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21.
Masahiro Shimada Takahiko Iida Kensuke Kawarada Yoshifumi Chiba Toshihiro Mamoto Takayuki Okayama 《Journal of Material Cycles and Waste Management》2000,2(2):100-108
In an earlier report, we presented a method for preparing activated carbon from waste newspaper as a way to recycle used paper
for a purpose other than producing raw material for paper-making. In this article, we consider the porous structure of the
activated carbon that affects its adsorption properties for various substances. The specific surface area of activated carbon
prepared from waste newspaper was 838 m2/g, the micropore volume was 0.368 ml/g, and the mesopore volume was 0.138 ml/g, which is about the same as commercially available
activated carbon. The activated carbon prepared from waste newspaper usually has a high content of ash, which makes little
contribution to the adsorption properties. In particular, as compared with reagent-activated carbon, the quantities of mesopores
with a pore radius of 3–25 nm and macropores with a pore radius of 25–250 nm were 8 and 14 times larger, respectively. Activated
carbon prepared from waste newspaper has a well-developed porous structure, particularly in the mesopore and macropore ranges.
Received: July 12, 1999 / Accepted: March 8, 2000 相似文献
22.
Yuki Haga Motoharu Suzuki Chisato Matsumura Toshihiro Okuno Masahiro Tsurukawa Kazuo Fujimori Narayanan Kannan Roland Weber Takeshi Nakano 《Environmental science and pollution research international》2018,25(17):16446-16454
In this study, we analyzed hydroxylated polychlorinated biphenyls (OH-PCBs) in urine of both PCB transport workers and PCB researchers. A method to monitor OH-PCB in urine was developed. Urine was solid-phase extracted with 0.1% ammonia/ methanol (v/v) and glucuronic acid/sulfate conjugates and then decomposed using β-glucuronidase/arylsulfatase. After alkaline digestion/derivatization, the concentration of OH-PCBs was determined by HRGC/HRMS-SIM. In the first sampling campaign, the worker’s OH-PCB levels increased several fold after the PCB waste transportation work, indicating exposure to PCBs. The concentration of OH-PCBs in PCB transport workers’ urine (0.55~11 μg/g creatinine (Cre)) was higher than in PCB researchers’ urine (< 0.20 μg/g Cre). However, also a slight increase of OH-PCBs was observed in the researchers doing the air sampling at PCB storage area. In the second sampling, after recommended PCB exposure reduction measures had been enacted, the worker’s PCB levels did not increase during handling of PCB equipment. This suggests that applied safety measures improved the situation. Hydroxylated trichlorobiphenyls (OH-TrCBs) were identified as a major homolog of OH-PCBs in urine. Also, hydroxylated tetrachlorobiphenyls (OH-TeCBs) to hydroxylated hexachlorobiphenyls (OH-HxCBs) were detected. For the sum of ten selected major indicators, a strong correlation to total OH-PCBs were found and these can possibly be used as non-invasive biomarkers of PCB exposure in workers managing PCB capacitors and transformer oils. We suggest that monitoring of OH-PCBs in PCB management projects could be considered a non-invasive way to detect exposure. It could also be used as a tool to assess and improve PCB management. This is highly relevant considering the fact that in the next 10 years, approx. 14 million tons of PCB waste need to be managed. Also, the selected populations could be screened to assess whether exposure at work, school, or home has taken place. 相似文献
23.
Suehiro F Mochizuki H Nakamura S Iwata H Kobayashi T Tanabe S Fujimori Y Nishimura F Tuyen BC Tana TS Suzuki S 《Chemosphere》2007,68(8):1459-1464
Tributyltin (TBT) is organotin compound that is toxic to aquatic life ranging from bacteria to mammals. This study examined the concentration of TBT in sediment from and near the Mekong River and the distribution of TBT-resistant bacteria. TBT concentrations ranged from <2.4 to 2.4 ng/g (dry wt) in river sediment and <2.4-15 ng g(-1) (dry wt) in harbor sediment. Viable count of total bacteria ranged from 2.0 x 10(4) to 1.4 x 10(7)cfu/g, and counts of TBT-resistant bacteria ranged <1.0 x 10(2) to 2.5 x 10(4)cfu/g. The estimated occurrence rate of TBT-resistant bacteria ranged from <0.01 to 34% and was highest in upstream sites in Cambodia. The occurrences of TBT in the sediment and of TBT-resistant bacteria were unrelated, and chemicals other than TBT might induce TBT resistance. TBT-resistant bacteria were more abundant in the dry season than in the rainy season. Differences in the selection process of TBT-resistant bacteria between dry and rainy seasons were examined using an advection-diffusion model of a suspended solid (SS) that conveys chemicals. The estimated dilution-diffusion time over a distance of 120 km downstream from a release site was 20 days during dry season and 5 days during rainy season, suggesting that bacteria at the sediment surface could be exposed to SS for longer periods during dry season. 相似文献
24.
Miyamoto Shintaro Hayashi Kensuke Naruse Daiki Hosokawa Yoshifumi Minagawa Hiroshi Hisada Makoto 《Journal of Material Cycles and Waste Management》2022,24(4):1396-1406
Journal of Material Cycles and Waste Management - Although fly ash, as used for supplementary cementitious material in Portland cement concrete, can reduce the heat of hydration and suppress the... 相似文献