1,720,960 research outputs found
Influence of monomer concentration on the morphology, contact angle, water uptake, and antibacterial activity of grafted cellulose obtained from peel durian
Full text linkThe objective of the current study is to evaluate and determine the effect of monomer concentration of ClAETA on the grafting copolymerization of oxidized cellulose which isolated from peel durian. Four concentrations of ClAETA were used in this study, e.g., 40, 50, 60, and 70%. Several analyses were performed to determine the material characteristic, e.g., degree of grafting, FT-IR, surface morphology, contact angle, degree of swelling, and antibacterial activity. The result showed, monomer concetration plays a significant role to the physical and surface morphology of DAC-ClAETA. The degree of grafting of ClAETA was found in the range of 15-31%, and at the concentration of 50% the grafted oxidized cellulose has 30.4% of degree of grafting. SEM images showed the pore volume has linear correlation to the monomer concetration, it increased the surface roughness. Also, the contact angle confirmed the hydrophilicity and degree of swelling of grafted oxidized cellulose was increase that linear to ClAETA concentration. DAC-g- ClAETA was found antibacterial active against S. aureus, S. epidermis, and C. albicans than DAC
Preparation and characterization of physical properties of molded pulp from empty fruit bunches of oil palm
Full text linkThis research aims to determine the impact of pretreatment on empty fruit bunches (EFB) of palm oil fibers before the pulping process on the quality of the molded pulp produced. The study includes EFB fiber pretreatment processes, pulp production, pulp molding, physical characteristic analysis, and molded pulp performance evaluation. The pulp production process involves acid-base hydrolysis reactions. The produced molded pulp is done manually. Characterization of the molded pulp includes measurements of paper grammage, thickness, density, and moisture content. The characteristics of pulp produced from pretreated EFB fibers are as follows: an average grammage value of 415.48 g/m, paper thickness of 1.53 mm, water absorption capacity of 13.33-33.33%, density of paper of 0,026 x 106 - 0,027 x 106 g/m3, and a smooth surface morphology. Meanwhile, the characteristics of pulp produced from without pretreatment EFB fibers include an average grammage value of 372.18 g/m, paper thickness of 0.77 mm, water absorption capacity of 20.34-43.21%, density of paper of 0,004 x 106 - 0,008 x 106 g/m3, and a rough surface morphology due to pores on the fiber surface
Phytochemichal identification of Gayo tobacco or bakong Gayo (Nicotiana tabacum L) and its potency for industrial applications
Full text linkAbstract: This research aims to identify the phytochemical content of Gayo tobacco or Bakong Gayo (Nicotiana tabacum L) using Gas Chromatography Mass Spectrometry (GCMS) and its potential application in industry. Gayo tobacco was extracted using methanol solvent and characterized by GCMS using mode selection ion monitoring (SIM) which obtained twelve phytochemical contents in Gayo tobacco, were alkaloid, terpenoids, fatty acids and carbocyclic acid with the main compound being nicotine (40.58 %) and 4,8,13-duvatriene-1,3-diol (31.10 %). The twelve compounds identified can be applied as anticancer, insecticide, anti-depressant, sedative, anti-corrosion, aromatherapy and others based on the theory . All phytochemical compounds in Gayo tobacco allow it to be developed in the pharmaceutical and cosmetic industries.Abstrak: Penelitian ini bertujuan mengidentifikasi kandungan fitokimia tembakau Gayo atau bakong Gayo (Nicotiana tabacum L) menggunakan Gas Chromatography Mass Spectrometry (GCMS) dan potensi apilkasinya diindustri. Tembakau Gayo diekstraksi dengan pelarut metanol dan ekstrak daun tembakau Gayo dikarakterisasi GCMS dengan menggunakan mode selected ion monitoring (SIM) diperoleh dua belas kandungan fitokimia dalam tembakau Gayo yaitu jenis alkaloid, terpenoid, asam lemak dan asam karbosiklik dengan senyawa utama yaitu nikotin sebesar 40,58% dan 4,8,13-Duvatriene-1,3-Diol sebesar 31,10 %. Kedua belas senyawa-senyawa yang diidentifikasi menurut teori dapat diaplikasi sebagai antikanker, insektisida, anti depresant, obat penenang, anti korosi, aromaterafi dan lain-lain. Semua senyawa fitokimia dalam tembakau Gayo memungkinkan untuk dikembangkan dalam bidang industri obat dan kosmetika
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
- …
