Koleksiyon/r/bayburt/10001

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Koleksiyondaki öğeler

  • MakaleYalnız künye2021Scopus SJRQ1
    An investigation of the fatigue performance of adhesively bonded step-lap joints: An experimental and numerical analysis

    Gavgali, Esma; Sahin, Resul; Akpinar, Salih

    Adhesively bonded joints are used in many engineering applications and are manufactured by joining various materials together. Static and dynamic analysis of adhesively bonded joints is very important in both scientific and sector studies on these joints. In this study, the static and fatigue strengths of single-lap joints (SLJs) and three-step-lap joints (TSLJs) that were subjected to tensile and four-point bending tests were examined experimentally and numerically. Adhesively bonded joints were produced using DP460 toughened type adhesive and AA2024-T3 aluminum alloy was used as the adherent. Fatigue tests were performed at a loading ratio (R) of 0.1 and a frequency of 10 Hz. As a result, applying a step-lap to the overlap area of adhesively bonded joints considerably increased the tensile static and fatigue strength of the joint. For the single-lap joint, both the static tensile and the tensile fatigue lifetime limit value of the three-step-lap joint increased approximately 100%. One of the reasons for that increase was that the moment effect formed in single lap joints due to the eccentric loading is minimized and the other is that a step-lap applied to the overlap area retards the formation of damage. However, static bending and fatigue strength values of TSLJs significantly decreased compared to those of SLJs. In addition, the results of the experimental and numerical analyses were found to be highly compatible with each other.

    AtıfScopus29WoS28OpenAlex35
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  • MakaleAçık Erişim2020
    Characterization of pistachio processing industry wastewater and investigation of chemical pretreatment

    Tırınk, Sevtap; Nuhoğlu, Alper; Kul, Sinan

    This study was carried out in two stages; in the first stage of the study, wastewater characterization of wastewater originating from the pistachio industry was primarily completed, and in the second stage, chemical pre-treatment studies were completed. Pistachio wastewater used in the study was obtained from a pistachio processing factory located in Gaziantep province. In chemical treatment studies, montmorillonite clay, AlCl3, Al2(SO4)3, Fe2(SO4)3 and FeCl3 were used as coagulants. As a result of chemical treatability tests, AlCl3 was determined to be the best coagulant. With AlCl3 at optimum dosage and optimum pH value, 99.6% suspended solid (SS) removal efficiency, 65.8% chemical oxygen demand (COD) removal efficiency and 85.5% total phenol (TP) removal efficiency were obtained.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus7OpenAlex9TR Dizin2
    ScopusTR Dizinİncele
  • MakaleAçık Erişim2022Scopus SJRQ4
    Mathematical language of students with learning disabilities in the context of length

    Güven, Dilsad; Argün, Ziya

    Mathematics is language dependent. Part of learning mathematics is learning the mathematical language. Learning disabilities are defined as disorders that are related to listening, thinking, speaking, writing, and reading that are seen in the processes of understanding or using a verbal or written language. In this context, the present study aimed to reveal the understanding and usage of the mathematical language of students with learning disabilities in the context of the concept of length. This study was conducted as a case study. The participants of the study were 4th grade and 5th grade students with learning disabilities. Data collection was conducted through semi-structured clinical interviews during a teaching experiment based on the concept of length and analysed using the content analysis method. According to the findings, the students with learning disabilities had a different and limited understanding, as well as usage of various mathematical terms including length, height, perimeter, half and centimetre.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus3OpenAlex3
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  • MakaleAçık Erişim2022Scopus SJRQ2
    Characterization of Essential Oil and Wastewater from Thymus nummularius M. Bieb. and Micromorphological Examination of Glandular Trichomes

    Gerçek, Yusuf Can; Bayram, Sinan; Çelik, Saffet; Canlı, Deniz; Mavaldi, Muhammed Halid; Boztas, Kadir; Bastürk, Fatma Nur; Kırkıncı, Seran; Yesil, Yeter; Kösesakal, Taylan

    This study aimed to determine the volatile profile by GC-MS and antimicrobial activity of the essential oil isolated from Thymus nummularius using the microwave-assisted hydrodistillation method and morphologically characterize the glandular trichomes in leaf samples. Obtained essential oil, as well as wastewater obtained during essential oil isolation, were chemically (polyphenolic compounds, organic acids, total phenolic content, total flavonoid content and antioxidant activity) characterized. As a result of GC-MS analysis of the essential oil, different ratios of essential oil components were identified, predominantly thymol (38.91%), linalool (13.12%) and geraniol (6.51%). The antimicrobial activity results showed that T. nummularius essential oil has a broad-spectrum inhibitory effect against all target microorganisms (bacteria and yeast-like fungi). Screening of 32 polyphenolic compounds and 52 organic acids in the wastewater was performed by LC-MS/MS and the major polyphenolic compound and organic acid were determined as caffeic acid (97316.85 µg/kg) and malic acid (6898.88 mg/kg), respectively. While the total phenolic and flavonoid content of the wastewater were 35.91 mg GA/g and 34.91 mg QE/g, respectively, the antioxidant activity results were obtained using the CUPRAC, CERAC and ABTS tests were 86.28 mg TE/g, 72.85 mg TE/g and 47.88 mg TE/g. These results support that the T. nummularius, an important production area in Turkey, can be used in different industrial areas due to its rich bioactive content. In addition, it can be said that wastewater is also considered a valuable source of bioactive substances.

    AtıfScopus11WoS8OpenAlex11
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  • MakaleAçık Erişim2020
    RP-HPLC-UV Analysis of the Phenolic Compounds, Antimicrobial Activity Against Multi-Drug Resistant Bacteria and Antioxidant Activity of Fruit and Seed of Diospyros lotus L.

    Akar, Zeynep; Karakurt, Aylin; Okumus, Funda; Cinemre, Sedanur; Duzgun, Azer Ozad; Akar, Bulent; Can, Zehra

    The object of the present study was to investigate the antioxidant, antimicrobial activity and phenolic compounds of fruit and seeds of Diospyros lotus L. The fruits consumed by humans as nutrients were harvested from the plants that grow naturally in the province of Trabzon-Akçaabat, Eastern Black Sea Region of Turkey. The antioxidant activities of fruit and seeds of Diospyros lotus were determined by using four methods (% DPPH radical scavenging activity, FRAP antioxidant power determination, CUPRAC reducing antioxidant activity and total phenolic content (TPC) in five different proportion of methanol-water extracts. All extracts of fruit and seeds of D. lotus analyzed through whole antioxidant analysis methods showed significant antioxidant activity. In addition, antimicrobial activity of fruit and seeds extracted with DMSO was determined against seven standard bacteria and three multi-drug resistance clinical strains. Although fruit extracts did not have the antimicrobial activity against bacteria, seeds showed antimicrobial effect to both standard strains (Gram-negative and Gram-positive) and antibiotic resistance clinical isolates (Klebsiella pneumoniae carrying blaKPC, Acinetobacter baumannii, harboring blaOXA-23 gene and resistance to colistin, and multi-drug resistant Pseudomonas aeruginosa). MICs’ value of plant seed extracts for standard strains was 0.75-25 mg/mL and antibiotic resistant clinical bacteria were 12.5 and 25 mg/mL. Additionally, phenolic compounds in methanol extracts of fruit and seeds were also determined in by HPLC using 19 standards. Gallic acid and chrysin phenolic compounds were the major phenolic compounds in fruit and seeds, respectively.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus8OpenAlex9TR Dizin3
    ScopusTR Dizinİncele
  • BildiriYalnız künye2022
    Evaluating Path Selection Strategies with Blockchain-based Routing in Multi-Domain SDNs

    Guler, Evrim; Karakus, Murat; Uludag, Suleyman

    Software-Defined Networking (SDN) has emerged as one of the most prolific inventions in the general area of computer communications over the past decade. Among many of the touted benefits, SDN architecture facilitated by OpenFlow has the potential to help network administrators to provide End-to-End (E2E) Quality of Service (QoS)-guaranteed paths for flows among networks while providing finer-granular flow management along with global network view. In our previous work, we have introduced QoSChain to amalgamate the advantages of blockchain and SDN for inter-network QoS provisioning to orchestrate an agile and software-driven traffic management framework in order to facilitate cross-network policy automation, assurance, E2E visibility, control and validation. In this study, we focus on the impact of the path selection strategies on the performance of the overall QoSChain performance. Specifically, we exploit three simple but effective path selection strategies, First Feasible Path Selection (FFPS), Random Feasible Path Selection (RFPS), and Minimum Hop Path Selection (MHPS), to evaluate their performance, impact, and overhead in terms of the flow setup time, message overhead, and network resource consumption metrics. Our preliminary simulations results show that the path selection plays an important role in the overall performance with hop count minimization delivering a superior performance offset by an initial higher setup times.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus7OpenAlex9
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  • MakaleYalnız künye2020Scopus SJRQ2
    Study on the radiation attenuation properties of locally available bees-wax as a tissue equivalent bolus material in radiotherapy

    Islam, Sazirul; Mahmoud, K.A.; Sayyed, M.I.; Alim, Bünyamin; Rahman, Md.M.; Mollah, A.S.

    In radiation therapy field, bolus material is frequently utilized when treating different areas of a patient, like at the ears or nose, and to provide build-up of dose to the skin surface. The bolus material must be cost effective, suitably flexible to conform to the surface of the patient, and most importantly should be tissue equivalent. The main objective of this work was to estimate the photon attenuation properties of locally available bees-wax and to assess the feasibility of using this bees-wax as a bolus material practice for treatment of cancer patient. The mass attenuation coefficient (μ/ρ) values have been calculated by using MCNP5 simulation code over the wide range of photon energy (0.015–10 MeV). Some related parameters such as the effective atomic number and the mean free path were also calculated to understand the photon attenuation ability of the investigated bolus material. The attenuation properties were also computed for water, tissue and commercial bolus materials for comparison. Evaluation of the results showed that the radiation attenuation properties of locally available bees-wax have a good similarity to water/tissue. Referring to the results of this study, it is proposed that locally available bees-wax is a suitable substance to be used as bolus material practice for treat of cancer patient.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus59WoS53OpenAlex63
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  • MakaleAçık Erişim2021Scopus SJRQ4
    The effect of pH on removal of phosphate from water using aluminum electrodes by electrocoagulation method; [Alüminyum elektrotlar kullanılarak elektrokoagülasyon yöntemi ile sulardan fosfat gideriminde pH'ın etkisi]

    İrdemez, Şahset; Bingül, Züleyha; Kul, Sinan; Ekmekyapar Torun, Fatma; Demircioğlu, Nuhi

    In this study, the effect of wastewater pH on phosphate removal by electrocoagulation method using aluminum plate electrodes was investigated. For this purpose, experiments were carried out at initial pH values ranging from 3-10, and the effect of the initial pH of the wastewater on phosphate removal efficiency, energy consumption and reaction rate was analyzed. From the results obtained, it was determined that the initial pHs of the optimum wastewater was 3 and 4. Because at low pH, both phosphate removal efficiency is high and the energy consumption of the system is low. While 97% removal efficiency is reached in 20 minutes at pHi=3, it increases in this period with the increase of the wastewater initial pH. These data show that the removal rate is higher at lower initial pHs. While the 1st degree reaction rate constant at pHi=3 is k1=0.2154 min-1, this value decreases to k1=0.071 min-1 at pHi=10. At pHi=3, the energy consumption of the system has been determined as 0.553 kWh m-3 in 12 minutes of contact time. In addition, in the measurements made during the trials, it was observed that the highest PO4-P removal occurred during the period when the pH of the system was between 5-7.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus4OpenAlex1
    ScopusTR Dizinİncele
  • MakaleAçık Erişim2021Scopus SJRQ3
    The influence of metallostatic pressure, grain refiner, and modification on the critical solid fraction (CSF) of cast A380 alloy

    Çolak, Murat; Dispinar, Derya

    In this work, porosity formation with regard to the change in the metallostatic pressure was investigated. Different geometry was generated to simulate the effect of pressure on critical solid fraction. A380 alloy was sand cast. Additionally, the effect of grain refiner and modifiers was also investigated. Samples were subjected to X-ray radiography and density measurement to quantify the pore size and distribution.

    AtıfScopus3WoS3OpenAlex3
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  • MakaleYalnız künye2021Scopus SJRQ1
    An embedded mixed method study on teaching algebraic expressions using metacognition-based training

    Öztürk, Mesut

    That the students are aware of the learning process and know how they learn is important in terms of both controlling their previous learning and building their new learning on the previous ones. This thinking process, which generally requires metacognitive skills, may facilitate the difficulties experienced by the students while passing on from arithmetic to algebraic thinking. This study had two purposes:(1) to examine the effect of the IMPROVE method, a metacognitive training method, on the academic achievement of middle school students regarding algebraic expressions and (2) to examine the teaching process of algebraic expressions with IMPROVE. This study was conducted as an embedded mixed design. Forty-nine sixth grade students participated in the quantitative part of the study, while only six students from the experimental group participated in the qualitative part. The quantitative results of the study showed that there was a significant difference between the students’ total achievement scores regarding algebraic expressions and the achievement scores in the questions requiring high-level thinking skills in favor of the experimental group. It has been found in the comparisons made based on cognitive field levels that there is a statistically significant difference in favor of the group that received metacognition-based education in synthesis level questions. The qualitative results indicated that this teaching method increased students’ interest, contributed to their conceptual learning and improved their various affective characteristics. Also, it has been determined that the students who receive metacognition-based education do enjoy learning with this teaching method and that they think this method should be sustainable for the upcoming lessons.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus15WoS10OpenAlex22
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2022Scopus SJRQ1
    Molecular Cloning, Expression and Characterisation of a Bacterial Myrosinase from Citrobacter Wye1

    Cebeci, Fatma; Mayer, Melinda J.; Rossiter, John T.; Mithen, Richard; Narbad, Arjan

    Glucosinolates are plant natural products which on degradation by myrosinases give rise to the beneficial bioactive isothiocyanates. Recently, a myrosinase activity was detected in a Citrobacter strain isolated from soil. This enzyme was purified enabling its amino acid sequence and gene sequence (cmyr) to be determined. In order to study this myrosinase it was necessary to establish an expression system that would enable future work such as a structural determination of the protein to be carried out. The myrosinase gene was amplified, cloned and expressed in Escherichia coli with a 6XHis-tag. The heterologous expression of cmyr enabled relatively large amounts of myrosinase to be produced (3.4 mg cmyr/100 ml culture). Myrosinase activity was determined by mixing substrate and enzyme and determining glucose release. Optimum pH and temperature were determined to be pH 6.0 and 25 °C for the Ni-NTA purified protein. The kinetic parameters of the purified myrosinase were determined using sinigrin as a substrate. Km and Vmax were estimated as 0.18 mM and 0.033 mmol/min/mg respectively for sinigrin under optimum conditions and compared to other kinetic data for myrosinases. The substrate specificity of myrosinase was determined having the highest affinity for sinigrin followed by glucoiberin, progoitrin, glucoerucin, glucoraphanin and glucotropaeolin.

    AtıfScopus21WoS14OpenAlex16
    ScopusWeb of SciencePubMedİncele
  • Kitap BölümüYalnız künye2022
    Regulation of Natural Food Additives

    Öztekin, Sebahat; Anaya, Katya; Yurdunuseven-Yildiz, Aysun

    The use of natural ingredients in food formulation has been facing an increasing demand worldwide. Aiming to preserve the consumer’s health and provide better guidance to the food industry, regulatory agencies must propose precise definitions and establish safe limits of use for additives of natural origin. In this book chapter, we discuss the lack of specific regulations for natural additives and list the substances currently approved by two important regulatory agencies in the globe: the European Food Safety Authority (EFSA) and the Food and Drug Administration (FDA) from the United States. Other regulatory documents from Asia, Australia, and South America are briefly mentioned. Clearly, there is a need for an international regulatory consensus to minimize ambiguity around the term ʼnatural’ with a better understanding of what the term “natural” meant and how it can be applied to food labelling and international trade.

    • SDG 2 · Açlığa Son
    AtıfScopus15OpenAlex9
    Scopusİncele
  • MakaleAçık Erişim2022Scopus SJRQ2
    On the plane receding contact between two functionally graded layers using computational, finite element and artificial neural network methods

    Öner, Erdal; Şengül Şabano, Bahar; Uzun Yaylacı, Ecren; Adıyaman, Gökhan; Yaylacı, Murat; Birinci, Ahmet

    The frictionless double receding contact problem for two functionally graded (FG) layers pressed by a uniformly distributed load is addressed in this paper. The gradation in the layers is assumed to follow an exponential variation through the height with constant Poisson's ratios. The lower layer rests on a homogeneous half-plane (HP). There is no adhesion between the FG layers or between the lower layer and the HP. The body forces of the FG layers and HP are ignored. First, the governing equations are reduced to a system of two singular integral equations with contact pressures and contact lengths as unknowns using Fourier transform techniques and boundary conditions. The integral equations are solved numerically using the Gauss-Chebyshev integration formula. Then, a parametric finite element analysis is performed using the augmented contact method. Finally, the problem was extended based on the multilayer perceptron (MLP), an artificial neural network used for different problem parameters. The effects of stiffness parameters, the normalized load length, the ratio of shear moduli, the ratio of FG layer heights to the normalized contact lengths, and normalized maximum contact pressures are explored. The results of finite element analysis and the MLP approach are used to validate the normalized maximum contact pressures and contact lengths obtained from an analytical method based on elasticity theory, and finally, good agreement between these three methods results is obtained. The obtained results could help in designing multibody indentation systems with FGMs.

    AtıfScopus85WoS84OpenAlex48
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  • MakaleAçık Erişim2021Scopus SJRQ3
    A study on free-radical scavenging activity, individual phenolic compounds and element concentration of propolis; [Propolisin serbest radikal temizleme aktivitesi, bireysel fenolik bilesik içerigi ve element konsantrasyonu üzerine bir çalisma]

    Ecem Bayram, Nesrin

    The aim of this study was to assess the quality of five propolis samples obtained from Turkey (TP), China (CP), Brazil (BP1, BP2), and Ethiopia (EP). The phenolic compounds of the propolis were identified and quantified using the liquid chromatography-tandem mass spectrometry technique (LCMS/ MS). In addition, quality parameters such as total flavonoid content, total phenolic content, freeradical scavenging activity and element contents were investigated. As a result of LC-MS/MS analysis, the extracts were sorted as TP> BP1> BP2> CP> EP in terms of the total concentration of individual phenolic compounds. Chlorogenic acid was determined as the dominant compound in BP1 and EP, pcoumaric acid as the dominant compound in the BP2 and trans-ferulic acid as the dominant compound in the samples from CP and TP. The concentration of DPPH was higher in TP whereas the ABTS concentration was almost similar to other propolis extracts. The contents of potassium (K), calcium (Ca), iron (Fe), magnesium (Mg) and sodium (Na) in the propolis samples were in the range of 2416.75- 14416.02 mg/kg, 8.52-613.25 mg/kg, 102.66-1425.82 mg/kg, 523.84-7336.74 mg/kg and 57.65-191.15 mg/kg, respectively. Consequently, it is again supported that chemical characteristics and activity of propolis varies according to its geographical origin with this study.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus1OpenAlex3
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  • MakaleAçık Erişim2021Scopus SJRQ1
    3D-graphene-laser patterned p-type silicon Schottky diode

    Orhan, Elif Oz; Efil, Esra; Bayram, Ozkan; Kaymak, Nuriye; Berberoğlu, Halil; Candemir, Ozun; Pavlov, Ihor; Ocak, Sema Bilge

    The influence of the laser patterning (LP) process on the quality of graphene (Gr) film and Schottky diode characteristics was researched in this study. First of all, p-type silicon (Si) was patterned by homemade femtosecond laser source. To compare the resulting effect, non-patterned n-Si and p-Si were used as substrates. To achieve vertically oriented three-dimensional (3D) Gr nanosheets (VGNs) onto the laser patterned p-type Si, non-patterned n-Si, and p-Si substrates, we used Radio-Frequency Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) technique. Then, Raman analyses for VGNs obtained on patterned and non-patterned p-Si and n-Si substrates were conducted. All results indicate that the Gr obtained on all substrates is vertically oriented. Scanning electron microscopy (SEM) analyses were also performed to obtain information about the morphological properties of the 3D Gr structure. In addition, the influence of the laser patterning at the Gr-Si interface was evaluated by comparing two sets of devices which are junctions of Gr-Laser Patterned Si (Gr-LPSi) and Gr-Insulator-Silicon (Gr-I-Si) at 300 K in the dark medium. D1 device consists of a Gr-LPSi junction that involves RF-PECVD grown Gr on the silicon, whose surface exposed the laser beam for patterning. D2 device consists of a Gr-I-Si junction that involves RF-PECVD grown Gr onto the silicon, whose surface involves a thin native oxide layer (~2 nm). The results show that the laser treatment causes an increment in Schottky barrier height (SBH) and decreases leakage currents under a reverse bias voltage of the diode. Notably, we have seen the influence of the laser patterning process on 3D Gr nano-sheets which is that the entire surface of the substrate has now reformed new structures in the nano-sphere and nano-rose morphology, so we believe that this is the first work that shows these structures in this form.

    AtıfScopus14WoS13OpenAlex13
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  • KitapYalnız künye2019
    Selected Topics in Applied Econometrics

    Akay, Ebru Çağlayan; Korkmaz, Özge

    This book aims to bring together studies using different data types (panel data, cross-sectional data and time series data) and different methods (for example, panel regression, nonlinear time series, chaos approach, deep learning, machine learning techniques among others) and to create a source for those interested in these topics and methods by addressing some selected applied econometrics topics which have been developed in recent years. It creates a common meeting ground for scientists who give econometrics education in Turkey to study, and contribute to the delivery of the authors' knowledge to the people who take interest. This book can also be useful for «Applied Economics and Econometrics» courses in postgraduate education as a material source.

    AtıfOpenAlex1
    Scopusİncele
  • MakaleAçık Erişim2022Scopus SJRQ3
    Optimization of lactose derivative hetero-oligosaccharides production using whey as the acceptor molecule by an active glucansucrase

    Kabli, Mohammad; İspirli, Hümeyra; Balubaid, Mohammed; Taylan, Osman; Yılmaz, Mustafa Tahsin; Dertli, Enes

    Glucansucrases are capable of synthesis of distinct oligosaccharides using different acceptor molecules and in this study lactose derivative hetero-oligosaccharides were shown to be produced by an active glucansucrase in its acceptor reaction with sucrose and whey as the donor-acceptor molecules, respectively. Following the monitoring of the reaction products by TLC analysis, the effects of reaction parameters in terms of enzyme concentration, sucrose/whey ratio and reaction temperature on final oligosaccharide yields (OY) were optimized by Response Surface Methodology (RSM). Results indicated that increment of enzyme concentration and reaction temperature decreased the OY in a particular reaction time whereas the OY increased with the increment of sucrose/whey ratio in the acceptor reactions of glucansucrase E81 with whey as the acceptor molecule. A low level of glucansucrase E81 concentration was sufficient to obtain the highest OY in the tested conditions. These findings demonstrated the importance of the optimisation of the reaction parameters for the acceptor reactions of the glucansucrases.

    AtıfScopus2WoS4OpenAlex6
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  • MakaleAçık Erişim2019Scopus SJRQ1
    Transient plane-wave transmission through an N-Layer structure by the method of subregions

    Hasar, Ugur Cem; Kaya, Yunus; Barroso, Joaquim J.

    The temporal transmission properties of an N-layer structure under planar wave incidence are investigated by the method of subregions via the wave matrix approach. The transmission coefficient expression is first expressed in the frequency-domain by reduced transmission coefficients and then transformed into the time domain, which includes unit step functions with different effective time periods and weightings. The analysis is validated by numerical computations and three-dimensional electromagnetic simulations at gigahertz frequencies.

    AtıfScopus12WoS12OpenAlex13
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  • MakaleYalnız künye2020
    THE INVESTIGATION OF FLOW RATE EFFECT ON LEACHATE TREATMENT BY ELECTROOXIDATION PROCESS

    Yilmaz, Alper Erdem; Dede Sağsöz, Yeşim; Sakarya, Merve; Cengız, İbrahim

    In the study, the leachate of the Erzurum Municipality Solid Waste Regular Storage Facility was used. Leaching waters formed in solid waste storage areas and the contents depend on rainfall and the characteristics of the stored waste. The leachate includes a high amount of organic matter it contains, nitrogenous substances, heavy metals, high salinity; it causes pollution of underground and surface receiving environments. Therefore leachate must be treated before being discharged. For this purpose, an electrooxidation process was used for the treatment of leachate. The effect of the flow rate change on the treatment efficiency in the continuous electrooxidation process is investigated. The flow rate was selected as 5, 7.5, and 10 ml/min. The constant current of 20 A was applied with a direct current intensity supply (40 V-250 A) in 600 ml. In the reactor (600 ml) at a constant current of 20 A, the effluent water temperature increased from 15 °C to 31 °C while the pH value was reduced to a value of 8.2 to 4.8. At the constant current of 20 A, approximately 90% chemical oxygen demand (COD) removal was obtained at a flow rate of 5 ml/min, which is the best removal efficiency obtained from flow rate experiments. It is seen from the same study results that the energy consumption value is 55 kWh/m3 at 20 A current and 5 ml/min flow rate. As a result, the electrooxidation process can be used for the treatment of leachate, especially for organic matter removal.

    AtıfScopus2
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  • MakaleYalnız künye2022Scopus SJRQ2
    Lower bounds for blow-up time in a nonlinear parabolic problem with a gradient nonlinearity

    Ayazoglu Mashiyev, Rabil; Ekincioglu, Ismail

    In this article, we study the blow-up properties of solutions to a parabolic problem with a gradient nonlinearity under homogeneous Dirichlet boundary conditions. By constructing an auxiliary function and by modifying the first order differential inequality, we obtain lower bounds for the blow-up time of solutions in Lk(Ω ) (k> 1 ) norm and conditions which ensure that blow-up cannot occur.