Milling and polishing are important operations during the production of white rice. The degree of milling and polishing has a significant effect on the nutritional aspects of white rice, especially on minerals, due to a non-uniform distribution of nutrients in the kernel. Information on the distribution of nutrients in rice will greatly help to understand the effect of milling and aid in designing procedures that improve technological and sensory properties of rice while retaining its essential nutrients as much as possible. In this study, three kernel shapes (short-, medium-and long-grain) of rice were selected for the study of milling characteristics and distribution of zinc (Zn) and phytic acid using abrasive milling and X-ray fluorescent microscope imaging approaches. Milling characteristics differed with kernel shapes and cultivars. Mass loss (y, %) correlated well with milling duration (x, s) and was fitted using a polynomial equation of y = ax 2 +bx+c (R 2 =0.99). Different kernel shapes of rice resulted in different patterns. Breakage in milling increased with longer duration of milling. The relation between breakage (y, %) and milling duration (x, s) fitted the exponential equation y = ae bx. Levels of phytic acid, as well as Zn decreased with prolonged milling. Phytic acid decreased at a higher rate than Zn. The analysis of different milling runs showed that the concentration of phytic acid decreased from the surface region inward, whereas X-ray fluorescent images indicated that the highest concentration of phosphorus was at the interface of embryo and perisperm. Our results help to understand the milling characteristics of different rice cultivars. Understanding these characteristics offers opportunities to optimize milling procedures for maximum phytate removal, at minimum mineral losses and yield loss.

Micro-XRF is a significant tool for the analysis of small regions. A micro-X-ray beam can be created in the laboratory by various focusing X-ray optics. Previously, nondestructive 3D-XRF analysis had not been easy because of the high penetration of fluorescent X-rays emitted into the sample. A recently developed confocal micro-XRF technique combined with polycapillary X-ray lenses enables depth-selective analysis. In this paper, we applied a new tabletop confocal micro-XRF system to analyze several forensic samples, that is, multilayered automotive paint fragments and leather samples, for use in the criminaliztics. Elemental depth profiles and mapping images of forensic samples were successfully obtained by the confocal micro-XRF technique. Multilayered structures can be distinguished in forensic samples by their elemental depth profiles. However, it was found that some leather sheets exhibited heterogeneous distribution. To confirm the validity, the result of a conventional micro-XRF of the cross section was compared with that of the confocal micro-XRF. The results obtained by the confocal micro-XRF system were in approximate agreement with those obtained by the conventional micro-XRF. Elemental depth imaging was performed on the paint fragments and leather sheets to confirm the homogeneity of the respective layers of the sample. The depth images of the paint fragment showed homogeneous distribution in each layer expect for Fe and Zn. In contrast, several components in the leather sheets were predominantly localized.

We have realized the first enantioselective organocatalytic Diels-Alder reaction between alpha-substituted acroleins, such as alpha-acyloxyacroleins, and not only cyclic but also acyclic dienes. alpha-Acyloxyacroleins are useful as synthetic equivalents of alpha-haloacroleins. The present catalyst could be prepared in situ from pentafluorobenzenesulfonic acid (2.5-3.0 equiv) and chiral triamine (1 equiv) derived from H-l-Phe-l-Leu-N(CH2CH2)2. The enantioselective Diels-Alder reaction of 5-(benzyloxymethyl)cyclopentadiene, cyclopentadiene, cyclohexadiene, 2,3-dimethylbutadiene, and isoprene with alpha-(p-methoxybenzoyloxy)acrolein catalyzed by the above chiral ammonium salt (2.5-20 mol %) at -20-22 degrees C gave the corresponding adducts with 83, 83, 91, 92, and 88% ee, respectively.

A new 3D-XRF instrument was developed with a fine-focus X-ray tube. The depth resolution of the developed instrument was 13.7 mm at the energy of Au Lb (11.4 keV). Compared with the previous 3D-XRF instrument developed in the author's research group, the depth resolution was improved by a factor of 3-4. A small dependence of depth resolution on X-ray energy was also confirmed for the new instrument. The depth resolution was varied from 22.6 mm to 13. 7 mm for an energy range from 5.4 keV to 11.4 keV, respectively. A few layered materials were measured by two (previous and new) 3D-XRF instruments. As expected, the new 3D-XRF instrument gave a depth profile with a high-resolution. In addition, a 3D-structured material was proposed and developed to evaluate the 3D-imaging performance. The material consisted of two cylindrical patterns of Au having a micrometre-scale structure. Elemental imaging performance was compared by using this 3D-structured material for two different 3D-XRF instruments.

We report the first example of an organocatalytic enantioselective [2 + 2] cycloaddition reaction of unactivated alkenes with α-acyloxyacroleins to give optically active 1-acyloxycyclobutanecarbaldehydes and subsequent ring expansion to give optically active 2-hydroxycyclopentanone derivatives. Organoammonium salt, H-L-Phe-L-Leu-N(CH2CH2)2-reduced triamine•2.6HNTf2, is a highly effective chiral catalyst for the above enantioselective [2 + 2] cycloaddition. Thus, we have developed a novel and useful formal enantioselective [2 + 3] cycloaddition through two steps.