The Lewis structure of SiO2 is identical to the Lewis structure of CO2. The only difference is that instead of carbon, silicon is used. One silicon atom is at the middle, with two oxygen atoms bound to it in a double bond. There are no lone pairs on the central atom of the SiO2 Lew...
What is the molecular geometry of SiOH2? Draw its Lewis structure and determine its bond angles. A molecule with the formula AB_3 has a trigonal planar geometry. How many electron groups are on the central atom? How many electrons are involved when t...
The initial Ga/SiO2and Zn/SiO2pre-catalyst was synthesized following previously reported methods22,23, and the structure was determined by in situ X-ray absorption spectroscopy (XAS), including both XANES and EXAFS (Supplementary Table1) and compared to that of Ni/SiO2. The catalysts were dehydr...
field emission scanning electron microscopy (FESEM), vibrating sample magnetometer (VSM) analysis, X-ray powder diffraction (XRD) technique, energy-dispersive X-ray spectroscopy (EDX), and thermogravimetric analysis (TGA) were used to characterize the structure of core–shell...
Based on the integrated absorbance of Lewis/Brønsted acid bands and molecular absorption coefficients [73], the concentrations of Lewis and Brønsted acid sites were estimated to be 42.3 and 1.3 μmol/g, respectively. These results indicate that the WO3-20SiO2-0.5 catalyst possesses mainly ...
The final structure is found through geometry optimization. As applied to heterostructures, the result of such modeling depends on the choice of one or another polymorphic modification of SiO2. To choose the most adequate one, it is necessary to go through all possible variants and compare their ...
Two atomization disks with vanes of different geometry were manufactured from 316 stainless steel. The designs consisted of a straight radial rectangular vanes (DAR) disk (Figure A3a) and a curved rectangular vanes (DAC) disk (Figure A3b). The structure of the discs incorporates a hollow circul...
The crystal structure of the Fe3O4 NPs conforms to a cubic system with lattice parameters and d-spacing of 0.29 nm for the miller index of the major peak (311). For the lattice parameter and particle size of Fe3O4 NPs generated at varied temperatures, comparable findings were noticed. It...
Keywords: catalytic adsorbent; NaY zeolite; regeneration; X-ray absorption fine structure; CO-induced Pt aggregation 1. Introduction The effluents from industrial processes often contain VOCs (volatile organic compounds), which pose a threat to human health and the environment [1–3]. For low VOC...