نتایج جستجو برای: bed medium zeolite
تعداد نتایج: 293206 فیلتر نتایج به سال:
A d-dimensional zeolite is a d-dimensional body-and-pin framework with a (d+1)-regular underlying graph G. That is, each body of the zeolite is incident with d+1 pins and each pin belongs to exactly two bodies. The corresponding d-dimensional combinatorial zeolite is a bar-and-joint framework whose graph is the line graph of G. We show that a two-dimensional combinatorial zeolite is generically...
High-quality TMA-A zeolite nonocrystals were synthesized using a hydrothermal method from a Al(i-pro)3 : 2.2 TEOS : 2.4 TMAOH : 0.3 NaOH : 200H2O composition. The average size of the zeolite crystal used was 60-130 nm with a lattice constant of 12.389 Å. The well-oriented self-assembled monolayers of zeolite with a face parallel to the glass surface treated with the 4-diisocyanates (DIC-4) show...
Chiral zeolitic materials with intrinsically chiral frameworks are highly desired because they can combine both shape selectivity and enantioselectivity. In the field of zeolite, the synthesis of chiral polymorph A of zeolite Beta or chiral polymorph A-enriched zeolite Beta is one of the biggest challenges. We demonstrate here a generalized extremely concentrated fluoride route for the synthesi...
Zeolites are microporous crystalline materials with highly regular framework structures consisting of molecularsized pores and channels. The characteristic framework type of a zeolite is conventionally defined by combining information on its coordination sequences, vertex symbols, tiling, and transitivity information. Here we present a novel knowledge-based approach for zeolite framework type c...
The electroactivity of zeolite-encapsulated redox-active transition metal complexes, {M(L)}Z, was explored for Co(salen) and [Fe(bpy)3] formed in NaY zeolite (where salen ) N,N′-bis(salicylidene)ethylenediamine and bpy ) 2,2′-bipyridine). The zeolite boundary was characterized via X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry in nonaqueous electrolyte at either zeolite-modified ...
Ammonia occurs in marine waters including effluents, receiving waters, and sediment interstitial waters. At sufficiently high concentrations, ammonia can be toxic to aquatic species. Toxicity identification evaluation (TIE) methods provide researchers with tools for identifying aquatic toxicants. For identifying ammonia toxicity, there are several possible methods including pH alteration and vo...
Over the years, many strategies have been developed to address the problem of sintering of nanoparticle catalysts, including encapsulating metal nanoparticles in protective shells, and trapping nanoparticles in the cavities of certain zeolites in post-synthesis steps. In general, materials that contain metal nanoparticles that are only accessible via zeolite micropores are intriguing, specifica...
Hydrothermally synthesized high silica borosilicates with the MFI structure was subjected to several characterization techniques. The effect of boron on the structure and acidity of HZSM-5 catalyst were studied by XRD, SEM, N2 adsorption, solid state NMR, NH3-TPD. It was confirmed that boron had entered the framework in the boron samples. The results also revealed that strong acidity was weaken...
Understanding the behavior and dynamic structural transformation of subnanometric metal species under reaction conditions will be helpful for understanding catalytic phenomena and for developing more efficient and stable catalysts based on single atoms and clusters. In this work, the evolution and stabilization of subnanometric Pt species confined in MCM-22 zeolite has been studied by in situ t...
Converting syngas into ethanol (EtOH) is highly attractive but remains challenge. Dimethyl ether (DME) carbonylation with CO to methyl acetate (MA) on zeolite and its further hydrogenation EtOH Cu-based catalyst open a new synthesis route from syngas. In this work, nano-sized ZSM-35 (NZ35) zeolite, possessing abundant active sites porosity short diffusion path, found realize much better activit...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید