1,537 research outputs found

    Biodiesel Dari Campuran Lemak Sapi (Beef Tallow) Dan Minyak Sawit

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    Cadangan minyak bumi semakin menipis, sehingga dicari bahan bakar alternatif, salah satunya adalah biodiesel. Minyak nabati terutama minyak sawit merupakan bahan baku edible sedangkan lemak sapi merupakan bahan baku non-edible dengan biaya rendah dan memiliki ketersediaan tinggi pada produksi sapi. Pemanfaatan lemak sapi yang belum maksimal dapat digunakan bersama minyak sawit untuk menghasilkan biodiesel. Lemak sapi dicairkan supaya menjadi minyak sapi. Bahan baku minyak sapi dan minyak sawit dicampur dengan perban-dingan 3:1. Campuran minyak ditransesterifikasi dengan metanol dengan perbandingan molar (1:6) dan katalis NaOH. Proses dilakukan selama 90 menit pada suhu ±65°C. Hasil proses transesterifikasi adalah metil ester dan gliserol. Metil ester pada lapisan atas dipisahkan dari gliserol kemudian dilakukan pencucian. Metil ester atau biodiesel selanjutnya diuji angka asam, viskositas, densitas, dan analisis menggunakan GC-MS. Yield biodiesel yang dihasilkan dari campuran minyak sapi dan minyak sawit adalah 76%, angka asam 0,67124 mg-KOH/g, densitas 857,76 kg/cm³, dan viskositas 3,0074 mm2/s. Kesemua parameter tersebut sesuai dengan standart mutu SNI biodiesel. Kandungan metil ester dari minyak sawit dan lemak sapi adalah metiloleat dan metil palmitat. The availability of the fossil fuel is decreasing; hence the finding of an alternative fuels is very important. One of those alternative fuels is biodiesel. Vegetable oil, especially palm oil is the edible raw material, while the beef tallow is the non-edible raw material with low cost production and the availability is huge in the cattle production. The beef tallow mixed with palm oil can be used as raw material for producing biodiesel. Firstly, the beef tallow was melted into beef oil. The raw materials of beef tallow and palm oil were mixed with the composition ratio of 3:1. The resulted mixed-oil was transesterificated by adding methanol with molar ratio of 1:6 and NaOH as catalyst. The transesterification process was carried for 90 minutes at ±65°C. Transesterification process produces methyl ester and glycerol. The produced methyl ester on the upper layer was separated from the glycerol and then washed. The produced methyl ester was tested to determine the acid number, viscosity, and density. Analysis of the methyl ester components using GC-MS was also conducted. The experimental results show the yield of produced biodiesel from mixed-oil of beef tallow and palm oil (3:1) was 75.93%. The tested acid number, density, and viscosity were 0.67124 mg-KOH/g, 85.76 kg/cm³, and 3.0074 mm2/s, respectively. Data of the tested methyl ester properties are in accordance with the quality of standard ISO for methyl ester. The content of the produced methyl ester from the mixed-oil of beef tallow and palm oil are metiloleat and methyl palmitate

    On Hirschman and log-Sobolev inequalities in mu-deformed Segal-Bargmann analysis

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    We consider a deformation of Segal-Bargmann space and its transform. We study L^p properties of this transform and obtain entropy-entropy inequalities (Hirschman) and entropy-energy inequalities (log-Sobolev) that generalize the corresponding known results in the undeformed theory.Comment: 42 pages, 3 figure

    New Physics searches in a low threshold scintillating argon bubble chamber measuring coherent elastic neutrino-nucleus scattering in reactors

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    The sensitivity to New Physics of a low threshold scintillating argon bubble chamber measuring coherent elastic neutrino-nucleus scattering in reactors is reported. Namely, light scalar mediators, sterile neutrino oscillations, unitarity violation, and non-standard interactions are studied. The results indicate that this detector could be able to set stronger constraints than current limits set by the recent COHERENT measurements. Considering the best scenario, a 100 kg detector located 30 m from a 2000 MWth_{th} reactor, a sterile neutrino search would cover most of the space parameter allowed from the reactor anti-neutrino anomaly fit. Unitarity violation studies could set constraints on α11\alpha_{11} more stringent than the current oscillation experiments fit. A low threshold argon detector with very low backgrounds has the potential to explore New Physics in different scenarios and set competitive constraints

    Carbon and nitrogen mineralization of organic wastes from sugarcane distilleries: vinasse and yeast waste

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    RAMIRAN International ConferenceIn Madeira Island (Portugal) significant amounts of wastes are generated in sugarcane distilleries, namely vinasse (the remaining fermented must after distillation) and yeast waste (the yeast surplus produced during the alcoholic fermentation). These wastes have high organic loads and low pH, leading to serious environmental problems when released directly into natural watercourses or when poorly managed (Hati et al., 2007). As a solution to avoid expensive treatments, both wastes have been used as soil amendment, since they contain important amounts of plant nutrients and organic matter (Resende et al., 2006; Parnaudeau et al., 2008). Indeed, application to soils of vinasse is a common practice in sugarcane cultivated areas and can fully substitute K and partially P on crops fertilization. Nevertheless, additional mineral nitrogen fertilization is needed when vinasse is spread in the soils (Junior et al., 2007; Oliveira et al., 2009). On the other hand, yeast waste has been considered as an excellent potential source of nitrogen for plant nutrition when applied to soils (Rezende et al., 2004). Thus, combined application of both wastes should ensure a more balanced supply of nutrients to plants. However, scarce information is available on the combine use of both wastes as fertilizer. The main objective of this study is to assess the effect of the combined application to soil of both organic materials (vinasse and yeast waste), and to evaluate its subsequent effects on nitrogen mineralization/immobilization process to supply nitrogen to crops and to preserve/restore soil carbon

    Acquired Cytomegalovirus Infection in an Extremely Low-Birth Weight Infant Presenting with a Severe Sepsis-Like Syndrome

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    Cytomegalovirus infection is one of the most common congenital infections worldwide. Moreover, it seems to be an important cause of postnatally acquired infection. Perinatal transmission can occur intrapartum (from the birth canal), from a blood transfusion, via maternal breast milk, or from close contact with infected people. The risk of breast milk-acquired cytomegalovirus infection is higher in countries with a high prevalence of cytomegalovirus immunoglobulin G-positive women. Usually, acquired cytomegalovirus infection is asymptomatic, especially in term infants. However, preterm infants can present with a sepsis-like syndrome and multiple organ involvement. A high index of suspicion is required to make an early diagnosis. Therapeutic guidelines for symptomatic postnatal cytomegalovirus infection are not yet available. More studies are required to understand the long-term sequelae of postnatally acquired cytomegalovirus infection and know which is the best strategy to avoid cytomegalovirus post-natal transmission.info:eu-repo/semantics/publishedVersio

    DNA-barcoding Decapoda and Stomatopoda from West-Africa

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    Codificación del AND de Decápodos y Estomatópodos capturados en Costa Oeste de Áfric

    Optimasi Yield Etil P Metoksisinamat Pada Ekstraksi Oleoresin Kencur (Kaempferia Galanga) Menggunakan Pelarut Etanol

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    Kencur (Kaempferia galanga L.) banyak digunakan sebagai bahan baku obat tradisional (jamu), fitofarmaka, industri kosmetika, industri makanan, dan industri insektisida. Minyak atsiri rimpang kencur mengandung etil sinnamat dan metil p-metoksi sinamat (EPMS). Ekstraksi oleoresin kencur dilakukan dengan etanol sebagai pelarut. Optimasi yield EPMS diteliti terhadap perbandingan massa serbuk kering kencur dan etanol dan waktu ekstraksi. Perbandingan kencur : etanol yang digunakan adalah 1 : 2, 1 : 3, dan 1 : 4. Waktu operasi yang digunakan adalah 2 s.d 5 jam. Tahapan proses ekstraksi oleoresin kencur adalah preparasi bahan, ekstraksi, evaporasi dan pemurnian. Oleoresin hasil ekstraksi dianalisis dengan uji GC-MS untuk mengetahui kandungan EPMS dan kandungan minyak atsiri lain dalam oleoresin kencur. Oleoresin hasil ekstraksi berwarna coklat tua dengan yield antara 6-8%. Kandungan EPMS dalam oleoresin bervariasi antara 67,77 hingga 87,57%. Massa oleoresin optimal hasil ekstraksi adalah 6,09 gram pada perbandingan kencur dan etanol 1:4 selama 4 jam. Pendekatan persamaan hasil ekperimen ekstraksi kencur dan etanol menghasilkan titik optimal EPMS pada waktu ekstraksi 3,62 dengan massa EPMS 6,04 gram Lesser galangal (Kaempferia galanga L.) is widely used as a traditional medicine (herbal medicine), fitofarmaka, cosmetics industry, food industry, and insecticide industry. The essential oils in the Lesser galangal contain ethyl sinnamat and methyl p-methoxy cinnamic (EPMS). The oleoresin extraction of Lesser galangal was performed using ethanol as a solvent. Optimization of the EPMS yield was investigated to dry powder mass ratio of Lesser galangal and ethanol as well as the extraction time. The ratio of Lesser galangal : ethanol was  varied from 1: 2, 1: 3 and 1: 4. The chosen operating time were 2 to 5 hours. The procedure of the oleoresin extraction process of Lesser galangal includes the preparation of materials, extraction, evaporation and purification. The extracted oleoresin was analyzed by GC-MS to determine the content of Ethyl P-methoxycinnamate (EPMS) and other volatile oil content in the oleoresin of Lesser galangal. The extracted oleoresin color was light brown to dark brown with the yield of between 6.31 to 8.3%. The EPMS content of the oleoresin varies between 67.77 to 87.57%. The optimum mass of the extracted oleoresin was 6.09 gram for 1:4 ratio of Lesser galangal : ethanol and 4 hours of the extraction time. The equation approach of the experimental results of Lesser galangal and ethanol produced the EPMS optimum point at the extraction time of 3.62 hours and EPMS mass of 6.04 grams

    Attempts to identify Cassava Brown Streak Virus in western Democratic Republic of Congo

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    Open Access ArticleRoot necrosis similar to those of the cassava brown streak disease (CBSD) were observed on cassava in western provinces of the Democratic Republic of Congo (DR.Congo) in the early 2000’s. However molecular laboratory diagnosis were not able to detect any causative agent responsible for the attacks, hence, the disease related to these symptoms was named CBSD-like disease. In order to assess the distribution and the incidence of the CBSD-like disease, surveys were carried out in four western provinces, comprising, Kwango and Kwilu, Sud Ubangi, Kinshasa and Kongo Central. CBSD-like disease was observed in all surveyed provinces on the basis of root symptoms because foliar symptoms were different to those of the documented cases of CBSD in other parts of east Africa. CBSD-like disease incidence was high in Kongo Central and Sud Ubangi, exceeding an average of 50 %, but low in Kwango and Kwilu (32.8%) and in Kinshasa (19.1%). During the surveys, cassava leaf samples were collected for lab identification of the causal agent. PCR diagnosis was done on these samples using primers specific for the two known CBSVs. All samples tested negative with no amplification of DNA fragments of the correct size. Thus, further analysis on the causative organism is needed using Next Generation Sequencing (NGS) approaches. NGS approaches will help also to identify the causative organism in other Central Africa countries (Angola, Congo-Brazzaville and Gabon) where such cassava root necrosis have been reported or are suspected
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