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21.
Geographic ranges of marine intertidal organisms are not entirely governed by discontinuities in temperature gradients. This is especially true in the eastern north Pacific Ocean, where temperature gradation is less steep than in the western north Atlantic Ocean. The southern limit of distribution of Littorina sitkana (Philippi, 1845) and the northern limit of L. planaxis (Philippi, 1847) occur at Charleston, Oregon (Latitude 43.4°N). No discontinuity in air or water temperature can be correlated with these distributional boundaries. A third species, L. scutulata (Gould, 1849), has the widest range, overlapping with L. planaxis in the south and L. sitkana in the north (Latitude 27.5° to 58°N). L. planaxis transplanted to northern Washington survived for 4 years, grew and produced planktonic larvae. Either larval mortality or south-flowing currents during planktonic life prevent this species from dispersing northward. L. sitkana has direct development and occurs only in habitats where adults are sheltered from waves and egg masses from desiccation. Lack of suitable habitat, coupled with the presence of the predatory crab Pachygrapsus crassipes (Randall, 1839) prevent the southward establishment of L. sitkana.  相似文献   
22.
The relationship between otolith length and body length (total length) was examined in walleye pollock Theragra chalcogramma (Pallas), collected from Pacific Ocean waters adjacent to Hokkaido, Japan, and in larvae reared from fertilized eggs. A linear relationship was found between log-transformed body length and otolith length data with two inflection points at ca. 11 mm and 100 mm total length. This relationship was found to be applicable also to samples from the Japan Sea, Bering Sea and Okhotsk Sea. The early growth pattern estimated by back-calculation of otolith increments of 1-yr fish from Funka (Uchiura) Bay (Hokkaido) accorded with that obtained from size-at-age data of 0 yr fish collected in the preceding year. Differences were found in comparisons of the back-calculated early growth pattern between samples from waters adjacent to Hokkaido, the Pacific Ocean, the Japan Sea and the Okhotsk Sea. The growth curve of the Okhotsk samples was markedly different from others, showing rapid initial growth up to about 100 d after hatching and attaining a small body size in the first year.  相似文献   
23.
Paper passes through many hands. In the present paper, key parts of this cycle in Japan were examined, using questionnaire surveys of households and paper makers. The study aimed to examine the paper makers' strategy for paper production and their attitude to recycling, in comparison with those of the consumers. The study especially focused on toilet paper because consumers have a lot of freedom in purchasing toilet paper. A total of 1242 consumers and 60 paper makers responded. The major findings were as follows. First, we compared the criteria of consumers for purchasing toilet paper with the conjectures of paper makers. Brand, advertisements and the appearance of shopping displays received 60% support from paper makers, but less than 12% of consumers selected these criteria even if we exclude those who do not buy toilet paper or do not have any particular criteria. On the other hand, multiple plies and benefit to the earth were selected by moderate numbers (between 20 and 25%) of consumers, while only 16.77 and 5.69%, respectively of paper makers marked these criteria. Paper makers strongly believe that many retailers sell toilet paper as a loss-leader. By comparing those matters considered important for recycling by consumers with those considered important by makers, it was shown that many makers have a clear awareness of the particular problem, the lack of used paper consumption, in the current paper recycling situation in Japan.  相似文献   
24.
Environmental Science and Pollution Research - The corrected Electronic Supplementary Material is presented in this paper.  相似文献   
25.
Blast pressure is a major source of the damage caused by an accidental gas explosion. Its magnitude depends on the thermal expansion rate and hence on the flame propagation velocity. This paper discusses the influence of two flame instability mechanisms, i.e., diffusive-thermal and hydrodynamic instabilities, on flame propagation velocity with an emphasis on their scale effects as the flame continuously increases its size during an explosion. The Sivashinsky equation is numerically solved to simulate flame propagation behaviors. It is found that flame propagation velocity, Vf, is independent of flame size under the influence of diffusive-thermal instability, whereas Vf increases with flame size under the influence of hydrodynamic instability. The latter result is understood as a result of flame’s fractal structure. Fractal dimension is determined from the dependency of Vf on flame size, and the obtained fractal dimension is close to the known experimental value.  相似文献   
26.
Rate coefficients are reported for the gas-phase reaction of the hydroxyl radical (OH) with C2HCl3 (k(1)) and C2Cl4 (k2) over an extended temperature range at 740+/-10 Torr in a He bath gas. These absolute rate measurements were accomplished using a laser photolysis/laser-induced fluorescence (LP/LIF) technique under slow flow conditions. The simple Arrhenius equation adequately describes the low temperature data for k1 (<650 K) and the entire data set for k2 and is given by (in units of cm3 molecule(-1) s(-1)): k1(291 - 650 K) = (9.73+/-1.15) x 10(-13) exp (158.7+/-44.0)/T, k2(293 - 720 K ) = (1.53+/-0.14) x 10(-12) exp (-688.2+/-67.5)/T. Error limits are 2sigma values. The room temperature values for k1 and k2 are within +/-2sigma of previous data using different techniques. The Arrhenius activation energies for k1 and k2 are a factor of 2-3 lower than previously reported values. The experimental measurements for both k1 and k2 in conjunction with transition state and variation transition state theory calculations infer an OH addition mechanism. The lack of a measurable kinetic isotope effect for k1 is consistent with this mechanism. Insight into the subsequent reactions of the chemically activated intermediate are presented in the form of potential energy diagrams derived from ab initio calculations.  相似文献   
27.
Although snappers (Lutjanidae) are commercially important fishery resources in tropical and subtropical waters, their home range size and its spatial arrangement have not been sufficiently clarified. In the present study, the size and spatial arrangement of the home range of the reef-associated checkered snapper Lutjanus decussatus (Lutjanidae) were investigated by use of a portable GPS receiver. In a 120 m × 120 m quadrat established on a section of the fringing reef of Ishigaki Island, 29 individuals of the species were identified by their color pattern and individuals were divided into five arbitrary size classes (class 1 <10 cm TL ≤ class 2 <15 cm TL ≤ class 3 <20 cm TL ≤ class 4 <25 cm TL ≤ class 5). Fish tracking by snorkeling was conducted with the portable GPS receiver. Site fidelity of this species was high. Home range size ranged from 93.0 to 3638.4 m2, and there was a significant positive correlation between the home range size and fish total length. Home ranges of the same-sized individuals abutted each other (8.8% area overlap), whereas those of different-sized individuals overlapped (44.0% area overlap). Agonistic behavior (attack and agonistic display) was more frequently found among same-sized individuals (times of agonistic behavior/times of all encounters × 100 = 71.3%), whereas such agonistic behavior was rarely found among different-sized individuals (times of agonistic behavior/times of all encounters × 100 = 6.9%). These results suggest that home ranges of Lutjanus decussatus can be regarded as territories against same-sized individuals, but not different-sized individuals. The usefulness of the fish tracking by snorkeling using a portable GPS receiver for home range size estimation and the function of the overlapping territory of the species are discussed.  相似文献   
28.
It has been recognized that the involvement of local community is essential to ensure the sustainability of A/R CDM (afforestation/reforestation clean development mechanism) project. This study verifies if the risks of non-permanence and leakage are addressed in a registered small scale A/R CDM project in Vietnam. Workshops, interviews, and a questionnaire survey of local villagers revealed that the project has caused a shortage of land for conventional activities such as grazing, fuel wood collection and shifting cultivation, and consequently posed the risks of project non-permanence and leakage. It is suggested that participation of all stakeholders in the community to the A/R CDM project beyond existing land tenure and adequate carbon benefit sharing according to the level of contribution to the project are required to reduce the risk of non permanence. To ensure the participation, the community should have capability such as consensus building and collective action. Leakage would be minimized if the community has alternative measures to the conventional activities before starting the project. We argue that it is necessary to first develop a community’s capabilities in the readiness phase of any A/R CDM project in order to reduce the risks for the project sustainability, and that new sources of funding are needed for this purpose.  相似文献   
29.
The effect of silica sand on the diffusion of sodium ions in mixtures of montmorillonite and silica sand was studied by measuring the apparent diffusion coefficients, activation energies for diffusion, and the basal spacing of the mixed samples. These diffusion experiments suggest that the apparent diffusion coefficients of sodium ions in the mixed samples were almost the same as those of pure montmorillonite samples having the same partial dry densities of montmorillonite. The activation energy dependence for diffusion of sodium ions on the partial dry density was different between the mixed samples and the pure montmorillonite samples. The activation energy increased by adding silica sand at the partial dry density of 1.0 Mg m(-3), and decreased by adding silica sand at the partial dry densities higher than 1.2 Mg m(-3). A change in the XRD profile was observed after adding silica sand at the partial dry density of 1.6 Mg m(-3). Here, a three-water-layer hydrate state of montmorillonite was found in the mixed sample whereas only a two-water-layer hydrate state was observed in the pure montmorillonite sample. These experimental results suggest that silica sand changed the montmorillonite microstructure in the mixed samples, which then altered the sodium-ion diffusion process.  相似文献   
30.
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