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Asymmetric Synthesis Of 8-O-4'-Neolignan Perseal B, Yamu Xia, Wei Wang, Yinglan Guo, Junfeng Li
Asymmetric Synthesis Of 8-O-4'-Neolignan Perseal B, Yamu Xia, Wei Wang, Yinglan Guo, Junfeng Li
Turkish Journal of Chemistry
Full details of an enantioselective total synthesis of 8-O-4'-neolignan perseal B are presented for the first time. The synthesis was achieved in 8 steps from vanillin and involved the asymmetric dihydroxylation reaction using AD-mix-\alpha to give the key intermedium (1S,2S)-1-(4-(benzyloxy)-3-methoxyphenyl)propane-1,2,3- triol, and the Mitsunobu reaction between phenylpropanoid and vanillin formed perseal B. The synthetic method of perseal B exhibits a new route for 8-O-4'-neolignan.
Mannich Base Derivatives Of 3-Hydroxy-6- Methyl-4h-Pyran-4-One With Antimicrobial Activity, Demet Us, Barkin Berk, Eni̇se Ece Gürdal, Ni̇han Ayteki̇n, Zühtü Tanil Kocagöz, Berrak Çağlayan, Işil Kurnaz, Di̇lek Demi̇r Erol
Mannich Base Derivatives Of 3-Hydroxy-6- Methyl-4h-Pyran-4-One With Antimicrobial Activity, Demet Us, Barkin Berk, Eni̇se Ece Gürdal, Ni̇han Ayteki̇n, Zühtü Tanil Kocagöz, Berrak Çağlayan, Işil Kurnaz, Di̇lek Demi̇r Erol
Turkish Journal of Chemistry
A series of 3-hydroxy-6-methyl-2-[(substitutedpiperidine-1-yl) methyl]-4H-pyran-4-one structured compounds were synthesized by reacting 5-hydroxy-2-methyl-4H-pyran-4-one with suitable piperidine derivatives using Mannich reaction conditions. Antibacterial activities of the compounds for E. coli ATCC 25922, S. paratyphi ATCC BAA-1250, S. flexneri ATCC 12022, E. gergoviae ATCC 33426, and M. smegmatis ATCC 14468 were assessed in vitro by the broth dilution method for determination of minimum inhibitory concentration (MIC). In addition, their inhibitory effects over DNA gyrase enzyme were evaluated using a DNA gyrase supercoiling assay. All the synthesized compounds showed a MIC value of either 8 or 16 \mu g/mL for M. smegmatis, whereas minimum …
Preparation Of Polystyrene/Montmorillonite Nanocomposites: Optimization By Response Surface Methodology (Rsm), Sadik Erdem Yalçinkaya, Nuray Yildiz, Mehmet Saçak, Ayla Çalimli
Preparation Of Polystyrene/Montmorillonite Nanocomposites: Optimization By Response Surface Methodology (Rsm), Sadik Erdem Yalçinkaya, Nuray Yildiz, Mehmet Saçak, Ayla Çalimli
Turkish Journal of Chemistry
Preparation of polystyrene (PS)-montmorillonite nanocomposites was carried out in 3 steps: purification and determination of the cation exchange capacity (CEC) of clay, synthesis of organoclay, and preparation of nanocomposites. In organoclay synthesis, 3 types of surfactants, long-chained (cetyltrimethylammonium bromide (CTAB)), short-chained (tetraethylammonium bromide (TEAB)), and ringed (benzyltriethylammonium bromide (BTEAB)), were used. Gallery distances of pure clay and organoclays (CTAB-O, TEAB-O, and BTEAB-O) were determined by X-ray diffraction (XRD) analysis as 1.25, 2.09, 1.52, and 1.63 nm, respectively. Preparation of nanocomposites was carried out by in situ polymerization. Composites, containing 2%, 4%, and 6% organoclay by mass, were characterized by XRD, …
Synthesis, Spectroscopic Characterization, Mass Spectrometry, And Crystal Structure Of N-{[(4-Bromophenyl)Amino]Carbonothioyl}Benzamide, Sohail Saeed, Naghmana Rashid, Moazzam Bhatti, Peter Jones
Synthesis, Spectroscopic Characterization, Mass Spectrometry, And Crystal Structure Of N-{[(4-Bromophenyl)Amino]Carbonothioyl}Benzamide, Sohail Saeed, Naghmana Rashid, Moazzam Bhatti, Peter Jones
Turkish Journal of Chemistry
N-{[(4-bromophenyl)amino]carbonothioyl}benzamide was synthesized and characterized by IR, ^1H- and ^{13}C-NMR, mass spectrometry, and elemental analysis. The crystal structure was determined from single crystal X-ray diffraction data. It crystallizes in monoclinic space group P2_1/n with unit cell dimensions a = 13.822(3) Å, b = 5.927(2) Å, c = 16.642(3) Å, and \beta = 103.963(3)°. There is a strong intramolecular hydrogen bond of the type N__H \Lambda O, with an H\Lambda O distance of 2.6129 (11) Å. The mass fragmentation pattern is also discussed.
Synthesis And Crystal Structure Of A Novel Multimodal Ligand, 6,6'-Bis(2-(Di(Pyridin-2-Yl)Methylene)-1-Methylhydrazinyl)-2,2'-Bipyridine, And Its Copper(I) Complex, {[Cu_3l_2](Pf_6)_3° 3h_2o} (1), Çağlar Ağaç, İsmai̇l Yilmaz, Abdurrahman Şengül, Simon J. Coles
Synthesis And Crystal Structure Of A Novel Multimodal Ligand, 6,6'-Bis(2-(Di(Pyridin-2-Yl)Methylene)-1-Methylhydrazinyl)-2,2'-Bipyridine, And Its Copper(I) Complex, {[Cu_3l_2](Pf_6)_3° 3h_2o} (1), Çağlar Ağaç, İsmai̇l Yilmaz, Abdurrahman Şengül, Simon J. Coles
Turkish Journal of Chemistry
The single crystal X-ray structure of the novel multimodal ligand 6,6'-bis(2-(di(pyridin-2-yl)methylene)-1-methylhydrazinyl)-2,2'-bipyridine, C_{34}H_{28}N_{10} (L), was determined at 120 (2) K. The ligand possesses a centre of symmetry that generates a planar bipyridyl core with the hydrazone substituents in a trans-geometry. The di-2-pyridyl moieties at either terminus of the molecule twist out of the plane (52.90 and 56.32 Å). The crystal structure comprises 2-dimensional ribbons that stack about each other so as to optimise van der Waals interactions and packing efficiency. Studies of the coordination properties of the novel multimodal ligand with copper(I) show that 2 ligand strands wrapped around the copper(I) …
An Efficient And Green Approach For The Synthesis Of Vinyl Aryl Ethers In The Presence Of Guanidine Hydrochloride, Seyed Mohammad Vahdat, Robabeh Baharfar
An Efficient And Green Approach For The Synthesis Of Vinyl Aryl Ethers In The Presence Of Guanidine Hydrochloride, Seyed Mohammad Vahdat, Robabeh Baharfar
Turkish Journal of Chemistry
A stereoselective procedure for vinyl aryl ether bond formation by direct coupling of dialkyl acetylenedicarboxylates and substituted phenols or naphthols under mild reaction conditions has been developed. Using guanidine hydrochloride as a new catalyst and water-acetone as green solvent, dialkyl acetylenedicarboxylates were reacted with substituted phenols or naphthols in room temperature to produce vinyl aryl ethers in good to excellent yields.
Synthesis And Surfactant Properties Of N-Acylation Compounds Derived From Hydrolysis Degradation Products Of N-(\Beta-Cianoethyl)-\Epsilon-Caprolactam, Andreea Bondarev
Synthesis And Surfactant Properties Of N-Acylation Compounds Derived From Hydrolysis Degradation Products Of N-(\Beta-Cianoethyl)-\Epsilon-Caprolactam, Andreea Bondarev
Turkish Journal of Chemistry
N-acyl amino acids can be used as active surface agents in the detergents industry, as well as in the pharmaceutical industry and cosmetics. Properties of these compounds are superior to those of fatty acids soaps and they are not toxic to the environment and have low Kraft points, because of peptide bonds (CO-NH). Acylation at the nitrogen atom can be performed with good yields without catalysts, for strong nucleophilic derivatives. The synthesis of some derivatives of 4-azasebacic acid, which are hydrolysis degradation products from N-(\beta -cianoethyl)-\epsilon -caprolactam, has been described and the N-acylation processes for these compounds are also presented. …
Synthesis And Characterization Of Ba/Mcm-41, Emi̇ne Kaya, Nuray Oktar, Gürkan Karakaş, Kirali̇ Mürtezaoğlu
Synthesis And Characterization Of Ba/Mcm-41, Emi̇ne Kaya, Nuray Oktar, Gürkan Karakaş, Kirali̇ Mürtezaoğlu
Turkish Journal of Chemistry
Mesoporous Ba/MCM-41 type materials (Ba/MCM-41) with high Ba/Si molar ratios between 0.025 and 0.1 were synthesized by direct hydrothermal synthesis. The samples were characterized by XRD, nitrogen adsorption, TGA-DTA, FTIR, SEM-EDS, and TEM techniques. BET surface areas of samples with various Ba loadings were found between 722 and 931 m^2/g with 28 Å average pore size, which is consistent with the pore size of 30 Å for pure MCM-41 samples synthesized by the same procedure. The crystal structures of synthesized MCM-41 and Ba/MCM-41 were confirmed by XRD analysis. Among the investigated Ba/MCM-41 samples, the formation of barium oxide and barium …
Comparative Essential Oil Analysis Of Geranium Sylvaticum Extracted By Hydrodistillation And Microwave Distillation, Nuran Kahri̇man, Gonca Tosun, Hasan Genç, Nuretti̇n Yayli
Comparative Essential Oil Analysis Of Geranium Sylvaticum Extracted By Hydrodistillation And Microwave Distillation, Nuran Kahri̇man, Gonca Tosun, Hasan Genç, Nuretti̇n Yayli
Turkish Journal of Chemistry
The essential oil of Geranium sylvaticum L. (Geraniaceae) was isolated by hydrodistillation (HD) and microwave distillation (MD). The composition of the volatile oils was characterized by GC-FID and GC-MS. A total of 73 and 70 compounds were identified, constituting over 90.3% and 98.7% of oil composition of G. sylvaticum, respectively. Sesquiterpene hydrocarbons were shown to be the main group of constituents (HD: 31.7% and MD: 39.8%). The major component of the oils of G. sylvaticum was \gamma -muurolene (HD: 10.9% and MD: 19.6%). The comparative study showed that the amount of total volatiles (98.7%) and the major constituent (39.8%) were …
Influence Of The Nitrogen Concentration On The Electrical Characteristic Of Hydrogenated Amorphous Silicon Nitride (A-Sin_X:H) Based Schottky Diodes, İlker Ay, Hüseyi̇n Tolunay
Influence Of The Nitrogen Concentration On The Electrical Characteristic Of Hydrogenated Amorphous Silicon Nitride (A-Sin_X:H) Based Schottky Diodes, İlker Ay, Hüseyi̇n Tolunay
Turkish Journal of Physics
In this study, the Schottky diode characteristic of hydrogenated amorphous silicon nitride (a-SiN_x:H) samples containing various amounts of nitrogen have been investigated via both I-V and C-V measurements. From forward bias I-V measurements in the dark, the barrier height of samples (\phi_{B0}), ideality factor (\eta ), modified Richardson constant (A^\ast) and series resistances (R_s) have been obtained as the function of temperature for different nitrogen content. In addition, forward and reverse bias current ratios (I_f/I_r) at V~=~1 volt have been investigated as the function of temperature for different nitrogen content. Light sensitivity of the samples has also been investigated under …
Photocurrent And Surface Recombination Mechanisms In The In_Xga_{1-X}N\Slashgan Different-Sized Quantum Dot Solar Cells, Hossein Movla, Foozieh Sohrabi, Jafar Fathi, Hassan Babaei, Arash Nikniazi, Khadije Khalili, Nima Es'haghi Gorji
Photocurrent And Surface Recombination Mechanisms In The In_Xga_{1-X}N\Slashgan Different-Sized Quantum Dot Solar Cells, Hossein Movla, Foozieh Sohrabi, Jafar Fathi, Hassan Babaei, Arash Nikniazi, Khadije Khalili, Nima Es'haghi Gorji
Turkish Journal of Physics
We present a p-i-n structured solar cell with stacked layers of In_xGa_{1-x}N Quantum Dots (QDs) with different indium composition. The photocurrent and surface recombination processes are investigated in the i-region. We have shown that the QDs in the i-region can play the role of both generation or recombination centers. The photocurrent has been calculated by self-consistent method to solve continuity equation of charge carriers in the layers of the i-region. By changing the Indium composition in In_xGa_{1-x}N QDs, the band gap of QDs varies and therefore provides a considerable overlapping with solar spectrum. Proposed SC with different-sized QDs and different …
Linear-Like Discrete-Time Fuzzy Control In The Regulation Of Irrigation Canals, Ömer Faruk Durdu
Linear-Like Discrete-Time Fuzzy Control In The Regulation Of Irrigation Canals, Ömer Faruk Durdu
Turkish Journal of Agriculture and Forestry
A linear-like discrete-time fuzzy controller was designed to control and stabilize a single-pool irrigation canal. Saint Venant equations for open-channel flow were linearized using the Taylor series and a finite-difference approximation of the original nonlinear partial differential equations. Using the linear optimal control theory, a traditional linear quadratic regulator (LQR) was first developed for an irrigation canal with a single-pool, and the results were observed. Then a linear-like global system representation of a discrete-time fuzzy system was proposed by viewing a discrete-time fuzzy system in a global concept and unifying the individual matrices into synthetic matrices. This linear-like representation aided …
Impact Of Irrigation Water Quality, Irrigation Systems, Irrigation Rates And Soil Amendments On Tomato Production In Sandy Calcareous Soil, Abdulrasoul M. Al-Omran, A. R. Al-Harbi, Mahmoud A. Wahb-Allah, Mahmoud Nadeem, Ali Al-Eter
Impact Of Irrigation Water Quality, Irrigation Systems, Irrigation Rates And Soil Amendments On Tomato Production In Sandy Calcareous Soil, Abdulrasoul M. Al-Omran, A. R. Al-Harbi, Mahmoud A. Wahb-Allah, Mahmoud Nadeem, Ali Al-Eter
Turkish Journal of Agriculture and Forestry
Low quality water for irrigation can impose a major environmental constraint to crop productivity. Effects of water quality, irrigation system, irrigation rates, and type of amendment on the yield and quality of tomato plants were investigated during the 2 growing seasons of 2005/2006 and 2006/2007. Two water quality treatments (fresh water with electrical conductivity (EC) of 0.86 dS m^{-1}, and saline water with EC of 3.6 dS m^{-1}), 2 drip irrigation systems (surface and subsurface), 3 irrigation rates (2, 4, and 6 L h^{-1}) and 3 amendment types (clay deposit, and organic matter and without amendment) were applied. The results …
Evaluation Of Fertilizing Schemes For Direct-Seeding Rice Fields In Taihu Lake Basin, China, Yong Li, Lin Zhang Yang, Chao Wang
Evaluation Of Fertilizing Schemes For Direct-Seeding Rice Fields In Taihu Lake Basin, China, Yong Li, Lin Zhang Yang, Chao Wang
Turkish Journal of Agriculture and Forestry
Field experiments were performed to identify an effective fertilizing scheme for direct-seeding rice (DSR) fields in the Taihu Lake Basin in east China. Based on local traditions, 3 typical fertilizing schemes (FS-1, FS-2, and FS-3) were evaluated, in consideration of ensuring a certain rice yield and relatively low nitrogen (N) loss. The base, seedling, tillering, jointing, and panicle fertilizers for FS-1 were all 20% of 270 kg N ha^{-1}, those for FS-2 were 30%, 30%, 0%, 25%, and 15% of 270 kg N ha^{-1}, and 15%, 20%, 25%, 20%, and 20% of 220 kg N ha^{-1} for FS-3, respectively. The …
Determination Of Gene Escape And Fruit Quality Characteristics In Transgenic Melon (Cucumis Melo L. Var. Inodorus), Yeşi̇m Yalçin Mendi̇, Nebahat Sari, Asi̇ye Akyildiz, İlknur Solmaz, Ceren Ünek, Okan Özkaya, Sedat Serçe
Determination Of Gene Escape And Fruit Quality Characteristics In Transgenic Melon (Cucumis Melo L. Var. Inodorus), Yeşi̇m Yalçin Mendi̇, Nebahat Sari, Asi̇ye Akyildiz, İlknur Solmaz, Ceren Ünek, Okan Özkaya, Sedat Serçe
Turkish Journal of Agriculture and Forestry
Gene escape and fruit quality characteristics of transgenic melons (Cucumis melo L. var inodorus cv. 'Kirkagac 637') resistant to zucchini yellow mosaic virus (ZYMV) and control plants were investigated under screenhouse conditions. No significant differences were observed between transgenic and transgenic × control genotypes, with regard to rind thickness, fruit cavity length, fruit cavity width, total soluble solids, pistil scar diameter, and peduncle length. Fruit characters, including fruit weight, fruit width, fruit length, fruit flesh thickness, and peduncle diameter were significantly different. These results indicate that transgenic × control genotypes had higher values than transgenic (T4 and T20) genotypes, regarding …
Certain Physical And Mechanical Properties Of Medium Density Fiberboards Manufactured From Blends Of Corn (Zea Mays Indurata Sturt.) Stalks And Pine (Pinus Nigra) Wood, Mehmet Akgül, Cengi̇z Güler, Yalçin Çöpür
Certain Physical And Mechanical Properties Of Medium Density Fiberboards Manufactured From Blends Of Corn (Zea Mays Indurata Sturt.) Stalks And Pine (Pinus Nigra) Wood, Mehmet Akgül, Cengi̇z Güler, Yalçin Çöpür
Turkish Journal of Agriculture and Forestry
Corn stalk is a renewable natural resource that currently has limited industrial utilization. The objective of this study was to examine some chemical properties of corn stalk (holocellulose, \alpha-cellulose, lignin and ash content, alcohol-benzene, hot and cold water solubility, and solubility in dilute alkali [1% NaOH]) and to evaluate its suitability for medium-density fiberboard (MDF) production. Panels were produced using mixtures of corn stalk (Zea mays indurata Sturt.) and pine (Turkish Pinus nigra) fibers in various proportions (from 0% to 100%). The panels produced had density levels of 0.6, 0.7, and 0.8 g cm^{-3}. The physical and mechanical properties of …
Effects Of Cultural Practices On Weed Flora In Virginia (Flue-Cured) Organic Tobacco (Nicotiana Tabacum L.): Green Manure And Irrigation Systems, Anestis Karkanis, Dimitrios Bilalis, Aspasia Efthimiadou, Panagiotis Efthimiadis
Effects Of Cultural Practices On Weed Flora In Virginia (Flue-Cured) Organic Tobacco (Nicotiana Tabacum L.): Green Manure And Irrigation Systems, Anestis Karkanis, Dimitrios Bilalis, Aspasia Efthimiadou, Panagiotis Efthimiadis
Turkish Journal of Agriculture and Forestry
Organic tobacco is a new industrial crop. Field experiments were conducted, during 2005-2006, to determine the effects of irrigation system and green manure on weed flora in organic tobacco crops (Nicotiana tabacum cv. NC 71). The experiments were designed as a split plot design with 4 replicates, 2 main plots (drip and sprinkler irrigation), and 3 sub-plots (vetch and red clover as green manure, and control). The greatest number and dry weight of weeds was observed in sprinkler irrigation. Our results indicate that weed distribution under drip and sprinkler irrigation is related not only to the surface soil water content …
Pathogen Reduction Effects Of Solar Drying And Soil Application In Sewage Sludge, Nurtaç Öğleni̇, Sai̇m Özdemi̇r
Pathogen Reduction Effects Of Solar Drying And Soil Application In Sewage Sludge, Nurtaç Öğleni̇, Sai̇m Özdemi̇r
Turkish Journal of Agriculture and Forestry
The responses of sludge faecal coliforms, Salmonella, and Ascaris lumbricoides to heat drying, solar dehydration, and inactivation in soil are examined in this study. The presence of Salmonella in raw sludge cake after treatment was low, and absent for most of the cases. Likewise, the viable Ascaris eggs were not determined because of absent or low prevalence. Faecal coliforms, on the other hand, drastically decreased from 4.2 × 10^7 MPN g^{-1} Dry Solid (DS) to absence by heat drying. Faecal coliform numbers in solar and non-solar drying treatments were not declined below 1.0 × 10^3 MPN g^{-1} after drying to …
Determination Of Microbial Contamination Sources At A Frankfurter Sausage Processing Line, Ebru Güngör, Nalan Gökoğlu
Determination Of Microbial Contamination Sources At A Frankfurter Sausage Processing Line, Ebru Güngör, Nalan Gökoğlu
Turkish Journal of Veterinary & Animal Sciences
This study was conducted to determine microbial contamination sources during sausage processing. The samples were taken at 6 different stages of the sausage processing line in a local plant. Minced meat, sausage batter, stuffed sausage, cooked sausage, peeled sausage, and pasteurized sausage samples were examined microbiologically. Moreover, spices and ice water used in production, personnel hands, and equipment were examined. Counts of total aerobic mesophilic bacteria, Staphylococcus aureus, Escherichia coli, yeasts, and molds in minced meat were found to be 7.02, 3.83, 4.42, and 1.62 log cfu/g, respectively. E. coli and yeast-mold counts in sausage batter reached 3.99 and 1.72 …
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
A Novel Ep Approach For Multi-Area Economic Dispatch With Multiple Fuel Options, P. S. Manoharan, P. S. Kannan, V. Ramanathan
A Novel Ep Approach For Multi-Area Economic Dispatch With Multiple Fuel Options, P. S. Manoharan, P. S. Kannan, V. Ramanathan
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a novel approach to multi-area economic dispatch problems with multiple fuel options using a hybrid evolutionary programming method. The objective is to minimize the operation cost of the entire system while satisfying the tie line constraints. In this paper, EP-LMO (Evolutionary Programming with Levenberg-Marquardt Optimization) technique is proposed to solve multi-area economic dispatch problems with multiple fuel options. The EP-LMO is developed in such a way that a simple evolutionary programming (EP) is applied as a base level search to find the direction of the optimal global region. And Levenberg-Marquardt Optimization (LMO) method is used as a …
Modeling And Calculation Of Electromagnetic Field In The Surroundings Of A Large Power Transformer, Leonardo Strac, Franjo Kelemen, Damir Zarko
Modeling And Calculation Of Electromagnetic Field In The Surroundings Of A Large Power Transformer, Leonardo Strac, Franjo Kelemen, Damir Zarko
Turkish Journal of Electrical Engineering and Computer Sciences
The presented study compares measured and calculated electromagnetic field quantities in the surroundings of a large power transformer with the aim to avoid the necessity of measuring the field on subsequent units and use a computer model instead. The influences of various objects located in the vicinity of the transformer during measurement are also analyzed and are taken into account in a computer model.