نتایج جستجو برای: catalyst

تعداد نتایج: 44027  

Journal: :Nanoscale 2014
E Shawat V Mor L Oakes Y Fleger C L Pint G D Nessim

Here we demonstrate an approach to enhance the growth of vertically aligned carbon nanotubes (CNTs) by including a catalyst reservoir underneath the thin-film alumina catalyst underlayer. This reservoir led to enhanced CNT growth due to the migration of catalytic material from below the underlayer up to the surface through alumina pinholes during processing. This led to the formation of large F...

2006
SABRI MAHMOUD

Abstraet--Jordanian natural kaolin and bentonite show good catalytic activity towards debutylating 2tert-butylphenol, and varying debutylation vs. isomerization selectivity after acid activation. The resulting catalytic activity of these samples is dependent on the acid employed for activation; the samples treated with acetic acid showed relatively low conversions, whereas those treated with hy...

2009
Ulla Létinois

The selective hydrogenation of dimedone (1) to the corresponding monoketone 2 over palladium and Amberlyst 15 ® is reported. The product is a synthetic building block for the fragrance and pharmaceutical industry. Advantages of the new catalytic procedure are the high catalyst activity and selectivity, less by-product formation, avoidance of the presence of acid, and consequently, less salt for...

2015
P. Kanta Rao Jose L. Contreras

The effect of transition metal doping on Pt/Al2O3 catalyst used in propane dehydrogenation reaction at 500 ̊C was studied. The preparation methods investigated were sequential impregnation (Pt followed by the 2 metal or the 2 metal followed by Pt) and co-impregnation. The metal contents of these catalysts were fixed as the weight ratio of Pt per the 2 metal of around 0.075. These catalysts were ...

1996
Z. Sun T. Örs B. G. Evans

This paper presents the performance studies of ATM via satellite based on experiments implemented by the RACE II CATALYST project R2074. The purpose of the project was to develop an ATM satellite link for the future B-ISDN services, particularly for the interconnections of the ATM testbeds which are in the form of broadband islands. Then initial ATM based B-ISDN can be introduced by interconnec...

Journal: :journal of nanostructures 2015
h. khojasteh v. mirkhani m. moghadam s. tangestaninejad i. mohammadpoor-baltork

palladium is the best metal catalyst for suzuki cross coupling reaction for synthesize of unsymmetrical biaryl compounds. but its high cost limits its application in wide scale. using of nanoscale particles as active catalytic cites is a good approach for reducing needed noble metal. by loading precious nanoparticles on magnetic nanocores as a support, recycling and reusing of catalyst will be ...

2014
Ryan O'Hayre Kevin N. Wood Svitlana Pylypenko Arrelaine A. Dameron Tim S. Olson Guido Bender Huyen N. Dinh Thomas Gennett Ryan M. Richards

Effect of nitrogen post-doping on a commercial platinum–ruthenium/carbon anode catalyst Report Title This work investigates the effects of after-the-fact chemical modification of a state-of-the-art commercial carbonsupported PtRu catalyst for direct methanol fuel cells (DMFCs). A commercial PtRu/C (JM HiSPEC-10000) catalyst is post-doped with nitrogen by ion-implantation, where “post-doped” den...

Journal: :Journal of the American Chemical Society 2004
Bradley A Steinhoff Ilia A Guzei Shannon S Stahl

The Pd(OAc)(2)/pyridine catalyst system is one of the most convenient and versatile catalyst systems for selective aerobic oxidation of organic substrates. This report describes the catalytic mechanism of Pd(OAc)(2)/pyridine-mediated oxidation of benzyl alcohol, which has been studied by gas-uptake kinetic methods and (1)H NMR spectroscopy. The data reveal that turnover-limiting substrate oxida...

2015
Tomoyo Goto Toshio Itoh Takafumi Akamatsu Woosuck Shin

The CO sensing properties of a micro thermoelectric gas sensor (micro-TGS) with a double AuPtPd/SnO₂ and Pt/α-Al₂O₃ catalyst were investigated. While several nanometer sized Pt and Pd particles were uniformly dispersed on SnO₂, the Au particles were aggregated as particles measuring >10 nm in diameter. In situ diffuse reflectance Fourier transform Infrared spectroscopy (DRIFT) analysis of the c...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید