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ISOLASI DAN KARAKTERISASI STRUKTUR KUMARIN DARI EKTRAK ETIL ASETAT DAUN RENGAS (Gluta renghas L)
Full text linkABSTRACT
ISOLATION AND CHARACTERIZATION COUMARIN STRUCTURE FROM ETHYL ACETATE EXTRACK OF RENGAS LEAVES
By:
Ari Hidayat
*Dr.Suryati *Dr.Afrizal
*Supervisor
Rengas (Gluta renghas L) is one of species plants in indonesia. This plant belonging to the Anacardiaceae family which has an important role in the field of furniture. This species is known by its highly toxic sap coused heavy iritation and skin alergi. In previous study has been reported that Rengas posses 7 secondary compounds isolated like phenol, steroid, coumarine, flavonoid, saponin, and alkaloid. on this study have subjected isolation of coumarin compounds from ethyl asetat extract from Rengas leaves using colomn chromatography methode. Characterization of isolation compounds was carried out using Ultra Violet (UV) and Fourieir Transform infrared (FTIR) spectroscopy. The isolated compound was obtained as a coumarin compound with a melting point of 153-155oC. Further, that UV spectroscopy results show absorption at wavelengths of 200, 204, 225 and 275 nm. While the results of IR spectroscopy showed absorption at wave number 2914, 1700, 1446.69, 1293.19, and 718.09 cm-1.
Keyword : Gluta renghas L, Anacardiaceae , Coumarin, UV, I
IDENTIFIKASI KERUSAKAN COMPRESSOR PADA REFRIGERATOR YANG MENYEBABKAN TIDAK OPTIMALNYA PROSES PENDINGIN BAHAN MAKANAN DENGAN METODE FTA DI MV. ENERGY MIDAS
Full text linkABSTRAKSI
Ari Hidayat, NIT : 49124621.T, 2017 ”Identifikasi Kerusakan Compressor pada
Refrigerator yang Menyebabkan tidak Optimalnya proses Pendingin
Bahan Makanan dengan Metode FTA di MV. Energy Midas”, Program
Diploma IV, Program Studi Teknika, Politeknik Imu Pelayaran Semarang,
Pembimbing I: H. Amad Narto, M. Mar.E, M. Pd, Pembimbing II: Budi
Joko Raharjo, M.M.
Refrigerator adalah suatu rangkaian mesin atau pesawat yang mampu
bekerja untuk menghasilkan suhu atau temperatur dingin (temperatur rendah).
Selain untuk mengawetkan makanan dan sebagai penyejuk udara di dalam
ruangan, mesin pendingin juga memiliki kegunaan-kegunaan lainnya yang lebih
spesifik. Didalam refrigerator terdapat compressor sebuah alat yang berfungsi
untuk menaikkan tekanan refrigerant dan menyalurkan gas refrigerant ke seluruh
system refrigerator. Jika dianalogikan, cara kerja compressor Refrigerator
layaknya seperti jantung di tubuh manusia.
Dalam penulisan skripsi ini penulis mempunyai beberapa rumusan
masalah yang menjadi tujuan penulisan yaitu: Apakah faktor penyebab kerusakan
compressor pada refrigerator yang menyebabkan tidak optimalnya proses
pendingin bahan makanan dan bagaimana cara perawatan compressor pada
refrigerator agar proses pendingin bahan makanan bekerja secara optimal. Sekuat
apapun kontruksi sebuah mesin alat pendingin yang dirancang namun apabila
terjadi kerusakan compressor pada refrigerator akan menyebabkan bahan
makanan tidak segar. Dan tanpa adanya perawatan pelumasan yang rutin pada
semua bagian yang bergerak maka mesin tidak akan bekerja secara maksimal.
Mengingat pentingnya compressor pada refrigerator tersebut harus dirawat
dengan baik. Dalam hal ini penulis menggunakan pendekatan metode fault tree
analysis, dimana metode ini cukup efektif untuk mengetahui akar permasalahan
yang akan diselesaikan. Fault tree analysis adalah model yang memungkinkan
untuk menyorot kombinasi logis dari kesalahan yang dapat menyebabkan
peristiwa utama yang saling berkaitan selanjutnya peristiwa itu disebut top event.
Dari top event kemudian akan merinci dan menjadi sebab-sebab suatu top event
kemudian sampai pada suatu kegagalan dasar (root cause).
Pada kesimpulan dan saran dikemukakan tentang pentingnya perawatan
dan pemeriksaan secara rutin terhadap semua bagian mesin penunjang kinerja dari
Refrigerator demi membuat kinerja mesin menjadi optimal dan agar selalu
melakukan pekerjaan sesuai dengan Intruction Manual book agar dapat mencegah
masalah serupa terjadi dan apabila perusahaan maupun crew kapal sudah mengerti
cara penanganan dari masalah tersebut.
Kata Kunci : Compressor pada Refrigrator, identifikasi kerusakan, Fault tree
analysi
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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