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"[ABSTRAKHidrogen merupakan salah satu unsur yang dapat dijadikan sebagai bahan bakar alternatif karena BBH atau bahan bakar hidrogen bersifat ecoenergi dengan proses pembakaran yang hanya menghasilkan air dan energi (listrik dan panas). Salah satu teknologi penghasil hidrogen adalah dengan metode Contact Glow Discharge Elektrolisis atau CGDE. Penelitian ini menggunakan metode CGDE dengan multi katoda dan penambahan etanol dengan tujuan dapat meningkatkan laju produksi hidrogen dan efektivitas proses.pada penelitian ini akan dilihat pengaruh penambahan jumlah katoda, pengaruh konsentrasi etanol dan diameter katoda terhadap laju produksi dan efektivitas hidrogen. Dari karakterisasi arus dan tegangan yang diperoleh pada penelitian ini, dapat disimpulkan bahwa arus akan semakin meningkat seiring dengan bertambahnya jumlah katoda. Penggunaan multi katoda pada proses CGDE juga terbukti meningkatkan produksi hidrogen pada tegangan dan konsumsi energi yang sama. Penambahan zat aditif etanol juga dilakukan pada penelitian ini dan memperoleh hasil bahwa semakin tinggi konsentrasi etanol maka akan semakin tinggi produksi dan efektivitas gas Hidrogen yang dihasilkan. Selain itu, penelitian ini juga membuktikan bahwa semakin besar diameter katoda maka laju produksi akan semakin tinggi, namun konsumsi energi menjadi meningkat dan tidak sebanding dengan peningkatan laju produksi sehingga menghasilkan efektivitas yang semakin kecil. Proses CGDE multi katoda pada penelitian ini menunjukkan peningkatan efektivitas proses sebesar 76 kali lipat dibandingkan dengan elektrolisis Faraday.

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ABSTRACTHydrogen is one of elements that can be used as an alternative energy. The combustion of Hydrogen only produces water and energy. Therefore, hydrogen is called as ecoenergy. One of technology that can produce hydrogen is Contact Glow Discharge Electrolysis or CGDE. CGDE is one of plasma electrolysis that uses electrolyte solution and inert electrode to produce hydrogen in high voltage. This research uses CGDE method with multi-cathode and ethanol in order to increase hydrogen production and the effectivity of process. In this research, we will explore the effect of increasing cathode number, etanol addition, and increasing of cathode diameter. From characterization of current and volatge, we can conclude that the increasing of cathode number can increase the current that through into cathode. Utilization of multi-cathode in CGDE is proven that can increase the hydrogen production at the same voltage and energy consumption. The addition of ethanol has done in this research and we can conclude that when we increase the concentration of ethanol, the hydrogen production will be increased either at the same voltage. In addition, this research also prove that the bigger diameter of a cathode will increase the production rate, but the energy consumption increases higher than the production rate. Therefore, the increasing of diameter of cathode is not effective to use in CGDE. The CGDE multi-cathode on this research indicated increasing of effectiveness as much as 76 times higher than the Faraday Electrolysis., Hydrogen is one of elements that can be used as an alternative energy. The combustion of Hydrogen only produces water and energy. Therefore, hydrogen is called as ecoenergy. One of technology that can produce hydrogen is Contact Glow Discharge Electrolysis or CGDE. CGDE is one of plasma electrolysis that uses electrolyte solution and inert electrode to produce hydrogen in high voltage. This research uses CGDE method with multi-cathode and ethanol in order to increase hydrogen production and the effectivity of process. In this research, we will explore the effect of increasing cathode number, etanol addition, and increasing of cathode diameter. From characterization of current and volatge, we can conclude that the increasing of cathode number can increase the current that through into cathode. Utilization of multi-cathode in CGDE is proven that can increase the hydrogen production at the same voltage and energy consumption. The addition of ethanol has done in this research and we can conclude that when we increase the concentration of ethanol, the hydrogen production will be increased either at the same voltage. In addition, this research also prove that the bigger diameter of a cathode will increase the production rate, but the energy consumption increases higher than the production rate. Therefore, the increasing of diameter of cathode is not effective to use in CGDE. The CGDE multi-cathode on this research indicated increasing of effectiveness as much as 76 times higher than the Faraday Electrolysis.]"

"Telah dilakukan proses sintesis LiFe 1-x VxPO4/C untuk katoda baterai litium ion. Pada bahan ini, sintesis diawali dengan pembuatan LiFePO4 yang dilakukan melalui proses hidrotermal dengan bahan dasar LiOH, NH4H2PO4 dan FeSO4.7H2O. Setelah LiFePO4 disintesis, lalu dilakukan penambahan variasi vanadium serbuk yang bersumber dari H4NO3V dan karbon yang berasal dari hasil pirolisis sukrosa selama 2 jam pada 400 C. Bahan-bahan dicampur menggunakan ball-mill lalu dikarakterisasi menggunakan analisis termal STA untuk menentukan temperatur sintering. Hasilnya memperlihatkan bahwa transisi terjadi pada temperatur sekitar 700 C yang kemudian dijadikan patokan untuk menentukan proses sintering. Sintering dilakukan selama 4 jam lalu hasilnya dikarakterisasi menggunakan difraksi sinar-X XRD. Struktur mikto dan morfologi permukaan selanjutnya dianalisis menggunakan mikroskop elektron SEM. Hasil karakterisasi dengan XRD menunjukkan bahwa fasa LiFe 1-x VxPO4/C telah terbentuk dengan struktur berbasis olivin. Hasil SEM menunjukan adanya persebaran partikel LiFe 1-x VxPO4/C walaupun beberapa terlihat masih beraglomerasi. Proses pembuatan baterai dilakukan dari bahan hasil sintesis dan diuji menggunakan electrochemical impedance spectroscopy EIS dan uji performa melalui cyclic voltametry CV dan charge and discharge CD . Hasil EIS menunjukan bahwa doping dengan vanadium meningkatkan konduktifitas yang cukup berarti. Hal yang sama juga terjadi dengan adanya karbon sintesis dari sukrosa walaupun masih lebih rendah jika dibandingkan dengan karbon komersial. Uji performa menunjukan bahwa penambahan vanadium meningkatkan kapasitas 51.06 mAh/g saat charging dan 49.42 mAh/g saat discharging dengan beda potensial 3.581 V saat charging dan 3.319 V saat discharging. Hasil yang didapatkan ini cukup menjanjikan untuk penggunaan selanjutnya sebagai katoda baterai litium ion.

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Synthesis of LiFe 1 x VxPO4 C used for lithium ion battery cathode has been carried out. In the process, the synthesis was begun by synthesizing of LiFePO4 through a hydrothermal method with the precursors of LiOH, NH4H2PO4 and FeSO4.7H2O. The as synthesized LiFePO4 was then mixed with H4NO3V and carbon pyrolyzed from sucrose for 2 hours at 400 C. The mixture was mixed in a ball mill and then was characterized using a thermal analyzer to determine the transition temperature at which sintering at 700 C for 4 hours was obtained. X ray diffraction XRD was performed to analyzed the crystal structure whereas scanning electron microscope SEM was used to examine the microstructure and surface morphology.

XRD results show that the phase LiFe 1 x VxPO4 C has been formed with an olivine based structure. SEM results showed the distribution of LiFe 1 x VxPO4 C particles are mostly distributed. The batteries were prepared from the as synthesized materials and was tested using electrochemical impedance spectroscopy EIS, cyclic voltammetry CV and charge and discharge CD performance test. The EIS results showed that doping with vanadium improved the conductivity. The same was true with the carbon even at a smaller value compared to that of the commercial one. The performance test showed that the addition of vanadium increased the capacity of about 51.06 mAh g with a potential of 3.581 V at charging and 49.42 mAh g with a potential of 3.319 V at discharging. These results are promising in terms of using this material for lithium ion battery cathode development."

"In 1989-90 the map of Europe was transformed peacefully-without a war, unlike other great ruptures of the international order such as 1815, 1870, 1918, and 1945. What role did international summitry play in the dénouement of the cold war? So far scholars have focused on long-term systemic factors, Gorbachevs reform agenda, or the impact in 1989 of people power. This major multinational study, based on archives from both sides of the Iron Curtain, adopts a novel perspective by exploring the contribution of international statecraft to the dissolution of Europes bipolar order. This is done through the examination of key summit meetings from 1970 to 1990 across three phases Thawing the cold war, living with the cold war, and transcending the cold war and in three main strands: the superpowers and arms control, their triangular relationship with China, and the German question. The threads are drawn together in a sweeping analytical conclusion. The book includes fascinating insights into key statesman such as Richard Nixon and Ronald Reagan, Leonid Brezhnev and Mikhail Gorbachev, Willy Brandt and Helmut Kohl, Zhou Enlai and Deng Xiaoping, both as thinkers about the international system and also practitioners of summit bargaining. Particular attention is devoted to the cultural dimensions of summitry, as performative acts for the media and as engagement with the other across ideological divides. Written in lively prose, this book is essential reading for those interested in modern history, contemporary politics, and international relations addressing issues that still shape the world today."

"Penelitian ini mengkaji kelayakan pemanfaatan energi dingin LNG pada terminal penerima dan regasifikasi LNG di Pulau Bangka yang dapat dimanfaatkan untuk sektor perikanan sebagai cold storage. Energi dingin dengan suhu sekitar -161˚C (-260˚F) yang terkandung dalam LNG tersebut sebelum digasifikasikan ke unit vaporizer terlebih terlebih dahulu diintegrasikan kepada unit heat exchanger yang dilakukan untuk memanfaatkan energi dingin LNG untuk mencairkan karbon dioksida yang menjadi refrigerant pada sistem pendingin ikan tersebut. Untuk mengetahui kelayakan proyek ini, dilakukan kajian tekno-ekonomi proyek dengan jangka waktu operasi selama 20 tahun yang meliputi kajian desain peralatan fasilitas regasifikasi untuk mensupport kebutuhan pembangkit listrik 100 MW load follower dan juga fasilitas cold storage, kajian biaya Capex dan Opex, kajian keekonomian, kajian sensitivitas dengan menggunakan software crystal ball serta kajian penghematan yang diperoleh dengan pemanfaatan gas hasil regasifikasi LNG ini dengan perbandingan terhadap jenis bahan bakar lain yakni HSD. Hasil kajian keekonomian mennjukkan bahwa proyek ini layak untuk dijalankan dengan kapasitas regasifikasi LNG sebesar 11.07 MMSCFD, diperlukan biaya investasi sebesar USD 48 Juta dengan biaya operasi dan pemeliharaaan tahunan sebesar USD 9.1 Juta. Parameter yang menunjukkan kelayakan proyek ini adalah IRR sebesar 14%, NPV sebesar USD 79 Juta dan Payback Period selama 7.7 tahun.

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This study examines the feasibility of LNG cold energy utilization at the receiving terminal and regasification of LNG in Bangka Island which can be utilized for the fisheries sector as a cold storage. Cold energy with temperatures around -161˚C (- 260˚F) contained in the LNG before to be gasified to vaporizer unit, firstly LNG can utilized to the heat exchanger to utilize LNG cold energy to liquefy the carbon dioxide that can used as a refrigerant in the cooling system the cold storage system.

To determine the feasibility of this project, carried out the study of techno-economic of the project with the duration of the operation for 20 years which includes the study design equipment regasification facility to support the needs of the power plant of 100 MW load follower and cold storage facilities, study costs Capex and Opex, the study of economics, sensitivity studies using software crystal ball and assessments savings gained with the use of gas LNG regasification results with comparisons against other fuel types like High Speed Diesel (HSD).

The results of the economic study shows that the project is feasible to run with LNG regasification capacity of 11:07 MMSCFD, required an investment cost of USD 48 million with an annual operating cost and maintainability of USD 9.1 million. Parameters that indicate the feasibility of this project is an IRR of 14%, NPV of USD 79 Million and Payback Period for 7.7 years."

"Data dari International Association of Refrigerated Warehouse (IARW) mengeluarkan laporan kapasitas cold storage, dimana India menduduki puncak kapasitas terbesar dengan kapasitas 131 juta meter kubik, yang kemudian disusul oleh Amerika dengan kapasitas 115 juta meter kubik Indonesia dibanding dengan Negara lain seperti India, Amerika,masih tertinggal jauh dengan kapasitas cold storage sebanyak 200 ribu meter kubik. Maka dari hal tersebut Indonesia masih perlu memperluas dan memperbanyak perusahaan penyedia jasa cold storage untuk membantu menangani permintaan kebutuhan cold storage yang terus meningkat. Contoh nya ada beberapa perusahaan di Indonesia seperti PT Adib Cold Logistics yang menyediakan beragam layanan kontrol suhu seperti cold storage dan chiller. Dilengkapi dengan sistem pendingin Mayekawa Newton terbaru yang aman untuk lingkungan dan menghasilkan suhu yang stabil dalam rentang -25˚C hingga +25˚C. Akan tetapi setiap perusahaan yang menyediakan jasa pendinginan, terutama yang menggunakan cold storage pasti akan mengeluarkan biaya untuk melakukan kegiatan maintenance. Terdapat beberapa faktor yang akan mempengaruhi biaya maintenance perusahaan, yang paling utama adalah sistem refrigerasi yang digunakan. Karena dari sistem refrigerasi yang digunakan perlu dilakukan pengecekan dan perbaikan berkala, terhadap komponen sistem refrigerasi seperti kompresor, kondensor dan evaporator. Untuk menghitung nya ,diusulkan perhitungan mengenai perhitungan beban pendingin, kapasitas pendingin dengan diagram psikometri dan perhitungan COP untuk dibandingkan dengan spesifikasi dari sistem pendingin Mayekawa Newton.Studi ini membahas mengenai apakah PT.Adib Cold Logistic sudah berjalan sesuai dengan spesifikasi alat Mayekawa Newton dalam mendinginkan cold storage nya. Dalam studi ini dilakukan perhitungan  beban pendingin pada beban produk, beban lampu, beban orang, beban elektrikal, beban material, dan beban infiltasi. Dilakukan juga perhitungan kapasitas pendingin melalui diagram psikometri dari diagram p-h. Metodologi yang digunakan yaitu metode kuantitafi  dan eksperimen . Metode kuantitatif akan dilakukan pengambilan data secara langsung di PT.Adib Cold Logistic . Metode Analitik  akan melakukan perhitungan yang berfokus kepada beban pendingin serta kapasitas pendingin sesuai dengan rumus yang berlaku . Berdasarkan hasil studi didapatkan bahwa beban pendingin dapat berkurang sebanyak 4,27 kW dengan menerapkan improvement yang diberikan oleh penulis, dan dapat menghemat biaya Rp.53.299.028 dalam rentang 1 tahun.

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ata from the International Association of Refrigerated Warehouse (IARW) has released a report on cold storage capacity, where India ranks first with the largest capacity of 131 million cubic meters, followed by the United States with a capacity of 115 million cubic meters. Compared to other countries like India and the United States, Indonesia is still far behind with a cold storage capacity of only 200,000 cubic meters. Therefore, Indonesia still needs to expand and increase the number of cold storage service providers to help meet the increasing demand for cold storage. An example of such companies in Indonesia is PT Adib Cold Logistics, which provides various temperature control services such as cold storage and chiller. Equipped with the latest Mayekawa Newton cooling system that is environmentally friendly and produces stable temperatures ranging from -25˚C to +25˚C. However, every company that provides cooling services, especially those using cold storage, will incur costs for maintenance activities. There are several factors that will affect the maintenance costs of a company, with the most important one being the refrigeration system used. Because periodic checks and repairs need to be carried out on components of the refrigeration system such as compressors, condensers, and evaporators. To calculate these costs, it is proposed to calculate the cooling load, cooling capacity using psychrometric charts, and COP calculations to compare them with the specifications of the Mayekawa Newton cooling system. This study discusses whether PT Adib Cold Logistics operates according to the specifications of the Mayekawa Newton equipment in cooling its cold storage. In this study, calculations are made for the cooling load on product load, lighting load, personnel load, electrical load, material load, and infiltration load. Cooling capacity is also calculated using psychrometric charts from the p-h diagram. The methodology used is quantitative and experimental. The quantitative method involves collecting data directly from PT Adib Cold Logistics. The analytical method focuses on calculating the cooling load and cooling capacity according to applicable formulas. Based on the study results, it was found that the cooling load can be reduced by 4,27 kW by implementing the improvements provided by the author, resulting in a cost savings of Rp.53.299.028 within a one-year period."

"Start prcess,particularly cold start condition is considered important to be focused in terms of emission reduction due to high unberned hydrocarbon (HC) concertration in the exhaust gas....."