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Abstrak :
ABSTRACT
Separation and storage of hydrocarbon gases are very important in the petrochemical industries. Metal organic Frameworks (MOFs) are novel hybrid materials consisting of organic and inorganic components in crystalline lattices. With their outstanding characteristics, such as high surface area, tuneable pore size, and controllable pore properties, MOFs are able to possess high selectivity towards certain gas species. In this study, a series of MOF 74s with high densities of open metal sites were synthesized with 2 5 Dihydroxyterephthalic acid H4DOBDC as the ligand and metal sources Zn, Co, Ni, and Mg.The synthesized MOF 74s were characterized by X ray diffraction, scanning electron microscope, and thermogravimetric analysis. The MOF 74 samples also undergo N2 adsorption to measure their BET surface areas, CO2 adsorption to measure their pore size distribution, as well as hydrocarbon adsorption with gases methane CH4 , acetylene C2H2 , ethane C2H6 , propylene C3H6 , propane C3H8 , and carbon dioxide CO2 .The results show that all the MOF 74 samples have high adsorption capacities of C2 C3 hydrocarbons as well as high ideal selectivities of of C2 C3 hydrocarbons over CH4. Out of all the samples Mg MOF 74 have the highest values of hydrocarbon adsorption capacities for C2 C3 hydrocarbons and highest ideal selectivities of hydrocarbons over CH4. This suggests that MOF 74s can be potential candidates for hydrocarbon separation and storage.

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ABSTRAK
Pemisahan dan penyimpanan gas hidrokarbon merupakan proses yang sangat penting dalam industry petrokimia. Metal-Organic Frameworks MOF adalah material berpori baru yang terdiri dari komponen organic dan inorganic di dalam struktur kristalnya. Dengan karakteristik yang berguna seperti luas permukaan yang tinggi, ukuran pori yang bias diubah, dan properti pori yang bias diganti, MOF memiliki selektivitas tinggi terhadap jenis gas tertentu. Di riset ini, MOF-74 yang memiliki kepadatan situs logam terbuka tinggi dibuat dari 2-5-Dihydroxyterephthalic acid H4DOBDC sebagai ligan dan Zn, Co, Ni, dan Mg sebagai sumber logam. Sampel MOF-74 dikarakterisasi dengan difraksi X-ray, scanning electron microscope, dan thermogravimetric analysis. Luas permukaan dari sampel MOF-74 diukur menggunakan adsorpsi gas nitrogen. Distribusi ukuran pori dari sampel MOF-74 juga diukur dengan menggunakan adsorpsi karbon dioksida.Kemampuan adsorpsi dari sampel MOF-74 juga diuji dengan menggunakan gas metana CH4 , asetilen C2H2 , etana C2H6 , propilena C3H6 , propana C3H8 , and karbon dioksida CO2 . Hasil dari penelitian menunjukkan bahwa semua sampel MOF-74 memiliki kapasitas adsorpsi dari gas hidrokarbon C2 ndash; C3 tinggi dan juga memiliki selektivitas ideal yang tinggi terhadap gas hidrokarbon C2 ndash; C3 dibandingkan dengan metana. Mg-MOF-74 memiliki kapasitas adsorpsi gas hidrokarbon C2 ndash; C3 yang paling tinggi dibandingkan sampel lainnya. Hasil ini menunjukkan bahwa Mg-MOF-74 memiliki potensi yang tinggi untuk aplikasi separasi dan penyimpanan gas hidrokarbon.Kata Kunci: MOF, Adsorpsi Gas Hidrokarbon, Penyimpanan Gas Hidrokarbon, Material Berpori, MOF-74.

Abstrak :
Teknologi penghantar panas terus mengalami perkembangan karena kebutuhan yang terus meningkat. Salah satunya adalah teknologi pipa kalor yang terus dikembangkan dari segi kemampuan sumbu kapilernya dalam memompa fluida kerja. Sebuah pengembangan berupa Lotus-Type Porous Material yang diterapkan pada sumbu kapiler di pipa kalor diprediksikan akan meningkatkan kemampuan dari pipa kalor tersebut. Metode fabrikasi yang dilakukan pada penelitian ini adalah Centrifugal casting dengan bahan dasar berupa serbuk tembaga. Komposisi serbuk tembaga dan juga kecepatan rotasi yang dihasilkan dari mesin Centrifugal casting turut memberikan pengaruh pada porositas yang terbentuk pada sumbu kapiler yang tentunya juga akan mempengaruhi performa dari sumbu kapiler tersebut.

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Heat transfer technology continues to development because of the increasing demands. One of which is heat pipe technology are continuously being developed in terms of wick ability to pumping the working fluid. Lotus-Type Porous Material is one of fabrication development which applied to the wick is predicted will increase it's ability. Fabrication method in this research to make heat pipe's wick is use Centrifugal casting method that use copper powder as base material. The composition of copper powder and rotational velocity of the centrifugal casting machine can influence the performance of heat pipe and also the thickness of the wick that will be formed.

Abstrak :
This book presents the work done by the RILEM Technical Committee 227-HPB (Physical properties and behaviour of High-Performance Concrete at high temperature). It contains the latest research results on the modelling of concrete behaviour at high temperature. Some monographs on the subject have been published already but generally they do not cover the whole range of possibilities which are encountered in the literature as well as in practice. Moreover, there has been a rapidly increasing development of computational models during the last twenty years, which deserves attention. Therefore, it is the aim of this report to compile and present most of the tools that are proposed in the literature and are nowadays available for practice in some commercial computational packages. The book is divided in 3 main chapters dealing with: - engineering modelling - advanced modelling - constitutive parameters including hydral, thermal and mechanical parameters.

Abstrak :
In the current study, algorithm pore distribution models of porous material are developed for insulator application through establishing the effects of pore shape, content and size, which acts as an expression of the nature of porous material. The arrangement of pore distribution in the polypropylene (PP) system is determined by various irregular shape studies. The model is simulated through representative volume elements (RVEs) with the pore content, which is set in the range of 5-24 vol.%, while the pore sizes are used around 0.2, 2 and 3 mm of diameter size. A significant improvement in the optimization of the insulator model is showed by synergistic effect on decreasing thermal conductivity in increasing the content of the pores. The results obtained show that the various irregular shapes of porous material produce various final results in thermal conductivity. The thermal conductivity of the porous material that contained 24 vol.% of pores significantly improved from 0.22 W/m.K to 0.158 W/m.K. Comparison of the simulation showed that the data matched well with the Maxwell-Eucken and Hashin–Shtrikman bounds models.