Chemistry Commons^™

Corrosion And Wear Behaviour Of Highly Porous Ti-Tib-Tin$_{\Mathbf{X}}$ In Situ Composites In Simulated Physiological Solution, Fati̇h Toptan

Turkish Journal of Chemistry

Highly porous Ti matrix composites can be a solution for some of the major clinical concerns for the load bearing implants such as low tribocorrosion resistance, stress shielding, and lack of biological anchorage. In order to respond to these needs, highly porous Ti-TiB-TiN$_{x}$ in-situ composites were synthesized by pressureless sintering using BN as reactant and urea as space holder. Corrosion behaviour was investigated at body temperature, in phosphate buffer saline solution (PBS), by measuring open circuit potential (OCP) and cyclic polarization. Wear behaviour was studied in PBS by reciprocating against a 10 mm diameter alumina ball under 3 N of …

Comparative Modelling Of A Novel Enzyme: Mus Musculus Leucine Decarboxylase, Ari̇f Sercan Şahutoğlu

Turkish Journal of Chemistry

Leucine decarboxylase (LDC) is a recently proposed enzyme with no official enzyme commission number yet. It is encoded by the Mus musculus gene Gm853 which is expressed at kidneys, generating isopentylamine, an alkylmonoamine that has not been described to be formed by any metazoan enzyme yet. Although the relevance of LDC in mammalian physiology has not been fully determined, isopentylamine is a potential modulator which may have effects on insulin secretion and healthy gut microbiota formation. The LDC is a stable enzyme that specifically decarboxylates L-leucine but does not decarboxylate ornithine or lysine as its paralogues ornithine decarboxylase (ODC; EC: …

Isothermal Compressibility And Isobaric Thermal Shrinkage Of A Porous $\Alpha$-Alumina Compact: Thermodynamic Calculations, Yüksel Sarikaya, Müşerref Önal, Abdullah Devri̇m Pekdemi̇r

Turkish Journal of Chemistry

Two methods were proposed to calculate the thermodynamic parameters of porous ceramic compacts depending on their molar volume change with applied pressure and heating temperature, respectively. Molar volume of the porous $\alpha $-alumina ($\alpha $-Al$_{2}$O$_{3})$ compact was evaluated according to literature depending on both the applied pressure at room temperature and the heating temperature at atmospheric pressure. The isothermal compressibility coefficient, Gibbs energy, and work done on the compact by compression were calculated. The thermal shrinkage coefficient and activation energy as well as the change in enthalpy, entropy and Gibbs energy were calculated for partial sintering. The spontaneous nature of …

One-Step Synthesis Of Hierarchical [B]-Zsm-5 Using Cetyltrimethylammonium Bromide As Mesoporogen, Büşra Karakaya Yalçin, Bahar İpek

Turkish Journal of Chemistry

One-step facile synthesis of boron containing ZSM-5 microspheres is developed using 1,6-diaminohexane as the structure-directing agent and cetyltrimethylammonium bromide as the mesoporogen. High boron incorporation up to Si/B ratio of 38 is achieved and evidenced by the stretching vibrations of B-O-Si at 667 cm$^{-1}$ and 917 cm$^{-1}$ using Fourier-transform infrared spectra. The morphology of the crystals resembles berry-like spheres with sizes approximately 15 μm, which is composed of aggregated nanocrystals having sizes around 450 nm, is observed using scanning electron microscopy. The textural properties, i.e. the surface areas and pore volumes are investigated using N$_{2}$ adsorption at -196 $^{\circ}$C. t-plot …

A Review: A Comparison Of Different Adsorbents For Removal Of Cr (Vi), Cd (Ii) And Ni (Ii), Anja Pfeifer, Mojca Skerget

Turkish Journal of Chemistry

A review of the studies dealing with the removal of chromium, cadmium, and nickel ions with different adsorbents published in the literature between 2014 and 2018 is given in tabular form, along with the adsorption conditions, adsorption isotherm, and kinetic models applied by the authors to model the experimental data and adsorption capacities. The review focuses on the efficiency of ion removal.

Evaluation Of A Novel Nanocrystalline Hydroxyapatite Powder And A Solid Hydroxyapatite/Chitosan-Gelatin Bioceramic For Scaffold Preparation Used As A Bone Substitute Material, Sharmin Rahman, Kazi Hanium Maria, Mohammad Saif Ishtiaque, Arijun Nahar, Harinarayan Das, Sheikh Manjura Hoque

Turkish Journal of Chemistry

Artificially fabricated hydroxyapatite (HAP) shows excellent biocompatibility with various kinds of cells and tissues which makes it an ideal candidate for a bone substitute material. In this study, hydroxyapatite nanoparticles have been prepared by using the wet chemical precipitation method using calcium nitrate tetra-hydrate [Ca(NO$_{3})_{2}$.4H$_{2}$O] and di-ammonium hydrogen phosphate [(NH$_{4})_{2}$HPO$_{4}$] as precursors. The composite scaffolds have been prepared by a freeze-drying method with hydroxyapatite, chitosan, and gelatin which form a 3D network of interconnected pores. Glutaraldehyde solution has been used in the scaffolds to crosslink the amino groups ($\vert $NH$_{2})$ of gelatin with the aldehyde groups ($\vert $CHO) of chitosan. …

The Use Of Water-Soluble Phthalocyanines As Textile Dyes In Nylon/Elastane Fabric: Fastness And Antibacterial Effectiveness, Armağan Günsel, Ayşe Usluoğlu, Ahmet Turgut Bi̇lgi̇çli̇, Büşra Tosun, Gülnur Arabaci, Meryem Ni̇lüfer Yaraşir

Turkish Journal of Chemistry

This work reports on dyeing of nylon/elastane fabric with water-soluble phthalocyanines (1-4) bearing quinoline 5-sulfonic acid substituents on the peripheral or nonperipheral positions and determining the antibacterial efficiency of the phthalocyanine compounds and the dyed nylon/elastane fabrics. The light, washing, water, perspiration, and rubbing fastness properties of nylon/elastane fabrics dyed with phthalocyanines were also determined. The results showed that all dyed fabrics showed very good wet fastness values. The lightfastness value of the nylon/elastane fabric dyed with phthalocyanine dye (1) showed a much better value than the others. Also, the antibacterial efficiencies of the dyed nylon fabrics and the dye …

An Anthracene Based Fluorescent Probe For The Selective And Sensitive Detection Of Chromium (Iii) Ions In An Aqueous Medium And Its Practical Application, Erman Karakuş

Turkish Journal of Chemistry

An anthracene based fluorescent probe, integrated with thiophene moiety, exhibited selective and sensitive detection of chromium (III) ions over other metal ions. Its synthesis was achieved by simple mixing of two commercially available compounds, 2-aminoanthracene, and 2-thiophenecarboxaldehyde, in onestep without the needed complex purification process. The probe molecule (ANT-Th) offered exceptional features such as "turn-on" fluorescence response, low detection limit (0.4 μM), and fast response time (< 1 min) via C$=$N bond hydrolysis. Also, a simple test paper system was developed for the rapid detection of chromium (III) ions with the naked eye.

Oxidation Of Crotyl Alcohol By N-Chloro-4-Methylbenzene Sulphonamide In Acidic Medium And In Alkaline Media In The Presence Of Os(Viii) Catalyst-A Kinetic Pathway, Priyamvada Sharma, Riya Sailani, Anita Meena, Chandra Lata Khandelwal

Turkish Journal of Chemistry

The kinetic pathway of oxidation of crotyl alcohol by sodium salt of $N$-chloro-4-methylbenzene sulphonamide (chloramine-T) in acidic and alkaline medium has been studied. The speciation of chloramine-T has been made to suggest a proper and reasonable reaction mechanism. The thermodynamic quantities such as activation energy and activation entropy are evaluated in acidic as well as in catalysed alkaline medium. An anticipated reaction mechanism has been suggested.

Sorption Studies Of Europium On Cerium Phosphate Using Box-Behnken Design, Süleyman İnan

Turkish Journal of Chemistry

Amorphous cerium phosphate was prepared and characterized. Three-level Box-Behnken design (BBD) was employed to analyze the effect of process variables such as initial pH (2-6), contact time (60--180 min), and sorbent amount (0.05-0.15 g) on the sorption capacity of europium. Analysis of variance (ANOVA) revealed that the main effect of initial pH and sorbent amount has a substantial impact on the sorption of Eu(III). Probability F-value (F = 3 $\times $ 10$^{-3})$ and correlation coefficient (R$^{2}$ = 0.97) point out that the model is in good accordance with experimental data. The maximum sorption capacity of Eu(III) was found to be …

Modeling And Optimization Of Simultaneous Degradation Of Rhodamine B And Acid Red 14 Binary Solution By Homogeneous Fenton Reaction: A Chemometrics Approach, Nasrin Aliasgharlou, Morteza Bahram, Pezhman Zolfaghari, Naiemeh Mohseni

Turkish Journal of Chemistry

This study aimed to propose a mathematical method to investigate and optimize the simultaneous elimination process of multiple organic pollutants using the Fenton process. Hence, the treatment of rhodamine B (RB) and acid red 14 (AR14) dyes in their binary solution was studied. Multivariate curve resolution alternating least square (MCR-ALS), a novel chemometric method, was applied along with correlation constraints to resolute the UV-Vis spectrophotometric data, enabling quantification of investigated dyes despite a high spectral overlapping. Response surface methodology was adopted to assess the model and optimize individual and interactive effects of three independent factors (Fe$^{2+}$, H$_{2}$O$_{2}$ and initial pH) …

Effect Of Cnt Incorporation On Pan/Ppy Nanofibers Synthesized By Electrospinning Method, Ati̇ke İnce Yardimci, Meti̇n Tanoğlu, Selahatti̇n Yilmaz, Yusuf Selamet

Turkish Journal of Chemistry

In this study, carbon nanotubes (CNTs) added polyacrylonitrile/polypyrrole (PAN/PPy) electrospun nanofibers were produced. Average diameters of the nanofibers were measured as 268 and 153 nm for 10 and 25 wt% of PPy contents, respectively. A relatively higher strain to failure values (23.3%) were observed for the low PPy content. When as-grown CNTs (1 and 4 wt%) were added into the PAN/PPy blends, disordered nanofibers were observed to form within the microstructure. To improve the interfacial properties of CNTs/PAN/PPy composites, CNTs were functionalized with H$_{2}$SO$_{4}$/HNO$_{3}$/HCl solution. The functionalized CNTs were well dispersed within the nanofibers and aligned along the direction of …

Effects Of Composition On Catalytic Activities Of Molybdenum Doped Platinum Nanoparticles, Aslihan Sümer

Turkish Journal of Chemistry

The physical and chemical properties of bimetallic nanoparticles can be optimized by tuning the particle composition. In this study, we identified CO adsorption and dissociation energetics on five Pt-Mo nanoparticles at different concentrations, the lowest energy Pt$_{7}$, Pt$_{6}$Mo, Pt$_{5}$Mo$_{2}$, Pt$_{4}$Mo$_{3}$, and Mo$_{7}$ clusters. We have shown that the CO adsorption and dissociation energies and preferred CO adsorption sites are largely dependent on the composition of the nanoparticles. As the Mo concentration increases, the strength of the C-O internal bond in the adsorption complex decreases, as indicated by a decrease in the C-O stretching frequency. Also, more Mo sites in the …

Photochromic And Fluorescence Properties Of Coumarin Fulgimides, Khamis Nassor Ally, Leyla Öztürk, Mahmut Köse

Turkish Journal of Chemistry

Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation.

Synthesis And Bioactivities Of 1-(4-Hydroxyphenyl)-2-((Heteroaryl)Thio)Ethanones As Carbonic Anhydrase I, Ii And Acetylcholinesterase Inhibitors, Cem Yamali, Hali̇se İnci̇ Gül, Yeli̇z Demi̇r, Cavi̇t Kazaz, İlhami̇ Gülçi̇n

Turkish Journal of Chemistry

The discovery of enzyme targeting inhibitors is a popular area of drug research. Biological activities of the compounds bearing phenol and heteroaryl groups make them popular groups in drug design targeting important enzymes such as acetylcholinesterase (AChE, E.C.3.1.1.7) and carbonic anhydrases (CAs, EC 4.2.1.1). 1-(4-hydroxyphenyl)-2-((aryl)thio)ethanones as possible AChE and CAs inhibitors were synthesized, and their chemical structures were confirmed by IR, $^{1}$H NMR, $^{13}$C NMR, and HRMS. The compounds 2 and 4 were found potent AChE inhibitors with the Ki values of 22.13 ± 1.96 nM and 23.71 ± 2.95 nM, respectively, while the compounds 2 (Ki $=$ 8.61 ± …

In Silico Adme Predictions And In Vitro Antibacterial Evaluation Of 2-Hydroxy Benzothiazole-Based 1,3,4-Oxadiazole Derivatives, Afnan Ahmed Alghamdi, Mohammad Mahboob Alam, Syed Nazreen

Turkish Journal of Chemistry

In the present work, a library of fifteen 2-hydroxy benzothiazole-linked 1,3,4 -oxadiazole derivatives have been synthesized and confirmed using different analytical techniques. All of the synthesized compounds have been tested for antibacterial and in silico pharmacokinetic studies for the first time. From the ADME predictions, compound 4 showed the highest in silico absorption percentage (86.77%), while most of the compounds showed more than 70% absorption. All of the compounds comply with the Lipinski rule of 5, suggesting that the compounds possess good drug likeness properties upon administration. Furthermore, all of the compounds follow the Veber rule, indicating good bioavailability and …

Nanoparticles As Alternative Ceramic Glaze Colorants, Nathan Dinh

Honors Theses

Metallic nanoparticles, including gold and silver, have been used in wide-ranging applications due to their versatile characteristics. These include catalysis, biosensing, imaging, cancer treatments, and art. Due to the phenomenon called surface plasmon resonance, metallic particles change optical properties when sized in the nanoscale based on their composition, shape, diameters, or aspect ratios. In study, these robust nanoparticle systems are applied as an alternative to traditional bulk metal colorants in ceramic glazes.

In this study, the research goals are two-fold: to understand firing mechanism on the gold nanoparticle size and to develop these processes for wider use by regular artisans. …

One-Pot Silyl Ketene Imine Formation-Nucleophilic Addition Reactions Of Acetonitrile With Acetals And Nitrones, C. Wade Downey, Grace Ann L. Robertson, Jhonmattew Santa, Kari R. Flicker, William M. Stith

Chemistry Faculty Publications

Trimethylsilyl trifluoromethanesulfonate (TMSOTf) and a trialkylamine base promote the conversion of acetonitrile to its silyl ketene imine in situ when acetonitrile is employed as solvent. Residual TMSOTf acts as a Lewis acid catalyst to activate acetals and nitrones in the reaction mixture, yielding β-methoxynitriles and β-(silyloxy)aminonitriles, respectively. Some reaction products undergo elimination under the reaction conditions to provide the α,β-unsaturated nitrile directly.

Open Ensemble Modeling Of Confined Electrolytes, Serban Zamfir

Theses and Dissertations

The main purpose of my study was to work towards better understanding the behavior of salt solutions in nanoconfinements and its causes. To this end I have developed an in-house C++ code that can perform notoriously challenging open ensemble Monte Carlo molecular simulations, calculate relevant thermodynamic and extract structural information about each system. I use this code in my first project which deals with the intrusion/extrusion of aqueous NaCl into a nanopore open to a pressurized bulk environment. For my second project, I study the effect of explicitly accounting for intramolecular polarization and accompanying multi-body interactions on the uptake, structure, …

Selective Synthesis Of Trans-Fused Lactam-Lactones By Vicinal Difunctionalization Of Readily Affordable Allylic Lactams, Morgan J. Rodriguez

All Master's Theses

With intrinsic versatility and an overwhelming presence in natural products, nitrogen- and oxygen-containing heterocycles boast a plethora of medicinal properties. Specifically, lactams and lactones are the respective luminaries of the antibiotic and flavor worlds. However, the synthesis of fused lactams-lactones, especially those bearing trans-fusion, is challenging from the standpoints of chemoselectivity, stereoselectivity, and regioselectivity. In this thesis, the highly-selective, cost-effective, and high-yielding conversion of readily affordable allylic lactams into trans-fused lactam-lactones by intramolecular vicinal difunctionalization is explored. The approach is highly divergent and requires only two steps, which bodes well for the construction of medicinally pertinent fragments. It …

Synthesis, Optical, And Structural Properties Of Bisphenol-Bridgedaromatic Cyclic Phosphazenes, Bünyemi̇n Çoşut, Burcu Topaloğlu Aksoy, Süreyya Oğuz Tümay, Ahmet Şenocak, Serkan Yeşi̇lot

Turkish Journal of Chemistry

Phenoxy- and naphthoxy-substituted bisphenol-bridged cyclic phosphazenes were synthesized in 2 steps and their thermal, photophysical, and electrochemical properties were investigated. The structures of the cyclic phosphazene compounds were determined by ESI-MS mass spectrometry and $^{1}$H, $^{13}$C, and $^{31}$P NMR spectroscopies. The photophysical studies of phenoxy- and naphthoxy-substituted bridged cyclophosphazenes were investigated by means of absorption and fluorescence spectroscopies in different solvents. Thermal and electrochemical properties of the target compounds were also studied. Furthermore, the excimer emissions through intramolecular interactions in solution and in solid state were investigated by fluorescence spectroscopy and the theoretical calculations were performed in detail using DFT.

Chemosensor Properties Of 7-Hydroxycoumarin Substituted Cyclotriphosphazenes?, Gönül Yeni̇lmez Çi̇ftçi̇, Sergen Yilmaz, Nagi̇han Bayik, Eli̇f Şenkuytu, Esra Nur Kaya, Mahmut Durmuş, Mustafa Bulut

Turkish Journal of Chemistry

The newly synthesized cyclotriphosphazene cored coumarin chemosensors 5, 6, and 7 were successfully characterized by $^{1}$H NMR, $^{31}$P NMR, and MALDI-TOF mass spectrometry. Additionally, the photophysical and metal sensing properties of the targeted compounds were determined by fluorescence spectroscopy in the presence of various metals (Li$^{+}$, Na$^{+}$ , K$^{+}$ , Cs$^{+}$ , Mg2$^{+}$ , Ca2$^{+}$ , Ba2$^{+}$ , Cr3$^{+}$ , Mn2$^{+}$ , Fe3$^{+}$ , Co2$^{+}$ , Al3$^{+}$ , Hg$^{+}$ , Cu2$^{+}$ , Zn2$^{+}$ , Ag$^{+}$ , and Cd2$^{+}$) . The fluorescence titration results showed that compounds 5, 6, and 7 could be employed as fluorescent chemosensors for Fe3$^{+}$ ions with …

Entrapment Of Organic Fluorophores In Calcium Phosphate Nanoparticles Withslow Release, Laila Sadallah, Aicha Boukhriss, Hassan Hannache, Said Gmouh

Turkish Journal of Chemistry

Two organic fluorophores, fluorescein (F) and rhodamine B (Rd), were entrapped in calcium phosphate nanoparticles. The as-obtained nanoparticles can be used for biological release applications. For this aim, calcium phosphate nanoparticles were synthesized using the precipitation method. Structural analysis of these nanoparticles was performed using XRD, FTIR, and Raman spectroscopy, confirming that the synthesized nanoparticles were hydroxyapatite. TEM and SEM analyses demonstrated that these nanoparticles had a size of 20 nm and a well-defined morphology. F and Rd (about 0.5 wt.%) were entrapped in these nanoparticles and their release, as a function of time, was studied via UV-Vis spectroscopy. The …

Effect Of Surfactant Types On Particle Size And Morphology Of Flame-Retardantzinc Borate Powder, Yeli̇z İpek

Turkish Journal of Chemistry

Zinc borate is a boron-containing chemical material that is used to increase the flame retardancy of polymeric materials, dyes, cables, fabrics, carpets, and the internal parts of automobiles and planes. Commercially used zinc borate, which has the formula of 2ZnO· 3B$_{2}$ O$_{3}$· 7H$_{2}$ O, has a particle size between 10 and 20 μm. However, recent studies have shown that nanosized flame retardants have more superior flame retardancy and less negative effects on mechanical properties than microsized flame retardants. Nanosized flame retardants disperse more homogeneously and even low quantities are sufficient to provide high flame resistance. In this study, nano zinc …

Synthesis, Spectroscopic Studies, And Antioxidant Activities Of Novelthio/Carbohydrazones And Bis-Isatin Derivatives From Terephthalaldehyde, Hali̇t Muğlu, Hasan Yakan, Temel Kan Bakir

Turkish Journal of Chemistry

New bis(isatins-thio/carbohydrazones) based on Schiff bases were prepared from terephthalaldehyde biscarbohydrazone and 5-substituted isatins in the presence of a drop of sulfuric acid under reflux in ethanol. Terephthalaldehyde bis(thio/carbohydrazone) was synthesized by the reaction of (thio)/carbohydrazide and terephthalaldehyde in the presence of a few drops of acetic acid under reflux in ethanol. The structures of these synthesized compounds were determined using IR, $^{1}$H NMR, and $^{13}$C NMR spectroscopy and elemental analysis. The in vitro antioxidant activity of all the compounds was determined by the 1,1-diphenyl-2-picryl hydrazyl (DPPH.) free radical scavenging method. Compound 2 showed the best antioxidant activity.

A Comparative Study Of Silver Electrodeposition From Pyrophosphate-Cyanide And High Concentration Cyanide Electrolytes In The Presence Of Brighteners, Hati̇ce Kübra Akben, Servet İbrahi̇m Ti̇mur

Turkish Journal of Chemistry

A study of the electrodeposition of silver from 2 different types of electrolytes; (1) neutral pyrophosphatecyanide electrolyte and (2) alkaline high concentrated cyanide electrolyte in the presence of a variety of additives such as 2-mercaptobenzothiazole, potassium selenocyanate, and potassium antimony tartrate was performed. Influence of additives and cyanide concentration on microstructure and kinetics of the cathodic processes were studied. A brightener couple, 2-mercaptobenzothiazole and potassium antimony tartrate, were combined within this investigation anddetectedtobehighlyeffectiveforsilverelectrodeposition. Therapidincreaseincurrentdensityatthesamepotential interval related to grain refinement effect of potassium antimony tartrate was shown. The cyclic organic compound, 2mercaptobenzothiazole, polarizes the reduction to high cathodic potential in pyrophosphate …

Preparation And Characterization Of Form-Stable Phase Change Material/End-Of-Life Tires Composites For Thermal Energy Storag, Yeli̇z Konuklu

Turkish Journal of Chemistry

The management of end-of-life tires (ELT) waste gains importance in aspect of possible environmental and economic issues so the waste recycling becomes unavoidable. This study describes the fabrication and characterization of a new phase changing material (PCM)/ELT microcomposites that could be used in thermal energy storage. Paraffin together with the 4 fatty acids and ELT rubber powder are used as PCMs and as the supporting material, respectively. Paraffin/ELT composites are fabricated, as well, by the vacuum impregnation method in order to investigate the effect of the preparation method. The thermal, morphological, and chemical properties of the prepared PCM/ELT rubber microcomposites …

Fabrication And Biocompatibility Assessment Of Polypyrrole/Cobalt(Ii) Metal-Organic Frameworks Nanocomposite, Mehrnaz Mehrabani, Zeinab Ansari Asl, Farzaneh Rostamzadeh, Saeideh Jafarinejad Farsangi, Mahnaz Sadat Hashemi, Mozhgan Sheikholeslami, Zeinab Neisi

Turkish Journal of Chemistry

Nowadays, metal-organic frameworks (MOFs) have emerged as promising tools for different biological applications and therefore, efforts are ongoing to develop more biocompatible MOFs-based nanocomposites. We aimed to fabricate some new conductive nanocomposites of polypyrrole and cobalt-MOF with different weight percentages (PPy/x%Co-MOF)usingthesolutionmixingmethodandcharacterizethemthroughFT-IR(Fourier-transforminfrared), PXRD (powder X-ray diffraction), SEM (scanning electron microscope), and TEM (transmission electron microscope) techniques. The biocompatibility of nanocomposites was assessed by haemolytic, cytotoxic, and quantitative reverse transcription PCR (qRT-PCR) assays. FT-IR and PXRD results revealed that nanocomposites consisted of pure MOFs and PPy. Moreover, SEM results indicated their spherical morphology along with an average diameter of 190 nm. (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium …

Hosphorus-Nitrogen Compounds (Part 51): The Relationship Between Spectroscopic And Crystallographic Data Of Mono- And Di-Spirocyclophosphazene Derivatives With 4-Fluoro/Nitrophenylmethyl Pendant Arm/Arms, Aytuğ Okumuş, Gamze Elmas, Nuran Asmafi̇li̇z, Selen Bi̇lge Koçak, Zeynel Kiliç

Turkish Journal of Chemistry

A great wealth of structural information about phosphazenes can be gleaned from the combined spectroscopic and crystallographic data. When data from $^{31}$P NMR spectroscopy and X-ray crystallography are put together like pieces in a puzzle, a number of correlations can be obtained for phosphazene derivatives. A systematic study concerning the correlations among the structural parameters (e.g., $^{31}$P NMR data, endocyclic/exocyclic NPN bond angles and bond lengths) revealed some characteristics of mono- and di-spirocyclophosphazene derivatives bearing~4-fluoro/nitrophenylmethyl pendant arm/arms. These correlations include the relationship between the $\delta $P$_{spiro}$ shifts, the values of electron density transfer parameters $\Delta $(P--N), and the endocyclic and …

Allylphenoxypiperidinium Halides As Corrosion Inhibitors Of Carbon Steel And Biocides, Gunay Mehdiyeva Muzakir, Musa Bairamov Rza, Shahnaz Hosseinzadeh Bahador, Gulnara Hasanova Musa

Turkish Journal of Chemistry

A series of 1-(4-(2-allylphenoxy)butyl)piperidin-1-ium halides (4a-d) was synthesized and characterized via spectroscopic methods (FTIR, $^{1}$H NMR). The corrosion inhibition of the synthesized halides on carbon steel in water-salt-hydrocarbon environment, saturated with H$_{2}$S, was investigated. For this purpose, a series of techniques such as gravimetric measurement, potentiodynamic polarisation, and scanning electron microscope (SEM) were used and some thermodynamic parameters of corrosion process ($\Delta G_{ads.}$, $\Delta H^{0}_{ads.}$, $\Delta S^{0}_{ads.})$ were evaluated. The steel surface was checked by SEM, and the steel surface showed good surface coverage. The results showed that the synthesized compounds at the concentrations 125, 150 mg x L$^{-1}$ have …