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61.
Manure amendment in agricultural practice can have a large effect on herbicide dissipation because the period of manure plowing is close to the period of herbicide application. In addition, manure amendment is among the frequently encountered options in ameliorating pesticide pollution. In this research, the dissipation of the herbicide pendimethalin was examined after amendment with two common green manures, Lupinus luteus (L) or Cosmos bipinnatus (C), for 110 days in pH 5.2 and 7.7 soils (Sankengtzu [Sk] and Erhlin [Eh] soil, respectively). The microbial activity and ecology changes were examined by using Biolog EcoPlate and denaturing gradient gel electrophoresis (DGGE). In Sk soil, the half-lives of pendimethalin with L, C, and blank treatment were 49.0, 54.9, and 62.2 days, respectively, whereas that in Eh soil they were 46.3, 52.6, and 34.8 days, respectively. Pendimethalin dissipated quickly in more neutral soil (Eh soil), but the addition of manure can only increase the dissipation rate in acidic soil (Sk soil), indicating that the amendment of manures exerted different effect in pendimethalin dissipation rates in different pH soils. The application of pendimethalin and/or manure altered the microbial community activity after 24 h of incubation. After 110 days, the microbial community activities in green manure–amended soil were more similar to that with blank than pendimethalin treatment in both types of soils. In comparison with treatment C, microbial communities were more similar between treatment L and blank, indicating the superior effect over pendimethalin on microbial communities when applying Lupinus luteus. The research showed that the application of herbicide pendimethalin changed soil microbial community, and the amendment of manures exerted different effect in pendimethalin dissipation rates in different pH soils. It is assumed that the change in dissipation rates was originated from the microbial community change after different manure amendment.  相似文献   
62.
A field assessment of floor slipperiness in 10 fish stands in a fish market in Taiwan was conducted using both friction measurements and subjective ratings. The friction measurements were conducted using the Portable Skid Resistance Tester (PSRT). The subjective ratings of floor slipperiness of both the workers and the customers were collected. The friction measurement results showed that the sink areas had both the lowest friction values and subjective ratings. The overall friction measurement results and the subjective ratings were in fair agreement (r = 0.46 and ρ = 0.49). The customers perceived the walkways as somewhere between “very slippery” to “somewhat slippery” and the picking-up areas as “very slippery.” These were different from the perceptions of the workers where they perceived both areas as “somewhat slippery.”  相似文献   
63.
This study focuses on the use of indium gallium nitride multichip for ultra-high power light emitting diode (LED) heat transfer and thermal cooling analysis. This research approach is based on the multichip LED experimental study of aluminum extrusion heat sink and air-conditioning system-forced cooling approach. An investigation of heat transfer characteristics of the phenomenon of variation is conducted to improve performance and develop an LED system that can become a reference guideline for thermal design and assembly. This study’s package structure can use silicon substrate material and fill copper material to increase thermal conduction. An air-conditioning system bypass cooling approach is also used. This study aims to help to increase LED thermal cooling, long life, reliability, and reduce the optic lumen decay phenomenon in the future. Results are based on different power ratings that can be used to redefine LED classifications.  相似文献   
64.
Collocated comparisons for three PM2.5 monitors were conducted from June 2011 to May 2013 at an air monitoring station in the residential area of Fort McMurray, Alberta, Canada, a city located in the Athabasca Oil Sands Region. Extremely cold winters (down to approximately ?40°C) coupled with low PM2.5 concentrations present a challenge for continuous measurements. Both the tapered element oscillating microbalance (TEOM), operated at 40°C (i.e., TEOM40), and Synchronized Hybrid Ambient Real-time Particulate (SHARP, a Federal Equivalent Method [FEM]), were compared with a Partisol PM2.5 U.S. Federal Reference Method (FRM) sampler. While hourly TEOM40 PM2.5 were consistently ~20–50% lower than that of SHARP, no statistically significant differences were found between the 24-hr averages for FRM and SHARP. Orthogonal regression (OR) equations derived from FRM and TEOM40 were used to adjust the TEOM40 (i.e., TEOMadj) and improve its agreement with FRM, particularly for the cold season. The 12-year-long hourly TEOMadj measurements from 1999 to 2011 based on the OR equations between SHARP and TEOM40 were derived from the 2-year (2011–2013) collocated measurements. The trend analysis combining both TEOMadj and SHARP measurements showed a statistically significant decrease in PM2.5 concentrations with a seasonal slope of ?0.15 μg m?3 yr?1 from 1999 to 2014.Implications: Consistency in PM2.5 measurements are needed for trend analysis. Collocated comparison among the three PM2.5 monitors demonstrated the difference between FRM and TEOM, as well as between SHARP and TEOM. The orthogonal regressions equations can be applied to correct historical TEOM data to examine long-term trends within the network.  相似文献   
65.
A novel superhydrophobicelectroactive fluorinated polyimide (HEFPI) was first synthesized from aniline trimer and 4,4′-(Hexafluoroisopropylidene) diphthalic anhydride. The HEFPI could be fabricated as superhydrophobicfilm by replicated the surface of the Xanthosomasagittifolium leaves. The water contact angle of HEFPI film reaches as high as 157 ° and the superhydrophobic property of HEFPI could coat on cold-rolled steel (CRS) to prevent the metal corrosion. Electroactivity of EFPI was evaluated by performing electrochemical cyclic voltammetry study. Besides, redox catalytic capabilities of aniline trimer units existed in HEFPI main chain may induce the formation of passive metal oxide layers on the CRS electrode. The synergistic effects (hydrophobic property and passive metal oxide layers) make the HEFPI coating has great potential for advanced anticorrosion material.  相似文献   
66.
Environmental Science and Pollution Research - Human adenoviruses (HAdVs) are DNA viruses found in recreational water, such as water parks and swimming pools. Human adenovirus 41 (HAdV-41) is the...  相似文献   
67.
Aerosol from the burning two types of sandalwood-based incense, Hsing Shan and Lao Shan, was analyzed to characterize the chemical profile of total particulate matter emitted. The total particulate matter (PM) mass emission factors were 46.3 ± 2.68 mg g?1 of Hsing Shan incense and 43.7 ± 1.08 mg g?1 of Lao Shan incense. Chemical analysis of emissions from the two types of incense revealed that of the 25 components in four groups characterized, anhydrosugars formed the major group, at 46.7–52.2% w/w of the identified particulate and 1078.3–1169.8 μg g?1 of incense, followed by inorganic salts at 30.4–31.8% w/w of identified particulate and 681.6–734.0 μg g?1 of incense, carboxylic acids at 12.0–17.1% w/w of the identified particulate and 268.6–392.8 μg g?1 of incense, and sugar alcohols at 4.44–5.38% w/w of the identified particulate and 102.3–120.6 μg g?1 of incense. More anhydrosugars and sugar alcohols were emitted from Lao Shan incense than from Hsing Shan incense whereas more carboxylic acids and organic salts were emitted from Hsing Shan than from Lao Shan. These differences were due to structural and functional differences in the young sandalwood used to make Hsing Shan and the aged sandalwood used to make Lao Shan. The anhydrosugar levoglucosan, used as a marker of biomass burning, was always the most abundant species in emitted PM for both incenses (Lao Shan 21.7 mg g?1 of PM and Hsing Shan 18.7 mg g?1). K+ and Cl? were the second most abundant components (K+ and Cl? were summed), accounting for 10.6 mg g?1 of Hsing Shan PM and 9.85 mg g?1 of Lao Shan PM. The most abundant carboxylic acids in the emissions were formic, acetic, succinic, glutaric and phthalic acid. The latter is a fragrance ingredient and a potential health hazard and was twice as prevalent in Lao Shan emissions. Xylitol was the most prevalent of the sugar alcohols at 35.7–36.6% w/w of total identified sugar alcohols. These abundant species are potential markers for incense burning. K+, levoglucosan, mannosan and xylitol are already reported in discriminator ratios for wood burning and it is proposed here that these can and should also apply to incense burning. The calculated discriminator ratios for two types of incense burning reported here are 0.229–0.288 for K/Levo, 12.5–13.5 for Levo/Manno, and 21.5–23.7 for the novel discriminator ratio Levo/Xylitol.  相似文献   
68.
The main objective of this study was to monitor the volatile organic compounds (VOCs) in the stack gas released from organic chemical industrial plants to determine emission factors. Samples from 52 stacks, with or without air pollution control devices (APCDs), from seven industrial processes were taken and VOCs measured using U.S. Environmental Protection Agency (EPA) Method 18. These 7 processes, including 26 plants, were the manufacturers of acrylonitrile-butadiene-styrene (ABS), polyvinyl chloride (PVC), polystyrene (PS), acrylic resin (ACR), vinyl chloride (VC), para-terephthalic acid (PTA), and synthetic fiber (SYF). The results clearly indicate significant variations of emission factors among the various industrial processes, particularly emission factors for those without APCDs. As expected, those with APCDs yield much less emission factors. Regardless of those with or without APCDs, the order of manufacturing processes with regard to VOC emission factors is SYF > ABS > PS >ACR > PTA > PVC > VC. The emission factors for some processes also differ from those in EPA-42 data file. The VOC profiles further indicate that some VOCs are not listed in the U.S. VOC/Particulate Matter Speciation Data System (SPECIATE). The potential O3 formation is determined from the total amount of VOC emitted for each of seven processes. The resultant O3 yield varied from 0.22 (ACR) to 2.33 g O3 g(-1) VOC (PTA). The significance of this O3 yield is discussed.  相似文献   
69.
The purpose of this study is to establish a turbidity forecasting model as well as an early-warning system for turbidity management using rainfall records as the input variables. The Taipei Water Source Domain was employed as the study area, and ANOVA analysis showed that the accumulative rainfall records of 1-day Ping-lin, 2-day Ping-lin, 2-day Fei-tsui, 2-day Shi-san-gu, 2-day Tai-pin and 2-day Tong-hou were the six most significant parameters for downstream turbidity development. The artificial neural network model was developed and proven capable of predicting the turbidity concentration in the investigated catchment downstream area. The observed and model-calculated turbidity data were applied to developing the turbidity early-warning system. Using a previously determined turbidity as the threshold, the rainfall criterion, above which the downstream turbidity would possibly exceed this respective threshold turbidity, for the investigated rain gauge stations was determined. An exemplary illustration demonstrated the effectiveness of the proposed turbidity early-warning system as a precautionary alarm of possible significant increase of downstream turbidity. This study is the first report of the establishment of the turbidity early-warning system. Hopefully, this system can be applied to source water turbidity forecasting during storm events and provide a useful reference for subsequent adjustment of drinking water treatment operation.  相似文献   
70.
Urbanization and the subsequent changes in land use/cover inevitably influence the quality and even the quantity of stream water. This issue is widely studied through evaluations on land-use change scenarios or comparisons among historical patterns at the same watershed. However, observational stream discharge changes through urbanization gradient have rarely been discussed. In this study, we analyzed 5-year discharge data from 13 gauges in the Danshui River network with a wide range of urbanization gradient to explore the impacts on observational hydrological characteristics in individual catchments. The results reveal that stream discharge in pristine watersheds is characterized by a larger proportion of baseflow and is less fluctuating. When the forest coverage is <90%, the discharge fluctuation almost doubles. Meanwhile, the baseflow fraction decreases gradually with the increase of paddy area, which may concomitantly result from the increasing irrigation. Such a drop in baseflow may threaten the maintenance of the minimum flow required for the stream aquatic ecosystem. Furthermore, we simulated the stream discharges by TOPMODEL with blind land-use-independent parameters. The results show that the simulated discharges are satisfactory, particularly for the pristine catchments, but not as fitting for the paddy-intensive watersheds perhaps due to the unexpected irrigation. On the whole, the calibrated parameters are dependent with the landscape characteristics. The landscape-based parameter estimations can be applied to simulate discharge well, meaning the potential to assess the ungauged watersheds.  相似文献   
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