36 research outputs found

    Benthic Macroinvertebrate Fauna (Clitellata and Chironomidae) of Lake Limni, Gümüşhane, Turkiye

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    Benthic macroinvertebrate groups, which have adapted to life in a wide variety of aquatic habitats from fresh to saltwater, are often used as bioindicators to determine the status of aquatic ecosys-tems. Streams and lakes face the dangers of pollution due to anthropogenic impact, especially due to recreational uses. So far, a total of 262 protected nature parks have been declared in Türkiye, one of which is Lake Limni, the area under study. Lake Limni is located in the province of Gümüşhane in the Eastern Black Sea Basin. No studies were previously conducted to determine the macroinvertebrate fauna in the lake. To fill this gap, sampling was carried out from 2 stations in 2020 to determine the macroinvertebrate fauna of the lake. As a result of laboratory studies, 25 species belonging to 18 genera were identified. It was determined that the zoobenthic community of the lake consisted of Clitellata and Chironomidae individuals and that the dominant taxon of the lake was Limnodrilus hoffmeisteri from Oligochaeta with 14.71% dominancy. The high population density of Oligochaeta and Chironomidae individuals in the study area and the low species diversity indicate poor water quality. It is also possible to say that the water quality of Lake Limni has changed from eutrophic to hypereutrophic

    Synthesis and properties of 3,4-dihydroquinazoline derivatives

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    Üç bölümden oluşan bu tez, N-substitüye 3,4-dihidrokinazolin türevleriyle ilişkilidir. Sentez edilen yeni bileşikler Şema 1 ve Şema 2 de verilmiştir. Birinci bölüm N-heterosiklik karbenlerin ve kinazolinlerin sentezi, önemi ve uygulamalarına ilişkin genel bir derlemedir. İkinci bölümde, 3,4-dihidrokinazolin (D,E,F) 3,4-dihidrokinazolinyum tuzları ([1-27].HBr), rodyum kompleksleri,{[RhCl(1)(COD)], [RhCl(22)(COD)], [RhCl(1)(CO)2], [RhCl(22)(CO)2]}, ve 3,4-dihidrokinazolin içeren rutenyum(II) komplekslerinin {[(p-cymene)RuCl2(D)], [(p-cymene)RuCl2(E,F)]} sentezine ilişkin deneysel ayrıntılar açıklanmıştır. Üçüncü bölümde, 3,4-dihidrokinazolinyum tuzlarının, bunların rodyum komplekslerinin ve 3,4-dihidrokinazolin içeren rutenyum(II) komplekslerinin karakterizasyonu ve katalitik uygulamaları sunulmuştur. Ayrıca 3,4-dihidrokinazolinyum tuzlarının antimikrobiyal aktivite değerlendirmeleri de bu bölümde verilmiştir. 3,4-Dihidrokinazolin-2-ilidenin (benzen kaynaşık tetrahidropirimidin halkası) katalitik etkinliğini ve elektron verme yeteneğini belirlemek için, farklı benzil- ya da aril- substitüye 3,4-dihidrokinazolinler (D,E,F) ve bu yapıların kinazolinyum tuzları ([1-27].HBr) sentezlenmiş, Heck-Mizoroki tepkimesindeki katalitik aktiviteleri incelenmiştir. Tuzlar bu tepkimede orta dereceden iyi dereceye kadar değişen aktiviteler sergilemişlerdir. v-Vericilik yeteneğinin belirlenmesi için tuzlardan ikisi [RhCl(1)(CO)2] ve [RhCl(22)(CO)2] komplekslerine dönüştürülmüştür. Ayrıca tuzların ([1-21].HBr) Gram-pozitif ve Gram-negatif bakteriler ve bir mantara karşı antimikrobiyal etkinlikleri incelenmiştir. Bunlara ek olarak, tuzların sentezi sırasında oluşan ara ürünler (3,4-dihidrokinazolin-D,E,F), N-koordine rutenyum(II) komplekslerinin sentezinde kullanılmıştır {[(p-cymene)RuCl2(D,E,F)]}. Bu komplekslerin asetofenonun transfer hidrojenesyonu tepkimesinde aktif katalizör oldukları saptanmıştır. [(p cymene)RuCl2(Da)] en etkili katalizör olarak belirlenmiştir

    Synthesis of tetrahydropyrimidinium halides and their properties

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    Bu tez tetrahidropirimidinyum halojenürlerle ilgilidir (1 ve 2) ve üç bölümden oluşmaktadır. Birinci bölümde diazinlere ait temel bilgiler, önemi ve kullanım alanları özetlenmiştir. İkinci bölümde deneysel veriler ayrıntılı biçimde açıklanmıştır. Üçüncü bölümde tetrahidropirimidinyum tuzlarının (LHX) sentezi, yapı aydınlatılması ve Pd(OAc)2 varlığında C-C eşleşme (Suzuki ve Heck) tepkimelerindeki katalitik aktiviteleri incelenmiştir. Bu çalışmada seri halinde simetrik ve asimetrik tetrahidropirimidinyum tuzları LHX (1 ve 2) sentezlenmiştir. Rı -C6H2(CH3)3 -C6H2(CH3)3 -C6H(CH3)4 -C6H(CH3)4 -C6(CH3)5 -C6(CH3)5 2acı 2baı 2abı 2aaı -CH3 -CH3 -C2H5 R -C2H5 -C2H5 -CH3 2bbı 2bcı + Br - N H3C N H3C OR RI 2 (LHX) 1c 1d 1e 1b 1a -CH3 -CH3 -OCH3 -C(CH3)3 R Rı Rıı -OCH3 -H -H -H -H -OCH3 -CH3 -H -H -H -H RI RII N H3C N H3C RI RI RI R R RI RII RII + Cl- 1 (LHX) 1 ve 2ʼnin yapı aydınlatılmasından sonra (IR, 1H NMR ve 13C NMR) tüm tuzların Pd(OAc)2 varlığında (Suzuki ve Heck) eşleşme tepkimelerindeki katalitik aktiviteleri araştırılmıştır. Tuzların katalitik aktiviteleri simetrik tuzlarda c<a<e<b<d ve asimetrik tuzlarda bbı<baı<bcı<abı<aaı<acı sırasında uygun şekilde artmaktadır

    Influence of CH3 substituents on tetrahydropyrimidin-2-ylidene: sigma-donating properties and in situ catalytic activities of precursor salts/Pd(OAc)(2) system for C-C coupling reactions

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    WOS: 000289236800005In this study, symmetrical and non-symmetrical 1,3-dialkyltetrahydropyrimidinium salts (1 center dot HCl and 2 center dot HBr, respectively), bearing two methyl groups at C-5 position of the pyrimidine ring were synthesized and characterized. One of the new salts 1,3-bis(2,4,6-trimethylbenzyl)-5,5-dimethyl-3,4,5,6-tetrahydropyrimidinium tetrafluoroborate (1a center dot HBF4, 1a = 6-Bn*-Me-2) was converted to cis-[RhCl(6-Bn*-Me-2)(CO)(2)] to determine the sigma-donating properties in comparison to those of their 5-membered NHC complexes. Furthermore, the in situ catalytic activities of all salts, in combination with Pd(OAc)(2), were tested for the HeckeMizoraki and SuzukieMiyaura type C-C coupling reactions. In contrast to the expectation, only the substituents on N,N'-atoms were found to play an important role in the catalytic activity. (C) 2011 Elsevier B.V. All rights reserved.Turkish Academy of Science (TUBA)Turkish Academy of Sciences; Ege UniversityEge University [2006/Fen/066]; Technological and Science Council of Turkiye [TUBITAK]Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)We thank Turkish Academy of Science (TUBA) and Ege University Research Fund (2006/Fen/066) for financial supporting of this work and Technological and Science Council of Turkiye [TUBITAK] for a grant. We wish to thank Dr. A. Kinal for modeling studies of compounds

    Producing forest fire susceptibility map via multi-criteria decision analysis and frequency ratio methods

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    Located in the Mediterranean basin, one of the world's leading places in terms of forest fires, Turkey is one of the countries where forest fires are experienced very often due to both natural and socio-economic conditions. The objective of this study is to conduct a forest fire susceptibility analysis within the boundaries of Karabuk Forestry Directorate. This analysis was conducted considering the factors affecting the forest fire risk (elevation, slope, aspect, distance to road lines, distance to settlement, land surface temperature and stand type). The factors used in the study were analyzed using geographic information systems (GIS) techniques and analytic hierarchy process method and frequency ratio method. The forest fire susceptibility map produced was classified in 5 categories including very low, low, moderate, high and very fire susceptibility. In order to see how much the forest fire susceptibility map produced corresponds to reality, the forest fire susceptibility maps and the forest fire inventory map were highly compared, and a 73.92% correspondence was detected according to the multi-criteria decision analysis method, while a 76.42% correspondence was detected in the frequency ratio method. As a result, it was concluded that high- and very high-sensitive areas were dominant in the study area, and the site had a high forest fire potential. Ultimately, this study indicated that GIS could be used as a tool to help make effective decisions during forest fire planning

    Hypoglossal Schwannoma Presenting Only With Headache

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    Hypoglossal schwannoma is a rarely encountered skull base lesion that has generally both intracranial and extracranial parts. This article reports a case of hypoglossal schwannoma that is purely extracranial and presents itself only with persistent headache. Magnetic resonance imaging delineated a mass at the skull base that consisted of both cystic and solid components, consistent with a nerve sheath tumor. Cervical approach was chosen, and the mass was completely removed. Postoperatively, the patient developed hypoglossal nerve palsy because the hypoglossal nerve was sacrificed. Hypoglossal schwannomas are briefly discussed with a literature review
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