Identification of Turkish extra virgin olive oils produced in different regions by using NMR (1H and 13C) and IRMS (13C/12C)

Isotope ratio mass spectroscopy (IRMS) and nuclear magnetic resonance (NMR) spectroscopy techniques are two of the analytical methods that are used to characterize food products. The aim of this study is to classify extra virgin olive oil (EVOO) samples collected from different regions of Turkey based on ¹H and ¹³C NMR spectra along with IRMS δ¹³C carbon isotope ratio data by using chemometrics multivariate data analysis methods. A total of 175 EVOO samples were analyzed in 2014/15 and 2015/16 harvest seasons. Multivariate classification and clustering models were used to identify geographical and botanical origins of the EVOOs. IRMS results showed that there was no significant difference in terms of δ¹³C values between the years in terms of harvest year (p > 0.05), only extraction phase and variety were statistically significant factors (p < 0.05). The interactions of the factors showed that the harvest year × variety interaction is important. The outcomes of this research clearly indicated that considering the partial least squares discriminant analysis result with NMR spectra, the percent success of the model in the South Marmara, North Aegean, and South Aegean region samples were 95%, 95.7%, and 96.4% in the model set, respectively. The results showed that by using classification and clustering models, geographic marking and labeling of these oils can be carried out regardless of differences in year and production systems (2 and 3 phase extraction system) according the NMR analysis.     

Preparation of a Novel Nano-scale Lead (II) Zig-Zag Metal–Organic Coordination Polymer with Ultrasonic Assistance: Synthesis,Crystal Structure,Thermal Properties,and NBO Analysis of [Pb(μ-2-pinh)N<Subscript>3</Subscript> H<Subscript>2</Subscript>O]<Subscript>n</Subscript>

A novel nano-cauliflower-shaped lead(II) metal–organic coordination polymer, [Pb(μ-2-pinh)N₃ H₂O]_n (1), was synthesized using an ultrasonic method. The nanostructure was characterized by scanning electron microscopy (SEM), X-ray powder diffraction, IR spectroscopy, elemental analysis, and thermal analysis. The compound was structurally characterized by single-crystal X-ray diffraction. The coordination compound takes the form of a zig-zag one-dimensional polymer in solid state. The coordination number of the lead(II) ions is six (PbN₄O₂) with three nitrogen atoms and one oxygen atom from two linker organic ligands, as well as one oxygen from coordinated water and one nitrogen atom from terminal coordinated azide anion. It has a stereo-chemically active lone electron pair, and the coordination sphere is hemidirected. The zig-zag 1D chains interact with neighbouring chains through weak interactions, creating a 3D supramolecular metal–organic framework. Lead oxide nanoparticles were obtained by thermolysis of the new nano coordination compound at 180 °C with oleic acid as a surfactant. The morphology and size were further studied using SEM. Natural bond orbital analyses demonstrate the electronic properties of the lead centre and other atoms.     

UMV control via FOSMO

Journal of Mechanical Science and Technology - In this work, the speed and direction angle of an unmanned vehicle (UMV) are controlled by using a sliding mode controller (SMC). However, no...     

Experimental evaluation of different spectral methods for damage estimation of an electrical panel bracket mounted on a military wheeled vehicle

Journal of Mechanical Science and Technology - This study evaluates different frequency domain vibration fatigue methods by verifying the results of the analyses with the experimental data on the...     

Influence of concrete properties on bleeding and evaporation

The bleeding of concrete and the evaporation of water from the surface of concrete, which affect plastic shrinkage cracking, were investigated. The quantities of water evaporated from concrete specimens exposed to different temperatures, relative humidities and windy conditions were evaluated. The evaporation of water from the surface of C25 and C35 concretes, which were made using PKC/B 32.5R and PC 42.5 cements, was determined. It was observed that the cement type affects the bleeding of concrete. Also concrete mixes containing high cement contents yielded minimum quantities of bleeding. It was observed that concrete mixes containing more mixing water yielded the maximum amount of water evaporation.     

One-Dimensional Cobalt(II) and Zinc(II) Succinato Coordination Polymers with Nicotinamide: Synthesis, Structural, Spectroscopic, Fluorescent and Thermal Properties

Cobalt(II) and zinc(II) succinato (suc) coordination polymers with nicotinamide (nia), {[Co(μ-suc)(H₂O)₂(nia)₂] · 2H₂O} _n (1) and {[Zn(μ-suc)(H₂O)₂(nia)₂] · 2H₂O} _n (2) have been synthesized and characterized by elemental analyses, magnetic moments, IR and TG-DTA. Single-crystal X-ray analyses of 1 and 2 reveal that these complexes are isostructural and crystallize in triclinic space group Complexes 1 and 2 are 1-D coordination polymers, in which the metal(II) ions exhibit an octahedral geometry with two suc, two nia and two aqua ligands. The nia ligand is N-bonded, while the suc ligand bridges the metal centers through the carboxylate groups. The 1D chains are further assembled to form 3D networks by strong N–H···O and OW–H···O hydrogen bonds. IR spectra confirm the coordination modes of both suc and nia ligands, while TG-DTA data are in agreement with the crystal structures. Fluorescent analysis in the solid state shows that all complexes display intraligand (π–π*) emissions of nia.     

Thermal conductivity of MgO-C refractory ceramics: Effects of pyrolytic liquid and pyrolytic carbon black obtained from waste tire

In the present study, thermal conductivity and mechanical properties of MgO-C refractory ceramic bricks were investigated. Pyrolytic liquid and pyrolytic carbon black obtained from pyrolysis of waste tires were used as a resin and carbon source, respectively. The pyrolysis of the tires was conducted in a fixed bed reactor at the temperature of 500?°C with a 15?°C/min heating rate under nitrogen flow (0.5?lt/min). Before using in MgO-C refractory ceramic blends, pyrolytic products were purified with the acidic extraction methods which resulted in 61and 66?wt%. decreases in sulfur and ash contents in pyrolytic carbon, respectively. After this treatment of pyrolytic liquid, the sulfur content was reduced by 24?wt%. Eight different blends of MgO-C refractory ceramics consisting of different pyrolytic product contents were prepared, pressed, and tempered at 250?°C, and then characterized in terms of porosity, thermal conductivity, and density. The mechanical behavior of the samples was tested using a three-point bending test. Archimedes test was employed to determine the porosity and density. Surface properties of the bricks were analyzed by scanning electron microscopy (SEM). The obtained results were compared with a reference consisting of graphite and resin. The results revealed that mechanical and thermal properties of the developed bricks were highly sensitive to the porosity and the carbon source as well as the type of binder.     

A three-dimensional silver(I) coordination polymer involving a new bridging mode of saccharinate

A three-dimensional silver(I)-saccharinato (sac) coordination polymer [Ag₂(μ-sac)₂]_n has been synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. The silver(I) ions are doubly bridged by the imino N and carbonyl O atoms of two sac ligands, leading to a dimer [Ag₂(μ-sac)₂] with a very short Ag–Ag contact of 2.8622(6) Å. The dimeric units are linked by unique Ag–C_sac (η¹) bonds into two-dimensional ladder-like layers, which are further assembled into a three-dimensional network by weak Ag?O(sulphonyl) and π(sac)?π(sac) interactions. Complex 1 is the first example of a polymeric network involving the η¹ Ag–C bonds. In addition to the new coordination mode of sac, the IR spectrum and thermal properties of the complex were discussed.     

Evaluation of fresh state,rheological properties,and compressive strength performance of cementitious system with grinding aids

Grinding aids (GA) affect the fresh and hardened state properties of cement systems in addition to the economic and ecological advantages they provide. Nevertheless, there is not enough information in the literature regarding the effect of GA utilization on the rheological properties of cementitious systems. In this study, the effect of different types of GA utilization on the grinding efficiency, setting time, and physical properties of cement and rheological properties of cement paste was investigated. Besides, adsorption of the water-reducing admixture (polycarboxylate ether [PCE]) to the cement containing GA was investigated by total organic carbon analysis. According to the results, regardless of the type of GA, while the grinding efficiency was positively affected by GA utilization in cement, the adsorption degree of PCE, some fresh and rheological properties of the mixtures were negatively affected. With the use of GA, an increase was observed in the early age compressive strength of mortar mixtures. Consequently, the properties of cementitious systems containing GA should be taken into consideration to assess GA performance in addition to the grinding efficiency.     

Friction and wear behaviors of reciprocatingly extruded Al–SiC composite

This study focuses on the friction and wear behaviors of reciprocatingly extruded Al–SiC composites. To increase the strength of metal matrix composites and refine the grains of the matrix some deformation processes can be applied, such as reciprocating extrusion (RE). For this reason, RE was carried out on a 6061 Al matrix by a SiC (20 μm) reinforced composite one. The billets were extruded under a pressure of 17.5 MPa at 573 K with a 10:1 extrusion ratio. The reciprocating extrusions were carried out by using up to 15 passes.