The effect of rare earth additions on low alloy steel

Rare earth metals have for some years been used as an inoculant in nonferrous foundry practice and lately in the production of nodular iron. It has been reported that addition of rare earth metal to certain grades of stainless steel so improve the hot malleability that reduction of large size ingots in the blooming mill is now possible. It has been reported that considerable improvement in soundness and mechanical properties of steel castings and wrought products have been attained as a result of small additions of rare earth metals and oxides. In practically all investigations, it has been reported that most of the properties such as workability, strength, impact properties, and oxidation resistance, improve by the addition of about two pounds per ton of rare earths. Some of the authors consider rare earth metal additions as a penicillin for steel castings in solving production difficulties. There have been some contradictions as to the degree of improvement affected by rare earth additions, but none of the useful properties of steel have been found to be impaired. The American Metallurgical Products Company of Pittsburgh, Pennsylvania has even recommended a new system of steels being developed with rare earth additions. The present investigation was undertaken to extend the information on improvement in properties and to find some causes of the drastic effects of rare earths. The work has been confined to low alloy steel composition, which is best suited for the production of steel castings. The various phases of the study included grain size determinations, desulfurization effects, as also the examination of inclusions, all of which affect properties of steel considerably. The properties of rare earth metals have been studied and an effort made to analyze the thermodynamic possibilities of their action. The use of fluorides of rare earths was included to see if they have the same effect as oxides and metals. The investigation will be useful to show the effects more clearly on the steel quality, by the addition of rare earth elements, and may help in deciding upon the application of these elements for certain specific steels --Introduction, pages 1-2

Malkanguniol, one of the polyalcohols from celastrus paniculatus willd

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Stereochemistry of malkanguniol and stereostructures of some other related polyalcohols from celastrus paniculatus willd

This article does not have an abstract

Studies in sesquiterpenes-XVIII. The proton magnetic resonance spectra of some sesquiterpenes and the structure of humulene

The nuclear magnetic resonance spectra of longifolene, zerumbone, humulene, and their hydroderivatives have been studied in order to gauge the potentialities of this new tool in the field of sesquiterpenes. On the basis of present study, it has been possible to unequivocally fix the positions of the ethylene linkages in humulene and thus provide a straightforward solution of this hitherto unsolved problem

Impact of natural products in modern drug development

191-198Usage of natural substances as therapeutic agents in modern medicine has sharply declined from the predominant position held in the early decades of last century, but search for bioactive molecules from nature (plants, animals, microflora) continues to play an important role in fashioning new medicinal agents. With the advent of modern techniques, instrumentation and automation in isolation and structural characterisation, we have on hand an enormous repository of natural compounds. In parallel to this, biology has also made tremendous progress in expanding its frontiers of knowledge. An interplay of these two disciplines constitutes the modern thrust in research in the realm of compounds elaborated by nature. The purpose of this article is to underline how natural products research continues to make significant contributions in the domain of discovery and development of new medicinal products. It is proposed to present the material under several heads, each of which has made natural products research relevant in the search for new and better medication

Impact of natural products in modern drug development

Usage of natural substances as therapeutic agents in modern medicine has sharply declined from the predominant position held in the early decades of last century, but search for bioactive molecules from nature (plants, animals, microflora) continues to play an important role in fashioning new medicinal agents. With the advent of modern techniques, instrumentation and automation in isolation and structural characterisation, we have on hand an enormous repository of natural compounds. In parallel to this, biology has also made tremendous progress in expanding its frontiers of knowledge. An interplay of these two disciplines constitutes the modern thrust in research in the realm of compounds elaborated by nature. The purpose of this article is to underline how natural products research continues to make significant contributions in the domain of discovery and development of new medicinal products. It is proposed to present the material under several heads, each of which has made natural products research relevant in the search for new and better medication

Guggulterols: a new class of naturally occurring lipids

This article does not have an abstract