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151.
Sabina Alazzawi 《Letters in Mathematical Physics》2013,103(1):37-58
Considering the model of a scalar massive Fermion, it is shown that by means of deformation techniques it is possible to obtain all integrable quantum field theoretic models on two-dimensional Minkowski space which have factorizing S-matrices corresponding to two-particle scattering functions S 2 satisfying S 2(0) = ?1. Among these models there is for example the Sinh-Gordon model. Our analysis provides a complement to recent developments regarding deformations of quantum field theories. The deformed model is investigated also in higher dimensions. In particular, locality and covariance properties are analyzed. 相似文献
152.
Eduardo López-López Federico J. Sabina Raúl Guinovart-Díaz Julián Bravo-Castillero Reinaldo Rodríguez-Ramos 《Journal of Electrostatics》2013,71(4):791-800
Simple closed-form expressions for effective permittivity of fiber-reinforced composites with transversely isotropic constituents are found using asymptotic homogenization. Circular cylindrical fibers are distributed in a square array. The analysis considers four orientations of constituents transverse symmetry axis relative to fibers direction. Local problems defined on a periodic square unit cell are solved by means of complex potential theory using Weierstrassian and Natanzon's functions, assuming that the contrast of permittivities is small. Derived closed-form formulas are compared with finite element calculations and, in the isotropic case, with standard mixture rules and classical bounds, obtaining excellent results even when contrast is large. 相似文献
153.
Strano-Rossi S Anzillotti L Castrignanò E Felli M Serpelloni G Mollica R Chiarotti M 《Analytical and bioanalytical chemistry》2011,401(2):609-624
An ultra-high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry method for the direct analysis
in oral fluid (OF) of several abused drugs and metabolites in a single chromatographic run was set up and validated. Amphetamine,
methamphetamine, morphine, O-6-monoacetylmorphine, cocaine, codeine, methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine, methylenedioxyamphetamine,
methadone, benzoylecgonine (BEG), Δ9-tetrahydrocannabinol (THC), ketamine, and cocaethylene were determined in a single chromatographic
run with no sample pretreatment, after addition of the respective deuterated internal standards. The method was designed to
perform a confirmation analysis on the residual OF samples after the preliminary on-site screening test, and it was applied
on preservative buffers from different devices (Mavand Rapidstat, Concateno DDS, and Greiner Bio-One) or on neat OF samples.
The method was suitable to be applied to the small amounts of sample available for the confirmatory analysis after the preliminary
on-site screening or on undiluted OF samples. Limits of detection varied from 5 (morphine) to 0.2 ng/mL (methamphetamine,
MDMA, BEG, and cocaethylene). The method was linear for all the substances involved, giving quadratic correlation coefficients
of >0.99 in all the different preservative buffers checked. In addition, repeatability and accuracy were satisfactory for
the majority of the substances, except for a few cases. The developed method was subsequently applied to 466 residual samples
from on-site screening performed by police officers. Of these samples, 74 showed the presence of cocaine and metabolites;
THC was detected in 49 samples. Two samples showed codeine and morphine while MDMA was detected in 11 samples and ketamine
in four samples. 相似文献
154.
We prove that Euler’s equation , characterising homogeneous functions, is stable in Hyers–Ulam sense if and only if . 相似文献
155.
Rosanna Toniolo Sabina Susmel Nicolò Dossi Andrea Pizzariello Marzia Martinis Gino Bontempelli 《Electroanalysis》2010,22(6):645-652
A porous gold electrode supported on one face of an ion‐exchange membrane, acting as a solid polymer electrolyte (SPE), is proposed as an amperometric sniffer for monitoring the aldehyde content in the headspace in equilibrium with lipid samples, in order to gain indication of their state of turning rancid It was used as a detector for a flow injection system in which aldehydes were injected, after preconcentration by solid phase microextraction on a SPME fiber from the gas phase standing above thermostated samples and subsequent desorption by heating. Repeatable (±4.5%) sharp peaks were detected over a wide linear concentration range (0.5–200 ppm). A detection limit of about 0.03 ppm was inferred for a signal‐to‐noise ratio of 3, referred to hexylaldehyde (used as prototype) dissolved in squalene or vegetable oils samples. This approach was applied to the determination of volatile aldehydes from some partially oxidized cereal oils and the results found were compared with both the corresponding peroxide values and their aldehyde content determined by a conventional spectrophotometric method. 相似文献
156.
Patel Sanjay V. Hobson Stephen T. Cemalovic Sabina Mlsna Todd E. 《Journal of Sol-Gel Science and Technology》2010,53(3):673-679
The responses of alkylamine functionalized organic bridged polysilsesquioxanes on chemicapacitive sensors to carbon dioxide
(CO2) are described operating at temperatures ranging from 15 to 50°C. These hybrid organic–inorganic network materials were synthesized
by the sol–gel polymerization of a mixture of a matrix monomer and functional monomer at various ratios followed by aging
and ink-jet deposition of the sol on each capacitive sensor. During exposure of the sensor to known concentrations of analyte,
the material’s capacitance was measured. From these changes in capacitance, detection limits ranging from 40 to 100 ppm were
calculated. Furthermore, a correlation was observed with increasing length of the alkyl chain in the amine monomer correlating
with an increase in CO2 sensitivity and a decrease in water sensitivity. These materials offer a new method for CO2 detection for building control systems or other low-power applications using low operating temperatures. 相似文献
157.
158.
Aliev Ziya Sakhaveddin Musayeva Sabina Sahib Imamaliyeva Samira Zakir Babanly Mahammad Baba 《Journal of Thermal Analysis and Calorimetry》2018,131(2):1115-1123
Journal of Thermal Analysis and Calorimetry - A combination of sol–gel Pechini method and flame synthesis was used to prepare yttrium aluminate glass microspheres with the garnet composition... 相似文献
159.
160.
Wydro P Knapczyk S Lapczyńska M 《Langmuir : the ACS journal of surfaces and colloids》2011,27(9):5433-5444
In this work, we have investigated the condensing and ordering effect induced by cholesterol on phosphatidylcholines (PCs). To perform the studies systematically, for the experiments we have selected phospholipids differing only in the number of cis monounsaturated chains (1,2-distearoyl-sn-glycero-3-phosphocholine--DSPC, 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine--SOPC, 1,2-dioleoyl-sn-glycero-3-phosphocholine--DOPC) or in the length (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine--POPC vs SOPC) of sn-1 acyl chain. Because the cholesterol concentration in mammalian membranes can be as high as 70 mol % of total lipids, the investigations were performed in a wide range of the sterol content. The results of the Langmuir monolayer experiments evidence that the relation between the structure of hydrophobic part of PC and the magnitude of the effects induced by cholesterol found at lower sterol content is different from that observed at higher sterol concentration. At a lower concentration of sterol (up to 30%), the condensing effect of cholesterol is stronger on saturated DSPC than on PCs containing monounsaturated chain(s), which is consistent with the conclusions drawn by other authors. However, at higher sterol content (≥50%), saturated DSPC is less susceptible to the influence of sterol than the investigated unsaturated PCs. To explain these irregularities, we have considered the strength of van der Waals interactions as well as the influence of sterol on the tilt of polar heads of PCs. It was also found that in the whole range of sterol concentration the ordering effect is stronger on saturated DSPC as compared to unsaturated phospholipids. However, at lower sterol content (up to 30%) the ordering effect induced on unsaturated PCs is rather weak, and the ordering does not change drastically in comparison with pure PCs film. 相似文献