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This study was conducted to determine the antioxidant and antimicrobial activities of methanol extract obtained from flower, leaf and root sections of endemic Adonis paryadrica (Boiss.) Kandemir & Aytaç stat. nova. naturally growing in the Turkish flora. The most efficient total phenolic compounds and flavonoid contents were obtained from leaf extract at 21.24 mg GAEs (gallic acid equivalent)/g dw and 54.97 mg REs (rutin equivalent)/g dw, respectively. Among the three different sections of this plant, leaf extracts showed the highest Cupric Reducing Antioxidant Power (CUPRAC) effect with 80.28 µmol TEs (trolox equivalent)/g dw. From the three different sections, the methanol extract of the leaf parts demonstrated strong antibacterial activity against Bacillus subtilis with a 16.1 mm zone diameter. These valuable and current findings from these precious plants, which constitute natural resources in terms of biodiversity, contribute innovative information to the literature on endemic plant species. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the antioxidant and antimicrobial activities of methanol extract obtained from flower, leaf and root sections of endemic Adonis paryadrica (Boiss.) Kandemir & Aytaç stat. nova. naturally growing in the Turkish flora. The most efficient total phenolic compounds and flavonoid contents were obtained from leaf extract at 21.24 mg GAEs (gallic acid equivalent)/g dw and 54.97 mg REs (rutin equivalent)/g dw, respectively. Among the three different sections of this plant, leaf extracts showed the highest Cupric Reducing Antioxidant Power (CUPRAC) effect with 80.28 µmol TEs (trolox equivalent)/g dw. From the three different sections, the methanol extract of the leaf parts demonstrated strong antibacterial activity against Bacillus subtilis with a 16.1 mm zone diameter. These valuable and current findings from these precious plants, which constitute natural resources in terms of biodiversity, contribute innovative information to the literature on endemic plant species. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effectiveness of conceptual change texts supplemented instruction on students' understanding of electrochemistry and their attitudes towards chemistry. The participants of the study consisted of 45 junior students of a public high school. Two classes were randomly assigned as experimental and control groups. Experimental group received conceptual change texts supplemented instruction. On the other hand, control group received instruction in which lecturing, questioning and discussion methods with no consideration of the misconceptions were used. The study lasted in 3-weeks period. A 24-item multiple choice test that was developed by the researcher was administered to assess students' conceptual understanding of electrochemistry. Meanwhile attitude scale toward chemistry was provided to both groups as a pre and post tests. As a result, it was obtained that there was no significant difference between groups on understanding of electrochemistry concepts and their attitudes towards chemistry as a school subject. [ABSTRACT FROM AUTHOR]

This paper reviews the history of phthalocyanines in Turkey. Phthalocyanines are chemical compounds that were accidently discovered nearly a century ago. The relevant research and articles have grown dramatically in Turkey since our first paper on them containing four [15]crown[5] published in 1986. The ball-type phthalocyanines were produced and published as a new concept in phthalocyanine chemistry for the first time by our group in Turkey in 2006. Unfortunately, with the exception of our work on this subject, almost no papers have been published in Turkey or in other countries since then. We strongly urge scientists to consider working on this new type of phthalocyanine, which shows interesting development potential in electrical, electrochemical, and photovoltaic applications as well as oxygen reduction for fuel cells. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to investigate the electrochemical treatment of textile dye wastewater in the presence of NaCl electrolyte by using aluminium electrodes. Design/methodology/approach – The electrochemical treatment of textile dye wastewater was optimized using response surface methodology (RSM). RSM-based D-optimal design was employed to construct statistical models relating turbidity and designed effective parameters known as current density, electrolyte concentration and electrolysis time. The experimental plan consists of a three-factor (three numerical) matrix. Findings – The results show that the current density has significant effect on the reduction of turbidity. Besides, electrolysis time is the most influential factor on the turbidity. In order to enhance the electrochemical treatment performance, no coagulant addition or further physicochemical processes were employed. Originality/value – Industrial certain textile dye wastewater in Turkey is used to determine optimal values. [ABSTRACT FROM AUTHOR]

Abstract: International Center for Hydrogen Energy Technologies (ICHET) has been successfully promoting hydrogen and fuel cell technologies in Turkey. In addition to technology demonstrations, short-courses are affectively utilized throughout the country. A series of capacity building activities designed to increase the knowledge and awareness of engineering students, researchers, educators and policy makers has been implemented. Meeting activities include short courses, technology specific workshops and conferences, project sponsorships and summer schools. System integration for prototype demonstrations forms the basis for hand-on practical learning through university-industry collaboration in the laboratory. All these activities facilitate knowledge transfer, exchange of information at regional, national and international levels and involve academics, researchers, experts and service providers to further develop their knowledge and interest on hydrogen energy technologies in Turkey. [Copyright &y& Elsevier]

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In this study, a number of 15 organophoshorus (OP) insecticides were investigated in 275 honey samples in 33 different cities of Turkey, using gas chromatography electron capture detector. The limit of determination values was detected between 0.25 and 9.55 ng g(-1). The correlation coefficients obtained from calibration curves of the OP standards were found to be between 0.992 and 0.999. No insecticide residue was detected in the samples analyzed. This result is highly significant because of its impacts on public health and food safety.

The fluoride contents were determined by ion-selective electrode in 26 black tea samples originally produced in Turkey, Sri Lanka, India and Kenya, and in 14 herbal and seven fruit infusions originated from Turkey. Fluoride content in black tea infusions ranged from 0.57 to 3.72 mg/L after 5 min of brewing. Higher fluoride levels were found in black teas originated from Turkey when compared with teas originated from Sri Lanka. Moreover higher fluoride levels were determined in black tea bags compared with granular and stick-shaped black teas. However, herbal and fruit infusions were characterized by low values of fluoride (0.02-0.04 mg/L) after 5 min of brewing and increasing brewing time to 10 min caused only slight increases in some infusions. As a result, consuming tea infusions prepared from some black tea available in Turkish market, especially black tea bags, in large quantities may lead to exposion to a high amount of fluoride which may cause dental fluorosis. Although fruit and herbal infusions are safer to consume their fluoride contents are too low for caries prevention. In countries such as Turkey where tea is traditionally consumed, the fluoride concentration and daily safety precautions should be indicated on tea products.

The performance of electrocoagulation (EC) technique for decolorization and chemical oxygen demand (COD) reduction of anaerobically pretreated poultry manure wastewater was investigated in a laboratory batch study. Two identical 15.7-L up-flow anaerobic sludge blanket (UASB) reactors were first run under various organic and hydraulic loading conditions for 216 days. Effects of operating parameters such as type of sacrificial electrode material, time of electrolysis, current density, initial pH, and electrolyte concentration were further studied to optimize conditions for the post-treatment of UASB pretreated poultry manure wastewater. Preliminary tests conducted with two types of sacrificial electrodes (Al and Fe) resulted that Al electrodes were found to be more effective for both COD and color removals than Fe electrodes. The subsequent EC tests performed with Al electrodes showed that optimal operating conditions were determined to be an initial pH of 5.0, a current density of 15mA/cm(2), and an electrolysis time of 20min. The results indicated that under the optimal conditions, about 90% of COD and 92% of residual color could be effectively removed from the UASB effluent with the further contribution of the EC technology used as a post-treatment unit. In this study, the possible acute toxicity of the EC effluent was also evaluated by a static bioassay test procedure using guppy fish (Lebistes reticulatus). Findings of this study clearly indicated that incorporation of a toxicological test into conventional physicochemical analyses provided a better evaluation of final discharge characteristics.

In this paper, treatment of leachate by electrocoagulation (EC) has been investigated in a batch process. The sample of leachate was supplied from Odayeri Landfill Site in Istanbul. Firstly, EC was compared with classical chemical coagulation (CC) process via COD removal. The first comparison results with 348 A/m2 current density showed that EC process has higher treatment performance than CC process. Secondly, effects of process variables such as electrode material, current density (from 348 to 631 A/m2), pH, treatment cost, and operating time for EC process are investigated on COD and NH4-N removal efficiencies. The appropriate electrode type search for EC provided that aluminum supplies more COD removal (56%) than iron electrode (35%) at the end of the 30 min operating time. Finally, EC experiments were also continued to determine the efficiency of ammonia removal, and the effects of current density, mixing, and aeration. All the findings of the study revealed that treatment of leachate by EC can be used as a step of a joint treatment.

Lectin affinity chromatography was miniaturized into a microfluidic format, which results in improvement of performance, as compared to the conventional method. A lectin affinity monolith column was prepared in the microchannel of a microfluidic chip. The porous monolith was fabricated by UV-initiated polymerization of ethylene dimethacrylate (EDMA) and glycidyl methacrylate (GMA) in the presence of porogeneities, followed by immobilization of pisum sativum agglutinin (PSA) on the monolith matrix. Using electroosmosis as the driven force, lectin affinity chromatographies of three kinds of glycoprotein, turkey ovalbumin (TO), chicken ovalbumin (CO), and ovomucoid (OM), were carried out on the microfluidic system. All the glycoproteins were successfully separated into several fractions with different affinities toward the immobilized PSA. The integrated system reduces the time required for the lectin affinity chromatography reaction to approximately 3%, thus, the overall analysis time from 4 h to 400 s. Only 300 pg of glycoprotein is required for the whole separation process. Moreover, troublesome operations for lectin affinity chromatography are simplified.