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121.
Effect of essential oil compounds and plant extracts on decay and termite resistance of wood 总被引:2,自引:0,他引:2
S. Nami Kartal Won-Joung Hwang Yuji Imamura Yasuo Sekine 《Holz als Roh- und Werkstoff》2006,64(6):455-461
Essential oils and their derivatives have a long history of safe usage as antimicrobial agents in food industry. In this study various essential oils and extracts from plants were screened for their ability to inhibit wood decay and termite attack in laboratory decay and termite resistance tests using treated wood specimens. In the laboratory decay resistance tests, wood specimens treated with essential oil compounds were subjected to brown-rot fungus, Tyromyces palustris, and white-rot fungus, Trametes versicolor for three months. The specimens were also subjected to termite attack by subterranean termites, Coptotermes formosanus for three weeks in laboratory conditions. The formulation with cinnamaldehyde (DF3) was found to be effective against both the brown-rot and white-rot fungi used in the study. However, the formulation with cinnamic acid (DF8) was able to protect wood specimens against only the white rot fungus and about 50% mass loss occurred in the specimens subjected to the brown-rot fungus. The mass losses in the wood specimens treated with cassia oil containing formulation (DF4) showed that cassia oil was effective against both fungi. The wood tar oil and dodecanal compounds also inhibited fungal decay in the specimens. The wood specimens treated with the formulations used in termite resistance tests were more resistant against the termites when compared to specimens treated with the formulations in decay resistance tests. Even after severe weathering process, treated wood specimens showed resistance against the subterranean termites. Results suggest that essential oils and plant extracts might be important to develop new wood preservatives that are less harmful to the environment and humans than recently available ones. 相似文献
122.
Ryo Ishihara Shiho Asai Shigeyoshi Otosaka Shinsuke Yamada Hideyuki Hirota Kazuyoshi Miyoshi 《溶剂提取与离子交换》2013,31(2):171-180
An octadecylamino-group-introduced polymer chain grafted onto a porous sheet was impregnated with bis(2-ethylhexyl)hydrogen phosphate (HDEHP). A mixture of HDEHP and ethanol of various HDEHP concentrations was used for the impregnation. The porous sheet into which a C18H37NH group was introduced was immersed in HDEHP/ethanol solution before ethanol evaporation. The liquid permeability of a cartridge charged with the HDEHP-impregnated porous sheet in disk form prepared in 50 (v/v)% HDEHP/ethanol solution was 96% that of the starting-porous-disk-packed cartridge. The equilibrium binding capacity of the HDEHP-impregnated porous disk for yttrium ions was 0.32 mol per kg of the disk. In addition, the HDEHP-impregnated-porous-disc-packed cartridge was found to be applicable to the preconcentration of trace amounts of lanthanides in a multielement solution prior to their measurement by inductively coupled plasma mass spectrometry. 相似文献
123.
Kazuyoshi Yata 《Sequential Analysis》2013,32(4):463-482
We consider fixed-size estimation for a linear function of mean vectors from π i : N p (μ i , Σ i ), i = 1,…, k. The goal of inference is to construct a fixed-span confidence region with required accuracy. We find a new sample-size formulation and propose a two-stage estimation methodology to give the fixed-span confidence region satisfying the probability requirement approximately. We show that the proposed methodology greatly reduces the sample size to enjoy the asymptotic first-order consistency when the dimensionality p is extremely high. With the help of simulation studies, we show that the proposed methodology is still efficient even when p is moderate. We give an actual example to illustrate how it should be done by using the proposed methodology in the inference. 相似文献
124.
Mizue Munekata Seiichi Kimura Hiroaki Kurishima Jinsuke Tanaka Sohei Yamamoto Hiroyuki Yoshikawa Kazuyoshi Matsuzaki Hideki Ohba 《热科学学报(英文版)》2008,17(1):56-60
Recently, development of high technology has been required for the formation of thin uniform film in manufacturing processes of semiconductor as the semiconductor instruments become more sophisticated. Spin coating is usually used for spreading photoresist on a wafer surface. However, since rotating speed of the disk is very high in spin coating, the dropped photoresist scarers outward and reattaches on the film surface. A catch cup is set up outside the wafer in spin coating, and scattered photoresist mist is removed from the wafer edge by the exhaust flow generated at the gap between the wafer edge and the catch cup. In the dry process of a spin coating, it is a serious concern that the film thickness increases near the wafer edge in the case of low rotating speed. The purpose of this study is to make clear the effect of the catch cup geometry on the 3D boundary layer flow over the wafer surface and the drying rate of liquid film. 相似文献
125.
Yuichi Setsuhara Ken Cho Masaharu Shiratani Makoto Sekine Masaru Hori 《Thin solid films》2010,518(22):6492-6726
Plasma-polymer interactions have been investigated using atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS) of polyethyleneterephthalate (PET) films, which have been exposed to argon plasmas driven by low-inductance antenna modules as a parameter of ion energy. The AFM images indicated that the argon plasma exposure exhibited a significant change in surface roughness. The XPS analyses suggested that the degradation of chemical bonding structure and/or bond scission of PET could be effectively suppressed in the plasma exposures with ion energies below 6 eV. However, significant degradations of O = C-O bond, C-O bond and phenyl group were observed with increasing ion energy above 6 eV. 相似文献
126.
Tadao Shibuya Masahiro Yoshinaka Futoshi Utsuno Kazuyoshi Inoue Jung J. Kim Masaaki Obata 《Thin solid films》2010,518(11):3008-3011
The electronic structural analysis of the conductive transparent films was carried out using bulk sensitive hard X-ray photoelectron spectroscopy (HAXPES). The In2O3-ZnO film has amorphous structure before and after annealed, and the conduction band spectrum around Fermi level showed the similar spectra with that of as-deposited amorphous In2O3 film. In these amorphous films, the conduction band minimum locates at the deeper level than the crystalline In2O3 film. The electronic state which comes from randomness of amorphous structure possibly exists around this level or below. These electrons are expected to act as scattering center. We concluded that the electron mobility depends on the density of this electronic state. 相似文献
127.
MAMMOS(Magnetic Amplifying Magneto- Optical System:磁畴扩大磁光系统 )是实现高密度磁光盘的有效方法。不仅能得到不依赖于磁畴长度的较大的读出信号振幅,而且还能实现超出光学系统衍射极限的分辨率。过去,为实现磁畴的复印与扩大,要对记录膜面施加垂直方向的外部磁场。而现在得知,同时施加垂直磁场和水平方向的磁场,可大幅度地提高微小磁畴的读出特性。确认采用施加水平磁场的方法,在λ =635 nm, NA=0.55的条件下, 0.15μ m的连续磁畴也能获得 BER=2× 10- 4的读出效果。 相似文献
128.
129.
There is an alternative way for starting the design process of composite materials and structures (particularly, but not exclusively, aerospace structures) made from advanced composite laminate. It is based on sound fundamental understanding of the mechanisms by which damage accumulates with time in the laminate and structure across several orders of magnitude of size: fibre breakage and matrix cracking that lead progressively to ply fracture, followed by laminate cracking (delamination and splitting) that leads to component failure. Application of this approach to a predictive design methodology requires the identification and understanding of failure mechanisms in the material at the micron level of size and fracture of the component on the size scale orders of magnitude greater. 相似文献
130.
Numerical results of three-dimensional separated flow and heat transfer in a rectangular channel with a suddenexpansion are presented in this paper.Numerical simulations of Navier-Stokes and energy equations are carriedout using the finite difference method.The results of three-dimensional calculations are compared with thetwo-dimensional ones,and effects of the aspect ratio of channel upon the flow are shown.The transition fromsymmetric to asymmetric flow appears at lower Reynolds number as increasing the aspect ratio.The details oflocal heat transfer characteristics in two different separated flow regions on two downstream walls are clarified.Two-dimensionality of the flow and heat transfer almost disappears for the aspect ratio considered. 相似文献