Directory of Open Access Journals (Sweden)
Elena Bagryanskaya
2010-09-01
Full Text Available Thermal decomposition of alkoxyamines in the presence of scavengers was found to proceed with the formation of chemically induced nuclear polarization detected by 1H NMR. The distinctive Chemically Induced Dynamic Nuclear Polarization (CIDNP features were studied using the example of three alkoxyamines: 4-nitrophenyl 2-(2,2,6,6-tetramethylpiperidin-1-yloxy-2-methylpropanoate (1a, 4-nitrophenyl 2-(2,2-diphenyl-3-phenylimino-2,3-dihydroindol-1-yloxy-2-methylpropanoate (2a and 4-nitrophenyl 2-(2,2,5,5-tetramethyl-4-phenyl-2H-imidazol-1-oxy-2-methylpropanoate (3a in the presence of PhSH. The analysis of CIDNP signs of methacrylate protons allows us to conclude on the occurrence of hydrogen atom transfer reaction in geminate radical pair formed in alkoxyamine thermolysis. Thus, CIDNP is a fast and sensitive method to detect the occurrence of intra/intermolecular hydrogen transfer in alkoxyamine thermolysis.
Chemicals Derived from Biomass Thermolysis and Gasification
Energy Technology Data Exchange (ETDEWEB)
Schaidle, Joshua A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Talmadge, Michael S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Biddy, Mary J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nimlos, Mark R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bratis, Adam D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)
2017-07-14
The United States has the potential to sustainably produce over 1 billion dry tons of nonfood biomass per year by 2030. While conversion of this biomass into fuels has garnished significant attention, these renewable feedstocks can also be converted into valuable chemicals. Analogous to petroleum refining, the coproduction of fuels and chemicals from biomass enables more complete utilization of the feedstock and supports the growth of a bio-economy by improving biorefinery economics. This chapter provides an overview of biomass thermolysis and gasification technologies, highlights existing and future chemical production opportunities, and elaborates on specific challenges associated with product separation and purification.
Antitumor therapy using nanomaterial-mediated thermolysis.
Sawdon, Alicia; Weydemeyer, Ethan; Peng, Ching-An
2014-09-01
Nanomaterial-based systems present several novel therapeutic opportunities for cancer therapy based solely upon their unique physical and chemical properties. Despite advances in current cancer treatment, collateral damage to neighboring healthy tissues still cannot be avoided. By exploiting the strong optical and/or electromagnetic properties offered by nanomaterials, they are being employed as thermal nanoscalpels for the ablation of cancer cells. Through surface functionalization, these nanomaterials can be specifically targeted to tumorous tissue allowing for an increase in therapeutic potential and reduction in side effects. Moreover, these features provide nanomaterials with a tunable surface which can be used to modify optical, magnetic, thermal and mechanical properties. This review highlights carbon nanomaterials, nanogolds, magnetic nanoparticles and emerging hybrids applied for the thermolysis of cancer cells.
Solution Focused Approach and Usage of Nursing
Nurcan AKGÜL GÜNDOÐDU; Handan ZÝNCÝR; Nuran GÜLER
2016-01-01
"Problem talk creates problems; solution talk creates solutions " Steve de Shazer In recent years, concern for solution-oriented approach has increased in nursing practice. In this review it is aimed to give information about nursing application of solution-oriented approach whose efficacy has been proved with many studies. In addition, solution-oriented approach is what how it turned out, the answer to the question of principle, and that is what the management strategy and what the n...
Thermolysis kinetics and thermal degradation compounds of alliin.
Chen, Zixing; Xu, MingJiao; Wang, Chao; Zhou, Hua; Fan, Lokyee; Huang, Xuesong
2017-05-15
To investigate thermolysis kinetics and identify degradation compounds, alliin solutions were heated at 60, 80, and 89°C. The degradation compounds of alliin were identified by high performance liquid chromatography-mass spectrometry (HPLC-MS), tandem mass spectrometry (MS/MS) and ultra-pressure liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). The results showed that the thermal degradation kinetic of alliin could be described by a first-order reaction and k=4.38×1017exp (-142494/RT), where k is the reaction rate constant, min-1; R is gas constant; T is the absolute temperature, K. Degraded compounds, including S-allyl-l-cysteine and ethers, such as allyl alanine disulfide, allyl alanine trisulfide, allyl alanine tetrasulfide, dialanine disulfide (cysteine), dialanine trisulfide and dialanine tetrasulfide, were identified by HPLC-MS, MS/MS and UPLC-HRMS. Allyl alanine tetrasulfide was identified for the first time in alliin. The results show that alliin is unstable and significant numbers of organosulfur compounds are generated under high temperature treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Steam thermolysis of tire shreds: modernization in afterburning of accompanying gas with waste steam
Kalitko, V. A.
2010-03-01
On the basis of experience in the commercial operation of tire-shred steam thermolysis in EnresTec Inc. (Taiwan) producing high-grade commercial carbon, liquid pyrolysis fuel, and accompanying fuel gas by this method, we have proposed a number of engineering solutions and calculated-analytical substantiations for modernization and intensification of the process by afterburning the accompanying gas with waste steam condensable in the scrubber of water gas cleaning of afterburning products. The condensate is completely freed of the organic pyrolysis impurities and the necessity of separating it from the liquid fuel, as is the case with the active process, is excluded.
Solution Focused Approach and Usage of Nursing
Directory of Open Access Journals (Sweden)
Nurcan AKGÜL GÜNDOÐDU
2016-12-01
Full Text Available "Problem talk creates problems; solution talk creates solutions " Steve de Shazer In recent years, concern for solution-oriented approach has increased in nursing practice. In this review it is aimed to give information about nursing application of solution-oriented approach whose efficacy has been proved with many studies. In addition, solution-oriented approach is what how it turned out, the answer to the question of principle, and that is what the management strategy and what the nursing relationship will be sought. [JCBPR 2016; 5(3.000: 145-152
Unimolecular Gas-Phase Thermolysis of Ethyl Acetate
DEFF Research Database (Denmark)
Egsgaard, Helge; Carlsen, Lars
1983-01-01
The unimolecular gas-phase thermolysis of ethyl acetate has been investigated by the Flash-Vacuum-Thermolysis/Field-Ionization Mass Spectrometry (FVT/FI-MS) method in combination with Collision Activation (CA) mass spectrometry at 1253K. Two predominant reactions are observed: elimination...... of ethylene affording acetic acid, the latter to some extent consecutively yielding ketene, and intramolecular oxygen to oxygen ethyl group migration. Additionally minor amounts of acetaldehyde is formed. The mechanistic aspects are discussed based on 18O and 18O/ 13C labelling....
Urea thermolysis and NO{sub x} reduction with and without SCR catalysts
Energy Technology Data Exchange (ETDEWEB)
Fang, Howard L.; DaCosta, Herbert F.M. [Cummins Technology Center, Cummins Inc., MC 50183, 1900 McKinley Avenue, Columbus, IN 47201 (United States)
2003-10-31
Urea-selective catalytic reduction (SCR) has been a leading contender for removal of nitrogen oxides (deNO{sub x}) from diesel engine emissions. Despite its advantages, the SCR technology faces some critical detriments to its catalytic performance such as catalyst surface passivation (caused by deposit formation) and consequent stoichiometric imbalance of the urea consumption. Deposit formation deactivates catalytic performance by not only consuming part of the ammonia produced during urea decomposition but also degrading the structural and thermal properties of the catalyst surface. We have characterized the urea thermolysis with and without the urea-SCR catalyst using both spectroscopic (DRIFTS and Raman) and thermal techniques (thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC)) to identify the deposit components and their corresponding thermal properties. Urea thermolysis exhibits two decomposition stages, involving ammonia generation and consumption, respectively. The decomposition after the second stage leads to the product of melamine complexes, (HNC=NH){sub x}(HNCO){sub y}, that hinder catalytic performance. The presence of catalyst accompanied with a good spray of the urea solution helps to eliminate the second stage. In this work, kinetics of the direct reduction of NO{sub x} by urea is determined and the possibility of using additives to the urea solution in order to rejuvenate the catalyst surface and improve its performance will be discussed.
A Generic Solution Approach to Nurse Rostering
DEFF Research Database (Denmark)
Hansen, Anders Dohn; Mason, Andrew; Ryan, David
In this report, we present a solution approach to the nurse rostering problem. The problem is defined by a generic model that is able to capture close to all of the problem characteristics that we have seen in the literature and in the realistic problems at hand. The model is used directly in the...
Study of conversion of ammonia from urea water solution droplets using CFD
Jyothis, K.; Vikas, R.
2017-09-01
This paper deals with the numerical analysis of the spray behaviour of urea water solution (UWS) droplets used in Selective catalytic reduction (SCR) process. The study uses the ANSYS-Fluent-14 as a basic framework for numerical simulations. The evaporation modelling is based on multi-component droplet evaporation approach along with the consideration of Stefan flow. The urea decomposition treated as direct thermolysis approach, where the modelling is based on the single kinetic rate approach by the proper fitting of pre-exponent. This developed model was used for spray simulation of UWS droplet evaporation to determine the urea to ammonia conversion efficiency. The obtained spray simulation results were compared with the available experimental data. The comparison shows the pre-exponent developed in the study is suitable for direct thermolysis approach to get promising results in determining the ammonia conversion efficiency.
Heterogeneous nucleation in solutions: generalized Gibbs' approach.
Abyzov, Alexander S; Schmelzer, Jürn W P
2014-06-28
Heterogeneous nucleation in solutions on planar solid surfaces is modeled taking into account changes of the state parameters of the critical clusters in dependence on supersaturation. The account of the variation of the state parameters of the cluster phase on nucleation is performed in the framework of the generalized Gibbs' approach. A regular solution is chosen as a model for the analysis of the basic qualitative characteristics of the process. It is shown that, employing the generalized Gibbs approach, contact angle and catalytic activity factor for heterogeneous nucleation become dependent on the degree of metastability (supersaturation) of the solution. For the case of formation of a cluster in supersaturated solutions on a surface of low wettability (the macroscopic equilibrium contact angles being larger than 90°), the solid surface has only a minor influence on nucleation. In the alternative case of high wettability (for macroscopic equilibrium contact angles being less than 90°), nucleation is significantly enhanced by the solid surface. Effectively, the existence of the solid surface results in a significant shift of the spinodal to lower supersaturations as compared with homogeneous nucleation. Qualitatively, the same behavior is observed now near the new (solid surface induced) limits of instability of the solution as compared with the behavior near to the spinodal curve in the case of homogeneous nucleation.
Spring Recipes A Problem-solution Approach
Long, Josh; Mak, Gary
2010-01-01
With over 3 Million users/developers, Spring Framework is the leading "out of the box" Java framework. Spring addresses and offers simple solutions for most aspects of your Java/Java EE application development, and guides you to use industry best practices to design and implement your applications. The release of Spring Framework 3 has ushered in many improvements and new features. Spring Recipes: A Problem-Solution Approach, Second Edition continues upon the bestselling success of the previous edition but focuses on the latest Spring 3 features for building enterprise Java applications.
Silverlight recipes a problem-solution approach
Ghosh, J
2010-01-01
Silverlight Recipes: A Problem-Solution Approach, Second Edition is your practical companion to developing rich, interactive web applications with Microsoft's latest technology. This book tackles common problems and scenarios that on-the-job developers face every day by revealing code and detailed solutions. You'll quickly be able to integrate real-world, functioning code into your applications-and save hours of coding time. The recipes included in Silverlight Recipes have been carefully selected and tested with the professional developer in mind. You'll find problems stated clearly and succin
Android Recipes A Problem-Solution Approach
Friesen, Jeff
2011-01-01
Android continues to be one of the leading mobile OS and development platforms driving today's mobile innovations and the apps ecosystem. Android appears complex, but offers a variety of organized development kits to those coming into Android with differing programming language skill sets. Android Recipes: A Problem-Solution Approach guides you step-by-step through a wide range of useful topics using complete and real-world working code examples. In this book, you'll start off with a recap of Android architecture and app fundamentals, and then get down to business and build an app with Google'
Kinetics and mechanism of thermolysis of dibenzyl ether
Energy Technology Data Exchange (ETDEWEB)
Korobov, V.Yu.; Grigorieva, E.N.; Senko, O.V.; Kalechitz, I.V.
1988-10-01
The kinetics of thermolysis of dibenzyl ether in tetralin have been studied at 350-410 degrees C in a hydrogen atmosphere at 8.5 MPa pressure. A kinetic model has been proposed that satisfactorily describes the process and takes into account both the known transformation of ethers into toluene and benzaldehyde and the direct destruction of ether to benzene and toluene with elimination of CO and secondary conversions of benzaldehyde. It has been shown that at lower temperatures the first reaction prevails whereas at higher temperatures both reactions become competitive. The kinetic parameters support an intramolecular rearrangement as a pathway of the first reaction and a radical mechanism as a pathway of the second. 16 refs., 4 figs., 1 tab.
Protonolysis and thermolysis reactions of functionalised NHC-carbene boranes and borates.
Arnold, Polly L; Bell, Nicola L; Marr, Isobel H; She, Siyi; Hamilton, Jonathan; Fraser, Craig; Wang, Kai
2014-11-07
A set of β-ketoimidazolium and β-ketoimidazolinium salts of the general formula [R(1)C(O)CH2{CH[NCR(3)CR(3)N(R(2))]}]X (R(1) = (t)Bu, naphth; R(2) = (i)Pr, Mes, (t)Bu; R(3) = H, Me, (H)2; X = Cl, Br) show contrasting reactivity with superhydride bases MHBEt3; two are reduced to chiral β-alcohol carbene-boranes R(1)CH(OH)CH2{C(BEt3)[NCR(3)CR(3)N(R(2))]} 2 (R(1) = (t)Bu; R(2) = (i)Pr, Mes; R(3) = H), two with bulky R(2) substituents are reduced to chiral β-borate imidazolium salts [R(1)CH(OBEt3)CH2{CH[NCR(3)CR(3)N(R(2))]}]X 3 (R(1) = (t)Bu, naphth; R(2) = Mes, (t)Bu; R(3) = H, Me; X = Cl, Br), and the two saturated heterocycle derivatives remain unreduced but form carbene-borane adducts R(1)C(O)CH2{C(BEt3)[NCR(3)CR(3)N(R(2))]} 4 (R(1) = (t)Bu, naphth; R(2) = Mes; R(3) = (H)2). Heating solutions of the imidazolium borates 3 results in the elimination of ethane, in the first example of organic borates functioning as Brønsted bases and forming carbene boranes R(1)CH(OBEt2)CH2{C[NCR(3)CR(3)N(R(2))]} 5 (R(1) = naphth; R(2) = Mes; R(3) = Me). The 'abnormal' carbene borane of the form 2 R(1)CH(OH)CH2{CH[NC(BEt3)CR(3)N(R(2))]} (R(1) = (t)Bu; R(2) = (t)Bu; R(3) = H), is also accessible by thermolysis of 3, suggesting that the carbene-borane alcohol is a more thermodynamically stable combination than the zwitterionic imidazolium borate. High-temperature thermolysis also can result in complete cleavage of the alcohol arm, eliminating tert-butyloxirane and forming the B-N bound imidazolium borate 7. The strong dependence of reaction products on the steric and electronic properties of each imidazole precursor molecule is discussed.
Properties of residual marine fuel produced by thermolysis from polypropylene waste
Directory of Open Access Journals (Sweden)
Linas Miknius
2015-06-01
Full Text Available Thermal degradation of waste plastics with the aim of producing liquid fuel is one of the alternative solutions to landfill disposal or incineration. The paper describes thermal conversion of polypropylene waste and analysis of produced liquid fuel that would satisfy ISO 8217-2012 requirements for a residual marine fuel. Single pass batch thermolysis processes were conducted at different own vapour pressures (20-80 barg that determined process temperature, residence time of intermediates what resulted in different yields of the liquid product. Obtained products were stabilized by rectification to achieve required standard flash point. Gas chromatography and 1H NMR spectrometry show aliphatic nature of the liquid product where majority of the compounds are isoalkanes and isoalkenes. Only lightest fractions boiling up to a temperature of 72 oC have significant amount of n-pentane. Distribution of aromatic hydrocarbons is not even along the boiling range. The fractions boiling at a temperature of 128 oC and 160 oC have the highest content of monocyclic arenes – 3.16 % and 4.09 % respectively. The obtained final liquid residual product meets all but one requirements of ISO 8217-2012 for residual marine fuels.DOI: http://dx.doi.org/10.5755/j01.ms.21.2.6105
Directory of Open Access Journals (Sweden)
2009-04-01
Full Text Available In this work, the formation of semiconductive Sb2S3 nanoparticles inside amorphous polystyrene has been achieved by thermal degradation of the corresponding antimony dodecyl-mercaptide, Sb(SC12H253. The thermolysis of the dodecyl-mercaptide precursor was studied as both pure phase and mercaptide solution in polystyrene. The thermal decomposition of the antimony mercaptide precursor at 350°C, under vacuum, showed the formation of a mixture of antimony trisulfide (stibnite, Sb2S3 and zero-valent antimony (Sb phase. X-ray Powder Diffraction (XRD and Rietveld analysis carried out on the obtained nanostructured powder confirmed the presence of Sb and Sb2S3 phases in 10.4 wt% and 89.6 wt% amount, respectively. The same pyrolysis reaction was carried out in the polymer and the resulting nanocomposite material was characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, UV-VIS spectroscopy, and fluorescence spectroscopy. The nanocomposite structural characterization indicated the presence of well-dispersed nanoclusters of antimony and stibnite (15–30 nm in size inside the amorphous polymeric phase. Optical measurements on the obtained nanocomposite films showed a strong emission at 432 nm upon excitation at 371 nm, probably related to the presence of Sb2S3 nanoclusters.
Pechenyuk, S. I.; Semushina, Yu. P.; Kuz'mich, L. F.; Ivanov, Yu. V.
2016-01-01
Acid-base properties of the products of thermal decomposition of [M(A)6] x; [M1(L)6] y (where M is Co, Cr, Cu, Ni; M1 is Fe, Cr, Co; A is NH3, 1/2 en, 1/2 pn, CO(NH2)2; and L is CN, 1/2C2O4) binary complexes in air and their catalytic properties in the oxidation reaction of ethanol with atmospheric oxygen are studied. It is found that these thermolysis products are mixed oxides of the central atoms of complexes characterized by pH values of the zero charge point in the region of 4-9, OH-group sorption limits from 1 × 10-4 to 4.5 × 10-4 g-eq/g, OH-group surface concentrations of 10-50 nm-2 in 0.1 M NaCl solutions, and S sp from 3 to 95 m2/g. Their catalytic activity is estimated from the apparent rate constant of the conversion of ethanol in CO2. The values of constants are (1-6.5) × 10-5 s-1, depending on the gas flow rate and the S sp value.
Rugate filter design: An analytical approach using uniform WKB solutions
Perelman, N.; Averbukh, I.
1996-03-01
An analytical approach to the design of rugate filters with a smooth amplitude modulation of the sine-wave index is developed. The approach is based on the uniform WKB solutions (asymptotic expansions) of the coupled-wave equations. A closed-form solution for the inverse problem (finding the refractive index profile for a given reflectance shape inside the stop band) is found.
Zielinski, Michal W; McGann, Locksley E; Nychka, John A; Elliott, Janet A W
2017-11-22
The prediction of nonideal chemical potentials in aqueous solutions is important in fields such as cryobiology, where models of water and solute transport-that is, osmotic transport-are used to help develop cryopreservation protocols and where solutions contain many varied solutes and are generally highly concentrated and thus thermodynamically nonideal. In this work, we further the development of a nonideal multisolute solution theory that has found application across a broad range of aqueous systems. This theory is based on the osmotic virial equation and does not depend on multisolute data. Specifically, we derive herein a novel solute chemical potential equation that is thermodynamically consistent with the existing model, and we establish the validity of a grouped solute model for the intracellular space. With this updated solution theory, it is now possible to model cellular osmotic behavior in nonideal solutions containing multiple permeating solutes, such as those commonly encountered by cells during cryopreservation. In addition, because we show here that for the osmotic virial equation the grouped solute approach is mathematically equivalent to treating each solute separately, multisolute solutions in other applications with fixed solute mass ratios can now be treated rigorously with such a model, even when all of the solutes cannot be enumerated.
Heuristic Solution Approaches to the Double TSP with Multiple Stacks
DEFF Research Database (Denmark)
Petersen, Hanne Løhmann
2006-01-01
This paper introduces the Double Travelling Salesman Problem with Multiple Stacks and presents a three different metaheuristic approaches to its solution. The Double Travelling Salesman Problem with Multiple Stacks is concerned with finding the shortest route performing pickups and deliveries...
Heuristic Solution Approaches to the Double TSP with Multiple Stacks
DEFF Research Database (Denmark)
Petersen, Hanne Løhmann
This paper introduces the Double Travelling Salesman Problem with Multiple Stacks and presents a three different metaheuristic approaches to its solution. The Double Travelling Salesman Problem with Multiple Stacks is concerned with finding the shortest route performing pickups and deliveries...
Java EE 7 recipes a problem-solution approach
Juneau, Josh
2013-01-01
Java EE 7 Recipes takes an example-based approach in showing how to program Enterprise Java applications in many different scenarios. Be it a small-business web application, or an enterprise database application, Java EE 7 Recipes provides effective and proven solutions to accomplish just about any task that you may encounter. You can feel confident using the reliable solutions that are demonstrated in this book in your personal or corporate environment. The solutions in Java EE 7 Recipes are built using the most current Java Enterprise specifications, including EJB 3.2, JSF 2.2, Expression La
Pathways in coal thermolysis: a theoretical and experimental study with model compounds
Energy Technology Data Exchange (ETDEWEB)
Ekpenyong, I.A.; Virk, P.S.
1982-01-01
Fundamental aspects of coal thermolysis were investigated, including how the chemical structures of aromatics, hydroaromatics, and alcohols affect their reactivities as hydrogen donors and acceptors in coal processing. The susceptibilities of substructural entities in coals to fragmentation via a number of thermal pericyclic and free radical mechanisms were probed, as were the factors governing relative reactivities within series of such coal model compounds. The theoretical part of the work applied perturbation molecular orbital (PMO) and frontier orbital theories, in conjunction with ..pi..- and pseudo-..pi.. MO's, to the study of model compound reactivity. This enabled prediction of reactivity patterns of H-donors, H-acceptors and coal-like structures as functions of their ..pi..- and sigma-bond configurations, including heteroatomic effects. Experimentally, the liquid phase reactions of the coal model compound PhOCH/sub 2/Ph (Benzyl phenyl ether, BPE) were detailed for the first time in each of four hydronaphthalene H-donor solvents in the temperature range 220/sup 0/ to 300/sup 0/C. The thermolysis of BPE exhibited a pronounced dependence on solvent structure, both with respect to product selectivities and reaction kinetics. BPE thermolysis pathways were delineated as involving (a) rearrangement, leading to isomerization, (b) hydrogenations, leading ultimately to PhOH and PhCH/sub 3/ products, and (c) addition reactions, engendering heavy products. Pathways (b) and (c) are competitive and, in each, self-reactions of BPE-derivatives vie against reactions between these and the donor solvent. Of the detailed free radical and pericyclic reaction mechanisms postulated, the latter rationalized many more facets of the BPE results than the former. The theoretical and experimental results were appraised against previous coal thermolysis literature.
Thermolysis of phenethyl phenyl ether: a model for ether linkages in lignin and low rank coal
Energy Technology Data Exchange (ETDEWEB)
Britt, P.F.; Buchanan, A.C.; Malcolm, E.A. [Oak Ridge National Laboratory, Oak Ridge, TN (United States). Division of Chemistry and Analytical Science
1995-10-06
The thermolysis of phenethyl phenyl ether (PPE) was studied at 330-425{degree}C to resolve the discrepancies in the reported mechanisms of this important model of the beta-ether linkage found in lignin and low rank coal. Cracking of PPE proceeded by two competitive pathways that produced styrene plus phenol and two previously undetected products, benzaldehyde plus toluene. The ratio of these pathways, defined as the alpha/beta selectivity, was 3.1 +/- 0.3 at 375{degree}C and independent of the PPE concentration. Thermolysis of PPE in tetralin, a model hydrogen donor solvent, increased the alpha/beta selectivity to 7 and accelerated the formation of secondary products. All the data were consistent with a free-radical chain mechanism for the decomposition of PPE. Styrene and phenol are produced by hydrogen abstraction at the alpha-carbon, beta-scission to form styrene and the phenoxy radical, followed by hydrogen abstraction. Benzaldehyde and toluene are formed by hydrogen abstraction at the beta-carbon, 1,2-phenyl migration from oxygen to carbon, beta-scission to form benzaldehyde, and the benzyl radical followed by hydrogen abstraction. Thermochemical kinetic estimates indicate that product formation is controlled by the relative rate of hydrogen abstraction at the alpha- and beta-carbons by the phenoxy radical (dominant) and benzyl radical (minor) since beta-scission and 1,2-phenyl migration are fast relative to hydrogen abstraction. Thermolysis of PhCD{sub 2}CH{sub 2}OPh and PhCH{sub 2}CD{sub 2}OPh was consistent with the previous results, indicating that there was no significant contribution of a concerted retro-ene pathway to the thermolysis of PPE.
Energy Technology Data Exchange (ETDEWEB)
Khvorov, M.M.; Dudchenko, A.K.; Khimchenko, IU.I.
1986-05-01
Histograms of the size distribution of ultradisperse nickel particles produced by the thermolysis of amine complexes are plotted using dark-field and light-field electron microscopy data. It is found that the size distribution can be adequately approximated by logarithmically probabilistic functions. The ultradisperse nickel particles feature several types of structure, i.e., faceted stable single crystals coated by an organic film, small aggregates of such crystals, large stable globules, and hexahedral and trihedral crystals. 8 references.
Feng, Liang
2018-01-18
Sufficient pore size, appropriate stability and hierarchical porosity are three prerequisites for open frameworks designed for drug delivery, enzyme immobilization and catalysis involving large molecules. Herein, we report a powerful and general strate-gy, linker thermolysis, to construct ultra-stable hierarchically porous metal−organic frameworks (HP-MOFs) with tunable pore size distribution. Linker instability, usually an undesirable trait of MOFs, was exploited to create mesopores by generating crystal defects throughout a microporous MOF crystal via thermolysis. The crystallinity and stability of HP-MOFs remain after thermolabile linkers are selectively removed from multivariate metal-organic frameworks (MTV-MOFs) through a decarboxyla-tion process. A domain-based linker spatial distribution was found to be critical for creating hierarchical pores inside MTV-MOFs. Furthermore, linker thermolysis promotes the formation of ultra-small metal oxide (MO) nanoparticles immobilized in an open framework that exhibits high catalytic activity for Lewis acid catalyzed reactions. Most importantly, this work pro-vides fresh insights into the connection between linker apportionment and vacancy distribution, which may shed light on prob-ing the disordered linker apportionment in multivariate systems, a long-standing challenge in the study of MTV-MOFs.
RETRACTED ARTICLE: The Effect of Solute Atoms on Grain Boundary Migration: A Solute Pinning Approach
Hersent, Emmanuel; Marthinsen, Knut; Nes, Erik
2012-12-01
The effect of solute atoms on grain boundary migration has been modeled on the basis of the idea that solute atoms will locally perturb the collective rearrangements of solvent atoms associated with boundary migration. The consequence of such perturbations is the cusping of the boundary and corresponding stress concentrations on the solute atoms which will promote thermal activation of these atoms out of the boundary. This thermal activation is considered to be the rate-controlling mechanism in boundary migration. It is demonstrated that the present statistical approach is capable of explaining, in phenomenological terms, the known effects of solute atoms on boundary migration. The experimental results on the effect of copper on boundary migration in aluminum, due to Gordon and Vandermeer, have been well accounted for.
Calcium ferrite formation from the thermolysis of calcium tris (maleato)
Indian Academy of Sciences (India)
stoichiometric quantities of aqueous solutions of calcium maleate, iron(III) maleate and maleic acid. The reaction mixture was concentrated on a water bath until a brown coloured product formed after the addition of excess of acetone. The complex was vacuum dried and its identity was established by chemical analysis.
Prajapati, Abhinesh Kumar; Chaudhari, Parmesh Kumar; Mazumdar, Bidyut; Choudhary, Rumi
2015-01-01
The catalytic thermolysis (CT) process is an effective and novel approach to treat rice grain-based biodigester effluent (BDE) of the distillery plant. CT treatment of rice grain-based distillery wastewater was carried out in a 0.5 dm(3) thermolytic batch reactor using different catalysts such as CuO, copper sulphate and ferrous sulphate. With the CuO catalyst, a temperature of 95°C, catalyst loading of 4 g/dm(3) and pH 5 were found to be optimal, obtaining a maximum chemical oxygen demand (COD) and colour removal of 80.4% and 72%, respectively. The initial pH (pHi) was an important parameter to remove COD and colour from BDE. At higher pHi (pH 9.5), less COD and colour reduction were observed. The settling characteristics of CT-treated sludge were also analysed at different temperatures. It was noted that the treated slurry at a temperature of 80°C gave best settling characteristics. Characteristics of residues are also analysed at different pH.
Aulenbach, Brent T.; Burns, Douglas A.; Shanley, James B.; Yanai, Ruth D.; Bae, Kikang; Wild, Adam; Yang, Yang; Yi, Dong
2016-01-01
Estimating streamwater solute loads is a central objective of many water-quality monitoring and research studies, as loads are used to compare with atmospheric inputs, to infer biogeochemical processes, and to assess whether water quality is improving or degrading. In this study, we evaluate loads and associated errors to determine the best load estimation technique among three methods (a period-weighted approach, the regression-model method, and the composite method) based on a solute's concentration dynamics and sampling frequency. We evaluated a broad range of varying concentration dynamics with stream flow and season using four dissolved solutes (sulfate, silica, nitrate, and dissolved organic carbon) at five diverse small watersheds (Sleepers River Research Watershed, VT; Hubbard Brook Experimental Forest, NH; Biscuit Brook Watershed, NY; Panola Mountain Research Watershed, GA; and Río Mameyes Watershed, PR) with fairly high-frequency sampling during a 10- to 11-yr period. Data sets with three different sampling frequencies were derived from the full data set at each site (weekly plus storm/snowmelt events, weekly, and monthly) and errors in loads were assessed for the study period, annually, and monthly. For solutes that had a moderate to strong concentration–discharge relation, the composite method performed best, unless the autocorrelation of the model residuals was solutes that had a nonexistent or weak concentration–discharge relation (modelR2 solutes with the strongest concentration–discharge relations. Sample and regression model diagnostics could be used to approximate overall accuracies and annual precisions. For the period-weighed approach, errors were lower when the variance in concentrations was lower, the degree of autocorrelation in the concentrations was higher, and sampling frequency was higher. The period-weighted approach was most sensitive to sampling frequency. For the regression-model and composite methods, errors were lower when
Thermolysis of scrap tire and rubber in sub/super-critical water.
Li, Qinghai; Li, Fuxin; Meng, Aihong; Tan, Zhongchao; Zhang, Yanguo
2017-10-25
The rapid growth of waste tires has become a serious environmental issue. Energy and material recovery is regarded as a promising use for waste tires. Thermolysis of scrap tire (ST), natural rubber (NR), and styrene-butadiene rubber (SBR) was carried out in subcritical and supercritical water using a temperature-pressure independent adjustable batch tubular reactor. As a result, oil yields increased as temperature and pressure increased, and they reached maximum values as the state of water was near the critical point. However, further increases in water temperature and pressure reduced the oil yields. The maximum oil yield of 21.21% was obtained at 420 °C and 18 MPa with a reaction time of 40 min. The relative molecular weights of the chemicals in the oil products were in the range of 70-140 g/mole. The oil produced from ST, NR, and SBR contained similar chemical compounds, but the oil yield of SR was between those of NR and SBR. The oil yield from thermolysis of subcritical or supercritical water should be further improved. The main gaseous products, including CH4, C2H2, C2H4, C2H6, and C3H8, increased with reaction time, temperature, and pressure, whereas the solid residues, including carbon black and impurities, decreased. These results provide useful information to develop a sub/super-critical water thermolysis process for energy and material regeneration from waste tires. Copyright © 2017 Elsevier Ltd. All rights reserved.
Lau, Yen-Yie; Wong, Yee-Shian; Ang, Tze-Zhang; Ong, Soon-An; Lutpi, Nabilah Aminah; Ho, Li-Ngee
2017-12-23
The theme of present research demonstrates performance of copper (II) sulfate (CuSO 4 ) as catalyst in thermolysis process to treat reactive black 5 (RB 5) dye. During thermolysis without presence of catalyst, heat was converted to thermal energy to break the enthalpy of chemical structure bonding and only 31.62% of color removal. With CuSO 4 support as auxiliary agent, the thermally cleaved molecular structure was further destabilized and reacted with CuSO 4 . Copper ions functioned to delocalize the coordination of π of the lone paired electron in azo bond, C=C bond of the sp 2 carbon to form C-C of the sp 3 amorphous carbon in benzene and naphthalene. Further, the radicals of unpaired electrons were stabilized and RB 5 was thermally decomposed to methyl group. Zeta potential measurement was carried out to analyze the mechanism of RB 5 degradation and measurement at 0 mV verified the critical chemical concentration (CCC) (0.7 g/L copper (II) sulfate), as the maximum 92.30% color removal. The presence of copper (II) sulfate catalyst has remarkably increase the RB 5 dye degradation as the degradation rate constant without catalyst, k 1 is 6.5224 whereas the degradation rate constant with catalyst, k 2 is 25.6810. This revealed the correlation of conversion of thermal energy from heat to break the chemical bond strength, subsequent fragmentation of RB 5 dye molecular mediated by copper (II) sulfate catalyst. The novel framework on thermolysis degradation of molecular structure of RB 5 with respect to the bond enthalpy and interfacial intermediates decomposition with catalyst reaction were determined.
Neutral solute transport across osteochondral interface: A finite element approach.
Arbabi, Vahid; Pouran, Behdad; Weinans, Harrie; Zadpoor, Amir A
2016-12-08
Investigation of the solute transfer across articular cartilage and subchondral bone plate could nurture the understanding of the mechanisms of osteoarthritis (OA) progression. In the current study, we approached the transport of neutral solutes in human (slight OA) and equine (healthy) samples using both computed tomography and biphasic-solute finite element modeling. We developed a multi-zone biphasic-solute finite element model (FEM) accounting for the inhomogeneity of articular cartilage (superficial, middle and deep zones) and subchondral bone plate. Fitting the FEM model to the concentration-time curves of the cartilage and the equilibrium concentration of the subchondral plate/calcified cartilage enabled determination of the diffusion coefficients in the superficial, middle and deep zones of cartilage and subchondral plate. We found slightly higher diffusion coefficients for all zones in the human samples as compared to the equine samples. Generally the diffusion coefficient in the superficial zone of human samples was about 3-fold higher than the middle zone, the diffusion coefficient of the middle zone was 1.5-fold higher than that of the deep zone, and the diffusion coefficient of the deep zone was 1.5-fold higher than that of the subchondral plate/calcified cartilage. Those ratios for equine samples were 9, 2 and 1.5, respectively. Regardless of the species considered, there is a gradual decrease of the diffusion coefficient as one approaches the subchondral plate, whereas the rate of decrease is dependent on the type of species. Copyright © 2016 Elsevier Ltd. All rights reserved.
Spontaneous formation and characterization of silicon carbide nanowires produced via thermolysis
Energy Technology Data Exchange (ETDEWEB)
Soszynski, Michal; Dabrowska, Agnieszka; Huczko, Andrzej [Laboratory of Nanomaterials Physics and Chemistry, Department of Chemistry, Warsaw University, 1 Pasteur str., 02-093 Warsaw (Poland)
2011-11-15
We report on experiments to optimize the process of preparation of silicon carbide nanowires (SiCNWs) by a combustion synthesis (thermolysis). The morphology of starting reactants and combustion atmosphere were varied and we observed the effect of those variables on product yield and characteristics. The produced SiCNWs were characterized using SEM, TEM, XRD, and wet chemistry analysis. High-pressure reactor used for combustion synthesis, combustion reaction, and TEM of produced SiCNW. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Multiscale Multilevel Approach to Solution of Nanotechnology Problems
Polyakov, Sergey; Podryga, Viktoriia
2018-02-01
The paper is devoted to a multiscale multilevel approach for the solution of nanotechnology problems on supercomputer systems. The approach uses the combination of continuum mechanics models and the Newton dynamics for individual particles. This combination includes three scale levels: macroscopic, mesoscopic and microscopic. For gas-metal technical systems the following models are used. The quasihydrodynamic system of equations is used as a mathematical model at the macrolevel for gas and solid states. The system of Newton equations is used as a mathematical model at the mesoand microlevels; it is written for nanoparticles of the medium and larger particles moving in the medium. The numerical implementation of the approach is based on the method of splitting into physical processes. The quasihydrodynamic equations are solved by the finite volume method on grids of different types. The Newton equations of motion are solved by Verlet integration in each cell of the grid independently or in groups of connected cells. In the framework of the general methodology, four classes of algorithms and methods of their parallelization are provided. The parallelization uses the principles of geometric parallelism and the efficient partitioning of the computational domain. A special dynamic algorithm is used for load balancing the solvers. The testing of the developed approach was made by the example of the nitrogen outflow from a balloon with high pressure to a vacuum chamber through a micronozzle and a microchannel. The obtained results confirm the high efficiency of the developed methodology.
Fast solutions for UC problems by a new metaheuristic approach
Energy Technology Data Exchange (ETDEWEB)
Viana, Ana; de Sousa, J. Pinho; Matos, Manuel A. [INESC Porto, Campus da FEUP, Rua Dr. Roberto Frias 378, 4200-465 Porto (Portugal)
2008-08-15
Due to its combinatorial nature, the Unit Commitment problem has for long been an important research challenge, with several optimization techniques, from exact to heuristic methods, having been proposed to deal with it. In line with one current trend of research, metaheuristic approaches have been studied and some interesting results have already been achieved and published. However, a successful utilization of these methodologies in practice, when embedded in Energy Management Systems, is still constrained by the reluctance of industrial partners in using techniques whose performance highly depends on a correct parameter tuning. Therefore, the application of metaheuristics to the Unit Commitment problem does still justify further research. In this paper we propose a new search strategy, for Local Search based metaheuristics, that tries to overcome this issue. The approach has been tested in a set of instances, leading to very good results in terms of solution cost, when compared either to the classical Lagrangian Relaxation or to other metaheuristics. It also drastically reduced the computation times. Furthermore, the approach proved to be robust, always leading to good results independently of the metaheuristic parameters used. (author)
Static and dynamic pressure effects on the thermolysis of nitroalkanes in solution
Energy Technology Data Exchange (ETDEWEB)
Brower, K.R. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States). Dept. of Chemistry; Davis, L.L.; Naud, D.L. [Los Alamos National Lab., NM (United States); Wang, J. [Univ. of Southern California, Los Angeles, CA (United States). Dept. of Chemistry
1998-12-31
The authors have measured the effects of static and shock-induced pressures on the decomposition rates and mechanisms of various nitroalkanes dissolved in different solvents with and without organic amine catalysts. While nitroalkanes without {alpha}-hydrogen decompose by homolysis of the C-NO{sub 2} bond over a wide range of conditions, the decomposition pathway of nitroalkanes having {alpha}-hydrogens (i.e., acidic nitroalkanes) is complicated and follows different decomposition mechanisms depending on the availability of organic base and reaction pressure. The Nef reaction is also an important reaction pathway. The five known decomposition pathways, homolysis of the C-NO{sub 2} bond, bimolecular reaction between the aci-form and aci-ion, cyclization of the aci-form, elimination of nitrous acid, and the Nef reaction, are highly dependent on the reaction conditions, such as pressure, presence of organic amines, water, alcohols, and polarity of solvent. The authors discuss the results of several tests used to support these various decomposition mechanisms.
Designing e-learning solutions with a client centred approach
DEFF Research Database (Denmark)
Ørngreen, Rikke; Nielsen, Janni; Levinsen, Karin
2008-01-01
This paper claims that the strategies applied in designing e-learning solutions tend to focus on how to proceed after the precondition, e.g., learners requirements, pedagogical choice, etc., have been decided upon. Investigating the HCI research field, we find that the methodological approaches...... as the organisation that has initiated the e-learning project and needs to manage the e-learning system after its development. Through the Client Centred Design and in close collaboration with the client, three strategic issues are uncovered and strategic models are presented for each. These models are complementary...... perspectives in a Client Centred framework that is useable as the starting point for others in developing large scale e-learning projects....
Directory of Open Access Journals (Sweden)
Luís Pinto da Silva
2017-01-01
Full Text Available Chemi-/bioluminescence are phenomena in which chemical energy is converted into electronically excited singlet states, which decay with light emission. Given this feature, along with high quantum yields and other beneficial characteristics, these systems have gained numerous applications in bioanalysis, in biomedicine, and in the pharmaceutical field. Singlet chemiexcitation is made possible by the formation of cyclic peroxides (as dioxetanones as thermolysis provides a route for a ground state reaction to produce singlet excited states. However, such thermolysis can also lead to the formation of triplet states. While triplet states are not desired in the typical applications of chemi-/bioluminescence, the efficient production of such states can open the door for the use of these systems as sensitizers in photocatalysis and triplet-triplet annihilation, among other fields. Thus, the goal of this study is to assess the effect of heavy atom addition on the thermolysis and triplet chemiexcitation of a model dioxetanone. Monobromination does not affect the thermolysis reaction but can improve the efficiency of intersystem crossing, depending on the position of monobromination. Addition of bromine atoms to the triplet state reaction product has little effect on its properties, except on its electron affinity, in which monobromination can increase between 3.1 and 8.8 kcal mol−1.
Modern Urban Naming Practices: Strategic Approaches and Practical Solutions
Directory of Open Access Journals (Sweden)
Marina V. Golomidova
2017-11-01
Full Text Available The article looks at the problems of the naming of municipal facilities. The author analyzes the existing policy in assigning new names and renaming urban sites, describes the current strategic approaches to urban naming and proposes a new strategy based on congruity with the holistic image of the city. The current approaches to urban naming mark the predominating interest in the historical and cultural heritage of cities as a valuable source for the toponymic nomination shared both by native and foreign experts. However, this commitment to the past may run counter to the modern arrangement and perception of the urban space, as well as impede the city development prospects. From the standpoint of modern area marketing, names of urban sites are regarded as an information and communication resource highly relevant to the city image formation and promotion. In the author’s view, the benefits of adopting a new strategy may also resonate with the concept of “urbanonymic construction,” which is understood as sustainable and streamlined management policy aimed at the progressive implementation of long-term programs for individual urban site names consistency. The urbanonymic construction involves a normative, regulatory aspect; formation of the holistic city image that builds on its resource base, the symbolic capital, and the development strategy; definition of key characteristics of the city image which are most relevant to its positioning; identification of principal nominative themes for verbal representation of the city image; use of naming technologies to ensure the relevance of the name’s implications; testing and expert evaluation of new names. Drawing on domestic and foreign expertise in the same study field, a number of practical solutions for the creation of new urbanonyms are described.
Gas-phase thermolysis reaction of formaldehyde diperoxide. Kinetic study and theoretical mechanisms
Energy Technology Data Exchange (ETDEWEB)
Jorge, Nelly Lidia [Instituto Andaluz de Ciencias de la Tierra, CSIC-Universidad de Granada, Av. Las Palmeras 4, 18100 Armilla, Granada (Spain); Area de Quimica Fisica Facultad de Ciencias Exactas y Naturales y Agrimensura, UNNE, Avda. Libertad 5460, 3400 Corrientes (Argentina); Romero, Jorge Marcelo [Area de Quimica Fisica Facultad de Ciencias Exactas y Naturales y Agrimensura, UNNE, Avda. Libertad 5460, 3400 Corrientes (Argentina); Grand, Andre [INAC, SCIB, Laboratoire ' Lesions des Acides Nucleiques' , UMR CEA-UJF E3, CEA-Grenoble, 17 Rue des Martyrs, 38054 Grenoble cedex 9 (France); Hernandez-Laguna, Alfonso, E-mail: ahlaguna@ugr.es [Instituto Andaluz de Ciencias de la Tierra, CSIC-Universidad de Granada, Av. Las Palmeras 4, 18100 Armilla, Granada (Spain)
2012-01-17
Highlights: Black-Right-Pointing-Pointer Kinetic and mechanism of the gas-phase thermolysis of tetroxane were determined. Black-Right-Pointing-Pointer Gas chromatography and computational potential energy surfaces were performed. Black-Right-Pointing-Pointer A mechanism in steps looked like the most probable mechanism. Black-Right-Pointing-Pointer A spin-orbit coupling appeared at the singlet and triple diradical open structures. Black-Right-Pointing-Pointer A non-adiabatic crossing from the singlet to the triplet state occurred. - Abstract: Gas-phase thermolysis reaction of formaldehyde diperoxide (1,2,4,5-tetroxane) was performed in an injection chamber of a gas chromatograph at a range of 463-503 K. The average Arrhenius activation energy and pre-exponential factor were 29.3 {+-} 0.8 kcal/mol and 5.2 Multiplication-Sign 10{sup 13} s{sup -1}, respectively. Critical points and reaction paths of the ground singlet and first triplet potential energy surfaces (PES) were calculated, using DFT method at BHANDHLYP/6-311+G{sup Asterisk-Operator Asterisk-Operator} level of the theory. Also, G3 calculations were performed on the reactant and products. Reaction by the ground-singlet and first-triplet states turned out to be endothermic and exothermic, respectively. The mechanism in three steps seemed to be the most probable one. An electronically non-adiabatic process appeared, in which a crossing, at an open diradical structure, from the singlet to the triplet state PES occurred, due to a spin-orbit coupling, yielding an exothermic reaction. Theoretical kinetic constant coming from the non- adiabatic transition from the singlet to the triplet state agrees with the experimental values.
Designing Digital Preservation Solutions: A Risk Management-Based Approach
Directory of Open Access Journals (Sweden)
José Barateiro
2010-07-01
Full Text Available Digital preservation aims to keep digital objects accessible over long periods of time, ensuring the authenticity and integrity of these digital objects. In such complex environments, Risk Management is a key factor in assuring the normal behaviour of systems over time. Currently, the digital preservation arena commonly uses Risk Management concepts to assess repositories. In this paper, we intend to go further and propose a perspective where Risk Management can be used not only to assess existing solutions, but also to conceive digital preservation environments. Thus, we propose a Risk Management-based approach to design and assess digital preservation environments, including:• the definition of context and identification of strategic objectives to determine specific requirements and characterize which consequences are acceptable within the identified context;• the identification, analysis and evaluation of threats and vulnerabilities that may affect the normal behaviour of a specific business or the achievement of the goals and conformance to the requirements identified in the context characterization; and, • definition of actions to deal with the risks associated with the identified threats and vulnerabilities.We generalize and survey the main requirements, threats, vulnerabilities and techniques that can be applied in the scope of digital preservation.
Low temperature preparation of nanocrystalline solid solution of ...
Indian Academy of Sciences (India)
Unknown
ASIT B PANDA, AMITA PATHAK and PANCHANAN PRAMANIK*. Department of Chemistry, Indian Institute of Technology, Kharagpur 721 302, India. Abstract. SrxBa1–xNb2O6 (with x = 0⋅4, 0⋅5 and 0⋅6) powders have been prepared by thermolysis of aqueous precursor solutions consisting of triethanolamine (TEA), ...
Energy Technology Data Exchange (ETDEWEB)
Burkova, V.N.; Glebovskaya, Ye.A.; Reztsov, V.I.; Serebrennikova, O.V.; Titov, V.I.
1984-01-01
The change in the composition of vanadylporphyrin during thermolysis is examined. It is shown that the presence of a mineral part catalyzes the process of breakdown of the porphyrin which contain an isocyclic ring, as well as high molecular mass porphyrines. High pressures has no effect on the breakdown of porphyrines of the M-2 series with thermolysis, but slows the breakdown of high molecular porphyrines.
An adaptive approach to implementing innovative urban transport solutions
Marchau, V.; Walker, W.; Van Duin, R.
2009-01-01
Urban transport is facing an increasing number of problems. Innovative technological solutions have been proposed for many of these problems. The implementation of these solutions, however, is surrounded by many uncertainties—for example, future relevant developments for urban transport demand and
Online Learning Integrity Approaches: Current Practices and Future Solutions
Lee-Post, Anita; Hapke, Holly
2017-01-01
The primary objective of this paper is to help institutions respond to the stipulation of the Higher Education Opportunity Act of 2008 by adopting cost-effective academic integrity solutions without compromising the convenience and flexibility of online learning. Current user authentication solutions such as user ID and password, security…
Solute transport with multiprocess nonequilibrium: a semi-analytical solution approach
Neville, Christopher J.; Ibaraki, Motomu; Sudicky, Edward A.
2000-07-01
A semi-analytical solution for the simulation of one-dimensional subsurface solute transport incorporating multiple nonequilibrium processes is presented. The solution is based on the theory developed by Brusseau et al. (1992) [Brusseau, M.L., Jessup, R.E., Rao, P.S.C., 1992. Modeling solute transport influenced by multiprocess nonequilibrium and transformation reactions. Water Resources Research 28 (1), 175-182.] which is a generalized combination of two-site and two-region model. In addition to developing a semi-analytical complement to their numerical solution, we extend the range of boundary and initial conditions considered. The semi-analytical solution can represent domains of both finite and semi-infinite extent and accommodates nonzero initial concentrations. The solution is derived in Laplace space and final results are obtained using an accurate and robust numerical inversion algorithm. The solution is particularly well suited for interpreting experimental results obtained under controlled laboratory conditions. Identification of the input parameters for the solution is examined by simulating a column experiment by van Genuchten (1974) [van Genuchten, M., 1974. Mass Transfer Studies in Sorbing Porous Media. PhD thesis, New Mexico State University, Las Cruces, NM.].
Rational Solutions to the ABS List: Transformation Approach
Zhang, Danda; Zhang, Da-Jun
2017-10-01
In the paper we derive rational solutions for the lattice potential modified Korteweg-de Vries equation, and Q2, Q1(δ), H3(δ), H2 and H1 in the Adler-Bobenko-Suris list. Bäcklund transformations between these lattice equations are used. All these rational solutions are related to a unified τ function in Casoratian form which obeys a bilinear superposition formula.
Feng, Mingbao; Qu, Ruijuan; Wei, Zhongbo; Wang, Liansheng; Sun, Ping; Wang, Zunyao
2015-05-01
The thermal decomposition of Nafion N117 membrane, a typical perfluorosulfonic acid membrane that is widely used in various chemical technologies, was investigated in this study. Structural identification of thermolysis products in water and methanol was performed using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS). The fluoride release was studied using an ion-chromatography system, and the membrane thermal stability was characterized by thermogravimetric analysis. Notably, several types of perfluorinated compounds (PFCs) including perfluorocarboxylic acids were detected and identified. Based on these data, a thermolysis mechanism was proposed involving cleavage of both the polymer backbone and its side chains by attack of radical species. This is the first systematic report on the thermolysis products of Nafion by simulating its high-temperature operation and disposal process via incineration. The results of this study indicate that Nafion is a potential environmental source of PFCs, which have attracted growing interest and concern in recent years. Additionally, this study provides an analytical justification of the LC/ESI-MS/MS method for characterizing the degradation products of polymer electrolyte membranes. These identifications can substantially facilitate an understanding of their decomposition mechanisms and offer insight into the proper utilization and effective management on these membranes.
Surface integrals approach to solution of some free boundary problems
Directory of Open Access Journals (Sweden)
Igor Malyshev
1988-01-01
Full Text Available Inverse problems in which it is required to determine the coefficients of an equation belong to the important class of ill-posed problems. Among these, of increasing significance, are problems with free boundaries. They can be found in a wide range of disciplines including medicine, materials engineering, control theory, etc. We apply the integral equations techniques, typical for parabolic inverse problems, to the solution of a generalized Stefan problem. The regularization of the corresponding system of nonlinear integral Volterra equations, as well as local existence, uniqueness, continuation of its solution, and several numerical experiments are discussed.
Visual C# 2010 Recipes A Problem-Solution Approach
Jones, Allen; MacDonald, Matthew; Rajan, Rakesh
2010-01-01
Mastering the development of .NET 4.0 applications in C# is less about knowing the Visual C# 2010 language and more about knowing how to use the functionality of the .NET Framework class library most effectively. Visual C# 2010 Recipes explores the breadth of the .NET Framework class library and provides specific solutions to common and interesting programming problems. Each recipe is presented in a succinct problem/solution format and is accompanied by a working code sample to help you understand the concept and quickly apply it. When you are facing a Visual C# 2010 problem, this book likely
Solidified reverse micellar solutions (SRMS): A novel approach for ...
African Journals Online (AJOL)
AMARA
lipids based drug delivery systems. Salome Amarachi Chime* and Ikechukwu V. Onyishi. Department of Pharmaceutical Technology and Industrial Pharmacy, University of Nigeria, Nsukka 410001, Nigeria. Accepted 24 December, 2013. Solidified reverse micellar solutions (SRMS) are reverse micelles containing lecithin ...
Solidified reverse micellar solutions (SRMS): A novel approach for ...
African Journals Online (AJOL)
Solidified reverse micellar solutions (SRMS) are reverse micelles containing lecithin and a triglyceride, for example, SOFTISAN®142, which is hydrogenated coco glyceride. SRMS transform into a lamellar mesophase after melting on contact with water; this transformation enables controlled release of solubilized drugs.
Thermolysis of phenethyl phenyl ether: A model of ether linkages in low rank coal
Energy Technology Data Exchange (ETDEWEB)
Britt, P.F.; Buchanan, A.C. III; Malcolm, E.A.
1994-09-01
Currently, an area of interest and frustration for coal chemists has been the direct liquefaction of low rank coal. Although low rank coals are more reactive than bituminous coals, they are more difficult to liquefy and offer lower liquefaction yields under conditions optimized for bituminous coals. Solomon, Serio, and co-workers have shown that: in the pyrolysis and liquefaction of low rank coals, a low temperature cross-linking reaction associated with oxygen functional groups occurs before tar evolution. A variety of pretreatments (demineralization, alkylation, and ion-exchange) have been shown to reduce these retrogressive reactions and increase tar yields, but the actual chemical reactions responsible for these processes have not been defined. In order to gain insight into the thermochemical reactions leading to cross-linking in low rank coal, we have undertaken a study of the pyrolysis of oxygen containing coal model compounds. Solid state NMR studies suggest that the alkyl aryl ether linkage may be present in modest amounts in low rank coal. Therefore, in this paper, we will investigate the thermolysis of phenethyl phenyl ether (PPE) as a model of 0-aryl ether linkages found in low rank coal, lignites, and lignin, an evolutionary precursor of coal. Our results have uncovered a new reaction channel that can account for 25% of the products formed. The impact of reaction conditions, including restricted mass transport, on this new reaction pathway and the role of oxygen functional groups in cross-linking reactions will be investigated.
Synthesis of copper and zinc sulfide nanocrystals via thermolysis of the polymetallic thiolate cage
Directory of Open Access Journals (Sweden)
Toshihiro Kuzuya, Yutaka Tai, Saeki Yamamuro and Kenji Sumiyama
2005-01-01
Full Text Available In this paper report on the synthesis of copper and zinc sulfide nanocrystals (NCs via the formation of polymetallic thiolate cages. Cu2S NCs derived from Cu–dodecanethiol complex formed well-defined spherers, which were sufficiently monodisperse (with a size distribution of ~10% standard deviation of approximately 4.7 nm diameter on average to generate ordered self-assemblies. An electron diffraction pattern and UV–vis spectrum of Cu2S NCs indicate that this process can provide pure β-chalcocite (Cu2S. Nearly monodisperse ZnS NCs with a size ranging from 3 to 7 nm were obtained by thermolysis of the S–Zn–dodecanethiol precursor. The electron diffraction pattern indicates that zinc sulfide NCs are either wurtzite or a mixture of wurtzite and zincblende. TEM observation and UV–vis spectra revealed that the growth rate of ZnS NCs depends strongly on the annealing temperature. UV–vis spectra of 3 nm ZnS NCs show sharp excitonic features and a large blue shift from the bulk material. The photoluminescence spectra exhibit a large red shift from the absorption band edges. These shifts could be attributed to recombination from the surface traps. The narrow size distribution of Cu2S and ZnS NCs led to the formation of ordered self-assemblies with various well-defined but nonclosed-packing.
Leardini, Fabrice; Flores, Eduardo; Galvis E, Andrés R.; Ferrer, Isabel J.; Ramón Ares, José; Sánchez, Carlos; Molina, Pablo; van der Meulen, Herko P.; Gómez Navarro, Cristina; López Polin, Guillermo; Urbanos, Fernando J.; Granados, Daniel; García-García, F. Javier; Demirci, Umit B.; Yot, Pascal G.; Mastrangelo, Filippo; Grazia Betti, Maria; Mariani, Carlo
2018-01-01
This work investigates the growth of B–C–N layers by chemical vapor deposition using methylamine borane (MeAB) as the single-source precursor. MeAB has been synthesized and characterized, paying particular attention to the analysis of its thermolysis products, which are the gaseous precursors for B–C–N growth. Samples have been grown on Cu foils and transferred onto different substrates for their morphological, structural, chemical, electronic and optical characterizations. The results of these characterizations indicate a segregation of h-BN and graphene-like (Gr) domains. However, there is an important presence of B and N interactions with C at the Gr borders, and of C interacting at the h-BN-edges, respectively, in the obtained nano-layers. In particular, there is a significant presence of C–N bonds, at Gr/h-BN borders and in the form of N doping of Gr domains. The overall B:C:N contents in the layers is close to 1:3:1.5. A careful analysis of the optical bandgap determination of the obtained B–C–N layers is presented, discussed and compared with previous seminal works with samples of similar composition.
Sharma, Deepak; Prajapati, Abhinesh Kumar; Choudhary, Rumi; Kaushal, Rajesh Kumar; Pal, Dharm; Sawarkar, Ashish N
2017-08-16
CuO catalyst was prepared from copper sulfate by alkali precipitation method followed by drying and calcination. Characterization of CuO catalyst using X-ray diffraction, Brunauer-Emmett-Teller, and Barrett-Joyner-Halenda surface area analysis envisaged the effectiveness of CuO as a catalyst for the treatment of biodigester effluent (BDE) emanated from distilleries. The catalytic thermolysis is an efficient advance treatment method for distillery biodigester effluent (BDE). CT treatment of BDE was carried out in a 0.5 dm 3 thermolytic batch reactor using CuO as a catalyst at different pH (1-9), temperatures (80-110°C), and catalyst loadings (1-4 kg/m 3 ). With CuO catalyst, a temperature of 110°C, catalyst loading of 4 kg/m 3 , and pH of 2 was found to be optimal, providing a maximum reduction in chemical oxygen demand of 65%. The settling characteristics at different temperatures of CT-treated sludge were also presented.
Soliton solutions for ABS lattice equations: I. Cauchy matrix approach
Nijhoff, Frank; Atkinson, James; Hietarinta, Jarmo
2009-10-01
In recent years there have been new insights into the integrability of quadrilateral lattice equations, i.e. partial difference equations which are the natural discrete analogues of integrable partial differential equations in 1+1 dimensions. In the scalar (i.e. single-field) case, there now exist classification results by Adler, Bobenko and Suris (ABS) leading to some new examples in addition to the lattice equations 'of KdV type' that were known since the late 1970s and early 1980s. In this paper, we review the construction of soliton solutions for the KdV-type lattice equations and use those results to construct N-soliton solutions for all lattice equations in the ABS list except for the elliptic case of Q4, which is left to a separate treatment.
Novel Approaches To Numerical Solutions Of Quantum Field Theories
Petrov, D
2005-01-01
Two new approaches to numerically solving Quantum Field Theories are presented. The Source Galerkin technique is a direct approach to determining the generating functional of a theory by solving the Schwinger-Dyson equations. The properties of the Source Galerkin technique are tested by using it to determine the phase structure of the Ultralocal &phis;4 theory. A framework for applying this approach to solving O( N) Nonlinear Sigma model is constructed. The Sinc Function approximation is a highly efficient method of numerically evaluating Feynman diagrams. In the present dissertation the Sinc Function approximation is applied to fermionic fields. The Sinc expanded versions of fermion and photon propagators are derived. The accuracy of this approximation is tested by a direct comparison of the Sinc expanded propagators with exact propagators and by performing several sample calculations of one loop QED diagrams. An analysis of computational properties of the Sinc Function approach is presented.
Ruhul A. Bepari; Bharali, Palash; Birinchi K. Das
2017-01-01
Fe2O3 nanoparticles with diameters in the 7–18 nm range have been synthesized via thermolysis of polyvinyl alcohol (PVA) gels prepared under alkaline pH by adding Fe3+ ions into warm aqueous solutions of PVA. While calcinations at 400 °C, 500 °C and 600 °C give γ-Fe2O3 as the pure product, α-Fe2O3 is obtained by heating the gel at 700 °C. It is found that the calcination temperature has a pronounced effect on the nature of the oxide produced but has little effect on particle size. The resulta...
Directory of Open Access Journals (Sweden)
Ruhul A. Bepari
2017-01-01
Full Text Available Fe2O3 nanoparticles with diameters in the 7–18 nm range have been synthesized via thermolysis of polyvinyl alcohol (PVA gels prepared under alkaline pH by adding Fe3+ ions into warm aqueous solutions of PVA. While calcinations at 400 °C, 500 °C and 600 °C give γ-Fe2O3 as the pure product, α-Fe2O3 is obtained by heating the gel at 700 °C. It is found that the calcination temperature has a pronounced effect on the nature of the oxide produced but has little effect on particle size. The resultant Fe2O3 nanomaterials are ferromagnetic with moderate coercivities. Preliminary investigations suggest that hematite (α-Fe2O3 nanoparticles effectively catalyze the epoxidation of styrene with tert-butyl hydroperoxide (TBHP as the terminal oxidant.
Crossing Rivers Problem Solution with Breadth-First Search Approach
Ratnadewi, R.; Sartika, E. M.; Rahim, R.; Anwar, B.; Syahril, M.; Winata, H.
2018-01-01
Crossing river problem is one of the problems state and space that represents a state by using a rule to define the problem, to find solutions to state and space problem can use breadth first search method by conducting a search based on rule and condition given, it is expected with this research crossing river problem could be solved properly and optimally and also this research can be the basis of solving other similar problems by using breadth first search method, to model the situation and the problem space using Breadth First Search made an application with a programming language.
Parker, A.
1995-07-01
In this second of two articles (designated I and II), the bilinear transformation method is used to obtain stationary periodic solutions of the partially integrable regularized long-wave (RLW) equation. These solutions are expressed in terms of Riemann theta functions, and this approach leads to a new and compact expression for the important dispersion relation. The periodic solution (or cnoidal wave) can be represented as an infinite sum of sech2 ``solitary waves'': this remarkable property may be interpreted in the context of a nonlinear superposition principle. The RLW cnoidal wave approximates to a sinusoidal wave and a solitary wave in the limits of small and large amplitudes, respectively. Analytic approximations and error estimates are given which shed light on the character of the cnoidal wave in the different parameter regimes. Similar results are presented in brief for the related RLW Boussinesq (RLWB) equation.
APPROACH TO CYBER SECURITY ISSUES IN NIGERIA: CHALLENGES AND SOLUTION
Directory of Open Access Journals (Sweden)
Frank Ibikunle
2013-06-01
Full Text Available Cyber-space refers to the boundless space known as the internet. Cyber-security is the body of rules put in place for the protection of the cyber space. Cyber-crime refers to the series of organized crime attacking both cyber space and cyber security. The Internet is one of the fastest-growing areas of technical infrastructure development. Over the past decades, the growth of the internet and its use afforded everyone this opportunity. Google, Wikipedia and Bing to mention a few, give detailed answers to millions of questions every day. Cyberspace is a world that contains just about anything one is searching for. With the advent of these advancements in information accessibility and the advantages and applications of the internet comes an exponentially growing disadvantage- Cyber Crime. Cyber security has risen to become a national concern as threats concerning it now need to be taken more seriously. This paper attempts to provide an overview of Cybercrime and Cyber-security. It defines the concept of cybercrime, identify reasons for cyber-crime and its eradication. It look at those involved and the reasons for their involvement. Methods of stepping up cyber security and the recommendations that would help in checking the increasing rate of cyber-crimes were highlighted. The paper also attempts to name some challenges of cybercrime and present practical and logical solutions to these threats.
Spatial competition facility location models: definition, formulation and solution approach
Energy Technology Data Exchange (ETDEWEB)
Tobin, R.L.; Friesz, T.L.
1984-04-01
Models are presented for locating a firm's production facilities and determining production levels at these facilities so as to maximize the firms profit. These models take into account the changes in prices at each of the spatially separated markets that would result from the increase in supply provided by the new facilities and also from the response of competing firms. Two different models of spatial competition are presented to represent the competitive market situation in which the firm's production facilities are being located. These models are formulated as variational inequalities; recent sensitivity analysis results for variational inequalities are used to develop derivatives of the prices at each of the spatially separated markets with respect to the production levels at each of the spatially separated markets with respect to the production levels at each of the new facilities. These derivatives are used to develop a linear approximation of the implicit function relating prices to productions. A heuristic solution procedure making use of this approximation is proposed.
Energy Technology Data Exchange (ETDEWEB)
Crawford, C. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2017-08-14
Savannah River Remediation (SRR) personnel requested that the Savannah River National Laboratory (SRNL) evaluate available data and determine its applicability to defining the impact of planned glycolate anion additions to Savannah River Site (SRS) High Level Waste (HLW) on Tank Farm flammability (primarily with regard to H_{2} production). Flammability evaluations of formate anion, which is already present in SRS waste, were also needed. This report describes the impacts of glycolate and formate radiolysis and thermolysis on Hydrogen Generation Rate (HGR) calculations for the SRS Tank Farm.
Low temperature preparation of nanocrystalline solid solution of ...
Indian Academy of Sciences (India)
SrBa1–Nb2O6 (with = 0.4, 0.5 and 0.6) powders have been prepared by thermolysis of aqueous precursor solutions consisting of triethanolamine (TEA), niobium tartarate and, EDTA complexes of strontium and barium ions. Complete evaporation of the precursor solution by heating at ∼ 200°C, yields in a fluffy, ...
A new approach for solution of vehicle routing problem with hard ...
Indian Academy of Sciences (India)
... sometimes impossible if number of constraints is large enough (i.e., NP-hard), and solution time of a VRPHTW grows exponentially. As the size of the problem grows, a near optimal solution can be found using a heuristic method. A hierarchical approach consisting of two stages as. ''cluster-first route-second'' is proposed.
A new modeling and solution approach for the number partitioning problem
Directory of Open Access Journals (Sweden)
Bahram Alidaee
2005-01-01
Full Text Available The number partitioning problem has proven to be a challenging problem for both exact and heuristic solution methods. We present a new modeling and solution approach that consists of recasting the problem as an unconstrained quadratic binary program that can be solved by efficient metaheuristic methods. Our approach readily accommodates both the common two-subset partition case as well as the more general case of multiple subsets. Preliminary computational experience is presented illustrating the attractiveness of the method.
Scientific Approach and Inquiry Learning Model in the Topic of Buffer Solution: A Content Analysis
Kusumaningrum, I. A.; Ashadi, A.; Indriyanti, N. Y.
2017-09-01
Many concepts in buffer solution cause student’s misconception. Understanding science concepts should apply the scientific approach. One of learning models which is suitable with this approach is inquiry. Content analysis was used to determine textbook compatibility with scientific approach and inquiry learning model in the concept of buffer solution. By using scientific indicator tools (SIT) and Inquiry indicator tools (IIT), we analyzed three chemistry textbooks grade 11 of senior high school labeled as P, Q, and R. We described how textbook compatibility with scientific approach and inquiry learning model in the concept of buffer solution. The results show that textbook P and Q were very poor and book R was sufficient because the textbook still in procedural level. Chemistry textbooks used at school are needed to be improved in term of scientific approach and inquiry learning model. The result of these analyses might be of interest in order to write future potential textbooks.
Homotopy Analysis Approach to Periodic Solutions of a Nonlinear Jerk Equation
Feng, Shao-Dong; Chen, Li-Qun
2009-12-01
The homotopy analysis method is applied to seek periodic solutions of a nonlinear jerk equation involving the third-order time-derivative. The periodic solutions can be approximated via an analytical series. An auxiliary parameter is introduced to control the convergence region of the solution series. Two numerical examples are presented to demonstrate the effectiveness of the homotopy analysis approach. The examples indicate that, by choosing a proper value of the auxiliary parameter, the first few terms in the solution series yield excellent results.
López, F A; Centeno, T A; Rodríguez, O; Alguacil, E J
2013-05-01
The char produced in the thermolysis of granulated scrap tyres has few market outlets, reducing the economic viability of the thermolytic process. This paper reports the potential of this char as a low-cost precursor of porous carbons. The tyre-derived char was demineralized in either alkaline or acidic media to reduce its ash, zinc, sulfur, and silica contents. The lowest impurity content was achieved with an HNO3/H2O treatment. The resulting demineralized char was then subjected to activation by KOH or CO2. The Brunauer-Emmett-Teller (BET)-specific surface area of the activated carbon produced by the KOH treatment was 242 m2/g, whereas that of the CO2-activated carbon was 720 m2/g. The textural properties of the latter product were similar to those of some commercial activated carbons. The use of tyre-derived char as a precursor of porous carbons could render the thermolytic treatment of scrap tyres more economically attractive. Char produced in thermolysis of granulated scrap tyres has a few market outlets; in this paper an alternative for its use is presented. The char was converted into activated carbon with textural properties similar to those of some commercial activated carbons. This process could render the thermolytic treatment of scrap tyres more economically attractive.
Energy Technology Data Exchange (ETDEWEB)
Buchanan, A.C. III; Britt, P.F.; Thomas, K.B. [Oak Ridge National Laboratory, Oak Ridge, IN (United States). Chemical and Analytical Sciences Division
1998-05-01
Silica nanoparticle surfaces have been chemically modified to contain a molecular probe, 1,2-diphenylethane (bibenzyl), as well as a second spacer molecule of variable structure. Thermolysis kinetics and products at 400{degree}C have been determined for bibenzyl, and the impact of diffusional constraints and spacer molecular structure on the multipathway radical chemistry has been analyzed relative to fluid phases. Unimolecular homolysis rate constants, k = (7-9) x 10{sup -6}s{sup -1}, are found to be independent of spacer molecular structure (naphthalene, diphenylmethane, tetralin) and similar to values measured in fluid phases, indicating the lack of a cage effect on the silica surface. However, the total rate of bibenzyl thermolysis and the resulting product selectivities are profoundly affected by both surface immobilization and the structure of the spacer molecule. Naphthalene spacers behave as `molecular walls` serving as physical barriers to bimolecular hydrogen transfer steps on the surface and augmenting the effects of diffusional constraints. In contrast, diphenylmethane spacers are found to serve as hydrogen transfer, radical relay catalysts that translocate radical sites across the surface and diminish the impact of diffusional constraints. Tetralin spacers undergo significant reaction with free-radical intermediates, selectively producing the isomeric methylindan via a chain pathway that is promoted by the restrictions on diffusion. 29 refs., 4 figs., 5 tabs.
Mittra, R.; Ko, W. L.; Rahmat-Samii, Y.
1979-01-01
This paper presents a brief review of some recent developments on the use of the spectral-domain approach for deriving high-frequency solutions to electromagnetics scattering and radiation problems. The spectral approach is not only useful for interpreting the well-known Keller formulas based on the geometrical theory of diffraction (GTD), it can also be employed for verifying the accuracy of GTD and other asymptotic solutions and systematically improving the results when such improvements are needed. The problem of plane wave diffraction by a finite screen or a strip is presented as an example of the application of the spectral-domain approach.
Theoretical approach to the destruction or sterilization of drugs in aqueous solution
Slegers, Catherine; Tilquin, Bernard
2005-02-01
Two novel applications in the radiation processing of aqueous solutions of drugs are the sterilization of injectable drugs and the decontamination of hospital wastewaters by ionizing radiation. The parameters influencing the destruction of the drug in aqueous solutions are studied with a computer simulation program. This theoretical approach has revealed that the dose rate is the most important parameter that can be easily varied in order to optimize the destruction or the protection of the drug.
Zuehlsdorff, T J; Isborn, C M
2018-01-14
The correct treatment of vibronic effects is vital for the modeling of absorption spectra of many solvated dyes. Vibronic spectra for small dyes in solution can be easily computed within the Franck-Condon approximation using an implicit solvent model. However, implicit solvent models neglect specific solute-solvent interactions on the electronic excited state. On the other hand, a straightforward way to account for solute-solvent interactions and temperature-dependent broadening is by computing vertical excitation energies obtained from an ensemble of solute-solvent conformations. Ensemble approaches usually do not account for vibronic transitions and thus often produce spectral shapes in poor agreement with experiment. We address these shortcomings by combining zero-temperature vibronic fine structure with vertical excitations computed for a room-temperature ensemble of solute-solvent configurations. In this combined approach, all temperature-dependent broadening is treated classically through the sampling of configurations and quantum mechanical vibronic contributions are included as a zero-temperature correction to each vertical transition. In our calculation of the vertical excitations, significant regions of the solvent environment are treated fully quantum mechanically to account for solute-solvent polarization and charge-transfer. For the Franck-Condon calculations, a small amount of frozen explicit solvent is considered in order to capture solvent effects on the vibronic shape function. We test the proposed method by comparing calculated and experimental absorption spectra of Nile red and the green fluorescent protein chromophore in polar and non-polar solvents. For systems with strong solute-solvent interactions, the combined approach yields significant improvements over the ensemble approach. For systems with weak to moderate solute-solvent interactions, both the high-energy vibronic tail and the width of the spectra are in excellent agreement with
Energy Technology Data Exchange (ETDEWEB)
Tajahmad, Behzad [University of Tabriz, Faculty of Physics, Tabriz (Iran, Islamic Republic of)
2017-04-15
In this paper, we present the Noether symmetries of flat FRW spacetime in the context of a new action in teleparallel gravity which we construct based on the f(R) version. This modified action contains a coupling between the scalar field potential and magnetism. Also, we introduce an innovative approach, the beyond Noether symmetry (B.N.S.) approach, for exact solutions which carry more conserved currents than the Noether approach. By data analysis of the exact solutions, obtained from the Noether approach, late-time acceleration and phase crossing are realized, and some deep connections with observational data such as the age of the universe, the present value of the scale factor as well as the state and deceleration parameters are observed. In the B.N.S. approach, we consider the dark energy dominated era. (orig.)
ASP.NET MVC 4 recipes a problem-solution approach
Ciliberti, John
2013-01-01
ASP.NET MVC 4 Recipes is a practical guide for developers creating modern web applications, cutting through the complexities of ASP.NET, jQuery, Knockout.js and HTML 5 to provide straightforward solutions to common web development problems using proven methods based on best practices. The problem-solution approach gets you in, out, and back to work quickly while deepening your understanding of the underlying platform and how to develop with it. Author John Ciliberti guides you through the framework and development tools, presenting typical challenges, along with code solutions and clear, conci
Directory of Open Access Journals (Sweden)
Frank Zimmermann
2006-12-01
Full Text Available The main objective of this article is to describe different solution approaches for e-Government processes across different institutions at different levels of public administrations: a phased approach for specific e-Government solutions and a platform approach for cross-organisational public services. We discuss selection criteria for the different approaches considering several examples and indicate a relationship between the expected return-on-investment and the complexity of the solution.
Loup, Christophe; Tesouro Vallina, Ana; Coppel, Yannick; Létinois, Ulla; Nakabayashi, Yasuo; Meunier, Bernard; Lippert, Bernhard; Pratviel, Geneviève
2010-10-04
Two Pt(IV) and two Pt(II) complexes containing a 2,2'-bipyridine ligand were treated with a short DNA oligonucleotide under light irradiation at 37°C or in the dark at 37 and 50°C. Photolysis and thermolysis of the Pt(IV) complexes led to spontaneous reduction of the Pt(IV) to the corresponding Pt(II) complexes and to binding of Pt(II) 2,2'-bipyridine complexes to N7 of guanine. When the reduction product was [Pt(bpy)Cl(2)], formation of bis-oligonucleotide adducts was observed, whereas [Pt(bpy)(MeNH(2))Cl](+) gave monoadducts, with chloride ligands substituted in both cases. Neither in the dark nor under light irradiation was the reductive elimination process of these Pt(IV) complexes accompanied by oxidative DNA damage. This work raises the question of the stability of photoactivatable Pt(IV) complexes toward moderate heating conditions.
SOA enabled ELTA: approach in designing business intelligence solutions in Era of Big Data
Directory of Open Access Journals (Sweden)
Viktor Dmitriyev
2015-01-01
Full Text Available The current work presents a new approach for designing business intelligence solutions. In the Era of Big Data, former and robust analytical concepts and utilities need to adapt themselves to the changed market circumstances. The main focus of this work is to address the acceleration of building process of a “data-centric” Business Intelligence (BI solution besides preparing BI solutions for Big Data utilization. This research addresses the following goals: reducing the time spent during business intelligence solution’s design phase; achieving flexibility of BI solution by adding new data sources; and preparing BI solution for utilizing Big Data concepts. This research proposes an extension of the existing Extract, Load and Transform (ELT approach to the new one Extract, Load, Transform and Analyze (ELTA supported by service-orientation concept. Additionally, the proposed model incorporates Service-Oriented Architecture concept as a mediator for the transformation phase. On one side, such incorporation brings flexibility to the BI solution and on the other side; it reduces the complexity of the whole system by moving some responsibilities to external authorities.
Advanced material and approach for metal ions removal from aqueous solutions
Turhanen, Petri A.; Vepsäläinen, Jouko J.; Peräniemi, Sirpa
2015-03-01
A Novel approach to remove metals from aqueous solutions has been developed. The method is based on a resin free, solid, non-toxic, microcrystalline bisphosphonate material, which has very low solubility in water (59 mg/l to ion free Milli-Q water and 13 mg/l to 3.5% NaCl solution). The material has been produced almost quantitatively on a 1 kg scale (it has been prepared also on a pilot scale, ca. 7 kg) and tested successfully for its ability to collect metal cations from different sources, such as ground water and mining process waters. Not only was this material highly efficient at collecting several metal ions out of solution it also proved to be regenerable and reusable over a number of adsorption/desorption, which is crucial for environmental friendliness. This material has several advantages compared to the currently used approaches, such as no need for any precipitation step.
Savelsbergh, Elwin R.; de Jong, Ton; Ferguson-Hessler, Monica G. M.
2011-01-01
Novice problem solvers are rather sensitive to surface problem features, and they often resort to trial and error formula matching rather than identifying an appropriate solution approach. These observations have been interpreted to imply that novices structure their knowledge according to surface features rather than according to problem type…
Chunggaze, M
1999-01-01
Monothiocarbamates M(OSCNEt sub 2) sub 2 M = Cd (1) Zn (2) analogous to the dithiocarbamates (Et sub 2 NCS sub 2) sub 2 M which have been extensively studied for metal-organic chemical vapour deposition (MOCVD), have been prepared as alternative single-source precursors for depositing II-VI semiconducting materials. Structural analysis of (1) revealed a new, O-binucleating, bonding mode for the monothiocarbamato ligand resulting in polymeric chains which are co-aligned to give a distorted close-packed hexagonal array. The mixed alkyl zinc derivative [Et sub 4 Zn sub 4 (OSCNEt sub 2) sub 2 (NEt sub 2) sub 2] is formed as the only isolable product from the reaction of EtZnNEt sub 2 with carbonyl sulfide and also exhibits a second new bonding mode for the monothiocarbamato ligand in which both the oxygen and sulfur atoms are binucleating. Uniform adherent films of CdS films with various morphologies were grown on GaAs(100) and glass at substrate temperatures between 350-450 deg C. No oxygen incorporation within ...
Large-Scale Bi-Level Strain Design Approaches and Mixed-Integer Programming Solution Techniques
Kim, Joonhoon; Reed, Jennifer L.; Maravelias, Christos T.
2011-01-01
The use of computational models in metabolic engineering has been increasing as more genome-scale metabolic models and computational approaches become available. Various computational approaches have been developed to predict how genetic perturbations affect metabolic behavior at a systems level, and have been successfully used to engineer microbial strains with improved primary or secondary metabolite production. However, identification of metabolic engineering strategies involving a large number of perturbations is currently limited by computational resources due to the size of genome-scale models and the combinatorial nature of the problem. In this study, we present (i) two new bi-level strain design approaches using mixed-integer programming (MIP), and (ii) general solution techniques that improve the performance of MIP-based bi-level approaches. The first approach (SimOptStrain) simultaneously considers gene deletion and non-native reaction addition, while the second approach (BiMOMA) uses minimization of metabolic adjustment to predict knockout behavior in a MIP-based bi-level problem for the first time. Our general MIP solution techniques significantly reduced the CPU times needed to find optimal strategies when applied to an existing strain design approach (OptORF) (e.g., from ∼10 days to ∼5 minutes for metabolic engineering strategies with 4 gene deletions), and identified strategies for producing compounds where previous studies could not (e.g., malate and serine). Additionally, we found novel strategies using SimOptStrain with higher predicted production levels (for succinate and glycerol) than could have been found using an existing approach that considers network additions and deletions in sequential steps rather than simultaneously. Finally, using BiMOMA we found novel strategies involving large numbers of modifications (for pyruvate and glutamate), which sequential search and genetic algorithms were unable to find. The approaches and solution
Large-scale bi-level strain design approaches and mixed-integer programming solution techniques.
Kim, Joonhoon; Reed, Jennifer L; Maravelias, Christos T
2011-01-01
The use of computational models in metabolic engineering has been increasing as more genome-scale metabolic models and computational approaches become available. Various computational approaches have been developed to predict how genetic perturbations affect metabolic behavior at a systems level, and have been successfully used to engineer microbial strains with improved primary or secondary metabolite production. However, identification of metabolic engineering strategies involving a large number of perturbations is currently limited by computational resources due to the size of genome-scale models and the combinatorial nature of the problem. In this study, we present (i) two new bi-level strain design approaches using mixed-integer programming (MIP), and (ii) general solution techniques that improve the performance of MIP-based bi-level approaches. The first approach (SimOptStrain) simultaneously considers gene deletion and non-native reaction addition, while the second approach (BiMOMA) uses minimization of metabolic adjustment to predict knockout behavior in a MIP-based bi-level problem for the first time. Our general MIP solution techniques significantly reduced the CPU times needed to find optimal strategies when applied to an existing strain design approach (OptORF) (e.g., from ∼10 days to ∼5 minutes for metabolic engineering strategies with 4 gene deletions), and identified strategies for producing compounds where previous studies could not (e.g., malate and serine). Additionally, we found novel strategies using SimOptStrain with higher predicted production levels (for succinate and glycerol) than could have been found using an existing approach that considers network additions and deletions in sequential steps rather than simultaneously. Finally, using BiMOMA we found novel strategies involving large numbers of modifications (for pyruvate and glutamate), which sequential search and genetic algorithms were unable to find. The approaches and solution
Large-scale bi-level strain design approaches and mixed-integer programming solution techniques.
Directory of Open Access Journals (Sweden)
Joonhoon Kim
Full Text Available The use of computational models in metabolic engineering has been increasing as more genome-scale metabolic models and computational approaches become available. Various computational approaches have been developed to predict how genetic perturbations affect metabolic behavior at a systems level, and have been successfully used to engineer microbial strains with improved primary or secondary metabolite production. However, identification of metabolic engineering strategies involving a large number of perturbations is currently limited by computational resources due to the size of genome-scale models and the combinatorial nature of the problem. In this study, we present (i two new bi-level strain design approaches using mixed-integer programming (MIP, and (ii general solution techniques that improve the performance of MIP-based bi-level approaches. The first approach (SimOptStrain simultaneously considers gene deletion and non-native reaction addition, while the second approach (BiMOMA uses minimization of metabolic adjustment to predict knockout behavior in a MIP-based bi-level problem for the first time. Our general MIP solution techniques significantly reduced the CPU times needed to find optimal strategies when applied to an existing strain design approach (OptORF (e.g., from ∼10 days to ∼5 minutes for metabolic engineering strategies with 4 gene deletions, and identified strategies for producing compounds where previous studies could not (e.g., malate and serine. Additionally, we found novel strategies using SimOptStrain with higher predicted production levels (for succinate and glycerol than could have been found using an existing approach that considers network additions and deletions in sequential steps rather than simultaneously. Finally, using BiMOMA we found novel strategies involving large numbers of modifications (for pyruvate and glutamate, which sequential search and genetic algorithms were unable to find. The approaches and
A dual-permeability approach to preferential water flow and solute transport in shrinking soils
Coppola, Antonio; dragonetti, giovanna; Comegna, Alessandro; Gerke, Horst H.; Basile, Angelo
2016-04-01
The pore systems in most natural soils is dynamically changing due to alternating swelling and shrinkage processes, which induces changes in pore volume and pore size distribution including deformations in pore geometry. This is a serious difficulty for modeling flow and transport in dual permeability approaches, as it will also require that the geometrical deformation of both the soil matrix and the fracture porous systems be taken into account, as well as the dynamics of soil hydraulic properties in response to the domain deformations. This study follows up a previous work by the same authors extending the classical rigid (RGD) approach formerly proposed by Gerke and van Genuchten, to account for shrinking effects (SHR) in modeling water flow and solute transport in dual-permeability porous media. In this study we considered three SHR scenarios, assuming that aggregate shrinkage may change either: (i) the hydraulic properties of the two pore domains, (ii) their relative fractions, and (iii) both, hydraulic properties and fractions of the two domains. The objective was to compare simulation results obtained under the RGD and the SHR assumptions to illustrate the impact of matrix volume changes on water storage, water fluxes and solute concentrations during: 1) An infiltration process bringing an initially dry soil to saturation, 2) A drainage process starting from an initially saturated soil. For an infiltration process, the simulated wetting front and the solute concentration propagation velocity, as well as the water fluxes, water and solute exchange rates, for the three SHR scenarios significantly deviated from the RGD. By contrast, relatively similar water content profiles evolved under all scenarios during drying. Overall, compared to the RGD approach, the effect of changing the hydraulic properties and the weight of the two domains according to the shrinkage behavior of the soil aggregates induced a much more rapid response in terms of water fluxes and
Entity Framework 4.0 Recipes A Problem-solution Approach
Tenny, L
2010-01-01
Entity Framework 4.0 Recipes provides an exhaustive collection of ready-to-use code solutions for Microsoft's Entity Framework, Microsoft's vision for the future of data access. Entity Framework is a model-centric data access platform with an ocean of new concepts and patterns for developers to learn. With this book, you will learn the core concepts of Entity Framework through a broad range of clear and concise solutions to everyday data access tasks. Armed with this experience, you will be ready to dive deep into Entity Framework, experiment with new approaches, and develop ways to solve even
Directory of Open Access Journals (Sweden)
Maria de Hoyos Guajardo, Ph.D. Candidate, M.Sc., B.Eng.
2004-11-01
Full Text Available The theory that is presented below aims to conceptualise how a group of undergraduate students tackle non-routine mathematical problems during a problem-solving course. The aim of the course is to allow students to experience mathematics as a creative process and to reflect on their own experience. During the course, students are required to produce a written ‘rubric’ of their work, i.e., to document their thoughts as they occur as well as their emotionsduring the process. These ‘rubrics’ were used as the main source of data.Students’ problem-solving processes can be explained as a three-stage process that has been called ‘solutioning’. This process is presented in the six sections below. The first three refer to a common area of concern that can be called‘generating knowledge’. In this way, generating knowledge also includes issues related to ‘key ideas’ and ‘gaining understanding’. The third and the fourth sections refer to ‘generating’ and ‘validating a solution’, respectively. Finally, once solutions are generated and validated, students usually try to improve them further before presenting them as final results. Thus, the last section deals with‘improving a solution’. Although not all students go through all of the stages, it may be said that ‘solutioning’ considers students’ main concerns as they tackle non-routine mathematical problems.
Yamaguchi, Yuji; Suzuki, Mitsuharu; Motoyama, Takao; Sugii, Shuhei; Katagiri, Chiho; Takahira, Katsuya; Ikeda, Shinya; Yamada, Hiroko; Nakayama, Ken-ichi
2014-01-01
The vertical composition profile of active layer has a major effect on the performance of organic photovoltaic devices (OPVs). While stepwise deposition of different materials is a conceptually straightforward method for controlled preparation of multi-component active layers, it is practically challenging for solution processes because of dissolution of the lower layer. Herein, we overcome this difficulty by employing the photoprecursor approach, in which a soluble photoprecursor is solution-deposited then photoconverted in situ to a poorly soluble organic semiconductor. This approach enables solution-processing of the p-i-n triple-layer architecture that has been suggested to be effective in obtaining efficient OPVs. We show that, when 2,6-dithienylanthracene and a fullerene derivative PC71BM are used as donor and acceptor, respectively, the best p-i-n OPV affords a higher photovoltaic efficiency than the corresponding p-n device by 24% and bulk-heterojunction device by 67%. The photoprecursor approach is also applied to preparation of three-component p-i-n films containing another donor 2,6-bis(5′-(2-ethylhexyl)-(2,2′-bithiophen)-5-yl)anthracene in the i-layer to provide a nearly doubled efficiency as compared to the original two-component p-i-n system. These results indicate that the present approach can serve as an effective means for controlled preparation of well-performing multi-component active layers in OPVs and related organic electronic devices. PMID:25413952
Directory of Open Access Journals (Sweden)
Mulawarman Mulawarman
2016-12-01
Full Text Available Career adaptability is the preparedness role in work and adjustman to changes in working situation in the future. The purpose of this study was to examine Solution Focused Brief Counseling (SFBC approach in developing career adaptability of students.The method used in this study was a mix method . Subjects selected through a purposive sampling method that is focused on graduate students at the beginning of the semester with a major in Guidance and Counseling Faculty of Education, Semarang State University. Career adaptability in this study consists of four dimensions, concern, control, curiosity and confidence. Stages of Solution Focused Brief Counseling (SFBC implemented include establishing relationships, Identifying a solvable complaint, Establishing goals, Designing and Implementing Intervention, and termination, evaluation, and follow-up. The results of this study showed Solution Focused Brief Counseling (SFBC is effective in improving the adaptability of student career both qualitatively and quantitatively.
Georgescu, M.; Chow, W. T. L.; Wang, Z. H.; Brazel, A.; Trapido-Lurie, B.; Roth, M.; Benson-Lira, V.
2015-06-01
Because of a projected surge of several billion urban inhabitants by mid-century, a rising urgency exists to advance local and strategically deployed measures intended to ameliorate negative consequences on urban climate (e.g., heat stress, poor air quality, energy/water availability). Here we highlight the importance of incorporating scale-dependent built environment induced solutions within the broader umbrella of urban sustainability outcomes, thereby accounting for fundamental physical principles. Contemporary and future design of settlements demands cooperative participation between planners, architects, and relevant stakeholders, with the urban and global climate community, which recognizes the complexity of the physical systems involved and is ideally fit to quantitatively examine the viability of proposed solutions. Such participatory efforts can aid the development of locally sensible approaches by integrating across the socioeconomic and climatic continuum, therefore providing opportunities facilitating comprehensive solutions that maximize benefits and limit unintended consequences.
Batinas, Aurora A.; Dam, Jeroen; Meetsma, Auke; Hessen, Bart; Bouwkamp, Marco W.
2010-01-01
Thermolysis of half-sandwich vanadium imido complexes Cp(RN)V(i-Pr(2)N)Me (R = p-Tol, 1a; R = t-Bu, 1b) results in a mixture of products, including vanadium(IV) dimers [CpVMe](2)(mu-RN)(2), i-Pr(2)NH, i-PrNCMe(2), CH(4), and one or more paramagnetic species. In the presence of dmpe (dmpe =
Ju, Jianhua; Lim, Si-Kyu; Jiang, Hui; Seo, Jeong-Woo; Her, Yeng; Shen, Ben
2008-01-01
Thermolysis of iso-migrastatin (1) under neat heating conditions afforded migrastatin (1a). The reaction is proposed to proceed via a concerted [3,3]-sigmatropic rearrangement by which ring expansion is achieved regio- and enantio-specifically. The general applicability of this reaction was demonstrated with six additional iso-migrastatin congeners (3 – 8), providing a new route to the synthesis of migrastatin analogs (3a – 8a). PMID:17134292
Ju, Jianhua; Lim, Si-Kyu; Jiang, Hui; Seo, Jeong-Woo; Her, Yeng; Shen, Ben
2006-12-07
Thermolysis of isomigrastatin (1) under neat heating conditions afforded migrastatin (1a). The reaction is proposed to proceed via a concerted [3,3]-sigmatropic rearrangement by which ring expansion is achieved regio- and enantiospecifically. The general applicability of this reaction was demonstrated with six additional isomigrastatin congeners (3-8), providing a new route to the synthesis of migrastatin analogues (3a-8a). [reaction: see text
A new mathematical approach for shock-wave solution in a dusty plasma
Energy Technology Data Exchange (ETDEWEB)
Das, G.C.; Dwivedi, C.B. [Plasma Physics Division, Institute of Advanced Study in Science and Technology, Khanapara, Guwahati-781022, Assam (India); Talukdar, M. [Computer Science Division, Institute of Advanced Study in Science and Technology, Khanapara, Guwahati-781022, Assam (India); Sarma, J. [Department of Mathematics, R. G. Baruah College, Guwahati-781025, Assam (India)
1997-12-01
The problem of nonlinear Burger equation in a plasma contaminated with heavy dust grains has been revisited. As discussed earlier [C. B. Dwivedi and B. P. Pandey, Phys. Plasmas {bold 2}, 9 (1995)], the Burger equation originates due to dust charge fluctuation dynamics. A new alternate mathematical approach based on a simple traveling wave formalism has been applied to find out the solution of the derived Burger equation, and the method recovers the known shock-wave solution. This technique, although having its own limitation, predicts successfully the salient features of the weak shock-wave structure in a dusty plasma with dust charge fluctuation dynamics. It is emphasized that this approach of the traveling wave formalism is being applied for the first time to solve the nonlinear wave equation in plasmas. {copyright} {ital 1997 American Institute of Physics.}
A new approach to the regularization of regional gravity field solutions in SRBF
Naeimi, Majid; Flury, Jakob
2016-04-01
We present a purely data-dependent approach to the choice of the regularization parameter for regional gravity field solutions in spherical radial base functions. The method is based on the space-localization feature of the base functions and needs a prior gravity field solution to solve for the regional gravity field coefficients. However, to be independent of any prior model, we estimate an approximate solution using a realistic first guess for the regularization parameter. The final regularization parameter and therefore the final regional solution are obtained in an iterative procedure. We apply our methodology to real GOCE gravity gradients and assess the performance of the method in several test regions. Results show that our approach outperforms the existing methods such as the L-curve, the GCV and the VCE. In addition, the estimated coefficients represent the shape of the signal (geoid) in the target region and have therefore physical meaning. More details are given and the results are discussed in this contribution.
A hybrid solution approach for a multi-objective closed-loop logistics network under uncertainty
Mehrbod, Mehrdad; Tu, Nan; Miao, Lixin
2014-09-01
The design of closed-loop logistics (forward and reverse logistics) has attracted growing attention with the stringent pressures of customer expectations, environmental concerns and economic factors. This paper considers a multi-product, multi-period and multi-objective closed-loop logistics network model with regard to facility expansion as a facility location-allocation problem, which more closely approximates real-world conditions. A multi-objective mixed integer nonlinear programming formulation is linearized by defining new variables and adding new constraints to the model. By considering the aforementioned model under uncertainty, this paper develops a hybrid solution approach by combining an interactive fuzzy goal programming approach and robust counterpart optimization based on three well-known robust counterpart optimization formulations. Finally, this paper compares the results of the three formulations using different test scenarios and parameter-sensitive analysis in terms of the quality of the final solution, CPU time, the level of conservatism, the degree of closeness to the ideal solution, the degree of balance involved in developing a compromise solution, and satisfaction degree.
DEFF Research Database (Denmark)
Petersen, Hanne Løhmann; Madsen, Oli B.G.
2009-01-01
This paper introduces the double travelling salesman problem with multiple stacks and presents four different metaheuristic approaches to its solution. The double TSP with multiple stacks is concerned with determining the shortest route performing pickups and deliveries in two separated networks...... different neighbourhood structures are developed for the problem and used with each of three local search metaheuristics. Additionally some simpler removal and reinsertion operators are used in a Large neighbourhood search framework. Finally some computational results are given along with lower bounds...
Computational Approach for Studying Optical Properties of DNA Systems in Solution
DEFF Research Database (Denmark)
Nørby, Morten Steen; Steinmann, Casper; Olsen, Jógvan Magnus Haugaard
2016-01-01
In this paper we present a study of the methodological aspects regarding calculations of optical properties for DNA systems in solution. Our computational approach will be built upon a fully polarizable QM/MM/Continuum model within a damped linear response theory framework. In this approach...... the environment is given a highly advanced description in terms of the electrostatic potential through the polarizable embedding model. Furthermore, bulk solvent effects are included in an efficient manner through a conductor-like screening model. With the aim of reducing the computational cost we develop a set...
A new approach to study cadmium complexes with oxalic acid in soil solution
Energy Technology Data Exchange (ETDEWEB)
Jaklova Dytrtova, Jana, E-mail: dytrtova@uochb.cas.cz [Institute of Organic Chemistry and Biochemistry of the AS CR, v.v.i., Flemingovo namesti 2, 16610 Prague 6 (Czech Republic); Jakl, Michal [Department of Agro-Environmental Chemistry and Plant Nutrition, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamycka 129, 16521 Prague - Suchdol (Czech Republic); Sestakova, Ivana [J. Heyrovsky Institute of Physical Chemistry of the AS CR, v.v.i., Dolejskova 3, 182 23 Prague 8 (Czech Republic); Zins, Emilie-Laure; Schroeder, Detlef [Institute of Organic Chemistry and Biochemistry of the AS CR, v.v.i., Flemingovo namesti 2, 16610 Prague 6 (Czech Republic); Navratil, Tomas [J. Heyrovsky Institute of Physical Chemistry of the AS CR, v.v.i., Dolejskova 3, 182 23 Prague 8 (Czech Republic)
2011-05-05
This study presents a new analytical approach for the determination of heavy metals complexed to low-molecular-weight-organic acids in soil solutions, which combines the sensitivity of differential pulse anodic stripping voltammetry (DPASV) with the molecular insight gained by electrospray ionization mass spectrometry (ESI-MS). The combination of these analytical methods allows the investigation of such complexes in complex matrixes. On the voltammograms of the soil solutions, in addition to the expected complexes of oxalic acid with cadmium and lead, respectively, also peaks belonging to mixed complexes of cadmium, lead, and oxalic acid (OAH{sub 2}) were observed. In order to verify the possible formation of complexes with OAH{sub 2}, aqueous solutions of OAH{sub 2} with traces of Cd(II) were investigated as model systems. Signals corresponding to several distinct molecular complexes between cadmium and oxalic acid were detected in the model solutions using negative-ion ESI-MS, which follow the general formula [Cd{sub n}(X,Y){sub (2n+1)}]{sup -}, where n is the number of cadmium atoms, X = Cl{sup -}, and Y = OAH{sup -}. Some of these complexes were also identified in the ESI mass spectra taken from the soil solutions.
A Solution-Based Approach for Mo-99 Production: Considerations for Nitrate versus Sulfate Media
Directory of Open Access Journals (Sweden)
Amanda J. Youker
2013-01-01
Full Text Available Molybdenum-99 is the parent of Technetium-99m, which is used in nearly 80% of all nuclear medicine procedures. The medical community has been plagued by Mo-99 shortages due to aging reactors, such as the NRU (National Research Universal reactor in Canada. There are currently no US producers of Mo-99, and NRU is scheduled for shutdown in 2016, which means that another Mo-99 shortage is imminent unless a potential domestic Mo-99 producer fills the void. Argonne National Laboratory is assisting two potential domestic suppliers of Mo-99 by examining the effects of a uranyl nitrate versus a uranyl sulfate target solution configuration on Mo-99 production. Uranyl nitrate solutions are easier to prepare and do not generate detectable amounts of peroxide upon irradiation, but a high radiation field can lead to a large increase in pH, which can lead to the precipitation of fission products and uranyl hydroxides. Uranyl sulfate solutions are more difficult to prepare, and enough peroxide is generated during irradiation to cause precipitation of uranyl peroxide, but this can be prevented by adding a catalyst to the solution. A titania sorbent can be used to recover Mo-99 from a highly concentrated uranyl nitrate or uranyl sulfate solution; however, different approaches must be taken to prevent precipitation during Mo-99 production.
A functional integral approach to shock wave solutions of Euler equations with spherical symmetry
Yang, Tong
1995-08-01
For n×n systems of conservation laws in one dimension without source terms, the existence of global weak solutions was proved by Glimm [1]. Glimm constructed approximate solutions using a difference scheme by solving a class of Riemann problems. In this paper, we consider the Cauchy problem for the Euler equations in the spherically symmetric case when the initial data are small perturbations of the trivial solution, i.e., u≡0 and ρ≡ constant, where u is velocity and ρ is density. We show that this Cauchy problem can be reduced to an ideal nonlinear problem approximately. If we assume all the waves move at constant speeds in the ideal problem, by using Glimm's scheme and an integral approach to sum the contributions of the reflected waves that correspond to each path through the solution, we get uniform bounds on the L ∞ norm and total variational norm of the solutions for all time. The geometric effects of spherical symmetry leads to a non-integrable source term in the Euler equations. Correspondingly, we consider an infinite reflection problem and solve it by considering the cancellations between reflections of different orders in our ideal problem. Thus we view this as an analysis of the interaction effects at the quadratic level in a nonlinear model problem for the Euler equations. Although it is far more difficult to obtain estimates in the exact solutions of the Euler equations due to the problem of controlling the time at which the cancellations occur, we believe that this analysis of the wave behaviour will be the first step in solving the problem of existence of global weak solutions for the spherically symmetric Euler equations outside of fixed ball.
Energy Technology Data Exchange (ETDEWEB)
Tumelero, Fernanda, E-mail: fernanda.tumelero@yahoo.com.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Petersen, Claudio Z.; Goncalves, Glenio A.; Lazzari, Luana, E-mail: claudiopeteren@yahoo.com.br, E-mail: gleniogoncalves@yahoo.com.br, E-mail: luana-lazzari@hotmail.com [Universidade Federal de Pelotas (DME/UFPEL), Capao do Leao, RS (Brazil). Instituto de Fisica e Matematica
2015-07-01
In this work, we present a solution of the Neutron Point Kinetics Equations with temperature feedback effects applying the Polynomial Approach Method. For the solution, we consider one and six groups of delayed neutrons precursors with temperature feedback effects and constant reactivity. The main idea is to expand the neutron density, delayed neutron precursors and temperature as a power series considering the reactivity as an arbitrary function of the time in a relatively short time interval around an ordinary point. In the first interval one applies the initial conditions of the problem and the analytical continuation is used to determine the solutions of the next intervals. With the application of the Polynomial Approximation Method it is possible to overcome the stiffness problem of the equations. In such a way, one varies the time step size of the Polynomial Approach Method and performs an analysis about the precision and computational time. Moreover, we compare the method with different types of approaches (linear, quadratic and cubic) of the power series. The answer of neutron density and temperature obtained by numerical simulations with linear approximation are compared with results in the literature. (author)
Synthesis of Co-Doped CdS Nanocrystals by Direct Thermolysis of Cadmium and Cobalt Thiolate Clusters
Directory of Open Access Journals (Sweden)
Jianing Zhao
2015-01-01
Full Text Available Co-doped CdS (Co:CdS nanocrystals with controllable morphology (quantum dots and nanorods were easily synthesized by direct thermolysis of (Me4N2[Co4(SC6H510] and (Me4N4[S4Cd10(SPh16] under different precursor concentration, in virtue of the ions exchange of molecular clusters. The Co:CdS quantum dots were produced under low precursor concentration, and the Co:CdS nanorods could be obtained under higher precursor concentration. The Co-doping effect on the structure, growth process, and property of CdS nanocrystals was also investigated. The results indicated that the Co-doping was favorable for the formation of the nanorod structures for a short reaction time. In addition, the Co-doping in the CdS lattice resulted in the ferromagnetic property of the Co:CdS quantum dots at room temperature. Moreover, compared with the CdS quantum dots, the Co:CdS quantum dots exhibited obvious quantum confinement effect and photoluminescence emission with slightly red-shift.
Zijp, Michiel C; Posthuma, Leo; Wintersen, Arjen; Devilee, Jeroen; Swartjes, Frank A
2016-05-01
This paper introduces Solution-focused Sustainability Assessment (SfSA), provides practical guidance formatted as a versatile process framework, and illustrates its utility for solving a wicked environmental management problem. Society faces complex and increasingly wicked environmental problems for which sustainable solutions are sought. Wicked problems are multi-faceted, and deriving of a management solution requires an approach that is participative, iterative, innovative, and transparent in its definition of sustainability and translation to sustainability metrics. We suggest to add the use of a solution-focused approach. The SfSA framework is collated from elements from risk assessment, risk governance, adaptive management and sustainability assessment frameworks, expanded with the 'solution-focused' paradigm as recently proposed in the context of risk assessment. The main innovation of this approach is the broad exploration of solutions upfront in assessment projects. The case study concerns the sustainable management of slightly contaminated sediments continuously formed in ditches in rural, agricultural areas. This problem is wicked, as disposal of contaminated sediment on adjacent land is potentially hazardous to humans, ecosystems and agricultural products. Non-removal would however reduce drainage capacity followed by increased risks of flooding, while contaminated sediment removal followed by offsite treatment implies high budget costs and soil subsidence. Application of the steps in the SfSA-framework served in solving this problem. Important elements were early exploration of a wide 'solution-space', stakeholder involvement from the onset of the assessment, clear agreements on the risk and sustainability metrics of the problem and on the interpretation and decision procedures, and adaptive management. Application of the key elements of the SfSA approach eventually resulted in adoption of a novel sediment management policy. The stakeholder
Directory of Open Access Journals (Sweden)
Leandro Freire dos Santos
2017-08-01
Full Text Available Whey is the liquid that results from the coagulation of milk during cheese manufacture. Cheese whey is also an important environmental pollution source. The present experiment sought to compare β-galactosidase (EC 3.2.1.23 production by Aspergillus oryzae from deproteinized and un-deproteinized CWP solutions. β-galactosidase was produced by submerged fermentation in deproteinized or un-deproteinized CWP solutions. To determine the activity of the enzyme, a reaction mixture containing cell-free extract and ortho Nitrophenyl β galactoside (ONPG was used. The results indicated that β-galactosidase induction was greater when using deproteinized CWP solution compared to the un deproteinized CWP solution. These results may enable an alternative management of cheese whey, thereby decreasing its impact on the environment and producing value-added biomacromolecules.
Leandro Freire dos Santos; Cibely Maria Gonçalves; Priscila Lumi Ishii; Hélio Hiroshi Suguimoto
2017-01-01
Whey is the liquid that results from the coagulation of milk during cheese manufacture. Cheese whey is also an important environmental pollution source. The present experiment sought to compare β-galactosidase (EC 3.2.1.23) production by Aspergillus oryzae from deproteinized and un-deproteinized CWP solutions. β-galactosidase was produced by submerged fermentation in deproteinized or un-deproteinized CWP solutions. To determine the activity of the enzyme, a reaction mixture containing cell-fr...
Solution approach for a large scale personnel transport system for a large company in Latin America
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Eduardo-Arturo Garzón-Garnica
2017-10-01
Full Text Available Purpose: The present paper focuses on the modelling and solution of a large-scale personnel transportation system in Mexico where many routes and vehicles are currently used to service 525 points. The routing system proposed can be applied to many cities in the Latin-American region. Design/methodology/approach: This system was modelled as a VRP model considering the use of real-world transit times, and the fact that routes start at the farthest point from the destination center. Experiments were performed on different sized sets of service points. As the size of the instances was increased, the performance of the heuristic method was assessed in comparison with the results of an exact algorithm, the results remaining very close between both. When the size of the instance was full-scale and the exact algorithm took too much time to solve the problem, then the heuristic algorithm provided a feasible solution. Supported by the validation with smaller scale instances, where the difference between both solutions was close to a 6%, the full –scale solution obtained with the heuristic algorithm was considered to be within that same range. Findings: The proposed modelling and solving method provided a solution that would produce significant savings in the daily operation of the routes. Originality/value: The urban distribution of the cities in Latin America is unique to other regions in the world. The general layout of the large cities in this region includes a small town center, usually antique, and a somewhat disordered outer region. The lack of a vehicle-centered urban planning poses distinct challenges for vehicle routing problems in the region. The use of a heuristic VRP combined with the results of an exact VRP, allowed the obtention of an improved routing plan specific to the requirements of the region.
Solution based approaches for the morphology control of BaTiO3 particulates
Florentina Maxim; Paula Ferreira; Paula M. Vilarinho; Ian Reaney; Anne Aimable; Paul Bowen
2010-01-01
Within the action COST 539 - ELENA our contribution was aimed at studying solution based approaches for the morphology control of BaTiO3 particulates. Initially, our kinetic analysis and systematic structural and morphological studies, demonstrated that during hydrothermal synthesis from layered titanate nanotubes (TiNTS), BaTiO3 forms via two mechanisms depending on the temperature and time. At low temperatures (90°C), “wild” type BaTiO3 dendritic particles with cubic structure were formed t...
SU-E-T-619: A Network-Flow Solution Approach to VMAT Treatment Plan Optimization.
Salari, E; Craft, D
2012-06-01
To add mathematical rigor to the merging phase of the recently published two-stage VMAT optimization method called VMERGE. Using an exact merging method, we are able to better characterize the tradeoff between delivery efficiency and dose quality. VMERGE begins with an IMRT plan that uses 180 equi-spaced beams and yields the "ideal" dose. Neighboring fluence maps are successively merged, meaning they are added together and delivered as one map. The merging process improves the delivery time at the expense of deviating from the initial high-quality dose distribution. We replace the original heuristic merging method by considering the merging problem as a bi-criteria optimization problem: maximize treatment efficiency and minimize the deviation from the ideal dose. We formulate this using a network-flow model where nodes represent the beam angles along with the starting MLC leaf position and arcs represent the possible merges. Since the problem is non-convex, we employ a customized box algorithm to obtain the Pareto approximation. We also evaluate the performance of several simple heuristics. We test our exact and heuristic solution approaches on a pancreas and a prostate case. For both cases, the shape of the Pareto frontier suggests that starting from a high quality plan, we can obtain efficient VMAT plans through merging neighboring arcs without substantially deviating from the initial dose distribution. The trade-off curves obtained by the various heuristics are contrasted and shown to all be equally capable of initial plan simplifications, but to deviate in quality for more drastic efficiency improvements. This work presents a bi-criteria network-flow solution approach to the merging problem. The obtained Pareto-frontier approximation is used as a benchmark to evaluate the performance of the proposed merging heuristics. The results validate that one of the heuristics in particular can achieve high-quality solutions. © 2012 American Association of Physicists in
Zhou, Shenggao; Sun, Hui; Cheng, Li-Tien; Dzubiella, Joachim; McCammon, J. Andrew
2016-01-01
Recent years have seen the initial success of a variational implicit-solvent model (VISM), implemented with a robust level-set method, in capturing efficiently different hydration states and providing quantitatively good estimation of solvation free energies of biomolecules. The level-set minimization of the VISM solvation free-energy functional of all possible solute-solvent interfaces or dielectric boundaries predicts an equilibrium biomolecular conformation that is often close to an initial guess. In this work, we develop a theory in the form of Langevin geometrical flow to incorporate solute-solvent interfacial fluctuations into the VISM. Such fluctuations are crucial to biomolecular conformational changes and binding process. We also develop a stochastic level-set method to numerically implement such a theory. We describe the interfacial fluctuation through the “normal velocity” that is the solute-solvent interfacial force, derive the corresponding stochastic level-set equation in the sense of Stratonovich so that the surface representation is independent of the choice of implicit function, and develop numerical techniques for solving such an equation and processing the numerical data. We apply our computational method to study the dewetting transition in the system of two hydrophobic plates and a hydrophobic cavity of a synthetic host molecule cucurbit[7]uril. Numerical simulations demonstrate that our approach can describe an underlying system jumping out of a local minimum of the free-energy functional and can capture dewetting transitions of hydrophobic systems. In the case of two hydrophobic plates, we find that the wavelength of interfacial fluctuations has a strong influence to the dewetting transition. In addition, we find that the estimated energy barrier of the dewetting transition scales quadratically with the inter-plate distance, agreeing well with existing studies of molecular dynamics simulations. Our work is a first step toward the
Directory of Open Access Journals (Sweden)
Nadezhda M. Zholobak
2016-12-01
Full Text Available Luminescent organic dots (O-dots were synthesized via a one-pot, solvent-free thermolysis of citric acid in urea melt. The influence of the ratio of the precursors and the duration of the process on the properties of the O-dots was established and a mechanism of their formation was hypothesized. The multicolour luminescence tunability and toxicity of synthesized O-dots were extensively studied. The possible applications of O-dots for alive/fixed cell staining and labelling of layer-by-layer polyelectrolyte microcapsules were evaluated.
Singer, B. Sh.
2008-12-01
The paper presents a new code for modelling electromagnetic fields in complicated 3-D environments and provides examples of the code application. The code is based on an integral equation (IE) for the scattered electromagnetic field, presented in the form used by the Modified Iterative Dissipative Method (MIDM). This IE possesses contraction properties that allow it to be solved iteratively. As a result, for an arbitrary earth model and any source of the electromagnetic field, the sequence of approximations converges to the solution at any frequency. The system of linear equations that represents a finite-dimensional counterpart of the continuous IE is derived using a projection definition of the system matrix. According to this definition, the matrix is calculated by integrating the Green's function over the `source' and `receiver' cells of the numerical grid. Such a system preserves contraction properties of the continuous equation and can be solved using the same iterative technique. The condition number of the system matrix and, therefore, the convergence rate depends only on the physical properties of the model under consideration. In particular, these parameters remain independent of the numerical grid used for numerical simulation. Applied to the system of linear equations, the iterative perturbation approach generates a sequence of approximations, converging to the solution. The number of iterations is significantly reduced by finding the best possible approximant inside the Krylov subspace, which spans either all accumulated iterates or, if it is necessary to save the memory, only a limited number of the latest iterates. Optimization significantly reduces the number of iterates and weakens its dependence on the lateral contrast of the model. Unlike more traditional conjugate gradient approaches, the iterations are terminated when the approximate solution reaches the requested relative accuracy. The number of the required iterates, which for simple
Kulkarni, P B; Purandare, G N; Nair, J K; Talawar, M B; Mukundan, T; Asthana, S N
2005-03-17
The lithium (Li) and potassium (K) salts of 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4,6-trinitroanilino benzoic acid (TABA) were prepared and characterized during this work. The synthesis was carried out by addition of a solution of lithium/potassium hydroxide to the aqueous solution of NTO and TABA, respectively. The products were characterized by elemental analysis, metal content determination and Fourier Transform Infrared (FTIR) Spectrum. Differential scanning calorimetry (DSC) profile indicated that Li and K salts of NTO and TABA undergo exothermic decomposition in the temperature range of 257-360 degrees C suggesting their energetic nature. The thermo gravimetric (TG) weight loss pattern revealed loss of water for Li/K salts of NTO and TABA in the temperature range of 115-155 degrees C. Sensitivity results revealed that the compounds are insensitive to impact and friction (impact sensitivity--height of 50% explosion>170 cm and friction insensitivity up to 36 kg) stimuli despite even the parent molecule of NTO salts (NTO) being HEM in the hazard category of 1.1. The FTIR spectra of the gaseous products evolved during TGA of NTO and TABA salts indicated the release of NO2. The formation of products such as LiNCO and KNCO was also observed in case of NTO salts, whereas that of CO2 and NH containing products was indicated in case of TABA salts during this study. In order to assess the performance as energetic ballistic modifiers (EBMs), NTO and TABA salts were incorporated in the ammonium perchlorate-hydroxyl terminated polybutadiene (AP-HTPB) composite propellants. The potassium salts enhanced the burning rate of the propellant. The best catalytic effect was obtained with K-TABA salt, which increased the burning rate to the extent of approximately 81% as well as brought down the n-value to 0.15 (pressure 2-9 MPa).
Giovannini, Tommaso; Olszòwka, Marta; Cappelli, Chiara
2016-11-08
We propose a methodology, based on the combination of classical Molecular Dynamics (MD) simulations with a fully polarizable Quantum Mechanical (QM)/Molecular Mechanics (MM)/Polarizable Continuum Model (PCM) Hamiltonian, to calculate Vibrational Circular Dichroism (VCD) spectra of chiral systems in aqueous solution. Polarization effects are included in the MM force field by exploiting an approach based on Fluctuating Charges (FQ). By performing the MD, the description of the solvating environment is enriched by taking into account the dynamical aspects of the solute-solvent interactions. On the other hand, the QM/FQ/PCM calculation of the VCD spectrum ensures an accurate description of the electronic density of the solute and a proper account for the specific interactions in solution. The application of our approach to (R)-methyloxirane and (l)-alanine in aqueous solution gives calculated spectra in remarkable agreement with their experimental counterparts and a substantial improvement with respect to the same spectra calculated with the PCM.
Computational Approaches to Modeling Artificial Emotion -– An overview of the Proposed Solutions
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Zdzislaw eKOWALCZUK
2016-04-01
Full Text Available Cybernetic approach to modeling artificial emotion through the use of different theories of psychology is considered in this paper, presenting a review of twelve proposed solutions: ActAffAct, FLAME, EMA, ParleE, FearNot!, FAtiMA, WASABI, Cathexis, KARO, MAMID, FCM, and xEmotion. The main motivation for this study is founded on the hypothesis that emotions can play a definite utility role of scheduling variables in the construction of intelligent autonomous systems, agents and mobile robots. In this review we also include an innovative and panoptical, comprehensive system, referred to as the Intelligent System of Decision-making (ISD, which has been employed in practical applications of various autonomous units, and which applies as its part the xEmotion, taking into consideration the personal aspects of emotions, affects (short term emotions and mood (principally, long term emotions.
Allen, Patricia E; Armstrong, Myrna L; Saladiner, Jason E; Hamilton, Mary Jane; Conard, Patricia L
2014-01-01
Capitalizing on the almost 2.2 million service members returning from Operation Iraqi Freedom and New Dawn (OIF) in Iraq, and Operation Enduring Freedom (OEF) in Afghanistan, baccalaureate educators are encouraged to create realistic, applicable nursing transitional programs for the health and health-related oriented military veterans. Opportunities, hurdles, and solutions related to the veteran's unique socio-economic circumstances of education, finances, and advisement are provided so the potential veteran student is successful within the university's milieu. Transitional nursing educational interventions related to assessment, didactic, and clinical used by two baccalaureate nursing curriculums, including the eLineMilitary* (ELM) Program, provide approaches of how to propel the veteran's journey toward graduation in a professional nursing program. These interventions include modular didactic, competency based education, as well as the concentrated, collegial time within the Faculty/Clinical Coach triad for essential role modeling, care, and skills. Copyright © 2014 Elsevier Inc. All rights reserved.
Monitoring Approach to Evaluate the Performances of a New Deposition Nozzle Solution for DED Systems
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Federico Mazzucato
2017-05-01
Full Text Available Abstract: In order to improve the process efficiency of a direct energy deposition (DED system, closed loop control systems can be considered for monitoring the deposition and melting processes and adjusting the process parameters in real-time. In this paper, the monitoring of a new deposition nozzle solution for DED systems is approached through a simulation-experimental comparison. The shape of the powder flow at the exit of the nozzle outlet and the spread of the powder particles on the deposition plane are analyzed through 2D images of the powder flow obtained by monitoring the powder depositions with a high-speed camera. These experimental results are then compared with data obtained through a Computational Fluid Dynamics model. Preliminary tests are carried out by varying powder, carrier, and shielding mass flow, demonstrating that the last parameter has a significant influence on the powder distribution and powder flow geometry.
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Heydari Majeed
2017-03-01
Full Text Available Nowadays market basket analysis is one of the interested research areas of the data mining that has received more attention by researchers. But, most of the related research focused on the traditional and heuristic algorithms with limited factors that are not the only influential factors of the basket market analysis. In this paper to efficient modeling and analysis of the market basket data, the optimization model is proposed with considering allocation parameter as one of the important and effectual factors of the selling rate. The genetic algorithm approach is applied to solve the formulated non-linear binary programming problem and a numerical example is used to illustrate the presented model. The provided results reveal that the obtained solutions seem to be more realistic and applicable.
Applying a solution-focused approach to support a worker who is under stress.
Mishima, Norio; Kubota, Shinya; Nagata, Shoji
2005-06-01
The solution-focused approach (SFA) developed by Insoo Kim Berg and Steve de Shazer at the Brief Family Therapy Center, Milwaukee, USA is classified as brief psychotherapy. We believe that SFA can give an occupational healthcare staff useful tools that will positively influence their relationships with workers, because it focuses on workers' strengths rather than their weaknesses when the staff interviews them using SFA. In this report, we explain the case of a worker who was under stress and was interviewed using SFA. Although the worker came to the interview because of his physical symptoms, he disclosed that he was under considerable stress at work and that his main concern was his relationship with his superior. One of the authors interviewed him using SFA. In the interview the worker discovered his own resources and strengths, and finally defined his goal. In the end, he discovered solutions by himself, and has been doing well in follow-up. We describe this process in detail, and discuss potential applications of SFA in occupational medicine.
Experiments with ROPAR, an approach for probabilistic analysis of the optimal solutions' robustness
Marquez, Oscar; Solomatine, Dimitri
2016-04-01
Robust optimization is defined as the search for solutions and performance results which remain reasonably unchanged when exposed to uncertain conditions such as natural variability in input variables, parameter drifts during operation time, model sensitivities and others [1]. In the present study we follow the approach named ROPAR (multi-objective robust optimization allowing for explicit analysis of robustness (see online publication [2]). Its main idea is in: a) sampling the vectors of uncertain factors; b) solving MOO problem for each of them obtaining multiple Pareto sets; c) analysing the statistical properties (distributions) of the subsets of these Pareto sets corresponding to different conditions (e.g. based on constraints formulated for the objective functions values of other system variables); d) selecting the robust solutions. The paper presents the results of experiments with the two case studies: 1) a benchmark function ZDT1 (with an uncertain factor) often used in algorithms comparisons, and 2) a problem of drainage network rehabilitation that uses SWMM hydrodynamic model (the rainfall is assumed to be an uncertain factor). This study is partly supported by the FP7 European Project WeSenseIt Citizen Water Observatory (www.http://wesenseit.eu/) and the CONACYT (Mexico's National Council of Science and Technology) supporting the PhD study of the first author. References [1] H.G.Beyer and B. Sendhoff. "Robust optimization - A comprehensive survey." Comput. Methods Appl. Mech. Engrg., 2007: 3190-3218. [2] D.P. Solomatine (2012). An approach to multi-objective robust optimization allowing for explicit analysis of robustness (ROPAR). UNESCO-IHE. Online publication. Web: https://www.unesco-ihe.org/sites/default/files/solomatine-ropar.pdf
Multi-period natural gas market modeling Applications, stochastic extensions and solution approaches
Egging, Rudolf Gerardus
This dissertation develops deterministic and stochastic multi-period mixed complementarity problems (MCP) for the global natural gas market, as well as solution approaches for large-scale stochastic MCP. The deterministic model is unique in the combination of the level of detail of the actors in the natural gas markets and the transport options, the detailed regional and global coverage, the multi-period approach with endogenous capacity expansions for transportation and storage infrastructure, the seasonal variation in demand and the representation of market power according to Nash-Cournot theory. The model is applied to several scenarios for the natural gas market that cover the formation of a cartel by the members of the Gas Exporting Countries Forum, a low availability of unconventional gas in the United States, and cost reductions in long-distance gas transportation. 1 The results provide insights in how different regions are affected by various developments, in terms of production, consumption, traded volumes, prices and profits of market participants. The stochastic MCP is developed and applied to a global natural gas market problem with four scenarios for a time horizon until 2050 with nineteen regions and containing 78,768 variables. The scenarios vary in the possibility of a gas market cartel formation and varying depletion rates of gas reserves in the major gas importing regions. Outcomes for hedging decisions of market participants show some significant shifts in the timing and location of infrastructure investments, thereby affecting local market situations. A first application of Benders decomposition (BD) is presented to solve a large-scale stochastic MCP for the global gas market with many hundreds of first-stage capacity expansion variables and market players exerting various levels of market power. The largest problem solved successfully using BD contained 47,373 variables of which 763 first-stage variables, however using BD did not result in
Energy Technology Data Exchange (ETDEWEB)
Egging, R.G.
2010-11-15
This dissertation develops deterministic and stochastic multi-period mixed complementarity problems (MCP) for the global natural gas market, as well as solution approaches for large-scale stochastic MCP. The deterministic model is unique in the combination of the level of detail of the actors in the natural gas markets and the transport options, the detailed regional and global coverage, the multi-period approach with endogenous capacity expansions for transportation and storage infrastructure, the seasonal variation in demand and the representation of market power according to Nash-Cournot theory. The model is applied to several scenarios for the natural gas market that cover the formation of a cartel by the members of the Gas Exporting Countries Forum, a low availability of unconventional gas in the United States, and cost reductions in long-distance gas transportation. The results provide insights in how different regions are affected by various developments, in terms of production, consumption, traded volumes, prices and profits of market participants. The stochastic MCP is developed and applied to a global natural gas market problem with four scenarios for a time horizon until 2050 with nineteen regions and containing 78,768 variables. The scenarios vary in the possibility of a gas market cartel formation and varying depletion rates of gas reserves in the major gas importing regions. Outcomes for hedging decisions of market participants show some significant shifts in the timing and location of infrastructure investments, thereby affecting local market situations. A first application of Benders decomposition (BD) is presented to solve a large-scale stochastic MCP for the global gas market with many hundreds of first-stage capacity expansion variables and market players exerting various levels of market power. The largest problem solved successfully using BD contained 47,373 variables of which 763 first-stage variables, however using BD did not result in
Energy Technology Data Exchange (ETDEWEB)
Hollingsworth, Jennifer A. [Los Alamos National Laboratory; Palaniappan, Kumaranand [Los Alamos National Laboratory; Laocharoensuk, Rawiwan [National Science and Technology Center, Thailand; Smith, Nickolaus A. [Los Alamos National Laboratory; Dickerson, Robert M. [Los Alamos National Laboratory; Casson, Joanna L. [Los Alamos National Laboratory; Baldwin, Jon K. [Los Alamos National Laboratory
2012-06-07
Semiconductor nanowires (SC-NWs) have potential applications in diverse technologies from nanoelectronics and photonics to energy harvesting and storage due to their quantum-confined opto-electronic properties coupled with their highly anisotropic shape. Here, we explore new approaches to an important solution-based growth method known as solution-liquid-solid (SLS) growth. In SLS, molecular precursors are reacted in the presence of low-melting metal nanoparticles that serve as molten fluxes to catalyze the growth of the SC-NWs. The mechanism of growth is assumed to be similar to that of vapor-liquid-solid (VLS) growth, with the clear distinctions of being conducted in solution in the presence of coordinating ligands and at relatively lower temperatures (<300 C). The resultant SC-NWs are soluble in common organic solvents and solution processable, offering advantages such as simplified processing, scale-up, ultra-small diameters for quantum-confinement effects, and flexible choice of materials from group III-V to groups II-VI, IV-VI, as well as truly ternary I-III-VI semiconductors as we recently demonstrates. Despite these advantages of SLS growth, VLS offers several clear opportunities not allowed by conventional SLS. Namely, VLS allows sequential addition of precursors for facile synthesis of complex axial heterostructures. In addition, growth proceeds relatively slowly compared to SLS, allowing clear assessments of growth kinetics. In order to retain the materials and processing flexibility afforded by SLS, but add the elements of controlled growth afforded by VLS, we transformed SLS into a flow based method by adapting it to synthesis in a microfluidic system. By this new method - so-called 'flow-SLS' (FSLS) - we have now demonstrated unprecedented fabrication of multi-segmented SC-NWs, e.g., 8-segmented CdSe/ZnSe defined by either compositionally abrupt or alloyed interfaces as a function of growth conditions. In addition, we have studied growth
Rajora, Manik; Zou, Pan; Yang, Yao Guang; Fan, Zhi Wen; Chen, Hung Yi; Wu, Wen Chieh; Li, Beizhi; Liang, Steven Y
2016-01-01
It can be observed from the experimental data of different processes that different process parameter combinations can lead to the same performance indicators, but during the optimization of process parameters, using current techniques, only one of these combinations can be found when a given objective function is specified. The combination of process parameters obtained after optimization may not always be applicable in actual production or may lead to undesired experimental conditions. In this paper, a split-optimization approach is proposed for obtaining multiple solutions in a single-objective process parameter optimization problem. This is accomplished by splitting the original search space into smaller sub-search spaces and using GA in each sub-search space to optimize the process parameters. Two different methods, i.e., cluster centers and hill and valley splitting strategy, were used to split the original search space, and their efficiency was measured against a method in which the original search space is split into equal smaller sub-search spaces. The proposed approach was used to obtain multiple optimal process parameter combinations for electrochemical micro-machining. The result obtained from the case study showed that the cluster centers and hill and valley splitting strategies were more efficient in splitting the original search space than the method in which the original search space is divided into smaller equal sub-search spaces.
A new approach to the solution of the vacuum magnetic problem in fusion machines
Energy Technology Data Exchange (ETDEWEB)
Zabeo, L. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)], E-mail: lzabeo@jet.uk; Artaserse, G. [Association EURATOM-ENEA-CREATE, DIMET Univ. Mediterranea di Reggio Calabria Via Graziella, Loc. Feo di Vito, I-89060 Reggio Calabria (Italy); Cenedese, A. [EURATOM-ENEA Consorzio RFX, C.so Stati Uniti 4, I-35127 Padova (Italy); University of Padova, Department of Management and Engineering, Stradella San Nicola 3, I-36100 Vicenza (Italy); Piccolo, F.; Sartori, F. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)
2007-10-15
The magnetic vacuum topology reconstruction using magnetic measurements is essential in controlling and understanding plasmas produced in magnetic confinement fusion devices. In a wide range of cases, the instruments used to approach the problem have been designed for a specific machine and to solve a specific plasma model. Recently, a new approach has been used for developing new magnetic software called FELIX. The adopted solution in the design allows the use of the software not only at JET but also at other machines. In order to reduce the analysis and debugging time the software has been designed with modularity and platform independence in mind. This results in a large portability and in particular it allows using the same code both offline and in real-time. One of the main aspects of the tool is its capability to solve different plasma models of current distribution. Thanks to this feature, in order to improve the plasma magnetic reconstruction in real-time, a set of different models has been run using FELIX. FELIX is presently running at JET in different real-time analysis and control systems that need vacuum magnetic topology.
Bigdeli, Hadise; Moradi, Morteza; Hajati, Shaaker; Kiani, Mohammad Ali; Toth, Jozsef
2017-10-01
In this work, two different types of Co3O4 nano-crystals were synthesized by (i) conventional direct solid state thermolysis of cobalt terephthalate metal-organic framework (MOF-71) and (ii) new indirect solid state thermolysis of Co(OH)2 derived by alkaline aqueous treatment of MOF-71. The products were then characterized by X-ray diffraction technique (XRD), Fourier transforms infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Reflection electron energy loss spectroscopy (REELS), Brunauer, Emmett, and Teller (BET), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) techniques. By REELS analysis the energy band gap of MOF-71 was determined to be 3.7 eV. Further, electrochemical performance of each Co3O4 nanostructure was studied by the cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) in a three-electrode system in KOH electrolyte. An asymmetric supercapacitor was fabricated using indirect Co3O4 nanoparticles as cathode and electrochemically reduced graphene oxide as anode, and the electrochemical properties were studied and showed a high energy density of 13.51 Wh kg-1 along with a power density of 9775 W kg-1 and good cycling stability with capacitance retention rate of 85% after 2000 cycles.
Energy Technology Data Exchange (ETDEWEB)
Hoshyargar, Vahid; Fadaei, Farzad; Ashrafizadeh, Seyed Nezameddin [Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)
2015-07-15
A comprehensive mathematical model is developed for simulation of ion transport through nanofiltration membranes. The model is based on the Maxwell-Stefan approach and takes into account steric, Donnan, and dielectric effects in the transport of mono and divalent ions. Theoretical ion rejection for multi-electrolyte mixtures was obtained by numerically solving the 'hindered transport' based on the generalized Maxwell-Stefan equation for the flux of ions. A computer simulation has been developed to predict the transport in the range of nanofiltration, a numerical procedure developed linearization and discretization form of the governing equations, and the finite volume method was employed for the numerical solution of equations. The developed numerical method is capable of solving equations for multicomponent systems of n species no matter to what extent the system shows stiffness. The model findings were compared and verified with the experimental data from literature for two systems of Na{sub 2}SO{sub 4}+NaCl and MgCl{sub 2}+NaCl. Comparison showed great agreement for different concentrations. As such, the model is capable of predicting the rejection of different ions at various concentrations. The advantage of such a model is saving costs as a result of minimizing the number of required experiments, while it is closer to a realistic situation since the adsorption of ions has been taken into account. Using this model, the flux of permeates and rejections of multi-component liquid feeds can be calculated as a function of membrane properties. This simulation tool attempts to fill in the gap in methods used for predicting nanofiltration and optimization of the performance of charged nanofilters through generalized Maxwell-Stefan (GMS) approach. The application of the current model may weaken the latter gap, which has arisen due to the complexity of the fundamentals of ion transport processes via this approach, and may further facilitate the industrial
Absorption of hydrogen at the iron-solution interface: FTIR and RT approach
Energy Technology Data Exchange (ETDEWEB)
Carbajal-Castaneda, J.L.
1986-01-01
An investigation of the relation of surface H to that adsorbed in the metal was carried out. The adsorption of thiourea and thiocyanate in solution on iron was also studied. The work carried out included the measurement of the coverage of iron electrodes with H as a function of potential in borate buffer solution, pH = 8.4, in the presence and absence of inhibitors, utilizing a new technique (FTIR); the determination of the hydrogen evolution reaction (HER) with H and D to obtain isotope effect; the determination of adsorption on iron as a function of potential and concentration of thiourea and thiocyanate; the determination of diffusion and solubility of H in Fe at a variety of electrode potentials in ranges relevant to corrosion. Rationalization of the overpotential relation to theta/sub H/ and C/sub H/ was obtained. A plot of C/sub H/ vs theta/sub H/ produces a straight line with slope K which was deduced from a Langmuirian approach. The presence of thiocyanate increased the K value due to a reduction in the rate of hydrogen discharge. It was also found that the majority of H is absorbed on the surface. The increase of hydrogen permeation in the presence of thiourea and thiocyanate is due to the adsorption of these additives on high energy sites leaving the low energy sites for the hydrogen discharge. The adsorption of thiourea fits a Bockris-Swinkels isotherm which represents a water displacement model. Thiourea was found to displace 3 water molecules. Thiocyanate adsorption was found to fit a Bockris-Devanathan-Muller isotherm.
Sonochemical Approach to Synthesis of Co-B Catalysts and Hydrolysis of Alkaline NaBH4 Solutions
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Bilge Coşkuner
2014-01-01
Full Text Available Co-B catalysts are promising candidates for hydrogen evolution via hydrolysis of alkaline sodium borohydride (NaBH4 solutions. In the present paper, a sonochemical approach was investigated for synthesis of Co-B catalysts and hydrolysis of alkaline NaBH4 solutions. Sonochemical application on synthesizing process improved the intrinsic and extrinsic properties of Co-B catalysts such as crystal, spectral, surface area, pore volume, pore diameter, and particle size. Co-B catalysts prepared by sonochemical approach possessed smaller particle size, higher surface area, and higher pore volume than the Co-B catalysts prepared by coprecipitation synthesis. The effects of sonochemical process on hydrolysis of alkaline NaBH4 solutions were investigated by Arrhenius theory. It was clearly demonstrated that the advantages of alkaline NaBH4 solution sonohydrolysis provide superficial effects on hydrogen evolution kinetic as maximum H2 generation rate (HGR and minimum activation energy (Ea.
Fourth-Order Four-Point Boundary Value Problem: A Solutions Funnel Approach
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Panos K. Palamides
2012-01-01
Full Text Available We investigate the existence of positive or a negative solution of several classes of four-point boundary-value problems for fourth-order ordinary differential equations. Although these problems do not always admit a (positive Green's function, the obtained solution is still of definite sign. Furthermore, we prove the existence of an entire continuum of solutions. Our technique relies on the continuum property (connectedness and compactness of the solutions funnel (Kneser's Theorem, combined with the corresponding vector field.
Clark, R. W.; James, R. M.
1981-01-01
A new approach to the solution of matrix equations resulting from integral equations is presented and applied to the solution of two-dimensional Neumann problems describing the inviscid, incompressible flow past an airfoil. The problem is reformulated in terms of a preselected set of mode functions giving an equivalent matrix equation to be solved for the mode-function expansion coefficients. Because of the inherent smoothness of the original problem, the coefficient problem can be solved approximately without significantly affecting the accuracy of the final solution. Very promising two-dimensional results are obtained and the extension of the method to three-dimensional problems is investigated. On the basis of these results it is shown that the computing time for the matrix solution for a large three-dimensional panel method calculation could be reduced by an order of magnitude compared with that required for a direct solution.
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Sergio Raúl Rivera Rodríguez
2004-09-01
Full Text Available The present article reviews the state of the art of optimum capacitor location in distribution systems, provideing guidelines for planners engaged in optimising tension profiles and controlling reagents in distribution networks.Optimising a given solution by exhastive search is studied here; the dimensions of a given problem are determined by evaluating the different possibilities for resolving it and the solution algorithm's computational times and requierements are visualised. An example system (9 node, IEEE is used for illustrating the exhaustive search approach, where it was found that methods used in the literature regarding this topic do not always lead to the optimum solution.
Solution of the nonrelativistic wave equation using the tridiagonal representation approach
Alhaidari, A. D.
2017-07-01
We choose a complete set of square integrable functions as a basis for the expansion of the wavefunction in configuration space such that the matrix representation of the nonrelativistic time-independent linear wave operator is tridiagonal and symmetric. Consequently, the matrix wave equation becomes a symmetric three-term recursion relation for the expansion coefficients of the wavefunction. The recursion relation is then solved exactly in terms of orthogonal polynomials in the energy. Some of these polynomials are not found in the mathematics literature. The asymptotics of these polynomials give the phase shift for the continuous energy scattering states and the spectrum for the discrete energy bound states. Depending on the space and boundary conditions, the basis functions are written in terms of either the Laguerre or Jacobi polynomials. The tridiagonal requirement limits the number of potential functions that yield exact solutions of the wave equation. Nonetheless, the class of exactly solvable problems in this approach is larger than the conventional class (see, for example, Table XII in the text). We also give very accurate results for cases where the wave operator matrix is not tridiagonal but its elements could be evaluated either exactly or numerically with high precision.
Problem Solution Processes of Musicians and Engineers: What do Their Approaches Look Like
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Säde-Pirkko Nissilä
2015-06-01
Full Text Available PBL is learning through becoming conscious of practical and abstract problems and finding ways how to solve them. It can be a pattern which doesn’t follow traditional divisions of disciplines. In this article the material was collected from two, in the first sight, very different groups. One was music students (N = 62 who had to learn to solve various practical and theoretical problems in preparing a program for a series of concerts as collective and individual action. The method used was the 7-step method which divides learning into seven phases proceeding from creating the social frame of reference and mental models (steps 1–4 through actual work (steps 5–6 to the evaluation of the outcomes (step 7. Another group consisted of international, multicultural business leaders in engineering (N = 6. In using earlier the 7-step method, the approaches resembled those of the music students: deepening their professional competences. To engage their ability to use imagination and connect reality with brainstorming and mental flexibility, the creative PBL method 635 was used. Three practical problems were solved so that the solutions included new viewpoints which would be applied to meet the real needs in the near future. The results show that not only were the learning targets of both groups reached but, with reflection included, the processes widened the professional competences of the participants.
New approach to the exact solution of viscous flow due to stretching (shrinking and porous sheet
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Azhar Ali
Full Text Available Exact analytical solutions for the generalized stretching (shrinking of a porous surface, for the variable suction (injection velocity, is presented in this paper. The solution is generalized in the sense that the existing solutions that correspond to various stretching velocities are recovered as a special case of this study. A suitable similarity transformation is introduced to find self-similar solution of the non-linear governing equations. The flow is characterized by a few non-dimensional parameters signifying the problem completely. These parameters are such that the whole range of stretching (shrinking problems discussed earlier can be recovered by assigning appropriate values to these parameters. A key point of the whole narrative is that a number of earlier works can be abridged into one generalized problem through the introduction of a new similarity transformation and finding its exact solution encompassing all the earlier solutions. Keywords: Exact solutions, New similarities, Permeable and moving sheet
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Zhi-Feng Yao
2016-01-01
Full Text Available The turbulent flow in a centrifugal pump impeller is bounded by complex surfaces, including blades, a hub and a shroud. The primary challenge of the flow simulation arises from the generation of a boundary layer between the surface of the impeller and the moving fluid. The principal objective is to evaluate the near-wall solution approaches that are typically used to deal with the flow in the boundary layer for the large-eddy simulation (LES of a centrifugal pump impeller. Three near-wall solution approaches –the wall-function approach, the wall-resolved approach and the hybrid Reynolds averaged Navier–Stoke (RANS and LES approach – are tested. The simulation results are compared with experimental results conducted through particle imaging velocimetry (PIV and laser Doppler velocimetry (LDV. It is found that the wall-function approach is more sparing of computational resources, while the other two approaches have the important advantage of providing highly accurate boundary layer flow prediction. The hybrid RANS/LES approach is suitable for predicting steady-flow features, such as time-averaged velocities and hydraulic losses. Despite the fact that the wall-resolved approach is expensive in terms of computing resources, it exhibits a strong ability to capture a small-scale vortex and predict instantaneous velocity in the near-wall region in the impeller. The wall-resolved approach is thus recommended for the transient simulation of flows in centrifugal pump impellers.
Wang, Yifeng; Xu, Huifang
2001-05-01
Trace metal partitioning between authigenic minerals and aqueous solutions is of great interest to both geochemical and environmental communities. In this paper, we have developed a linear free energy correlation model that correlates metal partition coefficients with metal cation properties: -2.303 RT log Kd + ΔG f,MZ+0 = a∗MHXΔ Gn,MZ+0 + β ∗MHXrMZ+ + b∗MHX where a∗MHX, β ∗MHX, and b∗MHX are constants, which can be determined by a regression analysis. For isovalent metal partitioning, because of the constraint of Kd = 1 for the host metal, this correlation can be also expressed as: -2.303 RT log Kd = a∗MHX(Δ Gn,MHZ+0 - Δ Gn,M0) + β ∗MHX( rMZ+ - rn,MHZ+) - (Δ Gf,MZ+0 - Δ G0f,MHZ+). Host minerals from an isostructural family have the same linear free energy relationship, as long as the relationship is expressed as a function of the differences in cation properties between substituent and host metals. We have applied our model to both isovalent and non-isovalent metal partitioning in carbonate minerals. The model closely fits experimental data, demonstrating the robustness of the proposed linear free energy relationship. Using the model, we have predicted the partition coefficients of divalent and trivalent metals between various carbonate minerals and aqueous solutions. The differences between the predicted and experimental values are generally less than 1 logarithmic unit for divalent cations and less than 0.4 logarithmic unit for trivalent cations. Magnesite is predicted to have the largest partition coefficients among the carbonate minerals with a calcite structure and therefore, can be a good scavenger for toxic metals. The kinetic effect on metal partitioning can be described graphically by a "seesaw" line anchored at a host cation. To explain the rate dependence of partition coefficients, we have proposed a conceptual model that relates metal partitioning to surface adsorption. The conceptual model suggests that as the rate of host
NASA Water-Cycle Solutions Networks and Community of Practice Approaches to enhance Decision-making
Pozzi, W.; Ward, J.; Cox, E. L.; Lawford, R. G.; Matthews, D.; Houser, P.; Doherty, M.
2009-12-01
The Japanese Aerospace Exploration Agency (JAXA) has created the Asian Water Cycle Initiative regional network for South Asia and NASA has launched two networks to enhance the rapid transitioning of scientific achievements and NASA technology into operational use. All three networks meet a new type of scientific challenge by providing strong linkage among the scientific communities, the space agencies, and decision makers. We focus here on the two NASA-sponsored networks that carry out complementary approaches: WaterNet focused on large-scale national/international collaborations; North Olympic Peninsula Solution Network developed a local proof of concept project first, then began integration and collaboration at progressively larger scales, culminating with a national-level discourse via the National Association of Resource, Conservation and Development councils (NARC&DC). The ultimate goals of both groups were to bring NASA Science and Technology products to organizations/groups to improve decision making and to create collaborations and networks that would extend beyond the parent groups and expand and continue to be sustainable, after the original projects were completed. This paper provides a summary of lessons learned. The primary objective of the NOPSN is to bring NASA science and technology tools to watershed managers to improve the scientific basis of decision making in NASA national application areas of water management, agricultural efficiency, and ecological forecasting. To achieve this objective, the NOPSN team first developed and implemented a local proof-of-concept project for the Dungeness River, Washington, to improve water forecasting. The team then developed local and regional collaborations with water resource managers, stakeholder groups, and local, state, and federal agencies to identify environmental issues, challenges, and needs that could be addressed with NASA technology. Finally,through its partnership with NARC&D, it provided the NOPSN
Gordon, Christopher P
2018-01-03
Within a decade of Merrifield's seminal description of solid-phase peptide synthesis, the synergies between solid-phase approaches and flow synthesis were noted by a number of groups. However, despite the various advantages flow brings to peptide synthesis, throughout the 1990s and 2000s, interest in the technique was overshadowed by microwave assisted approaches. However, the current expansion of flow technologies has reinvigorated interest in both solid-phase and solution-phase continuous-flow approaches for assembling peptides. This perspective traces the introduction and evolution of continuous-flow solid-phase synthesis from a practical aspect with a particular focus on solid supports, acylation protocols, and racemisation suppression. Practical aspects of solution-phase continuous-flow peptide synthesis are also considered with an evaluation of microreactor systems, coupling protocols, and fragment-based approaches for assembly of extended peptide units.
A transformed path integral approach for solution of the Fokker-Planck equation
Subramaniam, Gnana M.; Vedula, Prakash
2017-10-01
A novel path integral (PI) based method for solution of the Fokker-Planck equation is presented. The proposed method, termed the transformed path integral (TPI) method, utilizes a new formulation for the underlying short-time propagator to perform the evolution of the probability density function (PDF) in a transformed computational domain where a more accurate representation of the PDF can be ensured. The new formulation, based on a dynamic transformation of the original state space with the statistics of the PDF as parameters, preserves the non-negativity of the PDF and incorporates short-time properties of the underlying stochastic process. New update equations for the state PDF in a transformed space and the parameters of the transformation (including mean and covariance) that better accommodate nonlinearities in drift and non-Gaussian behavior in distributions are proposed (based on properties of the SDE). Owing to the choice of transformation considered, the proposed method maps a fixed grid in transformed space to a dynamically adaptive grid in the original state space. The TPI method, in contrast to conventional methods such as Monte Carlo simulations and fixed grid approaches, is able to better represent the distributions (especially the tail information) and better address challenges in processes with large diffusion, large drift and large concentration of PDF. Additionally, in the proposed TPI method, error bounds on the probability in the computational domain can be obtained using the Chebyshev's inequality. The benefits of the TPI method over conventional methods are illustrated through simulations of linear and nonlinear drift processes in one-dimensional and multidimensional state spaces. The effects of spatial and temporal grid resolutions as well as that of the diffusion coefficient on the error in the PDF are also characterized.
Solution based approaches for the morphology control of BaTiO3 particulates
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Florentina Maxim
2010-09-01
Full Text Available Within the action COST 539 - ELENA our contribution was aimed at studying solution based approaches for the morphology control of BaTiO3 particulates. Initially, our kinetic analysis and systematic structural and morphological studies, demonstrated that during hydrothermal synthesis from layered titanate nanotubes (TiNTS, BaTiO3 forms via two mechanisms depending on the temperature and time. At low temperatures (90°C, “wild” type BaTiO3 dendritic particles with cubic structure were formed through a phase boundary topotactic reaction. At higher temperatures and/or for longer times time, the reaction is controlled by a dissolution precipitation mechanism and “seaweed” type BaTiO3 dendrites are formed. Our results unambiguously elucidated why TiNTs do not routinely act as templates for the formation of 1D BaTiO3.In our subsequent investigations, the effect of additives on the aqueous and hydrothermal synthesis of BaTiO3 was assessed. We reported that although the tested additives influenced the growth of BaTiO3, their behaviour varied; poly(acrylic acid (PAA adsorbed on specific crystallographic faces changing the growth kinetics and inducing the oriented attachment of the particles; poly(vinyl pyrrolidone (PVP, sodium dodecylsulfate (SDS and hydroxypropylmethylcellulose (HPMC act as growth inhibitors rather than crystal habit modifiers; and DFructose appeared to increase the activation energy for nucleation, resulting in small crystals (26 nm. Our work clearly indicates that the synthesis of 1D nanostructures of complex oxides by chemical methods is non trivial.
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Ishak Altun
2016-01-01
Full Text Available We provide sufficient conditions for the existence of a unique common fixed point for a pair of mappings T,S:X→X, where X is a nonempty set endowed with a certain metric. Moreover, a numerical algorithm is presented in order to approximate such solution. Our approach is different to the usual used methods in the literature.
Solution immersed silicon (SIS)-based biosensors: a new approach in biosensing.
Diware, M S; Cho, H M; Chegal, W; Cho, Y J; Jo, J H; O, S W; Paek, S H; Yoon, Y H; Kim, D
2015-02-07
A novel, solution immersed silicon (SIS)-based sensor has been developed which employs the non-reflecting condition (NRC) for a p-polarized wave. The SIS sensor's response is almost independent of change in the refractive index (RI) of a buffer solution (BS) which makes it capable of measuring low-concentration and/or low-molecular-weight compounds.
Tisdell, C. C.
2017-01-01
Solution methods to exact differential equations via integrating factors have a rich history dating back to Euler (1740) and the ideas enjoy applications to thermodynamics and electromagnetism. Recently, Azevedo and Valentino presented an analysis of the generalized Bernoulli equation, constructing a general solution by linearizing the problem…
A solution for exterior and relative orientation in photogrammetry, a genetic evolution approach
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Elgasim Elamin Elnima
2015-01-01
In this paper, we present a solution for the determination of the exterior orientation parameters (space resection based on genetic evolution algorithms. This optimization model for space resection can be implemented with or without redundancy and requires no linearization. The proposed model is simple and converges to the global optimal solution.
In the Case of a Depressed Woman: Solution-Focused or Narrative Therapy Approaches?
Andrews, Jennifer; Clark, David
1996-01-01
Using a case example, provides an overview of postmodern therapies in family counseling. Focuses on solution-focused therapy and narrative therapy; presents an example of a solution-focused interview and a narrative interview. Emphasizes that different views lead to different therapeutic goals and practices. (RJM)
Sahu, Omprakash
2017-10-01
The sugar cane industry is one of the most water demanding industries. Sugar industries consume and generate excess amount of water. The generated water contains organic compounds, which would cause pollution. The aim of this research work is to study the effectiveness of metal compound for treatment of sugar industry waste water by thermolysis and electrolysis process. The result shows ferrous metal catalyst shows 80 and 85 % chemical oxygen demand and color removal at pH 6, optimum mass loading 4 kg/m3, treatment temperature 85 °C and treatment time 9 h. When ferrous material was used as electrode, maximum 81 % chemical oxygen demand and 84 % color removal at pH 6, current density 156 Am-2, treatment time 120 min and anode consumption 0.7 g for 1.5 L wastewater were obtained.
Tapsanit, Piyawath; Yamashita, Masatsugu; Otani, Chiko
2014-01-13
The analytical solutions of the electromagnetic waves in the inhomogeneous cylindrical hyperlens (CH) comprising concentric cylindrical layers (CCLs) with multiple point sources located either outside the structure in the focusing process or inside the core in the magnifying process are obtained by means of Green's function analysis. The solutions are consistent with FDTD simulation in both processes. The sub-wavelength focal spot λ/16.26 from two point sources with wavelength 465 nm is demonstrated in the CH made by alternating silver and silica CCLs. Our solutions are expected to be the efficient tools for designing the sub-wavelength focusing and imaging cylindrical hyperlens.
Sparse Solutions for Single Class SVMs: A Bi-Criterion Approach
National Aeronautics and Space Administration — In this paper we propose an innovative learning algorithm - a variation of One-class Support Vector Machines (SVMs) learning algorithm to produce sparser solutions...
Osmotic and diffusio-osmotic flow generation at high solute concentration. I. Mechanical approaches.
Marbach, Sophie; Yoshida, Hiroaki; Bocquet, Lydéric
2017-05-21
In this paper, we explore various forms of osmotic transport in the regime of high solute concentration. We consider both the osmosis across membranes and diffusio-osmosis at solid interfaces, driven by solute concentration gradients. We follow a mechanical point of view of osmotic transport, which allows us to gain much insight into the local mechanical balance underlying osmosis. We demonstrate in particular how the general expression of the osmotic pressure for mixtures, as obtained classically from the thermodynamic framework, emerges from the mechanical balance controlling non-equilibrium transport under solute gradients. Expressions for the rejection coefficient of osmosis and the diffusio-osmotic mobilities are accordingly obtained. These results generalize existing ones in the dilute solute regime to mixtures with arbitrary concentrations.
Operational matrix approach for approximate solution of fractional model of Bloch equation
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Harendra Singh
2017-04-01
Full Text Available In present paper operational matrix of integration for Laguerre polynomial is used to solve fractional model of Bloch equation in nuclear magnetic resonance (NMR. The operational matrix converts the Bloch equation in a system of linear algebraic equations. Solving system we obtain the approximate solutions for fractional Bloch equation. Results are compared with existing methods and exact solution. Graphs are plotted for different fractional values of time derivatives.
A thermodynamic approach to assess organic solute adsorption onto activated carbon in water
De Ridder, David J.
2012-08-01
In this paper, the hydrophobicity of 13 activated carbons is determined by various methods; water vapour adsorption, immersion calorimetry, and contact angle measurements. The quantity and type of oxygen-containing groups on the activated carbon were measured and related to the methods used to measure hydrophobicity. It was found that the water-activated carbon adsorption strength (based on immersion calorimetry, contact angles) depended on both type and quantity of oxygen-containing groups, while water vapour adsorption depended only on their quantity. Activated carbon hydrophobicity measurements alone could not be related to 1-hexanol and 1,3-dichloropropene adsorption. However, a relationship was found between work of adhesion and adsorption of these solutes. The work of adhesion depends not only on activated carbon-water interaction (carbon hydrophobicity), but also on solute-water (solute hydrophobicity) and activated carbon-solute interactions. Our research shows that the work of adhesion can explain solute adsorption and includes the effect of hydrogen bond formation between solute and activated carbon. © 2012 Elsevier Ltd. All rights reserved.
Saltas, V.; Horlait, D.; Sgourou, E. N.; Vallianatos, F.; Chroneos, A.
2017-12-01
Modelling solid solutions is fundamental in understanding the properties of numerous materials which are important for a range of applications in various fields including nanoelectronics and energy materials such as fuel cells, nuclear materials, and batteries, as the systematic understanding throughout the composition range of solid solutions for a range of conditions can be challenging from an experimental viewpoint. The main motivation of this review is to contribute to the discussion in the community of the applicability of methods that constitute the investigation of solid solutions computationally tractable. This is important as computational modelling is required to calculate numerous defect properties and to act synergistically with experiment to understand these materials. This review will examine in detail two examples: silicon germanium alloys and MAX phase solid solutions. Silicon germanium alloys are technologically important in nanoelectronic devices and are also relevant considering the recent advances in ternary and quaternary groups IV and III-V semiconductor alloys. MAX phase solid solutions display a palette of ceramic and metallic properties and it is anticipated that via their tuning they can have applications ranging from nuclear to aerospace industries as well as being precursors for particular MXenes. In the final part, a brief summary assesses the limitations and possibilities of the methodologies discussed, whereas there is discussion on the future directions and examples of solid solution systems that should prove fruitful to consider.
An efficient and practical approach to obtain a better optimum solution for structural optimization
Chen, Ting-Yu; Huang, Jyun-Hao
2013-08-01
For many structural optimization problems, it is hard or even impossible to find the global optimum solution owing to unaffordable computational cost. An alternative and practical way of thinking is thus proposed in this research to obtain an optimum design which may not be global but is better than most local optimum solutions that can be found by gradient-based search methods. The way to reach this goal is to find a smaller search space for gradient-based search methods. It is found in this research that data mining can accomplish this goal easily. The activities of classification, association and clustering in data mining are employed to reduce the original design space. For unconstrained optimization problems, the data mining activities are used to find a smaller search region which contains the global or better local solutions. For constrained optimization problems, it is used to find the feasible region or the feasible region with better objective values. Numerical examples show that the optimum solutions found in the reduced design space by sequential quadratic programming (SQP) are indeed much better than those found by SQP in the original design space. The optimum solutions found in a reduced space by SQP sometimes are even better than the solution found using a hybrid global search method with approximate structural analyses.
A new geoid solution for South America - Comparing new and established approaches
Marchenko, D.; Blitzkow, D.; Meyer, U.
2003-04-01
During the last ten years the land gravity database on South America has been largely enriched with new gravity surveys in different countries of the continent. After testing different compilations, also the offshore data was expanded using the KMS'99 2'x2' gravity anomalies (Andersen &Knudsen, 1998) derived from satellite altimetry. On this base, the so far existing 5'x5' mean gravity anomaly data file for South America of the Polytechnic School in Sao Paulo, limited by 25° N to 60° S in latitude and 25° W to 100° W in longitude, was updated. This contribution intends to present the results of geoid computations for the described area and data using FFT, direct numerical integration of Stokes's formula and sequential multipole analysis in comparison. The software used for FFT has different alternatives, 1D-FFT and 2D-FFT with special kernel modifications. Both options were tested, in a version of the software provided by W. Featherstone and M. Sideris (Sideris, 1998). The second alternative is a straightforward numerical integration of Stokes's integral using the kernel modification originally presented by Vanicek &Kleusberg (Vanicek, 1987). The third one is the sequential multipole analysis approach (Marchenko et al., 2001). In this new approach, the residual gravity field was derived by applying the terrain correction to the 10'x10' free-air gravity anomalies and reducing of the EGM'96 (n=360) global gravity model. The direct approximation of residual gravity anomalies (adopted in this study as Faye anomalies) by means of radial multipoles potentials of different degrees was made for the construction of the corresponding preliminary model (of the gravimetric geoid only). On the next step this model was used for the re-adjustment of the multipole moments based on the following set of heterogeneous data: Faye gravity anomalies over the land and KMS-SSH (interpolated at the same grid mean Sea Surface Heights) over the ocean (gravimetry / altimetry solution
Olofsson, Jessica; Pihl, Johan; Sinclair, Jon; Sahlin, Eskil; Karlsson, Mattias; Orwar, Owe
2004-09-01
We report on a microfluidic device that generates separate solution environments in macroscopic volumes. Spatially distinct patterns are created by emitting fluids from 16 different sources (closely spaced microchannels) into a solution-filled macroscopic chamber. The fluid in neighboring microchannels couples viscously in the macroscopic container, generating one single interdigitated stream. Scanning nanoelectrode amperometry was used for characterizing the concentration landscape and the diffusion zones between solutions running in parallel at different coordinates in the stream. These experiments were complemented by finite element simulations of the Navier-Stokes and mass transport equations to describe the velocity distributions and the diffusion behavior. For in channel flow velocities of 50 mm.s(-1), patterns could persist on the order of millimeters to centimeters in the open volume. The most narrow diffusion zones with widths less than 10 microm (5-95% concentration change) were found some tens of micrometers out in the macroscopic container. We demonstrate that a 14-microm-diameter nearly spherical object (biological cell) attached to a micropipet can be moved from one solution environment to another by a lateral displacement of only 8 microm. The device is suitable for applications where the solution environment around a microscopic or nanoscopic sensor needs to be changed multiple times, i.e., in order to build layered structures, for obtaining binding isotherms, and kinetic information, for example, on ion channels, enzymes, and receptors as well as in applications where different loci on an object need to be exposed to different environments or where complex solution environments need to be created for studies of interfacial chemistry between two streaming layers. Copyright 2004 American Chemical Society
A minimum wage solution to halving world poverty by 2015: A stakeholder approach
Directory of Open Access Journals (Sweden)
Arvind Ashta
2013-03-01
Full Text Available The UNDP has set Millennium Goals which include the halving of world poverty by 2015. This was translated into reducing by half the number of people living in abject poverty. We examine some existing poverty reduction solutions which are being experimented with, including aid (with central planning with participatory development, property rights, education, microfinance, bottom of the pyramid inclusion, and public sector employment, and find that these have been inadequate to the task, even conjointly. We add a minimum wage based solution.
A Comparative Approach to the Solution of the Zabolotskaya-Khokhlov Equation by Iteration Methods
Directory of Open Access Journals (Sweden)
Saeed Ahmed
2016-01-01
Full Text Available We employed different iteration methods like Homotopy Analysis Method (HAM, Adomian Decomposition Method (ADM, and Variational Iteration Method (VIM to find the approximate solution to the Zabolotskaya-Khokhlov (ZK equation. Iteration methods are used to solve linear and nonlinear PDEs whose classical methods are either very complex or too limited to apply. A comparison study has been made to see which of these methods converges to the approximate solution rapidly. The result revealed that, amongst these methods, ADM is more effective and simpler tool in its nature which does not require any transformation or linearization.
Zheng, Youqi; Choi, Sooyoung; Lee, Deokjung
2017-12-01
A new approach based on the method of characteristics (MOC) is proposed to solve the neutron transport equation. A new three-dimensional (3D) spatial discretization is applied to avoid the instability issue of the transverse leakage iteration of the traditional 2D/1D approach. In this new approach, the axial and radial variables are discretized in two different ways: the linear expansion is performed in the axial direction, then, the 3D solution of the angular flux is transformed to be the planar solution of 2D angular expansion moments, which are solved by the planar MOC sweeping. Based on the boundary and interface continuity conditions, the 2D expansion moment solution is equivalently transformed to be the solution of the axially averaged angular flux. Using the piecewise averaged angular flux at the top and bottom surfaces of 3D meshes, the planes are coupled to give the 3D angular flux distribution. The 3D CMFD linear system is established from the surface net current of every 3D pin-mesh to accelerate the convergence of power iteration. The STREAM code is extended to be capable of handling 3D problems based on the new approach. Several benchmarks are tested to verify its feasibility and accuracy, including the 3D homogeneous benchmarks and heterogeneous benchmarks. The computational sensitivity is discussed. The results show good accuracy in all tests. With the CMFD acceleration, the convergence is stable. In addition, a pin-cell problem with void gap is calculated. This shows the advantage compared to the traditional 2D/1D MOC methods.
Iszatt-White, Marian
2011-01-01
The view of context as something which restricts the range of research but is not an integral part of that which is being researched is implicit in many traditional approaches to leadership theory development. Some recent approaches have sought to address this by taking a more directly situated approach to the understanding of leadership, and by paying close attention to the practical accomplishment of leadership work within a given context. It is the premise of this paper, however, that ther...
Directory of Open Access Journals (Sweden)
Md. Nur Alam
2014-03-01
Full Text Available The new approach of generalized (G′/G-expansion method is significant, powerful and straightforward mathematical tool for finding exact traveling wave solutions of nonlinear evolution equations (NLEEs arise in the field of engineering, applied mathematics and physics. Dispersive effects due to microstructure of materials combined with nonlinearities give rise to solitary waves. In this article, the new approach of generalized (G′/G-expansion method has been applied to construct general traveling wave solutions of the strain wave equation in microstructured solids. Abundant exact traveling wave solutions including solitons, kink, periodic and rational solutions have been found. These solutions might play important role in engineering fields.
A Predictor-Corrector Approach for the Numerical Solution of Fractional Differential Equations
Diethelm, Kai; Ford, Neville J.; Freed, Alan D.; Gray, Hugh R. (Technical Monitor)
2002-01-01
We discuss an Adams-type predictor-corrector method for the numerical solution of fractional differential equations. The method may be used both for linear and for nonlinear problems, and it may be extended to multi-term equations (involving more than one differential operator) too.
An Agent Based Modelling Approach for Multi-Stakeholder Analysis of City Logistics Solutions
Anand, N.
2015-01-01
This thesis presents a comprehensive framework for multi-stakeholder analysis of city logistics solutions using agent based modeling. The framework describes different stages for the systematic development of an agent based model for the city logistics domain. The framework includes a
Category Theory Approach to Solution Searching Based on Photoexcitation Transfer Dynamics
Directory of Open Access Journals (Sweden)
Makoto Naruse
2017-07-01
Full Text Available Solution searching that accompanies combinatorial explosion is one of the most important issues in the age of artificial intelligence. Natural intelligence, which exploits natural processes for intelligent functions, is expected to help resolve or alleviate the difficulties of conventional computing paradigms and technologies. In fact, we have shown that a single-celled organism such as an amoeba can solve constraint satisfaction problems and related optimization problems as well as demonstrate experimental systems based on non-organic systems such as optical energy transfer involving near-field interactions. However, the fundamental mechanisms and limitations behind solution searching based on natural processes have not yet been understood. Herein, we present a theoretical background of solution searching based on optical excitation transfer from a category-theoretic standpoint. One important indication inspired by the category theory is that the satisfaction of short exact sequences is critical for an adequate computational operation that determines the flow of time for the system and is termed as “short-exact-sequence-based time.” In addition, the octahedral and braid structures known in triangulated categories provide a clear understanding of the underlying mechanisms, including a quantitative indication of the difficulties of obtaining solutions based on homology dimension. This study contributes to providing a fundamental background of natural intelligence.
A solution approach to the ROADEF/EURO 2010 challenge based on Benders' Decomposition
DEFF Research Database (Denmark)
Lusby, Richard Martin; Muller, Laurent Flindt; Petersen, Bjørn
them satisfy the constraints not part of the mixed integer program. A number of experiments are performed on the available benchmark instances. These experiments show that the approach is competitive on the smaller instances, but not for the larger ones. We believe the exact approach gives insight...
Suzuoka, Daiki; Takahashi, Hideaki; Morita, Akihiro
2014-04-07
We developed a perturbation approach to compute solvation free energy Δμ within the framework of QM (quantum mechanical)/MM (molecular mechanical) method combined with a theory of energy representation (QM/MM-ER). The energy shift η of the whole system due to the electronic polarization of the solute is evaluated using the second-order perturbation theory (PT2), where the electric field formed by surrounding solvent molecules is treated as the perturbation to the electronic Hamiltonian of the isolated solute. The point of our approach is that the energy shift η, thus obtained, is to be adopted for a novel energy coordinate of the distribution functions which serve as fundamental variables in the free energy functional developed in our previous work. The most time-consuming part in the QM/MM-ER simulation can be, thus, avoided without serious loss of accuracy. For our benchmark set of molecules, it is demonstrated that the PT2 approach coupled with QM/MM-ER gives hydration free energies in excellent agreements with those given by the conventional method utilizing the Kohn-Sham SCF procedure except for a few molecules in the benchmark set. A variant of the approach is also proposed to deal with such difficulties associated with the problematic systems. The present approach is also advantageous to parallel implementations. We examined the parallel efficiency of our PT2 code on multi-core processors and found that the speedup increases almost linearly with respect to the number of cores. Thus, it was demonstrated that QM/MM-ER coupled with PT2 deserves practical applications to systems of interest.
Villaire, Michael; Gonzalez, Diana Peña; Johnson, Kirby L
2017-01-01
This chapter discusses the need for innovative health literacy solutions to combat extensive chronic disease prevalence and costs. The authors explore the intersection of chronic disease management and health literacy. They provide specific examples of successful health literacy interventions for managing several highly prevalent chronic diseases. This is followed by suggestions on pairing research and practice to support effective disease management programs. In addition, the authors discuss strategies for collection and dissemination of knowledge gained from collaborations between researchers and practitioners. They identify current challenges specific to disseminating information from the health literacy field and offer potential solutions. The chapter concludes with a brief look at future directions and organizational opportunities to integrate health literacy practices to address the need for effective chronic disease management.
Comparative analysis of analytical solutions for F2P(x ,t ) in the DGLAP approach
Choudhury, D. K.; Borah, Neelakshi N. K.
2017-01-01
Coupled Dokshitzer-Gribov-Lipatov-Altarelli-Parisi equations involving singlet quark and gluon distributions are explored by a Taylor expansion at small x as two first-order partial differential equations in two variables: Bjorken x and t (t =l n Q/2Λ2). The system of equations are then solved by Lagrange's method and the method of characteristics. We obtain the proton structure function F2P(x ,t ) by combining the corresponding nonsinglet and singlet structure functions with both methods. Analytical solutions for F2P(x ,t ) thus obtained are compared with the recent data published by the H1 and ZEUS Collaborations as well as with NNPDF3.0 parametrization, and their compatibility is checked. Comparative analysis favors the analytical solution by Lagrange's method; the plausible reasons behind that are also discussed.
Solution of a nonlinear time-delay model in biology via semi-analytical approaches
Dehghan, Mehdi; Salehi, Rezvan
2010-07-01
The delay logistic equations have been extensively used as models in biology and other sciences, with particular emphasis on population dynamics. In this work, the variational iteration and Adomian decomposition methods are applied to solve the delay logistic equation. The variational iteration method is based on the incorporation of a general Lagrange multiplier in the construction of correction functional for the equation. On the other hand, the Adomian decomposition method approximates the solution as an infinite series and usually converges to the accurate solution. Moreover, these techniques reduce the volume of calculations because they have no need of discretization of the variables, linearization or small perturbations. Illustrative examples are included to demonstrate the validity and applicability of the presented methods.
A new approach to the exact solutions of the effective mass Schrodinger equation
Tezcan, Cevdet; Sever, Ramazan; Yesiltas, Ozlem
2007-01-01
Effective mass Schrodinger equation is solved exactly for a given potential. Nikiforov-Uvarov method is used to obtain energy eigenvalues and the corresponding wave functions. A free parameter is used in the transformation of the wave function. The effective mass Schrodinger equation is also solved for the Morse potential transforming to the constant mass Schr\\"{o}dinger equation for a potential. One can also get solution of the effective mass Schrodinger equation starting from the constant m...
Low-cost Approaches for Flux-pinning Enhancements in YBCO Films Using Solution Processing
Energy Technology Data Exchange (ETDEWEB)
Sathyamurthy, Srivatsan [ORNL; Leonard, Keith J [ORNL; Bhuiyan, Md S [ORNL; Aytug, Tolga [ORNL; Kang, Sukill [ORNL; Martin, Patrick M [ORNL; Hunt, Rodney Dale [ORNL; Paranthaman, Mariappan Parans [ORNL
2007-01-01
Nanoparticles of several oxides have been synthesized using reverse micelle process. Microemulsions containing n-octane as the oil phase, cetyl trimethylammonium bromide and 1-butanol as surfactants, and an aqueous solution of metal nitrates and sodium hydroxide were used as the reaction medium. The nanoparticles obtained were characterized using differential thermal analysis, x-ray diffraction, and transmission electron microscopy. The application of these particles for flux-pinning enhancements has been studied.
Numerical Solution of Incompressible Navier-Stokes Equations Using a Fractional-Step Approach
Kiris, Cetin; Kwak, Dochan
1999-01-01
A fractional step method for the solution of steady and unsteady incompressible Navier-Stokes equations is outlined. The method is based on a finite volume formulation and uses the pressure in the cell center and the mass fluxes across the faces of each cell as dependent variables. Implicit treatment of convective and viscous terms in the momentum equations enables the numerical stability restrictions to be relaxed. The linearization error in the implicit solution of momentum equations is reduced by using three subiterations in order to achieve second order temporal accuracy for time-accurate calculations. In spatial discretizations of the momentum equations, a high-order (3rd and 5th) flux-difference splitting for the convective terms and a second-order central difference for the viscous terms are used. The resulting algebraic equations are solved with a line-relaxation scheme which allows the use of large time step. A four color ZEBRA scheme is employed after the line-relaxation procedure in the solution of the Poisson equation for pressure. This procedure is applied to a Couette flow problem using a distorted computational grid to show that the method minimizes grid effects. Additional benchmark cases include the unsteady laminar flow over a circular cylinder for Reynolds Numbers of 200, and a 3-D, steady, turbulent wingtip vortex wake propagation study. The solution algorithm does a very good job in resolving the vortex core when 5th-order upwind differencing and a modified production term in the Baldwin-Barth one-equation turbulence model are used with adequate grid resolution.
A new approach to exact solutions construction in scalar cosmology with a Gauss-Bonnet term
Fomin, I. V.; Chervon, S. V.
2017-08-01
We study the cosmological model based on Einstein-Gauss-Bonnet gravity with non-minimal coupling of a scalar field to a Gauss-Bonnet term in four-dimensional (4D) Friedmann universe. We show how constructing the exact solutions by the method based on a confrontation of the Hubble parameter in the model under consideration is achieved with that in a standard scalar field inflationary cosmology.
Energy Technology Data Exchange (ETDEWEB)
Puthirath, Anand B.; Varma, Sreekanth J.; Jayalekshmi, S., E-mail: jayalekshmi@cusat.ac.in [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Cochin, Kerala 682022 (India); Methattel Raman, Shijeesh [Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics, Cochin University of Science and Technology, Cochin, Kerala 682022 (India)
2016-04-18
Emeraldine salt form of polyaniline (PANI) was synthesized by chemical oxidative polymerisation method using ammonium persulfate as oxidant. Resultant emeraldine salt form of PANI was dedoped using ammonia solution and then re-doped with camphor sulphonic acid (CSA), naphthaline sulphonic acid (NSA), hydrochloric acid (HCl), and m-cresol. Thin films of these doped PANI samples were deposited on glass substrates using solution casting method with m-cresol as solvent. A level surface was employed to get homogeneous thin films of uniform thickness. Detailed X-ray diffraction studies have shown that the films are exceptionally crystalline. The crystalline peaks observed in the XRD spectra can be indexed to simple monoclinic structure. FTIR and Raman spectroscopy studies provide convincing explanation for the exceptional crystallinity observed in these polymer films. FESEM and AFM images give better details of surface morphology of doped PANI films. The DC electrical conductivity of the samples was measured using four point probe technique. It is seen that the samples also exhibit quite high DC electrical conductivity, about 287 S/cm for CSA doped PANI, 67 S/cm for NSA doped PANI 65 S/cm for HCl doped PANI, and just below 1 S/cm for m-cresol doped PANI. Effect of using the level surface for solution casting is studied and correlated with the observed crystallinity.
A new approach for solution of vehicle routing problem with hard ...
Indian Academy of Sciences (India)
SERAP ERCAN CжMERT
2017-11-27
-medoids clustering algorithm; DBSCAN clustering algorithm; cluster first route second approach. 1. Introduction. Vehicle routing .... that allowed multiple trips of vehi- cles. The methods based on branch-and-price consisted of.
Hajrahimi, Nafiseh; Dehaghani, Sayed Mehdi Hejazi; Hajrahimi, Nargess; Sarmadi, Sima
2014-01-01
Implementing information technology in the best possible way can bring many advantages such as applying electronic services and facilitating tasks. Therefore, assessment of service providing systems is a way to improve the quality and elevate these systems including e-commerce, e-government, e-banking, and e-learning. This study was aimed to evaluate the electronic services in the website of Isfahan University of Medical Sciences in order to propose solutions to improve them. Furthermore, we aim to rank the solutions based on the factors that enhance the quality of electronic services by using analytic hierarchy process (AHP) method. Non-parametric test was used to assess the quality of electronic services. The assessment of propositions was based on Aqual model and they were prioritized using AHP approach. The AHP approach was used because it directly applies experts' deductions in the model, and lead to more objective results in the analysis and prioritizing the risks. After evaluating the quality of the electronic services, a multi-criteria decision making frame-work was used to prioritize the proposed solutions. Non-parametric tests and AHP approach using Expert Choice software. The results showed that students were satisfied in most of the indicators. Only a few indicators received low satisfaction from students including, design attractiveness, the amount of explanation and details of information, honesty and responsiveness of authorities, and the role of e-services in the user's relationship with university. After interviewing with Information and Communications Technology (ICT) experts at the university, measurement criteria, and solutions to improve the quality were collected. The best solutions were selected by EC software. According to the results, the solution "controlling and improving the process in handling users complaints" is of the utmost importance and authorities have to have it on the website and place great importance on updating this process
Hajrahimi, Nafiseh; Dehaghani, Sayed Mehdi Hejazi; Hajrahimi, Nargess; Sarmadi, Sima
2014-01-01
Context: Implementing information technology in the best possible way can bring many advantages such as applying electronic services and facilitating tasks. Therefore, assessment of service providing systems is a way to improve the quality and elevate these systems including e-commerce, e-government, e-banking, and e-learning. Aims: This study was aimed to evaluate the electronic services in the website of Isfahan University of Medical Sciences in order to propose solutions to improve them. Furthermore, we aim to rank the solutions based on the factors that enhance the quality of electronic services by using analytic hierarchy process (AHP) method. Materials and Methods: Non-parametric test was used to assess the quality of electronic services. The assessment of propositions was based on Aqual model and they were prioritized using AHP approach. The AHP approach was used because it directly applies experts’ deductions in the model, and lead to more objective results in the analysis and prioritizing the risks. After evaluating the quality of the electronic services, a multi-criteria decision making frame-work was used to prioritize the proposed solutions. Statistical Analysis Used: Non-parametric tests and AHP approach using Expert Choice software. Results: The results showed that students were satisfied in most of the indicators. Only a few indicators received low satisfaction from students including, design attractiveness, the amount of explanation and details of information, honesty and responsiveness of authorities, and the role of e-services in the user's relationship with university. After interviewing with Information and Communications Technology (ICT) experts at the university, measurement criteria, and solutions to improve the quality were collected. The best solutions were selected by EC software. According to the results, the solution “controlling and improving the process in handling users complaints” is of the utmost importance and authorities
A constrained backpropagation approach for the adaptive solution of partial differential equations.
Rudd, Keith; Di Muro, Gianluca; Ferrari, Silvia
2014-03-01
This paper presents a constrained backpropagation (CPROP) methodology for solving nonlinear elliptic and parabolic partial differential equations (PDEs) adaptively, subject to changes in the PDE parameters or external forcing. Unlike existing methods based on penalty functions or Lagrange multipliers, CPROP solves the constrained optimization problem associated with training a neural network to approximate the PDE solution by means of direct elimination. As a result, CPROP reduces the dimensionality of the optimization problem, while satisfying the equality constraints associated with the boundary and initial conditions exactly, at every iteration of the algorithm. The effectiveness of this method is demonstrated through several examples, including nonlinear elliptic and parabolic PDEs with changing parameters and nonhomogeneous terms.
A new approach to determine {sup 147}Pm in irradiated fuel solutions
Energy Technology Data Exchange (ETDEWEB)
Brennetot, R.; Stadelmann, G.; Caussignac, C.; Gombert, C.; Fouque, M.; Lamouroux, Ch. [CEA, Dept Chim Phys, Serv Etud Comportement Radionucleides, Lab Anal Nucl Isotop et Elementaires, Ctr Etud Sacl, F-91191 Gif Sur Yvette, (France)
2009-07-01
Developments carried out in the Laboratory of Isotopic Nuclear and Elementary Analyses in order to quantify {sup 147}Pm in spent nuclear fuels analyzed at the CEA within the framework of the Burn Up Credit research program for neutronic code validation are presented here. This determination is essential for safety-criticality Studies. The quantity and the nature of the radionuclides in irradiated fuel solutions force LIS to separate the elements of interest before measuring their isotopic content by mass spectrometry. The main objective of this study is to modify the separation protocol used in our laboratory in order to recover and to measure the {sup 147}Pm at the same time as the other lanthanides and actinides determined by mass spectrometry. A very complete study oil synthetic solution (containing or not {sup 147}Pm) Was undertaken in order to determine the yield of the various stages of separation carried out before obtaining the isolated Pm fraction from the whole of the elements present in the spent fuel Solutions. With the lack of natural tracer to carry out the measurement with the isotope dilution technique, the great number of isotopes in fuel, the originality of this work tests oil the use of another present lanthanide in fuel to define the output of separation. The yields were measured at the conclusion of each stage of separation with two others lanthanides in order to show that one of them could be used as a tracer to correct the measurement of the {sup 147}Pm with the separation yield. The total yield (at the conclusion of the two stages of separation) was measured at the same time by ICP-MS and liquid scintillation. This last determination made it possible to validate the use of the Sm-147 (natural) to measure the {sup 147}Pm in ICP-MS since the outputs determined in liquid scintillation and ICP-MS (starting from the radioactive decrease of the source having been used to make the synthetic solution) were equivalent. It is the first time that such
Macromolecular conformation of chitosan in dilute solution: A new global hydrodynamic approach
Morris, Gordon; Castile, J.; Smith, A.; Adams, G. G.; Harding, S. E.
2009-01-01
Chitosans of different molar masses were prepared by storing freshly prepared samples for up to 6 months at either 4, 25 or 40 Â°C. The weight-average molar masses, Mw and intrinsic viscosities, [Î·] were then measured using size exclusion chromatography coupled to multi-angle laser light scattering (SEC-MALLS) and a "rolling ball" viscometer, respectively. The solution conformation of chitosan was then estimated from:(a)the Mark-Houwink-Kuhn-Sakurada (MHKS) power law relationship [Î·] = kMwa...
Analytical Solutions Using Integral Formulations and Their Coupling with Numerical Approaches.
Morel-Seytoux, Hubert J
2015-01-01
Analytical and numerical approaches have their own distinct domains of merit and application. Unfortunately there has been a tendency to use either one or the other even when their domains overlap. Yet there is definite advantage in combining the two approaches. Being relatively new this emerging technique of combining the approaches is, at this stage, more of an art than a science. In this article we suggest approaches for the combination through simple examples. We also suggest that the integral formulation of the analytical problems may have some advantages over the differential formulation. The differential formulation limits somewhat the range of linear system descriptions that can be applied to a variety of practical problems. On the other hand the integral approach tends to focus attention to overall integrated behavior and properties of the system rather than on minute details. This is particularly useful in the coupling with a numerical model as in practice it generally deals also with only the integrated behavior of the system. The thesis of this article is illustrated with some simple stream-aquifer flow exchange examples. © 2014, National GroundWater Association.
The risk-based approach to anti-money laundering: problems and solutions
DEFF Research Database (Denmark)
Simonova, Anna
2011-01-01
Purpose – The purpose of this paper, which is a part of a PhD thesis, is to detect problems associated with the risk-based approach to anti-money laundering (AML), as well as present ways to improve the risk-based approach. Design/methodology/approach – The method is law and economics. The Ph......D thesis itself is also based on a comparative analysis of the Danish and British AML regimes. Findings – The main findings are: failure to develop adequate risk-based AML systems, taking into account varying levels of money laundering risk, is not only to be considered in the context of legal risk...... but also and more importantly in the context of integrity risk; anti-money laundering (AML) has to be made part of financial and non-financial institutions' corporate social responsibility policies; the Risk Analysis Manual provided by the Central Bank of The Netherlands lists very specific...
An overview of modelling approaches and potential solution towards an endgame of tobacco
Halim, Tisya Farida Abdul; Sapiri, Hasimah; Abidin, Norhaslinda Zainal
2015-12-01
A high number of premature mortality due to tobacco use has increased worldwide. Despite control policies being implemented to reduce premature mortality, the rate of smoking prevalence is still high. Moreover, tobacco issues become increasingly difficult since many aspects need to be considered simultaneously. Thus, the purpose of this paper is to present an overview of existing modelling studies on tobacco control system. The background section describes the tobacco issues and its current trends. These models have been categorised according to their modelling approaches either individual or integrated approaches. Next, a framework of modelling approaches based on the integration of multi-criteria decision making, system dynamics and nonlinear programming is proposed, expected to reduce the smoking prevalence. This framework provides guideline for modelling the interaction between smoking behaviour and its impacts, tobacco control policies and the effectiveness of each strategy in healthcare.
Lipparini, Filippo; Lagardère, Louis; Scalmani, Giovanni; Stamm, Benjamin; Cancès, Eric; Maday, Yvon; Piquemal, Jean-Philip; Frisch, Michael J; Mennucci, Benedetta
2014-03-20
We present a new implementation of continuum solvation models for semiempirical Hamiltonians that allows the description of environmental effects on very large molecular systems. In this approach based on a domain decomposition strategy of the COSMO model (ddCOSMO), the solution to the COSMO equations is no longer the computational bottleneck but becomes a negligible part of the overall computation time. In this Letter, we analyze the computational impact of COSMO on the solution of the SCF equations for large to very large molecules, using semiempirical Hamiltonians, for both the new ddCOSMO implementation and the most recent, linear scaling one, based on the fast multipole method. A further analysis is on the simulation of the UV/visible spectrum of a light-harvesting pigment-protein complex. All of the results show how the new ddCOSMO algorithm paves the way to routine computations for large molecular systems in the condensed phase.
Salama, Amgad
2015-06-01
In this work, the experimenting fields approach is applied to the numerical solution of the Navier-Stokes equation for incompressible viscous flow. In this work, the solution is sought for both the pressure and velocity fields in the same time. Apparently, the correct velocity and pressure fields satisfy the governing equations and the boundary conditions. In this technique a set of predefined fields are introduced to the governing equations and the residues are calculated. The flow according to these fields will not satisfy the governing equations and the boundary conditions. However, the residues are used to construct the matrix of coefficients. Although, in this setup it seems trivial constructing the global matrix of coefficients, in other setups it can be quite involved. This technique separates the solver routine from the physics routines and therefore makes easy the coding and debugging procedures. We compare with few examples that demonstrate the capability of this technique.
[Adherence of Type 2 Diabetes Mellitus approach: Current situation and possible solutions].
Orozco-Beltrán, Domingo; Mata-Cases, Manel; Artola, Sara; Conthe, Pedro; Mediavilla, Javier; Miranda, Carlos
2016-01-01
Define the impact and causes of non-adherent type-2 diabetes mellitus (DM2) patients, possible solutions and the role of the different health care professionals involved in the treatment. Structured questionnaire rating by a two-round Delphi method. The study was conducted in the Primary Care settings. The expert panel consisted of renowned medical professionals with extensive experience in diabetes. Assessment through a 9-point Likert scale, of the degree of agreement or disagreement on 131 items grouped into 4 blocks: impact; causes of nonadherence; diagnosis of non-adherence, and possible causes, solutions and role of the different professionals involved in adherence. The participation rate was 76.31%. The primary care health professionals agreed on 110 of the 131 proposals statements (84%), showing agreement on 102 items (77.9%) and disagreement in 8 (6.1%). Consensus was not reached on 21 items. The lack of adherence of DM2 patients makes the achievement of therapeutic control difficult. The medical practice needs to have specific training and enough resources to reduce the impact of the lack of therapeutic compliance. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.
A facile solution-phase approach to transparent and conducting ITO nanocrystal assemblies.
Lee, Jonghun; Lee, Sunghwan; Li, Guanglai; Petruska, Melissa A; Paine, David C; Sun, Shouheng
2012-08-15
Monodisperse 11 nm indium tin oxide (ITO) nanocrystals (NCs) were synthesized by thermal decomposition of indium acetylacetonate, In(acac)(3), and tin bis(acetylacetonate)dichloride, Sn(acac)(2)Cl(2), at 270 °C in 1-octadecene with oleylamine and oleic acid as surfactants. Dispersed in hexane, these ITO NCs were spin-cast on centimeter-wide glass substrates, forming uniform ITO NC assemblies with root-mean-square roughness of 2.9 nm. The assembly thickness was controlled by ITO NC concentrations in hexane and rotation speeds of the spin coater. Via controlled thermal annealing at 300 °C for 6 h under Ar and 5% H(2), the ITO NC assemblies became conductive and transparent with the 146 nm-thick assembly showing 5.2 × 10(-3) Ω·cm (R(s) = 356 Ω/sq) resistivity and 93% transparency in the visible spectral range--the best values ever reported for ITO NC assemblies prepared from solution phase processes. The stable hexane dispersion of ITO NCs was also readily spin-cast on polyimide (T(g) ~360 °C), and the resultant ITO assembly exhibited a comparable conductivity and transparency to the assembly on a glass substrate. The reported synthesis and assembly provide a promising solution to the fabrication of transparent and conducting ITO NCs on flexible substrates for optoelectronic applications.
Matta-Barrera, Romanita; Nafziger, Kristin E.
2013-01-01
State education agencies (SEAs) are central players in initiating and leading new reform efforts. However, traditional approaches to providing public information are not adequate for producing the necessary awareness and support to implement reforms statewide and at the local level. SEAs often have very few staff or other resources devoted to…
Mobarak, E.H.; Shabayek, M.M.; Mulder, J.; Reda, A.H.; Frencken, J.E.F.M.
2011-01-01
OBJECTIVES: To assess the prevalence and severity of dental caries amongst Egyptian adolescents and the prevalence of carious lesions treatable through the atraumatic restorative treatment (ART) approach. SUBJECTS AND METHODS: Using a convenient sample procedure, two secondary schools with a dental
Carol Rice
1995-01-01
Dr. Biswell's approach to fire management balanced fire prevention, suppression, and fuel management. Dr. Biswell maintained that with increased support for fire prevention and fuel management, several profound changes would be anticipated, including a decrease in the number of wildfires, as well as a decrease in requirements for suppression. Interested persons...
Asimow, P. D.; Caracas, R.; Wolf, A. S.; Harvey, J. P.
2016-12-01
To find inner core compositions (X) consistent with geophysical data, we need phase relations of multicomponent metallic systems at high pressure (P) and temperature (T); the stable phase at a given (P,T,X) determines the physical properties. Given the difficulty of experiments under inner core conditions, reliable computations of such phase relations are needed. Despite advances in computational methods and computing power, challenges include proper treatment of solid solutions with their continuous variation in composition and ordering phenomena. We consider here how to predict phase diagrams from thermodynamic models of partly ordered solid solution phases calibrated with density functional theory to obtain static enthalpy (H) and volume (V), density functional perturbation theory and quasiharmonic approximation for vibrational heat capacity, and three approaches to solution theory to parameterize mixing properties. This approach is applied to B2 and HCP structures in the system Fe-FeSi for comparison to experimental data such as Fischer et al. (2013). We computed H and V of 7 compositions across the Fe-FeSi binary for both B2 and HCP structures, every 20 or 40 GPa from 0 to 400 GPa. We used supercells with up to 24 atoms to explore multiple configurations of the atoms. The H differences among clustered, random, and ordered arrangments of the atoms are neither so small as to imply random mixing nor so large that one configuration will dominate. We computed phonon density of states of at least three compositions for each structure in order to define vibrational heat capacity across each binary using ideal mixing and to test this approximation. We then used three different approaches to solid solution theory to fit the mixing properties: (1) Asymmetric regular solution theory, with (P,T)-dependent Margules parameters to describe the excess H but assuming ideal one-site entropy (S) of mixing; (2) the quasichemical model, accounting for optimized Fe-Si pair
Reinke, Charles M; De la Mata Luque, Teofilo M; Su, Mehmet F; Sinclair, Michael B; El-Kady, Ihab
2011-06-01
The problem of designing electromagnetic metamaterials is complicated by the pseudo-infinite parameter space governing such materials. We present a general solution based on group theory for the design and optimization of the electromagnetic properties of metamaterials. Using this framework, the fundamental properties of a metamaterial design, such as anisotropy or magnetic or electrical resonances, can be elucidated based on the symmetry class into which the unit cell falls. This provides a methodology for the inverse problem of design of the electromagnetic properties of a metamaterial. We also present simulations of a zia metamaterial that provides greater design flexibility for tuning the resonant properties of the device than a structure based on a simple split-ring resonator. The power of this zia element is demonstrated by creating bianisotropic, chiral, and biaxial designs using the inverse group-theory procedure outlined in this paper.
Energy Technology Data Exchange (ETDEWEB)
Yang, Hui; Hao, Lijing; Zhao, Naru; Huang, Miaojun [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Du, Chang, E-mail: duchang@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Wang, Yingjun, E-mail: imwangyj@163.com [National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China)
2013-08-15
Nanorod bundles of hydroxyapatite (nrHA) with ordered radiated structure was successfully prepared through hydrothermal treatment, with the hexadecyltrimethylammonium bromide (CTAB) and sodium citrate as surfactant and crystal modifier, respectively. The results showed that the citrate and CTAB played an important role in assembly of nanorods. Moreover, the pH value of the original solution also can influence the final morphology of products. The possible formation mechanism of nanorod bundle structure was discussed in detail. - Highlights: • Nanobundles of hydroxyapatite with ordered radiated structure was prepared. • CTAB regulates the nucleation and growth of crystal. • Calcium citrate modifies the formation of crystals. • Citrate promote the transformation of CTAB micelles. • Citrate causes a heteroepitaxial growth of crystals. - Graphical abstract: Display Omitted.
Indoor localization: novel RSSI approach based on analytical solution and two receivers
Directory of Open Access Journals (Sweden)
A. Warda
2017-11-01
Full Text Available Indoor localization based on trilateration method uses at least three receivers for an accurate localization in 2-D. We performed indoor localization in 2-D using only two receivers, combining algebraic equations for signal strengths into one quadratic equation with transmitter position as unknown and using a specific receiver placement at the two adjacent corners of the room. This receiver arrangement assures unique coordinates of the transmitter position inside a room, rejecting automatically the other solution which appears outside the room volume. The accuracy of the method is numerically tested in a room with dimensions of 9.7 m × 4.7 m × 3 m and shows a mean reconstruction error of 3.4 cm.
Theoretical approaches for predicting the color of rigid dyes in solution.
Di Tommaso, Stefania; Bousquet, Diane; Moulin, Delphine; Baltenneck, Frédéric; Riva, Priscilla; David, Hervé; Fadli, Aziz; Gomar, Jérôme; Ciofini, Ilaria; Adamo, Carlo
2017-05-15
Aiming at developing an affordable and easily implementable computational protocol for routine prediction of spectral properties of rigid molecular dyes, density functional theory, and time-dependent density functional theory were used in conjunction with a vibronic coupling scheme for band shape estimate. To predict the perceived color of molecules in solution, a model has been setup linking the UV-vis spectra predicted at ab initio level to the L*a*b* colorimetric parameters. The results show that a mixed protocol, implying the use of a global hybrid functional for the prediction of adiabatic energy differences and a range separated hybrid for the prediction of potential energy curvature, allows perceived colors to be quantitatively predicted, as demonstrated by the comparison of L*a*b* colorimetric parameters obtained from computed and experimental spectra. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Directory of Open Access Journals (Sweden)
Emran Tohidi
2016-01-01
Full Text Available This article contributes a matrix approach by using Taylor approximation to obtain the numerical solution of one-dimensional time-dependent parabolic partial differential equations (PDEs subject to nonlocal boundary integral conditions. We first impose the initial and boundary conditions to the main problems and then reach to the associated integro-PDEs. By using operational matrices and also the completeness of the monomials basis, the obtained integro-PDEs will be reduced to the generalized Sylvester equations. For solving these algebraic systems, we apply a famous technique in Krylov subspace iterative methods. A numerical example is considered to show the efficiency of the proposed idea.
DEFF Research Database (Denmark)
Oberscheider, Marco; Zazgornik, Jan; Henriksen, Christian Bugge
2013-01-01
the objective of reducing environmental impacts, represented by carbon dioxide equivalent (CO(2)e) emissions, is discussed. The underlying problem is formulated as a multi-depot vehicle routing problem with pickup and delivery and time windows (MDVRPPDTW) and a new iterative solution method is proposed....... For the numerical studies, real-life data are used to generate test instances of different scales concerning the supply chain of biomass power plants. Small ones are taken to validate the optimality of the new approach. Medium and large test instances are solved with respect to minimizing driving times and fuel...
Yvon, Carine; Surman, Andrew J; Hutin, Marie; Alex, Jennifer; Smith, Brian O; Long, De-Liang; Cronin, Leroy
2014-03-24
General synthetic methods for the grafting of peptide chains onto polyoxometalate clusters by the use of general activated precursors have been developed. Using a solution-phase approach, pre-synthesized peptides can be grafted to a metal oxide cluster to produce hybrids of unprecedented scale (up to 30 residues). An adapted solid-phase method allows the incorporation of these clusters, which may be regarded as novel hybrid unnatural amino acids, during the peptide synthesis itself. These methods may open the way for the automated synthesis of peptides and perhaps even proteins that contain "inorganic" amino acids. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Texting As A Discursive Approach For The Production Of Agricultural Solutions
Directory of Open Access Journals (Sweden)
Ronan G. Zagado
2015-08-01
Full Text Available This paper demonstrates how the short messaging service SMS popularly known as texting has facilitated production of solutions to farm issues using the Farmers Text Centre FTC of the Philippine Rice Research PhilRice as the case study. Text messages registered in the FTC database in 2010 covering one cropping season were discourse analyzed. Interpretive qualitative research particularly the Grounded Theory was employed to interprettheorize said data. Since texting is a new emerging discourse in agricultural development Grounded Theory allows the explication of theoretical accounts that explain its existence and impact. Results indicate that timing queries received within working days from 8am to 5pm get speedy response content the easier the question the faster it gets reply length the shorter the message the better and clarity of the querytext message as well as cultural factors such as greetings and terms of respect are all important governing factors in texting for farm use. Moreover analysis reveals that the series of text messages sent back and forth by farmers and agricultural specialist in FTC suggests a dynamic process of negotiation rather than passive information sharing. The analysis further reveals that texting has allowed farmers to have access to a negotiated knowledge rather than a standard scientific recommendation vis--vis the solution to their farm issues. The term negotiated implies that farmers are actively involved in knowledge production via texting. Textholder is coined in this paper to describe farmers and agricultural specialists as co-creators of knowledge in texting as opposed to their traditional role as knowledge generator and user respectively. From the analysis reflections implications and theoretical contributions are drawn in relation to the value of SMSing in agricultural extension and communication.
Symbolic Solution Approach to Wind Turbine based on Doubly Fed Induction Generator Model
DEFF Research Database (Denmark)
Cañas–Carretón, M.; Gómez–Lázaro, E.; Martín–Martínez, S.
2015-01-01
This paper describes an alternative approach based on symbolic computations to simulate wind turbines equipped with Doubly–Fed Induction Generator (DFIG). The actuator disk theory is used to represent the aerodynamic part, and the one-mass model simulates the mechanical part. The 5th......–order induction generator is selected to model the electric machine, being this approach suitable to estimate the DFIG performance under transient conditions. The corresponding non–linear integro-differential equation system has been reduced to a linear state-space system by using an ad-hoc local linearization...... This novel Symbolic Computation (SYMB) method has been implemented by using two different software-packages, with the purpose of solving simultaneously a remarkable number of individual wind turbines models submitted to different wind speed profiles and/or grid voltage waveforms. The obtained results...
Active or passive fiber-chip-alignment: approaches to efficient solutions
Böttger, Gunnar; Schröder, Henning; Jordan, Rafael
2013-02-01
High precision approaches for active and passive alignment and assembly on optoelectronic micro benches have been realized at Fraunhofer IZM for various material systems and different scales. The alignment and reliable mounting of optical subcomponents such as semiconductor laser and photo diodes, micro lenses and micro prisms require far higher mounting and alignment accuracies than for micro-electronic parts. When connecting from silicon photonics chip level to single mode optical fibers, even higher precisions are called for (typically cost, with machine and process robustness for usability in industrial environments. As connecting elements, passive optical components like optical fibers are commonly used. These fragile and flexible elements pose additional challenges in secure picking, placing and fixing, at long lengths vs. small diameters. A very recent and specific approach to use more robust plastic optical fibers (POF) for very short and cost effective optical interconnects by means of wire bonding machines will be presented.
Palm oil industry: A review of the literature on the modelling approaches and potential solution
Zabid, M. Faeid M.; Abidin, Norhaslinda Zainal
2015-12-01
Palm oil industry plays an important role as a backbone to the economy of a country, especially in many developing countries. Various issues related to the palm oil context have been studied rigorously by previous researchers using appropriate modeling approaches. Thus, the purpose of this paper is to present an overview of existing modeling approaches used by researchers in studying several issues in the palm oil industry. However, there are still limited numbers of researches that focus to determine the impact of strategy policies on palm oil studies. Furthermore, this paper introduces an improved system dynamics and genetic algorithm technique to facilitate the policy design process in palm oil industry. The proposed method is expected to become a framework for structured policy design process to assist the policy maker in evaluating and designing appropriate policies.
Integrodifferential approach to solution of eddy currents in linear structures with motion
Czech Academy of Sciences Publication Activity Database
Doležel, Ivo; Karban, P.; Donátová, M.; Šolín, Pavel
2010-01-01
Roč. 80, č. 8 (2010), s. 1636-1646 ISSN 0378-4754 R&D Projects: GA ČR(CZ) GA102/07/0496 Institutional research plan: CEZ:AV0Z20570509 Keywords : eddy currents * integrodifferential approach * numerical analysis Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.812, year: 2010 www.elsevier.com/locate/matcom
A decision science approach for integrating social science in climate and energy solutions
Wong-Parodi, Gabrielle; Krishnamurti, Tamar; Davis, Alex; Schwartz, Daniel; Fischhoff, Baruch
2016-06-01
The social and behavioural sciences are critical for informing climate- and energy-related policies. We describe a decision science approach to applying those sciences. It has three stages: formal analysis of decisions, characterizing how well-informed actors should view them; descriptive research, examining how people actually behave in such circumstances; and interventions, informed by formal analysis and descriptive research, designed to create attractive options and help decision-makers choose among them. Each stage requires collaboration with technical experts (for example, climate scientists, geologists, power systems engineers and regulatory analysts), as well as continuing engagement with decision-makers. We illustrate the approach with examples from our own research in three domains related to mitigating climate change or adapting to its effects: preparing for sea-level rise, adopting smart grid technologies in homes, and investing in energy efficiency for office buildings. The decision science approach can facilitate creating climate- and energy-related policies that are behaviourally informed, realistic and respectful of the people whom they seek to aid.
Directory of Open Access Journals (Sweden)
S. E. Saeed
2014-01-01
Full Text Available Mn2+, Co2+, or Ni2+ monodoped CdS (or ZnS and Mn2+-Co2+-Ni2+ tridoped CdS (or ZnS have been successfully synthesized by novel one-step thermolysis method using thiourea as a sulphur source. The synthesized nanomaterials were characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, and scanning electron microscopy (SEM. It is found that the average diameter and morphology of the synthesized samples varied with the nature of dopant ion. The successful doping of Mn2+-Co2+-Ni2+ tridoped ions into the host CdS (or ZnS was proved by the EDX spectra. The luminescence of CdS is only enhanced when monodoped with Mn2+ whereas it is enhanced when ZnS is either monodoped with Mn2+, Co2+, or Ni2+ or tridoped with Mn2+-Co2+-Ni2+. The synthesized samples could therefore offer opportunities for further fundamental research and technological applications.
Hanifehpour, Younes; Morsali, Ali; Mirtamizdoust, Babak; Joo, Sang Woo; Soltani, Behzad
2017-07-01
Nano-structures of a new supramolecular coordination compound of divalent nickel with the pyrazol (pzH) containing the terminal azide anions, [Ni(pzH) 2 (N 3 ) 2 ] (1), with discrete molecular architecture (DMA) in solid state was synthesized via sonochemical method. The new nanostructure was characterized by scanning electron microscopy, X-ray powder diffraction, IR, and elemental analysis. Compound 1 was structurally characterized by single crystal X-ray diffraction and the single-crystal X-ray data shows that the coordination number of Ni (II) ions is six, (NiN 6 ), with four N-donor atoms from neutral "pzH" ligands and two N-donors from two terminal azide anions. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The structure of the title complex was optimized by density functional theory calculations. Calculated structural parameters and IR spectra for the title complex are consistent with the crystal structure. The NiO nanoparticles were obtained by thermolysis of 1 at 180°C with oleic acid as a surfactant. Copyright © 2017 Elsevier B.V. All rights reserved.
Directory of Open Access Journals (Sweden)
Shengtao Hei
2014-01-01
Full Text Available Porous γ-Fe2O3 nanoparticles were prepared via a solid-state conversion process of a mesoporous iron(III carboxylate crystal, MIL-100(Fe. First, the MIL-100(Fe crystal that served as the template of the metal oxide was synthesized by a low-temperature (<100°C synthesis route. Subsequently, the porous γ-Fe2O3 nanoparticles were fabricated by facile thermolysis of the MIL-100(Fe powders via a two-step calcination treatment. The obtained γ-Fe2O3 was characterized by X-ray diffraction (XRD, N2 adsorption, X-ray photoelectron spectroscopy (XPS, and scanning electron microscopy (SEM techniques, and then used as an adsorbent for heavy metal ions removal in water treatment. This study illustrates that the metal-organic frameworks may be suitable precursors for the fabrication of metal oxides nanomaterials with large specific surface area, and the prepared porous γ-Fe2O3 exhibits a superior adsorption performance for As(V and As(III ions removal in water treatment.
Iron site occupancies in magnetite-ulvospinel solid solution: A new approach using XMCD
Energy Technology Data Exchange (ETDEWEB)
Pearce, C. I.; Henderson, C. M. B.; Telling, N. D.; Pattrick, R. A.D.; Vaughan, D. J.; Charnock, J. M.; Arenholz, E.; Tuna, F.; Coker, V.S.; Laan, G. van der
2009-06-22
Ordering of Fe{sup 3+} and Fe{sup 2+} between octahedral (Oh) and tetrahedral (Td) sites in synthetic members of the magnetite (Fe{sub 3}O{sub 4}) - ulvoespinel (Fe{sub 2}TiO{sub 4}) solid-solution series was determined using Fe L{sub 2,3}-edge X-ray magnetic circular dichroism (XMCD) coupled with electron microprobe and chemical analysis, Ti L-edge spectroscopy, Fe K-edge EXAFS and XANES, Fe{sub 57} Moessbauer spectroscopy, and unit cell parameters. Microprobe analysis, cell edges and chemical FeO determinations showed that the bulk compositions of the samples were stoichiometric magnetite-ulvoespinel solid-solutions. Surface sensitive XMCD showed that the surfaces of these oxide minerals were more sensitive to redox conditions and some samples required re-equilibration with suitable solid-solid buffers. Detailed site-occupancy analysis of these samples gave XMCD-Fe{sup 2+}/Fe{sup 3+} ratios very close to stoichiometric values. L{sub 2,3}-edge spectroscopy showed that Ti{sup 4+} was restricted to Oh sites. XMCD results showed that significant Fe{sup 2+} only entered Td when the Ti content was > 0.40 apfu while Fe{sup 2+} in Oh increased from 1 a.p.f.u in magnetite to a maximum of {approx}1.4 apfu in USP45. As the Ti content increased from this point, the steady increase in Fe{sup 2+} in Td sites was clearly observable in the XMCD spectra, concurrent with a slow decrease in Fe{sup 2+} in Oh sites. Calculated magnetic moments showed a steady decrease from magnetite (4.06 {mu}{sub B}) to USP45 (1.5 {mu}{sub B}) and then a slower decrease towards the value for ulvoespinel (0 {mu}{sub B}). Two of the synthesized samples were also partially maghemitized by re-equilibrating with an oxidizing Ni-NiO buffer and XMCD showed that Fe{sup 2+} oxidation only occurred at Oh sites, with concomitant vacancy formation restricted to this site. This study shows the advantage of using XMCD as a direct measurement of Fe oxidation state in these complex magnetic spinels. These results
An Experimenting Field Approach for the Numerical Solution of Multiphase Flow in Porous Media.
Salama, Amgad; Sun, Shuyu; Bao, Kai
2016-03-01
In this work, we apply the experimenting pressure field technique to the problem of the flow of two or more immiscible phases in porous media. In this technique, a set of predefined pressure fields are introduced to the governing partial differential equations. This implies that the velocity vector field and the divergence at each cell of the solution mesh can be determined. However, since none of these fields is the true pressure field entailed by the boundary conditions and/or the source terms, the divergence at each cell will not be the correct one. Rather the residue which is the difference between the true divergence and the calculated one is obtained. These fields are designed such that these residuals are used to construct the matrix of coefficients of the pressure equation and the right-hand side. The experimenting pressure fields are generated in the solver routine and are fed to the different routines, which may be called physics routines, which return to the solver the elements of the matrix of coefficients. Therefore, this methodology separates the solver routines from the physics routines and therefore results in simpler, easy to construct, maintain, and update algorithms. © 2015, National Ground Water Association.
Rabbani-Chadegani, Azra; Mollaei, Hossein; Sargolzaei, Javad
2017-02-01
Berberine is a natural plant alkaloid with high pharmacological potential. Although its interaction with free DNA has been the subject of several reports, to date there is no work concerning the effect of berberine on nucleoprotein structure of DNA, the nucleosomes. The present study focuses on the binding affinity of berberine to nucleosomes and histone H1 employing various spectroscopic techniques, fluorescence, circular dichroism, thermal denaturation as well as equilibrium dialysis. The results showed that the binding of berberine to nucleosomes is positive cooperative with Ka = 5.57 × 103 M- 1. Berberine quenched with the chromophores of protein moiety of nucleosomes and reduced fluorescence emission intensity at 335 nm with Ksv value of 0.135. Binding of berberine to nucleosomes decreased the absorbance at 210 and 260 nm, produced hypochromicity in thermal denaturation profiles and its affinity to nucleoprotein structure of nucleosomes was much higher than to free DNA. Berberine also exhibited high affinity to histone H1 in solution and the binding was positive cooperative with. Ka = 3.61 × 103 M- 1. Moreover berberine decreased fluorescence emission intensity of H1 by quenching with tyrosine residue in its globular core domain. The circular dichroism profiles demonstrated that the binding of drug induced secondary structural changes in both DNA stacking and histone H1. It is concluded that berberine is genotoxic drug, interacts with nucleosomes and in this process histone H1 is involved to exert its anticancer activity.
A new approach to initial value variables for the Lemaitre-Tolman-Bondi dust solutions
Sussman, R A
2002-01-01
We re-examine the Lemaitre-Tolman-Bondi (LTB) dust solutions by considering as free parameters the initial value functions: Y sub i , rho sub i , sup ( sup 3 sup ) R sub i , obtained by restricting the curvature radius, Y ident to sq root g subtheta theta , the rest mass density, rho, and the three-dimensional Ricci scalar of the rest frames, sup ( sup 3 sup ) R, to an arbitrary regular Cauchy hypersurface, T sub i , marked by constant cosmic time (t = t sub i). Assuming the existence of symmetry centres, we use Y sub i to fix the radial coordinate and the topology (homeomorphic class) of T sub i , while the time evolution is described in terms of an adimensional scale factor y Y/Y sub i. We show that the dynamics, regularity conditions and geometric features of the models are determined by rho sub i , sup ( sup 3 sup ) R sub i and by suitably constructed volume averages and contrast functions expressible in terms of invariant scalars defined in T sub i. These quantities lead to a straightforward characteriza...
Nano-particle drag prediction at low Reynolds number using a direct Boltzmann-BGK solution approach
Evans, B.
2018-01-01
This paper outlines a novel approach for solution of the Boltzmann-BGK equation describing molecular gas dynamics applied to the challenging problem of drag prediction of a 2D circular nano-particle at transitional Knudsen number (0.0214) and low Reynolds number (0.25-2.0). The numerical scheme utilises a discontinuous-Galerkin finite element discretisation for the physical space representing the problem particle geometry and a high order discretisation for molecular velocity space describing the molecular distribution function. The paper shows that this method produces drag predictions that are aligned well with the range of drag predictions for this problem generated from the alternative numerical approaches of molecular dynamics codes and a modified continuum scheme. It also demonstrates the sensitivity of flow-field solutions and therefore drag predictions to the wall absorption parameter used to construct the solid wall boundary condition used in the solver algorithm. The results from this work has applications in fields ranging from diagnostics and therapeutics in medicine to the fields of semiconductors and xerographics.
Scholl, Martha A.; Shanley, James B.; Murphy, Sheila F.; Willenbring, Jane K; Occhi, Marcie; González, Grizelle
2015-01-01
subsurface watershed flowpaths, and better understanding of shallow hillslope and deeper groundwater processes in the watershed will require sub-weekly data and detailed transit time modeling. A combined isotopic and solute chemistry approach can guide further studies to a more comprehensive model of the hydrology, and inform decisions for managing water supply with future changes in climate and land use.
A Model-Based Architecture Approach to Ship Design Linking Capability Needs to System Solutions
2012-06-01
expensive process of engineering and test and evaluation. This thesis attempts to discover how a structured model-based approach can provide a consistent...SYSTEM [ASWCS] W/SSTD W467 3.75 33.4 -12.60 A1240 320 0 8.61 8.61 78 COMBAT DF W468 8.26 33.4 21.00 A1141 0 448 15.47 19.34 449.34 ELECTRONIC TEST ...W529 3.5 35.05 -0.46 NONE 0 0 0 0 121.09 AVIATION FUEL SYS W542 4.86 35.05 -11.00 A1380 30 0 2 2.9 116.92 RAST / RAST CONTROL/HELO CONTROL W588 31.1
Region innovation and investment development: conceptual theoretical approach and business solutions
Directory of Open Access Journals (Sweden)
Zozulya D.M.
2017-01-01
Full Text Available The article describes essential problems of the region business innovation and investment development under current conditions, issues of crisis restrictions negotiation and innovation-driven economy formation. The relevance of the research is defined by the need of effective tools creation for business innovation and investment development and support, which can be applied, first, to increase efficiency of the region industrial activity, then improve production competitiveness on the innovative basis, overcome existing problems and provide sustainable innovation development in the region. The results of conducted research are represented in the article including region innovation and investment development concept model made up by the authors on the basis of system theoretical approach. The tools of the region innovation development defined in the concept model are briefly reviewed in the article. The most important of them include engineering marketing (marketing of scientific and technical innovations, strategic planning, benchmarking, place marketing and business process modeling.
Comparing Solution Approaches for a Complete Model of High School Timetabling
DEFF Research Database (Denmark)
Sørensen, Matias; Stidsen, Thomas Riis
A complex model of high school timetabling is presented, which originates from the problem-setting in the timetabling software of the online high school ERPsystem Lectio. An Integer Programming formulation is described in detail, and a twostage decomposition is suggested. It is proven that both...... of these formulations are NP-hard. A heuristic based on Adaptive Large Neighborhood Search is also applied. Using 100 real-life datasets, comprehensive computational results are provided which show that the ALNS heuristic outperforms the IP approaches. The ALNS heuristic has been incorporated in Lectio......, and is currently available to almost 200 dierent high schools in Denmark. Furthermore, a conversion of the datasets into the XHSTT format is described, and some datasets are made publicly available....
Managing Sport for Public Health: Approaching Contemporary Problems with Traditional Solutions
Directory of Open Access Journals (Sweden)
Anna Aggestål
2015-06-01
Full Text Available In the area of public health, civil society involvement in attaining government objectives on physical activity participation is often carried out by voluntary sport organizations (Agergaard & Michelsen la Cour, 2012; Österlind & Wright, 2014; Skille, 2009; Theeboom, Haudenhuyse, & De Knop, 2010. In Sweden, this responsibility has been given to the Swedish Sport Confederation (SSC, a voluntary and membership-based non-profit organization, granted government authority to govern Swedish sport towards government objectives (Bergsgard & Norberg, 2010; Bolling, 2005. Research has pointed to difficulties for sport organizations to shoulder such responsibilities due to the deeply rooted logic of competition in sport and organizational structures adapted for competitive sport (Skille, 2011; Stenling & Fahlén, 2009. This article focuses on how public health is being constructed, implemented and given meaning within the SSC. Drawing on a critical discourse approach (Fairclough & Fairclough, 2012 this study explores the SSC’s role and position in public health promotion by interviewing SSC representatives and National Sport Organizations’ (NSO general managers. Results indicate how discourses on democracy, equality and physical activity are used to legitimize the SSC’s role in public health. Also, how these discourses are compromised in practice, posing challenges for organized sport in meeting objectives of public health.
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Jens Kutscher
2011-01-01
Full Text Available Female circumcision is a tradition that is widespread and not restricted to predominantly Muslim countries. It is prevalent among all religious groups in many parts of Africa and Western Asia, whether they are Coptic Christians, Ethiopian Jews, or Arab Muslims. Female genital cutting or—more to the point—female genital mutilation (FGM, generally referred to as circumcision, occurs in at least five different forms. Circumcision is essentially a powerful bodily sign of the human—male and female—covenant with God. In the Quran it is reaffirmed in sura al-Nahl and quoted as example in the fatwas endorsing circumcision. It seems to be true that men are hardly involved in the actual decision in favour of female genital cutting. A man should not interfere in the decision of women to be circumcised. It is practiced and transmitted among women and midwives. Only sometimes is a (male or female physician involved. On the basis of Islamic normativity, mirrored in fatwas, this paper aims to examine a very ambivalent approach concerning female genital mutilation.
Bretos, Iñigo; Calzada, M. Lourdes
The ever-growing environmental awareness in our lives has also been extended to the electroceramics field during the past decades. Despite the strong regulations that have come up (RoHS directive), a number of scientists work on ferroelectric thin film ceramics containing lead. Although the use of these materials in piezoelectric devices is exempt from the RoHS directive, successful ways of decreasing toxic load must be considered a crucial challenge. Within this framework, a few significant advances are presented here, based on different Chemical Solution Deposition strategies. Firstly, the UV sol-gel photoannealing technique (Photochemical Solution Deposition) avoids the volatilisation of hazardous lead from lead-based ferroelectric films, usually observed at conventional annealing temperatures. The key point of this approach lies in the photo-excitation of a few organic components in the gel film. There is also a subsequent annealing of the photo-activated film at temperatures low enough to prevent lead volatilisation, but allowing crystallisation of the pure perovskite phase. Ozonolysis of the films is also promoted when UV-irradiation is carried out in an oxygen atmosphere. This is known to improve electrical response. By this method, nominally stoichiometric solution (i.e., a solution without PbO-excess) derived films with reliable properties, and free of compositional gradients, may be prepared at temperatures as low as 450°C. A PtxPb interlayer between the ferroelectric film and the Pt silicon substrate is observed in the heterostructure of the low-temperature processed films. This is when lead excesses are present in their microstructure. The influence of this interface on the compositional depth profile of the films will be discussed. We will evaluate the feasibility of the UV sol-gel photoannealing technique in fabricating functional films while fulfilling environmental and technological aspects (like integration with silicon IC technology). The second
Matsevych, Oleh Yevhenovych; Koto, Modise Zacharia; Aldous, Colleen
2017-08-01
Therapeutic laparoscopy (TL) for penetrating abdominal trauma (PAT) is controversial because the management of multiple bowel injuries is challenging and the conversion rate is high. However, the laparoscopic-assisted approach (LAA) allows easy management of multiple bowel injuries but not investigated in a trauma setting. The aim of this study was to investigate its role in management of multiple bowel injuries and to compare LAA with therapeutic laparoscopy performed fully laparoscopically (FTL). All adult patients with PAT managed with TL over four-year period were analyzed. Intraoperative findings, trauma scoring, grading of bowel injuries, related procedures, outcomes and length of hospital stay (LOS) were compared between LAA and FTL groups. Seventy two (53%) patients were in the FTL group and 65 (47%) in the LAA group. The majority of patients presented with stab wounds. Colonic and small bowel injuries were more common in the LAA group (19 versus 17 and 47 versus 8, respectively). The higher number of bowel repairs, resections and anastomosis were performed in the LAA group. The ISS was higher in the FTL group (13 versus 11, p = 0.02), and the PATI was higher in the LAA group (6 versus 10, p < 0.001). Nine patients in the FTL group suffered Clavien-Dindo grade 3 complications and 11 patients in the LAA group. There was one death in each group. No missed injuries were reported. There was no significant difference in LOS between groups. The LAA is safe in the management of stable patients with PAT. It can used for management of multiple bowel injuries instead of a conversion to laparotomy. It provides benefits of minimally invasive surgery and the speed and versatility of laparotomy. Moreover, the LAA seems not to be inferior to entirely laparoscopic therapeutic procedures. More studies are needed to compare LAA with FTL and laparotomy. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Solution of two nucleon systems using vector variables in momentum space - an innovative approach
Veerasamy, Saravanan
An alternate formalism that uses vector variables to treat the two-body Lippmann-Schwinger equation for realistic nucleon-nucleon potentials in momentum space is discussed in this thesis. The formalism uses the symmetry properties of the nucleon-nucleon potential and expands the nucleon-nucleon potential in terms of six linearly independent spin operators. The alternate formalism discussed in this thesis brings to light the role of time-odd spin operators. The vector variable formalism's treatment of spin degrees of freedom heavily depends on the analytical computation of hundreds of algebraic expression. A mathematical framework and computer algorithms for an automated symbolic reduction of algebraic expressions into scalar functions of vector variables are explained in this thesis. The vector variable formalism requires nucleon-nucleon potentials that are in operator form as input. The configuration space nucleon-nucleon potential Argonne V18 is one such potential that can be used for relativistic energies if it can be computed efficiently in momentum space. This thesis develops an efficient numerical technique using Chebyshev approximation to compute the Argonne V18 potential in momentum-space. The tools discussed in this thesis, the algebraic system and the efficient computation of the Argonne V18 potential in momentum space are tested by computing the binding energy and bound state wavefunctions of the deuteron using the vector variable approach. The results were successful and the first step towards a higher goal of using vector formalism of the three-body Faddeev equations for intermediate and high energies has been made.
Zijp, M.C.; Posthuma, L.; Wintersen, A.; Devilee, J.; Swartjes, F.A.
2016-01-01
This paper introduces Solution-focused Sustainability Assessment (SfSA), provides practical guidance formatted as a versatile process framework, and illustrates its utility for solving a wicked environmental management problem. Society faces complex and increasingly wicked environmental problems for
Tehrani, Mahnaz Saghanejhad; Zare-Dorabei, Rouholah
2016-05-01
MIL-68(Al) as a metal-organic framework (MOF) was synthesized and characterized by different techniques such as SEM, BET, FTIR, and XRD analysis. This material was then applied for simulations removal of malachite green (MG) and methylene blue (MB) dyes from aqueous solutions using second order derivative spectrophotometric method (SODS) which was applied to resolve the overlap between the spectra of these dyes. The dependency of dyes removal efficiency in binary solutions was examined and optimized toward various parameters including initial dye concentration, pH of the solution, adsorbent dosage and ultrasonic contact time using central composite design (CCD) under response surface methodology (RSM) approach. The optimized experimental conditions were set as pH 7.78, contact time 5 min, initial MB concentration 22 mg L- 1, initial MG concentration 12 mg L- 1 and adsorbent dosage 0.0055 g. The equilibrium data was fitted to isotherm models such as Langmuir, Freundlich and Tempkin and the results revealed the suitability of the Langmuir model. The maximum adsorption capacity of 666.67 and 153.85 mg g- 1 was obtained for MB and MG removal respectively. Kinetics data fitting to pseudo-first order, pseudo-second order and Elovich models confirmed the applicability of pseudo-second order kinetic model for description of the mechanism and adsorption rate. Dye-loaded MIL-68(Al) can be easily regenerated using methanol and applied for three frequent sorption/desorption cycles with high performance. The impact of ionic strength on removal percentage of both dyes in binary mixture was studied by using NaCl and KCl soluble salts at different concentrations. According to our findings, only small dosage of the proposed MOF is considerably capable to remove large amounts of dyes at room temperature and in very short time that is a big advantage of MIL-68(Al) as a promising adsorbent for adsorptive removal processes.
Ran, J.; Ditmar, P.; Klees, R.; Farahani, H. H.
2017-09-01
We present an improved mascon approach to transform monthly spherical harmonic solutions based on GRACE satellite data into mass anomaly estimates in Greenland. The GRACE-based spherical harmonic coefficients are used to synthesize gravity anomalies at satellite altitude, which are then inverted into mass anomalies per mascon. The limited spectral content of the gravity anomalies is properly accounted for by applying a low-pass filter as part of the inversion procedure to make the functional model spectrally consistent with the data. The full error covariance matrices of the monthly GRACE solutions are properly propagated using the law of covariance propagation. Using numerical experiments, we demonstrate the importance of a proper data weighting and of the spectral consistency between functional model and data. The developed methodology is applied to process real GRACE level-2 data (CSR RL05). The obtained mass anomaly estimates are integrated over five drainage systems, as well as over entire Greenland. We find that the statistically optimal data weighting reduces random noise by 35-69%, depending on the drainage system. The obtained mass anomaly time-series are de-trended to eliminate the contribution of ice discharge and are compared with de-trended surface mass balance (SMB) time-series computed with the Regional Atmospheric Climate Model (RACMO 2.3). We show that when using a statistically optimal data weighting in GRACE data processing, the discrepancies between GRACE-based estimates of SMB and modelled SMB are reduced by 24-47%.
Sheth, Poonam; Sandell, Dennis; Conti, Denise S; Holt, Jay T; Hickey, Anthony J; Saluja, Bhawana
2017-09-01
Metered dose inhalers (MDIs) are complex drug-device combination products widely used to treat pulmonary disorders. The efficacy, driven by aerosol performance of the products, depends on a multitude of factors including, but not limited to, the physicochemical properties of drug and nature and amount of excipient(s). Under the quality by design (QbD) paradigm, systematic investigations are necessary to understand how changes in critical quality attributes (CQAs) of formulation, device, and manufacturing process influence key product performance parameters, such as delivered dose (DD) and fine particle dose (FPD). The purpose of this work is to provide a better understanding of the effects of different levels of excipients and drug particle size distribution on the aerosol performance of MDI products, while using two fundamentally different MDI products as relevant model systems, Proventil® HFA (albuterol sulfate suspension) and Qvar® (beclomethasone dipropionate solution). These MDI products, as model systems, provided mid-points around which a design of experiments (DOE), consisting of 22 suspension and 9 solution MDI formulations, were defined and manufactured. The DOE included formulations factors with varying ethanol (2 to 20% w/w and 7 to 9% w/w for the suspension and solution, respectively) and oleic acid concentrations (0.005 to 0.25% w/w and 0 to 2% w/w for the suspension and solution, respectively) and drug volumetric median particle size distribution (PSD D50, 1.4 to 2.5 μm for the suspension). The MDI formulations were analyzed using compendial methods to elucidate the effect of these formulation variables (ethanol, oleic acid, and PSD D50) on DD and FPD. The outcomes of this study allowed defining design spaces for the formulation factors, such that DD and FPD would remain within specific pre-defined requirements. The systematic approach utilized in this work can contribute as a QbD tool to evaluate the extent to which the formulation factors
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Junling Zhang
2016-03-01
Full Text Available Emergency management is vital in implementing sustainable community development, for which community planning must include emergency response solutions to potential natural and manmade hazards. To help maintain such solution repository, we investigate effective fuzzy multi-criteria group decision making (FMCGDM approaches for the complex problems of evaluating alternative emergency response solutions, where weights for decision makers and criteria are unknown due to problem complexity. We employ interval-valued dual hesitant fuzzy (IVDHF set to address decision hesitancy more effectively. Based on IVDHF assessments, we develop a deviation maximizing model to compute criteria weights and another compatibility maximizing model to calculate weights for decision makers. Then, two ideal-solution-based FMCGDM approaches are proposed: (i by introducing a synthesized IVDHF group decision matrix into TOPSIS, we develop an IVDHF-TOPSIS approach for fuzzy group settings; (ii when emphasizing both maximum group utility and minimum individual regret, we extend VIKOR to develop an IVDHF-VIKOR approach, where the derived decision makers’ weights are utilized to obtain group decision matrix and the determined criteria weights are integrated to reflect the relative importance of distances from the compromised ideal solution. Compared with aggregation-operators-based approach, IVDHF-TOPSIS and IVDHF-VIKOR can alleviate information loss and computational complexity. Numerical examples have validated the effectiveness of the proposed approaches.
Lan, Bo; Lowe, Michael J. S.; Dunne, Fionn P. E.
2015-10-01
A new spherical convolution approach has been presented which couples HCP single crystal wave speed (the kernel function) with polycrystal c-axis pole distribution function to give the resultant polycrystal wave speed response. The three functions have been expressed as spherical harmonic expansions thus enabling application of the de-convolution technique to enable any one of the three to be determined from knowledge of the other two. Hence, the forward problem of determination of polycrystal wave speed from knowledge of single crystal wave speed response and the polycrystal pole distribution has been solved for a broad range of experimentally representative HCP polycrystal textures. The technique provides near-perfect representation of the sensitivity of wave speed to polycrystal texture as well as quantitative prediction of polycrystal wave speed. More importantly, a solution to the inverse problem is presented in which texture, as a c-axis distribution function, is determined from knowledge of the kernel function and the polycrystal wave speed response. It has also been explained why it has been widely reported in the literature that only texture coefficients up to 4th degree may be obtained from ultrasonic measurements. Finally, the de-convolution approach presented provides the potential for the measurement of polycrystal texture from ultrasonic wave speed measurements.
Tomba, J. Pablo
2015-01-01
The thermodynamic formalism of ideal solutions is developed in most of the textbooks postulating a form for the chemical potential of a generic component, which is adapted from the thermodynamics of ideal gas mixtures. From this basis, the rest of useful thermodynamic properties can be derived straightforwardly without further hypothesis. Although…
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Seitz, M.G.
1982-01-01
Reviewed in this statement are methods of preparing solutions to be used in laboratory experiments to examine technical issues related to the safe disposal of nuclear waste from power generation. Each approach currently used to prepare solutions has advantages and any one approach may be preferred over the others in particular situations, depending upon the goals of the experimental program. These advantages are highlighted herein for three approaches to solution preparation that are currently used most in studies of nuclear waste disposal. Discussion of the disadvantages of each approach is presented to help a user select a preparation method for his particular studies. Also presented in this statement are general observations regarding solution preparation. These observations are used as examples of the types of concerns that need to be addressed regarding solution preparation. As shown by these examples, prior to experimentation or chemical analyses, laboratory techniques based on scientific knowledge of solutions can be applied to solutions, often resulting in great improvement in the usefulness of results.
Urmanov, Aleksey Mikhaylovich
Engineering problems are often ill-posed, i.e. cannot be solved by conventional data-driven methods such as parametric linear and nonlinear regression or neural networks. A method of regularization that is used for the solution of ill-posed problems requires an a priori choice of the regularization parameter. Several regularization parameter selection methods have been proposed in the literature, yet, none is resistant to model misspecification. Since almost all models are incorrectly or approximately specified, misspecification resistance is a valuable option for engineering applications. Each data-driven method is based on a statistical procedure which can perform well on one data set and can fail on other. Therefore, another useful feature of a data-driven method is robustness. This dissertation proposes a methodology of developing misspecification-resistant and robust regularization parameter selection methods through the use of the information complexity approach. The original contribution of the dissertation to the field of ill-posed inverse problems in engineering is a new robust regularization parameter selection method. This method is misspecification-resistant, i.e. it works consistently when the model is misspecified. The method also improves upon the information-based regularization parameter selection methods by correcting inadequate penalization of estimation inaccuracy through the use of the information complexity framework. Such an improvement makes the proposed regularization parameter selection method robust and reduces the risk of obtaining grossly underregularized solutions. A method of misspecification detection is proposed based on the discrepancy between the proposed regularization parameter selection method and its correctly specified version. A detected misspecification indicates that the model may be inadequate for the particular problem and should be revised. The superior performance of the proposed regularization parameter selection
An Ecosocial Approach to Well-Being: A Solution to the Wicked Problems in the Era of Anthropocene
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Arto O. Salonen
2015-07-01
Full Text Available Modern Western states have a history of the thinking tradition, where the development of human societies is seen as independent from ecological constraints. Our thinking is a social construction, a product of the human mind. It can be changed. In this article we describe a new approach to well-being called an Ecosocial Approach to Well-Being (EAW. It is a holistic and multidisciplinary approach to well-being that will facilitate the analysis and management of the world’s complexity from a socio-ecological perspective. The EAW is based on the fact that without the well-functioning biosphere there can be no society and without a society there can be no societal functions, including an economy. Fundamentally all wicked problems in the era of Anthropocene are global and have social and environmental backgrounds. A more holistic and multi-disciplinary systems thinking is needed to analyze and manage the causal complexity of the world in which we live. The EAW asks us to focus on post-material values because they are only loosely coupled with resource consumption. On the finite planet that is the question of what is enough and what is good for us. The EAW leads us maximizing psychological well-being and nurturing social harmony and cohesion. The EAW holds promise not only for solving social and ecological problems but also for helping people to be happier. It emphasizes human relationships and the meaningfulness of people’s unique lives. If people properly reflected on their values, especially what is ultimately good for those they care about, most of the wicked problems would be resolved.How to reference this articleSalonen, A. O., & Konkka, J. (2015. An Ecosocial Approach to Well-Being: A Solution to the Wicked Problems in the Era of Anthropocene. Foro de Educación, 13(19, 19-34. doi: http://dx.doi.org/10.14516/fde.2015.013.019.002
Lv, Ying; Huang, Guohe; Sun, Wei
2013-01-01
A scenario-based interval two-phase fuzzy programming (SITF) method was developed for water resources planning in a wetland ecosystem. The SITF approach incorporates two-phase fuzzy programming, interval mathematical programming, and scenario analysis within a general framework. It can tackle fuzzy and interval uncertainties in terms of cost coefficients, resources availabilities, water demands, hydrological conditions and other parameters within a multi-source supply and multi-sector consumption context. The SITF method has the advantage in effectively improving the membership degrees of the system objective and all fuzzy constraints, so that both higher satisfactory grade of the objective and more efficient utilization of system resources can be guaranteed. Under the systematic consideration of water demands by the ecosystem, the SITF method was successfully applied to Baiyangdian Lake, which is the largest wetland in North China. Multi-source supplies (including the inter-basin water sources of Yuecheng Reservoir and Yellow River), and multiple water users (including agricultural, industrial and domestic sectors) were taken into account. The results indicated that, the SITF approach would generate useful solutions to identify long-term water allocation and transfer schemes under multiple economic, environmental, ecological, and system-security targets. It can address a comparative analysis for the system satisfactory degrees of decisions under various policy scenarios. Moreover, it is of significance to quantify the relationship between hydrological change and human activities, such that a scheme on ecologically sustainable water supply to Baiyangdian Lake can be achieved. Copyright © 2012 Elsevier B.V. All rights reserved.
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Keita Takahashi
2015-04-01
Full Text Available Product Lifecycle Management (PLM ranges from design concepts of products to disposal. In this paper, we focus on the production planning phase in PLM, which is related to process planning and production scheduling and so on. In this study, key decisions for the creation of production plans are defined as production-planning attributes. Production-planning attributes correlate complexly in production-planning problems. Traditionally, the production-planning problem splits sub-problems based on experiences, because of the complexity. In addition, the orders in which to solve each sub-problem are determined by priorities between sub-problems. However, such approaches make solution space over-restricted and make it difficult to find a better solution. We have proposed a representation of combinations of alternatives in production-planning attributes by using Zero-Suppressed Binary Decision Diagrams. The ZDD represents only feasible combinations of alternatives that satisfy constraints in the production planning. Moreover, we have developed a solution search method that solves production-planning problems with ZDDs. In this paper, we propose an approach for managing solution candidates by ZDDs׳ network for addressing larger production-planning problems. The network can be created by linkages of ZDDs that express constraints in individual sub-problems and between sub-problems. The benefit of this approach is that it represents solution space, satisfying whole constraints in the production planning. This case study shows that the validity of the proposed approach.
Chandrasekaran, Suryanarayanan; Aghtar, Mortaza; Valleau, Stéphanie; Aspuru-Guzik, Alán; Kleinekathöfer, Ulrich
2015-08-06
Studies on light-harvesting (LH) systems have attracted much attention after the finding of long-lived quantum coherences in the exciton dynamics of the Fenna-Matthews-Olson (FMO) complex. In this complex, excitation energy transfer occurs between the bacteriochlorophyll a (BChl a) pigments. Two quantum mechanics/molecular mechanics (QM/MM) studies, each with a different force-field and quantum chemistry approach, reported different excitation energy distributions for the FMO complex. To understand the reasons for these differences in the predicted excitation energies, we have carried out a comparative study between the simulations using the CHARMM and AMBER force field and the Zerner intermediate neglect of differential orbital (ZINDO)/S and time-dependent density functional theory (TDDFT) quantum chemistry methods. The calculations using the CHARMM force field together with ZINDO/S or TDDFT always show a wider spread in the energy distribution compared to those using the AMBER force field. High- or low-energy tails in these energy distributions result in larger values for the spectral density at low frequencies. A detailed study on individual BChl a molecules in solution shows that without the environment, the density of states is the same for both force field sets. Including the environmental point charges, however, the excitation energy distribution gets broader and, depending on the applied methods, also asymmetric. The excitation energy distribution predicted using TDDFT together with the AMBER force field shows a symmetric, Gaussian-like distribution.
Wada, Y.; Florke, M.; Hanasaki, N.; Eisner, S.; Fischer, G.; Tramberend, S.; Satoh, Y.; van Vliet, M. T. H.; Yillia, P.; Ringler, C.;
2016-01-01
To sustain growing food demand and increasing standard of living, global water use increased by nearly 6 times during the last 100 years, and continues to grow. As water demands get closer and closer to the water availability in many regions, each drop of water becomes increasingly valuable and water must be managed more efficiently and intensively. However, soaring water use worsens water scarcity conditions already prevalent in semi-arid and arid regions, increasing uncertainty for sustainable food production and economic development. Planning for future development and investments requires that we prepare water projections for the future. However, estimations are complicated because the future of the world's waters will be influenced by a combination of environmental, social, economic, and political factors, and there is only limited knowledge and data available about freshwater resources and how they are being used. The Water Futures and Solutions (WFaS) initiative coordinates its work with other ongoing scenario efforts for the sake of establishing a consistent set of new global water scenarios based on the shared socio-economic pathways (SSPs) and the representative concentration pathways (RCPs). The WFaS "fast track" assessment uses three global water models, namely H08, PCR-GLOBWB, and WaterGAP. This study assesses the state of the art for estimating and projecting water use regionally and globally in a consistent manner. It provides an overview of different approaches, the uncertainty, strengths and weaknesses of the various estimation methods, types of management and policy decisions for which the current estimation methods are useful. We also discuss additional information most needed to be able to improve water use estimates and be able to assess a greater range of management options across the water-energy-climate nexus.
A New Heuristic Providing an Effective Initial Solution for a Simulated Annealing approach to Energy Resource Scheduling in Smart Grids
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Sousa, Tiago M; Morais, Hugo; Castro, R.
2014-01-01
scheduling problem. Therefore, the use of metaheuristics is required to obtain good solutions in a reasonable amount of time. This paper proposes two new heuristics, called naive electric vehicles charge and discharge allocation and generation tournament based on cost, developed to obtain an initial solution...
Tariq, Hira; Akram, Ghazala
2017-05-01
In this article, new exact analytical solutions of some nonlinear evolution equations (NLEEs) arising in science, engineering and mathematical physics, namely time fractional Cahn-Allen equation and time fractional Phi-4 equation are developed using tanh method by means of fractional complex transform. The obtained results are demonstrated by graphs for the new solutions.
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Gabriel Amador
2016-05-01
Full Text Available In this work, after reviewing two different ways to solve Riccati systems, we are able to present an extensive list of families of integrable nonlinear Schrödinger (NLS equations with variable coefficients. Using Riccati equations and similarity transformations, we are able to reduce them to the standard NLS models. Consequently, we can construct bright-, dark- and Peregrine-type soliton solutions for NLS with variable coefficients. As an important application of solutions for the Riccati equation with parameters, by means of computer algebra systems, it is shown that the parameters change the dynamics of the solutions. Finally, we test numerical approximations for the inhomogeneous paraxial wave equation by the Crank-Nicolson scheme with analytical solutions found using Riccati systems. These solutions include oscillating laser beams and Laguerre and Gaussian beams.
Energy Technology Data Exchange (ETDEWEB)
Medeiros, Adriana S. [CAPES Foundation, Ministry of Education of Brazil, 70040-020, Brasilia, Brazil, Proc.BEX 1958/13-5 (Brazil); Lozano, J.C.; Prieto, C. [Universidad de Salamanca, 37008, Salamanca (Spain); Blanco Rodriguez, P.; Vera Tome, F. [Universidad de Extremadura, 06006, Badajoz (Spain)
2014-07-01
The centrifugation technique is tested as a methodology for extraction of soil solution, for further characterization, in order to elucidate its contribution to the speciation of radionuclides, particularly uranium, in radioactively contaminated soils, as well as the determination of its availability for vegetation. Centrifugation of a previously saturated soil core provides the soil solution with a specific origin inside the soil sample. In such way that the different soil solution origin, associate to the effective pressure applied to the soil core, will reflect different distribution coefficients which affect the radionuclide availability definition. Speciation of radionuclides in the soil solution can be also conditioned by this water origin. The development of this methodology relating to technical challenges faces materials suitable for the centrifugation process, both in terms of mechanical properties and chemical inertness. This paper reports the preparation of ceramic pellets of perlite produced with the intention of replacing glass pellets, used inserts in support to soils coupled with centrifuges. The characterization of porosity and the test of its chemical inertness and mechanical strength to the centrifugation process have been performed. Porosity characterization is required to control the saturation gradient, which conditions the flow of water from the soil. Its mechanical adequacy was tested by subjecting the pellets to the centrifugation process and assessing its integrity end. Chemical inertia was measured by placing the tablets in aqueous solutions of known composition and then evaluating the presence or absence of elements in this solution, after on time of contact between them. (authors)
Mahomed, F. M.
2014-01-01
In this communication, we utilize some basic symmetry reductions to transform the governing nonlinear partial differential equations arising in the study of third-grade fluid flows into ordinary differential equations. We obtain some simple closed-form steady-state solutions of these reduced equations. Our solutions are valid for the whole domain [0,∞) and also satisfy the physical boundary conditions. We also present the numerical solutions for some of the underlying equations. The graphs corresponding to the essential physical parameters of the flow are presented and discussed. PMID:25143962
Kühn, Susanne; Werven, Van Bernike; Oyen, Van Albert; Meijboom, André; Bravo Rebolledo, Elisa L.; Franeker, Van Jan A.
2017-01-01
In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests
Lucas, P.; Van Zuijlen, A.H.; Bijl, H.
2009-01-01
Mesh adaptation is a fairly established tool to obtain numerically accurate solutions for flow problems. Computational efficiency is, however, not always guaranteed for the adaptation strategies found in literature. Typically excessive mesh growth diminishes the potential efficiency gain. This
Energy Technology Data Exchange (ETDEWEB)
Shabani, Hamid [University of Sistan and Baluchestan, Physics Department, Faculty of Sciences, Zahedan (Iran, Islamic Republic of); Ziaie, Amir Hadi [Islamic Azad University, Department of Physics, Kahnooj Branch, Kerman (Iran, Islamic Republic of)
2017-05-15
Very recently, Josset and Perez (Phys. Rev. Lett. 118:021102, 2017) have shown that a violation of the energy-momentum tensor (EMT) could result in an accelerated expansion state via the appearance of an effective cosmological constant, in the context of unimodular gravity. Inspired by this outcome, in this paper we investigate cosmological consequences of a violation of the EMT conservation in a particular class of f(R,T) gravity when only the pressure-less fluid is present. In this respect, we focus on the late time solutions of models of the type f(R,T) = R + βΛ(-T). As the first task, we study the solutions when the conservation of EMT is respected, and then we proceed with those in which violation occurs. We have found, provided that the EMT conservation is violated, that there generally exist two accelerated expansion solutions of which the stability properties depend on the underlying model. More exactly, we obtain a dark energy solution for which the effective equation of state depends on the model parameters and a de Sitter solution. We present a method to parametrize the Λ(-T) function, which is useful in a dynamical system approach and has been employed in the model. Also, we discuss the cosmological solutions for models with Λ(-T) = 8πG(-T){sup α} in the presence of ultra-relativistic matter. (orig.)
Schneider, Arnaud R; Ponthieu, Marie; Cancès, Benjamin; Conreux, Alexandra; Morvan, Xavier; Gommeaux, Maxime; Marin, Béatrice; Benedetti, Marc F
2016-06-01
Trace element (TE) speciation modelling in soil solution is controlled by the assumptions made about the soil solution composition. To evaluate this influence, different assumptions using Visual MINTEQ were tested and compared to measurements of free TE concentrations. The soil column Donnan membrane technique (SC-DMT) was used to estimate the free TE (Cd, Cu, Ni, Pb and Zn) concentrations in six acidic soil solutions. A batch technique using DAX-8 resin was used to fractionate the dissolved organic matter (DOM) into four fractions: humic acids (HA), fulvic acids (FA), hydrophilic acids (Hy) and hydrophobic neutral organic matter (HON). To model TE speciation, particular attention was focused on the hydrous manganese oxides (HMO) and the Hy fraction, ligands not considered in most of the TE speciation modelling studies in soil solution. In this work, the model predictions of free ion activities agree with the experimental results. The knowledge of the FA fraction seems to be very useful, especially in the case of high DOM content, for more accurately representing experimental data. Finally, the role of the manganese oxides and of the Hy fraction on TE speciation was identified and, depending on the physicochemical conditions of the soil solution, should be considered in future studies. Copyright © 2016 Elsevier Ltd. All rights reserved.
Vasileiou, Zoe; Barlos, Kostas; Gatos, Dimitrios
2009-12-01
The RING finger domain of the Mdm2, located at the C-terminus of the protein, is necessary for regulation of p53, a tumor suppressor protein. The 48-residues long Mdm2 peptide is an important target for studying its interaction with small anticancer drug candidates. For the chemical synthesis of the Mdm2 RING finger domain, the fragment condensation on solid-phase and the fragment condensation in solution were studied. The latter method was performed using either protected or free peptides at the C-terminus as the amino component. Best results were achieved using solution condensation where the N-component was applied with the C-terminal carboxyl group left unprotected. The developed method is well suited for large-scale synthesis of Mdm2 RING finger domain, combining the advantages of both solid-phase and solution synthesis. (c) 2009 European Peptide Society and John Wiley & Sons, Ltd.
Qin, Bo; Tian, Bo; Wang, Yu-Feng; Shen, Yu-Jia; Wang, Ming
2017-10-01
Under investigation in this paper are the Belov-Chaltikian (BC), Leznov and Blaszak-Marciniak (BM) lattice equations, which are associated with the conformal field theory, UToda(m_1,m_2) system and r-matrix, respectively. With symbolic computation, the Bell-polynomial approach is developed to directly bilinearize those three sets of differential-difference nonlinear evolution equations (NLEEs). This Bell-polynomial approach does not rely on any dependent variable transformation, which constitutes the key step and main difficulty of the Hirota bilinear method, and thus has the advantage in the bilinearization of the differential-difference NLEEs. Based on the bilinear forms obtained, the N-soliton solutions are constructed in terms of the N × N Wronskian determinant. Graphic illustrations demonstrate that those solutions, more general than the existing results, permit some new properties, such as the solitonic propagation and interactions for the BC lattice equations, and the nonnegative dark solitons for the BM lattice equations.
Directory of Open Access Journals (Sweden)
Martin G. H.
2006-12-01
Full Text Available The current regulations concerning atmospheric pollutant discharge by incinerators, and the determination of public authorities to do away with waste dumps as of the beginning of the next decade are leading to a heavy demand for new installations. Areas which still use the dump method will have to equip themselves with purpose-built plants, and incinerators built more than twenty years ago will in many cases have to make way for more efficient units which meet the requirements of the legislators. In all, more than 200 new installations should be erected within the next ten years in France alone. The market prospects are even greater in Europe as a whole, since the problem of waste disposal exists under very much the same conditions in neighbouring countries. Les réglementations en vigueur relatives aux rejets atmosphériques des incinérateurs et la volonté des pouvoirs publics de supprimer les décharges dès le début de la prochaine décennie conduisent à une forte demande en installations neuves. Les régions qui pratiquent encore la mise en décharge devront s'équiper d'usines de traitement ad hoc et les incinérateurs construits il y a plus d'une vingtaine d'années devront souvent céder la place à des unités plus performantes répondant aux exigences du législateur. Au total, plus de 200 installations nouvelles devraient voir le jour d'ici dix ans rien qu'en France. Les perspectives de marché sont encore plus grandes en Europe, puisque le problème de l'élimination des déchets se pose sensiblement dans les mêmes termes dans les pays voisins.
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Antonio Gledson Goulart
2013-12-01
Full Text Available In this paper, the equation for the gravity wave spectra in mean atmosphere is analytically solved without linearization by the Adomian decomposition method. As a consequence, the nonlinear nature of problem is preserved and the errors found in the results are only due to the parameterization. The results, with the parameterization applied in the simulations, indicate that the linear solution of the equation is a good approximation only for heights shorter than ten kilometers, because the linearization the equation leads to a solution that does not correctly describe the kinetic energy spectra.
DEFF Research Database (Denmark)
Sanz Landaluze, Jon; Egsgaard, Helge; Morales Munoz, Clara
2014-01-01
This study focused on developing a surface cleaning treatment for one type of commercially available plasticized poly(vinyl chloride). The effects of cleaning solutions on samples of plasticized poly(vinyl chloride) were examined by several methods. The sample surface, prior to and after artificial...... solutions for the plasticized poly(vinyl chloride) used in the study was found. In addition, a specific method to tailor cleaning mixtures for plasticized poly(vinyl chloride) objects was developed by means of Hildebrand solubility parameters and the formulation of a Plasticizer Index calculated...... cleaning methods for plasticized poly(vinyl chloride) objects....
Oaki, Yuya; Yagita, Naoki; Imai, Hiroaki
2012-01-02
Iron-oxidizing bacteria produce trivalent iron oxides with the controlled crystal phases outside of their cells. Herein we have synthesized iron oxides with controlled oxidation states and crystal phases through a microbial-mineralization-inspired approach in an aqueous solution at low temperature. Trivalent iron oxides, such as lepidocrocite, ferrihydrite, goethite, and hematite, are selectively obtained from an aqueous solution containing divalent iron ions below 90 °C. The presence of a chelating agent facilitates the control of the oxidation states through the ligand-controlled approach because the precipitation of the divalent iron species is inhibited by the complexation between divalent iron ion and a chelating agent. The control of the crystal phases is achieved by the tuning of the synthetic conditions, such as the initial pH, the concentration of a chelating agent, and the reaction temperature. Furthermore, the resultant iron oxides have hierarchically organized structures consisting of nanoscale objects. The microbial-mineralization-inspired approach by using a chelating agent has potentials for the further morphological control of iron oxides and the further application to aqueous-solution syntheses of other metal oxides. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Dependence of the CaOx and MgOx Growth Rates on Solution Stoichiometry. Non-Kossel Crystal Approach
Chernov, Alexander A.; Rashkovich, L. N.
2005-01-01
Experimental data on step rates on the CaOx and MgOx faces are presented and discussed in terms of non-Kossel crystal growth theory. The theory well describes the major feature - maximum of the growth rate in stoichiometric solution. More precise analyses is needed to fit details of this dependence.
Staples, Hilary
2005-01-01
Biomimicry is an interdisciplinary science in which scientists look for solutions to human needs in nature. It endeavors to discover answers from the molecular, or material level, all the way up to the interrelationships, or systems level. The purpose of this review of the literature is to demonstrate the need and potential application of this new…
A solution-state NMR approach to elucidating pMDI-wood bonding mechanisms in loblolly pine
Daniel Joseph Yelle
2009-01-01
Solution-state NMR spectroscopy is a powerful tool for unambiguously determining the existence or absence of covalent chemical bonds between wood components and adhesives. Finely ground wood cell wall material dissolves in a solvent system containing DMSO-d6 and NMI-d6, keeping wood component polymers intact and in a near-...
Nikolaychuk, Pavel Anatolyevich; Kuvaeva, Alyona Olegovna
2016-01-01
A laboratory experiment on the study of the chemical equilibrium based on the reaction between ferric and iodide ions in solution with the formation of ferrous ions, free iodine, and triiodide ions is developed. The total concentration of iodide and triiodide ions in the reaction mixture during the reaction is determined by the argentometric…
Takahashi, Hideaki; Omi, Atsushi; Morita, Akihiro; Matubayasi, Nobuyuki
2012-06-07
We present a simple and exact numerical approach to compute the free energy contribution δμ in solvation due to the electron density polarization and fluctuation of a quantum-mechanical solute in the quantum-mechanical/molecular-mechanical (QM/MM) simulation combined with the theory of the energy representation (QM/MM-ER). Since the electron density fluctuation is responsible for the many-body QM-MM interactions, the standard version of the energy representation method cannot be applied directly. Instead of decomposing the QM-MM polarization energy into the pairwise additive and non-additive contributions, we take sum of the polarization energies in the QM-MM interaction and adopt it as a new energy coordinate for the method of energy representation. Then, it is demonstrated that the free energy δμ can be exactly formulated in terms of the energy distribution functions for the solution and reference systems with respect to this energy coordinate. The benchmark tests were performed to examine the numerical efficiency of the method with respect to the changes in the individual properties of the solvent and the solute. Explicitly, we computed the solvation free energy of a QM water molecule in ambient and supercritical water, and also the free-energy change associated with the isomerization reaction of glycine from neutral to zwitterionic structure in aqueous solution. In all the systems examined, it was demonstrated that the computed free energy δμ agrees with the experimental value, irrespective of the choice of the reference electron density of the QM solute. The present method was also applied to a prototype reaction of adenosine 5'-triphosphate hydrolysis where the effect of the electron density fluctuation is substantial due to the excess charge. It was demonstrated that the experimental free energy of the reaction has been accurately reproduced with the present approach.
Cai, Chun-Xiang; Xu, Jian; Deng, Nian-Fang; Dong, Xue-Wei; Tang, Hao; Liang, Yu; Fan, Xian-Wei; Li, You-Zhi
2016-11-01
The biomass of filamentous fungi is an important cost-effective biomass for heavy metal biosorption. However, use of free fungal cells can cause difficulties in the separation of biomass from the effluent. In this study, we immobilized the living conidia of the heavy metal-resistant Penicillium janthinillum strain GXCR by polyvinyl alcohol (PVA)-sodium alginate (SA) beads to remove heavy metals from an aqueous solution containing a low concentration (70 mg/L) of Cu, Pb, and Cd. The PVA-SA-conidia beads showed perfect characters of appropriate mechanical strength suitable for metal removal from the dynamic wastewater environment, an ideal settleability, easy separation from the solution, and a high metal biosorption and removal rate even after four cycles of successive sorption-desorption of the beads, overcoming disadvantages when fungal biomasses alone are used for heavy metal removal from wastewater. We also discuss the major biosorption-affecting factors, biosorption models, and biosorption mechanisms.
Senthilkumaar, S.; Krishna, S. K.; Kalaamanic, P.; Subburamaan, C. V.; N. Ganapathy Subramaniam; Kang, T W
2010-01-01
Chemically activated “Waste” Jute Fiber carbon has been effectively used for the removal of five organophosphorous pesticides (malathion, monocrotophos, methylparathion, phosphamidon and dimethoate) from aqueous solutions. The prepared activated jute fiber carbon was characterized by using Elemental analyzer and proximate analysis methods. The adsorption equilibrium was examined at 28 ºC. Three different kinetic models, the pseudo first order, pseudo second order and Elovich kinetic models we...
DEFF Research Database (Denmark)
Montoya-Martinez, Jair; Artes-Rodriguez, Antonio; Pontil, Massimiliano
2014-01-01
We consider the estimation of the Brain Electrical Sources (BES) matrix from noisy electroencephalographic (EEG) measurements, commonly named as the EEG inverse problem. We propose a new method to induce neurophysiological meaningful solutions, which takes into account the smoothness, structured...... matrix and the squared Frobenius norm of the latent source matrix. We develop an alternating optimization algorithm to solve the resulting nonsmooth-nonconvex minimization problem. We analyze the convergence of the optimization procedure, and we compare, under different synthetic scenarios...
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Maria Cristina Carrisi
2016-01-01
Full Text Available A new model for Polyatomic Gases with an arbitrary but fixed number of moments has been recently proposed and investigated in the framework of Extended Thermodynamics; the arbitrariness of the number of moments is linked to a number N and the resulting model is called an N-Model. This model has been elaborated in order to take into account the entropy principle, the Galilean relativity principle, and some symmetry conditions. It has been proved that the solution for all these conditions exists, but it has not been written explicitly because hard notation is necessary; it has only been shown how the theory is self-generating in the sense that if we know the closure of the N-Model, then we will be able to find that of (N+1-Model. Up to now only a single particular solution has been found in this regard. Instead of this, we find here a numberable set of exact solutions which hold for every fixed number N.
Dragan, Oana; Tomuta, Ioan; Casoni, Dorina; Sarbu, Costel; Campian, Radu; Frentiu, Tiberiu
2017-11-16
This article reports for the first time the effects of multiple additives (polyethylene glycol 400, Triton X-100, benzalkonium chloride, and ethyl formate) on the surface tension, pH, and viscosity of 5.25% sodium hypochlorite (NaOCl) irrigant solution. Advanced statistical approaches based on unsupervised multivariate analysis (cluster analysis and principal component analysis) were used to quantify the variability of the physicochemical properties of the modified NaOCl solution for the first time in dentistry. Solutions of 5.25% NaOCl were modified with multiple additives in various concentrations, physicochemical parameters were measured at 22°C and 37°C, and the results were statistically analyzed to group the solutions and reveal the effects of additives. Cluster analysis and principal component analysis revealed that pH and surface tension were the significant parameters (P < .05) for grouping the modified solutions. Four principal components, accounting for 90.6% of the total variance, were associated with flow characteristics (37.3%) determined by polyethylene glycol; the wetting property (22.5% and 10.5%), which was dependent on cationic and nonionic surfactant; and the antimicrobial effect (20.3%) influenced by ethyl formate. Varimax rotation of the principal components showed that the cationic surfactant (benzalkonium chloride) had significantly decreased surface tension compared with the nonionic surfactant (Triton-X). Although ethyl formate was introduced as an odor modifier, it had a significant effect on pH decrease and the occurrence of effervescence with O2 and hypochlorous acid release. The statistical results revealed that the 5.25% NaOCl irrigant solution should be modified with a mixture of 0.1% benzalkonium chloride, 1% ethyl formate, and 7% polyethylene glycol for obtaining a low pH and low surface tension. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Biofuel feedstock production in the United States (US) is an emergent environmental nutrient management issue, whose exploration can benefit from a multi-scale and multimedia systems modeling approach that explicitly addresses diverging stakeholder interests. In the present analy...
Kakolesha, Nyanguila
One focus of this work was to develop of an alternative method to conductivity for determining the acid ionization constants. Computer-controlled osmometry is one of the emerging analytical tools in industrial research and clinical laboratories. It is slowly finding its way into chemistry laboratories. The instrument's microprocessor control ensures shortened data collection time, repeatability, accuracy, and automatic calibration. The equilibrium constants of acetic acid, chloroacetic acid, bromoacetic acid, cyanoacetic acid, and iodoacetic acid have been measured using osmometry and their values compared with the existing literature values obtained, usually, from conductometric measurements. Ionization constant determined by osmometry for the moderately strong weak acids were in reasonably good agreement with literature values. The results showed that two factors, the ionic strength and the osmotic coefficient, exert opposite effects in solutions of such weak acids. Another focus of the work was analytical chemistry students solution preparation skills. The prevailing teacher-structured experiments leave little room for students' ingenuity in quantitative volumetric analysis. The purpose of this part of the study was to improve students' skills in making solutions using instrument feedback in a constructivist-learning model. After making some solutions by weighing and dissolving solutes or by serial dilution, students used the spectrophotometer and the osmometer to compare their solutions with standard solutions. Students perceived the instrument feedback as a nonthreatening approach to monitoring the development of their skill levels and liked to clarify their understanding through interacting with an instructor-observer. An assessment of the instrument feedback and the constructivist model indicated that students would assume responsibility for their own learning if given the opportunity. This study involved 167 students enrolled in Quantitative Chemical
Chaudhury, Sanhita; Bhattacharyya, Arunasis; Goswami, Asok
2014-11-04
The work describes a novel and cleaner approach of electrodriven selective transport of Cs from simulated nuclear waste solutions through cellulose tri acetate (CTA)/poly vinyl chloride (PVC) based polymer inclusion membrane. The electrodriven cation transport together with the use of highly Cs+ selective hexachlorinated derivative of cobalt bis dicarbollide, allows to achieve selective separation of Cs+ from high concentration of Na+ and other fission products in nuclear waste solutions. The transport selectivity has been studied using radiotracer technique as well as atomic emission spectroscopic technique. Transport studies using CTA based membrane have been carried out from neutral solution as well as 0.4 M HNO3, while that with PVC based membrane has been carried out from 3 M HNO3. High decontamination factor for Cs+ over Na+ has been obtained in all the cases. Experiment with simulated high level waste solution shows selective transport of Cs+ from most of other fission products also. Significantly fast Cs+ transport rate along with high selectivity is an interesting feature observed in this membrane. The current efficiency for Cs+ transport has been found to be ∼100%. The promising results show the possibility of using this kind of electrodriven membrane transport methods for nuclear waste treatment.
Brecko, Jonathan; Mathys, Aurore; Dekoninck, Wouter; Leponce, Maurice; VandenSpiegel, Didier; Semal, Patrick
2014-01-01
In this manuscript we present a focus stacking system, composed of commercial photographic equipment. The system is inexpensive compared to high-end commercial focus stacking solutions. We tested this system and compared the results with several different software packages (CombineZP, Auto-Montage, Helicon Focus and Zerene Stacker). We tested our final stacked picture with a picture obtained from two high-end focus stacking solutions: a Leica MZ16A with DFC500 and a Leica Z6APO with DFC290. Zerene Stacker and Helicon Focus both provided satisfactory results. However, Zerene Stacker gives the user more possibilities in terms of control of the software, batch processing and retouching. The outcome of the test on high-end solutions demonstrates that our approach performs better in several ways. The resolution of the tested extended focus pictures is much higher than those from the Leica systems. The flash lighting inside the Ikea closet creates an evenly illuminated picture, without struggling with filters, diffusers, etc. The largest benefit is the price of the set-up which is approximately € 3,000, which is 8 and 10 times less than the LeicaZ6APO and LeicaMZ16A set-up respectively. Overall, this enables institutions to purchase multiple solutions or to start digitising the type collection on a large scale even with a small budget.
Marcus, Hani J; Cundy, Thomas P; Hughes-Hallett, Archie; Yang, Guang-Zhong; Darzi, Ara; Nandi, Dipankar
2014-10-01
The literature reflects a resurgence of interest in endoscopic and keyhole endoscope-assisted neurosurgical approaches as alternatives to conventional microsurgical approaches in carefully selected cases. The aim of this study was to assess the technical challenges of neuroendoscopy, and the scope for technological innovations to overcome these barriers. All full members of the Society of British Neurosurgeons (SBNS) were electronically invited to participate in an online survey. The open-ended structured survey asked three questions; firstly, whether the surgeon presently utilises or has experience with endoscopic or endoscope-assisted approaches; secondly, what they consider to be the major technical barriers to adopting such approaches; and thirdly, what technological advances they foresee improving safety and efficacy in the field. Responses were subjected to a qualitative research method of multi-rater emergent theme analysis. Three clear themes emerged: 1) surgical approach and better integration with image-guidance systems (20%), 2) intra-operative visualisation and improvements in neuroendoscopy (49%), and 3) surgical manipulation and improvements in instruments (74%). The analysis of responses to our open-ended survey revealed that although opinion was varied three major themes could be identified. Emerging technological advances such as augmented reality, high-definition stereo-endoscopy, and robotic joint-wristed instruments may help overcome the technical difficulties associated with neuroendoscopic approaches. Results of this qualitative survey provide consensus amongst the technology end-user community such that unambiguous goals and priorities may be defined. Systems integrating these advances could improve the safety and efficacy of endoscopic and endoscope-assisted neurosurgical approaches.
2000-01-01
for a, 13 C [f, g1] = It is easy to prove the standard fact from linear algebra that a dual basis is indeed a basis. Given a dual basis pair, a...alternative and an algorithmic counterpart of Pedersen’s work [5,6]. These papers deal with algebraic properties of the space of solutions. We continue...such a pair of bases is formed by the Bernstein-B6zier basis, together with the lineal polynomials introduced in the example at the end of the
Directory of Open Access Journals (Sweden)
2009-03-01
Full Text Available We define a special case for the vehicle routing problem with stochastic demands (SC-VRPSD where customer demands are normally distributed. We propose a new linear model for computing the expected length of a tour in SC-VRPSD. The proposed model is based on the integration of the “Traveling Salesman Problem” (TSP and the Assignment Problem. For large-scale problems, we also use an Iterated Local Search (ILS algorithm in order to reach an effective solution.
Luinstra, Gerrit A.; Teuben, Jan H.
1992-01-01
The complexes Cp*2TiR (Cp* = η5-C5Me5; R = Me, Et, n-Pr, C2H3, CH2CMe3, Ph) undergo thermolysis to yield the fulvene complex Cp*FvTi (Fv = η6-C5Me4CH2) and RH. Kinetic measurements and deuterium labeling studies show that the decomposition is catalyzed by Cp*2TiH, which is formed either by
LUINSTRA, GA; TEUBEN, JH
1992-01-01
The complexes Cp*2TiR (Cp* = eta-5-C5Me5; R = Me, Et, n-Pr, C2H3, CH2CMe3, Ph) undergo thermolysis to yield the fulvene complex Cp*FvTi (Fv = eta-6-C5Me4CH2) and RH. Kinetic measurements and deuterium labeling studies show that the decomposition is catalyzed by Cp*2TiH, which is formed either by
Skrzela, Renata; Para, Grazyna; Warszyński, Piotr; Wilk, Kazimiera A
2010-08-19
The interfacial behavior of novel dicephalic cationic surfactants, N,N-bis[3,3'-(trimethylammonio)propyl]alkylamide dibromides and N,N-bis[3,3'-(trimethylammonio)propyl]alkylamide dimethylsulfates, was analyzed both experimentally and theoretically in comparison to their linear standards, 3-[(trimethylammonio)propyl]dodecanamide bromide and 3-[(trimethylammonio)propyl]dodecanamide methylsulfate. Adsorption of the studied double head-single tail surfactants depends strongly upon their structure, making them less surface active in comparison to the single head-single tail structures having the same alkyl chain length. Surface tension isotherms of aqueous solutions of the studied dicephalic derivatives were measured using the pendant drop shape analysis method and interpreted with the so-called surface quasi-two-dimensional electrolyte (STDE) model of ionic surfactant adsorption. The model is based on the assumption that the surfactant ions and counterions (bromide and methylsulfate ions in the studied case) undergo nonequivalent adsorption within the Stern layer, and it allows for accounting for the formation of surfactant ion-counterion associates in the case of multivalent surfactant headgroup ions. As a result, good agreement between theory and experiment was obtained. Additionally, the presence of surfactant-counterion complexes was successfully confirmed by both measurements of the concentration of free bromide ions in solution and molecular modeling simulations. The results of the present study may prove useful in the potential application of the investigated dicephalic cationic surfactants.
Solution phase combinatorial chemistry.
Merritt, A T
1998-06-01
Combinatorial chemistry and parallel array synthesis techniques are now used extensively in the drug discovery process. Although published literature has been dominated by solid phase chemistry approaches, the use of solution phase techniques has also been widely explored. This review considers the advantages and disadvantages of choosing solution phase approaches in the various stages of drug discovery and optimisation, and assesses the practical issues related to these approaches. The uses of standard solution chemistry, the related liquid phase approach, and of supported materials to enhance solution phase chemistry are all illustrated by a comprehensive review of the published literature over the past three years.
Directory of Open Access Journals (Sweden)
V.A. Trofimov
2017-03-01
Full Text Available The article draws attention to the problem of hydrocarbon exploration in deep horizons, which is especially important for the old oil and gas bearing provinces, in particular, for the Volga-Ural province. The example of Riphean-Vendian deposits shows that the solution of this problem is possible if we use not only data of the structural plans of the studied horizons, but also the presence in the immediate vicinity of the identified structures of the oil feeding channels (faults allocated by the high-depth CDP seismic survey. Based on a comparative analysis of the structure of the White Tiger field (Vietnam and Zhigulev arch, it was concluded that they are very similar and that it is expedient to set up, within the last tectonic element, purposeful studies to explore the prospects of oil and gas potential of the Precambrian basement.
Sun, Shuyu
2012-06-02
A new technique for the numerical solution of the partial differential equations governing transport phenomena in porous media is introduced. In this technique, the governing equations as depicted from the physics of the problem are used without extra manipulations. In other words, there is no need to reduce the number of governing equations by some sort of mathematical manipulations. This technique enables the separation of the physics part of the problem and the solver part, which makes coding more robust and could be used in several other applications with little or no modifications (e.g., multi-phase flow in porous media). In this method, one abandons the need to construct the coefficient matrix for the pressure equation. Alternatively, the coefficients are automatically generated within the solver routine. We show examples of using this technique to solving several flow problems in porous media.
Laínez-Aguirre, José Miguel
2015-01-01
Decision making at the enterprise level often encompass not only production operations and product R&D, but other strategic functions such as financial planning and marketing. With the aim of maximizing growth and a firm’s value, companies often focus on co-ordinating these functional components as well as traditional hierarchical decision levels. Understanding this interplay can enhance enterprise capabilities of adaptation and response to uncertainties arising from internal processes as well as the external environment. This book presents concepts, methods, tools and solutions based on mathematical programming, which provides the quantitative support needed for integrated decision-making and ultimately for improving the allocation of overall corporate resources (e.g., materials, cash and personnel). Through a systems perspective, the integrated planning of the supply chain also promotes activities of reuse, reduction and recycling for achieving more sustainable environmental impacts of production/di...
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S. Senthilkumaar
2010-01-01
Full Text Available Chemically activated “Waste” Jute Fiber carbon has been effectively used for the removal of five organophosphorous pesticides (malathion, monocrotophos, methylparathion, phosphamidon and dimethoate from aqueous solutions. The prepared activated jute fiber carbon was characterized by using Elemental analyzer and proximate analysis methods. The adsorption equilibrium was examined at 28 ºC. Three different kinetic models, the pseudo first order, pseudo second order and Elovich kinetic models were selected to analyses the adsorption process. To compare the fitness of pseudo first order and pseudo second order, sum of the squares of the errors and correlation coefficient, r2 values were calculated. The Elovich model was used to confirm the chemisorptions.
Johnston, Peter
2014-03-01
Homology or shared evolutionary origin of jaw adductor muscles in lizards and snakes has been difficult to establish, although snakes clearly arose within the lizard radiation. Lizards typically have temporal adductors layered lateral to medial, and in snakes the muscles are arranged in a rostral to caudal pattern. Recent work has suggested that the jaw adductor group in gnathostomes is arranged as a folded sheet; when this theory is applied to snakes, homology with lizard morphology can be seen. This conclusion revisits the work of S.B. McDowell, J Herpetol 1986; 20:353-407, who proposed that homology involves identity of m. levator anguli oris and the loss of m. adductor mandibulae externus profundus, at least in "advanced" (colubroid) snakes. Here I advance the folded sheet hypothesis across the whole snake tree using new and literature data, and provide a solution to this homology problem. Copyright © 2014 Wiley Periodicals, Inc.
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Y. Sajeev
2015-08-01
Full Text Available The equation-of-motion coupled cluster (EOMCC method based on the excited state Hartree-Fock (ESHF solutions is shown to be appropriate for computing the entire ground state potential energy curves of strongly correlated higher-order bonds. The new approach is best illustrated for the homolytic dissociation of higher-order bonds in molecules. The required multireference character of the true ground state wavefunction is introduced through the linear excitation operator of the EOMCC method. Even at the singles and doubles level of cluster excitation truncation, the nonparallelity error of the ground state potential energy curve from the ESHF based EOMCC method is small.
Zhang, Boce; Luo, Yaguang; Zhou, Bin; Wang, Qin; Millner, Patricia D
2015-08-01
Determination of the minimum free chlorine concentration needed to prevent pathogen survival/cross-contamination during produce washing is essential for the development of science-based food safety regulations and practices. Although the trend of chlorine concentration-contact time on pathogen inactivation is generally understood, specific information on chlorine and the kinetics of pathogen inactivation at less than 1.00 s is urgently needed by the produce processing industry. However, conventional approaches to obtain this critical data have been unable to adequately measure very rapid responses. This paper reports our development, fabrication, and test of a novel microfluidic device, and its application to obtain the necessary data on pathogen inactivation by free chlorine in produce wash solution in times as short as 0.10 s. A novel microfluidic mixer with the capability to accurately determine the reaction time and control the chlorine concentration was designed with three inlets for bacterial, chlorine and dechlorinating solutions, and one outlet for effluent collection. The master mold was fabricated on a silicon wafer with microchannels via photopolymerization. Polydimethylsiloxane replicas with patterned microchannels were prototyped via soft lithography. The replicas were further assembled into the micromixer on glass via O2 plasma treatment, and the inlets were connected to a syringe pump for solution delivery. To determine the kinetics of free chlorine on pathogen inactivation, chlorine solutions of varying concentrations were first pumped into the micromixer, together with the addition of bacterial suspension of Escherichia coli O157:H7 through a separate inlet. This was followed by injection of dechlorinating solution to stop the chlorine-pathogen reaction. The effluent was collected and the surviving bacteria cells were enumerated using a modified 'Most Probable Number' method. Free chlorine concentration was determined using a standard colorimetric
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DAHIYA, P.
2015-05-01
Full Text Available This paper presents the application of hybrid opposition based disruption operator in gravitational search algorithm (DOGSA to solve automatic generation control (AGC problem of four area hydro-thermal-gas interconnected power system. The proposed DOGSA approach combines the advantages of opposition based learning which enhances the speed of convergence and disruption operator which has the ability to further explore and exploit the search space of standard gravitational search algorithm (GSA. The addition of these two concepts to GSA increases its flexibility for solving the complex optimization problems. This paper addresses the design and performance analysis of DOGSA based proportional integral derivative (PID and fractional order proportional integral derivative (FOPID controllers for automatic generation control problem. The proposed approaches are demonstrated by comparing the results with the standard GSA, opposition learning based GSA (OGSA and disruption based GSA (DGSA. The sensitivity analysis is also carried out to study the robustness of DOGSA tuned controllers in order to accommodate variations in operating load conditions, tie-line synchronizing coefficient, time constants of governor and turbine. Further, the approaches are extended to a more realistic power system model by considering the physical constraints such as thermal turbine generation rate constraint, speed governor dead band and time delay.
Roach, Michael D; Williamson, R Scott; Thomas, Joseph A; Griggs, Jason A; Zardiackas, Lyle D
2014-01-01
From the results of laboratory investigations reported in the literature, it has been suggested that stress corrosion cracking (SCC) mechanisms may contribute to early failures in titanium alloys that have elevated oxygen concentrations. However, the susceptibility of titanium alloys to SCC in physiological environments remains unclear. In this study, a fracture mechanics approach was used to examine the SCC susceptibility of CP titanium grade 4 in Ringer's solution and distilled de-ionized (DI) water, at 37°C. The study duration was 26 weeks, simulating the non-union declaration of a plated fracture. Four wedge loads were used corresponding to 86-95% of the alloy's ligament yield load. The longest cracks were measured to be 0.18 mm and 0.10 mm in Ringer's solution and DI water, respectively. SEM analysis revealed no evidence of extensive fluting and quasi-cleavage fracture features which, in literature reports, were attributed to SCC. We thus postulate that the Ringer's solution accelerated the wedge-loaded crack growth without producing the critical stresses needed to change the fracture mechanism. Regression analysis of the crack length results led to a significant best-fit relationship between crack growth velocity (independent variable) and test electrolyte, initial wedge load, and time of immersion of specimen in electrolyte (dependent variables). Copyright © 2013 Wiley Periodicals, Inc.
Improta, Roberto; Scalmani, Giovanni; Frisch, Michael J; Barone, Vincenzo
2007-08-21
A state specific (SS) model for the inclusion of solvent effects in time dependent density functional theory (TD-DFT) computations of emission energies has been developed and coded in the framework of the so called polarizable continuum model (PCM). The new model allows for a rigorous and effective treatment of dynamical solvent effects in the computation of fluorescence and phosphorescence spectra in solution, and it can be used for studying different relaxation time regimes. SS and conventional linear response (LR) models have been compared by computing the emission energies for different benchmark systems (formaldehyde in water and three coumarin derivatives in ethanol). Special attention is given to the influence of dynamical solvation effects on LR geometry optimizations in solution. The results on formaldehyde point out the complementarity of LR and SS approaches and the advantages of the latter model especially for polar solvents and/or weak transitions. The computed emission energies for coumarin derivatives are very close to their experimental counterparts, pointing out the importance of a proper treatment of nonequilibrium solvent effects on both the excited and the ground state energies. The availability of SS-PCM/TD-DFT models for the study of absorption and emission processes allows for a consistent treatment of a number of different spectroscopic properties in solution.
Energy Technology Data Exchange (ETDEWEB)
Minezawa, Noriyuki, E-mail: minezawa@fukui.kyoto-u.ac.jp [Fukui Institute for Fundamental Chemistry, Kyoto University, Sakyo-ku, Kyoto 606-8103 (Japan)
2014-10-28
Examining photochemical processes in solution requires understanding the solvent effects on the potential energy profiles near conical intersections (CIs). For that purpose, the CI point in solution is determined as the crossing between nonequilibrium free energy surfaces. In this work, the nonequilibrium free energy is described using the combined method of linear-response free energy and collinear spin-flip time-dependent density functional theory. The proposed approach reveals the solvent effects on the CI geometries of stilbene in an acetonitrile solution and those of thymine in water. Polar acetonitrile decreases the energy difference between the twisted minimum and twisted-pyramidalized CI of stilbene. For thymine in water, the hydrogen bond formation stabilizes significantly the CI puckered at the carbonyl carbon atom. The result is consistent with the recent simulation showing that the reaction path via this geometry is open in water. Therefore, the present method is a promising way of identifying the free-energy crossing points that play an essential role in photochemistry of solvated molecules.
Jirsák, J.; Škvor, J.
2015-05-01
A simple model and theory of molecular fluids is applied to a binary mixture of water and carbon dioxide. An approach based on the perturbation theory is followed using a reference system of so-called pseudo-hard bodies for water and hard triatomics for carbon dioxide. Pseudo-hard bodies bear the traits of the non-additive nature of association supplementing the common excluded volume effect. The reference term is parametrized using Monte Carlo simulation data on the compressibility factor. After adding a simple mean-field term to the reference equation, fluid phase equilibria are qualitatively reproduced.
An Experimenting Field Approach for the Numerical Solution of Multiphase Flow in Porous Media
Salama, Amgad
2015-07-14
In this work, we apply the experimenting pressure field technique to the problem of the flow of two or more immiscible phases in porous media. In this technique, a set of predefined pressure fields are introduced to the governing partial differential equations. This implies that the velocity vector field and the divergence at each cell of the solution mesh can be determined. However, since none of these fields is the true pressure field entailed by the boundary conditions and/or the source terms, the divergence at each cell will not be the correct one. Rather the residue which is the difference between the true divergence and the calculated one is obtained. These fields are designed such that these residuals are used to construct the matrix of coefficients of the pressure equation and the right-hand side. The experimenting pressure fields are generated in the solver routine and are fed to the different routines, which may be called physics routines, which return to the solver the elements of the matrix of coefficients. Therefore, this methodology separates the solver routines from the physics routines and therefore results in simpler, easy to construct, maintain, and update algorithms.
Zhang, Haimin; Quan, Xie; Chen, Shuo; Zhao, Huimin
2007-11-01
Uniform, large-scale, and well-aligned needle-like ZnO nanorods with good photoluminescence and photocatalysis properties on Zn substrates, have been successfully fabricated using a simple low-temperature seed-layer growth approach in solution (50 °C). The formation of ZnO seed-layer by the anodic oxidation technique (AOT) plays an important role in the subsequent growth of highly oriented ZnO nanorods arrays. Temperature also proved to be a significant factor in the growth of ZnO nanorods and had a great effect on their optical properties. X-ray diffraction (XRD) analysis, selected-area electron diffraction (SAED) pattern and high-resolution TEM (HRTEM) indicated that the needle-like ZnO nanorods were single crystal in nature and that they had grown up preferentially along the [0001] direction. The well-aligned ZnO nanorods arrays on Zn substrates exhibited strong UV emission at around 380 nm at room temperature. To investigate their potential as photocatalysts, degradation of pentachlorophenol (PCP) in aqueous solution was carried out using photocatalytic processes, with comparison to direct photolysis. After 1 h, the degradation efficiencies of PCP by direct photolysis and photocatalytic processes achieved 57% and 76% under given experimental conditions, respectively. This improved degradation efficiency of PCP illustrates that ZnO nanorods arrays on Zn substrates have good photocatalytic activity. This simple low-temperature seed-layer growth approach in solution resulted in the development of an effective and low-cost fabrication process for high-quality ZnO nanorods arrays with good optical and photocatalytic properties that can be applicable in many fields such as photocatalysis, photovoltaic cells, luminescent sensors, and photoconductive sensors.
Ianoş, Robert; Istratie, Roxana; Păcurariu, Cornelia; Lazău, Radu
2016-01-14
The solution combustion synthesis of strontium aluminate, SrAl2O4, via the classic single-fuel approach and the modern fuel-mixture approach was investigated in relation to the synthesis conditions, powder properties and thermodynamic aspects. The single-fuel approach (urea or glycine) did not yield SrAl2O4 directly from the combustion reaction. The absence of SrAl2O4 was explained by the low amount of energy released during the combustion process, in spite of the highly negative values of the standard enthalpy of reaction and standard Gibbs free energy. In the case of single-fuel recipes, the maximum combustion temperatures measured by thermal imaging (482 °C - urea, 941 °C - glycine) were much lower than the calculated adiabatic temperatures (1864 °C - urea, 2147 °C - glycine). The fuel-mixture approach (urea and glycine) clearly represented a better option, since (α,β)-SrAl2O4 resulted directly from the combustion reaction. The maximum combustion temperature measured in the case of a urea and glycine fuel mixture was the highest one (1559 °C), which was relatively close to the calculated adiabatic temperature (1930 °C). The addition of a small amount of flux, such as H3BO3, enabled the formation of pure α-SrAl2O4 directly from the combustion reaction.
Qi, Xiao-Wen; Zhang, Jun-Ling; Zhao, Shu-Ping; Liang, Chang-Yong
2017-10-02
In order to be prepared against potential balance-breaking risks affecting economic development, more and more countries have recognized emergency response solutions evaluation (ERSE) as an indispensable activity in their governance of sustainable development. Traditional multiple criteria group decision making (MCGDM) approaches to ERSE have been facing simultaneous challenging characteristics of decision hesitancy and prioritization relations among assessing criteria, due to the complexity in practical ERSE problems. Therefore, aiming at the special type of ERSE problems that hold the two characteristics, we investigate effective MCGDM approaches by hiring interval-valued dual hesitant fuzzy set (IVDHFS) to comprehensively depict decision hesitancy. To exploit decision information embedded in prioritization relations among criteria, we firstly define an fuzzy entropy measure for IVDHFS so that its derivative decision models can avoid potential information distortion in models based on classic IVDHFS distance measures with subjective supplementing mechanism; further, based on defined entropy measure, we develop two fundamental prioritized operators for IVDHFS by extending Yager's prioritized operators. Furthermore, on the strength of above methods, we construct two hesitant fuzzy MCGDM approaches to tackle complex scenarios with or without known weights for decision makers, respectively. Finally, case studies have been conducted to show effectiveness and practicality of our proposed approaches.
Directory of Open Access Journals (Sweden)
Xiao-Wen Qi
2017-10-01
Full Text Available In order to be prepared against potential balance-breaking risks affecting economic development, more and more countries have recognized emergency response solutions evaluation (ERSE as an indispensable activity in their governance of sustainable development. Traditional multiple criteria group decision making (MCGDM approaches to ERSE have been facing simultaneous challenging characteristics of decision hesitancy and prioritization relations among assessing criteria, due to the complexity in practical ERSE problems. Therefore, aiming at the special type of ERSE problems that hold the two characteristics, we investigate effective MCGDM approaches by hiring interval-valued dual hesitant fuzzy set (IVDHFS to comprehensively depict decision hesitancy. To exploit decision information embedded in prioritization relations among criteria, we firstly define an fuzzy entropy measure for IVDHFS so that its derivative decision models can avoid potential information distortion in models based on classic IVDHFS distance measures with subjective supplementing mechanism; further, based on defined entropy measure, we develop two fundamental prioritized operators for IVDHFS by extending Yager’s prioritized operators. Furthermore, on the strength of above methods, we construct two hesitant fuzzy MCGDM approaches to tackle complex scenarios with or without known weights for decision makers, respectively. Finally, case studies have been conducted to show effectiveness and practicality of our proposed approaches.
Lund, Henrik
2014-01-01
In this new edition of Renewable Energy Systems, globally recognized renewable energy researcher and professor, Henrik Lund, sets forth a straightforward, comprehensive methodology for comparing different energy systems' abilities to integrate fluctuating and intermittent renewable energy sources. The book does this by presenting an energy system analysis methodology and offering a freely available accompanying software tool, EnergyPLAN, which automates and simplifies the calculations supporting such a detailed comparative analysis. The book provides the results of more than fifteen comprehensive energy system analysis studies, examines the large-scale integration of renewable energy into the present system, and presents concrete design examples derived from a dozen renewable energy systems around the globe. Renewable Energy Systems, Second Edition also undertakes the socio-political realities governing the implementation of renewable energy systems by introducing a theoretical framework approach aimed at ...
Directory of Open Access Journals (Sweden)
Patricia Aranda
2012-06-01
Full Text Available Mexican migrant and seasonal farmworkers in the US-Mexico border region face health hazards and occupational risks and are becoming commonly known in the public health literature. According to several studies, farmworkers have high levels of chronic diseases such as diabetes and respiratory problems, are at risk for infectious diseases, and experience among the highest incidences of work-related injuries of any profession.^{ }The findings from two studies are considered and presented with the objective of contributing to an overall understanding of migrant farmworkers as a workforce moving across national boundaries and affected by the work environments and health stressors both shared and unique to each context. We propose a binational approach to comprehensively address the health problems and socioeconomic challenges faced by migrant and seasonal farmworkers. In this paper we present the results of two distinct but complementary studies of farmworker health on the Arizona-Sonora border.
DEFF Research Database (Denmark)
Bozkurt, Hande; Quaglia, Alberto; Gernaey, Krist
The increasing number of alternative wastewater treatment (WWT) technologies and stricter effluent requirements imposed by regulations make the early stage decision making for WWTP layout design, which is currently based on expert decisions and previous experiences, much harder. This paper...... therefore proposes a new approach based on mathematical programming to manage the complexity of the problem and generate/identify novel and optimal WWTP layouts for municipal/domestic wastewater treatment. Towards this end, after developing a database consisting of primary, secondary and tertiary WWT...... solved to obtain the optimal WWT network and the optimal wastewater and sludge flow through the network. The tool is evaluated on a case study, which was chosen as the Benchmark Simulation Model no.1 (BSM1) and many retrofitting options for obtaining a cost-effective treatment were investigated...
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Yelena E. Neupokoeva
2016-01-01
Full Text Available The scientific specification of system and activity approach in relation to conditions of the educational process aimed at the development of computer competence is presented in the article. The task of efficiency increase of training process in information technologies of future teachers of vocational education in area of economy and management is set in the present research. Thus the attention of authors is focused on involving the trainees’ creative potential as much as possible through the application of model of the operated creative process.Results. Research was conducted at the Russian State Vocational Pedagogical University; the main methods of research are a method of supervision, questioning and conversation. By results of research, the specifying steps to areas of technology of the organization of educational process, approaches and techniques are made; didactic materials and manuals that led to increase of results of educational process which main objective is an improvement of quality of formation of computer competence are developed.Scientific novelty. Though separate elements of this research have already appeared in scientific literature, but in such combination, in relation to this technique of the organization of educational process, with use of the user computer hermeneutics (the term is for the first time used in such definition researches have not been conducted yet.Practical significance. The practical importance of work originates in a problem of development of computer competence of future teachers of professional education and plays a key role in the development of continuous education in the conditions of a general computerization and large-scale development of a global network.
Buccioli, Matteo; Agnoletti, Vanni; Padovani, Emanuele; Perger, Peter
2014-01-01
The economic and financial crisis has also had an important impact on the healthcare sector. Available resources have decreased, while at the same time costs as well as demand for healthcare services are on the rise. This coalescing negative impact on availability of healthcare resources is exacerbated even further by a widespread ignorance of management accounting matters. Little knowledge about costs is a strong source of costs augmentation. Although it is broadly recognized that cost accounting has a positive impact on healthcare organizations, it is not widespread adopted. Hospitals are essential components in providing overall healthcare. Operating rooms are critical hospital units not only in patient safety terms but also in expenditure terms. Understanding OR procedures in the hospital provides important information about how health care resources are used. There have been several scientific studies on management accounting in healthcare environments and more than ever there is a need for innovation, particularly by connecting business administration research findings to modern IT tools. IT adoption constitutes one of the most important innovation fields within the healthcare sector, with beneficial effects on the decision making processes. The e-HCM (e-Healthcare Cost Management) project consists of a cost calculation model which is applicable to Business Intelligence. The cost calculation approach comprises elements from both traditional cost accounting and activity-based costing. Direct costs for all surgical procedures can be calculated through a seven step implementation process.
Directory of Open Access Journals (Sweden)
Isabel M. Joao
2017-09-01
Full Text Available Projects thematically focused on simulation and statistical techniques for designing and optimizing chemical processes can be helpful in chemical engineering education in order to meet the needs of engineers. We argue for the relevance of the projects to improve a student centred approach and boost higher order thinking skills. This paper addresses the use of Aspen HYSYS by Portuguese chemical engineering master students to model distillation systems together with statistical experimental design techniques in order to optimize the systems highlighting the value of applying problem specific knowledge, simulation tools and sound statistical techniques. The paper summarizes the work developed by the students in order to model steady-state processes, dynamic processes and optimize the distillation systems emphasizing the benefits of the simulation tools and statistical techniques in helping the students learn how to learn. Students strengthened their domain specific knowledge and became motivated to rethink and improve chemical processes in their future chemical engineering profession. We discuss the main advantages of the methodology from the students’ and teachers perspective
Hird, J. P.; Twilley, R.; Shelden, J.; Carney, J.; Georgiou, I. Y.; Agre, C.
2016-02-01
In response to the Changing Course Design Competition a bold, innovative "systems approach" to link the specific needs of the region's ecosystem, economy and community is proposed. "The Giving Delta" plan empowers the Mississippi River's seasonal natural flood pulse to maximized sediment capture in order to build and maintain wetlands, mitigate the effects of climate change and subsidence, and to slow the inevitable marine transgression of the Delta. Sediment capture is optimized by a series of sediment retention strategies and passive sediment diversion structures, as well as establishing a new deep draft navigation channel connected to the Barataria Bay shoreline littoral zone 40 miles north of the current channel.This paradigm shift from "flood control" to "controlled floods", connects the River's natural flood pulse to the coastal landscape. Using hydraulic residence time in the basin as a design and operational criteria for these controlled and passive structures, balances estuarine recovery and system response tolerance in order to determine the magnitude of the peak flows possible without intolerable salinity suppression in the receiving basins. Seasonal salinity gradients can be established that enable the diversion program to operate in harmony with and promote regional fisheries. On an annual basis, fisheries, communities and ecosystems will adapt to seasonally changing conditions. This plan is not designed to completely rebuild the wetlands that have been lost over the last century. Instead, the design encourages wetland adaptation to accelerated sea level rise in the coastal basins. With this plan, the basin ecologies would "self-organize" in parallel to the human settlement's natural ability to adapt and change to this long-term vision, as a new, consolidated and sustainable Delta emerges. By establishing a framework of implementation over 100 years, incremental adaptation minimizes individual uncertainty and costs within each human generation.
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Pallavi Sharma
2013-12-01
Full Text Available Assembly lines are special flow-line production systems which are of great importance in the industrial production of high quantity standardized commodities. In this article, assembly line balancing problem is formulated as a multi objective (criteria problem where four easily quantifiable objectives (criteria's are defined. Objectives (criteria's included are line efficiency, balance delay, smoothness index, and line time. And the value of these objectives is calculated by five different heuristics. In this paper, focus is made on the prioritization of assembly line balancing (ALB solution methods (heuristics and to select the best of them. For this purpose, a bench mark assembly line balancing problem is solved by five different heuristics and the value of objectives criteria's (performance measures of the line is determined. Finally the prioritization of heuristics is carried out through the use of AHP-TOPSIS based approach by solving an example.
Hall-Aspland, S A; Hall, A P; Rogers, T L
2005-03-01
Mixing models are used to determine diets where the number of prey items are greater than one, however, the limitation of the linear mixing method is the lack of a unique solution when the number of potential sources is greater than the number (n) of isotopic signatures +1. Using the IsoSource program all possible combinations of each source contribution (0-100%) in preselected small increments can be examined and a range of values produced for each sample analysed. We propose the use of a Moore Penrose (M-P) pseudoinverse, which involves the inverse of a 2x2 matrix. This is easily generalized to the case of a single isotope with (p) prey sources and produces a specific solution. The Antarctic leopard seal (Hydrurga leptonyx) was used as a model species to test this method. This seal is an opportunistic predator, which preys on a wide range of species including seals, penguins, fish and krill. The M-P method was used to determine the contribution to diet from each of the four prey types based on blood and fur samples collected over three consecutive austral summers. The advantage of the M-P method was the production of a vector of fractions f for each predator isotopic value, allowing us to identify the relative variation in dietary proportions. Comparison of the calculated fractions from this method with 'means' from IsoSource allowed confidence in the new approach for the case of a single isotope, N.
Novak, A.; Honzik, P.; Bruneau, M.
2017-08-01
Miniaturized vibrating MEMS devices, active (receivers or emitters) or passive devices, and their use for either new applications (hearing, meta-materials, consumer devices,…) or metrological purposes under non-standard conditions, are involved today in several acoustic domains. More in-depth characterisation than the classical ones available until now are needed. In this context, the paper presents analytical and numerical approaches for describing the behaviour of three kinds of planar micro-beams of rectangular shape (suspended rigid or clamped elastic planar beam) loaded by a backing cavity or a fluid-gap, surrounded by very thin slits, and excited by an incident acoustic field. The analytical approach accounts for the coupling between the vibrating structure and the acoustic field in the backing cavity, the thermal and viscous diffusion processes in the boundary layers in the slits and the cavity, the modal behaviour for the vibrating structure, and the non-uniformity of the acoustic field in the backing cavity which is modelled in using an integral formulation with a suitable Green's function. Benchmark solutions are proposed in terms of beam motion (from which the sensitivity, input impedance, and pressure transfer function can be calculated). A numerical implementation (FEM) is handled against which the analytical results are tested.
Solutions to Organizational Paradox
DEFF Research Database (Denmark)
Li, Xin; Worm, Verner; Peihong, Xie
Organizations face all kinds of paradoxical problems. There exist various solutions to organizational paradoxes. We develop a typology that lists nine possible logical approaches to understanding the relationship between paradoxical opposites, out of which we identify five types of solutions...... to organizational paradox. Four of the five solutions are explicitly associated with four prominent philosophies. We show the relevance of the five solutions to the real world by applying our scheme to understand different solutions to the generic strategy paradox. Finally, we address the question whether...
Sun, Chao; Cheng, Chuan Hui; Zhang, Bi Long; Li, Ruo Xuan; Wang, Yuan; Liu, Wei Feng; Luo, Ying Min; Du, Guo Tong; Cong, Shu Lin
2017-11-01
We demonstrate an environment-friendly, simple, and low energy cost approach as an alternative to conventional O2 plasma treatment to modify the surface of indium tin oxide (ITO) anodes for use in organic light-emitting diodes (OLEDs). ITO is electrochemically treated in NaCl aqueous solution. A chlorinated ITO (Cl-ITO) electrode with a work function of 5.41 eV was obtained, which is 0.66 eV higher than that of pre-cleaned ITO. The increase of work function is due to the anodic oxidation reactions occurred on the surface of ITO. The power dissipation is only ∼3 mW in our approach, which is five orders of magnitude lower than that of O2 plasma treatment (∼100 W). We fabricated the OLEDs with the configuration of Cl-ITO/NPB(35 nm)/CBP:Ir(ppy)3 (15 nm, 8 wt%)/TPBi:Ir(ppy)3 (10 nm, 8 wt%)/TPBi (10 nm)/Bphen (50 nm)/Cs2CO3 (2 nm)/Al (100 nm), where NPB is N, Ń-di-1-naphthyl-N, Ń-diphenylbenzidine, CBP is 4‧-bis(carbazol-9-yl)biphenyl, TPBi is 2,2‧,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole), Ir(ppy)3 is bis(3-phenylpyridine) iridium(III) and Bphen is 4,7-diphenyl-1,10-phenanthroline. A maximum power efficiency of 95.0 lm W-1 and external quantum efficiency (EQE) of 24.2% were achieved, respectively, which was slightly higher than that of the OLED fabricated on O2-plasma-treated ITO (91.2 lm W-1, EQE = 23.1%).
Quetchenbach, T. G.; Harper, M. J.; Robinson, J., IV; Hervin, K. K.; Chase, N. A.; Dorji, C.; Jacobson, A. E.
2013-03-01
This letter reports on the design and pilot installation of GridShares, devices intended to alleviate brownouts caused by peak power use on isolated, village-scale mini-grids. A team consisting of the authors and partner organizations designed, built and field-tested GridShares in the village of Rukubji, Bhutan. The GridShare takes an innovative approach to reducing brownouts by using a low cost device that communicates the state of the grid to its users and regulates usage before severe brownouts occur. This demand-side solution encourages users to distribute the use of large appliances more evenly throughout the day, allowing power-limited systems to provide reliable, long-term renewable electricity to these communities. In the summer of 2011, GridShares were installed in every household and business connected to the Rukubji micro-hydro mini-grid, which serves approximately 90 households with a 40 kW nominal capacity micro-hydro system. The installation was accompanied by an extensive education program. Following the installation of the GridShares, the occurrence and average length of severe brownouts, which had been caused primarily by the use of electric cooking appliances during meal preparation, decreased by over 92%. Additionally, the majority of residents surveyed stated that now they are more certain that their rice will cook well and that they would recommend installing GridShares in other villages facing similar problems.
Azadi, Mehdi; Nguyen, Anh V; Yakubov, Gleb E
2015-02-17
Interfacial gas enrichment of dissolved gases (IGE) has been shown to cover hydrophobic solid surfaces in water. The atomic force microscopy (AFM) data has recently been supported by molecular dynamics simulation. It was demonstrated that IGE is responsible for the unexpected stability and large contact angle of gaseous nanobubbles at the hydrophobic solid-water interface. Here we provide further evidence of the significant effect of IGE on an attractive force between hydrophobic solid surfaces in water. The force in the presence of dissolved gas, i.e., in aerated and nonaerated NaCl solutions (up to 4 M), was measured by the AFM colloidal probe technique. The effect of nanobubble bridging on the attractive force was minimized or eliminated by measuring forces on the first approach of the AFM probe toward the flat hydrophobic surface and by using high salt concentrations to reduce gas solubility. Our results confirm the presence of three types of forces, two of which are long-range attractive forces of capillary bridging origin as caused by either surface nanobubbles or gap-induced cavitation. The third type is a short-range attractive force observed in the absence of interfacial nanobubbles that is attributed to the IGE in the form of a dense gas layer (DGL) at hydrophobic surfaces. Such a force was found to increase with increasing gas saturation and to decrease with decreasing gas solubility.
DEFF Research Database (Denmark)
Wegener, Dieter; Finkbeiner, Matthias; Geiger, Dieter
2009-01-01
of overall lifecycle costs as well as energy efficiency and other important environmental issues in the innovation management for industrial solutions. ECP consists of adapted methods for assessing the environmental and financial impacts of industrial solutions (plants, processes, single technologies or even...... complex process technology different hot metal producing technologies (blast furnace route vs. smelting reduction routes COREX / FINEX). The second pilot application is targeted on the assessment of infrastructure solutions especially focusing on the comparison of environmental and financial effects...
Camilli, Fabio; Prados, Emmanuel
2011-01-01
International audience; Viscosity solution is a notion of weak solution for a class of partial differential equations of Hamilton-Jacobi type. The range of applications of the notions of viscosity solution and Hamilton-Jacobi equations is enormous, including common class of partial differential equations such as evolutive problems and problems with boundary conditions, equations arising in optimal control theory, differential games, second-order equations arising in stochastic optimal control...
Höfener, Sebastian; Trumm, Michael; Koke, Carsten; Heuser, Johannes; Ekström, Ulf; Skerencak-Frech, Andrej; Schimmelpfennig, Bernd; Panak, Petra J
2016-03-21
We report a combined computational and experimental study to investigate the UV/vis spectra of 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)pyridine (BTP) ligands in solution. In order to study molecules in solution using theoretical methods, force-field parameters for the ligand-water interaction are adjusted to ab initio quantum chemical calculations. Based on these parameters, molecular dynamics (MD) simulations are carried out from which snapshots are extracted as input to quantum chemical excitation-energy calculations to obtain UV/vis spectra of BTP ligands in solution using time-dependent density functional theory (TDDFT) employing the Tamm-Dancoff approximation (TDA). The range-separated CAM-B3LYP functional is used to avoid large errors for charge-transfer states occurring in the electronic spectra. In order to study environment effects with theoretical methods, the frozen-density embedding scheme is applied. This computational procedure allows to obtain electronic spectra calculated at the (range-separated) DFT level of theory in solution, revealing solvatochromic shifts upon solvation of up to about 0.6 eV. Comparison to experimental data shows a significantly improved agreement compared to vacuum calculations and enables the analysis of relevant excitations for the line shape in solution.
Paduszyński, Kamil
2017-05-17
This paper reports a comprehensive evaluation of the conductor-like screening model for real solvents (COSMO-RS) in predicting infinite dilution activity coefficients (γ(∞)) of molecular solutes in ionic liquids (ILs). In particular, comparative analysis of two quantum chemical levels of calculations used in the COSMO part of COSMO-RS, namely, TZVP-COSMO and TZVPD-FINE, is presented and discussed. The final assessment of the model performance is established based on a comparison of its predictions with the experimental data pool consisting of 41 868 data points extracted form 182 references, covering 233 ILs (including salts belonging to 12 different cationic families) and 150 molecular solutes (including a great variety of non-polar, polar and self-associating organic compounds and water) combined with 8554 distinct binary systems. The impact of the chemical family of both IL and molecular solute on the accuracy of the COSMO-RS predictions is analyzed in terms of both quantitative and qualitative measures. Relevant thermodynamic properties derived from γ(∞), namely, infinite dilution partial excess enthalpy of mixing and infinite dilution selectivity are considered and their values obtained from experimental and COSMO-RS predicted γ(∞) data are confronted. Finally, the impact of the molecular conformation of cations/anions/solutes on the quality of predictions is demonstrated based on some representative systems.
Energy Technology Data Exchange (ETDEWEB)
Xia Chuanhai, E-mail: chuanhaixia@gmail.com [Yantai Institute of Coastal Zone Research for Sustainable Development, CAS, Yantai 264003 (China); Liu Ying; Zhou Shiwei; Yang Cuiyun; Liu Sujing [Yantai Institute of Coastal Zone Research for Sustainable Development, CAS, Yantai 264003 (China); Xu Jie [Dalian Institute of Chemical Physics, CAS, Dalian, 116021 (China); Yu Junbao [Yantai Institute of Coastal Zone Research for Sustainable Development, CAS, Yantai 264003 (China); Chen Jiping; Liang Xinmiao [Dalian Institute of Chemical Physics, CAS, Dalian, 116021 (China)
2009-09-30
Catalytic hydrotreating of chlorophenols was carried out in water with Pd/C at 25 deg. C under atmospheric pressure. 1.0% (w/w) monocholophenols was completely dechlorinated within 60 min. Phenol, cyclohexanone and cyclohexanol were formed. In contrast to the dechlorination of monochlorophenols, the hydrogenation reaction of polychlorinated phenols became difficult and reaction rates were strongly dependent upon the number of the chlorine atoms. The solvent property had a considerably important influence on the dechlorination reaction. Water as a solvent showed more advantages than organic solvents. It was much easier to be hydrodechlorinated for chlorophenols in aqueous solutions. However, the presence of THF, dioxane, DMSO or DMF in water was disadvantageous to the reaction and easily to cause Pd/C deactivation. Additionally, when different halogenated organic compounds were present in aqueous solution, the dehalogenation reaction was the competitive hydrogenation process.
Directory of Open Access Journals (Sweden)
Farzad Amirkhani
2017-03-01
The proposed method is implemented on classical job-shop problems with objective of makespan and results are compared with mixed integer programming model. Moreover, the appropriate dispatching priorities are achieved for dynamic job-shop problem minimizing a multi-objective criteria. The results show that simulation-based optimization are highly capable to capture the main characteristics of the shop and produce optimal/near-optimal solutions with highly credibility degree.
Nishi, Hiroyasu; Nagano, Takahito; Kuwabata, Susumu; Torimoto, Tsukasa
2014-01-14
Cu2ZnSnS4 nanoparticles with sizes of 2-5 nm, synthesized in hot organic solutions, exhibited size-dependent photoelectrochemical properties due to the quantum size effect. The potentials of the valence band edge and conduction band edge of the nanoparticles, experimentally determined by photoelectrochemical measurements, were shifted more positively and more negatively, respectively, with a decrease in particle size.
Directory of Open Access Journals (Sweden)
Hao Yu
2016-12-01
Full Text Available Today, the increased public concern about sustainable development and more stringent environmental regulations have become important driving forces for value recovery from end-of-life and end-of use products through reverse logistics. Waste electrical and electronic equipment (WEEE contains both valuable components that need to be recycled and hazardous substances that have to be properly treated or disposed of, so the design of a reverse logistics system for sustainable treatment of WEEE is of paramount importance. This paper presents a stochastic mixed integer programming model for designing and planning a generic multi-source, multi-echelon, capacitated, and sustainable reverse logistics network for WEEE management under uncertainty. The model takes into account both economic efficiency and environmental impacts in decision-making, and the environmental impacts are evaluated in terms of carbon emissions. A multi-criteria two-stage scenario-based solution method is employed and further developed in this study for generating the optimal solution for the stochastic optimization problem. The proposed model and solution method are validated through a numerical experiment and sensitivity analyses presented later in this paper, and an analysis of the results is also given to provide a deep managerial insight into the application of the proposed stochastic optimization model.
Christov, Ivan C
2012-01-01
In classical continuum physics, a wave is a mechanical disturbance. Whether the disturbance is stationary or traveling and whether it is caused by the motion of atoms and molecules or the vibration of a lattice structure, a wave can be understood as a specific type of solution of an appropriate mathematical equation modeling the underlying physics. Typical models consist of partial differential equations that exhibit certain general properties, e.g., hyperbolicity. This, in turn, leads to the possibility of wave solutions. Various analytical techniques (integral transforms, complex variables, reduction to ordinary differential equations, etc.) are available to find wave solutions of linear partial differential equations. Furthermore, linear hyperbolic equations with higher-order derivatives provide the mathematical underpinning of the phenomenon of dispersion, i.e., the dependence of a wave's phase speed on its wavenumber. For systems of nonlinear first-order hyperbolic equations, there also exists a general ...
DEFF Research Database (Denmark)
Efeoglu, Arkin; Møller, Charles; Serie, Michel
2013-01-01
This paper outlines an artifact building and evaluation proposal. Design Science Research (DSR) studies usually consider encapsulated artifact that have relationships with other artifacts. The solution prototype as a composed artifact demands for a more comprehensive consideration in its systematic...... environment. The solution prototype that is composed from blending product and service prototype has particular impacts on the dualism of DSR’s “Build” and “Evaluate”. Since the mix between product and service prototyping can be varied, there is a demand for a more agile and iterative framework. Van de Ven...
Geoghegan, Michael W
2005-01-01
Podcasting is the art of recording radio show style audio tracks, then distributing them to listeners on the Web via podcasting software such as iPodder. From downloading podcasts to producing a track for fun or profit, ""Podcast Solutions"" covers the entire world of podcasting with insight, humor, and the unmatched wisdom of experience.
Chirskii, V. G.
2017-04-01
The present paper is a survey of a part of the theory devoted to certain problems concerning the algebraic independence of the values of analytic functions, to quantitative results on estimates for the measure of transcendence or the measure of algebraic independence of numbers, to functional analogs of these results on the algebraic independence of solutions of algebraic differential equations, and estimates for the multiplicities of zeros for polynomials in these solutions, which play an important role in the proof of numerical results. This choice is related to the fact that, in December 2016, the head of the Department of Number Theory of Moscow State University, Corresponding Member of the RAS Yu.V. Nesterenko, who did a lot to develop these directions of the theory Transcendental numbers and whose works are marked by many awards, became seventy. He is a laureate of the Markov RAS Prize, 2006, of the Ostrovsky international prize, 1997, of the Hardy-Ramanujan Society Prize, 1997, and the Alexander von Humboldt Prize, 2003. Since the article is dedicated to the 70th anniversary of the birth of Yurii Valentinovich, we preface the scientific part with a brief biography.
Energy Technology Data Exchange (ETDEWEB)
Strom, I.; Joosten, L.; Boonstra, C. [DHV Sustainability Consultants, Eindhoiven (Netherlands)
2006-05-15
PEP stands for 'Promotion of European Passive Houses' and is a consortium of European partners, supported by the European Commission, Directorate General for Energy and Transport. In this working paper an overview is given of Passive House solutions. An inventory has been made of Passive House solutions for new build residences applied in each country. Based on this, the most common basic solutions have been identified and described in further detail, including the extent to which solutions are applied in common and best practice and expected barriers for the implementation in each country. An inventory per country is included in the appendix. The analysis of Passive House solutions in partner countries shows high priority with regard to the performance of the thermal envelope, such as high insulation of walls, roofs, floors and windows/ doors, thermal bridge-free construction and air tightness. Due to the required air tightness, special attention must be paid to indoor air quality through proper ventilation. Finally, efficient ((semi-)solar) heating systems for combined space and DHW heating still require a significant amount of attention in most partner countries. Other basic Passive House solutions show a smaller discrepancy with common practice and fewer barriers have been encountered in partner countries. In the next section, the general barriers in partner countries have been inventoried. For each type of barrier a suggested approach has been given. Most frequently encountered barriers in partner countries are: limited know-how; limited contractor skills; and acceptation of Passive Houses in the market. Based on the suggested approaches to overcoming barriers, this means that a great deal of attention must be paid to providing practical information and solutions to building professionals, providing practical training to installers and contractors and communication about the Passive House concept to the market.
Weatherbee, Andrew; Popov, Ivan; Vitkin, Alex
2017-08-01
The viscosity of turbid colloidal glucose solutions has been accurately determined from spectral domain optical coherence tomography (OCT) M-mode measurements and our recently developed OCT dynamic light scattering model. Results for various glucose concentrations, flow speeds, and flow angles are reported. The relative "combined standard uncertainty" uc(η) on the viscosity measurements was ±1% for the no-flow case and ±5% for the flow cases, a significant improvement in measurement robustness over previously published reports. The available literature data for the viscosity of pure water and our measurements differ by 1% (stagnant case) and 1.5% (flow cases), demonstrating good accuracy; similar agreement is seen across the measured glucose concentration range when compared to interpolated literature values. The developed technique may contribute toward eventual noninvasive glucose measurements in medicine.
Directory of Open Access Journals (Sweden)
W. A. Khan
2012-01-01
Full Text Available The mixed convection of Newtonian fluid flow along a moving horizontal plate with higher-order chemical reaction, variable concentration reactant, and variable wall temperature and concentration is considered. Velocity slip and the thermal convective boundary conditions are applied at the plate surface. The governing partial differential equations are transformed into similarity equations via dimensionless similarity transformations developed by one-parameter continuous group method. The numerical solutions of the transformed ordinary differential equations are constructed for velocity, temperature and concentration functions, the skin friction factor, the rate of heat, and the rate of mass transfer using an implicit finite difference numerical technique. The investigated parameters are buoyancy parameters , , chemical reaction parameter , suction/injection parameter , velocity slip parameter convective heat transfer parameter , magnetic parameter , Prandtl number Pr and Schmidt number, Sc. Comparison with results from the open literature shows a very good agreement.
Pribil, Michael; Ridley, William I.; Emsbo, Poul
2015-01-01
Isotope ratio measurements using a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) commonly use standard-sample bracketing with a single isotope standard for mass bias correction for elements with narrow-range isotope systems measured by MC-ICP-MS, e.g. Cu, Fe, Zn, and Hg. However, sulfur (S) isotopic composition (δ34S) in nature can range from at least − 40 to + 40‰, potentially exceeding the ability of standard-sample bracketing using a single sulfur isotope standard to accurately correct for mass bias. Isotopic fractionation via solution and laser ablation introduction was determined during sulfate sulfur (Ssulfate) isotope measurements. An external isotope calibration curve was constructed using in-house and National Institute of Standards and Technology (NIST) Ssulfate isotope reference materials (RM) in an attempt to correct for the difference. The ability of external isotope correction for Ssulfate isotope measurements was evaluated by analyzing NIST and United States Geological Survey (USGS) Ssulfate isotope reference materials as unknowns. Differences in δ34Ssulfate between standard-sample bracketing and standard-sample bracketing with external isotope correction for sulfate samples ranged from 0.72‰ to 2.35‰ over a δ34S range of 1.40‰ to 21.17‰. No isotopic differences were observed when analyzing Ssulfide reference materials over a δ34Ssulfide range of − 32.1‰ to 17.3‰ and a δ33S range of − 16.5‰ to 8.9‰ via laser ablation (LA)-MC-ICP-MS. Here, we identify a possible plasma induced fractionation for Ssulfate and describe a new method using external isotope calibration corrections using solution and LA-MC-ICP-MS.
Salama, Amgad
2012-06-17
The flow of two immiscible fluids in porous media is ubiquitous particularly in petroleum exploration and extraction. The displacement of one fluid by another immiscible with it represents a very important aspect in what is called enhanced oil recovery. Another example is related to the long-term sequestration of carbon dioxide, CO2 , in deep geologic formations. In this technique, supercritical CO2 is introduced into deep saline aquifer where it displaces the hosting fluid. Furthermore, very important classes of contaminants that are very slightly soluble in water and represent a huge concern if they get introduced to groundwater could basically be assumed immiscible. These are called light non-aqueous phase liquids (LNAPL) and dense non-aqueous phase liquids (DNAPL). All these applications necessitate that efficient algorithms be developed for the numerical solution of these problems. In this work we introduce the use of shifting matrices to numerically solving the problem of two-phase immiscible flows in the subsurface. We implement the cell-center finite difference method which discretizes the governing set of partial differential equations in conservative manner. Unlike traditional solution methodologies, which are based on performing the discretization on a generic cell and solve for all the cells within a loop, in this technique, the cell center information for all the cells are obtained all at once without loops using matrix oriented operations. This technique is significantly faster than the traditional looping algorithms, particularly for larger systems when coding using languages that require repeating interpretation each time a loop is called like Mat Lab, Python and the like. We apply this technique to the transport of LNAPL and DNAPL into a rectangular domain.
Solutions of Nonlocal -Laplacian Equations
Directory of Open Access Journals (Sweden)
Mustafa Avci
2013-01-01
Full Text Available In view of variational approach we discuss a nonlocal problem, that is, a Kirchhoff-type equation involving -Laplace operator. Establishing some suitable conditions, we prove the existence and multiplicity of solutions.
2012-10-01
New Functional Optimization Approach Related to the Sobolev Gradient 5b. GRANT NUMBER Method 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Lederman , C...the Sobolev Gradient Method Carl Lederman and Jean-Luc Cambier Air Force Research Laboratory, Propulsion Directorate Spacecraft Branch (AFRL/RZSS...17] Lederman , C., Vese, L., and Chien, A., “Registration for 3D Morphological Comparison of Brain Aneurysm Growth” Advances in Visual Computing
Mitchell, M.J.; Piatek, K.B.; Christopher, S.; Mayer, B.; Kendall, C.; McHale, P.
2006-01-01
Understanding the effects of climate change including precipitation patterns has important implications for evaluating the biogeochemical responses of watersheds. We focused on four storms in late summer and early fall that occurred after an exceptionally dry period in 2002. We analyzed not only the influence of these storms on episodic chemistry and the role of different water sources in affecting surface water chemistry, but also the relative contributions of these storms to annual biogeochemical mass balances. The study site was a well studied 135-ha watershed in the Adirondack Park of New York State (USA). Our analyses integrated measurements on hydrology, solute chemistry and the isotopic composition of NO 3- (??15N and ??18O) and SO 42- (??34S and ??18O) to evaluate how these storms affected surface water chemistry. Precipitation amounts varied among the storms (Storm 1: Sept. 14-18, 18.5 mm; Storm 2: Sept. 21-24, 33 mm; Storm 3: Sept. 27-29, 42.9 mm; Storm 4: Oct. 16-21, 67.6 mm). Among the four storms, there was an increase in water yields from 2 to 14%. These water yields were much less than in studies of storms in previous years at this same watershed when antecedent moisture conditions were higher. In the current study, early storms resulted in relatively small changes in water chemistry. With progressive storms the changes in water chemistry became more marked with particularly major changes in Cb (sum of base cations), Si, NO 3- , and SO 42- , DOC and pH. Analyses of the relationships between Si, DOC, discharge and water table height clearly indicated that there was a decrease in ground water contributions (i.e., lower Si concentrations and higher DOC concentrations) as the watershed wetness increased with storm succession. The marked changes in chemistry were also reflected in changes in the isotopic composition of SO 42- and NO 3- . There was a strong inverse relationship between SO 42- concentrations and ??34S values suggesting the importance of S
Energy Technology Data Exchange (ETDEWEB)
Gerardi, R.D.; Barnett, N.W. [School of Biological and Chemical Sciences, Deakin University, Geelong (Australia); Jones, P. [Department of Environmental Sciences, University of Plymouth, Plymouth, Devon (United Kingdom)
1999-05-03
Two methods for the chemical generation of the chemiluminescence reagent Ru(bipy){sup 3+}{sub 3} are presented, both of which used lead dioxide as the oxidant with various concentrations of sulphuric acid. The temporal stability of several different Ru(bipy){sup 3+}{sub 3} solutions was investigated, with significant extension to their analytically useful lifetime being afforded by simply increasing the acid concentration. Alternatively, recirculation of the reagent through a glass filter assembly containing lead dioxide also extended the stability of Ru(bipy){sup 3+}{sub 3} under mildly acidic conditions. A series of flow injection analysis experiments, using codeine to generate chemiluminescence, were performed to quantify the stability of the various reagents with the useful lifetimes ranging from several hours to more than a week, depending on the acid concentration. The change in concentration of Ru(bipy){sup 3+}{sub 3} versus time was measured spectrophotometrically (at {lambda}{sub max}, 674 nm) in order to evaluate the kinetics of the reagent degradation process and its effects on chemiluminescence response for codeine. These preliminary results are presented as a simple and robust alternative to electrochemical generation for those applications where medium to long term reagent stability is essential, such as in liquid chromatography and process analysis. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)
Hamid, Sharifah Bee Abdul; Chowdhury, Zaira Zaman; Zain, Sharifuddin Mohammad
2014-04-09
This study examines the feasibility of catalytically pretreated biochar derived from the dried exocarp or fruit peel of mangostene with Group I alkali metal hydroxide (KOH). The pretreated char was activated in the presence of carbon dioxide gas flow at high temperature to upgrade its physiochemical properties for the removal of copper, Cu(II) cations in single solute system. The effect of three independent variables, including temperature, agitation time and concentration, on sorption performance were carried out. Reaction kinetics parameters were determined by using linear regression analysis of the pseudo first, pseudo second, Elovich and intra-particle diffusion models. The regression co-efficient, R² values were best for the pseudo second order kinetic model for all the concentration ranges under investigation. This implied that Cu(II) cations were adsorbed mainly by chemical interactions with the surface active sites of the activated biochar. Langmuir, Freundlich and Temkin isotherm models were used to interpret the equilibrium data at different temperature. Thermodynamic studies revealed that the sorption process was spontaneous and endothermic. The surface area of the activated sample was 367.10 m²/g, whereas before base activation, it was only 1.22 m²/g. The results elucidated that the base pretreatment was efficient enough to yield porous carbon with an enlarged surface area, which can successfully eliminate Cu(II) cations from waste water.
Danish, Mohammed; Khanday, Waheed Ahmad; Hashim, Rokiah; Sulaiman, Nurul Syuhada Binti; Akhtar, Mohammad Nishat; Nizami, Maniruddin
2017-05-01
Box-Behnken model of response surface methodology was used to study the effect of adsorption process parameters for Rhodamine B (RhB) removal from aqueous solution through optimized large surface area date stone activated carbon. The set experiments with three input parameters such as time (10-600min), adsorbent dosage (0.5-10g/L) and temperature (25-50°C) were considered for statistical significance. The adequate relation was found between the input variables and response (removal percentage of RhB) and Fisher values (F- values) along with P-values suggesting the significance of various term coefficients. At an optimum adsorbent dose of 0.53g/L, time 593min and temperature 46.20°C, the adsorption capacity of 210mg/g was attained with maximum desirability. The negative values of Gibb's free energy (ΔG) predicted spontaneity and feasibility of adsorption; whereas, positive Enthalpy change (ΔH) confirmed endothermic adsorption of RhB onto optimized large surface area date stone activated carbons (OLSADS-AC). The adsorption data were found to be the best fit on the Langmuir model supporting monolayer type of adsorption of RhB with maximum monolayer layer adsorption capacity of 196.08mg/g. Copyright © 2017 Elsevier Inc. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Quraishi, M.A., E-mail: maquraishi@rediffmail.com [Department of Applied Chemistry, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India); Singh, Ambrish; Singh, Vinod Kumar [Udai Pratap Autonomous College, Varanasi 221002 (India); Yadav, Dileep Kumar; Singh, Ashish Kumar [Department of Applied Chemistry, Institute of Technology, Banaras Hindu University, Varanasi 221005 (India)
2010-07-01
The inhibition of the corrosion of mild steel in hydrochloric acid and sulphuric acid solutions by the extract of Murraya koenigii leaves has been studied using weight loss, electrochemical impedance spectroscopy (EIS), linear polarization and potentiodynamic polarization techniques. Inhibition was found to increase with increasing concentration of the leaves extract. The effect of temperature, immersion time and acid concentration on the corrosion behavior of mild steel in 1 M HCl and 0.5 M H{sub 2}SO{sub 4} with addition of extract was also studied. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the metal surface. The adsorption of the extract on the mild steel surface obeys the Langmuir adsorption isotherm. The activation energy as well as other thermodynamic parameters (Q, {Delta}H*, and {Delta}S*) for the inhibition process was calculated. These thermodynamic parameters show strong interaction between inhibitor and mild steel surface. The results obtained show that the extract of the leaves of M. koenigii could serve as an effective inhibitor of the corrosion of mild steel in hydrochloric and sulphuric acid media.
Han, Mengzhi; Xu, Ji; Ren, Ying
2017-03-01
Intrinsically disordered proteins (IDPs) are a class of proteins that expected to be largely unstructured under physiological conditions. Due to their heterogeneous nature, experimental characterization of IDP is challenging. Temperature replica exchange molecular dynamics (T-REMD) is a widely used enhanced sampling method to probe structural characteristics of these proteins. However, its application has been hindered due to its tremendous computational cost, especially when simulating large systems in explicit solvent. Two methods, parallel tempering well-tempered ensemble (PT-WTE) and replica exchange with solute tempering (REST), have been proposed to alleviate the computational expense of T-REMD. In this work, we select three different IDP systems to compare the sampling characteristics and efficiencies of the two methods Both the two methods could efficiently sample the conformational space of IDP and yield highly consistent results for all the three IDPs. The efficiencies of the two methods: are compatible, with about 5-6 times better than the plain T-REMD. Besides, the advantages and disadvantages of each method are also discussed. Specially, the PT-WTE method could provide temperature dependent data of the system which could not be achieved by REST, while the REST method could readily be used to a part of the system, which is quite efficient to simulate some biological processes. Copyright © 2016 Elsevier Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
Sharifah Bee Abdul Hamid
2014-04-01
Full Text Available This study examines the feasibility of catalytically pretreated biochar derived from the dried exocarp or fruit peel of mangostene with Group I alkali metal hydroxide (KOH. The pretreated char was activated in the presence of carbon dioxide gas flow at high temperature to upgrade its physiochemical properties for the removal of copper, Cu(II cations in single solute system. The effect of three independent variables, including temperature, agitation time and concentration, on sorption performance were carried out. Reaction kinetics parameters were determined by using linear regression analysis of the pseudo first, pseudo second, Elovich and intra-particle diffusion models. The regression co-efficient, R2 values were best for the pseudo second order kinetic model for all the concentration ranges under investigation. This implied that Cu(II cations were adsorbed mainly by chemical interactions with the surface active sites of the activated biochar. Langmuir, Freundlich and Temkin isotherm models were used to interpret the equilibrium data at different temperature. Thermodynamic studies revealed that the sorption process was spontaneous and endothermic. The surface area of the activated sample was 367.10 m2/g, whereas before base activation, it was only 1.22 m2/g. The results elucidated that the base pretreatment was efficient enough to yield porous carbon with an enlarged surface area, which can successfully eliminate Cu(II cations from waste water.
Hamid, Sharifah Bee Abdul; Chowdhury, Zaira Zaman; Zain, Sharifuddin Mohammad
2014-01-01
This study examines the feasibility of catalytically pretreated biochar derived from the dried exocarp or fruit peel of mangostene with Group I alkali metal hydroxide (KOH). The pretreated char was activated in the presence of carbon dioxide gas flow at high temperature to upgrade its physiochemical properties for the removal of copper, Cu(II) cations in single solute system. The effect of three independent variables, including temperature, agitation time and concentration, on sorption performance were carried out. Reaction kinetics parameters were determined by using linear regression analysis of the pseudo first, pseudo second, Elovich and intra-particle diffusion models. The regression co-efficient, R2 values were best for the pseudo second order kinetic model for all the concentration ranges under investigation. This implied that Cu(II) cations were adsorbed mainly by chemical interactions with the surface active sites of the activated biochar. Langmuir, Freundlich and Temkin isotherm models were used to interpret the equilibrium data at different temperature. Thermodynamic studies revealed that the sorption process was spontaneous and endothermic. The surface area of the activated sample was 367.10 m2/g, whereas before base activation, it was only 1.22 m2/g. The results elucidated that the base pretreatment was efficient enough to yield porous carbon with an enlarged surface area, which can successfully eliminate Cu(II) cations from waste water. PMID:28788595
DEFF Research Database (Denmark)
Chakkol, Mehmet; Johnson, Mark; Raja, Jawwad
2014-01-01
Purpose – This paper aims to adopt service-dominant logic (SDL) to empirically explore network configurations resulting from the provision of goods, goods and services, and solutions. Design/methodology/approach – This paper uses a single, in-depth, exploratory case study in a truck manufacturer...... different value propositions and the resulting network configurations are discussed. In so doing, evidence is provided of a more complex, tetradic network configuration for solutions, with varying degrees of interplay between actors in the flow of operand and operant resources to create value....... and its supply network. An abductive approach is adopted. In total, 54 semi-structured interviews were conducted. Findings – Three value propositions are clearly discernible within the truck provider. These range from a truck to a “solution”. These propositions have different supply network configurations...
Integrated multiphase solutions
Energy Technology Data Exchange (ETDEWEB)
Jiskoot, Mark A. [Jiskoot Autocontrol, Kent (United Kingdom)
1998-07-01
Everyone accepts that multiphase metering provides substantial cost advantages over conventional test separator methods. However the complexity of the flow regimes and process ensures that there is no single applicable technology currently available for all conditions. Numerous optimistic and ill-founded have been made for accuracy. Because of the commercial opportunities, the market is a technology minefield for the potential specifier and user! Jiskoot has introduced an Integarated approach to provision of Multiphase Solutions (IMS) and is the licensee of two distinctly different technologies. This paper outlines a few multiphase measurements problems and the IMS approach using the Mixmeter and Smartstar technologies. (author)
Chang, Sin-Chung
1995-07-01
A new numerical framework for solving conservation laws is being developed. This new framework differs substantially in both concept and methodology from the well-established methods, i.e., finite difference, finite volume, finite element, and spectral methods. It is conceptually simple and designed to overcome several key limitations of the above traditional methods. A two-level scheme for solving the convection-diffusion equation ∂u/∂t + a ∂u/∂x - μ ∂2u/∂x2 = 0 (μ ≥ 0) is constructed and used to illuminate major differences between the present method and those mentioned above. This explicit scheme, referred to as the a-μ scheme, has two independent marching variables unj and (ux)nj which are the numerical analogues of u and ∂u/∂x at (j, n), respectively. The a-μ scheme has the unusual property that its stability is limited only by the CFL condition, i.e., it is independent of μ. Also it can be shown that the amplification factors of the a -μ scheme are identical to those of the Leapfrog scheme if μ = O, and to those of the DuFort-Frankel scheme if a = O. These coincidences are unexpected because the a-μ scheme and the above classical schemes are derived from completely different perspectives, and the a -μ scheme does not reduce to the above classical schemes in the limiting cases. The a-μ scheme is extended to solve the 1D time-dependent Navier-Stokes equations of a perfect gas. Stability of this explicit solver also is limited only by the CFL condition. In spite of the fact that it does not use (i) any techniques related to the high-resolution upwind methods, and (ii) any ad hoc parameter, the current Navier-Stokes solver is capable of generating highly accurate shock tube solutions. Particularly, for high-Reynolds-number flows, shock discontinuities can be resolved within one mesh interval. The inviscid (μ = 0) a-μ scheme is reversible in time. It also is neutrally stable, i.e., free from numerical dissipation. Such a scheme
Mara, Michael W; Shelby, Megan; Stickrath, Andrew; Harpham, Mike; Huang, Jier; Zhang, Xiaoyi; Hoffman, Brian M; Chen, Lin X
2013-11-14
The photodissociation and recombination of CO and 1-methylimidazole (Im) from iron protoporphyrin IX (FePP-ImCO) dissolved in a 30% v/v aqueous solution of Im was studied using ultrafast optical transient absorption (TA) and X-ray transient absorption (XTA) spectroscopies. FePP-ImCO was shown to lose the CO ligand upon excitation at the Q bands, with 3.8 ps vibrational cooling and 21.6 ps intersystem crossing time constants derived from optical TA experiments, followed by ligation of a second Im on the nanosecond time scale. The penta-coordinate FePP-Im intermediate which forms following CO dissociation adopts a square pyramidal geometry with a "domed" iron center that is reminiscent of that formed upon loss of CO from carbonmonoxymyoglobin (MbCO). Unlike MbCO, which typically retains its newly generated penta-coordinated geometry until CO recombination, FePP can adopt a hexa-coordinate geometry by binding an additional Im ligand (FePP-(Im)2), allowing the porphyrin to exist in the low-spin electronic state even without the CO attached. The second Im ligand remains bound until CO recombination occurs with a time constant of 283 μs. The photodissociated states of FePP-ImCO and MbCO 100 ps after photoexcitation have similar iron site geometries, implying that the protein matrix in MbCO maintains minimum potential energy in the heme center despite the large-scale reorganization in the protein secondary and tertiary structure that arises from the dynamic active site/matrix interaction.
Energy Technology Data Exchange (ETDEWEB)
Behpour, M., E-mail: m.behpour@kashanu.ac.ir [Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, I.R. 87317-51167 (Iran, Islamic Republic of); Ghoreishi, S.M.; Khayatkashani, M. [Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, I.R. 87317-51167 (Iran, Islamic Republic of); Soltani, N. [Department of Chemistry, Payame Noor University (PNU), 19395-4697 Tehran (Iran, Islamic Republic of)
2012-01-05
Graphical abstract: Ellagic acid (EA) and tannic acid (TA) were studied as corrosion inhibitors. The electron density HOMO and LUMO of EA and TA were used to explain difference in behavior of them. Highlights: Black-Right-Pointing-Pointer The extract of Punica granatum (PG) and their main constituent (ellagic acid (EA)) are found to be good inhibitors for the corrosion of mild steel in 1 M H{sub 2}SO{sub 4} and 2 M HCl. Black-Right-Pointing-Pointer The electrochemical inhibitive mechanism is explained by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) results. Black-Right-Pointing-Pointer The adsorption of ALLOX on mild steel surface was found to accord with the Temkin adsorption isotherm. Black-Right-Pointing-Pointer The effect of temperature on the corrosion behavior of mild steel in 2 M HCl and 1 M H{sub 2}SO{sub 4} without and with the PG extract was studied. - Abstract: The effect of the extract of Punica granatum (PG) and their main constituents involve ellagic acid (EA) and tannic acid (TA), as mild steel corrosion inhibitor in 2 M HCl and 1 M H{sub 2}SO{sub 4} solutions was investigated by weight loss measurements. The results obtained from the weight loss measurements show that the inhibition efficiency of TA even in high concentration is very low. Thus, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) investigations were used for different concentrations of PG and EA and best concentration of TA. Potentiodynamic polarization curves indicated that PG and EA behave as mixed-type inhibitors. EIS measurements show an increase of the transfer resistance with increasing inhibitor concentration. The temperature effect on the corrosion behavior of steel without and with the PG extract was studied. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm.
Fukuda, Ryoichi; Ehara, Masahiro; Cammi, Roberto
2014-02-01
A perturbative approximation of the state specific polarizable continuum model (PCM) symmetry-adapted cluster-configuration interaction (SAC-CI) method is proposed for efficient calculations of the electronic excitations and absorption spectra of molecules in solutions. This first-order PCM SAC-CI method considers the solvent effects on the energies of excited states up to the first-order with using the zeroth-order wavefunctions. This method can avoid the costly iterative procedure of the self-consistent reaction field calculations. The first-order PCM SAC-CI calculations well reproduce the results obtained by the iterative method for various types of excitations of molecules in polar and nonpolar solvents. The first-order contribution is significant for the excitation energies. The results obtained by the zeroth-order PCM SAC-CI, which considers the fixed ground-state reaction field for the excited-state calculations, are deviated from the results by the iterative method about 0.1 eV, and the zeroth-order PCM SAC-CI cannot predict even the direction of solvent shifts in n-hexane for many cases. The first-order PCM SAC-CI is applied to studying the solvatochromisms of (2,2'-bipyridine)tetracarbonyltungsten [W(CO)4(bpy), bpy = 2,2'-bipyridine] and bis(pentacarbonyltungsten)pyrazine [(OC)5W(pyz)W(CO)5, pyz = pyrazine]. The SAC-CI calculations reveal the detailed character of the excited states and the mechanisms of solvent shifts. The energies of metal to ligand charge transfer states are significantly sensitive to solvents. The first-order PCM SAC-CI well reproduces the observed absorption spectra of the tungsten carbonyl complexes in several solvents.
Ortleb, Sigrun; Seidel, Christian
2017-07-01
In this second symposium at the limits of experimental and numerical methods, recent research is presented on practically relevant problems. Presentations discuss experimental investigation as well as numerical methods with a strong focus on application. In addition, problems are identified which require a hybrid experimental-numerical approach. Topics include fast explicit diffusion applied to a geothermal energy storage tank, noise in experimental measurements of electrical quantities, thermal fluid structure interaction, tensegrity structures, experimental and numerical methods for Chladni figures, optimized construction of hydroelectric power stations, experimental and numerical limits in the investigation of rain-wind induced vibrations as well as the application of exponential integrators in a domain-based IMEX setting.
Vora, Hitesh D; Shanker Rajamure, Ravi; Dahotre, Sanket N; Ho, Yee-Hsien; Banerjee, Rajarshi; Dahotre, Narendra B
2014-09-01
A laser based surface nitriding process was adopted to further enhance the osseo-integration, corrosion resistance, and tribological properties of the commonly used bioimplant alloy, Ti-6Al-4V. Earlier preliminary osteoblast, electrochemical, and corrosive wear studies of laser nitrided titanium in simulated body fluid clearly revealed improvement of cell adhesion as well as enhancement in corrosion and wear resistance but mostly lacked the in-depth fundamental understanding behind these improvements. Therefore, a novel integrated experimental and theoretical approach were implemented to understand the physical phenomena behind the improvements and establish the property-structure-processing correlation of nitrided surface. The first principle and thermodynamic calculations were employed to understand the thermodynamic, electronic, and elastic properties of TiN for enthalpy of formation, Gibbs free energy, density of states, and elastic properties of TiN were investigated. Additionally, open circuit potential and cyclic potentio-dynamic polarization tests were carried out in simulated body fluid to evaluate the corrosion resistance that in turn linked with the experimentally measured and computationally predicted surface energies of TiN. From these results, it is concluded that the enhancement in the corrosion resistance after laser nitriding is mainly attributed to the presence of covalent bonding via hybridization among Ti (p) and N (d) orbitals. Furthermore, mechanical properties, such as, Poisson׳s ratio, stiffness, Pugh׳s ductility criteria, and Vicker׳s hardness, predicted from first principle calculations were also correlated to the increase in wear resistance of TiN. All the above factors together seem to have contributed to significant improvement in both wear and corrosion performance of nitride surface compared to the bare Ti-6Al-4V in physiological environment indicating its suitability for bioimplant applications. Copyright © 2014 Elsevier Ltd. All
Energy Technology Data Exchange (ETDEWEB)
Gupta, Rajat; Chandiwala, Smita (Oxford Brookes Univ., Dept. of Architecture, Headington campus (United Kingdom)). e-mail: rgupta@brookes.ac.uk
2009-07-01
This paper describes the development, application and analysis of an interactive user-friendly Code for Sustainable Homes-based Sustainability Appraisal Toolkit (SAT). SAT runs on MS Excel and is used to evaluate the technical and economical feasibility of achieving Code levels 3, 4, 5 and 6 for a representative sample of new-build dwellings in UK for different scales of development (single-home, 25 homes and 250 homes). The scenarios are modelled using three standard housing types: detached house (104m2), mid-terraced house (79m2) and a low-rise flat (61m2). A range of strategies are evaluated on both demand and supply sides of energy to meet different Code levels. The analysis reveals that if the fabric performance is improved, level 3 and 4 targets can be easily met with minimal low and zero carbon (LZC) technology for detached and mid-terrace houses. The study shows a considerable reduction in additional capital cost per dwelling (ACD) for LZC technologies to meet code level 4, which ranges from GBP 4500 (Euro 4785) for a detached house to GBP 2889 (Euro 3072) for 25 houses. To achieve level 5, ACD is estimated to be GBP 26,000 (Euro 27,645) and GBP 20,000 (Euro 21,265) for a detached and mid-terraced house respectively. Level 6 (zero-carbon) is the most prohibitive and ACD is predicted to be GBP 46,500 (Euro 49,442) for a detached house and around GBP 38,500 (Euro 40,936) for a mid-terraced home. Higher levels of cost savings can be expected for both levels 5 and 6 at community-level strategies. The research shows that it is difficult to achieve the required percentage improvement target in smaller, efficient dwellings such as flats due to the % reduction scale. The research emphasises the importance of maximising energy efficiency improvements to the fabric and form of a dwelling, before adding low/zero carbon systems, and promotes a 'low-energy first and then low-carbon' approach. Also, a mix of energy technologies is required depending upon the
Solute-solute interactions in intermetallic compounds
Energy Technology Data Exchange (ETDEWEB)
Banerjee, Debashis; Murray, Ryan; Collins, Gary S., E-mail: collins@wsu.edu [Washington State University, Department of Physics and Astronomy (United States); Zacate, Matthew O. [Northern Kentucky University, Department of Physics and Geology (United States)
2017-11-15
Experiments were carried out on highly ordered GdAl{sub 2} samples containing extremely dilute mole fractions of{sup 111}In/Cd probe-atom solutes (about 10{sup −11}), intrinsic antisite atoms Al{sub Gd} having mole fractions of order 0-10{sup −2}, and doped with Ag solutes at mole fractions of order 10{sup −2}. Three types of defect interactions were investigated. (1) Quadrupole interactions caused by Ag-solute atoms neighboring{sup 111}In/Cd solute probe atoms were detected using the method of perturbed angular correlation of gamma rays (PAC). Three complexes of pairs of In-probes and Ag-solutes occupying neighboring positions on Gd- and Al-sublattices were identified by comparing site fractions in Gd-poor and Gd-rich GdAl{sub 2}(Ag) samples and from the symmetry of the quadrupole interactions. Interaction enthalpies between solute-atom pairs were determined from temperature dependences of observed site fractions. Repulsive interactions were observed for close-neighbor complexes In{sub Gd}+Ag{sub Gd} and In{sub Gd}+Ag{sub Al} pairs, whereas a slightly attractive interaction was observed for In{sub Al}+Ag{sub Al}. Interaction enthalpies were all small, in the range ±0.15 eV. (2) Quadrupole interactions caused by intrinsic antisite atoms Al{sub Gd} neighboring In{sub Gd} probes were also detected and site fractions measured as a function of temperature, as in previous work on samples not doped with Ag-solutes [Temperature- and composition-driven changes in site occupation of solutes in Gd{sub 1+3x}Al{sub 2−3x}, Zacate and Collins (Phys. Rev. B69, 174202 (1))]. However, the effective binding enthalpy between In{sub Gd} probe and Al{sub Gd} antisite was found to change sign from -0.12 eV (attractive interaction) in undoped samples to + 0.24 eV (repulsive) in Ag-doped samples. This may be attributed to an attractive interaction between Al{sub Gd} antisite atoms and Ag-dopants that competes with the attractive interaction between In{sub Gd} and Al{sub Gd
Alloy solution hardening with solute pairs
Mitchell, John W.
1976-08-24
Solution hardened alloys are formed by using at least two solutes which form associated solute pairs in the solvent metal lattice. Copper containing equal atomic percentages of aluminum and palladium is an example.
Estimating the Cost of Heterogeneous Solutions
Poort, Eltjo; Vliet, Eric van der
2014-01-01
Existing estimation methods have severe limitations when it comes to estimating the delivery cost of heterogeneous IT-based solutions. In this experience report we present Solution-Based Estimation, a new approach that explicitly links a solution's architecture to its delivery cost model.
Omer, Serif; Golden, Eoin; Priebe, Stefan
2016-01-01
Background DIALOG+ is a new intervention to make routine community mental health meetings therapeutically effective. It involves a structured assessment of patient concerns and a solution-focused approach to address them. In a randomised controlled trial, DIALOG+ was associated with better subjective quality of life and other outcomes in patients with psychosis, but it was not clear how this was achieved. This study explored the possible mechanisms. Methods This was a mixed-methods process evaluation within a cluster-randomised controlled trial. Focus groups and interviews were conducted with patients and clinicians who experienced DIALOG+ and were analysed using thematic analysis. The content of DIALOG+ sessions was recorded and analysed according to (i) the type of actions agreed during sessions and (ii) the domains discussed. The subjective quality of life measure was analysed with mixed-effects models to explore whether the effect of DIALOG+ was limited to life domains that had been addressed in sessions or consistent across all domains. Results Four qualitative themes emerged regarding the mechanisms of DIALOG+: (1) a comprehensive structure; (2) self-reflection; (3) therapeutic self-expression; and (4) empowerment. Patients took responsibility for the majority of actions agreed during sessions (65%). The treatment effect on subjective quality of life was largest for living situation (accommodation and people that the patient lives with) and mental health. Two of these domains were among the three most commonly discussed in DIALOG+ sessions (accommodation, mental health, and physical health). Conclusion DIALOG+ initiates positive, domain-specific change in the areas that are addressed in sessions. It provides a comprehensive and solution-focused structure to routine meetings, encourages self-reflection and expression, and empowers patients. Future research should strengthen and monitor these factors. Trial Registration ISRCTN Registry ISRCTN34757603. PMID
Directory of Open Access Journals (Sweden)
Serif Omer
Full Text Available DIALOG+ is a new intervention to make routine community mental health meetings therapeutically effective. It involves a structured assessment of patient concerns and a solution-focused approach to address them. In a randomised controlled trial, DIALOG+ was associated with better subjective quality of life and other outcomes in patients with psychosis, but it was not clear how this was achieved. This study explored the possible mechanisms.This was a mixed-methods process evaluation within a cluster-randomised controlled trial. Focus groups and interviews were conducted with patients and clinicians who experienced DIALOG+ and were analysed using thematic analysis. The content of DIALOG+ sessions was recorded and analysed according to (i the type of actions agreed during sessions and (ii the domains discussed. The subjective quality of life measure was analysed with mixed-effects models to explore whether the effect of DIALOG+ was limited to life domains that had been addressed in sessions or consistent across all domains.Four qualitative themes emerged regarding the mechanisms of DIALOG+: (1 a comprehensive structure; (2 self-reflection; (3 therapeutic self-expression; and (4 empowerment. Patients took responsibility for the majority of actions agreed during sessions (65%. The treatment effect on subjective quality of life was largest for living situation (accommodation and people that the patient lives with and mental health. Two of these domains were among the three most commonly discussed in DIALOG+ sessions (accommodation, mental health, and physical health.DIALOG+ initiates positive, domain-specific change in the areas that are addressed in sessions. It provides a comprehensive and solution-focused structure to routine meetings, encourages self-reflection and expression, and empowers patients. Future research should strengthen and monitor these factors.ISRCTN Registry ISRCTN34757603.
Solute Migration from the Aquifer Matrix into a Solution Conduit and the Reverse.
Li, Guangquan; Field, Malcolm S
2016-09-01
A solution conduit has a permeable wall allowing for water exchange and solute transfer between the conduit and its surrounding aquifer matrix. In this paper, we use Laplace Transform to solve a one-dimensional equation constructed using the Euler approach to describe advective transport of solute in a conduit, a production-value problem. Both nonuniform cross-section of the conduit and nonuniform seepage at the conduit wall are considered in the solution. Physical analysis using the Lagrangian approach and a lumping method is performed to verify the solution. Two-way transfer between conduit water and matrix water is also investigated by using the solution for the production-value problem as a first-order approximation. The approximate solution agrees well with the exact solution if dimensionless travel time in the conduit is an order of magnitude smaller than unity. Our analytical solution is based on the assumption that the spatial and/or temporal heterogeneity in the wall solute flux is the dominant factor in the spreading of spring-breakthrough curves, and conduit dispersion is only a secondary mechanism. Such an approach can lead to the better understanding of water exchange and solute transfer between conduits and aquifer matrix. Euler and Lagrangian approaches are used to solve transport in conduit. Two-way transfer between conduit and matrix is investigated. The solution is applicable to transport in conduit of persisting solute from matrix. © 2016, National Ground Water Association.
Energy Technology Data Exchange (ETDEWEB)
Monferrer, Dominique [IBMB-CSIC, Baldiri Reixach 15, 08028 Barcelona (Spain); Tralau, Tewes [University of Manchester, Faculty of Life Sciences, Manchester Interdisciplinary Biocentre, 131 Princess Street, Manchester M1 7DN (United Kingdom); Kertesz, Michael A. [University of Manchester, Faculty of Life Sciences, Michael Smith Building D1413, Manchester M13 9PT (United Kingdom); Panjikar, Santosh [EMBL Hamburg Outstation, c/o DESY, Notkestrasse 85, D-22603 Hamburg (Germany); Usón, Isabel, E-mail: uson@ibmb.csic.es [ICREA at IBMB-CSIC, Baldiri Reixach 15, 08028 Barcelona (Spain)
2008-08-01
The full-length LysR transcriptional regulator TsaR from C. testosteroni T-2 has been crystallized in two crystal forms and several native and derivative data sets have been collected using synchrotron and in-house X-ray sources. The full-length LysR-type transcriptional regulator TsaR from Comamonas testosteroni T-2 was heterologously overexpressed in Escherichia coli, purified and stabilized under conditions that favoured its rapid crystallization using the microbatch-under-oil technique. The purified protein was highly crystallizable and two different crystal forms were readily obtained. However, only monoclinic crystals gave diffraction beyond 2 Å and there was a slight variation in unit-cell parameters between crystals. The only other LysR-type regulator for which a full-length crystal form is available is CbnR, but no solution could be obtained when this was used as a model in molecular replacement. Mercury and xenon derivatives were therefore produced in order to phase the structure using a MIRAS approach.
Klijn, F.; Slikker, M.; Tijs, S.H.
2000-01-01
In this note we introduce an egalitarian solution, called the dual egalitarian solution, that is the natural counterpart of the egalitarian solution of Dutta and Ray (1989).We prove, among others, that for a convex game the egalitarian solution coincides with the dual egalitarian solution for its
Exact cosmological solutions for MOG
Energy Technology Data Exchange (ETDEWEB)
Roshan, Mahmood [Ferdowsi University of Mashhad, Department of Physics, P.O. Box 1436, Mashhad (Iran, Islamic Republic of)
2015-09-15
We find some new exact cosmological solutions for the covariant scalar-tensor-vector gravity theory, the so-called modified gravity (MOG). The exact solution of the vacuum field equations has been derived. Also, for non-vacuum cases we have found some exact solutions with the aid of the Noether symmetry approach. More specifically, the symmetry vector and also the Noether conserved quantity associated to the point-like Lagrangian of the theory have been found. Also we find the exact form of the generic vector field potential of this theory by considering the behavior of the relevant point-like Lagrangian under the infinitesimal generator of the Noether symmetry. Finally, we discuss the cosmological implications of the solutions. (orig.)
Chen, Qian; Lin, Yao; Tian, Yunfei; Wu, Li; Yang, Lu; Hou, Xiandeng; Zheng, Chengbin
2017-02-07
Sensitive quantification of mercury distribution in fish is challenging because of insufficient sensitivities of conventional analytical methods, the limited mass of organs (tens of micrograms to several milligrams), and dilution of analyte concentration from sample digestion. In this work, a simple and robust approach coupling multiwall carbon nanotubes assisted matrix solid-phase dispersion (MWCNTs-MSPD) to single-drop solution electrode glow discharge-induced cold vapor generation (SD-SEGD-CVG) was developed for the sensitive determination of mercury in limited amount of sample. Mercury species contained in a limited amount of sample can be efficiently extracted into a 100 μL of eluent by MWCNTs-MSPD, which are conveniently converted to Hg(0) by SD-SEGD-CVG and further transported to atomic fluorescence spectrometry for their determination. Therefore, analyte dilution resulted from sample preparation is avoided and sensitivity is significantly improved. On the basis of consumption of 1 mg of sample, a limit of detection of 0.01 μg L(-1) (0.2 pg) was obtained with relative standard deviations (RSDs) of 5.2% and 4.6% for 2 and 20 μg L(-1), respectively. The accuracy of the proposed method was validated by analysis of three Certified Reference Materials with satisfying results. To confirm that SD-SEGD-CVG-AFS coupling to MWCNTs-MSPD is a promising method to quantify mercury distribution in fish, this method was successfully applied for the sensitive determination of mercury in seven organs of common carps (muscle, gill, intestine, liver, gallbladder, brain, and eye) after dietary of mercury species. The proposed method provides advantages of minimum sample dilution, low blank, high sample introduction efficiency, high sensitivity, and minimum toxic chemicals and sample consumption.
Solution-Focused Therapy: Toward the Identification of Therapeutic Tasks.
Molnar, Alex; de Shazer, Steve
1987-01-01
Notes that brief therapy has often been regarded as "problem solving therapy." Discusses development of a solution-focused approach to clinical practice and describes solution-focused therapeutic tasks and interventions. Outlines some of clinical procedures and interventions possible when a solution-focused approach is used. (Author/NB)
Real-Time Ada Problem Solution Study
1989-03-24
Method - Tools Solution Timeframe - Short-term Solution Approach - Remedial Solution 2 - Use a compiler which provides "fast" interrupt procesoing . A...applications will experience timing overhead impacts due to tasking features like task allocation, task activation/ termination , task switching...overhead compared to the processing done within the task itself: 26 Task Normal Description Overhead Proc. (usec) (usec) 1. Task activation and termination
Exact Solutions for Some Fractional Differential Equations
Sonmezoglu, Abdullah
2015-01-01
The extended Jacobi elliptic function expansion method is used for solving fractional differential equations in the sense of Jumarie’s modified Riemann-Liouville derivative. By means of this approach, a few fractional differential equations are successfully solved. As a result, some new Jacobi elliptic function solutions including solitary wave solutions and trigonometric function solutions are established. The proposed method can also be applied to other fractional differential e...
Partnering for A Solution: A Case Study
Jimenez-Smith, Deyrah
2003-01-01
A material-related issue has been identified, which has the potential of impacting the Space Program. Although "in-house" efforts have been underway to solve the problem, a solution has not yet been reached. This presentation shows how a GIDEP member organization is using a Problem Advisory as a solution approach in an effort to receive information from other industry and/or government organizations that may contribute in finding a solution.
Molecular thermodynamics using fluctuation solution theory
DEFF Research Database (Denmark)
Ellegaard, Martin Dela
to relevant experimental data is limited. This thesis addresses the issue of generating and using simple thermodynamic models within a rigorous statistical mechanical framework, the so-called fluctuation solution theory, from which relations connecting properties and phase equilibria can be obtained....... The framework relates thermodynamic variables to molecular pair correlation functions of liquid mixtures. In this thesis, application of the framework is illustrated using two approaches: 1. Solubilities of solid solutes in mixed solvent systems are determined from fluctuation solution theory application...
Periodic Solution of the Hematopoiesis Equation
Directory of Open Access Journals (Sweden)
Ji-Huan He
2013-01-01
Full Text Available Wu and Liu (2012 presented some results for the existence and uniqueness of the periodic solutions for the hematopoiesis model. This paper gives a simple approach to find an approximate period of the model.
Directory of Open Access Journals (Sweden)
Le Tuan Anh
2017-11-01
Full Text Available The title compound, C25H27NO4 (I, the product of the unusual thermolysis of azacyclic allene methyl 10,11-dimethoxy-3,8-dimethyl-6-phenyl-3-azabenzo[d]cyclodeca-4,6,7-triene-5-carboxylate, represents a bicyclic heterosystem and crystallizes in the monoclinic space group P21/c with three crystallographically independent molecules in the unit cell. These independent molecules adopt very similar geometries and differ only in the conformations of the two methoxy substituents on the benzene ring. In two of the three independent molecules, both methoxy groups are almost coplanar with the benzene ring [the C—C—O—Me torsion angles are 10.8 (2, 12.3 (2, 9.1 (2 and 13.6 (3°], whereas in the third molecule, one of the methoxy groups is practically coplanar to and the other methoxy group is roughly perpendicular to the benzene ring, the C—C—O—Me torsion angles being 14.1 (2 and 76.5 (2°. The molecule of (I comprises a fused tetracyclic system containing two five-membered rings (cyclopentenes and two six-membered rings (piperidine and benzene. The five-membered rings have the usual envelope conformation, with the methyl-subsituted C atom as the flap in each molecule, and the six-membered piperidine ring has a chair conformation. The methyl substituent at the N atom occupies the sterically favourable equatorial position. The carboxylate group lies almost within the basal plane of the parent cyclopentene ring [making dihedral angle of 11.68 (8, 18.94 (9 and 15.16 (9° in the three independent molecules], while the phenyl substituent is twisted by 48.26 (6, 42.04 (6 and 41.28 (6° (for the three independent molecules relative to this plane. In the crystal, molecules of (I form stacks along the b-axis direction. The molecules are arranged at van der Waals distances.
Fast, Approximate Solutions for 1D Multicomponent Gas Injection Problems
DEFF Research Database (Denmark)
Jessen, Kristian; Wang, Yun; Ermakov, Pavel
2001-01-01
This paper presents a new approach for constructing approximate analytical solutions for ID, multicomponent gas displacement problems. The solution to mass conservation equations governing ID dispersion-free flow in which components partition between two equilibrium phases is controlled by the ge......This paper presents a new approach for constructing approximate analytical solutions for ID, multicomponent gas displacement problems. The solution to mass conservation equations governing ID dispersion-free flow in which components partition between two equilibrium phases is controlled...
Energy Technology Data Exchange (ETDEWEB)
Barbosa, Diego R.; Silva, Alessandro L. da; Luciano, Edson Jose Rezende; Nepomuceno, Leonardo [Universidade Estadual Paulista (UNESP), Bauru, SP (Brazil). Dept. de Engenharia Eletrica], Emails: diego_eng.eletricista@hotmail.com, alessandrolopessilva@uol.com.br, edson.joserl@uol.com.br, leo@feb.unesp.br
2009-07-01
Problems of DC Optimal Power Flow (OPF) have been solved by various conventional optimization methods. When the modeling of DC OPF involves discontinuous functions or not differentiable, the use of solution methods based on conventional optimization is often not possible because of the difficulty in calculating the gradient vectors at points of discontinuity/non-differentiability of these functions. This paper proposes a method for solving the DC OPF based on Genetic Algorithms (GA) with real coding. The proposed GA has specific genetic operators to improve the quality and viability of the solution. The results are analyzed for an IEEE test system, and its solutions are compared, when possible, with those obtained by a method of interior point primal-dual logarithmic barrier. The results highlight the robustness of the method and feasibility of obtaining the solution to real systems.
Scaling solutions for dilaton quantum gravity
Energy Technology Data Exchange (ETDEWEB)
Henz, T.; Pawlowski, J.M., E-mail: j.pawlowski@thphys.uni-heidelberg.de; Wetterich, C.
2017-06-10
Scaling solutions for the effective action in dilaton quantum gravity are investigated within the functional renormalization group approach. We find numerical solutions that connect ultraviolet and infrared fixed points as the ratio between scalar field and renormalization scale k is varied. In the Einstein frame the quantum effective action corresponding to the scaling solutions becomes independent of k. The field equations derived from this effective action can be used directly for cosmology. Scale symmetry is spontaneously broken by a non-vanishing cosmological value of the scalar field. For the cosmology corresponding to our scaling solutions, inflation arises naturally. The effective cosmological constant becomes dynamical and vanishes asymptotically as time goes to infinity.
Scaling solutions for dilaton quantum gravity
Henz, T.; Pawlowski, J. M.; Wetterich, C.
2017-06-01
Scaling solutions for the effective action in dilaton quantum gravity are investigated within the functional renormalization group approach. We find numerical solutions that connect ultraviolet and infrared fixed points as the ratio between scalar field and renormalization scale k is varied. In the Einstein frame the quantum effective action corresponding to the scaling solutions becomes independent of k. The field equations derived from this effective action can be used directly for cosmology. Scale symmetry is spontaneously broken by a non-vanishing cosmological value of the scalar field. For the cosmology corresponding to our scaling solutions, inflation arises naturally. The effective cosmological constant becomes dynamical and vanishes asymptotically as time goes to infinity.
Exact solution to fractional logistic equation
West, Bruce J.
2015-07-01
The logistic equation is one of the most familiar nonlinear differential equations in the biological and social sciences. Herein we provide an exact solution to an extension of this equation to incorporate memory through the use of fractional derivatives in time. The solution to the fractional logistic equation (FLE) is obtained using the Carleman embedding technique that allows the nonlinear equation to be replaced by an infinite-order set of linear equations, which we then solve exactly. The formal series expansion for the initial value solution of the FLE is shown to be expressed in terms of a series of weighted Mittag-Leffler functions that reduces to the well known analytic solution in the limit where the fractional index for the derivative approaches unity. The numerical integration to the FLE provides an excellent fit to the analytic solution. We propose this approach as a general technique for solving a class of nonlinear fractional differential equations.
National Research Council Canada - National Science Library
White S.A; Goldhill D.R
1997-01-01
As Hartmann's solution is commonly used by anaesthetists, we surveyed a group of Part III FRCA candidates to establish their knowledge of its constituents and the purpose and metabolism of the lactate in solution...
Reconsidering Schwarzschild's original solution
Antoci, S; Liebscher, D. -E.
2001-01-01
We analyse the Schwarzschild solution in the context of the historical development of its present use, and explain the invariant definition of a singular surface at the Schwarzschild's radius, that can be applied to the Kerr-Newman solution too.
Energy Technology Data Exchange (ETDEWEB)
Aftanas, B.L.
1996-04-30
This Functional Design Criteria (FDC) addresses remediation of the plutonium-bearing solutions currently in inventory at the Plutonium Finishing Plant (PFP). The recommendation from the Environmental Impact Statement (EIS) is that the solutions be treated thermally and stabilized as a solid for long term storage. For solutions which are not discardable, the baseline plan is to utilize a denitration process to stabilize the solutions prior to packaging for storage.
Multicapillary mixer of solutions.
Moskowitz, G W; Bowman, R L
1966-07-22
A mixer made from a bundle of glass tubules can mix two solutions within 30 microseconds, with a total-solution flow rate of 1.33 milliliters per second. One solution passes through the interstices of the bundle; the other moves through the lumens of the tubes.
Mobility needs and wireless solutions
DEFF Research Database (Denmark)
Saugstrup, Dan; Henten, Anders
The main purpose of this report is to spell out a methodological approach to the analysis of user needs with respect to mobility. Furthermore, this methodological approach is used in an exemplary analysis of the relationship between user needs and technology solutions offered by different wireless...... technologies. The report is based on a research approach, emphasizing important aspects in relation to developing more user oriented mobile services and applications in a heterogeneous network environment. As a staring point, Scandinavian research within the field of social science concerning mobility...... is described and discussed. Furthermore different wireless technologies are briefly described and discussed in relation to possible transmission capacities and coverage areas. In addition to this, a preliminary framework regarding the implications of mobility on the use and development of mobile services...
Relativity solution for ``Twin paradox'': a comprehensive solution
Sfarti, A.
2012-10-01
We have provided a complete and realistic solution to the problem of Twin Paradox, for the first time, in the frame work of general relativity. Some of the inspiration for this paper has come from the well known papers by Linet and Teyssandier (Phys Rev D 66:024045, 2002) discussing objects moving on geodesics for more general metrics than Schwarzschild. The subject of the "Twin paradox" is encountered frequently in relativity classes but a complete solution in the general relativity framework is not being taught. Our approaches have covered all the cases, starting with inertial motion in flat space time, going through hyperbolic motion in flat space time and ending with the treatment for curved space time.
2016-12-14
Increased weight Monitoring Repair Modify Oligomer Chemistry Reduce backbone polarity Reduction in thermal and mechanical properties Blend/IPN...PA Clearance Number 16586 Effects of Water Uptake on Viscoelastic Properties Dynamic TMA experiments performed at high heating rate (50 °C/min...it greatly reduces saturated moisture content POSS improves wet thermomechanical properties and could prevent shock associated with water release
Coordination of cassava starch to metal ions and thermolysis of ...
African Journals Online (AJOL)
Cassava starch formed Werner-type complexes with ions of metals from the transition groups. This was proven by conductivity and electron paramagnetic resonance measurements. The coordination of starch to central metal ions influenced the thermal decomposition of starch. As a rule complexes started to decompose at ...
Calcium ferrite formation from the thermolysis of calcium tris ...
Indian Academy of Sciences (India)
Various physico-chemical techniques i.e. TG, DTG, DTA, Mössbauer, XRD, IR etc have been used to study the decomposition behaviour from ambient to 900°C and ferrite formation. Three consecutive decomposition steps leading to the formation of -Fe2O3 and calcium carbonate have been observed at various stages of ...
An Effective Approach to Flash Vacuum Thermolytic Studies
DEFF Research Database (Denmark)
Carlsen, Lars; Egsgaard, Helge
1980-01-01
Flash vacuum thermolysis in combination with field ionization mass spectrometry, supplementary with collision activated spectra of the single field ionized molecules, is shown to be a facile and highly informative method for studying even very complex mixtures of primarily formed products...
A Comprehensive Analytical Solution of the Nonlinear Pendulum
Ochs, Karlheinz
2011-01-01
In this paper, an analytical solution for the differential equation of the simple but nonlinear pendulum is derived. This solution is valid for any time and is not limited to any special initial instance or initial values. Moreover, this solution holds if the pendulum swings over or not. The method of approach is based on Jacobi elliptic functions…
Solitary wave solutions to nonlinear evolution equations in ...
Indian Academy of Sciences (India)
This paper obtains solitons as well as other solutions to a few nonlinear evolution equations that appear in various areas of mathematical physics. The two analytical integrators that are applied to extract solutions are tan–cot method and functional variable approaches. The soliton solutions can be used in the further study of ...
Asymptotic behavior of solutions to nonlinear parabolic equation with nonlinear boundary conditions
Directory of Open Access Journals (Sweden)
Diabate Nabongo
2008-01-01
Full Text Available We show that solutions of a nonlinear parabolic equation of second order with nonlinear boundary conditions approach zero as t approaches infinity. Also, under additional assumptions, the solutions behave as a function determined here.
Reddy, Saripally Sudhaker; Sree, Vijaya Gopalan; Cho, Woosum; Jin, Sung-Ho
2016-11-22
Deep-blue fluorescent emitters with Commission Internationale de l'Eclairage (CIE) y≤0.06 are urgently needed for high-density storage, full-color displays and solid-state lighting. However, developing such emitters with high color purity and efficiency in solution-processable non-doped organic light-emitting diodes (OLEDs) remains an important challenge. Here, we present the synthesis of two new deep-blue fluorescent emitters (AFpTPI and AFmTPI) based on 10-(9,9-diethyl-9H-fluoren-2-yl)-9,9-dimethyl-9,10-dihydroacridine as a core and 1,3- and/or 1,4-phenylene-linked triphenylimidazole (TPI) analogues for non-doped solution-processable OLEDs. Their thermal, photophysical, electrochemical, and device characteristics are explored, and also strongly supported by density functional theory (DFT) study. AFpTPI and AFmTPI exhibit excellent thermal stability (≈450 °C) with high glass transition temperatures (Tg ; 141-152 °C) and deep-blue emission with high quantum yields. Specifically, the solution-processed non-doped device with AFpTPI as an emitter exhibits a maximum external quantum efficiency (EQE) of 4.56 % with CIE coordinates of (0.15, 0.06), which exactly matches the European Broadcasting Union (EBU) blue standard. In addition, AFmTPI also displays good efficiency and better color purity (EQE: 3.37 %; CIE (0.15, 0.05)). To the best of our knowledge, the present work is the first report on non-doped solution-processable OLEDs with efficiency close to 5 % and CIE y≤0.06. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Solutions for 80 km DWDM systems
DEFF Research Database (Denmark)
Dochhan, Annika; Griesser, Helmut; Eiselt, Nicklas
2016-01-01
Currently discussed solutions for 80 km DWDM transmission targeting inter-data center connections at 100G and 400G line rates are reviewed. PDM-64QAM, PAM4, and discrete multi-tone transmission (DMT) are investigated, while the focus lies on directly detected solutions. For DMT, the vestigial...... sideband approach significantly increases the tolerance toward chromatic dispersion and bandwidth limitation and gives way to a flexible DWDM 400G transceiver using four to eight wavelengths....
The procedural egalitarian solution
Dietzenbacher, Bas; Borm, Peter; Hendrickx, Ruud
2017-01-01
In this paper we introduce and analyze the procedural egalitarian solution for transferable utility games. This new concept is based on the result of a coalitional bargaining procedure in which egalitarian considerations play a central role. The procedural egalitarian solution is the first
The Procedural Egalitarian Solution
Dietzenbacher, Bas; Borm, Peter; Hendrickx, Ruud
2016-01-01
In this paper we introduce and analyze the procedural egalitarian solution for transferable utility games. This new concept is based on the result of a coalitional bargaining procedure in which egalitarian considerations play a central role. The procedural egalitarian solution is the first
Directory of Open Access Journals (Sweden)
Schaefer Philip W
2002-01-01
Full Text Available Rotationally symmetric solutions are derived for some nonlinear equations of the form in the title in terms of elementary functions. Under suitable assumptions, the nonexistence of entire solutions is also proved for the inequality in the title as well as some radial upper bounds are obtained. These results are the consequence of an appropriate differential inequality.
Cromolyn Sodium Nasal Solution
Cromolyn comes as a solution to use with a special nasal applicator. It usually is inhaled three to six times a day to prevent allergy ... first time, read the instructions provided with the solution. Ask your doctor, pharmacist, or respiratory therapist to ...
White, S A; Goldhill, D R
1997-05-01
As Hartmann's solution is commonly used by anaesthetists, we surveyed a group of Part III FRCA candidates to establish their knowledge of its constituents and the purpose and metabolism of the lactate in solution. Of the 82 candidates surveyed only three (4%) accurately recorded the electrolytes and their concentrations in Hartmann's solution. Lactate was stated to be a source of bicarbonate by 52 (63%) and a source of glucose by 17 (21%). The descriptions of lactate metabolism were largely imprecise, none was complete and 24 (29%) of candidates offered no explanation. The constituents of Hartmann's solution and their concentrations are designed to match those of plasma, reducing ion and fluid shifts postinfusion. The lactate in Hartmann's solution is metabolised by both oxidation and gluconeogenesis, predominantly in the liver, and bicarbonate is generated by both processes over 1-2 h.
Pro SharePoint 2010 Solution Development
Hild, E
2010-01-01
This book takes a practical problem-solution approach to common business challenges. You'll not only encounter interesting code samples, but also see how to combine these examples with the Microsoft collaboration platform's services. The book's solutions focus on using Visual Studio 2008 and its built-in Office development tools to construct the user interface layer. And solutions can interact with SharePoint as a service provider, taking advantage of SharePoint's many collaboration features like document repositories, collaboration sites, and search functions. This book is unique because it s
Topography retrieval using different solutions of the transport intensity equation.
Pinhasi, Shirly V; Alimi, Roger; Perelmutter, Lior; Eliezer, Shalom
2010-10-01
The topography of a phase plate is recovered from the phase reconstruction by solving the transport intensity equation (TIE). The TIE is solved using two different approaches: (a) the classical solution of solving the Poisson differential equation and (b) an algebraic approach with Zernike functions. In this paper we present and compare the topography reconstruction of a phase plate with these solution methods and justify why one solution is preferable over the other.
Stability of Stationary Solutions of the Multifrequency Radiation Diffusion Equations
Energy Technology Data Exchange (ETDEWEB)
Hald, O H; Shestakov, A I
2004-01-20
A nondimensional model of the multifrequency radiation diffusion equation is derived. A single material, ideal gas, equation of state is assumed. Opacities are proportional to the inverse of the cube of the frequency. Inclusion of stimulated emission implies a Wien spectrum for the radiation source function. It is shown that the solutions are uniformly bounded in time and that stationary solutions are stable. The spatially independent solutions are asymptotically stable, while the spatially dependent solutions of the linearized equations approach zero.
Energy Technology Data Exchange (ETDEWEB)
Epple, Mark Dominik
2008-12-03
In this work we examine the Yang-Mills-Schroedinger equation, which is a result from minimizing the vacuum energy density in Coulomb gauge. We use an ansatz for the vacuum wave functional which is motivated by the exact wave functional of quantum electrodynamics. The wave functional is by construction singular on the Gribov horizon and has a variational kernel in the exponent which represents the gluon energy. We derive the so-called Dyson-Schwinger-equations from the variational principle, that the vacuum energy density is stationary under variation with respect to the variational kernel. These Dyson-Schwinger-equations build a set of coupled integral equations for the gluon and ghost propagator, and for the curvature in gauge orbit space. These equations have been derived in the last few years, have been examined analytically in certain approximations, and first numerical results have been obtained. The case of the so-called horizon condition, which means that the ghost form factor is divergent in the infrared, has always been of special interest. But is has been found in certain approximations analytically as well als numerically that the fully coupled system has no self-consistent solution within the employed truncation on two-loop level in the energy. But one can obtain a solvable system by inserting the bare ghost-propagator into the Coulomb equation. This system possesses two different kind of infrared-divergent solutions which differ in the exponents of the power laws of the form factors in the infrared. The weaker divergent solution has previously been found, but not the stronger divergent solution. The subject of this work is to develop a deeper understanding of the presented system. We present a new renormalization scheme which enables us to reduce the number of renormalization parameters by one. This new system of integral equations is solved numerically with greatly increased precision. Doing so we found the stronger divergent solution for the first
Lublinsky, Boris; Yakubovich, Alexey
2013-01-01
The go-to guidebook for deploying Big Data solutions with Hadoop Today's enterprise architects need to understand how the Hadoop frameworks and APIs fit together, and how they can be integrated to deliver real-world solutions. This book is a practical, detailed guide to building and implementing those solutions, with code-level instruction in the popular Wrox tradition. It covers storing data with HDFS and Hbase, processing data with MapReduce, and automating data processing with Oozie. Hadoop security, running Hadoop with Amazon Web Services, best practices, and automating Hadoop processes i
Step Bunching and Solution Flow
Chernov, A. A.
2003-01-01
Imagine a sequence of equidistant steps parallel to one another on a crystal face growing from solution. Steps may be one or part of a lattice spacing high. With such ideal morphology, the most perfect material is expected to be produced. Sometimes this happens. Much more often, however, steps form bunches, acquire wavy shapes and interlace. With time, these spontaneous perturbations may be increased in amplitude, i.e. the stepped surface becomes morphologically unstable. Interferometric studies of Y.G. Kuznetsov, L.N. Rashkovich, P.G. Vekilov and N.A. Booth and the author demonstrated that the step bunching depends at least on direction and rate of solution flow over the interface, supersaturation and presence of impurities. In particular, if solution and step flow are parallel to one another, the steps convene into bunches. If these flows are antiparallel, the bunches disappear. As the step train propagates, the overall bunch height often increases infinitely. However, we have found recently that if the flow rate is large enough, (approximately 1 meter per second), the bunch height may be limited. All these phenomena come from interaction between steps. The interaction mechanisms are still not fully understood. I plan to overview major approaches to the still unresolved problem on how these dissipative structures on growing crystal face appear and evolve.
Supersaturated Electrolyte Solutions: Theory and Experiment
Izmailov, Alexander F.; Myerson, Allan S.; Na, Han-Soo
1995-01-01
Highly supersaturated electrolyte solutions can be prepared and studied employing an electrodynamic levitator trap (ELT) technique. The ELT technique involves containerless suspension of a microdroplet thus eliminating dust, dirt, and container walls which normally cause heterogeneous nucleation. This allows very high supersaturations to be achieved. A theoretical study of the experimental results obtained for the water activity in microdroplets of various electrolyte solutions is based on the development of the Cahn-Hilliard formalism for electrolyte solutions. In the approach suggested the metastable state for electrolyte solutions is described in terms of the conserved order parameter omega(r,t) associated with fluctuations of the mean solute concentration n(sub 0). Parameters of the corresponding Ginzburg-Landau free energy functional which defines the dynamics of metastable state relaxation are determined and expressed through the experimentally measured quantities. A correspondence of 96-99 % between theory and experiment for all solutions studied was achieved and allowed the determination of an analytical expression for the spinodal concentration n(sub spin), and its calculation for various electrolyte solutions at 298 K. The assumption that subcritical solute clusters consist of the electrically neutral Bjerrum pairs has allowed both analytical and numerical investigation of the number-size N(sub c) of nucleation monomers (aggregates of the Bjerrum pairs) which are elementary units of the solute critical clusters. This has also allowed estimations for the surface tension Alpha, and equilibrium bulk energy Beta per solute molecule in the nucleation monomers. The dependence of these properties on the temperature T and on the solute concentration n(sub 0) through the entire metastable zone (from saturation concentration n(sub sat) to spinodal n(sub spin) is examined. It has been demonstrated that there are the following asymptotics: N(sub c), = I at spinodal
Nanocomposites Based on Metal and Metal Sulfide Clusters Embedded in Polystyrene
Directory of Open Access Journals (Sweden)
Gianfranco Carotenuto
2011-08-01
Full Text Available Transition-metal alkane-thiolates (i.e., organic salts with formula Me(SRx, where R is a linear aliphatic hydrocarbon group, –CnH2n+1 undergo a thermolysis reaction at moderately low temperatures (close to 200 °C, which produces metal atoms or metal sulfide species and an organic by-product, disulfide (RSSR or thioether (RSR molecules, respectively. Alkane-thiolates are non-polar chemical compounds that dissolve in most techno-polymers and the resulting solid solutions can be annealed to generate polymer-embedded metal or metal sulfide clusters. Here, the preparation of silver and gold clusters embedded into amorphous polystyrene by thermolysis of a dodecyl-thiolate precursor is described in detail. However, this chemical approach is quite universal and a large variety of polymer-embedded metals or metal sulfides could be similarly prepared.
Convergent Aeronautics Solutions Project
National Aeronautics and Space Administration — The Convergent Aeronautics Solutions (CAS) Project uses short-duration activities to establish early-stage concept and technology feasibility for high-potential...
Directory of Open Access Journals (Sweden)
TUTUNEA MIHAELA FILOFTEIA
2012-09-01
Full Text Available The integration of activities, the business processes as well as their optimization, bring the perspective of profitable growth and create significant and competitive advantages in any company. The adoption of some ERP integrated software solutions, from SMEs’ perspective, must be considered as a very important management decision in medium and long term. ERP solutions, along with the transparent and optimized management of all internal processes, also offer an intra and inter companies collaborative platform, which allows a rapid expansion of activities towards e- business and mobile-business environments. This material introduces ERP solutions for SMEs from commercial offer and open source perspective; the results of comparative analysis of the solutions on the specific market, can be an useful aid to the management of the companies, in making the decision to integrate business processes, using ERP as a support.
The Conductivity of Solutions.
Rayner-Canham, Geoff
1993-01-01
Presents historical background and modern explanations for the popular demonstration of showing conductivity of solutions through the insertion of a light-bulb conductivity tester into deionized water and water with salt in it. (PR)
Piezoelectric Energy Harvesting Solutions
Caliò, Renato; Rongala, Udaya Bhaskar; Camboni, Domenico; Milazzo, Mario; Stefanini, Cesare; de Petris, Gianluca; Oddo, Calogero Maria
2014-01-01
This paper reviews the state of the art in piezoelectric energy harvesting. It presents the basics of piezoelectricity and discusses materials choice. The work places emphasis on material operating modes and device configurations, from resonant to non-resonant devices and also to rotational solutions. The reviewed literature is compared based on power density and bandwidth. Lastly, the question of power conversion is addressed by reviewing various circuit solutions. PMID:24618725
Piezoelectric Energy Harvesting Solutions
Directory of Open Access Journals (Sweden)
Renato Caliò
2014-03-01
Full Text Available This paper reviews the state of the art in piezoelectric energy harvesting. It presents the basics of piezoelectricity and discusses materials choice. The work places emphasis on material operating modes and device configurations, from resonant to non-resonant devices and also to rotational solutions. The reviewed literature is compared based on power density and bandwidth. Lastly, the question of power conversion is addressed by reviewing various circuit solutions.
Piezoelectric energy harvesting solutions.
Caliò, Renato; Rongala, Udaya Bhaskar; Camboni, Domenico; Milazzo, Mario; Stefanini, Cesare; de Petris, Gianluca; Oddo, Calogero Maria
2014-03-10
This paper reviews the state of the art in piezoelectric energy harvesting. It presents the basics of piezoelectricity and discusses materials choice. The work places emphasis on material operating modes and device configurations, from resonant to non-resonant devices and also to rotational solutions. The reviewed literature is compared based on power density and bandwidth. Lastly, the question of power conversion is addressed by reviewing various circuit solutions.
Energy Technology Data Exchange (ETDEWEB)
NONE
2010-01-15
The contribution under consideration reports on the need of action and on solution attempts for an accelerated establishment of natural gas and bio methane in the future fuel mix. The authors come to the following conclusions: The energy situation and climatic situation require a stronger diversification of fuels and drives. The targets for the amount of natural gas and bio methane as a fuel are not reached yet. The characteristics of natural gas speak for an accelerated establishment in the traffic sector. The admixture of bio methane can increase the climatic, environmental and resources advantages. In order to penetrate the market all participants involved must commit themselves to a concrete 'roadmap'. The contribution shows which measures must be converted by the participants involved in order to be able to utilize fully the potentials of the employment of natural gas and bio methane in the traffic sector.
General Solutions to Functional and Kinematic Redundancy
Directory of Open Access Journals (Sweden)
Pål J. From
2008-04-01
Full Text Available A systematic and general approach to represent functional redundancy is presented. It is shown how this approach allows the freedom provided by functional redundancy to be integrated into the inverse geometric problem for real-time applications and how it can be utilised to improve performance. A set of new iterative solutions to the inverse geometric problem, well suited for kinematically redundant manipulators, is also presented.
Taxonomy of Cross-Platform Mobile Applications Development Approaches
Wafaa S. El-Kassas; Bassem A. Abdullah; Ahmed H. Yousef; Ayman M. Wahba
2017-01-01
The developers use the cross-platform mobile development solutions to develop the mobile application once and run it on many platforms. Many of these cross-platform solutions are still under research and development. Also, these solutions are based on different approaches such as Cross-Compilation approach, Virtual Machine approach, and Web-Based approach. There are many survey papers about the cross-platform mobile development solutions but they do not include the most recent approaches, inc...
Mean-field learning for satisfactory solutions
Tembine, Hamidou
2013-12-01
One of the fundamental challenges in distributed interactive systems is to design efficient, accurate, and fair solutions. In such systems, a satisfactory solution is an innovative approach that aims to provide all players with a satisfactory payoff anytime and anywhere. In this paper we study fully distributed learning schemes for satisfactory solutions in games with continuous action space. Considering games where the payoff function depends only on own-action and an aggregate term, we show that the complexity of learning systems can be significantly reduced, leading to the so-called mean-field learning. We provide sufficient conditions for convergence to a satisfactory solution and we give explicit convergence time bounds. Then, several acceleration techniques are used in order to improve the convergence rate. We illustrate numerically the proposed mean-field learning schemes for quality-of-service management in communication networks. © 2013 IEEE.
Li, Xianghong; Deng, Shuduan; Fu, Hui; Mu, Guannan; Zhao, Ning
2008-06-01
The synergism between rare earth cerium(IV) ion and vanillin (4-hydroxy-3-methoxy-benzaldehyde) on the corrosion of cold rolled steel (CRS) in 1.0 M H 2SO 4 solution at five temperatures ranging from 20 to 60 °C was first studied by weight loss and potentiodynamic polarization methods. The inhibited solutions were analyzed by ultraviolet and visible spectrophotometer (UV-vis). The adsorbed film of CRS surface containing optimum doses of the blends Ce 4+-vanillin was investigated by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). The results revealed that vanillin had a moderate inhibitive effect, and the inhibition efficiency (IE) increased with the vanillin concentration. The adsorption of vanillin obeyed Temkin adsorption isotherm. Polarization curves showed that vanillin was a mixed-type inhibitor in sulfuric acid, while prominently inhibited the cathodic reaction. For the cerium(IV) ion, it had a negligible effect, and the maximum IE was only about 20%. However, incorporation of Ce 4+ with vanillin improved significantly the inhibition performance. The IE for Ce 4+ in combination with vanillin was higher than the summation of IE for single Ce 4+ and single vanillin, which was synergism in nature. A high inhibition efficiency, 98% was obtained by a mixture of 25-200 mg l -1 vanillin and 300-475 mg l -1 Ce 4+. UV-vis showed that the new complex of Ce 4+-vanillin was formed in 1.0 M H 2SO 4 for Ce 4+ combination with vanillin. Polarization studies showed that the complex of Ce 4+-vanillin acted as a mixed-type inhibitor, which drastically inhibits both anodic and cathodic reactions. FTIR and XPS revealed that a protective film formed in the presence of both vanillin and Ce 4+ was composed of cerium oxide and the complex of Ce 4+-vanillin. The synergism between Ce 4+ and vanillin could also be evidenced by AFM images. Depending on the results, the synergism mechanism was discussed from the
Energy Technology Data Exchange (ETDEWEB)
Li Xianghong [Department of Fundamental Courses, Southwest Forestry University, Kunming 650224 (China)], E-mail: xianghong-li@163.com; Deng Shuduan [Department of Wood Science and Technology, Southwest Forestry University, Kunming 650224 (China); Fu Hui [Department of Fundamental Courses, Southwest Forestry University, Kunming 650224 (China); Mu Guannan [Department of Chemistry, Yunnan University, Kunming 650091 (China); Zhao Ning [Department of Fundamental Courses, Southwest Forestry University, Kunming 650224 (China)
2008-06-30
The synergism between rare earth cerium(IV) ion and vanillin (4-hydroxy-3-methoxy-benzaldehyde) on the corrosion of cold rolled steel (CRS) in 1.0 M H{sub 2}SO{sub 4} solution at five temperatures ranging from 20 to 60 deg. C was first studied by weight loss and potentiodynamic polarization methods. The inhibited solutions were analyzed by ultraviolet and visible spectrophotometer (UV-vis). The adsorbed film of CRS surface containing optimum doses of the blends Ce{sup 4+}-vanillin was investigated by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). The results revealed that vanillin had a moderate inhibitive effect, and the inhibition efficiency (IE) increased with the vanillin concentration. The adsorption of vanillin obeyed Temkin adsorption isotherm. Polarization curves showed that vanillin was a mixed-type inhibitor in sulfuric acid, while prominently inhibited the cathodic reaction. For the cerium(IV) ion, it had a negligible effect, and the maximum IE was only about 20%. However, incorporation of Ce{sup 4+} with vanillin improved significantly the inhibition performance. The IE for Ce{sup 4+} in combination with vanillin was higher than the summation of IE for single Ce{sup 4+} and single vanillin, which was synergism in nature. A high inhibition efficiency, 98% was obtained by a mixture of 25-200 mg l{sup -1} vanillin and 300-475 mg l{sup -1} Ce{sup 4+}. UV-vis showed that the new complex of Ce{sup 4+}-vanillin was formed in 1.0 M H{sub 2}SO{sub 4} for Ce{sup 4+} combination with vanillin. Polarization studies showed that the complex of Ce{sup 4+}-vanillin acted as a mixed-type inhibitor, which drastically inhibits both anodic and cathodic reactions. FTIR and XPS revealed that a protective film formed in the presence of both vanillin and Ce{sup 4+} was composed of cerium oxide and the complex of Ce{sup 4+}-vanillin. The synergism between Ce{sup 4+} and vanillin could also be evidenced
Bai, Tianyu
2014-01-01
A facile solution-phase route for the preparation of AgInSe2 nanocrystals was developed by using silver nitrate, indium stearate, and oleylamine-selenium (OAm-Se) as precursors. The evolution process of the AgInSe2 nanocrystals is discussed in detail and different reaction conditions all have a great impact on the growth and morphology of the nanocrystals. Alloyed AgIn(S1-xSex)2 nanocrystals with controlled composition across the entire range (0 ≤ x ≤ 1) was also successfully prepared by modulating the S/Se reactant mole ratio. X-ray diffraction (XRD), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) were used to confirm that the alloyed AgIn(S1-xSex)2 nanocrystals are homogeneous. The UV-vis absorption spectra revealed that the band gap energies of the alloyed AgIn(S1-xSex)2 nanocrystals could be continuously tuned by increasing the Se content. © The Royal Society of Chemistry 2014.
Effects of organic solutes properties on the volatilization processes from water solutions.
Lee, Chung-Kung; Chao, Huan-Ping; Lee, Jiunn-Fwu
2004-01-01
Effects of organic solutes properties, including Henry's law constant (H), molecular weight (M), molar volume at normal boiling point (Vb), and solubility (S), on the usefulness of rate estimation by reference to a reference substance (i.e., reference substance concept) and on the evaporation rate were investigated by measuring the volatilization rate constant of organic solutes under different environmental conditions, including mixing and surfactants. It was found that if benzene was used as a reference substance, the ratio of the solute rate to that of benzene (F) becomes insensitive to water mixing, whether the solute possessed high or low Henry's law constant. In the presence of surfactants, however, the F value changes sharply as the solute solubility decreases. For benzene, toluene, ethylbenzene, and xylenes (BTEX), the F values are essentially constant irrespective of the presence of other chemicals (including organic compounds, surfactants, and salinity) and of the variation in temperature. On the other hand, the volatilization rates are closely related to molecular weight (solubility) in the existence of mixing (surfactants). Three different approaches, i.e., mass-transport theory, modified Knudsen equation, and reaction rate concept, were used to evaluate the dependence of solute volatilization rates on solute properties. It was concluded that the interaction between solute properties and environmental parameters might play a key role in the volatilization process of organic solutes under different environmental conditions.
Deconstructing graphite: graphenide solutions.
Pénicaud, Alain; Drummond, Carlos
2013-01-15
Growing interest in graphene over past few years has prompted researchers to find new routes for producing this material other than mechanical exfoliation or growth from silicon carbide. Chemical vapor deposition on metallic substrates now allows researchers to produce continuous graphene films over large areas. In parallel, researchers will need liquid, large scale, formulations of graphene to produce functional graphene materials that take advantage of graphene's mechanical, electrical, and barrier properties. In this Account, we describe methods for creating graphene solutions from graphite. Graphite provides a cheap source of carbon, but graphite is insoluble. With extensive sonication, it can be dispersed in organic solvents or water with adequate additives. Nevertheless, this process usually creates cracks and defects in the graphite. On the other hand, graphite intercalation compounds (GICs) provide a means to dissolve rather than disperse graphite. GICS can be obtained through the reaction of alkali metals with graphite. These compounds are a source of graphenide salts and also serve as an excellent electronic model of graphene due to the decoupling between graphene layers. The graphenide macroions, negatively charged graphene sheets, form supple two-dimensional polyelectrolytes that spontaneously dissolve in some organic solvents. The entropic gain from the dissolution of counterions and the increased degrees of freedom of graphene in solution drives this process. Notably, we can obtain graphenide solutions in easily processable solvents with low boiling points such as tetrahydrofuran or cyclopentylmethylether. We performed a statistical analysis of high resolution transmission electronic micrographs of graphene sheets deposited on grids from GICs solution to show that the dissolved material has been fully exfoliated. The thickness distribution peaks with single layers and includes a few double- or triple-layer objects. Light scattering analysis of the
Jorgensen, Adam; Welch, John; Clark, Dan; Price, Christopher; Mitchell, Brian
2014-01-01
Tap the power of Big Data with Microsoft technologies Big Data is here, and Microsoft's new Big Data platform is a valuable tool to help your company get the very most out of it. This timely book shows you how to use HDInsight along with HortonWorks Data Platform for Windows to store, manage, analyze, and share Big Data throughout the enterprise. Focusing primarily on Microsoft and HortonWorks technologies but also covering open source tools, Microsoft Big Data Solutions explains best practices, covers on-premises and cloud-based solutions, and features valuable case studies. Best of all,
Calculus problems and solutions
Ginzburg, Abraham
2011-01-01
Ideal for self-instruction as well as for classroom use, this text helps students improve their understanding and problem-solving skills in analysis, analytic geometry, and higher algebra. More than 1,200 problems appear in the text, with concise explanations of the basic notions and theorems to be used in their solution. Many are followed by complete answers; solutions for the others appear at the end of the book. Topics include sequences, functions of a single variable, limit of a function, differential calculus for functions of a single variable, fundamental theorems and applications of dif
A comprehensive analytical solution of the nonlinear pendulum
Energy Technology Data Exchange (ETDEWEB)
Ochs, Karlheinz, E-mail: ochs@ieee.org [Chair of Communications, Department of Electrical Engineering and Information Technology, Ruhr-University Bochum (Germany)
2011-03-15
In this paper, an analytical solution for the differential equation of the simple but nonlinear pendulum is derived. This solution is valid for any time and is not limited to any special initial instance or initial values. Moreover, this solution holds if the pendulum swings over or not. The method of approach is based on Jacobi elliptic functions and starts with the solution of a pendulum that swings over. Due to a meticulous sign correction term, this solution is also valid if the pendulum does not swing over.
Phenomenology of polymer solution dynamics
National Research Council Canada - National Science Library
Phillies, George D. J
2011-01-01
... solutions, not dilute solutions or polymer melts. From centrifugation and solvent dynamics to viscosity and diffusion, experimental measurements and their quantitative representations are the core of the discussion...
Aliteracy : causes and solutions
Nielen, Thijs Martinus Johannes
2016-01-01
The reading motivation of the majority of students declines in the upper half of primary school, which implies a risk for aliteracy: Students can read but, due to lack of practice, their skills remain underdeveloped (Chapter 2). In this thesis we have explored causes and solutions for this important
School Solutions for Cyberbullying
Sutton, Susan
2009-01-01
This article offers solutions and steps to prevent cyberbullying. Schools can improve their ability to handle cyberbullying by educating staff members, students, and parents and by implementing rules and procedures for how to handle possible incidents. Among the steps is to include a section about cyberbullying and expectations in the student…
Antisocial Personalities, Antidemocractic Solutions.
Schneiderman, Howard G.
1996-01-01
Provides critical analysis of David T. Lykken's article "Psychopathy, Sociopathy, and Crime" (1996) and its correlation between unstable families and sociopathy and the use of parental licensing as a solution. Discusses reasons for the appeal of parental licensing as well as the issue of state control replacing social control. (GR)
Cells and Hypotonic Solutions.
Bery, Julia
1985-01-01
Describes a demonstration designed to help students better understand the response of plant and animal cells to hypotonic solutions. The demonstration uses a balloon inside a flexible, thin-walled cardboard box. Air going in corresponds to water entering by osmosis, and, like real cells, if stretched enough, the balloon will burst. (DH)
Glycosylation of solute carriers
DEFF Research Database (Denmark)
Pedersen, Nis Borbye; Carlsson, Michael C; Pedersen, Stine Helene Falsig
2016-01-01
Solute carriers (SLCs) are one of the largest groups of multi-spanning membrane proteins in mammals and include ubiquitously expressed proteins as well as proteins with highly restricted tissue expression. A vast number of studies have addressed the function and organization of SLCs as well...
Solution-focused premarital counseling: helping couples build a vision for their marriage.
Murray, Christine E; Murray, Thomas L
2004-07-01
This article outlines a solution-focused approach to premarital counseling. Solution-focused premarital counseling is a strength-based approach that focuses on a couple's resources to develop a shared vision for the marriage. Background information about premarital counseling and solution-focused therapy provide the framework for the development of intervention strategies that are grounded in the solution-focused approach. Solution-oriented interventions include solution-oriented questions, providing feedback, and the Couple's Resource Map, an original intervention that is described in this article.
INTERCULTURAL MISUNDERSTANDINGS: CAUSES AND SOLUTIONS
Directory of Open Access Journals (Sweden)
Майкл Б Хиннер
2017-12-01
Full Text Available Intercultural misunderstandings involve a number of complex causes which can easily escalate into conflicts. Since conflicts are also complex, it is not easy to find solutions because there is no one solution for all problems. Systems Theory, transdisciplinarity, and the social ecological model take a holistic approach in investigating complex phenomena. They permit the creation of a theoretical framework based on previous empirical research and theories across scientific disciplines to identify the relevant elements of complex phenomena and to understand the interrelationship of these elements. Intercultural misunderstandings and conflicts are very complex phenomena because they include culture, perception, identity, ethnocentrism, relationships, trust building and conflict management as well as intercultural commu-nication competence which entails cognition, metacognition, and social metacognition. Since most em-pirical studies focus on isolated, individual elements in specific contexts, this article describes the theoretical framework of how the various findings and theories developed in different scientific disciplines can be used to form a cohesive framework to help circumvent intercultural misunderstandings and conflicts. In so doing, it follows the general principles of Systems Theory, transdisciplinarity, and the social ecological model.
Tisdell, Christopher C.
2017-01-01
For over 50 years, the learning of teaching of "a priori" bounds on solutions to linear differential equations has involved a Euclidean approach to measuring the size of a solution. While the Euclidean approach to "a priori" bounds on solutions is somewhat manageable in the learning and teaching of the proofs involving…
Emotions in solution-focused therapy: a re-examination.
Miller, G; de Shazer, S
2000-01-01
This article re-examines whether and how emotions are an aspect of solution-focused therapy. A major theme in the article focuses on the usual ways that therapists define and discuss emotions in solution-focused and other therapies. We argue that these discussions are a source of much confusion about emotions and about solution-focused therapy, including the confusing idea that emotions are neglected in solution-focused therapy. The second major theme describes an alternative approach to these issues, one that we believe better fits with the assumptions and concerns of solution-focused therapy. The approach is based on Wittgenstein's writings about language games, private experience, and how emotions are rule-following activities. Viewed from this perspective, solution-focused therapists take account of their clients' emotions by helping clients to create new emotion rules to follow.
Teaching assistants' beliefs regarding example solutions in introductory physics
Lin, Shih-Yin; Mamudi, William; Singh, Chandralekha; Yerushalmi, Edit
2016-01-01
As part of a larger study to understand instructors' considerations regarding the learning and teaching of problem solving in an introductory physics course, we investigated beliefs of first-year graduate teaching assistants (TAs) regarding the use of example solutions in introductory physics. In particular, we examine how the goal of promoting expert-like problem solving is manifested in the considerations of graduate TAs choices of example solutions. Twenty-four first-year graduate TAs were asked to discuss their goals for presenting example solutions to students. They were also provided with different example solutions and asked to discuss their preferences for prominent solution features. TAs' awareness, preferences and actual practices related to solution features were examined in light of recommendations from the literature for the modeling of expert-like problem solving approaches. The study concludes that the goal of helping students develop an expert-like problem solving approach underlies many TAs' ...
Stiff fluid spike solutions from Bianchi type V seed solutions
Gregoris, D.; Lim, W. C.; Coley, A. A.
2017-12-01
In this paper we expand upon our previous work Coley et al (2016 Class. Quantum Grav. 33 215010) by using the entire family of Bianchi type V stiff fluid solutions as seed solutions of the Stephani transformation. Among the new exact solutions generated, we observe a number of important physical phenomena. The most interesting phenomenon is exact solutions with intersecting spikes. Other interesting phenomena are solutions with saddle states and a close-to-FL epoch.
Implementing SaaS Solution for CRM
Directory of Open Access Journals (Sweden)
Adriana LIMBASAN
2011-01-01
Full Text Available Greatest innovations in virtualization and distributed computing have accelerated interest in cloud computing (IaaS, PaaS, SaaS, aso. This paper presents the SaaS prototype for Customer Relationship Management of a real estate company. Starting from several approaches of e-marketing and SaaS features and architectures, we adopted a model for a CRM solution using SaaS Level 2 architecture and distributed database. Based on the system objective, functionality, we developed a modular solution for solve CRM and e-marketing targets in real estate companies.
On the solution topologies of polytropic winds
Bailyn, C.; Rosner, R.; Tsinganos, K.
1985-01-01
Steady polytropic wind flows are studied by examining their solution topologies. The problem of whether the degeneracy of the continuous and standing shocked solutions in the isothermal case persist in the more general case of a polytropic expanding atmosphere is addressed. The effects of departures from spherical symmetry and nonthermal momentum addition are considered within the context of the new class of magnetospheric models proposed by Low and Tsinganos (1985). The flow near the boundary of a polar coronal hole is considered for the specific case of a magnetosphere in which this boundary asymptotically approaches the equator at large heliocentric distances.
Accurate simulation of protein dynamics in solution
Energy Technology Data Exchange (ETDEWEB)
Levitt, M.; Sharon, R. (Weizmann Institute of Science, Rehovot (Israel))
1988-10-01
Simulation of the molecular dynamics of a small protein, bovine pancreatic trypsin inhibitor, was found to be more realistic when water molecules were included than when in vacuo: the time-averaged structure was much more like that observed in high-resolution x-ray studies, the amplitudes of atomic vibration in solution were smaller, and fewer incorrect hydrogen bonds were formed. The authors approach, which provides a sound basis for reliable simulation of diverse properties of biological macromolecules in solution, uses atom-centered forces and classical mechanics.
Varied reasoning schema in students' written solutions
Weliweriya, Nandana; Sayre, Eleanor C; Zollman, Dean
2016-01-01
The Mathematization project investigates students' use of mathematical tools across the undergraduate physics curriculum. As a part of this project, we look at intermediate mechanics students' written homework solutions to understand how they use those tools in approaching traditional mechanics problems. We use a modified version of the ACER framework to analyze students' solutions and to identify patterns of mathematical skills used on traditional problems. We apply techniques borrowed from network analysis and the Resources Framework to build a "fingerprint" of students' mathematical tool use. In this paper, we present preliminary findings on patterns that we identified in students' problem solving.
Applied Integer Programming Modeling and Solution
Chen, Der-San; Dang, Yu
2011-01-01
An accessible treatment of the modeling and solution of integer programming problems, featuring modern applications and software In order to fully comprehend the algorithms associated with integer programming, it is important to understand not only how algorithms work, but also why they work. Applied Integer Programming features a unique emphasis on this point, focusing on problem modeling and solution using commercial software. Taking an application-oriented approach, this book addresses the art and science of mathematical modeling related to the mixed integer programming (MIP) framework and
Iterative Solutions to the Inverse Geometric Problem for Manipulators with no Closed Form Solution
Directory of Open Access Journals (Sweden)
Pål Johan From
2008-07-01
Full Text Available A set of new iterative solutions to the inverse geometric problem is presented. The approach is general and does not depend on intersecting axes or calculation of the Jacobian. The solution can be applied to any manipulator and is well suited for manipulators for which convergence is poor for conventional Jacobian-based iterative algorithms. For kinematically redundant manipulators, weights can be applied to each joint to introduce stiffness and for collision avoidance. The algorithm uses the unit quaternion to represent the position of each joint and calculates analytically the optimal position of the joint when only the respective joint is considered. This sub-problem is computationally very efficient due to the analytical solution. Several algorithms based on the solution of this sub-problem are presented. For difficult problems, for which the initial condition is far from a solution or the geometry of the manipulator makes the solution hard to reach, it is shown that the algorithm finds a solution fairly close to the solution in only a few iterations.
Earnest Rutherford, the solution
2003-01-01
If you did not make it to the Science & Society talk by John Campbell last week and are still wondering about the spelling of "Earnest", here is the solution: Two months after the birth of his fourth child on 30 August 1871 in Spring Grove, New Zealand, James Rutherford registered his son, who was recorded as "Earnest" in the Birth Register. Presumably the Registrar wrote the name down as it sounded and the father failed to notice the mistake when signing the Register.
Solution Processing - Rodlike Polymers
1979-08-01
side it necessary and identify by block number) Para-ordered Polymers High Modulus Fibers and Films Polybenzobisoxazoles Polybenzobisthiazoles 20...considerations important in solution processing are considered, with special emphasis on the dry-jet wet spinning process used to form fibers . Pertinent...Company, Summit, N.J. iii TABLE OF CONTENTS 1. INTRODUCTION ................ .......................... .. 1 2. REMARKS ON DRY-JET WET SPUN FIBER
Optimization of process and solution parameters in electrospinning polyethylene oxide
CSIR Research Space (South Africa)
Jacobs, V
2011-11-01
Full Text Available This paper reports the optimization of electrospinning process and solution parameters using factorial design approach to obtain uniform polyethylene oxide (PEO) nanofibers. The parameters studied were distance between nozzle and collector screen...
Designing Integrated Product- Service System Solutions in Manufacturing Industries
DEFF Research Database (Denmark)
Costa, Nina; Patrício, Lia; Morelli, Nicola
2015-01-01
Manufacturing firms are increasingly evolving towards the design of integrated product-service solutions but servitization literature does not provide specific guidance on how to design these integrated solutions. Building upon ProductService System (PSS) and Service Design (SD) approaches...... how it brings new insights to manufacturing companies moving to a service, value cocreation perspective....
Intuitive Understanding of Solutions of Partially Differential Equations
Kobayashi, Y.
2008-01-01
This article uses diagrams that help the observer see how solutions of the wave equation and heat conduction equation are obtained. The analytical approach cannot necessarily show the mechanisms of the key to the solution without transforming the differential equation into a more convenient form by separation of variables. The visual clues based…
New exact solutions of the generalized Zakharov–Kuznetsov ...
Indian Academy of Sciences (India)
In this paper, new exact solutions, including soliton, rational and elliptic integral function solutions, for the generalized Zakharov–Kuznetsov modified equal-width equation are obtained using a new approach called the extended trial equation method. In this discussion, a new version of the trial equation method for the ...
Existence of Positive Solutions of Neutral Differential Equations
Directory of Open Access Journals (Sweden)
B. Dorociaková
2012-01-01
Full Text Available The paper contains some suffcient conditions for the existence of positive solutions which are bounded below and above by positive functions for the nonlinear neutral differential equations of higher order. These equations can also support the existence of positive solutions approaching zero at infinity.
Approximated solutions to Born-Infeld dynamics
Energy Technology Data Exchange (ETDEWEB)
Ferraro, Rafael [Instituto de Astronomía y Física del Espacio (IAFE, CONICET-UBA),Casilla de Correo 67, Sucursal 28, 1428 Buenos Aires (Argentina); Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires,Ciudad Universitaria, Pabellón I, 1428 Buenos Aires (Argentina); Nigro, Mauro [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires,Ciudad Universitaria, Pabellón I, 1428 Buenos Aires (Argentina)
2016-02-01
The Born-Infeld equation in the plane is usefully captured in complex language. The general exact solution can be written as a combination of holomorphic and anti-holomorphic functions. However, this solution only expresses the potential in an implicit way. We rework the formulation to obtain the complex potential in an explicit way, by means of a perturbative procedure. We take care of the secular behavior common to this kind of approach, by resorting to a symmetry the equation has at the considered order of approximation. We apply the method to build approximated solutions to Born-Infeld electrodynamics. We solve for BI electromagnetic waves traveling in opposite directions. We study the propagation at interfaces, with the aim of searching for effects susceptible to experimental detection. In particular, we show that a reflected wave is produced when a wave is incident on a semi-space containing a magnetostatic field.
Microscopic approach to polaritons
DEFF Research Database (Denmark)
Skettrup, Torben
1981-01-01
The interaction between excitons and light has been investigated in detail. The perturbational approach turns out to be invalid. However, an exact solution can be obtained directly from the Schrödinger equation for a fixed light field. This solution corresponds to a nonlinear optical response...... contrary to experimental experience. In order to remove this absurdity the semiclassical approach must be abandoned and the electromagnetic field quantized. A simple microscopic polariton model is then derived. From this the wave function for the interacting exciton-photon complex is obtained...... of light of the crystal. The introduction of damping smears out the excitonic spectra. The wave function of the polariton, however, turns out to be very independent of damping up to large damping values. Finally, this simplified microscopic polariton model is compared with the exact solutions obtained...
Shuttle Wastewater Solution Characterization
Adam, Niklas; Pham, Chau
2011-01-01
During the 31st shuttle mission to the International Space Station, STS-129, there was a clogging event in the shuttle wastewater tank. A routine wastewater dump was performed during the mission and before the dump was completed, degraded flow was observed. In order to complete the wastewater dump, flow had to be rerouted around the dump filter. As a result, a basic chemical and microbial investigation was performed to understand the shuttle wastewater system and perform mitigation tasks to prevent another blockage. Testing continued on the remaining shuttle flights wastewater and wastewater tank cleaning solutions. The results of the analyses and the effect of the mitigation steps are detailed in this paper.
Determination of the activity of a molecular solute in saturated solution
Energy Technology Data Exchange (ETDEWEB)
Nordstroem, Fredrik L. [Department of Chemical Engineering and Technology, Royal Institute of Technology, 100 44 Stockholm (Sweden); Rasmuson, Ake C. [Department of Chemical Engineering and Technology, Royal Institute of Technology, 100 44 Stockholm (Sweden)], E-mail: rasmuson@ket.kth.se
2008-12-15
Prediction of the solubility of a solid molecular compound in a solvent, as well as, estimation of the solution activity coefficient from experimental solubility data both require estimation of the activity of the solute in the saturated solution. The activity of the solute in the saturated solution is often defined using the pure melt at the same temperature as the thermodynamic reference. In chemical engineering literature also the activity of the solid is usually defined on the same reference state. However, far below the melting temperature, the properties of this reference state cannot be determined experimentally, and different simplifications and approximations are normally adopted. In the present work, a novel method is presented to determine the activity of the solute in the saturated solution (=ideal solubility) and the heat capacity difference between the pure supercooled melt and solid. The approach is based on rigorous thermodynamics, using standard experimental thermodynamic data at the melting temperature of the pure compound and solubility measurements in different solvents at various temperatures. The method is illustrated using data for ortho-, meta-, and para-hydroxybenzoic acid, salicylamide and paracetamol. The results show that complete neglect of the heat capacity terms may lead to estimations of the activity that are incorrect by a factor of 12. Other commonly used simplifications may lead to estimations that are only one-third of the correct value.
Theory and computer simulation of solute effects on the surface tension of liquids.
Chen, Feng; Smith, Paul E
2008-07-31
A complete description of the thermodynamics of planar mixed solute-solvent interfaces suitable for the analysis of computer simulation data is provided. The approach uses surface probability distributions to characterize the interface regions, coupled with radial distribution functions and the Kirkwood-Buff theory of solutions to characterize the bulk solution properties. The approach is then used to understand the relationship between changes in the surface tension, the degree of surface adsorption or depletion, and the bulk solution properties of two aqueous solute systems. The first, aqueous NaCl solutions, provides an example of a surface excluded solute. The second, aqueous methanol solutions, provides an example of a surface adsorbed solute. The numerical results support the theoretical relationships described here and provide a consistent picture of the thermodynamics of solution interfaces involving any number of components which can be applied to a wide variety of systems.
Asymptotic Methods for Solitary Solutions and Compactons
Directory of Open Access Journals (Sweden)
Ji-Huan He
2012-01-01
Full Text Available This paper is an elementary introduction to some new asymptotic methods for the search for the solitary solutions of nonlinear differential equations, nonlinear differential-difference equations, and nonlinear fractional differential equations. Particular attention is paid throughout the paper to giving an intuitive grasp for the variational approach, the Hamiltonian approach, the variational iteration method, the homotopy perturbation method, the parameter-expansion method, the Yang-Laplace transform, the Yang-Fourier transform, and ancient Chinese mathematics. Hamilton principle and variational principles are also emphasized. The reviewed asymptotic methods are easy to be followed for various applications. Some ideas on this paper are first appeared.
Theory of Polyelectrolyte Solutions
Barrat, Jean-Louis; Joanny, Jean-Francois
1996-01-01
1. Introduction 2. Charged chains at infinite dilution - asymptotic properties 2.1 Definition of the model and Flory-like calculation 2.2 Variational approaches 2.3 Renormalization group calculations 2.4 Screening of electrostatic interactions 2.5 Annealed and quenched polyelectrolytes 3. Local aspects of screening 3.1 Counterion condensation 3.2 Poisson Boltzmann approach 3.3 Attractive electrostatic interactions 4. Electrostatic rigidity 4.1 The Odijk-Skolnick-Fixman theory 4.2 Alternative ...
Denschlag, Robert; Lingenheil, Martin; Tavan, Paul; Mathias, Gerald
2009-10-13
For the enhanced conformational sampling in molecular dynamics (MD) simulations, we present "simulated solute tempering" (SST) which is an easy to implement variant of simulated tempering. SST extends conventional simulated tempering (CST) by key concepts of "replica exchange with solute tempering" (REST, Liu et al. Proc. Natl. Acad. Sci. U.S.A. 2005, 102, 13749). We have applied SST, CST, and REST to molecular dynamics (MD) simulations of an alanine octapeptide in explicit water. The weight parameters required for CST and SST are determined by two different formulas whose performance is compared. For SST only one of them yields a uniform sampling of the temperature space. Compared to CST and REST, SST provides the highest exchange probabilities between neighboring rungs in the temperature ladder. Concomitantly, SST leads to the fastest diffusion of the simulation system through the temperature space, in particular, if the "even-odd" exchange scheme is employed in SST. As a result, SST exhibits the highest sampling speed of the investigated tempering methods.
Rational homoclinic solution and rogue wave solution for the ...
Indian Academy of Sciences (India)
In this paper, a rational homoclinic solution is obtained via the classical homoclinicsolution for the coupled long-wave–short-wave system. Based on the structures of ratinal homoclinic solution, the characteristics of homoclinic solution are discussed which might provide us with useful information on the dynamics of the ...
Solution of IVP of Second Order ODE with Oscillatory Solutions ...
African Journals Online (AJOL)
A Numerical method for solution of IVP of second order with oscillatory solutions using VIM is developed. The method is applied to solve some initial value problems of second order ODE with oscillatory solutions. The results are compared with some existing methods and found to compete favourably with existing methods.
Solute-Filled Syringe For Formulating Intravenous Solution
Owens, Jim; Bindokas, AL; Dudar, Tom; Finley, Mike; Scharf, Mike
1993-01-01
Prefilled syringe contains premeasured amount of solute in powder or concentrate form used to deliver solute to sterile interior of large-volume parenteral (LVP) bag. Predetermined amount of sterile water also added to LVP bag through sterilizing filter, and mixed with contents of syringe, yielding sterile intravenous solution of specified concentration.
Oral Misoprostol Solution for Induction of Labour.
Deshmukh, Varsha L; Rajamanya, Apurva V; Yelikar, K A
2017-04-01
To determine the effects of oral misoprostol solution for induction of labour. This is a prospective observational study. This study was conducted in Government Medical College, Aurangabad. Patients undergoing induction of labour after 36 weeks of pregnancy were allocated by randomization to induction of labour with oral misoprostol solution administered 2 h apart. Delivery within 24 h after induction with oral misoprostol solution was the primary outcome on which the sample size was based. The data were analysed by Statistical Software for Social Sciences software. Two hundred patients were randomly selected for induction with oral misoprostol solution. There were no significant differences in substantive outcomes. Vaginal delivery within 24 h was achieved in 80.5 % of patients. The caesarean section rate was 19.5 %. Uterine hyperactivity occurred in 4 % of patients. The response to induction of labour in women with unfavourable cervices (modified Bishop's score induction to delivery interval was more, oxytocin requirement was more, and vaginal delivery rate was less. This new approach to oral misoprostol solution administration was successful in achieving vaginal delivery rate in 24 h in 80.5 % of patients; rate of LSCS was less 19.5 %.
Severe asthma: emergency care patient driven solutions.
Newell, Karen; Corrigan, Chris; Punshon, Geoffrey; Leary, Alison
2017-08-14
Purpose Patients with severe asthma were choosing not to use the emergency department (ED) in extremis and were self-medicating when experiencing severe asthma, putting their lives at risk. This local issue reflected a nationwide situation. The purpose of this paper is to better understand the reasons behind patients' reluctance to attend ED and to consider practical solutions in a structured way. Design/methodology/approach Systems thinking (soft systems methodology) was used to examine the issues resulting in this reluctance to attend the ED. Once this tame (well-defined) problem was revealed, a potential solution was developed in co-production with patients. Findings Patients feared attending the ED and felt vulnerable while in the ED for several reasons. This appeared to be a well-defined and solvable problem. The solution proposed was an asthma patient passport (APP), which increased patient's confidence in their ability to communicate their needs while in severe distress. The APP decreases (from 12 to 5 steps) the work patients had to do to achieve care. The APP project is currently being evaluated. Practical implications The APP should be offered to all people with severe asthma. Originality/value By revisiting systems thinking and identifying problems, a solution was identified. Although methods such as soft systems methodology have limitations when used in wicked (difficult or impossible to resolve) problems, such methods still have merit in tame problems and were applicable in this case to fully understand the issues, and to design practical solutions.
DEFF Research Database (Denmark)
Gupta, Ritu; Walia, Sunil; Hösel, Markus
2014-01-01
A simple method for producing patterned Ag electrodes on transparent and flexible substrates is reported. The process makes use of laser printed toner as a sacrificial template for an organic precursor, which upon thermolysis and toner lift off produced highly conducting Ag electrodes. Thus, the ...... solar cells have been demonstrated. The method is extendable to produce defect-free patterns over large areas as demonstrated by roll coating....
Radionuclide solubility control by solid solutions
Energy Technology Data Exchange (ETDEWEB)
Brandt, F.; Klinkenberg, M.; Rozov, K.; Bosbach, D. [Forschungszentrum Juelich GmbH (Germany). Inst. of Energy and Climate Research - Nuclear Waste Management and Reactor Safety (IEK-6); Vinograd, V. [Frankfurt Univ. (Germany). Inst. of Geosciences
2015-07-01
The migration of radionuclides in the geosphere is to a large extend controlled by sorption processes onto minerals and colloids. On a molecular level, sorption phenomena involve surface complexation, ion exchange as well as solid solution formation. The formation of solid solutions leads to the structural incorporation of radionuclides in a host structure. Such solid solutions are ubiquitous in natural systems - most minerals in nature are atomistic mixtures of elements rather than pure compounds because their formation leads to a thermodynamically more stable situation compared to the formation of pure compounds. However, due to a lack of reliable data for the expected scenario at close-to equilibrium conditions, solid solution systems have so far not been considered in long-term safety assessments for nuclear waste repositories. In recent years, various solid-solution aqueous solution systems have been studied. Here we present state-of-the art results regarding the formation of (Ra,Ba)SO{sub 4} solid solutions. In some scenarios describing a waste repository system for spent nuclear fuel in crystalline rocks {sup 226}Ra dominates the radiological impact to the environment associated with the potential release of radionuclides from the repository in the future. The solubility of Ra in equilibrium with (Ra,Ba)SO{sub 4} is much lower than the one calculated with RaSO{sub 4} as solubility limiting phase. Especially, the available literature data for the interaction parameter W{sub BaRa}, which describes the non-ideality of the solid solution, vary by about one order of magnitude (Zhu, 2004; Curti et al., 2010). The final {sup 226}Ra concentration in this system is extremely sensitive to the amount of barite, the difference in the solubility products of the end-member phases, and the degree of non-ideality of the solid solution phase. Here, we have enhanced the fundamental understanding regarding (1) the thermodynamics of (Ra,Ba)SO{sub 4} solid solutions and (2) the
Strong nonlinear oscillators analytical solutions
Cveticanin, Livija
2017-01-01
This book outlines an analytical solution procedure of the pure nonlinear oscillator system, offering a solution for free and forced vibrations of the one-degree-of-freedom strong nonlinear system with constant and time variable parameter. Includes exercises.
Persistent Self-Association of Solute Molecules in Solution.
Tang, Weiwei; Mo, Huaping; Zhang, Mingtao; Parkin, Sean; Gong, Junbo; Wang, Jingkang; Li, Tonglei
2017-11-02
The structural evolvement of a solute determines the crystallization outcome. The self-association mechanism leading to nucleation, however, remains poorly understood. Our current study explored the solution chemistry of a model compound, tolfenamic acid (TFA), in three different solvents mainly by solution NMR. It was found that hydrogen-bonded pairs of solute-solute or solute-solvent stack with each through forming a much weaker π-π interaction as the concentration increases. Depending on the solvent, configurations of the solution species may be retained in the resultant crystal structure or undergo rearrangement. Yet, the π-π stacking is always retained in the crystal regardless of the solvent used for the crystallization. The finding suggests that nucleation not only involves the primary intermolecular interaction (hydrogen bonding) but also engages the secondary forces in the self-assembly process.
Exact Solutions to Maccari's System
Pan, Jun-Ting; Gong, Lun-Xun
2007-07-01
Based on the generalized Riccati relation, an algebraic method to construct a series of exact solutions to nonlinear evolution equations is proposed. Being concise and straightforward, the method is applied to Maccari's system, and some exact solutions of the system are obtained. The method is of important significance in exploring exact solutions for other nonlinear evolution equations.
2010 Water & Aqueous Solutions
Energy Technology Data Exchange (ETDEWEB)
Dor Ben-Amotz
2010-08-13
Water covers more than two thirds of the surface of the Earth and about the same fraction of water forms the total mass of a human body. Since the early days of our civilization water has also been in the focus of technological developments, starting from converting it to wine to more modern achievements. The meeting will focus on recent advances in experimental, theoretical, and computational understanding of the behavior of the most important and fascinating liquid in a variety of situations and applications. The emphasis will be less on water properties per se than on water as a medium in which fundamental dynamic and reactive processes take place. In the following sessions, speakers will discuss the latest breakthroughs in unraveling these processes at the molecular level: Water in Solutions; Water in Motion I and II; Water in Biology I and II; Water in the Environment I and II; Water in Confined Geometries and Water in Discussion (keynote lecture and poster winners presentations).
Griscom, Bronson W.; Adams, Justin; Ellis, Peter W.; Houghton, Richard A.; Lomax, Guy; Miteva, Daniela A.; Schlesinger, William H.; Shoch, David; Siikamäki, Juha V.; Smith, Pete; Woodbury, Peter; Zganjar, Chris; Blackman, Allen; Campari, João; Conant, Richard T.; Delgado, Christopher; Elias, Patricia; Gopalakrishna, Trisha; Hamsik, Marisa R.; Herrero, Mario; Kiesecker, Joseph; Landis, Emily; Laestadius, Lars; Leavitt, Sara M.; Minnemeyer, Susan; Polasky, Stephen; Potapov, Peter; Putz, Francis E.; Sanderman, Jonathan; Silvius, Marcel; Wollenberg, Eva; Fargione, Joseph
2017-10-01
Better stewardship of land is needed to achieve the Paris Climate Agreement goal of holding warming to below 2 °C; however, confusion persists about the specific set of land stewardship options available and their mitigation potential. To address this, we identify and quantify “natural climate solutions” (NCS): 20 conservation, restoration, and improved land management actions that increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, and agricultural lands. We find that the maximum potential of NCS—when constrained by food security, fiber security, and biodiversity conservation—is 23.8 petagrams of CO2 equivalent (PgCO2e) y‑1 (95% CI 20.3–37.4). This is ≥30% higher than prior estimates, which did not include the full range of options and safeguards considered here. About half of this maximum (11.3 PgCO2e y‑1) represents cost-effective climate mitigation, assuming the social cost of CO2 pollution is ≥100 USD MgCO2e‑1 by 2030. Natural climate solutions can provide 37% of cost-effective CO2 mitigation needed through 2030 for a >66% chance of holding warming to below 2 °C. One-third of this cost-effective NCS mitigation can be delivered at or below 10 USD MgCO2‑1. Most NCS actions—if effectively implemented—also offer water filtration, flood buffering, soil health, biodiversity habitat, and enhanced climate resilience. Work remains to better constrain uncertainty of NCS mitigation estimates. Nevertheless, existing knowledge reported here provides a robust basis for immediate global action to improve ecosystem stewardship as a major solution to climate change.
National Research Council Canada - National Science Library
Salnikov, Oleg G; Kovtunov, Kirill V; Koptyug, Igor V
2015-01-01
An experimental approach for the production of catalyst-free hyperpolarised ethanol solution in water via heterogeneous hydrogenation of vinyl acetate with parahydrogen and the subsequent hydrolysis...
african solutions to africa's problems? african approaches to peace ...
African Journals Online (AJOL)
Ilse van der Walt
global powers. The African security environment today is a dynamic one, characterised by a volatile mix of conflict, instability and state weakness, and analysts have attempted to offer a ... only half of Africa's youth is economically active. ... lived on less than $1 a day and four out of ten Nigerians were unemployed.21 Under.
Kurtosis Approach to Solution of a Nonlinear ICA Problem
Duong, Vu; Stubberud, Allen
2009-01-01
An algorithm for solving a particular nonlinear independent-component-analysis (ICA) problem, that differs from prior algorithms for solving the same problem, has been devised. The problem in question of a type known in the art as a post nonlinear mixing problem is a useful approximation of the problem posed by the mixing and subsequent nonlinear distortion of sensory signals that occur in diverse scientific and engineering instrumentation systems.
Finite element approach to solution of multidimensional quasi ...
African Journals Online (AJOL)
The functional of a stress field function was established using mixed methods analogous to variational principle, minimum total potential principle and finite element method. The functional of function, Φ(x,y) was formed using Euler equivalent integral and finite element shape function for a function expressed in derivative ...
Current and New Approaches in GMO Detection: Challenges and Solutions
Directory of Open Access Journals (Sweden)
Marie-Alice Fraiture
2015-01-01
Full Text Available In many countries, genetically modified organisms (GMO legislations have been established in order to guarantee the traceability of food/feed products on the market and to protect the consumer freedom of choice. Therefore, several GMO detection strategies, mainly based on DNA, have been developed to implement these legislations. Due to its numerous advantages, the quantitative PCR (qPCR is the method of choice for the enforcement laboratories in GMO routine analysis. However, given the increasing number and diversity of GMO developed and put on the market around the world, some technical hurdles could be encountered with the qPCR technology, mainly owing to its inherent properties. To address these challenges, alternative GMO detection methods have been developed, allowing faster detections of single GM target (e.g., loop-mediated isothermal amplification, simultaneous detections of multiple GM targets (e.g., PCR capillary gel electrophoresis, microarray, and Luminex, more accurate quantification of GM targets (e.g., digital PCR, or characterization of partially known (e.g., DNA walking and Next Generation Sequencing (NGS or unknown (e.g., NGS GMO. The benefits and drawbacks of these methods are discussed in this review.
A stepwise planned approach to the solution of Hilbert's sixth ...
Indian Academy of Sciences (India)
Taking explicitly into consideration the fact that observations on the apparatus are made when it has 'settled down after the measurement interaction' and are restricted to macroscopically distinguishable pointer readings, the unwanted superpositions of (system + apparatus) states are shown to be suppressed; this provides ...
Current and new approaches in GMO detection: challenges and solutions.
Fraiture, Marie-Alice; Herman, Philippe; Taverniers, Isabel; De Loose, Marc; Deforce, Dieter; Roosens, Nancy H
2015-01-01
In many countries, genetically modified organisms (GMO) legislations have been established in order to guarantee the traceability of food/feed products on the market and to protect the consumer freedom of choice. Therefore, several GMO detection strategies, mainly based on DNA, have been developed to implement these legislations. Due to its numerous advantages, the quantitative PCR (qPCR) is the method of choice for the enforcement laboratories in GMO routine analysis. However, given the increasing number and diversity of GMO developed and put on the market around the world, some technical hurdles could be encountered with the qPCR technology, mainly owing to its inherent properties. To address these challenges, alternative GMO detection methods have been developed, allowing faster detections of single GM target (e.g., loop-mediated isothermal amplification), simultaneous detections of multiple GM targets (e.g., PCR capillary gel electrophoresis, microarray, and Luminex), more accurate quantification of GM targets (e.g., digital PCR), or characterization of partially known (e.g., DNA walking and Next Generation Sequencing (NGS)) or unknown (e.g., NGS) GMO. The benefits and drawbacks of these methods are discussed in this review.
ENTERPRISE MASHUPS: A NEW APPROACH FOR BUSINESS SOLUTIONS
Directory of Open Access Journals (Sweden)
MARIO PAREDES VALVERDE
2012-06-01
Full Text Available Un mashup es una aplicación web que integra el contenido desde diferentes proveedores con el fin de crear un nuevo servicio que no es ofrecido por el proveedor de contenido. El desarrollo de estas aplicaciones incluye actividades tales como el acceso a fuentes heterogéneas, combinación de datos procedentes de diversas fuentes y la creación de interfaces gráficas. Este factor limita a los usuarios no experimentados en el desarrollado de aplicaciones con en el uso de computadores. Sin embargo, hoy en día hay empresas orientadas a crear herramientasque permiten a los usuarios sin experiencia la creación de mashups para responder a las necesidades de negocio de una forma fácil y rápida. Debido a esto, el enfoque de mashup empresarial ha sido ampliamente adoptado por un gran número de empresas. Este artículo presenta una visión general del enfoque de mashup empresarial, así como una revisiónde cuatro empresas orientadas a la producción de herramientas que ofrecen un conjunto de características que permite a los usuarios sin experiencia el desarrollo de mashups en una empresa. Por último,se presentan los desafíos que han de tenerse en cuenta por las empresas orientadas a la creación de herramientas de mashup empresarial con el fin de proporcionar una manera más fácil y más rápida de desarrollo de mashups
James, Trevor
2012-01-01
This book takes a step-by-step approach to building a complete business website using Drupal and enhancing it to include modern technology used by cutting-edge companies. All instructions are written in such a way that they make sense to readers of any technical level. This book is for anyone who wants to learn how to set up a website quickly for their business using the super powerful Drupal open source content management software.
Enthalpy of solution of biuret in various aqueous electrolyte solutions and in an urea solution
Energy Technology Data Exchange (ETDEWEB)
Nishimura, Hisashi; Murakami, Sachio (Osaka City Univ. (Japan))
1989-06-30
Enthalpies of biuret which is simplest amido acid and does not have hydrophobic group, in various aqueous solutions and in urea solution were measured at 298.15K to clarify the influence of salt on polymer conformal changes of organism or structure and functions of membrane. The isoperibol calorimeter where the quartz thermometer was used as the thermal sensor, was used in the measurement. The performance of this calorimeter was tested by comparing measurements with values in references. From the analysis of enthalpies of biuret solutions, following results of solute-solute-solvent interactions could be obtained: the rate where biuret destroys water structure is smaller in salt solutions than in aqueous solutions and the tendency depends on the ion size; ion-water interaction weakens owing to the ion-biuret interaction in salt solution of biuret; and water molecules are made free. 25 refs., 4 figs., 5 tabs.
Construction of an exact solution of time-dependent Ginzburg ...
Indian Academy of Sciences (India)
A new approach is taken to calculate the speed of front propagation at which the interface moves from a superconducting to a normal region in a superconducting sample. Using time-dependent Ginzburg–Landau (TDGL) equations we have calculated the speed by constructing a new exact solution. This approach is based ...
Construction of an exact solution of time-dependent Ginzburg ...
Indian Academy of Sciences (India)
Abstract. A new approach is taken to calculate the speed of front propagation at which the interface moves from a superconducting to a normal region in a superconducting sample. Using time-dependent Ginzburg–Landau (TDGL) equations we have calculated the speed by constructing a new exact solution. This approach ...
Bringing nature-based solutions to scale
Jongman, Brenden; Lange, Glenn-Marie; Balog, Simone; van Wesenbeeck, Bregje
2017-04-01
Coastal communities in developing countries are highly exposed and vulnerable to coastal flood risk, and are likely to suffer from climate change induced changes in risk. Over the last decade, strong evidence has surfaced that nature-based solutions or ecosystem-based approaches are efficient and effective alternatives for flood risk reduction and climate change adaptation. In developing countries, numerous projects have therefore been implemented, often driven by international donors and NGOs. Some of these projects have been successful in reducing risk while improving environmental and socioeconomic conditions. However, the feasibility assessment, design and implementation of nature-based solutions is a multifaceted process, which needs to be well-understood before such solutions can be effectively implemented as an addition or alternative to grey infrastructure. This process has not always been followed. As a result, many projects have failed to deliver positive outcomes. The international community therefore has a challenge in bringing nature-based solutions to scale in an effective way. In this presentation, we will present best practice guidelines on nature-based solution implementation that are currently being discussed by the international community. Furthermore, we will present the alpha version of a new web platform being developed by the World Bank that will serve as a much-needed central repository for project information on nature-based solutions, and that will host actionable implementation guidelines. The presentation will also serve as an invitation to the scientific community to share their experience and lessons learned, and contribute to the outlining of best practice guidance.
Energy Technology Data Exchange (ETDEWEB)
Cowley, David E.; Berman, Marc J.; Breinlinger, Helmut; Gilly, Ladina; Graves, Sam; Kovatch, Patricia; Kulesza, Pete; Martinez, Dave; Minyard, Tommy; Prucnal, Dave; Seager, Mark; Vadgama, Ash
2011-03-19
How can HPC centers reduce cost and environmental impact by making creative use of local natural resources? Energy efficiency inside the data center is only part of the story. In keeping with the principle of reduce, reuse, recycle, we should be able to take advantage of local resources to increase efficiency either at new or existing locations. Are there creative ways to reduce PUE below 1? Is a more meaningful way needed to express and measure the environmental effects of operating HPC centers? We will explore approaches such as sustainable energy sources, use of ambient external air or water temperatures, and reuse of "waste" heat.
Implementing Cisco UCS solutions
Ahmed, Farhan
2013-01-01
A tutorial-based approach which will help you understand the practical methodologies and deploying of Cisco UCS components.If you are a professional such as a system, network, or storage administrator who is responsible for Cisco UCS deployments, this is the perfect book for you. You should have some basic knowledge of the server's architecture, network, and storage technologies. Familiarity with virtualization technologies is also recommended (though not necessary) as the majority of real-world UCS deployments run virtualized loads. Knowledge of Nexus OS is not necessary as the majority of th
Future climate. Engineering solutions
Energy Technology Data Exchange (ETDEWEB)
Ferdinand, J.F.; Hagedorn-Rasmussen, P.; Fonnesbech, B.
2009-09-15
Future Climate Engineering Solutions - Joint Report is the common output and a documentation of more than 1 year's effort by 13 engineering associations - in 12 countries - to demonstrate how technologies can combat climate change. The report consists of three parts: Summaries of 10 national climate plans and technology prospects, 5 Key Common Findings, and a Climate Call from Engineers to create a new global climate treaty. The basic assumption of the project is recognition that GHG emissions, and their concentration in the atmosphere, must be reduced to a sustainable level. The project definition of a sustainable level is equivalent to the best-case stabilisation scenario which was presented in the 4th Assessment Report (AR4) by the UN Intergovernmental Panel on Climate Change (IPCC), whereby the global mean temperature is most likely to stabilise at 2.0-2.4 deg. C. The Future Climate website www.futureclimate.info holds more information about the project, including possibility to download project material, including the full national climate plans.
Directory of Open Access Journals (Sweden)
Brahim DENNAI
2011-08-01
Full Text Available Mixing rate is characterized by the diffusion flux given by the Fick’s law. A passive mixing strategy is proposed to enhance mixing of two fluids through perturbed jet flow. A numerical study of passive mixers has been presented. This paper is focused on the modeling of a micro-injection systems composed of passive amplifier without mechanical part. The micro-system modeling is based on geometrical oscillators form. An asymmetric micro-oscillator design based on a monostable fluidic amplifier is proposed. The characteristic size of the channels is generally about a few hundred of microns. The numerical results indicate that the mixing performance can be as high as 92 % within a typical mixing chamber of 2.25 mm diameter and 0.20 mm length when the Reynolds number is Re = 490. In addition, the results confirm that self-rotation in the circular mixer significantly enhances the mixing performance. The novel micro mixing method presented in this study provides a simple solution to mixing problems in micro system.
2003-01-01
From the company that brought the world an integral heating and cooling food service system after originally developing it for NASA's Apollo Program, comes yet another orbital offshoot: a product that can be as thin as paper and as strong as steel. Nextel Ceramic Textiles and Composites from 3M Company offer space-age protection and innovative solutions for hot situations, ranging from NASA to NASCAR. With superior thermal protection, Nextel fabrics, tape, and sleevings outperform other high temperature textiles such as aramids, carbon, glass, and quartz, permitting engineers and manufacturers to handle applications up to 2,500 F (1,371 C). The stiffness and strength of Nextel Continuous Ceramic Fibers make them a great match for improving the rigidity of aluminum in metal matrix composites. Moreover, the fibers demonstrate low shrinkage at operating temperatures, which allow for the manufacturing of a dimensionally stable product. These novel fibers also offer excellent chemical resistance, low thermal conductivity, thermal shock resistance, low porosity, and unique electrical properties.
Probabilistic approach to pattern selection
Yukalov, V. I.
2001-03-01
The problem of pattern selection arises when the evolution equations have many solutions, whereas observed patterns constitute a much more restricted set. An approach is advanced for treating the problem of pattern selection by defining the probability distribution of patterns. Then the most probable pattern naturally corresponds to the largest probability weight. This approach provides the ordering principle for the multiplicity of solutions explaining why some of them are more preferable than others. The approach is applied to solving the problem of turbulent photon filamentation in resonant media.
SU-F-R-10: Selecting the Optimal Solution for Multi-Objective Radiomics Model
Energy Technology Data Exchange (ETDEWEB)
Zhou, Z; Folkert, M; Wang, J [UT Southwestern Medical Center, Dallas, TX (United States)
2016-06-15
Purpose: To develop an evidential reasoning approach for selecting the optimal solution from a Pareto solution set obtained by a multi-objective radiomics model for predicting distant failure in lung SBRT. Methods: In the multi-objective radiomics model, both sensitivity and specificity are considered as the objective functions simultaneously. A Pareto solution set with many feasible solutions will be resulted from the multi-objective optimization. In this work, an optimal solution Selection methodology for Multi-Objective radiomics Learning model using the Evidential Reasoning approach (SMOLER) was proposed to select the optimal solution from the Pareto solution set. The proposed SMOLER method used the evidential reasoning approach to calculate the utility of each solution based on pre-set optimal solution selection rules. The solution with the highest utility was chosen as the optimal solution. In SMOLER, an optimal learning model coupled with clonal selection algorithm was used to optimize model parameters. In this study, PET, CT image features and clinical parameters were utilized for predicting distant failure in lung SBRT. Results: Total 126 solution sets were generated by adjusting predictive model parameters. Each Pareto set contains 100 feasible solutions. The solution selected by SMOLER within each Pareto set was compared to the manually selected optimal solution. Five-cross-validation was used to evaluate the optimal solution selection accuracy of SMOLER. The selection accuracies for five folds were 80.00%, 69.23%, 84.00%, 84.00%, 80.00%, respectively. Conclusion: An optimal solution selection methodology for multi-objective radiomics learning model using the evidential reasoning approach (SMOLER) was proposed. Experimental results show that the optimal solution can be found in approximately 80% cases.
Management Education Abroad: Adaptation versus a Cookie-Cutter Approach.
Mathews, Vinitia E.; Rivera, Joan B.; Pineda, Rodley C.
2001-01-01
Explores how educators might effectively deliver management education abroad. Presents cases for two different approaches, adapting to the local environment or using a cookie cutter approach, and discusses implementation issues of both approaches and possible solutions. (EV)
Optimal control solutions to sodic soil reclamation
Mau, Yair; Porporato, Amilcare
2016-05-01
We study the reclamation process of a sodic soil by irrigation with water amended with calcium cations. In order to explore the entire range of time-dependent strategies, this task is framed as an optimal control problem, where the amendment rate is the control and the total rehabilitation time is the quantity to be minimized. We use a minimalist model of vertically averaged soil salinity and sodicity, in which the main feedback controlling the dynamics is the nonlinear coupling of soil water and exchange complex, given by the Gapon equation. We show that the optimal solution is a bang-bang control strategy, where the amendment rate is discontinuously switched along the process from a maximum value to zero. The solution enables a reduction in remediation time of about 50%, compared with the continuous use of good-quality irrigation water. Because of its general structure, the bang-bang solution is also shown to work for the reclamation of other soil conditions, such as saline-sodic soils. The novelty in our modeling approach is the capability of searching the entire "strategy space" for optimal time-dependent protocols. The optimal solutions found for the minimalist model can be then fine-tuned by experiments and numerical simulations, applicable to realistic conditions that include spatial variability and heterogeneities.
Properties of scintillator solutes
Energy Technology Data Exchange (ETDEWEB)
Fluornoy, J.M.
1998-06-01
This special report summarizes measurements of the spectroscopic and other properties of the solutes that were used in the preparation of several new liquid scintillators developed at EG and G/Energy Measurements/Santa Barbara Operations (the precursor to Bechtel Nevada/Special Technologies Laboratory) on the radiation-to-light converter program. The data on the individual compounds are presented in a form similar to that used by Prof. Isadore Berlman in his classic handbook of fluorescence spectra. The temporal properties and relative efficiencies of the new scintillators are presented in Table 1, and the efficiencies as a function of wavelength are presented graphically in Figure 1. In addition, there is a descriptive glossary of the abbreviations used herein. Figure 2 illustrates the basic structures of some of the compounds and of the four solvents reported in this summary. The emission spectra generally exhibit more structure than the absorption spectra, with the result that the peak emission wavelength for a given compound may lie several nm away from the wavelength, {lambda}{sub avg}, at the geometric center of the emission spectrum. Therefore, the author has chosen to list absorption peaks, {lambda}{sub max}, and emission {lambda}{sub avg} values in Figures 3--30, as being most illustrative of the differences between the compounds. The compounds, BHTP, BTPB, ADBT, and DPTPB were all developed on this program. P-terphenyl, PBD, and TPB are commercially available blue emitters. C-480 and the other longer-wavelength emitters are laser dyes available commercially from Exciton Corporation. 1 ref., 30 figs.
Iodine addition using triiodide solutions
Rutz, Jeffrey A.; Muckle, Susan V.; Sauer, Richard L.
1992-01-01
The study develops: a triiodide solution for use in preparing ground service equipment (GSE) water for Shuttle support, an iodine dissolution method that is reliable and requires minimal time and effort to prepare, and an iodine dissolution agent with a minimal concentration of sodium salt. Sodium iodide and hydriodic acid were both found to dissolve iodine to attain the desired GSE iodine concentrations of 7.5 +/- 2.5 mg/L and 25 +/- 5 mg/L. The 1.75:1 and 2:1 sodium iodide solutions produced higher iodine recoveries than the 1.2:1 hydriodic acid solution. A two-hour preparation time is required for the three sodium iodide solutions. The 1.2:1 hydriodic acid solution can be prepared in less than 5 min. Two sodium iodide stock solutions (2.5:1 and 2:1) were found to dissolve iodine without undergoing precipitation.
Solute diffusion in liquid metals
Bhat, B. N.
1973-01-01
A gas model of diffusion in liquid metals is presented. In this model, ions of liquid metals are assumed to behave like the molecules in a dense gas. Diffusion coefficient of solute is discussed with reference to its mass, ionic size, and pair potential. The model is applied to the case of solute diffusion in liquid silver. An attempt was made to predict diffusion coefficients of solutes with reasonable accuracy.
Colligative properties of simple solutions.
Andrews, F C
1976-11-05
Vapor pressure lowering, osmotic pressure, boiling point elevation, and freezing point depression are all related quantitatively to the decrease in micro(1)(soln) upon the addition of solute in forming a solution. In any equilibrium system, regardless of whether it is in a gravitational field or whether it contains walls, semipermeable membranes, phase transitions, or solutes, all equilibria are maintained locally, in the small region of the equilibrium, by the equality of micro(1)(soln). If there are several subsystems in a gravitational field, at any fixed height, microi will have the same value in each subsystem into which substance i can get, and microi + M(i)gh is constant throughout the entire system. In a solution, there is no mechanism by which solvent and solute molecules could sustain different pressures. Both the solvent and solute are always under identical pressures in a region of solution, namely, the pressure of the solution in that region. Since nature does not know which component we call the solvent and which the solute, equations should be symmetric in the two (acknowledging that the nonvolatile component, if any, is commonly chosen to be solute). Simple molecular pictures illustrate what is happening to cause pressure (positive or negative) in liquids, vapor pressure of liquids, and the various colligative properties of solutions. The only effect of solute involved in these properties is that it dilutes the solvent, with the resulting increase in S and decrease in micro(1)(soln). Water can be driven passively up a tree to enormous heights by the difference between its chemical potential in the roots and the ambient air. There is nothing mysterious about the molecular bases for any of these phenomena. Biologists can use the well-understood pictures of these phenomena with confidence to study what is happening in the complicated living systems they consider.
Energy Technology Data Exchange (ETDEWEB)
Terasaki, K.; Oneda, S.
1988-07-01
A nonperturbative algebraic approach, which deals with long-distance physics in earnest but also maintains a close contact with quark-line diagrams, has previously been applied to the derivation of the chemically bond..delta..Ichemically bond = (1/2 rule in the K..-->..2..pi.. decays. Reasonable estimates of the rates of D/sup 0/..--> pi..K-bar and phiK-bar/sup 0/ decays in terms of the rate of K/sub S//sup 0/..--> pi pi.. decay have also been obtained, to the approximation in which excited state contributions to the on-mass-shell intermediate states are being neglected for the moment. In this paper, we examine our unified approach to the D..--> pi..K-bar, KK-bar, and ..pi pi.. and K..--> pi pi.. decays further, now including the four-quark (QQ)(Q-barQ-bar) meson contribution to the on-mass-shell intermediate states. We find that the result provides us with a solution to the well-known puzzle in the observed rates of various Cabibbo-suppressed decays of the D/sup 0/ meson, particularly GAMMA(D/sup 0/..-->..K/sup +/K/sup -/)/GAMMA(D/sup 0/..--> pi../sup +/..pi../sup -/)approx. =3.6, which has never been solved in a systematic manner. In addition, it gives us a significantly improved prediction on GAMMA(D/sup 0/..--> pi..K-bar) in comparison with GAMMA(K/sub S//sup 0/..--> pi pi..).
Abdelmoaty, Yomna H; Tessema, Tsemre-Dingel; Norouzi, Nazgol; El-Kadri, Oussama M; Turner, Joseph B McGee; El-Kaderi, Hani M
2017-10-18
Development of efficient sorbents for carbon dioxide (CO2) capture from flue gas or its removal from natural gas and landfill gas is very important for environmental protection. A new series of heteroatom-doped porous carbon was synthesized directly from pyrazole/KOH by thermolysis. The resulting pyrazole-derived carbons (PYDCs) are highly doped with nitrogen (14.9-15.5 wt %) as a result of the high nitrogen-to-carbon ratio in pyrazole (43 wt %) and also have a high oxygen content (16.4-18.4 wt %). PYDCs have a high surface area (SABET = 1266-2013 m(2) g(-1)), high CO2 Qst (33.2-37.1 kJ mol(-1)), and a combination of mesoporous and microporous pores. PYDCs exhibit significantly high CO2 uptakes that reach 2.15 and 6.06 mmol g(-1) at 0.15 and 1 bar, respectively, at 298 K. At 273 K, the CO2 uptake improves to 3.7 and 8.59 mmol g(-1) at 0.15 and 1 bar, respectively. The reported porous carbons also show significantly high adsorption selectivity for CO2/N2 (128) and CO2/CH4 (13.4) according to ideal adsorbed solution theory calculations at 298 K. Gas breakthrough studies of CO2/N2 (10:90) at 298 K showed that PYDCs display excellent separation properties. The ability to tailor the physical properties of PYDCs as well as their chemical composition provides an effective strategy for designing efficient CO2 sorbents.
Optimization of the annual construction program solutions
Directory of Open Access Journals (Sweden)
Oleinik Pavel
2017-01-01
Full Text Available The article considers potentially possible optimization solutions in scheduling while forming the annual production programs of the construction complex organizations. The optimization instrument is represented as a two-component system. As a fundamentally new approach in the first block of the annual program solutions, the authors propose to use a scientifically grounded methodology for determining the scope of work permissible for the transfer to a subcontractor without risk of General Contractor’s management control losing over the construction site. For this purpose, a special indicator is introduced that characterizes the activity of the general construction organization - the coefficient of construction production management. In the second block, the principal methods for the formation of calendar plans for the fulfillment of the critical work effort by the leading stream are proposed, depending on the intensity characteristic.
Structure and dynamics of solutions
Ohtaki, H
2013-01-01
Recent advances in the study of structural and dynamic properties of solutions have provided a molecular picture of solute-solvent interactions. Although the study of thermodynamic as well as electronic properties of solutions have played a role in the development of research on the rate and mechanism of chemical reactions, such macroscopic and microscopic properties are insufficient for a deeper understanding of fast chemical and biological reactions. In order to fill the gap between the two extremes, it is necessary to know how molecules are arranged in solution and how they change their pos
High conductivity electrolyte solutions and rechargeable cells incorporating such solutions
Angell, Charles Austen; Zhang, Sheng-Shui; Xu, Kang
1998-01-01
This invention relates generally to electrolyte solvents for use in liquid or rubbery polymer electrolyte solutions as are used, for example, in electrochemical devices. More specifically, this invention relates to sulfonyl/phospho-compound electrolyte solvents and sulfonyl/phospho-compound electrolyte solutions incorporating such solvents.
The Role of Green Infrastructure Solutions in Urban Flood Risk Management
Stanton-Geddes, Zuzana; Soz, Salman Anees; Kryspin-Watson, Jolanta
2016-01-01
This Knowledge Note explores the role of green infrastructure solutions in urban flood risk management. Green infrastructure solutions represent an approach that focuses on using natural processes for managing wet weather impacts while delivering environmental, social, and economic benefits. Green infrastructure solutions, such as wetlands, bioshields, buffer zones, green roofing, street s...
Viscosity Control of Protein Solution by Small Solutes: A Review.
Hong, Taehun; Iwashita, Kazuki; Shiraki, Kentaro
2017-12-12
Viscosity of protein solution is one of the most troublesome issues for the high-concentration formulation of protein drugs. In this review, we summarize the practical methods that suppress the viscosity of protein solution using small molecular additives. The small amount of salts decreases the viscosity that results from electrostatic repulsion and attraction. The chaotrope suppresses the hydrophobic attraction and cluster formation, which can lower the solution viscosity. Arginine hydrochloride (ArgHCl) also suppresses the solution viscosity due to the hydrophobic and aromatic interactions between protein molecules. The small molecular additives are the simplest resolution of the high viscosity of protein solution as well as understanding of the primary cause in complex phenomena of protein interactions. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Acquisition and Analysis of Data from High Concentration Solutions
Besong, Tabot M.D.
2016-05-13
The problems associated with ultracentrifugal analysis of macromolecular solutions at high (>10 mg/ml) are reviewed. Especially for the case of solutes which are non-monodisperse, meaningful results are not readily achievable using sedimentation velocity approaches. It is shown however by both simulation and analysis of practical data that using a modified form of an algorithm (INVEQ) published in other contexts, sedimentation equilibrium (SE) profiles can be analysed successfully, enabling topics such as oligomer presence or formation to be defined.To achieve this, it is necessary to employ an approach in which the solution density, which in an SE profile is radius-dependent, is taken into consideration. Simulation suggests that any reasonable level of solute concentration can be analysed.
Design principles for radiation-resistant solid solutions
Schuler, Thomas; Trinkle, Dallas R.; Bellon, Pascal; Averback, Robert
2017-05-01
We develop a multiscale approach to quantify the increase in the recombined fraction of point defects under irradiation resulting from dilute solute additions to a solid solution. This methodology provides design principles for radiation-resistant materials. Using an existing database of solute diffusivities, we identify Sb as one of the most efficient solutes for this purpose in a Cu matrix. We perform density-functional-theory calculations to obtain binding and migration energies of Sb atoms, vacancies, and self-interstitial atoms in various configurations. The computed data informs the self-consistent mean-field formalism to calculate transport coefficients, allowing us to make quantitative predictions of the recombined fraction of point defects as a function of temperature and irradiation rate using homogeneous rate equations. We identify two different mechanisms according to which solutes lead to an increase in the recombined fraction of point defects; at low temperature, solutes slow down vacancies (kinetic effect), while at high temperature, solutes stabilize vacancies in the solid solution (thermodynamic effect). Extension to other metallic matrices and solutes are discussed.
Inverse Kinematics With Closed Form Solution For Denso Robot Manipulator
Ikhsan Eka Prasetia; Trihastuti Agustinah
2015-01-01
In this paper, the forward kinematics and inverse kinematics used on the Denso robot manipulator which has a 6-DOF. The forward kinematics will result in the desired position by end-effector, while inverse kinematics produce angel on each joint. Inverse kinematics problem are very difficult, therefor to obtain the solution of inverse kinematics using closed form solution with geometry approach. The simulation result obtained from forward kinematics and inverse kinematics is determining desire...
Inverse Kinematics with Closed Form Solution for Denso Robot Manipulator
Prasetia, Ikhsan Eka; Agustinah, Trihastuti
2015-01-01
In this paper, the forward kinematics and inverse kinematics used on the Denso robot manipulator which has a 6-DOF. The forward kinematics will result in the desired position by end-effector, while inverse kinematics produce angel on each joint. Inverse kinematics problem are very difficult, therefor to obtain the solution of inverse kinematics using closed form solution with geometry approach. The simulation result obtained from forward kinematics and inverse kinematics is determining desire...
Solid Phase versus Solution Phase Synthesis of Heterocyclic Macrocycles
McAlpine, Shelli R.; Seong Jong Kim
2013-01-01
Comparing a solution phase route to a solid phase route in the synthesis of the cytotoxic natural product urukthapelstatin A (Ustat A) confirmed that a solid phase method is superior. The solution phase approach was tedious and involved cyclization of a ridged heterocyclic precursor, while solid phase allowed the rapid generation of a flexible linear peptide. Cyclization of the linear peptide was facile and subsequent generation of three oxazoles located within the structure of Ustat A proved...
Multiple Solutions for a Class of Fractional Boundary Value Problems
Directory of Open Access Journals (Sweden)
Ge Bin
2012-01-01
Full Text Available We study the multiplicity of solutions for the following fractional boundary value problem: where and are the left and right Riemann-Liouville fractional integrals of order , respectively, is a real number, is a given function, and is the gradient of at . The approach used in this paper is the variational method. More precisely, the Weierstrass theorem and mountain pass theorem are used to prove the existence of at least two nontrivial solutions.
Numerical solutions of the complete Navier-Stokes equations
Hassan, H. A.
1993-01-01
The objective of this study is to compare the use of assumed pdf (probability density function) approaches for modeling supersonic turbulent reacting flowfields with the more elaborate approach where the pdf evolution equation is solved. Assumed pdf approaches for averaging the chemical source terms require modest increases in CPU time typically of the order of 20 percent above treating the source terms as 'laminar.' However, it is difficult to assume a form for these pdf's a priori that correctly mimics the behavior of the actual pdf governing the flow. Solving the evolution equation for the pdf is a theoretically sound approach, but because of the large dimensionality of this function, its solution requires a Monte Carlo method which is computationally expensive and slow to coverage. Preliminary results show both pdf approaches to yield similar solutions for the mean flow variables.
Solution of the Classical Stefan Problem: Neumann Condition
Kot, V. A.
2017-07-01
A polynomial solution of the classical one-phase Stefan problem with a Neumann boundary condition is presented. As a result of the multiple integration of the heat-conduction equation, a sequence of identical equalities has been obtained. On the basis of these equalities, solutions were constructed in the form of the second-, third-, fourth-, and fifth-degree polynomials. It is shown by test examples that the approach proposed is highly efficient and that the approximation errors of the solutions in the form of the fourth- and fifth-degree polynomials are negligible small, which allows them to be considered in fact as exact. The polynomial solutions obtained substantially surpass the analogous numerical solutions in the accuracy of determining the position of the moving interphase boundary in a body and are in approximate parity with them in the accuracy of determining the temperature profile in it.
Nutrient solutions for soilless cultures
Sonneveld, C.; Voogt, W.
2009-01-01
Nutrient solutions intended for plant growth are already used from the middle of the 19th century, when the importance of mineral elements for plant growth was made clear by Justus von Liebig. In advance, the nutrient solutions used to grow plants in so called “water cultures” had a simple
Evaluation of ITRF2014 Solutions
Dach, Rolf; Grahsl, Andrea; Susnik, Andreja; Villiger, Arturo; Arnold, Daniel; Jäggi, Adrian
2017-04-01
For the most recent International Terrestrial Reference Frame (ITRF) realization three candidates have been provided, namely an ITRF2014 solution by IGN, DTRF2014 by DGFI-TUM, and JTRF2014 by JPL. There are significant differences in the way how these solutions have been generated, which parametrization has been applied, and how the solutions from the different space-geodetic techniques are combined. The most recent GNSS reprocessing solution generated in the frame of the EGSIEM project (European Gravity Service for Improved Emergency Management; funded by EC in the frame of Horizon 2020) was used to generate time series of GNSS-based solutions from 2000 to the end of 2014 using these reference frame realizations. The solution contains station coordinates, GNSS satellite orbits, Earth rotation parameters, and troposphere parameters. In order to evaluate the consistency of the contributions from the IGS (GNSS) and ILRS (SLR) in the reference frame solutions, the SLR measurements to the GNSS satellites can be used. Since the microwave-based GNSS satellite orbits obtained in the different reference frames are consistent regarding the orbit modeling differences in the SLR residuals may be interpreted to assess the consistency of the station coordinates between the SLR and GNSS sites in the reference frame solutions. With this contribution we hope to provide an independent contribution to the discussion about the advantages and disadvantages of the different methods to generate the IERS-TRF.