bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of formulation variables on liquid‐crystal droplet size distributions in ultraviolet‐cured polymer‐dispersed liquid‐crystal cells
Authors: Henry R. M. , Sharma S. C. , Ramsey R. A. , Cramer M. L. , Atman J. B. 
Published: June 2005

AbstractThe size distributions of liquid‐crystal droplets in ultraviolet‐cured polymer‐dispersed liquid‐crystal cells have been studied with optical microscopy. It has been observed that (1) the relative masses of the liquid crystal and crosslinking agent determine the droplet size distribution for submicrometer droplet diameters and (2) only the liquid‐crystal mass fraction affects the droplet size distribution for diameters ranging from 1 to 4 μm. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1842–1848, 2005
Role of molten fraction on the structural evolution in stretching and cooling of crosslinked low‐density polyethylene: Real‐time mechano‐optical measurements
Authors: Koike Yutaka , Cakmak Miko 
Published: June 2005

AbstractWe investigated the uniaxial deformation behavior of crosslinked low‐density polyethylene in partially and substantially molten states using a real‐time true stress–strain birefringence system. The stress–birefringence behavior exhibits a multiregime behavior during stretching and holding process. The details of this regime behavior are primarily governed by the degree of unmelted crystallinity as it has a dominant role in the long‐range structural connectivity. When the long‐range physical connectivity is present, a three‐regime nonlinear stress–optical behavior was observed. When the long‐range connectivity is substantially eliminated at higher temperatures, the regime I behavior disappears. Structural studies including cooling process reveal that the lower the proportion of molten material during stretching, the higher the concentration of fibrillar structure and the shorter are the lengths of the kebabs that exhibit twisted lamellae after solidification. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1825–1841, 2005
Inhibitors of biotin biosynthesis as potential herbicides: Part 2
Authors: Ashkenazi Tali , Widberg Ayala , Nudelman Abraham , Wittenbach Vernon , Flint Dennis 
Published: June 2005

AbstractIsosteres and analogues of 7‐keto‐8‐aminopelargonic acid (KAPA) and 7,8‐diaminopelargonic acid (DAPA), the vitamer intermediates involved in the biosynthetic pathway of biotin, possessing chain lengths of eight carbon atoms, were prepared and evaluated as potential herbicides. The most active compounds, 7‐amino‐octanoic acid hydrochloride and 7‐allyloxy‐6‐oxo‐octanoic acid, displayed Arabidopsis GR50 (concentration of the active compound that causes a 50% growth inhibition) values of 5 and 10 mg kg−1 respectively. The DAPA analog 6,7‐diamino‐octanoic acid dihydrochloride, when tested in the greenhouse against six weed species, displayed moderate activity against three species, being most active against foxtail millet. Copyright © 2005 Society of Chemical Industry
Quantification of cross‐sectional morphology of porous silicon using stochastic signal spectroscopy
Authors: Parkhutik Vitali , Makusok Yuri , Inumaru Kei , Harima Yutaka 
Published: June 2005

AbstractScanning probe microscopy is presently a useful tool to study a morphology of porous semiconductors. However, it serves to visualize existing roughness features of porous samples rather then to obtain some analytical data on shape, diameter and other geometrical parameters of the pores. In this work we show the possibilities of obtaining quantitative information on the porous silicon samples through application of a so‐called Spectroscopy of Stochastic Signals (3S) to their surface profiles obtained using AFM. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Morphology and chemical composition microanalysis of 2D and 3D ordered structures on porous InP
Authors: Langa S. , Sirbu L. , Monaico E. , Carstensen J. , Föll H. , Tiginyanu I. M. 
Published: June 2005

AbstractPorous InP proves to be promising for use in nanotechnologies due to the possibility to fabricate ordered structures like two‐dimensional (2D) single crystals of nanopores. The main goal of this paper is to demonstrate that, along with 2D structures, one can fabricate 3D ordered porous structures on InP using alternative anodic current superimposed to a constant current or by pulsing the current. The dependence of the efficiency of pore diameter modulation upon the current frequency was explored. The stoichiometric composition of 2D and 3D porous InP structures was evidenced by chemical composition microanalysis. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of self‐aligned gated silicon microtip array using electrochemical silicon etching
Authors: Barillaro G. , D'Angelo F. , Pennelli G. , Pieri F. 
Published: June 2005

AbstractIn this paper we report a new approach to fabricate gated silicon microtip arrays for field emission applications using a single mask process. The key role in the fabrication process is played by the photoelectrochemical etching of silicon in HF‐based electrolytes. This technique is here exploited to produce highly uniform silicon microtip arrays. The fabrication process is detailed and the dependence of the tip geometry on the electrochemical etching parameters is discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Porous silicon‐based scaffolds for tissue engineering and other biomedical applications
Authors: Coffer Jeffery L. , Whitehead Melanie A. , Nagesha Dattatri K. , Mukherjee Priyabrata , Akkaraju Giridhar , Totolici Mihaela , Saffie Roghieh S. , Canham Leigh T. 
Published: June 2005

AbstractThis work describes the formation of porous composite materials based on a combination of bioactive mesoporous silicon and bioerodible polymers such as poly‐caprolactone (PCL). The fabrication of a range of composites prepared by both salt leaching and microemulsion techniques are discussed. Particular attention to the influence of Si content in the composite on in vitro calcification assays are assessed. For each system, cytotoxicity and cellular proliferation are explicitly evaluated through fibroblast cell culture assays. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Can chemically etched germanium or germanium nanocrystals emit visible photoluminescence?
Authors: Kartopu G. , Karavanskii V. A. , Serincan U. , Turan R. , Hummel R. E. , Ekinci Y. , Gunnæs A. , Finstad T. G. 
Published: June 2005

AbstractPhotoluminescence (PL) properties of various Ge‐based nanostructured materials, prepared using methods such as chemical etching, ion implantation and spark processing, have been studied. The PL was much stronger from the samples containing Ge nanocrystals, in comparison with their counterparts with no or less Ge nanoparticles, hinting at the likely role of the quantum confinement in Ge nanocrystals (NCs) in the light emission process. On the other hand, defects in the oxides or Ge–O bonded material alone are also shown to emit light in the same energy zone as with the Ge NCs. Discussion on these results is presented. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties and tunability of macroporous silicon 2‐D photonic bandgap structures
Authors: Haurylau M. , Shroff A. R. , Fauchet P. M. 
Published: June 2005

AbstractPhotonic bandgap (PBG) materials offer an attractive and compact way of integrating the building blocks for optical interconnects and optoelectronic circuits. In this work we demonstrate 2‐D macroporous silicon PBG structures fabricated using interferometric lithography and electrochemical etching of silicon. Optical measurements match well with simulations. We achieve tuning of the PBG using liquid crystals (LCs) infiltrated inside the porous silicon. Surface treatment methods for controlling the initial LC molecule orientation inside the pores are also demonstrated. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Impedance spectroscopy study of anodic growth of zirconium oxide film in NaOH medium
Authors: Pauporté T. , Finne J. , Lincot D. 
Published: June 2005

AbstractThe growth of anodic oxide films on zirconium metal has been followed up to 300 V by electrochemical impedance spectroscopy and scanning electron microscopy. The maximum layer thickness is 720 nm, the dielectric constant of the film is measured at 19.5 and the growth constant is 2.4 nm V–1. Above 50 V, the presence of two impedance relaxations between 1 Hz and 200 kHz reveals a bilayered structure. This may be a consequence of a lower resistivity of the outer layer induced by some electrolytic solution infiltration into film defects. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cathodoluminescent properties of tin dioxide sol–gel doped with Tb3+ and Eu3+ grown in porous silicon
Authors: Moadhen A. , Elhouichet H. , Jardin C. , Oueslati M. , Roger J. A. 
Published: June 2005

Abstract Tin dioxide doped with antimony (SnO2:Sb) and sol–gel doped with terbium (Tb3+) were deposited on porous silicon (PS) layers and on monocrystalline Si wafers. Energy dispersive X‐ray (EDX) analysis and Auger electron spectroscopy (AES) show the presence of tin, oxygen and terbium in the PS matrix. Preliminary measurements on cathodoluminescent emission are presented. The mechanism of rare‐earth emission is discussed through a comparative study of the cathodoluminescence (CL) of SnO2:Sb:Tb3+/PS and SnO2:Sb:Tb3+/Si. A strongly enhanced CL efficiency of SnO2:Sb sol–gel doped with Tb3+ and Eu3+ ions deposited in PS is reported. The enhancement is attributed to a process of excitation transfer between rare‐earth ions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The effect of etching with glycerol, and the interferometric measurements on the interface roughness of porous silicon
Authors: Kan P. Y. Y. , Foss S. E. , Finstad T. G. 
Published: June 2005

AbstractWe have carried out interferometric measurements of interface roughness in‐situ during electrochemical etching of p‐type porous silicon (PS) at room temperature. We found that at a certain porosity (∼70%) and with an electrolyte where a low fraction (10%) of the ethanol was replaced with glycerol, there was a significant decrease of the interface roughness. However, a higher content of glycerol (>10%) increased the surface roughness. We have varied the current density in the electrolytic cell and the HF concentration of the electrolyte. We also found that the porosity of the PS varied only slightly when glycerol at various concentrations was used. This investigation shows that an interferometric technique could be a useful tool for measuring the etch rate and the interface roughness of the PS. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Infrared analysis of porous silicon carbide
Authors: Rossi A. M. , Giorgis F. , Ballarini V. , Borini S. 
Published: June 2005

AbstractWe report on the optical spectroscopies performed on porous SiC obtained by electrochemical etching of 6H–SiC wafers. Strong modifications of Raman and infrared spectra, characteristic of the porous material, have been detected. Various effective medium approximations have been employed for the modeling of porous SiC dielectric function, in order to interpret the infrared reflectance features. Comparison between computational and experimental results indicates the Maxwell–Garnett model as the most appropriate approximation, and suggests that charge carriers within the porous matrix are likely to play a role in the interaction of the material with electromagnetic radiation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the mechanism of photodegradation of porous silicon in oxygen‐containing ambient
Authors: Saren A. A. , Kuznetsov S. N. , Pikulev V. B. , Gardin Yu. E. , Gurtov V. A. 
Published: June 2005

AbstractAn explanation of the mechanism of porous silicon (PS) photodegradation in an oxygen‐containing ambient has been proposed. The specific oxidation of luminescent Si nanocrystallites in a porous layer occurs via an intermediate specie, namely ozone produced in oxygen under illumination over a wide range of photon energies. It is shown by photoluminescence (PL), electron spin resonance (ESR) and capacitance–voltage methods that ozone‐induced oxidation is accompanied by defect generation at the Si crystallite/oxide interface. Some of these centers act as a nonradiative drain for electron–hole pairs under PL excitation. As revealed by capacitance spectroscopy in an MOS structure with a porous sublayer, these defects constitute an interface states spectrum broadly spread through the silicon band gap. The above‐mentioned defects appear in ESR spectra as Pb‐like centers originated from incomplete passivation of silicon bonds with oxygen at the crystallite surface. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
FTIR investigation of porous silicon formed in deutrofluoric acid based solutions
Authors: Belogorokhov A. I. , Gavrilov S. A. , Kashkarov P. K. , Belogorokhov I. A. 
Published: June 2005

AbstractAbsorption of infrared radiation in the porous silicon (PS) films prepared by common electrochemical etching in DF‐ethanol‐D6 solutions was studied. We report our results of the effect of deuterium termination on the process of surface states changes of the PS after their exposure to ambient air for few months. In addition to these results, we also show that the replacement of hydrogen with deuterium leads to decreasing the concentration of the silicon dangling bonds at the surface of the PS. As a result, more stable passivation layer was formed. There were not any detectable quantities of the hydrogen atoms at the surface of PS during few months after its preparation. This fact is explained from the point of view of the dissociative water adsorption mechanism. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of oscillatory behavior of open‐circuit potential of silicon immersed in CuSO4/HF solutions
Authors: Parkhutik V. , Rayon E. , Pastor E. , Matveeva E. , Sasano J. , Ogata Y. 
Published: June 2005

AbstractThis work studies the influence of experimental conditions on the occurrence and development of oscillations of the open‐circuit potential (OCP) of silicon immersed in aqueous solution of 0.01 M CuSO4 + 0.06 M HF. The oscillations are very regular and last for days without any tendency to diminish. We show that they are quite sensitive to the temperature of the electrolyte, its viscosity, stirring, relative concentration of components, etc. We also present a phenomenological model to explain the oscillatory OCP behavior. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of drug load in porous silicon microparticles by calorimetry
Authors: Salonen J. , Paski J. , Vähä‐Heikkilä K. , Heikkilä T. , Björkqvist M. , Lehto V.‐P. 
Published: June 2005

AbstractDifferent kind of drugs can be loaded into the porous silicon microparticles for oral dosing. In cases where the drug is in its crystalline form in the pores, the amount of the loaded drug can be determined accurately using a calorimetric method, thermoporometry. Even if the drug substance is not in crystalline form a sophisticated estimation can be given. In this work ibuprofen, antipyrine, and ranitidine have been studied. Ibuprofen and antipyrine were easily detected and quantified, but ranitidine, which does not penetrate into the PSi microparticles in its crystalline form, could only be qualitatively determined. The possibility to quantify this kind of drug substance is also discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Submicrometer period silicon diffraction gratings by porous etching
Authors: Nagy N. , Volk J. , Hámori A. , Bársony I. 
Published: June 2005

AbstractWe have developed a new technique to manufacture diffraction gratings on porous silicon and on silicon interface. Using holography facilitate to adjust the periodic length of gratings in the submicron range. The holographically exposured and developed photoresist applied on the silicon surface provides the mask for the ion implantation. The sinusoidal grating between the substrate and the porous silicon layer is achieved after the anodic etch process. The PS layer can be removed by alkali etching. Sinusoidal one‐ and two‐dimensional diffraction gratings have been produced with 375 nm periodic length. Their AFM images are shown. The diffraction efficiencies were measured. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Formation technique for macroporous morphology superlattice
Authors: Zheng J. , Christophersen M. , Bergstrom P. L. 
Published: June 2005

AbstractIn this work, the investigators studied etching conditions for generating macro porous silicon with different morphologies in p‐type (111) substrates. Both crystal orientation dependent growth of macropores and electric current direction dependent growth of macropores have been achieved. A superlattice structure, which consists of several layers of macroporous silicon with different morphologies, has been demonstrated by modulating the etch conditions during the anodization process. The morphology superlattice structure is developed for an inlet particle filter of a micro gas chromatograph (µGC). It may offer a number of other new MEMS applications. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modification of cubic susceptibility tensor in birefringent porous silicon
Authors: Zabotnov Stanislav V. , Konorov Stanislav O. , Golovan Leonid A. , Fedotov Andrei B. , Timoshenko Victor Yu. , Zheltikov Aleksei M. , Kashkarov Pavel K. 
Published: June 2005

AbstractPolarization‐sensitive third‐harmonic generation in birefringent (110) porous silicon layers reveals a modification in the cubic susceptibility tensor of silicon caused by strongly anisotropic pores. The ratio $ (\chi _{1111} ^{(3)} + \chi _{1122} ^{(3)} / \chi _{3333} ^{(3)}) $ of cubic susceptibility tensor components for the porous layers is shown to be 40% higher than this ratio for crystalline silicon. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Use of porous GaAs electrodes in photoelectrochemical cells
Authors: Cojocaru A. , Simashkevich A. , Sherban D. , Tiginyanu I. , Ursaki V. , Tsiulyanu I. , Usatyi I. 
Published: June 2005

AbstractThe photoelectrochemical properties of semiconductor‐electrolyte solar cells with carbon auxiliary electrode and colloidal aqueous solution of Na2SiO3 have been investigated. Bulk n‐type single crystalline and nanoporous GaAs material were used as semiconductor electrodes. Current–voltage characteristics under different illumination intensities and spectral distribution of the photosensitivity were studied. The photopotential was found to reach values as high as 0.46 V for bulk n‐GaAs. The introduction of porosity in GaAs shifts the maximum of the spectral distribution of photosensitivity towards the longwavelength region and increases the short circuit current by a factor of two. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pore filling of macropores prepared in p‐type silicon by copper deposition
Authors: Harraz F. A. , Kamada K. , Sasano J. , Izuo S. , Sakka T. , Ogata Y. H. 
Published: June 2005

AbstractCopper deposition into ordered macroporous silicon prepared in p‐type substrates was investigated by immersion plating and electrochemical deposition in an aqueous solution containing Cu2+ ions. When the sample was immersed in 0.1 M CuSO4 solution at the open circuit potential, Cu crystallites are clearly observed at the top surface and inside the pores. The deposition of Cu oxidizes the substrate simultaneously to SiO2. On the other hand, the potentiostatic deposition in the dark revealed that Cu deposits preferentially at the pore bottom and propagates towards the top surface. Furthermore, when the substrate was illuminated under cathodic potential, the Cu deposition was enhanced mainly at the top‐surface and around the pore walls. The different deposition behavior was compared and discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carbonic anhydrase adsorption in porous silicon studied with infrared ellipsometry
Authors: Arwin H. , Karlsson L. M. , Kozarcanin A. , Thompson D. W. , Tiwald T. , Woollam J. A. 
Published: June 2005

AbstractThe refractive index N = n + ik of the protein bovine carbonic anhydrase (BCA) adsorbed in porous silicon layers is determined using infrared spectroscopic ellipsometry. Five absorption bands in the amide region are resolved. The distribution of the protein inside the porous matrix is modelled and it is found that more BCA per internal surface area are adsorbed in the upper part of the porous layer than in the bottom part. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Porous silicon – rare earth doped xerogel and glass composites
Authors: Balakrishnan S. , Gun'ko Yurii K. , Perova T. S. , Rafferty A. , Astrova E. V. , Moore R. A. 
Published: June 2005

AbstractThe development of components for photonics applications is growing exponentially. The sol–gel method is now recognised as a convenient and flexible way to deposit oxide or glass films on a variety of hosts, including porous silicon. In the present work we incorporated erbium and europium doped xerogel into porous silicon and developed new porous silicon – rare earth doped glass composites. Various characteris‐ation techniques including FTIR, Raman Spectroscopy, Thermal Gravimetric Analysis and Scanning Electron Microscopy were employed in this work. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic nanoparticles – porous silicon composite material
Authors: Balakrishnan S. , Gun'ko Yurii K. , Perova T. S. , Venkatesan M. , Astrova E. V. , Moore R. A. 
Published: June 2005

AbstractNew composite magnetite – porous silicon materials have been prepared. The materials have been studied using various characterisation techniques such as Raman, XRD, magnetic measurements and SEM. Self‐organisation of magnetic particles into linear micro‐assemblies on the porous silicon surface has been observed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Laterally stacked porous silicon multilayers for subquart micron period UV gratings
Authors: Volk J. , Norbert N. , Bársony I. 
Published: June 2005

AbstractA novel method was presented to prepare porous silicon Bragg grating structures. With this technique the grating period can be easily tuned in a wide range. In the porous silicon multilayer formation there is no theoretical limit for the period to be lowered to even below 100 nm. Both phase and mixed type (amplitude and phase) optical grating are demonstrated. Another unique feature of these structures is, that contrary to the case of commonly used porous silicon layers, here the pores are lying parallel to the wafer surface. This might be a valuable asset e.g. in microfluidic‐type sensor development. The paper discusses design and processing constraints. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Third harmonic generation in a periodic structure with simultaneous linear and nonlinear modulation
Authors: Huang Cheng‐ping , Zhu Yong‐yuan 
Published: June 2005

AbstractA new scheme for third harmonic generation is proposed, where periodic structures with simultaneous linear and nonlinear modulation are employed. In the quasi‐phase‐matching conditions, the coupling equations are presented and analyzed, and efficient third harmonic generation can be achieved. The results suggest the availability of periodic structures in realizing multiple frequency conversion processes. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)