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101.
Akihiro Kuroda Pascal Joly Naoki Shibata Hikari Takeshige Kouichi Asakura 《Journal of the American Oil Chemists' Society》2008,85(6):549-553
An organic–inorganic hybrid composite for use as a coating agent was prepared by mixing linseed oil with hydrophobic octylsilyl
titanium dioxide particles having an average diameter of 35 nm (OSI-TIO2-35) in volatile silicone. The weight ratio of linseed
oil with OSI-TIO2-35 was varied from 2:8 to 8:2 and the mixture was spread on a glass plate by dragging an applicator across
it. After storing in the oven at 60 °C for 2 days, the composite having the weight ratio of OSI-TIO2-35 with linseed oil at
8:2 exhibited very high water-repellent properties having a water contact angle of 148°. Variation of the water contact angle
during storage at 60 °C was monitored. It decreased by 10° in the initial 8 h and then increased by 45° over the next 2 days.
Composites containing silicone resin, TMSS BY11-018, instead of linseed oil were also prepared. The sample having a weight
ratio of OSI-TIO2-35 with TMSS BY11-018 at 8:2 also exhibited very high water-repellent properties with a water contact angle
of 152°. The highly hydrophobic surface thus prepared by the coating and drying of those organic-inorganic hybrid composites
was easily transferred to highly hydrophilic surfaces by calcination at 500 °C for 3 h. 相似文献
102.
Iida K Uematsu Y Suzuki K Yasuno T Hirata K Ito K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2007,48(4):112-117
Properties of eight commercial licorice extracts used as a food additive (sweetener, listed in the List of Existing Food Additives in the Japanese Food Sanitation Law) were surveyed. Residue on ignition ranged from 0.3 to 12.4%, and pH ranged from 4.1 to 6.8, amount of glycyrrhizin, which is the major component in licorice extract, ranged from 10.9 to 77.4%, sodium ranged from 0.1 to 1.2%, potassium ranged from 0.3 to 5.0%, and ammonium nitrogen ranged from 0.03 to 2.5%. These results indicated that various products were distributed on the market. Differences in the manufacturing process may contribute to the variations of product properties. 相似文献
103.
Three-dimensional shift selectivity of a reflection-type hologram with speckle shift recording is investigated experimentally and numerically. We build an experimental setup consisting of lenses with numerical apertures of 0.28 and an iron-doped LiNbO(3) with a thickness of 0.5 mm. The experimental results show that three-dimensional selectivity has a size of 0.97 microm x 0.97 microm x 8.8 microm in diffraction efficiency. We also develop a volume holographic memory simulator to evaluate the experimental results. The simulator can quantitatively evaluate bit error rate, signal-to-noise ratio, and diffraction efficiency. Numerical results are in good agreement with the experimental results. The experimental and numerical results indicate that three-dimensional shift multiplexing can increase the storage capacity. 相似文献
104.
We propose a numerical method to obtain complex amplitude distribution of a three-dimensional (3D) object from a digital hologram. The method consists of two processes. The first process is to measure simultaneously a hologram of the 3D object and an object intensity distribution by two image sensors. These intensity distributions give us the amplitude and absolute value of phase of the 3D object at the image sensor plane. The second process is the determination of phase distribution by a proposed iterative process based on the criterion that the reconstructed 3D object is in focus and its conjugate reconstruction is out of focus. Numerical and experimental results show the effectiveness of the proposed method. 相似文献
105.
Numerical simulations of non-premixed turbulent combustion of CH4–H2 mixtures using the PDF approach
Lotfi Ziani Abla Chaker Khaled Chetehouna Ali Malek Bouziane Mahmah 《International Journal of Hydrogen Energy》2013
The present work is devoted to the study of non-premixed turbulent combustion with the PDF approach using three turbulence models: k-? model, modified k-? model and RSM model. A detailed kinetic mechanism is used in the numerical simulations. The three turbulence models are compared and evaluated with the experimental data and the numerical results of the literature. The evaluation concludes that the modified k-? is the most appropriate for simulating this kind of flame. A study of the effect of hydrogen addition on methane combustion is performed. Hydrogen addition causes the elevation of combustion temperature, the decreasing of CO and CO2 mass fractions but leads to the increase of NO mass fraction. 相似文献
106.
ABSTRACTIn this study, we investigated the effects of heat-affected zone (HAZ) softening on the strength and elongation of resistance spot-welded joints in high-strength steel sheet in an in-plane tensile test. The fracture in the softened HAZ had a little effect on the maximum stress of the resistance spot-welded specimen; however, the fracture elongation decreased. The nugget diameter and HAZ softened width had little effect on the fracture elongation of the resistance spot-welded specimen. Also, the fracture elongation decreased slightly with the decrease in the sheet thickness. The major factor affecting the fracture elongation was the HAZ hardness ratio (= Softened HAZ/Base metal × 100%). For the resistance spot-welded specimen with a thickness of 1.6 mm, when the HAZ hardness ratio decreased to less than 80%, the fracture position changed from the base metal to the softened HAZ and the fracture elongation decreased sharply. In addition, with a decrease in the hardness ratio, the fracture elongation decreased. 相似文献
107.
Amina Ben Abla Guilhem Boeuf Ahmed Elmarjou Cyrine Dridi Florence Poirier Sylvie Changotade Didier Lutomski Abdellatif Elmselmi 《International journal of molecular sciences》2021,22(14)
Engineering of biomimetic motives have emerged as promising approaches to improving cells’ binding properties of biomaterials for tissue engineering and regenerative medicine. In this study, a bio-adhesive ligand including cell-binding domains of human fibronectin (FN) was engineered using recombinant protein technology, a major extracellular matrix (ECM) protein that interacts with a variety of integrins cell-surface’s receptors and other ECM proteins through specific binding domains. 9th and 10th fibronectin type III repeat containing Arginine-Glycine-Aspartic acid (RGD) and Pro-His-Ser-Arg-Asn (PHSRN) synergic site (FNIII9-10) were expressed in fusion with a Colored Multi Affinity Tag (CMAT) to develop a simplified production and characterization process. A recombinant fragment was produced in the bacterial system using E. coli with high yield purified protein by double affinity chromatography. Bio-adhesive surfaces were developed by passive coating of produced fragment onto non adhesive surfaces model. The recombinant fusion protein (CMAT-FNIII9/10) demonstrated an accurate monitoring capability during expression purification and adsorption assay. Finally, biological activity of recombinant FNIII9/10 was validated by cellular adhesion assay. Binding to α5β1 integrins were successfully validated using a produced fragment as a ligand. These results are robust supports to the rational development of bioactivation strategies for biomedical and biotechnological applications. 相似文献
108.
Tsuguhiko Nakagawa Takahiro Nishi Yu Notoji Yoshiaki Kawakami Masayuki Tanino Yoshio Abe Kasumi Ito Kenji Marumo Toshiyuki Aoyama Yoshinori Itaya Kouichi Nakaso Jun Fukai 《能源与动力工程:英文版》2014,(4):589-595
Reducing CO2 emissions and restraining dependence on nuclear power generation are serious concerns in the prevention of global warming since the Great East Japan Earthquake. To do so, it is necessary to use and expand natural renewable energy source such as solar energy and to promote energy conservation. However, in high-latitude regions, it is difficult to directly and effectively use solar power due to on insufficient amount of solar radiation. If steam can be generated from warm water at less than 373 K, it is possible to obtain steam by solar water heaters from weak solar radiation and industrial waste warm water without the consumption of any fossil fuels. In this study, the authors have been developing a system which generates steam over 423 K from warm water at less than 373 K using an adsorption heat pump with zeolite. Therefore, bench-scale equipment which generates steam continuously and the experimental results are mentioned. 相似文献
109.
Antioxidants play a vital role in protecting the skin from environmental distress. As the skin is constantly exposed to harmful UV radiation, endogenous antioxidants present in the superficial layers of the skin neutralize reactive oxygen species. Over time, antioxidants become depleted and loss their protective effect on the skin. Therefore, supplementing skin with topical antioxidant can help replenish this loss and fight the oxidative stress. The objective of this study was to deliver antioxidants topically and quantify the amount permeated in the stratum corneum and underlying skin. Polyphenols (catechin, resveratrol and curcumin) and vitamin (retinol) with various lipophilic properties were delivered via porcine ear skin, using propylene glycol as a vehicle. The amount in the stratum corneum and underlying skin was quantified using tape stripping and skin extraction methods, respectively, and samples were analysed via HPLC. All four antioxidants permeated into the skin from the propylene glycol vehicle. The order of the amount of antioxidant in the stratum corneum was catechin > resveratrol~ retinol> curcumin, whereas that in the underlying skin was retinol > catechin~ resveratrol~ curcumin. Of the total amount of polyphenols in the skin, approximately 90% was retained in the stratum corneum whereas 10% was quantified in the underlying skin. In contrast, 10% of retinol was retained in the stratum corneum whereas 90% permeated in the underlying skin. Polyphenols (catechin, resveratrol and curcumin) showed high concentration in the stratum corneum whereas retinol showed high accumulation in the underlying layers of the skin. 相似文献
110.
Satoshi Wada Kenta Yamashita Ichiro Fujii Kouichi Nakashima Nobuhiro Kumada Chikako Moriyoshi Yoshihiro Kuroiwa 《Ceramics International》2013
Barium titanate (BaTiO3, BT)–potassium niobate (KNbO3, KN) (BT–KN) nanocomplex ceramics with various KN/BT molar ratios were prepared by the solvothermal method. From a transmittance electron microscopy (TEM) observation, it was confirmed that KN layer thickness of the BT–KN nanocomplex ceramics was controlled from 0 to 44 nm by controlling KN/BT molar ratios. Their dielectric constants were measured at room temperature and 1 MHz, and a maximum dielectric constant of around 400 was measured for the BT–KN nanocomplex ceramics with a KN thickness of 22 nm. TEM observation revealed that below KN thickness of 22 nm, BT/KN heteroepitaxial interface was assigned to the strained interface while over 22 nm, the interface was assigned to the relaxed one. These results suggested that the strained heteroepitaxial interface could be responsible for the enhanced dielectric constants. 相似文献