Traffic-related air pollution (TRAP), including particulate matter (PM) in respirable coarse and fine size fractions (PM10 and PM2.5), is known to have exposure effects on human health and environment. Real-time PM10 and PM2.5 concentrations were collected from the study locations in Bangkok, Thailand, using TSI AM510 particle counters. Temperature and % relative humidity (%RH) were also collected. Data were compared to data from the closest station of the Pollution Control Department (PCD), Thailand. Real-time mean concentration varied from 86 to 1107 µg/m3 (PM10) and varied from 25 to 664 µg/m3 (PM2.5). In addition, real-time mean PM10 (223.1 µg/m3) was nearly four times greater than that measured by the PCD station, 60 µg/m3. Temperature and %RH from real-time air monitoring and PCD station were comparable. In each study location (five locations, two in morning and afternoon/evening), there were significant positive correlations between PM10 and PM2.5 concentrations and significant negative correlations between temperature and RH%. Results suggested that outdoor TRAP via measured real-time PM concentrations were more realistic exposure concentration estimates among street vendors as related to respiratory and other symptoms than data obtained from PCD station. Nevertheless, PM10 as measured by the PCD station might be a reasonable surrogate for estimated outdoor PM2.5 exposure. 相似文献
A vertical flat-plate photobioreactor was developed for the outdoor culture of microalgae using sunlight as the light source. The ability for biomass production and CO2 fixation was evaluated by using a cyanobacterium, Synechocystis aquatilis SI-2. The average areal productivity was 31 g biomass m–2 d–1, which corresponded to a CO2 fixation rate of 51 g CO2 m–2 d–1, sustainable in the northern region of Japan during the winter time (January and February). The relationships between the efficiency of solar energy utilization of the reactor and its effect factors (cell concentration and irradiation) were investigated. 相似文献
1. 1. Intensities of ultraviolet rays (UV) from every direction and the amount of UV absorbed by each body part was measured in four situations (track, beach, golf course and skiing slope).
2. 2. The intensity of UV was measured by a portable UV meter and the amount of UV absorbed by every body part was measured with a UV irradiation energy measurement label.
3. 3. The intensity of UV was strong from S45° and SE45° in all cases. On snow, the intensity of UV from every direction was stronger than in other situations, it was especially strong in reflection from below and from the north. The UV reflection from the sand was slightly larger than that from mud and grass.
4. 4. The experimental day's weather was fine and occasionally cloudy during golf, beach activity and gate-ball, and clear during skiing.
5. 5. The UV deal of a horizontal plane was 135, 98, 156 and 120 kJ/m2/h at golf, beach activity, gate-ball and skiing, respectively.
6. 6. This study suggests that players should be concerned with the prevention of UV radiation during sporting activity.
Cells of Chlorella regularis (Artari) Oltmanns (S-50) were grown under solar radiation in Tokyo, using a newly constructed outdoor culture system. The maximum specific growth rate (log2 unit h−1) was about 0.3, which was a little lower than the highest value reported using artificial light in the laboratory. The near ultraviolet light, consisting mostly of UV-A, inhibited the growth from 10 to 40% in summer mornings; the inhibition was not significant in the afternoon. The percentage inhibition was correlated with the total dose of the ultraviolet radiation. 相似文献
Prevalence of different species of Penicillium and their concentrations per cubic meter of air were evaluated with the use of Hi-Air sampler system Mark II (Hi-Media Laboratories Ltd., India) in the air of homes (bed-rooms) at four different sites in Nagpur. At each of these sites, air sampling was done fortnightly in triplicate for 2 years duration from June 2000 to May 2002. The sampling was also done in triplicate for the outdoor air in the vicinity of each home on the same day immediately after the indoor sampling was over. The mean concentration of Penicillium colony forming units at four different sites in the indoor air was 32, 46.9, 35 and 35.4 CFU/m3, respectively, whereas in the outdoor air at these same four sites, the mean concentration was 24, 28, 25 and 25.8 CFU/m3 respectively. The Penicillium concentration in the indoor air was found to be higher in winter than in other seasons (ANOVA, p < 0.05). Concentration of Penicillium spp. in intramural environment was always higher than that in extramural environment. Statistically significant difference existed between intramural and extramural environments at all the sites, with maximum difference at a site, which is old crowded area of the city. During the 2-years investigations, 11 species of Penicillium were isolated from the indoor air while nine species were isolated from the air outside the homes. The dominant species of Penicillium in indoor as well as outdoor air were P. citrinum (33.78 and 32.81), P. oxalicum (19.70 and 22.60), and P. chrysogenum (17.64 and 14.50). The percentage of the Penicillium in the indoor air was 10.70 while it was 8.36 in outdoor air. Indoor air showed the presence of P. glaber and P. sclerotiorum, which were absent in the outdoor air. 相似文献
Chlorella zofingiensis was grown in semi-continuous culture in an outdoor enclosed tubular photobioreactor. At the quasi-steady
state, the response of the culture to changes in photosynthetically active radiance (PAR) was studied by following closely
the dissolved O2 concentration,biomass concentration and the carbohydrate and protein content of the biomass. Generally, O2 production and the output of carbon and nitrogen of the biomass showed a linear correlation with incident PAR, suggesting
that the cultures were light-limited. Photoinhibition was not observed in high light adapted cultures (on a sunny day), but
was observed in shade adapted cultures(cloudy days) when there was a sudden four-fold increase in PAR. The output rate of
biomass nitrogen observed on sunny days was, however, lower than that measured on cloudy days. On sunny days, a rapid increase
in the C/N ratio of the biomass was seen. We attribute the increase in C/N ratio on sunny days to a slower response of protein
synthesis to big increases in PAR, compared to carbohydrate synthesis. The possible influence of this C and N response pattern
on the productivity of outdoor algal cultures is discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
The performance ofNodularia harveyana, a N2-fixing cyanobacterium isolated from seawater, has been studied outdoors in two different culture systems: open pond (OP) and tubular photobioreactor (TPR). The productivity in both devices was influenced by areal density. The maximum yield obtained was 12.0 g (d.wt) m–2 day–1 in OP and 14.0 g (d.wt) m–2 day–1 in TPR in August, corresponding to the highest solar radiation received. In a month-long experiment with the cyanobacterium cultivated in TPR at high circulation speed, a net increase in productivity was obtained over that at low circulation speed. The influence of temperature on the productivity of the cultures grown in open ponds and tubular photobioreactors has been investigated. The higher productivity obtained in TPR compared to OP was attributed to its better controlled temperature conditions. In outdoor culture the maximum nitrogenase activity did not coincide with the maximum light intensity, but occurred in early afternoon. The amount of carbohydrate accumulated during the day probably influenced the rate of dark nitrogenase activity and its duration in the night. 相似文献
The relative efficacy of a mechanical (Prokopack) collection method vs. manual aspiration in the collection of resting mosquitoes was evaluated in northern Tanzania before and after an intervention using indoor residual spraying and longlasting insecticide‐treated nets. In smoke‐free houses mosquitoes were collected from the roof and walls, but in smoky houses mosquitoes were found predominantly on the walls. Anopheles gambiae (Diptera: Culicidae) constituted 97.7% of the 312 An. gambiae complex specimens identified before but only 19.3% of the 183 identified after the intervention. A single sampling with the Prokopack collected a third of the available insects. Anopheles gambiae completed its gonotrophic development indoors, whereas Anopheles arabiensis did so outdoors. In both species gonotrophic development took 2 days. Most unfed resting An. arabiensis collected outdoors were virgins, whereas the majority of engorged insects were parous (with well‐contracted sacs). Daily survival was estimated to be 80.0%. Only 9.4% of the engorged An. arabiensis collected outdoors and 47.1% of those collected indoors had fed on humans. Using the Prokopack sampler is more efficient than manual methods for the collection of resting mosquitoes. Malaria transmission may have been affected by a change in vector composition resulting from a change in feeding, rather than reduced survival. Monitoring the proportions of members of the An. gambiae complex may provide signals of an impending breakdown in control. 相似文献