排序方式: 共有24条查询结果,搜索用时 15 毫秒
11.
12.
Seiichi Ishikawa Naoko Ueda Yuji Okumura Yoshikazu Iida Kenzo Baba 《Journal of Material Cycles and Waste Management》2007,9(2):167-172
Spent coagulant in water supply plant sludge was extracted with H2SO4 and the efficiency of the reused coagulant was studied. The optimum pH values for coagulant extraction and clarification
with the reused coagulant were 3.0–4.0 and about 6, respectively. In treating raw influent obtained from a sewage treatment
plant and wastewater from a coastal landfill site, the removal of chemical oxygen demand (COD), total nitrogen, and total
phosphorous with the recovered coagulant was higher than that with commercial aluminum sulfate or polyaluminum chloride. In
addition, the sludge settling properties, the extra sludge mass formation, the supernatant quality, and the cost of reagents
were also studied. The coagulant recovered from water supply plant sludge by H2SO4 extraction could be successfully reused for the clarification of domestic and food industry wastewaters. 相似文献
13.
The procedure for modelling the growth of single-species populations [Sakanoue, S., 2007. Extended logistic model for growth of single-species populations. Ecol. Model. 205, 159–168] is improved to be applicable to the study of the dynamics of interacting populations. The improved procedure is based on three assumptions: resource availability changes with population size as a variable, resource supply to populations and population demand for resources are defined as functions of resource availability and population size, and the variables of resource availability and population size shift in the supply function attracted to the demand function. These assumptions are organized into three equations. The equations can generate the dynamics models of plant, herbivore, and detritivore populations, and their own resources. The models can be used to describe prey–predator dynamics. They naturally contain nonlinear terms for the predator’s numerical and functional responses. Depending on the terms, the fluctuations in resource availability and population size stabilize. The three equations can also generate the dynamics models of different populations consuming the same resources. The analysis of zero isoclines of the models shows that a superior population can be simply defined as one with a higher intrinsic rate of natural increase, that a stable coexistence may be realized with the intraspecific interference or the interspecific facilitation of superiors, and that the interspecific interference or the intraspecific facilitation of inferiors may make the coexistence unstable and the inferiors winners depending on their initial population size. 相似文献
14.
Yasukatsu Maeda Atsuyoshi Nakayama Norioki Kawasaki Kazuko Hayashi Seiichi Aiba Noboru Yamamoto 《Journal of Polymers and the Environment》1996,4(4):225-233
Chain-extension reactions were carried out using titanium-iso-propoxide (TIP) as a catalyst for a series of polyesters or copolyesterethers with low molecular weights (M
n
=1500–10,000) synthesized by the ring-opening copolymerization of succinic anhydride (SA) with ethylene oxide (EO). The copolymers having aM
n
from 25,000 to 50,000 of different properties were obtained. Both the melting point (T
m
) and the fusion heat (H), which indicate the crystallinity of the copolymers, rose with an increase in SA content in the copolymers. Semitransparent films were prepared by compression molding of the copolymers. The biodegradation of the copolymer films was evaluated by enzymatic hydrolysis by lipases and by an aerobic gas evolution test in standard activated sludge. The hydrolyzability of these copolymers by three kinds of lipases was affected by their copolymer composition SA/EO, form, andM
n
. The copolyesterether (SA/EO=43/57,M
n
=48,900) was more easily biodegraded by standard activated sludge compared to the polyester (SA/EO=47/53,M
n
=36,300).Presented at the Pacifichem-95, December 17–22, 1995, Honolulu, Hawaii. 相似文献
15.
Seiichi Miyamoto Hinrich L. Bohn 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1051-1054
An equation derived for initial collection of efficiency E0 of a gravel bed filter predicts that — ln(1 — E0) is proportional to the thickness of the gravel layer, to the — 5/3 power of the diameter of uniform gravels, and to the — 2/3 power of the Darcy airflow velocity. The experimental data obtained from NH4CI fume removal from dry air at room temperature by sieved gravel fractions generally supported the equation, except that the effect of mean gravel size was represented by the —1.43 power of the average diameter. 相似文献
16.
Naoko Yamano Atsuyoshi Nakayama Norioki Kawasaki Noboru Yamamoto Seiichi Aiba 《Journal of Polymers and the Environment》2008,16(2):141-146
We identified a biodegrading microorganism of polyamide (nylon) 4, a linear polymer of γ-aminobutyric acid (GABA). From activated
sludge, the biodegrading bacteria strains of Pseudomonas sp. were isolated and identified by their taxonomic characteristics and nucleotide sequences of 16S rDNA. One strain, ND-11,
was grown on a minimal medium containing polyamide 4 (PA4) as the sole carbon source. The strain produced GABA as a degradation
intermediate, as identified by analyzing the NMR spectra of degraded products. The culture supernatant of strain ND-11 degraded
the emulsified PA4 completely within one day. These results suggest that the ND-11 strain degraded PA4 using its extracellular
enzymes to hydrolyze amide bonds. 相似文献
17.
Fluxes of carbon dioxide, methane and nitrous oxide in two contrastive fringing zones of coastal lagoon, Lake Nakaumi, Japan 总被引:9,自引:0,他引:9
We measured fluxes of carbon dioxide (CO(2)), methane (CH(4)), and nitrous oxide (N(2)O) simultaneously in two typical fringing zones, sandy shore and salt marsh, of coastal lagoon, Lake Nakaumi, Japan, in mid-summer 2003. Our aim was to quantify net the greenhouse gases (GHGs) fluxes and examine key factors, which control variation of the GHGs fluxes in the two sites. Net CO(2) and CH(4) fluxes were markedly different between the two sites; magnitudes and variations of the both fluxes in sandy shore were lower than those of salt marsh. Meanwhile, magnitude and variation of net N(2)O flux in the two sites were similar. In sandy shore, temporal and spatial variation of the three GHGs fluxes were highly controlled by water level fluctuation derived from astronomic tide. In salt marsh, spatial variation of the three GHGs fluxes were correlated with aboveground biomass, and temporal variation of CO(2) and CH(4) fluxes were correlated with soil temperature. The sum of global warming potential, which was roughly estimated using the observed GHGs fluxes, was ca. 174-fold higher in salt marsh than in sandy shore. 相似文献
18.
In order to quantify the sources of chemical pollutants in the leachate from reclaimed wastes, chemical substances in 11 different types of industrial wastes were identified. Their elution behaviors were also investigated. Alkanes (5.3-890 ng g(-1)), benzenes (8.1-110 ng g(-1)), polyaromatic hydrocarbons (PAHs) (3.2-560 ng g(-1)), alcohols, steroids, phenol (7.1 ng g(-1)), ketones, furans (190-210 ng g(-1)), phthalates (8.9-560 ng g(-1)), benzoquinones, dibenzothiophene (190 ng g(-1)), benthiocarb (4.2 ng g(-1)), sulfur, nitrile compounds, amino compounds, amido compounds, pyridines, quinolines (1.8-15 ng g(-1)), isoquinolines, carbazoles, acridines, chlordenes (1.5-1.6 ng g(-1)) and nonachlors (1.1-1.6 ng g(-1)) were detected in 9 types of industrial wastes. The chemical substances detected in waste at the highest concentrations were alkanes, PAHs and phthalates. Water supply sludge, dust and brick garbage contained many kinds of chemical substances. The elution behaviors of specific chemical substances, COD and nutrients varied by characteristic and production process of each waste. Over 100 different compounds were detected in pyrolysis products including carbohydrate, carotynoid, amino acids, proteins, humic acids, lignin and combustion products. 相似文献
19.
Shu Saeki Junya Kano Fumio Saito Kaoru Shimme Seiichi Masuda Tsuyoshi Inoue 《Journal of Material Cycles and Waste Management》2001,3(1):20-23
Polyvinyl chloride (–CH2–CHCl–)
n
(PVC) was ground with a powdered inorganic material (CaO, CaCO3, SiO2, Al2O3, or slag) in a planetary ball mill under atmospheric conditions to investigate the effect of additions on its dechlorination.
The grinding causes a dehydrochlorinating reaction, forming a mixture of partially dechlorinated PVC and inorganic chloride,
depending on the grinding time. The dechlorination increases as the grinding progresses, and is improved with increasing amounts
of additives. The most effective additive is a mixture of CaO, SiO2, and Al2O3, which has the same constituent components as blast furnace slag. CaO, a mixture of CaO, SiO2, and blast furnace slag, are also effective, but CaCO3 is the least effective additive tired.
Received: August 3, 2000 / Accepted: September 21, 2000 相似文献
20.
Andriamanohiarisoamanana Fetra J. Sakamoto Yushi Yamashiro Takaki Yasui Seiichi Iwasaki Masahiro Ihara Ikko Nishida Takehiro Umetsu Kazutaka 《Journal of Material Cycles and Waste Management》2017,19(3):1253-1260
Journal of Material Cycles and Waste Management - The influence of temperature and storage time on hydrogen sulphide (H2S) emissions from two different dairy manures was investigated over four... 相似文献