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21.
This work deals with the mineralogical, geochemical and radiological characterisations of Selmo Formation in Batman neighbourhood. The upper Miocene–Pliocene Selmo Formation is common in the centre of Batman and composed of carbonated sandy claystones and silty–sandy stone lenses. The common whole minerals of the samples are quartz, feldspars, calcite and dolomite. The clay minerals are smectite, illite, chlorite and mixed-layer clay (chlorite–smectite). The geochemical mean values of the samples are 51.7% SiO2; 12.6% Al2O3; 6.2% Fe2O3; 3.6% MgO; 6.3% CaO; 1.1% Na2O; 1.7% K2O; 0.8% TiO2; 0.2% P2O5; 0.1% MnO; and 0.03% Cr2O3. In addition, baseline maps for the concentrations of each radionuclide, the radium equivalent activity and the outdoor gamma dose rate distributions have been plotted for the study area. The mean activity concentrations of 226Ra, 232Th, 40K and 137Cs were determined to be 32, 24, 210 and 9 Bq kg?1, respectively. The assessments of the radiological hazard indices, such as radium equivalent activity, absorbed dose rate in air, annual effective dose equivalent, excess lifetime cancer risk, external hazard index and internal hazard index, were calculated and compared with the internationally accepted reference values. This study shows that the concentrations of radioactivities in the measured samples were within the recommended safety limits and did not pose to be any significant source of radiation hazard.  相似文献   
22.
The tendons of some birds undergo a physiological process of gradual mineralization, usually limited to the central portion of the tendon and resulting in an increase of the elastic modulus and the ultimate strength. The present study was carried out by light microscopy and scanning electron microscopy and was focused on the structural and ultrastructural modifications occurring in this tissue during biomineralization.In comparison with most other tendons, turkey tendons appeared to be more finely subdivided into thinner fascicles and to contain a greater amount of cell-rich endotenon tissue. The most obvious finding, however, was the complete disappearance of the crimps in the calcified portions of the tendon, while they were present with the usual morphology in the non-mineralized portion.The electron microscopy revealed in the mineralized tendon traces of pre-existing crimps, locked in the straightened-out position by the infiltrating mineral phase. This latter was composed of two different types of fine particles, respectively, growing inside and around the collagen fibrils and appearing as tightly packed platelets or as larger, flat platelets regularly arranged in phase with the D-period of collagen. The perifibrillar mineral could play a critical role in the mechanical coupling of adjoining fascicles and in the transmission of tensile loads along the tendon itself.  相似文献   
23.
Color-enhancement investigations without using heating treatment from dull or pale to ideal saturation and/or changes to the formation of the rarer attractive colors are widely conducted to revalue abandoned gem material sources in the world. Such an investigation is carried out on pale or dull purple-colored amethyst and smoky-colored morion samples, which are two important gem species of the crystalline quartz (SiO2) mineral that are currently abandoned in natural deposits in Turkey because of their unattractive coloration. The results of color enhancements observed on these samples, after irradiation with artificial gamma, neutron and beta beams, were examined by comparing with samples with the ideal color saturation and also with colorless samples, using optical absorption (OA) and radioluminescence (RL) spectroscopy. The ICP-AES analyses reveal that the main impurity elements of over 100 ppm in abundance in these quartz species are aluminum, iron and titanium for amethyst, and aluminum, iron, titanium and manganese for morion. The OA spectra indicate that vivid purple coloration of amethyst is due to the transmittance at about 395–420 nm band gap as a result of absorbance peaks at 375, 480 and 530 nm. These absorbances may be related to the unusual oxidized small proportions of certain impurity ions, after being exposed mainly to gamma irradiation, such as Al(IV) from the total aluminum, Ti(V) from the total titanium and Fe(IV) from the total iron, respectively. However, the RL spectroscopy of amethyst samples before and after they were exposed to artificial gamma, neutron and beta radiation beams demonstrates that the ions most affected by irradiation are Fe(IV) first and Al(IV) and Ti(V) second, and these ions represent the RL peaks at 600, 720 and 495 nm, respectively. The OA spectra indicate that dark smoky coloration in morion is due to a lack of transmittance at the visible region as a result of the absorbance peaks at 375, 450–490, 620 and 730 nm. These absorbances also may be related to the unusual oxidized small proportions of certain impurity ions by irradiation, such as Al(IV) from the total aluminum, Ti(V) from the total titanium and Mn(III) from the total manganese, respectively. In addition, the buoyancies of these absorbance peaks in the visible region produce the color hues between light smoky and dark smoky colorations in morion samples. These oxidized ion states are more resistant and stable against environmental destructive conditions in comparison with amethyst. Thus, the dark smoky coloration of morion becomes dull or pale after relatively longer periods. But, the RL spectroscopy of morion before and after being exposed to gamma, neutron and beta irradiation beams demonstrates that the most induced ions from the irradiation are Mn(III) and Al(IV) first and Ti(V) second. These ions represent the RL peaks at about 400, 720 and about 500 nm, respectively.  相似文献   
24.
25.
Native polyacrylamide gel electrophoresis at pH 8.8 did not allow to separate lactate dehydrogenase (LDH) isoenzymes of turkey origin. Five electrophoretically distinguishable forms of the enzyme were detected in serum and tissues of turkey using IEF technique in a pH range of 3–9. Generally, three different groups were seen: (i) those having an anodic domination (heart, kidney, pancreas, and erythrocytes) with mainly LDH‐1 fraction, (ii) those having a cathodic domination (breast muscle and serum) with prevalence of LDH‐5, and (iii) those with a more uniform distribution (liver, spleen, lung, and brain). The specific enzyme activity was the highest in the breast muscle, followed by heart muscle, and brain. Low activities were detected in serum, kidney, and liver.  相似文献   
26.
Sequential extraction procedure (acid extractable, reducible, oxidizable, and residual) proposed by BCR was applied for the determination of trace metals in the River Yesilirmak sediments, Tokat, Turkey. The determination of trace metals in sediment samples was performed by flame atomic absorption spectrometry. The proposed method showed satisfactory recovery, detection limits and standard deviation for trace metals determination in sediment samples. Generally, most of the elements were found in the oxidizable and residual fractions. The total concentrations of trace metals analyzed were found to be (mg/kg) Cu: 37.9, Mn: 392.2, Zn: 126.2, Fe: 3726, and Pb: 29.6, respectively. Results obtained are in agreement with data reported in the literature.  相似文献   
27.
Sideritis niveotomentosa Hub. -Mor. is a local endemic species belonging to the Lamiaceae family. In this study, GC/MS analysis, total antioxidant capacity and anticancer effects of different extracts obtained from S. niveotomentosa were investigated comparatively. Total phenolic contents of extracts were determined by the Folin–Ciocalteu method, total flavonoid contents by aluminum chloride method, and also the free radical scavenging activities of the extracts by DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) assay. The cytotoxic effect of the extracts was studied via MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay on DLD1, HL60 and ARH77 cell lines. Pro-apoptotic gene expression levels were also tested in the most sensitive cell line ARH77 by Real-Time PCR. The expression levels of 4 pro-apoptotic genes, APAF, BAX, CASP3, and HRK were found to be upregulated in ARH77 cells that were treated extracts. Results showed that methanolic extracts contain more phenolic content than acetone extracts, consistent with DPPH results. As a result, Sideritis niveotomentosa extracts, especially methanolic extracts, are rich in phenolic content and have a strong radical scavenging effect. In addition, the extracts showed selective effects on cell lines. This study is pioneering in terms of future studies, and the findings provide hope for future experimentation.  相似文献   
28.
The importance of the effect of phosphate rock depends on the chemical form of phosphorus in which this element is combined. The paper presents the results of inorganic and organic forms of phosphorus in the phosphate rock from Mazidag-Derik, Semikan deposit located at Mardin city at SE Anatolia of Turkey. Total phosphorus concentration in the rock is an average 18.5%. The inorganic phosphorus mean % contents were 99.98% for studied sedimentary phosphate rock. Speciation of inorganic phosphorus was carried out using a method based on sequential extractions of the sedimentary phosphate rock each releasing four forms of inorganic phosphorus: loosely sorbed phosphorus, phosphorus bound to aluminium (P-Al), phosphorus bound to calcium (P-Ca) and phosphorus bound to iron (P-Fe). Calcium bound phosphorus is the dominant form of inorganic phosphorus in the studied sedimentary phosphate rock. Aluminium bound phosphorus is the second, iron bound phosphorus is the third most prevailing form. Loosely bound phosphorus is present in the lowest amounts. Analyses of phosphorus forms in sedimentary phosphate rock using a UV spectrophotometric method and ICP-AES are reported here. For the phosphorus the two methods give the same results and the concentrations are in good agreement with the reference values.  相似文献   
29.
The three-dimensional photoluminescence emissions between 380 and 800 nm of the dentritic agate with white body color from the Dereyalak-?nönü-Eski?ehir (Turkey) region were obtained at the temperatures between 250 and 340 K under 366 nm excitation. The most advantage of three-dimensional photoluminescence graphic in a silica structure is to demonstrate clearly all vibronic structures through temperature increasing on the spectra. Hence, photoluminescence response from the gem-quality material was discussed in relation to chemical impurities of trivalent rare earth elements.

In the photoluminescence spectra, two strong and many weaker emission bands became clear at the lower temperature (250 K) conditions. First strong one is the purple band, and the highest emission peak is observed at 394 nm. Second strong one is the red band, and the highest emission peak is observed at 717 nm. The half-width of these main bands is approximately 17–19 nm, and such band's combination is typical for trivalent rare earth elements. Chemical analyses in this study show the abundances of many rare earth elements in the material. In order of abundance, they are yttrium (845 ppm), gadolinium (238 ppm), lutetium (196 ppm), dysprosium (45 ppm), neodymium (41 ppm), promethium (34 ppm), europium (18 ppm), and scandium (3 ppm). However, the two strong emission bands are, of course, due to yttrium and gadolinium ions, respectively.

As a result, the intensities of these bands gradually decreased forming a sequence until the temperature of 280 K. Hence, the photoluminescence of the Turkish dentritic agates does not exist at higher temperatures, mainly because of high iron (40.000 ppm) abundance.  相似文献   
30.
In this study, the influences of thin film thickness and post-annealing process on the magnetic properties of CoFeB thin films were investigated. The angular dependency and linewidth of the ferromagnetic resonance signal were used to explore the magnetic behavior of sputtered single-layer and trilayer thin film stacks of CoFeB. A micromagnetic simulation model was employed based on the metropolis algorithm comprising the demagnetizing field and in-plane induced uniaxial anisotropy terms with all relevant contributions. Our results reveal that the direction of magnetization changes from in-plane to out-of-plane as a result of the annealing process and induces a perpendicular magnetic anisotropy in the 1-nm thick CoFeB thin film. The ferromagnetic resonance (FMR) linewidth can be defined well by the intrinsic Gilbert damping effect and the magnetic inhomogeneity contribution in both as-grown and annealed samples. The difference between the linewidths of the single and trilayer film is mainly caused by the spin pumping effect on damping which is associated with the interface layers.  相似文献   
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