Effects Of Ring Formation Research Articles

Effect of ring formation on burner flame stability in lime kilns

Ring formation in lime kilns is a common problem in pulp mills. Unstable burner operation that causes wide temperature variations within the kiln has been shown to be a main contributor. As rings grow thicker and longer, they are expected to affect the burner flame pattern, alter the temperature distribution, and further aggravate the problem. This study systematically examines the effect of rings on burner operation as a function of primary air and ring characteristics, using a laboratory mock kiln. The results show that primary air greatly affects the burner flame pattern and stability. Without a ring, the flame is brighter and shorter, with an increase in primary air (PA) up to 17%, and blows out at 20% PA or higher. In the presence of a ring, the flame becomes unstable and blows out when the ring is placed near the burner, but it is more stable when the ring is placed away from the burner. Thick and long rings destabilize the flame more than thin and short rings.

Statistical Mechanics of Sterically Interacting Ring Polymers

This paper derives a new model describing sterically interacting polymers in a solution, a finite fraction of which forms closed rings. The model is closely related to a magnetic partition function for classical spin model, but vanishing limit ( n →0) for the internal degrees of freedom is not assumed. For given average molecular weights and amounts of ring and chain fractions, the number of spin components is uniquely determined. The osmotic pressure and the single chain end-to-end distance are obtained in the case of an athermal solvent. The effect of ring formation is discussed.

Flow of materials in rotary kilns used for sponge iron manufacture: Part III. Effect of ring formation within the kiln

The formation of accretions or ’rings’ in rotary kilns used for the manufacture of directly reduced iron (sponge iron) affects the residence time of the charge, kiln hold-up, and the kiln output to a great extent. In this part of the work, the effect of ring formation was simulated at room temperature in a scaled-down model of a rotary kiln by inserting conical dams in the shape of frustrums of cones through the feed end of the kiln. The influence of such conical dams on various operating parameters was evaluated.

Studies on Long-range Couplings between 77Se and 13C in Some Aryl Selenides, Dichlorides, and Selenoxides. The Inverse Effect on Couplings in the Selenoxide Formation

Abstract Long-range coupling constants between 77Se and 13C in selenoanisole, diphenyl selenide, diphenyl diselenide, and their 2-mono- and 2,2′-disubstituted derivatives, selenoxanthone, selenanthrene, dichlorides, and selenoxides were measured to disclose predominant factors governing the magnitude of the coupling. Extraordinary large values for two- and three-bond couplings are found in selenoxanthone. Three factors are operative: the orientational effect, the coordination number, and the effect of ring formation. The last factor accompanies a stronger inverse effect on the coupling of selenoxides than on that of selenides.

Viscosity, Sedimentation, et Cetera, of Ring- and Straight-Chain Polymers in Dilute Solution

The hydrodynamic properties of straight-chain and ring-chain polymers whose dimensions are expanded over those of similar Gaussian coils have been calculated by a perturbation method based on the normal-coordinate treatment with hydrodynamic interaction. Expansion is characterized by a parameter ε, such that the mean-square length is proportional to N1+ε, N being the number of chain segments. For straight chains the intrinsic viscosity, expressed in terms of the Flory Φ (×10−23), decreases from 2.81 at ε=0 to 0.686 at ε=0.5, while for rings Φ varies from 1.85 to 0.422; the ratio straight:ring increases slowly from 1.5 to 2.0. The sedimentation coefficient of the straight chain increases by a factor of 2.4 over this range of ε, while that of the ring goes up 2.2-fold. The ratio straight: ring rises slowly from 0.85 to 0.91. The results on straight chains agree with those of previous workers, and the straight:ring ratio agrees with several experiments on the sedimentation of straight and ring forms of various DNA's. It is apparent that viscosity should be a much more sensitive measure of ring formation than sedimentation, and that the effect of ring formation is roughly the same regardless of chain expansion (i.e., the same both in Gaussian coils and in a stiff chain such as DNA).

Dilute Gelling Systems. I. The Effect of Ring Formation on Gelation

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDilute Gelling Systems. I. The Effect of Ring Formation on GelationR. W. KilbCite this: J. Phys. Chem. 1958, 62, 8, 969–971Publication Date (Print):August 1, 1958Publication History Published online1 May 2002Published inissue 1 August 1958https://doi.org/10.1021/j150566a019RIGHTS & PERMISSIONSArticle Views100Altmetric-Citations68LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (336 KB) Get e-Alerts

The Effect of Ring Formation on Optical Rotatory Power. A Comparison of the Optical Rotations of 2-Phenylcyclopentanone and of Some Acyclic α-Phenyl Ketones

The Effect of Ring Formation on Optical Rotatory Power. A Comparison of the Optical Rotations of 2-Phenylcyclopentanone and of Some Acyclic α-Phenyl Ketones

CLXXXVI.—The effect of ring-formation on viscosity

CLXXXVI.—The effect of ring-formation on viscosity