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31.
The atmospheric deposition of reactive nitrogen on turf grassland in Tsukuba, central Japan, was investigated from July 2003
to December 2004. The target components were ammonium, nitrate, and nitrite ions for wet deposition and gaseous ammonia, nitric
and nitrous acids, and particulate ammonium, nitrate, and nitrite for dry deposition. Organic nitrogen was also evaluated
by subtracting the amount of inorganic nitrogen from total nitrogen. A wet-only sampler and filter holders were used to collect
precipitation and the atmospheric components, respectively. An inferential method was applied to calculate the dry deposition
velocity of gases and particles, which involved the effects of surface wetness and ammonia volatilization through stomata
on the dry deposition velocity. The mean fraction of the monthly wet to total deposition was different among chemical species;
37, 77, and 1% for ammoniacal, nitrate-, and nitrite-nitrogen, respectively. The annual deposition of inorganic nitrogen in
2004 was 47 and 48 mmol m−2 yr−1 for wet and dry deposition, respectively; 51% of atmospheric deposition was contributed by dry deposition. The annual wet
deposition in 2004 was 20, 27, and 0.07 mmol m−2 yr−1, and the annual dry deposition in 2004 was 35, 7.4, and 5.4 mmol m−2 yr−1 for ammoniacal, nitrate-, and nitrite-nitrogen, respectively. Ammoniacal nitrogen was the most important reactive nitrogen
because of its remarkable contribution to both wet and dry deposition. The median ratio of the organic nitrogen concentration
to total nitrogen was 9.8, 17, and 15% for precipitation, gases, and particles, respectively. 相似文献
32.
Akira Hoshino Maso Tsuji Masanori Momochi Akiko Mizutani Hideo Sawada Setsuo Kohnami Hiroki Nakagomi Michio Ito Hisato Saida Munehiro Ohnishi Michimasa Hirata Masao Kunioka Masahiro Funabash Shogo Uematsu 《Journal of Polymers and the Environment》2007,15(4):275-280
Several ISO standards for determining the ultimate aerobic/anaerobic biodegradability of plastic materials have been published.
In particular, ISO 14855-1 is a common test method that measures evolved carbon dioxide using such methods as continuous infrared
analysis, gas chromatography or titration and others (ISO 14855-1(2005.9)). This method is a small-scale test for determining
the ultimate aerobic biodegradability of plastic materials, where the amounts of compost inoculum and test sample in one tenth
comparing with that of ISO 14855-1. This method is well versed in ISO/DIS 14855-2 which the carbon dioxide evolved from test
vessel is determined by gravimetric analysis of carbon dioxide absorbent. The focus of this study is to elucidate statistically
the results of round robin test by seven countries used MODA, which were various deviations among the experiments. 相似文献
33.
We have found that giant hornets (Vespa mandarinia japonica) are killed in less than 10 min when they are trapped in a bee ball created by the Japanese honeybees Apis cerana japonica, but their death cannot be solely accounted for by the elevated temperature in the bee ball. In controlled experiments, hornets
can survive for 10 min at the temperature up to 47°C, whereas the temperature inside the bee balls does not rise higher than
45.9°C. We have found here that the CO2 concentration inside the bee ball also reaches a maximum (3.6 ± 0.2%) in the initial 0–5 min phase after bee ball formation.
The lethal temperature of the hornet (45–46°C) under conditions of CO2 concentration (3.7 ± 0.44%) produced using human expiratory air is almost the same as that in the bee ball. The lethal temperature
of the honeybee is 50–51°C under the same air conditions. We concluded that CO2 produced inside the bee ball by honeybees is a major factor together with the temperature involved in defense against giant
hornets. 相似文献
34.
Effect of the carbon coating in Fe-C-TiO(2) photocatalyst on phenol decomposition under UV irradiation via photo-Fenton process 总被引:1,自引:0,他引:1
Fe-C-TiO(2) photocatalysts which contained the residue carbon (0.2-3.3 mass%) were prepared from a mixture of TiO(2) and FeC(2)O(4) through the heating at 673-1173 K in Ar. These photocatalysts did not show a high adsorption of phenol, but they were active in photo-Fenton reactions during decomposition of phenol under UV irradiation with addition of H(2)O(2). It was proved that Fe(2+) governed the photoactivity of Fe-C-TiO(2) photocatalysts, it decreased with heat-treatment temperature above 773 K. For comparison, Fe-TiO(2) photocatalyst was prepared by heating TiO(2) and FeC(2)O(4) at 823 K in air for 3h. Phenol decomposition was going much slower on Fe-TiO(2) photocatalyst in comparison with Fe-C-TiO(2), of which mechanism was different, on the former phenol was decomposed by the radical reaction, on the latter through a complex reaction with iron and intermediates of phenol decomposition. Therefore carbon-coating TiO(2) was found to be advantageous for mounting iron and its application for the phenol decomposition via photo-Fenton process. 相似文献
35.
ABSTRACT: Long term trends in Japan's annual and monthly precipitation are investigated in this study. The statistical significance of a trend at a study site is assessed by the Mann‐Kendall (MK) test, and field significance of trends in climatic Regions II, III, and IV is evaluated using the bootstrap test preserving cross correlation. The practical significance of a trend is judged by a percentage change of the sample mean over an observation period. The field significance assessment demonstrates that annual precipitation in Region II did not show any significant change, but regional precipitation shifts occurred in different months. Precipitation significantly increased by 12.2 percent in May, while it significantly decreased by 12.0, 10.5, 15.6, and 19.7 percent, respectively, in April, September, October, and December. In Region III, annual precipitation declined by 11.8 percent, and monthly precipitation significantly decreased from September through January and in April, with the greatest decrease (38.2 percent) in December. In Region IV, significant reductions occurred in both annual precipitation (by 15.6 percent) and monthly precipitation from September through February and in June and July, with the worst reduction (44.7 percent) in December. 相似文献
36.
Ubiquity of parasporin-1 producers in <Emphasis Type="Italic">Bacillus thuringiensis</Emphasis> natural populations of Japan 总被引:1,自引:0,他引:1
Uemori A Maeda M Yasutake K Ohgushi A Kagoshima K Mizuki E Ohba M 《Die Naturwissenschaften》2007,94(1):34-38
Parasporin, a Bacillus thuringiensis parasporal protein, is unique in having a strong cytocidal activity preferential for human cancer cells. In this study, we
characterized parasporin activities associated with three novel geographical isolates of B.
thuringiensis. Parasporal inclusion proteins of the three isolates were highly toxic to human uterus cervix cancer cells (HeLa), but not
to non-cancer uterine smooth muscle cells (UtSMC). Inclusions of the isolates lacked insect toxicity and hemolytic activity
against sheep erythrocytes. Ouchterlony immunodiffusion tests revealed that the proteins of the three isolates are immunologically
closely related to parasporin-1 (Cry31A), but dissimilar to the three other existing parasporin groups. Our results provide
evidence that the parasporin-1-producing organism is a common member in B. thuringiensis populations occurring in natural environments of Japan. 相似文献
37.
Natsuko Ito Kondo Daisei Yamanaka Yuya Kanbe Yoko Kawate Kunitake Masahiro Yoneda Koji Tsuchida Koichi Goka 《Die Naturwissenschaften》2009,96(4):467-475
The European bumblebee, Bombus terrestris, is an invasive eusocial species whose distribution is expanding greatly beyond its native range because numerous colonies
are imported to or locally produced in non-native countries for pollination of agricultural crops. Closely related species
exist in Japan where the unrestricted import and use of B. terrestris has resulted in the establishment of wild colonies. Laboratory studies previously showed that B. terrestris and Japanese native species can copulate and produce fertilized eggs. Although these eggs do not hatch, the interspecific
mating can cause a serious reproductive disturbance to native bumblebees. In this study, we determined the frequencies of
interspecies mating between B. terrestris males and native bumblebee queens in the wild on the islands of Hokkaido and Honshu by analyzing the DNA sequences of spermatozoa
stored in spermathecae of native queens. We found that 20.2% of B. hypocrita hypocrita queens and 30.2% of B. hypocrita sapporoensis queens had spermatozoa of B. terrestris males in their spermathecae. Given that a Bombus queen generally mates only once in her life, such high frequencies of interspecific mating with B. terrestris pose serious threats to the populations of native bumblebees in Japan. 相似文献
38.
Yoshiaki Tsuzuki Masato Fujii Yasuo Mochihar Kouki Matsu Minoru Yoneda 《环境科学学报(英文版)》2010,22(6):892-897
The first social experiment program in Japan to reduce domestic wastewater pollutant discharge by “soft interventions” in households
has been conducted in the Yamato-gawa River drainage area since 2005. The Yamato-gawa River has been listed as one of the worst
water quality rivers in Japan because of the larger annual average BOD. “Hard interventions” including deployment of wastewater
treatment facilities and artificial installation of natural purification facilities in the river has been conducted in these years to improve
river water quality. At the first Yamato-gawa River social experiment program (YR-SEP) in March 2005, BOD at the monitoring point
near the river mouth decreased about 6% during the Program. Natural purification e ect along the river was evaluated in this article
with one-dimensional water quality model for the six river sections. Larger biological oxygen consumption rate, kb, was estimated in
the sections with artificially installed natural purification facilities. The e ect of “soft interventions” in households in the YR-SEP was
estimated as 25% BOD decrease in the nearest monitoring point to the river mouth, when all the households participate in the Program
and BOD discharge reduction rate with “soft interventions” in households was 40%. 相似文献
39.
We investigated the feeding habits and growth of juvenile stone flounder (Platichthys bicoloratus) in several estuarine nurseries in Sendai Bay, Japan. Prey abundance and composition and juvenile diet varied largely among
sites. However, polychaete palps (mostly Pseudopolydora kempi) and bivalve siphons (mostly Nuttallia olivacea) were positively selected and frequently consumed by juveniles, indicating the generality of sublethal feeding of juvenile
stone flounder in estuarine nurseries. Recent growth rates determined by otolith microstructure analyses were dependent on
juvenile body size and water temperature, but independent of juvenile density and food abundance. Growth rates were nearly
maximal from March to May, suggesting that food conditions are nearly optimal in these estuarine nurseries. Sublethal tissue
cropping of benthic invertebrates is thought to contribute largely to these high growth rates. 相似文献
40.
Global nuclear weapons tests fallout of 137Cs in the northern hemisphere has been documented in the UNSCEAR (United Nations Scientific Committee on the Effect of Atomic Radiation) reports. However, many questions have arisen during the past three to four decades; e.g. the water column inventory of 137Cs in the North Pacific Ocean was two to three time higher than the cumulative decay corrected fallout at the same latitude as stated in the UNSCEAR reports. Here we show more precise spatial distribution of global 137Cs fallout primarily on the basis of global measurements in rain, seawater and soil, as data from 10 degrees x 10 degrees grids. A typical feature of geographical distribution is that two high global 137Cs fallout areas exist in the northern hemisphere, where the highest 137Cs fallout was observed in the globe. These areas correspond to crossovers of areas where larger precipitation amounts were expected and where higher stratosphere-troposphere exchange was expected. Our new estimate of 765 +/- 79 PBq as global 137Cs fallout for the northern hemisphere is 1.4 times higher than that of 545 PBq in the UNSCEAR reports. 相似文献