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First article

A few years after the first articles of Breslow had appeared, Grieco elegantly demonstrated that the astonishing rate and selectivity enhancements of Diels-Alder reactions in water can be exploited sirccessfully in organic synthesis. He extensively studied the reactivity of dienes containing... [Pg.27]

In this section, we will describe the principal features of the main methods and the information that the Rietveld analysis generally delivers, especially related to the investigations on poor crystallites and multiphase compounds. This introduction is not exhaustive there are hundreds of articles that explore practically all of the aspects of this kind of analysis and now, 40 years after the first article [43], new improvements and results are still being published. [Pg.135]

Two other publications on Ir (73 keV) Mossbauer spectroscopy of complex compounds of iridium have been reported by Williams et al. [291,292]. In their first article [291], they have shown that the additive model suggested by Bancroft [293] does not account satisfactorily for the partial isomer shift and partial quadrupole splitting in Ir(lll) complexes. Their second article [292] deals with four-coordinate formally lr(l) complexes. They observed, like other authors on similar low-valent iridium compounds [284], only small differences in the isomer shifts, which they attributed to the interaction between the metal-ligand bonds leading to compensation effects. Their interpretation is supported by changes in the NMR data of the phosphine ligands and in the frequency of the carbonyl stretching vibration. [Pg.328]

An autocatalytic reaction is one in which the reaction rate is proportional to a product concentration raised to a positive exponent. Some of the first articles in the literature of chemical kinetics deal with reactions of this type. For example, in 1857, Baeyer (12) reported that the reaction of bromine with lactose was autocatalytic. The hydrolyses of several esters also fit into the autocatalytic category, since the acids formed by reaction give rise to hydrogen ions that serve as catalysts for subsequent reaction. Among the most significant autocatalytic reactions are the fermentation reactions that involve the action of a microorganism on an organic feedstock. [Pg.338]

After this magnificent display, I have a feeling that their eternally tetchy prototype production department asked the morose tech to rework and fix the power supply himself ( we only make first articles, and you know that ). [Pg.57]

Lemieux and Spohr (Alberta) here trace our understanding of enzyme specificity in broad perspective as they assess Emil Fischer s lock and key concept advanced a century ago in relation to current ideas of molecular recognition. It may be noted that the very first article in Volume 1 of Advances, by Claude S. Hudson, was devoted to the Fischer cyanohydrin synthesis and the consequences of asymmetric induction. [Pg.416]

Because of the outbreak of World War I and perhaps because of the delay in his receiving patents on coal hydrogenation, Bergius published nothing on his process until 1921. This is the first article along with American patents 1,342,790 June 8, 1929 (filed April 18, 1916) and 1,291,664, September 27, 1921 (filed April 18, 1916) in which Bergius discussed his continuous process. [Pg.50]

Mulliken, who published the first articles in his series, "Electronic Structures of Molecules and Valence," in Physical Review, was not keen initially on the new journal but nonetheless shifted his series to the Journal of... [Pg.270]

The extension of the term isotactic to condensation polymers was made by Natta in his first article discussing poly-L-a-amino acids (22). In itself the term isotactic is redundant here as the configuration of the repeating unit is sufficient to identify the macromolecular stmcture. It is, however, useful to distinguish a system, racemic or not, in which each macromolecule is composed of only l or only D residues from a mixture of macromolecules made up of random or alternate sequences of L or d units. Similarly the term syndiotactic serves in the identification of oligopeptides or polypeptides composed of alternate sequences of D and L units, like those synthesized by Lorenzi and Tomasic (77). [Pg.12]

The influence of the solvent on chiroptical properties of synthetic polymers is dramatically illustrated in the case of poly (propylene oxide). Price and Osgan had already shown, in their first article, that this polymer presents optical activity of opposite sign when dissolved in CHCI3 or in benzene (78). The hypothesis of a conformational transition similar to the helix-coil transition of polypeptides was rejected because the optical activity varies linearly with the content of the two components in the mixture of solvents. Chiellini observed that the ORD curves in several solvents show a maximum around 235 nm, which should not be attributed to a Cotton effect and which was interpreted by a two-term Drude equation. He emphasized the influence of solvation on the position of the conformational equilibrium (383). In turn, Furakawa, as the result of an investigation in 35 different solvents, focused on the polarizability change of methyl and methylene groups in the polymer due to the formation of a contact complex with aromatic solvents (384). [Pg.86]

Interesting reagents for such MCRs from the viewpoint of selectivity tuning are 5-aminopyrazoles containing carboxamide substituent. In the first article concerning the behavior of these aminozoles in the reactions with cyclic 1,3-diketone and aldehydes, it was found that only one direction of the treatment leads to tricyclic Biginelli-like heterocycles 61 (Scheme 30) [96]. [Pg.61]

Antoine Court de Gebelin publishes the first article on the occult Tarot in volume eight of Monde Primitif. [Pg.123]

The first article in this volume, by Jenny P. dusker, treats general aspects of metal liganding to functional groups in proteins. This article presents a detailed summary of the geometry of interaction of metals with the various chemical groups of proteins. It also presents, in Sections I through VIII, a lucid development of the principles and terminology of the field of metal-protein interactions. It is with these sections that the newcomer to the field of metalloproteins should start. [Pg.405]

Research spending in the pharmaceutical industry is carried out in the context of considerable interfirm rivalry. 1 emphasized that point in my first article on this topic (Comanor 1964) but provided no formal model of the process. Since that time, there have been more formal discussions of these issues. A particularly lucid one is offered by Cockburn and Henderson (1994), which emphasizes the competitive nature of the drug discovery process. [Pg.69]

Received September 12, 1962. Second in a series on Phorsphorus-Fluorine Chemistry. The first article will soon appear in the Journal of Inorganic and Nuclear Chemistry. [Pg.164]

Professor Grubbs recently published (J, Am. Chem. Soc. 125 10103, 2003 J. Am. Chem. Soc. 125 11360, 2003) two detailed articles on activation and selectivity in this reaction. The first article addresses variations on catalyst design. The second paper defines several types of alkenes, and lays out rules that allow one to predict which pairs of alkenes will dimerize efficiently. While it is not possible to summarize all of their results in this limited space, some highlights include ... [Pg.19]

First article inspection Acceptance sampling According to a quality plan 100% inspection... [Pg.228]

Bonding the first article to the second article along the interface area. [Pg.51]

The first article may be a polymer composition with a COC as basic material. Suitable low crystallinity polymers to fabricate the second article include COCs and blends of COCs with poly(methyl pentene), other polyolefins, and styrenics. [Pg.51]

In the present collection of Ya.B. s papers we have included primarily his first articles which formulate the basic ideas and concepts that were then worked out mathematically and thoroughly verified both in later papers by Ya.B. and in the papers of his many students. Moreover, the modern science of combustion all over the world is developing now along the paths outlined in Ya.B. s papers. [Pg.20]

In 1998, the Sacchi group published the first article dealing with the geographical characterization of olive oils by using 1H NMR spectroscopy and multivariate statistical analysis (Sacchi et al., 1998). In this paper, 55 EVOO samples, obtained from different olive varieties and coming from four Italian regions (Campania, Lazio, Sicily, and Umbria), were... [Pg.106]

Synthetic fibres may be made from cellulose or plastics. Hilaire Chardonnet made the first synthetic fibre from cellulose in 1889. Wallace Carothers made the first plastic-based synthetic fibre nylon in 1935. Ladies stockings were the first articles to be made of nylon. Second World War gave a boost to the production of nylon. [Pg.80]


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See also in sourсe #XX -- [ Pg.42 ]

See also in sourсe #XX -- [ Pg.42 ]

See also in sourсe #XX -- [ Pg.42 ]




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