The Shared Benefits of Data Administration

More than just a regulatory body, the data administration group is responsible for planning and promoting the use of information resources. By managing the corporate data base effectively, data administration provides benefits to everyone who depends on the use of accurate information.     

Kinetics of emitted mass—A study with three dry powder inhaler devices

The purpose of this study was to understand the kinetics of emptying of micronised salbutamol sulphate (SS) and lactohale 300 (LH300) under varying air flow rates (30–180 L min⁻¹) from three dry powder inhaler devices, Rotahaler^® (RH), Monodose Inhaler^® (MI) and Handihaler^® (HH). Aerosol concentration vs. time profiles, determined through real-time laser diffraction particle sizing, demonstrated that the majority of the powder from RH was emitted within one second while a more prolonged aerosolisation was observed from MI and HH. Peak aerosol concentrations were achieved more rapidly from RH compared to MI for both SS and LH300. Calculated cumulative emitted mass (CCEM) vs. time profiles were obtained from the aerosol concentration vs. time profiles and the emitted mass and the rate of CCEM (k_CCEM), estimated from a modelling approach, increased with increasing air flow rates. The k_CCEMvs. air flow rate profiles of SS and LH300 were significantly different at high air flow rates. The k_CCEM was highest from RH and lowest from MI. Differences in k_CCEM between the devices were related to capsule aperture size while the differences between the materials were due to the powder bed structure. This approach provided an understanding of the rate at which powder mass emptied from dry powder inhaler devices and was proposed to be a powerful development tool for the future powder inhalers.     

Indole‐based polymer and its silver nanocomposite as advanced antibacterial agents: synthetic path,kinetics of polymerization and applications

Atom transfer radical polymerization of 1‐allylindole‐3‐carbaldehyde (AIC) was studied by employing 2‐bromoisobutyryl bromide as initiator in toluene. It led to controlled radical polymerization of AIC, with an increase of molecular weight along with the conversion of the monomer, and a relatively narrow molar mass distribution was obtained, as determined by gel permeation chromatography. The living nature of poly(1‐allylindole‐3‐carbaldehyde) (PAIC) was confirmed by the chain extension polymerization whereas ¹H NMR analysis showed that the major population of PAIC retained the chain‐end functional group. PAIC and its silver nanocomposite were found to be biologically active against some tested bacterial pathogens. Minimum inhibitory concentration tests revealed that PAIC exhibited antibacterial activity against Staphylococcus aureus, Proteus mirabilis and Klebsiella pneumonae whereas PAIC/Ag nanocomposite showed antibacterial activity against Enterococcus faecalis and K. pneumonae. © 2012 Society of Chemical Industry     

N,N‐dichloro poly(styrene‐co‐divinyl benzene) sulfonamide polymeric beads: An efficient and recyclable decontaminating reagent for O,S‐diethyl methyl phosphonothiolate,a simulant of VX

An efficient and operationally simple method is developed for chemical decontamination of simulant of VX. A new chlorine bearing reagent N,N‐dichloro poly(styrene‐co‐divinyl benzene) sulfonamide was developed to deactivate the simulant of VX in aqueous medium. This decontamination reaction was monitored by gas chromatography (GC), and the products were analyzed by gas chromatography‐mass spectrometry (GC‐MS). This reagent has advantage over earlier reported reagents in terms of effectiveness, stability, nontoxicity, cost, ease of synthesis, recyclablity (collected after filtration, rechlorinated, and used for further reaction), and decontamination of simulant of VX to give single nontoxic product at room temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Compositional and structural analysis of RF magnetron sputtered La3+-modified PZT thin films

In the present work, we report the preparation of lanthanum-modified lead zirconate titanate (PLZT) thin films in pure perovskite phase by RF magnetron sputtering. For this purpose, a 3-in. diameter target of PLZT (8/60/40) was prepared by conventional solid-state reaction route. The chemical composition of PLZT target was determined using gravimetric analysis followed by UV–vis and flame atomic absorption spectrometry. Various deposition parameters such as target-to-substrate spacing, deposition temperature, post-deposition annealing temperature and time have been optimized to obtain PLZT films in pure perovskite phase. The films prepared in pure argon at 100 W RF power without external substrate heating exhibited pure perovskite phase after rapid thermal annealing (RTA) as confirmed by X-ray diffraction (XRD). Compositional analysis of the PLZT film was performed by secondary ion mass spectroscopy (SIMS) using PLZT target as standard sample. Depth profile of the film shows very good stoichiometric uniformity of all elements of PLZT.     

Transient-enhanced diffusion in shallow-junction formation

Shallow junctions are formed in crystalline Si by low-energy ion implantation of B⁺, P⁺, or As⁺ species accompanied by electrical activation of dopants by rapid thermal annealing and the special case of spike annealing. Diffusion depths were determined by secondary ion-mass spectroscopy (SIMS). Electrical activation was characterized by sheet resistance, Hall coefficient, and reverse-bias diode-leakage measurements. The B⁺ and P⁺ species exhibit transient-enhanced diffusion (TED) caused by transient excess populations of Si interstitials. The electrically activated fraction of implanted dopants depends mainly on the temperature for B⁺ species, while for P⁺ species, it depends on both temperature and P⁺ dose. The relatively small amount of diffusion associated with As⁺ implants is favorable for shallow-junction formation with spike annealing.     

Moisture absorption studies of fluorocarbon films deposited from pentafluoroethane and octafluorocyclobutane plasmas

The moisture absorption and diffusion characteristics of fluorocarbon films deposited from pentafluoroethane (PFE) and octafluorocyclobutane C₄F₈ plasmas are presented. The moisture absorption studies were carried out using a quartz crystal microbalance in a controlled environment. X-ray photoelectron spectroscopy and Fourier transform infrared (IR) spectroscopy were used to monitor the changes in bulk and surface chemical structure and composition of the deposited films. The equilibrium moisture uptake at relative humidity >90% was lower than 0.13 wt.% for films deposited from PFE or C₄F₈ monomers. Humidity cycling measurements showed no moisture chemisorption in the deposited films. Attenuated total reflectance infrared spectroscopy (ATR-IR) spectra of the deposited films indicated negligible change in the bulk composition of the deposited films. The estimated diffusivities of water in the deposited fluorocarbon films were of the order of 10⁻¹⁰ cm²/sec, and films deposited from C₄F₈ monomer showed higher diffusivity as compared to films deposited from PFE monomer. The equilibrium moisture uptake is affected by the presence of polar groups, the F/C ratio, and the O/C ratio. The relatively high diffusivity of water in the fluorocarbon films is attributed to the lack of polar groups in the deposited films. Adsorption onto the surface followed by diffusion into the bulk is proposed as the mechanism for moisture absorption in the fluorocarbon films. Finally, the moisture uptake of the fluorocarbon and hydrofluorocarbon films is compared to that of a conventionally used microelectronic polymer, polyimide (PI 2611), in order to evaluate the effect of polar groups and fluorine content on diffusion and equilibrium moisture uptake.     

Hollow Silica Spheres of Controlled Size and Porosity by Sol—Gel Processing

A new technique particularly suitable for fabricating uniform, hollow silica spheres of controlled size and porosity is described. The technique, which combines sol—gel processing with a hollow-drop generation technique, consists of producing a continuous stream of uniform, hollow drops of a tetraethyl orthosilicate solution and then converting the drops into a rigid form by exposing them to an ammoniated vapor gelation medium. The parameters controlling the properties of the resulting silica spheres are the detailed chemical makeup of the reactant solution and the gelation medium, and the dimensions and relative positions of the nozzles used for drop generation.     

Simulation of single phase non-Newtonian flow characteristics of heavy crude oil through horizontal pipelines

The effect of diameter, velocity, and temperature on flow properties of heavy crude oil in three horizontal pipelines using computational fluid dynamics (CFD) was studied. The flow characteristics were simulated by using CFD software, ANSYS Fluent 6.2. The mesh geometry of the pipelines having inner diameter of 1, 1.5, and 2 inch were created by using Gambit 2.4.6. From grid independent study, 221, 365 mesh sizes were selected for simulation. The CFD ANSYS Fluent 6.2 Solver predicted the flow phenomena, pressure, pressure drop, wall shear stress, shear strain rate, and friction factor. A good agreement between experimental and CFD simulated values was obtained.     

Numerical modeling of corrosion pit propagation using the combined extended finite element and level set method

A sharp-interface Eulerian formulation for modeling the propagation of localized pitting corrosion is presented. This formulation allows for an accurate representation of the corrosion front independent of the underlying finite element mesh and handles complex morphological transitions such as pit merging without requiring remeshing or mesh-moving procedures. First, the governing equations of the moving interface problem associated with pit growth are derived for the two-phase (metal-solution) system. Next, the implementation of the combined extended finite element and level set method and the procedure to enforce interface conditions are discussed. Finally, the method is validated by conducting several benchmark numerical studies, and comparing the results with published experimental data and existing numerical studies. Simulation studies indicate that: during diffusion-controlled corrosion an isolated pit grows as a semi-circular shape, whereas closely spaced pits merge and grow into an elongated elliptical shape; and only during activation-controlled corrosion the initial pit morphology is preserved.