Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2010Scopus SJRQ2
    Pre- and post-cyclic loading strength of silica-grouted sand

    Mollamahmutoglu, M.; Yilmaz, Y.

    The aim of this study is to investigate whether there is a loss in the strength of fine- to medium-grained colloidalsilica-grouted sand after cyclic loading. First, the rheological properties of colloidal silica grouts, such as gel time and viscosity, are studied. Then, appropriate colloidal silica grouts (saline solution/colloidal silica suspension ratios of 10%, 15%, 20% and 25% by weight) are selected. The selected colloidal silica grouts are then injected into fine- to medium-grained sand specimens prepared at an overall relative density of 50%. The strength of the grouted sand specimens is determined by unconfined compression tests. The effect of curing period on the strength of the grouted samples is also investigated. After performing cyclic loading tests on grouted sand specimens at different cyclic stress ratios (0, 0.13, 0.26 0.39 and 0.52), it is observed that none of the samples failed or was damaged, and that the colloidal silica grout provides fine- to medium-grained sand with a significant resistance to cyclic deformation. The samples are then subjected to unconfined compression tests, and the results show that the loss in the strength of colloidal-silica-grouted sand is insignificant.

    AtıfScopus38WoS32OpenAlex34
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2010Scopus SJRQ4
    Production of a novel pectin lyase from Bacillus pumilus (P9), Purification and characterisation and fruit juice application

    Nadaroǧlu, Hayrunnisa; Taşkin, Esen; Adigüzel, Ahmet; Güllüce, Medine; Demir, Nazan

    Extracellular pectin lyase (EC 4.2.2.10) was produced by Bacillus pumilus (P9) in solid state fermentation. Pectin lyase enzyme was purified 36.36 fold by using DEAE-cellulose anion exchange column chromatography and characterized. Molecular weight of the enzyme was determined as 25 kDa by using Sephadex G-100 gel filtration chromatography. Purification of enzyme was controlled by SDS-PAGE. The optimum pH and temperature of enzyme was determined as pH 6.0 and 60oC, respectively. Pectin lyase was mostly stable at 40°C. Its' activity deceased in 50% for 1h at 60°C and 40% for 4 h at 50°C. Vmax and KM were calculated respectively as 0.298 mg/mL and 132.6 mol/L*min. The presence of 10 mM concentration of Ca2+, Cu2+, Mn2+, Mg2+, Zn2+, Hg2+, Fe2+ and EDTA, L-cystein, ascorbic acid and -mercaptoethanol significantly enhanced the pectin lyase of the purified enzyme. The purified pectin lyase enzyme was used for getting fruits juices. It was determined that yields of fruits juices significantly improved when it was compared with control.

    AtıfScopus33
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  • MakaleYalnız künye2009
    Malzeme Taşıma Odaklı Planlama için Üretim Sistemlerindeki Tezgah Yerleşim Düzenlerinin Benzetim Analizi ile Karşılaştırılması

    Aksarayli, Mehmet; Altuntas, Serkan

    Günümüzde işletmeler üretim maliyetlerini azaltmak ve verimliliklerinin artırmak için uygun tesis planları yapmak zorundadırlar. Çalışma, üretim sistemlerindeki tesis içi yerleşim problemlerinin çözümüne ulaşmakta kullanılan temel tezgâh yerleşim şekilleri ve ürüne göre yerleşim için önerilen yeni bir yaklaşımı birbirleriyle karşılaştıran bir çalışmadır. Çalışmada özellikle tezgâhlar arasındaki malzeme taşıma süreleri ve bu sürelerin toplam üretim süresi içerisindeki oranları ile ilgilenilmiştir. Buna ek olarak, incelenen tüm tezgâh yerleşim şekillerine göre benzetim modelleri sonucunda elde edilen tezgâhların kullanım yüzdeleri ve ürünlerin üretim miktarları da bu çalışma kapsamında aktarılmıştır. Çalışmada ilk olarak tesis planlamasında kullanılan temel yerleşim şekilleri için bir üretim sistemi tanımlanmıştır. Daha sonra tanımlanan üretim sistemi, her bir yerleşim şekli için tezgâh yerleşimi yapılmıştır. Ardından ürüne göre yerleşim şekli için önerilen yaklaşım aktarılarak üretim sistemi için tezgâh yerleşimi yapılmıştır. Daha sonra tezgâh yerleşim şekilleri "PROMODEL" benzetim yazılımı ortamına aktarılmıştır. Son olarak yapılan analizler ile farklı tezgâh yerleşim şekillerinin malzeme taşıma süreleri ve toplam üretim süresi içerisindeki oranları karşılaştırılmış ve analizlerden elde edilen sonuçlar yorumlanarak aktarılmıştır

    AtıfTR Dizin3
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  • MakaleYalnız künye2009Scopus SJRQ3
    Az bulunan Barbutiidae familyasının (Acari: Actinedida) Türkiye’deki ilk bulgusu: Barbutia anguineus (Berlese)

    Doğan, Salih; Akgül, Güldem Dönel

    A newly recorded mite species, Barbutia anguineus (Berlese), collected from Turkey is herein re-described and figured. This is the first record of the family Barbutiidae in Turkey.

    AtıfTR Dizin3
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  • MakaleYalnız künye2009
    Formation of consumption society and consumer behavior - A comparative application -

    Çınar, Recai; Çubukçu, İhsan

    Basic aim of this study is to appraise consumption understanding of consumer covered by either organizations or mass media tools by the increasing importance of globalization within the terms of “consumption society” and “consumption culture”. There are two parts in the study. In the fist part, the factors affecting consumer’s purchasing behaviours and factors affecting creation of consumer society and consumer culture are considered. In the application part of the study, consumption understandings of consumers, the level of sensitiveness of consumers to the factors that increase consumption and the factors affecting formation of consumption cultere are examined by comparing two seperate studies carried in 1998 and 2008. At he end of the study, we concluded that, consumers of today make up of consumption soceity that depends on consumption objects.

    AtıfTR Dizin32
    TR Dizinİncele
  • MakaleYalnız künye2009
    The Foundation of Scouting in Turkey

    Taskesenlioglu, M. Yasin

    Ottoman Empire officially developed scouting into which it fit a paramilitary structure according to its necessities, it aimed ottoman ( Turkish) youth to be grown up as robust people with healthy bodies. Empire's existence in a state of war during a long time, shrinking of its borders constantly and the army's need of soldiers created the necessity of making the youth to be ready for military service. This need made itself felt thoroughly and was on its peek during the World War I. As a matter of fact, Turkish scouting organization born and as a procedure of pre-draft because of the need for soldiers. This practice stood out first as Ottoman Power Associations and then Ottoman Youth Associations. The associations as mentioned before, were influenced the English scouting experience at first, and then, the German one due to state policies. In particular, Ottoman Youth Associations that were active in most part of the country during the World War I were tried to be reestablished during the Republican Era though they had lost their influence totally in 1920. The paramilitary development of Turkish scouting not only hindered the general and private initiatives but also provided basis for later periods. Scouting in the period starting in 1914 which is the official date of foundation in Turkey, has been revived officially in 1923 after War of Indepedence in spite of the negative effects during the World War I.

  • MakaleYalnız künye2009
    The Comparison of Layout Arrangements for the Material Flow Ordering Planning in Production Systems through Simulation Analysis

    Aksarayli, Mehmet; Altuntas, Serkan

    Enterprises have to make suitable location planning to decrease their product cost and to increase their productivity in our time. The aim of this study is to compare the basic layout types used in arranging inside facility layout with each other by using simulation. Especially in this study, material handling times between machines and ratio of these times in total times were interested. First of all a new production system is designed to the basic layout types used in arranging inside facility layout. And then in the designed production system, machines are arranged for each machine layout types. Machine layout types are transferred to PROMODEL simulation software. Then with the results of analysis, material handling times of different machine layout types and ratio of material handling times in total production time were compared and the results obtained from this analysis were given after commented on this study.

    AtıfWoS7
    Web of Scienceİncele
  • MakaleYalnız künye2009Scopus SJRQ3
    Purification and properties of carbonic anhydrase from bone marrow

    Tasgin, Esen; Nadaroglu, Hayrunnisa; Demir, Yasar; Demir, Nazan

    In this work, the carbonic anhydrase was purified from bovine bone marrow and investigated its kinetic properties. Carbonic anhydrase was purified from bovine bone marrow using affinity chromatography by sepharose 4B-L-tyrosine sulphanilamide. During purification steps, the activity of enzyme was measured using p-nitrophenyl acetate at pH: 7.4. Optimum pH and optimum temperature values for bovine bone marrow carbonic anhydrase were determined and then K m and Vmax values for the same substrate were obtained by means of Linewearver-Burk graphics. The purification degree for bovine bone marrow was calculated. The Vmax, and Km values at optimum pH and at 20 °C for the substrate (p-nitrophenyl acetate) were 120.418 uμmol/L min and 2.409 x 103 mM, respectively. The K1 and I50 values for sulfanilamide, KSCN, NaN3 and acetazolamide were determined in bovine bone marrow carbonic anhydrase.

    AtıfScopus7
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  • MakaleYalnız künye2009Scopus SJRQ2
    First year Turkish science undergraduates' understandings and misconceptions of light

    Yalcin, Mehmet; Altun, Sema; Turgut, Umit; Aggül, Fatma

    The present study aims to identify first year Turkish Science undergraduates' understandings and misconceptions of the concept of light and its propagation. For this purpose, an instrument composed of four open-ended questions was developed by the researchers. The diagnostic test was piloted with twenty students and modifications were made prior to the final administration of the test. The content validity of the test questions was assessed by two physics researchers and one lecturer. These questions were administered to a hundred first year undergraduates (aged 16-18) enrolled in the Science Teacher Training Department in Ataturk University in Turkey. In addition, the semi-structured interviews of 30-40 min were conducted with the four students whose responses involved common misunderstanding. All interview records were transcribed and analysed. The findings showed that undergraduates' understanding of light is poor and also they have important and prevalent misconceptions. Identified misconceptions, some of which have been reported in the literature, are discussed qualitatively. The misunderstandings identified were compared with those in the literature. The results have some implications for teaching light, suggesting that a substantial revision of teaching strategies is needed.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus18OpenAlex24
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  • MakaleAçık Erişim2009Scopus SJRQ3
    The first occurrence of the uncommon family barbutiidae (Acari: Actinedida) in Turkey: Barbutia anguineus (Berlese)

    Doǧan, Salih; Dönel, Güldem

    A newly recorded mite species, Barbutia anguineus (Berlese), collected from Turkey is herein re-described and figured. This is the first record of the family Barbutiidae in Turkey.

    AtıfScopus4WoS3OpenAlex3
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2009
    Misconceptions and alternative concepts in biology textbooks: Photosynthesis and respiration; [Ideas falsas y conceptos alternativos en libros de texto de biología: Fotosíntesis y respiración]

    Kose, Esra Ozay; Pekel, Osman; Hasenekoglu, Ismet

    Textbooks have a specific importance since they are used as the main instruction material. It is important to know that whether commonly used textbooks are adequate in terms of content and presentation. This study was performed to examine whether chapters on "photosynthesis" and "respiration" in the Biology-3 textbooks, that are used in secondary schools in Turkey are sufficient in terms of scientific content or not. We provide examples of the identified misconceptions along with their more acceptable alternatives. As a result, it was determined that biology-3 textbooks are insufficient in respect of scientific content. We recommend that biology-3 textbooks must be improved by correcting the scientific content.

    AtıfScopus12
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  • MakaleAçık Erişim2009Scopus SJRQ3
    Synthesis of two alnustone-like natural diarylheptanoids via 4+3 strategy

    Burmaoǧlu, Serdar; Çelik, Hülya; Göiksu, Süleyman; Maraş, Ahmet; Altundaş, Ramazan; Seçen, Hasan

    The first total synthesis of (4E,6E)-1,7-bis(3,4-dihydroxyphenyl)-hepta-4, 6-dien-3-one and an alternative synthesis of (4E,6E)-1,7-bis(4-hydroxyphenyl)- hepta-4,6-dien-3-one, two natural diarylheptanoids, mainly based on Claisen-Schmidt condensation were described. The crucial steps of the syntheses were the condensation of OH-protected 4-aryl-2-butanones with OH-protected 3-aryl-acrylaldehydes by the in situ enamination and then deprotection of OH groups to give the corresponding natural diarylheptanoids.

    AtıfScopus6WoS5OpenAlex7
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  • MakaleYalnız künye2008
    Investigation of effectiveness of demonstrationsimulation based instruction in teaching energy conservation at 7th grade

    Aggul, Fatma; Yalcin, Mehmet; Acikyildiz, Metin; Sonmez, Erdal

    This study aimed to explore the effect of teaching through demonstrationsimulation on students' achievement of energy conservation in comparison with traditional teaching. The sample consisted of fifty nine 7th grade students from a state primary school in Turkey. In the study, non-equivalent groups pretest-posttest design was used and the data was collected through an achievement test developed by the researchers, Energy Conservation Test. The conservation of energy concept was taught using a demonstration and a simulation in the experimental group and traditional instruction method in the control group. Data collected by the test was statistically assessed applying the analysis of covariance. To explore obviously the class atmosphere in experimental group, it was utilized from the teacher's observation notes and student interviews. The statistical comparison showed that there was a significant difference between groups with respect to students' scores of the test. Moreover, the analysis of the qualitative data indicated that such a class atmosphere supported the constructive and meaningful learning.

    AtıfScopus6
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  • MakaleAçık Erişim2008Scopus SJRQ1
    Comparing the impacts of tutorial and edutainment software programs on students' achievements, misconceptions, and attitudes towards biology

    Kara, Yilmaz; Yeşilyurt, Selami

    The purpose of this study was to investigate the effects of tutorial and edutainment design of instructional software programs related to the "cell division" topic on student achievements, misconceptions and attitudes. An experimental research design including the cell division achievement test (CAT), the cell division concept test (CCT) and biology attitude scale (BAS) was applied at the beginning and at the end of the research. After the treatment, general achievement in CAT increased in favor of experimental groups. Instructional software programs also had the positive effect to the awareness of students' understandings to the general functions of mitosis and meiosis. However, the current study revealed that there were still some misconceptions in the experimental groups even after the treatment. It was also noticed that only using edutainment software program significantly changed students' attitudes towards biology.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus31OpenAlex51
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  • MakaleAçık Erişim2008
    Endurance training attenuates the oxidative stress due to acute exhaustive exercise in rat liver

    Taysi, S.; Oztasan, N.; Efe, H.; Polat, M.F.; Gumustekin, K.; Siktar, E.; Canakci, E.; Akcay, F.; Dane, S.; Gul, M.

    The aim of this study was to investigate whether an 8-week treadmill training attenuates exerciseinduced oxidative stress in rat liver. Male rats were divided into untrained and trained groups. Endurance training consisted of treadmill running at a speed of 2.1 km/h, 1.5 h/day, 5 days a week for 8 weeks. To see the effects of endurance training on acute exhaustive exercise induced oxidative stress, untrained and trained rats were further devided into two groups: animals killed at rest and those killed after acute exhaustive exercise, in which the rats run at 2.1 km/h (10% uphill) until exhaustion. Acute exhaustive exercise increased malondialdehyde level in untrained but not in trained rats. It decreased the activity of glutathione peroxidase and total (enzymatic plus non-enzymatic) superoxide scavenger activity in untrained rats and catalase activity in trained rats. However, it did not affect glutathione S-transferase, glutathione reductase, superoxide dismutase and non-enzymatic superoxide radical scavenger activities in both trained and untrained rats. On the other hand, endurance training decreased glutathione peroxidase and glutathione S-transferase activities. The results suggested that endurance training attenuated exercise-induced oxidative stress in liver, probably by preventing the decreases in glutathione peroxidase and total superoxide scavenger activities during exercise.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus30OpenAlex31
    ScopusPubMedİncele
  • MakaleYalnız künye2008Scopus SJRQ1
    The removal of lignin and phenol from paper mill effluents by electrocoagulation

    Uǧurlu, M.; Gürses, A.; Doǧar, Ç.; Yalçin, M.

    This study aims to investigate the treatment of paper mill effluents using electrocoagulation. Removal of lignin, phenol, chemical oxygen demand (COD) and biological oxygen demand (BOD) from paper mill effluents was investigated at various current intensities by using different electrodes (Al and Fe) and at various electrolysis times (1.0, 2.5, 5.0 and 7.5 min). It was observed that the experiments carried out at 12 V, an electrolysis time of 2 min and a current intensity of 77.13 mA were sufficient for the removal of these pollutants with each electrode. The removal capacities of the process using an Al electrode were 80% of lignin, 98% of phenol, 70% of BOD, and 75% of COD after 7.5 min. Using an Fe electrode the removal capacities were 92%, 93%, 80% and 55%, respectively. In addition, it was found that removal of lignin, phenol, BOD and COD increased with increasing current intensity. In the experiments carried out at different current intensities, higher removal can be explained through a decrease in intra-resistance of solution and consequently an increase at the transfer speed of organic species to electrodes. It was also found that Al electrode performs higher efficiency than Fe electrode except for COD removal. However, the time required for removal of BOD was more than that of COD. The results suggest that electrocoagulation could be considered as an effective alternative to paper mill effluents treatment.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus257OpenAlex275
    ScopusPubMedİncele
  • MakaleYalnız künye2005
    Alan Öğretmeni Yetiştirmede Tezsiz Yüksek Lisans Eğitiminin Sonuçlarının Değerlendirilmesi

    Özkan, Esra; Yalçın, Mehmet; Açıkyıldız, Metin; Bayrak, Ramiz; Doğar, Esra; Gürses, Ahmet

    Eğitim sistemleri, bilim ve teknolojideki hızlı gelişmeler ve toplumun ihtiyaç duyduğu insan gücü çerçevesinde yeniden şekillenmektedir. Öğretmen yetiştirme sistemleri de bu gelişmelerden doğrudan etkilenmekte, programlar, eğitim-öğretim süreçleri ve altyapı bakımından alternatif yaklaşımlar gündeme gelmektedir. Eğitim Fakültelerinin yeniden yapılanması süreci de bu tartışmaların bir sonucu olarak görülebilir. Bu çalışma, tezsiz yüksek lisans eğitimlerini sürdüren kimya öğretmen adaylarının ortaöğretim kimya öğretmenleriyle öğretmenlik mesleğine karşı tutumlarını karşılaştırmak amacıyla yapılmıştır. Araştırmanın örneklemini 2003-2004 yılı güz döneminde tezsiz Yüksek Lisans programına devam eden 36 kimya öğretmen adayı ve 22 ortaöğretim kimya öğretmeni oluşturmaktadır. Veri toplama aracı olarak anket kullanılmıştır (α=0,92). Yapılan anket çalışması sonuçlarından kimya öğretmen adaylarının ortaöğretim kimya öğretmenleriyle öğretmenlik mesleğine yönelik tutumları arasında önemli bir farkın olmadığı tespit edilmiştir.

    AtıfTR Dizin4
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