ETSI

The NMR chemical shifts of the polymers 10 and 11 are only slightly dependent on the molecular weight. The NMR spectrum of the polymer 10 shows three shrap resonances at 6 0.34, 0.94, and 7.28 ppm, due to MeSi, EtSi, and phenylene ring protons, while the polymer 11 reveals shrap resonances at 6 0.62, 7.28, and 7.35 ppm, attributed to MeSi and phenyl ring protons. The polymers 10 and 11 show characteristic strong absorption bands at 262 and 254 nm, respectively, significantly red-shifted relative to pentamethylphenyl-disilane which exhibits an absorption band at 231 nm. 

Fig. 9. Structure of [EtSi PNa(SiPii) 3]2 (toluene)2. Reproduced with permission from M. Driess et al., Angew. Chem. Int. Ed. Engl. 1995, 34, 316. Copyright 1995, Wiley-VCH.

Polyhedral Oligosilsesquioxanes and Their Homo Derivatives Et(BuO) SiClj ----------Et(BuO)2SiCI ------------- EtSi(0Bu)3... 

Silylene intermediates have also been proposed for the reaction of alcohols with silicon357. When phenol is reacted with silicon in the presence of CuCl as a catalyst, the major product (PhO)3SiH is obtained in 94% selectivity. This result is explained by insertion of a silylene Si(OPh)2 into the O—H bond of phenol. Addition of ethylene to the reaction produces 5.8% of EtSi(H)(OPh)2, which can be accounted for by the reactions of Scheme 14358. 

Similarly, reaction of silicon, methanol and ethylene in an autoclave at 433 K produces ethylmethoxysilanes, EtSi(H)(OMe)2 and EtSi(OMe)3, as well as HSi(OMe)3 and Si(OMe)4. And, although 2-propanol does not react with silicon, a mixture of methanol and 2-propanol reacted with silicon to yield i-PrOSi(H)(OMe)2359. Taken together, these results strongly suggest the intermediacy of silylene-like species in these reactions. 

Figure 1.12 The same as Fig. 1.11 but for the ETSI GSM half rate speech database.

Figure 1.16 Relation between the MOS and the cognitive corrected PAQM (PAQMc4.o, wo.i) for the ETSI GSM full rate speech database. Crosses represent data from the experiment based on the modulated noise reference unit, circles represent data from the speech codecs.

Relation between MOS and PAQM, ETSI GSM full rate database 23... 

Relation between MOS and PAQMc, ETSI GSM half rate database 31... 

ETSI91tm74, 1991] ETSI91tm74 (October 1991). Global analysis of selection tests Basic data. ETSI/f M/f M5/ICI I-I IS. Technical Document 91/74. 

ETSIstdR06, 1992] ETSIstdR06 (1992). Speech codec specifications. ETSI/GSM. ETS R.06. 

Widely adopted technical standards for this area are also still missing. A format for Archival Electronic Signature (ES-A) has been defined in [ETSI]. An IETF working group is working in this field (see [DOS] and [WAL]), but most documents are at the level of Internet Drafts and they are works in progress. 

ETSI] ETSI TS 101 733 V 1.5.1 (2003-12) Electronic Signatures and Infrastructures (ESI) Electronic Signature Formats, http //www.ictsb.org/EESSI home.htm... 

Raton, Florida, 1995 Theodore and Allen, Air Pollution Control Equipment, ETSI Prof. Training Inst., Roanoke, Virginia, 1993. 

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