Bond strength index

This method derives from the observation that the degree of enrichment in a set of cogenetic silicate minerals (expressed as oxygen isotope index I- 0) can be related to bond strengths in minerals (Taylor, 1968). The oxygen isotope index for phase A is defined by... 

IB = internal bond strength F = suffix used to indicate methylolated sample WtpF = weight of PF resin in a lOOg board WtML = weight of methylolated lignin in a lOOg board Rf = total aliphatic OH index Ra = total alcohol index... 

The minute quantity of adsorbate remaining on the column after weakly bound probe has desorbed is chemisorbed to strongly acidic or basic sites on the substrate. The desorption profile obtained by ramping the column temperature is an index of the range of effective bond strength between the solid and adsorbed vapor. The flame ionization detector also registers desorption of adventitious organic contaminants polytherms with no probe on the column must be obtained separately so that sorbate and contaminant desorption can be deconvolved. 

Bond order the difference between the number of bonding electrons and the number of antibonding electrons, divided by two. It is an index of bond strength. (14.2)... 

Figure 7.24. A. Relationship between 8 so values and the summed bond strengths of the oxygen atoms for a number of phosphates. Opien symbols denote orthophosphates, closed symbols denote higher phosphates. From Cheetham et al. (1986), by permission of the Royal Society of Chemistry. B. Relationship between the CSA for several orthophosphates and the geometrical distortion index (DI) of the phosphate group. From data of Turner et al. (1986a).

Koretsky et al. calculated site densities for particular low index faces of six oxides and six silicate minerals and average site densities for cleavage and growth faces, and showed that these methods lead to very different results. Full documentation of depth, length of broken bond and Brown bond strengths of broken bonds for particular types of sites is presented. The ranges of TVs calculated by Koretsky et al. [7] and in their literature data collection (tritium exchange, acid-base titrations, NMR, adsorption and desorption of water at various conditions, and saturation experiments with different adsorbates in solution) for six oxides are listed in Table 5.1. 

When the HOMA index calculated for the phenol rings is plotted against the C-O bond length (an approximate measure of H-bonding strength) for 664 H-bonded phenol derivatives retrieved from the Cambridge Structure Database, the dependence looks as in Fig. 10 [36]. 

Long-term behavior of insulation systems can be estimated after the temperature index has been determined by the impregnated twisted pair test (IEC 172, criterion breakdown voltage) or helical coil test (IEC 1033, Method B, criterion bond strength). The two tests lead to differing results that do not correlate and the end user of the system enameled wire/impregnating resin has to decide which test is applicable for his electrical appliance. It is important to choose a suitable combination of materials and to ensure close cooperation between manufacturers of electrical insulating materials and those who later process them. 

Product Name/Supplier Type Viscosity (cP) Thixo- tropic Index Shelf Life (-40°C)/Pot Life (25 °C) Cure Schedule % Wt Loss 300°C (TGA) Bond Strength (psi) MOE (MPa/psi) CTE (ppm/ Tg °C) (°C) Volume Resistivil (ohm-cm) Thermal Ionic Conducdvily Impurities (WAnK) (ppm) ... 

Note-. As5mimetric index of the bands correspond to the stretching vibration of OH groups, MHBS is the mean hydrogen bond strength, and Cr.l. is the crystallinity index CAi43o/A90o1-... 

Silvi and coworkers have explored the potential of the electron locahzation function (ELF) approach for the characterization of H bonds [71]. They discussed how ELF-derived quantities behave when a H bond exists. Fuster and Grabowski compared QTAIM and ELF as descriptors of H bonds. They found good correlations between ELF and QTAIM parameters, and demonstrated that many of their parameters, especially the core-valence bifurcation index and the total electron energy density at the HBCP, are particularly useful in describing the H-bond strength [72]. 

Figure 13.17 shows the indexed values of burst strength as a function of NSE at various levels of refining intensity. Similar plots for internal bond-strength values are shown in... 

Product Name/ Supplier Type Viscosity cps Thixo- tropic Index Shelf Life ( 0°C)/ Pot Life (25°C) Cure Schedule %wt Loss 300°C (TGA) Bond Strength psi MOE MPa psi CTE ppm/°C T, °C Volume Resistivity ohm-cm Thermal Conduc- tivity W/mK Ionic Impur- ities ppm... 

---