1,014 research outputs found

    The Anharmonic Correction in the Soliton Model for the Hyperons

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    We derive the anharmonic correction to the hyperon energy in the bound state version of the topological soliton model for the hyperons, and show that it represents a negative correction of at most 10% to the energy of the bound heavy flavour two-meson system in the case of cascade hyperons. The main anharmonic correction arises from the mass term in the Lagrangian density. For large meson masses the consistency of the model requires that the anharmonic correction decreases as the inverse square root of the mass of the heavy flavour meson.Comment: 19 page

    A monitored beam for precise neutrino flux determination: The ENUBET project

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    In this paper we discuss the ENUBET experiment and explain how it can reduce by nearly one order of magnitude the flux-related systematics in accelerator neutrino beams. The ongoing research and development activities are described, together with the latest testbeam results from detector prototypes

    Struktur Dan Komponen Arang Serta Arang Aktif Tempurung Kemiri

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    Cara aktivasi arang menentukan kekhususan penggunaan arang aktif yang dihasilkan. Secara umum dikenal dua cara aktivasi arang untuk menghasilkan arang aktif yaitu cara fisika dan kimia. Penelitian ini bertujuan untuk mengetahui struktur dan komponen penyusun arang dan arang aktif tempurung kemiri. Tempurung kemiri dikarbonisasi menggunakan tungku drum untuk menghasilkan arang, selanjutnya arang diaktivasi di dalam retort listrik menggunakan aktivator panas selama 120 menit pada suhu 550C, 650C, dan 750C dan aktivator uap air selama 90 dan 120 menit pada suhu 750C. Sampel uji tempurung kemiri, arang dan arang aktif dikarakterisasi strukturnya yang meliputi gugus fungsi, kristalinitas dan porositas dengan menggunakan Fourier Transform Infra Red (FTIR), X-Ray Difractometer (XRD) dan Scanning Electron Microscope (SEM). Selain itu, senyawa kimia masing-masing sampel uji diidentifikasi menggunakan Pyrolisis Gas Chromatograph Mass Spectrometer (Py-GCMS) Hasil mengindikasikan bahwa proses aktivasi menyebabkan terjadinya Perubahan pola gugus fungsi, peningkatan kristalinitas, pembukaan pori dan reduksi senyawa kimia. Semakin tinggi suhu aktivasi diikuti oleh peningkatan kristalinitas, diameter pori dan reduksi senyawa kimia arang aktif. Aktivasi menggunakan uap air menghasilkan arang aktif dengan pori yang relatif lebih bersih

    Integration of SRF and carbonization plant for small forestry farms

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    A continuous oxidative carbonization pilot unit, with a capacity of 50 kg/h,has been developed and builtby RE-CORD; reported performance data shows that the unit can produce high quality charcoal, suitable for BBQ, metallurgy of activated-carbon manufacturing, as well as biochar. Charcoal yield in excess of 24 wt% (dry) has been achieved, with a fixed carbon content higher than 85 wt% (dry). In this work,the up-scaled 250 kg/h demo plant has been designed, and the construction, operation and maintenancecosts estimated. It was assumed to feed the plant with a dedicated SRF of either poplar or robinia, which represents a very innovative and yet unexplored value chain. Performance data are reported along with economic evaluation of the whole chain. Results shows how aland management scheme based on SRF coupled to innovative small-scale biomass carbonization technology represents an appealing opportunity for business diversification in small and medium forestry enterprises

    Transoral endoscopic thyroidectomy: A case report

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    AbstractIntroductionEndoscopic thyroidectomy, initially an experimental procedure, is now being performed in increasing frequency. It aims to provide patients undergoing thyroidectomy with a ‘scar-free’ surgery. Transoral endoscopic thyroidectomy is one such novel procedure that is based on the principles of natural orifice translumenal surgery (NOTES) and allows for a truly scar-free surgery with minimal dissection.Presentation of caseA 21-year-old female presented with a swelling over the left side of her neck. Ultrasound revealed a solitary nodule and FNAC showed features suggestive of a follicular adenoma.DiscussionThe patient underwent transoral endoscopic hemi-thyroidectomy. The procedure lasted for 2h and is one of the few documented cases of transoral endoscopic thyroidectomy performed on live patients.ConclusionTransoral endoscopic thyroidectomy is proving to be a feasible technique with little or no complications as compared to other endoscopic thyroid surgeries. It provides surgeons with easy access to the thyroid gland and patients with aesthetically pleasing results

    Effect of Gymnema montanum Leaves on Serum and Tissue Lipids in Alloxan Diabetic Rats

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    The effect of Gymnema montanum leaves on alloxaninduced hyperlipidemia was studied in male Wistar rats. Ethanolic extract of G. montanum leaves was administered orally and different doses of the extract on blood glucose, serum and tissue lipids, hexokinase, glucose-6-phosphatase, thiobarbituric acid–reactive substances (TBARS), hydroperoxides, and glutathione in alloxan-induced diabetic rats were studied. G. montanum leaf extract (GLEt) at doses of 50, 100, 200 mg/kg body weight for 3 weeks suppressed the elevated blood glucose and lipid levels in diabetic rats. GLEt at 200 mg/kg body weight was found to be comparable to glibenclamide, a reference drug. These data indicate that G. montanum represents an effective antihyperglycemic and antihyperlipidemic adjunct for the treatment of diabetes and a potential source of discovery of new orally active agent for future therapy

    Characterization of Activated Carbon Produced From Urban Organic Waste

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    The difficulties to decompose organic waste can be handled naturally by pyrolisis so it can decomposes quickly that produces charcoal as the product. This study aims to investigate the characteristics of activated carbon from urban organic waste. Charcoal results of pyrolysis of organic waste activated with KOH 1.0 M at a temperature of 700 and 800oC for 60 to 120 minutes. Characteristics of activated carbon were identified by Furrier Transform Infra Red (FTIR), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). However, their quality is determined yield, moisture content, ash, fly substances, fixed carbon, and the power of adsorption of iodine and benzene. The identified functional groups on activated carbon, such as OH (3448,5-3436,9 cm-1), and C=O (1639,4 cm-1). In general, the degree and distance between the layers of active carbon crystallites produced activation in all treatments showed no significant difference. The pattern of activated carbon surface topography structure shows that the greater the pore formation in accordance with the temperature increase the more activation time needed. The yield of activated carbon obtained ranged from 72.04 to 82.75%. The results of characterization properties of activated carbon was obtained from 1.11 to 5.41% water, 13.68 to 17.27% substance fly, 20.36 to 26.59% ash, and 56.14 to 62.31% of fixed carbon . Absorption of activated carbon was good enough at 800oC and 120 minutes of activation time, that was equal to 409.52 mg/g of iodine and 14.03% of benzene. Activated carbon produced has less good quality, because only the water content and flying substances that meet the standards.Doi: 10.12777/ijse.5.2.89-94 [How to cite this article: Haji, A.G., Pari, G., Nazar, M., and Habibati. (2013). Characterization of activated carbon produced from urban organic waste . International Journal of Science and Engineering, 5(2),89-94. Doi: 10.12777/ijse.5.2.89-94

    Arang Aktif Serbuk Gergaji Kayu sebagai Bahan Adsorben pada Pemurnian Minyak Goreng Bekas

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    Tulisan ini mengemukakan hasil penelitian pembuatan arang aktif dari serbuk gergaji kayu dengan proses aktivasi kombinasi antara cara kimia dan fisika. Tujuan dari penelitian ini adalah untuk mengetahui 1) Pengaruh konsentrasi asam fosfat sebagai bahan pengaktif kimia, 2) Pengaruh suhu dan lama waktu aktivasi terhadap mutu arang aktif dan 3) Pengaruh penambahan arang aktif terhadap mutu minyak goreng bekas. Sebelum dibuat arang aktif, terlebih dahulu serbuk gergaji kayu dibuat arang dengan menggunakan tungku semi kontinyu pada suhu 300OC. Arang yang dihasilkan selanjutnya direndam dalam larutan asam fosfat dengan konsentrasi 5,0 dan 10% selama 24 jam. Proses aktivasi dilakukan di dalam retort yang terbuat dari besi tahan karat pada suhu 800, 850, 900OC dengan lama waktu aktivasi masing-masing 30, 60 dan 90 menit. Dalam penelitian ini digunakan larutan (NH4)2CO30,20% sebagai gas pengoksid.Hasil penelitian menunjukkan bahwa kualitas arang aktif serbuk gergaji kayu yang terbaik adalah arang aktif yang direndam asam fosfat 5% pada suhu 900oC selama 30 menit. Pada proses aktivasi tersebut diperoleh rendemen arang aktif sebesar 72,71%, dan arang aktif yang dihasilkan mengandung kadar air 4,23%, kadar zat terbang 5,84%, kadar abu 42,53%, kadar karbon terikat 52,25%, daya serap terhadap kloroform 24,86%, benzena 16,97% dan daya serap terhadap yodium sebesar 668,63 mg/g. Nilai daya serap ini memenuhi syarat Standar Amerika dan arang aktif yang dihasilkan permukaannya lebih bersifat polar sehingga dapat digunakan untuk menyerap polutan yang juga bersifat polar seperti aldehida. Kualitas minyak goreng bekas menjadi lebih baik setelah ditambahkan dengan arang aktif sebanyak 2,5% yang ditunjukkan dengan menurunnya kandungan asam lemak bebas dan bilangan peroksida masing-masing dari 0,27% menjadi 0,17% dan dari 18,87 menjadi 10,96 meq O2/kg. Sedangkan untuk kecerahan warna mengalami peningkatan dari 13,98 menjadi 16,02%. Mutu minyak goreng ini terutama asam lemak bebas dan bilangan perokisda memenuhi syarat minyak goreng yang ditetapkan SNI
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