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61.
A female adult barred owl (Strix varia) had been hurt by a car. Its general status declined gradually within 2 wk with anorexia and inactivity. Necropsy examination revealed marked multifocal pale areas in liver, emaciation, and mild airsacculitis and pericarditis. Histopathologic examination revealed severe acute multifocal hepatic necrosis with numerous protozoal tachyzoites within necrotic foci and in the cytoplasm of hepatocytes and macrophages. These tachyzoites stained with an indirect immunohistochemistry method for Toxoplasma gondii antigens. This is the first reported case of hepatitis resulting from toxoplasmosis in a raptor. 相似文献
62.
This paper presents the analytical study of flat plate collector based on the computer‐based thermal models considering two different cases, case A (fully covered by glass) and case B (fully covered by photovoltaic (PV) module). These models are developed based on energy balance equations. An analytical expression for characteristic equation for photovoltaic–thermal flat plate collector has been derived as a function of design and climatic parameters. This paper shows the detailed analysis of energy, exergy and electrical energy by varying the number of collectors by considering four weather conditions (A, B, C and D type) for five different cities (New Delhi, Bangalore, Mumbai, Srinagar and Jodhpur) of India. It is observed that the collectors fully covered by PV module combine the production of hot water in addition to electricity generation and it is beneficial in terms of exergy, thermal energy and electrical energy gain. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
63.
A receiver structure based on maximum likelihood sequence estimation (MLSE) for receiving quaternary phase shift keyed signals over band-limited, nonlinear satellite channels, in the presence of additive downlink Gaussian noise, is derived. This work is an extension of work done by Mesiya et al. [2] for binary PSK transmission. Error performance of the receiver at low to moderate signal-to-noise ratios is estimated using computer simulation. For moderate to high signal-to-noise ratios, an upper bound on the probability of symbol error is obtained. A suboptimum receiver structure is then developed and its performance evaluated using computer simulation. It is shown that the performance of the suboptimum receiver is very close to that of the MLSE receiver. 相似文献
64.
K.A. Dubey C.V. Chaudhari S.K. Suman N. Raje R.K. Mondal V. Grover S. Murali Y.K. Bhardwaj L. Varshney 《Polymer Composites》2016,37(3):756-762
Flexible lead‐free high energy radiation shielding material was developed through internal compounding. Polymer‐filler interaction, crosslinking density, specific gravity, physicomechanical characteristics, percentage attenuation, and thermal stability of the crosslinked composites were estimated. It was found that even at very high filler loading composites can be crosslinked; however, the crosslinking density was composition dependent and was highest in 10–50 wt% loading range at 100 kGy and 200 kGy. The Nielsen model was applied to understand the micromechanics of the system. Attenuation of gamma radiation from Am241 was not affected by the crosslinking density. Thermal stability of the composites was found to be significantly affected with bismuth oxide loading. POLYM. COMPOS., 37:756–762, 2016. © 2014 Society of Plastics Engineers 相似文献
65.
Kadiyan Neha Chatterjee R. S. Pranjal Pranshu Agrawal Pankaj Jain S. K. Angurala M. L. Biyani A. K. Sati M. S. Kumar Dheeraj Bhardwaj Ashutosh Champati Ray P. K. 《Bulletin of Engineering Geology and the Environment》2021,80(4):3217-3231
Bulletin of Engineering Geology and the Environment - The present study identified groundwater depletion–induced land subsidence by spaceborne differential interferometric SAR (DInSAR)... 相似文献
66.
67.
Yong-Chul Jang Pradeep Jain Thabet Tolaymat Brajesh Dubey Shrawan Singh 《The Science of the total environment》2010,408(8):1878-1887
The chemical characterization of sediments accumulated in catch basins and stormwater ponds provides important information for assessing risks associated with management of these residuals upon removal of accumulated deposits in stormwater systems. In this study, over a period of 15 months, more than 150 residual samples were collected from 77 catch basin units and 22 stormwater ponds from 16 municipalities throughout the state of Florida. Concentrations (mg/kg) of metals and metalloids (arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and zinc) and trace organics (volatile organics, semi-volatile organics, herbicides, and pesticides) in the sediments were measured. In addition, the synthetic precipitation leaching procedure (SPLP) was utilized to evaluate pollutant leachability risk for a subset of the samples collected. Measured pollutant concentrations were compared to corresponding risk-based guidelines in Florida (i.e., Florida soil cleanup target levels) to assess potential human health risks of beneficial use of these residuals through land application. Leached concentrations were compared to risk-based water quality guidelines (i.e., Florida groundwater cleanup target levels) to examine the potential for groundwater contamination. Although several metals (arsenic, barium, chromium, copper, nickel, lead, and zinc) were routinely detected in the catch basin and stormwater pond sediments, their concentrations were generally lower than the Florida's risk-based cleanup target levels for soils. A small number of organochlorine compounds (e.g., 4,4′-DDE, 4,4′-DDT) were detected, but only in a limited number of the samples (less than 10%); leaching of trace organic pollutants above the Florida risk-based groundwater thresholds was rare. The results suggest that when land-applied or beneficially used, these residuals are not expected to pose a significant threat to human health or the environment and the results of this research will provide stormwater managers and environmental management authorities with a useful resource to examine proper disposal and beneficial use of catch basin and stormwater pond sediments. 相似文献
68.
Ishu Kansal Ashutosh Goel Dilshat U. Tulyaganov Raghu Raman Rajagopal José M.F. Ferreira 《Journal of the European Ceramic Society》2012,32(11):2739-2746
The influence of varying the CaO/MgO ratio on the structure and thermal properties of CaO–MgO–SiO2–P2O5–CaF2 glasses was studied in a series of eight glass compositions in the glass forming region of diopside (CaMgSi2O6)–fluorapatite [Ca5(PO4)3F]–wollastonite (CaSiO3) ternary system. The melt-quenched glasses were characterized for their structure by infrared spectroscopy (FTIR) and magic angle spinning (MAS)-nuclear magnetic resonance (NMR) spectroscopy. Silicon is predominantly present as Q2 (Si) species, while phosphorus tends to coordinate in orthophosphate environment. The sintering and crystallization parameters of the glasses were obtained from differential thermal analysis (DTA) while crystalline phase fractions in the sintered glass–ceramics were analyzed by X-ray diffraction adjoined with Rietveld refinement. Diopside, fluorapatite, wollastonite and pseudowollastonite crystallized as the main crystalline phases in all the glass–ceramics with their content varying with respect to variation in CaO/MgO ratio in glasses. The implications of structure and sintering behaviour of glasses on their bioactivity were discussed. 相似文献
69.
The protective potential of protective devices such as respirators, suits, gloves, and overboots is widely evaluated using the standard colorimetric test (spot disc breakthrough time test, also called SD BTT) involving sulfur mustard (SM) as the challenge chemical. The vesicant nature of SM makes the test inconvenient and poses stringent safety demands. Moreover, such tests are allowed only at a limited number of facilities, causing delay in product development and supply. This prompted the present study on the search for suitable SM simulant responsive to SD BTT test. The diffusivities at BTT (DBTT) of 10 commercially available thiocompounds through butyl rubber (IIR) were compared vis‐a‐vis DBTT of SM. For three representative thiocompounds, namely methyl (phenyl thio)acetate, 2‐chloroethyl phenyl sulfide (2‐CEPS) and phenyl‐n‐propyl sulfide (PNPS), the transport parameters through IIR were obtained. PNPS and 2‐CEPS were further compared with respect to DBTT in elastomers such as IIR, ethylene–propylene–diene methylene rubber, polydimethylsiloxane, nitrile rubber, polybutadiene, and natural rubber. 2‐CEPS showed generally same order of DBTT as SM implying its potential use as a simulant. The transport parameters for various 2‐CEPS/elastomer systems were also determined. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
70.