two schools shortly after lunch was served. A cohort study, an environmental investigation, and microbiological and toxicological laboratory testing of food samples were performed. A case was defined as a student or teacher who ate food prepared in the kitchen at school A on 25 November 2002 (and served at schools A and B) and who later developed headache or symptoms of gastrointestinal tract irritation, with onset within 180 min of eating lunch. Among 312 persons interviewed, 157 persons became ill (attack rate = 49%; attack rate 41% for school A, 11% for school B). Onset of illness occurred within 60 min for 81% of cases; 91% of students reported that their chicken tenders smelled unusual. Eating chicken tenders that smelled unusual was associated with being a case (relative risk 9.2, 95% confidence interval 1.4 to 62.6, P < 0.05). Ammonia was detected in uncooked chicken tenders at levels as high as 2,468 ppm. The chicken had been contaminated during a warehouse leak of ammonia refrigerant. This outbreak of ammonia poisoning is only the second reported in food, and the first in a solid food. Heated chicken tenders contaminated with ammonia can cause acute illness within a short period of time.     

Fabrication and characterization of tungsten and graphite based PFC for divertor target elements of ITER like tokamak application

The development of the fabrication technology of macro-brush configuration of tungsten (W) and carbon (graphite and CFC) plasma facing components (PFCs) for ITER like tokamak application is presented. The fabrication of qualified joint of PFC is a requirement for fusion tokamak. Vacuum brazing method has been employed for joining of W/CuCrZr and C/CuCrZr. Oxygen free high conductivity (OFHC) copper casting on W tiles was performed followed by machining, polishing and ultrasonic cleaning of the samples prior to vacuum brazing. The W/CuCrZr and graphite/CuCrZr based test mockups were vacuum brazed using silver free alloys. The mechanical shear and tensile strengths were evaluated for the W/CuCrZr and graphite/CuCrZr brazed joint samples. The micro-structural examination of the joints showed smooth interface. The details of fabrication and characterization procedure for macro-brush tungsten and carbon based PFC test mockups are presented.     

Designing Efficient Oxygen Scavenging Coating Formulations for Food Packaging Applications

Modified atmosphere packaging is widely used to prolong the shelf life of many oxygen‐sensitive items including food, pharmaceuticals, work of art and so on. For food packaging applications, we investigated the effectiveness of oxygen scavenging coatings and flexographic printing ink formulations made using water soluble and water insoluble ascorbate enzyme systems. The present study summarizes the effects of various parameters on the oxygen scavenging rates and other performance aspects of the formulations. It is shown that; the initial oxygen scavenging rate can be increased by increasing the surface area of Calcium Ascorbate crystals and addition of catalyst or edible oil; addition of a catalyst like TiO₂ or Alumina and an edible oil in Ascorbate and laccase‐based formulations induces a synergistic effect upon the rate of scavenging oxygen from the packages; an efficient oxygen scavenging coating formulation can be made using water soluble Calcium Ascorbate and insoluble Ascorbate Palmitate containing enzyme and substrate; designing an efficient oxygen scavenging formulation using water insoluble Ascorbate Palmitate can reduce or eliminate formation of effluent which has potential to change the aperral of food items inside the package; an adverse effect of some binders which cause a reduction in the oxygen scavenging rate can be eliminated by making blends of different binders. Copyright © 2013 John Wiley & Sons, Ltd.