1,721,065 research outputs found
Pengaruh Alkalisasi Terhadap Kekuatan Tarik Dan Impak Pada Komposit Epoxy Berpenguat Serat Daun Nanas
Full text linkPengembangan teknologi komposit serat alam dan limbah pertanian perkebunan dapat membantu mengatasi kelangkaan bahan baku industri otomotif dan dapat mencegah kerusakan lingkungan (Supriyatna, 2018). Dalam penelitian ini menggunakan Polymer matrix composites (PMC) yang merupakan komposit yang bahan dan matriksnya terdiri dari polimer resin. Serat alam digunakan dalam penelitian sebagai material penguat dalam komposit polimer karena mempunyai sifat mudah terurai.
Penelitian ini menggunakan reinforce serat daun nanas yang di beri perlakuan alkalisasi dengan parameter bebas variasi alkalisator (NaOH) 3%, 5% dan 7% dan lama waktu perendaman dalam alkali sebesar 2jam, 4jam dan 6 jam. Parameter terikat dengan perbandingan resin epoxy dan hardener sebesar 2:1, campuran komposit dengan fraksi massa resin dan reinforce sebesar 98% : 2%. Setelah perlakuan alkalisasi serat daun nanas diamati dengan scanning electron microscope (SEM) untuk mengetahui struktur serat sebelum perlakuan alkalisasi dan sesudah alkalisasi.
Hasil penelitian untuk pengamatan SEM menyatakan bahwa serat sebelum alkalisasi terdapat lignin pada permukaan serat dan setelah perlakuan alkalisasi tampak kekasaran permukaan serat karena larutnya lignin pada proses alkalisasi. Hasil pengujian tarik komposit serat daun nanas tanpa perlakuan alkalisasi mendapatkan kekuatan sebesar 38.98 MPa dan kekuatan optimum berada pada variasi 5% selama 2jam dengan kekuatan sebesar 53.68 MPa. Hasil pengujian impak komposit serat daun nanas menunjukan kekuatan optimum berada pada variasi alkalisasi 5% selama 2jam dengan rata-rata kekuatan impak sebesar 149.75 kJ/mm2
Penentuan Umur Simpan Yoghurt Kacang Hijau (Phaeseolus radiatus, Linn).
No full textMungbean include one of food plant that has been widely recognized by society, even the plants that belonging to the family of pulses has been long cultivated. In Indonesia, mungbean plant is the third-crop beans that are largely grown after soybean and peanuts. Because of its relatively high protein content and the price is relatively cheap, mungbean have a good prospect as a nutritious food that can be consumed by the public, so it is appropriate to be developed in order to increase their economic value. One alternative forms of processing, is to make yogurt from mungbean. However, the short shelf life of yogurt is sometimes become an obstacle, its because the ignoranced consumer about the storage of yogurt. To ensure that the yogurt is still worthy to consumed and not damaged, you need information about shelf life. This study aims to determine shelf life of mungbean yogurt and measuring the decline in the quality of yogurt during storage. This research was conducted with storing mungbean yogurt in the three different temperatures, that is 5 oC, 15 oC and 25 oC. And packaged in three different packaging, that is glass bottles, HDPE and PP. To determine the shelf life of mungbean yogurt, it use Extended Storage Studies (ESS) or the conventional method of determining the expiration date with in the way to save a product at normal conditions of daily and observed for its decrease quality until it reaches the quality level shelf. Quality parameters were analyzed during storage of yogurt that is fat content, protein content, pH, total acid, and the presence of coliform bacteria. The results for the initial characterization showed that the yogurt product having 4.06 in pH; total acid of 1.90%, 0.15% fat content, protein content of 7.85%, and negative values to test the presence of coliform bacteria. During the storage period there was a change of pH, total acid, fat and protein content, and presence of coliform bacteria. Critical parameters of shelf life of mungbean yogurt is the presence of coliform bacteria and total acid. Based on this research, for total acid as a critical parameters during storage, obtained that shelf life of mungbean yogurt is 21 days for yogurts that stored at 5 °C in glass bottle, HDPE and PP. Then, 18 days for yogurt that is stored on temperature of 15 oC in the packaging of HDPE, and 21 days for yogurt that packed with glass and PP packaging materials. Whereas, yogurt that stored at a temperature of 25 oC, has the shortest shelf life, its just six days for the products that are packed with every type of packaging, that are glass, HDPE and PP. For existence of coliform bacteria as a critical parameters, during storage at 5 °C, the yogurt that was not safe again to eat because of the presence of bacterial, is yogurt that packed with HDPE. For the yogurt that stored at a temperature of 15 oC, which already exceeds the safe limit of SNI is yogurt that packed with HDPE and PP. While, yogurt that stored at a temperature of 25 oC, there is no product that exceeds the safe limits of the presence of coliform bacterial from SNI
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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