1,720,968 research outputs found
PULPINISASI JERAMI PADA MENGGUNAKAN METODE ORGANOSOLV
Full text linkLaju perkembangan ekonomi dan industri sangat pesat sehingga memicu kebutuhan akan kertas sebagai media informasi secara tertulis. Upaya untuk meminilisasi biaya produksi yang disebabkan oleh kekurangan pasokan bahan baku kayu dan mahalnya harga kayu sudah lama dilakukan. Salah satunya adalah dengan mencari bahan baku alternatif dari bahan lain seperti ampas tebu, pelepah pisang, merang, jerami dan masih banyak lagi. Selain mencari alternatif bahan baku pulp juga dicari proses atau metode pembuatan pulp yang lebih ramah terhadap lingkungan misalnya dengan organosolv (Antaresti, 2003). Di Indonesia salah satu bahan baku pengganti kayu yang dapat digunakan adalah jerami yang banyak terdapat disetiap wilayah atau daerah. Jerami juga banyak terdapat didaerah Jambi, dan biasanya  jerami hanya digunakan sebagai bahan makanan ternak dan dibuat menjadi alternatif atap rumah bambu, padahal jerami masih memiliki nilai ekonomis yang jauh lebih tinggi lagi yaitu dapat dikonversi menjadi pulp (bubur kertas) karena masih mengandung selulosa yang cukup tinggi untuk dapat diolah menjadi pulp, akibatnya jerami akan mempunyai nilai jual yang jauh lebih tinggi dari sebelumnya. Selama ini proses pembuatan pulp menggunakan proses kraft yang tidak ramah terhadap lingkungan jadi dicari proses lain yang lebih ramah terhadap lingkungan, salah satunya proses organosolv. Kelebihan dari proses organosolv diantaranya adalah berdampak kecil bagi lingkungan yaitu tidak menimbulkan pencemaran seperti gas-gas berbau yang disebabkan oleh belerang seperti pada proses kraft, serta cairan pemasaknya lebih mudah untuk dimurnikan kembali (Marzuki, 2005). Berdasarkan uraian diatas, maka dalam penelitian ini dilakukan proses pulpinisasi (proses pembuatan bubur kertas) menggunakan metode organosolv yang lebih ramah lingkungan
PENGGUNAAN METODE EKSTRAKSI PADA PROSES PENGOLAHAN DEDAK PADI (RICE BRAN) MENJADI MINYAK PANGAN
Full text linkRice bran is byproduct result from process of grinder shell of rice become the rice, what is only used as livestock feed. Rice bran basically rich of substance of obstetrical nutrient of fat about 14%. Rice bran can be developed permanent upon which in making of food oil. therefore done by a research. The research use the method extraction use the hexane as a solvent to know the influence of time of extraction and difference of size measure of bran to yielded oil rate. This research is conducted by three types of size measure of bran that is 0,2 mm, 0,6 mm and 1 mm and variation of of time ekstraksi 4,5, and 6 clock. Early stage of research is preparation of raw material in the form of rice bran sieved and deliberated, hereinafter extraction, result of from extraction have to distillation to dissociate the pelarut from oil. Bran oil which obtain; get is later; then analysed by a rate, sour of free fat and peroxide number. Obtained a bran oil of at size measure of bran 0,2 mm and time extraction 6 clock with the oil rate 18,43 %, acid contents free fat 0,9 % and peroxide number 0,9 %.Key Word : rice bran, hexane, distillation, extraction, time, bra
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
Effect Of Hydrothermal Temperature On The Synthesis Of Palm Oil Shell-Based Zeolite: The Synthesis Of Palm Oil Shell-Based Zeolite
No full textPalm oil shells are one of the solid waste in palm oil processing plants, currently the use of palm oil shells is only used as activated charcoal. Though the mineral content potential contained in palm oil shell is very large, one of them is silica (SiO2) of 71.1% with a large amount of this can be used as a source of silica.
The source of silica shell of palm oil in this research is used as the basic material of zeolite manufacture. Zeolite is a hydrated aluminasilicate compound which has many benefits such as catalyst, adsorbent, and ion exchanger. Zeolite fabrication method is a common and widely used hydrothermal method, because this process does not require a high temperature with a relatively short time. Palm oil shells are used to remove carbon in them and the ash is characterised using XRF. Palm oil ash was crushed together with NaOH they were melted at 500°C or 1 hour, and added with distilled water and soaked 24 hours, produced Sodium Silicate and characterised using FTIR. For Alumina, NaOH was reacted with Al(OH)3 to produce Sodium Aluminate and characterised using FTIR. Zeolite preparation was carried out by mixing the sodium silicate and sodium aluminate reactants and the zeolite crystallisation process was carried out using a hydrothermal reactor heated in an oven by varying the hydroternal temperature at 120˚C, 150˚C and 180˚C for 8 hours. Synthesized zeolite was characterised using XRF, XRD and SEM. FTIR analysis Sodium Silicate has been formed at wave number 981.19 cm-1 symmetric vibration Si-O (Na) strectching, and Sodium Aluminate has been formed at wave number 719.87 cm-1 with symmetric vibration Al-O (Na) stretching. The result of XRD characterisation at 120°C produces mixed zeolite of type 4A, Sodalit and Faujasit. At the temperatures of 150°C and 180°C formed Sodalite type zeolite. The best crystallinity was obtained at a hydrothermal temperature of 150°C and analysed using SEM, showing the small cubic crystal form bonding to each other to form an elongated geometry
Pengaruh Penambahan Tempurung Kelapa untuk Meningkatkan Nilai Kalor Biobriket dari Kulit Pisang dan Penggunaan Getah Karet Sebagai Perekat
Full text linkBiobriket merupakan bahan bakar padat yang terbuat dari campuran biomassa, dimana bahan bakar padat tersebut merupakan bahan bakar alternatif yang paling murah dan dapat dikembangkan dalam jumlah besar dalam waktu yang relatif singkat. Tujuan penelitian ini adalah untuk mengetahui variasi komposisi terbaik dalam produksi biobriket dari bahan dasar kulit pisang. Pengujian mutu dan mutu biobriket dilakukan dengan pengujian kadar air, kadar abu, bahan mudah menguap dan nilai kalor. Parameter yang dijadikan acuan mutu sesuai dengan Standar Mutu ISO Nilai Biobriket. Hasil yang didapat adalah biobriket berkualitas dari 12 komposisi yang terdapat pada perlakuan K3 yaitu lilin kulit pisang 100%, dimana kadar air sebesar 0,74%, kadar abu sebesar 8,47%, bahan mudah menguap sebesar 16,04%, dan nilai kalor sebesar 8669,00 Kal/g. Hal ini dikarenakan biobriket pada perlakuan K3 mempunyai sifat karakteristik yang mendekati standar IS
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
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