Systems demonstrations

The first mass spectrometric investigation of the thiazole ring was done by Clarke et al. (271). Shortly after, Cooks et al., in a study devoted to bicydic aromatic systems, demonstrated the influence of the benzo ring in benzothiazole (272). Since this time, many studies have been devoted to the influence of various types of substitution upon fragmentation schemes and rearrangements, in the case of alkylthiazoles by Buttery (273) arylthiazoles by Aune et al. (276), Rix et al. (277), Khnulnitskii et al. (278) functional derivatives by Salmona el al. (279) and Entenmann (280) and thiazoles isotopically labeled with deuterium and C by Bojesen et al. (113). More recently, Witzhum et al. have detected the presence of simple derivatives of thiazole in food aromas by mass spectrometry (281). 

The flow of a current through an electrochemical system demonstrates the main difference between material based on conducting polymers and all the other industrial nonconducting polymers conducting polymers oxidize and reduce electrochemically in a reverse way, as do metals or redox couples ... 

The Lick AO system demonstrated the first wavefront correction using a Na LGS (Max et al., 1997), and engineering tests demonstrated LGS corrected Strehls of 0.5-0.6 at 2.2 m (Fig. 15, Gavel et al., 2003). In 2002, the LGS system was turned over to the Observatory staff for operation in science observing mode. It is used almost 100 nights per year. The first refereed science paper using a sodium LGS/AO system was published by Perrin et al. (2004). 

Methods of detection, metabolism, and pathophysiology of the brevetoxins, PbTx-2 and PbTx-3, are summarized. Infrared spectroscopy and innovative chromatographic techniques were examined as methods for detection and structural analysis. Toxicokinetic and metabolic studies for in vivo and in vitro systems demonstrated hepatic metabolism and biliary excretion. An in vivo model of brevetoxin intoxication was developed in conscious tethered rats. Intravenous administration of toxin resulted in a precipitous decrease in body temperature and respiratory rate, as well as signs suggesting central nervous system involvement. A polyclonal antiserum against the brevetoxin polyether backbone was prepared a radioimmunoassay was developed with a sub-nanogram detection limit. This antiserum, when administered prophylactically, protected rats against the toxic effects of brevetoxin. 

More recently, Henry et al. (2002) have applied this same profile approach to dorrble-crested cormorants, snowy egrets, and black-crowned night herons from the Carson River system, demonstrating its across-species applicability. Hermy and coworkers expanded the profile to include histopathological parameters. 

Copp and Everet (1953) have presented 33 experimental VLE data points at three temperatures. The diethylamine-water system demonstrates the problem that may arise when using the simplified constrained least squares estimation due to inadequate number of data. In such case there is a need to interpolate the data points and to perform the minimization subject to constraint of Equation 14.28 instead of Equation 14.26 (Englezos and Kalogerakis, 1993). First, unconstrained LS estimation was performed by using the objective function defined by Equation 14.23. The parameter values together with their standard deviations that were obtained are shown in Table 14.5. The covariances are also given in the table. The other parameter values are zero. 

Microbiological aspects will need to be discussed, but the amount of information will depend on the type of product. For nonsterile products there will need to be a description of the microbiological attributes of the product and, if appropriate, a rationale for not performing microbial limit tests. For preserved products the selection of the antimicrobial preservatives will need to be discussed and the effectiveness of the selected system demonstrated. For sterile products there will need to be appropriate process validation data and information on the integrity of the container-closure system. 

PAMPA 50+ MODEL LIPID SYSTEMS DEMONSTRATED WITH 32 STRUCTURALLY UNRELATED DRUG MOLECULES... 

There has been particular recent interest in zinc nitrate complexes as coordination models for bicarbonate binding in carbonic anhydrase. The mono- or bidentate coordination modes have been studied with tris-pyrazolyl borate complexes and can be rationalized in the context of the enzyme activity.433 Caution in this comparison is introduced by ab initio calculations on these model systems demonstrating both monodentate and bidentate coordination energy minima for nitrate binding to zinc 434... 

Amide 39 is a potent and selective inhibitor of GlyT-1 both in vitro (Ki = 1.79 nM) and in vivo (CSF-glycine ED2oo 3.9 mg/kg, rat, p.o.) but with limited permeability across Madin-Darby canine kidney (MDCK) cell membranes [78]. Optimization led to fused [3.1.0] and [3.3.0] azabi-cyclic analogs 40 (PF-3463275) [78] and 41 [79], respectively. Analogs of both systems demonstrated excellent potency (fC = 1.7-95 nM), and improved permeability, PK, and in vivo efficacy. Spatial working memory... 

Effect of Concentration and CO Pressures on the Ruthenium Carbonyl-Trimethylamine WGSR System. As shown in Figure 1, the RU3(CO) 2/NMe3 WGSR system demonstrates a nearly first-order rate dependence on CO pressure at 0.5 mM Ru3(CO) 2 concentration. (Throughout this discussion, the total ruthenium carbonyl concentration is expressed as moles Ru3(00) 2 added per liter of solution this should not be construed to be the actual solution concentration of the trimer under operating conditions.) Here the initial rates of H2 production are 14.6 mmol /hr at 415 psi CO and 46.0 mmol /hr at 1200 psi. Thus, within experimental uncertainty, a threefold increase in CO pressure leads to a threefold increase in rate. 

Both systems demonstrate unrevealed failures. For the alarm system the failure rate is /t = 0.18 faults/yr. The inspection period is 1/12 = 0.083 yr. The unavailability is computed using Equation 11-25 ... 

The electrosynthesis of metalloporphyrins which contain a metal-carbon a-bond is reviewed in this paper. The electron transfer mechanisms of a-bonded rhodium, cobalt, germanium, and silicon porphyrin complexes were also determined on the basis of voltammetric measurements and controlled-potential electrooxidation/reduction. The four described electrochemical systems demonstrate the versatility and selectivity of electrochemical methods for the synthesis and characterization of metal-carbon o-bonded metalloporphyrins. The reactions between rhodium and cobalt metalloporphyrins and the commonly used CH2CI2 is also discussed. 

In summary, the four chemical systems described in this paper demonstrate the versatility and selectivity of electrochemical methods for synthesis and characterization of metal-carbon a-bonded metalloporphyrins. The described rhodium and cobalt systems demonstrate significant differences with respect to their formation, stability and to some extend, reactivity of the low valent species. On the other hand, properties of the electroche-mically generated mono-alkyl or mono-aryl germanium and silicon systems are similar to each other. 

A striking feature of disperse dye development in recent decades has been the steady growth in bathochromic azo blue dyes to replace the tinctorially weaker and more costly anthraquinone blues. One approach is represented by heavily nuclei-substituted derivatives of N,N-disubstituted 4-aminoazobenzenes, in which electron donor groups (e.g. 2-acylamino-5-alkoxy) are introduced into the aniline coupler residue and acceptor groups (acetyl, cyano or nitro) into the 2,4,6-positions of the diazo component. A PPP-MO study of the mobility of substituent configurations in such systems demonstrated that coplanarity of the two aryl rings could only be maintained if at least one of the 2,6-substituents was cyano. Thus much commercial research effort was directed towards these more bathochromic o-cyano-substituted dyes. 

High transparency makes P.Y.24 a valuable pigment for metallic finishes. It is used in relatively light shades, typically at a ratio of one part of color pigment to three parts of aluminum pigment. Thus prepared systems demonstrate excellent weatherfastness. Flavanthrone Yellow, like P.Y.108, tends to seed (Sec. 3.7.3.1). The pigment is heat stable up to 200°C and thus satisfies all possible heat stability requirements in this area. Flavanthrone Yellow is used in various industrial paints, especially in automobile O.E.M. finishes and in automotive refinishes. 

The influence of steric effects on the rates of oxidative addition to Rh(I) and migratory CO insertion on Rh(III) was probed in a study of the reactivity of a series of [Rh(CO)(a-diimine)I] complexes with Mel (Scheme 9) [46]. For a-diimine ligands of low steric bulk (e.g. bpy, L1, L4, L5) fast oxidative addition of Mel was observed (103-104 times faster than [Rh(CO)2l2] ) and stable Rh(III) methyl complexes resulted. For more bulky a-diimine ligands (e.g. L2, L3, L6) containing ortho-alkyl groups on the N-aryl substituents, oxidative addition is inhibited but methyl migration is promoted, leading to Rh(III) acetyl products. The results obtained from this model system demonstrate that steric effects can be used to tune the relative rates of two key steps in the carbonylation cycle. 

There are many solid state lasers. One of the most commonly treated types in laser textbooks is the ruby laser (Al203 Cr +), which was the first laser system demonstrated by T. H. Maiman at the Hughes Research Laboratory early in 1960 (Maiman, 1960). Figure 6.9 in Chapter 6 will show the quantum energy levels associated with the unfilled 3d inner shell of the Cr + ion when it substitutes for the AP+ ion in the AI2O3 lattice crystal. By using a ruby rod placed inside a spiral flashlamp filled with a hundreds of torrs of xenon, it is possible to optically pump Cr + ions from the " A2g ground state into the broad " T2 and " Ti bands of the excited levels. After a rapid relaxation down to the very sharp Eg level, laser emission can be produced at 694 nm via the Eg " A2g transition. 

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