Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(102)
- Güler, Ömer(69)
- Akkurt, Nevzat(68)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(49)
- Celik, Erkan(45)
- Zengin, Gokhan(40)
- Serdar, Osman(39)
- Kocabaş, Mehmet(37)
- Aslan, Naim(31)
- Baskonus, Haci Mehmet(31)
- Bulut, Hasan(31)
- Mete, Suleyman(31)
- Paksoy, Mehmet Yavuz(30)
- Kök, Mediha(27)
- Ince, Muharrem(26)
- Yildirim, Ozal(26)
- Özkul, İskender(26)
- Sulaiman, Tukur Abdulkadir(25)
- Topal, Murat(25)
- Guler, Omer(24)
- Serin, Faruk(23)
- Benzer, Fulya(22)
- Erten, Fusun(22)
- Alataş, Mevlüt(21)
- Güler, Seval Hale(21)
- Baykal, Duygu Sen(20)
- Taşgın, Yahya(20)
- Kutlu, Banu(19)
- Onat, Onur(19)
- Sahin, Kazim(19)
- Tanyol, Mehtap(19)
- Torğut, Gülben(19)
- Yildirim, Numan(19)
- Kahraman, Gökhan(18)
- Orhan, Cemal(18)
- Say, Yakup(18)
- Susam, Selim Orhun(18)
- Utku, Anıl(18)
Yayınlar
- MakaleYalnız künye2021Scopus SJRQ2Two Medicinal Plants (Alkanna trichophila and Convolvulus galaticus) from Turkey: Chemical Characterization and Biological Perspectives
Mahomoodally, Mohamad Fawzi; Zengin, Gokhan; Sinan, Kouadio Ibrahime; Ak, Gunes; Sadeer, Nabeelah Bibi; Angeloni, Simone; Mustafa, Ahmed M.; Caprioli, Giovanni; Maggi, Filippo; Cakilcioglu, Ugur
The aim of the present study was to quantify selected phenolic compounds, determine antioxidant activity and enzyme inhibitory effects of the aerial parts of Alkanna trichophylla Hub.-Mor. (A. trichophylla) and Convolvulus galaticus Rost.ex Choisy (C. galaticus) extracts prepared by homogenizer-assisted extraction (HAE), maceration (MAC) and infusion techniques. This is the first time such study has been designed to validate the phytochemical composition and bioactivity of these plants. Multivariate analysis was conducted on collected data. Rutin and caffeoylquinic acid derivatives were the most significant compounds in A. trichophylla and C. galaticus, respectively. The highest antioxidant activity of A. trichophylla was mostly exhibited by HAE/methanolic extracts as determined by DPPH, ABTS, FRAP (51.39, 112.70 and 145.73 mg TE/g, respectively) and phosphomolybdenum (2.05 mmol TE/g) assays. However, significant antioxidant activities varied within the extracts of C. galaticus. HAE/methanolic extract of A. trichophylla significantly depressed AChE (2.70 mg GALAE/g), BChE (5.53 mg GALAE/g) and tyrosinase (26.34 mg KAE/g) activities and that of C. galaticus inhibited AChE (2.04 mg GALAE/g), tyrosinase (31.25 mg KAE/g) and α-amylase (0.53 mmol ACAE/g) activities significantly. We concluded that HAE was the most efficient extraction technique as high yield of compounds and promising bioactivities were recorded from extracts prepared. Multivariate analysis showed that types of solvents influenced recovery of compounds and biological activities. This research study can be used as one methodological starting point for further investigation on these plants as all results are clearly promising and open the door to further research challenges such as cytotoxicity evaluation, molecular docking analysis, and more screening of pharmacological actions.
AtıfScopus12OpenAlex10
İncele - MakaleAçık Erişim2021Scopus SJRQ3Ultrasonic assisted turning of AISI 52100 steel using nanoparticle-MQL method
Aǧar, Salih; Tosun, Nihat
High cutting force and high cutting tool-chip interface temperature occur during machining of high strength materials like AISI 52100 by using conventional turning method and this makes to the difficult machining operation. Besides, in conventional turning (CT) of these materials, which has high abrasion resistance and hardness properties, an additional process such as grinding is required to achieve the desired surface quality. Ultrasonic assisted turning (UAT) method has been widely used in the machining industry in recent years, as it exhibits better surface quality, lower cutting forces, and cutting temperature than the CT method. This paper focused on experimentally and statistically determining the effects of different cutting parameters and cooling conditions (dry and minimum quantity lubrication-MQL) on surface roughness, workpiece surface texture, tangential direction cutting force, and cutting tool-workpiece interface temperature in the machining of AISI 52100 material by using UAT and CT methods. The experimental results revealed that significant improvements determined in the cutting forces and the surface roughness occurred in UAT compared to CT in all the cooling conditions. However, the increasing cutting speeds caused to observe higher interface temperature values in dry turning by the UAT method. Variance Analysis (ANOVA) was carried out to determine the significance grade of independent variables on dependent variables. According to ANOVA results, while the cutting speed is the most important factor on the surface roughness and the cutting zone temperature, and the cooling method is the most important factor on the cutting force. The effects of turning methods on corresponding surface topography, including surface defects, were evaluated. It is determined that in the surface topography analysis, feed marks are the main texture of the workpiece in the CT method while micro-level indentations and protrusions occurred on the workpiece surface in the UAT method.
AtıfScopus14WoS12OpenAlex14İncele - MakaleYalnız künye2021Scopus SJRQ1Production of Pectin from Lemon Peel Powder Using Ohmic Heating-Assisted Extraction Process
Çilingir, Seda; Goksu, Ali; Sabanci, Serdal
The ohmic heating process is known as homogeneous, efficient, and rapid heating. In the present study, it was aimed to analyze the extraction of pectin from lemon peel using ohmic heating, to evaluate the specific pectin production coefficient (SPPC, mg/kJ) and compared it with traditional pectin production (TPP). The extraction process was carried out at 3 different temperatures (70–90 °C), 3 different solid:liquid ratios (1:30, 1:40, 1:50 g/ml), 3 different extraction holding times (0–30 min), and a constant pH (pH 2 that adjusted with citric acid). From the results, extraction conditions affected the pectin yield. As the temperature and extraction holding time increased, the pectin yields increased. In general, the 30-min pectin yields of the ohmic heating-assisted extraction (OHAE) process were similar to the pectin yields obtained from the TPP under the same conditions. Performance evaluation of pectin production was made for 90 °C, and energy efficiency was found to be over 69% for 3 different solid to liquid ratios. It has been stated that as an alternative to the TPP method, the OHAE process can be applied.
AtıfScopus50WoS44OpenAlex53İncele - MakaleAçık Erişim2021Scopus SJRQ4Electrochemical Corrosion and Metal Ion Release Protective Efficiency of the Multilayer TaN Coatings on CoCrMo Biomedical Alloy
Aslan, Ali Kemal; Bahçe, Erkan; Güler, Mehmet Sami
CoCrMo alloy is widely used in artificial orthopedic joint applications due to its high mechanical properties. But, high levels of the metal ion release from alloy surfaces cause variable toxic and allergic effects on the patient in vivo use. This case restricts the lifetime of the implant and results in the failure of the artificial joint. In order to enhance the corrosion resistance and to decrease the metal ion release, alloy surface was multilayer-coated by closed field unbalanced magnetron system. The protective efficiency of the coatings was determined by potentiodynamic polarization tests and static immersion tests were performed for 45, 60 and 90 days in the simulated body fluid in order to understand the effect of the coatings on the metal ion release. The metal ion concentrations in the simulated body fluids were determined by using inductively coupled plasma mass spectrometry device. The electrochemical corrosion results showed that the multilayer coatings provided 93 % protective efficiency in terms of corrosion resistance. Multilayer coatings decreased the metal ions release levels significantly, especially Co leaking was decreased approximately 52 times compared to uncoated samples.
AtıfScopus2WoS3OpenAlex1İncele - MakaleAçık Erişim2021Scopus SJRQ1An integrated interval type 2 fuzzy AHP and COPRAS-G methodologies for supplier selection in the era of Industry 4.0
Kayapinar Kaya, Sema; Aycin, Ejder
Supply chain has a very extensive and dynamic structure that incorporates new business models, new customer expectations, market searches and technological developments. With the introduction of Industry 4.0 into supply chain, a rapid and intensive process of digitalization begins to transform every step of supply chain. Supply chain selection is one of the essential decisions in reducing the supply chain cost and improving overall quality of product and services. With the implication of digital technologies and Industry 4.0 on supply chain, the supplier selection process has been significantly changed during the recent years. Companies are willing to need new requirements for their own suppliers in accordance with Industry 4.0 implementations and technologies. This paper aims to identify key criteria to Industry 4.0 technologies and evaluate them to select the right suppliers selection in the era of Industry 4.0. Within the scope of this study attempts to develop an integrated interval type 2 fuzzy AHP and GOPRAS-G methodology to select the appropriate supplier in the face of Industry 4.0 implementations. For this purpose, interval type 2 fuzzy AHP was employed to weight the supplier evaluation criteria and then, Gray COPRAS method has been applied to prioritize suppliers. This paper is to provide practitioners and researchers with insight into how Industry 4.0 strategies influence on supplier selection.
AtıfScopus63WoS51İncele - MakaleYalnız künye2021Scopus SJRQ3Glyphosate disrupts sperm quality and induced DNA damage of rainbow trout (Oncorhynchus mykiss) sperm
Akça, Ayşe; Kocabaş, Mehmet; Kutluyer, Filiz
As a widespread pollutant, glyphosate (GLY) adversely affects the aquatic environment and can impair the reproductive ability and functions of fish. The purpose of the current study was to assess in vitro effect of GLY on rainbow trout (Oncorhynchus mykiss) sperm cells. The sperm cells were exposed to different GLY concentrations (2.5, 5, 10 mg/L). Sperm motility parameters were analyzed with computer assisted sperm analysis. DNA fragmentation (%) was measured by the comet assay using fluorescence microscopy. With increased GLY concentration, sperm motility and duration decreased after exposure. DNA fragmentation (% DNA in tail) in sperm cells was higher in treatments containing GLY than control (p < 0.05). Consequently, sperm cells are sensitive to low doses of GLY, and this can negatively affect natural populations.
AtıfScopus8WoS4OpenAlex5İncele - MakaleAçık Erişim2021Scopus SJRQ2Comparative Toxicity of Alpha and Gamma Iron Oxide Nanoparticles in Rainbow Trout: Histopathology, Hematology, Accumulation, and Oxidative Stress
Gürkan, Mert; Gürkan, Selin Ertürk; Yılmaz, Sevdan; Ateş, Mehmet
In this study, alpha and gamma iron oxide nanoparticles, characterizations, toxic effects after being exposed to rainbow trout (Oncorhynchus mykiss) at 0, 1, 10 and 25 mg/L concentrations for 10 days, and then 10-day recovery period without any nanoparticle exposure were examined for histopathological (kidney, liver and gill), hematological, iron accumulation and potential for oxidative stress (TBARS and GSH). Histopathological damages significant at the exposure of increasing concentrations of both nanoparticles (increase in melanomacrophage aggregations, epithelial tissue deformations, cytoplasmic vacuolizations, fatty changes, necrosis, pyknosis, hyperplasia, hypertrophy, lamellar fusions, capillary dilatations). Gamma nanoparticles were determined to accumulate more than the alpha nanoparticles. The most Fe accumulation was detected in the liver. The findings of oxidative stress parameters showed that both nanoparticles have the potential to generate oxidative stress. It was concluded that the exposure of alpha and gamma nanoparticles at specified concentrations and durations had a toxic effect on rainbow trout and the toxicity of these nanoparticles was similar.
AtıfScopus18WoS12OpenAlex16İncele - MakaleAçık Erişim2021Scopus SJRQ2Electrical investigation on Eu+3- doped copolymer composite system and conventional kinetic analysis
Pıhtılı, Güzin; Biryan, Fatih
Poly(maleic anhydride-co-benzyl methacrylate) copolymer was prepared by using free radical polymerization (FRP) method at 70 °C. The structural characterization of the polymer was accomplished FT-IR, 1H and 13C NMR spectroscopic techniques. P(MA-co-BMA)/ EuCl3 composites were prepared rate of 2%, 5% and 10% (wt/wt). The thermal behavior of pure copolymer was investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Thermal decomposition kinetics of poly(MA-co-BMA) carried out from Flynn–Wall–Ozawa method via TG curves for calculated apparent activation energies. According to FWO; the activation energy (Ea) was estimated as; 185.61 kJ/mol. Dielectric and electrical properties of copolymer/composite systems were investigated against frequency (range from 100 Hz to 20 kHz) at room temperature by using an impedance analyzer. The effect of EuCl3 concentration on dielectric constant, dielectric loss factors, ac conductivity, susceptance (B) and impedance (Z) was investigated. A remarkable increase was observed in dielectric and AC electrical properties were observed with the addition of Eu+3 to the polymer matrix. The B and Z parameters of poly(MA-co-BMA) and composites were investigated depending on frequency at room temperature based on the alternating current (AC).
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2021Influence of particle size, additive ratio and chemical structure of zinc borate on mechanical properties of poly(vinyl chloride)
İpek, Yeliz
Zinc borate (ZB) is a flame retardant and smoke supressant compound of boron. It is widely used to achieve flame resistant polymer composites. Poly(Vinyl Chloride) (PVC) is one of the commercially important polymers that is mostly used for cable insulating, windows, doors, pipes, floorings and toys etc.. On the other hand, PVC releases toxic gases during fire as decomposition products. Zinc borate addition is thought to be a solution for this problem. However, this solution leads a new problem. Zinc borate effects the mechanical properties of the PVC. In the present study, to optimize the contribution of zinc borate, with different formulations (2ZnO·3B2 O3·3.5H2 O and 4ZnO·B2 O3·H2 O), with different additive ratios (1% and 5% by weight) and different particle sizes (nano-sized and micro-sized) were added to the PVC structure and the mechanical and thermomechanical properties of each composite were investigated. Mechanical properties of composites were determined by tensile test, impact test, hardness test while thermomechanical behaviours were detected with dynamic mechanical analysis (DMA). In the perspective of mechanical strength of PVC-ZB composite, additive ratio of ZB was more effective than particle size and chemical formulation of ZB. The additive ratio more than 5% by weight can negatively affect the mechanical strength and quality of the PVC-ZB composite.
AtıfScopus2OpenAlex2
İncele - MakaleAçık Erişim2021Scopus SJRQ2Hospital Preparedness Assessment against COVID-19 Pandemic: A Case Study in Turkish Tertiary Healthcare Services
Gul, Muhammet; Yucesan, Melih
Hospitals play a critical role in providing essential health services to people in the healthcare system. Healthcare systems around the world have faced some issues in responding to patients with various disease severity levels. Nowadays, the world as a whole is combating a pandemic called COVID-19. This pandemic causes an increase in the disease spread with fluctuated patient demand that may affect the hospitals' capacity and overall functioning and risks rising based on hospital site, medical staff, patient, and healthcare process. To deal with the challenges of the COVID-19 pandemic, hospitals must have completed their preparations before these events occur. Therefore, this study proposes an integrated approach based on the decision-making concept with interval-valued spherical fuzzy sets (IVSFSs) to the hospital preparedness assessment problem. A technique for order preference by similarity to ideal solution (TOPSIS) extended with IVSFSs is used to rank hospitals from Turkish tertiary healthcare services. A checklist reported by the World Health Organization (WHO) is adapted to conform to Turkey's COVID-19 pandemic management. Ninety-nine subcomponents of the adapted checklist under ten components are weighted by interval-valued spherical weighted arithmetic mean (IVSWAM) operator. The hospitals in the problem are then ranked concerning these weighted subcomponents. With the proposed approach, a COVID-19 pandemic preparedness index is determined for the observed hospitals. In addition, a separate index based on each main component (component-based ranking) is determined. These indexes are vital indicators in determining in which aspects hospitals are ready and in what aspects hospitals are not prepared for pandemics. The proposed approach can be adaptable and applied by national policymakers in assessing all hospitals of the country against the COVID-19 pandemic.
AtıfScopus45WoS33OpenAlex44İncele - MakaleAçık Erişim2021Scopus SJRQ1Carbon and water balance of an afforested shallow drained peatland in Iceland
Bjarnadottir, Brynhildur; Aslan Sungur, Guler; Sigurdsson, Bjarni D.; Kjartansson, Bjarki T.; Oskarsson, Hlynur; Oddsdottir, Edda S.; Gunnarsdottir, Gunnhildur E.; Black, Andrew
Drainage of peatlands increases the depth of the oxic peat layer and can turn them into a carbon (C) source to the atmosphere. Afforestation of drained peatlands could help to reverse this process since the trees may enhance C sequestration. We followed the C and water dynamics of an afforested drained peatland in S-Iceland during a 2 year period, during which the Black Cottonwood (Populus balsamifera ssp. trichocarpa) plantation was 23–25 year old. Net ecosystem exchange (NEE) of carbon dioxide (CO2) was measured with the eddy covariance method and C pools of trees and ground vegetation were measured using the stock change method. Lateral losses of dissolved and particulated organic C (DOC, POC) were estimated from weekly water-runoff samples. Unexpectedly, the afforested drained peatland was a strong sink of carbon during the two years, with an average NEE value of 714 g C m−2 yr−1. Only 0.5% of the total NEE was lost through lateral DOC and POC transport, leaving 710 g C m−2 yr−1 as the total net ecosystem production (NEP). Ca. 91% of the observed NEP could be explained by the annual biomass increment of the Black Cottonwood trees and 1.3% by the ground vegetation. This means that the remaining 7.5% of the total NEP most likely accumulated in peat soil and litter, contributing to the soil C stocks. The dormant-season CO2 emissions were unexpectedly low, which was explained by a high groundwater level at this drained site outside the ca. 5 months of the active growing season. On average, 66% of the annual measured precipitation was estimated to have evaporated back to the atmosphere. This left 416 mm for potential runoff, which was somewhat lower value than the measured runoff (662 mm). These results indicate that during the age span of ca. 20–25 years, afforestation was a valid method to reverse the expected negative C-balance of this drained grassland pasture in Iceland. Although the site is currently a soil C sink, simulation studies with process models are needed to test whether such sites could remain C sinks when managed for forestry over several tree-stand rotations.
AtıfScopus18OpenAlex21İncele - MakaleYalnız künye2021Scopus SJRQ1Using Ochrobactrum thiophenivorans and Sphingomonas melonis for bioremediation of Imidacloprid
Erguven, Gokhan Onder; Demirci, Ulas
To solve the environmental problems of the pesticides, bioremediation methods are commonly useful for their environment friendly properties. These methods are more cheap, useful and have more advantages for remediate receiving environments In this study, imidacloprid which is one of the selective insecticide in all over the world is chosenfor bioremediation studies with two soil bacteria. The imidacloprid used in the Mediterranean climate for cotton, pistachios, tomatoes, peppers and eggplant cultivation. The bioremediation of this insecticide was investigated via the performance of O.thiophenivorans and S. melonis in agitated culture media. The agricultural soil used for the isolation of these two bacteria was taken from the cotton cultivated agricultural area in Adana province in Turkey. For this purpose, the isolated and enriched bacteria were added to the recommended insecticide concentrations, and the Imidacloprid active material, Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5), Total Organic Carbon (TOC), pH and dissolved oxygen (DO) parameters were determined for two weeks on each day of the study. O. thiophenivorens and S. melonis bioremediate the Imidacloprid insecticide with high efficiency (over 90%). According to these results, it is understood that these bacteria can be preferred in the bioremediation of receiving environments that are contaminated with such pesticides and can be useful for scientists to handle the opposite effects of such persistent organic pollutants and COD, BOD5 and TOC parameters can easily give opinions about decreasing of pesticides like the active materials
AtıfScopus28WoS27OpenAlex30İncele - MakaleAçık Erişim2021Scopus SJRQ1Investigation on the properties of new palm-oil-based polyurethane modified bitumen
Vural Kök, Baha; Aydoğmuş, Ercan; Yilmaz, Mehmet; Akpolat, Mustafa
Polyurethane-derived polymer synthesized by the reaction of 4.4′-diphenylmethane diisocyanate (MDI) with the new modified palm-oil-based polyol was used as an alternative additive to thermoplastic-elastomers, such as styrene–butadienestyrene (SBS), the most commonly used additive. The study aimed to investigate the effect of polyurethane (PU) modification on the rheological and chemical structure of base bitumen. The softening point, rotational viscosity, dynamic shear rheometer (DSR), multi-stress creep recovery (MSCR), bending beam rheometer (BBR), and Fourier transform infrared (FTIR) tests were conducted on the binders. The effects of curing time and temperature, isocyanate/hydroxyl (NCO/OH) molar ratio, and PU content were examined and the best modification conditions were determined. It was found that 24 h curing conditions at 85 °C were sufficient for the formation of PU bonds and these processes increased the rutting parameter of the binder by 256% compared to 1 h curing. At 50 °C and a frequency of 5 Hz, the binder with a 4:1 NCO/OH ratio had 63% more complex modulus than the binder with a 10:1 NCO/OH ratio. The 7 wt% PU modified binder had the same performance level as 4% SBS modification and 10 wt% PU modified binder was one degree higher. Moreover, above 60 °C, all the PU modified binders gave lower phase angles compared to the 4% SBS modified binder. 7 wt% PU modified binder showed similar elastic properties against cracks at low temperatures compared to the 4% SBS modified binder. The use of palm oil in the synthesis of PU presents an environmentally friendly and cost-effective solution compared to the use of petrochemical derivatives.
AtıfScopus56WoS53OpenAlex60İncele - MakaleAçık Erişim2021Scopus SJRQ1A Method to Determine the Most Suitable Initial Conditions of Chaotic Map in Statistical Randomness Applications
Acikkapi, Mehmet Sahin; Ozkaynak, Fatih
The processes and systems in the real world actually contain order and symmetry. Understanding these order and symmetrical behavior has been a common effort of scientists. Chaos theory has been an interesting topic to understand these order and symmetrical behavior. One of the most important reasons for this interest is the rich dynamics of chaotic systems. A remarkable application of these systems is statistical randomness. Especially in random number generator designs based on discrete time chaotic systems, an important design parameter affecting the success of the generator (statistical randomness properties) is the initial conditions of chaotic maps. Obtaining different initial conditions that will meet the statistical requirements is important in terms of generating different random number sequences. In order to determine the initial conditions, an algorithm that updates the initial conditions depending on the number of successful statistical tests is proposed. Although the proposed design approach is similar to a back propagation neural network, it has a unique design approach. The NIST SP 800-22 test suite has been used to analyze the statistical properties of the proposed generator. It is known that the NIST SP 800-22 test suite is a hypothesis test. Therefore, in order to show the success of the proposed method in the best way, various additional analysis studies have been carried out proving that the generator outputs have a uniform distribution. Using the proposed method, six different initial conditions have been determined that provide statistical random properties for the discrete-time chaotic systems known as logistic map and tent map. 1,000,000 bits have been generated using the obtained initial conditions. These bit values are then converted to decimal values between 0-15. It is observed that the obtained numbers have a uniform distribution. These outputs are thought to be applicable in many areas such as games, simulation, modeling, determination of optimization parameters and cryptology. It is shown in a practical application for cryptographic substitution-box designs to examine the success of the outputs.
AtıfScopus34WoS23OpenAlex29İncele - MakaleYalnız künye2021Scopus SJRQ3Determination of the estimated amounts of discarded face masks due to COVID 19 in Turkey
Topal, Murat; Topal, Emine Işıl Arslan
In this study, the estimated amounts of discarded face masks due to COVID 19 were investigated. In this context, the amount of waste face masks was determined separately according to the mask types used (nonwoven, meltblown, and 3-ply, pleated) and the importance of waste face masks was revealed. According to obtained data, the estimated total daily face mask use in Turkey is 72,351,638. The highest amounts of nonwoven, meltblown, and 3-ply face mask waste were determined as 26.88, 36.29, and 43.68 tonnes/day for İstanbul city, respectively. Total amounts of nonwoven, meltblown and 3-ply face mask waste in Turkey were calculated as 144.7, 195.35, and 235.14 tonnes/day, respectively. The top 5 provinces with the highest amount of waste masks are listed as follows; İstanbul (nonwoven=26.88, meltblown=36.29, 3ply=43.68 tonnes/day), Ankara (nonwoven=9.91, meltblown=13.38, 3ply=16.11 tonnes/day), İzmir (nonwoven=7.76, meltblown=10.47, 3ply=12.61 tonnes/day), Bursa (nonwoven=5.40, meltblown=7.29, 3ply=8.78 tonnes/day), and Antalya (nonwoven=4.45, meltblown=6.01, 3ply=7.23 tonnes/day), respectively. In Turkey, 91.3% of medical waste collected in health institutions in 2019 (90,920 tonnes) was sterilized and disposed of in storage areas (83,010 tonnes). 8.7% of medical waste was sent to incineration facilities and disposed (7,910 tonnes). Considering these values, 132, 178.35, and 214.7 tonnes/day of nonwoven, meltblown, and 3-ply face mask wastes can be disposed by sterilization and the remaining 12.7, 17, and 20.44 tonnes/day by incineration, respectively.
AtıfScopus5OpenAlex4İncele - MakaleYalnız künye2021Scopus SJRQ2Alternative α* Parameter Estimation for Simplified Beerkan Infiltration Method to Assess Soil Saturated Hydraulic Conductivity
Yilmaz, D.
Abstract: In situ characterization of the saturated hydraulic conductivity (Ks) requires a large number of experiments, sampling, and laboratory measurements that are time-consuming and expensive. Simplified Beerkan Infiltration (SBI) method was developed to estimate an approximate Ks based on the infiltration curve without any sampling procedures. For that purpose, α* parameter, which is used in the calculation of Ks, was commonly set to a fixed value based on soil texture. This approach was not sufficient for an accurate Ks estimation. For a relatively dry soil, a new approach involving an empirical structural parameter was proposed to calculate an approximation of the α* parameter based on the shape of the steady state asymptote of the Beerkan cumulative infiltration. The new α* parameter was tested on simplified Beerkan infiltration (SBI) method in over 32 Beerkan experiments selected from the Soil World Infiltration Global (SWIG) database. The steady state SBI (SSBI) method estimated Ks with an accuracy close to those estimated with the BEST (Beerkan Estimation Soil Transfer) method. The R2 correlation factor for the SSBI method in Ks estimation with BEST intercept and steady methods were 0.982 and 0.994, respectively. For the transient SBI method, the R2 correlation factors calculated with BEST methods were lower; 0.858 and 0.827, respectively. Therefore, the application of the new α* parameter to the steady state simplified Beerkan approach allows an easy, inexpensive way to estimate accurately Ks.
AtıfScopus6WoS6OpenAlex11İncele - MakaleYalnız künye2021Scopus SJRQ2Radiation shielding and mechanical properties of Bi2O3–Na2O–TiO2–ZnO–TeO2 glass system
Sayyed, M.I.; Askin, Ali; Zaid, M.H.M.; Olukotun, S.F.; Khandaker, Mayeen Uddin; Tishkevich, Daria I.; Bradley, D.A.
Recently, heavy metal oxides (HMO) based glass systems attracted great attention to the scientific community to be used as an alternative to the conventional lead, lead composites and concrete based materials for protection of harmful radiation. In this work, we report the role of Bi2O3 on the mechanical and radiation shielding properties of Bi2O3–ZnO–TiO2–Na2O–TeO2 glass system as well as its mechanical behaviour. The mechanical properties of the glasses were calculated using Makishima-Mackenzie model and different shielding factors have been calculated using Monte Carlo simulation via Geant4 code and also using Phy-X software. The mechanical properties based on Makishima-Mackenzie model depend on the values of packing density (Vi) and dissociation energy (Gi) of the oxide constituents. The simulated values of the mass attenuation coefficient showed a good agreement between both approaches. The mass attenuation coefficient (MAC) at 0.284 MeV of the glass with 5 mol% of Bi2O3 is equal to 0.2083 cm2/g, at 0.662 MeV its equal to 0.0785 cm2/g, while at 1.33 MeV, its MAC is 0.0501 cm2/g. The transmitted percentage of the photons through the proposed glasses was found to rise with increasing the energy of the photon, while decreasing with rising the thickness of the glass sample. The transmission factor (TF) revealed that the greater the thickness of the glass, the lower the TF, and the better the shield. Also, the radiation protection efficiency of the glasses was enhanced with the addition of the Bi2O3. The glass sample with composition of 15Bi2O3–10ZnO–5TiO2–5Na2O–65TeO2 possesses the highest effective atomic number among the studied compositions and showed the lowest half value layer. From the obtained data, Bi2O3 seems to be a strong candidate for enhancing the gamma radiation attenuation factors in the bismuth-based tellurite glasses.
AtıfScopus77OpenAlex78İncele - MakaleYalnız künye2021Scopus SJRQ3Effects of iron powder on properties of geopolymers subjected to different curing regimes
Gulmez, Nihan; Kockal, Niyazi Ugur
Silica fume, slag and iron powder are by-products from various industries. In parallel with development of industrial technology, it is also known that these by-products which cause rapid pollution of the environment are also harmful to human health because they are easily respirable. For this reason, a series of experiments were carried out to determine physical and mechanical properties on samples prepared using different blend designs to examine the effect of factors such as curing conditions, binder type and waste iron powder content. Percentages of iron powder added to replace the aggregate are 10%, 20%, 30% and 40% by volume of slag aggregate. It was observed that the substitution of 30% by volume iron powder instead of slag in geopolymer mortars is the most effective in increasing splitting tensile strength. For 40% partial replacement of fine aggregates with iron powder, increases in compressive strength and flexural strength of slag-based mortars were 7.2% and 43.4%, respectively, compared to mortar without iron powder at 60°C curing conditions.
AtıfScopus4İncele - Kitap BölümüYalnız künye2021“An International Crossroads of Female Pain”1 Intersectional Feminism: Jackie Kay’s Chiaroscuro
Doğan, Pelin
- MakaleAçık Erişim2021Scopus SJRQ2Lycopene ameliorates propionic acid-induced autism spectrum disorders by inhibiting inflammation and oxidative stress in rats
Erten, Fusun
This study was conducted to study lycopene efficacy in brain-behavior, pro-inflammatory and apoptotic markers, and antioxidant levels in a rodent model. Rats were administered with propionic acid (PPA) (500 mg/kg BW) to induce autism-like disorders, then treated with different lycopene (L) concentrations (5, 10, 20 mg kg−1 day−1) for 35 days. The groups were: (i);control, (ii);PPA, (iii);PPA + L5, (iv);PPA + L10, and (v);PPA + L20. In this study, serum and brain malondialdehyde (MDA) levels decreased with lycopene supplements compared to the PPA group, similarly to the brain levels of inflammatory factors (IL-1α, IL-8, NF-κB, TNF-α; p <.05). Besides, brain levels of anti-apoptotic Bcl-2 decreased, whereas pro-apoptotic Bax, antioxidant Nrf2, and HO-1 levels in brain increased compared with PPA (p <.05). This study showed that lycopene might have therapeutic value to improve the dysfunctions in learning and memory in a dose-dependent way, along with the antioxidant, anti-inflammatory, and antiapoptotic molecular responses in a rat model of ASD-like disorders. Practical applications: This study suggested that lycopene can reduce propionic acid (PPA)-induced learning and memory impairment and oxidative damage by participating in multiple biological activities such as antioxidant, and anti-inflammatory effects. Lycopene protects serum and brain tissues against PPA induced oxidative damage in rats. These effects may be realized through up-regulation of the brain Nrf2/HO-1 pathway and down-regulation of the IL-1α, IL-8, TNF-α, and NF-κB levels. Lycopene may also contribute to memory and learning function, apoptotic/antiapoptotic modulation, and antioxidant and possible therapeutic efficacy in PPA-induced- Autism spectrum disorder cases.
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