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In this study, melB tyrosinase was applied for enzymatic removal of linear and branched p-alkylphenols from aqueous solutions. First, systematic studies were carried out to estimate the effects of the process parameters such as the temperature, pH value, and enzyme dose on quinone conversion of p-cresol as a model phenol compound. A variety of p-alkylphenols were removed from aqueous solutions through the tyrosinase-catalyzed quinone conversion and subsequent nonenzymatic adsorption of quinone derivatives on chitosan beads at pH 6.0 and 30 °C under the optimum conditions determined for p-cresol. The % removal values of 98–100 were obtained for p-n-alkylphenols. Branched p-alkylphenols with a weak estrogenic activity containing 4-tert-butylphenol and 4-tert-pentylphenol, which underwent no quinone conversion by commercially available mushroom tyrosinase in the absence of H2O2, were also effectively removed by further increasing either the melB tyrosinase concentration or the amount of added chitosan beads. The present technique is much effective in the fact that a series of reactions rapidly progress under mild conditions and the chitosan beads can be readily separated from the reaction medium after the enzymatic treatment.  相似文献   
3.
A questionnaire survey was conducted to determine the current status of home medical care (HMC) waste collection by nurses for individual items and whether the collection rate differs with city size. The questionnaire was mailed to 1,022 nursing offices, of which 645 offices provided valid responses. Offices were classified into three groups according to the local population size. Responses indicated that used syringes and needles, except for pen-type self-injection needles, were collected by >50% of HMC nurses. On the other hand, enteral nutrients, nutritional adjustment diet vessels, feeding tubes, portable injectors, ventilator masks, endotracheal suction catheters, tracheal cannulas, continuous ambulatory peritoneal dialysis (CAPD) bags, and urinary catheters and bags had a low collection rate in comparison with syringes or needles. The collection percentage of used syringes, needles, and infusion needles (p < 0.05) and that for infusion bags, tubes, and catheters (p < 0.001) differed among the three population groups. Although municipalities are responsible for collect all HMC waste, sharp or infectious items should be collected by HMC doctors or nurses. On the contrary, nonhazardous HMC waste should be collected by municipalities.

Implications: This paper illustrates the status of waste collection of individual home medical care (HMC) items by HMC nurses. Infectious waste, such as needles and syringes, is collected by nurses. The collection rate of infectious waste by nurses in large cities was low compared with that in small cities. Although municipalities are responsible for collecting all HMC waste, sharp or infectious items should be collected by HMC doctors or nurses, whereas nonhazardous HMC waste should be collected by the municipalities.  相似文献   

4.
Summary. In this paper we report on the chemical basis for trail recognition in Lasius nipponensis. On and near trails in the field, workers became aggressive against conspecific intruders and succeeded in protective contests, while intruders usually avoided confrontation. Such asymmetric interactions were also observed in the laboratory when two non-nestmate workers were sequentially placed in a clean glass dish, while mutual aggression was observed when they were placed simultaneously. Asymmetric aggression was also observed when the workers were placed in a dish previously conditioned by other workers, or when the dish was treated with the hexane rinse of the conditioned dish. The rinse contained a series of hydrocarbons, in which components and proportion were almost identical to those of the cuticular hydrocarbons of the workers, except for a lack of n-alkanes. Amounts of the hydrocarbons that remained on the dish were very small when all the tarsi of the workers were incapacitated. We therefore consider that the hydrocarbons are not adhesion of the cuticular hydrocarbons but secretion from the tarsi of workers, and serve as a key signal for trail recognition in this ant.  相似文献   
5.
Biological hydrogen production was investigated using biomass in palm oil mill effluent (POME) and artificial wastewater containing 10g glucose under anaerobic fermentation in a batch process. Activated POME sludge and different types of composts were collected as sources of inocula for the study. The anaerobic microflora was found to yield significant amounts of hydrogen. The experimental results show that the gas composition contained hydrogen (66–68%) and carbon dioxide (32–34%). Through out the study, methane gas was not observed in the evolved gas. The hydrogen production was accompanied with the formation of acetate and butyrate. Furthermore, the cumulative hydrogen data were fitted to a simple model developed from Gompertz Equation, where the lag phase time, hydrogen production potential and hydrogen production rate at various conditions were quantitatively estimated.  相似文献   
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Changes of tree-ring widths of Japanese black pine (Pinus thunbergii Parl.) trees growing in air-polluted and unpolluted areas were analyzed. In the stand close to an industrial complex, a large reduction in the series of tree-ring index (TRI), which were computed by removing endogenous effects from the measured series, appeared from the 1960s to 1970s. This reduction in radial tree growth was not explained by the climatic response model calibrated for a pre-pollution period. TRI changes corresponding with changes in concentrations of sulfur dioxide (SO(2)), and a significant negative correlation between the TRI and SO(2) concentration were found in the polluted area. Reduction in tree-ring growth was not seen in the unpolluted area. These results indicate that the past reduction in the growth of Japanese black pine trees growing in an industrial area was mainly caused by SO(2).  相似文献   
8.
The volcanic plate made pillar cooler system is designed for outdoor spaces as a heat exchanging medium and reduces the outcoming air temperature which flows through the exhaust port. This paper proposes the use of artificial neural networks (ANNs) to predict inside air temperature of a pillar cooler. For this purpose, at first, three statistically significant factors (outside temperature, airing and watering) influencing the inside air temperature of the pillar cooler are identified as input parameters for predicting the output (inside air temperature) and then an ANN was employed to predict the output. In addition, 70%, 15% and 15% data was chosen from a previously obtained data set during the field trial of the pillar cooler for training, testing and validation, respectively, and then an ANN was employed to predict inside air temperature. The training (0.99918), testing (0.99799) and validation errors (0.99432) obtained from the model indicate that the artificial neural network model (NARX) may be used to predict inside air temperature of pillar cooler. This study reveals that, an ANN approach can be used successfully for predicting the performance of pillar cooler.  相似文献   
9.
Kobayashi T  Morimoto K  Tatsumi K 《Chemosphere》2008,70(11):2002-2008
Plants contain a wide variety of chemicals, some of which may have similar chromatographic behavior to polycyclic aromatic hydrocarbons (PAHs). During solid phase extraction (SPE) with Si-gel for instance, the co-elution of carotene-like colored compounds with PAHs has been observed. In this paper, liquid–liquid extraction was applied for the separation and subsequent analysis of PAHs from plant extracts. PAHs containing 2–6 rings, which include naphthalene, phenanthrene, pyrene, benzo[a]pyrene and benzo[ghi]perylene, were used as representative target chemicals. Carotene-like compounds extracted from Komatsuna (Brassica campestris) shoot by acetone followed by Si-gel treatment were incorporated as undesired components in the model matrix. Results showed the feasibility of employing either acetonitrile or 2% (w/v) KOH–methanol as solvents for high PAHs recovery and low extraction of colored fraction. For acetonitrile, 86.9–93.5% of each PAH could be recovered after three extraction cycles (relative standard deviation, RSD < 1.6%) with only about 10% co-extraction of colored fraction. For 2% KOH–methanol, PAHs recoveries ranging from 79.3% to 83.1% after five cycles (RSD < 1.5%) were achieved while the percent extraction of colored fraction was also low at 10%. The relatively higher selectivity of the solvents for PAHs over the colored fraction as well as the solubility of the matrix solution in the solvent may have contributed to these results. On this basis, liquid–liquid extraction is very useful for the pre-treatment of plant extracts for PAHs analysis.  相似文献   
10.
Syntheses of some metabolites of ubiquinone and of related compounds are described. Idebenone (QSA-10), a methyl-dimethoxy-benzoquinone bearing an omega-hydroxydecyl side chain in 3-position, restored the oxidation of succinate and of NADH in ubiquinone-depleted mitochondrial preparations and showed a stabilizing effect on lysosomal membranes and an inhibitory effect on cAMP-phosphodiesterase. It inhibited lipid peroxidation in canine brain mitochondria and in microsomes from canine brain and rat liver. Administered orally to rats, it increased the respiratory control index for glutamate and succinate oxidation but had no effect on the ADP/O2 ratio. Pharmacological effects of idebenon are also briefly discussed.  相似文献   
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