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1.
The mathematical formulations in a one-dimensional compartment model of the biodegradation of organic landfill components are described. The model is designed to switch between anaerobic and aerobic conditions, depending on the local oxygen concentration. The model also includes the effect of environmental factors, such as moisture content, pH, and temperature, on reaction rates. The model includes not only biodegradation processes for carbon compounds (acetate, CO2, CH4), but also for nitrogen compounds involved in nitrification and denitrification due to their significance in landfills. Two example runs to simulate anaerobic and aerobic waste were conducted for a single landfill unit cell by changing the organic content and diffusion coefficient. 相似文献
2.
Soichi?Kugimiya Ritsuo?NishidaEmail author Masayuki?Sakuma Yasumasa?Kuwahara 《Chemoecology》2003,13(4):169-175
Summary. Males of the German cockroach, Blattella
germanica, secrete a pheromonal substance from the abdominal tergal glands,
which elicits a feeding response in females during the sequential courtship behavior.
The nuptial secretion consists predominantly of a synergistic mixture of sugars
and phospholipids. Cholesterol and a series of amino acids, which are also
components of the males glandular secretion, significantly enhanced the phagostimulant
activity of the sugar components. The nuptial feeding behavior of the female cockroach
is therefore elicited by a complex assortment of nutritive components in the male
tergal secretion, including sugars, phospholipids, cholesterol, and amino acids. These
results indicate that a mixture of primary metabolites, and not of specific secondary
metabolites, serves as a pheromonal cue that appeals to the females gustatory sense
and effectively brings her to the precopulatory position. Although the
male secretion consists of nutrients, we suggest that these compounds probably do not
represent a significant nutrient investment in females and their progeny but rather
function as a signal in the mating sequence of B. germanica. 相似文献
3.
Pharmacophagous acquisition of clerodendrins by the turnip sawfly (Athalia rosae ruficornis) and their role in the mating behavior 总被引:3,自引:0,他引:3
Summary. Adults of the turnip sawfly, Athalia rosae ruficornis (Tenthredinidae: Hymenoptera), frequently visit a plant, Clerodendron trichotomum (Verbenaceae), and feed pharmacophagously on the glandular trichomes on the leaf surface. A series of neo-clerodane diterpenoids (e.g. clerodendrins B and D) contained in glandular organs on the leaf surface stimulate feeding of the sawflies (both males and
females). The adults fed selectively on the trichomes were found to sequester a series of the bitter-tasting diterpenes (clerodendrin
D, ajugachin A, athaliadiol) in the body tissues, which suggested their primary role as defense substances against predators.
Females fed on Clerodendron leaves or on clerodendrin B or D were more successful in mating than unfed females. Thus, females seem to obtain an advantage
in mating success through the acquisition of the defensive principles from the Clerodendron plant.
Received 20 April 1999; accepted 29 June 1999 相似文献
4.
Mohiuddin KM Otomo K Ogawa Y Shikazono N 《Environmental monitoring and assessment》2012,184(1):265-279
The Tsurumi, a class-one Japanese river, has a significant metal loading originating from urban environment. Water and sediment
samples were collected from 20 sites in winter and summer, 2009 and were analyzed to determine and compare the extent of different
trace element enrichment. A widely used five-step sequential extraction procedure was also employed for the fractionation
of the trace elements. Concentrations of zinc, copper, lead, chromium, and cadmium were three to four times higher than that
of reference values and downstream sediments are much more polluted than the upstream sites. Geochemical partitioning results
suggest that the potential trace metal mobility in aquatic environment was in the order of: cadmium > zinc > lead > copper
> cobalt > chromium > molybdenum > nickel. About 80.2% zinc, 77.9% molybdenum, 75.3% cobalt, 63.7% lead, 60.9% copper, 55.1%
chromium, and 39.8% nickel in the sediment were contributed anthropogenically. According to intensity of pollution, Tsurumi
river sediments are moderately to heavily contaminated by zinc, lead, and cobalt. Enrichment factor values demonstrated that
zinc, lead, and molybdenum have minor enrichment in both the season. The pollution load index (PLI) has been used to access
the pollution load of different sampling sites. The area load index and average PLI values of the river were 7.77 and 4.93
in winter and 7.72 and 4.89 in summer, respectively. If the magnitude of pollution with trace metal in the river system increases
continuously, it may have a severe impact on the river’s aquatic ecology. 相似文献
5.
Yasumasa Ogawa Kento Sakakibara Li Wang Koichi Suto Chihiro Inoue 《Environmental monitoring and assessment》2014,186(10):6757-6770
Fourteen different alkaline coal fly ashes (CFAs) were used for the experiment, in which each sample was mixed with water to be 28.6 % of water content (wt/wt) and aged for 1–4 weeks at 10–30 °C. This simple treatment is advantageous for decreases in water-soluble B, F, Cr, and As. Compared to non-aged CFAs, their water-soluble fractions remained 0.56–88 %, 21–85 %, 0.37–93 % and 2.6–88 %, respectively, after aging for a week at 20 °C, although the amounts of Cr and As released from some CFA samples increased. Considering the significant decrease in elution of sulfate, Ca and Al after aging, the immobilization, namely prevention of toxic element elution, could be related to formation of secondary minerals such as portlandite, gypsum and ettringite. Immobilization of B and Cr tends to proceed preferentially under colder conditions. Aging at higher temperatures enhances the leachability of Cr in some CFA samples. Contrary to the behavior of B and Cr, water-soluble F effectively decreases under warmer conditions. 相似文献
6.
Sang-Yul Kim Nobutoshi Tanaka Toshihiko Matsuto Yasumasa Tojo 《Waste management & research》2005,23(3):220-229
Two new pre-treatment methods (water-washing/carbonation and carbonation/phosphate stabilization) of municipal solid waste (MSW) incinerator residues were evaluated by column leaching tests under aerobic conditions and anaerobic conditions (which were changed to aerobic conditions after 10 months). A mixture of bottom ash and fly ash (5:1 ratio) was pre-treated using each method. Shredded incombustible residues (SIR) were added to each ash preparation in proportions similar to the ratios present in landfills. For comparison, landfill wastes typical of Japan, namely, a mixture of bottom ash, chelating-pre-treated fly ash, and SIR, were also examined. Leachate samples were collected periodically and analysed over a 15-month period. When compared with chelating pretreatment, both water-washing/carbonation and carbonation/ phosphate stabilization reduced the leaching of Pb, Al, and Cu by about one to two orders of magnitude. Moreover, the initial concentrations of Ca and Pb in leachates from column of water-washing/carbonation were 56-57% and 84-96% less than those from the column of carbonation/phosphate stabilization. Therefore, water-washing/carbonation was considered to be a promising approach to obtain early waste stabilization and to reduce the release of heavy metals to near-negligible levels. The leaching behaviour of elements was also discussed. 相似文献
7.
Norio Tanaka Teruko Demise Mitsuhiro Ishii Yasumasa Shoji Masahiro Nakaoka 《Marine Biology》2011,158(4):871-882
Massive losses of eelgrass Zostera marina beds in Japan have occurred over the past 100 years. Toward their restoration, transplantation of eelgrass has been attempted
in some areas, including Tokyo Bay. This study examined population genetic structures and gene flow in eelgrass in Tokyo Bay
to establish guidelines for conducting restoration. Genotypes of a total of 360 individuals from 12 beds were determined using
five microsatellite markers. The eelgrass beds in inner bay had above-average genetic diversity. A neighbor-joining tree based
on F
ST values among beds revealed that a strong gene flow had occurred among six beds in the inner bay. Genetic assignment testing
of drifting shoots indicated that those with seeds migrate in both directions between the inner and outer bay. We suggested
that the restoration of eelgrass in the innermost part of Tokyo Bay, where natural habitats have been lost, should be conducted
using the inner bay beds. 相似文献
8.
The white millipede Eucondylodesmus elegans Miyosi (Polydesmida: Doratodesmidae) secretes odoriferous droplets from the glands on both lateral surfaces of its body segments. The secretion was shown to be composed of a mixture of (1E)- and (1Z)-2-nitroethenylbenzenes (2-3 microg per millipede), identified by GC/MS analyses and synthesis. This is the first identification of these compounds as natural products. A granulated sugar block baited with the synthetic compound (more than 0.71 microg) demonstrated repellent activity against foraging wild ants, indicating that the compound functioned as a defense substance against potential predators. alpha,beta,2,3,4,5,6-d7-(1E)-2-Nitroethenylbenzene was detected by GC/MS analysis in the millipede secretion after feeding with alpha,beta,beta,2,3,4,5,6-d8-L-phenylalanine, indicating that L-phenylalanine is the precursor of these compounds. 相似文献
9.
Kunisue T Nakanishi S Watanabe M Abe T Nakatsu S Kawauchi S Sano A Horii A Kano Y Tanabe S 《Environmental pollution (Barking, Essex : 1987)》2005,136(3):465-476
Concentrations of persistent organochlorines (OCs) such as polychlorinated dibenzo-p-dioxin (PCDDs), dibenzofurans (PCDFs), biphenyls, dichlorodiphenyltrichloroethane and their metabolites (DDTs), hexachlorocyclohexane isomers, hexachlorobenzene, and chlordane compounds were determined in genital organs of pet dogs and cats and pet foods from Japan. Levels of OCs in dogs were relatively lower than those in cats, while residue levels in their diets were almost similar, implying that accumulation and elimination mechanisms of these contaminants are different between dogs and cats. When bioconcentration factors (BCFs) were estimated from concentrations of OCs in dogs, cats, and their diets, BCFs of all the OCs except PCDD/DFs exceeded 1.0 in cats. On the other hand, in all the dogs, BCFs of DDTs were below 1.0, suggesting that dogs do not bioconcentrate DDTs. Furthermore, BCFs of all the OCs except PCDD/DFs in dogs were notably lower than those in cats, suggesting that dogs have higher metabolic and elimination capacity for these contaminants than cats. When residue levels of OCs in livers, adipose tissue, and genital organs of two pet dogs were examined, hepatic sequestration of PCDD/DFs and oxychlordane was observed. 相似文献
10.
Summary A crude cuticular extract from 3450 virgin 9–13 day old female fruit flies(Drosophila virilis), was subjected to chromatography accompanied by bioassay for sex pheromone activity. After three chromatographic steps, fractions containing active monoenes and dienes were obtained. Chemical analysis by infrared absorption, gas liquid chromatography and gas chromatography/mass spectrometry of the active fraction indicated that active monoenes were comprised chiefly of (Z)-11-pentacosene (abbreviated (Z)-11-C25:1), (Z)-13-C27:1, (Z)-13- and (Z)-14-C29:1. Synthetic monoenes were made, and only (Z)-11-C25:1 elicited good courtship behaviour in maleD. virilis. Therefore it was concluded that (Z)-11-C25:1 was a major sex pheromone. A total of 16.2±1.32 µg of cuticular hydrocarbons was isolated from 10 day old females, including 5.9±0.56 µg of (Z)-11-C25:1. An additive effect was suggested from the higher observed courtship response when using a mixture of active dienes with the active monoene. 相似文献