Polyanthos


Book Description




The Polyanthos


Book Description




The Polyanthos


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Transactions


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Plants of British Columbia


Book Description

This book is an up-to-date checklist of the current valid taxonomyfor all vascular plants, bryophytes, and lichens in British Columbia,including synonyms, species codes, and other information. A convenient,geographically restricted, comprehensive checklist like this one willaid greatly in avoiding the present confusion concerning the names ofmany species in the ecological and systematic literature, as well as inapplied fields. The book is organized into three sections. Part 1 organizes speciesalphabetically according to taxonomic order by families of vascularplants, bryophytes, and lichens. Within each family, the genera arelisted alphabetically, along with any synonomies (former names) andcommon names. In Part 2 species are organized alphabetically accordingto their scientific names. Part 3 lists common names followed by theirscientific names. Excluded names (names inappropriately applied toplants in B.C.) are given in an appendix. Those familiar with planttaxonomy will find Part 1 particularly helpful when checkingnomenclature; semi-professionals familiar with scientific names willuse Part 2 and then Part 1; those who know only common names will checkPart 3 and then Part 2 and Part 1 to determine families. There is presently considerable confusion about many species namesin B.C. Plant names change for many reasons and new plants invade.Information about plants in B.C. is scattered in several checklists,most of them incomplete or out of date; for some species, such asliverworts, no provincial checklist even exists. This checklisttherefore will be useful to all professionals working with vegetationand for students in agriculture, botany, ecology, forestry and othersciences. Although the focus is on B.C., the book will also be usefuloutside the province, particularly in the northwest American states andin Alberta and the Yukon.




The Gardeners Dictionary


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Fortschritte der Chemie organischer Naturstoffe / Progress in the Chemistry of Organic Natural Products


Book Description

The chemistry of condensed tannins has hitherto represented a relatively unattractive and therefore neglected area of study; one in which the weight of research effort involved is invariably disproportionate to the results achieved, in which the participating schools generally confine their approach to specific molecular species, and in which as yet no consensus has been reached regarding likely precursors. The problems which beset those engaged in this field represent a combined function of the abnormal complexity of the gradational range of oligomers of increasing mass and affinity for substrates which typify most extracts rich in tannins, and the consequent problem of their isolation and purification, the high chirality of tannin oligomers, the need to contend with the phenomenon of dynamic 'rotational isomerism about interflavanoid bonds in the IH n.m.r. spectral interpretation of their derivatives, the lack of precise knowledge regarding the points of bonding at nucleophilic centres, and the obvious limitations of a hitherto predominantly analytical approach. The last of these reflects the need for a general method of synthesis which permits unambiguous proof of both structure and absolute configuration also at higher oligomeric levels. With these objectives in mind we initiated a purely synthetic approach based on the premise that flavan-3,4-diols as source of electrophilic flavanyl-4-carbocations, and flavan-3-0Is as nucleophiles (cf 1,2) represent the prime initiators of a process of repetitive condensation in which the immediate products also represent the sequent nucleophilic substrates.