Critical Comments

Ignoring a permanent competition of intra- and intermolecular condensation steps causes problems for the interpretation of Rory s formulas regardless, if KC or TC polycondensations are concerned. These problems begin with the definition of conversion, p, (Eq. 4.1), because a quantitative conversion (p = 1) cannot be achieved in a perfectly linear polycondensation. For the end of a linear polycondensation a DFmax may be defined which equals the niunber of monomers initially present in the reaction mixture and thus, also equals the number of a groups regardless, if a—b or 02 + monomers are polymerized (Eq. 4.44). 

This definition is also valid for polycondensations of abf monomers. 

Equation 4.1 may be combined with all other equations of Flory when the limitation Nt 2 is added. Without this limitation p — I inserted into the Car-others equation (4.2) has the consequence that DPn goes to infinity. Insertion of p = 1 into the equations of number and mass distributions (4.12) and (4.16) has 

Flory PJ (1953) Principles of Polymer Chemistry. Cornell University Press, Ithaca (ISBN O-8014-0134-8) 

Flory PJ (1969) Statistical mechanics of chain molecules. In Interscience (ISBN 0-470-26495-0), reissued 1989 (ISBN 1-56990-019-1) 

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In Reference 146 three methods for playback of data are presented, which are superior to the usual method based on the contrast in light scattering readout of dichroism, perpendicular readout mode, and readout of birefringence. Some critical comments also are given about global or selective erasure of data. 

Wilhelm Ostwald was also defining physical chemisti y during the 1880s. As an editor of a new journal devoted to physical chemisti y, he wrote brief critical comments about many papers. Reviewing a paper that used Liebig s vibrational theoi y to explain results, Ostwald provided a new definition of a catalyst that was widely accepted and led to his being awarded the Nobel Prize in 1909. 

With the publication of Vol. 51, the editors and the publisher would like to take this opportunity to thank authors and readers for their collaboration and their efforts to meet the scientific requirements of this series. We appreciate our authors concern for the progress of Polymer Science and we also welcome the advice and critical comments of our readers. 

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report ... 

We thank Dr W. Griffith Humphreys and Dr Mingshe Zhu for critical comments and helpful discussion. 

The author thanks Alan Winter (Glasgow) for critical comments and discussions regarding this chapter. This work is funded by the Medical Research Council through the award of an MRC Senior Fellowship. 

The work described was supported by grants from The Wellcome Trust (UK) to G. D. P. We thank members of the Pavitt laboratory for critical comments on the manuscript. 

The report of the first zinc compound with a Zn-Zn core elicited a number of critical comments on the structure and bonding of decamethyldizincocene, and the interpretation of the results.236,237 None of the authors of these commentaries questioned the data or their interpretation. Parkin, however, has pointed out that the formal oxidation state of +1 for zinc in this compound is merely due to the convention that metals are assigned an oxidation state of 0 when they form bonds with like atoms.237 If the conventional definition of valence, namely the capacity of atoms to form bonds to other atoms is used, then the zinc atoms in decamethyldizincocene are not monovalent, but divalent. The synthesis of a paramagnetic organozinc compound in which zinc uses only one of its two 4s electrons will remain an interesting challenge to many synthetic organometallic chemists. 

This review was stimulated, in large part, by the work of the several collaborators in the group, both past and present O. Caille, C. Hassler, H. Kola, M. Martin, N. Mirimanoff, A. Smiejan, V. Slaveykova, M. Tuveri and I. Worms. Their critical comments, results and discussions were extremely helpful in improving earlier drafts of the manuscript. We also greatly appreciate the critical reviews of J. Galceran, H. P. van Leeuwen and C. Rossier. This work was supported, in part, by the Swiss National Funds 2000-050529.971 and the European Union 5th framework BIOSPEC project (EVK1-CT-2001-00086). 

K. Matyjaszewski and S. Penczek. Private communications. Although it is unusual to heed unpublished critical comments, it will be seen that the privately expressed views of these experienced colleagues have catalysed a useful advance in our understanding. 

The heyday of differential centrifugation and work on isolated cell fractions was short. In the 1940s and 1950s biochemists attracted much critical comment because of their use of disorganized homogenates and then of separated cell fractions. Many metabolic pathways were, however, successfully analyzed with little reference to their normal setting within the cell. 

Acknowledgments We would like to thank Steffen Gurke and Joao Barroso for critical comments on the text and the Norwegian Research Council for financial support (project number 164959/V40). 

This topic draws from a variety of fields of study. We are grateful for critical comments and thoughtful suggestions on earlier drafts of this chapter from Steven Benner, Peter R. Buseck, Kenso Soai, and Frank H. Westheimer. Any mistakes and omissions remain the responsibility of the authors. 

We are unable to critically comment on the numerical values of kuala shown in Fig. 9 since Eq. (32) cannot be used to make an independent... 

Ld like to thank Jun-ichi Nakayama for his valuable information and Makoto Tachibana for his critical comments. 

Critical comments and helpful discussions from K. U. Ingold, R. Merenyi, C. Riichardt, L. Stella and H. G. Viehe are acknowledged. 

Acknowledgement. Generous support of the work carried out in the author s laboratory by Deutsche Forschungsgcmeinschaft. Fonds der Chemischen Industrie and BASF Aktiengesell-schaft is gratefully acknowledged. The author expresses thanks to Drs. A. C. Testa, St. Johns University, New York, and J. CorneUsse, Rijksuniversiteit Leiden, for critical comments on the manuscript. 

Siegwart Y, Some critical comments on the legislative control of flavouring in food, FlavourFragr/8 87—90, 1993. 

Geiger, H. and Markham, K.R., The H-NMR spectra of the biflavones isocryptomerin and cryptomerin B. A critical comment on two recent publications on the biflavone patterns of Selaginella selaginoides and S. denticulate, Z. Natursforsch., 51, 757, 1996. 

I am gratefully indebted to Andreas Hartmann, M.D., and Rainer Rupprecht, M.D., for their critical comments in the preparation of this manuscript. 

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