Zobrazeno 1 - 10
of 92
pro vyhledávání: '"Richard W. Hemingway"'
Publikováno v:
Journal of Wood Chemistry and Technology. 20:415-439
The presence of knots or heartwood influences the amount and composition of volatile organic compound (VOC) emissions associated with drying of southern pine lumber. Experimental kiln charges of lumber containing 0 to 5% of knot volume gave VOC emiss
Autor:
Catherine S. Canady, William B. McGraw, Gerald W. McGraw, Leonard L. Ingram, Richard W. Hemingway
Publikováno v:
Environmental Science & Technology. 33:4029-4033
Emissions from wood dryers have been of some concern for a number of years, and recent policy changes by the Environmental Protection Agency have placed emphasis upon the gaseous emissions that lead to the formation of particulate matter as small as
rd This book has been developed from the proceedings of the 3 Tannin Confer ence honoring Professor Edwin Haslam, Department of Chemistry, University of Sheffield, for his efforts and outstanding contributions to the field of plant polyphe nols.
Autor:
Richard W. Hemingway, Peter E. Laks
This book was developed from the proceedings of the 2nd North American Tan nin Conference held in Houghton, Michigan, June, 1991. The objective of this con ference was to bring together people with a common interest in plant polyphenols and to pr
This book was developed from the proceedings of the first North American Tannin Conference held in Port. Angeles, Washington, August 1988. The objective of the conference was to bring together people with a common interest in condensed tannins and to
Publikováno v:
Journal of Wood Chemistry and Technology. 17:341-360
To investigate the reactions that occur in the flavanoid unit during the liquefaction of tannin in phenol, the phenolysis of (+)-catechin was studied using either H2SO4, HCl, or BF3 2H2O as acid catalyst. In addition to 2-[3-(3,4-dihydroxyphenyl)-2-h
Autor:
Richard W. Hemingway, Petrus J. Steynberg, G. Wayne McGraw, Daneel Ferreira, Jan P. Steynberg
Publikováno v:
Journal of the Chemical Society, Perkin Transactions 1. :2395-2404
Acetic acid-catalyzed cleavage of proanthocyanidins in the presence of phloroglucinol gives a series of 2R procyanidin- and prodelphinidin-phloroglucinol adducts together with a novel 2S all-cis derivative implicating cleavage of the pyran ring and s
Autor:
Richard W. Hemingway, Tsutomu Hatano
Publikováno v:
Journal of the Chemical Society, Perkin Transactions 2. :1035-1044
NMR studies of catechin-(4α→8)-epicatechin (1) and catechin-(4α→8)-catechin (2) provided complete assignment of the proton and carbon resonances for both the more extended and compact conformers in the free phenolic form. When 1 is in organic s
Autor:
Daneel Ferreira, Jan P. Steynberg, Richard W. Hemingway, Petrus J. Steynberg, E. Vincent Brandt
Publikováno v:
Journal of the Chemical Society, Perkin Transactions 1. :1943-1950
The natural occurrence of the first oligomeric profisetinidins with (2R,3R)-2,3-cis-epifisetinidol chain extender units is demonstrated in the bark of Pithecellobium dulce (Guamuchil). Semi-synthesis using the appropriate flavan-3-ol and flavan-3,4-d
Publikováno v:
Magnetic Resonance in Chemistry. 34:424-433
Studies of flavan-3-ols in their biologically significant phenolic form show that both H-6 and C-6 resonances are downfield from H-8 and C-8. Therefore, assignments for the H atoms of the A-ring are inverse to those commonly reported. By contrast, in