Vše

Co hledáte?

Vše
Projekty
Výsledky výzkumu
Subjekty

Rychlé hledání

  • Projekty podpořené TA ČR
  • Významné projekty
  • Projekty s nejvyšší státní podporou
  • Aktuálně běžící projekty

Chytré vyhledávání

  • Takto najdu konkrétní +slovo
  • Takto z výsledků -slovo zcela vynechám
  • “Takto můžu najít celou frázi”

Filtry

36 486 (0,167s)

Výsledek výzkumu

Acidity of MCM-58 and MCM-68 zeolites in comparison with some other 12-ring zeolites

was tocharacterize the accessibility and acid strength of Lewis and Bronsted sites using FTIR spectroscopy. Pyridine adsorption allowed for quantification of Bronsted and Lewis acid acidic

CF - Fyzikální chemie a teoretická chemie

  • 2010
  • Jx
Výsledek výzkumu

Identification of the most active sites for tetrahydropyranylation in zeolites: MFI as a test case

with both Bronsted and Lewis acid-based catalysts, such as zeolites, considered. However and computational data clearly show that Bronsted acid sites are more reactive than Lewis acid si...

Physical chemistry

  • 2020
  • Jimp
  • Odkaz
Výsledek výzkumu

Enantioselective Allylation of Selected ortho-Substituted Benzaldehydes: A Comparative Study

We report a systematic study of the allylation of ortho-substituted benzaldehydes under catalysis of a Lewis base (N, N-dioxide), a Lewis acid (Keck allylation), and a Bronsted acid. ortho-Halobenzaldehyde...

CC - Organická chemie

  • 2014
  • Jx
  • Odkaz
Výsledek výzkumu

Surface reactivity of non-hydrolytic silicophosphate xerogels: a simple method to create Bronsted or Lewis acid sites on porous supports

matrices with Bronsted (RP-OH) and Lewis (tetracoordinated Al) acid functional groupsNon-hydrolytic sol-gel reactions of silicon acetates with trimethylsilyl (TMS) esters of phosphoric and phosphonic acids produce...

CA - Anorganická chemie

  • 2016
  • Jx
  • Odkaz
Výsledek výzkumu

Analysis of decisive structural parameters of zeolites for alkylation of benzene with ethylene

. The activity is controlled by the concentration of Bronsted acidic sites, while Lewis sitesThe effects of the zeolite structure and the Bronsted and Lewis sites by-products. It is shown that a three-dime...

Physical chemistry

  • 2020
  • Jimp
  • Odkaz
Výsledek výzkumu

Lewis Superacidic Tellurenyl Cation-Induced Electrophilic Activation of an Inert Carborane

The aryltellurenyl cation [2-(tBuNCH)C6H4Te](+), a Lewis super acid, and the weakly coordinating carborane anion [CB11H12](-), an extremely weak Bronsted acid (pK(a)=131.0 in MeCN), form an isolable ion pair comple...

Inorganic and nuclear chemistry

  • 2021
  • Jimp
  • Odkaz
Výsledek výzkumu

Enantioselective Allylation of beta-Haloacrylaldehydes: Formal Total Syntheses of Pteroenone and Antillatoxin

A comparative study of the catalytic allylations and crotylations of (E)-and (Z)-haloacrylaldehydes by Lewis bases (chiral N,N'-dioxides) and Bronsted acids (chiral phosphoric acids) was undertaken. The reactions p...

CC - Organická chemie

  • 2016
  • Jx
  • Odkaz
Výsledek výzkumu

Highly Functionalized Bronsted Acidic/Lewis Basic Hybrid Ferrocene Ligands: Synthesis and Coordination Chemistry

phosphanylcarboxylic acids and their corresponding aldehydes. These hybrid ambiphilic species that combine Bronsted-acidic and Lewis-basic functional moieties in their structure were......

Inorganic and nuclear chemistry

  • 2019
  • Jimp
  • Odkaz
Výsledek výzkumu

Alkaline Modification of MCM-22 to a 3D Interconnected Pore System and its Application in Toluene Disproportionation and Alkylation

of boththe Lewis and Bronsted acid site concentration., the accessibility/availability of Lewis acid sites, investigated by d (3)-acetonitrile treatments, while the Bronsted acidity decr...

CF - Fyzikální chemie a teoretická chemie

  • 2009
  • Jx
Výsledek výzkumu

Effect of Alkali-Free Synthesis and Post-Synthetic Treatment on Acid Sites in Beta Zeolites

and related Bronsted and Lewis acid sites. While calcination in ammonia preserves all of Bronsted acid sites and a decrease of the total concentration of Lewis sites suggested as a precursor of f...

Physical chemistry

  • 2020
  • Jimp
  • Odkaz
  • 1 - 10 z 36 486