bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of Organoiron Macromolecules Based on Upper Rim Functionalized Calix[4]arenes
Authors: Abd‐El‐Aziz Alaa S. , Shipman Patrick O. , Shipley Paul R. 
Published: December 2009

AbstractThe versatility of cationic cyclopentadienyliron complexes is demonstrated for the generation of calix[4]arene‐based dendrimers and polymers. Dendrimers were prepared from a branched organoiron calix[4]arene through subsequent reactions of azo dyes and organoiron complexes. The resulting azo dye‐containing metallocalix[4]arenes were soluble in polar organic solvents and displayed λmax ranging between 430 and 456 nm. Upon addition of various acids, the λmax shifted to higher wavelengths (513–535 nm). In the solid state and in solution, the azo dye‐containing metallocalix[4]arenes reversibly changed colour in the presence of acid and base, indicating their potential use as acid sensors. Cyclic voltammetric studies showed that the iron centres of the metallocalix[4]arenes were reversibly reduced at E1/2 = −1.49 V. When non‐branching organoiron‐based calix[4]arene were reacted with dithiols, polymers containing calix[4]arenes either in their side chains or main chains were obtained. The polymers possessed weight average molecular weights between 35 000 and 53 000. The polymers were determined to be thermally stable with backbone decomposition occurring above 500 °C.magnified image
A novel notch waveguide filter
Authors: Prikolotin Sergey A. , Kirilenko Anatoliy A. 
Published: December 2009

AbstractThe simple configurations of realistic rejection units placed in a rectangular waveguide are suggested. They are thin stepped conductors connecting the opposite waveguide walls and forming a kind of thin two‐aperture irises easily placed, for example, between waveguide flanges. A rejection phenomenon is based on the interference of the eigenoscillation fields of the iris with two L‐shaped apertures. The rejection frequency and quality factor are controlled over a wide range by the placement and the height of the conductor step. The situation when a stepped perfect conductor provides the resonance of a nearly zero bandwidth is revealed. In other words, such a nontrivial 3D waveguide unit loaded with above‐cutoff waveguides is able to support an eigen oscillation without any radiation loss. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 416–420, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24892
Determination of resonant frequency of slot‐loaded rectangular microstrip patch antennas
Authors: Neog Dipak Kr. , Devi Reeta 
Published: December 2009

AbstractA generalized method is presented to determine the resonant frequency of slot‐loaded rectangular microstrip patch antenna by equating its area to an equivalent area of a rectangular microstrip patch antenna. The computed results are in good agreement with the reported simulated and measured results. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 445–448, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24901
Rectangle waveguide to substrate integrated waveguide transition and power divider
Authors: Li Chao , Wu Di , Seo Kazuyuki 
Published: December 2009

AbstractA novel Ku‐band transition and power divider between rectangle waveguide (RWG) and substrate integrated waveguide (SIW) is proposed. This transition and power divider is realized by a radiating metal patch located on the backside of a middle dielectric substrate and a coupling aperture etched on the SIW's ground plane. The transition and power divider is studied both simulatively and experimentally. As reported, low insertion loss of not higher than 0.6 dB and good return loss of −15 dB may be achieved at the frequency range of 12.1–12.8 GHz. The method to increase the bandwidth is investigated. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 375–378, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24902
High eye‐quality improvement by a single‐SOA regenerative wavelength converter
Authors: Ribeiro Napoleão S. , Gallep Cristiano M. , Conforti Evandro 
Published: December 2009

AbstractA simple all‐optical cross‐gain modulation (XGM) wavelength conversion scheme based on a single semiconductor optical amplifier with higher regeneration capabilities is presented. A proof of concept was performed at data rates from 0.6 to 13.5 Gbps for NRZ streams using the KyaTera/FAPESP buried fiber optical testbed. Good results were obtained for large lambda‐detuning (>10 nm), including conversion to the same wavelength. The best experiments achieved an improvement in the quality factor (Q‐factor) over 4 units with input signals deteriorated by the standard fiber dispersion, with an extinction ratio penalty of 1.5 dB. In addition, the converter presented a small dependence with the relative optical input signal polarization (around 1dB). © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 441–445, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24906
Scattering of a special class of isorefractive spherical objects with spherical anisotropy
Authors: Xue Jing , Lee Hyue 
Published: December 2009

AbstractThe isorefractive scattering by spherically anisotropic spheres is established for the plane‐wave incidence. The effects of the anisotropy ratio in the scattering cross‐sections are studied, and physical insights to particular phenomena are provided. The equivalence in the far‐field scattering is also revealed for both isorefractive and spherically uniaixal anisotropic spheres. The peculiarities in the scattering for both small and large anisotropic spheres and the dependence on spherical anisotropy are presented and discussed. The method developed here thus possesses higher degree of generality and applicability, which can study scattering problems of anisotropic bodies as well as model some physical problems. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 334–338, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24911
Three antenna array design for buried object detection
Authors: Ghosh Debalina , Sarkar Tapan K. 
Published: December 2009

AbstractAn impulse radiating GPR system is designed with resistively loaded antennas, which are placed in an array configuration to cancel ground bounce and antenna coupling effects. The target response is isolated through deconvolution by the conjugate gradient method. By applying the matrix pencil method to the late time response the natural resonant frequencies of the target are extracted for identification. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 338–343, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24912
Double‐printed rectangular patch dipole antenna with band‐notched function for UWB communications
Authors: Xiao Jin‐Xiang , Wang Mei‐Fang , Li Guo‐Jian 
Published: December 2009

AbstractA novel double‐printed rectangular patch dipole antenna with a band‐notched function suitable for UWB application is presented and investigated in this article. The band‐notched characteristic is achieved by connecting L‐shaped strips to the antenna rather than inserting slot to the antenna. The measured results show that the frequency band of VSWR < 2 covers 3.1 to 10.6 GHz UWB band, whereas the notched‐frequency range is 5.05–6.1 GHz which covers 5GHz WLAN band of 5.15–5.825 GHz. Transfer function and time domain characteristics are also studied in this article. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 269–272, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24921
Nonlinear behavioral of GaN Doherty power amplifiers using neural modeling
Authors: Liu Haiwen 
Published: December 2009

AbstractA radial‐basis function neural network (RBFNN) approach is proposed for predicting the nonlinear behaviors of gallium nitride (GaN) Doherty amplifier. Sampled input and output data from a designed GaN Doherty amplifier were used to train and test the proposed RBFNN model. Comparison of amplitude modulation to amplitude modulation (AM/AM), amplitude modulation to phase modulation (AM/PM), gain, power added efficiency (PAE) and output power (Pout) curves among the RBFNN method, circuit simulation and measurement are given. The results indicate that the proposed RBFNN model can reproduce the nonlinear characteristics of the designed GaN Doherty amplifier accurately. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 307–309, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24924
Experimental and numerical investigation of a magnetic resonator antenna based on the M‐type hexaferrite (BaxSr1−xFe12O19)
Authors: Pereira F. M. M. , Sohn R. S. T. M. , Rodrigues H. O. , Júnior G. F. M. P. , Theophilo K. R. B. , Rocha M. J. S. , Silva M. A. S. , Sombra A. S. B. 
Published: December 2009

AbstractIn this work is reported an experimental and numerical investigation of magnetic resonator antennas (MRA) of magnetic the alloy BaxSr1−xFe12O19 obtained in a new procedure in the solid‐state method. The experimental and theoretical characteristics of the antenna like return loss, bandwidth, input impedance, and radiation patterns are in good agreement. Numerical validation is done, taking into account the air gaps between the dielectric resonator and the metallic conductors. Frequency response bandwidth in the range of 9–10% was obtained for frequency operation around 4 GHz. The alloys BaxSr1−xFe12O19 showed a dielectric constant around 8, with loss in the range 10−2–10−3. The temperature coefficient of resonant frequency (τf) was also measured for magnetic alloys BaxSr1−xFe12O19. The values obtained were in the range of 44.90–87.83 ppm/°C. These results obtained confirm the potential use of those materials for small dielectric MRA. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 452–458, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24931
A novel reduced λ/4 resonant monopole with associated extra inductance
Authors: Tirado‐Mendez J. A. , Jardon‐Aguilar H. , Flores‐Leal R. , Reyes‐Ayala M. 
Published: December 2009

AbstractIn this article, a novel technique is employed to reduce the dimensions of a λ/4 resonant monopole. The procedure considers the antenna covered by a cylindrical conductor and short‐circuited at the top of the resonator, separated by a dielectric similar to a coaxial line. With this technique, the length of the monopole can be reduced up to40% without modifying, significantly, the parameters of the antenna. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 276–280, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24933
Advantage of a hybrid MoM scheme with approximate Green function to model integrated glass antennas
Authors: Bogdanov Faik G. , Karkashadze David D. , Jobava Roman G. , Gheonjian Anna L. , Yavolovskaya Ekaterina A. , Bondarenko Natalia G. 
Published: December 2009

AbstractA new hybrid MoM scheme with approximate Green function of antenna elements, printed‐on or embedded into the glass, is described. This scheme is used to simulate scattering characteristics of integrated glass antenna models. Comparison with measurement data and with previous modeling techniques for different measurement setups is performed. An advantage of the proposed modeling technique over previous techniques is demonstrated. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 351–354, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24936
Bandwidth enhancement of slot‐fed dielectric resonator antenna
Authors: Madhuri R. G. , Hadalgi P. M. , Mallikarjun S. L. , Malipatil S. A. 
Published: December 2009

AbstractNovel slot‐fed dielectric resonator antenna is studied experimentally. The antenna is comprised of a rectangular dielectric resonator and a mictrostrip fed coupling slot. The multiband resonances of the two radiators i.e., slot and dielectric resonator are combined to extend the antenna bandwidth. Dielectric resonator of three different thicknesses is studied, providing a bandwidth of 49.25%. The radiation patterns are measured and are presented. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 316–318, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24937
Design of DC to 10‐GHz broadband CMOS transmit/receive switch circuits
Authors: Lin Yih‐Hsia , Chu Chun‐Hsueh , Gong Jeng 
Published: December 2009

AbstractThis article presents the design of CMOS transmit/receive (T/R) switch circuits for ultra‐wideband applications. Techniques such as RF floated body to extend the bandwidth and decrease the insertion loss, and stacking architecture to enhance the power handling capability are used for the design of T/R switch circuits on a standard 0.18‐μm triple‐well process. The measurement of the T/R switch circuits demonstrates the effectiveness of the methods presented in this article. Two types of T/R switch circuits are designed and presented in this article. The T/R switch with non‐stacking architecture achieves an insertion loss less than 1.2 dB and an input 1‐dB compression point (IP1dB) of 24 dBm from DC to 10 GHz for. In addition, the T/R switch with stacking architecture exhibits a higher IP1dB of 27 dBm and an insertion loss less than 1.69 dB from DC to 10 GHz. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 322–326, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24948
A wideband digital predistortion for highly linear and efficient GaN HEMT Doherty power amplifier
Authors: Lee Mun‐Woo , Lee Yong‐Sub , Kam Sang‐Ho , Jeong Yoon‐Ha 
Published: December 2009

AbstractIn this article, we propose the wideband digital predistortion (WDPD) for a highly linear and efficient GaN HEMT Doherty power amplifier (DPA). The WDPD is composed of the memory less DPD and the memory system, which compensates for the memory effects to achieve a highly linear wideband performance. The 11th‐memoryless polynomial characterizes the behavioral model of the DPA. The AM/AM and AM/PM lookup tables and the coefficients of the memory system are determined by the Recursive Least Square algorithm. For a 2‐FA WCDMA signal with 10 MHz carrier spacing at 2.14 GHz, the adjacent channel leakage ratio at ±10 MHz offset are improved over −50 dBc without the efficiency degradation at an output power of 36 dBm. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 484–487, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24951
Micro‐coaxial Ka‐band Gysel power dividers
Authors: Saito Yuya , Fontaine Daniel , Rollin Jean‐Marc , Filipovic Dejan S. 
Published: December 2009

AbstractMonolithic, 450‐μm tall, rectangular coaxial Gysel divider is presented in this article. The divider is fabricated by a surface micromachining process with six sequentially deposited copper layers. Athree‐port, resistor‐less divider has overall loss of 0.6 dB at 30 GHz, input port reflection coefficient better than −10 dB, and output amplitude and phase misbalances of ±0.18 dB and ±1.8°, respectively, throughout Ka‐band. The device is designed in a way that permits straightforward realization of a Gysel divider with integrated resistors. Electromagnetic and electrothermal analyses and design of the divider are conducted, and good agreement with measurements is obtained. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 474–478, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.24956
A partition of unity‐based multiscale approach for modelling fracture in piezoelectric ceramics
Authors: Verhoosel Clemens V. , Remmers Joris J. C. , Gutiérrez Miguel A. 
Published: December 2009

AbstractThe development of models for a priori assessment of the reliability of micro electromechanical systems is of crucial importance for the further development of such devices. In this contribution a partition of unity‐based cohesive zone finite element model is employed to mimic crack nucleation and propagation in a piezoelectric continuum. A multiscale framework to appropriately represent the influence of the microstructure on the response of a miniaturized component is proposed. It is illustrated that using the proposed multiscale method a representative volume element exists. Numerical simulations are performed to demonstrate the constitutive homogenization framework. Copyright © 2009 John Wiley & Sons, Ltd.
On the C1 continuous discretization of non‐linear gradient elasticity: A comparison of NEM and FEM based on Bernstein–Bézier patches
Authors: Fischer P. , Mergheim J. , Steinmann P. 
Published: December 2009

AbstractIn gradient elasticity, the appearance of strain gradients in the free energy density leads to the need of C1 continuous discretization methods. In the present work, the performances of C1 finite elements and the C1 Natural Element Method (NEM) are compared. The triangular Argyris and Hsieh–Clough–Tocher finite elements are reparametrized in terms of the Bernstein polynomials. The quadrilateral Bogner–Fox–Schmidt element is used in an isoparametric framework, for which a preprocessing algorithm is presented. Additionally, the C1‐NEM is applied to non‐linear gradient elasticity. Several numerical examples are analyzed to compare the convergence behavior of the different methods. It will be illustrated that the isoparametric elements and the NEM show a significantly better performance than the triangular elements. Copyright © 2009 John Wiley & Sons, Ltd.
Study of cure kinetics of epoxy/DDS/nanosized (SiO2/TiO2) system by dynamic differential scanning calorimetry
Authors: Safarpour M. A. , Omrani A. , Afsar S. , Zare‐Hossein‐Abadi D. 
Published: December 2009

AbstractIn this study the curing kinetics of epoxy based on the diglycidyl ether of bisphenol A (DGEBA), 4,4′‐diaminodiphenyl sulfone (DDS) as a hardener, and SiO2/TiO2 (70:30) as a nanofiller was investigated by nonisothermal differential scanning calorimetry (DSC). The effects of different weight contents of SiO2/TiO2 nanoparticles were studied using DSC in Dynamic Mode and the best value of the nanofiller was found to be 5 phr (parts per hundred). Dynamic measurements were used to obtain the total heat of reaction of the epoxy system as well as its activation energy (Ea) based on the isoconversional methods of Kissinger and Ozawa. The process revealed a dependence of the activation energy on conversion (α). The morphology of the cured system was investigated by scanning electron microscopy (SEM). It showed a strong cross‐linking between the resin and hardner and a relatively better dispersion of surface modified filler nanoparticles. Copyright © 2009 John Wiley & Sons, Ltd.
Biodegradable poly(p‐dioxanone) reinforced and toughened by organo‐modified vermiculite
Authors: Qiu Zhi‐Cheng , Zhang Jing‐Jing , Zhou Yan , Song Bo‐Ya , Chang Jing‐Jing , Yang Ke‐Ke , Wang Yu‐Zhong 
Published: December 2009

AbstractPoly(p‐dioxanone) (PPDO)/vermiculite (VMT) nanocomposites with exfoliated structure were prepared successfully by in situ intercalative polymerization of p‐dioxanone (PDO) in the presence of organo‐modified vermiculite (OVMT) with the aid of ultrasonic action. The nano‐structure of the nanocomposites was established using X‐ray diffraction (XRD) analysis and transmission electron microscopy (TEM) observations. The investigation of crystallization behavior by differential scanning calorimetry (DSC) and polarized optical microscopy (POM) proved that exfoliated OVMT platelets acted as a template for spherulite growth. The thermal stability of nanocomposites was enhanced than that of pure PPDO. Dynamic mechanical analysis (DMA) indicated nanoscale OVMT platelets restricted the motion of PPDO segments, which benefitted the increase of storage and loss modulus. The tensile properties showed that nanocomposites were reinforced and toughened significantly by the addition of nanoscale OVMT platelets. Copyright © 2009 John Wiley & Sons, Ltd.
Successful mobilization, harvest and transplant of peripheral blood stem cells using AMD3100 and G‐CSF following high dose craniospinal irradiation for medulloblastoma in a young child
Authors: Toledano Helen , Yahel Anat , Cohen Ian J. , Yaniv Isaac , Stein Jerry 
Published: December 2009

AbstractContemporary protocols for the treatment of malignant brain tumors such as medulloblastoma (MB) in children, often involve craniospinal irradiation (CSI) at diagnosis followed by serial courses of high dose chemotherapy and autologous hematopoietic stem cell support. Patients often require several pheresis procedures in order to collect sufficient stem cells for this type of treatment, particularly if they have already had CSI. We describe the successful mobilization, collection and subsequent transplant of a 7‐year‐old female with medulloblastoma after recent CSI using granulocyte colony stimulating factor (G‐CSF) and the CXCR4 antagonist AMD3100 after a failed previous mobilization attempt using G‐CSF alone. Pediatr Blood Cancer 2010;54:613–615. © 2009 Wiley‐Liss, Inc.
Poly[(N‐isopropylacrylamide)‐co‐(itaconic acid)] hydrogels with poly(ethylene glycol)
Authors: Kalagasidis Krušić Melina , Veličković Sava J , Griffiths Peter C , Filipović Jovanka 
Published: December 2009

AbstractThe aim of the work reported here was to investigate temperature‐ and pH‐sensitive hydrogels of N‐isopropylacrylamide (NIPAM) and itaconic acid (IA) and their semi‐interpenetrating polymer networks (semi‐IPNs) with varying contents of poly(ethylene glycol) (PEG). The stimuli responsiveness, swelling behaviour and mechanical properties of the hydrogels and semi‐IPNs were studied in order to investigate the effect of various amounts of PEG. Pulsed‐gradient spin‐echo NMR experiments were carried out to investigate the diffusion process. The pH sensitivity increased with an increasing amount of PEG in the semi‐IPNs, while the overall rate of water uptake was diffusion‐controlled (n < 0.5). For certain PEG contents (5 and 10 wt%), the semi‐IPNs exhibited better mechanical properties than the poly(NIPAM‐co‐IA) copolymer. The calculated values of the self‐diffusion coefficients of water indicated facilitated diffusion of water through the system with increased amounts of PEG, while the self‐diffusion coefficients of a model compound, metoprolol tartrate, showed no significant dependence on the amount of PEG. According to the results obtained and compared to results reported in the literature, the investigated semi‐IPNs may have potential applications in the controlled release of macromolecular active agents such as proteins and peptides. Copyright © 2009 Society of Chemical Industry
Biodegradable stimuli‐responsive hydrogels based on amphiphilic polyaspartamides with tertiary amine pendent groups
Authors: Moon Jong Rok , Kim Ji‐Heung 
Published: December 2009

AbstractNovel thermo‐ and pH‐responsive hydrogels based on amphiphilic polyaspartamides possessing a lower critical solution temperature (LCST) and a volume‐phase transition were prepared and characterized. The polyaspartamide derivatives were synthesized from polysuccinimide, which is the polycondensate of L‐aspartic acid monomer, through successive ring‐opening reactions using hydrophobic 2‐diisopropylaminoethylamine and hydrophilic ethanolamine. The amphiphilic copolymer was then crosslinked with hexamethylene diisocyanate to afford the corresponding gel. The LCST of the copolymer in an aqueous solution was varied by changing both the graft composition and pH of the medium. The crosslinked gels showed stimuli‐responsive behavior, with their degree of swelling and porous structure morphology changing with temperature and pH. In addition, hydrolytic degradation depending on the crosslinking density of the hydrogel was examined. Copyright © 2009 Society of Chemical Industry