oxime

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1 - Application of a dioxime-PVC electrode to potentiometric studies of Cr(III) ion
H. Aghaie M. H. Felcri M. Arvand K. Zare M. Aghaie

A PVC membrane Cr(III) ion selective electrode has been constructed using 2H-1,4-benzothioazine-2,3(4H)dione dioxime (BTD) as membrane carrier. The influence of membrane composition on the electroderesponse was studied. The electrode exhibits a Nernstian response over a چکیده کامل

A PVC membrane Cr(III) ion selective electrode has been constructed using 2H-1,4-benzothioazine-2,3(4H)dione dioxime (BTD) as membrane carrier. The influence of membrane composition on the electroderesponse was studied. The electrode exhibits a Nernstian response over a Cr(III) concentration range of 1.0 x10 6 to 1.0>< 10-1 M (r = 0.99) with a slope of 19.5 ± 0.5 mV per decade of concentration, and a detection limitof 8.9 x le M. The selectivity coefficient values as determined by separate solution method (SSM) indicateexcellent selectivity for Cr(III) ion over a large number of other ions. Applications of the proposed electrode tothe determination of Cr(III) in real samples and as an indicator for potentiometric titration of Cr(III) ion withEDTA, are reported. پرونده مقاله

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2 - Chromium(III) ion selective electrode based on 2H-1,4-benzothioazine-2,3(4H)dione dioxime as a neutral carrier
M.H. Fekri M. Darvishpour E. Baghdar

A poly(vinyl chloride) membrane based on a new a-dioxime derivative as membrane carrier was prepared andinvestigated as a Cr(III) selective electrode. The electrode exhibits a good potentiometric response for Cr(III)over a wide concentration range 1.0 x 10-6 to 1.0 x 10 چکیده کامل

A poly(vinyl chloride) membrane based on a new a-dioxime derivative as membrane carrier was prepared andinvestigated as a Cr(III) selective electrode. The electrode exhibits a good potentiometric response for Cr(III)over a wide concentration range 1.0 x 10-6 to 1.0 x 10-1 M with a slope 19.5+0.5 mV/decade and low detectionlimit of 8.9 x 10-7 M. It has a fast response time < 15 s. The best performance was observed with the membrancehaving the PVC-ligand-acetophenone-oleic acid composition 6:1:13:1. The proposed electrode works well in awide p1-1 range 1.5-5.5. The proposed sensor was successfuly used for the determination of Cr(III) ions insamples and real samples and as indicator electrode in potentiometric titration of Cr(III) ion. The application ofthis electrode for Cr(III) determination in real samples is described. The results obtained with this procedure arein close agreement with those obtained using AA spectrophotometry. پرونده مقاله

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3 - Chromium (III) ion selective electrode based on di(benzylamino)glyoxime
M. Kia H. Aghaie M. Arvand K. Zare M. Aghaie

A new poly(vinylchloride) membrane sensor for Cr3+ ions based on di (benzylamino)glyoxime asan ionophore was prepared. The electrode has a linear dynamic range 1×10-6-1×10-1 mol l-1,with aNernstian slope of 20.3 ± 0.5 mV per decade and a detection lim چکیده کامل

A new poly(vinylchloride) membrane sensor for Cr3+ ions based on di (benzylamino)glyoxime asan ionophore was prepared. The electrode has a linear dynamic range 1×10-6-1×10-1 mol l-1,with aNernstian slope of 20.3 ± 0.5 mV per decade and a detection limit of 2×10-7. It has a fast responsetime of <15 s and can be used for at least 3 months without any considerable divergence inpotential. The proposed electrode revealed good sensitivity for Cr(III) over a wide variety of metalions and could be used in a pH range of 2-5.5. The proposed sensor was used for the determinationof Cr3+ ions in real samples such as tea leaves, coffee and cacao powder by direct potentiometry. پرونده مقاله

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4 - اندازه گیری نیکل در نمونه های زیست محیطی به روش فلوتاسیون اسپکتروفتومتری با استفاده از دی متیل گلی اکسیم
محمد هادی گیویان راد امیر حسین حقیقتی

در این مقاله یک روش ساده و بسیار گزینش پذیر ا برای جداسازی، پیش تغلیظ و اندازه گیری اسپکتروفتومتریک نیکل ارایه گردیده است. اساس این روش بر پایه فلوتاسیون کمپلکس نیکل و دی متیل گلی اکسیم بین فاز آبی و سیکلوهگزان در7=pH می باشد. پس از انحلال کمپلکس در کلروفرم، میزان نیکل چکیده کامل

در این مقاله یک روش ساده و بسیار گزینش پذیر ا برای جداسازی، پیش تغلیظ و اندازه گیری اسپکتروفتومتریک نیکل ارایه گردیده است. اساس این روش بر پایه فلوتاسیون کمپلکس نیکل و دی متیل گلی اکسیم بین فاز آبی و سیکلوهگزان در7=pH می باشد. پس از انحلال کمپلکس در کلروفرم، میزان نیکل درnm327 به روش اسپکتروفتومتریک اندازه گیری شــد. برای بررسی کارایی این روش در اندازه گیری سریع و آسان نیکل چند نمونه زیست محیطی از جمله پساب صنعتی، آب دریا و آب رودخانه با این روش مورد تجزیه قرار گرفت. همچنین جهت بررسی صحت روش ارایه شده میزان نیکل در این نمونه ها به روش جذب اتمی شعله ای نیز مجددا اندازه گیری شد که نتایج بیانگر کارایی بالای روش در اندازه گیری مقادیر ناچیز نیکل در نمونه های پیچیده زیست محیطی می باشد. با توجه به سادگی، ارزان بودن و استفاده حداقلی از حلال های زیان آور آلی، این روش می تواند به عنوان روشی رایج در آزمایشگاه های زیست محیطی و صنایع به کارگرفته شود. پرونده مقاله

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5 - Immobilization of Cobaloxime on MCM- 41
Goldasteh Zarei Forouzan Zonouzi

This work reports, immobilization the Cobaloxime [Co (DH) Cl;DH,dimethylglyoximato)] onto the MCM- .The surface of MCM- was initially functionalized with -aminopropyltrimethoxysilane and -pyridine. For the electrostatic immobilization this was reacted with Cobaloxime an چکیده کامل

This work reports, immobilization the Cobaloxime [Co (DH) Cl;DH,dimethylglyoximato)] onto the MCM- .The surface of MCM- was initially functionalized with -aminopropyltrimethoxysilane and -pyridine. For the electrostatic immobilization this was reacted with Cobaloxime and immobilization was achieved by an electrostatic interaction between the Co Cobaloxime and the N of the pyridine and NH amine. Additional information was obtained by powder X-ray diffraction (XRD), BET, ICP and DR-UV-Vis, FT-IR spectroscopy. پرونده مقاله

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6 - Rapid, convenient and solventless green approach for the synthesis of aryloximes using ZnO nanoparticles as an efficient catalyst
Leila Dinparast Hassan Valizadeh

Freshly prepared ZnO nanoparticles were used as an effective heterogeneous base catalyst for the synthesis of aryloximes. The conversion of arylaldehydes and arylketones into the corresponding oximes (up to quantitative yields) was achieved by simply mixing the liquid r چکیده کامل

Freshly prepared ZnO nanoparticles were used as an effective heterogeneous base catalyst for the synthesis of aryloximes. The conversion of arylaldehydes and arylketones into the corresponding oximes (up to quantitative yields) was achieved by simply mixing the liquid reactants and hydroxylamine hydrochloride with ZnO nanoparticles under solvent-free condition. The procedure was carried out under wet conditions for solid reactants. The advantages of this method include mild reaction conditions, one-pot procedure, operational simplicity and use of inexpensive and non-toxic catalyst. پرونده مقاله

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7 - An efficient and selective method for conversion of oximes, semicarbazones and phenylhydrazones to the corresponding carbonyl compounds under solvent-free conditions
Khadijeh Yadollahzadeh Mahmoud Tajbakhsh

o-Xylylenebis (triphenylphosphonium peroxymonosulfate) (1) was easily prepared from an aqueous solution of oxone and o-xylylenebis- (triphenylphosphonium bromide). This Compound (1) is a useful and selective reagent for conversion of oximes, semicarbazones and phenylhyd چکیده کامل

o-Xylylenebis (triphenylphosphonium peroxymonosulfate) (1) was easily prepared from an aqueous solution of oxone and o-xylylenebis- (triphenylphosphonium bromide). This Compound (1) is a useful and selective reagent for conversion of oximes, semicarbazones and phenylhydrazones to the corresponding carbonyl compounds. The reaction was carried out under solvent-free conditions and in the presence of catalytic amount of aluminium chloride. This method shows a good selectivity in oxidation of oximes, semicarbazones and phenylhydrazones in the presence of aliphatic and aromatic alcohols. The advantages of the present method include good functional group tolerance, high yields of products, simple experimental procedure and purification, no solvent and short reaction times. پرونده مقاله

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8 - Synthesis of functionalized aryl-alkenes catalyzed by CN-ortho-palladated complex of 2,3-dimethoxybenzaldehyde oxime under microwave irradiation
Fatemeh Rafiee Abdol Reza Hajipour

A new dimeric orthopalladated complex was synthesized via reaction of 2,3-dimethoxy benzaldehyde oxime with palladium chloride and lithium chloride in methanol as solvent and sodium acetate as base at room temperature. The catalytic activity of this dimeric [Pd{C6H2(-CH چکیده کامل

A new dimeric orthopalladated complex was synthesized via reaction of 2,3-dimethoxy benzaldehyde oxime with palladium chloride and lithium chloride in methanol as solvent and sodium acetate as base at room temperature. The catalytic activity of this dimeric [Pd{C6H2(-CH=NOH)-(OMe)2-2,3}(µ-Cl)]2 complex as an efficient, air, and moisture tolerant catalyst was investigated in Mizoroki–Heck cross coupling reaction of various aryl halides and also arenesulfonyl chloridesas the electrophilic partners with different coupling partner alkenes such as methylacrylate, methylmetacrylate and styrene . The combination of homogenous metal catalyst, microwave irradiation, and microwave-active polar solvents gave high yields of functionalized aryl-alkene products in short reaction times. پرونده مقاله

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9 - Nano SiO2/H2SO4 as catalyst for the Beckmann rearrangement and deoximation of aldoximes
Marziyeh Bagheri Mostafa Karimkoshteh

Nano silica-H2SO4 is an efficient and mild catalysis system for the regeneration of aldehyde from aldoximes. Ketoximes are converted to amides by Beckmann rearrangement in the presence of nano silica-H2SO4. The reactions are carried out in solvent-free conditions under چکیده کامل

Nano silica-H2SO4 is an efficient and mild catalysis system for the regeneration of aldehyde from aldoximes. Ketoximes are converted to amides by Beckmann rearrangement in the presence of nano silica-H2SO4. The reactions are carried out in solvent-free conditions under microwave irradiation (600 W) within 50-120 sec in good yields. پرونده مقاله

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