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This review paper reports near-infrared (NIR) imaging studies using a newly-developed NIR camera, Compovision. Compovision can measure a significantly wide area of 150 mm×250 mm at high speed of between 2 and 5 s. It enables a wide spectral region measurement in the 1 000~2 350 nm range at 6 nm intervals. We investigated the potential of Compovision in the applications to industrial problems such as the evaluation of pharmaceutical tablets and polymers. Our studies have demonstrated that NIR imaging based on Compovision can solve several issues such as long acquisition times and relatively low sensitivity of detection. NIR imaging with Compovision is strongly expected to be applied not only to pharmaceutical tablet monitoring and polymer characterization but also to various applications such as those to food products, biomedical substances and organic and inorganic materials.  相似文献   
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Abstract

Spin-spin relaxation of 23Na-NMR is observed by the spin echo method at room temperature for Y-type zeolite loaded with Na metal without hydration. For saturated and no levels of loading, the echo decay is well fitted by single exponential function. T 2 decreases to be 0.25 times smaller by loading. This decrease of T 2 is explained semiquantitatively with assuming nuclear dipole-dipole interaction between neighboring Na.  相似文献   
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In this paper, we prove that certain parametrized multiple series satisfy the same relation as Ohno?s relation for multiple zeta values. This result gives us a generalization of Ohno?s relation for multiple zeta values. By virtue of this generalization, we obtain a certain equivalence between the above relation among the parametrized multiple series and a subfamily of the relation. As applications of the above results, we obtain some results on multiple zeta values.  相似文献   
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Y Igarashi  A Yamakawa  C Kim  N Ikeda 《Radioisotopes》1987,36(10):501-504
Several human lung samples were dissected into lobes and uranium and silicon contents in each lobe were determined by the fission track method and the inductively coupled plasma-atomic emission spectrometry (ICP-AES), respectively. It was found that both uranium and silicon concentrations were high in the upper lobe compared with those in the lower one. Though the tendency may be mainly interpreted by the deposition way of airborne dust in the lung, the higher U/Si concentration ratio in the upper part than that in the lower part of lungs may suggest the partial removal of uranium deposited in the lower part of the tissue.  相似文献   
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The synthesis and photophysical properties of a rosamine-based fluorescent chemosensor, RosAg, for detecting Ag ion in an aqueous solution are described. This fluorescent sensor has a negligible quantum yield (<0.005) in the absence of Ag(+), whereas a significant increase in fluorescence is observed upon complexation with Ag(+) under physiological conditions. The crystal structure of the silver complex with the chelator moiety of RosAg reveals a trigonal-planar coordination geometry in which three S atoms occupy the metal center. Although a strong coordinative interaction of Ag-N is not observed in the crystal structure, the (1)H NMR experiments suggest that aniline nitrogen is likely to be associated with the Ag(+) center in the solution state. This may inhibit the photoinduced electron transfer process and result in the enhancement of fluorescence.  相似文献   
18.
The major element composition, including two kinds of clay minerals and moisture content of sound-producing sand are reported for the first time. Sand from 33 beaches in Japan has been found to make sound. Ten sound-producing beaches were selected to compare with silent beach sand. Both sound-producing sand and silent beach sand are mostly composed of quartz and feldspar. The range of SiO2 content of sound-producing sand is not different from silent sand samples. This indicates that a high quartz content is not necessary to produce sound, although more than 60 weight percent of quartz is necessary. One silent sand recovered its sound after a 3.5 percent HNO3 treatment. Also, a small portion of clay minerals was found. A clean grain surface is a necessary factor for sand to produce sound. Illite was found in all silent sand samples.  相似文献   
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137Cs in seawater is one of the most powerful tracers of water motion. Large volumes of samples have been required for determination of 137Cs in seawater. This paper describes improvement of separation and purification processes of 137Cs in seawater, which includes purification of 137Cs using hexachloroplatinic acid in addition to ammonium phosphomolybdate (AMP) precipitation. As a result, we succeeded the 137Cs determination in seawater with a smaller sample volume of 10 liter by using ultra-low background gamma-spectrometry in the Ogoya underground facility. 137Cs detection limit was about 0.1 mBq (counting time: 106 s). This method is applied to determine 137Cs in small samples of the South Pacific deep waters.  相似文献   
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