研究者詳細 - 土川　覚

論文 - 土川　覚

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近赤外分光法による新しい考古計測学の確立査読有り

米延仁志, 土川覚

第20回記念非破壊分析シンポジウム講演要旨集 20 頁： 91 - 97 2004年

"Nondestructive measurement and analysis of physical properties for wood by near infrared spectroscopy" 査読有り

Tsuchikawa, S

MOKUZAI GAKKAISHI 50 巻 ( 3 ) 頁： A10 - A12 2004年

"Nondestructive measurement and analysis of physical properties for wood by near infrared spectroscopy" 査読有り

Tsuchikawa S

MOKUZAI GAKKAISHI 50 巻 ( 3 ) 頁： A10 - A12 2004年

"Nondestructive measurement and analysis of physical properties for wood by near infrared spectroscopy" 査読有り

Tsuchikawa S

MOKUZAI GAKKAISHI 50 巻 ( 3 ) 頁： A10 - A12 2004年

"Nondestructive measurement and analysis of physical properties for wood by near infrared spectroscopy" 査読有り

Tsuchikawa S

MOKUZAI GAKKAISHI 50 巻 ( 3 ) 頁： A10 - A12 2004年

"Nondestructive measurement and analysis of physical properties for wood by near infrared spectroscopy" 査読有り

Tsuchikawa, S.

MOKUZAI GAKKAISHI 50 巻 ( 3 ) 頁： A10 - A12 2004年

"Nondestructive measurement and analysis of physical properties for wood by near infrared spectroscopy" 査読有り

Tsuchikawa S

MOKUZAI GAKKAISHI 50 巻 ( 3 ) 頁： A10 - A12 2004年

近赤外分光法による木質系廃棄物の判別分析招待有り

"土川覚,山登香織"

木材保存 29 巻頁： 259-262 2003年11月

Near-infrared spectroscopic comparison of antique and modern wood

Yonenobu H, Tsuchikawa S

APPLIED SPECTROSCOPY 57 巻 ( 11 ) 頁： 1451 - 1453 2003年11月

Near-infrared spectroscopic comparison of antique and modern wood. 査読有り

Yonenobu H, Tsuchikawa S

Applied spectroscopy 57 巻 ( 11 ) 頁： 1451 - 3 2003年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Applied Spectroscopy

The temporal degradation of old wooden building material was estimated by using near-infrared (NIR) spectrometry. The difference second-derivative NIR spectra suggest that hemicellulose and holocellulose decreased while lignin increased relatively. It was revealed that nondestructive NIR spectroscopy is a useful technique in examining properties of antique wood.

DOI： 10.1366/000370203322554635

Scopus

PubMed

近赤外分光法による木質系廃棄物の判別分析招待有り査読有り

土川覚, 山登香織

木材保存 29 巻頁： 259-262 2003年11月

Application of near-infrared spectroscopy to wood discrimination 査読有り

Tsuchikawa S., Inoue K., Noma J., Hayashi K.

Journal of Wood Science 49 巻 ( 1 ) 頁： 29 - 35 2003年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Wood Science

This study deals with a new nondestructive discriminant analysis by which wood can be classified on the basis of a combination of near-infrared (NIR) spectroscopy and Mahalanobis' generalized distance. Its accuracy and reasonability were examined for wood samples with various moisture contents ranging from oven-dried to a fully saturated free water state. In a discriminant analysis employing second derivative spectra, each wood group was well distinguished. Mahalanobis' generalized distances between softwoods are relatively independent of analytical pattern, whereas the distances between hardwoods are large for easy classification. There may be two reasons for selecting a wavelength: (1) when the chemical component of wood substance relates to the discriminant analysis; and (2) when the difference in moisture content with wood species relates to them. When we correctly construct the database of NIR spectra, confirming the purpose of the analysis, suitable wood discrimination should be possible.

DOI： 10.1007/s100860300005

Scopus

Discriminant analysis of wood-based materials using near-infrared spectroscopy 査読有り

Tsuchikawa S., Yamato K., Inoue K.

Journal of Wood Science 49 巻 ( 3 ) 頁： 275 - 280 2003年10月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Wood Science

This study deals with the suitable discriminant techniques of wood-based materials by means of near-infrared spectroscopy (NIRS) and several chemometric analyses. The concept of Mahalanobis' generalized distance, K nearest neighbors (KNN), and soft independent modeling of class analogy (SIMCA) were evaluated to determine the best analytical procedure. The difference in the accuracy of classification with the spectrophotometer, the wavelength range as the explanatory variables, and the light-exposure condition of the sample were examined in detail. It was difficult to apply Mahalanobis' generalized distances to the classification of wood-based materials where NIR spectra varied widely within the sample category. The performance of KNN in the NIR region (800-2500nm), for which the device used in the laboratory was employed, exhibited a high rate of correct answers of validation (>98%) independent of the light-exposure conditions of the sample. When employing the device used in the field, both KNN and SIMCA revealed correct answers of validation (>88%) at wavelengths of 550-1010nm. These results suggest the applicability of NIRS to a reasonable classification of used wood at the factory and at job sites.

DOI： 10.1007/s10086-002-0471-0

Scopus

Discriminant analysis of wood-based materials using near-infrared spectroscopy

Tsuchikawa Satoru, Yamato Kaori, Inoue Kinuyo

Journal of wood science 49 巻 ( 3 ) 頁： 275 - 280 2003年6月

Discriminant analysis of wood-based materials using near-infrared spectroscopy 査読有り

TSUCHIKAWA Satoru, YAMATO Kaori, INOUE Kinuyo

Journal of Wood Science 49 巻 ( 3 ) 頁： 275 - 280 2003年6月

近赤外分光法の木材非破壊検査への応用招待有り

土川覚

木工機械 197 巻頁： 2-5 2003年6月

Near-infrared spectroscopic monitoring of the diffusion process of deuterium-labeled molecules in wood. Part I: Softwood

Tsuchikawa S, Siesler HW

APPLIED SPECTROSCOPY 57 巻 ( 6 ) 頁： 667 - 674 2003年6月

Near-infrared spectroscopic monitoring of the diffusion process of deuterium-labeled molecules in wood. Part II: hardwood. 査読有り

Tsuchikawa S, Siesler HW

Applied spectroscopy 57 巻 ( 6 ) 頁： 675 - 81 2003年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Applied Spectroscopy

Fourier transform near-infrared (FT-NIR) transmission spectroscopy was applied to monitor the diffusion process of deuterium-labeled molecules in hardwood (Beech). The results are compared with previous data obtained on softwood (Sitka spruce) in order to consistently understand the state of order in cellulose of wood. The saturation accessibility and diffusion rate varied characteristically with the OH groups in different states of order in the wood substance, the diffusants, and the wood species, respectively. The variation of saturation accessibility should be associated with the fundamental difference of the fine structure such as the microfibrils in the wood substance. The effect of the anatomical cellular structure on the accessibility was reflected in the variation of the diffusion rate with the wood species. The size effect of the diffusants also played an important role for the diffusion process in wood. Since the volumetric percentage of wood fibers and wood rays is relatively similar, the dichroic effects due to the anisotropy of the cellulose chains were apparently diminished. Finally, we proposed a new interpretation of the fine structure of the microfibrils in the cell wall by comparing a series of results from hardwood and softwood. Each elementary fibril in the hardwood has a more homogeneous arrangement in the microfibrils compared to that in the softwood.

DOI： 10.1366/000370203322005373

Scopus

PubMed

Near-infrared spectroscopic monitoring of the diffusion process of deuterium-labeled molecules in wood. Part II: Hardwood

Tsuchikawa S, Siesler HW

APPLIED SPECTROSCOPY 57 巻 ( 6 ) 頁： 675 - 681 2003年6月

Near-infrared spectroscopic monitoring of the diffusion process of deuterium-labeled molecules in wood. Part I: softwood. 査読有り

Tsuchikawa S, Siesler HW

Applied spectroscopy 57 巻 ( 6 ) 頁： 667 - 74 2003年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Applied Spectroscopy

The diffusion process of several molecules (D2O, n-butanol (OD) and t-butanol (OD)) In softwood (Sitka spruce) was investigated by means of a deuterium exchange method and Fourier transform near-infrared (FT-NIR) polarization spectroscopy. The location of OH groups in different states of order of cellulose in wood was clarified by analyzing the FT-NIR transmission spectra ranging from 7200 to 6000 cm-1. Four absorption bands were assigned to 2 × ν(OH) absorptions of the amorphous regions, OH groups in semicrystalline regions, and two types of intramolecular hydrogen-bonded OH groups in the crystalline regions, respectively. The saturation level of accessibility was very different for these absorption bands (i.e., 70-80, 60, and 40-50% for the amorphous, semi-crystalline, and crystalline regions, respectively). However, the saturation accessibilities for each absorption band varied little with molecular structure and geometry of the diffusants. The diffusion rate of D2O was much faster than that of n-butanol (OD) and t-butanol (OD) for all states of orders. The size effect of the butanols led to slight differences in the diffusive transport in the crystalline regions.

DOI： 10.1366/000370203322005364

Scopus

PubMed

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