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11.
Rizkianto Febrian Oshita Kazuyuki Takaoka Masaki 《Journal of Material Cycles and Waste Management》2022,24(5):1982-1990
Journal of Material Cycles and Waste Management - Wastewater treatment plants (WWTPs) are producing and treating ever-larger quantities of sewage sludge as urban populations increase in size.... 相似文献
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Kazuyuki Kudô Sumiko Tsujita Koji Tsuchida Wakana Goi Sôichi Yamane Sidnei Mateus Yosiaki Itô Shinya Miyano Ronaldo Zucchi 《Behavioral ecology and sociobiology》2005,58(1):27-35
In social-insect colonies, cooperation among nestmates is generally stabilized by their high genetic similarity. Thus, fitness gained through cooperation drops quickly as the number of reproductive females (queens) increases. In this respect, wasps of the tribe Epiponini have attracted special attention, because the colonies have tens, or even hundreds of queens. It has been empirically or genetically confirmed that relatedness within nestmates can be elevated by a mechanism known as cyclical monogyny, under which new queens are produced only after the number of old queens is reduced to one. Another likely factor that can increase relatedness within nestmates under polygyny is comb partitioning by queens. If queens concentrate their egg laying on one or a subset of the available combs, then workers may be able to rear closer relatives by focusing their work on the comb where they emerged. Using microsatellite markers, we tested the hypotheses of cyclical monogyny and comb partitioning by queens increasing relatedness within nestmates under polygyny in the large-colony epiponine wasp, Polybia paulista. There were no significant differences between relatedness within combs and between combs, and thus we ruled out the possibility that each queen partitions reproduction between combs. However, as cyclical monogyny predicts, a lower effective number of queens contributed to queen production than to worker production. Cyclical monogyny explained well the observed smaller effective number of queens for new queens than that for workers, but failed to explain the stable relatedness values throughout colony cycles.Communicated by L. Keller 相似文献
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为使水洗焚烧飞灰的稳定化处理进一步优化,探讨了热处理的加热过程、气氛条件等对水洗焚烧飞灰晶体成分演变的影响.同时也探讨了3种飞灰:锅炉飞灰(RFA)、CaO/Ca(OH)2和NaHCO3分别作为中和剂得到的两种飞灰(CaFA和NaFA)水洗后(RFA-II#、CaFA-II#和NaFA-II#)进行热处理比较.结果发现700℃是个转折点,从这个温度点开始3种水洗飞灰中的晶体成分发生明显变化;原位连续加热模式更容易形成固体溶液因而更适合重金属的稳定;NaFA-II#较之CaFA-II#更易于稳定重金属成分.Factsage的模拟结果与XRD结果一致,而且发现飞灰中氯化物在加热过程中首先释放的是HCl. 相似文献
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Accelerated carbonation of municipal solid waste incineration residues is effective for immobilizing heavy metals. In this study, the contribution of the physical containment by carbonation to immobilization of some heavy metals was examined by some leaching tests and SEM–EDS analysis of untreated, carbonated, and milled bottom ash after carbonation that was crushed with a mortar to a mean particle size of approximately 1 μm. The surface of carbonated bottom ash particles on SEM images seemed mostly coated, while there were uneven micro-spaces on the surface of the untreated bottom ash. Results of Japan Leaching Test No. 18 (JLT18) for soil pollution showed that milling carbonated bottom ash increased the pH and EC. The leaching concentration of each element tended to be high for untreated samples, and was decreased by carbonation. However, after the milling of carbonated samples, the leaching concentration became high again. The immobilization effect of each element was weakened by milling. The ratio of physical containment effect to immobilization effects by accelerated carbonation was calculated using the results of JLT18. The ratio for each element was as follows: Pb: 13.9–69.0 %, Cu: 12.0–49.1 %, Cr: 24.1–99.7 %, Zn: 20.0–33.3 %, and Ca: 28.9–63.4 %. 相似文献
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Ji-Hoon Jeong Masaki Takaoka Hideaki Ichiura Kazuyuki Oshita Takashi Fujimori 《Journal of Material Cycles and Waste Management》2016,18(2):215-221
The quantity of sludge produced by the paper industry in Japan in 2011 was estimated to be 27.91 million tons wet weight. This amount is the third largest among all industrial wastes. To explore ways of reusing recovered paper pulp and safely disposing of the residue, we investigated the distribution of metals in the process of recovery of pulp from two types of paper sludge using an ionic liquid. 32 and 46 % of pulp from paper sludge A and B was recovered using ionic liquid, respectively; the resultant weight reduction of the solid mass was comparable to that of incineration. There were virtually no heavy metals but aluminum in the recovered pulp, which makes its reuse viable at present. The characteristics of the metals in the residues differed according to the treatment used and properties of the paper sludge. Copper accounted for ~10 % in the ionic liquid used for recovery of pulp from the paper sludges. This suggests that [bmIm]Cl has the potential to dissolve a specific amount of copper compared to other metals. 相似文献
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Oshita K Takaoka M Nakajima Y Morisawa S Kanda H Makino H Takeda N 《Water environment research》2012,84(2):120-127
In this study, a method for removing water from biosolids that uses dimethyl ether (DME) as an extractant was considered. This study evaluates the applicability of the DME dewatering method to biosolid cakes by using a DME flow-type experimental apparatus. It was found that a high dewatering ratio is clearly achieved by increasing the liquefied DME/biosolid ratio and lowering the liquefied DME linear velocity. As the liquefied DME/biosolid ratio was increased, the carbon content in dewatered biosolid showed a slight decrease and the TOC concentration in separated liquid increased significantly. Finally, the input energy Es to remove 1 kg of water from the biosolid cake, using both the DME dewatering method and the conventional drying method was estimated. The calculation shows that Es for the DME dewatering process is approximately a third of Es for the conventional thermal drying process. 相似文献
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Takanori Hino Ryuichi Agawa Youichi Moriya Minoru Nishida Yasuhiro Tsugita Takao Araki 《Journal of Material Cycles and Waste Management》2009,11(1):42-54
Waste printed circuit boards contain valuable metals such as Au, Pd, Ag, and Cu that can be reutilized and harmful elements
such as Pb, Br, and Cr that must be removed from the viewpoint of environmental conservation. In this research, we examined
a method that separates the materials from printed circuit boards contained in discarded personal computers. After cutting
the printed circuit boards to a size of 20 × 20 mm, they were heated at 873 K under an Ar atmosphere to remove organic resins
containing elements such as C, H, and N. After heat treatment, the printed circuit boards were crushed using a planetary ball
mill and the pulverized powders were filtered. The fraction with a granularity of greater than 250 μm was separated into magnetic
and nonmagnetic materials by a magnetic field. Because the fraction with a granularity of less than 250 μm contained 39 mass%
of C, it was heated at 1273 K in an atmosphere of 95% Ar and 5% O2 to allow carbon combustion to take place, followed by metal reduction processing at the same temperature in an atmosphere
of 97% Ar and 3% H2. The basicity of the resulting powder was adjusted and the powder was heated at 1773 K under an Ar atmosphere. The proposed
method separated the slag and metal, and 80% of the valuable metals contained in printed circuit boards could be collected. 相似文献
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Spatial variability of nitrous oxide emissions and their soil-related determining factors in an agricultural field 总被引:1,自引:0,他引:1
Yanai J Sawamoto T Oe T Kusa K Yamakawa K Sakamoto K Naganawa T Inubushi K Hatano R Kosaki T 《Journal of environmental quality》2003,32(6):1965-1977
To evaluate spatial variability of nitrous oxide (N2O) emissions and to elucidate their determining factors on a field-scale basis, N2O fluxes and various soil properties were evaluated in a 100- x 100-m onion (Allium cepa L.) field. Nitrous oxide fluxes were determined by a closed chamber method from the one-hundred 10- x 10-m plots. Physical (e.g., bulk density and water content), chemical (e.g., total N and pH), and biological (e.g., microbial biomass C and N) properties were determined from surface soil samples (0-0.1 m) of each plot. Geostatistical analysis was performed to examine spatial variability of both N2O fluxes and soil properties. Multivariate analysis was also conducted to elucidate relationships between soil properties and observed fluxes. Nitrous oxide fluxes were highly variable (average 331 microg N m(-2) h(-1), CV 217%) and were log-normally distributed. Log-transformed N2O fluxes had moderate spatial dependence with a range of >75 m. High N2O fluxes were observed at sites with relatively low elevation. Multivariate analysis indicated that an organic matter factor and a pH factor of the principal component analysis were the main soil-related determining factors of log-transformed N2O fluxes. By combining multivariate analysis with geostatistics, a map of predicted N2O fluxes closely matched the spatial pattern of measured fluxes. The regression equation based on the soil properties explained 56% of the spatially structured variation of the log-transformed N2O fluxes. Site-specific management to regulate organic matter content and water status of a soil could be a promising means of reducing N2O emissions from agricultural fields. 相似文献
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