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Preparation of Melamine-Formaldehyde Resin Microcapsules Containing Fragrant Oil by Condensation Polymerization
No full text微膠囊具有防止包覆物質揮發、延長其釋放時間以及提高其儲存的穩定性等功能。由於香精油的揮發性相當高，很適合以膠囊化的方式處理後再供進一步的應用。本研究以三聚氰胺和甲醛為壁材，香精油為芯材，使用縮合聚合法製備出香精油微膠囊。研究的目的在製備出粒徑分佈窄且包覆率高的香精油微膠囊。探討的主要變因包括有：溫度、攪拌速率、精油重量比、乳化劑的種類以及乳化劑重量比。由實驗結果得知，微膠囊的平均粒徑會隨著攪拌速率的提升或精油添加量的減少而遞減。其次，由統計軟體Design-Expert 5分析的結果得知，影響微膠囊粒徑的主要因素依其影響程度的大小排列為：乳化劑重量比＞精油重量比＞＞攪拌速率＞溫度，而影響微膠囊包覆率的主要因素依其影響程度的大小排列為：乳化劑重量比＞精油重量比＞＞溫度≒攪拌速率。Microcapsules can prevent the wrapped core materials from evaporating, extend the releasing time and stabilize the core materials during storage. Since fragrant oil has high evaporation property, it is very suitable to be treated by microencapsulation for further applications. In this study, we used melamine and formaldehyde as the shell materials with fragrant oil as the core materials to prepare microcapsules by condensation polymerization method. The purpose of this research is to synthesize the microcapsules containing fragrant oil with narrow size distribution and high capacity. Six factors considered in our experiments include temperature, stirring rate, the mass ratio of fragrant oil, the kinds of emulsifiers, and the mass ratio of emulsifier. It was found that, the higher the stirring rate or the lower the mass ratio of fragrant oil, the smaller the average diameter of microcapsules. In addition, by employing the software of Design-Expert 5 to analyze the experimental data, it was concluded that the degree of the effect of the factors on the particle size of microcapsules follows the order of the mass ratio of emulsifier > the mass ratio of fragrant oil >> stirring rate > temperature, and that on the encapsulating efficiency of microcapsules follows the order of the mass ratio of emulsifier > the mass ratio of fragrant oil >>temperature≒stirring rate.中文摘要………………………………………..………………………...Ⅰ
英文摘要………………………………………………………….………Ⅱ
目錄……………………………………………………..…………...……Ⅲ
圖表目錄………………………………………..……………...…………Ⅴ
第一章 序論……………………………………………………………...1
第二章 原理介紹
2.1 微膠囊簡介………………………………………………............3
2.2 微膠囊的製備方法………………………………………………3
2.3 包覆的原理………………………………………….…………...5
2.4 乳液的形成………………………...……………………..……...6
2.4.1 乳液的不穩定現象………………………………………6
2.4.2 乳化劑……………………………………………………7
2.4.3 乳液的製備方法…………………………………………8
2.5 三聚氰胺甲醛樹脂之合成……………………………………....9
第三章 實驗
3.1 實驗材料與儀器……………………………………………….12
3.1.1 實驗材料…………………………………………………12
3.1.2實驗儀器………………………………………………….12
3.2 實驗步驟……………………………………………………….14
3.2.1 製備包覆香精油的三聚氰胺甲醛樹脂微膠囊…………14
3.2.2 去除未包覆香精油的三聚氰胺甲醛樹脂粒子…………14
3.2.3 觀察微膠囊型態…………………………………………15
3.2.4測量微膠囊粒徑………………………………………….15
3.2.5測量微膠囊包覆率……………………………………….15
3.3 Design-Expert 5介紹…………………………………………..16
第四章 結果與討論
4.1攪拌速率對微膠囊形態與粒徑之影響…………………………17
4.2香精油重量比對微膠囊形態與粒徑之影響…………..……….17
4.3乳化劑種類對微膠囊形態與粒徑之影響….…………………..19
4.4去除未包覆香精油的三聚氰胺甲醛樹脂粒子之討論…………20
4.5攪拌速率、溫度、精油重量比與乳化劑重量比四個變因用Design-Expert 5對微膠囊粒徑與包覆率的討論……..……….21
第五章 結論 …………………………………………………………...24
第六章 參考書目……………………………………………………….25
表目錄
表1. 製備微膠囊的方法………………………………………………...27
表2. 界面活性劑的HLB值與其用途對應關係…………..…................27
表3. 微膠囊粒徑數據…………………………………………………...28
表4. 微膠囊包覆率數據………………………………………………...29
圖目錄
圖2-1 常見微膠囊形狀………………….…...………………………….30
圖2-2 噴霧乾燥法裝置圖……………...………………………………..30
圖2-3 凝膠相分離法流程圖………...…………………………………..31
圖2-4 縮合聚合法流程圖………...……………………………………..32
圖2-5 黏著功示意圖…………...……………………………………..…32
圖2-6 蒸氣凝結法裝置圖…….…………………………………………33
圖2-7 電分散法裝置圖……….…………………………………………34
圖2-8 自然乳化法示意圖………….……………………………………35
圖2-9 乳液不穩定現象示意圖……………………...…………………..36
圖2-10 界面活性劑結構示意圖……………….………………………..36
圖2-11 三聚氰胺與甲醛縮合反應示意圖……...………………………37
圖3-1 雷射光路徑…...………………………………………..................38
圖3-2 微膠囊製備流程圖………...……………………………………..39
圖3-3 測量微膠囊包覆率流程圖……….………………………………40
圖4-1 改變攪拌速率OM(560X)圖 (a) 300 rpm (b) 500 rpm (c) 700 rpm (d) 1000 rpm………………………………………………………………41
圖4-2 改變攪拌速率所製備的微膠囊粒徑分佈圖…………...………..42
圖4-3 改變精油重量比OM(560X)圖 (a) 精油0 wt% (b) 精油1.72 wt% (c) 精油3.44 wt% (d) 精油5.17 wt%…………………………………...43
圖4-4 改變精油重量比所製備的微膠囊粒徑分佈圖………….………44
圖4-5 改變乳化劑種類OM(560X)圖 (a) tween20 (b) tween60 (c) tween81 (d) tween85…………………...…………………………………45
圖4-6 改變乳化劑種類所製備的微膠囊粒徑分佈圖……...………..…46
圖4-7 不同乳化劑製備的微膠囊粒徑比較示意圖………………...…..47
圖4-8 樣品1經離心與過濾處理OM(560X)圖 (a) 原液 (b) 過濾物部份 (c) 過濾液部份 (d) 底部沉澱物部份………………………………48
圖4-9 樣品1經離心與過濾處理的粒徑分怖圖………………...……...49
圖4-10 樣品2經離心與過濾處理OM(560X)圖 (a) 原液 (b) 過濾物部份 (c) 過濾液部份 (d) 底部沉澱物部份………………………………50
圖4-11 樣品2經離心與過濾處理的粒徑分怖圖…….………………...51
圖4-12 OM(420X) (a) 50 °C、300 rpm、精油重量比1.85 wt%、乳化劑重量比1.85 wt% (b) 50 °C、300 rpm、精油重量比7.4 wt%、乳化劑重量比1.85 wt% (c) 80 °C、300 rpm、精油重量比1.85 wt%、乳化劑重量比1.85 wt% (d) 50 °C、300 rpm、精油重量比1.85 wt%、乳化劑重量比11.11 wt%…………………………………………………………………52
圖4-13 OM(420X) (a) 50 °C、1000 rpm、精油重量比1.85 wt%、乳化劑重量比1.85 wt% (b) 80 °C、300 rpm、精油重量比7.4 wt%、乳化劑重量比1.85 wt% (c) 50 °C、300 rpm、精油重量比7.4 wt%、乳化劑重量比11.11 wt% (d) 50 °C、1000 rpm、精油重量比7.4 wt%、乳化劑重量比1.85 wt%……………………………………………………………….53
圖4-14 OM(420X) (a) 80 °C、300 rpm、精油重量比1.85 wt%、乳化劑重量比11.11 wt% (b) 50 °C、1000 rpm、精油重量比1.85 wt%、乳化劑重量比11.11 wt% (c) 80 °C、1000 rpm、精油重量比1.85 wt%、乳化劑重量比1.85 wt% (d) 80 °C、1000 rpm、精油重量比1.85 wt%、乳化劑重量比11.11 wt%………………………………………………………...54
圖4-15 OM(420X) (a) 80 °C、1000 rpm、精油重量比7.4 wt%、乳化劑重量比1.85 wt% (b) 50°C、1000rpm、精油重量比7.4 wt%、乳化劑重量比11.11 wt% (c) 80 °C、300 rpm、精油重量比7.4 wt%、乳化劑重量比11.11 wt% (d) 80 °C、1000 rpm、精油重量比7.4 wt%、乳化劑重量比11.11 wt%…………………………………………………………...55
圖4-16 微膠囊粒徑Half Normal plot……………….…………………..56
圖4-17 微膠囊粒徑 Outlier plot…….………………………………...57
圖4-18 微膠囊粒徑Interaction graph (A) Interaction of 溫度與攪拌速率 (B) Interaction of 溫度與精油重量比……..…………………………….58
圖4-19 微膠囊粒徑Interaction graph (A) Interaction of 溫度與乳化劑重量比 (B) Interaction of 攪拌速率與精油重量比……………………….59
圖4-20 微膠囊粒徑Interaction graph (A) Interaction of 攪拌速率與乳化劑重量比 (B) Interaction of 精油重量比與乳化劑重量比…………….60
圖4-21 微膠囊包覆率Half Normal plot…………….…………………..61
圖4-22 微膠囊包覆率 Outlier plot………..…………………………….62
圖4-23 微膠囊包覆率Interaction graph (A) Interaction of 溫度與攪拌速率 (B) Interaction of 溫度與精油重量比……………………………….63
圖4-24 微膠囊粒徑Interaction graph (A) Interaction of 溫度與乳化劑重量比 (B) Interaction of 攪拌速率與精油重量比……………………….64
圖4-25 微膠囊包覆率Interaction graph (A) Interaction of 攪拌速率與乳化劑重量比 (B) Interaction of精油重量比與乳化劑重量比…………..6
The decompositions with respect to two core non-symmetric cones
No full textIt is known that the analysis to tackle with non-symmetric cone optimization is quite different from the way to deal with symmetric cone optimization due to the discrepancy between these types of cones. However, there are still common concepts for both optimization problems, for example, the decomposition with respect to the given cone, smooth and nonsmooth analysis for the associated conic function, conic-convexity, conic-monotonicity and etc. In this paper, motivated by Chares’s thesis (Cones and interior-point algorithms for structured convex optimization involving powers and exponentials, 2009), we consider the decomposition issue of two core non-symmetric cones, in which two types of decomposition formulae will be proposed, one is adapted from the well-known Moreau decomposition theorem and the other follows from geometry properties of the given cones. As a byproduct, we also establish the conic functions of these cones and generalize the power cone case to its high-dimensional counterpart
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
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