bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diode characterization in a coaxial mount
Authors: Steer Michael B. 
Published: July 2007

AbstractA previously presented technique for experimentally characterizing packaged microwave diodes mounted in a coaxial test fixture is investigated. It is demonstrated that the fields surrounding the diode and the calibration packages are adequately developed to provide an accurate diode equivalent circuit model for use in computer‐aided design. © 1993 John Wiley & Sons, Inc.
Design of a log periodic strip grating microstrip antenna
Authors: Delyser Ronald R. , Chang David C. , Kuester Edward F. 
Published: July 2007

AbstractThe design of a log periodic strip grating antenna is described. The 12‐element antenna is compact and has a measured power bandwidth of 22%. The antenna elements are mounted on the top of the top layer of a two‐layer structure with its feed line located between the two dielectric layers providing electromagnetic coupling. The structure was analyzed using PMESHD, a moment method code for two‐layer passive structures. The analysis and measurements are in good agreement. © 1993 John Wiley & Sons. Inc.
Unified treatment of scalar and vector potential fields with lorentz gauge condition by spatial network expression (invited article)
Authors: Yoshida Norinobu 
Published: July 2007

AbstractIn the analysis of electromagnetic fields, the vector potential has important roles especially when sources exist and quantum effects occur. We have recently proposed a new numerical method for vector analysis of three‐dimensional electromagnetic fields in the time domain. This is known as the Spatial Network Method (SNM). I have already shown that SNM can be expanded to the vector potential fields with Coulomb's gauge condition by using not only the magnetic vector potential but also the electric vector potential. In this article, the unified formulation in the spatial network expression for both the vector potential and the scalar potential fields is proposed by using the Lorentz gauge condition including loss term. In the formulation, new “F” and “F*” variables are defined to utilize the correspondence between the electromagnetic scalar potential and the velocity potential in the acoustic field. As an example, the difference of internal magnetic fields in the substance with perfect conductivity or perfect diamagnetism in the scalar magnetic field is simulated. © 1993 John Wiley & Sons, Inc.
The transmission line models: Past, present, and future (invited review article)
Authors: Vandenbosch G. A. E. , Demuynck F. J. , Van de Capelle A. R. 
Published: July 2007

AbstractIn this article, an overview will be given on the continuous improvement of the transmission line models, one of the different types of models used to analyze microstrip antenna structures. Starting from 1974, the year in which the simplest possible variant was introduced, the different improvements will be discussed briefly from a pragmatic point of view. More time will be devoted to a state‐of‐the‐art transmission line model. The last part of this review article will take a look into the future and try to guess which improvements and generalizations can (and maybe have to) be implemented to obtain a model able to compete with sophisticated integral equation models running on ever faster and faster computers. © 1993 John Wiley & Sons, Inc.
A simple and accurate model for the resonant frequency and the input impedance of printed antennas
Authors: Damiano J. P. , Papiernik A. 
Published: July 2007

AbstractWe propose an analytical model for the determination of the electrical characteristics (resonant frequency, input impedance) of probe‐fed printed antennas with radiating element of various form. This model is original and is easily included in CAD system. The theoretical results are in good agreement with the experiments and with rigorous theoretical models. We make use of computer algebra to compute the uncertainty of the calculated values, i.e., the sensitivity to the physical and geometrical parameters. © 1993 John Wiley & Sons, Inc.
Computer‐aided analysis of microstrip antennas employing parasitic elements
Authors: Hayirlioǧlu Lale , Birand M. Tuncay 
Published: July 2007

AbstractThe moment method in the spectral domain is used to perform a computer‐aided analysis of printed antenna structures employing tuning stubs and electromagnetically coupled patches. Variation of the input VSWR versus frequency is obtained and the radiation patterns are plotted for various antenna configurations. Surface wave coupling effects are investigated. © 1993 John Wiley & Sons, Inc.
Mixed‐potential integral equation (MPIE) formulation for nonplanar microstrip structures of arbitrary shape in multilayered uniaxial media (invited article)
Authors: Michalski Krzysztof A. 
Published: July 2007

AbstractA straightforward derivation is presented of three distinct mixed‐potential integral equations (MPIEs) that are well‐suited for the analysis of arbitrarily shaped, planar or nonplanar microstrip structures in multilayered, planar, uniaxially anisotropic media of infinite lateral extent. © 1993 John Wiley & Sons, Inc.
Agronomic, chemical and genetic profiles of hot peppers (Capsicum annuum ssp.)
Authors: De Masi Luigi , Siviero Pietro , Castaldo Domenico , Cautela Domenico , Esposito Castrese , Laratta Bruna 
Published: July 2007

AbstractA study on morphology, productive yield, main quality parameters and genetic variability of eight landraces of hot pepper (Capsicum annuum ssp.) from Southern Italy has been performed. Morphological characters of berries and productivity values were evaluated by agronomic analyses. Chemical and genetic investigations were performed by HPLC and random amplified polymorphic DNA (RAPD)‐PCR, respectively. In particular, carotenoid and capsaicinoid (pungency) contents were considered as main quality parameters of hot pepper. For the eight selected samples, genetic similarity values were calculated from the generated RAPD fragments and a dendrogram of genetic similarity was constructed. All the eight landraces exhibited characteristic RAPD patterns that allowed their characterization. Agro‐morphological and chemical determinations were found to be adequate for selection, but they resulted useful only for plants grown in the same environmental conditions. RAPD application may provide a more reliable way based on DNA identification. The results of our study led to the identification of three noteworthy populations, suitable for processing, which fitted into different clusters of the dendrogram.
Effect of lumbar‐epidural administration of tramadol on lower urinary tract function
Authors: Singh S.K. , Agarwal M.M. , Batra Y.K. , Kishore A.V.K. , Mandal A.K. 
Published: July 2007

AbstractAimsIntrathecal and epidural administration of µ‐agonist opioids is associated with urinary retention, a potentially serious adverse‐event. In animal studies tramadol has been found not to affect voiding function. We evaluated urodynamic effects of epidural tramadol in humans.MethodsFifteen adults planned for cystoscopy under local‐anesthesia underwent urodynamics (UDS) at baseline and 30 min after administration of 100 mg tramadol in lumbar‐epidural space. UDS consisted of filling cystometry, pressure‐flow study and pelvic floor electromyography (EMG). Subsequently, all underwent cystoscopy and were observed for 6 hr.ResultsAfter injection of tramadol, a significant rise was observed in bladder capacity (391.8 ± 179.6 ml vs. 432.7 ± 208.8 ml; P = 0.019) and compliance (60.1 ± 51.5 ml/cm H2O vs. 83.0 ± 63.0 ml/cm H2O; P = 0.011) without a significant change in filling pressure (22.5 ± 13.2 cm H2O vs. 24.1 ± 15.1 cm H2O; P = 0.576). Filling sensations were delayed significantly (P ≤ 0.05). EMG during filling phase showed a significant fall (P = 0.027). Peak flow‐rate (Qmax), average flow‐rate, postvoid residue and detrusor pressure‐at‐Qmax did not show significant change from baseline (P > 0.05). Three patients had bladder outlet obstruction which did not worsen after the injection. Guarding reflex was inhibited in seven out of 12 patients who had it at baseline (P = 0.016).ConclusionsEpidural tramadol increases the bladder capacity and compliance and delays filling‐sensations, without ill effect on voiding. This seems true even for patients with obstructed outflow; however, due to small number of patients a definite conclusion cannot be derived. These results will guide clinician to avoid catheterization in cases where epidural tramadol is used for postoperative pain. The inhibitory effects of tramadol on EMG activity are intriguing and need further studies. Neurourol. Urodynam. © 2007 Wiley‐Liss, Inc.
Numerical study of natural convection in a cavity of high aspect ratio by using the lattice Boltzmann method
Authors: Jami Mohammed , Amraqui Samir , Mezrhab Ahmed , Abid Cherifa 
Published: July 2007

AbstractA comprehensive numerical study has been conducted to investigate two‐dimensional, steady heat transfer of natural convection in a divided enclosure of high aspect ratio. The vertical walls of the enclosure are maintained at different temperatures, while the horizontal walls are adiabatics. A numerical hybrid scheme with lattice Boltzmann for fluid velocity and finite difference for the temperature is adopted. Parametric studies of the effects of aspect ratio, number and length of partitions attached to the cold wall of the enclosure on heat transfer and fluid flow have been
performed. Copyright © 2007 John Wiley & Sons, Ltd.
Alternating copolymers of electron‐rich arylamine and electron‐deficient 2,1,3‐benzothiadiazole: Synthesis, characterization and photovoltaic properties
Authors: Huo Lijun , He Chang , Han Minfang , Zhou Erjun , Li Yongfang 
Published: July 2007

AbstractA series of alternating copolymers of electron‐rich arylamine and electron‐deficient 2,1,3‐benzothiadiazole (BT), PV‐BT, DP‐BT, and TP‐BT, were synthesized by Heck coupling reaction. UV–vis absorption and fluorescence spectra show that the copolymerization of electron‐rich diphenylamine (DP), triphenylamine (TP), MEH‐PV (PV), and electron‐deficient BT results in low‐bandgap conjugated polymers. Within the three copolymers of PV‐BT, DP‐BT, and TP‐BT, TP‐BT possesses the highest hole mobility of 4.68 × 10− 5 cm2/V, as determined from the space charge limited current (SCLC) model. The bulk heterojunction‐typed polymer solar cells (PSCs) were fabricated with the blend of the copolymers and PCBM as the photosensitive layer. The power conversion efficiencies (PCE) of the PSCs based on PV‐BT, DP‐BT, and TP‐BT reached 0.26%, 0.39%, and 0.52%, respectively, under the illumination of AM 1.5, 100 mW/cm2. The results indicate that TP‐BT is a promising photovoltaic polymer for PSCs. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3861–3871, 2007
2,4,6‐trichlorophenyl acrylate emulsion‐templated porous polymers (PolyHIPEs). Morphology and reactivity studies
Authors: Leber Nermina , Fay Jonathan D. B. , Cameron Neil R. , Krajnc Peter 
Published: July 2007

AbstractA series of monolithic crosslinked polymers with 2,4,6‐trichlorophenyl acrylate as a reactive component was prepared by free radical polymerization of the internal phases of high internal phase emulsions (HIPEs). The volume ratio of water to oil phase (void volume; 60–90%), crosslinker type (divinylbenzene or ethylenglycol dimethacrylate) and quantity (30–50 mol %) and type of porogenic solvent (chlorobenzene, toluene, chloroform, dichloroethane) were altered to study these effects on the structure and reactivity of the monolithic polymers. The polymer supports were characterized by scanning electron microscopy (SEM), FTIR spectroscopy, elemental analysis and mercury intrusion porosimetry. SEM images revealed an open cellular structure with voids between 1 and 12 μm and window sizes between 0.3 and 3 μm. The porogen had an influence on the surface area, being larger with added porogen and the influence being highest with toluene. Adding toluene also influenced the void size, increasing the average diameter from ∼2 μm (no porogen) to ∼12 μm (added toluene). Monolithic supports were functionalized by reaction of the ester moieties with tris(2‐aminoethyl)amine derivative and by hydrolysis of the ester groups to carboxylic acids. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4043–4053, 2007
Systematic study of the fluorescence decays of amino‐coumarin dyes in polymer matrices
Authors: Felorzabihi Neda , Haley Jeffrey C. , Bardajee Ghasem R. , Winnik Mitchell A. 
Published: July 2007

AbstractWe measured the fluorescence decays of seven different amino‐coumarin dyes in polymer films of poly(methyl methacrylate) (PMMA), poly(styrene) (PS), and ethylene‐butene rubber (EBR); as well as in the small molecule analogs ethyl acetate and toluene. Many of the dye‐solvent and dye‐polymer combinations exhibited single exponential decays with lifetimes ranging from 2.3 to 3.9 ns. Small deviations from single exponential behavior occurred for most of the dyes in EBR. Significant deviations from single exponential behavior occurred for 7‐(diethylamino)‐2‐oxo‐2H‐1‐benzopyran‐3‐carboxylic acid (coumarin‐3) in ethyl acetate and in all polymer matrices and 2,3,6,7‐tetrahydro‐11‐oxo‐1H,5H,11H‐[1]benzopyrano[6,7,8‐ij]quinolizin‐10‐carboxylic acid (coumarin‐343) in all of the polymer matrices. Time‐resolved fluorescence spectra indicated the presence of two different excited states for coumarin‐3 and coumarin‐343 in PMMA; these spectra were qualitatively different from the time‐resolved spectra of coumarin‐3 in ethyl acetate. We rationalize these results in terms of the chemical functionalities of the various dyes. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2333–2343, 2007
Effect of Grinding Media Shapes on Breakage Parameters
Authors: Ipek Halil 
Published: July 2007

AbstractIn the present study, the effect of grinding media shape on breakage parameters was investigated. Balls and cylpebs were used as the grinding media. It was observed that the grinding of quartz obeyed first‐order breakage kinetics in the case of balls and cylpebs. Higher breakage rates were noted with cylpebs than with balls. Furthermore, it was found that the primary breakage distribution function is dependent on the feed size (i.e., non‐normalizable), but independent of the grinding media shape. The effect of grinding time on the product size distribution has also been investigated. Following four and ten minute grindings, cylpebs produced a relatively finer product compared to balls.
S100A8, S100A9, and the S100A8/A9 complex in circulating blood are not associated with prostate cancer risk—A re‐evaluation study
Authors: Ludwig Stefan , Stephan Carsten , Lein Michael , Loening Stefan A. , Jung Klaus 
Published: July 2007

AbstractBACKGROUNDTo evaluate the diagnostic performance of plasma S100A8, S100A9, and the S100A8/A9 complex as novel markers to discriminate between benign and malignant prostatic diseases as recently suggested for S100A9.METHODSThe study included 90 prostate cancer (PCa) patients (pN0M0, n = 50; pN1M0, n = 27; M1, n = 13), 50 controls without PCa, and six patients within 72 hr after radical prostatectomy for repeated measurements. The S100 proteins were analyzed with specific ELISAs. Comparisons were made to the prostate‐specific antigen (tPSA) and the ratio of free to tPSA (%fPSA).RESULTSThe plasma concentrations of the S100 proteins in controls had either significantly higher values (S100A8; P = 0.020) or the tendency to higher values compared with the results in PCa patients. Differences between the three PCa groups were almost negligible. No correlation could be found between S100 protein levels and PSA concentration (rs = −0.110 to 0.433, P = 0.317–0.433) or prostate volume (rs = −0.038 to 0.018, P = 0.676–0.844). Tumor stage and tumor grade had no observed effect on S100 protein concentrations. After prostatectomy, there were discordant elimination kinetics for PSA and the S100 proteins, as the S100 proteins partially increased while PSA continuously decreased. Analyses of receiver‐operating curves showed that, compared with PSA, S100A8, S100A9, and S100A8/A9 did not improve the differentiation between patients with and without PCa, while the discrimination ability was significantly lower than that of %fPSA.CONCLUSIONSOur re‐evaluation study showed that S100A8, S100A9, and the complex S100A8/A9 were less indicative than %fPSA and that they are not suitable to replace PSA. Prostate 67: 1301–1307, 2007. © 2007 Wiley‐Liss, Inc.
Photostructural transformations in amorphous chalcogenide semiconductors
Authors: Shpotyuk O. I. 
Published: July 2007

AbstractThe mechanism of photoinduced structural transformations in amorphous As2S3 is studied with the differential IR Fourier spectroscopy technique in the 400 to 100 cm−1 region. It is established that the irreversible photostructural effect observed in freshly evaporated thin films is accompanied by switching of homopolar chemical bonds into heteropolar ones. The stage of reversible photodarkening is realized in a‐As2S3 samples after a first cycle of photoexposure and thermoannealing. The corresponding destruction‐polymerization reaction is opposite to that obtained for irreversible changes. The whole scheme of photo‐ and thermoinduced structural transformations in a‐As2S3 is presented as a multicyclic process of coordination defect formation and annihilation.
Application of a model of interacting atomic chains for the description of edge dislocations
Authors: Landu A. I. 
Published: July 2007

AbstractAn extension of a previous work is presented in which a theoretical model of interacting atomic chains (IACs) was proposed which represents a multi‐dimensional (two‐ or three‐dimensional) generalization of the classical Frenkel‐Kontorova (discrete sine‐Gordon) model. The previous paper considered the application of the IACs model to the description of the crowdion in anisotropic crystals. Now we prove that this model can be used for computer simulations of edge dislocations. The computer calculated data agree well with analytical results of elasticity theory. The IACs model is compared to other theoretical models proposed in the literature to describe dislocations in the crystal.
Intersubband coulomb scattering effecton high‐field hot‐electron transport in a quantum wire
Authors: Wu M. W. , Yu Z. G. , Lei X. L. 
Published: July 2007

AbstractHot‐electron transport properties of AlxGa1−xAs/GaAs quantum wires under high electric fields are studied by means of the balance‐equation approach using a model with multiple species of carriers. Each transverse subband is assumed to have its own electron temperature, Fermi level, and mean drift velocity differing from other nondegenerate subbands. The intersubband Coulomb interactions are taken into account perturbatively for the first time together with acoustic and polar optic phonon scatterings in the numerical calculation. Our calculation shows that although the electron temperatures, Fermi levels, and drift velocities of different subbands differ markedly from each other, the overall average drift velocity and the resultant nonlinear mobility are very close to those predicted by the conventional model assuming single species of carriers in the multisubband quantum wire system.
Computer Simulation of Point Defects at Finite Temperatures
Authors: Monti A. M. 
Published: July 2007

AbstractA self‐consistent calculation method based on conjugate gradients is applied to obtain the atomic structure and thermodynamic properties of microstructural defects in solids at finite temperatures. The lattice free energy, described in the local harmonic approximation, consists of two contributions: static and vibrational. The former depends on the atomic coordinates, which change with thermal expansion. The latter explicitly depends on temperature and frequencies of the normal modes. Frequencies, obtained in an Einstein‐type approximation, are implicit functions of atomic coordinates, therefore they may also change with thermal expansion. The formation free energy for self‐interstitials and vacancy‐type defects is calculated for Cu over the broad temperature range 0 to 1200 K. A remarkable decrease of the formation free energy with temperature increase is observed. Such decrease is near 20% for vacancy‐type defects and 35% for self‐interstitials, over the whole temperature range.
Electronic and Crystal Structure of the ZrCu Intermetallic Compound Close to the Point of Structural Transformation
Authors: Zhalko‐Titarenko A. V. , Yevlashina M. L. , Antonov V. N. , Yavorskii B. Yu. , Koval Yu. N. , Firstov G. S. 
Published: July 2007

AbstractIt is found that cooling of the B2 high‐temperature phase of ZrCu above the martensitic transition (MT) point is not accompanied by essential changes of its electronic structure. MT in ZrCu is realized generally by the formation of two monoclinic martensites with positive volume effect. The electronic structure of the B2 phase of ZrCu demonstrates a sharp peak of the electron density of states just above the Fermi level, which plays a stabilization role related to the shear deformation above MT. This stabilization effect rapidly weakens on cooling and can be the possible origin of the lattice instability of the high‐temperature B2 phase of the ZrCu intermetallic compound.
Dominant Traps in Liquid Phase Epitaxial GaAs Studied by Controlled Doping with Indium and Antimony
Authors: Mallik K. , Dhar S. 
Published: July 2007

AbstractPhotocapacitance measurements in the photon energy range of 0.64 to 1.27 eV are done on GaAs layers grown by liquid phase epitaxy (LPE) and doped with varying amounts of indium (In) and antimony (Sb). Two hole traps with optical ionization energies of 0.65 and 0.79 eV are revealed in the material which are assumed to be two levels associated with the hole trap B reported in the literature. In addition, the hole trap A, usually found in LPE GaAs is also detected here by optical deep level transient spectroscopy (ODLTS) technique. The results of trap density measurements, as functions of isoelectronic doping concentration, indicate that VGa is an active constituent of the hole traps in LPE GaAs. The concentration of the 0.79 eV trap is found to be reduced in the material with high concentration of Sb. The analysis of photocapitance data using the existing theoretical models indicates the presence of an electron trap with activation energy of 0.75 eV in the heavily Sb‐doped material. This trap may be identified with the second charge state of the SbGa electron trap, obtained previously in bulk and metalorganic vapor phase epitaxial GaAs doped with Sb. The sharp reduction of the 0.79 eV hole trap density in Sb‐doped materials is explained by assuming the complex GaAsV, as its source.
Phonons in F.C.C. Thorium
Authors: Verma M. L. , Rathore R. P. S. 
Published: July 2007

AbstractThe generalized form of the exponential potential is suitably extended to account for a) a realistic realization of interactions at small separations, b) embodying three‐body and electronic effects into the interaction through the parameters n and m, respectively, in an alternative and simpler form, c) a model free from the usual fitting procedure. The efficacy of the potential known as extended generalized exponential potential (EGEP) so developed is employed to compute the phonon dispersion in thorium. The predictions show good agreement with experimental findings.
Electromagnetic Properties of a Type‐II Superconducting Rotating Cylinder
Authors: Saif A. G. , Refai T. F. , El‐Sabagh M. A. 
Published: July 2007

AbstractThe electromagnetic field distributions and solutions for an infinitely long superconducting cylinder rotating about its axis and placed parallel to an infinitely long normal conducting wire carrying an alternating current are obtained. The propagation behavior of the fields within the cylinder are investigated in terms of the propagation constant as a function of the London penetration depth. The power loss and the torque on the cylindrical surface are calculated. Satisfactory agreement with previous results is achieved.