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Widyariset
Published by Pusbindiklat Peneliti LIPI
ISSN : -     EISSN : 24610976     DOI : 10.14203
Core Subject : Science, Engineering,
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Widyariset is a scientific journal which publishes the results of research and development, assessment, and systematic thinking about Natural Science.
Arjuna Subject : Umum - Umum
Articles 476 Documents
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SYNTHESIS OF POLYURETHANE MICROCAPSULE USING INTERFACIAL POLYMERIZATION AS SELF HEALING COATING MATERIAL Athanasia Amanda Septevani; Evi Triwulandari; Dewi Sondari
Widyariset Vol 15, No 2 (2012): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.15.2.2012.265–272

Abstract

Polyurethane microcapsule had been made as self healing coating material. Polyurethane microcapsule synthesis had been conducted by interfacial polymerization both spontaneous polymerization and prepolymer polyurethane polymerization using glycerol as renewable palm oil polyol. Based on FTIR-Spectra showed the functional group of polyurethane formed both spontaneous and prepolymer polyurethane polymerization. Polyurethane microcapsule formed was in spherical form. The particle size prepared by spontaneous polimerization was smaller than particle prepared by prepolymer polymerization at range 20,51±12,7 and 139,2±72,3 μm respectively.
Electrochemical Performance of Li4-xTi5CuxO12 for Lithium Ion Capacitor Applications Ahmad Sohib; Achmad Subhan; Wahyu Bambang Widayatno; Slamet Priyono; Chairul Hudaya; Ilma Nuroniah; Sherly Novia Sari; Bambang Prihandoko
Widyariset Vol 6, No 1 (2020): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.6.1.2020.43-50

Abstract

Lithium titanat (LTO) has attracted considerable attention since it has unique characteristics for energy storage application. Doped LTO is one of approach to improve LTO performance. To date, doped LTO performance in full cell lithium ion capacitor has rarely been discussed. This study is aimed to synthesize Cu-doped LTO via solid state reaction and high energy milling and investigate its electrochemical performance in full cell of lithium ion capacitor. Cu-doped LTO is synthesized via solid state method with high energy milling. Diffraction pattern exhibit that Cu-doped LTO has been successfully synthesized even some impurities such as Baddeleyite, ZrO2, and Li2O appear in each sample. Cyclic voltammogram profile of half-cell based Cu-doped LTO shows that the oxidation and reduction peaks are declined due to its impurities contain. electrical resistance of LTO and Cu-doped LTO becomes smaller as increasing dopant contain while charge transfer resistance is higher. Full cell performance of LIC represent that undoped  LTO//Activated carbon shows higher capacitance, namely 430 µFg-1 at specific current of 50 mAg-1than that of 2.5%-Cu-doped LTO//AC holds 15 µFg-1.
PERILAKU KOROSI ATMOSFER BAJA GALVANIS SETELAH EKSPOS SINGKAT DI PELABUHAN RATU, JAWA BARAT Gadang Priyotomo, S.T., M.Si.; Siska Prifiharni; Lutviasari Nuraini; Ahmad Royani; Sundjono Sunjono; Hadi Gunawan
Widyariset Vol 5, No 1 (2019): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.5.1.2019.37-46

Abstract

Studi korosi atmosfer baja galvanis dilakukan di daerah pantai Pelabuhan Ratu, Jawa Barat, dimana diatur waktu ekspos hingga 76 hari. Perfoma ketahanan korosinya ditentukan dengan metode kehilangan berat. Morfologi permukaan, komposisi unsur dan senyawa produk korosi baja galvanis diamati dengan menggunakan scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X-Ray diffraction (XRD). Faktor lingkungan udara yang mempengaruhi proses korosi dimonitoring selama ekspos antara lain kelembaban relatif, suhu udara, suhu embun dan salinitas udara. Berdasarkan hasil, nilai laju korosi material adalah 0,64 mpy di waktu ekspos 27 hari dan 0,12 mpy di 76 hari. Prediksi umur pakai lapisan seng baja galvanis adalah 18 tahun. Kombinasi waktu basah dan kering bergantian ditandai dengan fluktuasi kelembaban udara dan suhu menciptakan lapisan protektif kusam dan kelabu seiring peningkatan waktu ekspos. Keberadaan klorida sebagai pemercepat reaksi korosi kurang berperan, dikarenakan kadar salinitas yang kecil. Fasa produk lapisan seng adalah zincite (ZnO) dan hydrozincite (Zn5(CO3)2.(OH)6) dimana lapisan tersebut sangat protektif untuk serangan korosi berlanjut.
PENGARUH JUMLAH SALURAN MASUK UDARA TERHADAP DISTRIBUSI KECEPATAN UDARA PENGERING PADA ALAT PENGERING TIPE SWIRLING FLUIDIZED BED Satya Andika Putra; Novrinaldi Novrinaldi Novrinaldi
Widyariset Vol 6, No 2 (2020): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.6.2.2020.99-106

Abstract

Numerical and experimental studies have been carried out on the effect of inlet air number to the air velocity distribution in the drying chamber of the Swirling Fluidized Bed Dryer (SFBD). The main components of SFBD are a drying chamber, plenum chamber, center body, distributor, inlet air, heater, and blower. Numerical analysis was performed using the finite volume method on a three-dimensional model using computational fluid dynamic (CFD) software. An experimental study was carried out by measuring the air velocity at eight measurement points in the drying chamber. The results showed that using two inlet air produced a more uniform distribution of air velocity compared to one inlet air.
ANALISIS KANDUNGAN (AIR, ABU, DAN LOGAM BERAT) PADA KOPI BUBUK ASAL GAYO bhayu gita bhernama
Widyariset Vol 5, No 2 (2019): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.5.2.2019.87-94

Abstract

Gayo coffee is one type of arabica coffee originating from the Gayo plateau, Central Aceh district. Where Gayo coffee has a distinctive flavor, strong aroma and taste specifically. In the Gayo coffee processing process, it is inseparable from various kinds of contamination, so analysis needs to be done. Analysis was carried out on two coffee samples taken from two factories, namely factories A and B. Analysis carried out included analysis of water, ash, and metal content of ground coffee originating from Gayo. The analysis of metal content was carried out by using Atomic Absorbtion Spectroscopy (AAS). The test results showed that coffee A had a water content of 0.0397% and ash content 4% while coffee B had a water content of 0.01772% and ash content 4.3%. The test results of heavy metal within coffee A and B revealed that the contaminants of Cu, Hg, Pb and Zn metals existed. The coffee A contained Cu and Hg metal contamination with levels of 6.4945 and 0.0029 mg/Kg respectively. While, the coffee B contained Cu and Hg metal contamination with levels of 7.6120 and 0.0042 mg/Kg, respectively. The contamination of Pb and Zn within the coffee A and B were low and insignificant (0.001 mg/Kg). From the results of the analysis, it was found that the water, ash and metal content in coffee A and coffee B complies to the Indonesian National Standards (SNI) 01-3542-2004.
COMPARISON OF RAYLEIGH WAVE CHARACTERISTICS ON SUPERCONDUCTING GRAVIMETER AND SESIMOMETER LHZ RECORDINGS MARISKA NATALIA RANDE; Mahmud Yusuf; Alexander F. T Parera
Widyariset Vol 5, No 1 (2019): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.5.1.2019.11-20

Abstract

The vibrations of an earthquake can be properly recorded by the gravimeter. As a Gravimeter, Superconducting Gravimeter (SG) has a very high accuracy; slightly different with general gravimeter. Rayleigh wave is the wave with the largest amplitude in earthquake, so it will be clear on SG tape.  In this research, we use certain superconducting gravimeter (SG) and Seismometer LHZ, spread over several locations around the world; just to know more about Mw > 6 earthquake. Tidal value reduction were applied on SG’s recording in order  to get true gravity value. Then we did time-integral to get velocity and displacement. By using spectrogram function, we can display frequency of SG and LHZ. The amplitude of the Rayleigh wave recorded on the SG is smaller than that recorded on the LHZ and has signal correlation > 7.0. In any case of Rayleigh Global waves, SG is able to record clearly the phase of Rayleigh wave to R7 phase. While LHZ only records up to the R5 phase. The spectrograph analysis reinforces the differences in the viewing screens of SG and LHZ Rayleigh Global waves in the frequency domain, R7 recorded on SG has a frequency range of 0.002 Hz to 0.006 Hz. Based on the results of Rayleigh wave analysis on the SG record and its comparison with the LHZ record it can be concluded that SG has a high level of sensitivity and stable when recording Rayleigh waves.
DETEKSI TEPI UNTUK VALIDASI MODEL TIGA DIMENSI TULANG PANGGUL PADA PERENCANAAN DESAIN IMPLAN Talitha Asmaria; Rafidah Rahmi; Muhammad Satrio Utomo; Dhyah Annur; Daniel Panghihutan Malau; Muhamad Ikhlasul Amal; Ika Kartika
Widyariset Vol 6, No 1 (2020): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.6.1.2020.51-61

Abstract

In the process of implant design and fabrication planning, the anatomical background of human bone is an important aspect to determine the accuracy of implant design. To help in understanding the human bone anatomy, replicas of human bone can be reconstructed using three-dimensional (3D) printing technology. This study aims to validate the digital model of human bone and the imaging data of human bone in order to have an appropriate recommendation for designing the total hip replacement (THR). Achieved data from computed tomography scanning (CT-Scan) modality was deciphered to build the digital 3D model human bone. The bone and the digital 3D model of bone were captured to be two-dimensional(2D) data in the same dimension and processed using the algorithm of edge detection. The images from the edge detection process were processed for finding the similarity of the images. The percentage of similarity, precision, and  accuracy between the bone and the digital 3D model have been validated and can be used as a reference in the THR designs.
Kajian Pemanfaatan Eceng Gondok (Eichornia crassipes) Sebagai Pakan Ternak Itik Alabio (Anas platyrhynchos Borneo) Siska Fitriyanti
Widyariset Vol 5, No 2 (2019): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.5.2.2019.47-53

Abstract

An efficient feeding strategy is utilizing abundant and nutritious local resources for livestock. Fermented hyacinths can be used as a substitute feed for ducks, which are widely available in natureand still not well utilized. On the other hand, water hyacinth also has a fairly good nutritional content to serve as a ducks feed intake. The purpose of this study is to determine the effect of feed consisting of water hyacinth fermentation to the growth of Alabio ducks. The results obtained were feed with 75% concentration of fermented hyacinths giving the best result for Alabio duck growth when compared with duck given commercial feed.
REDUCE CO ON CAR BY USING ZEOLITE MIFTAH FARHANA; Budiyono Budiyono; Nikie Astorina Yunita Dewanti; Wahyu Bambang Widayatno
Widyariset Vol 6, No 2 (2020): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.6.2.2020.107-115

Abstract

The number of vehicles in Jakarta increased by 5.66% from 2016. Vehicles have the highest contribution to air pollution, which is 70% of other activities. The purpose of this study was to determine the reduction of CO with zeolite pellets. This type of research is a quasi-experimental design with a non-equivalent control group design pre-test post-test design. The emission test instrument uses the automotive gas analyzer HESBOHN, a tachometer to measure engine speed, laptops, and stopwatches. The material used is activated natural zeolite pellets. Data were analyzed by univariate in the form of CO adsorption power efficiency, average, minimum, and maximum. The variables used are pellet drying time (3 hours and 24 hours) and engine speed (idle and 1250 rpm). The result of CO adsorption power efficiency using the most optimal zeolite pellets is Pellet I with 3 hours drying at 1250 rpm by 52%. While the lowest yield is Pellet II with 24-hour drying at idle conditions of 22%. The most effective CO emission reduction is by using Pellet I at 1250 rpm.
Optimalisasi Lateks Tetesan Lanjut Menggunakan Berbagai Koagulan Anjuran Afrizal Vachlepi
Widyariset Vol 6, No 1 (2020): Widyariset
Publisher : Pusbindiklat - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/widyariset.6.1.2020.1-21

Abstract

Natural rubber latex will coagulate naturally about 4-6 hours after tapping. This coagulation will produce low quality rubber and inconsistent. In addition, latex will be easily lost by rain because long coagulation time, especially continuous latex droplet. The use of coagulant in the continuous latex droplet can reduce yield losses and improve quality. The purposes were to identify and study the effect of coagulants on the dry rubber content and technical quality of the rubber from continuous latex droplet of clone BPM 24. The treatments was type of coagulants consist of formic acid, pure liquid smoke, liquid smoke DS, liquid smoke DK and control (auto coagulation). Each treatment use 10 rubber tree of clone BPM 24. The parameters consists of dry rubber content, initial plasticity (Po), plasticity retention index (PRI), Mooney viscosity, viscosity stability index (SVI), volatile matter content and ash content. The quality will be analyzed statistically using the completely randomized design non factorial and will be compared with Indonesian National Standard 06-1903-2000 about Standard Indonesian Rubber (SIR). The results showed that the use of coagulant to continuous latex droplet had significant effect on PRI and Mooney viscosity of rubber. The best treatment was obtained liquid smoke DS which produce rubber with quality standards for Po 36, PRI 80.8, Mooney viscosity 68, SVI 4, ash content 0.27% and volatile matter content 0.48%. The coagulated natural rubber with liquid smoke DS can produce rubber with quality specifications SIR 20 grade CV 70.

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