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Synthesis diblock copolymer and it’s application
No full text在本篇論文中，我們將親水端聚乙二醇甲基醚(polyethylene glycol methyl ether)的末端以醯胺鍵結(amide link)的方式將三級碳溴2-溴-2-甲基丙醯溴(2-bromoisobutyryl bromide)連接上親水端做為巨始劑。利用ATRP(atom transfer radical polymerization)合成出疏水端為丙烯酸甲酯(methyl acrylate)的雙區塊聚合物。利用所合成的雙區塊聚合物在酸性水溶液下來進行孔洞性材料的合成，可以觀察到孔徑(pore size)隨疏水端的增加而增大。而在EO45-N-MA28和EO45-N-MA63、EO114-N-MA113為模板可以合成出立方結構(Im3m)和二維六角排列(p6mm)的特殊結構。
接下來在疏水端(MA)上做3-疊氮丙胺(3-azido-propylamine)官能基的修飾，以反應的時間控制修飾的數量，並且進一步修飾含鈀(Pd)與鎢(W)的金屬錯合物。由於金屬修飾在疏水端上，所以金屬氧化物的粒子會均勻的分散在孔洞裡面，而不是隨機的分佈在孔洞中或是孔壁內，使得金屬的表面是一個完完全全暴露在孔洞內的金屬氧化物。而含鈀和含鎢金屬的矽氧孔洞材料在Suzuki coupling與烯類的氧化反應上皆有不錯的催化效果，另外催化劑回收再利用上也得到不錯的成效。In this thesis, we prepared the amide link of polyethylene glycol methyl ether and 2-bromoisobutyryl bromide as the marcoinitiator. We used ATRP method to prepare amphiphilic diblock copolmers with narrow polydispersity. The hydrophilic end of these amphilic block copolymers is polyethylene glycol methyl ether, and the hydrophobic end of these amphilic block copolymers is methyl acrylate. We used EOm-MAn as templates to synthesize porous silica materials under acid aqueous condition. As the hydrophobic end (MA) increases, we can observe the pore size also increasing. When the templates were EO45-MA28, EO45-MA63,EO114-MA113, the cubic and 2-d hexagonal structures, were successfully made.
Moreover, we modified the organic function 3-azido-propylamine on the hydrophobic end, and using the different reaction time to control the modification amount. Using the organic function grafted the Palladium and Tungsten complex on the diblock polymers. Similarly sol-gel process to prepare mesoporous silicas with metal included, which were subjected for catalysis.Suzuki coupling and olefin oxidation by Pd and W respectively, show good activities. For recycle purpose, the catalyst remains activity after 5 run. The metal leach from the porous material was very less in the Tungsten material case.目錄
第一章 緒論……………………………………………………1
1-1孔洞性材料簡介……………………………………………..….1
1-2中孔洞性材料的修飾…………………………………….……..2
1-3中孔洞性材料在催化上的應用………………………………...6
1-4修飾高分子的應用…………………………………………….12
1-5本實驗室之前的研究工作…………………………………….16
1-6本實驗研究目的……………………………………………….17
第二章 兩性共聚物的合成………………………………….18
2-1聚乙二醇甲基醚(polyethylene glycol methyl ether)之末端修飾醯胺化反應………………………………………………………..18
2-2聚丙烯酸甲酯-聚乙二醇甲基醚雙區塊共聚合物(polymethyl acrylate -b-polyethylene glycol methyl ether)……………………..25
2-3聚丙烯酸甲酯-聚乙二醇甲基醚雙區塊共聚合物的修飾(modify on polymethyl acrylate -b-polyethylene glycol methyl ether)……………………………………………………………….30
第三章 以雙區塊共聚物(PEG-N-PMA)為模板進行矽氧孔洞材料的製備…………………………………………………...37
3-1以EO17-N-MAx作為模板…………………………………….37
3-2以EO45-N-MAx作為模板……………………………………..41
3-3以EO114-N-MAx作為模板…………………………………….50
3-4修飾EO45-N-MAx作為模板…………………………………..53
第四章 以雙區塊共聚物(PEG-N-PMA)為模板合成之矽氧孔洞材料在催化上的應用……………………………………...61
4-1矽氧中孔催化劑的鑑定………………………………………61
4-2含鈀金屬的矽氧孔洞材料在催化上的探討…………………63
4-3含鎢金屬的矽氧孔洞材料在催化上的探討…………………67
第五章 結論………………………………………………….74
第六章 實驗部份…………………………………………….75
6-1測試儀器………………………………………………………75
6-2溶劑與試劑的純化……………………………………………79
6-3實驗過程………………………………………………………80
參考文獻……………………………………………………...90
附圖…………………………………………………………...9
sj-pdf-1-imr-10.1177_03000605221100134 - Supplemental material for Clinical outcomes of AngioJet rheolytic thrombectomy in the treatment of May–Thurner syndrome-related deep venous thrombosis
No full textSupplemental material, sj-pdf-1-imr-10.1177_03000605221100134 for Clinical outcomes of AngioJet rheolytic thrombectomy in the treatment of May–Thurner syndrome-related deep venous thrombosis by Wei Wen-Cheng Hsin Chun-Hsien Hsuan-Tzu Yang, Ta-Wei Su, I-Hao Su, Sung-Yu Chu, Po-Jen Ko, Yu Sheng-Yueh Lee Chun-Hui in Journal of International Medical Research</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
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