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1.
Identification of reactive oxygen species (ROS) that contribute to bisphenol-A (BPA) degradation and monitoring of BPA at various concentrations in human serum under Fenton reaction conditions were carried out using electron spin resonance (ESR) spectrophotometry and high performance liquid chromatography with electrochemical detection (HPLC-ECD). BPA recovery decreased with increasing Fe concentration and time, both with a Fenton reaction using Fe(II), and with a Fenton-like reaction using Fe(III). In these reactions, BPA dose-dependently decreased the intensity of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO)-*OH, up to 1 microg/ml BPA, and no change in DMPO-O(2)(?-) intensity was observed. The decrease in BPA recovery was inhibited strongly by addition of serum under Fenton-like reaction conditions, and there was a negative correlation between turbidity and BPA recovery. To clarify the mechanism by which serum inhibits BPA degradation, the relationship between BPA recovery and sample turbidity, and characteristics of the precipitates were investigated using spectrophotometry and X-ray analysis. The precipitate formed in the serum-containing sample consisted of C, S, O, P and Fe. BPA degradation was also inhibited under Fenton-like reaction conditions in phosphate buffered saline (PBS), and a precipitate consisting of O, P, and Fe appeared. Precipitates also appeared in authentic albumin and gamma-globulin when sulfate was added with Fenton reagents. After precipitate removal, both Fe and protein concentrations in the supernatant of the protein solutions with sulfate decreased with increasing Fe addition. We demonstrate here that hydroxyl radical generation from Fenton or Fenton-like reactions can degrade BPA, and that serum strongly inhibits BPA degradation, not only by competing with BPA for hydroxyl radicals, but also by trapping Fe with oxidative components present in the serum. 相似文献
2.
N. Aizawa 《Marine Biology》1998,131(3):523-532
In several species of ocypodid crabs, including Ilyoplax pusilla (De Haan), waving displays tend to be synchronized among neighboring individuals. However, no quantitative study has yet
been conducted. In this study, responses of I. pusilla males to waving of video and real crabs were examined. Spontaneous, periodic waving was observed even when no stimulus waves
were present. When single isolated waves of the video crab were randomly delivered (single pulse perturbation), crabs waved
either immediately after the stimuli or after some time had elapsed. Assuming that waves immediately after the stimuli were
triggered prior to those stimuli, crabs typically responded after a roughly constant delay from the onset of each stimulus.
The delay (response time) was close to, but slightly shorter than, the spontaneous wave period. Dependency of response time
upon timing of the stimulus (stimulus time) was at most weak. Responses of crabs to periodic waves of the video crabs and
waves of␣the real crabs were basically consistent with the results of single pulse perturbation, although there was a consistent
tendency for stimulus time and response time to be negatively correlated near stimulus time = 0 s. Overall, these results
demonstrate that males of I. pusilla adjust signal timing relative to a neighbor in a manner of phase delay synchrony. The similar response pattern has also been
noted in synchronous flashing of fireflies and the calling of katydids. Moreover, these experiments with I.␣pusilla demonstrate the value of video playback as a research tool in this species.
Received: 4 April 1997 / Accepted: 17 December 1997 相似文献
3.
Kosuke Toshiki Pham Quy Giang Kevin Roy B.Serrona Takahiro Sekikawa Jeoung-soo Yu Baasandash Choijil Shoichi Kunikane 《环境科学学报(英文版)》2015,28(2):178-186
Currently, most developing countries have not set up municipal solid waste management systems with a view of recovering energy from waste or reducing greenhouse gas emissions. In this article, we have studied the possible effects of introducing three energy recovery processes either as a single or combination approach, refuse derived fuel production,incineration and waste power generation, and methane gas recovery from landfill and power generation in Ulaanbaatar, Mongolia, as a case study. We concluded that incineration process is the most suitable as first introduction of energy recovery. To operate it efficiently,3Rs strategies need to be promoted. And then, RDF production which is made of waste papers and plastics in high level of sorting may be considered as the second step of energy recovery.However, safety control and marketability of RDF will be required at that moment. 相似文献
4.
Kosuke Toshiki Pham Quy Giang Kevin Roy B. Serrona Takahiro Sekikawa Jeoung-soo Yu Baasandash Choijil Shoichi Kunikane 《环境科学学报(英文版)》2015
Currently, most developing countries have not set up municipal solid waste management systems with a view of recovering energy from waste or reducing greenhouse gas emissions. In this article, we have studied the possible effects of introducing three energy recovery processes either as a single or combination approach, refuse derived fuel production, incineration and waste power generation, and methane gas recovery from landfill and power generation in Ulaanbaatar, Mongolia, as a case study. We concluded that incineration process is the most suitable as first introduction of energy recovery. To operate it efficiently, 3Rs strategies need to be promoted. And then, RDF production which is made of waste papers and plastics in high level of sorting may be considered as the second step of energy recovery. However, safety control and marketability of RDF will be required at that moment. 相似文献
5.
Yoshiro Ono Hidehito Uemura Yoshinori Kanjo Osami Kawara Toshiki Ayano 《Journal of Material Cycles and Waste Management》2000,2(1):38-42
Construction waste such as road pavement and concrete is estimated to constitute about 50% of the total industrial waste in
Japan, and the recycling of such material has recently become a prominent topic among construction engineers. It has also
been suggested that various types of industrial waste be utilized as components of construction materials. This paper investigates
the environmental safety of certain materials in terms of the elutions and genotoxicities of these substances. The substances
extracted from some materials, such as emulsifier, ash, and sediment, were found to have genotoxic characteristics. The dose-related
responses of the various materials and their genotoxic strengths are shown.
Received: June 16, 1998 / Accepted: September 7, 1999 相似文献
6.
So Kazama Toshiki Aizawa Toru Watanabe Priyantha Ranjan Luminda Gunawardhana Ayako Amano 《Sustainability Science》2012,7(1):45-54
Flooding and inundation are annual events that occur during the rainy season in Cambodia, and inundation has a strong relationship
with human health. This study simulated the coliform bacteria distribution using a hydraulic model and estimated the impact
of inundation on public health using a dose–response model. The model parameters were calibrated using field survey data from
Cambodia and obtained good agreement with the coliform group count distribution. The results suggest that the impact of inundation
on human health is most noticeable in residential areas. The annual average risk of infection during medium-sized flood events
is 0.21. The risk due to groundwater use ranges from 0.12 to 0.17 in inundation areas and reaches as high as 0.23 outside
the inundation areas. The risk attributed to groundwater use is therefore higher than that for surface water use (0.02–0.06),
except in densely populated areas at the city center. There is a high risk for infection with waterborne disease in residential
areas, and the annual average risk during small flood events is 0.94. An assessment of possible countermeasures to reduce
the risk shows that the control of inundation may bring more risk to public health in Cambodia. Shallower inundation water
(<0.3 m) leads to a higher risk of infection, but if the depth is greater than 2 m, the risk is low in residential areas.
The simulated results explain the spatial distributions of infection risk,, which are vitally important for determining the
highest priority places with relatively high risk and will be helpful for decision makers when considering the implementation
of countermeasures. 相似文献
7.
Yusaku?SakataEmail author Thallada?Bhaskar Md. Azhar?Uddin Akinori?Muto Toshiki?Matsui 《Journal of Material Cycles and Waste Management》2003,5(2):113-124
Dehalogenation is a key technology in the feedstock recycling of mixed halogenated waste plastics. In this study, two different methods were used to clarify the effectiveness of our proposed catalytic dehalogenation process using various carbon composites of iron oxides and calcium carbonate as the catalyst/sorbent. The first approach (a two-step process) was to develop a process for the thermal degradation of mixed halogenated waste plastics, and also develop dehalogenation catalysts for the catalytic dehydrochlorination of organic chlorine compounds from mixed plastic-derived oil containing polyvinyl chloride (PVC) using a fixed-bed flow-type reactor. The second approach (a single-step process) was the simultaneous degradation and dehalogenation of chlorinated (PVC) and brominated (plastic containing brominated flame retardant, HIPS–Br) mixed plastics into halogen-free liquid products. We report on a catalytic dehalogenation process for the chlorinated and brominated organic compounds formed by the pyrolysis of PVC and brominated flame retardant (HIPS–Br) mixed waste plastics [(polyethylene (PE), polypropylene (PP), and polystyrene (PS)], and also other plastics. During dehydrohalogenation, the iron- and calcium-based catalysts were transformed into their corresponding halides, which are also very active in the dehydrohalogenation of organic halogenated compounds. The halogen-free plastic-derived oil (PDO) can be used as a fuel oil or feedstock in refineries. 相似文献
8.
Hideto Yoshida Kazuyuki Shimamura Hirofumi Aizawa 《Journal of Material Cycles and Waste Management》2007,9(2):101-111
Focusing on the promotion of the “3Rs” – reduce, reuse, and recycle – the authors summarize the policy that Japan has evolved
in waste management and recycling policy over the years. To realize an international sound material-cycle society (SMS), the
3R approaches should first be implemented in each individual country. After each country has established an SMS to the best
of its ability, contribution toward reducing the environmental load internationally, especially across all of East Asia, will
be achieved by having waste and recyclable resources that cannot be handled in one country effectively used or processed in
other countries. The current situation of international resource circulation is described and a concept of SMS at an international
level is proposed.
The views expressed herein are those of the authors and are not necessarily the official views of the organizations with which
the authors are affiliated. 相似文献
9.
Shin-ichi Sakai Yasuhiro Hirai Hirofumi Aizawa Shizuko Ota Yasuhiro Muroishi 《Journal of Material Cycles and Waste Management》2006,8(1):56-62
Atmospheric emissions of deca-brominated diphenyl ether (DBDE) in Japan were estimated based on the material flow of DBDE
products and their emission factors. In 2002, the demand for DBDE in Japan was 2200 ton/year and the stock level was about
60 000 ton. The DBDE flow into the waste stream was estimated to be about 6000 ton/year and the flow out through second-hand
product exports was more than 700 ton/year. Home appliance recycling facilities dismantle and crush domestic wastes containing
about 600 ton of DBDE annually. Material recycling of crushed plastics is not commonly practiced as yet. Emission factors
from plastics processing (2 × 10−9–1 × 10−7), textile processing (9 × 10−7), home appliance recycling (8 × 10−9–5 × 10−6), and waste incineration (1 × 10−7–2 × 10−6) were estimated using field measurement data. The DBDE emission rate through house dust during the service life of final
products (2 × 10−7–9 × 10−7 per year) was estimated using the DBDE concentration in dust and the amount of dust in used televisions. Emission factors
from previous studies were also used. The estimated total DBDE emission was 170–1800 kg/year. These results suggest the necessity
of characterizing emissions during the service life of products, which is essential information for formulating an appropriate
e-waste recycling strategy. 相似文献
10.
Masanobu Mori Tsuyoshi Sugita Akinori Mase Takahiro Funatogawa Masaru Kikuchi Kazuhiko Aizawa Shigekazu Kato Yoichi Saito Tsukasa Ito Hideyuki Itabashi 《Chemosphere》2013,90(4):1359-1365
This paper reports on the photodecomposition of aqueous humic acid (HA) by a TiO2-coated ceramic foam filter (TCF) reactor and on the potential for the formation of disinfection byproducts (DBPs) upon chlorination of the photocatalytically treated solutions. This photocatalytic reactor can also be applied to the removal of natural organic matter (NOM) in swamp waters. The proposed photocatalytic reaction system was operated as per standardized methodologies. First, the ability of the TCF to decompose HA (a representative compound of NOM) was evaluated from the changes in the total organic carbon (TOC) and UV254 with the reaction time. Remarkably, TOC removal and UV254 values ranging from 44% to 61% and from 60% to 83%, respectively, were achieved. The potential for the formation of DBPs (total trihalomethane and total haloacetic acid) by chlorination of the phototreated solution was strongly dependent on the TOC removal and UV254 values in the solution. The degree of photodecomposition of NOMs in the swamp water samples and the DBP formation potential showed similar trends as in the case of the standard solutions containing HA. The method used in this study could be effectively used to evaluate the efficiency of TCF for reducing HA and NOM, while suppressing the formation of DBP products. 相似文献