Studi Experimental Penggunaan Venturi Scrubber Dan Cyclonic Separator Untuk Meningkatkan Kinerja Pada Sistem Exhaust Gas Recirculation (EGR) Dalam Menurunkan NOX Pada Motor Diesel

Salah satu cara yang efektif untuk mengurangi NOX adalah dengan menggunakan metode Exhaust Gas Recirculation (EGR). Dengan metode EGR, oksigen yang masuk ke ruang bakar akan berkurang sehingga NOX dapat diturunkan dengan signifikan, akan tetapi power dari mesin tersebut juga akan berkurang dan Particulate Matter (PM) akan naik secara signifikan. Dalam penelitian ini dibahas penggunaan EGR yang telah di optimalkan dengan penambahan venturi scrubber dan cyclonic separator, tujuannya mengurangi NOX tanpa meningkatkan PM. Hasil pengujian menunjukkan NOX turun sebesar 48.89% dan PM turun dari 69,87% menjadi 9.87%

Analisa Prediksi Potensi Bahan Baku Biodiesel Sebagai Suplemen Bahan Bakar Motor Diesel Di Indoesia

Biodiesel adalah bahan bakar yang terbuat dari bahan yang bersifat dapat diperbarui seperti tumbuh-tumbuhan dan hewan-hewanan. Indonesia adalah negara tropis, dimana memiliki curah hujan yang tinggi dan setiap tahun mendapat sinar matahari. Indonesia memiliki keanekaragaman hayati dan hewani yang tinggi, untuk itu terdapat banyak jenis bahan baku biodiesel yang berpotensi untuk dijadikan suplemen bahan bakar motor diesel di Indonesia. Saat ini jenis bahan baku di Indonesia mencapai lebih dari 50 jenis bahan baku. Metode pemilihan dan analisa bahan baku biodiesel adalah menggunakan metode Analytical Hierarchy Process (AHP). Metode prediksi yang dipakai adalah metode bilangan kuadrat terkecil (Least Square). Dari analisa bahan baku yang sudah dilakukan didapat 6 jenis bahan baku yang berpotensi sebagai suplemen bahan bakar motor diesel di Indonesia yaitu minyak jelantah, kelapa sawit, kelapa, alga, jarak pagar dan karet. Besar potensi produksi minyak biodiesel dari 6 jenis bahan baku biodiesel meliputi jarak pagar 557842 ribu barel minyak biodiesel. Disusul dengan kelapa sawit 438876, alga 258867 ribu barel, kelapa 238455 ribu barel, minyak jelantah 45515 ribu barel, dan karet 3989,7 ribu barel. Dengan adanya suplemen biodiesel, Indonesia akan dapat mengatasi krisis energi sampai pada tahun 2101

Prediksi Performa Linear Engine Bersilinder Tunggal Sistem Pegas Hasil Modifikasi Dari Mesin Konvensional Yamaha RS 100CC

Linear engine adalah salah satu inovasi dari engine yang dikembangkan karena memiliki performa yang lebih baik bila dibandingkan dengan mesin konvensional. Peningkatan performa yang dialami karena berkurangnya gaya gesek yang terjadi. Sehingga perlu dilakukan pembuktian untuk mengetahui performa linear engine hasil modifikasi dari mesin konvensional Yamaha RS 100 CC dengan cara memprediksi melalui simulasi. Dalam analisa ini akan dibandingkan performa mesin konvensional dengan linear engine dalam bentuk perbandingan tekanan dengan volume, daya, torque, BSFC, Brake efficiency dalam variasi kecepatan antara 3.2 m/s – 19.2 m/s. Hasil penelitian menunjukan bahwa performa yang dihasilkan linear engine hasil modifikasi tersebut meningkat. Daya maksimal dari linear engine meningkat sekitar 7.2% dari daya sebelumnya 6.9 kW menjadi 7.4 kW. Begitu juga torque yang dihasilkan meningkat menjadi 12.4 N/m , selain itu BSFC dari linear engine mengalami perbaikan sekitar 2 – 10% dari BSFC sebelumnya

Manufacturing and Installation of the Compound Cryogenic Distribution Line for the Large Hadron Collider

The Large Hadron Collider (LHC) [1] currently under construction at CERN will make use of superconducting magnets operating in superfluid helium below 2 K. A compound cryogenic distribution line (QRL) will feed with helium at different temperatures and pressures the local elementary cooling loops in the cryomagnet strings. Low heat inleak to all temperature levels is essential for the overall LHC cryogenic performance. Following a competitive tendering, CERN adjudicated in 2001 the contract for the series line to Air Liquide (France). This paper recalls the main features of the technical specification and shows the project status. The basic choices and achievements for the industrialization phase of the series production are also presented, as well as the installation issues and status

Memperkuat Islam Moderat Melalui Metode Pembelajaran Demokrasi di Madrasah Ibtidaiyah

This paper aims to promote the implementation of the concept of strengthening moderate Islam through democratic learning in Islamic elementary schools. The ease of internet access and remote communication, as the effect of globalization in the field of technology, can be used to gain any information needed, including the Islamic knowledge that can be freely learned without teachers. A literature study was employed to describe the data related to the internalization of moderate Islam and democratic learning. The findings demonstrate that moderate Islam (tawasuth) is a life principle that upholds justice in social life. The values of moderate Islam can be internalized in the school curriculum as a reinforcement starting from the elementary school level through implementing democratic learning. This application can be carried out through various methods such as discussion, question and answer, group work, and simulation. The implementation of democratic learning encourages communicative relationships between teachers and students, fosters friendship, and enhances the value of ‘ukhuwah’ (good relations). Furthermore, these methods emphasize student-centered learning. This study also illustrates that democratic learning provides a wide array of opportunities for students to creatively and critically express their ideas and thoughts in their own learning styles

The Effect of Blend Fuel Waste Plastic and Waste Cooking Oil on Diesel Engine Performance based on Simulation

Nowadays, polypropylene plastics are very often found and cause various environmental problems. Though it is known that along with polypropylene itself comes from propylene monomers obtained from refining petroleum. Besides the use of waste cooking, biodiesel fuel has many drawbacks, one of which is power and fuel consumption. Mixing polypropylene plastic waste for reuse with waste cooking oil biodiesel is an option. This study uses five variations of fuel, namely HSD, B30, C20, C30, and C40, a combination of HSD, waste cooking, and polypropylene. This research is based on experiments to analyze the impact of using these five variations of fuel on the performance diesel engines based on simulation. The performance of the diesel engine would be measured to SFOC, power, and torque produced by each fuel. Based on the results of the analysis of the performance of the diesel engine performance of C20, fuel can be the most optimum alternative fuel to the substitute B30, producing 6.0 kW of power, 238gr / kWh of SFOC, and 31.7Nm of torque.

Strategies to diagnose ovarian cancer: new evidence from phase 3 of the multicentre international IOTA study

Background: To compare different ultrasound-based international ovarian tumour analysis (IOTA) strategies and risk of malignancy index (RMI) for ovarian cancer diagnosis using a meta-analysis approach of centre-specific data from IOTA3. Methods: This prospective multicentre diagnostic accuracy study included 2403 patients with 1423 benign and 980 malignant adnexal masses from 2009 until 2012. All patients underwent standardised transvaginal ultrasonography. Test performance of RMI, subjective assessment (SA) of ultrasound findings, two IOTA risk models (LR1 and LR2), and strategies involving combinations of IOTA simple rules (SRs), simple descriptors (SDs) and LR2 with and without SA was estimated using a meta-analysis approach. Reference standard was histology after surgery. Results: The areas under the receiver operator characteristic curves of LR1, LR2, SA and RMI were 0.930 (0.917–0.942), 0.918 (0.905–0.930), 0.914 (0.886–0.936) and 0.875 (0.853–0.894). Diagnostic one-step and two-step strategies using LR1, LR2, SR and SD achieved summary estimates for sensitivity 90–96%, specificity 74–79% and diagnostic odds ratio (DOR) 32.8–50.5. Adding SA when IOTA methods yielded equivocal results improved performance (DOR 57.6–75.7). Risk of Malignancy Index had sensitivity 67%, specificity 91% and DOR 17.5. Conclusions: This study shows all IOTA strategies had excellent diagnostic performance in comparison with RMI. The IOTA strategy chosen may be determined by clinical preference

BIOAVAILABILITY STUDY OF ONDANSETRON GEL IN RABBITS AND HUMAN VOLUNTEERS APPLING UPLC AS ANALYTICAL TOOL AND EVALUATION OF THE ANTIEMETIC EFFECT OF ONDANSETRON GEL IN CISPLATIN-INDUCED EMESIS IN RATS

Objective: This study was undertaken to determine the bioavailability of ondansetron gel in experimental animals and humans applying UPLC as an analytical tool and evaluation of the antiemetic effect of ondansetron gel in cisplatin-induced emesis in rats. Methods: Ondansetron gel (F13: sodium alginate 7% w/w) was used, marketed I. V. ondansetron (Zofran) ® was chosen as reference. The bioavailability study in rabbits was selected as a parallel design using nine healthy rabbits divided into three groups whereas, bioavailability study in humans was an open-label, wherein 6 healthy subjects administered ondansetron gel. The potential effect of ondansetron gel was evaluated for the prevention of different phases of emesis motivated by exposure to antineoplastic drugs (cisplatin) by determination of body weight loss, water and food intake applying kaolin-pica model in rats using seventy-two rats divided into six groups. Results: Ondansetron gel (0.5%) showed detectable plasma concentration 22.833±2.17 ng/m1 after ¼ h and 419.55±2.17 ng/ml after 1-h post-treatment in rabbits and human respectively and concentration was maintained above-reported minimum effective concentration for more than 2.5 h for rabbits and 7 h for humans compared to 1.75 h after I. V. administration. The ondansetron gel significantly reduces all phases of cisplatin-induced emesis and a decrease in body weight, water, and food consumption was significantly attenuated. Conclusion: Based on the high efficacy of gel on emesis induced by cisplatin, and its high bioavailability, transdermal ondansetron gel could be a promising convenient system to prevent nausea and vomiting following administration of antineoplastic drugs