cover
Contact Name
Dr. Basari
Contact Email
basari.st@ui.ac.id
Phone
+6221-29120943
Journal Mail Official
editor_mst@ui.ac.id
Editorial Address
Universitas Indonesia ILRC Building, 1st Floor, Depok 16424, Indonesia Kota depok, Jawa barat INDONESIA
Location
Kota depok,
Jawa barat
INDONESIA
Makara Journal of Technology
Published by Universitas Indonesia
ISSN : 23552786     EISSN : 23564539     DOI : https://doi.org/10.7454/mjt
MAKARA Journal of Technology is a peer-reviewed multidisciplinary journal committed to the advancement of scholarly knowledge and research findings of the several branches of Engineering and Technology. The Journal publishes new results, original articles, reviews, and research notes whose content and approach are of interest to a wide range of scholars. It also offers rapid dissemination. MAKARA Journal of Technology covers the recent research in several branches of engineering and technology include Electrical & Electronics Engineering, Computer Engineering, Mechanical Engineering, Chemical & Bioprocess Engineering, Material & Metallurgical Engineering, Industrial Engineering, Civil & Architecture Engineering, and Marine Engineering. Criteria used in determining acceptability of contributions include newsworthiness to a substantial part of the engineering & technology and the effect of rapid publication on the research of others. This journal, published three times each year, is where readers look for the advancement of discoveries in engineering and technology.
Articles 8 Documents
Search results for , issue "Vol. 21, No. 1" : 8 Documents clear
Encapsulation Process of Propolis Extract by Casein Micelle Improves Sunscreen Activity Sahlan, Muhamad; Dienayati, Dara; Hamdi, Darul; Zahra, Soraya; Hermansyah, Heri; Chulasiri, Malyn
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Propolis, a wax bee glue, have antioxidant activity and effective as broad spectrum UVB and UVA photoprotection sunscreens agent. To improve photoprotection activity in sunscreen cream, the propolis was encapsulated by casein micelle. The Indonesian propolis was extracted by ethanol and separated the wax by freeze precipitation. The extract was encapsulated by casein and reduced their size by ball mill homogenizer with the encapsulation efficiency about 80% and size of particles about 80 nm. The particles was applied in sunscreen cream, evaluate their stabillity and photoprotection activity Sun Protection Factor (SPF) spectrophotometer (Optometric 290s). The results shows that the selected creams were stable and have moderate photoprotection activities higher than the controls. The encapsulation process of propolis by casein micelle can improve their photoprotection activity.
A Plastic Design Method for RC Moment Frame Buildings against Progressive Collapse Faghihmaleki, Hadi
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

In this study, progressive collapse potential of generic 3-, 8- and 12-storey RC moment frame buildings designed based on IBC-2006 code was investigated by performing non-linear static and dynamic analyses. It was observed that the model structures had high potential for progressive collapse when the second floor column was suddenly removed. Then, the size of beams required to satisfy the failure criteria for progressive collapse was obtained by using the virtual work method; i.e., using the equilibrium of the external work done by gravity load due to loss of a column and the internal work done by plastic rotation of beams. According to the nonlinear dynamic analysis results, the model structures designed only for normal load turned out to have strong potential for progressive collapse whereas the structures designed by plastic design concept for progressive collapse satisfied the failure criterion recommended by the GSA code.
Purification Simulation With Vapor Permeation and Distillation-Adsorption In Bioethanol Plant Gozan, Misri; Setiawan, Mia Sari; Lischer, Kenny
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

High purity of Bioethanol is required in biofuel mixing with gasoline (EXX). In bioethanol production line, the azeotropic property of ethanol-water becomes the barrier for purification process. This study examined two bioethanol separation processes by support of simulation tools, Superpro Designer 9.0 software. Ethanol purity and a low costeconomical process were the major considerations. Purification method of vapor permeation membrane technology was compared with distillation-adsorption method. Data from previous lab experiments and some literatures were used. The results showed that distillation-adsorption method is more economical compared to vapor permeation technology. Payback period of the simulation is 3.9 years and 4.3 years to distillation adsorption and vapor permeation respectively with each IRR value is 20.23% and 17.89%. Initial investment value of vapor permeation is 9.6% higher than distillation method. Significant difference observed in operating costs, since more units involved in vapor permeation require more labors to operate.
Sorption and Ion Exchange Behaviour of Natural Zeolite Packing Purnomo, Chandra Wahyu; Lenora, Bernice; Budhijanto, Wiratni; Hinode, Hirofumi
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

It is well known that zeolite is an efficient metal ions adsorbent. The excess charge of the zeolite building blocks i.e. (AlO4)-5 and (SiO4)-4 creating a negative surface charge that attract metal cations. Beside the surface charge, zeolite also has three dimensional pore structure and reasonably large surface area which also can be used as adsorption sites. Ease of cation uptake make it suitable for many process with adsorption and desorption application. This study was conducted to observe the sorption and ion exchange behaviour of zeolite-betonite rings toward iron and cobalt cations. The results shows that the adsorption patterns follow Langmuir isotherm with the highest uptake capacity is 59,9 mg/g for Fe(II) and 57. 8 mg/g for Co(II).
Nano-Channels Early Formation Investigation on Stainless Steel 316Ti after Immersion in Molten Pb-Bi Rivai, Abu Khalid; Mardiyanto, Mardiyanto; Heinzel, Annette
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Development of fuel cladding and structural materials in Pb-Bi environment, especially at high temperature, is a critical issue for the deployment of LFR (Lead alloy-cooled Fast Reactor) and ADS (Accelerator Driven Transmutation System). This is because of the corrosive characteristic of Pb-Bi to metals as constituent materials of fuel cladding and structural of the reactors. Corrosion test of a high-chromium austenitic stainless steel i.e. SS316Ti in molten Pb-Bi at 550 ºC has been carried out for about 300 hours continuously. The characterization using SEM-EDS (Scanning Electron Microscopy - Energy Dispersive X-ray Spectroscopy) showed that an iron oxide as the outer layer and a chromium oxide as the inner layer on the surface of the specimen were formed which in general have protected the steel specimen from corrosion and dissolution attack of Pb-Bi. However, small amount of Pb could penetrate into the iron oxide layer through ultra-narrow channels. Atomic Force Microscopy (AFM) with Electrostatic Force Microscopy (EFM) mode was employed to investigate the phenomena of the nano-channels early formation. The results of the nano-scale investigation showed clearly the formation of the channels at the early time of corrosion as the way of Pb to penetrate into iron oxide outer layer.
In Vitro Toxicity Evaluation of Caffeine Imprinted Polymer (CAF-MIP) for Decaffeination Method on Normal Chang Liver Cells Hashim, Fatimah; Mehamod, Faizatul Shimal; Nawi, Naizatul Akmal
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Over consuming of caffeine is one of the factors to a few health problems such as insomnia, hypertension and cardiovascular disease. This preliminary study was conducted to evaluate the Caffeine-Imprinted Polymer (CAF-MIP) toxicity that was synthesized for a new alternative method for decaffeination. It is crucial to evaluate the toxicity of CAF-MIPas this product is potential to be used as complimentary with any drinks containing caffeine. In this study, the CAF-MIP toxicity potential was confirmed on Normal Chang Liver cell (NCLC) based on its IC50 value andacridine orange and propidium iodide (AO/PI) staining for mode of cell death observation.Proliferation assay was also conducted after 24, 48 and 72 hours at 30 μg/ml on NCLC and it showed that CAF-MIP promote NCLC growth as shown by at various concentrationof CAF-MIPincrease the percentage of NCLC viability. Observation under light microscopes on NCLC incubated wit CAF-MIP and NIP showed the normal, viable cell morphology, cuboidal and monolayer cell morphology and this can be seen with green fluorescence when view under fluorescence microscope. In conclusion, from this study, it is proved that the CAF-MIP does not initiate toxicity effects on human liver cells, meanwhile induction of cell proliferation was observed.
Influence of Polyethylene Glycol (PEG) in CMC-NH4BR Based Polymer Electrolytes: Conductivity and Electrical Study Zainuddin, Nur Khalidah; Samsudin, Ahmad Salihin
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The present work was carried with new type and promising polymer electrolytes system by development of carboxyl methylcellulose (CMC) doped NH4Br and plasticized with polyethylene glycol (PEG). The sample was successfully prepared via solution casting with no separation phase and good mechanical properties. The electrical conductivity and thermal conductivity of CMC-NH4Br-PEG based PEs system have been measured by the electrical impedance spectroscopy method in the temperature range of 303–373 K. The highest ionic conductivity gained is 2.48 x 10-3 Scm-1 at ambient temperature for sample contain with 8 wt. % PEG. It can be concluded that the plasticized is accountable for the conductance and assist to enhancing the ionic conductivity of the CMC-NH4Br-PEG electrolyte system. The addition of PEG to the CMC-based electrolyte can enhance towards the cation mobility which is turn increases ionic conductivity. The conductivity-temperature of plasticized BdPEs system was found obeys the Arrhenius relation where the ionic conductivity increases with temperature and activation energy for the ions hopping of the highest conducting PEs system only required small value to migrate. The electrical studies show a non-Debye behaviour of BdPEs based on the analyzed data using complex permittivity, ε* and complex electrical modulus, M* of the sample at different temperature.
Synthesis of LiBOB Fine Powder to Increase Solubility Wigayati, Etty Marti; Lestariningsih, Titik; Ratri, Christin Rina; Purawiardi, Ibrahim; Prihandoko, Bambang
Makara Journal of Technology Vol. 21, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Lithium bis (oxalate) borate or LiBOB compound has captured interest of researchers, because it is potentially viable to be used as electrolyte salt in lithium-ion battery system. This compound is easy to synthesize and considered to be more environmentally friendly compared to conventional electrolyte salt because LiBOB does not contain halogen element. This research focused on the synthesis of LiBOB fine powder, which main purpose is improving LiBOB salt solubility in liquid electrolyte solution. This will aid the ion transfer between electrodes which in turn will increase the electrolyte performance. Solid state reaction was employed in this experiment. Synthesis of LiBOB compound was performed by reacting oxalic acid dihydrate, lithium hydroxide monohydrate, and boric acid. The resulting powder was then processed into fine powder using ball milling technique with varying milling time (0, 6, 10, and 13) hour. Microstructure of the sample was then analyzed to obtain information regarding phase formation, functional groups, grain surface morphology, surface area, pore volume, solubility, and ionic conductivity. The analysis shown that LiBOB and LiBOB hydrate phase was formed during the reaction, there was no changed in existing phase during milling process, crystallinity index was shifted to lower value but there was no difference in functional groups. Highest value in surface area was found to be 83.11 m2/g, with pore volume of 1.21311e+02 A at 10 hours milling. Smaller powder size resulted in higher solubility, unfortunately the ionic conductivity was found to be decreased.

Page 1 of 1 | Total Record : 8