المؤلفون: A. Tumuklu, E. Daanoba Sunkari, F. Yalcin, O. Ozer Atakoglu

المصدر: International Journal of Environmental Science and Technology. 20:5391-5404

مصطلحات موضوعية: Environmental Engineering, Environmental Chemistry, General Agricultural and Biological Sciences

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::471fba5090ef2017fa817dba25750502Test
https://doi.org/10.1007/s13762-022-04519-8Test

المؤلفون: O. Ozer Atakoglu, Fusun Yalcin, Daniel G. Nyamsari, Mustafa Gurhan Yalcin

المصدر: International Journal of Environmental Science and Technology. 19:1335-1356

مصطلحات موضوعية: Calcite, Environmental Engineering, Dolomite, Geochemistry, Cordierite, Weathering, 010501 environmental sciences, engineering.material, 01 natural sciences, chemistry.chemical_compound, Augite, chemistry, engineering, Environmental Chemistry, Carbonate, General Agricultural and Biological Sciences, Ankerite, Geology, 0105 earth and related environmental sciences, Magnetite

الوصف: This study investigates chemical properties, the statistical variation in elements, paleo-environmental properties and accumulation, density maps, degree of weathering and the classification of the beach sand. Forty-seven samples were collected along the sampled beach sand. Chemical analysis was done on fine grains of all 47 beach sand samples and coarse grains of 19 selected rock samples by X-ray fluorescence analysis. CaO, SiO2 and MgO were the most abundant major elements in the samples. CaO and MgO show high concentrations in the northern section of the study area, while SiO2 is more prevalent in the southern section of the study area. Relatively higher concentrations of CaO, Al2O3, Fe2O3, TiO2, K2O, P2O5 and SO3 were observed in the fine grains, due to their susceptibility to weathering, while relatively higher SiO2 and MgO were observed in the coarse grains due to their resistance to weathering. Calcite and dolomite are major sources for the high concentrations of Ca and Mg, especially in the northern sections of the study area, while augite, clinoenstatite, ankerite, clinopyroxene, cordierite, magnetite are likely sources of Si, Mg and Fe. The beach sand indicated a mixture of high-CaO source type and high-SiO2 source type, with the high-CaO type dominating. Investigations revealed the sand as marine carbonaceous to carbonaceous ferrites with magnesium association, deposited in an oxic environment where the marine skeleton could not be preserved due to high aerobic activity, and not far from their carbonate (neritic) parent source. The high-SiO2 resulted from the Tekirova ophiolite in the region.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::17bbdec042b8636c4014ac18042d3fb3Test
https://doi.org/10.1007/s13762-021-03280-8Test

المؤلفون: Ousmane, L. M. (Laminou), Salamatou, A. I. (Abdourahamane), Iro, D. G. (Dan), Abdoul-Aziz, B. M. (Beido), Ali, M. (Mahamane), Pierre, O. (Ozer)

المصدر: International Journal of Environment, Agriculture and Biotechnology

الوصف: Waste management continues to be a critical environmental issue in cities. It impacts on the well being of the population, the environment and the biodiversity. In the city of Maradi, in Niger, more interest is given to the problem in order to understand the whole waste management system. It is in this context that this study is carried out to investigate on the role of ruderal flora on the municipal solid wastes dumpsites and landfill sites in Maradi city. The specific objectives are to determine the floristic diversity and distribution of ruderal flora on the municipal solid waste disposal sites, and to identify potential species that can play an important role in the phytoremediation of these sites. In total, 65 species belonging to 52 genera and 24 families were recorded. These species can be categorised into two groups containing anthropic and nitrophilic species according to the ascending Hierarchical Classification (AHC) at 25% similarity. Characteristic species of the first group G1 are Amaranthus viridis and Cucurbita pepo, and Datura innoxia and Cucumis melo for the second group G2. Other ruderal species, namely Amaranthus spinosus L., Amaranthus viridis L., Celosia trygina L., Datura innoxia Mill., and an introduced woody species, Cuphea hyssopifolia Kunth., found are not included in the Maradi city list of species. Datura innoxia, Amaranthus viridis and Amaranthus spinosus are species known to tolerate different degrees of pollution and their ecology should be further study to better understand how they can be used for phytoremediation on this kind of sites.

وصف الملف: application/pdf

العلاقة: https://www.neliti.com/publications/238722/species-diversity-and-distribution-of-ruderal-flora-on-landfills-in-maradi-cityTest

الإتاحة: https://www.neliti.com/publications/238722/species-diversity-and-distribution-of-ruderal-flora-on-landfills-in-maradi-cityTest

المؤلفون: Sevim, O. (Ozer), Filazi, A. (Ahmet), Toprak, B. (Baran), Kartal, S. (Saruhan)

المصدر: International Journal of Advanced Engineering Research and Science

الوصف: Alkali activated mortars obtained from granulated blast furnace slag and fly ash were used instead of Portland cement by activating with alkali. Sodium silicate and sodium hydroxide were activated blast furnace slag and fly ash. Mortar samples were prepared 40x40x160 mm as prismatic samples according to TS EN 196-1 and they were cured at room temperature. Compressive and flexural strength of the mortar samples including blast furnace slag and fly ash were investigated by experimenting.

وصف الملف: application/pdf

العلاقة: https://www.neliti.com/publications/237045/investigating-of-mechanical-properties-of-mortars-based-on-fly-ash-and-blast-furTest

الإتاحة: https://www.neliti.com/publications/237045/investigating-of-mechanical-properties-of-mortars-based-on-fly-ash-and-blast-furTest

المؤلفون: J.L. HEE, N. BOJDO, M. QUINN, A. FILIPPONE, O. OZER

مصطلحات موضوعية: AEROSPACE, FLOW CONTROL

الوصف: An inertial particle separator is a device fitted to the intakes of air-breathing engines to remove foreign object debris, dust particles, and water droplets. Their primary aim is to clean the inbound air in order to protect the rotating turbo-machinery from premature damage. They are commonly found on helicopters and short take-off military turboprop aircraft, and work by forcing particle-laden air around a bend before bifurcating the flow into clean (core) and dirty (scavenge) channels [1]. An EU Horizon 2020 innovative project called A New Technology Innovation for Foreign Object Debris removal (ANTIFOD) has been established to develop a prototype of an intake protection system for the turbo-compressor of a more-electric aircraft air management system. In such an architecture, the air used for cabin pressurisation is taken directly from the atmosphere external to the aircraft, mitigating the need to bleed air off the turbofan engine compressor stage; hence improving the overall efficiency and reducing fuel burn. However, removing the turbofan and several stages of compressor from the pathway of fresh air to the cabin, leaves the replacement compression system vulnerable to erosion, corrosion, and structural damage by ingested particulates, water and foreign object debris, severely shortening its working life. The major challenge of this project is to develop a protection system that extends the turbo-compressor maintenance intervals to reasonable levels within a strict pressure loss budget, and across a wide range of atmospheric conditions. The design requirements are quite unique in comparison to prior art, thereby necessitating a fresh approach to particle separator design. To enable the necessary investigations, we have developed a new facility for testing particle separators of this scale and application. The paper discusses the design of an experimental rig whose test section is a scaled two-dimensional planar particle separator geometry which was designed to permit full optical access for flow visualisation and two-phase particle image velocimetry studies. The 1:2 scale rig, shown in Figure 1, has been sized to replicate duct Reynolds numbers of the full-scale geometry at the key operating points. The test section housing is designed to accommodate other multi-channel IPS configurations, and facilitate investigations of span-wise flow on particle separation through the use of an aluminium-perspex layered configuration. We discuss the reasoning for geometric scaling, sizing of centrifugal pumps and filters, flow control and metering as well as data acquisition systems. Within this contribution we present the capabilities of the facility, demonstrated using a well-characterised geometry from the literature [2] (inset, Figure 1). Rig characteristic data, shown in Figure 2, shows the range of inlet Reynolds numbers and scavenge mass flow proportions that the rig is capable of achieving. The dataset was created by systematically adjusting a set of sleeves to alter the amount of air bled into the perforated pipe. This causes a change in the suction in each leg of the separator, thereby modifying the share of inlet mass flow into the core and scavenge channels (known as the split flow parameter, ?), and the inlet Reynolds number as characterised by hydraulic diameter. In Figure 2a we show the range of attainable ? values, which narrows with increasing flow rate, as ? tends towards the area ratio of the scavenge and core outlet areas (1:4) at the suction source. At a corrected mass flow rate of 0.17 kg/s, the split flow parameter rapidly increases. This indicates a breakdown of the flow within the separator, caused by an adverse pressure gradient around the surface of the separation hump, leading to a greater proportion of flow entering the scavenge leg, rather than the core. This is demonstrated in Figure 2b, which shows a large rise in core pressure loss at an inlet Reynolds number of around 110,000, followed by a plateauing of the core pressure drop and a greater sensitivity to ?. We conclude the paper with some examples of the flow diagnostic techniques available for validating numerical simulations, including Particle Image Velocimetry (PIV). We demonstrate the benefit of the layered configuration in capturing 3-dimensional flow features, but also discuss practical drawbacks we encountered. Finally, we shown preliminary results of a particle shadow-based imaging system capable of capturing particle velocity, size and shape at primary bounce locations, which may be used to obtain restitution coefficient data for implementation in numerical simulations.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::d2f4c62f38d2bff22bb3bf328e4a1b87Test

المؤلفون: O. Ozer, H. Koklu

المصدر: Kerntechnik. 85:380-386

مصطلحات موضوعية: Physics, Nuclear and High Energy Physics, Neutron transport, Radiation, Condensed matter physics, Scattering, Isotropy, Extension (predicate logic), Anisotropic scattering, Quadratic equation, Nuclear Energy and Engineering, General Materials Science, Safety, Risk, Reliability and Quality, Anisotropy, Critical thickness

الوصف: The effect for different types of scattering on the critical half thickness in slab geometry for one speed neutron transport equation is studied for isotropic, linearly anisotropic and quadratic anisotropic scatterings. An extensive numerical survey is carried out for the critical thickness in order to provide the effect of the different scattering types. The numerical results are obtained by PN, TN and UN methods. The PN method is the Legendre polynomial solution that is accepted as the exact result for the neutron transport theory calculations and the UN and TN methods are the types of Chebyshev polynomials. Critical thickness values are calculated by using Mark boundary condition. Results are compared with the literature

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::2a591c7abc38777e616c4d7397bec182Test
https://doi.org/10.3139/124.190042Test

المؤلفون: Z. C. Sahin, O. Ozer

المصدر: Mathematics in Natural Science. :29-38

مصطلحات موضوعية: Combinatorics, Diophantine equation, Tuple, Mathematics

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::98de9b40b5bff2fb19cb26ffe66d7b10Test
https://doi.org/10.22436/mns.03.01.04Test

المؤلفون: D. Bellaouar, O. Ozer

المصدر: BULLETIN OF THE KARAGANDA UNIVERSITY-MATHEMATICS. 93:48-58

مصطلحات موضوعية: integer sequences, Discrete mathematics, real quadratic fields, Integer sequence, integer basic element, Type (model theory), continued fraction, Yokoi's invariants, Quadratic equation, General Earth and Planetary Sciences, fundamental unit, General Environmental Science, Mathematics, Fundamental unit (number theory)

الوصف: In this paper, we determine the real quadratic fields Q(root d) coincide with positive square-free integers d including the continued fraction expanison form of w(d) - [a(0);7,7,...7,a(l)/l-1]. Furthermore, we deal with determining fundamental units and Yokoi's d-invariants n(d) and and in the relation to continued fraction expansion of w(d) where (d) is a period length of w(d) for the such type of real quadratic number fields Q (root d). The present paper improve the theory of fundamental unit which generates the unit group of real quadratic fields and also determine the special form of continued fraction expansion of integral basis element in real quadratic fields.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f51346af058a29ec00cf653ead2cd00fTest
https://doi.org/10.31489/2019m1/48-58Test

المؤلفون: Cem Çöteli, Necla Ozer, H T Ozer, O Ozer, Mehmet Levent Sahiner, Ahmet Kıvrak

المصدر: European Heart Journal. 40

مصطلحات موضوعية: medicine.medical_specialty, Ejection fraction, Longitudinal strain, business.industry, Strain (injury), medicine.disease, Brain natriuretic peptide, Dipyridamole, Internal medicine, medicine, Cardiology, Ghrelin, Left ventricular diastolic dysfunction, Cardiology and Cardiovascular Medicine, business, Heart failure with preserved ejection fraction, medicine.drug

الوصف: Background Diastolic dysfunction is an important factor in the development of heart failure with preserved ejection fraction (HFpEF). As the ejection fraction is preserved in HFpEF, the diagnosis of this disease with non-invasive methods is difficult. Purpose In this study, the relationship of BNP, NT-proBNP, Ghrelin, and echocardiographic 3D strain findings with diastolic dysfunction was investigated in patients undergoing left heart catheterization. Methods Our study is a cross-sectional study and included 78 patients in whom echocardiography was performed, and who underwent left heart catheterization based on relevant indications. The patient data recorded for evaluation included the findings from left heart catheterization, follow-up 3D echocardiography; and the levels of blood NT-proBNP, and Ghrelin. Results The rate of diastolic dysfunction was 42.3%. Longitudinal 2D and 3D mean strain as absolute values were observed to decrease more in patients with diastolic dysfunction. The median levels of BNP, NT-proBNP, and Ghrelin levels were higher in patients with diastolic dysfunction. The independent predictors of diastolic dysfunction were determined to be the left atrial volume index (LAVI) (OR=1.17; p=0.018), longitudinal 3D strain values (OR=1.88; p Relationship Between LV EDP and LV Longitudinal Strain LV EDP 2D Strain 3D Strain r p r p r p BNP, pg/ml 0.429 Measurement of longitudinal strain Conclusion In conclusion, our study found out that the reduced 3D strain absolute values and increased levels of NT-proBNP and Ghrelin biomarkers predicted diastolic dysfunction. If further large-scale studies prove the efficiency of these practical, they may not only allow for making a diagnosis of HFpEF more readily but may also eliminate the confusion in diagnostic algorithms. Acknowledgement/Funding None

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::a19588bb54407f6de2c857010b19d741Test
https://doi.org/10.1093/eurheartj/ehz748.0254Test

المؤلفون: Koc, A., Kutbay, Y. B., Ozyilmaz, B., Kirbiyik, O., Erdogan, K. M., Kaya, O. Ozer, Guvenc, M. Saka, Ozdemir, T. R.

العلاقة: ede2d9ce-7ab1-44dc-aacf-454eec7aebb6; https://avesis.deu.edu.tr/publication/details/ede2d9ce-7ab1-44dc-aacf-454eec7aebb6/oaiTest

الإتاحة: https://avesis.deu.edu.tr/publication/details/ede2d9ce-7ab1-44dc-aacf-454eec7aebb6/oaiTest