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71.
In this study, a method which is environmentally sound, time and energy efficient has been used for recovery of indium from used liquid crystal display (LCD) panels. In this method, indium tin oxide (ITO) glass was crushed to micron size particles in seconds via high energy ball milling (HEBM). The parameters affecting the amount of dissolved indium such as milling time, particle size, effect time of acid solution, amount of HCl in the acid solution were tried to be optimized. The results show that by crushing ITO glass to micron size particles by HEBM, it is possible to extract higher amount of indium at room temperature than that by conventional methods using only conventional shredding machines. In this study, 86% of indium which exists in raw materials was recovered about in a very short time.  相似文献   
72.
Continuous measurements of particle number concentrations were performed in Rochester, NY, and Toronto, Ontario, Canada during the 2003 calendar year. Strong seasonal dependency in particle number concentration was observed at two sites. The average number concentration of ambient particles was 9670 +/- 6960 cm(-3) in Rochester, whereas in Toronto the average number of particles was 28,010 +/- 13,350 cm(-3). The particle number concentrations were higher in winter months than in summer months by a factor of 1.5 in Rochester and 1.6 in Toronto. In general, there were also distinct diurnal variations of aerosol number concentration. The highest weekdays/weekends ratio of number concentration was typically observed during the rush-hour period in winter months with a ratio of 2.1 in Rochester and 2.0 in Toronto. The correlation in the total particle number concentrations between the two urban sites was stronger in winter because of the common urban traffic patterns, but weaker in summer because of local sulfur dioxide (SO2)-related particle formation events in Rochester in the summer. Strong morning particle formation events were frequently observed during colder winter months. Good correlations between particle number and carbon monoxide (CO) as well as temperature suggested that motorvehicle emissions lead to the formation of new particles as the exhaust mixes with the cold air. Regional nucleation and growth events frequently occurred in April. Local SO2-related particle formation events most frequently occurred in August. SO2 and UV-B were highly correlated with particle concentration, suggesting a high association of photochemical processes with these local events. A high directionality in a northerly direction was observed for particle number and SO2, indicating the influence of point sources located north of Rochester.  相似文献   
73.
Abstract: Mid‐range streamflow predictions are extremely important for managing water resources. The ability to provide mid‐range (three to six months) streamflow forecasts enables considerable improvements in water resources system operations. The skill and economic value of such forecasts are of great interest. In this research, output from a general circulation model (GCM) is used to generate hydrologic input for mid‐range streamflow forecasts. Statistical procedures including: (1) transformation, (2) correction, (3) observation of ensemble average, (4) improvement of forecast, and (5) forecast skill test are conducted to minimize the error associated with different spatial resolution between the large‐scale GCM and the finer‐scale hydrologic model and to improve forecast skills. The accuracy of a streamflow forecast generated using a hydrologic model forced with GCM output for the basin was evaluated by forecast skill scores associated with the set of streamflow forecast values in a categorical forecast. Despite the generally low forecast skill score exhibited by the climate forecasting approach, precipitation forecast skill clearly improves when a conditional forecast is performed during the East Asia summer monsoon, June through August.  相似文献   
74.
Congenital epulis is a benign intraoral tumor that has rarely been diagnosed prenatally. We report a fetus with congenital epulis diagnosed by three-dimensional (3-D) ultrasound and fetal magnetic resonance imaging (MRI) at 35 weeks' gestation. We show an image of congenital epulis using a new ultrasound technique, the 3-D multislice view, which shows images similar to CT or MRI. This is a short case report of congenital epulis diagnosed prenatally by 3-D ultrasound using multislice view and MRI. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
75.
The Triad Approach was field‐tested to determine if characterization objectives could be met for a brownfields property that had been identified as a future elementary school site. The new school is in response to a New Jersey Supreme Court ruling (the Abbott decision) that directed the state of New Jersey to fund school construction in poorer districts to expand physical facilities to relieve overcrowding. The Triad Approach is promoted by the United States Environmental Protection Agency as a process that has the potential to improve the timeliness and efficiency of site characterization, and the New Jersey Department of Environmental Protection (NJDEP) recently issued a policy statement supporting its potential. Aggressive school construction deadlines are contingent on property acquisitions that are relatively faster than the traditional investigatory process. In addition, given the future sensitive population, the investigations must be thorough. This case study is among the first studies to document the use of the Triad Approach for a future school site. The Triad Approach was used to define site conditions for six areas of concern in a two‐month time frame (from the start of the planning process to completed investigation). © 2004 Wiley Periodicals, Inc.  相似文献   
76.
77.
The aim of this study was to isolate and characterize Bacillus cereus bacteriophages of various origins. Twenty-seven bacteriophages against B. cereus were isolated from various Korean traditional fermented foods and soils. Plaque size, transmission electron microscopy, virulence profile, and in vitro lytic activity of bacteriophage isolates were examined. Transmission electron microscopy confirmed B. cereus bacteriophages belonging to the family Siphoviridae. Among B. cereus bacteriophages with broad host range, 18 isolates (66.7%) did not harbor any B. cereus virulence factors. Among them, bacteriophage strain CAU150036, CAU150038, CAU150058, CAU150064, CAU150065, and CAU150066 effectively inhibited B. cereus in vitro within 1 h. Therefore, they are considered potential candidates for controlling the contamination of B. cereus in food or other applications.  相似文献   
78.
Noroviruses are major causative pathogen of nonbacterial acute gastroenteritis worldwide. Of the seven genogroups of noroviruses suggested recently, genogroup II genotype 4 (GII.4) had been the most common genotype identified in hospitalized patients in the last few decades. However, since the latter half of 2014, new variants of GII.17 have been reported as the main causes of outbreaks over GII.4 in East Asia and have also occurred in America and Europe. In this study, we monitored norovirus GII in coastal streams at South Gyeongsang province and South Jeolla province of South Korea from March 2015 to May 2016. Norovirus GII.17 capsid sequences were predominantly detected until September 2015 in water samples. However, we found that the number of positive cases of the norovirus GII.4 Sydney 2012 capsid sequence has been increasing since December 2015, overtaking that of GII.17 in 2016. The RdRp genotype of this predominant GII.4 variant in 2016 was identified as GII.P16. The emergence and predominance of the GII.4 pandemic capsid sequence harboring a different RdRp genotype suggested the potential for a future pandemic.  相似文献   
79.
Indoor air quality (IAQ) directly affects the health of occupants. Household manufacturing equipment (HME) used for hobbies or educational purposes is a new and unexplored source of air pollution. In this study, we evaluated the characteristics of particulate and gaseous pollutants produced by a household laser processing equipment (HLPE). Various target materials were tested using a commercial HLPE under various operating conditions of laser power and sheath air flow rate. The mode diameters of the emitted particles gradually decreased as laser power increased, while the particle number concentration (PNC) and particle emission rate (PER) increased. In addition, as the sheath air flow rate quadrupled from 10 to 40 L/min, the mode diameter of the emitted particles decreased by nearly 25%, but the effect on the PNC was insignificant. When the laser induced the target materials at 53 mW, the mode diameters of particles were <150 nm, and PNCs were >2.0 × 104 particles/cm3. Particularly, analyses of sampled aerosols indicated that harmful substances such as sulfur and barium were present in particles emitted from leather. The carcinogenic gaseous pollutants such as acrylonitrile, acetaldehyde, 1,3-butadiene, benzene, and C8 aromatics (ethylbenzene) were emitted from all target materials. In an actual indoor environment, the PNC of inhalable ultrafine particles (UFPs) was >5 × 104 particles/cm3 during 30 min of HLPE operation. Our results suggest that more meticulous control methods are needed, including the use of less harmful target materials along with filters or adsorbents that prevent emission of pollutants.  相似文献   
80.
The diurnal vertical migration of Cochlodinium polykrikoides (C. polykrikoides), which caused a red tide in the Korean coastal waters of the East Sea/Sea of Japan in September 2003, was examined by determining the time-dependent changes in the density of living cells in relation to the depth of the water column. The ascent of this species into the surface layer (depth of water 2 m) occurred during 1400-1500. The descent started at 1600 and a high distribution rate (86%) at 15-20 m was observed at 0300. During the ascent, the cells were widely distributed at each depth level from 0600 hr and at 0800-1100, the cells were primarily distributed in the middle layer (0-6 m). The concentration of dissolved inorganic nitrogen was generally < or = 2.86 micromol l(-1), but at 1400-1500, the concentration in the surface layer reduced to < or = 0.14 micromol l(-1). Moreover, the concentration gradually increased as the depth increased to > or = 5 m. These results showed that the nutrient-consumption rate associated with the proliferation of C. polykrikoides during a red tide is more influenced by the inorganic-nitrogen resources ratherthan the inorganic-phosphorus compounds.  相似文献   
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