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1.
Removal of thiobencarb in aqueous solution by zero valent iron   总被引:2,自引:2,他引:0  
A cost-effective method with zero valent iron (ZVI) powder was developed for the purification of thiobencarb (TB)-contaminated water. The removal treatment was performed in the batch system. A sample solution of 10 ml containing 10 microg ml(-1) of TB could be almost completely treated by 100mg of ZVI at 25 degrees C for 12h of treatment time. Since the formation of chloride ion in the aqueous solution during the treatment of TB was observed, the removal of TB with ZVI may contain two processes: reduction (degradation) and adsorption. Because the present treatment for TB is simple, easy handling and cheap, the developed technology with ZVI can contribute to the treatment of agricultural wastewaters.  相似文献   
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Two cases with a large cystic mass within the placenta are reported. By ultrasonography, it was found that both women had a subchorionic hypoechoic lesion (11.0 × 4.8 × 4.0 cm and 6.6 × 3.7 × 2.2 cm, respectively) at 24 and 35 weeks of gestation, respectively. In both cases, turbulent blood flow generated by a pulsatile jet flow (pulse rate; 40 to 60 beats per minute) into the cystic lesion seen on real-time imaging and lesions being low intensity on T1-weighted and isointensity on T2-weighted magnetic resonance image suggested that they contained fresh maternal blood. In both cases, the sonolucency of the lesions did not change until cesarean deliveries of females, both of whom were small-for-gestational-age infants (1940 g at 37 weeks and 2195 g at 37 weeks, respectively). Biochemical analysis of the fluid in the cystic lesion sampled during the cesarean section in the latter case confirmed that the fluid had originated from the maternal blood. These lesions histologically corresponded to large avillous areas surrounded by normal villi. Thus, a huge placental lake was diagnosed in both cases. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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The occurrence of mate solicitation by virgin females was investigated in the butterfly Eurema hecabe. Young (1-day-old) virgin females rarely showed mate solicitation to male model, however, old (at least 6-day-old) virgin females frequently showed such flight. The duration of solicitation was significantly longer in older females than in younger ones. The age-related behavioral change occurs with female oogenesis (Hiroki and Kato 1996), and such behavior may thus be a result of female adaptation to maximize their fecundity. Received: 6 November 1997 / Accepted in revised form: 29 June 1998  相似文献   
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This paper reports the preparation of galactomannan/ionic liquid composite materials from the corresponding ion gels. Three kinds of galactomannans, that is, fenugreek gum (FG), guar gum (GG), and locust bean gum (LBG) and an ionic liquid of 1-butyl-3-methylimidazolium chloride (BMIMCl) were used. When the galactomannan/BMIMCl gels were immersed in ethanol, followed by dryness under reduced pressure, the galactomannan/BMIMCl composite materials were obtained. The crystalline structures of galactomannans in the materials were evaluated by the powder X-ray diffraction measurement. The mechanical property of the FG/BMIMCl composite material under compressive mode was superior compared with the GG and LBG/BMIMCl composite materials. Then, FG films compatibilized with polymeric ionic liquids (PILs) were also prepared by in situ radical polymerization of polymerizable ionic liquids, 1-(3-acryloyloxypropyl)-3-vinylimidazolium bromide and 1-methyl-3-vinylbenzylimidazolium chloride by AIBN in mixtures of FG with BMIMCl. The mechanical properties of the resulting films were affected by the FG/PIL ratios as well as the unit ratios in PILs.  相似文献   
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The composting process of different organic wastes both in laboratory and on a large-scale was characterized using CIELAB color variables to evaluate compost stability for the better application in agriculture. The time courses of the CIELAB variables of composting materials were determined directly from the bottom of a glass petri dish filled with dried and ground samples using a Minolta Color Reader (CR-13) calibrated with clean empty petri dishes placed on a white tile. To compare the proposed method with conventional methods, the same materials were also evaluated using commonly used compost stability evaluation indices. Most of the CIELAB variables of a compost made from a mixture of green tea waste and rice bran reached a plateau after 84 days of composting and showed strong relationships with the commonly used compost stability evaluation indices. The time needed for CIELAB variables, especially the L*and b* values, to stabilize at large-scale composting plants of cattle litter, farmyard manure, kitchen garbage and bark compost, were more or less similar to the times of maturation evaluated by the respective compost producers. The CIELAB color variable offers a new, simple, rapid and inexpensive means of evaluating compost stability and its quality prior to agricultural use.  相似文献   
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Flight performance is undoubtedly an important factor for behavioral success in flying insects. Though it is well-known that the flight performance is influenced by body temperature and body size, the relative importance of these factors is not well-understood. We performed laboratory experiments using the male-polymorphic damselfly Mnais costalis with larger territorial males and smaller non-territorial males in a population. We analyzed the effects of body temperature and body size, measured as the thoracic temperature and left hind-wing length, respectively, on two indices of flight performance: maximum lifting force and size-corrected lifting force. The latter is an index of acceleration that is related to aerial agility. The results showed that higher body temperature produced both larger maximum lifting force and larger size-corrected lifting force. In contrast, while larger size produced a larger maximum lifting force, it produced a lower size-corrected lifting force. The results of field measurements showed that territorial males had variable thoracic temperatures depending on the insolation in their territories. In contrast, non-territorial males had less variable and generally higher thoracic temperatures than territorial males as they are mostly found in sunny spots. Until now, the influence of body temperature on behavioral performance has remained unclear although considerable studies have suggested such influence. We showed, here, for the first time, combined effects of body size and body temperature on flight performance. We also showed that body temperature was influenced by the mating strategies of a damselfly. These findings provide new insights into the cost and benefits of territorial behavior in ectothermic animals.  相似文献   
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In this article, the systems for the collection and intermediate processing of used beverage cans (UBCs) are compared and analyzed, focusing on the time taken and the cost of processing, the energy consumption, and the emissions of CO2, SO x , and NO x , during the process. We found that cases where the UBCs were crushed in the discharging process gave better results, and how the UBCs were collected was the most important factor. It was more desirable to treat UBCs in one place than in two places. When the transportation distance was longer, the pressed form of UBCs was more convenient. When the transportation distance was short, the original form, the crushed form, and the shredded form of UBCs were all suitable. That is, the contribution of the transportation process to the evaluation was large when the transport distance was long, and the contribution of the treatment process was large when the transport distance was short.  相似文献   
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We have successfully prepared a bead-type adsorbent from two materials with different adsorption characteristics. Heavy metals were removed by greatly swollen egg shell membrane-conjugated chitosan beads. The egg shell membrane accumulated and removed precious metal ions from a dilute aqueous solution with a high affinity in a short contact time. Experiments suggested that chitosan beads could take up gold ions with great capacity and selectivity by conjugation with egg shell membrane. Under certain conditions, the selective removal of gold and copper in a mixture of gold and copper ions by egg shell membrane-conjugated chitosan beads was 100% and 2%, respectively. Egg shell membrane-conjugated chitosan beads can be seen as a promising material to recover gold in wastewater from various industries, such as electroplating.  相似文献   
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