Enhanced photocatalytic activity of fish scale loaded TiO2 composites under solar light irradiation

Fish scale (FS) loaded TiO₂ composites were investigated as photocatalysts in degradation of Methyl Orange under solar light irradiation. Composites were prepared through sol-gel method by varying mass ratio of TiO₂/FS at 90:10, 70:30 and 50:50, respectively. The catalysts prepared in this study were characterized by using XRD, SEM, FT-IR and nitrogen sorption. The effects of solar irradiation, mass ratio of TiO₂/FS composites, irradiation time and catalyst loadings were studied. Synergistic effect was found in TiO₂/FS of 90:10 composite which performed higher photocatalytic degradation than synthesized TiO₂ under solar light irradiation. However, further increasing fish scale content in the composites reduced the photocatalytic activity drastically. Under solar light irradiation, all the catalysts in this study exhibited photocatalytic activity, except TiO₂/FS of 50:50 composite that only acted as a weak biosorbent without performing any photocatalytic property. Photocatalytic degradation increased with increasing catalyst loading and irradiation time but decreased with increased of initial dye concentration.     

Strategic 3-hydroxy-2-butanone release in the dominant male lobster cockroach, <Emphasis Type="Italic">Nauphoeta cinerea</Emphasis>

In the lobster cockroach Nauphoete cinerea, the dominant–subordinate hierarchy formed via the agonistic interactions is unstable, and changes in rank order are common. Our previous results showed that in the first encounter fight during initial rank formation, microgram levels of 3H-2B are released by the aggressive posture (AP)-adopting dominant male. In the present study, the pattern of daily pheromone (3H-2B) release during the domination period and on the day of rank switch, rank duration, and rank switch frequency were investigated in three-male groups and six-male groups to examine the effect of higher frequency of agonistic encounters. The results showed that, in the three-male groups (50-day observation period), daily 3H-2B release rate was not constant, but fluctuated, the average duration of dominant rank was 16.6 ± 2.0 days, rank switch occurred in 58.8% of groups, and the frequency of rank switching (average number of rank switches/group/50 days) was 1.4 ± 0.2. For the six-male groups (30-day observation period), the daily 3H-2B release rate also fluctuated, but the duration of dominant rank was significantly shorter at 4.2 ± 0.6 days, rank switch occurred in 100% of groups, and the frequency of rank switching (average number of rank switches/group/30 days) was significantly higher at 6.9 ± 0.6. The results for both sets of male groups showed that as a new rank formed (either on the first encounter day or on the day of rank switching), the dominant status was significantly associated with a higher 3H-2B release rate. In the animal kingdom, fighting usually involves communication or the exchange of signals, and the results of this study indicated that the fluctuating daily 3H-2B release rate adopted by the dominants is a kind of strategic release and the 3H-2B release rate is a signal used to determine dominance.     

Weekly periodicities of meteorological variables and their possible association with aerosols in Korea

The weekly periodicities in meteorological variables and its association with aerosols in Korea are investigated using long-term surface measurements of meteorology (1975–2005) and aerosols (1999–2005). Through an analysis of the annual (and/or seasonal) values averaged over 10 stations, we identified distinct weekly periodicities in the daily minimum temperature (T_min), diurnal temperature range (DTR), cloud fraction, and solar insolation, although they have different characteristics from each other. The weekly association among variables is discussed in this study. Positive anomalies of the cloud fraction and T_min and negative anomalies of solar insolation and DTR are seen for the second half of the week and the reverse for the first half of the week, i.e., more cloudiness and less insolation for Wednesday?Thursday and less cloudiness and more insolation for Monday?Tuesday. Furthermore, seasonal dependence of weekly anomalies shows that the weekly periodicities are enhanced especially in autumn, more than 2–3 times as great as those of the annual mean. The weekly cycles in such variables are most likely driven by changes in cloud fraction, possibly through aerosol–cloud interactions induced by aerosol variations between working weekdays and Sunday, which are clearly identified in PM10 weekly cycles. This study also suggests that the weekly periodicities in meteorological variables are possibly associated with long-range transport of weekly periodicities, as well as aerosol–cloud-precipitation interactions over the region.     

Estimating bulk optical properties of aerosols over the western North Pacific by using MODIS and CERES measurements

Over the western North Pacific, a large amount of land aerosols from Asian-Pacific countries is transported by the prevailing westerlies. This transport makes the radiative characteristics of these aerosols diverse, particularly when one compares those characteristics over the coastal sea with those over the open sea. In this paper we discuss a method that uses satellite data to obtain the single-scattering albedo (ω) and asymmetry factor (g) of atmospheric aerosols for two large-scale subdivisions—the coastal sea (within 250 km from the coast) and the open sea (the remaining area)—over the western North Pacific (110°E–180°, 20°N–50°N). Our estimation method uses satellite measurements, obtained over a six-year period (2000–2005), of aerosol optical depth (AOD) and shortwave fluxes at both the surface and the top of the atmosphere (TOA); the measurements are obtained using the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Clouds and the Earth's Radiant Energy System (CERES). For the two subdivisions, the estimated annual means of (ω,g) at 630 nm are significantly different: (0.94, 0.65) over the coastal sea and (0.97, 0.70) over the open sea. From a quantitative viewpoint, this result indicates that in comparison with aerosols over the open sea, those over the coastal sea show greater absorption and lesser forward scattering of solar radiation. The estimated optical properties are responsible for the aerosol surface cooling observed by MODIS and CERES, which is approximately 138 and 108 W m⁻² per AOD over the coastal sea and open sea, respectively.     

Fluorinated alkyl compounds including long chain carboxylic acids in wild bird livers from Japan

A wide range of fluorinated alkyl compounds (FACs) has been reported in wildlife in various locations in the world. However, such information regarding Japanese wildlife is rarely found. In the present study, we investigated the occurrence of 21 FACs, including perfluorinated alkyl sulfonates (PFASs), perfluorinated carboxylates (PFCAs), and fluorotelomer acids, in the livers of 10 wild bird species from two regions in northern Japan. To avoid interferences, FACs were quantified by a recently developed method using acetonitrile and solid-phase extraction followed by an ion exchange HPLC column separation. Apart from perfluorooctane sulfonate (PFOS), which was found at the highest levels of all the compounds detected, several long chain perfluorinated carboxylates (PFCAs) from C8 to C16, particularly perfluorotetradecanoic acid (PFTeDA) and perfluorohexadecanoic acid (PFHxDA), were detected for the first time. Additionally, 7:3 FTCA, a fluorotelomer acid, was also detected in most swan livers from Miyagi prefecture and all the birds from Tochigi prefecture. However, none of the sulfonamides and unsaturated telomer acids were detected in any species. Swans seem to be the least exposed wild birds to FACs among the investigated birds, signifying that feeding habits may reflect FAC accumulation in wild birds. The highest total concentration of detected FACs was 405 ng g⁻¹ wet wt., which was found in a Japanese sparrowhawk, indicating that the top predatory wild birds can accumulate several long chain carboxylic acids. However, the current FAC concentrations found in livers may suggest that these compounds alone would not cause a severe toxic effect in these species.     

Gaseous and particulate polycyclic aromatic hydrocarbons (PAHs) emissions from commercial restaurants in Hong Kong

Commercial cooking emissions are important air pollution sources in a heavily urbanized city. Exhaust samples were collected in six representative commercial kitchens including Chinese restaurants, Western restaurants, and Western fast-food restaurants in Hong Kong during peak lunch hours. Both gaseous and particulate emissions were evaluated. Eight gaseous and twenty-two particulate polycyclic aromatic hydrocarbons (PAHs) were quantified in this study. In the gaseous phase, naphthalene (67-89%) was the most abundant PAH in all of the exhaust samples. The contribution of acenaphthylene in the gaseous phase was significantly higher in emissions from the Chinese restaurants, whereas fluorene was higher in emissions from the Western cooking style restaurants (i.e., Western restaurants and Western fast-food restaurants). Pyrene is the most abundant particulate PAH in the Chinese restaurants (14-49%) while its contribution was much lower in the Western cooking style restaurants (10-22%). Controlled cooking conditions were monitored in a staff canteen to compare the emissions from several different local cooking styles, including deep frying, steaming, and mixed cooking styles (combination of steaming and frying). Deep frying produced the highest amount of total gaseous PAHs, 6 times higher than the steaming. However, steaming produced the highest particulate emissions. The estimated annual gaseous PAH emissions for the Chinese restaurants, Western restaurants, and Western fast-food restaurants were 255, 173, and 20.2 t y(-1) whereas 252, 1.9, and 0.4 t y(-1) were estimated for particulate phase PAH emissions. The study provides useful information and estimates for PAH emissions from commercial cooking exhaust in Hong Kong.     

Use of a GIS-based hybrid artificial neural network to prioritize the order of pipe replacement in a water distribution network

A methodology based on the integration of a seismic-based artificial neural network (ANN) model and a geographic information system (GIS) to assess water leakage and to prioritize pipeline replacement is developed in this work. Qualified pipeline break-event data derived from the Taiwan Water Corporation Pipeline Leakage Repair Management System were analyzed. “Pipe diameter,” “pipe material,” and “the number of magnitude-3^?+? earthquakes” were employed as the input factors of ANN, while “the number of monthly breaks” was used for the prediction output. This study is the first attempt to manipulate earthquake data in the break-event ANN prediction model. Spatial distribution of the pipeline break-event data was analyzed and visualized by GIS. Through this, the users can swiftly figure out the hotspots of the leakage areas. A northeastern township in Taiwan, frequently affected by earthquakes, is chosen as the case study. Compared to the traditional processes for determining the priorities of pipeline replacement, the methodology developed is more effective and efficient. Likewise, the methodology can overcome the difficulty of prioritizing pipeline replacement even in situations where the break-event records are unavailable.     

Atmospheric Aerosol over a Southeastern Region of Texas: Chemical Composition and Possible Sources

Speciated samples of PM_2.5 were collected at a site in Jefferson County, Texas by US EPA (Environmental Protection Agency) from July of 2003 to August of 2005. A total of 269 samples with 52 species were measured; however, 22 species were excluded in this study because of too many below-detection-limit data. The data set was analyzed by positive matrix factorization (PMF) to infer the sources of PM observed at the site. The analysis identified ten sources: sulfate-rich secondary aerosol I (35.9%), sulfate-rich secondary aerosol II (21.0%), cement/carbon-rich (11.7%), wood smoke (8.8%), metal processing (6.3%), motor vehicle/road dust (5.7%), nitrate-rich secondary aerosol (3.3%), soil (3.2%), sea salt (2.6%), and chloride depleted marine aerosol (1.6%). Sulfate and nitrate mainly exist as salts. The two sulfate-rich secondary aerosols account for almost 57% of the PM_2.5 mass concentration. The factor containing highest concentrations of Cl and Na was attributed to sea salt due to the proximity of the monitoring site to the Gulf of Mexico. The chloride depleted marine aerosol was related to the sea salt aerosol. Cement/carbon-rich, wood smoke, metal processing, and motor vehicle/road dust factor were likely to be the local sources.     

Analysis of multi-temporal landsat satellite images for monitoring land surface temperature of municipal solid waste disposal sites

This studypresents a remote sensing application of using time series Landsat satellite images for monitoring the Trail Road and Nepean municipal solid waste (MSW) disposal sites in Ottawa, Ontario, Canada. Currently, the Trail Road landfill is in operation; however, during the 1960s and 1980s, the city relied heavily on the Nepean landfill. More than 400 Landsat satellite images were acquired from the US Geological Survey (USGS) data archive between 1984 and 2011. Atmospheric correction was conducted on the Landsat images in order to derive the landfill sites’ land surface temperature (LST). The findings unveil that the average LST of the landfill was always higher than the immediate surrounding vegetation and air temperature by 4 to 10 °C and 5 to 11.5 °C, respectively. During the summer, higher differences of LST between the landfill and its immediate surrounding vegetation were apparent, while minima were mostly found in fall. Furthermore, there was no significant temperature difference between the Nepean landfill (closed) and the Trail Road landfill (active) from 1984 to 2007. Nevertheless, the LST of the Trail Road landfill was much higher than the Nepean by 15 to 20 °C after 2007. This is mainly due to the construction and dumping activities (which were found to be active within the past few years) associated with the expansion of the Trail Road landfill. The study demonstrates that the use of the Landsat data archive can provide additional and viable information for the aid of MSW disposal site monitoring.     

对美国格林威治湾底栖动物造成危害的潜在胁迫因子的诊断

格林威治湾是纳拉甘西特湾一处受到多种影响因子作用的城市化形成港湾。本研究鉴定了对于格林威治湾底栖动物的重要影响因素。首先利用现存数据与信息来验证水体受损情况。其次确定了影响来源,影响因素和具体影响的存在。继而探究了来源,影响因素和具体影响之间的关系。这使我们能够鉴定出最可能危害水体的影响因素。本研究评估了化学制品、营养物质和悬浮沉积物3类污染物。这种证据权重的方法表明格林威治湾主要受到富营养化相关的影响因素危害。格林威治湾的沉积物富含碳,低溶解氧浓度的情况十分常见,尤其在格林威治湾西部。底栖生物群落出现发育不良的情况,与在氧气不足情况下的预测结果吻合。尽管我们的分析表明环境中的污染物浓度可能导致有害结果的出现,我们并未在结果中检出毒性。这是由于沉积物中存在大量的有机物,这些有机物限制了污染物的生物可利用性。我们的分析还表明悬浮沉积物的影响对于湾区的大部分区域而言几乎不存在。本分析展示了诊断法步骤可以用于组织和评估影响格林威治湾生态健康的潜在影响因素。诊断法步骤对于管理受到多重因素影响的水体非常有用。
精选自Marguerite Pelletier, Kay Ho, Mark Cantwell, Monique Perron, Kenneth Rocha, Robert M. Burgess, Roxanne Johnson, Kenneth Perez, John Cardin, Michael A. Charpentier. Diagnosis of potential stressors adversely affecting benthic invertebrate communities in Greenwich Bay, Rhode Island, USA. Environmental Toxicology and Chemistry: Volume 36, Issue 2, pages 449–462, July 2017. DOI: 10.1002/etc.3562
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3562/full