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https://hdl.handle.net/20.500.12885/1748

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A BODIPY decorated multiple mode reusable paper-based colorimetric and fluorometric pH sensor
(Elsevier, 2022) Ozturk, Dilek; Omeroglu, Ipek; Gol, Cem; Durmus, Mahmut
In this study, two difluoroboradiazaindacene (BODIPY) compounds bearing diethylaminostyryl groups were synthesized in order to establish colorimetric and fluorometric paper-based pH sensors. The structures of these novel BODIPY compounds were identified by NMR (H-1, C-13, B-11, and F-19), elemental analysis, MALDI-TOF, FT-IR, UV-vis and fluorescence spectroscopies as well as single-crystal X-Ray data. The DFT study was also per-formed to optimize of these two novel BODIPY structures. Electrochemical measurements were applied to estimate their redox potentials. Photophysical properties such as fluorescence quantum yield and lifetimes were investigated to determine the effect of acid addition in both DMSO and 1,4-dioxane solutions of the studied BODIPY derivatives. Also, pKa values of the synthesized compounds (1a and 1b) were determined from absorbance and fluorescence measurements by acid titration studies. The paper-based pH sensor behavior of these BODIPY derivatives was investigated and their performances were determined on the lemon juice samples as a real sample analysis. A simple, cost-effective, rapid, portable, colorimetric, and fluorometric paper-based BODIPY sensing platform was developed in this study for the detection of the variety of pH changes in lemon juice.
Symmetrical and Asymmetrical Thiophene-Coumarin-Based Organic Semiconductors
(American Chemical Society, 2023) Altınışık, Sinem; Özdemir, Mücahit; Kortun, Arzu; Zorlu, Yunus; Yalçın, Bahattin; Köksoy, Baybars; Koyuncu, Sermet
Organic semiconductors are a valuable material class for optoelectronic applications due to their electronic and optical properties. Four new symmetric and asymmetric thiophene-coumarin derivatives were designed and synthesized via Pd-catalyzed Suzuki and Stille Cross-Coupling reactions. Single crystals of all synthesized thiophene-coumarin derivatives were obtained, and π···π interactions were observed among them. The π···π interactions were supported by UV-vis, transmission electron microscopy, and atomic force microscopy analyses. The photophysical and electrochemical properties of the coumarins were investigated and supported by density functional theory studies. Fluorescence quantum yields were recorded between 36 and 66%. Moreover, mega Stokes shifts (175 nm or 8920 cm) were observed in these new chromophore dyes. The emission and absorption colors of the thiophene-coumarin compounds differed between their solution and film forms. Electrochemically, the highest occupied molecular orbital levels of the coumarins increased with the 3,4-ethylenedioxythiophene group, leading to a narrowing of the band gap, while the phenyl bridge weakened the donor-acceptor interaction, expanding the band gap.
Synthesis and photovoltaic properties of novel ferrocene-substituted metallophthalocyanines
(Royal Society of Chemistry, 2021) Özdemir, Mücahit; Köksoy, Baybars; Kuruca, Halid; Altindal, Ahmet; Durmus, Mahmut; Koyuncu, Sermet; Yalcin, Bahattin; Bulut, Mustafa
In this paper, a series of new metallophthalocyanines, including ferrocene groups, were designed, synthesized and, characterized, and their photovoltaic properties were investigated as alternative electron-donor materials in bulk heterojunction (BHJ) solar cells. These products were synthesized by a Sonogashira cross-coupling reaction between tetraiodophthalocyanine and ethynyl ferrocene. The newly synthesized phthalocyanines (4-6) were characterized by FT-IR, UV-Vis, H-1 NMR, and MALDI-TOF spectroscopic methods and elemental analysis. The electrochemical characterizations were carried out by cyclic voltammetry as well as differential pulse voltammetry. Density functional theory calculations were realized to prove the charge separation between ferrocene as an electron-donor and the phthalocyanine ring as an acceptor. According to UV-Vis measurements, a 25 nm red-shift was observed for complex 4 compared with complexes 5 and 6. Finally, the photovoltaic performance of these compounds used as an electron-donor moiety in a BHJ device were investigated. A function of different blend ratios was tested by fabricating a series of BHJ devices with the architecture of FTO/PEDOT:PSS/4-6: PCBM blend/Ag with an identical thickness of the active layer. The results indicated that the photovoltaic conversion efficiency of BHJ devices exhibited a strong blend-ratio dependence. The maximum power conversion efficiency was obtained by 5-based devices, as 3.65%, with a blend ratio of 1.5 : 1.0 under standard AM 1.5 illumination.
Thermodynamic studies on tert-amine modified polystyrene based polymer/solvent systems by inverse gas chromatography method
(Yıldız Teknik Üniversitesi, 2021) Adıgüzel, Ayşegül Çiğdem
In the present work, vinyl benzyl chloride (VBC) was polymerized by using free radical polymerization. The obtained PVBC was reacted with dibutyl amine to obtain tertiary amine modified polystyrene based polymer (PVBC-Dibutyl amine). The inverse gas chromatography (IGC) method was used to examine the thermodynamic properties of the polymer. Firstly, the retention diagrams of some polar and non-polar solvents on PVBC-Dibutyl amine were obtained over a temperature range from 135 to 160 degrees C. Then, the thermodynamic parameters, including Flory-Huggins interaction parameter, weight fraction activity coefficient, partial molar heat of sorption, and partial molar heat of mixing were determined via interactions between the polymer and selected solvents at infinite dilution. The results reveal that the alkanes are poor solvents for the polymer whereas n-butyl acetate, i-butyl acetate, ethyl acetate, n-propylbenzene, i-propylbenzene, and ethylbenzene are moderately solvents in the studied temperature range.
Algorithmically Guided Optical Nanosensor Selector (AGONS): Guiding Data Acquisition, Processing, and Discrimination for Biological Sampling
(American Chemical Society, 2021) Smith, Christopher W.; Hızır, Mustafa Salih; Nandu, Nidhi; Yigit, Mehmet, V
Here, we report a biomarker-free detection of various biological targets through a programmed machine learning algorithm and an automated computational selection process termed algorithmically guided optical nanosensor selector (AGONS). The optical data processed/used by algorithms are obtained through a nanosensor array selected from a library of nanosensors through AGONS. The nanosensors are assembled using two-dimensional nanoparticles (2D-nps) and fluorescently labeled single-stranded DNAs (F-ssDNAs) with random sequences. Both 2D-np and F-ssDNA components are cost-efficient and easy to synthesize, allowing for scaled-up data collection essential for machine learning modeling. The nanosensor library was subjected to various target groups, including proteins, breast cancer cells, and lethal-7 (let-7) miRNA mimics. We have demonstrated that AGONS could select the most essential nanosensors while achieving 100% predictive accuracy in all cases. With this approach, we demonstrate that machine learning can guide the design of nanosensor arrays with greater predictive accuracy while minimizing manpower, material cost, computational resources, instrumentation usage, and time. The biomarker-free detection attribute makes this approach readily available for biological targets without any detectable biomarker. We believe that AGONS can guide optical nanosensor array setups, opening broader opportunities through a biomarker-free detection approach for most challenging biological targets.
Semi-Purified Saponins of Holothuria poli Associated Antiproliferation in Tumor Cell Lines
(Routledge, 2022) Mert-Ozupek, Nazli; Basbinar, Yasemin; Uysal-Kilic, Tugba; Koz, Ömer; Ellidokuz, Hulya; Cavas, Levent
The incidence of cancer has exhibited an increasing trend in recent years because of many reasons such as environmental and nutritional factors. There is a great need for the development of new and natural molecules with lower side effects in the therapy of cancer. It was aimed to evaluate the antiproliferative effect of semi-purified triterpene glycosides of Holothuria poli on different human cancer cell lines. The body walls of H. poli as the main sources of saponins were used and the saponin content of the extract was characterized by MALDI-TOF/MS. The antiproliferation activity of the characterized extract was tested on cancer cell lines. The extract showed antiproliferative effect on the studied cancer cell lines. The mass analysis results reveal that Holothurin A is one of the saponins within the extract. The measured IC50 values were found as 31.41 ± 2.20, 77.45 ± 0.23, and 34.79 ± 0.90 µg mL−1 for HT-29, UPCI-SCC-131, and T84 cell lines, respectively. H. poli secretes not only specific saponins but also a cocktail of them. Specific versus. cocktails of the saponins and by also applying organic modification must be studied in further research to understand their mechanisms in the antiproliferation studies since this paper reveals promising results.
Qualitative study on the effects of hydroxyl functionalized multiwall carbon nanotube and silica doped-epoxy composites
(John Wiley and Sons Inc, 2022) Yaşaroğlu, İnci; Aras, Ömür; Kaya, Yunus
Epoxy resins have great potential for industrial applications because of their excellent properties such as good adhesion, durability, higher strength, and so forth. But, their high-viscosity limits industrial usage. Reducing the viscosity with suitable diluents provides an advantage on industrial scale processing, but this also causes a decrease in their chemical and mechanical properties. The production of epoxy-based composite materials provides good mechanical, heat, and solvent resistance properties. Therefore, determination of additives amount and dilution ratio for specific working area are important for these materials. In this context, this study first includes synthesis of bisphenol A-based epoxy resin and characterization with fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. Second, chemical, mechanical, thermal, and surface properties of the resin were investigated by varying the reactive/nonreactive diluents and additives. Multiwall carbon nanotube (MWCNT-modified with triton X-405 nonionic surfactant) and fumed silica as additives were used in this study. Mechanical and chemical tests were applied to 49 types of materials. In order to see the significance levels and synergistic effects of diluents on tensile strength, 3D graphs were obtained with the experimental and modeled data. ANOVA was also performed for significance levels of the diluents. After that, the effects of silica and carbon nanotube additive on tensile strength were investigated. As a result of the tensile test and TGA analysis of the pure epoxy, the ultimate tensile strength was measured as 59.07 MPa, Tg (°C), and Tm (°C) values were found as 175.5 and 304.0°C. These results increased for the nanocomposite material prepared with 2% fumed silica and 0.1% MWCNT (modified YAM) as 81.64 MPa, 192.2 and 333.3°C. It was also shown that the ultimate tensile strength, which decreased with dilution of pure epoxy, could be increased significantly with the additives
In-situ preparation of halloysite nanotube-epoxy thermoset nanocomposites via light-induced cationic polymerization
(Elsevier Ltd, 2021) Bekin Acar, Seda; Çiftci, Mustafa; Bouharras, Fatima Ezzahra; Raihane, Mustapha; Tasdelen, Mehmet Atilla
In the present study, homogeneous mixtures of halloysite nanotubes (HNTs)-epoxy nanocomposites are prepared through chemical treatments. Naturally present halloysite nanotubes (HNT) are primarily modified by 3-(glycidyloxypropyl)trimethoxysilane and subsequently utilized as nanofillers in a mixture of bisphenol A diglycidyl ether and trimethylolpropane triglycidyl ether by varying weight % of modified HNT from 0 to 8%. Photoinitiated cationic crosslinking polymerization of this mixture facilitates the in-situ preparation of HNT/thermoset nanocomposites at room temperature. The covalent attachment of HNT in the thermoset matrix has been confirmed by monitoring the characteristic signals of the mixture, nanofiller, neat thermoset, and final nanocomposite using fourier transformed infrared (FT-IR) spectroscopy. Furthermore, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses proved the existence and distribution of HNT in the thermoset nanocomposites. Indeed, a combination of agglomerated/non-agglomerated HNTs in the thermoset matrix is also determined. On the other hand, mechanical properties of nanocomposites are significantly improved with increase in HNT loading up to 4% ratio. Adding 4% of modified HNT into epoxy increased its tensile strength and elasticity modulus by 6.9 times and 2.3 times than the corresponding neat epoxy thermoset, respectively, without scarifying thermal stability. Therefore, the HNT/epoxy thermoset nanocomposites are suitable candidates for various applications as an alternative of expensive carbon nanotube containing analogues.
Influence of POSS nanoparticles on the microstructure and mechanical properties of carbon fiber reinforced epoxy hybrid composites
(John Wiley and Sons Inc, 2021) Kurtulus C.; Kuyumcu M.; Çiftci, Mustafa; Tasdelen M.A.
The possibility to design composites with superior properties by incorporation of nanoscale reinforcing material still remains to be fulfilled. In the current study, bisphenol A diglycidyl ether-based epoxy resin has been successfully modified with polyhedral oligomeric silsesquioxane (POSS) nanoparticles to give epoxy/POSS nanocomposites. Carbon fiber reinforced composites with different fiber orientations are processed via vacuum bagging technique using this composite as the matrix. Scanning electron microscopy indicated that POSS nanofillers homogeneously distributed in the matrix. As proved by the tensile, flexural, and interlaminar shear strength tests, the inclusion of POSS nanofillers in the polymer matrix has promoted significant improvements in the mechanical properties of the carbon fiber reinforced POSS/epoxy hybrid composites compared to the analogues with neat epoxy matrix. Thus, hybrid composites with exceptional properties are obtained via a straightforward modification in the matrix and a novel paradigm without using any expensive compound has been added to the library of nanocomposite formulations.
Inhibition of steel corrosion by some schiff and mannich bases: A theoretical evaluation
(Ukrainian State University of Chemical Technology, 2021) Gece, Ender Gökhan
There is no doubt that the value and importance of using computational methods in corrosion science are becoming gradually recognized. Drilling deeper into the thought that certain molecular electronic descriptors such as ionization potential, electron affinity, HOMO-LUMO gap and dipole moment matter, because they present a unique solution to comprehend the inhibition properties of corrosion inhibitors, leads us to a further quandary. The reliability of such parameters is the subject of acrimonious debate, and thus, the present study is an extension of this attempt to contemplate earlier experimental results reported for some Schiff and Mannich bases as corrosion inhibitors for steel in neutral aqueous solutions by using density functional theory calculations. Due to the sources of uncertainties like the structure of the molecular model, the description of environmental efforts and errors related to the nature of quantum chemical methods, it was inferred that no coherent picture could be emerged about the corrosion inhibition properties of the studied compounds through calculated descriptors. © 2021 Ukrainian State University of Chemical Technology.
Electrochemical Evaluation of Sustainable Corrosion Inhibitors via Dynamic Electrochemical Impedance Spectroscopy
(American Chemical Society, 2021) Slepski P.; Gerengi H.; Gece, Ender Gökhan; Kaya E.; Rizvi M.; Szociński M.
Finding suitable measurement methods for the effective management of electrochemical problems is of paramount importance, particularly for improving efficiency in corrosion protection. The need for accurate measurement techniques specific to nonstationary conditions has long been recognized, and promising approaches have emerged. This chapter introduces dynamic electrochemical impedance spectroscopy as a novel advancement in electrochemistry that can be used efficiently in galvanostatic and potentiostatic modes. The review focuses first on an explanation of the method and second on presenting a comprehensive corpus covering available studies that have applied dynamic electrochemical impedance spectroscopy for the purpose of preventing corrosion phenomena.This chapter defines the merits of this novel approach compared with the conventional electrochemical impedance spectroscopy method.
Coumarin bearing asymmetrical zinc(II) phthalocyanine functionalized SWCNT hybrid nanomaterial: Synthesis, characterization and investigation of bifunctional electrocatalyst behavior for water splitting
(Elsevier B.V., 2021) Akyüz D.; Şenocak A.; Köksoy, Baybars
A novel asymmetrical zinc(II) phthalocyanine (Coum-Pc) bearing three 7-ethynyl-3-(3,4,5-trimethoxyphenyl) coumarin and one ethyloxy azido groups was synthesized and characterized for the first time. This novel asymmetric Coum-Pc was covalently attached to single walled carbon nanotube (SWCNT) containing terminal ethynyl groups via the azide-alkyne Huisgen cycloaddition (Click) reaction for preparation of coumarin bearing zinc(II) phthalocyanine functionalized SWCNT hybrid nanomaterial (SWCNT-Coum-Pc). Hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalyst for water splitting behavior of SWCNT-Coum-Pc hybrid nanomaterial were evaluated. The SWCNT-Coum-Pc hybrid reduced the onset potential required for HER by approximately 200 mV compared to SWCNT catalyst in acidic medium. The SWCNT-Coum-Pc catalyst reduced the HER overpotential of 570 mV at a current density of 10 mA cm−2 in alkaline medium. It also exhibited outstanding activity in OER, required only an overpotential of 330 mV at a current density of 10 mA cm−2. Heterogeneous rate constants of the electrodes from impedance analysis were used to calculate the value of charge transfer resistance and the conductivity of the composite film. The presence of Coum-Pc groups on the SWCNT surface increased for both the conductivity and electron transfer rate of the SWCNT. Therefore, SWCNT-Coum-Pc hybrid significantly improved the performance of OER and HER for water splitting. The present work provided a promising ground for the of SWCNT-Coum-Pc hybrid as a bifunctional electrocatalyst for water splitting.
Application of inverse gas chromatography in the surface characterization of diethanol amine modified polystyrene based polymer
(TUBITAK, 2021) Adıgüzel, Ayşegül Çiğdem
In the present work, diethanol amine modified polystyrene based polymer (PVBC-Diethanol amine) was synthesized and characterized, then surface properties of the polymer were examined by inverse gas chromatography method at infinite dilution. The retention diagrams obtained based on the interaction of polar and nonpolar probes with the polymer were drawn over a temperature range from 30 to 55°C. Through the diagrams, the dispersive component of the surface free energy, gSD of the polymer surface, and the specific enthalpy of adsorption, DHAS , of probes on the polymer were also calculated. Lewis acid, KA, and Lewis base, KD , parameters of PVBC-Diethanol amine surface were determined. The values of KA and KD indicated that PVBC-Diethanol amine surface exhibited a basic behavior.
A comprehensive statistical approach for determining the effect of two non-ionic surfactants on thermal conductivity and density of Al2O3–water-based nanofluids
(Elsevier B.V., 2021) Altun, Aycan; Şara, Osman Nuri; Şimşek B.
The purpose of this study was to evaluate the effect of surfactants on the density and thermal conductivity values of water, as well as to separately evaluate the variations in these values due to particle–surfactant interaction. To this end, Al2O3–water-based nanofluids with different particle volume concentrations (0.3–1.1%) were prepared, as were Tween 80 and Tergitol NP-10 surfactants at different weight ratios (0.2–0.8%). Density and thermal conductivity of obtained nanofluids were then measured at temperatures ranging from 298 to 338 K. Statistical evaluation was carried out to determine the effects of surfactant type, temperature, particle concentration, and surfactant concentration on density and thermal conductivity. Additionally, the sedimentation method, zeta potential, and particle size analysis were utilized to estimate the stability of nanofluids. Results showed that when base fluid (water and surfactant) density was determined, the use of surfactants had no additional impact on the density of the nanofluids. The highest observed improvement in thermal conductivity was 7.5%, obtained using 0.2 wt% Tween 80 and 1.1 vol% Al2O3 at 338 K. Although particle concentration was the most influential factor and surfactant type was not statistically significant for density ratio, the thermal conductivity ratio was affected by other factors in addition to particle concentration.
A density functional theory study of molecular H2S adsorption on (4,0) SWCNT doped with Ge, Ga and B
(Elsevier B.V., 2021) Geçim, Gözde; Özekmekçi, Mehtap
The molecular adsorption of hydrogen sulfide has been investigated theoretically by using Density Functional Theory for gallium (Ga), germanium (Ge) and boron (B) doped (4,0) single-walled carbon nanotubes (SWCNTs). The method of B3LYP was utilized with basis sets of 6-31G(d,p) and LANL2DZ. Adsorption energy and adsorption enthalpy, HOMO and LUMO energy values, HOMO-LUMO energy gap, chemical hardness, chemical potential, electronegativity and Gibbs free energy values have been evaluated in this study. All doped SWCNT structures have negative Gibbs free energy and adsorption energy values which make these clusters promising for the removal of H2S by adsorption. However, Ge doped SWCNT cluster has the lowest HOMO-LUMO energy gap and chemical potential, highest electronegativity with minimum adsorption energy values when compared to other clusters. Furthermore, it is softer than other metal doped SWCNT clusters due to the lower chemical hardness value.
A Mini Review on Unassailable Inhibiting Roles of Some Compounds in Neutral Media
(American Chemical Society, 2021) Gece, Ender Gökhan
This chapter deals with the use of some reported corrosion inhibitors in neutral media with a focus on a few prevailing metals (iron, aluminum, and copper) and highlights the evolving corrosion science needs for the advancements. As evidenced, our knowledge on inhibition mechanisms by such compounds in saline environments is still far from complete,and our ability to predict the future state of novel inhibitors is hindered due to several emerging global environmental issues. Nevertheless, electrochemical studies as well as some computational approaches provide rich opportunities to expand our understanding of the possible postulants of future corrosion inhibitors for neutral solutions.
Screening of simple carbohydrates as a renewable organocatalyst for the efficient construction of 1,3-benzoxazine scaffold
(Elsevier Ltd, 2021) Yıldırım A.; Kaya, Yunus; Göker M.
A convenient protocol for the two component preparation of 1,3-benzoxazines by using several protected and unprotected carbohydrate molecules as organocatalysts have been developed which is broadly applicable to condensation reaction between variety of Mannich bases and paraformaldehyde. This study revealed that fructose have much higher catalytic activity than the other carbohydrates and can be an alternative to metal-containing catalysts as a green renewable organocatalyst for efficient and rapid construction of 1,3-benzoxazine skeleton. In this context, 21 benzoxazine compounds were successfully synthesized and spectral characterizations of these compounds were carried out by spectroscopic methods and elemental analysis. Furthermore, density functional theory (DFT) calculations have been performed to study the detailed mechanism of organocatalyst assisted synthesis of the benzoxazine monomers. The results obtained from these calculations showed that the more realistic reaction pathway involves formation of a phenolate based intermediate which loses a water molecule to form benzenaminium ion. Subsequently, this ion provides the formation of the corresponding benzoxazines with good yields through the intramolecular ring closure step.
A newly synthesized ionic liquid as an effective corrosion inhibitor for carbon steel in HCl medium: A combined experimental and computational studies
(Elsevier Ltd, 2021) Öztürk, S.; Gerengi H.; Solomon M.M.; Gece, Ender Gökhan; Yıldırım A.; Yıldız M.
Surfactants present exciting adsorption chemistry due to their dual nature, i.e the present of the hydrophobic and hydrophilic parts in their structures. However, the inhibition performance of surfactants is influenced by their chemical structure as well as the nature of the electrolyte. In acidic media, high concentration of tri-cationic surfactants is required for effective surface protection. Herein, we report the synthesis of a novel tri-cationic surfactant containing three quaternized nitrogen atoms and its corrosion inhibitive effect for carbon steel in 1 M aqueous HCl medium. The molecular structure of the surfactant was elucidated by 1H NMR and 13C NMR spectroscopic techniques and its anti-corrosion activity was investigated by electrochemical impedance spectroscopy, potentiodynamic polarization and dynamic electrochemical impedance spectroscopy methods. The results obtained from the corrosion studies show that the synthesized surfactant is quite effective against the low carbon steel corrosion and at low inhibitor concentration. The inhibition efficiency obtained at 5 mg/L concentration is above 90%, showing that the anti-corrosion effect of the synthesized surfactant on the metal surface is strong even at low inhibitor concentration. Moreover, some physicochemical parameters namely, the critical micelle concentration, surface tension, micelle formation free energy, and emulsion stability have been calculated and used to explain the correlation with the corrosion inhibition mechanism. Additionally, to support the results from the electrochemical measurements, surface morphological examination using energy dispersive X-ray spectroscopy (EDAX) and scanning electron microscope (SEM) methods have been performed. The EDAX and SEM results prove the adsorption of the tri-cationic surfactant molecule on the metal surface. The adsorption followed the Langmuir adsorption isotherm and calculated Kads (equilibrium constant of the adsorption process) value reflects strong interaction. More so, density functional theory (DFT) results corroborate the experimental results. The synthesized tri-cationic surfactant is a potential candidate for the formulation of acid corrosion inhibitor for acid cleaning applications.
Efficient direct conversion of lignocellulosic biomass into biobased platform chemicals in ionic liquid-water medium
(Elsevier Ltd, 2021) Niş, Berna; Özsel Kaya, Burçak
In this study, the conversion of corn straw, sorghum and cellulose into valuable chemicals (furfural, 5-hydroxymethylfurfural, levulinic acid) in different ionic liquid-water medium were investigated. Different reaction parameters such as reaction temperature, time and solvent ratio were optimized to achieve the highest conversion of biomass and selectivity of the products. Under the optimal reaction conditions (180 °C, 30 min, 1:5 ratio), 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM]HSO4) was found to display the highest efficiency which can be attributed to the acidic character of the ionic liquid. 117.4 mg levulinic acid, 11.8 mg 5-hydroxymethylfurfural and 9.4 mg furfural were obtained per g of sorghum. The results showed that 5-fold higher quantity of LA was obtained from sorghum biomass in comparison with pure cellulose. In addition, Amberlyst-15 was examined as a solid acid catalyst for conversion of cellulose in [BMIM]HSO4-water solvent system resulting in 4.6-fold increase in the quantity of levulinic acid. This study provides an alternative single step approach for production of valuable chemicals from renewable biomass.
Synthesis, Structural Calculations and Molecular Docking Studies of a Novel Uracil Derived Organic Molecule
(2018) Koz, Gamze
Anovel uracil derived compound, (E)-5-((3-chloro-2-hydroxybenzylidene)amino) pyrimidine-2,4(1H,3H)- dione, was synthesized and characterized using spectroscopic techniques. The interaction of the molecule with DNA was explored using computational methods which revealed that the molecule could act as a groove binder. The physicochemical properties of the molecule such as frontier molecule orbitals and chemical reactivity parameters were also investigated.

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