Swirling Cavity Flow of water through a Straight Circular Pipe 1

Article信州大学工学部紀要 32: 1-10 (1972)departmental bulletin pape

Swirling. Cavity Flow of Water through a Straight Circular Pipe 2

Article信州大学工学部紀要 32: 11-22 (1972)departmental bulletin pape

Application of Polysaccharide-Based Chiral High-Performance Liquid Chromatography Columns for the Separation of Regio-, E/Z-, and Enantio–Isomeric Mixtures of Allylic Compounds

Daicel Chiralpak IA, IB, and IC, which are the polysaccharide-based chiral stationary phase (CSP) columns for high-performance liquid chromatography (HPLC), were applied in the separation of the non-enantiomeric isomeric mixtures obtained by the various allylation reactions and were highly effective in separating the regio- and (E)/(Z)-isomers in the allylation products. Due to the close structural similarity of the isomeric allylic compounds in the reaction mixtures, separations of the isomers are laborious and could not be accomplished by the conventional methods such as silica gel column chromatography, silica gel HPLC, preparative GPC, distillation, and so forth. This study has shown potential advantages of using the polysaccharide-based CSP columns in the separation of not only enantiomeric but also non-enantiomeric isomeric mixtures

Developing an Online Learning Material for Kanji Vocabulary

Although foreign students who come to Japan are highly motivated to learn the Japanese language, they often meet with great difficulties that set them back. Mastering the reading and writing of the kanji vocabulary seems to present especially great hardships to them. Therefore, it is very important to provide a learning environment that will enable them to engage in serious learning wherever and whenever they wish. For this reason, we decided to develop an online learning program that will motivate and assist self-learners. In this paper, we will discuss the significance of this software system, describe the system\u27s structure, and summarize the program

Tailored surface porosities on ceramic foams

Novel ceramic foams with tailored surface porosities have been prepared by direct blowing of powder compact, and followed by modulated gas release from the blown bodies. The processing methodologies to produce precisely controlled pore configuration have been discussed in terms of: the direct blowing of powder compacts with a phenoric resin, to form an array of interconnected spherical pores with various unique surfaces comprised of relatively denser, zebra-stripe type (denser and porous) and highly oriented grains, to provide improved mechanical strength and sufficient fluid permeability, that has been created by using one-pot blowing process. These simple and versatile approaches can be used to tailor pore configurations, and fabricate macroporous monoliths with various distinct characteristics

Contamination profiles of antifouling biocides in selected coastal regions of Malaysia

The concentrations of butyltins (BTs) in sediment from Peninsular Malaysia along the Strait of Malacca and their spatial distribution are discussed. The concentrations of BTs were high in the southern part of Peninsular Malaysia where there is a lot of ship traffic, because trade is prosperous. The concentrations of monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) in sediment from the coastal waters of Peninsular Malaysia were in the range 4.1-242 microg/kg dry weight (dw), 1.1-186 microg/kg dw, and 0.7-228 microg/kg dw, respectively. A higher percentage of TBT was observed in the area where TBT concentrations were high. The concentrations of monophenyltin (MPT), diphenyltin (DPT), and triphenyltin (TPT) were in the range <0.1-121 microg/kg dw, 0.4-27 microg/kg dw, and 0.1-34 microg/kg dw in sediment from Peninsular Malaysia, respectively. MPT was the dominant phenyltin species. MBT, DBT, and TBT in green mussel (Perna viridis) samples were detected in the range 41-102 microg/kg, 3-5 microg/kg, and 8-32 microg/kg, respectively. A tolerable average residue level (TARL) was estimated at 20.4 microg/kg from a tolerable daily intake (TDI) of 0.25 microg TBTO/kg body weight/day. The maximum value of TBT detected in green mussel samples was the value near the TARL. TPTs were not detected in green mussel samples. The concentrations of Diuron and Irgarol 1051 in sediment from Peninsular Malaysia were in the range <0.1-5 microg/kg dw and <0.1-14 microg/kg dw, respectively. High concentrations of these compounds were observed in locations where the concentrations of TBT were high. Sea Nine 211, Dichlofluanid, and Pyrithiones were not detected in sediment. The concentrations of antifouling biocides in Melaka and the Strait of Johor were investigated in detail. BTs were found in similar concentrations among all sampling sites from Melaka, indicating that BT contamination spread off the coast. However, Sea Nine 211, Diuron, and Irgarol 1051 in the sediment from Melaka were high at the mouth of the river. BT concentrations at the Strait of Johor were higher than those in Peninsular Malaysia and Melaka and were high at the narrowest locations with poor flushing of water. The concentrations of antifouling biocides were compared among Malaysia, Thailand, and Vietnam. A higher concentration and wide variations of TBT and TPT in sediment from Malaysia were observed among these countries. The Irgarol 1051 concentrations in sediment from Malaysia were higher than those in Thailand and Vietnam

Biological effects of low concentrations of tributyltin on the caprellid amphipod Caprella danilevskii

In order to examine the biological effects of tributyltin (TBT), experiments involving the exposure of 5 levels of TBT concentrations (0, 10, 100, 1000 and 10000 ngl^) were conducted on the caprellid amphipod Caprella danilevskii, both over a generation after hatching (50 days) and embryonic stage (5 days). In TBT exposure after hatching, marked delays in growth and molting during the early developmental stage and mature stage were found in both 100 and 1000ng TBTCll^ concentrations in spite of the sex. All specimens died in 10000 ng TBTCll^ within 4 days after hatching. Inhibition of maturation and reproduction such as delaying in the achievement of maturity and a decrease in the number of juveniles hatched was apparent in 10 and 100ng TBTCll^ concentrations. Furthermore, brood loss, and failure in egg formation and hatching were observed as the TBT concentration became higher. No significant changes in sex ratio were seen in response to TBT exposure after hatching. A drastic decrease in survival rate was observed at 10ng TBTCll^ which corresponds to the mean level in coastal waters. In embryonic exposure, although the female proportion was 36% of the total in the control, its proportion increased up to 80% at 100 and 1000ngl^ in the hatched juvenile. All specimens died in 10000 ngTBTCll^ within 5 days after spawning due to the acute toxic concentration for the species. No significant differences were observed to occur in the sex ratio in response to the exposure after hatching (50 days) in a previous study. Sex disturbance might therefore be induced during the embryonic stage in the caprellid. Reproductive inhibitions such as brood loss and oogenesis inhibition occurred even at 10-100 ng TBTCll^ exposures in the short-term period in both parental females and their offspring females. The embryo survival rate in the offspring decreased drastically as the TBT concentrations increased, with the decrease being observed at TBT concentrations as low as 10ngl^ during 5 days. In parental females, the survival rate also decreased at more than 100ng TBTC ll^, despite transfer into the no TBT-added seawater after 5 days. Therefore, our data suggest that nanogram concentrations TBT exposure, both short- and long-term, in the coastal environment might critically damage the life history characters of caprellids, and may influence populations of C. danilevskii in the coastal ecosystem