Investigation of chlorophylls as a scavenger of manganese(II) and zinc(II) using a radiotracer technique

Uptake of manganese(II) and zinc(II) by chlorophylla (Chl) was investigated using a radiotracer technique in order to elucidate its ability of scavenging metals released into the soil environment. Two possibilities were considered for the metal uptake: (1) substitutional complexation with Chl and (2) inclusion of the metals into Chl aggregates. It was found that manganese(II) was not trapped appreciably by both Chl itself and its aggregates. Magnesium of Chl was exchanged with zinc(II) in aqueous phase giving Zn−Chl at pH values higher than 7. Zinc(II) was found to be trapped by Chl aggregates depending on the pH of the aqueous phase.     

Depth-adaptive regularized reconstruction for reflection diffuse optical tomography

We study reflection diffuse optical tomography using two-dimensional (2D) continuous-wave source-detector arrays on the surface of semi-infinite medium, aiming at imaging the perfusion and the hemoglobin oxygen saturation variation of human cerebral cortex with brain activation. We had previously formulated the inverse problem with Moore-Penrose inversion. When we use simple regularization in this inverse problem, the reconstruction sensitivity decreases markedly with the depth so that the signal in the deep range may be masked by an unwanted signal in the shallow range. In this paper, we propose a depth-adaptive regularized reconstruction, in which we assign a smaller regularization parameter with the depth. We demonstrate improvement of the three-dimensional (3D) reconstruction uniformity using the proposed scheme.     

Detection of multiple anions by thin-layer chromatography

A novel detection method for 21 different anions by thin-layer chromatography is presented. Anions on the target plate form salts with amine in a developing solvent and are visualized after staining with citric acid-acetic anhydride reagent as white spots contrasting against a pale red-pink background. This method has particularly high sensitivity for anions of chlorate, sulfate, phosphate, chromate and dichromate (0.02-0.05 microg). The method is demonstrated to efficiently detect toxic arsenite in curry sauce as an example application. The proposed method offers highly efficient indirect detection for a wide range of anions, and serves as a purification procedure for the preparation of anionic sample solutions for other analytical methods.     

Surface modification without desorption: recycling of Cl on Si(100)-(2 x 1)

We demonstrate chlorine-induced modification of Si(100)-(2 x 1) under conditions where Cl is recycled rather than desorbed as SiCl2. A dimer with 2 Cl atoms, 2SiCl, converts to SiCl2+Si, allowing the bare Si atom to escape onto the terrace. At temperatures below the desorption threshold, the SiCl2 unit decays through Cl diffusion, allowing the second Si atom to escape. The result is a dimer vacancy, terrace regrowth structures, and Cl that is able to participate in another pitting event. Access to this unexpected roughening pathway is controlled by the Cl concentration and temperature. This previously overlooked process represents an important component of Si(100) surface processing.     

The design secret of Kyokusui-no-En’s meandering channel

The purpose of this study is to investigate the characteristics of the flow through the Jonangu channel which is used for ceremonial game called as ‘Kyokusui-no-En’ in Japanese. The geometry of the channel is measured, a visualization technique is used to measure the actual flow characteristics, and then a numerical flow model is used to represent the flow including unsteady flow characteristics. Numerical model of drifting cup is introduced to investigate an interaction between flow and motion of the cup. Finally, the intention of the channel design is interpreted from the viewpoint of fluid mechanics using observed and calculated results.     

Optical excitation of trapped electrons into continuum in naphthalene single crystal

Wavelength dependence of the photocurrent in irradiated naphthalene single crystal was measured and a broad band peaked at 1.8 eV was found. This band was ascribed to the transition of a charge carrier trapped by the radical into a continuum. The width of the continuum was determined as 0.63^+0.2_-0.05 eV.     

Surface-induced valley-splitting in n-channel (001) silicon-MOS charge layer

The surface-induced valley-splitting theory by Sham and Nakayama is shown in the special case of a two-band model for the silicon band structure to be closely related to the electric break-through effect of Ohkawa and Uemura. Recent criticisms of our theory by Ohkawa are shown to be erroneous.     

?rganometallischer Komplex mit Lewis-Base. 3. Mitt. Polymerisationsmechanismen von Vinylverbindungen durch Al-Alkyl-Lewis-Basen-Komplex

Ohne Zusammenfassung