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Two new random donor-acceptor (D-A) copolymers, signed as P1 and P2, were designed and synthesized. Electrochemical and spectroelectrochemical measurements were performed to investigate absorption, energy levels, electronic and optical band gaps for comparison. The polymers were used as donor polymers in the active layer to fabricate non-fullerene, bulk heterojunction (BHJ) organic photovoltaics (OPVs). Investigations were carried out through the conventional BHJ structure; ITO/PEDOT: PSS/Active Layer/LiF/Al, where active layer consists of 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d']- s -indaceno[1,2-b:5,6-b']dithiophene (ITIC) as the acceptor and thienopyrroledione containing donors. The device based on P1:ITIC(1:1) blend with a thickness of 161 nm gave the best performance with a power conversion efficiency (PCE) of 7.94%, an open-circuit voltage (V OC) of 0.86 V, a short-current density (J SC) of 18.45 mA cm−2 and a fill factor (FF) of 50.12%. The highest PCE obtained from P2 based organic solar cell is 1.96%. P2 exhibited low solubility attributed to the lack of alkyl groups enhancing polymer solubility, electronic properties, and photovoltaic performances. The research outputs exhibit that introduction of alkyl chains on the polymer backbone can enhance device performance. [Display omitted] • Two new random copolymers based on thienopyrroledione (TPD) were synthesized. • Polymers were used as donor materials in non-fullerene BHJ OPVs. • Effect of introduction of alkyl chains on device performance was investigated. • The best result for power conversion efficiency was found to be 7.94%. • Alkyl chains' effect on OPVs' performance is investigated. [ABSTRACT FROM AUTHOR]

In the present study, instead of the burning the Elbistan lignite (L) having low calorific value and the biomasses (Balikesir Olive Bagasse “OB” and Adiyaman peat “P”), co-liquefaction process was conducted in order to produce valuable product as an oil. The effect of the biomasses ratio in the mixture on the properties of the co-liquefaction products and oil yield was also investigated in detail. The chemical characterization, composition and calorific value of the starting materials and the co-liquefaction products (char, asphaltene, preasphaltene and oil) were determined using XRD, FTIR, calorimeter, GC/MS and elemental analysis. In addition, the morphological and thermal behavior of the starting materials was also investigated by TG/DTA and SEM. The results showed that the biomasses accelerated thermolysis of the lignite due to their amount of volatile content, cellulose, hemicelluloses and lignin in the structure causing the high total conversation ratio. The highest oil yield was obtained as 39.5% for L:P:OB (1:2:3). Calorific values of the char, asphaltene, preasphaltene and oil were determined as 1235 kcal/kg, 9080 kcal/kg, 8650 kcal/kg and 5135.19 kcal/kg, respectively. The obtained oil was identified as a paraffinic-low waxy oil whose density is 0.94 g/cm 3 . [ABSTRACT FROM AUTHOR]

Abstract: It is known that the presence of excess fines in heap leaching operations may cause low recovery due to reduced heap permeability and/or channeling of lixiviant flow. These problems are mitigated to some extent by agglomeration pretreatment prior to heap leaching. Sulfuric acid leach solution is the conventional liquid bridge used for copper ore agglomeration, but these agglomerates exhibit poor stability when compared to the agglomerates formed using stucco binder, calcium sulfate hemihydrates, CaSO4·½H2O. Results obtained from agglomeration experiments on the Zaldivar ore reveal that the stucco hydration reaction provides the agglomerates with more stability, increased size with less release of fines, and better permeability of the packed agglomerate bed. A phase diagram has been constructed to identify preferred agglomeration conditions. Finally a proposed description for the action of stucco binder during the agglomeration process is presented and discussed. [Copyright &y& Elsevier]

Abstract: In this paper, the thermoluminescence (TL) dosimetric characteristics of Al-doped LiB3O5 compounds are presented. The powder samples were prepared by the solid-state reaction method and the formation of the compounds were confirmed by an X-ray diffraction study. The TL studies of undoped and Al-doped LiB3O5 samples showed similar glow curve structures. They have three TL glow peaks at about 60, 130 and 200°C after heating at a constant heating rate of 1°C/s. Their comparative TL studies indicated that 5wt% Al-doped LiB3O5 compound was approximately 240 times more sensitive than undoped compound. The TL emission spectra of Al-doped LiB3O5 showed a maximum band at around 520nm. The main dosimetric characteristics, which are namely the TL dose response, TL sensitivity, fading, minimum detectable dose, reproducibility, precision of dose measurement and annealing procedure, indicated that Al-doped LiB3O5 sample, can be used in dosimetric applications. The trap parameters namely order of kinetics (b), activation energy (E) and frequency factor (s) associated with the glow peaks in beta irradiated undoped and Al-doped LiB3O5 samples were obtained by glow curve deconvolution (GCD) program. [Copyright &y& Elsevier]

• Turkey is the second largest iron and steel producer in Europe. • In order to added value of the mill scale wastes, they were used in the mortars. • The novel mortars had an electromagnetic wave shielder properties. • This may be contributing the solve the scale storage problem of wastes. Electromagnetic (EM) wave shielder mortar can be produced by mixing cement, natural limestone, tap water with mill scale (mill scale-I and mill scale-II) which is one of the biggest disposal area problems of the iron-steel sector in Iskenderun, Hatay. In this paper, the detail analysis and information were presented on the influence of electromagnetic properties of mortars including iron steel industry waste mill scales to contribute the solving waste problems. The mortar samples were prepared using different volume of mill scales (5, 10, 15 and 30%) which were substituted with the natural fine aggregate. The mechanical properties (flexural and compressive strength) and the EM shielding properties (using the free space test method) of the mortars were compared with each other and also a control mortar samples. Our results indicated that the obtained mortars containing 15% mill scale had nearly same mechanical properties with the control mortar and they provided better solution for EM shielding. Especially, the mortar containing mill scale-II might be used to create novel construction material with shielding characteristics in entire wireless communication bands due to the cubic crystal structure and ferromagnetic properties of the mill scale-II. The mortar prepared using mill scale-I might be utilized to fabricate novel high strength radomes that behave as air in transmission respect. All experimental results point out that the waste mill scales are viable candidates for EM wave shielder for the buildings and will gain added value as well as solve the scale storage problem of the iron and steel industry. [ABSTRACT FROM AUTHOR]

Abstract: In mining operations, jaw and gyratory crushers are generally used for primary crushing, and cone crushers are used for secondary crushing. During the past decade, however, high-pressure grinding rolls (HPGR) are being considered due to potential processing benefits such as energy savings, improved exposure/liberation and particle weakening. At this time there is no detailed quantification of particle damage and downstream benefits from HPGR crushing are uncertain. In the present research, copper ores (copper oxide ore and copper sulfide ore) were crushed by a jaw crusher and by HPGR and the products were evaluated for particle damage and copper grain exposure by X-ray computed tomography. Column leaching was done to determine the rate and extent of copper recovery. X-ray computed tomography analysis and laboratory column leaching experiments for copper oxide ore revealed that products from HPGR crushing have more particle damage and higher copper recoveries when compared with products of the same size class from jaw crusher crushing. Generally the copper recovery from column leaching of the oxide ore was found to be dependent on the extent of grain exposure, which increases with a decrease in particle size. In the case of the copper sulfide ore, copper recovery was found to be independent of the crushing technique despite the fact that more particle damage was observed in products from HPGR crushing. This unexpected behavior for the copper sulfide ore might be due to the high head grade and strong leach solution. Column leaching results also show that about 80–90% of the copper was recovered from the copper sulfide ore in a relatively short leaching time irrespective of crushing technique. As expected, copper recoveries improved with a decrease in the particle size of the copper sulfide ore as exposure of copper mineral grains increased. [Copyright &y& Elsevier]

In this study, different types of waste aluminum produced in daily life and their pure equivalents were evaluated and compared in terms of their hydrogen generation performance through the water-splitting reaction. An experimental system was designed for the production process that consisted of electrodes, DC power supply, alkaline solution, and various waste aluminum products. The hydrogen generation rate of the aluminum source was then measured to determine the optimum conditions for hydrogen production with different types of pure and waste aluminum, normality of the aqueous solution, and applied DC voltage. The best results for micro-hydrogen generation were obtained using pure powder Aluminum, which was attributed to the increased active surface area for the reaction. For beverage can waste (and its powder form), the maximum hydrogen generation rate (cm3/g.min) was achieved using the powder form of the waste aluminum at 2 N alkaline solution. However, the total amount of hydrogen generation (cm3/g) yielded different results compared to the maximum hydrogen generation rate where, when the amount of hydrogen generation volume per mass was considered, the beverage can pieces achieved the best result under constant voltage. This result was attributed to a longer total reaction time. • Hydrogen production from waste Al drink cans are studied. • Parametric study is applied with voltage, concentration and forms of Al. • Micro-production of hydrogen is a good candidates for a sustainable energy system. [ABSTRACT FROM AUTHOR]

In the present study, undoped whitlockite and ZnO doped-Whitlockite, which is the second most abundant inorganic material in bone structure, were synthesized from sea urchin skeleton. The obtained bioceramic materials were characterized by XRD, FT-IR, and SEM and their antibacterial activities were determined using the inhibition zone diameters of Escherichia coli and Pseudomonas aeruginosa as gram negative bacteria and Staphylococcus aureus as gram positive bacterium after 24 h incubation. The characterization studies showed that nano size homogenous biocereamic whitlockite (Ca 2.86 Mg 0.14 (PO 4) 2) was synthesized from the sea urchin skeleton. After dopping process, the main structure of the whitlockite keeps stable, showing a dopping concentration-independent character. On the other hand, the peaks belonging to ZnO were started to seen in the XRD pattern with increasing the level of ZnO-concentration (after 7 %). All experimental results point out that the obtained whitlockites are viable nominate candidates for bioceramic materials and the results of antibacterial sensitivity prove the inhibitory effect towards Escherichia coli , Pseudomonas aeruginosa and Staphylococcus aureus for ZnO-doped-whitlockite. [ABSTRACT FROM AUTHOR]

The present paper dealt with the performance analyses and improvement probabilities detection for the present geothermal power plant. In addition, the present study aimed to present an analysis methodology for manufacturers and users to detect deficiencies, inadequacies and probable improvements for a present system. In this study, a geothermal power plant was used as a sample system for the analyses. Analyses were applied to the plant regarding energy, exergy, economic and environmental aspects. After comprehensive analyses, it was observed that the power consumption of the fans shows dramatic change depending on the seasons. For this reason, if the location and site conditions of the facility are suitable, performing the cooling processes with water-cooled condensers instead of air-cooled condensers was suggested. Moreover, by keeping the acceptance of saturated steam inlet at the turbine, it is thought that an increase in system performance will be achieved by designing a pump system that can increase organic fluid pressures up to partially higher pressures. In addition to all these, it was recommended to analyse the effect of integrating a superheater to bring the organic fluid to the superheated vapour phase at the turbine inlet. • The performance analyses and improvement probabilities detection for a present geothermal power plant was made. • Numerical and experimental analyses of a single shaft double turbine binary organic Rankine cycle were applied. • Many important inadequacies were detected to present a wide vision to manufacturers and users. • A methodology for improvable components of the system was developed. • It was aimed to present performance analyses and performance improvement methodology for the researchers. [ABSTRACT FROM AUTHOR]

Highlights: [•] Radiation shielding properties of pumice materials are studied. [•] The relationship between physical, chemical and electro-kinetic properties pumice samples is identified. [•] The photon atomic parameters are important for the absorber peculiarity of the pumices. [ABSTRACT FROM AUTHOR]

• Synthesis of two novel electrochromic copolymers. • Effect of increasing EDOT amount on electrochromic behaviors. • Electrochemical and spectroelectrochemical characterizations of copolymers. In this study, two novel electrochromic copolymers (CoP1.3 and CoP1.5) were synthesized via electrochemical methods and characterized. The comonomers used in the synthesis were 3,4-ethylenedioxythiophene (EDOT) and a carbazole comprising monomer; 9-(2-(4-(Phenyldiazenyl) phenoxy) ethyl)-3,6-di(thiophen-2-yl)-9H-carbazole (M1). Carbazole containing monomer (M1) and EDOT were combined with two different comonomer feed ratios, 1: 3 and 1: 5 respectively in order to investigate the effect of increasing EDOT amount on electrochemical, spectroelectrochemical and electrochromic behaviors. The electrochemical and spectroelectrochemical characterizations of the electrochemically obtained copolymers were performed by cyclic voltammetry (CV) and UV–vis-NIR spectrophotometry. Both copolymers exhibited p-type doping with reversible oxidation potentials reported at 0.23 V/0.93 V for CoP1.3 and 0.30 V/0.98 V for CoP1.5. The difference between these oxidation potentials could be dedicated to the difference in electron density in the copolymer chains. Optical band gap values were calculated from neutral state absorptions as 1.21 eV and 1.18 eV for CoP1.3 and CoP1.5, respectively. Due to the higher EDOT amount in the copolymer backbone, the band gap for CoP1.5 is lower than that of CoP1.3. Both CoP1.3 and CoP1.5 exhibited multichromic behavior with different colors in the neutral and oxidized states. While both copolymers (CoP1.3 and CoP1.5) exhibited purple color in the neutral states, the colors turned to blue colors upon applied potentials. Optical contrast values were calculated as 31 % (at 555 nm), 55 % (at 1050 nm) and 38 % (at 1240 nm) for CoP1.3 and 34 % (at 565 nm), 25 % (at 975 nm) and 45 % (at 1170 nm) for CoP1.5. As a result of electrochromic switching studies, switching times (oxidation) were calculated as 2.5 s, 1.7 s, 1.9 s for CoP1.3 and 1.9 s, 1.8 s, 2.7 s for CoP1.5. Furthermore, addition of EDOT unit into copolymer backbone resulted in the obvious improvements in electrochemical, optical, electrochromic and kinetic properties. Copolymers exhibited full visible absorption with red-shifted neutral state absorption, lower optical band gap values compared to those of homopolymers. [ABSTRACT FROM AUTHOR]