Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 176 for “"birch"”.
-
Birch reduction of cinnamic acid
… (3). Little additional work was reported until Birch and his co-workers picked up the investigation in the early 1940's. It was through his vigorous study and development of this reduction system that Birch's name came to be associated with reductions of organic compounds by alkali metals in …
-
The basic density of Scotch pine, Norway spruce, common birch and white birch in southern Finland
Thesis (M.S.)--Michigan State University. Dept. of Forest Products, 1966
-
Birch reduction of benzenesulfonamide and benzenephosphonic acid
… of aromatic compounds, commonly known as the BIrch reduction, has proven to be a synthetic procedure of great utility. (1) The flexibility and usefulness of this reaction has attracted increasing attention in recent times, primarily by BIrch (1,2). The overall reaction occuring during the …
-
The Birch and Swinnerton-Dyer Conjecture for elliptic curves
… dissertation is to provide an exposition of the Birch and Swinnerton-Dyer Conjecture, considered by many to be one of the most important unsolved problems in modern Mathematics. A review of topics in Algebraic Number Theory and Algebraic Geometry is provided in order to provide a characterisation …
-
A study of the Birch reduction of m-Methoxybenzamide
<p>This thesis is (1) an investigation in the identity of the unknown material Qazi (20) obtained when benzamide was reduced at the boiling point of ammonia with 3.3 equivalents of sodium and ethanol, (2) characterization of the components of the brown liquid obtained when m-methoxybenzamide was …
-
Governance Attributes Influencing the Expansion of Birch Woodlands in Iceland
Þessi rannsókn skoðar stjórnunartengda þætti sem hafa áhrif á endurheimt birkiskóga á Íslandi, með sérstakri áherslu á sögulegt samhengi og samsetningu stjórnkerfis birkiskóga og samskipti innan þess, á þeim tíma sem rannsóknin var framkvæmd. Áður fyrr voru birkiskógar útbreiddir um allt land, en …
-
Birch reduction of benzamide, m-methoxy-benzamide and terephthalic acid
… In a variety of experimental procedures for Birch reduction at dry-ice temperature (-65 to -78°C), benzamide was reduced to 1,4-dihydrobenzamide: (a) By using Niem’s procedure (27), with lithium and ethanol in liquid ammonia at dry-ice temperature and where ethanol was added slowly after …
-
Treeline of mountain birch (Betula pubescens Ehrh.) in Iceland and its relationship to temperature
Die Waldfläche der Moorbirke (Betula pubescens Ehrh.) in Island wurde zwischen der Besiedlung des Landes durch die Wikinger ab 874 n. Chr. und heute dramatisch reduziert. Ursachen des Rückgangs waren v. a. grossflächige Nutzung des Waldes für die Produktion von Holzkohle, Verbiss durch frei …
-
Exploring new reactions with Organic Electron Donors and the complexities of the Birch reduction
… which is conveniently prepared during the Birch reduction. In this work, the Birch reduction conditions were successfuly applied, in an unprecedented way, to the C-S bond cleavage of methyl-coenzyme M (MeCoM). The experimental results have the potential to contribute significantly towards …
-
The influence of plant size and fertilization on catkin production in birch (Betula pubescens Ehrh.)
Downy birch Betula pubescens Ehrh. is the only tall growing native birch species in Iceland. Around the time of the settlement, birch woodlands used to cover large areas of Iceland, but today only little is left. Regeneration of birch is a key process in woodland expansion and is important for land …
-
Exploration of Synthetic Pathways to Quaternary Carbon Stereocenters and Fused Ring Systems via Birch Reductions
<p>The Birch reduction – alkylation is an effective way to form all-carbon quaternary centers from inexpensive commercially available starting material. When coupled to complementary reactions such as the Rauhut-Currier or Mizoroki-Heck, complex drug-like structures can be rapidly formed. We have …
-
Ecological Factors Influencing Infection Rates of the Birch Polypore Inonotus obliquus in the Laurentian Mixed Forest Province
… </em>a conk forming polypore parasitic to birch (<em>Betula </em>spp<em>.</em>) trees in northern hardwood forests around the world, has been harvested intensively in recent years for its potentially medicinal properties. However, there is a dearth of ecological understanding of this …
-
Effects of nitrogen and water on growth, photosynthesis, and leaf properties of deciduous tree species with consequences for gypsy moth herbivory
… and insect herbivory. I grew seedlings of gray birch (Betula populifolia), yellow birch (B. alleghaniensis), and red oak (Quercus rubra) for two years under varying levels of N and water availability in the field. Growth and biomass allocation were examined for the three species. Photosynthetic …
Page 1 of 9