in the present study, a new gas diffusion electrode (gde) (based on pt/nafion membrane) is fabricated. the electrochemical results show that the new gde has the highest electrochemical activity toward the oxygen reduction reaction (orr) among the three electrodes. the sem and xrd findings show that a platinum layer can be attached to nafion membrane closely and firmly with a strong peak corresp...

1 يوجشناد سانشراک ی ،هیذغت مولع دشرا ،نارهت یکشزپ مولع هاگشناد ،یسانش میژر و هیذغت هدکشناد ناریا 2 لوئسم هدنسیون : هورگ رایداتسا هیذغت هعماج ،ناریا ،نارهت یکشزپ مولع هاگشناد ،یسانش میژر و هیذغت هدکشناد ، یکینورتکلا تسپ : [email protected] 3 داتسا هورگ هیذغت هعماج هدکشناد، هیذغت میژرو هاگشناد،ینامرد مولع یکشزپ ،نارهت ناریا 4 يارتکد تملاس تاقیقحت یلم وتیتسنا ،ناهفصا یتشادهب ت...

in this work, sol-gel processing was used to synthesize the fluorohydroxyapatite (nano-fha, ca10(po4)6(oh)2−xfx) nanopowders. the advantages of the sol-gel method over other methods are precise control of composition, low processing temperature, and better homogeneity. calcium nitrate tetrahydrate, phosphorous pentoxide and tetrabuthylammonium fluoride were used, respectively, as p, ca, and f p...

the aim of this study is to evaluate the influence of ph on the synthesis of nanocrystallines cobalt ferrite by combination of sol- gel auto combustion and ultrasonic irradiation methods. two different fuels, urea and thiourea, along with metal nitrates (oxidant) were used to prepare cofe2o4 powders. the morphology of the resulting powders was investigated. the powders were characterized by x-r...

هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 23 دنفسا 1392 :شریذپ 15 تشهبیدرا 1393 :تیاس رد هئارا 19 رهم 1393 رد اب هلاقم نیا رد يور مسج لمح يارب ریسم بیقعت یقیبطت لرتنک ،مسج نتفرگ نیح رد مسج و تابر کی هجنپ نیب شزغل ناکما نتفرگ رظن کت تابر کی طسوت نیمز رارق یسررب دروم یتشگنا یسررب يارب یبسانم هنومن ،متسیس نیا .تسا هتفرگ شور ياه فلتخم لیلحت دننام یحارط لرتنک هدننک اه رد تابر متسیس ماسجا ...

عاطقلا طبر ي يذ لا ة يبرهكلا ىو قلا ماظنل يكيمانيدلارارقتسلال ةضيفتسم ةيلمع ةسارد ثحبلا اذه مدقي ني ب ة لوقنملا ةرد قلا ةدا يز ى لع ك لذ ريثأ ت و ةيدوعس لا ءا برهآ ةآر ش ن م ط سولأا عا طقلا و يقرش لا نيعاطقلا ، ىوقلا مظن تاتبثم طبض للاخ نم كلذو . دقل شم ةغايص مت ةلك طبض ةروص ىف تاتبثملا هذه ةلثمأ ةلكشم . ماظنلا ءادأ نيسحتل ك لذو ةدر فنملا ماظنلا ميق ىلع نادمتعت فده يتلاد حارتقا مت دقلو . د قلو ...

يفكي هنأ نيبن ،ثحبلا اذه يف ةيقفأ حئارش تاطاقسإ هيمسن ام لثم باسحلا ةلهس ملاعم مادختسا ايلآ ةعوبطملا فورحلا ىلع يئوضلا فرعتلا ةلأسم ةءافكب لحت يكل ةيسأرو . ةرجش مادختساب فرعتلا متي حاجنلا لدعم ةدايزل ىرخأ تافاضإ عم ةدمعأو فوفص فذحو ميعنتو عوجر تايلآب ةموعدم رارق . و مدختسن ماظنلا بيردتل طخ نم زومر Times New Roman . دق فذحلاو ميعنتلاو عوجرلا ليعفت نإ لاًدعم ققح حجان اً زواجت 98 % نم لقأ فرعت نمزب ...

ZnGa2O4 nano crystals were prepared by an improved coprecipitation method, which we call ‘spray coprecipitation’. XRD results shows the resulting crystal size using the new method is under 10nm, whereas the powder prepared by ordinary coprecipitation is about 30nm. XRD results also shows ZnO peaks exists in ZnGa2O4 powder prepared by traditional coprecipitation, but disappears in ZnGa2O4 nano c...

A new organogelator, benzyl (4-methyl-1-oxo-1-(2-hexadecanoylhydrazinyl)pentan-2-yl)carbamate (designated as Cbz-Leu-HdHz), was designed and synthesized, which could self-assemble in many organic solvents and form the thermally reversible physical supramolecular organogels. The gel-sol phase transition temperatures (TGS) were determined as a function of gelator concentration and the correspondi...

In the present endeavour, SnO2 nanoparticles (NPs) were synthesized using microwave method. Synthesized SnO2 NPs were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrscopy (EDS) to find their structure, morphology and elemental composition. SnO2 NPs were of spherical morphology having crystallite size of 35.42 nm as obtained from Scher...