Some Comments

Prom the view point that a plateau modulus Gjv can only be clearly measured in a nearly monodisperse high-molecular-weight sample, the number of entanglement strands per cubed entanglement distance nt, which 

When Fetters et al. reported the voluminous data covering a wide range of Gjv (Tables 13.1 and 13.2), they offered another interpretation for nt as a universal constant. They started with the idea that the larger the dimension of a chain coil, the greater the volmne it sweeps out, and the greater the number of other chains it wiU encoimter with which it might entangle. They defined the volume pervaded by the chain as 

they defined Mg (which they also linked with the plateau modulus Gjv according to Eq. (13.2) as described below) as the molecular weight of a chain at which Ngp = 2, that is, when there is just one other chain in the sparmed volume. Since Vsp is proportional to a at M = Mg, the argument naturally leads to an equation equivalent to Elq. (13.4), disregarding the difference in the proportional constant. The arbitrariness of setting Ngp = 2 at M = Mg is absorbed in the proportional constant as well. Fetters et al. started by setting Ngp equal to 2 at the onset of entanglement, which they assumed to be Mg, and then they moved on to link this Mg with the plateau 

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Rice S A 1975 Some comments on the dynamics of primary photochemical processes Excited States ed E C Urn (New York Academic) pp 111-320... 

A survey of available methods has, among others, been given by Smith and Van Gunsteren [51] see also Gilson [63]. Here a short overview of methods, with some comment on their quality and properties, will be given. 

In spite of these obstacles, crystallization does occur and the rate at which it develops can be measured. The following derivation will illustrate how the rates of nucleation and growth combine to give the net rate of crystallization. The theory we shall develop assumes a specific picture of the crystallization process. The assumptions of the model and some comments on their applicability follow ... 

D. P. Gowing, "Some Comments on Growth Regulators with a Potential in Agriculture," in Ref. 27. 

Kamlet, M.J. and Adolph, H.G., Some Comments Regarding the Sensitivities, Thermal Stabilities, and Explosive Performance Characteristics of Fluorodi-nitromethyl Compounds, in Seventh Symposium (International) on Detonation, NSWC MP 82-334 (edited by Short, J.M.), Naval Surface Weapons Center, White Oak, Silver Spring, MD, 1982, pp. 84-92. 

Industry is far from understanding the true capabiiity of their designs. Some comments from senior managers and engineers in the industry give an indication of the cuiturai probiems faced and the education needed to improve design processes in this respect. 

Some comments on the design of PFC circuits. First, the EMI filter is an integral part of any PFC eireuit. It filters out the switehing harmonies from the input eurrent waveform. Without an EMI filter, your produet will fail the EMI/RFI tests whieh are in addition to the power faetor tests. Please refer to Appendix E for information on how to design an EMI filter. Seeondly, using a variae during the measurements will affeet the input line impedanee and thus affeets... 

Some stereospecific reactions are listed in Scheme 2.9. Examples of stereoselective reactions are presented in Scheme 2.10. As can be seen in Scheme 2.9, the starting materials in these stereospecific processes are stereoisomeric pairs, and the products are stereoisomeric with respect to each other. Each reaction proceeds to give a single stereoisomer without contamination by the alternative stereoisomer. The stereochemical relationships between reactants and products are determined by the reaction mechanism. Detailed discussion of the mechanisms of these reactions will be deferred until later chapters, but some comments can be made here to illustrate the concept of stereospecificity. 

Polymerization inhibitors are key additives which prevent premature gelation of the adhesive. The foimulator must carefully balance shelf stability and the required cure on demand. Due to its high propagation rate, MMA is difficult to inhibit. Some comments on specific inhibitors follow. The most common inhibitor to be found in component monomers is 4-methoxyphenol, which is also called the methyl ether of hydroquinone. This inhibitor is effective only in the presence of oxygen. A mechanism has been proposed, and is illustrated in Scheme 13 [128]. 

WASH-1400 (FINAL), Appendix XI presents comments and responses on the draft repiirt. Some of these resulted in changes that were incorporated in the final report. Only a few critiques of the final report have been published. Two of these are NUREG/CR-0400 (Lewis Report) and Kendall, 1977. Of these, the Lewis Report s comments are the most objective (Leverenz and Erdmann, 1979, provide a review of the Lewis review). Some comments are summarized ... 

There are, however, some crown type compounds which contain no structural feature except the thiophene subunit, and these deserve some comment here. This is especially true since one of these compounds was prepared very early in the history of crown compounds. Ahmed and Meth-Cohn were interested in sulfur analogs of the porphyrin ring system and prepared compound 7 in 1969 by the method shown in Eq. 

R. W. Moollan, B. Rae and A. Verbeek, Some comments on the detennination of microcystin toxins in water by liigh perfonnance liquid cliromatography. Analyst 121 233-238(1996). 

It was recommended in Section 1.4 that hydrogenation catalysts be bought rather than made. Nonetheless, for those who wish to make their own catalyst some comments seem in order. 

P.-0. Lowdin, Some Comments on the Periodic System of the Elements, International Journal of Quantum Chemistry, (Symposium) 11 IS, 331-334, 1969. 

Lowdin, P-O. 1969. Some comments on the periodic system of elements. International Journal of Quantum Chemistry. Symposium 3 331-334. 

Barrer s discussion4 of his analog of Eq. 28 merits some comment. Equation 28 expresses the equilibrium condition between ice and hydrate. As such it is valid for all equilibria in which the two phases coexist and not only for univariant equilibria corresponding with a P—7" line in the phase diagram. (It holds, for instance, in the entire ice-hydratell-gas region of the ternary system water-methane-propane considered in Section III.C.(2).) In addition to Eq. 28 one has Clapeyron s equation... 

Among the various agents which provoke the resinification of 2-furaldehyde, ultraviolet light has been the least studied. Some comments have already been made on... 

It is appropriate to add here some comments on diazotization in anhydrous carboxylic acids. They may be relevant for the diazotization of heteroaromatic amines carried out in acetic acid/propionic acid mixtures (Sec. 2.2). Extensive studies by Casado et al. (1983, 1984) showed that in nitrosation of secondary amines the nitrosyl ion, nitrosyl acetate, and dinitrogen trioxide are formed, and all three may act as nitrosating agents. The results do not, however, account for the considerable improvement that is claimed in the patent literature (Weaver and Shuttleworth, 1982) to result from the addition of carboxylic acids in the diazotization of heteroaromatic amines. 

This account of the kinetics of reactions between (inorganic) solids commences with a consideration of the reactant mixture (Sect. 1), since composition, particle sizes, method of mixing and other pretreatments exert important influences on rate characteristics. Some comments on experimental methods are included here. Section 2 is concerned with reaction mechanisms formulated to account for observed behaviour, including references to rate processes which involve diffusion across a barrier layer. This section also includes a consideration of the application of mechanistic criteria to the classification of the kinetic characteristics of solid-solid reactions. Section 3 surveys rate processes identified as the decomposition of a solid catalyzed by a solid. Section 4 reviews other types of solid + solid reactions, which may be conveniently subdivided further into the classes... 

Some comments are worth mentioning with regard to determination of the molecular weight of celluloses dissolved in these solvent systems ... 

Friis and Hamielec (48) offered some comments on the continuous reactor design problem suggesting that the dispersed particles have the same residence time distribution as the dispersing fluid and the system can be modeled as a segregated CSTR reactor. 

Chivas, A.R. 1984 Some comments and further recommendations on a report by O Donnell and Waugh concerning an explosion involving bromine pentafluoride at the Geology Department, University of Queensland. Adelaide The Australian National University Memorandum. 

Two features require some comment. The induction of depolarisation block in DA neurons needs afferent input to the nuclei, since prior lesion of the striatum and nucleus... 

The results presented in Tables 3 and 4 deserve some comments. First, a variety of enzymes, including whole-cell preparations, proved suitable for the resolution of different hydroxyalkanephosphorus compounds, giving both unreacted substrates and the products of the enzymatic transformation in good yields and, in some cases, even with full stereoselectivity. Application of both methodologies, acylation of hydroxy substrates rac-41 and rac-43 or the reverse (hydrolysis of the acylated substrates rac-42 and rac-44), enables one to obtain each desired enantiomer of the product. This turned out to be particularly important in those cases when a chemical transformation OH OAc or reverse was difficult to perform. As an example, our work is shown in Scheme 3. In this case, chemical hydrolysis of the acetyl derivative 46 proved difficult due to some side reactions and therefore an enzymatic hydrolysis, using the same enzyme as that in the acylation reaction, was applied. Not only did this provide access to the desired hydroxy derivative 45 but it also allowed to improve its enantiomeric excess. In this way. 

Thus, in accordance with Equation (1.1) the mass Am(p) is subjected to the force dF(p) which is directly proportional to the product of both masses and inversely proportional to the square of the distance between them, and it has a direction opposite to hgp, (the presence of minus at the right hand side of Equation (1.1) illustrates this fact). This extremely simple formula describing the basic physical law of the gravimetry may need some comments. 

D. J. Greenland, The physics and chemistry of the. soil-root interface some comments. The Soil-Root Interface (J. L. Harley and J. S. Russell, eds.) Academic Press, London, 1979, p. 83. 

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