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111.
Hideo Sawada Hiroshi Kakehi Masashi Koizumi Yoshihiro Katoh Masashi Miura 《Journal of Materials Science》2007,42(17):7147-7153
Fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomer [RF-(DOBAA)
n
-RF] reacted with tetraethoxysilane (TEOS) and silica nanoparticles in the presence of low-molecular weight biocides such as
hibitane, hinokitiol, and hinokioil under alkaline conditions to afford RF-(DOBAA)
n
-RF/silica nanocomposites-encapsulated these biocides in excellent to moderate isolated yields. Fluoroalkyl end-capped N,N-dimethylacrylamide oligomer [RF-(DMAA)
n
-RF] and acrylic acid oligomer [RF-(ACA)
n
-RF]/silica nanocomposites-encapsulated hibitane were obtained under similar conditions. Dynamic light scattering measurements
showed that the size of these fluorinated nanocomposites-encapsulated biocides thus obtained is nanometer size-controlled.
Additionally, these fluorinated nanocomposites were shown to have a good dispersibility and stability in methanol and water.
Of particular interest, these fluorinated nanocomposites-encapsulated biocides were found to have a good antibacterial activity
against Staphylococcus aureus, and these nanocomposites were applied to the surface modification of traditional organic polymers such as poly(methyl methacrylate). 相似文献
112.
113.
Saeed Kazemi Najafi Alireza Abbasi Marasht Ghanbar Ebrahimi 《Journal of Materials Science》2007,42(3):789-793
Ultrasonic wave velocities were determined at parallel and perpendicular to manufacturing direction and at the interval angles
of 15° in clockwise and counterclockwise directions of particleboard and fiberboard. The experimental results were compared
with the predicted values using some empirical formulae such as Hankinson and Jacoby equations. The results showed that the
ultrasonic wave velocity were the highest in parallel direction in particleboard and fiberboard and decreases with increase
of angle and the lowest values occurred in perpendicular direction. The predicted ultrasonic velocity using Hankinson and
Jacoby equations are in close agreement with the measured values. Relationship between ultrasonic wave velocities and particles
and fibers angle could be successfully presented by cubic and quadratic regression equations as well. 相似文献
114.
115.
116.
Mamiko Hori Cécile Pagnoux Jean-François Baumard Masayuki Nogami 《Journal of Materials Science》2007,42(1):80-86
A new method is proposed to produce gold nanoparticles (GNP) by in situ reduction of a gold salt dissolved in water. The reducing
agent used is Tiron instead of the citrate anion most often mentioned in literature. The influence of various parameters has
been investigated, such as the content of Tiron with respect to that of the precursor of gold HAuCl4, or the initial pH of the solution after mixing of reactants. It is shown that Tiron also exerts a positive influence as
a dispersant, which impedes agglomeration of gold nanoparticles. The typical average size of GNP synthesized in the present
work is close to 7 nm. 相似文献
117.
118.
A silver palladium (Ag/Pd) alloy powder is used as an example material to illustrate potential applications of electrophoretic deposition (EPD) in electronics manufacturing, in particular the forming of multilayer devices. The dispersion and deposition of the Ag/Pd powder in acetic acid is characterized. It is found that deposition can be explained by the direct action of electrostatic force on individual particles. Depositions of this Ag/Pd powder are then used to demonstrate: forming of a continuous layer on a rigid substrate; forming of continuous layers in laminated and sintered BaTiO3 multilayers; and incorporation of patterned depositions into a multilayer by either overcasting the patterned deposition with a particulate slip to form a multicomponent tape, or direct lamination of the patterned deposition to a low temperature co-fired ceramic (LTCC) tape. It is shown that electrically conducting layers can be formed at an average thickness of only two times the diameter of the starting powder. Continuous conductor lines thirty times the average diameter of the starting powder were formed. 相似文献
119.
Wouter Bergmann Tiest Marcel Bruijn Henk Hoevers Piet de Korte Jan van der Kuur Wim Mels 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2004,520(1-3):329-332
We have performed numerical calculations of the noise in voltage-biased superconducting transition edge-based X-ray microcalorimeters, using a finite-element model. Details of the model are discussed, as well as results for different absorber geometries. The results are in agreement with an analytical model and show that the amount of internal thermal fluctuation noise can be reduced by using a segmented absorber. The simulation also agrees well with experimental data, which, for our detectors, contain no major unidentified noise sources. Furthermore, the discrepancy between the (small-signal) theoretical and the measured energy resolutions for 5.9 keV X-rays, for our sensors typically a factor of 2, is explained by a more accurate modelling of the sensor responsivity, taking into account the large signal behaviour. 相似文献
120.
D.J. Bekers S.J.L. van Eijndhoven A.A.F. van de Ven 《Journal of Engineering Mathematics》2004,49(4):373-390
A long thin conducting stripline embedded in a dielectric and centered between two large conducting plates, i.e., the stripline environment, is considered. The stripline is modeled as infinitely long, infinitely thin, and perfectly conducting by first considering a stripline of finite length, thickness, and conductivity in a dielectric layer. Starting from Maxwell's equations and assuming that the current on the stripline is a propagating wave in length direction, asymptotic expressions for the fields inside and in the neighbourhood of the stripline are deduced. These expressions are used to model the stripline in the stripline environment, which leads to a boundary-value problem for the electric potential. This problem is solved by two different approaches, leading to integral equations for the current and for an auxiliary function describing the electric potential. A relation between the current and the auxiliary function is deduced, which is used to obtain asymptotic expressions for current and impedance. Results are compared with a numerical solution of the integral equation for the current and with results in literature. 相似文献