توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱The false sero–negativity of brucella standard agglutination test: Prozone phenomenon
اطلاعات انتشار: سيزدهم،شماره۶۶-۶۷، فروردين و ارديبهشت ، سال
تعداد صفحات: ۵

۲Covalently Grafted on to the Glassy Carbon Electrode in Non–Aqueous Media of Apigenin and Naringenin as Different Flavonoid Derivatives
اطلاعات انتشار: Analytical & Bioanalytical Electrochemistry، سوم،شماره۲، Apri۲۰۱۱، سال
تعداد صفحات: ۱۷
In this paper, apigenin (AG) and naringenin (NG) have been studied with the cyclic voltammetric technique using the glassy carbon (GC) electrode. The modification was carried out only in non–aqueous media, while the electrochemical characterization was done in both aqueous and non–aqueous media. 0.1 M tetrabutylammonium tetrafluoroborate (TBATFB) in acetonitrile (MeCN) was used in non–aqueous experiments, Britton–Robinson (BR) buffer solution (pH=2) and 0.1 M KCl solution were used in aqueous experiments. Surface modification experiments were performed in the +0.3 V and +2.8 V potential ranges with a scan rate of 0.1 Vs–1 and 10 cycles for two molecules. The presence of AG and NG at the GC electrode surface was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), contact angle measurement (CAM) technique and atomic force microscopy (AFM). We also investigated the electrochemical oxidation of AG and NG in non–aqueous media and propose a grafting mechanism of AG and NG to the GC electrode surface.

۳Glassy Carbon Electrode Modified with 4,4'–Oxydiphenylene Bisdiazonium Tetrafluoroborate as a Sensitive Voltammetric Sensor for Flavonoids
نویسنده(ها): ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: Analytical & Bioanalytical Electrochemistry، سوم،شماره۶، Dec ۲۰۱۱، سال
تعداد صفحات: ۱۴
In the current study, the electrochemical behaviors of 4,4'–oxydianiline and 4,4'– oxydiphenylene bisdiazonium tetrafluoroborate salt on the surface of glassy carbon electrode using voltammetry technique. 1 mM 4,4'–oxydianiline in 100 mM tetrabutylammonium tetrafloroborate (in acetonitrile) has been modified to the electrode surface in 0.0 mV and +1800 mV potential range at 100 mV s–1 scanning rate with 50 cycles. The same solvent has been used for 4,4'–oxydiphenylene bisdiazonium tetrafluoroborate salt. 1 mM prepared , '– oxydiphenylene bisdiazonium tetrafluoroborate salt has been modified to the electrode surface in +100 mV and –1200 mV potential range using 100 mV s–1 scanning rate with 10 cycles. Following the modification and characterization process, the sensitivity of 4,4'–oxydiphenylene bisdiazonium tetrafluoroborate salt modified glassy carbon electrodehas been tested against flavones, 3–hydroxyflavone, quercetin, rutin and naringenin. Based on the sensitivity tests, 4,4'–oxydiphenylene bisdiazonium tetrafluoroborate salt modified glassy carbon electrode can be used in the determination of total antioxidant capacity. The further studies will progress through this way. Cyclic voltammetry technique has been utilized for the modification process. Electrochemical impedance spectroscopy and scanning electron microscopy have been used for the characterization process.

۴Electrochemical Grafting by Reduction of 4–Methylaminobenzenediazonium Salt at GC, Au and Pt Electrode: Investigation of Sensitivity Against Phenol by Cyclic Voltammetry
اطلاعات انتشار: Analytical & Bioanalytical Electrochemistry، چهارم،شماره۴، Aug ۲۰۱۲، سال
تعداد صفحات: ۱۵
The aim of this study is to modify a glassy cabon, gold and platinum electrode with 4–methylaminobenzenediazonium salt (MABDAS) to evaluate the possible application on the detection of phenol by cyclic voltammetry (CV). Diazonium salt was reduced electrochemically and covalently electro–grafted onto GC, Au and Pt electrodes surface to form modified electrodes in non–aqueous media. The electrode surfaces were modified with MABDAS in acetonitrile (CH3CN). MAB modified GC (MAB\GC) electrode was used for the phenol determination in aqueous media. The effect of pH on the electrochemical behavior of the modified GC electrode was investigated for the phenol detection.

۵Effect of expanded perlite aggregate on cyclic thermal loading of HSC and artificial neural network modeling
نویسنده(ها): ، ، ، ، ، ،
اطلاعات انتشار: Scientia Iranica، نوزدهم،شماره۱، ۲۰۱۲، سال
تعداد صفحات: ۱۰
This paper describes a laboratory investigation of the resistance to freezing and thawing of Expanded Perlite Aggregate (EPA) concrete, compared with that of natural aggregate concrete. The effects of EPA ratios on High Strength Concrete (HSC) properties were studied for 28 days. EPA replacements of fine aggregate (0–2 mm) were used: 10%, 20% and 30%. The properties examined included compressive strength, Ultrasound Pulse Velocity (UPV), porosity, microstructure and the Relative Dynamic Modulus of Elasticity (RDME) of HSC. Results showed that the compressive strength, UPV and RDME of samples were decreased with an increase in EPA ratios. Test results revealed that HSC was still durable after 100, 200 and 300 cycles of freezing and thawing in accordance with the ASTM C666. After 300 cycles, reduction in compressive strength and RDME ranged from 7% to 29% and 5% to 21%, respectively. In this paper, feed–forward Artificial Neural Network (ANNs) techniques were used to model the relative change in compressive strength and UPV in cyclic thermal loading. Genetic algorithms were applied in order to determine optimum mix proportions subjected to 300 thermal cycling. The best performance was obtained from HSC with about 10% EPA.

۶Effect of expanded perlite aggregate on cyclic thermal loading of HSC and artificial neural network modeling
نویسنده(ها): ، ، ، ، ، ،
اطلاعات انتشار: Scientia Iranica، نوزدهم،شماره۱، ۲۰۱۲، سال
تعداد صفحات: ۱۰
This paper describes a laboratory investigation of the resistance to freezing and thawing of Expanded Perlite Aggregate (EPA) concrete, compared with that of natural aggregate concrete. The effects of EPA ratios on High Strength Concrete (HSC) properties were studied for 28 days. EPA replacements of fine aggregate (0–2 mm) were used: 10%, 20% and 30%. The properties examined included compressive strength, Ultrasound Pulse Velocity (UPV), porosity, microstructure and the Relative Dynamic Modulus of Elasticity (RDME) of HSC. Results showed that the compressive strength, UPV and RDME of samples were decreased with an increase in EPA ratios. Test results revealed that HSC was still durable after 100, 200 and 300 cycles of freezing and thawing in accordance with the ASTM C666. After 300 cycles, reduction in compressive strength and RDME ranged from 7% to 29% and 5% to 21%, respectively. In this paper, feed–forward Artificial Neural Network (ANNs) techniques were used to model the relative change in compressive strength and UPV in cyclic thermal loading. Genetic algorithms were applied in order to determine optimum mix proportions subjected to 300 thermal cycling. The best performance was obtained from HSC with about 10% EPA.

۷Population structure, growth and reproduction of leaping grey mullet (Liza saliens Risso, 1810) in Beymelek Lagoon, Turkey
نویسنده(ها): ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: IRANIAN JOURNAL OF FISHERIES SCIENCES، دهم،شماره۲، Apr ۲۰۱۱، سال
تعداد صفحات: ۱۲
Population structure, growth, length–weight relationship and reproduction characteristics of leaping grey mullet (Liza saliens (Risso, 1810) were investigated in Beymelek Lagoon from February 2006 to January 2007. During the study, a total of 1248 leaping grey mullet were captured by gill– and trammel nets of various mesh sizes. Male to female ratio for leaping grey mullet population in Beymelek Lagoon was 1:2.71. The ages ranged from 1 to 4 years for males and from 0 to 5 years for females. The growth parameters of the von Bertalanffy equation were: L∞ = 35.2 cm, K = 0.276 year–1 and t0 = –2.893 year for males, L∞ = 35.9 cm, K = 0.386 year–1 and t0 = –1.760 year for females and L∞ = 39.9 cm, K = 0.271 year–1 and t0 = –2.233 year for all individuals. The calculated length–weight equations were W = 0.0061*L3.124 for males, W = 0.0060*L3.124 for females and W = 0.0099* L2.954 for all individuals. The slope (b) values of the length–weight relationship showed that weight of leaping grey mullet in Beymelek Lagoon increased with length in isometric. The mean condition factor for males, females and all specimens were determined as 0.908, 0.900 and 0.897, respectively. According to sex groups, the mean condition factor of males was slightly higher than that of females. The total length at 50% maturity for female leaping grey mullet was determined as 23.3 cm. It was assumed that spawning period for this species was from May to July.

۸The effects of physicochemical parameters on fish distribution in Eğirdir Lake, Turkey
نویسنده(ها): ، ، ، ، ، ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: IRANIAN JOURNAL OF FISHERIES SCIENCES، پانزدهم،شماره۲، Apr ۲۰۱۶، سال
تعداد صفحات: ۱۲
The present study was conducted based on the fish species and physicochemical parameters of Eğirdir Lake. Sampling was carried out monthly from January through December 2010 between 9 am and 11 am. The parameters measured were water temperature, depth, secchi disk depth, turbidity, dissolved oxygen, saturation of dissolved oxygen, pH, conductivity, chloride, hardness, calcium, magnesium, bicarbonate, carbonate, nitrate, nitrite, ammonium, sulphate, phosphate, silica, organic substance, acid power (SBV) and chlorophyll–a. Monthly sampling was performed at four stations at different depths. Water temperature ranged from 6.9±0.5 °C in February to 26.8±0.4 °C in August. Minimum secchi disk depth recorded was 0.5 m while the maximum was 2.4 m. Dissolved oxygen ranged from 4.2±0.2 to 12.6±0.6 mgL–1. The pH values ranged from 8.4 to 9.6. In this study, 15 fish species, belonging to eight families were identified. Among the 15 fish species recorded, Cyprinidae was the dominant family followed by Percidae (3 %). According to detrended correspondence analysis (DCA), variables were able to explain 90 % of total variation suggesting a significant result. The results showed that water temperature, dissolved oxygen and saturation of dissolved oxygen were the most important physicochemical parameters affecting fish distribution. Other pyhsicochemical parameters of this lake did not show any significant statistical differences in determining fish distribution.
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