Previous observations

Surface reconstructions have been observed by STM in many systems, and the teclmique has, indeed, been used to confmn the missing row structure in the 1 x 2 reconstruction of Au(l 10) [28]. As the temperature was increased within 10 K of the transition to the disordered 1 1 phase (700 K), a drastic reduction in domain size to -20-40 A (i.e. less than the coherence width of LEED) was observed. In this way, the STM has been used to help explain and extend many observations previously made by diffraction methods. 

Transverse cracks shown in Fig. 10.8 were found in a total of 15 tubes from random areas of the condenser. The equipment had been in continuous service for 2 years. Cracks had not been observed previously. 

Holden et al. [27] reported the first Raman results on nanotubes produced from a Co-catalyzed carbon arc. Thread-like material removed from the chamber was encapsulated in a Pyrex ampoule in -500 Torr of He gas for Raman scattering measurements. Sharp first-order lines were observed at 1566 and 1592 cm and second-order lines al 2681 and 3180 cm , but only when cobalt was present in the core of the anode. These sharp lines had not been observed previously in... 

Tire deprotonation of thiazolium salts (see Section II) under argon at room temperature allowed the characterization of nonfused DTDAF of types 52 and 53 by cyclic voltammetry. Their very good donor properties were confirmed by two quasi-reversible peaks of equal intensity (93CC601). It is noteworthy that upon a second scan the first oxidation peak was shifted from -0.03 to -0.04 V. Upon further scans the voltam-mogram remains unchanged. Tliis interesting feature has been observed previously with TTF analogs. It was demonstrated that the neutral form... 

Anodic oxide formation Lakhiani and Shreir have studied the anodic oxidation of niobium in various electrolytes, and have observed that temperature and current density have a marked effect on the anodising characteristics. The plateau on the voltage/time curve has been shown by electron microscopy to correspond with the crystallisation of the oxide and rupture of the previously formed oxide. It would appear that this is a further example of field recrystallisation —a phenomenon which has been observed previously during anodisation of tantalum" . No significant data on the galvanic behaviour of niobium are available however, its behaviour can be expected to be similar to tantalum. 

Plutonium(IV) polymer has been examined by infrared spectroscopy (26). One of the prominent features in the infrared spectrum of the polymer is an intense band in the OH stretching region at 3400 cm 1. Upon deuteration, this band shifts to 2400 cm 1. However, it could not be positively assigned to OH vibrations in the polymer due to absorption of water by the KBr pellet. In view of the broad band observed in this same region for I, it now seems likely that the bands observed previously for Pu(IV) polymer are actually due to OH in the polymer. Indeed, we have observed a similar shift in the sharp absorption of U(0H)2S0ir upon deuteration (28). This absorption shifts from 3500 cm 1 to 2600 cm 1. 

These findings agree with the trends observed previously for group 15 triorganyls such as EH3, EPhj and EMej (see Table 4, Sect. 2.1.). The decreasing bond angular sums result from decreased steric interactions between the Tms... 

Other cyclizations at phosphorus have been observed when certain phosphinates were used in the acid-catalyzed Mannich reaction. As observed previously with various phosphonous acid derivatives, reaction of aliphatic phosphinic acids with primary amines favored the formation of 2 1 adducts (73). Thus, glycine and other a-amino acids reacted under the typical conditions with excess formaldehyde and alkyl phosphonous acids to give the bis-phosphinylmethyl adducts 125. 

In agreement with observations previously made, recalculated data offer an overall picmre of processing effects along the mixing line. As can be seen, the expected effect of test frequency is observed, except on TR sample, but the most significant observations are made on run 2 data, which... 

The mechanism of the UDMH dark decay is unknown, but it is presumed to be heterogeneous in nature. It is probably not wall adsorption, since much slower decay rates were observed previously in the absence of O2 ( ) ... 

PGE was isolated as desribed in Material and Methods. SDS-PAGE electrophoresis of purified protein showed a single band migrating at approximately 60 kDa. This observation is not in the agreement with the calculated molecular weight of 35 584. However a similar effect has been observed previously in case of PGI and PGC. Apart of the N-glycosylation which plays role in all PGs (Fig. 3), O-glycosylation may also be present as indicated by the band size shift after a treatment of PGE with O.IM NaOH (data not shown). 

As in the 1,2-dichloroethane case too, transient EMF and SHG responses to KSCN were observed for the nitrobenzene membranes without ionic sites. This suggests that here too not only SCN but also K ions are transferred into the nitrobenzene phase. Salt extraction into the bulk of the organic phase, in analogy to similar observations previously reported for neutral ionophore-incorporated liquid membranes without ionic sites [55], was indeed independently confirmed by atomic absorption spectrometry. Figure 15 shows the concentration of K in nitrobenzene equilibrated at room temperature with a 10 M aqueous solution of KSCN as a function of equilibration time. The presence of the ion exchanger TDDMA-SCN efficiently suppresses KSCN extraction into the organic phase but in its absence a substantial amount of KSCN enters the nitrobenzene phase. The trends of the EMF and the SHG responses are therefore very similar in spite of the different polarities of the plasticizers. 

M-H-B interactions have been observed previously for transition metal complexes (see Ref. 2). 

Symmetric bis(unidentate) coordination of bridging carbonate ligands has been observed previously. See ... 

However, the pseudo-borole 95 stemmed from another reaction of 96. Unknown to the earlier researchers who reported the synthesis of 95,94 their attempted preparation of 96 instead gave partly 98, a rearrangement observed previously,95 whereupon the reaction of 98 with PhBCl2 yielded phenyl(bis(2,3,4-triphenyl-l-naphthyl)borane, the actual identity of pseudo-borole 95 (Eq. 31). 

Adjacent subchannels are open to each other through the gap between two neighboring fuel rods flow in one channel mixes with that in the other. In addition, as observed previously, there is crossflow between channels because of the pressure gradient. Local turbulent mixing reduces the enthalpy rise of the hot channel. On the other hand, flow leaving the hot channel increases its enthalpy rise. Calculation of the net result is complicated, although the equation describing enthalpy rise can easily be written. 

We cannot simplify this equation further in particular, we cannot separate out the variances of AEs and AEr, n in order to replace them with the same generic value. To determine the variance of A A/A, that is the relative precision (in chemists terms), we need to evaluate the variance of the two terms in equation 44-77. As we had observed previously, as the value of AEr approaches —Er, the value of the expressions attains infinite values. However, a difference here is that when computing the variance, these values are squared, and hence the computations are always done using positive values. This differs from out previous case, where the presence of both positive and negative values afforded the opportunity for cancellation of near-infinite contributions we do not have that situation here. Therefore we are faced with the possibility that the variance will be infinite. 

All the measurements reported in this paper were carried out at a particle concentration of 1 weight %. Only one concentration was investigated since it has been observed previously (6) that there is little variation in the UCFT as a function of particle concentration in the dilute concentration regime. The dispersion being investigated was added to the pressure bomb which was sealed and -200 bars pressure applied to the system. 

Uniaxial stress results have been reported for several of the IR bands associated with H decorated lattice damage (Bech Nielsen et al., 1989). For these experiments H+ was implanted into Si at room temperature. The resulting spectral features correspond to those observed previously by Stein (1975) and others (see Section III.3). Uniaxial stress splitting patterns were measured for infrared absorption spectra taken at 9 K. The... 

Reaction of 3 with Ph3C+PF6" resulted in the formation of methylidene complex [(n-C5H5)Re(N0)(PPh3)(CH2)]+ PF6 (8) in 88-100% spectroscopic yields, as shown in Figure 11. Although 8 decomposes in solution slowly at -10 °C and rapidly at 25 °C (She decomposition is second order in 8), it can be isolated as an off-white powder (pure by H NMR) when the reaction is worked up at -23 °C. The methylidene H and 13C NMR chemical shifts are similar to those observed previously for carbene complexes [28]. However, the multiplicity of the H NMR spectrum indicates the two methylidene protons to be non-equivalent (Figure 11). Since no coalescence is.observed below the decomposition point of 8, a lower limit of AG >15 kcal/mol can be set for the rotational barrier about the rhenium-methylidene bond. 

Bentazone and MCPA were the most ubiquitous compounds (detected in 100% of the samples), whereas malathion followed by MCPA and molinate were the compounds found at highest concentrations (5,825, 4,197 and 3,590 ng/L, respectively). Pesticide profiles similar to this have been observed previously in the studied area, as... 

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