Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(66)
- Merdan, Mehmet(56)
- Duran, Celal(50)
- Ozdes, Duygu(47)
- Kaygusuz, Abdullah(42)
- Demir, Selim(37)
- Turan, Ibrahim(37)
- Ashyralyyev, Charyyar(34)
- Dokuz, Abdurrahman(33)
- Araz, Onur(31)
- Öztürk, Serkan(31)
- Sipahi, Ferkan(30)
- Kandemir, Raif(28)
- Arslan, Mehmet(27)
- Karsli, Orhan(27)
- Kulakaç, Nurşen(26)
- Baltacı, Cemalettin(25)
- Gücer, Mehmet Ali(25)
- Kurt, Kemal(25)
- Maden, Nafiz(25)
- Ozturk, Samet(25)
- Topal, Fevzi(25)
- Baltaci, Cemalettin(24)
- Yücel, Cem(24)
- Aliyazicioglu, Yuksel(23)
- Bayrakdaroglu, Serdar(23)
- Kankal, Murat(23)
- Peker, Iskender(23)
- Yolcu, Halil(23)
- Reis, Hatice Catal(21)
- Topal, Meryem(21)
- Vural, Alaaddin(21)
- Aydin, Aydanur(20)
- Aydin, Faruk(20)
- Bayraktar, Alemdar(20)
- Kurnaz, Muammer(20)
- Çelik, Necati(20)
- Ürkek, Bayram(20)
- Cakir, Tufan(18)
- Günen, Mehmet Akif(18)
Yayınlar
- MakaleYalnız künye2019Scopus SJRQ2Combined active flow and flight control systems design for morphing unmanned aerial vehicles
Kanat, Öztürk Özdemir; Karatay, Ertuğrul; Köse, Oğuz; Oktay, Tuğrul
In this article, combined active flow control system and flight control system design for morphing unmanned aerial vehicles is applied for the first time for autonomous flight performance maximization. For this purpose, longitudinal and lateral dynamics modeling of morphing unmanned aerial vehicle having active flow control manufactured in Erciyes University, Faculty of Aeronautics and Astronautics, Model Aircraft Laboratory is considered in order to obtain simulation environments. Our produced morphing unmanned aerial vehicle is called as ZANKA-II, which has a mass of 6.5 kg, range of 30 km, endurance of 0.5 h, and ceiling altitude of 6000 m. von Karman turbulence modeling is used in order to model atmospheric turbulence during flight in both longitudinal and lateral simulation environments. A stochastic optimization method called as simultaneous perturbation stochastic approximation is also applied for the first time in order to obtain optimum dimensions of morphing parameters (i.e. extension ratios of wingspan and tail span), optimum positions of blowers, and optimum magnitudes of longitudinal and lateral controllers' gains (i.e. P, I, and D gains) while minimizing cost index capturing terms for both longitudinal and lateral autonomous flight performances and there exist lower and upper constraints on all optimization variables in the literature.
AtıfScopus17WoS14OpenAlex15
İncele - BildiriAçık Erişim2019Numerical solution of Neumann type elliptic overdetermined multipoint mixed boundary value problem
Ashyralyyev, Charyyar; Karabey, Suzan; Cakalli, H.; Kocinac, L.D.R.; Harte, R.; Cavalcanti, V.N.D.; Ashyralyev, A.; Sakalli, I.; Canak, I.; Gurtug, O.
In the present paper, Neumann type elliptic overdetermined multipoint boundary value problem is discussed. The first and second order of accuracy difference schemes (ADSs) for the numerical solution of elliptic overdetermined multipoint boundary value problems are presented. Stability estimates for solutions of difference schemes are obtained. Numerical results for mixed boundary value problem are given.
- MakaleYalnız künye2019Scopus SJRQ2Detecting interaction/complexity within crowd movements using braid entropy
Akpulat, Murat; Ekinci, Murat
The segmentation of moving and non-moving regions in an image within the field of crowd analysis is a crucial process in terms of understanding crowd behavior. In many studies, similar movements were segmented according to the location, adjacency to each other, direction, and average speed. However, these segments may not in turn indicate the same types of behavior in each region. The purpose of this study is to better understand crowd behavior by locally measuring the degree of interaction/complexity within the segment. For this purpose, the flow of motion in the image is primarily represented as a series of trajectories. The image is divided into hexagonal cells and the finite time braid entropy (FTBE) values are calculated according to the different projection angles of each cell. These values depend on the complexity of the spiral structure that the trajectories generated throughout the movement and show the degree of interaction among pedestrians. In this study, behaviors of different complexities determined in segments are pictured as similar movements on the whole. This study has been tested on 49 different video sequences from the UCF and CUHK databases.
AtıfScopus2WoS3OpenAlex5İncele - MakaleAçık Erişim2019Scopus SJRQ2Preliminary investigations on two different procedures to calculate the efficiency and performance ratio of PV modules
Ozden, T.; Akinoglu, B.G.
Short- and long-term outdoor performances of the photovoltaic (PV) modules are extremely important in reaching their economic viabilities. Such information is very valuable for the investors, customers and researchers of PV technologies. Two different procedures are possible, and both are used by many researchers. However, to the best of our knowledge, there is no comparative investigation to evaluate these two procedures. One of the methods uses instantaneous I–V curves of PV modules taken in a specified instant of time, while the others simply use the integrated energy values of the input and the yield of PV modules. In fact, both have advantages and disadvantages. In the present work, we outlined the advantages and disadvantages of both methods and compared them using the data of two different cell-type modules which are installed at GÜNAM’s outdoor test facility. In the analysis, the data that we used are taken under the same outdoor test conditions and ambient weather conditions. The outcomes of these preliminary analyses can be summarized as follows: (1) The procedure that uses instantaneous I–V curves seems dependent on the specified time intervals and ambient weather conditions at that instant; (2) accordingly, we will propose how to determine an optimal time interval to reach better performance results; (3) using the integrated values, we achieved the variations in performances with different integration time periods; (4) preliminary comparisons of these two procedures resulted in key conclusions on performance and degradation calculations of PV modules.
AtıfScopus4WoS2OpenAlex4İncele - Kitap BölümüAçık Erişim2019Ore Mineralogical Study of Cerattepe Au-Cu (±Zn) VMS Deposit (Artvin-Turkey)
Akpınar, I.; Çiftçi, E.; Glagolev, S
The Cerattepe mine, one of the volcanogenic massive sulfide deposits in northeastern Turkey, is hosted within the late Cretaceous volcanic, intrusive and sedimentary rocks. Deposit’s main ore body contains high-grade massive copper sulfides and a gold-silver and barium rich oxide zone, characterized by dense alteration stages, is situated on top of it. Replacement, cataclastic, breccia, dissemination, dendritic, concentric growth, colloform, and framboidal textures were identified. Pyrite, sphalerite, marcasite, chalcopyrite, bornite, galena, tennantite-tetrahedrite, gold, covellite, digenite, chalcocite, cuprite and cubanite constitute the mineral paragenesis where quartz, calcite and barite account for the gangue minerals. Limonite, hematite, lepidocrocite, malachite, azurite and jarosite developed in the oxidation zone.
AtıfScopus3WoS4OpenAlex4İncele - MakaleAçık Erişim2019Scopus SJRQ3Is there prejudice against obese persons among health professionals? A sample of student nurses and registered nurses
Yılmaz, Hacı Ömer; Yabancı Ayhan, Nurcan
Purpose: The aim of this study was to assess whether there is prejudice toward obese persons among student nurses and registered nurses. Design and Method: A total of 379 participants were included (190 student nurses, 189 registered nurses). The Fat Phobia Scale and Belief About Obese Persons Scale were used to determine the prejudice. Findings: Registered nurses were found to have more negative prejudices toward obese persons than those of student nurses. These prejudices were determined to be influenced by the nurses' body mass index and having an obese person in the family. Practical Implications: Both groups had negative prejudices toward obese persons, there was a higher level of prejudice among the registered nurses. These prejudices can have a negative impact on healthcare practices.
AtıfScopus21WoS20OpenAlex26
İncele - MakaleAçık Erişim2019Scopus SJRQ2Effect of pH on protein extraction from sour cherry kernels and functional properties of resulting protein concentrate
Çelik, Mehtap; Güzel, Melih; Yildirim, Metin
The aims of this research were to examine the effect of pH on extraction of proteins from sour cherry (Prunus cerasus L.) kernels, and to investigate the functional properties of the resulting protein concentrate. The optimum pH values for the protein extraction and isoelectric precipitation were determined as 10.0 and 4.5, respectively. The protein concentrate contained 4.03 ± 0.16% moisture, 3.31 ± 0.17% ash, 2.94 ± 0.36% carbohydrate, 1.93 ± 0.16% lipid, and 80.48 ± 2.38% protein. Water holding capacity, oil holding capacity and the least gelling concentration of the protein concentrate were 2.42 ± 0.09 g water/g, 1.73 ± 0.17 g oil/g and 8%, respectively. Results showed that emulsifying activity and stability indices, foaming capacity and stability of protein concentrate were 38.91 ± 2.50 m2/g, 37.49 ± 2.41 min, 35.00 ± 3.54% and 71.80 ± 7.25% (after 30 min), respectively. The functional and chemical properties of the protein concentrate indicate that it may find application as functional ingredient for various food products.
AtıfScopus45WoS41OpenAlex45İncele - MakaleYalnız künye2019Scopus SJRQ2The in situ natural radionuclide (238U,232Th and40K) concentrations in Gümüşhane granitoids: implications for radiological hazard levels of Gümüşhane city, northeast Turkey
Maden, Nafiz; Akaryalı, Enver; Çelik, Necati
We have carried out 48 in situ measurements on radioactivities of 238U, 232Th and 40K isotopes at the Gümüşhane granitoid plutons employing gamma-ray spectrometer with a NaI(Tl) scintillation detector. The radionuclide activity concentrations of 40K, 238U and 232Th ranged from 62.6 to 1680.8 Bq kg−1, 2.5 to 119.9 Bq kg−1 and 3.3 to 92.4 Bq kg−1, respectively. The mean concentration of natural radionuclides (40K, 238U and 232Th) was found to be 638.5 ± 421.6 Bq kg−1, 40.8 ± 27.4 Bq kg−1 and 33.5 ± 25.5 Bq kg−1, respectively. The mean values of the radium equivalent and the external hazard index were 137.9 ± 80.6 Bq kg−1 and 0.37 ± 0.22, respectively. The value of annual effective dose equivalent value (81.8 μSv year−1) is lower on average than in the world average of 460 μSv year−1. The external hazard index acquired in this study did not exceed the international safety standard levels, which means that Gümüşhane pluton does not produce any radiation hazards to the dwellers.
AtıfScopus9WoS8OpenAlex8İncele - MakaleYalnız künye2019Scopus SJRQ1Water soluble chitosan-caffeic acid conjugates as a dual functional polymeric surfactant
İlyasoğlu, Huri; Guo, Zheng
A water soluble chitosan-caffeic acid conjugate (C-CAC) was prepared by chemical modification of chitosan using activated caffeoyl with dimethyl aminopyridine as a catalyst. The C-CAC was characterized using UV–visible spectrometry, Fourier transform infrared, nuclear magnetic resonance spectroscopies and differential scanning calorimetry. The caffeoyl content in the C-CAC was 65 mg/g. To study the introduction of a new function into chitosan, the antioxidant activities of the synthesized C-CAC was determined using three in vitro assays: DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), and ferric reducing antioxidant power. The half inhibition concentration values for DPPH and ABTS radicals were 370 and 172 μg/ml, respectively; showing its good radical scavenging activity. The emulsifying properties of the C-CAC were investigated by preparing 10% fish oil-in-water emulsions. C-CAC not only showed a good ability to stabilize oil-in-water emulsions, but also was more effective in retarding lipid oxidation compared to chitosan; implying that the synthesized C-CAC was functioning in an oil-in-water emulsion system as both emulsifier and antioxidant. Chitosan-phenolic conjugates, as a biopolymer-based surfactant, may represent a promising ingredient for enabling stable oxidation-sensitive oil-in-water emulsions.
AtıfScopus45WoS43OpenAlex44İncele - MakaleAçık Erişim2019Scopus SJRQ2Effects of pavement surface deformations on traffic flow
Aydin, Metin Mutlu; Topal, Ali
Pavement surface deformations have a significant effect on speed profile of vehicles and traffic flow conditions. These deformations limit driving properties and increase vehicle operation and maintenance costs. Additionally, they cause many problems such as accidents, slower movement speeds, capacity loss and severe discomfort states. There are many factors having an effect on road capacities and they vary according to different road and traffic flow conditions. In this study, it is aimed to investigate and develop models to estimate shockwave and bottleneck forming, capacity loss and speed reduction, which occurred on examined road links caused by pavement deformations. For the prediction of road capacity, flow–density (q–k) relationship, bottleneck and shockwave analysis methods were used. In the scope this study, deformed road links were divided into three sections; Section A – before deformation zone, Section B – deformation zone, and Section C – after deformation zone. All three sections were investigated and empirical results were obtained. According to analysis results, it was found that pavement surface deformations have a negative effect on the level of road service capa-bility. Obtained results also showed that there are significant reductions in capacity relatively by up to 44 and 26% would result from surface deformations on deformed lanes and non-deformed adjacent lanes.
AtıfScopus12WoS10OpenAlex14İncele - MakaleAçık Erişim2019Scopus SJRQ3Complementary and alternative treatment methods for menopausal hot flashes used in Turkey
Ozcan, Handan; Çolak, Pınar; Oturgan, Berna; Gülsever, Esra
Objective: Study was planned to determine complementary and alternative treatment methods for menopausal hot flashes. Methods: Women who reported their discomfort of hot flashes as a degree of discomfort of 4 or more according to the Visual Analogue Scale (VAS) were included in the study (n:356). In data collection, Questionnaire Form and Complementary and Alternative Medicine Approaches Scale were used. Results: The average age of the women was 56.65±6.05 and the average age of menopause was 46.39±5.25. According to VAS, the average severity of hot flashes was 7.85±1.83. Women with obesity and any chronic disease were more likely to have hot flashes. It was determined that 73.6% of women in the menopausal period were using Complementary and Alternative Medicine (CAM). It was determined that women were using herbal supplements, dietary supplements, mind-body practices and religious practices against the discomfort of hot flashes. 72% of women using CAM stated that the method used was effective. Conclusions: Women who use CAM usually use it with information that is out of the knowledge of health profession and lack of information. It is recommended to carry out extensive studies for CAM methods and the mechanisms of action that women use.
AtıfScopus13WoS12İncele - MakaleYalnız künye2019Scopus SJRQ1Ohmic heating assisted hydrodistillation of clove essential oil
Tunç, Merve Tuğçe; Koca, İlkay
Ohmic heating assisted hydrodistillation is a novel green technology for the extraction of essential oils. In this study, clove bud essential oils (CEO) were extracted by ohmic heating assisted hydrodistillation (OAHD) and compared with conventional hydrodistillation (HD) process, in terms of extraction yield, energy consumption and chemical properties. Ohmic heating assisted hydrodistillation process conditions were optimized by response surface methodology. Voltage gradient (7.5–12.5 V/cm, A), process time (30–120 minutes, B) and mass of clove bud (20–40 g, C) were varied in order to maximize CEO yield and to minimize energy consumption. Optimized extraction conditions were determined as, 12.5 V/cm voltage gradient, 97.967 min for process time and 40 g of mass of clove bud. Yield of CEO and energy consumption were found 13.18 ± 1.50% and 0.214 ± 0.030 kW h/g CEO at optimum extraction conditions, respectively. Under optimum conditions, both OAHD and HD methods were used for CEO extraction. Yields of CEO obtained by OAHD, HD-D (distilled water) and HD-S (salted water) were 13.18 ± 1.50, 8.23 ± 0.35 and 7.88 ± 0.60 respectively. Energy consumptions of OAHD and HD methods were not significantly different (P > 0.05). The main chemical component of CEO was eugenol and the yield of eugenol (g/100 g clove bud) was found higher with OAHD (6.95±0.6) method than HD-D (5.16 ± 0.20) and HD-S (5.13 ± 0.28). Antioxidant and antimicrobial properties of CEOs were investigated by FRAP, DPPH and disk diffusion method. Antioxidant properties of CEOs obtained by different extraction methods were not significantly different (P > 0.05) according to FRAP and DPPH analysis. Although inhibition zones of CEOs extracted with different methods were not significantly different (P > 0.05) for gram positive bacteria's, CEO obtained by OAHD and HD-D have significantly higher (P < 0.05) inhibition zones for K. pneumonia and E. coli, respectively. The results of this study showed that OAHD method is applicable for CEO production.
AtıfScopus87WoS66OpenAlex90İncele - MakaleYalnız künye2019Scopus SJRQ3Inhibition profiles of Voriconazole against acetylcholinesterase, α-glycosidase, and human carbonic anhydrase I and II isoenzymes
Topal, Fevzi
In this work, the inhibitory activity of Voriconazole was measured against some metabolic enzymes, including human carbonic anhydrase (hCA) I and II isoenzymes, acetylcholinesterase (AChE), and α-glycosidase; the results were compared with standard compounds including acetazolamide, tacrine, and acarbose. Half maximal inhibition concentration (IC50) values were obtained from the enzyme activity (%)-[Voriconazole] graphs, whereas Ki values were calculated from the Lineweaver-Burk graphs. According to the results, the IC50 value of Voriconazole was 40.77 nM for α-glycosidase, while the mean inhibition constant (Ki) value was 17.47 ± 1.51 nM for α-glycosidase. The results make an important contribution to drug design and have pharmacological applications. In addition, the Voriconazole compound demonstrated excellent inhibitory effects against AChE and hCA isoforms I and II. Voriconazole had Ki values of 29.13 ± 3.57 nM against hCA I, 15.92 ± 1.90 nM against hCA II, and 10.50 ± 2.46 nM against AChE.
AtıfScopus32WoS30OpenAlex30İncele - MakaleYalnız künye2019Scopus SJRQ1Mapping of shallow landslides with object-based image analysis from unmanned aerial vehicle data
Comert, Resul; Avdan, Ugur; Gorum, Tolga; Nefeslioglu, Hakan A.
The Black Sea Region of Turkey is one of the most landslide prone areas due to its high slope topography, heavy rainfall, and highly weathered hillslope material conditions. Preparation of landslide inventory maps is the first step in producing landslide susceptibility maps. Ground-based methods for mapping landslide occurrences are time-consuming and expensive. Additionally, landslide mapping based on satellite imageries and aerial photographs has some limitations, including climatic conditions, cost, and limited repetitive measurement capacity. Visual interpretation-based landslide mapping, which is based on satellite imageries and aerial photographs, is a time-consuming procedure that requires an experience-based expert opinion. Therefore, the data acquisition based on unmanned aerial vehicle (UAV) and landslide event inventory maps using an object-based classification approach can be superior to other methods in terms of speed and cost. In this study, we developed a semiautomatic model using object-based image analyses for rapid mapping of shallow landslides from the data obtained from UAVs after major landslide events in the Black Sea Region of Turkey. For this purpose, two test sites—Kurucasile (Bartin) and Cayeli (Rize)—were selected. Landslide mapping models were developed in the investigation sites, and the performance of the models was evaluated. The landslides' data obtained with the developed models were compared to the landslides' data produced by the experts. The comparison process revealed that landslides mapped by using UAV data have an accuracy rate higher than 86% according to the number of landslides and 83% according to the landslide area.
AtıfScopus76WoS55OpenAlex70İncele - MakaleYalnız künye2019Scopus SJRQ1Theoretical investigation on combustion characteristics of ethanol-fueled dual-plug SI engine
Altın, İsmail; Bilgin, Atilla; Sezer, İsmet
In this study, effects of equivalence ratio, spark timing and spark plug number and locations on combustion characteristics were theoretically investigated using an ethanol-fueled dual-plug SI engine. Two-zone quasi-dimensional model was used throughout analyses. Three spark plug configurations (diagonally, centrally and side located), three equivalence ratios (0.8, 0.9, and 1.0), and three spark timings (−30, −25, and −20 CA @ BTDC) were considered to analyze variation of total burn duration, mass fraction burned, cylinder pressure, and temperatures (exhaust and maximum burned gas). Variation of mass fraction burned and cylinder pressure were also investigated at lean mixture ratio and 2800 rpm (MBT engine speed). Lastly, the effect of engine speed on total burn duration, maximum cylinder pressure and aforementioned temperatures were investigated in the range of 1000–6000 rpm. The findings show that dual-plug configuration yields approximate combustion characteristics by comparison with centrally located single plug configuration in ethanol-fueled SI engine.
AtıfScopus30WoS27OpenAlex28İncele - MakaleAçık Erişim2019Scopus SJRQ2Determination of the wear performance of diamond saw blades using inductively coupled plasma
Inal, Serkan; Erkan, Ilker; Aydiner, Kerim
Saw blades are one of the most used cutting tools. They compose the expensive parts of a cutting machine. Therefore, saw-blade wear is an important parameter governing the economy of the cutting process. Significant savings could be made when it is controlled effectively. In this study, a new methodology is employed for the determination of the saw-blade wear in the cutting of two types of marble. Wear of segments is determined by high-precision inductively coupled plasma method. Two types of marbles were used to investigate the wear performance of diamond-impregnated segments of circular saw-blade matrix. Taguchi mixed design L16 (43 21) is used as an experimental design and the results are evaluated statistically with Minitab. The results reveal that the specific wear rate (SWR) of Beige marble increases with the increase of the peripheral speed, traverse speed, depth of cut and down-cut mode operation. Additionally, it is demonstrated that the traverse speed and peripheral speed are the dominant cutting parameters affecting the SWR. It is also seen that similar trends are observed for Onyx marble (excluding peripheral speed). Finally, it is concluded that the proposed models can be effectively used for the estimation of the SWR.
AtıfScopus4WoS2OpenAlex6İncele - BildiriYalnız künye2019Module Level Global Maximum Power Point Tracking Strategy
Basoglu, Mustafa Engin
Partial shading of photovoltaic (PV) modules can occur at any time due to the obstacles such as chimney, tree, antenna, bird flock etc. Due to such obstacles, the entire surface of the PV module cannot receive an equal amount of irradiance; Therefore, PV modules cannot operate at its maximum power point (MPP). In this paper, an improved version of a 0.8VOC model based global maximum power point tracking (GMPPT) strategy has been proposed. Single ended primary inductance converter (SEPIC) is used as a power converter between PV module and load. Effectiveness of the proposed technique is presented by experimental studies with the comparison of a full scanning approach. Results of experimental studies show that proposed GMPPT strategy outperforms than full scanning based algorithm known.
AtıfScopus3WoS2OpenAlex2İncele - MakaleYalnız künye2019Scopus SJRQ1Performance evaluation of ejector with different secondary flow directions and geometric properties for solid oxide fuel cell applications
Genc, Omer; Timurkutluk, Bora; Toros, Serkan
The mixing chamber length, secondary flow tube inclination angle, diffuser length and diverging angle as well as the direction of secondary flow on the ejector performance are numerically studied. The numerical results of 2560 different design points including the all combinations of the selected parameters indicate that the selected ejector geometric parameters have a great impact on the ejector performance. Within the parameter ranges considered, the best performance based on steam to carbon ratio and the entrainment is obtained from the ejector having a mixing chamber length of 30 mm, secondary flow tube inclination angle of 45°, diffuser length of 90 mm and diffuser diverging angle of 5°, regardless of the secondary flow direction. On the other hand, the parallel flow ejector, where the anode exhaust line flow direction is designed to be parallel to the primary flow direction, is found to exhibit slightly higher steam to carbon ratio and entrainment ratio compared to those of the counter flow ejector. Furthermore, it is seen that the parallel flow ejector can offer wider ranges of the ejector geometric parameters considered for a high performance whereas relatively rigid geometric parameters need to be selected for designing a counter flow ejector.
AtıfScopus17WoS15OpenAlex16İncele - MakaleAçık Erişim2019Scopus SJRQ2Volatile constituents and biological properties of essential oils from aerial parts of Gentiana gelida BIEB
Üçüncü, Osman; Karataş, Şeyda Merve; Baltacı, Cemalettin; Karaköse, Mustafa; Türkuçar, Semra Alkan
This work reports the chemical composition, antimicrobial and antioxidant activities of essential oils from the aerial parts of Gentiana gelida BIEB. for the first time in literature. The oils from the aerial parts (flower, leaf and stem) were obtained by Clevenger-type apparatus and characterized by GC-FID and GC-MS. While tricosane (21.67%) was the main component of flower oil, hexadecanoic acid was the most abundant component of leaf and stem oils in ratios 26.46% and 31.89%, respectively. Additionally, all essential oils of G. gelida were investigated for their antimicrobial activity against eight Gram negative bacteria, four Gram positive bacteria and five fungi, using agar dilution method and antioxidant activities by using 2,2-diphenyl-1-picrylhydrazyl radical scavenging and Folin-Ciocalteu assays. The flower oil of G. gelida showed stronger antimicrobial and antioxidant activities than those of stem and leaf. The amount of total phenolic content and scavenging activity of the flower oil were found 525.35±8.24 mg GAE/L and 49.30±1.25%, respectively.
AtıfScopus5WoS4OpenAlex4İncele - MakaleYalnız künye2019Scopus SJRQ1Enhancing of the nonlinear absorption and optical limiting performances of the phthalocyanine thin films by adding of the single walled carbon nanotubes in poly(methyl methacrylate) host
Yuksek, Mustafa; Kaya, Elif Çelenk; Karabulutlu, Nur; Kaya, Ahmet Afşin; Karabulut, Mevlut; Elmali, Ayhan
Unlike the earlier nonlinear optical studies of single walled carbon nanotubes (SWCNTs) which were generally carried out as solvent, in this study, we established to deposit the unsoluble SWCNTs as homogeneous thin films by blending them with phthalocyanines in PMMA host. The structural and morphological features of the thin films were studied by SEM and TEM imaging techniques while the linear, nonlinear-absorptions and carrier dynamic properties of the thin films were investigated with the UV–Vis spectrophotometer, open aperture Z-scan experiments and pump-probe technique, respectively. In addition, the optical limiting performances of the samples were calculated from nonlinear absorption spectra. It was observed that the linear- and nonlinear-absorptions and optical limiting performance of the thin films increased with the mixing of the SWCNT sample with the Pcs complexes. We have clearly explained the mechanisms contributing to the nonlinear optical absorption and optical limiting performances.
AtıfScopus12WoS11OpenAlex10İncele