Study the Effect of Seeding Suspension Concentration of DD3R Particles on the Modified Surface of Α-Alumina Support for Preparing DD3R Zeolite Membrane with High Quality

Abstract

In this study, seeding of DD3R particles as an important step in the synthesis of DD3R membrane with secondary growth method was investigated. Dip-coating method is used for seeding of DD3R particles on the modified surface of α-alumina supports. 0.1, 0.2 and 0.3 wt% aqueous suspensions of the DD3R seeds were prepared and each support was coated three times with dipping time of 240 s. Scanning electron microscopy (SEM) analysis was used for the investigation of the quality of seed layer formed on the support. It is shown that the uniform layer of seeds was formed with 0.2 wt% seed suspension concentration. DD3R zeolite membrane was synthesized via hydrothermal method on the support seeded with 0.2 wt% seed suspension concentration. The X-ray diffraction and SEM analysis confirmed the synthesis of uniform DD3R zeolite membrane layer on the support which can be due to the uniform distribution of the DD3R seeds. Single gas permeation tests of N2, CO2 and CH4 were carried out, so that good perm-selectivity for gas mixtures was observed.

Effect of surface roughness and hardness of leadframe on the bondability of gold wedge bonds

“…In addition, leadframe A has higher standard deviation value of 33.8 compared to that of leadframe B with 6.3 of standard deviation. This is because of fact that leadframe A has higher variation of peaks and valleys compared to that of leadframe B, because R a is directly proportionate with hardness standard deviation value (Kim and Au, 2001;Meshkat et al, 2018;Zulu and Mukendi, 2018). Figures 6 and 7 show the ultrasonic vibration waveform in vertical axis amplitude and resonance frequency obtained from laser interferometer for leadframes A and B, respectively.…”

A Sensing System for Continuous Monitoring of Bread Dough During Fermentation

“…Results of studies that have compared gas production and volume expansion in fermenting dough indicate that gas release takes place slowly for 1-2 h from the start of fermentation and then accelerates rapidly [32]. The initial slow release can be explained by the phenomenon of gas emission and evaporation; in this case dough surface behaves like a uniform thin membrane layer with high permeability [35]. The initial slow release can be explained by the phenomenon of gas emission and evaporation; the rapid increase in gas release can occur due to external crust disruption.…”