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Developed Methodology (developed + methodology)
Selected AbstractsAn advanced methodology for steady-state security assessment of power systemsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2001D. P. Popovic The basic objective of this paper is to present the relevant aspects of an advanced methodology for steady-state security assessment of power systems. This methodology consists of the following relevant parts: procedure for forming the unified external network equivalents, with adaptive buffer system selection, procedure for fast contingency selection and simple method for the fast and sufficiently accurate assessment of dynamic variation of power system frequency during the time of its primary control. For the potentially critical contingency, the continuation of iterative procedure is performed. Full contingency analysis is based on specially developed method, which enables successive solution of the load-flow problem for a set of characteristic post-dynamic quasi-stationary states. The characteristics of the developed methodology are tested on the example of the existing electric power interconnection in the Balkans. [source] A Solvent-Assisted Compression Molded of Poly(L -lactide)/Hydroxyapatite Electrospun Fibers for Robust Engineered Scaffold SystemsMACROMOLECULAR MATERIALS & ENGINEERING, Issue 10 2009Nguyen Dang Luong Abstract In an attempt to enhance the biocompatibility and mechanical strength of fibrous polymeric scaffold systems, nanocrystalline hydroxyapatite (HAp) particles were incorporated into the electrospun poly(L -lactide) (PLLA) fibers and then mechanically interlocked using a vapor-phase solvent adsorption method. The solvent-assisted compression molding substantially increased the tensile strength (from 4.61 to 12.63 MPa) and mechanical modulus (from 50.6 to 627.7 MPa) of the fibrous scaffold, which maintained the interstitial space between the fibers to allow the facile transport of nutrients and waste during cell growth and polymer biodegradation. Macrometer-sized pores (ca. 100,400,µm) were introduced into the scaffolds in a controlled fashion using the salt leaching/gas forming technique to give desired space for a facile cell implantation and growth. Overall, the developed methodology allows the polymer-based scaffold systems to be tailored for various applications in light of surface characteristics, mechanical strength, and pore size of engineered scaffolds. [source] Desorption electrospray ionization mass spectrometric analysis of organophosphorus chemical warfare agents using ion mobility and tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2010Paul A. D'Agostino Desorption electrospray ionization mass spectrometry (DESI-MS) has been applied to the direct analysis of sample media for target chemicals, including chemical warfare agents (CWA), without the need for additional sample handling. During the present study, solid-phase microextraction (SPME) fibers were used to sample the headspace above five organophosphorus CWA, O -isopropyl methylphosphonofluoridate (sarin, GB), O -pinacolyl methylphosphonofluoridate (soman, GD), O -ethyl N,N -dimethyl phosphoramidocyanidate (tabun, GA), O -cyclohexyl methylphosphonofluoridate (cyclohexyl sarin, GF) and O -ethyl S-2-diisopropylaminoethyl methyl phosphonothiolate (VX) spiked into glass headspace sampling vials. Following sampling, the SPME fibers were introduced directly into a modified ESI source, enabling rapid and safe DESI of the toxic compounds. A SYNAPT HDMSÔ instrument was used to acquire time-aligned parallel (TAP) fragmentation data, which provided both ion mobility and MSn (n,=,2 or 3) data useful for the confirmation of CWA. Unique ion mobility profiles were acquired for each compound and characteristic product ions of the ion mobility separated ions were produced in the TriwaveÔ transfer collision region. Up to six full scanning MSn spectra, containing the [M,+,H]+ ion and up to seven diagnostic product ions, were acquired for each CWA during SPME fiber analysis. A rapid screening approach, based on the developed methodology, was applied to several typical forensic media, including Dacron sampling swabs spiked with 5,µg of CWA. Background interference was minimal and the spiked CWA were readily identified within one minute on the basis of the acquired ion mobility and mass spectrometric data. Copyright © 2010 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. [source] Flocculation Monitoring: Focused Beam Reflectance Measurement as a Measurement ToolTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2002A Blanco Abstract A methodology to study flocculation processes and floc properties using a non-imaging scanning laser microscope is presented in this paper. This methodology allows us to study floc stability and resistance to shear forces, re-flocculation tendency and reversibility of the flocs. Furthermore, optimal dosage of any polymer and the associated flocculation mechanism can be determined. In order to illustrate the technique, some examples applied to flocculation in papermaking are described. Although in this paper all the examples have been applied to papermaking, the developed methodology can be used in any process in which flocculation phenomena is involved. On présente dans cet article une méthode pour étudier les procédés de floculation à l'aide d'un microscope laser à balayage sans imagerie. Cette méthode permet d'étudier la stabilité des flocs et leur résistance aux contraintes de cisaillement, la tendance à la refloculation et la réversibilité des flocs. De plus, on peut déterminer le dosage optimal de tout polymère et le mécanisme de floculation associé. Pour illustrer cette technique, quelques exemples appliqués à la floculation dans la fabrication du papier sont décrits. Cependant, même si dans cet article tous les exemples s'appliquent à la fabrication du papier, la méthodologie peut s'appliquer à tout procédé comportant des phénomènes de floculation. [source] Multiresidue determination of antibiotics in aquaculture fish samples by HPLC,MS/MSAQUACULTURE RESEARCH, Issue 9 2010Consuelo Cháfer-Pericás Abstract An analytical method based on HPLC with MS/MS detection was developed and optimized in order to determine the most useful antibiotics (sulphonamides and tetracyclines) used in aquaculture. A simple extraction procedure, without any clean-up step, was evaluated in order to obtain maximum analyte recovery from fish samples (Sparus aurata). A mixture of methanol:water 70:30 (v/v)+1 mL EDTA 0.1 M was selected as optimum extractant solution. Because no matrix effects were observed, a standard calibration curve prepared in mobile phase was used for quantification purposes. Antibiotic-free fish samples were spiked at different concentration levels and analysed by the optimized HPLC method. The average recoveries (n=6) obtained were satisfactory, ranging from 88% to 110% at 100 ,g kg,1. The proposed methodology provided limits of detection for the tested antibiotics in the 1.2,16 ,g kg,1 range, lower than 100 ,g kg,1, the maximum residue level established by the European Union. Finally, commercial fish samples from different origins were analysed in order to confirm the usefulness of the developed methodology. [source] | ||||||||||