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Effect of Freezing and Thawing on the Histology and Ultrastructure of Buffalo Muscle
Sen, A.R.,Sharma, N. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.9
Histology and transmission electron microscopy studies were carried out on buffalo muscles that were subjected to repeated freeze-thaw cycles at -10 and $-18^{\circ}C$. In the first freeze thaw cycle ($-10^{\circ}C$) structures of muscle showed slight change and closely resembled to those of normal muscle. There were frequent gaps in the half way across the fibres and some cracks in individual fibre were also noticed in second freeze thaw cycle. In the muscle frozen at $-18^{\circ}C$, more pronounced shrinkage with extensive damage of fibres with tearing was observed. The interfibrillar gaps were wider, shrinkage and tearing of the fibres were more distinct after second freeze-thaw cycle. After the second cycle, the interior portion showed large scale degradation of the ultrastructure. Our studies of buffalo muscle showed that under the proper condition, little structural damage takes place in the meat histology and ultrastructure under repeated freeze-thaw conditions. This study adds continued weight to the evidence that limited freeze-thaw cycles will not deteriorate the quality of meat.
Determination of antibiotics by SPE-LC-MS/MS in wastewater and risk assessment
Aydin, Senar,Aydin, Mehmet E.,Ulvi, Arzu,Kilic, Havva Techno-Press 2018 Advances in environmental research Vol.7 No.3
In this study, conditions of solid phase extraction (SPE) for determination of some antibiotics such as trimethoprim, oxytetracycline, erythromycin, clarithromycin, azythromycin, doxycycline, sulfamethazine, ciprofloxacin, chlortetracycline, sulfamethoxazole in wastewaters were optimized. After the optimum volume and pH of the sample were determined, the effect of the concentration of the compounds and matrix were investigated. The highest recovery rates for antibiotic compounds were determined between 82% and 105% in 200 mL sample volume and pH 2.5. Then, antibiotic compounds were investigated in influent and effluent samples taken from Konya Urban Wastewater Treatment Plant. The concentration of the antibiotics was detected range of 0.11-101 ng/L in influent waters and <dl-288 ng/L in effluent samples in wastewater treatment plant. Hazard quotients (HQs) of antibiotic compounds determined in WWTP effluents to evaluate the risk towards different aquatic organisms (algae, Daphnia magna and fish) were determined. Azythromycin for fish and erythromycin, sulfamethoxazole, ciprofloxacin, clarithromycin for algae posed a moderate risk while azythromycin, ciprofloxacin, clarithromycin, oxytetracycline posed a high risk for algae in the receiving environment.
Fatma Beduk,Senar Aydin,Arzu Ulvi,Mehmet Emin Aydin 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.9
In this study, the occurrences, temporal concentration variations and ecotoxicological risks were determined for 18 polycyclic aromatic hydrocarbons (PAHs); 7 congeners of polychlorinated biphenyls (PCBs), and 18 selected organochlorine pesticides (OCPs) in the anaerobically digested sewage sludge samples obtained from a conventional wastewater treatment plant (WWTP) in Konya, Turkey. Flowrate of the evaluated WWTP was 200,000 m3/day, with the production of 140 tons/day treated sewage sludge. Total 18 PAHs were in the range of 1,203 −17,599 μg/kg of dry matter (dm); total PCBs were in the range of 51.26 – 561.37 μg/kg dm, and total OCPs were in the range of 4.90 – 13.11 μg/kg dm. The highest concentrations were determined for fluoranthene among PAHs, with 2445 μg/kg dm, PCB118 congener with 514 μg/kg dm, and δ-HCH among OCPs with 2.44 μg/kg dm. Considering the average daily production amounts of treated sludge, the highest mass loads were 1,785 g/day for total PAHs; 79 g/day for total PCBs; and 1 − 2 g/day for total OCPs, while the annual mass load was estimated to be approximately 7.3 kg. An ecotoxicological risk assessment was performed by estimation of risk quotients (RQs). High risk for soil ecosystem was identified due to PAHs and PCBs ingredient of sludge, while lower risk was determined for OCPs compounds. The highest RQ values were determined for pyrene (RQ: 1337) among PAHs, PCB118 congener (RQ: 7608), and γ-HCH (RQ: 5.23) among OCPs. Findings of this study show that sewage sludge can be an important source in the spread of persistent pollutants to the environment, and may pose a risk for soil ecosystem.