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"ABSTRAKPenggetasan material yang dilapisi Cadmium secara. elektrolitik (elektroplating) merupakan kasus yang sering ditemui di industri, khususnya industri pesawat terbang, padahal lapisan tersebut diperlukan untuk meningkatkan ketahanan korosi dan ketahanan aus. Penggetasan ini mengarah kepada terjadinya kegagalan dan kerusakan yang tertunda (delayed brittle failure). Material/komponen yang digunakan dalam penelitian ini adalah baja kekuatan tinggi AISI 4340 yang digunakan untuk komponen landing gear pesawat terbang. Material tersebut mengalami proses pelapisan dengan Cadmium yang selanjutnya mengalami proses pemanasan (baking) pada temperatur 190° C dan 2500 C masing - masing selama 15 jam, 24 jam, 48 jam, 72 jam dan 100 jam. Dalam menganalisa kerusakan digunakan mikroskop optik dan Scanning Electron Microscope (SEM), sedangkan pengujian - pengujian mekanis yang dilakukan adalah pengujian ketahanan (endurance test), pergujian tarik dan pengujian kekerasan. Dari hasil pengamatan foto dengan mikroskop optik dan SEM dapat diketahui bahwa penggetasan material disebabkan oleh atom - atom hidrogen yang berdifusi ke dalam benda kerja selama proses elektroplating yang dikenal dengan nama "hydrogen embrittlement". Waktu dan temperatur baking yang diperlukan agar material memenuhi spesifikasi (tidak terjadi penggetasan oleh hidrogen) adalah temperatur 250° C sampai minimal 48 jam. Kekerasan setelah proses baking akan menurun dengan meningkatnya temperatur dan waktu baking. "

"Expert techniques for extracting hydrogen from water using transition metal oxides as catalysts Solar Hydrogen Generation details the complex process of separating hydrogen from oxygen--photoelectrolysis. This book comprehensively covers the chemical characteristics of transition metal oxides, explaining how to covert solar energy to electron energy through transition metal oxides. Past experimentations and future directions are discussed. Solar Hydrogen Generation Comprehensively reviews physical characteristics of transition metal oxides both in electrochemical and photocatalytic applications Includes history and future prospects for water photoelectrolysis Reviews state-of-the-art achievements in the fields of condensed matter physics, nanostructured material science, electrochemistry, and photocatalysis Addresses potential problems and solutions In-depth coverage: Hydrogen Production; Electrochemistry and Photoelectrolysis; Transition Metal Oxides; Molecular Structure, Crystal Structure, and Electronic Structure; Optical Properties and Light Absorption; Bandgap, Band Edge, and Engineering; Impurity, Dopants, and Defects; Photocatalytic Reactions, Oxidation and Reduction; Organic and Inorganic Systems; Surface and Interface Chemistry; Nanostructured and Morphology; Synchrotron Radiation and Soft X-Ray Spectroscopy"--Provided by publisher."This pioneering guide covers one of the most promising sustainable energy carriers--water hydrogen--and shows how to extract hydrogen from water using transition metal oxides as catalyst."

"Perkembangan dalam pencarian energi alternatif telah banyak dilakukan seiring dengan kesadaran akan pentingnya penggunaan sebuah bahan bakar yang ramah lingkungan dan hemat serta efisien. Salah satu energi alternatif yang telah lama dikembangkan adalah hidrogen. Gas hidrogen (H2) dapat dihasilkan dari air (H2O) dengan cara elektrolisis yang dibantu oleh katalisator (KOH) dengan memanfaatkan reaksi oksidasi yang terjadi. Dengan menginjeksikan gas hasil elektrolisis air itu ke dalam ruang bakar melalui saringan udara yang berada tepat sebelum karburator, diperoleh beberapa pengaruh yang terjadi pada hasil pembakaran. Di dalam ruang bakar, gas hidrogen berfungsi sebagai bahan bakar tambahan disamping bahan bakar utama yaitu bensin. Hasil dari pembakaran dengan penambahan injeksi gas hasil hasil elektrolisis ini berpengaruh pada fuel consumption, power dan emisi gas buang.

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Progresses in the search for alternative energy have been carried out along with the awareness of the importance of using a fuel efficient and environmentally friendly aspect. One of the alternative energy that has been developed is hydrogen. Hydrogen gas (H2) can be produced from water (H2O) by electrolysis is assisted by a catalyst with utilizing the oxidation reaction during the process. By injecting gas from the electrolysis of water into the combustion chamber through the air filter which is before the carburetor obtained some influence that occurs in combustion products. Inside the combustion chamber, hydrogen gas serves as fuel in addition to the main fuel is gasoline. Results of combustion with the addition of gas injection are effect on fuel consumption, power and exhaust emissions."

"The presence of sulphur compounds in natural gas can interfere to the quality of natural gas. The decline of combustion gas capacity, metal instrument corrosion in gas piping, and the environmental pollution from gas emission can affect by their presence. Bio-filter is one of the methods that selected to reduce sulphur content in natural gas. A lab scale study of hydrogen sulphide reduction in natural gas had conducted in oil and gas field using bio-filter method. The bio-filter system (±1 L volume) contains an active carbon and thiosulphide medium as a substrate, Thiobacillus thioparus as a single culture of sulphur bacteria, and Thiobacillus thioparus with sludge as a mixed culture of sulphur bacteria. The study of hydrogen sulphide reduction was conducted with continuous flow line process. The gas flow rate approximately 1.5 L/min with a fluctuate presence of Hydrogen sulphide (approximately 40 - 70 mg/L). The bio-filter system contains active carbon, thiosulphide medium, and single culture of T. thioparus appear as a good filter for hydrogen sulphide reduction. During 24 hours, the hydrogen sulphide reduction obtains 93% to 16%. When culture media added, the hydrogen sulphide reduction will increase almost 60% and then the reduction decrease to 4% after 20 hours. It is concluded that the bio-filter have potential to develop for sulphur reduction in natural gas."

"Pemutihan gigi dilakukan untuk gigi yang mengalami diskolorasi menggunakan hidrogen peroksida. Salah satu teknik dalam pemutihan gigi adalah at-home bleaching. Aplikasi bahan pemutih gigi juga dapat dilakukan pada gigi yang telah ditumpat dengan resin komposit. Tujuan dari penelitian ini adalah mengetahui pengaruh lama aplikasi bahan pemutih gigi hidrogen peroksida 6% terhadap kekerasan resin komposit hibrid. Penelitian ini menggunakan 30 spesimen yang dibagi menjadi 3 kelompok, yaitu 10 spesimen kontrol, 10 spesimen yang diaplikasi bahan pemutih gigi selama 4 jam dan 10 spesimen yang diaplikasi bahan pemutih gigi selama 8 jam. Aplikasi bahan pemutih gigi dilakukan selama 4 hari. Pengukuran kekerasan dilakukan per hari menggunakan Knoop Microhardness Tester.Hasil dari penelitian ini menunjukkan perbedaan penurunan kekerasan berdasarkan lama aplikasi bahan pemutih gigi. Namun tidak terdapat perbedaan penurunan kekerasan bermakna dibandingkan dengan kelompok kontrol. Dengan demikian dapat disimpulkan bahwa bahan pemutih gigi hidrogen peroksida 6% dapat digunakan pada pasien dengan tumpatan resin komposit hibrid dengan aplikasi 4 jam selama 1 hari.

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Dental bleaching is one of treatment for discoloured teeth using hydrogen peroxide. One of dental bleaching method is at-home bleaching. Application of bleaching agent is also applied on the tooth that has been restorated with dental composite resin. The purpose of this research is to analyse the effect of different time of 6% hydrogen peroxide application to the surface hardness of hybrid composite resin. In this research 30 specimens hybrid composite resin were divided into 3 groups of specimen. These are 10 specimens as control group, 10 specimens applied with bleaching agent for 4 hours and 10 specimens applied with bleaching agent for 8 hours each day for 4 days. Measurement with Knoop Hardness Tester has been done each day.The result of this research is the surface hardness value of hybrid composite resin was decreased significantly after the application of bleaching agent 6% hydrogen peroxide according to time of application. But there?s no significantly differences compared to control group. The conclusion is bleaching agent that contain 6% hydrogen peroxide can be used for patient with hybrid composite resin in 4 hour application for one day."

"Examination of the hydrogen gas detection system. Examination of the hydrogen gas detection system in IEBE have been done. The hydrogen gas detection system in IEBE attached sensor to detect the existence of secretary hydrogen gas from system because leakage or imperfect its hydrogen combustion. Intention of examination is to know the temperature of around sensor and respon of indicator warning, evacuate and faiture...."