Room-temperature ferromagnetism in transparent transition metal-doped titanium dioxide     

Matsumoto Y  Murakami M  Shono T  Hasegawa T  Fukumura T  Kawasaki M  Ahmet P  Chikyow T  Koshihara S  Koinuma H 《Science (New York, N.Y.)》2001,291(5505):854-856

Dilute magnetic semiconductors and wide gap oxide semiconductors are appealing materials for magnetooptical devices. From a combinatorial screening approach looking at the solid solubility of transition metals in titanium dioxides and of their magnetic properties, we report on the observation of transparent ferromagnetism in cobalt-doped anatase thin films with theconcentration of cobalt between 0 and 8%. Magnetic microscopy images reveal a magnetic domain structure in the films, indicating the existence of ferromagnetic long-range ordering. The materials remain ferromagnetic above room temperature with a magnetic moment of 0.32 Bohr magnetons per cobalt atom. The film is conductive and exhibits a positive magnetoresistance of 60% at 2 kelvin.  相似文献   

Body weight of young broilers fed with declining calcium and phosphorus contents during the starter period is irresponsive to changes in the skeleton     

Canan Kop-Bozbay  Ahmet Akdag  Helin Atan  Nuh Ocak 《Journal of animal physiology and animal nutrition》2021,105(4):747-756

To evaluate the effect of reduced calcium (Ca) and available P (aP) levels in starter diets on growth performance and tibia, sternum and serum characteristics, and to assay the association between Ca and P (aP) intakes and these variables, 600 one-day-old broiler chicks (Ross 308) were used in a 21-days trial. Broilers were randomly allotted to five treatments with five replicate pens. Chicks were fed on one of the five starter diets that were formulated with a 10% reduction in the Ca and aP contents, starting from the control diet and hence, named as C (0.96% Ca, 0.45% aP), L1 (0.85% Ca and 0.42% aP), L2 (0.77% Ca and 0.38% aP), L3 (0.68% Ca and 0.34% aP) and L4 (0.61% Ca and 0.31% aP). Declining dietary Ca and aP levels did not affect body weight and levels of Ca, P and alkaline phosphatase in serum, but reduced linearly feed intake, the feed conversion ratio and the bone weight and ash content. The Ca and aP intakes and Ca:aP ratio displayed a positive correlation with both tibia and sternum weights, and the mass of the bones were equally sensitive to dietary Ca and aP levels. In conclusion, the body weight of young broilers was irresponsive to changes in the skeleton when exposed to early dietary Ca and aP restrictions (up to 0.61% Ca and 0.31% aP) and the mechanostat had limits due to the association between Ca and aP intakes, and bone properties.  相似文献   

Using caesium-137 measurements to investigate soil erosion rates in western Istanbul (NW Turkey)   总被引：3，自引：0，他引：3  

Sevilay Haciyakupoglu  T. Ahmet Ertek  Des E. Walling  Z. Fatih Ozturk  Gursel Karahan  A. Evren Erginal  Nilgun Celebi   《CATENA》2005,64(2-3):222

Buyukcekmece Reservoir, located in the western outskirts of Istanbul, is one of the major water resources of Istanbul, and supplies drinking water to about 4 million people. Erosion in the catchment of the reservoir is an important problem in terms of its longer-term sustainability for water supply. There is an urgent need to obtain reliable quantitative data regarding erosion and deposition rates within the catchment to assess the magnitude of the problem and to plan catchment management strategies. In the absence of existing data, attention has focussed on the potential for using ¹³⁷Cs measurements to provide retrospective estimates of medium-term soil erosion rates within the catchment over the past ca. 40 years. To date, the ¹³⁷Cs approach has not been used to document soil redistribution rates in Turkey and this contribution reports an attempt to confirm the viability of the approach and the results of a preliminary investigation of rates of soil loss from uncultivated areas within the catchment. The soil redistribution rates estimated using the profile distribution conversion model varied from − 16.11 (erosion) to 4.59 (deposition) t/ha/year.  相似文献   

Removal of Remazol Red Rb by using Al (III) as Coagulant-Flocculant: Effect of Some Variables on Settling Velocity     

Gürses  Ahmet  Yalçin  Mehmet  Dogar  Cetin 《Water, air, and soil pollution》2003,146(1-4):297-318

This study addresses the research of the removal of a textile dye from aqueous solutions by using aluminum ions as coagulant-flocculant. A simulated textile wastewater was prepared from Remazol Red RB textile dye. The purpose of this study was to investigate the effects of temperature, pH, and concentrations of the cationic surfactant and electrolyte concentration on the settling velocity ofthe simulated textile wastewater. While investigating these factors, levels of variables were determined by considering the characteristicsof traditional textile wastewater like pH, temperature, and dye concentration. Although traditional coagulation-flocculation processesmake use of different aluminium salts as coagulant-flocculent, in this study, Al ions dissolved in pH and temperature of traditional textilewastewater were used. Furthermore, sludge volume index values (SVI) were determined and conductivity measurements carried out. The resultsshowed that, in the working range of these variables, the spectroscopic color measurement revealed 100% decolorization yieldof wastewater. In conclusion, researchers found that the optimum settling velocity conditions were as follows: low temperature (273K),surfactant concentration of 0.10 g L^-1, electrolyte concentration of 0.10 g L^-1, dye concentration of 0.025 g L^-1 and a pH of 10.05. Finally, by conducting experiments twice under the obtained optimum values, mean settling velocity was 0.014 m min^-1 and the mean sludge volume index 140 mL g^-1.  相似文献   

Clinicopathologic diagnosis of cutaneous toxoplasmosis in an Angora cat     

Kul O  Atmaca HT  Deniz A  Süer C 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(9-10):386-389

This report deals with a case of cutaneous toxoplasmosis in a 2 year-old female Angora cat. Cutaneous lesions were characterized by prescapular ulcers and hyperemic nodules in the skin of the inguinal and dorsosacral regions. A skin biopsy sample was collected from the lesioned area and processed for histopathologic examination and immunoperoxidase test using Toxoplasma gondii and Neospora caninum specific antibodies. Toxoplasma gondii immunopositive reactions were detected in keratinocytes and dermal macrophages while no immunoreactivity was detected for N. caninum. The case of cutaneous toxoplasmosis was further confirmed by PCR analysis using T. gondii B1 gene-specific primers. In conclusion, we report the first case of cutaneous toxoplasmosis in Angora cats.  相似文献   

Radon Survey and Exposure Assessment in Karaca and ?al Caves, Turkey     

Ugur Cevik  Ayhan Kara  Necati Celik  Mustafa Karabidak  Ahmet Celik 《Water, air, and soil pollution》2011,214(1-4):461-469

Radon concentration and gamma activity concentration of naturally occurring radionuclides were determined and presented for two tourist caves (Karaca and Çal caves) in this study. These caves are reported to receive about 77,000 visitors during the summer season in 2007. It was seen that mean radon activity concentrations for the winter and summer seasons for the Karaca cave is 1,023 and 823 Bq/m³ and for the Çal cave is 264 and 473 Bq/m³. Mean ²²⁶Ra, ²³²Th, and ⁴⁰K activity concentrations are found to be 43, 19, and 262 Bq/kg for the Karaca cave and 31, 27, and 460 Bq/kg for the Çal cave. Doses received by the cave guides due to radon were estimated to be 2.9 mSv/year for the winter season and 2.3 mSv/year for the summer season for the Karaca cave. Same values were estimated for the Çal cave, and the results were found to be 0.6 mSv/year for the winter season and 1.1 mSv/year for the summer season. Annual effective doses received by the visitors in both caves were estimated to be in the order of ??Sv/year because of the short exposure time comparing the cave guides. Although the reported values are below the recommended values, both groups are exposed to possible radiological risk during their stay inside the cave, since prolonged exposure to high radon concentration has been linked to lung cancer.  相似文献   

Effects of Exogenous Glycinebetaine and Trehalose on Cadmium Accumulation and Biological Responses of an Aquatic Plant (Lemna gibba L.)     

Fatih Duman  Ahmet Aksoy  Zeki Aydin  Ridvan Temizgul 《Water, air, and soil pollution》2011,217(1-4):545-556

This study aimed to investigate and compare the effects of exogenous glycinebetaine (GB) and trehalose (TR) on the biological responses of duckweed (Lemna gibba L.) against cadmium (Cd) accumulation. Duckweed samples were exposed to 0.5, 1, and 3 mM of Cd for 6 days in the presence and absence of GB (0.5, 1, 2, and 5 mM) or TR (0.5, 1, 2, and 5 mM). The accumulation of Cd, GB, and TR were investigated, and their influence on the rates of lipid peroxidation, photosynthetic activity, proline content and enzymatic antioxidant performance was examined. Two-way ANOVA showed that exposure to Cd and/or GB or TR caused an increase in Cd accumulation concentration dependently. TR had significant effects on Cd accumulation. The application of 0.5 mM TR increased Cd accumulation, whereas 5 mM decreased Cd accumulation. However, Cd accumulation was not significantly affected by the presence of GB. Cd concentration alone or in combination with GB or TR had a significant effect on lipid peroxidation, photosynthetic activity, proline content, and antioxidant enzyme activities. In addition, statistically significant GB?CCd and TR?CCd interactions were observed. We conclude that both GB and TR play protective roles against Cd stress in aquatic plants. The use of a low level of TR (i.e., 0.5 mM) may be more useful than GB in phytoremediation studies.  相似文献   

Chemical compositions and insecticidal effects of essential oils isolated from Achillea gypsicola, Satureja hortensis, Origanum acutidens and Hypericum scabrum against broadbean weevil (Bruchus dentipes)     

Elif Tozlu  Ahmet Cakir  Saban Kordali  Goksel Tozlu  Hakan Ozer  Tulay Aytas Akcin 《Scientia Horticulturae》2011

The essential oils of aerial parts of Achillea gypsicola Hub.-Mor., Hypericum scabrum L., Satureja hortensis L., and Origanum acutidens (Hand.-Mazz.) Letswaart were analyzed in this study by GC and GC–MS and their oils were tested for toxicity against broadbean weevil (Bruchus dentipes). A. gypsicola oil contained camphor (40.17%), 1,8-cineole (22.01%), piperitone (11.29%), borneol (9.50%) and α-terpineol (1.56%) as major components. A total of 74 components were identified by GC–MS in H. scabrum oil, including α-pinene (9.26%), terpinen-4-ol (5.12%), camphor (5.94%), δ-cadinene (4.52%), pulegone (4.45%), γ-muurolene (4.12%), pinocarvone (3.97%) and β-caryophyllene (3.42%) as predominant components. The essential oils of O. acutidens and S. hortensis were characterized by high contents of carvacrol (86.99% and 55.74%), γ-terpinene (0.71% and 20.94%), p-cymene (1.95% and 12.30%), α-terpinene (0.13% and 2.04%) and β-caryophyllene (1.30% and 1.08%). All of the essential oils were toxic to adults of B. dentipes and insect mortality increased with increasing concentration of each oil. The oils (20 μl dose) brought about 100% mortality in 36 h. Although desirable insecticidal activities against the pest were achieved with the oils from all four plant species, S. hortensis and O. acutidens oils were more effective, particularly after 6 h of treatment. The current results concluded that the essential oils, in particular O. acutidens and S. hortensis oils, may be used as potential botanical insecticides against B. dentipes.  相似文献   

Characteristics of some almond kernel and oils     

Mehmet Musa Özcan  Ahmet Ünver  Esin Erkan  Derya Arslan 《Scientia Horticulturae》2011

The proximate properties, the fatty acid and mineral contents of different almond kernel varieties were determined. The crude protein contents of kernels ranged between 12.7% (guara) and 16.3% (cristomorto). The oil yields from these kernels were established between 48.8% (cristomorto) and 55.7% (ferragnes). The acidity value of oils were found between 1.389 and 3.559%. In addition, peroxide values were established between 7.586 (nonpareil) and 15.590 mequiv./kg (cristomorto). The major fatty acids of almond kernel oils were oleic (72.5–79.9%), linoleic (13.5–19.8%) and palmitic acids (5.9–6.7%). The predominant mineral in most kernel was potassium (13.1–15.1 mg/100 g). The mineral contents of the kernels were established as 7.94–9.38 mg/100 g potassium, 2.9–4.0 mg/100 g magnesium and 1.84–2.94 mg/100 g calcium. From the results of the present study, it can be concluded that the kernels of almond varieties are being potential sources of valuable oil which might be used for edible and other industrial applications.  相似文献   

Preparation and application of an<Emphasis Type="Italic">s</Emphasis>-triazine-based novel<Emphasis Type="Italic">N</Emphasis>-halamine biocide for antimicrobial fibers     

Jaewoong Lee  Royall M. Broughton  Akin Akdag  S. D. Worley  Tung S. Huang 《Fibers and Polymers》2007,8(2):148-154

N-halamines serve as important antimicrobial agents. Development of this class of compounds has been shown to provide benefits especially from a biocidal point of view. A novels-triazine-basedN-heterocycle, dichloro-m-aminophenyl-hydantoinyl-s-triazine (DAPHT), which could be rendered antimicrobial through exposure to diluted chlorine bleach, was synthesized and characterized by¹H NMR,¹³C NMR, and FT-IR. A finishing method was used to apply theN-halamine precursor onto cotton fabric, and the optimum conditions for finishing were investigated. The DAPHT-treated cotton fabric had durable antimicrobial properties up to 50 standard washing cycles and was rechargeable under normal laundry/bleaching conditions. The antimicrobial efficacy against Gram-positive and Gram-negative bacteria was demonstrated.  相似文献