bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermophysical Properties and Molecular Relaxations in Cured Epoxy Resin + PEO Blends: Observations on Factors Controlling Miscibility
Authors: Kalogeras Ioannis M. , Vassilikou‐Dova Aglaia , Christakis Iraklis , Pietkiewicz Dorota , Brostow Witold 
Published: April 2006

AbstractSummary: Thermophysical properties and molecular relaxations in aromatic amine‐cured diglycidyl ether of bisphenol‐A (DGEBA) epoxy oligomer and poly(ethylene oxide) (PEO) mixtures were determined by DSC and dielectric techniques (TSC, DRS). The binary blends were judged to be fully miscible in the amorphous state (wPEO < 40 wt.‐%), as evidenced by the single composition‐dependent glass transition temperatures Tgs. In the amorphous blends, negative deviations of dielectric/thermal Tg‐estimates from the linear mixing rule or the behavior predicted by the Fox equation reveal weaker intermolecular interactions, compared to strong self‐association of hydroxyls in the cured thermoset. Morphological changes in PEO‐rich blends (wPEO ≥ 40 wt.‐%) are in accordance with their complicated interface structure, previously reported to consist of amorphous PEO regions, branched epoxy resin chains and an imperfect epoxy resin network located between PEO lamellae. In these blends, PEO crystallites exert steric hindrances in the amorphous regions, causing strong Tg upshifts. Changes in the relaxation dynamics of glyceryl segments (e.g., in the activation energy barrier and relaxation strength) are in accordance with the idea that the close matching between the molecular polarities of PEO, epoxy resin and the cure agent significantly contributes to the observed miscibility.Plots of transition temperatures as function of blend composition.magnified imagePlots of transition temperatures as function of blend composition.
From the Micro‐ to the Macro‐: Managing the Conservation of the Warship, Vasa
Authors: Hocker Emma 
Published: April 2006

AbstractSweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large‐scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re‐treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum.
The Effects of UV Laser Radiation as Sterilizer for Cultural Heritage
Authors: Belloni Fabio , Nassisi Vincenzo , Alifano Pietro , Monaco Caterina , Panzanaro Santina 
Published: April 2006

AbstractThis work reports on a novel sterilization technique for bacteria which may be involved in deterioration of cellulose‐based antiquities (paper, textile and wood). The bacterium we processed, a Nonomuraea sp. strain, was a mycelial microorganism belonging to the Actinomycetes group. This group includes many microorganisms that are able to attack cellulose and/or lignin. Escherichia coli was used as a reference microorganism. The UV source used as sterilizer was an excimer laser operating at 308 nm, 1 Hz. We demonstrated that, under different experimental conditions, the sterilization process was effective just after few seconds. For laser irradiation at 80 mJ/cm2 per pulse, survival rate decreased of three orders of magnitude just after 75 s. The measurement of the absorption cross section for 308 nm photons on Nonomuraea sp. cells was also carried out.
Biodeterioration of Paper: A SEM Study of Fungal Spoilage Reproduced Under Controlled Conditions
Authors: Pinzari Flavia , Pasquariello Giovanna , De Mico Antonella 
Published: April 2006

AbstractBiodeterioration phenomena represent a complex of physical and chemical alteration processes in various materials, such as those constituting the objects that represent our cultural heritage. The biodegradation of paper is conditioned by several variables such as the materials from which cellulose is obtained, the manufacturing processes employed, the occurrence of other affecting substances such as lignin or metallic compounds, and by the environmental conditions in which papers are conserved. In this study, biodeterioration of paper was artificially induced in order to evaluate the role of a range of chemical and physical variables on damage caused by cellulolytic fungi. A variable pressure SEM instrument was used to characterise paper samples with different fibre origins, and alterations obtained in vitro. Two fungal strains, Aspergillus terreus Thom and Chaetomium globosum Kunze, which are cellulolytic species frequently associated with paper spoilage, were used to produce stains with characteristics close to those observable on art objects made from paper. The stains obtained on the different samples of paper were compared at both low and high magnification, in order to visualize the macro‐ and microscopic characteristics of paper fibres, inorganic constituents, impurities, and the deteriorating agents related to the spoiled areas. During this survey it was observed that single paper characteristics can strongly influence the intensity and the results of the fungal action. For example, the activity of a fungal strain on paper grades containing fibres of the same origin, but with different sizing, led to the formation of profoundly different stains and alterations. Moreover fungal structures, analysed by low vacuum SEM, in areas on paper corresponding to the stains appeared in different physiological states suggesting an important effect of paper constituents on fungal growth and their sporulating ability.
Durability of Protective Polymers: The Effect of UV and Thermal Ageing
Authors: Poli T. , Toniolo L. , Sansonetti A. 
Published: April 2006

AbstractThis paper aimed at studying thermal contribution to the UV ageing process, trying to understand which decisive changes reduce the protective effectiveness of polymer coatings. In this paper the effects on the shielding efficacy of different protective polymers, applied on different low porosity stones have been studied, comparing ageing of a 1000 h simulated solar UV radiation with thermal ageing at about 50 °C, which is the temperature usually reached in UV chambers. The aim of the study has been the evaluation of a possible thermal contribution: the testing methods have been suggested by UNI‐Normal Italian protocol and include capillary water absorption, static contact angles and colour variation measurements. A reduction in protective efficacy has been highlighted, probably due to both oxidation and a surface rearrangement of the polymeric material; in most cases chemical degradation of the macromolecules did not occur.
Efficient DNA Extraction and Amplification of Samples from the Archeological Site of Pompei (Italy)
Authors: Ranalli Giancarlo , Belli Claudia , Lustrato Giuseppe , Meloscia Antonia , Orsini Massimiliano 
Published: April 2006

AbstractDue to their growth and metabolism, microorganisms can cause severe damage to Cultural Heritage, through mechanical and chemical processes. In this paper we used molecular approaches to study bacterial communities on samples from the archeological site of Pompei (Italy). In particular four DNA extraction methods without prior cultivation of the microflora were compared. In terms of efficiency, the DNA extraction method based on the Tri‐Reagent™ kit gave the best results. All extraction protocols coupled with 16S rDNA fragments PCR amplification were satisfactory; but the best results were obtained by Klentaq DNA LA Polymerase™; this enzyme can be considered an effective tool for amplification of DNA from Cultural Heritage and possibly other environmental samples.
The 8π‐problem for radially symmetric solutions of a chemotaxis model in the plane
Authors: Biler Piotr , Karch Grzegorz , Laurençot Philippe , Nadzieja Tadeusz 
Published: April 2006

AbstractThe existence, uniqueness and large time behaviour of radially symmetric solutions to a chemotaxis system in the plane ℝ2 are studied either for the critical value of the mass equal to 8π or in the subcritical case. Copyright © 2006 John Wiley & Sons, Ltd.
Regularity in Sobolev spaces of steady flows of fluids with shear‐dependent viscosity
Authors: Ebmeyer Carsten 
Published: April 2006

AbstractThe system

is considered on a bounded three‐dimensional domain under no‐stick boundary value conditions, where S has p‐structure for some p<2 and D(u) is the symmetrized gradient of u. Various regularity results for the velocity u and the pressure π in fractional order Sobolev and Nikolskii spaces are obtained. Copyright © 2006 John Wiley & Sons, Ltd.
Dispersion and attenuation characteristics of asymmetric multiconductor lines in suspended substrate structure using full‐wave modal analysis
Authors: Srivastava Kumar Vaibhav , Awasthi Seema , Biswas Animesh 
Published: April 2006

AbstractThe dispersion characteristics of asymmetric multiconductor lines in shielded suspended substrate (SSS) are evaluated using hybrid‐mode formulation. The numerical procedure, based on full‐wave modal analysis, is formulated to compute all the frequency‐dependent normal‐mode parameters for asymmetric multiconductor lines in a suspended substrate structure. The numerical results include the propagation constants, modal characteristic impedances, and attenuation constant. The perturbation formula has been used for the calculation of conductor and dielectric losses in the suspended substrate structure. Conductor loss is computed for the finite thickness using the perturbation theory and a comparison plot is provided to validate results. Dispersion characteristic of asymmetric three and four coupled microstrip lines in SSS are presented first time in this paper. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1305–1310, 2006; Published online in Wiley Inter‐Science (www.interscience.wiley.com). DOI 10.1002/mop.21615
Shaped‐reflector antenna designs using particle swarm optimization: An example of a direct‐broadcast satellite antenna
Authors: Xu Shenheng , Rahmat‐Samii Yahya , Gies Dennis 
Published: April 2006

AbstractA novel shaped‐reflector antenna synthesis technique based on the particle swarm optimization (PSO) algorithm is presented. The reflector surface is expanded using the modified Jacobi polynomials, and the expansion coefficients and other antenna parameters compose a solution space to be explored by PSO in a global stochastic evolutionary manner. The conventional weighted aggregation (CWA) method is utilized when multiple objectives are considered. The validity of this technique is verified by an example application, a shaped‐reflector antenna for simultaneous reception from multiple satellites for direct‐broadcast satellite (DBS) services. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1341–1347, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21618
Backward‐wave directional coupler with complete coupling and broadband using conventional microstrip and 1D mushroom structure
Authors: Lee Jae‐Gon , Lee Jeong‐Hae 
Published: April 2006

AbstractA new type of backward‐wave coupled‐line directional coupler with complete coupling and broadband, which is composed of a conventional microstrip and a 1D mushroom structure, is proposed. The 1D mushroom structure is employed for a double negative (DNG) transmission line. The coupler exhibits unusual characteristics such as complex propagation. The complex propagation constant of the coupled mode enables strong coupling due to exponential field decay. The performance of the proposed coupler is verified by c‐ and π‐mode analysis, full‐wave simulation, and measurement. The measured coupling level of −0.5 dB with 3‐dB fractional bandwidth of 35% and high directivity of 30 dB is achieved. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1293–1296, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21622
Simple models for predicting transmission properties of photonic crystal fibers
Authors: Albandakji Rachad , Safaai‐Jazi Ahmad , Stolen Roger 
Published: April 2006

AbstractSimple, fast, and efficient 1D models for evaluating the transmission properties of photonic crystal fibers are proposed. Using these models, axial propagation constant, chromatic dispersion, effective area, and leakage loss can be predicted with a reasonable accuracy but much faster than often time‐consuming 2D analytical and numerical techniques and with much less computational resources. It is shown that the results are in good agreement with the published data available in the literature. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1286–1290, 2006; Published online in Wiley InterScience (www. interscience.wiley.com). DOI 10.1002/mop.21624
Planar compact, broad‐stopband elliptic‐function lowpass filters using high‐permittivity ceramic substrate
Authors: Chen Yuan‐Bin , Huang Cheng‐Liang , Lin Shih‐Hung 
Published: April 2006

AbstractThe miniaturization of hairpin lowpass filters by employing two high‐permittivity ceramic substrates (with respective dielectric constants of 9.7 and 22.6) are investigated. Microwave dielectric ceramics with high permittivity are commonly applied in several microwave communication components. With the advantages of compact size, high‐permittivity ceramics can be used as the substrate for low‐pass filters. Moreover, the fundamental characteristics of newly developed compact stepped‐impedance hairpin resonators with parallel coupled lines have also been described and applied to the design of lowpass filters. In this paper, the designed multiple cascaded stepped‐impedance hairpin resonators structures are simulated using an IE3D simulator. The responses of the fabricated filters using Al2O3 (εr = 9.7, Q × f = 350,000 GHz) and 0.2 Ca0.6La0.26TiO3–0.8Mg0.95Co0.05TiO3 (εr = 22.6, Q × f = 57,000 GHz) ceramic substrates are designed at a cutoff frequency of 1.8 GHz. This compact, low‐loss, sharp cutoff‐frequency response, and broad‐stopband lowpass filter should be useful in many wireless communication systems. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1432–1436, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21635
A modified dual‐band microstrip monopole antenna
Authors: Lu Lu , Coetzee Jacob Carl 
Published: April 2006

AbstractA modified microstrip‐fed planar monopole antenna with an open‐circuited coupled line is presented in this paper. The operational bandwidth of the proposed antenna covers the 2.4‐GHz ISM band (2.42–2.48 GHz) and the 5‐GHz WLAN band (5–6 GHz). The radiating elements occupy a small area of 23 × 8 mm2. The finite‐difference time‐domain (FDTD) method is used to predict the input impedance of the antenna. The calculated return loss shows very good agreement with the measured data. Reasonable antenna gain is observed across the operating band. The measured radiation patterns are similar to those of a simple monopole antenna. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1401–1403, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21636
Tunable fiber laser based fiber Bragg grating strain sensor demodulation system with enhanced resolution by digital signal processing
Authors: Yun Binfeng , Wang Yiping , Li Anmin , Cui Yiping 
Published: April 2006

AbstractA fiber Bragg grating strain sensor demodulation system based on the wavelength‐tunable fiber‐ring laser (WTFRL) is developed. The finite impulse response (FIR) digital filter and the centriod detection algorithm (CDA) are implemented to reduce the system noises and to improve the resolution of the Bragg wavelength‐shifts detection. The experiments show that with this signal processing technique, the resolution of the fiber Bragg grating (FBG) strain sensor is 1.39 με, which is much better than the resolution (10.1 με) of the direct peak‐detection method. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1391–1393, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21638
Scalable distributed‐capacitance model for silicon on‐chip spiral inductors
Authors: Huang Fengyi , Lu Jingxue , Jiang Nan 
Published: April 2006

AbstractWe present physics‐based modeling for silicon on‐chip spiral inductors, taking into account the coupling capacitance between metal spirals. The coupling capacitance Cp is calculated using a distributed‐capacitance model based on finite‐element analysis. As demonstrated for a series of inductors with the number of turns ranging from 2.5 to 6.5 fabricated in a 0.18‐μm CMOS technology, the current model provides simulation results for the quality factor Q, the S‐parameter, and the self‐resonance frequency fSR that are in good agreement with the measurements without any fitting parameters. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1423–1427, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21642
Genetic algorithm demodulation technique for fibre Bragg gratings resonant cavity
Authors: André P. S. , Pellegrino Lara P. , Teixeira A. L. , Nogueira R. N. , Lima M. M. , Monteiro P. 
Published: April 2006

AbstractWe present a demodulation technique to synthesise the physical parameters of an optical fibre Bragg grating (FBG) resonant cavity. The demodulation is achieved through a genetic algorithm (GA). The estimated parameters allow us to simulate the cavity amplitude response, arriving at an accurate response when compared to the experimental results. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1415–1417, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21644
Novel distortion resilient OSNR monitoring technique based on evaluation of asynchronous histograms
Authors: Luís R. , Teixeira A. , André P. , Monteiro P. 
Published: April 2006

AbstractThis paper presents a novel technique to evaluate OSNR using asynchronous histograms. The technique is based on a comparison between a numerically estimated asynchronous histogram of the signal to be measured and the monitored signal. Experimental validation of proposed technique is presented. Measurement errors below 1 dB are achieved for OSNR values below 32 dB. The proposed technique is also validated for cases where the monitored signal presents significant dispersion‐induced distortion, without presenting significant loss of accuracy. The principal limitations of the proposed technique are also investigated. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1369–1372, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21648
A subsystem embedded microstrip antenna structure for satellite radio applications
Authors: Chou Hsi‐Tseng , Hsu Chieh‐Sheng 
Published: April 2006

AbstractA microstrip antenna structure with RF components embedded inside the structure is proposed for satellite radio applications. The space to embed the RF components is created by a metal cavity inside the substrate of the antenna structure. With the increasing use of MMIC techniques, the thickness of the substrate will be sufficient to accommodate the RF components. Hence, the structure has the advantages of a compact subsystem and a small overall system thickness, which may increase a variety of applicable areas. Numerical studies and experimental examinations are performed to validate the performance of the antenna. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1350–1354, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21650
Compact diplexer and its implementation for wireless communication systems
Authors: Lee Byoung Hwa 
Published: April 2006

AbstractA new compact and effective lumped‐element diplexer structure targeted for low‐temperature co‐fired ceramic (LTCC) implementation is proposed that can exhibit high levels of isolation between the low‐pass and high‐pass filters. Design equation formulations that take into account the isolation between two filters are presented. As an example, a diplexer for a dual‐mode portable telephone for 900‐MHz digital cellular and 1.9‐GHz personal communication systems is designed and fabricated. According to the measured results, insertion losses within the passbands of low‐pass and high‐pass filters are both less than 0.5 dB. Minimum 20‐dB rejection of low‐pass filter at the passband of high‐pass filter is achieved, and vice versa. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1413–1415, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21652
Tapered CPW‐fed printed monopole antenna
Authors: Liang Xian‐Ling , Zhong Shun‐Shi , Wang Wei 
Published: April 2006

AbstractA compact coplanar rectangular monopole antenna fed by a tapered coplanar waveguide (CPW) feeder in the middle of a trapeziform ground plane is introduced. By using the tapered CPW feeder, the impedance bandwidth of the antenna is enhanced by a factor of about 1.7 compared with a 50Ω CPW feeder. The measured ratio impedance bandwidth reaches about 10.7:1, covering frequencies from 0.76 to 8.15 GHz. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1411–1413, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21653
A design of a microstrip electromagnetic dual‐band bandgap (DB‐EBG) structure
Authors: Çakir Gonca , Sevgi Levent 
Published: April 2006

AbstractThe design, simulation, and experimentation steps of a novel low‐cost, small‐size microstrip electromagnetic dual‐band bandgap (DB‐EBG) structure is presented. The numerical simulations are performed via an in‐house‐prepared 3D finite‐difference time‐domain (FDTD) package and the experiments are carried out using an Agilent‐8714 ES network analyzer. The simulations and measurements confirm that the dual‐stopband characteristics can be controlled via the stub parameters. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1405–1408, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21655
Wideband EMC chip antenna for WLAN/WiMAX operation in the sliding mobile phone
Authors: Lin Chun‐I , Wong Kin‐Lu , Yeh Shih‐Huang 
Published: April 2006

AbstractA wideband electromagnetic‐compatible (EMC) chip antenna for application in the sliding mobile phone for WLAN/WiMAX dual‐network operation is presented. The proposed EMC antenna is easily fabricated by mounting a metal pattern onto a foam base of 30 × 6 × 6 mm3. The metal pattern comprises a radiating portion and a vertical ground plane. The radiating portion further consists of a shorted driven strip and a shorted parasitic strip, both of them together generating a wide bandwidth for 2.4‐GHz WLAN operation (2400–2484 MHz) and 2.5‐GHz WiMAX operation (2500–2690 MHz). The vertical ground plane functions as an effective shielding wall and allows the antenna to be in direct contact with nearby electronic components or conducting elements. Small variations on the performances of the proposed antenna for the sliding mobile phone in the slid‐open (talk) and standby conditions are also obtained. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1362–1366, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21657