1,720,993 research outputs found
Acidogenic Fermentation of Palm Oil Mill efluent (POME) on Volatile Fatty Acids production as Precursor
Get PDFAcidogenic fermentation of palm oil mill efluent (POME) can serve as a precursor in a process for production of
polyhydroxyalkanoates (PHA) since the produced volatile fatty acids (VFAs) are preferred precursor for PHA production.
Acidogenic fermentation of POME was studied in a 2-L reactor with semi-continuous mode operation (once-a-day feeding and
draw-off) for optimal volatile acid compositions. Main fermentation products were acetic acid, propionic acid and butyric acid. The results showed acetic acid, propionic acid, and butyric acid with concentrations are 2.79 g/L; 1.18 g/L, and 3.04 g/L,
respectively. VFAs that serves as a precursor on PHA production. The result of feeding of synthetic of VFAs or VFAs from POME at the 20th and 40th in a batch show the concentrations DCW and PHA are 2.38 g/L and 0.74 (g PHA/g DCW) or 2.76 g/L and 0.74 (g PHA/g DCW), respectively
RANCANG BANGUN ALAT VACUUM DRYING DALAM PROSES PEMBUATAN TEPUNG MORINGA OLEIFERA LAMK
Get PDFMoringa oleifera lamk are trees with a height of up to 12m with a diameter of 30cm. The wood is a type of soft wood and has a low quality. And has many benefits, one of which is food, health, beauty and the environment.The working principle of this spinner type dryer is the material in the form of Moringa leaves frozen first using the freezer and then put into the dryer and dispatched the time that has been adjusted together with the hot air blower so that the drying process can take place quickly, after dispensing the Moringa leaves vacuum by using a vacuum pump to remove the water contained in the material so that the leaves of moringa are completely dry, the process continues until the leaves are completely dry and ready to be made flour, The variations carried out during the drying process take place are temperature and drying time so that it is known what water content and final weight of the Moringa leaf after drying. Vacuum drying appliance has been designed with the specification tool dimensions namely: 0.0020258m2 sectional area of the intake air, the rotation speed of 750rpm, power needed for 154watt, length 220mm V-belts V-belts with a speed of 3.925m/s. Produce Moringa leaf powder with a moisture content of 15% with the quality of green products (Moringa leaves), the fineness of the flour in accordance with the Indonesian National Standard quality of the flour (80mesh sieve), and the content of protein content is high at 28.84%
PRODUCTION BIOMETHANE FROM PALM OIL MILL EFFLUENT (POME) WITH TRUNCATED PYRAMID DIGESTER IN FED BATCH SYSTEM
Get PDFPalm oil mill effluent (POME) production in Indonesia is estimated around 63
million ton/year [1]. Therefore it is a potential source of contamination when it directly
discharged into the river. Even though, POME will be as raw resource biogas production.The
aims of this research were to know the effect of fermentation time toward biogas production in
truncated pyramid digester. The study was done in three combinations of feedstock with
POME concentrations of 90, 80, and 70% and activated sludge concentrations of 10, 20, and
30%. A mixture of POME and activated sludge at 6 L/minutes for 30 days were fed into the
digester. The result showed the fermentation time gave significant effect toward biogas
production in the truncated pyramid digester. All combinations showed the upward trend in the
volume of biogas during fermentation. The highest quantity of biomethane in biogas was 25%
mol that the active microbes were added to POME in the ratio 1: 9 in a fed-batch system
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
PRODUKSI BIOGAS DARI AIR LIMBAH INDUSTRI MINYAK KELAPA SAWIT MENGGUNAKAN DIGESTER ANAEROBIK MODIFIKASI DENGAN PENAMBAHAN PENGADUKAN
Get PDFBiogas produced from Palm Oil Mill Effluent (POME) can provide several benefits for the environment, such as can reduce environmental pollution and produce new energy sources. The purpose of this research was to determine the ratio of methane was producedfrom batch and fed bacth processes, and to determine the optimal agitation speed for biogas formation from POME as the main ingredient and cow dung as starter. This research used ratio 50:50 of POME:starter and variations of agitation speed are 95 rpm and 100 rpm.Biogas was formed will be taken on days 4th, 8th, 12th, and 16th. The highest yield of biogas by fed batch system was on day 16th with 100 rpm agitation speed produced methane of 9,67%. While the lowest result was on day 4th at 95 rpm agitation speed with 0%. For batch system, thehighest yield of biogas was produced on day 16th at 100 rpm with 7,927%. And the lowest yield was on day 4th at 95 rpm agitation speed with 0,93%. From this reserach, it can be concluded that fed batch system can produce higher methane from the result of the anaerobic fermentation process of POME than batch system. In addition, a higher agitation speed will also produce higher amount of methan
EFFECT OF GLUCOSE AND FRUCTOSE ON PRODUCTION POLYHYDROXYALKANOATES BY Ralstonia eutropha JMP 134 AS BATCH FERMENTATION
Get PDFPolyhydroxyalknoate (PHA) is a bioplastic from the group of polyester with physicochemical properties similar to polypropylene plastic from petroleum. This research aims to study the effect of glucose and fructose on PHA fermentation process performed by using Ralstonia eutropha JMP 134 in a batch bioreactor. Dynamics of PHA production from carbon sources glucose or fructose, as well as the influence of volatile fatty acids as a prekursor were studied in this research.  Fermentation operating condition using bioreactor 10 L maintained at a temperature of 30oC and pH of 7.  The concentration of carbon source used was 40 g/L, and after 20th hours of fermentation added volatile fatty acids (VFAs) that serves as a prekursor in the production of PHA. Aerobic fermentation of Ralstonia eutropha JMP 134 with the substrate glucose and fructose using synthetic VFAs produce PHA content of each were 0.21 and 0.33 g PHA/g dry cell weight (DCW). The percentage composition PHA of glucose or fructose with synthetic ALV are 8.71% or 11.78% HV, respectively. So Ralstonia eutropha JMP 134 fermentation using fructose substrate provides a higher PHA content than using glucose substrate
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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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