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41.
Koichi Haraguchi Akio Koizumi Kayoko Inoue Kouji H. Harada Toshiaki Hitomi Mutsuko Minata Miyako Tanabe Yoshihisa Kato Eri Nishimura Yoshiaki Yamamoto Takao Watanabe Katsunobu Takenaka Shigeki Uehara Hye-Ran Yang Min-Young Kim Chan-Seok Moon Hae-Sook Kim Peiyu Wang Aiping Liu Nguyen Ngoc Hung 《Environment international》2009,35(7):1072-1079
Human breast milk samples collected in 2007–2008 from four countries, Vietnam (Hanoi), China (Beijing), Korea (Seoul) and Japan (Sendai, Kyoto and Takayama), were analyzed for persistent organic pollutants (POPs) such as dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordane-related compounds (CHLs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Comparing with previous surveys, the present study indicates that the DDTs in breast milk from China and Vietnam had gradually decreased during the last decade, but were still 5–10 times higher than those in other nations. The ratios of p,p′-DDE/p,p′-DDT and o,p′-DDT/p,p′-DDT were higher in Beijing than in the other countries, suggesting that there is less fresh intake of commercial DDT products and a possible exposure to dicofol in China. CHL and PCB levels were relatively higher in mothers from Japan, whereas β-HCH and HCB were more common in Chinese women. In Japan, it is suspected that mothers in the urban/coastal area (Sendai) were more continuously exposed to organochlorine pesticides (OCPs) than mothers in the rural/inland area (Takayama). In addition, OCP levels in primiparae were significantly higher than those in multiparae from Japan and Korea. These indicate that both parity and regional factors are major determinants of the levels of OCPs and PCBs in human milk. On the other hand, higher concentrations of PBDEs were observed in mothers' milk from Korea. The congener was dominated by BDE-47 (43–54%), followed by BDE-153 (23–33%) in all regions except for Beijing where BDE-28 (23%) was relatively abundant. In Japanese breast milk, regional and parity-dependent distributions were not observed for PBDEs. Among PBDE congeners, age-dependency was observed for BDE-153, which was negatively correlated (p < 0.05) to the age of mothers in Kyoto (17 participants were housewives), while it increased with age in Sendai (10 participants were clerks). No such correlation was seen for BDE-47, indicating that BDE-47 was ingested and assimilated via different kinetics or routes from BDE-153 in Japan. 相似文献
42.
In this study, potassium iodide (KI) was found to be capable of reducing selenium(VI) to selenium(IV). When KI was added to
Se(VI) solution, the Se(VI) concentration rapidly decreased with an increase in the KI/Se(VI) molar ratio. By using the potential-pH
equilibrium diagram for the selenium/water system, we confirmed that Se(VI) reduced to Se(IV) because the potential of the
solution shifted to the stable Se(IV) region upon the addition of KI. This reduction accompanies the oxidation of I− to I3−. The reduction of Se(VI) by KI was found to be effective for concentrated Se(VI) solutions. 相似文献
43.
Guido Grause Tomoyuki Mochizuki Tomohito Kameda Toshiaki Yoshioka 《Journal of Material Cycles and Waste Management》2013,15(2):122-128
Fiber-reinforced plastic sheets containing unsaturated polyester cross-linked with styrene, CaCO3 and glass fibers as fillers were pyrolyzed in a helium and steam atmosphere in order to recover glass fibers and valuable organic pyrolysis products. Glass fibers were separated from CaCO3 and CaO by dissolving calcium salts in hydrochloric acid. Residual organic material was burnt afterwards. Best results were obtained at a pyrolysis temperature of 600 and 700 °C, resulting in a large liquid fraction high in styrene, leaving little residual organic material on the surface of the glass fibers. At a pyrolysis temperature of 500 °C, the degradation of the polymer matrix was incomplete, and at 900 °C, glass fibers were destroyed in the presence of CaO, leaving CaSiO3 as a product. 相似文献
44.
James H. Turner Phil A. Lawless Toshiaki Yamamoto David W. Coy Gary P. Greiner John D. McKenna 《Journal of the Air & Waste Management Association (1995)》2013,63(5):715-726
This is the second of a two-part article that reviews electrostatic precipitation theory, presents size estimating methods, and gives costing procedures for a variety of electrostatic precipitator (ESP) types and sizes. Part I of the article, which appeared in the April 1988 issue of JAPCA, discussed theory and sizing; this part presents costing. Information is given for estimating total capital investment including separate costs for the bare ESP (five types) and auxiliaries. Factors are given for installation and for indirect costs. Direct and indirect annual costs are discussed. An example problem is given. 相似文献
45.
Junya Katagiri Siqingaowa Borjigin Toshiaki Yoshioka Tadaaki Mizoguchi 《Journal of Material Cycles and Waste Management》2010,12(2):136-146
The formation and decomposition of tetrafluoroborate ions (BF4−) in H3BO3-Al3+-F− solutions were investigated via experiments and thermodynamic calculations. The concentration of the formed BF4− increased with decreasing pH, raising the total fluoride concentration and lowering the total aluminum ion concentration.
Once formed, BF4− was stable under neutral and alkaline conditions. Fluoride in the form of BF4− was converted to fluoroaluminate ions by adding an aluminum compound under acidic conditions. A method for removing fluoride
in the form of BF4− is proposed whereby fluoroaluminate ions formed by the reaction of BF4− with aluminum are decomposed with calcium ions. This process was applied to the treatment of wastewater from flue gas desulfurization
plants, and resulted in a satisfying level of reduction in the range of the fluoride emission limit of 8 mg/l. 相似文献
46.
Misuzu Asari Shin-ichi Sakai Toshiaki Yoshioka Yasumasa Tojo Tomohiro Tasaki Hidetaka Takigami Kohei Watanabe 《Journal of Material Cycles and Waste Management》2013,15(3):290-299
Shortly after the March 11th earthquake and tsunami in eastern Japan, a Task Team for Disaster Waste Management and Reconstruction was established within the Japan Society of Material Cycles and Waste Management (JSMCWM). One of the major tasks undertaken by the team was to create a manual entitled, Strategies for Separation and Treatment of Disaster Waste. In this paper, this JSMCWM manual is introduced, followed by a review of existing guidelines for disaster waste management in various countries. We identify useful guidelines created by international agencies, national and local governments. The JSMCWM manual adds our new experiences, especially characterized by a huge scale of disaster and tsunami information, to the existing knowledge with an emphasis on separation and subsequent treatment options. It should be desirable to share our knowledge and experiences, not only domestically but also with other countries in the world, especially regions that could be affected by large earthquake and tsunami events. 相似文献
47.
Aihua Zhang Toshiaki Yamamoto 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1442-1448
ABSTRACT Nonthermal plasma chemical decomposition of bromomethane (CH3Br) was investigated with a coaxial type packed-bed plasma reactor. It has been demonstrated that plasma chemical processing is an effective approach to decompose CH3Br in a wide concentration range. It has been shown that CH3Br decomposition reactivity depends on reactor operating factors such as background gas, O2 concentration, and humidification. Higher decomposition efficiencies can be obtained in dry N2. However, organic byproducts such as BrCN are concurrently produced under deaerated conditions. Water suppresses CH3Br decomposition and also affects the yields of COx (CO and CO2) and organic byproducts due to the involvement of some active species generated from water. The presence of O2 retards CH3Br decomposition by quenching high-energy electrons, while it suppresses organic byproducts and improves COx yield. The reacted carbons in CH3Br are recovered as COx almost quantitatively in air. Higher CO2 selectivities cannot be achieved by increasing O2 concentration. NOx formation, which is accompanied by CH3Br decomposition, can be effectively suppressed by decreasing O2 concentration down to 2%. Furthermore, reaction mechanisms are discussed by comparing the reactivities of CH3Br and its congeners. 相似文献
48.
Shigetaka Seki Yoichi Yamashita Hiroshi Kamikawaji Alfons Buekens Toshiaki Yoshioka 《Journal of Material Cycles and Waste Management》2018,20(4):2068-2076
It is of huge importance for sustainability to find a pragmatic solution for recycling of a variety of wastes emitted in small mass such as the case of wallpaper replacements. A combination of two-step sorting scheme and transportation of the wastes in collaboration with the wholesalers was proposed to enhance the efficiency of recycling. The two-step sorting consists of the first sorting at the wallpaper hanging sites to separate and group wastes in a way to avoid heavy additional burden on the hanging job. Secondary sorting is conducted at a Sorting Center to re-group wastes to send to an intermediate processing company for recycling. To minimize the costs for transportation, the grouped wastes emitted at the hanging sites are brought back by the hangers and kept temporally and then moved to the wholesaler(s) on the way to receive new materials. When the wastes at the wholesaler(s) become sufficiently large for economic transportation, a truck is arranged to collect the wastes to transport them to the Sorting Center. A feasibility study to test the practicality of the method confirmed that it could be operable and the cost would be comparable or lower than that currently incurred for disposal of the wastes. 相似文献
49.
Pyrolysis of tetrabromobisphenol-A containing paper laminated printed circuit boards 总被引:2,自引:0,他引:2
Tetrabromobisphenol-A (TBBA) is the most common brominated fire retardant. In this study, a TBBA containing paper laminated printed circuit board (PCB) prepared from novolac was pyrolysed by both TGA and in a quartz glass reactor between 40 and 1,000 degrees C. The products were online detected by MS. It was found that the PCB degraded in three steps. Step one (<270 degrees C) consisted of the evolution of water and CO(2) from the paper laminate. In the second step, between 270 and 370 degrees C, the fire retardant decomposed, releasing HBr and brominated aromatics. In the third step, at temperatures above 370 degrees C, the phenol resin decomposed and char was formed. Compared to pure TBBA, which mainly produces brominated phenols, the brominated products enclosed in the char released HBr during the last degradation step as well as during the second step. Most of the bromine left the resin in the form of HBr, with about 14% of the bromine being fixed in brominated aromatics and less than 2% remaining in the residue. 相似文献
50.
Toshiaki Yoshida 《毒物与环境化学》2013,95(9):1789-1804
The major metabolites in urine of rats administered the fluorine-containing pyrethroids transfluthrin, profluthrin, and metofluthrin, which are used widely recently as mosquito repellents or mothproof repellents, were identified to establish biological indexes for evaluating the absorption amounts of these pyrethroids in the general population. A single dose of 300?mg?kg?1 body weight of each pyrethroid was separately administered intraperitoneally to male Sprague-Dawley rats and urine samples were collected until 24 hours after the administration. The metabolites identified by gas chromatography-mass spectrometry were as follows: 2,3,5,6-tetrafluorobenzyl alcohol, 2,3,5,6-tetrafluorobenzoic acid, and 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (DCCA) for transfluthrin; 4-methyl-2,3,5,6-tetrafluorobenzyl alcohol, 4-methyl-2,3,5,6-tetrafluorobenzoic acid, 4-hydroxymethyl-2,3,5,6-tetrafluorobenzyl alcohol (HOCH2–FB–Al), and 2,2-dimethyl-3-(1-propenyl)-cyclopropanecarboxylic acid (MCA) for profluthrin; 4-methoxymethyl-2,3,5,6-tetrafluorobenzyl alcohol, HOCH2–FB–Al and MCA for metofluthrin. In addition, several compounds estimated to be metabolites were detected as follows: hydroxylated DCCA and its lactone for transfluthrin; 4-hydroxymethyl-2,3,5,6-tetrafluorobenzoic acid (HOCH2–FB–Ac), hydroxylated MCA and its lactone for profluthrin; 4-methoxymethyl-2,3,5,6-tetrafluorobenzoic acid, HOCH2–FB–Ac, hydroxylated MCA, and its lactone for metofluthrin. The pyrethroids administered underwent metabolic reactions such as ester hydrolysis and oxidation, and most of the metabolites were excreted as their conjugates into urine. These findings should be useful as basic data for evaluating the health effects of exposure to pyrethroids for the general population. 相似文献