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201.
The decolouration and mineralization of reactive dye C.I. Reactive Black 5, a well-known representative of non-biodegradable azo dyes, by means of ultrasonic irradiation at 20, 279 and 817kHz has been investigated with emphasis on the effect of various parameters on decolouration and degradation efficiency. Characterization of the used ultrasound systems was performed using calorimetric measurements and oxidative species monitoring using Fricke and iodine dosimeter. Experiments were carried out with low frequency probe type, and a high-frequency plate type transducer at 50, 100 and 150W of acoustic power and within the 5-300mg/L initial dye concentration range. Decolouration, as well as radical production, increased with increasing frequency, acoustic power, and irradiation time. Any increase in initial dye concentration results in decreased decolouration rates. Sonochemical decolouration was substantially depressed by the addition of 2-methyl-2-propanol as a radical scavenger, which suggests radical-induced reactions in the solution. Acute toxicity to marine bacteria Vibrio fischeri was tested before and after ultrasound irradiation. Under the conditions employed in this study, no toxic compounds were detected after 6h of irradiation. Mineralization of the dye was followed by TOC measurements. Relatively low degradation efficiency (50% after 6h of treatment) indicates that ultrasound is rather inefficient in overall degradation, when used alone. 相似文献
202.
Cooperative communications has been actively studied as an effective approach to achieve multi-user/spatial diversity gains
and better overall system performance by coordinating multiple users in a dynamic wireless network to share their resources
and capabilities. Based on the concept of cooperative communications, this paper proposes and analyzes a Busy Tone based cooperative
Medium Access Control (MAC) protocol, namely BTAC, for multi-rate Wireless Local Area Networks (WLANs). A cross-layer Markov
chain model is then developed to evaluate the performance of BTAC under dynamic wireless channel conditions. Analytical and
simulation results show our BTAC protocol is simple, robust, fully compatible with the IEEE 802.11b standard and can achieve
better throughput and delay performance than the standard Distributed Coordination Function (DCF) protocol and the recently-proposed
CoopMAC protocol. 相似文献
203.
Ray AM Zunič A Alten RL McElfresh JS Hanks LM Millar JG 《Journal of chemical ecology》2011,37(2):173-178
We report the identification, synthesis, and field bioassays of a female-produced sex attractant pheromone component of the
cerambycid beetle Ortholeptura valida (LeConte). Headspace volatiles from females contained a female-specific compound, (Z)-11-octadecen-1-yl acetate, which elicited a strong response from antennae of adult males in coupled gas chromatography-electroantennogram
analyses. In field bioassays, significant numbers of males were collected by traps baited with this compound. The pheromone
represents a new structural class of cerambycid pheromones, and is the first pheromone identified for a cerambycid species
in the subfamily Lepturinae. 相似文献
204.
Nina Recek Matej Holc Alenka Vesel Rok Zaplotnik Peter Gselman Miran Mozeti
Gregor Primc 《International journal of molecular sciences》2021,22(13)
Seeds of common bean (Phaseolus vulgaris L.), of the Etna variety, were treated with low-pressure oxygen plasma sustained by an inductively coupled radiofrequency discharge in the H-mode for a few seconds. The high-intensity treatment improved seed health in regard to fungal contamination. Additionally, it increased the wettability of the bean seeds by altering surface chemistry, as established by X-ray photoelectron spectroscopy, and increasing surface roughness, as seen with a scanning electron microscope. The water contact angle at the seed surface dropped to immeasurably low values after a second of plasma treatment. Hydrophobic recovery within a month returned those values to no more than half of the original water contact angle, even for beans treated for the shortest time (0.5 s). Increased wettability resulted in accelerated water uptake. The treatment increased the bean radicle length, which is useful for seedling establishment in the field. These findings confirm that even a brief plasma treatment is a useful technique for the disinfection and stimulation of radicle growth. The technique is scalable to large systems due to the short treatment times. 相似文献
205.
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207.
In the last decade local policymakers and community health officials have been using a Health Impact Assessment (HIA) strategy to assess the health impacts of their policy decisions. The HIA research design is founded on the mixed method research approach (integration of quantitative and qualitative data slices within a single investigation) to get as comprehensive assessment as possible of the expected impacts. The HIA literature has yet to provide any guidelines on how community health investigators should conduct a mixed-method HIA research. We conducted a content analysis of 100 HIAs executed around the world published between 1999 and 2011 and analysed their research methodologies. Observations generated from the analysed HIAs were used to establish an ‘HIA mixed method model’ by which a series of mixed-method design guidelines were used to help community health researchers improve the analytical capabilities in their future HIA investigations. 相似文献
208.
Moness Mohammed Gaber Lamya Hussein Aziza I. Ali Hanafy M. 《Journal of Electronic Testing》2022,38(4):395-417
Journal of Electronic Testing - As the complexity and scope of VLSI designs continue to grow, fault detection processes in the pre-silicon stage have become crucial to guaranteeing reliability in... 相似文献