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71.
Measurements of aerosol size-separated number concentrations were performed in March 2001 on the Tama Hills of Japan, located
near regions of heavy industry. The concentrations of particles larger than 1.0 μ m in diameter dramatically increased during
the Kosa phenomena on 6–8 and 18–24 March. The number concentrations of coarse particles (> 3.0 μm) showed distinct diurnal
variations, especially during the Kosa events. Fine particles smaller than 0.5 μm increased when the relative humidity was
high and the wind speed was low. On the other hand, the coarse particles concentrations were well correlated with wind speed
and temperature. The dry deposition velocity of the coarse particles at the forest canopy was estimated from the nighttime
decrease in the number concentrations. 相似文献
72.
Satoru Fujita Kenzi Suzuki Yasuo Shibasaki 《Journal of Material Cycles and Waste Management》2002,4(1):41-45
In this study, an attempt was made to synthesize hydrogrossular, a group of garnet minerals, under hydrothermal conditions
at temperatures below 180°C, using coal ash, which is the solid waste from thermal power plants, as a starting material. A
single phase corresponding to hydrogrossular was found at around 120°C, and the hydrogrossular coexisted with 11-Å tobermorite
above 140°C. The hydrogrossular phase decreased with increasing reaction temperature, while that of 11-Å tobermorite increased
concurrently. The physicochemical properties of the hydrogrossular obtained from the hydrothermal synthesis was characterized
by X-ray diffraction thermogravimetry/differential thermal, analysis, scanning electron microscopy, Fourier transform infrared
spectroscopy, and X-ray fluorescence spectroscopy.
Received: September 4, 2000 / Accepted: March 7, 2001 相似文献
73.
Yoshida Y Ito A Murakami M Murakami T Fujimoto H Takeda K Suzuki S Hori M 《Journal of the Air & Waste Management Association (1995)》2007,57(10):1164-1171
Alkylphenol polyethoxylates (APEOs) have been widely used as nonionic surfactants in a variety of industrial and commercial products. Typical compounds are nonylphenol polyethoxylates (NPEOs) and octylphenol polyethoxylates (OPEOs), which serve as precursors to nonylphenol (NP) and octylphenol (OP), respectively. NP and 4-t-OP are known to have endocrine disrupting effects on fish (medaka, Oryzias latipes), so it is important to know the concentrations of APEOs in the environment. Because the analytical characteristics of these compounds depend on the length of the ethoxy chain, it is necessary to use appropriate compounds as internal standards or surrogates. We synthesized two 13C-labeled surrogate compounds and used these compounds as internal standards to determine NPEOs and OPEOs by high-performance liquid chromatography (LC)-mass spectrometry. Method detection limits were 0.015 microg/L for NP (2)EO to 0.037 microg/L for NP(12)EO, and 0.011 microg/L for OP(3,6)EO to 0.024 microg/L for OP (4)EO. NPEO concentrations in water from a sewage treatment plant were less than 0.05-0.52 microg/L for final effluent and 1.2-15 microg/L for influent. OPEO concentrations were less than 0.05-0.15 microg/L for the final effluent and less than 0.05-1.1 microg/L for influent. 相似文献
74.
75.
Yonezo Suzuki 《Die Naturwissenschaften》1964,51(23):555-556
76.
77.
Potential synergistic interactions between polycyclic aromatic hydrocarbons in a household sewage sludge compost extract were investigated using the Dioxin-Responsive Chemical-Activated Luciferase gene eXpression (DR-CALUX) assay and reverse-phase high-performance liquid chromatography (RP-HPLC) fractionation. The biological activity of the crude extract was measured in vitro using the CALUX assay. The CALUX activity of the extract was as potent as 360-pg CALUX-TEQ (2,3,7,8-TCDD equivalent value) per g sample, this was 70 times above the WHO-TEQ value which was derived from chemical analyses of dioxins/furans and dioxin-like PCBs of the mixture. The CALUX activity pattern of the crude extract and the retention times of 26 polycyclic aromatic compounds (PACs), as determined by RP-HPLC on an octadecylsilica column, suggested that the dioxin-like compounds with the log K(OW) (n-octanol/water partition coefficient) values corresponding to 6.0-7.0 contributed highly to the whole activity. The CALUX activity of the crude extract was three times the sum of the CALUX activities of the RP-HPLC separated fractions. Mixture effects were assessed by co-exposure of each HPLC fraction and 2,3,7,8-TCDD to the cells. The four concentration levels of added 2,3,7,8-TCDD corresponded to the TEQ value in the original compost sample. The experimental CALUX activity was higher than the predicted CALUX activity for some fractions. It was demonstrated that some compounds in the compost sample interacted synergistically with 2,3,7,8-TCDD in terms of dioxin-like activity. This finding points out the necessity for detailed investigation of synergistic effects in environmental samples. 相似文献
78.
Photoperiodic time measurement is a well-documented adaptation of multicellular plants and animals to seasonal changes in the environment, but it is unclear whether unicellular organisms can exhibit bona fide photoperiodic responses. We demonstrate that the occurrence of zygospore germination of the unicellular alga Chlamydomonas is a genuine photoperiodic response. Germination efficiency is enhanced in long days as compared with short days. While the total amount of light exposure influences the efficiency of germination, the photoperiod is a significant cue for germination. The developmental stage that senses the photoperiod is just prior to mating and during the first days of zygospore development, so there may be a critical window of zygospore maturation that is regulated by photoperiod. Because zygospores are resistant to freezing injury, whereas vegetative cells are not, it is likely that the suppression of germination by short days is an adaptive response for overwintering of Chlamydomonas. Therefore, Chlamydomonas is a single-celled organism that is capable of photoperiodic responses. 相似文献
79.
18S rRNA phylogeny of sea spiders with emphasis on the position of Rhynchothoracidae 总被引:2,自引:1,他引:1
Koichiro?Nakamura Yasunori?KanoEmail author Nobuo?Suzuki Takashi?Namatame Akinori?Kosaku 《Marine Biology》2007,153(2):213-223
The phylogenetic relationships among all living families of sea spiders (Arthropoda: Pycnogonida) are investigated using nearly
complete 18S rRNA sequences from 57 ingroup species and five chelicerates under the Bayesian and maximum likelihood methods.
Monophyly of Colossendeidae, Pycnogonidae, Phoxichilidiidae, Endeidae and Pallenopsidae is consistently supported. However,
the genera formerly classified in the family Ammotheidae are split up into two distantly related groups. The genera Ascorhynchus and Eurycyde (here recognized as Ascorhynchidae) are possibly an early offshoot of sea spiders, whereas other ammotheids constitute a
robust terminal clade with Pallenopsidae, Phoxichilidiidae and Endeidae. This topology also opposes the prevalent assumption
of successive losses and simplification of three kinds of cephalic appendages like in a previous cladistic analysis. At least
three independent losses are suggested for palps by the inferred topology, and both chelifores and female ovigers may have
been lost twice. Our knowledge of early ontogeny and internal anatomy is more congruent with the present 18S rRNA data. The
families Callipallenidae and Nymphonidae with unique “attaching larvae” are grouped together in present molecular trees, suggesting
that extended paternal care of offspring evolved only once in Pycnogonida. Confident clustering of Pycnogonidae and Rhynchothoracidae
indicates that the number of female genital pores is an evolutionary conservative character. 相似文献
80.
Johannes Breit Satoru Komatsu Shinji Kaneko Partha Pratim Ghosh 《Environment, Development and Sustainability》2016,18(1):73-94
This paper investigates household preferences regarding an improved supply of electricity in rural Bangladesh, where the expansion of stable electricity is an urgent policy issue. The paper examines household preferences regarding reductions in the frequency and duration of power outages. It also examines prior notification mechanisms that do not necessarily provide an increased supply of electricity but that allow households to prepare for potential power failures. A questionnaire survey designed as a choice experiment was applied to households to elicit preferences. The econometric analysis reveals that villagers prefer a reduction in both the frequency and duration of power outages and a 1-day prior notification of power outages. There are slight disparities in preferences according to the season and the timing of improvements (e.g., summer or winter and all day or peak hours). Thus, the present study may be beneficial for policymakers when considering the provision of electricity supply improvements in rural areas in exchange for slight increases in electricity tariffs. 相似文献