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141.
142.
Ammonia (NH3) emission from livestock production causes undesirable environmental effects and a loss of plant-available nitrogen. Much atmospheric NH3 is lost from livestock manure applied in the field. The NH3 emission may be reduced by slurry injection, but slurry injection in general, and especially on grassland, increases the energy demand and places heavy demands on the slurry injection techniques used. The reduction in NH3 emission, injection efficiency, and energy demand of six different shallow slurry-injection techniques was examined. The NH3 emission from cattle slurry applied to grassland was reduced by all the injectors tested in the study, but there were major differences in the NH3 reduction potential of the different types of injectors. Compared with the trailing hose spreading technique, the NH3 loss was reduced by 75% when cattle slurry was injected using the most efficient slurry injection technique, and by 20% when incorporated by the least efficient injection technique. The reduction in NH3 emission was correlated with injection depth and the volume of the slot created. The additional energy demand for reducing ammonia emissions by slurry injection was approximately 13 000 kJ ha(-1) for a 20% reduction and 34 000 kJ ha(-1) for a 75% reduction. The additional energy demand corresponds to additional emissions of, respectively, 5.6 and 14.5 kg CO2 per ha injected.  相似文献   
143.
Niels Nyholm 《Chemosphere》1990,21(12):1477-1487
Manometric respirometry (UK-MITI test) was found convenient for biodegradability testing of poorly soluble chemicals. Various dispersion techniques were evaluated with anthraquinone (solid) and di-isooctylphtalate (liquid). Application on silica gel via a solvent (dichloromethane) was found generally suitable. Ultrasonic dispersion was found suitable only if a stable emulsion forms.  相似文献   
144.
In the light of the prevailing goal to keep global temperature increase below 2° and recent challenges to reach a global climate agreement in the near term, linking emissions trading schemes has emerged as a prominent complementing policy option. To this end, we explicitly assess (1) the macroeconomic welfare impacts and (2) the trade-based competitiveness effects of linking the European Union (EU) Emissions Trading Scheme in the year 2020. A stylized partial market analysis suggests that, independently of regional cost characteristics, the integration of emissions trading schemes (ETS) yields economic welfare gains for all participating regions. A computable general equilibrium analysis confirms these findings at the macroeconomic level: The economic efficiency losses from emissions regulation are diminished for both EU Member States and non-EU regions by linking ETS. However, the quantitative analysis suggests opposite trade-based incentives for linking up: while EU Member States improve their terms of trade by integrating with emerging ETS, non-EU linking candidates face competitiveness losses by linking. We conclude that, for non-EU regions, the attractiveness of linking ETS is a matter of priorities for economic welfare or international competitiveness. If these priorities are hierarchized in favor of welfare, the globalization of the carbon market could become a promising policy option complementing the efforts to reach a global climate agreement in 2015.  相似文献   
145.
Although sex pheromone communication in the genus Ostrinia (Lepidoptera: Crambidae) has been studied intensively, acoustic communication in this genus has not been explored. In this study, we report that male-produced ultrasound serves as a courtship song in the Asian corn borer moth, O. furnacalis. Upon landing close to a pheromone-releasing female, a male showed a series of courtship behaviors involving emission of ultrasound. The sounds were produced when the wings were vibrated quickly in an upright position. The male song was composed of chirps, i.e., groups of pulses (duration of a chirp = 58.9 ms, 8.8 pulses/chirp), with a broadband frequency of 25–100 kHz. In flight tunnel experiments, deaf and hearing females showed a significant difference in the incidence of three behavioral responses to courting males, i.e., immediate acceptance, acceptance after walking, and rejection. Deaf females showed more ‘rejection’ and less ‘acceptance after walking’ than hearing females, indicating that the detection of male-produced ultrasound plays an important role in the acceptance of a male. The findings are discussed in the context of exploitation of receiver bias and mate choice.  相似文献   
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