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Mechanical Properties and Biodegradability of Bamboo and Sengon Wood Thin Sheets Reinforced Poly Latic Acid (PLA) Biocomposites) Sujito, S.; Munawaroh, Hanim; Purwandari, Endhah
Jurnal ILMU DASAR Vol 14 No 2 (2013)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (591.423 KB) | DOI: 10.19184/jid.v14i2.513

Abstract

Development of biocomposite materials based on natural fibers and environmentally friendly resins to replace composite materials made from plastic and synthetic fibers give the consideration that the biocomposite materials are environmentally friendly materials. In this paper, we discuss the synthesis and characterization of biocomposite materials using a combination of thin sheets of bamboo reinforcement and resin sengon and poly lactic acid (PLA). As controls were also carried out the synthesis and characterization of biocomposite material with a thin layer of reinforcement only sengon bamboo and wood. Characterization of tensile strength and modulus of elasticity of the material is done by using the Tensile Test Machine ASTM D 638. In the mean time, biodegradability of materials are observed made by the method of burial for 1-4 weeks. Tensile test results show that the biocomposite material reinforced with a thin sheet bamboo has a tensile strength and modulus of elasticity greater than that of the other biocomposite materials produced in this study. Meanwhile, biocomposite materials with thin layers of wood sengon reinforced easily biodegradable (dG = 13.21 ± 0.59)%, compared to a biocomposite material with a thin layer of bamboo reinforcement (dG = 10.69 ± 0.79)%. From these results it can be concluded that the composite material with a thin layer of bamboo boosters are more likely to be applied to replace metallic materials.Keywords: Biocomposites, tensile strength, elastic modulus, biodegradability, bamboo and sengon wood thin layer.
Optimasi Tekanan Deposisi dalam Simulasi Efisiensi Sel Surya Berbasis Material a-Si:H Purwandari, Endhah; Winata, Toto
GRADIEN : Jurnal Ilmiah MIPA Vol 8, No 1 (2012): (Januari 2012)
Publisher : Universitas Bengkulu

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Abstract

Perhitungan efisiensi konversi sel surya tipe persambungan p-i-n dengan berbasis material a-Si:H dilakukan berdasarkan simulasi perhitungan karakteristik I-V dari material. Dalam bentuk 1 dimensi, Persamaan Poisson dan Persamaan Kontinyuitas diselesaikan dengan menggunakan  Femlab Simulation. Data empirik optical band gap Eg pada variasi tekanan deposisi 0-500 mTorr,  yang diperoleh dalam penumbuhan a-Si;H menggunakan teknik HWC-VHF-PECVD, menjadi input kegiatan optimasi. Hasil simulasi menunjukkan terjadinya penurunan efisiensi dengan adanya kenaikan Eg. Efisiensi sel surya tertinggi sebesar 9,88% diperoleh pada tekanan deposisi a-Si:H sebesar 500 mTorr. Perhitungan efisiensi konversi sel surya tipe persambungan p-i-n dengan berbasis material a-Si:H dilakukan berdasarkan simulasi perhitungan karakteristik I-V dari material. Dalam bentuk 1 dimensi, Persamaan Poisson dan Persamaan Kontinyuitas diselesaikan dengan menggunakan  Femlab Simulation. Data empirik optical band gap Eg pada variasi tekanan deposisi 0-500 mTorr,  yang diperoleh dalam penumbuhan a-Si;H menggunakan teknik HWC-VHF-PECVD, menjadi input kegiatan optimasi. Hasil simulasi menunjukkan terjadinya penurunan efisiensi dengan adanya kenaikan Eg. Efisiensi sel surya tertinggi sebesar 9,88% diperoleh pada tekanan deposisi a-Si:H sebesar 500 mTorr.   
Study of A Phenomenon STT (Spin Transfer Torque) on the Material La0.7Sr0.3MnO3 Shaped Nanowire Using Micromagnetic Simulation Rohman, Lutfi; Musyarofah, L.; Purwandari, Endhah
Jurnal ILMU DASAR Vol 18 No 2 (2017)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1209.742 KB) | DOI: 10.19184/jid.v18i2.5911

Abstract

STT (Spin Transfer Torque) can be referred to as a process of manipulation and control of spin current in the field of spintronics. When the material is ferromagnetic nanowire La0.7Sr0.3MnO3injected currents will move the domain wall with accompanying changes of spin currents. In mikromagnetik simulation shows that the application is capable of producing flow velocity or pressure of domain wall in the direction of electron flow. The domain wall pressure generating magnetization changes with increasing current density occurs. To that end, the simulation research was done in order to obtain the effect of the injection of electric current to the magnetization of the material. This phenomenon is simulated by modeling the material into the 3D geometry. The greater the current density is given the domain wall velocity or pressure on the nanowire faster so that the magnetization process is also faster. Changes in the velocity of the fastest domain wall is obtained when the material is injected with a current density as well as M-t get a graph showing oscillation pattern that is denser when the current is increased. Furthermore, the total energy analysis with variations in size diameter of 10 nm, 20 nm and 30 nm. The results show that with increasing diameter, total energy tends to increase. Keywords: spin transfer torque, La0.7Sr0.3MnO3, magnetisation, domain wall, ferromagnetic
Efficiency Calculation Analysis of A-Si:H Solar Cells for Determination of Optimum Filament Temperature in Material Deposition Purwandari, Endhah; Winata, Toto
Jurnal ILMU DASAR Vol 14 No 1 (2013)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (726.416 KB) | DOI: 10.19184/jid.v14i1.478

Abstract

Solar cell efficiency as a function of the energy gap has been simulated by calculating the output current characteristics of the devices based on the distribution of charge carriers, obtained from the solution of the Poisson equation and the Continuity equation. The hydrogenated amorphous silicon (a-Si:H) based solar cell, has simulated in the form of one-dimensional single junction p/i/n. The junction structure of a-SiC:H/a-Si:H/a-Si:H designed have the thickness of 0,015 μm/0,550 μm/0,030 μm, respectively. For simulation, the energy gap has considered constant in the p and n layers, whereas the i layer varies according to the empirical data of energy gap obtained from the deposition parameters of filament temperature. Simulations performed using the finite element method supported by FEMLAB software. Based on simulation results, obtained the highest efficiency of 9.35% corresponds to the lowest energy gap data of 1.706 eV for layer i. This appropriates to the filament temperature of 800oC and subsequently used as the optimum deposition parameters of the material. Keyword: Energy gap, efficiency, FEM, solar cell, hydrogenated amorphous silicon
Simulation of I-V Characteristics of Si Diode at Difference Operating Temperature:Effect of Ionized Impurity Scattering Arofah, Siti Lailatul; Purwandari, Endhah; Supriyanto, Edy
UNEJ e-Proceeding 2016: Proceeding The 1st International Basic Science Conference
Publisher : UPT Penerbitan Universitas Jember

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Abstract

The usage quality of Si Diode was influenced by the operating temperature. The increment of temperature caused the increased number of ionized impurities. Coulomb interaction between the impurities and the local charge carrier caused the scattering on the impurity. Furthermore, this scattering causes changes in the velocity and mobility of charge carriers. This gives an effect on the distribution of charge carriers, causing changes in the diffusion current density. In this paper, we perform the I-V characteristic of Si diode, simulated in two dimensional structure. Several temperatures (200K-473K) and also the charge carrier mobility were observed as the input parameter of the equation modelled. The simulation results show that the value of current density diffusion of Si Diodes was maximum at temperature of 200K and decreasing at a higher temperature of 473K.
Simulation of Solar Cell Diode I-V Characteristics Using Finite Element Methode: Influence of p- Layer Thickness Fatma, Greta Andika; Purwandari, Endhah; Supriyanto, Edy
UNEJ e-Proceeding 2016: Proceeding The 1st International Basic Science Conference
Publisher : UPT Penerbitan Universitas Jember

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Abstract

Characteristic of I-V is a key parameter of describing the performance of solar cell diode, specially for Silicon material. One of the effort to get its higher performance can be conducted by investigating the effect of the thickness of p-layer. The thickness becomes important factor because of its function as windows layer, which will determine the number of generation factor, appropiate to the charge carrier producing. Here, we explore them by using computer program, applying finite element methode as the numerical simulation. The geometry of the diode was simulated in one dimensional structure, where the thickness of p-layer varied from 0,7 μm to 1,5 μm, while the n-layer was fixed at a thickness of 3,5 μm. The result showed that the optimum parameters has come out to achieve the best performance of this type of solar cell.
Study of Phenomenon STT (Spin Transfer Torque) on Permalloy NiFe Material Shaped Nanowire Using Micromagnetic Simulation Ni’mah, Khiptiatun; Rohman, Lutfi; Purwandari, Endhah
Computational And Experimental Research In Materials And Renewable Energy Vol 2 No 1 (2019): May
Publisher : Physics Department, Faculty of Mathematics and Natural Sciences, University of Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/cerimre.v2i1.20555

Abstract

STT is a process of controlling the spin currents in spintronic. This simulation aims to know the properties of NiFe permalloy materials' properties by studying STT phenomenon-shaped nanowire that can be applied in storage devices, like MRAM. The material's magnetic properties include magnetization value, energy in the ferromagnetic system, and the speed of the domain wall movement, obtained by injecting the electric current density through a micromagnetic simulation using the NMAG program. This simulation's result is that the domain wall's position will shift faster along the nanowire when we inject current density to the nanowire. Current density injection will produce a domain wall pressure on the domain structure, resulting in a change in the material's magnetization value. The graph of magnetization relation to time (M-t), shown along with the increasing electric current density, we obtain oscillation magnetization change will increase. The larger the given diameter, the total energy generated will increase, demagnetization energy tends to be greater than the energy exchange. The greater the polarization of the material provided at the same diameter, the speed of the domain wall movement will be greater too.
Built in Potential of a-Si:H Based p-i-n Solar Cell at Different Energy Gap of Intrinsic Layer Yuniarsih, Rahayu Setyo; Purwandari, Endhah; Misto, Misto; Supriyanto, Edi; Supriyadi, Supriyadi
Computational And Experimental Research In Materials And Renewable Energy Vol 1 No 1 (2018): November
Publisher : Physics Department, Faculty of Mathematics and Natural Sciences, University of Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/cerimre.v1i1.19547

Abstract

The photovoltaic process inside a solar cell can be described using the distribution of electrostatic potential in the material. In this paper, the magnitude of the electrostatic potential of the solar cell for the p-i-n junction type is analyzed as the built in potential due to the diffusion activity of electrons and holes. The magnitude of the electrostatic potential is obtained by solving the Poisson and Continuity equations, which are applied to a-Si: H based materials. The difference in built in potential at the p-i and i-n junctions is obtained as a function of the energy gap of the intrinsic layer.
Density of Liquid Lead as Function of Temperature and Pressure Based on the Molecular Dynamics Method Imanullah, Muhammad Abdul Bashar; Arkundato, Artoto; Purwandari, Endhah
Computational And Experimental Research In Materials And Renewable Energy Vol 1 No 1 (2018): November
Publisher : Physics Department, Faculty of Mathematics and Natural Sciences, University of Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/cerimre.v1i1.19541

Abstract

Simulation research has been carried out to obtain the formula for mass density of liquid lead as a function of temperature and pressure. The simulation method used is the molecular dynamics method. The potential energy used in the simulation is the Morse potential. From the simulation, it is found that the relationship between the mass density of liquid lead and temperature and pressure can be expressed in the equation pPb = 11233 - 0,9217 x T for pressure 1 – 5 atm and pPb = 11233 x 0,9213 x T for pressure 7 atm in units kg/m.
Biobriket Arang Sekam Padi sebagai Sumber Energi Terbarukan untuk Aplikasi Pandai Besi Maulina, Wenny; Sulistiyo, Yudi Aris; Purwandari, Endhah
Warta Pengabdian Vol 14 No 4 (2020): Warta Pengabdian
Publisher : LP2M Universitas Jember

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Abstract

Sumber energi terbarukan berbasis biomassa merupakan sumber daya potensial menggantikan kayu bakar atau batu bara yang persediannya semakin menipis sebagai bahan bakar industri pandai besi. Salah satu potensi biomassa adalah sekam padi yang dapat dijadikan bahan baku pembuatan biobriket. Oleh karena itu, tujuan pelaksanaan kegiatan ini adalah untuk menghasilkan biobriket arang sekam padi sebagai bahan bakar alternatif pada industri pandai besi. Kegiatan ini dilakukan dalam beberapa tahapan yaitu 1) pembuatan alat pencetak yang mampu menghasilkan 4 buah biobriket sekali produksi, 2) pembuatan biobriket arang sekam dan diuji sifat dan karakteristiknya, dan 3) pelatihan pembuatan dan penerapan langsung biobriket untuk proses pemanasan besi pada industri pandai besi. Karakteristik biobriket arang sekam diuji berdasarkan nilai kapasitas kalor, kadar air, kadar abu, dan volatile matter berturut–turut adalah 3709,47 kalori per gram; 4,27%; 3,93%; dan 59,20%. Hasil pengujian pembakaran secara langsung menghasilkan nyala api berwarna biru dengan suhu berkisar 533,8 – 704,3 oC. Hasil biobriket telah diimplementasikan dan mampu diterima untuk menggantikan kayu bakar yang selama ini digunakan pada sentra pengrajin pandai besi di Desa Suger Kidul, Kec. Jelbuk, Kab. Jember.