Pekmez: A Traditional Concentrated Fruit Product

Pekmez is a traditional Turkish food made by using different fruits such as grape, mulberry, fig, apple, and sugar beet. There are two different kinds of pekmez, either liquid pekmez or solid pekmez, produced in Turkey. The stages for processing liquid pekmez for all fruits, except mulberry, include washing, sorting, crushing, pressing, and boiling. By using liquid pekmez, and solidifying and bleaching its agents solid pekmez is produced. Pekmez is a healthful food due to its nutritional content and is used as a main source of energy based on its chemical composition. The carbohydrates in pekmez are generally in the form of natural sugars like glucose and fructose, which is nutritionally important for babies, children, sportsmen, and active workers. Pekmez production and its chemical composition should be adapted to the modern food technology and food safety requirements; at the same time, this adaptation should conserve the authentic properties of the product.     

Fourier transform infrared photoacoustic studies of the adsorption behavior of poly(2‐hydroxypropyl methacrylate) at solid–liquid interface

Adsorption of poly(2‐hydroxypropyl methacrylate) on alumina from dimethylformamide was studied by ultraviolet (UV) and Fourier transform infrared (FT‐IR) photoacoustic spectroscopy (FTIR PA) techniques. Adsorbent amount and concentration effects were investigated. The adsorption results are in conformity with Langmuir's isotherm. The differences observed in Langmuir parameters were explained by polymer–polymer, polymer–solvent, polymer–adsorbent, and solvent–adsorbent interactions. The fraction of carbonyl groups attached to the surface of alumina was calculated with a curve‐fitting computer program. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2750–2756, 2002     

Two-stage optimisation method for material flow and allocation management in cross-docking networks

Cross-docking is a relatively new logistics strategy in which items are moved from suppliers to customers through cross-docking centres without putting them into long-term storage. An important decision during the planning of cross-docking operations is related to the material flow management in the network, which has great potential to reduce transportation costs. However, until now, there has been a lack of studies regarding operations for both transportation of trucks between locations and trans-shipment of items in cross-docking centres. This study presents a novel two-stage mixed integer linear mathematical model for the transportation problem of cross-docking network design integrated with truck–door assignments to minimise total transportation costs from suppliers to customers. This model also considers incoming/outgoing truck-loading plans and product allocations in the cross-docking area with regard to the two-dimensional physical constraints. Due to the complexity of the problem, a genetic algorithm (GA) is proposed to solve large-sized problems. Computational studies are conducted to examine the validity of the two-stage model and performance of the GA. The computational studies show that the introduced model provides a comprehensive plan for material flow management in cross-docking networks and proposed GA is capable of obtaining effective results for the problem within a short computational time.     

A new metal chelate sorbent for glucose oxidase: Cu(II)- and Co(II)-chelated poly(N-vinylimidazole) gels

Poly(N-vinylimidazole) (PVIm) gels were prepared by irradiating a binary mixture of N-vinylimidazole (VIm)–water in a ⁶⁰Co-γ source having 4.5 kGy/h dose rate. In the glucose oxidase (GOx) adsorption studies, affinity gels with a swelling ratio of 1100% for PVIm and 40 and 55% for Cu(II)- and Co(II)-chelated PVIm gels, respectively, at pH 6.5 in phosphate buffer were used. FTIR spectra were taken for PVIm and Cu(II)- and Co(II)-chelated PVIm, and glucose oxidase adsorption on these gels, to characterize the nature of the interactions in each species. The results show that PVIm–glucose oxidase interaction is mainly electrostatic and metal ion–chelated PVIm gel–glucose oxidase interaction is of coordinate covalent nature. Cu(II) and Co(II) ions were chelated within the gels via amine groups on the imidazole ring of the gel. Different amounts of Cu(II) and Co(II) ions [maximum 3.64 mmol/g dry gel for Cu(II) and 1.72 mmol/g dry gel for Co(II)] were loaded on the gels by changing the initial concentration of Cu(II) and Co(II) ions at pH 7.0. GOx adsorption on these gels from aqueous solutions containing different amounts of GOx at different pH was investigated in batch reactors. GOx adsorption capacity was further increased when Cu(II) and Co(II) ions were attached [up to 0.53 g GOx/g dry Co(II)-chelated PVIm gels]. More than 90% of the adsorbed GOx was desorbed in 5 h in desorption medium containing 1.0M KSCN at pH 7.0 for plain gel and 0.05M EDTA at pH 4.9 for metal-chelated gel. Nonspecific glucose oxidase adsorption on/in the metal ion–chelated PVIm gel was investigated using 0.02M of phosphate buffer solution. The nonspecific GOx adsorption was determined to be about 18% for PVIm and 8% for the metal ion–chelated PVIm gels. The ionic strength effect was investigated both on PVIm and on the metal ion–chelated PVIm gels for the glucose oxidase adsorption. It was found that ionic strength was more effective on the PVIm gel because of the electrostatic interaction between protonated gel and the deprotonated glucose oxidase side chain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 446–453, 2001     

Flame resistant properties of LDPE/PLA blends containing halogen-free flame retardant

In this study, mixing petroleum-based low-density polyethylene (LDPE) with biodegradable poly(lactic acid) (PLA) is used as polymer matrix. Boron compounds, metal hydroxides, melamine (MLM), ammonium polyphosphate (APP), and pentaerythritol (PER) were used as reinforcement materials to improve flame resistance of polymer matrix. The composite materials were characterized by Fourier transform infrared spectroscopy, limiting oxygen index (LOI), thermogravimetric analysis, mechanical test, and scanning electron microscopy analyses. The LOI analysis showed that for samples, which included MLM, APP, and PER, the LOI values were dramatically improved. Especially, the LOI value of sample Q (LDPE80/PLA20/APP30/PER15/MLM15/ZB3) was enhanced about 95.17% compared to polymer mixing. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48960.     

Geochemical characteristics of the Eymir（Sorgun-Yozgat） manganese deposit,Turkey

The Eymir(Yozgat-Sorgun,Turkey) manganese deposit occurs within radiolarite cherts of the lower Cretaceous ophiolite complex.The mineralization was observed banded and lenticular forms.The geochemical characteristics of the Eymir deposit was studied by means of major oxide,trace and rare earth element(REE) contents and the origin of mineralization was discussed.The correlation coefficients indicated the presence of strong positive relations between major oxides and various trace elements(Al2O3-Fe2O3:r=0.75;Al2O3-CaO:r=0.79;Al2O3-TiO2:r=0.80;Al2O3-Zr:r=0.66;TiO2-Fe2O3:r=0.98;TiO2-CaO:r=0.82;TiO2-Zr:r=0.85 and Fe2O3-Zr:r=0.89) and the contribution of mafic terrigenous material to the deposition.In chondrite normalized REE graphics samples were characterized by highly negative and positive Ce anomalies.Europium showed negative anomaly in all samples.The negative Ce anomaly was typical to submarine hydrothermal deposits and positive Ce anomaly was indicative of hydrogenous deposits.The negative Eu anomaly showed contamination from the continental crust and/or sediment contribution via dehydration.Ce values in the Eymir mineralization were computed from the equation of Ceanom=lg [3xCeN/(2xLaN+NdN)] and anomalies were found as Ceanom<-0.1 in 8 samples and Ceanom>-0.1 in 12 samples.These values are indicative of both oxic and anoxic sedimentation conditions.The available data indicated that the Eymir manganese deposit is a hydrothermal-hydrogenous type volcanosedimentary mineralization.