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An alternative mercury-free voltammetric method based on the complexation of boron with alizarin red S (ARS) for the determination of boron using cobalt phthalocyanine modified carbon paste electrode (CoPcMCPE) was described. The parameters affecting peak current such as supporting electrolyte, pH, concentration of ARS and accumulation potential in the method using CoPcMCPE were determined as ammonium acetate-ammonia mixture, pH = 7.5, 1x10(-5) mol L-1 and -800 mV, respectively. The detection and quantitation limits of the method based on the standard deviation calculated from all points of the calibration equation for accumulation time of 0 and 30 s were calculated as 0.064 and 0.213 mg L-1, and 9.9 and 32.9 mu g L-1, respectively. The method was applied to the determination of boron in water samples with boron content. The accuracy and repeatability of the method were checked by applying the standard addition method for 30 s accumulation time, and by comparing the results obtained from Azomethine H method. The results obtained from two methods were compared by using student's t-test and no statistical difference was found between the results for 95% confidence level. The recoveries were calculated in the range of 99-104% and the relative standard deviations were below 10%, Research Project Unit of Balikesir University 2008/29

Balıkesir Üniversitesi, Fen Bilimleri Enstitüsü, Kimya Ana Bilim Dalı, Bu çalışmada, Alizarin Red S (ARS) ile kompleks oluşturabilen molibden ve bor'un voltammetrik tayin koşulları araştırılmış ve iki yeni voltammetrik yöntem geliştirilmiştir. Molibden tayini asılı cıva damla elektrodu (HMDE) yüzeyine adsorplanmış Mo(VI)-ARS kompleksindeki molibdenin indirgenmesinin persülfat tarafından katalizlenmesine dayanmaktadır. Bor tayini ise elektrot yüzeyine adsorplanmış B-ARS kompleksindeki ARS'nin kobalt ftalosiyanin modifiye karbon pasta elektrottaki (CoPc-CPE) yükseltgenmesi izlenerek gerçekleştirilmiştir. Ayrıca ARS'nin hem HMDE'daki ve hem de CoPc-CPE'daki voltammetrik davranışı da incelenmiştir. Molibden tayini için geliştirilen adsorptif katalitik sıyırma voltammetrik yöntemde pik akımını etkileyen parametreler destek elektrolit, pH; ARS derişimi, biriktirme potansiyeli ve persülfat derişimi sırasıyla asetik asit-fosforik asit karışımı, pH=4.25, 1.25x10-7 mol/L, 0 mV ve 1x10-3 mol/L olarak belirlenmiştir. Bu koşullarda elde edilen kalibrasyon grafiğinin denklemi Ip=62.899CMo+ 17.356 ve korrelasyon katsayısı 0.999 olarak bulunmuştur. Yöntemin belirtme alt sınırı ve tayin sınırı destek elektrolitin standart sapması esas alınarak sırasıyla 0.046 ve 0.150 µg/L olarak hesaplanmıştır. Yöntemin doğrusal aralığı 0.15-5.00 µg/L'dir. İçme suyu örneklerinde 1 ve 3 µg/L Mo derişimleri için gerikazanımlar sırasıyla %90 ve %93 ve 3 µg/L için bağıl standart sapma %2.88 olarak bulunmuştur. Yöntemde 100 µg/L As(III), Ni(II) ve Zn, 50 µg/L Al(III) girişim yapmamaktadır. Sb(III) ise ciddi girişim yapmaktadır. Bor tayini için geliştirilen CoPc-CPE'da adsorptif anodik sıyırma voltammetrik yönteminde pik akımını etkileyen parametreler destek elektrolit, pH; ARS derişimi, ve biriktirme potansiyeli sırasıyla amonyum asetat-amonyak karışımı, pH=7.5, 1x10-5 mol/L ve -800 mV olarak belirlenmiştir. Yöntemde biriktirme süresine bağlı olarak doğru denklemi ve doğrusal aralık değişmektedir. Biriktirme süresinin 0, 30 ve 60 saniye olduğu durumlar için elde edilen kalibrasyon grafiklerinin doğru denklemleri, korrelasyon katsayıları ve doğrusal aralıkları sırasıyla Ip=376.64CB+ 2982.10, r=0.998, 0.213-1.000 µg/L, Ip=11.0CB+ 1737.50, r=0.994, 32.9-70.0 µg/L ve Ip=500.23CB+ 2824.10, r=0.998, 0.26-1.00 µg/L'dır. Yöntemin belirtme alt sınırı ve tayin sınırı kalibrasyon grafiğinin tüm noktalarından hesaplanan standart sapma esas alınarak esas alınarak her bir biriktirme süresi için sırasıyla 0.064 ve 0.213 mg/L, 9.9 ve 32.9 µg/L ve 0.078 ve 0.259 µg/L olarak hesaplanmıştır. Yöntemin doğruluğu ve tekrarlanabilirliği 30 s biriktirme süresi için içme suyu örneklerinde standart katma yöntemi uygulanarak ve Azomethin H yöntemi ile kıyaslanarak test edilmiştir. Gerikazanım değerleri %99-104 aralığında ve yüzde bağıl standart sapmalar ise, In this study, voltammetric determination conditions of molybdenum and boron formed complex with Alizarin Red S (ARS) have been investigated and two new voltammetric method were developed. The method developed for determination of molybdenum is based on the catalizing of the reduction of molybdenum (VI) to molybdenum (V) in the Mo(VI)-ARS complex, adsorbed on the hanging mercury drop electrode (HMDE), by persulphate. The method developed for determination of boron was performed by monitoring the oxidation of ARS in the B-ARS complex adsorbed on the cobalt phthalocyanin modified carbon paste electrode (CoPc-CPE) surface. Additionally, the voltammetric behaviours of ARS were investigated at HMDE and CoPc-CPE. The parameters affected peak current such as supporting electrolyte, pH, accumulation potential and concentration of persulphate in the adsorptive catalytic stripping method developed for determination of molybdenum were determined as acetic acid-phosphoric acid mixture, pH=4.25, 1.25x10-7 mol/L, 0 mV ve 1x10-3 mol/L, respectively. The calibration equation and coefficient of correlation obtained at the optimum conditions were found as Ip=62.899CMo+ 17.356 and 0.999. The detection limit and quantitation limit of the method based on the standart deviation of blank were calculated as 0.046 ve 0.15 µg/L. The linear range of the method is 0.15-5.0 µg/L. The recoveries for 1 and 3 µg/L molybdenum in the drinking water samples were found as 90% and 93%, respectively. Relative standart deviation for 3 µg/L molybdenum is 2.88%. 100 µg/L As(III), Ni(II) and Zn, 50 µg/L Al(III) did not interfere while serious interference was observed from Sb(III). The parameters affected peak current such as supporting electrolyte, pH and accumulation potential in the adsorptive anodic stripping method using CoPc-CPE developed for determination of boron were determined as ammonium acetate-ammonia mixture, pH=7.5, 1x10-5 mol/L and -800 mV, respectively. The calibration equation and the linear range were different according to accumulation time used. The calibration equations, coefficient of correlation and the linear range obtained for accumulation time of 0, 30 and 60 s were found as Ip=376.64CB+ 2982.1 µg/L, r=0.998, 0.213-1.00 µg/L, Ip=11.0CB+ 1737.5, r=0.994, 32.9-70.0 µg/L ve Ip=500.23CB+ 2824.1, r=0.998, 0.26-1.0 µg/L, respectively. The detection limit and quantitation limit of the method based on the standart deviation calculated from all points of the calibration equation were calculated as 0.064 and 0.213 mg/L, 9.9 and 32.9 µg/L and 0.078 and 0.259 µg/L, respectively. The accuracy and repeatability of the method were checked by applying the standart addition method for 30 s accumulation time and by comparing the results obtained from Azomethin H method. The recoveries were calculated in the range of 99-104% and the relative standard deviations were, Bu çalışma Balıkesir Üniversitesi Rektörlüğü Bilimsel Araştırma Projeleri Birimi tarafından BAP 2008/29 Nolu Proje ile desteklenmiştir.

International audience; This study examined stocking with three early life stages of brown trout, Salmo trutta L., in the context of rehabilitating a native lineage. Experimental sections in five streams were stocked successively with three stages (I: unfed fry at the end of the reabsorption phase, II: fed fry measuring 2–3 cm and III: fed fry measuring 4–5 cm) derived from a hatchery stock bred from wild spawners. The three stages were distinguished by single or multiple fluoromarking of the otoliths with alizarin redS. The index of relative stocking efficiency was greater for stage II than for stage I in all sections and equivalent or greater than that for stage III. Stage II achieved significantly larger mean length and weight in autumn than stage III stockings.

Nakiboğlu, Nuri (Balikesir Author), A sensitive and selective voltammetric method for determination of antimony(III) using Alizarin Red S (ARS) as complexing agent is described. The method is based on the monitoring the oxidation peak of antimony(III)-ARS complex at -520mV in ammonium-ammonia buffer (pH=7.5). The peak current was measured by scanning the potential from -700mV versus Ag/AgClto more positive potentials without accumulation in the presence of 110-6molL-1 of ARS. The limit of detection (3s) and limit of quantification (10s) of the method were calculated from calibration curve as 1.45gL- and 4.8gL- respectively. The calibration plot for antimony(III) was linear in the range of 4.8-30gL-. The interference of various ions was examined. Serious interference from Al(III), Fe(III), Cu(II), Pb(II), and Zn(II) was eliminated by addition of EDTA to the solution. The method was applied to drinking water samples. The recoveries were in the range 94%-105%. The results obtained from the developed method were compared with those from the differential-pulse anodic-stripping method and no statistically significant difference was found.

Balıkesir Üniversitesi, Fen Bilimleri Enstitüsü, Kimya Ana Bilim Dalı, Bu çalışmada voltammetrik bor tayini için iki yeni yöntem geliştirilmiş ve bu yöntemler başta bor içerikli su örnekleri olmak üzere değişik örneklere uygulanarak yöntem geçerliliği araştırılmıştır. Bu yöntemlerden ilki, diferansiyel puls katodik sıyırma voltammetrisiyle sülfirik asitli ortamda, mannitol, bakır ve selenyum varlığında elde edilen As(V) pik akımının bor varlığında azalmasına dayanan dolaylı bor tayinidir. Burada As(V) pik akımı belirli bir derişim aralığında mannitol derişimi ile doğrusal değişmekte ve ortama bor ilave edildiğinde bor-mannitol kompleksinin oluşumu, As(V) pik akımında azalmaya neden olmaktadır. Yöntemin optimizasyonu için, pik akımındaki azalmayı etkileyen sülfirik asit derişimi, mannitol derişimi, As(V) derişimi, Cu(II) derişimi, Se(IV) derişimi, biriktirme potansiyeli ve biriktirme süresi parametreleri incelenmiş ve sırasıyla 0.1 mol/L, 0.1 mol/L, 0.8 mg/L, 22.5 mg/L, 40 µg/L, -550 mV (Ag/AgCl’e karşı) ve 90 s olarak bulunmuştur. Optimum koşullarda elde edilen kalibrasyon grafiğinin 9-100 mg/L aralığında doğrusal olduğu görülmüştür. Kalibrasyon grafiğinden belirtme sınırı 2.7 mg/L olarak hesaplanmıştır. Yöntemin bağıl standart sapması, (RSD) 10 mg/L bor varlığında (n = 7) % 2.6 bulunmuştur. Yöntem yüksek bor içerikli su örneklerine uygulanmış ve % 97-105 aralığında gerikazanım hesaplanmıştır. Elde edilen sonuçlar Azomethine-H yöntemiyle elde edilen sonuçlarla karşılaştırılmış ve istatistiksel olarak anlamlı bir fark bulunmamıştır. Geliştirilen ikinci yöntem, amonyum asetat/fosfat tamponunda (pH 7) borun Alizarin Red S (ARS) ile oluşturduğu kompleksin asılı civa damla elektrodu yüzeyine adsorpsiyonu ve potansiyelin anodik yönde taranması sonucunda -0.47 V’da komplekse ait yeni bir pik oluşumuna dayanmaktadır. Yöntemin optimum parametreleri araştırılmış ve destek elektrolit: amonyum asetat/fosfat tamponu (pH7), ARS derişimi: 1.10-6 mol/L, biriktirme potansiyeli: -700 mV(Ag/AgCl’e karşı) biriktirme süresi: 0 s, potansiyel tarama modu: diferansiyel puls, potansiyel tarama hızı: 5 mV/s olarak bulunmuştur. Optimum koşullarda elde edilen kalibrasyon grafiğinin 55-500 µg/L aralığında doğrusal olduğu görülmüştür. Yöntemin belirtme sınırı, 15 µg/L (S/N=3 alınarak) ve tayin sınırı 55 µg/L (S/N=10 alınarak) olarak hesaplanmıştır. Farklı iyonların girişim etkileri incelenmiş ve Al(III), Fe(III), Zn(II), Pb(II) ve Sb(III)’ün girişim yaptığı gözlenmiştir. Bunlardan Sb(III) dışındaki Al(III), Fe(III), Zn(II), ve Pb(II)’nun girişimi çözeltiye EDTA ilavesi ile giderilmiştir. Yöntemin bağıl standart sapması, 100 µg/L bor için % 5.1 (n=10) olarak bulunmuştur. Yöntem, Balıkesir’in zengin bor yataklarının bulunduğu Bigadiç ilçesinden alınan yüksek bor içerikli su ve Bandırma körfezinden alınan deniz suyu örneklerine uygulanmıştır. Bu örneklerde % 96-108 aralığında gerikazanım hesaplanmıştır. Elde edilen sonuçlar Azomethine-H yöntemiyle elde edilen sonuçlarla karşılaştırılmış ve istatistiksel olarak anlamlı bir fark bulunmamıştır., In this study, two novel methods were developed for voltammetric determination of boron and the validiation parameters of both the methods were investigated by applying them to various samples, mainly water samples with boron content. The former is an indirect method by differential pulse cathodic stripping voltammetry, based on the decrease of As(V) peak current which is obtained in the presence of mannitol, copper and selenium in the sulphuric acid medium. It was found that the As(V) peak current has changed linearly in the interval of particular mannitol concentration and the current has decreased due to the formation of boronmannitol complexes when boron was added to the solution. For the optimization of the method, the parameters those affect the decrease in the peak current such as the concentration of sulphuric acid, mannitol, As(V), Cu(II), and Se(IV), accumulation potential and the accumulation time were examined, and found to be 0.1 mol/L, 0.1 mol/L, 0.8 mg/L, 22.5 mg/L, 40 µg/L, -550 mV (versus Ag/AgCl) ve 90 s, respectively. It was seen that the the calibration curve obtained in the optimum conditions is linear in the range of 9-100 mg/L. The limit of detection was calculated from the calibration curve as 2.7 mg/L. Relative standard deviation (RSD) of the method was found to be as 2.6 % at the 10 mg/L boron level (n=7). The method was applied to high boron-containing top water samples and the recoveries were calculated in the range of 97-105 %. The results obtained from the developed method were compared with Azomethine-H method and no statistically significant difference was found. The second method developed is based on the monitoring the anodic peak of the boron-Alizarin Red S complex (ARS) at -0.47 V in ammonium acetate' phosphate buffer (pH 7). Here, boron complexes with Alizarin Red S (ARS) and the complex, as well as the free ligand, both adsorbs on a hanging mercury drop electrode. A new peak has appeared at -0.47 V by applying the potential towards to anodic direction. The optimum parameters of the method were investigated and found to be as follow: supporting electrolyte; ammonium acetate/phosphate (pH=7), concentration of ARS; 1.10-6 mol/L, accumulation potential; -700 mV (versus Ag/AgCl), accumulation time: 0 s, stripping mode: differential pulse, scan rate: 5 mV/s. It was seen that the the calibration curve obtained in the optimum conditions is linear in the range of 55-500 µg/L. The limits of detection (LOD) and quantifition (LOQ) based on signal to noise (S/N) ratio of 3 and 10 were 15 and 55 µg/L, respectively. The interference effects of the various ions were examined, and the interference from Al(III), Fe(III), Zn(II), Pb(II) and Sb(III) were observed. Except Sb(III), the interference of Al(III), Fe(III), Zn(II), and Pb(II) was eliminated by adding EDTA into the solution. The relative standard deviation (RSD) was found as 5.1 % for the 100 µg/L boron level (n = 10). The method was applied with satisfactorily results to the water samples with boron content collected from Bigadiç district of Balıkesir city and to the samples of seawater collected from Bandırma gulf. In those samples, the recoveries were calculated in the range of 96-108 %. The results obtained from the developed method were compared with Azomethine-H method and no statistically significant difference was found., Bu çalışma Balıkesir Üniversitesi Rektörlüğü Bilimsel Araştırma Projeleri Birimi tarafından BAP 2004/01 Nolu Proje ile desteklenmiştir.

Two procedures have been proposed and compared for separation and preconcentration of trace amounts of manganese, copper, and zinc in saline samples. The procedures are based in the use of Amberlite XAD-7 and an anion-exchanger Dowex 1X8-50 loaded with Alizarin Red S (ARS). In order to obtain quantitative recoveries of metal ions, various experimental parameters such as pH, shaking time, sample volume, amounts of solid phase, effects of concomitants, capacity and cations desorptions from solid phases were optimized. For Amberlite XAD-7 impregnated with ARS (XAD 7-ARS), Mn, Cu, and Zn were quantitatively retained, in the pH range 8.5-10.0, by using 0.50 g of solid phase, stirring time of 5 min and a total mass up to 200 µg of each cation. The sorbed elements were subsequently eluted with 5 mL of 3 mol L-1 HNO3, with recovering over 95%, and a fifty-fold preconcentration factor for Zn and a ten-fold preconcentration factor for Mn and Cu were obtained. For Dowex 1X8-50 impregnated with ARS (Dowex-ARS), Cu and Mn were quantitatively retained in the pH range 8.1 to 9.0, and Zn pH 8.1, by using 0.75 g of solid phase, 90 min of stirring time and a total mass up to 50 µg of each cation. The sorbed elements were subsequently eluted with 20 mL of 2 mol L-1 HNO3, and a five-fold preconcentration factor to Cu and Zn was obtained. The precision of the procedure was determined by running 10 replicate samples, each one containing 250 µg L-1 of each element and the relative standard deviations were 0.2% (Cu), 0.4% (Mn), and 0.4% (Zn), to XAD 7-ARS and 0.3% (Cu), 0.5% (Mn), and 0.3% (Zn), to Dowex-ARS. The procedures were used for determining of Mn, Cu, and Zn in physiological solutions and seawater samples, from Salvador-Bahia. The analyte addition technique was used and the recoveries obtained (³ 95%) revealed that the proposed procedure shows good accuracy and precision. Dois procedimentos foram comparados para separação e pré-concentração de traços de cobre, zinco e manganês em amostras salinas. Os métodos basearam-se na adsorção dos íons metálicos sobre duas fases sólidas obtidas por impregnação de uma resina não-iônica Amberlite XAD-7 e uma resina aniônica Dowex 1X8-50 com o reagente vermelho de alizarina S (ARS), ácido nítrico foi utilizado para re-extrair os cátions das fases sólidas, os quais foram determinados por FAAS. Para o sistema Amberlite XAD-7/ARS, Mn, Cu e Zn foram quantitativamente retidos, na faixa de pH de 8,5 a 10,0, para uma massa de 0,50 g da fase sólida, após 5 min de agitação e uma massa total de até 200 µg de cada metal. Os elementos foram eluídos com 5 mL de HNO3 3 mol L-1, com recuperação ³ 95%, obtendo-se fator de pré-concentração de até 50 vezes para Zn e de 10 vezes para Mn e Cu. Para o sistema Dowex 1X8-50/ARS, Cu, Mn e Zn foram quantitativamente retidos, na faixa de pH de 8,1 a 9,0 e Zn em pH 8,1, usando uma massa de 0,75 g da fase sólida, após 90 min de agitação e uma massa total de até 50 µg de cada metal. Os elementos foram eluídos com 20 mL de HNO3 2 mol L-1, obtendo-se fator de pré-concentração de até 5 vezes para Cu e Zn. A precisão dos procedimentos foi estabelecida pela medida de 10 replicatas com 250 µg L-1 de cada íon e os desvios padrão relativos foram de 0,2% (Cu), 0,4% (Mn), e 0,4% (Zn), para ARS-XAD7 e 0,3% (Cu), 0,5% (Mn), e 0,3% (Zn), para ARS-Dowex. Os procedimentos propostos foram aplicados na determinação de Mn, Cu e Zn em solução fisiológica e água do mar da cidade de Salvador/BA. Testes de recuperação com adição de 5 mg dos metais às amostras revelaram eficiência no que diz respeito à exatidão e a precisão dos procedimentos propostos, com recuperação quantitativa (³ 95%).

p. 212-218. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-01-10T19:58:34Z No. of bitstreams: 1 19936.pdf: 158639 bytes, checksum: 0b5ea51c475e6d267bd45eb460b5aa00 (MD5) Made available in DSpace on 2012-01-10T19:58:34Z (GMT). No. of bitstreams: 1 19936.pdf: 158639 bytes, checksum: 0b5ea51c475e6d267bd45eb460b5aa00 (MD5) Previous issue date: 2004 Two procedures have been proposed and compared for separation and preconcentration of trace amounts of manganese, copper, and zinc in saline samples. The procedures are based in the use of Amberlite XAD-7 and an anion-exchanger Dowex 1X8–50 loaded with Alizarin Red S (ARS). In order to obtain quantitative recoveries of metal ions, various experimental parameters such as pH, shaking time, sample volume, amounts of solid phase, effects of concomitants, capacity and cations desorptions from solid phases were optimized. For Amberlite XAD-7 impregnated with ARS (XAD 7-ARS), Mn, Cu, and Zn were quantitatively retained, in the pH range 8.5-10.0, by using 0.50 g of solid phase, stirring time of 5 min and a total mass up to 200 µg of each cation. The sorbed elements were subsequently eluted with 5 mL of 3 mol L-1 HNO3, with recovering over 95%, and a fifty-fold preconcentration factor for Zn and a ten-fold preconcentration factor for Mn and Cu were obtained. For Dowex 1X8–50 impregnated with ARS (Dowex-ARS), Cu and Mn were quantitatively retained in the pH range 8.1 to 9.0, and Zn pH 8.1, by using 0.75 g of solid phase, 90 min of stirring time and a total mass up to 50 µg of each cation. The sorbed elements were subsequently eluted with 20 mL of 2 mol L-1 HNO3, and a five-fold preconcentration factor to Cu and Zn was obtained. The precision of the procedure was determined by running 10 replicate samples, each one containing 250 µg L-1 of each element and the relative standard deviations were 0.2% (Cu), 0.4% (Mn), and 0.4% (Zn), to XAD 7-ARS and 0.3% (Cu), 0.5% (Mn), and 0.3% (Zn), to Dowex-ARS. The procedures were used for determining of Mn, Cu, and Zn in physiological solutions and seawater samples, from Salvador-Bahia. The analyte addition technique was used and the recoveries obtained (³ 95%) revealed that the proposed procedure shows good accuracy and precision. São Paulo

Alkan, Mahir (Balikesir Author), The present work describes a selective and rapid method for the determination of molybdenum with Alizarin Red S (ARS) in the presence of a water soluble polymer, poly(sulfonylpiperidinylmethylene hydroxide) (PSPMH). The ARS modified by PSPMH reacts with molybdenum(VI) in the solutions of pH 3.4-4.0 to produce a red complex. The composition of the complex is 1:4:1 mol ratio of Mo(VI): ARS:PSPMH. The complex obeys Beer's law from 0.05 to 5.50 mug ml(-1) with an optimum range. The molar absorptivity is 2.1 x 10(4) l mol(-1) cm(-1) at 500 nm. The interference effects of the foreign cations have been examined and it has been determined that only Cu(II), Al(III) and Fe(III) have to be masked by EDTA and tungsten can be tolerated till 4-fold of molybdenum in case of masking by citrate. The method has been applied to the determination of geological samples without solvent extraction or separation steps.

The original version of the article was published in Central European Journal of Chemistry, 2010, 8(2), 453–460, DOI: 10.2478/s11532-010-0003-5. Unfortunately, the original version of this article contains mistake, which we correct here.

The gliding arc discharge plasma (GAD) technique was used for discoloration and degradation of an anthraquinone dye Alizarin red S (ARS), an azo dye Orange G (OG) and their mixture. The influence of chloride and sulfate salts on the efficiency of treatment has also been studied. The aim of this study is the discoloration and degradation by GAD of ARS, and OG and their mixture. The GAD plasma generated between two moist air metallic electrodes connected to a high voltage produced chemical species and highly reactive molecules OH, NO , O , O 2 , HO 2 , H , H 2 O 2 , O 3 … and other excited-state neutral molecules. The reactions of discoloration for ARS and OG followed pseudo-first-order kinetics. The apparent kinetic constants of bleaching were found equal to 0.014 and 0.013 min −1 and degradation of 0.008 and 0.010 min −1 , respectively for the ARS and OG. For mixtures, the rate of discoloration was 80% in 120 min of treatment for mixtures III, IV and V, while the rate of COD reduction was fast in the first 30 min since it varied between 35% and 40% for all mixtures but stabilized at 68% toward the end of the treatment. The addition of chloride salts and sulfate showed a decrease in the effectiveness of treatment. GAD treatment is perfectly suited to dyes treatment. It is an alternative method that is part of green chemistry and sustainable development objectives.

Formation of a pink-coloured complex by the interaction of Cr (VI) and sodium alizarin-3-sulphonate (Alizarin Red S) has been reported. The chelate has maximum absorption. at 515 m\(\mu\). The composition, as determined by the method of continued variation using spectrophotometric mesurements, is indicated to be 1:1. The chelate is stable between pH 3.5 and 8.0. The stability has been determined by a method described by the authors and the values of logK and\(\bigtriangleup\)Fowork out respectively to be 4.72 ± 0.25 and -6.52 ± 0.35 kcal. at 250.

Background: Extracellular vesicle (EV)-derived microcalcifications formed in collagen-poor fibrous caps contribute to plaque rupture. Collagen accumulation and calcification are major determinants of plaque stability, although the mechanisms linking fibrotic and calcific responses are unknown. The collagen receptor discoidin domain receptor-1 (DDR-1) regulates plaque calcification in vivo; however, its role in the release of calcifying EVs remains unclear. We hypothesize that DDR-1 regulates the processes of fibrosis and EV-induced calcification in atherosclerotic plaques. Methods and results: Smooth muscle cells (SMC) from the carotid arteries of wild type and DDR-1 knockout (DDR-1-/-) mice (n=5 per group) were cultured in control or calcifying media. At days 14 and 21, cells were harvested and EVs isolated for analysis. Compared to wild type cells, DDR-1-/- SMCs exhibited a 3.5-fold increase in EV release (p