Scanning electron microscopy mixture analysis

Wortmann F J, Quantitative fiber mixture analysis by scanning electron microscopy. Part III Round trial results on mohair/wool blends , Textile Research Journal, 1991,61, 371-374. 

The syntheses of the ZSM-5 zeolites were based on two different patents (refs. 2-3). In two of the synthesis mixtures sodium ions were, however, largely replaced by potassium ions (table 1). Protonation was achieved by ion-exchange with an aqueous 1 M solution of ammonium-nitrate followed by calcination for 8 hours at 500 °C. In addition, one H-ZSM-5 catalyst was kindly supplied from MOBIL. The zeolites were characterized by x-ray diffraction, scanning electron microscopy, pore-volume measurements (BET) and elemental analysis (ICP). Catalytic experiments were performed at atmospheric pressure by feeding methanol diluted with nitrogen (1 5) into a continuous flow quartz microreactor containing 25-300 mg H-ZSM-5. The reaction temperature was varied from 245 to 400 °C and the products were analyzed by gas-chromatography. 

A zeolite with MFI structure was synthesised with 3 different amounts of niobium ammonium complex (NAC) in the reaction mixture. The samples obtained were characterised by scanning electron microscopy (SEM) using secondary electron detector and energy dispersive spectrum (EDS) detector, X-ray diffraction (XRD), differential thermal analysis (DTA), and electron paramagnetic resonance (EPR). The increase of NAC in the reaction mixture results in the decrease of the crystal size of the zeolite. The characterisation shows evidence that the niobium was incorporated into MFI structure. 

The purpose of this chapter is to present the LAD performance experiments carried out in room temperature liquids. Bubble point and reseal pressure tests for a 325x2300, 450 X 2750, and 510 x 3600 Dutch Twill screen are conducted in storable liquids, methanol, acetone, IPA, water, and binary methanol/water mixtures of various methanol concentrations. First screen pore diameters are estimated based on analysis from scanning electron microscopy and historical data. Experimental results are used to compare methods for determining effective pore diameter. Next, contact angles are measured for both pure and binary mixture fluids using a modified version of the Sessile Drop technique. Then, the equation of state analysis from Neumann and Good (1979) is used to determine the critical Zisman surface tension for stainless steel LAD screens, which... 

X-ray diffraction analysis was performed on the zinc sulfide films as deposited on the substrates. The diffraction patterns showed that the films consisted of ZnS crystallized as a mixture of cubic and hexagonal phases. Scanning electron microscopy studies showed a submicrometer grain texture with the size of most particles being about 0.3 pm. The measured direct optical gap was found to be 3.65 eV. 

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