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71.
72.
Takeshi Kawano Michio Aoyama Terry Joyce Hiroshi Uchida Yasushi Takatsuki Masao Fukasawa 《Journal of Oceanography》2006,62(6):777-792
An updated batch-to-batch difference table of IAPSO standard seawater (SSW) up to P145 is proposed. The batch-to-batch difference
table is based on several recent SSW comparison experiments, including the experiments conducted independently at the Japan
Agency for Marine-Earth Science and Technology (JAMSTEC) and Woods Hole Institute of Oceanography (WHOI) at about the same
time using the same procedure. Proposed batch-to-batch differences range from 1.2 × 10−3 to −1.9 × 10−3 with reference to the average of those from P91 to P102. Batch-to-batch differences from P29 to P145 with reference to the
recent batches and this average over every 5 years since 1960 are also presented, together with standard deviation. This reveals
that inconsistency among batches has improved since 1980s. In particular, the standard deviation was 0.3 × 10−3 in this decade, which is about one-half the value reported previously and almost equal to the modern measurement precision
(0.2 × 10−3) and is within-batch difference (<0.3 × 10−3). Proposed batch-to-batch differences were applied to the observational results of the WOCE hydrographic onetime section
(WHP onetime) in the Indian Ocean. Average absolute salinity differences at 14 crossover points in the Indian Ocean were slightly
larger, from 1.2 × 10−3 to 1.5 × 10−3, when the batch-to-batch difference table was applied; however, when results from the Indian, Pacific, and Atlantic Oceans
were combined, application of the batch-to-batch difference table yielded statistically acceptable salinity differences. The
table was also applied to WHP sections P1 and P17 (revisited about 10 years after the original observations during the WOCE
period) and sections I1, I7, and I8 (visited twice by different research vessels in the same year). In all cases, the table
corrected unrealistically large salinity changes in space and time. The results suggest that the application of the batch-to-batch
table to well-controlled salinity data such as WOCE datasets would be effective in making the datasets more consistent in
space and time. 相似文献
73.
74.
Mineralogy of the Boroo Gold Deposit in the North Khentei Gold Belt,Central Northern Mongolia
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Mineral assemblages and chemical compositions of ore minerals from the Boroo gold deposit in the North Khentei gold belt of Mongolia were studied to characterize the gold mineralization, and to clarify crystallization processes of the ore minerals. The gold deposit consists of low‐grade disseminated and stockwork ores in granite, metasedimentary rocks and diorite dikes. Moderate to high‐grade auriferous quartz vein ores are present in the above lithological units. The ore grades of the former range from about 1 to 3 g/t, and those of the latter from 5 to 10 g/t, or more than 10 g/t Au. The main sulfide minerals in the ores are pyrite and arsenopyrite, both of which are divisible into two different stages (pyrite‐I and pyrite‐II; arsenopyrite‐I and arsenopyrite‐II). Sphalerite, galena, chalcopyrite, and tetrahedrite are minor associated minerals, with trace amounts of bournonite, boulangerite, geerite, alloclasite, native gold, and electrum. The ore minerals in the both types of ores are variable in distribution, abundance and grain size. Four modes of gold occurrence are recognized: (i) “invisible” gold in pyrite and arsenopyrite in the disseminated and stockwork ores, and in auriferous quartz vein ores; (ii) microscopic native gold, 3 to 100 µm in diameter, that occurs as fine grains or as an interstitial phase in sulfides in the disseminated and stockwork ores, and in auriferous quartz vein ores; (iii) visible native gold, up to 1 cm in diameter, in the auriferous quartz vein ores; and (iv) electrum in the auriferous quartz vein ores. The gold mineralization of the disseminated and stockwork ores consists of four stages characterized by the mineral assemblages of: (i) pyrite‐I + arsenopyrite‐I; (ii) pyrite‐II + arsenopyrite‐II; (iii) sphalerite + galena + chalcopyrite + tetrahedrite + bournonite + boulangerite + alloclasite + native gold; and (iv) native gold. In the auriferous quartz vein ores, five mineralization stages are defined by the following mineral assemblages: (i) pyrite‐I; (ii) pyrite‐II + arsenopyrite; (iii) sphalerite + galena + chalcopyrite; (iv) Ag‐rich tetrahedrite‐tennantite + bournonite + geerite + native gold; and (v) electrum. The As–Au relations in pyrite‐II and arsenopyrite suggest that gold detected as invisible gold is mostly attributed to Au+1 in those minerals. By applying the arsenopyrite geothermometer to arsenopyrite‐II in the disseminated and stockwork ores, crystallization temperature and logfs2 are estimated to be 365 to 300 °C and –7.5 to –10.1, respectively. 相似文献
75.
Hiroaki Matsuo Masahide Kawano Koji Omori Kiyonori Nakajima Ichiro Takeuchi 《Marine pollution bulletin》2009,58(11):1615-1623
Organisms collected from a coastal ecosystem in Japan were analyzed for concentrations of 205 polychlorinated biphenyls (PCBs) congeners; analyses were guided by δ13C and δ15N measurements. The regression slopes of log PCB concentration on δ15N value are regarded as indices of biomagnification in food webs. The slope (wet weight basis) of ΣPCBs was +0.104; the slope (lipid weight basis) was close to zero. Lipid content increased from 0.06% in a primary producer to 8.32% in the highest trophic level consumer. Hence, biomagnification of ΣPCBs (wet weight basis) can be attributed to increase of lipid content through the food web. For most of the congeners, the slopes (wet weight basis) exceeded those (lipid weight basis) by ca. 0.10. Slopes increased with increasing PCB chlorination levels between chlorine numbers 1–6; slopes decreased at higher chlorination levels. This decrease is likely caused by a decrease in membrane permeability with increasing molecular weight. 相似文献
76.
Reiko Matsumoto Nguyen Phuc Cam Tu Shinsuke Haruta Masahide Kawano Ichiro Takeuchi 《Marine pollution bulletin》2014
We collected two subspecies of masu salmon: Oncorhynchus masou masou from four localities (southern Sea of Japan northward to Hokkaido) and O. masou ishikawae from upstream from Ise Bay close to a heavy industrial area. All 209 PCB congeners were analyzed using HRGC/HRMS. PCA ordination of congener concentrations divided data into three groups: (i) ssp. masou from Hokkaido, (ii) ssp. masou from the other regions and (iii) ssp. ishikawae. The highest ∑ PCB concentration (40.39 ng/wet wt) was in ssp. ishikawae followed by ssp. masou from southern waters; however the TEQdioxin-like PCBs was highest in ssp. masou from southern water (1.96 pg-TEQdioxin-like PCBs/g wet wt.) due to the high proportion of congener #126 in its complement (#126 has the highest toxic equivalency factor among congeners). There is likely a contamination source offshore in the southern Sea of Japan and/or along the migratory route of ssp. masou. 相似文献
77.
To constrain the timing of the tectonothermal events and formation process of a plutonic suite, U–Pb dating was carried out by laser ablation inductively coupled plasma mass spectrometry combined with cathodoluminescence imaging on zircon grains extracted from the Bato pluton, northern Yamizo Mountains, Japan. The Bato pluton consists of gabbro and diorite. Zircon grains separated from a gabbro sample had a unimodal 238U–206Pb age (105.7 ±1.0 Ma). It was interpreted as the solidification age of the gabbro. Cathodoluminescence observation showed that the zircon grains from a diorite sample were characterized by anhedral cores, oscillatory zoned mantles, and dark rims. The 238U–206Pb age of the anhedral cores ranged from 2 165 Ma to 161 Ma, indicating the assimilation of surrounding sedimentary rocks. The 238U–206Pb ages of the oscillatory zoned mantles and dark rims are 109.0 ±1.3 Ma and 107.7 ±1.3 Ma, respectively. Observation under polarizing microscopy suggests that the anhedral cores occurred before plagioclase and hornblende, and the oscillatory zones around the anhedral cores had crystallized at the same time as the crystallization of biotite. Moreover, the dark rims formed at the same time as the crystallization of quartz and K‐feldspar. The formation process of the gabbro‐diorite complex in the Bato pluton was inferred as follows. (i) A mafic initial magma intruded into Mesozoic sedimentary rocks, and the assimilation of these sedimentary rocks led to geochemical variation yielding a dioritic composition. Subsequently, plagioclase and hornblende of the diorite were crystallized before 109.0 ±1.3 Ma. (ii) Biotite crystallized in the middle stage around 109.0 ±1.3 Ma. (iii) Quartz and K‐feldspar of the diorite were crystallized at 107.7 ±1.3 Ma. The gabbroic magma solidified (105.7 ±1.0 Ma) after solidification of the diorite. 相似文献
78.
The solar neutron detector Space Environment Data Acquisition Equipment – Attached Payload (SEDA-FIB) onboard the International Space Station (ISS) detected several events from the solar direction associated with three large solar flares observed on 05 (X1.1), 07 (X5.4), and 09 (M6.3) March 2012. In this study, we focus on the interesting event of 05 March, present the temporal profiles of the neutrons, and discuss the physics that may be related to a possible acceleration scenario for ions above the solar surface. We compare our data with images of the flares obtained by the ultraviolet telescope Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). 相似文献
79.
Steric sea level changes estimated from historical ocean subsurface temperature and salinity analyses 总被引:13,自引:0,他引:13
Masayoshi Ishii Masahide Kimoto Kenji Sakamoto Sin-Iti Iwasaki 《Journal of Oceanography》2006,62(2):155-170
An historical objective analysis of subsurface temperature and salinity was carried out on a monthly basis from 1945 to 2003
using the latest observational databases and a sea surface temperature analysis. In addition, steric sea level changes were
mainly examined using outputs of the objective analyses. The objective analysis is a revised version of Ishii et al. and is
available at 16 levels in the upper 700 m depth. Artificial errors in the previous analysis during the 1990s have been worked
out in the present analysis. The steric sea level computed from the temperature analysis has been verified with tide gauge
observations and TOPEX/Poseidon sea surface height data. A correction for crustal movement is applied for tide gauge data
along the Japanese coast. The new analysis is suitable for the discussion of global warming. Validation against the tide gauge
reveals that the amplitude of thermosteric sea level becomes larger and the agreement improves in comparison with the previous
analysis. A substantial part of local sea level rise along the Japanese coast appears to be explained by the thermosteric
effect. The thermal expansion averaged in all longitudes from 60°S to 60°N explains at most half of recent sea level rise
detected by satellite observation during the last decade. Considerable uncertainties remain in steric sea level, particularly
over the southern oceans. Temperature changes within MLD make no effective contribution to steric sea level changes along
the Antarctic Circumpolar Current. According to statistics using only reliable profiles of the temperature and salinity analyses,
salinity variations are intrinsically important to steric sea level changes in high latitudes and in the Atlantic Ocean. Although
data sparseness is severe even in the latest decade, linear trends of global mean thermosteric and halosteric sea level for
1955 to 2003 are estimated to be 0.31 ± 0.07 mm/yr and 0.04 ± 0.01 mm/yr, respectively. These estimates are comparable to
those of the former studies. 相似文献
80.
A nonlinear search algorithm for optimizing constrained design of ship structures is presented. The decision variables can be continuous or discrete and the constraints can be homogeneous or inequality nonlinear functions of those variables. The algorithm does not use gradients; therefore, it can work with non-systematized functions such as tables or another class of design routine. It was tested in the structural design of a Patrol Boat and has proved to be a powerful tool decreasing the time expended in preliminary design when it is done by the conventional spiral approach. 相似文献