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161.
We aimed to evaluate whether environmental factors affect the persistence of bromadiolone in baits in field treatment. Baits were distributed in three soils according to two types of distribution: (1) artificial galleries conform to agricultural practices; (2) storage cavities to mimic bait storage by voles. Persistence was evaluated for 30 days in galleries and 80 days in storage cavities in autumn and spring. The decrease of bromadiolone concentrations was described by a first-order kinetic model. In galleries, the half-lives ranged from 3.0 to 5.1 days in autumn and from 5.4 to 6.2 days in spring. The half-lives were similar between soils and seasons but the pattern of persistence differed lightly for two soils between seasons. Half-lives in storage cavities, 42.7 and 24.6 days in autumn and spring respectively, were longer than in galleries. To conclude, both soil characteristics and climatic conditions weakly influence persistence, while bait storage lengthens it dramatically.  相似文献   
162.
Summary. Worker postpharyngeal gland (PPG) chemistry of Pachycondyla apicalis constitutes a blend of hydrocarbons including alkanes, alkenes, and alkadienes, with 5,9-pentacosadiene, 5,9-heptacosadiene and 5,9-nonacosadiene as the major products as well as fatty acids. There is a large congruency between the PPG and cuticular hydrocarbons, however the latter had higher proportion of tricosane and pentacosane, but only traces of fatty acids. These ants have a well-developed cuticular hair brush on the front legs that they frequently pass through the mouth while grooming. Since these brushes have higher amounts of hydrocarbons than either the middle or hind legs, we hypothesized that they are involved in hydrocarbon circulation. We assessed the role of the front basitarsal brush in hydrocarbon circulation by isolating them from the buccal cavity, either by restraining the front legs or by blocking the mouth with glue. In both experiments, preventing contacts between the basitarsal brushes and the mouth for 24 hrs resulted in a considerable increase in hydrocarbon amounts in the brushes with a parallel decrease in the PPG. When the ants were kept alive for an additional 24 hrs after their legs were freed, hydrocarbon amounts in both the PPG and the front legs returned to normal. Analyses of crop content revealed the same hydrocarbons profile as in the PPG, but their amounts were very variable and there were no differences in amounts between the treatment and the control. We assume that part of the PPG hydrocarbons are cleared via the alimentary canal. Grooming behavior of ants restrained for 24 hrs and then freed was followed for four hours thereafter. There was a significant increase in total grooming during the first third and fourth hour, but not during the second. Grooming involving the front legs-mouth, and front legs-antennae, and the front and hind legs was especially intensive during the first hour. Grooming involving the hind legs - body was more intensive in the treated ants during the third hour following their release. We conclude that the front basitarsal brush is a site of hydrocarbon accumulation and that the PPG receives frequent charging during self-grooming.  相似文献   
163.
The need to collect data representative of overall urban pollution is all-important in order to monitor the population exposure. High spatial resolution monitoring using diffusive samplers allows studying of the urban pollutant distribution, thus enabling deeper investigation of their generation and diffusion mechanisms. Nevertheless, such a monitoring campaign has a certain cost. In this study we point out how to find the best compromise between the number of necessary measurements and the affordable costs for monitoring campaigns. We also describe an innovative method for the proper design of a fixed urban monitoring network by means of preliminary high spatial resolution campaigns using diffusive samplers. Four European capital cities (Dublin, Madrid, Paris and Rome) were monitored six times, each time for seven days. Benzene, toluene, ethylbenzene, xylenes (BTEX) and NO(2) concentrations were measured at 146 sites in Dublin, 293 in Madrid, 339 in Paris and 290 in Rome. Multiscale grids have been drawn which ranged in mesh size from 500 m to 2 km. The statistical processing of data produced a twofold result: the creation of isoconcentration maps with geostatistical procedures, and an algorithm aimed at locating the minimum number of sampling sites where the fixed monitoring stations should be placed. Average urban levels estimated on the basis of these selected sites differ by less than 8% from those calculated on the whole populations of the sampled points. The aim of this work is to investigate how far the resolution of a monitoring campaign of urban pollution by diffusive sampling can be reduced, thus making the monitoring less expensive in terms of human and financial resources, while preserving the same quality of the results that could be achieved with a higher resolution. We found that there is no significant loss of information when the resolution of the monitoring grid for BTEX is lowered to a mesh size of 1.85 km, that is a sampling site each 3.4 km(2), and that the minimum number of sampling sites to be used is N = 0.29 A, where A is the urban surface to be monitored (in km(2)). As the spatial distribution of NO(2) is less sensitive to the distance from the emission source than that of BTEX, this relationship could be retained as a valid lower limit for the mesh grid size also for NO(2) monitoring.  相似文献   
164.
Several treatment processes of mixed sludge naturally contaminated with nonylphenol ethoxylates (NPE) were compared in order to evaluate their efficiency for the removal of these endocrine disrupters. Anaerobic and aerobic treatments were carried out in continuous stirred tank reactors, operated separately or combined together, at mesophilic and thermophilic temperatures and with or without ozone post-treatment. Anaerobic mesophilic removal of NPE consisted of complete removal of nonylphenol diethoxylate, incomplete removal of nonylphenol monoethoxylate and non stoechiometric production of nonylphenol, with consequently a NPE removal of 25%. At thermophilic temperature, anaerobic digestion led to an increase of the total solids removal efficiency, while improving NPE degradation (30%). Under thermophilic aerobic condition, the three compounds were removed simultaneously with a NPE removal efficiency higher than under anaerobic condition (39%). This removal is always well correlated to the total solids removal meaning that bioavailability remains the main limiting factor. Combination of either thermophilic aerobic-mesophilic anaerobic or mesophilic anaerobic-ozonation treatments enhanced the NPE removal by comparison to single systems (45% and 48%, respectively). These results confirm the high potential of existing and up-grading sewage sludge treatments to degrade such refractory and aged compounds.  相似文献   
165.

Since the beginning of the Industrial Revolution, the manufacturing industry has been crucial for economic growth. China’s manufacturing activity began after China approved and opened legal reform to the rest of the world in 1978. There are usually three stages of development, including the catch-up period. At the same time, they reflect the private economic sector, manufacturing, and foreign exchange industries, and the opening up to the international markets. This advancement comes along with high energy consumption, leading to a high rate of pollution. Therefore, this study provides a detailed overview of the “Made in China 2025” pilot target and implementations of policies to achieve a carbon-neutral goal. We assessed the efficiency of implementing policies in the Chinese manufacturing sector and recommended decision-making policies to achieve the “Made in China 2025” plan and the 2030 carbon-neutral goal. The Quantitative Strategic Programming Matrix (QSPM) and SWOT analysis matrix were used to put forward some development strategies to transform and upgrade China’s manufacturing industry by combining relevant strategic theories. This study is significant in terms of energy-saving and carbon emission-reducing policy implementations for the Chinese manufacturing industry. In addition, we suggested some measures to achieve a sustainable environment in line with carbon-neutral policies.

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