Brunauer - Emmett -Teller BET surface area

The N2 adsorption-desorption isotherms for MSU-Ge-2 show a type-lV adsorption branch associated with a well-defined capillary condensation step at P/Po 0.13, characteristic of uniform mesopores (Fig. 4). The adsorption data indicate a very high Brunauer-Emmett-Teller (BET) surface area of 363 m /g and a pore volume of 0.23 cm /g. Given that the Ge mesostructure is much heavier than the corresponding silica, this surface area is actually equivalent to silica with a surface area of 1,316 m /g. 

Transmission and scanning electron microscopy are employed for a direct study of microclusters while the distribution of sizes (or average diameter) is provided by sedimentation and other techniques. The average particle diameter is obtained by the Brunauer-Emmett-Teller (BET) surface-area method and by X-ray line broadening. 

The data reported by Basila et al. (221,224) lead to a value of 1.6 03. Using the apparent integrated absorption intensities as given by Hughes and White (198), Ward and Hansford (226) estimated the limits of detection of Br nsted acidity to be of the order of magnitude of 10 2 meq g-1 for silica-aluminas with Brunauer-Emmett-Teller (BET) surface areas between 350 and 500 m2 /g. 

Brunauer-Emmett-Teller (BET) surface area = 222 g" , single-point total pore... 

There are three different gas adsorption methods usually employed to obtain surface fractal dimension. In the first method, the particles are fractionated into narrow particle size distribution and the Brunauer-Emmett-Teller (BET) surface area is measured for each size fraction. Ds can then be determined from Eq. (7) ... 

By definition, the intrinsically high surface area of gels requires that gases are accessible to a substantial portion of the solid phase. For example, in a gel with a Brunauer-Emmett-Teller (BET) surface area of 850 m2/g, 65% of the silicon atoms are on a surface. The accessibility of the surface makes gas- or liquid-phase reactions a viable means of bulk compositional modification. This situation has been exploited by numerous researchers who have reacted silicate xerogels with ammonia to form oxynitride glasses without melting (105-107). 

The first two forms of degradation can be suppressed by forming solid solutions of catalysts with certain isostructural compounds which possess high Brunauer-Emmett-Teller (BET) surface areas of superior thermal stability. However, these studies demonstrate that transition metal oxide solid solutions are doubtful candidates for use as automotive catalysts for a variety of reasons. 

An excess amount of lithium (1.02 mol) was used to compensate for the loss of lithium during firing. The resultant powders showed a Brunauer-Emmett-Teller (BET) surface area of 1 mVg. The process for AlPO coating on the cathode is identical to the LiCoO described above. 

Despite the small pore diameters of the xerogels, their Brunauer-Emmett-Teller (BET) surface areas are still quite high, at 50% of those of the corresponding native samples. On the other hand, despite their minimal shrinkage relative to the molds. 

Due to the inefficient packing of the rigid struts, CMPs have an open structure even after removal of all solvents. This open structure leads to high surface areas and pore volumes. Surface areas of CMPs are most often reported as Brunauer-Emmett-Teller (BET) surface areas, which takes into account the adsorption of multiple adsorbate layers. 

Various Brunauer-Emmett-Teller (BET) surface areas have been obtained for hyper-crosslinked networks of polypyrrole using diiodomethane, triiodo-methane and triiodoborane by erosslinking with CH2, CH and B erosslinkers, respectively. It was also observed that HCPs reduced with metal partieles like Li possess inereased selectivity towards CO2 over CH4, although there was a decrease in surface area as metal partieles fill the pores (not post-synthesis). 

Iodine adsorption it is a simple and quick test, giving an indication of the internal surface area of the carbon in many activated carbons the iodine number (expressed as milligrams of iodine per gram of carbon) is close to the Brunauer-Emmett-Teller (BET) surface area. In this method, the activated carbon is boiled with 5% HCl and, after cooling, a 0.1N iodine solution is added and shaken for 30 s after filtration, the filtrate is titrated with O.IN sodium thiosulfate solution, with starch as indicator. The standard used is AWWA B600-78 (see Section 8.1.2). 

Generally, the experimental Brunauer-Emmett-Teller (BET) surface areas of SWCNTs reported in literature range from 300 to 800 m /g, depending on the experimental parameters chosen for the measurements, on the CNTs studied, and on the treatments (purification, activation processes, etc.) applied to these CNTs." ... 

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