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- MakaleYalnız künye2024Scopus SJRQ1A Novel Fuzzy Cumulative Sum Control Chart with an α-Level Cut Based on Trapezoidal Fuzzy Numbers for a Real Case Application
Özdemir, Akın; Uçurum, Metin; Serencam, Hüseyin
Statistical process control (SPC) is widely used to monitor production processes in many industries under certain conditions. When dealing with a quality characteristic for uncertainty, fuzzy numbers are used in the context of the statistical process control (SPC) to monitor a fuzzy production process. The aim of this paper is fourfold. One, a fuzzy X¯-R control chart with an α-level cut is used based on trapezoidal fuzzy numbers (TFNs) for detecting the large shifts in the fuzzy process mean. Second, a fuzzy cumulative sum (FCUSUM) control with an α-level cut based on TFNs is firstly developed for detecting the small shifts in the fuzzy process mean. Third, the fuzzy process capability indices (FPCIs) are presented to measure the fuzzy process performance. Finally, an ultra-fine calcite production process is controlled with both the fuzzy X¯-R control chart and the proposed FCUSUM control chart. The results of the fuzzy X¯-R control charts show that the fuzzy production process is in control, and large shifts in the fuzzy process mean were detected. On the other hand, the results of the FCUSUM charts show that the fuzzy production process is out of control, and small shifts in the fuzzy process mean were detected. FPCIs are also conducted, and the results of fuzzy Cpk indices show that the ultra-fine calcite production process is not capable of meeting specification limits.
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İncele - MakaleAçık Erişim2022Scopus SJRQ1Optimization of Asymmetric Bioreduction Conditions of 2-methyl-1-phenylpropan-1-one by Lactobacillus fermentum BY35 Using I-Optimal Design-Based Model
Aksuoğlu, Selmani; Özdemir, Akın; Serencam, Hüseyin; Dertli, Enes; Şahin, Engin
The bioreduction of prochiral ketones offers efficient access to chiral secondary alcohols, which are potentially beneficial precursors for producing many biologically active compounds and natural products. This bioreduction process can be affected by different parameters when whole-cell of biocatalysts such as Lactic Acid Bacteria strains are applied. In this context, this paper proposed an I-optimal design-based model to optimize culture parameters such as temperature, pH, incubation period, and agitation speed for asymmetric bioreduction of 2-methyl-1-phenylpropan-1-one (1) with Lactobacillus fermentum BY35 as a biocatalyst while achieving the highest conversion rate (cr) and enantiomeric excess (ee). The optimum settings of the four culture parameters and the cr and ee values were found using the proposed optimization model as follows: pH = 6.5, temperature = 25 °C, incubation period = 38.5 h, agitation speed = 200 rpm, the ee value = 98.78%, and the cr value = 98.92%. After the validation of the process, the cr and ee values were found to be > 99% and > 99%, respectively, while using the optimum operating conditions from the optimization model. Thus, the results of the optimization model are consistent with the results of the validation experiment. It is also noted that this paper is the first to optimize culture parameters using the proposed I-optimal design-based model for an asymmetric reduction.
AtıfScopus3WoS3OpenAlex3İncele - MakaleAçık Erişim2021Scopus SJRQ3A novel weighted mean-squared error optimization model to obtain optimal conditions of adsorption factors for a lead removal process
Özdemir, Akın; Teke, Çağatay; Serencam, Hüseyin; Uçurum, Metin; Gündoğdu, Ali
Lead (Pb) removal process from wastewater is an important issue to prevent health problems for people. For this particular purpose, a low-cost adsorbent may be beneficial for improving the adsorption capacity for the Pb removal process. The aims of this paper are four-fold. First of all, a D-optimal experimental design was selected to reduce experimental runs and its cost. Second, the effect of four adsorption design factors, stirring speed (rpm), adsorbent dosage (g), pH level, and initial metal concentration (ppm), was examined. Also, the yellow natural stone, which is from Bayburt, Turkey, was used as a cheap adsorbent for the Pb removal process from the solu-tion. Third, a novel weighted mean-squared error optimization model was developed to obtain optimal adsorption levels for adsorption factors. Besides, a verification study was conducted to verify the results of the adsorption experiment. Finally, the lead (Pb(II)) removal capacity of the yellow Bayburt stone was obtained to be 46.031 mg/g, and the results of the experiment from the proposed methodology showed a good performance for the removal study.
- MakaleAçık Erişim2020Scopus SJRQ1Diversity and functional characteristics of lactic acid bacteria from traditional kefir grains
Purutoğlu, Kübra; İspirli, Hümeyra; Yüzer, Mustafa Onur; Serencam, Hüseyin; Dertli, Enes
Traditional kefir grains were collected from distinct parts of Turkey, and their microbial profile was determined. A wide bacterial biota was observed formed by distinct lactic acid bacteria (LAB) in which Lactococcus lactis strains appeared to be dominant. Yeast species were also identified in kefir grains. Significant levels of antifungal and antibacterial activities were monitored in kefir isolates. All tested LAB produced an exopolysaccharide (EPS) containing glucose and galactose, and some strains formed a fructan-type EPS. Importantly, low levels of antibiotic resistance were observed among the kefir isolates.
AtıfScopus37WoS32OpenAlex44İncele - MakaleYalnız künye2020Scopus SJRQ2Recovery of unburned carbonaceous matter (UCM) from sugar mill bottom ash
Katircioglu-Bayel, Diler; Serencam, Hüseyin; Uçurum, Metin
Millions of tons of coal fly and bottom ash are produced each year in many countries including Turkey. Coal combustion which is the main source of energy in sugar mill and many other industries produce massive quantities of waste. The present study aims to separate the unburned carbonaceous matter (UCM) from the bottom ash of Bor, Nigde-Turkey sugar plant has been studied using the mechanical flotation technique. For this purpose, the performances of three classical oils were investigated and then chemical parameters such as sodium silicate (Na2SiO3), collector (fuel-oil) and frother (pine-oil) were systematically examined by using Yates’ statistical technique. A product with 41.58% combustible grade at 87.44% recovery was obtained at 0 g/t sodium silicate, 7464 g/t fuel-oil, 888 g/t pine-oil, 15% pulp density, 1200 rpm impeller speed and natural pH. The results obtained from the experiments indicated that it was possible to enrich the bottom ash by using conventional flotation.
- MakaleAçık Erişim2019Scopus SJRQ2Modeling design parameters with taguchi experimental method for obtaining operating conditions for cu(Ii) removal through adsorption process
Serencam, Hüseyin; Özdemir, Akın; Teke, Çağatay; Uçurum, Metin
One of the environmental concerns deals with the removal process of pollutants in water and wastewater. In this paper, a removal process was used to eliminate pollutants in water and wastewater. The aim of this paper was to obtain an optimum adsorption condition for the highest metal ions adsorbed (MIA) mg/g. For this particular purpose, a Taguchi L18 design was conducted. In addition, the signal-to-noise ratio was analyzed for optimum adsorption levels. The analysis of variance was also performed to evaluate the effect of each adsorption condition on MIA (mg/g) values. Moreover, an optimization model was also proposed to find the best optimal setting of adsorption levels. Then, the confirmation tests were performed using optimum coded levels of the adsorption parameters for the verification purpose. The results of the experimental study showed a good performance that Cu(II) removal capacity was found to be 43.66 mg/g. To the best of our knowledge, this research is the first to study natural stone as an efficient, inexpensive and cheap adsorbent for the removal process.
AtıfScopus6WoS5OpenAlex6İncele - MakaleAçık Erişim2019Scopus SJRQ3Production of enantiomerically pure (S)-phenyl(pyridin-2-yl)methanol with Lactobacillus paracasei BD101
Şahin, Engin; Serencam, Hüseyin; Dertli, Enes
Asymmetric reduction studies of heteroaryl ketones, including phenyl(pyridin-2-yl)methanone in enantioselective form with biocatalysts are very few, and chiral heteroaryl alcohols have been synthesized generally in the small scale. In this study, seven bacterial strains have been used to produce the (S)-phenyl(pyridin-2-yl)methanol in high enantiomeric excess and yield. Among the tested strains, Lactobacillus paracasei BD101, was found to be the best biocatalyst for the reducing phenyl(pyridin-2-yl)methanone to the (S)-phenyl(pyridin-2-yl)methanol at gram scale. The asymmetric bioreduction conditions were systematically optimized using L. paracasei BD101, which demonstrated excellent enantioselectivity and high level of conversion for the bioreduction reaction. (S)-phenyl(pyridin-2-yl)methanol, which is an analgesic, was produced enantiomerically pure form in the first time on gram scale using a biocatalyst. In total, 5.857 g of (S)-phenyl(pyridin-2-yl)methanol in enantiomerically pure form (>99% enantiomeric excess) was obtained in 52 h with 93% yield using whole cells of L. paracasei BD101. Enantiomerically pure (S)-phenyl (pyridin-2-yl)methanol, which is an analgesic, was first produced in the gram scale using a biocatalyst with excellent ee (>99%) and yield (93%).
AtıfScopus9WoS7OpenAlex9İncele - MakaleAçık Erişim2019Scopus SJRQ3Whole cell application of Lactobacillus paracasei BD101 to produce enantiomerically pure (S)-cyclohexyl(phenyl)methanol
Şahin, Engin; Serencam, Hüseyin; Dertli, Enes
In this study, a total of 10 bacterial strains were screened for their ability to reduce cyclohexyl(phenyl)methanone 1 to its corresponding alcohol. Among these strains, Lactobacillus paracasei BD101 was found to be the most successful biocatalyst to reduce the ketones to the corresponding alcohols. The reaction conditions were systematically optimized for the reducing agent L paracasei BD101, which showed high enantioselectivity and conversion for the bioreduction. The preparative scale asymmetric reduction of cyclohexyl(phenyl)methanone (1) by L paracasei BD101 gave (S)-cyclohexyl(phenyl)methanol (2) with 92% yield and >99% enantiomeric excess. The preparative scale study was carried out, and a total of 5.602 g of (S)-cyclohexyl(phenyl)methanol in high enantiomerically pure form (>99% enantiomeric excess) was produced. L paracasei BD101 has been shown to be an important biocatalyst in asymmetric reduction of bulky substrates. This study demonstrates the first example of the effective synthesis of (S)-cyclohexyl(phenyl)methanol by the L paracasei BD101 as a biocatalyst in preparative scale.
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İncele - MakaleYalnız künye2019Scopus SJRQ3Production of enantiomerically enriched chiral carbinols using Weissella paramesenteroides as a novel whole cell biocatalyst
Tozlu, Caner; Şahin, Engin; Serencam, Hüseyin; Dertli, Enes
In this study, four bacterial strains were tested for their ability to reduce acetophenones to its corresponding alcohol. Among these strains Weissella paramesenteroides N7 was found to be the most successful biocatalyst to reduce the ketones to the corresponding alcohols. The reaction conditions were systematically optimized for W. paramesenteroides N7 that resulted in high enantioselectivity and conversion rates for the bioreduction. The scale-up asymmetric reduction of 1-(4-methoxyphenyl) propan-1-one (1r) by W. paramesenteroides N7 gave (R)-1-(4-methoxyphenyl) propan-1-ol (2r) with 94% yield and >99% enantiomeric excess. This is the first report showing the synthesis of (R)-1-(4-methoxyphenyl) propan-1-ol (2r) in enantiopure form using a biocatalyst on a gram scale. The whole cell catalyzed the reductions of ketone substrates on the preparative scale, demonstrating that W. paramesenteroides N7 would be a valuable biocatalyst for the preparation of chiral aromatic alcohols of pharmaceutical interest as a promising and alternative green approach.
AtıfScopus12WoS10OpenAlex11İncele - MakaleYayıncıda açık erişim2018Scopus SJRQ2Optimization of Adsorption Parameters for Ultra-Fine Calcite Using a Box-Behnken Experimental Design
Uçurum, Metin; Özdemir, Akln; Teke, Çaǧatay; Serencam, Hüseyin; Ipek, Mümtaz
Removal of heavy metals from wastewater is a significant issue because it prevents environmental-based concerns and impacts a large number of diseases and disorders. Many low-cost natural materials have been offered recently as possible precursors to commercial synthetic adsorbents. Ultra-fine calcite, one of these natural materials, has been investigated as a potential commercial adsorbent. Response surface designs are effective experimental techniques to investigate the heavy metal adsorption capacity of ultra-fine calcite. In the present study, one such response surface design, Box-Behnken, is used in order to optimize adsorption factors, such as pH level, initial metal concentration, stirring rate and adsorption time, and to determine the heavy metal capacity of this adsorbent. Our results show that the proposed methodology is an effective approach to optimizing the adsorption process and to maximize the heavy metal capacity.
AtıfScopus9WoS7OpenAlex12İncele - MakaleAçık Erişim2018Scopus SJRQ2Development of cloud point extraction preconcentration of cadmium and lead in solid samples using flame atomic absorption spectrometry
Bahadır, Zekeriyya; Yazar, Murat; Tümay, Süreyya Oğuz; Serencam, Hüseyin; Bektaş, Hakan; Duran, Celal
2-[(6-Morpholin-4-ylpyridin-3-yl)amino]-N’-(4-oxo-3-phenyl-1,3thiazolidin-2-ylidene) acetohydrazide (MPAPTAH) was first used in a cloud point extraction procedure to determine the cadmium and lead ions in solid samples. Triton X-114 was used as a mixed micellar medium. The optimal extraction parameters (e.g. surfactant concentrations, amount of ligand, pH etc.) were evaluated. The optimum experimental conditions for Cd and Pb ions during the extraction procedure were carried out with 0.7 mg of MPAPTAH agent, 1.0 mL 0.2% (w/v) of the surfactant, a pH of 8.0. Under the best analytical parameters, the detection limit (LOD) for Cd(II) and Pb(II) ions were found to be 0.6 μg L−1 and 1.91 μg L−1, while the relative standard deviation (RSD) was taken as 2.78 and 2.86%, respectively. Preconcentration factor (PE) of 50 was obtained from using 50 mL of the sample volume for both ions. The accuracy of the method was tested through analysis of Pb2+ and Cd2+ in certified reference material (CRM Sandy Soil C). The interference effect of certain cations and anions were also investigated. The recoveries of the analyte ions were almost quantitative in the presence of all the interfering ions. Afterwards, the developed method was successfully applied to find lead and cadmium in real solid samples, including black tea, tobacco, and chili pepper.
AtıfScopus9WoS8OpenAlex8İncele - MakaleYalnız künye2014Scopus SJRQ2Synthesis and electrochemistry of metallophthalocyanines bearing {4-[(2E)-3-(3,4,5-trimethoxyphenyl)prop-2-enoyl]phenoxy} groups
Acar, Irfan; Arslan, Tayfun; Topçu, Saim; Aktaş, Ayşe; Şen, Serkan; Serencam, Hüseyin
In this study, metallophthalocyanines 4, 5, 6 was carried out by the cyclotetramerization of 4-{3-[(2E)-3-(3,4,5-trimethoxyphenyl)prop-2-enoyl] phenoxy}phthalonitrile 3. The synthesis of metallo derivatives [Zn(II), Co(II), Cu(II)] of phthalocyanines obtained from corresponding phthalonitrile derivative and in the presence of the anhydrous divalent metal salts (Zn(CH 3COO)2, CoCl2 and CuCl2) was described. These phthalocyanines showed good solubility in organic solvents such as chloroform, tetrahydrofuran, DMSO and DMF. The newly synthesized Pcs were verified by IR, 1H NMR, 13C NMR, UV-vis and MS spectral data. The electrochemical properties of the zinc(II), copper(II) and cobalt(II) phthalocyanines were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. The cobalt complex showed a metal based reduction process, while zinc phthalocyanines were giving ligand based electron transfer processes.
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