Some structural properties of CdO:F films produced by ultrasonic spray pyrolysis method

The fluorine doped cadmium oxide (CdO:F) samples have been deposited at 250 °C by ultrasonic spray pyrolysis method. Cadmiumacetat-dihydrat and ammonium fluoride have been taken as a source of cadmium and fluorine-dopant respectively. The thickness of the CdO:F samples was about 1.4 μm. X-ray diffraction pattern of the CdO:F samples has revealed that the samples are polycrystalline with cubic sodium chloride structure. There are shifts of the d values (interplanar spacing) for CdO:F samples with respect to standard CdO film. The lattice parameters for cubic structure have been calculated using the Bragg equation. The texture coefficients calculated for various planes at different fluorine concentrations indicate that the samples have exhibited (111) and (200) preferential orientations.     

Effects of fluorine doping on the structural properties of the CdO films deposited by ultrasonic spray pyrolysis

The fluorine doped cadmium oxide samples have been deposited at 250 °C by ultrasonic spray pyrolysis method. X-ray diffraction patterns of the CdO:F samples have revealed that the samples are polycrystalline with cubic sodium chloride structure. The texture coefficients calculated for various planes at different fluorine concentrations indicate that the samples have exhibited (1 1 1) and (2 0 0) preferential orientations. The lattice parameters for cubic structure of each diffraction plane have been calculated. The crystallite size of the samples being nearly constant until 4% of fluorine doping showed reasonable decrease above this concentration value. The macro strain and dislocation density vary with fluorine concentrations.     

Hard iron boride (Fe2B) on 99.97 wt% pure iron

Some properties such as hardness and fracture toughness of boride formed on the 99.97 wt% pure iron were investigated. Boronizing was carried out in a solid medium, consisting of Ekabor powders of 5% B₄C as donor, 5% KBF₄ as an activator and 90% SiC as diluent at 800 °C for 2, 4 and 8 h. The dominant phase formed on the substrate was found to be Fe₂B that had a finger-like shape morphology. The hardness of boride on the 99.97% pure iron was over 1700HVN, while the hardness of pure iron was about 130HVN. It was found that the fracture toughness of boride formed on surfaces of 99.97% pure iron, depending on the process time, ranged from 3.59 to 3.83 MPa m^1/2. Depending on process time and temperature, the depth of the boride layer ranges from 22 to 43 μm, leading to a diffusion-controlled process.     

Appraisal of self, social environment, and state authority as a possible mediator of posttraumatic stress disorder in tortured political activists.

This study examined appraisal of self and others, as measured by semantic differential ratings of Police, State, Society, Family, Friend, Myself as a Man/Woman, and Myself as a Political Person, in 55 tortured political activists in Turkey, 55 nontortured political activists, and 55 nontortured, politically noninvolved controls. There were no remarkable differences between tortured and nontortured political activists; both groups differed from controls in having a more negative appraisal of the police and the state and stronger perceptions of danger, mistrust, and injustice in relation to state authority. Lack of beliefs concerning a "benevolent state" may have protected the survivors from the traumatic effects of state-perpetrated torture. Further research into the possible protective role of belief systems in posttraumatic stress disorder is needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Trade-offs in the OTA-based analog filter design

Operational transconductance amplifiers (OTAs) are widely used in the design of electronically tunable circuits. However, electronic tunability ranges of the OTA based filters are restricted by the limited bandwidth of the transconductance gain of the OTA. Furthermore, stability conditions and the linearity of the OTA which depends on the control current restrict the tunability. In this paper, some trade-offs in the electronically tunable filters are investigated. In addition, the tunability ranges of some first and second order OTA-C and OTA-RC filters are comparatively examined. Moreover, an OTA-C all-pass filter circuit is presented. SPICE simulations are performed and stability analyses are given for both of the OTA-C and OTA-RC filters. Operation of the presented all-pass filter is verified experimentally.     

The single nerve fiber action potential and the filter bank--a modeling approach

Single fiber action potentials (SFAPs) from peripheral nerves, such as recorded with cuff electrodes, can be modelled as the convolution of a source current and a weight function that describes the recording electrodes and the surrounding medium. It is shown that for cuff electrodes, the weight function is linearly scaled with the action potential (AP) velocity and that it is, therefore, possible to implement a model of the recorded SFAPs based on a wavelet multiresolution technique (filterbank), where the wavelet scale is proportional to the AP velocity. The model resulted in single fiber action potentials matching the results from other models with a goodness of fit exceeding 0.99. This formulation of the SFAP may serve as a basis for model-based wavelet analysis and for advanced cuff design.     

Determination of cadmium and selected micronutrients in commonly used and traded medicinal plants in Turkey

BACKGROUND: Medicinal plants commonly used and traded in Turkey were monitored for their cadmium and selected micronutrient (copper, iron, manganese and zinc) content. RESULTS: Cadmium was not detected in any sample of licorice extract, linden flowers or nettle leaves. However, in the rest of the samples, cadmium was found in the range of 7–126 µg kg^?1, with the highest concentration in chamomile leaf. Of all the monitored trace elements, the highest concentration found was 520 mg kg^?1 iron in zahter. The highest copper, manganese and zinc concentrations were found in rose hips (24 mg kg^?1), Turkish oregano (58 mg kg^?1) and zahter (50 mg kg^?1), respectively. CONCLUSION: The results of the present study reveal that cadmium and trace element concentrations in medicinal plants commonly used as traditional medicines in Turkey are well below the critical levels. Copyright © 2007 Society of Chemical Industry     

In vitro antioxidant/free radical scavenging and antibacterial properties of endemic oregano and thyme extracts from Greece

The present investigation was to evaluate the antioxidant and antibacterial activities of hexane and methanol extracts from Origanum vulgare ssp. hirtum and Thymus vulgaris (Komotini, Greece). The methanol extracts of oregano and thyme against DPPH radical were more active than the hexane extracts (mean values 0.94 and 0.47, respectively) and oregano exhibited stronger activity than thyme (mean values 0.82 and 0.55, respectively). The results from the β-carotene/linoleic acid assay showed that all plant extracts inhibited linoleic acid oxidation up to 70.78±1.17%. The oregano extracts exhibited the strongest inhibition against Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus using the disc diffusion assay. The chemical composition of the hexane and methanol extracts, by using GC-MS, showed that carvacrol, thymol, and p-cymene were the most prominent compounds. The methanol extract of oregano was found the most potent antioxidant with the highest content of total phenolics (138.92 mg GA/g extract) and carvacrol (76.7%).