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The main purpose of this study was to research the influence of different drying methods on the physical and qualitative properties of dried shrimps. Shrimps were dried with conventional methods at 60, 70 and 80?C between 330 to 210 min and 190 to 110 min, in an oven and vacuum oven respectively. Drying time was shortened with the use of a vacuum pump. The drying kinetics of the shrimp were studied, and effective moisture diffusion and activation energy were calculated for both methods. The Alibas model and the Midilli and Kucuk model provided the best experimental data with a high coefficient of determination (R2) for the oven and vacuum oven techniques, respectively. The final dried products were characterized by investigating the color characteristics, heavy metal content and by carrying out protein analyses. The rehydration ratio was also determined for the dehydrated shrimps. Drying conditions affected the color features so that shrimps dried in ovens and vacuum ovens showed an increase in brightness and yellowness values and a decrease in redness values. The concentration of As, Pb, Cd, Hg, Cu, Zn and Fe in the dried shrimp were within acceptable limits. The protein content of dried shrimp (?85%) is higher than that of undried shrimp (?20%).

In this study, characteristic drying behaviour and kinetics of blue mussels, which were dried with the traditional methods of cabinet-type, oven and vacuum oven drying, are studied. In a cabinet-type dryer there is air flow while in an oven dryer there is no air flow. In each method, Deff and Ea are calculated and colour analyses are done. According to the results, mussels are dried between 270-120 min, 570-300 min and 390-210 min, for the cabinet-type dryer, oven and vacuum oven, respectively. In each method, the Midilli and Kucuk model best fits experimental data with high coefficient of determination (R2) between 0.9995-0.9984, 0.9996-0.9993, and 0.9997-0.9993 for cabinettype, oven and vacuum oven dryer, respectively. Deff values were calculated between 1.89-4.94?10-9 m2/s, 0.89-1.63?10-9 m2/s and 1.17-2.28?10-9 m2/s for cabinet-type dryer, oven and vacuum oven methods, respectively. Also, Ea values were found to be 46.90, 29.57 and 32.85 kJ/mol, for cabinet-type dryer, oven and vacuum oven methods, respectively. The colour change was slightly affected by the change in the temperature.

The aim of this study was to produce a low-cost adsorbent to remove zinc from wastewater using orange, pineapple and pomegranate peels that had been carbonized by microwave and chemical activated using ZnCl2 and H2SO4. Effects of the fruit type, microwave processing time, activating agent type and adsorption contact time on the optimum adsorption efficiency were investigated. Characterization of the dried peels was done using thermogravimetry/differential thermal analysis, Fourier transform infrared spectroscopy and scanning electron microscopy devices. The dried orange, pineapple and pomegranate peels were subjected to 800 W microwave power for 1 to 4 min. The products obtained were characterized by FT-IR and SEM analyses. The zinc extraction efficiency of the produced activated carbons was determined using a UV spectrophotometer. When ZnCl2 was used, maximum zinc adsorption capacity of the orange peel was 37.08 mg/g for 2 h, pomegranate peel was 35.66 mg/g and pineapple peel was 37.23 mg/g for 4 h. When H2SO4 was used, maximum zinc adsorption capacity of pomegranate peel was 37.17 mg/g for 2 h and orange peel was 37.64 mg/g, pineapple peels were 36.99 mg/g for 4 h at 20 °C when the initial concentration of zinc was 40 mg/L and the constant biosorbent dosage was 0.25 g/L. The best result for the 3 fruit peels was obtained from activated carbons, which were microwaved at 800 W for 4 min. As a result, it was observed that environmentally friendly and cost-effective activated carbon could be successfully produced for use in zinc adsorption from wastewater.

Recently, sonochemistry has been used for the synthesis of inorganic compounds, such as zinc borates. In this study using zinc sulphate heptahydrate (ZnSO4·7H2O) and boric acid (H3BO3) as starting materials, a zinc borate compound in the form of Zn3B6O12·3.5H2O was synthesized using an ultrasonic probe. Product’s characterization was carried out with using X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and Raman spectroscopy. Zinc borate compound’s chemical bond structure was observed with Raman and FTIR. From the XRD results it was seen that Zn3B6O12·3.5H2O can be quickly synthesized upon heating at 80°C and 85°C (55 min) or 90°C (45 min) in very high yield (>90%). The minimum particle size obtained was ~143 μm from the SEM results. Zinc borate compound was synthesized at a lower temperature in less time than other synthesized zinc metal compound in literature.

Pectin, found in the cell walls of fruits and vegetables, is a complex colloidal polysaccharide. In this study, pectin was extracted using ultrasound and microwave-assisted extraction methods from waste lemon, mandarin, and kiwi peel to investigate their use as alternative source of pectin. Hydrochloric acid (HCl) and nitric acid (HNO(3)) were used as the extracting agents. The effects of microwave power (360–600 W) and irradiation time (1, 2, 3 min) for microwave-assisted extraction (MAE) and of temperature (60 and 75 °C) and sonication time (15, 30, 45 min) on ultrasound-assisted extraction (UAE) on the yield of extracted pectin from the peels were investigated. Optimum conditions were determined for the extraction of pectin from all of the peel samples with the two extraction methods. The produced pectin yield and the degree of esterification were determined and, FT-IR and SEM analyses were performed. Kiwi peel gave the highest yield of extracted pectin using HCl as the solvent with 17.30% yield via UAE at 75 °C for 45 min and 17.97% yield via MAE at 360 W for, 3 min. It was concluded that lemon, mandarin, and kiwi peels all contained pectin and that MAE gave a better yield than UAE and could thus be used as an efficient and rapid technique for the extraction of pectin from the peels. The chemical structures of the pectin obtained using the two different extraction methods were similar and showed a high degree of methoxylation.

Bu çalışmada, iki farklı kalsiyum kaynağıkullanılarak üretilen hidroksiapatit katkısı eklenerek yüksek mukavemetliakrilik kemik yapıştırıcısı üretilmiştir. Üretilen örnekler, XRD ve FT-IRkullanılarak karakterize edilmiştir. Termal davranışlar ve yüzey morfolojileriDTA/TG ve SEM teknikleri kullanılarak belirlenmiştir. Ca(OH)2 vedeniz kabuğundan üretilen hidroksiapatit ilavesi, ortaya çıkan yapıştırıcılarınbasınç dayanımını (74 MPa'dan 106 MPa ve 103 MPa'ya) arttırmıştır. Bu yenikemik yapıştırıcıları, ticari olarak temin edilebilen örneklerlekarşılaştırılabilecek mekanik dayanımlara sahiptir ve hidroksiapatitin kemikyapısında mevcut doğal bir mineral olduğu için daha biyolojik olarak uyumluolduğuna inanılmaktadır., In thisstudy, production of acrylic bone cement which has high strength by addinghydroxyapatite additive that was produced using two different calcium sourceswas aimed. Characterizations were performed using XRD, and FT-IR. Thermalbehaviors and surface morphologies were determined using DTA/TG and SEMtechniques. The addition of hydroxyapatite produced from Ca(OH)2 andseashell increased the compressive strength (from 74 MPa to 106 MPa and 103MPa) of the resultant cements respectively. These new bone cements havemechanical strengths comparable with commercially available cements and arebelieved to be more biocompatible since hydroxyapatite is a natural mineralpresent in the bone structure.

Streszczenie Celem tego artykułu jest synteza boranu cynku przy użyciu węglanu cynku, kwasu borowego, referencyjnego boranu cynku (ZB) jako substancji aktywnej oraz badanie efektywności tego procesu modyfikowanego odczynnikami i parametrami reakcji na hydrofobowość i wydajność syntezy boranu cynku. Dotyczy to działania różnych czynników modyfikujących hydrofobowość i parametry reakcji: glikol propylenowy (PG) (0−6%, kerozyna 1−6%, kwas oleinowy (OA) 1−6% oraz rozpuszczalniki: alkohol izopropylowy (IPA), etanol i metanol. Po pierwsze, badano jak wpływają następujące parametry reakcji na uzysk boranu cynku: czas reakcji (1−5 h), wskaźnik reaktywacji (H3BO3 : ZnO), (2−5), udział zarodków krystalizacji (0−1,5%) w odniesieniu do kwasu borowego, temperatura reakcji (50−120°C), temperatura chłodzenia (10−80 °C), szybkość mieszania (400−700 obr./min). Ponadto, reakcje były przeprowadzone w określonych warunkach mieszania mechanicznego i magnetycznego. Wytwarzany boran cynku ze względu na hydrofobowość badano metodami: dyfrakcji rentgenowskiej XRD, spektroskopii FT-IR oraz pomiarami kąta zwilżania. Reasumując, stwierdzono, że boran cynku można otrzymać z powodzeniem z różnymi rozpuszczalnikami wpływającymi na jego hydrofobowość.

Zinc borate hydrate (Zn3B6O12·3.5H2O) was synthesized from zinc sulfate heptahydrate (ZnSO4·7H2O), anhydrous zinc chloride (ZnCl2), and boric acid (H3BO3). The product was characterized by X-ray diffraction, Fourier-transform infrared and Raman spectroscopy, and thermal gravimetry and differential thermal gravimetry. The effects of reaction time and temperature on product morphology were studied by use of scanning electron microscopy. Results from thermal analysis showed that dehydration occurred in two steps. Thermal dehydration kinetics were investigated by use of the Coats–Redfern and Horowitz–Metzger non-isothermal kinetic methods. In the Coats–Redfern method, activation energies were found to be 225.40 and 570.63 kJ/mol for the first and second steps, respectively. In the Horowitz–Metzger method, activation energies were found to be 254.33 kJ/mol for the first step and 518.22 kJ/mol for the second step.

Zinc borate (ZB) was synthesized using zinc oxide, boric acid synthesized from colemanite, and reference ZB as seed. The effects of reaction parameters such as reaction time, reactant ratio, and seed ratio on its yield were examined. Then, the effects of palm oil with solvents (isopropyl alcohol (IPA), ethanol, and methanol) added to the reaction on its hydrophobicity were explored. Reactions were carried out under determined reaction conditions with magnetically and mechanically stirred systems. The produced ZB was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and measurements of contact angle identified hydrophobicity. The results showed that hydrophobic ZB was successfully produced under determined reaction conditions. The change of process parameters influenced its yield and the usage of palm oil provided hydrophobicity.

Boron minerals, considered future essential materials, can be used as raw materials in the production of boron carbide. In this study, boron carbide, the hardest material after diamond and cubic boron nitride, is characterized and the neutron shielding behavior is investigated. The characterization and structural evaluation of the boron carbide sample was performed using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FT-IR) and Raman Spectroscopy. In addition, a neutron Howitzer was used to measure the neutron permeability of boron carbide samples of various thicknesses. The sample composed of 12.5 g of boron carbide powder and 3 g of Wax® had the lowest neutron permeability rate (62.1%). Pellet 3 had the smallest total macroscopic cross section of boron carbide particles, 0.722 ± 0.0071 cm−1.

The aim of this study was to synthesize zinc borate using zinc oxide, reference boric acid, and reference zinc borate (reference ZB) as the seed, and to investigate the effects of modifying agents and reaction parameters on the hydrophobicity and yield, respectively. The reaction parameters include reaction time (1–5 h), reactant ratio (H3BO3/ZnO by mass: 2–5), seed ratio (seed crystal/(H3BO3+ZnO) by mass: 0–2wt%), reaction temperature (50–120°C), cooling temperature (10–80°C), and stirring rate (400–700 r/min); the modifying agents involve propylene glycol (PG, 0–6wt%), kerosene (1wt%–6wt%), and oleic acid (OA, 1wt%–6wt%) with solvents (isopropyl alcohol (IPA), ethanol, and methanol). The results of reaction yield obtained from either magnetically or mechanically stirred systems were compared. Zinc borate produced was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and contact angle tests to identify the hydrophobicity. In conclusion, zinc borate is synthesized successfully under the optimized reaction conditions, and the different modifying agents with various solvents affect the hydrophobicity of zinc borate.

This study investigated the use of solid waste fly ash in the production of lightweight concrete. Fly ash is an industrial waste obtained from the coal-fired thermal generating power plant and it is used in the production of additive construction materials. In Turkey more than 15 million tonnes of fly ash is produced each year, but only a small amount is utilised. The industrial waste fly ashes used in this study came from the power plant at Iskenderun Sugozu, Cayirhan, Tuncbilek and Seyitomer. Lightweight aggregate manufactured from the fly ash and Na-bentonite was used in a pelletisation process. The lightweight concrete manufactured from fly ash aggregate was analysed in terms of the slump and density of fresh concrete and the density, compressive strength and tensile splitting strength of hardened concrete. In the present study, the effects of fly ash aggregates from different power plant when used for lightweight concrete production purposes were investigated and the results obtained were quite satisfactory for the related design requirements.

In Turkey, pyrite ash is created as waste from the roasting of pyrite ores in the production of sulfuric acid. These processes generate great amounts of pyrite ash waste that creates serious environmental pollution due to the release of acids and toxic substances. Pyrite ash waste can be used in the iron production industry as a raw material because of its high Fe2O3 concentration. The aim of this study was to investigate the reduction behaviour of pyrite ash pellets. The pyrite ashes were reduced to obtain the iron contained in pellets. Pyrite ashes samples were pelletized dried at 105 °C for 24 h and sintered at 1200 °C for 30 min. then reduced in a pressure of 4 atm. under argon gas. The mineralogical transformations that occurred during reduction were analysed by X-ray diffraction and X-ray fluorescence. The X-ray diffraction and X-ray fluorescence measurements of these samples showed that Fe3O 4 was successfully reduced to a metallic iron phase in a laboratory-scale electric arc furnace.

In this study, Zn

In this study, physical and chemical characteristic of the treatment sludge obtained byBergama- Ovac1k treatment plant and the possibility to evaluate them in glass industry wereinvestigated, In this treatment plant, 277,882 tons of sludge is annually produced. Thechemical composition of the waste sludge's is determined by gravimetric method and it isexamined by X-Ray diffraction (XRD), X-Ray fluorescence (XRF) and Fourier TransformInfrared Spectrophotometer (FT-IR) equipments. The chemical composition of the treatmentsludge showed that it is potential to be used in a glass industry to produce Borosilicate glassand Flat glass with the addition of chemical substances. In order to examine the compositionof the samples, their analyses were made by (FT-IR) and (XRF) equipments

In Turkey, pyrite, copper melting gases and sulfur are used as a raw material in sulfuric acid production. Pyrite ashes are obtained as a result of the sulfuric acid production process during the roasting of pyrite ores. These wastes are generally landfilled or dumped into the sea. Pyrite ash wastes can be utilized as a raw material in the production of iron ore, and thus environmental pollution can be avoided; however, these wastes need to achieve certain physical and chemical properties before they are used. Pyrite ashes are agglomerated into pellets to allow them acquire the required properties for use as iron ore in a blast furnace. The essential parameters affecting the pelletization of pyrite ashes are studied using bentonite as a binder. The metallurgical properties of pyrite ash, bentonite, a mixture of pyrite ash and bentonite, and sintered pellets are studied using X-ray analyses. Wet-drop, wet-crush, dry-crush and sintered-crush tests are carried out to investigate the strength of the pyrite ash wastes pellets prepared from feeds with different sieve size and bentonite content. The results of this analysis demonstrate that pyrite ashes can be agglomerated into pellets and used as feed for the blast furnace in the iron production industry.

Pyrite ash is created as waste from the roasting of pyrite ores during the production of sulphuric acid. These processes generate great amounts of pyrite ash waste that is generally land filled. This creates serious environmental pollution due to the release of acids and toxic substances. Pyrite ash waste can be utilized in the iron production industry as a blast furnace feed to process this waste and prevent environmental pollution. The essential parameters affecting the pelletization process of pyrite ash were studied using bentonite as a binder. Experiments were then carried out using bentonite and a mixture of bentonite with calcium hydroxide and calcium chloride in order to make the bentonite more effective. The metallurgical properties of pyrite ash, bentonite, calcium hydroxide, calcium chloride, a mixture of these and sintered pellets were studied using X-ray analysis. The crushing strength tests were carried out to investigate the strength of pyrite ash waste pellets. The results of these analyses showed that pyrite ash can be agglomerated to pellets and used in the iron production industry as a blast furnace feed. The crushing strength of the pellets containing calcium hydroxide and calcium chloride in addition to bentonite was better than the strength of pellets prepared using only bentonite binder.

Magnesium borate (MB) is a technical ceramic exhibiting high heat resistance, corrosion resistance, great mechanical strength, great insulation properties, lightweightness, high strength, and a high coefficient of elasticity. Zinc borate (ZB) can be used as a multifunctional synergistic additive in addition to flame retardant additives in polymers. In this study, the raw materials of zinc oxide (ZnO), magnesium oxide (MgO), and boric acid (H3BO3) were used in the mole ratio of 1 : 1 : 9, which was obtained from preexperiments. Using the starting materials, hydrothermal synthesis was applied, and characterisation of the products was performed using X-Ray diffraction (XRD) and Fourier transform infrared (FT-IR) and Raman spectroscopies. The forms of Zn3B6O12·3.5H2O, MgO(B2O3)3·7(H2O), and Mg2(B6O7(OH)6)2·9(H2O) were synthesised successfully. Moreover, the surface morphology was investigated using scanning electron microscopy (SEM), and the B2O3content was determined. In addition, the reaction yields were calculated. The results of the B2O3content analysis were in compliance with the literature values. Examination of the SEM images indicated that the obtained nanoscale minerals had a reaction efficiency ranging between 63–74% for MB and 87–98% for ZB. Finally, the fire-retarding properties of the synthesised pure MBs, pure ZBs, and mixtures of MB and ZB were determined using differential thermal analysis and thermal gravimetry (DTA-TG) and differential scanning calorimetry (DSC).

Fly ash is currently being generated at a rate of million tons every year and represents an important waste problem. Bentonite and molasses are used in a wide range of applications. The samples of Orhaneli fly ash were analyzed by X-ray fluorescence, Fourier transform infrared spectroscopy, and scanning electron microscope. Depending on the results of the analysis, morphology and chemical compositions of Orhaneli fly ash were investigated in detail. Orhaneli fly ash, bentonite (0 and 1 % in terms of fly ash, w/w), and molasses (0–0.75 mL) were pelletized under 30 MPa of pressure for zinc adsorption in wastewater. As a result, it was seen that the usage of Orhaneli fly ash was proper for zinc (Zn2+) adsorption and an optimum adsorption yield with 90 % was found at a compound with Orhaneli fly ash (10 g), bentonite (0 %), and molasses (0.25 mL) at 2.5 h of reaction time, pH 5, 20 °C of reaction temperature, and 300 rpm of stirring rate. Sorption isotherm and sorption kinetics for Zn2+ on fly ash (with bentonite and molasses) can be explained by Freundlich isotherm and pseudo-second-order kinetic models. Based on the experimental data, it was seen that Orhaneli fly ash and molasses waste could be evaluated for Zn2+ adsorption from wastewater, environmentally.

In general, zinc oxide and boric acid are used to produce zinc borate. In this study, zinc carbonate was used instead of zinc oxide as the novel zinc source. The purpose of this study was to synthesize hydrophobic, nanostructured zinc borate (3ZnO·3B2O3·3.5H2O) by reaction of zinc carbonate, instead of zinc oxide, with boric acid reference material, and with zinc borate reference material as seed. The modifying agents propylene glycol, kerosene, and oleic acid were used to produce hydrophobic zinc borate. Different solvents (isopropyl alcohol, ethanol, and methanol) were used to obtain a homogeneous phase. The effects of different modifying agents and solvents on the hydrophobicity and nanostructure of the product were investigated. The synthesized zinc borate was characterized by X-ray diffraction and Fourier-transform infrared spectroscopy. Contact angles were measured to determine the hydrophobicity of the products and scanning electron microscopy was used to study both the morphology and nanostructure of the products. Hydrophobic, nanostructured zinc borate was successfully produced by use of zinc carbonate instead of zinc oxide as the novel zinc source. Use of different modifying agents and solvents affected both hydrophobicity and nanostructure.