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Studies on the constituents of the bark of Chamaecyparis formosensis Matsum. and the whole herb of Waltheria americana L.
No full text紅檜 (Chamaecyparis formosensis Matsum.) 樹皮，以甲醇浸泡得到之萃取物，利用矽膠薄層分析、高效能液相分析儀以及再結晶方式，分離到單萜類 1 個、倍半萜類 1 個、雙萜類 20 個、固醇類 2 個、芳香族類 4 個，共 28 個化合物。其中有 10 個新化合物和 1 個從天然物首次分離得到的化合物。
倒地麻 (Waltheria americana L.) 全草，以丙酮浸泡得到之萃取物，再利用矽膠薄層分析、高效能液相分析儀以及再結晶方式，共分離到三萜類 5 個、固醇類 8 個、類黃酮類 1 個、色酮類 1 個、芳香族類 2 個、其他類 1 個，共 18 個化合物。其中有 2 個從天然物首次分離得到的化合物。
這些化合物經測得紅外線光譜、質譜、氫-核磁共振圖譜、碳-核磁共振圖譜後，搭配二維核磁共振圖譜，並參考相關文獻以確認其結構。Chamaecyparis formosensis Matsum. is indigenous in the north and central parts of Taiwan at 1000~3000 meters, often forming pure stands or mixed with Chamaecyparis obtusa var. formosana. This trees can attain 1500 years of age, and sometime it can live about 4000 years old , Their longevity is attributable to the tree's inherent ability to withstand erosion and prevent the growth of bacteria on its bark.
The methanol extract from the bark of Chamaecyparis formosensis Matsum. was concentrated to give residue which was partitioned between ethyl acetate and water. The ethyl acetate layer was separated by column chromatography on silica gel and HPLC afforded twenty-eight compounds. Of these compounds, ten compounds are new and one compound are isolated for the first time from natural sources.
Waltheria americana L. grows throughout the tropics and warmer subtropics. It is a short-lived shrub or subshrub and usually has a single, strong stem emerging from the ground, but frequently branches near the ground. However, in some environments, it may grow in a semiprostrate habit. This plant has several medicinal applications. For example, in Polynesia the root bark is chewed upon for sore throat, while in Hawaii it is used internally for arthritis, neuralgia, and asthma.
Fractionation and chromatography of the acetone extract from Waltheria americana L. afforded eighteen compounds. From these compounds, two compounds are isolated for the first time from natural sources.
The structure of these compounds were elucidated by comparison of their spectral data with related literature values and spectroscopic methods including 1D and 2D NMR.中文摘要-----------------------------------------------------------------------------------I
英文摘要-----------------------------------------------------------------------------------III
一、緒論
第一節：研究目的-----------------------------------------------------------1
第二節：紅檜植物簡介以及成分回顧-----------------------------------2
第三節：倒地麻植物簡介以及成分回顧--------------------------------12
二、結果與討論
第一節：萃取與分離-------------------------------------------------------16
第二節：紅檜樹皮之新化合物構造鑑定
化合物D2結構鑑定------------------------------------------------------30
化合物D3結構鑑定------------------------------------------------------38
化合物D4結構鑑定------------------------------------------------------47
化合物D6結構鑑定------------------------------------------------------55
化合物D7結構鑑定------------------------------------------------------62
化合物D8結構決定------------------------------------------------------70
化合物D12結構鑑定-----------------------------------------------------77
化合物D13結構鑑定-----------------------------------------------------85
化合物D16結構鑑定-----------------------------------------------------94
化合物D19結構鑑定----------------------------------------------------102
化合物ST1結構鑑定----------------------------------------------------110
第三節：倒地麻全草之新化合物結構鑑定
化合物PH1結構鑑定----------------------------------------------------119
化合物ST10結構鑑定---------------------------------------------------128
三、結論
第一節：化合物之骨架種類---------------------------------------------- 137
第二節：Labdane類化合物之光譜特徵-------------------------------- 141
四、實驗部份
第一節：實驗儀器與藥品----------------------------------------------------143
第二節：實驗步驟-------------------------------------------------------------145
第三節：化合物數據----------------------------------------------------------148
五、參考文獻-------------------------------------------------------------------------------15
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koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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