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"Elektroda Boron-Doped Diamond termodifikasi core-shell nanopartikel AuPd telah berhasil dipreparasi dengan cara perendaman BDD terminasi N dalam koloid nanopartikel AuPd. Lapisan shell Pd NP terbentuk pada core nanpartikel Au dari hasil reduksi larutan HAuCl4 dengan variasi penambahan H2PdCl4 1,0 mM dan asam askorbat. Spektrum UV-Vis dari nanopartikel Au menunjukkan panjang gelombang maksimum pada ? = 523 nm yang diikuti dengan penurunan absorbansi AuPd NP seiring pembentukan nanopartikel palladium. Karakterisasi nanopartikel menggunakan Transmission Electron Microscopy TEM menunjukkan bahwa core-shell AuPd NP memiliki bentuk flower shape dengan diameter Au NP sebesar 14,26 nm dan ketebalan Pd NP masing-masing 6,91 nm dan 4,05 nm. AuPd NP yang dideposisi ke permukaan elektroda BDD-N dikarakterisasi menggunakan Scanning Electron Microscopy Energy Dispersive X-Ray SEM-EDX dan X-Ray Photoelectron Spectroscopy XPS. Penentuan kadar oksigen dilakukan menggunakan teknik siklik voltammetri dalam larutan buffer fosfat PBS dengan variasi lamanya waktu aerasi oksigen yang diukur menggunakan DO meter. Hasil pengukuran menujukkan bahwa kemampuan pemisahan sinyal arus terhadap background pada elektroda BDDN-AuPdNP 1 S/B = 2,82 lebih baik dibandingkan BDDN-AuNP S/B = 2,59 dan BDDN-AuPdNP 2 S/B = 1,12 . Pembentukan Pd NP pada permukaan Au NP mempengaruhi sensitifitas pada elektroda sehingga modifikasi elektroda BDD-N dengan nanopartikel AuPd diharapkan dapat menghasilkan elektroda yang lebih sensitif untuk pengukuran oksigen dan dapat dikembangkan selanjutnya untuk penentuan BOD dalam air.

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Core shell nanoparticle Au Pd modified Boron Doped Diamond electrode has been succesfully prepared by immersion of BDD terminating N in Au Pd colloid nanoparticles. The Pd shell layer was formed on Au nanoparticle cores from the reduction of HAuCl4 solution with variations of 1.0 mM H2PdCl4 volume addition and ascorbic acid. UV Vis spectra of Au nanoparticles showed the maximum wavelength was obtained at 523 nm which followed by the decreasing of absorbance of AuPdNP as the formation of Pd shell. Characterization of nanoparticles using Transmission Electron Microscopy TEM shows that the AuPd Np core shell has a flower like shape with 14.26 nm of AuNP core diameter and PdNP shell thickness of 6.91 nm and 4.05 nm, respectively. The AuPd NPs were deposited on BDD N surface and were characterized using Scanning Electron Microscopy Energy Dispersive X Ray SEM EDX and X Ray Photoelectron Spectroscopy XPS. Determination of oxygen level was carried out using cyclic voltammetry in phosphate buffer solution PBS at various oxygen aeration time where its concentration was measured using DO meter. The results show that BDDN AuPdNP 1 had a better current to background signaling capability S B 2.82 than BDDN AuNP S B 2.59 and BDDN AuPdNP 2 S B 1.12 . It is belived that the formation of Pd shell on the surface of Au NP affects the sensitivity of the electrode. As the result, modification of BDD N electrodes with Au Pd nanoparticles are expected to produce more sensitive electrodes for oxygen measurements which can be further developed for Determination of BOD in the water."

"In this research, a layered-recurrent artificial neural network (ANN) using the back-propagation method was developed for simulation of a fixed-bed industrial catalytic reforming unit called Platformer. Ninety-seven data points were gathered from the industrial catalytic naphtha reforming plant during the complete life cycle of the catalytic bed (about 919 days). Ultimately, 80% of them were selected as past horizontal data sets, and the others were selected as future horizontal ones. After training, testing, and validating the model with past horizontal data, the developed network was applied to predict the volume flow rate and research octane number (RON) of the future horizontal data versus days on stream. Results show that the developed ANN was capable of predicting the volume flow rate and RON of the gasoline for the future horizontal data sets with AAD% (average absolute deviation) of 0.238% and 0.813%, respectively. Moreover, the AAD% of the predicted octane barrel levels against the actual values was 1.447%, which shows the excellent capability of the model to simulate the behavior of the target catalytic reforming plant."

"Pada skripsi ini berisi tentang beberapa langkah percobaan yang dilakukan dalam melakukan proses investigasi terhadap transformator distribusi 3 fasa 630 kVA milik PT PLN (Persero) Distribusi Jakarta Raya dan Tangerang. Berdasarkan hasil pemeriksaan secara visual terhadap objek, teridentifikasi bahwa kerusakan terjadi pada daerah tap changer. Percobaan yang dilakukan meliputi beberapa aspek yang diduga menjadi penyebab terjadinya kerusakan. Adapun percobaan/pengujian yang dilakukan meliputi: pengujian Dissolved Gas Analysis (DGA), pemeriksaan design trafo, pengujian tegangan terapan/applied voltage, pengukuran tahanan isolasi/megger, pemeriksaan korosi belerang, pengujian tegangan tembus/Break Down Voltage (BDV). Berdasarkan pengujian yang dilakukan, diperoleh hasil sebagai berikut: Hasil pengujian Dissolved Gas Analysis untuk trafo rusak berada pada kondisi 4; Hasil pemeriksaan design trafo diperoleh nilai tegangan terbesar antar pin tap changer 3,943 kV; Hasil pengujian tegangan terapan didapat nilai tegangan isolasi antar pin sebesar 12 kV dan tegangan isolasi antar fasa 37 kV, namun untuk kondisi isolasi yang tidak baik mengakibatkan retak pada kondisi tegangan 37 kV; Hasil pengukuran tahanan isolasi, apabila terjadi over heat pada trafo mengakibatkan nilai isolasi turun; Hasil pengujian korosi belerang, tidak ditemukan adanya korosi belerang pada minyak isolasi; Hasil pengujian tegangan tembus, minyak isolasi masih dalam kondisi cukup baik dengan nilai break down voltage diatas 40 kV. Berdasarkan pengujian yang dilakukan, diperoleh kesimpulan bahwa penyebab terjadinya kerusakan ialah bahwa adanya over heat pada isolasi tap changer yang disebabkan kondisi isolasi tap changer yang tidak baik hingga akhirnya mengakibatkan tegangan busur/arching.

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In this thesis describes an experiment conducted a few steps in the process of investigation of three-phase distribution transformers 630 kVA owned by PT PLN (Persero) Distribusi Jakarta Raya dan Tangerang. Based on a visual inspection of the object, identified that the damage occurred in the tap changer. The experiment was conducted on the several aspects of the alleged cause of the damage. The experiments / tests performed include: Dissolved Gas Analysis, inspection of transformer design, applied voltage, the measurement of insulation resistance / megger, sulfur corrosion inspection, breakdown voltage. Based on testing performed, obtained the following results: Test results for Dissolved Gas Analysis damaged transformer in condition 4; examination results obtained by the voltage transformer design of the largest inter-pin tap changer 3,943 kV; Test results obtained values of applied voltage, voltage insulation between the pins at 12 kV and inter-phase voltage insulation 37 kV, but for the conditions of insulation is not good, insulation cracks on the condition of 37 kV voltage; insulation resistance measurement results, in case of over-heat in the transformer will made insulation values down; sulfur corrosion test results, no found presence of sulfur corrosion on oil insulation; test results breakdown voltage, oil insulation is still in good condition with a value break down voltage above 40 kV. Based on tests performed, we concluded that the cause of the damage is that the over-heat the tap changer insulation due to tap changer insulation condition is not good to finally lead to voltage arc / arching."

"This compendium focuses on what the research community labels as solid state gas sensors, where a gas directly changes the electrical properties of a solid, serving as the primary signal for the transducer. It starts with a visionary approach to how life in future buildings can benefit from the power of gas sensors. The requirements for various applications. Further contributions highlight current trends in new sensing principles, such as the use of nanomaterials and how to use new sensing principles for innovative applications in e.g. meteorology. "