1,720,958 research outputs found
Using Preparative Column for HPLC to Separate and Purify the Catechins in Tea
No full text茶湯以100℃之沸水沖泡五分鐘後，取其濾液5耐將其通過Lichrolut RP-18 (500mg)之固相萃取管，以試管收取其濾液A，再以2ml MeCN/pure water之溶液5/95清洗後收集濾液B，再以2ml CN/pure water之溶液15/85之溶液清洗後收集濾液C,再以2ml MeCN/pure water之溶液30/70之溶液清洗後收集濾液D，再以2ml MeCN/pure water之溶液100/0之溶液清洗後收集濾液E，結果A中僅檢測出極性小的元素及少量咖啡因，EGC兒茶素於B及C濾液中檢出，D及E中則無，+C兒茶素在B及C中檢出，其量極微且其附近雜質多較不易分離。EC兒茶素在C及D中檢出，B中微量，A及E中則無，EGCG在C及D中檢出，其量極大且其PEAK附近幾無其他雜質，因而在純化過程中較為容易析出。ECG在C及D中檢出，D中之量為C中之10倍，其量極大且其PEAK附近幾無其他雜質，因而在純化過程中較為容易析出。E之濾液幾無EGC、＋C、EC、EGCG、ECG等兒茶素類及CAFFEINE。
Tea liquor was using 100¢XC of boiled water to extract, then took out 5 ml of filtrated liquor, let them go through the column of Lichrolut RP-18(500mg) made by MERCK CO., which column was for solid phase extraction. Collected the filtrate with a test tube as solution A for HPLC catechins’s test. Use another 2 ml of MeCN/pure water solution of 5/95 percent with respectively to go through the column for solid phase extraction again. Collected the filtrate with another test tube as for solution B. Then use another 2 ml of MeCN/pure water solution of 15/85 percent with respectively to go through the column again. Collected the filtrate with another test tube as for solution C. After that use another 2 ml of MeCN/pure water solution of 30/70 percent with respectively to go through the column again. Collected the filtrate with another test tube as for solution D. Finally use extra 2 ml of MeCN/pure water solution of 0/100 percent with respectively to go through the column for the last solid phase extraction. Collected the filtrate with another test tube as for solution E. The tested results by using the HPLC for analysis, the solution A could only be detected the low polarity elements and a very few amount of Caffeine, The catechin of EGC was detected in solution B and C, but couldn’t find in solution D and E. The catechin of +C was detected in solution B and C in very less amount, where peaks in the time table around showed more complicate elements as respective. It’s means that the catechin of +C is hard to separate. The catechin of EC was detected in solution C and D, also very few in solution B and couldn’t find any in solution A and E. The catechin of EGCG was detected in solution C and D with very large quantity, where peaks in the time table showed almost no other elements in the around. It’s means that the purify procedure for the catechin of EGCG is more easy than the others as respective. The catechin of ECG was detected in solution C and D, also with large quantity. The quantity in D was about the 10 times of that in C. The amount of ECO was huge, where peaks in the time table showed almost no other elements in the around. It’s means that the purify procedure for the catechin of ECG is more easy than the others as respective. The filtrate of solution E couldn’t find any of the cate chins content and caffeine as respective
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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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