bluuebunny/crossref_metadata_2025_split huggingface dataset:
IMaX: a polarimeter based on Liquid Crystal Variable Retarders for an aerospace mission
Authors: Uribe‐Patarroyo N. , Alvarez‐Herrero A. , Heredero R. L. , del Toro Iniesta J. C. , López Jiménez A. C. , Domingo V. , Gasent J. L. , Jochum L. , Martínez Pillet V. , The IMaX Team  
Published: February 2008

AbstractIMaX is the Imaging Magnetograph eXperiment, an instrument part of the payload of SUNRISE, a stratospheric balloon mission in Antarctica. It is also the precursor of the Visible Imaging Magnetograph of the future ESA Solar Orbiter mission. It is essentially a diffraction‐limited imager that carries out spectropolarimetric measurements of high resolution (bandwidth of < 100 mÅ at 525.02 nm), and relates the polarimetric properties of the incoming light through a telescope with magnetic fields in the Sun, via the Zeeman effect. At the core of the instrument there are the polarization modulation components, two Liquid Crystal Variable Retarders (LCVRs). A demodulation efficiency is defined and used as the figure of merit, and it serves to find the theoretical optimum states for the LCVRs as well as to judge the quality of the pre‐flight calibration of the system. This calibration and the method used to optimize the actual efficiency is explained. Also, the space qualification of the LCVRs is presented, where ellipsometry played a major role in studying the effects of radiation, vacuum and temperature in the operation of the LCVRs. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spectroscopic ellipsometry on photonic crystals made by self‐assembled dye‐doped P(S/HEMA) nanospheres
Authors: Schutzmann S. , Prosposito P. , Casalboni M. , Venditti I. , Russo M. V. 
Published: February 2008

AbstractIn the present work the use of Spectroscopic Ellipsometry (SE) for a direct and non‐destructive optical and structural characterization of opaline photonic crystals is demonstrated. The analysis is performed on self‐assembled dye‐doped polymer nanospheres deposited on glass substrates. We study two different polymers beads: PMMA (as well‐known reference material) and poly[styrene‐(co‐2‐hydroxyethyl metacrylate)] [P(S/HEMA)]. We show that SE allows to obtain information about all the most important optical and geometrical features of the photonic structure as the effective refractive index (neff), the refractive index modulation, the optical anisotropy, the air/sphere filling fraction, the layer distance and the size of nanospheres. Results are in very good agreement with those obtained by Scanning Electron Microscope (SEM) analysis and Bragg reflection spectroscopy. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An auto‐focusing method for imaging ellipsometry system
Authors: Meng Y. H. , Chen S. , Jin G. 
Published: February 2008

AbstractAn auto‐focusing method based on the image brightness gradient sharpness function is presented for imaging ellipsometry system, in which the image plane of the thin‐film specimen is not perpendicular to the optical axis. The clear image of a specimen with large area is obtained by moving the imaging sensor in optical axis direction and around its sensitive surface centre successively. The experimental results demonstrate its feasibility. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecular dynamics simulations and hyperspherical mode analysis of NO in Kr crystals with the use of ab initio potential energy surfaces for the Kr‐NO complex
Authors: Castro Palacio Juan Carlos , Rubayo‐Soneira Jesús , Lombardi Andrea , Aquilanti Vincenzo 
Published: February 2008

AbstractThe dynamics of structural relaxation of NO doped Kr solids on electronic excitation of the NO molecule has been characterized by molecular dynamics simulations and by normal and hyperspherical mode analysis, with special emphasis on the effects of the anisotropy of the Kr–NO interaction which has been modeled by ab initio potential energy surfaces (PESs). The time evolution of the cage radius and the radial distribution function for the ground and excited states have been calculated for various orientations of the molecular axis with respect the Kr atom matrix with the NO molecule treated as a rigid rotor. The ab initio PESs, considered in previous work, seem to be too repulsive when compared with potentials fitted to spectroscopic data, and this is more evident for the first Ryberg state than for the ground state, where effects of potential anisotropy are less important. The first shell response shows a relative increase, up to ∼10%, of the excited state equilibrium radius with respect to that of the ground state, while experiments indicate that such an increase should be less than 5%. The kinetic energy power spectrum method, presented in a previous work, has been applied to the total kinetic energy T(t) and to two characteristic quantities of the hyperspherical mode analysis, the hyperradial energy Tρ(t) and the grand angular energy TΛ(t) for NO molecular axis orientations of 67° and 90°, respectively, which represent the cases of the largest and smallest lattice distortions in the radial distribution function (RDF) of the atoms in the matrix for the excited state. The band structures of the calculated frequency spectra reveal a blue shift with respect to the case of the isotropic potentials used previously, and this is connected to the different lattice equilibrium structures for 67° and 90° directions. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Direct injection of whole blood for liquid chromatography/tandem mass spectrometry analysis to support single‐rodent pharmacokinetic studies
Authors: Ingelse Benno A. , Vogel Gerard , Botterblom Margriet , Nanninga Dennis , Ooms Bert 
Published: February 2008

AbstractMass spectrometric developments in the last decade enable (sub)nanomolar detection of drug compounds in biological matrices in a few microliters of blood. However, the sampling and especially the handling of these small blood volumes is not straightforward. We studied the feasibility of a recently developed ‘sorbent sampling technique’ to handle these small blood volumes and the application to support pharmacokinetic (PK) screening programs. This technique applies 5–10 µL of blood on a fibrous material packed into a cartridge. Blood samples absorbed on these cartridges are eluted directly, on‐line onto a solid‐phase extraction liquid chromatography/tandem mass spectrometry (SPE‐LC/MS/MS) system. It is shown that the sorbent sampling technique can be applied for a range of drug compounds. In spite of issues with recovery and sample clean‐up that need further improvement, the sorbent sampling technique provided similar data as compared to conventional analytics. The technique was successfully applied to derive kinetic data from individual mice, thereby decreasing the number of required mice for a PK study from 21 to 3. Copyright © 2008 John Wiley & Sons, Ltd.
Network‐based H∞ control for stochastic systems
Authors: Meng Xiangyu , Lam James , Gao Huijun 
Published: February 2008

AbstractThis paper investigates the problem of network‐based control for stochastic plants. A new model of stochastic time‐delay systems is presented where both network‐induced delays and packet dropouts are taken into consideration for a sampled‐data network‐based control system. This model consists of two successive delay components in the state, and we solve the network‐based H∞ control problem based on this model by a new stochastic delay system approach. The controller design for the sampled‐data systems is carried out in terms of linear matrix inequalities. Finally, we illustrate the methodology by applying these results to an air vehicle control problem. Copyright © 2008 John Wiley & Sons, Ltd.
Derivatization of amino groups by pentafluorobenzaldehyde (PFB) as observed by XPS and NEXAFS spectroscopy on spin coated 4,4′‐methylenebis(2,6‐diethylaniline) films
Authors: Yegen E. , Lippitz A. , Treu D. , Unger W. E. S. 
Published: February 2008

AbstractA toluene solution of 4,4′‐methylenebis(2,6‐diethylaniline) was spin coated on Si wafers. The samples were derivatized with pentafluorobenzaldehyde (PFB) in order to determine the primary amino groups on the surface. XPS C 1s and N 1s and C and N K‐edge NEXAFS of underivatized and derivatized films were carefully analyzed. The result was that after 10 min of exposure the gas–surface reaction was already completed. A reasonable derivatization reaction yield in the order of 90% is derived from the experiments. This number correlates well to a reaction yield obtained by a wet chemical approach. Copyright © 2008 John Wiley & Sons, Ltd.
An experimental study of the electronic structure of anodically grown films on an amorphous Ni78Si8B14 alloy
Authors: Diplas S. , Knutsen T. , Jørgensen S. , Gunnæs A. E. , Våland T. , Norby T. , Olsen A. , Taftø J. 
Published: February 2008

AbstractFilms of Ni(OH)2 and NiOOH grown on a rapidly solidified amorphous Ni78Si8B14 alloy by anodic polarisation were analysed with XPS and the results were compared with those of NiO and of films grown on polycrystalline Ni. SIMS performed on the polarised alloy showed enrichment of Ni at the outermost surface. Transmission electron microscopy (TEM) of cross‐sectional samples showed an absence of crystallinity. The Ni 2p shake up satellite and valence band spectra suggested that NiOOH is characterised by a more enhanced n‐type semi‐conducting behaviour compared to Ni(OH)2 in agreement with earlier tunnelling current density measurements performed with scanning tunnelling spectroscopy (STS). Copyright © 2008 John Wiley & Sons, Ltd.
Origin of the redox deactivation phenomena in modified alumina‐supported Ce/Pr mixed oxide
Authors: Aboussaid Karima , Bernal Serafín , Blanco Ginesa , Cifredo Gustavo Aurelio , Galtayries Anouk , Pintado José María , el Begrani Mohamed Soussi 
Published: February 2008

AbstractIn this study, we have investigated the redox deactivation of a Ce/Pr mixed oxide supported on modified alumina. Two samples have been prepared by using silica‐ or lanthana‐modified alumina as supports: 25% Ce0.8Pr0.2O2−x/Al2O3‐SiO2 and 25% Ce0.8Pr0.2O2−x/Al2O3‐La2O3. The redox behavior was studied by reduction of the samples at selected temperatures, from 200 to 900 °C. Oxygen Storage Capacity (OSC) of reduced samples was measured by their reoxidation at 200 °C. The reduction degree attained by the supported mixed oxide, after reduction at temperatures up to 800 °C, increases in parallel for both samples. However, at 900 °C, there is a decrease of OSC, which is moderate for silica‐modified sample, while for lanthana‐modified catalyst, the OSC is almost negligible. XPS analysis of the fresh samples shows that the redox state of cerium cations close to the surface is mainly + 4, while praseodymium appears always as Pr3+. Samples reduced at different temperatures were also investigated by XPS. In the case of silica‐modified alumina reduced at 900 °C, significant amounts of Ce4+ can still be detected, which is in good agreement with the OSC value observed at that temperature. However, lanthana‐modified sample reduced at 800 °C shows an important amount of Ce3+, being the only oxidation state observed for cerium after reduction at 900 °C. This is in good agreement with the strong drop in OSC observed for this latter sample, which can be thus attributable to the trapping of trivalent cations by the alumina, forming a stable perovskite‐like aluminate, LnAlO3, as confirmed by X‐Ray Diffraction (XRD). Copyright © 2008 John Wiley & Sons, Ltd.
Surface modification of polymeric thin films with vacuum ultraviolet light
Authors: Sarantopoulou E. , Kovač J. , Kollia Z. , Raptis I. , Kobe S. , Cefalas A. C. 
Published: February 2008

AbstractSpin‐coated poly(methyl methacrylate) (PMMA) thin films on SiO2 substrate were chemically modified with laser light at 157 nm in nitrogen. Film changes involve bond breaking of polymeric chains, etching, and surface morphological changes. The 157 nm photons mainly dissociate the CO, CO, and CH bonds, and catalyze the formation of new CN bonds. The surface roughness of the irradiated films was changed with the formation of elongated patterns. The film thickness during irradiation was reduced with the rate of 0.005 nm at 1 mJ/cm2. Furthermore, the PMMA film forms a thin interface layer with the SiO2 substrate. Its thickness was reduced following vacuum ultraviolet (VUV) irradiation due to photodissociation of molecules inside the interface layer. Copyright © 2008 John Wiley & Sons, Ltd.
Perspectives on dietary fat, cancer report
Authors: Reddy Bandaru S. , Heyden Siegfried , Carroll K. K. , Hill Michael 
Published: February 2008

ConclusionThe lowering of blood cholesterol levels through changes in the fat quality which has proven beneficial in the prevention of heart attacks has had no undesirable side effects. Even more important, the reports on the frequency of cancer in the international dietary studies, between 1970 and 1982, have demonstrated a slight (and insignificant) reduction in cancer deaths, an unexpected bonus for adherence to a diet with less animal fat and more vegetable fats and oils.
An improved model for industrial vegetable oil hydrogenation
Authors: Moharir A. S. , Bhatia S. , Saraf D. N. 
Published: February 2008

AbstractA simplified mathematical model has been used to describe industrial vegetable oil hydrogenation. The temperature dependence of the reaction rate constants is taken into account. Data collected from full‐scale hydrogenation units are used to evaluate the model param‐eters. A simple technique is suggested for parameter estimation.
Determination of ultratrace metals in hydrogenated vegetable oils and fats
Authors: Nash A. M. , Mounts T. L. , Kwolek W. F. 
Published: February 2008

AbstractUltratrace levels of nickel, chromium, copper and iron occurring in hydrogenated vegetable oil products were estimated by dispersion of the samples in 4 methyl‐2‐pentanone and atomic absorption analysis by the graphite furnace technique. The principal goals in establishing the analytical methods were improved sensitivity to metals at low levels and applicability to limited amounts of products. Using reproducibility and linearity of response as criteria, optimum oil concentration in solvent and instrument parameters were established. For a series of commercial products, the method of standard additions was adopted to correct for matrix differences between the products and salad oil‐based standards. The range for the metals was determined in five cooking oils: Ni, 29–207 ppb; Cr, 1–5 ppb; Cu, 13–37 ppb; and Fe, 138–301 ppb; in recovered oils from five margarines: Ni, 34–70 ppb; Cr, 2–12 ppb; Cu, 26–58 ppb; and Fe, 239–540 ppb; and in five solid shortenings: Ni, 592–2772 ppb; Cr, 8–35 ppb; Cu, 26–108 ppb.
Physical and chemical properties of randomly interesterified blends of soybean oil and tallow for use as margarine oils
Authors: Lo Y. C. , Handel A. P. 
Published: February 2008

AbstractRefined, unhydrogenated soybean oil and edible beef tallow were interesterified with sodium methoxide. This was done as an alternative to hydrogenation for the production of plastic fats for use as margarine oils. Using 0.5% sodium methoxide at 80 C, interesterifi‐cation was complete in 30 min as determined by lipase hydrolysis. A blend of 60% soybean oil and 40% edible beef tallow was found to have physical characteristics (melting point, solid fat index) similar to those of commercial tub margarine oils. The level of poly‐unsaturated fatty acids was slightly lower and the level of saturated fatty acids slightly higher than the commercial margarine oils. Iodine value andtrans fatty acid determinations indicated no dis‐cernible effect on the degree of unsaturation or the level of isomeric fatty acids by the interesterification process. The interesterified blend did contain 3.0%trans fatty acids which were originally present in the tallow. Oxidative stability of the interesterified oils was estimated by peroxide value determinations over several days on samples stored at 60 C. Experimental blends treated with 0.1% citric acid had poorer stability than the partially hydrogenated margarine oils; however, 0.01% BHA significantly delayed oxidation of the experimental samples.
A time normalization study of the separation of olive oil triglycerides
Authors: Pauls R. E. 
Published: February 2008

AbstractA brief study on the selection of the optimal mobile phase for the reversed‐phase liquid Chromatographic separation of olive oil trigly‐cerides was carried out using a time normalization approach. Two parameters, the solvents comprising the binary mobile phase and the proportion of strong solvent in the binary mixture, were simultane‐ously varied in order to maintain the retention time of the last com‐ponent of interest fixed. Seven binary mobile phases were examined in the study. Plots of log k′ against percent strong solvent were found to be linear for all seven solvent pairs. This allowed prediction of the solvent composition needed to produce a given k’. A mixture of di‐chloromethane/acetonitrile gave optimal resolution for the triglycer‐ides under study. This time normalization approach offers a simple method directly to study effects of the variation of experimental parameters upon resolution.
A rapid argentation tlc method for detection of reesterified oils in olive and olive‐residue oils
Authors: Gegiou D. , Georgouli M. 
Published: February 2008

AbstractA rapid, simple and reproducible argentation thin layer Chromatog‐raphic method for the detection of reesterified oils in olive and olive‐residue oil is described. The sensitivity of the method is com‐parable to the sensitivity to the IUPAC method 2,210 for the determination of fatty acids in the 2‐position in the triglycerides of oils and fats.
The antioxidant activity of amino acids in two vegetable oils
Authors: Ahmad M. M. , Al‐Hakim S. , Adel A. , Shehata Y. 
Published: February 2008

AbstractOf 27 amino acids studied, most had some antioxidant activity when added in aqueous solution to either safflower oil or a mixture of sunflower and cottonseed oil (active oxygen and storage methods). Cysteine‐HCl, glutamic acid‐HCl (in the mixture), and glutamic acid‐HCl (in safflower oil) behaved as prooxidants. When added as a solid, most amino acids were ineffective. The protection factors of these amino acids were less than 1.3 in safflower oil with methionine, proline, lysine and cysteine providing the highest activ‐ity. In the oil mixture (which had a higher metal content) lysine, arginine, glutamic acid, methionine, and hydroxyproline were anti‐oxidant with protection factors of up to 1.85. Chelation of metals by amino acids was presumably responsible for the antioxidant activity. The increase in cysteine concentration up to 1% has more than doubled the protection factor in Bint oil (compared with the 0.01% level), whereas with some other amino acids the increase was either small or slight.
Modification of sal fat (shorea robusta) and mowrah fat (madhuca latifolia) by methyl ester‐triglyceride interchange reactions
Authors: Bhattacharyya D. K. , Banerjee K. 
Published: February 2008

AbstractMethyl ester‐triglyceride interchange reactions provide a convenient route for preparing palmitic and lauric acid‐rich Sal fat, and stearic and palmitic acid‐rich Mowrah fat, with altered triglycéride com‐positions and thermal properties. The products are new kinds of plastic fats and may be useful as extenders of cocoa butter, high stability bakery fat, vanaspati (unhydrogenated type), tropical margarine, etc.
Derivatization of keto fatty acids: II. synthesis of long‐chain enolacetates
Authors: Siddiqi S. F. , Ahmad Fasih , Siddiqi M. S. , Osman S. M. 
Published: February 2008

AbstractLong‐chain enolacetates were prepared by refluxing the keto fatty acids with acetic anhydride andp‐toluene sulfonic acid (p‐TSA). 10‐Oxoundecanoic and 2‐oxohexadecanoic acids gave mainly 10‐acetoxy‐10‐undecenoic and 2‐acetoxy‐2‐hexadecenoic acids, respectively. On the other harld, 12‐oxooctadecanoic acid on similar treatment was assumed to yield an isomeric mixture of 12‐acetoxy‐12(11)‐octadecenoic acids. The structure of the individual reaction products were established by spectral studies.
Sucrose esters and sucrose ester/glyceride blends as emulsifiers
Authors: Gupta R. K. , James K. , Smith F. J. 
Published: February 2008

AbstractThe sucrose mono‐and diesters of long‐chain fatty acids form a class of food‐grade emulsifiers with a wide range of hydrophile‐lipophile balance (HLB) values. Blends of sucrose mono‐_and di‐tallowate show a linear relationship between HLB and composition over the HLB range 10–16. Using blends of mixed glycerides and sucrose tallowate, the HLB range from 4 to 16 can be covered. The relationship between HLB water‐solubility and composition in the sucrose esters is dependent on three factors: (a) the degree of sub‐stitution; (b) the alkyl chain length in the ester group; and (c) the presence of dienoic or trienoic acyl groups. Water‐solubility of the esters studied ranged from soluble to insoluble; sucrose esters with C12 or unsaturated acyl groups act as solubilizers. The relationship between fatty acid profile and solubility was studied using sucrose esters prepared from tallow, palm kernel oil, soybean oil and coconut oil. The properties required of a range of emulsifiers designed for use in foods, cosmetics and pharmaceuticals are: (a) that they cover the range of HLB from 2 to 16+; (b) that at high HLB values (16+), they act as solubilizers; (c) low toxicity and irri‐tancy. The sucrose esters, and sucrose ester/mixed glyceride blends, have the required combination of properties. The HLB range to 16+ can be covered without forming ethoxylated or propoxylated derivatives.
Safety of Alpha Olefin Sulfonates
Authors: Haar Gary Ter 
Published: February 2008

AbstractAlpha olefin sulfonates (AOS) belong to the anionic surfac‐tant class. They are efficient, readily biodegradable cleaning agents. This paper reviews the safety aspects of AOS, in‐cluding acute toxicity, teratogenicity, animal sensitization, human sensitization, chronic toxicity and lifetime studies ‐cancer bioassay.
Membrane Lipid Composition Plays a Central Role in the Maintenance of Epithelial Cell Adhesion to the Extracellular Matrix
Authors: Márquez María Gabriela , Leocata Nieto Francisco , Fernández‐Tome María C. , Favale Nicolás Octavio , Sterin‐Speziale Norma 
Published: February 2008

AbstractFocal contacts (FC) are membrane‐associated multi‐protein complexes that mediate cell‐extracellular matrix (ECM) adhesion. FC complexes are inserted in detergent‐resistant membrane microdomains enriched in phosphatidylinositol‐4,5‐bisphosphate (PtdIns(4,5)P2); however, the influence of membrane lipid composition in the preservation of FC structures has not been extensively addressed. In the present work, we studied the contribution of membrane lipids to the preservation of renal epithelial cell adhesion structures. We biochemically characterized the lipid composition of membrane‐containing FC complexes. By using cholesterol and PtdIns(4,5)P2 affecting agents, we demonstrated that such agents did not affect any particular type of lipid but induced the formation of new FC‐containing domains of completely different lipid composition. By using both biochemical approaches and fluorescence microscopy we demonstrated that phospholipid composition plays an essential role in the in vivo maintenance of FC structures involved in cell‐ECM adhesion.