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151.
Takatsuki S Nemoto S Sasaki K Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(2):89-95
An LC/MS method was developed for the determination of acrylamide (AA) in processed or cooked foods. AA was extracted with a mixture of water and acetone from homogenized food samples after the addition of 13C-labeled acrylamide (AA-1-(13)C) as an internal standard. The extract was concentrated, washed with dichloromethane for defatting, and cleaned up on Bond Elut C18, PSA and ACCUCAT cartridge-columns, and then AA was determined by LC/MS in the selected ion recording (SIR) mode. For the LC/MS analysis, four LC columns were connected in-line and the flow of the mobile phase was switched according to a time-program. Monitoring ions for AA were m/z 72 and 55, and those for AA-1-(13)C were m/z 73 and 56. AA and AA-1-(13)C were determined without interference from the matrices in all samples. The recoveries of AA from potato chips, corn snack, pretzel and roasted tea spiked at the level of 500 ng/g of AA were 99.5-101.0% with standard deviations (SD) in the range from 0.3 to 1.6%. The limits of detection and quantification of the developed method were 9 and 30 ng/g for AA in samples, respectively. The method was applied to the analysis of AA in various processed or cooked food samples purchased from retail markets. High levels of AA were found in potato chips and French-fried potato (467-3,544 ng/g). Fried and sugar-coated dough cakes (karinto) contained 374 and 1,895 ng/g. Corn snacks contained 117-535 ng/g of AA. Roasted foods (such as roasted sesame seed, roasted barley (mugi-cha), roasted tea (hoji-cha), coffee beans and curry powder) contained 116-567 ng/g of AA. Foods made from fish, egg and meat contained lower levels of AA than the plant-based foods. Foods containing much water showed a tendency to have low levels of AA compared with dry foods. The proposed method was applicable to the analysis of AA in variety of processed foods. 相似文献
152.
Ichikawa S Akita T Okumura M Haruta M Tanaka K Kohyama M 《Journal of electron microscopy》2003,52(1):21-26
Three-dimensional (3-D) nanostructures of gold catalysts supported on TiO2 were analysed by electron holography and high-resolution electron microscopy. The contact angle of the gold particle on TiO2 tended to be >90 degrees in the case of gold particles with a size (height) of >4 nm and it tended to be <90 degrees for gold particles with a height of <2 nm. The change in morphology increases the perimeter at the Au/TiO2 interface as the particle size decreases. This change in 3-D structure should be attributed to a change in electronic structure at the interface. It was found that electron holography enabled 3-D analysis at the atomic level and was effective for analysing nanostructured particles. 相似文献
153.
The authors have developed a software tool, MolSpace, to visualize massive molecular datasets. MolSpace can project a set of massive multivariate data onto a visual space (two- or three-dimensional space) by means of principal component analysis. MolSpace allows users not only to draw a scatter diagram of the data but also to display their two- or three-dimensional molecular structures as the objects in that space. With a probe (a molecular object) the user can navigate vast data spaces, thus facilitating understanding of the data structure. In addition, partial space searching is also available that is based on similarity searching techniques. It is possible to interrogate a three-dimensional structure of a chemical compound that corresponds to each object on the space in real time. The detail of the system is discussed with an illustrative example. 相似文献
154.
This article demonstrates the self-replication and self-organization phenomena based on a reaction–diffusion mechanism by
computer simulation. The simulation model consists of a one-dimensional cell array. Each cell contains two kinds of chemical
substances, activator u and inhibitor v, that can generate a reaction–diffusion wave, which is a spatial concentration pattern. The cells are supposed to be divided
or deleted depending on the concentrations of chemical substances. We tried several kinds of diffusion coefficient in the
model, and in some simulations, a self-replication process and a generating cell array with a metabolic process were observed.
By applying the division rule and the apoptosis rule, cell arrays duplicate in two oscillating states, i.e., self-replication
processes were observed. By applying a division rule and an annihilation rule, a cell array that has a stable length is generated
by changing the cell components, i.e., generating a cell array by a metabolic process was observed. Surprisingly, these two
phenomena are realized independently of the initial number of cells.
This work was presented in part at the 11th International Symposium on Artificial Life and Robotics, Oita, Japan, January
23–25, 2006 相似文献
155.
Fu-Ying Huang Satoshi Yamamoto Eric Baugh Tetsuo Semba 《Microsystem Technologies》2007,13(8-10):849-857
A new approach to analyze HDD seeking acoustics is proposed. An acoustic transfer function was derived that has seeking current as input and seeking acoustics as response. The derivation and the advantage and limitation of this acoustic transfer function approach is discussed in details in this paper. HDD seeking acoustics is mainly determined by the seeking current spectrum and the mechanical design. The acoustics transfer function represents the mechanical design, and was used to diagnose trouble mechanical modes and to guide servo design to reduce specific seeking current frequency content. The acoustic transfer function approach also enables quick performance prediction of combination of different mechanical designs and seeking currents. Various HDDs with different seeking current profiles and mechanical designs were evaluated experimentally and numerically. Finally, a new seeking servo algorithm was evaluated, and good agreement was shown between the numerical prediction using the acoustics transfer function approach and the measured seeking acoustics. 相似文献
156.
Seiichi Takami Teruyuki Sato Tahereh Mousavand Satoshi Ohara Mitsuo Umetsu Tadafumi Adschiri 《Materials Letters》2007,61(26):4769-4772
We synthesized surface-modified iron oxide nanoparticles in aqueous phase by heating an aqueous solution of iron sulfate (FeSO4) at 473 K with a small amount of either n-decanoic acid (C9H19COOH) or n-decylamine (C10H21NH2), which is not miscible with water at room temperature. Transmission electron microscopy showed that the addition of n-decanoic acid or decylamine changed the shape of the obtained nanoparticles. X-ray diffraction spectra revealed that the synthesized nanoparticles were in α-Fe2O3 or Fe3O4 phase while Fourier transform infrared spectroscopy and thermogravimetry indicated the existence of an organic layer on the surface of the nanoparticles. In the synthetic condition, decreased dielectric constant of water at higher temperature increased the solubility of n-decanoic acid or n-decylamine in water to promote the reaction between the surface of iron oxide nanoparticles and the organic reagents. After the synthesis, the used organic modifiers separated from the aqueous phase at room temperature, which may help the environmentally benign synthesis of surface-modified metal oxide nanoparticles. 相似文献
157.
Tsunehiko Sugawara Takahiro Murakami Yuichi Kuroki Mikio Ueki Takeshi Naraki Yasumasa Kato Satoshi Kanasugi 《Journal of the Society for Information Display》2007,15(1):39-47
Abstract— A new design for an FED envelope, composed of box‐shaped front glass, sheet‐like rear glass, and metal members, has been devised. This design structure is effective in reducing tensile stress induced by vacuum at the sealing points. Also, a new glass composition, a new physical tempering method, and a lead‐free hermetic sealing material have been developed. As a result, a novel lightweight spacer‐free panel structure for FEDs has been developed by integrating these new technologies. It will assist in maximizing the essential advantages of FED such as high image quality, high reliability, and low cost. 相似文献
158.
Cuiling Li Bo Jiang Hungru Chen Masataka Imura Liwen Sang Victor Malgras Yoshio Bando Tansir Ahamad Saad M. Alshehri Satoshi Tominaka Yusuke Yamauchi 《Nano Research》2016,9(6):1752-1762
Mesoporous Au films consisting of a network of interconnected Au ligaments around ultra-large pores were found to exhibit a promising electrocatalytic activity towards sluggish reactions. Mesoporous Au films with pore sizes up to 25 nm were successfully fabricated using a polymeric micelle approach. A superior catalytic activity of the mesoporous Au films towards methanol oxidation was confirmed, which was thoroughly analyzed and compared with that of other Au materials. An intrinsic investigation on the high catalytic activity revealed that the superior performance of the as-prepared mesoporous Au film was related to its unique atomic structures around the mesopores with well-crystallized facets and several step/kink sites on the Au surfaces. These findings showcase a strategic and feasible design for preparing highly active Au-based catalysts that could be used as promising candidates in electrocatalytic applications. 相似文献
159.
160.
Cooling load is a heat value of cold water used for air conditioning in a district heating and cooling system. Cooling load prediction in a district heating and cooling system is one of the key techniques for smooth and economical operation. In this article, cooling load prediction in such a district heating and cooling system is considered. Unfortunately, since actual cooling load data usually involve measurement noises, outliers, and missing data for several reasons, a prediction method considering the effect of the outliers and missing data is desirable. In this article, a new prediction method using a simplified robust filter to improve a numerical stability problem of a robust filter and a three-layered neural network, is proposed. Applications of the proposed method and some other methods to actual cooling load data in a district heating and cooling system involving outliers and missing data show the usefulness of the proposed method. 相似文献