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161.
While collating contributions and comments from 36 researchers, the coordinating authors accidentally omitted Dr. Suzanne Carrière from the list of contributing co-authors. Dr. Carrière’s data are described in Tables 1 and 3, Figure 2 and several places in the narrative. The new author list is thus updated in this article.  相似文献   
162.
A high volume aerosol sampler ("Grey Owl") has been designed and developed at the Radiation Protection Bureau, Health Canada. Its design guidance is based on the need for a low operational cost and reliable sampler to provide daily aerosol monitoring samples that can be used as reference samples for radiological studies. It has been developed to provide a constant air flow rate at low pressure drops (∼3 kPa for a day sampling) with variations of less than ±1% of the full scale flow rate. Its energy consumption is only about 1.5 kW for a filter sampling over 22,000 standard cubic meter of air. It has been demonstrated in this Fukushima nuclear accident related aerosol radioactivity monitoring study at Sidney station, B.C. that the sampler is robust and reliable. The results provided by the new monitoring system have been used to support decision-making in Canada during an emergency response.  相似文献   
163.
2,2,4-trimethyl, 1,3-pentanediol monoisobutyrate (TPM) is a widely used solvent found in water-based coatings. Ambient measurements of TPM are reported here for the first time. Although this compound has been previously measured in indoor air, this study illustrates successful detection and quantification of TPM in ambient air at three locations in Southern California: Pico Rivera, Azusa, and Riverside. TPM was detected in every sample collected, with concentrations ranging from 0.7 to 49.5 parts per trillion (ppt). Collections took place during summer 2009, fall 2009, winter 2009/2010, and spring 2010, for 5–7 days during each season. The highest mean concentrations were observed during the summer months for each city, when coating activities are typically at their highest.

Implications 2,2,4-Trimethyl, 1,3-pentanediol monoisobutyrate (TPM) is a widely used solvent found in water-based coatings. Ambient measurements of TPM are reported here for the first time. The highest mean concentrations were observed during the summer months for each city, when coating activities are typically at their highest. Unreacted TPM constitutes approximately 0.01% of the total nonmethane hydrocarbon (NMHC) concentrations in the Los Angeles air basin and given its slow reactivity rate in forming ozone, this would be an approximate upper limit for the fraction of ozone that it is responsible for forming.  相似文献   
164.
ABSTRACT

A field study was conducted to determine the effectiveness of watering in controlling PM10 emissions under high wind conditions. The focus of the study was the pickup of soil by a belly scraper at a landfill. Four low-volume PM10 samplers were positioned downwind of the storage pile (at two distances, 80 and 110 m, and two elevations, 1 and 3 m) and one was located upwind at 3 m elevation. Integrating nephelometers, which measure the particu-late light scattering coefficient, bsp, were also set up at locations 80 and 110 m downwind of the storage pile. Wind speed and direction were measured on-site. Samples were collected for two periods, one with and one without water being applied. Watering was effective at reducing PM10 emissions at wind speeds up to the maximum 18 m sec-1 observed at the landfill soil pickup operation. Measurement of bsp provided an indication of PM10 concentrations with better time resolution than samplers, but not with sufficient resolution, under the instrumental conditions used, to correlate with wind gusts.  相似文献   
165.
Continuous monitoring of exhaust flue gas has become a common practice in power plants in response to Federal Mercury and Air Toxics Standards (MATS) standards. Under the current rules, hydrochloric acid (HCl) is not continuously measured at most plants; however, MATS standards have been proposed for HCl, and tunable diode laser (TDL) absorption spectroscopy is one method that can be used to measure HCl continuously. The focus of this work is on the evaluation and verification of the operation performance of an HCL TDL over a range of real-world operating environments. The testing was conducted at the University of California at Riverside (UCR) spectroscopy evaluation laboratory. Laboratory tests were conducted at three separate temperatures, 25ºC, 100ºC, and 200ºC, and two distinct moisture levels for the enhanced temperatures, 0%, (2 tests) and 4%, over a concentration range from 0 ppmv to 25 ppmv-m at each of the elevated temperatures. The results showed good instrument accuracy as a function of changing temperature and moisture. Data analysis showed that the average percentage difference between the ammonia concentration and the calibration source was 3.33% for varying moisture from 0% to 4% and 2.69% for varying temperature from 25 to 100/200ºC. An HCl absorption line of 1.742 μm was selected for by the manufacturer for this instrument. The Hi Tran database indicated that CO2 is probably the only major interferent, although the CO2 absorption is very weak at that wavelength. Interference tests for NO, CO, SO2, NH3, and CO2 for a range of concentrations typical of flue gasses in coal-fired power plants did not show any interference with TDL HCl measurements at 1.742 μm. For these interference tests, CO2 was tested at a concentration of 11.9% concentration in N2 for these tests. Average precision over the entire range for all 10 tests is 3.12%.

Implications: The focus of this study was an evaluation of the operation performance of a tunable diode laser (TDL) for the measurement of hydrochloric acid (HCl) over a range of real-world operating environments. The results showed good instrument accuracy as a function of changing temperature from 25ºC to 200ºC and moisture from 0% to 4%. Such as an instrument could be used for continuous monitoring of exhaust flue gas in power plants once the Federal Mercury and Air Toxics Standards (MATS) standards have been fully implemented.  相似文献   

166.
The scale of investigation for disturbance-influenced processes plays a critical role in theoretical assumptions about stability, variance, and equilibrium, as well as conservation reserve and long-term monitoring program design. Critical consideration of scale is required for robust planning designs, especially when anticipating future disturbances whose exact locations are unknown. This research quantified disturbance proportion and pattern (as contagion) at multiple scales across North America. This pattern of scale-associated variability can guide selection of study and management extents, for example, to minimize variance (measured as standard deviation) between any landscapes within an ecoregion. We identified the proportion and pattern of forest disturbance (30 m grain size) across multiple landscape extents up to 180 km2. We explored the variance in proportion of disturbed area and the pattern of that disturbance between landscapes (within an ecoregion) as a function of the landscape extent. In many ecoregions, variance between landscapes within an ecoregion was minimal at broad landscape extents (low standard deviation). Gap-dominated regions showed the least variance, while fire-dominated showed the largest. Intensively managed ecoregions displayed unique patterns. A majority of the ecoregions showed low variance between landscapes at some scale, indicating an appropriate extent for incorporating natural regimes and unknown future disturbances was identified. The quantification of the scales of disturbance at the ecoregion level provides guidance for individuals interested in anticipating future disturbances which will occur in unknown spatial locations. Information on the extents required to incorporate disturbance patterns into planning is crucial for that process.  相似文献   
167.
The global diversity of human languages is a remarkable feature of our species, which requires a capacity for rapid vocal learning. Given that primate alarm calling systems have played an important role in the language origin debate, identifying geographic variation in primate alarm calls and understanding the underlying causal mechanisms are important steps to help uncover evolutionary precursors to language. This study investigates geographic variation in the alarm bark of the widely distributed African green monkey (Chlorocebus). To quantify geographic variation in spectral and temporal call structure, acoustic analysis was used to compare the adult male barks of green monkeys (Chlorocebus sabaeus) and two subspecies of vervet (Chlorocebus pygerythrus pygerythrus and Chlorocebus pygerythrus hilgerti). Playback experiments were also carried out to test whether adult male vervets would distinguish between the barks of own-group males, unknown conspecific males and green monkey males. Acoustic analysis showed that, whilst similar in overall structure, the barks of green monkeys could be distinguished from vervet barks with a high degree of accuracy; the barks of vervet subspecies could also be discriminated, although to a lesser degree. Males responded most strongly to unknown conspecific males’ barks, and exhibited responses typical of leopard-avoidance and territorial defence. Taken together, these findings indicate that variation in alarm calls can be best explained by phylogenetic distance, and that intra- and inter-species differences are relevant during social interactions. Moreover, barks may function as an alarm and display call, which could explain the observed sexual dimorphism in barks in this genus.  相似文献   
168.
Summary To investigate the dynamics of the winter flock patch exploitation, feeding experiments were performed with 140 semi-tame, free-roaming greylag geese (Anser anser). Three different initial densities of barley were offered on a 50-m2 patch: low (1600 grains/m2), intermediate (3300/m2) and high (I 1500/m2). Goose numbers on the patch, peck rates, and frequencies of agonistic encounters and of alert postures were observed by scanning the flock and in focal individuals. At low and intermediate initial food densities, peck rates decreased with food density, whereas at high food density, peck rates decreased only slightly over the feeding bout. Agonistic interactions increased as food decreased. A switch from exploitation to interference competition occurred at a threshold of approximately 900 remaining grains per square meter. With high initial food density, agonistic encounters began to increase gradually after 20–30 min. The same general patterns were observed for frequency of alertness. Family members occupied the patch for the longest time periods. The family female and the offspring fed most intensely. The family gander however, fed significantly less but was more aggressive and vigilant than all other social categories. Solitary geese spent their time on the patch doing little else but feeding and were the first to leave. It seems that high-ranking families and low-ranking singles adopt different competitive strategies, the former being superior interference competitors whereas the latter are forced scramble competitors.This study is dedicated to the memory of Konrad Lorenz Correspondence to: K. Kotrschal  相似文献   
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