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21.
22.
The general-relativistic equations of hydrodynamics for a nonideal fluid are derived in the modified Lagrangian form. Together with the zeroth and first moment equations of radiative transfer derived by Morita and Kaneko (1986), the equations provide a complete set of the modified Lagrangian equations of radiation hydrodynamics. The equations of hydrodynamics are specialized for a thermally conducting, Newtonian viscous fluid in the modified Lagrangian form, which are the generalization of the specialrelativistic equations of hydrodynamics derived by Greenberg (1975). 相似文献
23.
Tributyltin and triphenyltin induce spermatogenesis in ovary of female abalone,Haliotis gigantea 总被引:1,自引:0,他引:1
Horiguchi T Kojima M Kaya M Matsuo T Shiraishi H Morita M Adachi Y 《Marine environmental research》2002,54(3-5):679-684
Two-month flow-through exposure experiments of tributyltin (TBT) and triphenyltin (TPhT) were conducted with abalone, Haliotis gigantea. Nominal concentrations of 100 ng TBT/l and 100 ng TPhT/l caused significant spermatogenesis in ovaries of exposed females. There were also significantly more contracted primary oocytes observed in females exposed to either TBT or TPhT than controls. The incidence of two types of unknown cells was also significant in females exposed to TPhT. No significant histological changes were observed in testis of exposed males. This ovarian spermatogenesis caused by TBT and/or TPhT resembles gastropod imposex. Remarkably high concentrations of TBT and TPhT were observed in the head (including central nervous system ganglia), compared to muscles concentrations. Accumulation of TBT and TPhT in the head may disturb reproductive hormonal regulators through neuropeptides released from ganglia. This, as well as possible aromatase inhibition, may be one of the inducers for spermatogenesis in the abalone ovaries. 相似文献
24.
Hikokazu Morita 《Geochimica et cosmochimica acta》1975,39(2):218-220
The p-hydroxyacetophenone ester of palmitic acid has been isolated from a sphagnum peat. Although fatty acids and phenolic compounds are common components of peat, naturally occurring phenolic esters of fatty acids are rare. 相似文献
25.
Landslides in Sado Island of Japan: Part I. Case studies, monitoring techniques and environmental considerations 总被引:1,自引:0,他引:1
Lulseged Ayalew Hiromitsu Yamagishi Hideaki Marui Takami Kanno 《Engineering Geology》2005,81(4):419-431
A sufficient knowledge on the kinematics and development of landslides helps to adopt proper measures that can be used to protect slopes and the environment in general. This can be achieved by adequate monitoring programs. This paper presents the findings of intensive monitoring activities carried out on Shiidomari and Katanoo landslides found in Sado Island of Japan. More than one year of observation of the two landslides allowed defining some peculiar futures of their kinematics and style of development. The problem of slope instability in the two areas is generally accredited to various factors. But, both landslides were triggered by heavy rainfalls and snowmelt. Because of the outline of the area and the presence of relict topographic features, the Shiidomari landslide is considered to be a large-scale reactivation of old slope failures. The Katanoo landslide is, however, a first-time case. Geophysical investigations and drilling activities in Shiidomari indicated the presence of two slip planes. The deepest (80–100 m) of these is controlled by existing lineaments. Monitoring data suggests that the body of the landslide has subsided as much as 1.16 m just below the main scarp, but a centimeter in the central region. The toe sector also experienced a significant amount of subsidence, but this was counter-balanced by an uplift on the opposite side of the landslide. Hence, the landslide seems not any more active along the deepest slip surface, although it may extend upward and define a series of shallow shear planes around the crown. In the case of Katanoo, the landform characteristics, differential weathering, the road cut and groundwater fluctuations appeared to contribute much to determine the exact location of the landslide. Extensional cracks that preceded the landslide can be related to heavy rainfalls and the cold and warm cycles thereafter. Subsurface investigations and monitoring works indicated that the landslide has two slide blocks with different slip planes. During the observation period, the upper part of the landslide responded more effectively to rainfall and snowmelt than the middle and lower sections. The corresponding movements, however, appeared to settle about three months after failure. There were also little strain transmissions in boreholes and no significant change in the characteristics of the landslide. The kinematics of deformation of many of the slopes in Sado Island resembles that of Shiidomari landslide. But mass movements along highways and mountain roads are usually similar to Katanoo. Landslides of the type like Shiidomari may not show sudden and drastic failures, but are usually long lasting and can reactivate repeatedly along new, shallow shear planes. Monitoring works and long-term supervisions in these types of landslides are useful to identify impending failures and take the right measures before they brought about large-scale destruction to the environment. 相似文献
26.
Intensive measurements of gas and aerosol for 2 weeks were carried out at Qingdao (gas and aerosol in 2000, 2001 and 2002), Fenghuangshan (gas and aerosol in 2000 and 2001), and Dalian (aerosol in 2002) in the winter–spring period. High SO2 episodes were observed on 18 January 2000 at both Qingdao and Fenghuangshan. According to back trajectory calculations and analysis of gaseous species, high SO2 episodes were caused by local pollution and transport.Nitrate, sulfate and ammonium were the major species in PM2.5. Mass fractions of NO3−, nss-SO42− and NH4+ at Qingdao in 2002 were 10%, 12% and 5.5% for PM2.5, respectively, which were higher than that of nss-Ca2+ (1%). Chemical compositions observed at Dalian and Fenghuangshan were similar to those at Qingdao. The mass ratio of nss-SO42−/SO2 at Qingdao in winter was low (< 1.2), indicating that sulfate was probably produced by the slow oxidation of SO2 in the gas phase and/or was transported from outside of Qingdao in winter. The equivalent ratio of NH4+ to nss-SO42− was 1.39, suggesting that ammonium sulfate was one of the major chemical compositions in PM2.5. The NO3−/SO42− ratio at Qingdao was higher than that at remote places in East Asia. Gas and aerosol data obtained at Fenghuangshan were similar to data at Qingdao, suggesting that emissions from small cities may have a great influence on pollution in northern China. 相似文献
27.
Y. Kondo W. A. Matthews A. Iwata Y. Morita M. Takagi 《Journal of Atmospheric Chemistry》1987,5(1):37-58
Aircraft observations of oxides of nitrogen (NO y ), measured with a ferrous sulfate converter, over the sea surrounding the Japanese islands (30–43° N, 131–141° E) were carried out in the winter of 1983 and 1984 at altitudes mostly between 3 and 8 km. NO y defined here is the sum of NO, NO2, and other unstable oxides of nitrogen that are converted to NO by ferrous sulfate. The main observations were:
- Over the Pacific Ocean between the latitudes of 30–35° N, the observed NO y mixing ratio between 3 and 8 km was a fairly constant 200 pptv. The NO mixing ratio increased with altitude from 15 pptv at 3 km to 35 pptv at 7 km.
- Over the Sea of Japan, tropospheric NO y mesured between 1 and 6 km started increasing with latitude North of 35° N and reached about 1000 pptv at 40° N.
- NO y was measured in an air mass transported from the stratosphere near a tropopause fold region. When the ozone mixing ratio was between 80 and 140 ppbv, the NO y mixing ratio was about 200 pptv.
28.
A point explosion with thermal radiation in an axially symmetric inhomogeneous medium is investigated by generalizing the method of Laumbach and Probstein to include the effects of radiative cooling. As an example, a point explosion in the plane stratified transparent medium with exponential density distribution is calculated. It is shown that the focusing effect along the symmetry axis is enhanced by radiative cooling effect. Explosion models of extragalactic double radio sources are briefly discussed. 相似文献
29.
Horiguchi T Kojima M Takiguchi N Kaya M Shiraishi H Morita M 《Marine pollution bulletin》2005,51(8-12):817-822
Histological examination of gonads as well as chemical analysis of organotin compounds in tissues of the giant abalone, Haliotis madaka, was conducted to evaluate continuing endocrine disruption in abalone populations in Japan. Abalone specimens were collected from two different areas, Tsushima as a reference site and Jogashima as a site representative of declining abalone populations where serious organotin contamination had been observed, each month from January 1998 to March 1999. Scores were given to the development stages of reproductive cells in the ovary and testis. The degree of sexual maturation was evaluated by calculating the mean value of a histogram of these scores for the reproductive cells of each abalone. The temporal variations in degree of sexual maturation showed that female and male abalone from Tsushima matured synchronously, while those from Jogashima did not, which were similar to results of the previous study during September 1995–November 1996. Approximately 19% of the female abalone from Jogashima were masculinized with an ovo-testis, which was also similar to the result of the previous study. The masculinization of female abalone is reported to be induced by tributyltin (TBT) and triphenyltin (TPhT) from antifouling paints. Concentrations of the sum of butyltins (TBT, dibutyltin (DBT) and monobutyltin (MBT): ΣBTs) and the sum of phenyltins (TPhT, diphenyltin (DPhT) and monophenyltin (MPhT): ΣPhTs) in the muscle of abalone from Jogashima (n = 73) of 7.8 ± 9.0 ng/g wet wt. and 4.5 ± 6.8 ng/g wet wt., respectively, were significantly higher than those from Tsushima (n = 87) of 4.7 ± 4.9 ng/g wet wt. and 0.8 ± 1.7 ng/g wet wt., respectively (p < 0.05 for ΣBTs; p < 0.001 for ΣPhTs), although concentrations of TBT and TPhT in the muscle of abalone from Jogashima (n = 73) of 2.2 ± 2.5 ng/g wet wt. and 5.8 ± 5.1 ng/g wet wt., respectively, were insignificantly and significantly higher than those from Tsushima (n = 87) of 0.4 ± 0.6 ng/g wet wt. and 0.5 ± 0.9 ng/g wet wt., respectively, (p > 0.05 for TBT; p < 0.001 for TPhT). Thus, endocrine disruption as well as contamination by organotins in the giant abalone from Jogashima is still persisting. 相似文献
30.
Hα and HeI emission in the jets of pre-main sequence stars – implications for the heating mechanisms
M. Takami A. Chrysostomou J. Bailey T.M. Gledhill M. Tamura H. Terada 《Astrophysics and Space Science》2003,287(1-4):143-146
Jets and winds in pre-main sequence (PMS) stars are often heated and ionized, and understanding their heating mechanism is desired to compare UV-to-IR spectral signatures with models and thus investigate their driving mechanism. We review our results of long-slit spectroscopy and spectro-astrometry for He I 1.083 μm and Hα emission, and investigate the heating mechanisms in the jet in the outer (>10 AU) and inner (<10 AU) regions, respectively. 相似文献