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SINTESIS DAN SIFAT MEKANIK BIOKOMPOSIT SERAT HELICONIA-POLIESTER Maddu, Akhiruddin
Jurnal Biofisika Vol. 8 No. 2 (2012): Jurnal Biofisika
Publisher : Jurnal Biofisika

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Abstract

In this study, polyester-fiber heliconia biocomposites has been created and tested on its mechanical properties. Biocomposites was manufactured begins by separating the fibers.  it  consists  of  three  stages,  namely  chlorization,  alkaline  leaching  and extraction.  After  that,  the  manufacture  of  composites  made  with  Hand  Lay-up techniques.  Three  samples  with  variations in  fiber content,  ie without  the addition of fiber,  0.54  g  and  2.08  g  fiber.  Characterization  of  samples  includes  tensile  test, hardness,  and  impact.  The test results known that  the  tensile  strength  and  hardness increased  with  increasing  the  amount  of fiber  heliconia.  Impact  test  shows  sample values optimum working temperature is 10°C
FABRICATION AND CHARACTERIZATION DYE-SENSITIZED SOLAR CELL BASED ON TIO2/SNO2 COMPOSIT ELECTRODE AND POLYMER ELECTROLITE Irmansyah, Irmansyah; Maddu, Akhiruddin; Zuhri, Mahfuddin
Jurnal ILMU DASAR Vol 9 No 2 (2008)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

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Abstract

A solid-state dye-sensitized solar cell based on TiO2/SnO2 composite electrode and polyethylene glycol (PEG) based electrolyte has been fabricated. The solar cell was formed in sandwich structure, which two electrodes sandwiching polymer electrolyte containing a redox couple (I-/I3-). One of the electrode was TiO2/SnO2 composite layer on TCO (transparent conducting oxide) coated glass substrate which sensitized with Ruthenium complex dye as electron donor, and the other electrode was a carbon sheet as a counter electrode. Active area of solar cell was 1.5 cm x 1 cmm. The solar cell was tested by irradiation with mercury lamp of 400 Watt with intensity of 30 mW/cm2 at a distance of 30 cm and sunlight with intensity of 36 mW/cm2. The cell tested with mercury lamp result in an open circuit voltage (VOC) of 420 mV, short circuit current (ISC) of 52 ?A, maximum power (Pmax) of 10.4 ?W, fill factor (FF) of 48% and energy conversion (?) of 0.023 %. On the other hand, the cell tested with sunlight source result in VOC=480 mV, ISC=48?A, Pmax=12.6 ?W, FF=55% and ?=0.023%.
KARAKTERISASI OPTIK DAN STRUKTUR KRISTAL LiTaO3 PADA SUBSTRAT SILIKON [Si(111)] TIPE-n/n+ Sani, Yulia; Ukhtiningsih, Ira; Herawan, Bambang; Maddu, Akhiruddin; Irzaman, -
Jurnal Spektra Vol 16, No 2 (2015): Spektra: Jurnal Fisika dan Aplikasinya
Publisher : Jurnal Spektra

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Abstract

AbstrakTelah berhasil dibuat film LiTaO3 pada substrat silikon [Si(111)] tipe-n/n+ dengan variasi suhu annealing selama 8 jam pada suhu  600 oC, dan 625 oC. Metode yang digunakan yaitu Chemical Solution Deposition (CSD) dengan spin coating berkecepatan putar 3000 rpm selama 30 detik dalam kelarutan 1 M. Analisis energi band gap menggunakan metode Tauc Plot diperoleh hasil nilai  2.58 dan 2.57 eV. Hasil analisis XRD untuk film LiTaO3 pada suhu annealing 600 0C menunjukkan bahwa struktur kristalnya membentuk hexagonal dengan parameter kisi a=b=5.199Å dan c=13.890Å . Hasil uji optiknya dapat mengabsorbsi spektrum Inframerah dekat dengan transisi tidak langsung, dan termasuk material semikonduktor.Kata kunci : Energi gap, LiTaO3, sifat optik, silikon tipe n/n+, XRD AbstractLiTaO3 films had been successfully deposited on the substrate of n/n+-type Silicon [Si(111)] wich temperature variant for 8 hours at temperature of 600 oC, and 625 oC. The method can be used Chemical Solution Deposition (CSD) and spin coating with rotational speed 3000 rpm for 30 seconds and 1 M solubility. Analysis of the band gap energy using Tauc Plot method produce results of 2.58 eV and 2.57 eV. The result of XRD Crystal structure analysis showed that LiTaO3 film annealed at 600 oC show a hexagonal structure  with lattice parameters of a = b = 5.199Å and c = 13.890Å. The result of optical characterization has shown that LiTaO3 can absorb near infrared spectrum through indirect transition and indicates that LiTaO3 films is semiconductor  materials.Keywords: band gap energy, LiTaO3, optical property, n/n+-type Silicon [Si(111)], XRD.
Karakteristik Optik Film Hibrid ZnO/Klorofil yang Termodifikasi Logam Seng (Zn) dan Tembaga (Cu) Maddu, Akhiruddin; Gareso, Paulus P; Sugianto, .
Omega: Jurnal Fisika dan Pendidikan Fisika Vol 1, No 1 (2015)
Publisher : Omega: Jurnal Fisika dan Pendidikan Fisika

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Abstract

Film hibrid yang merupakan perpaduan antara semikonduktor ZnO dan dye klorofil yang telah disintesis dengan menggunakan metode spin coating dan ZnO dengan dengan metode casting. Hasil karakterisasi optik didapatkan bahwa film ZnO menyerap kuat pada panjang gelombang 367 nm. Hasil kombinasi film ZnO/klorofil hasil dari eksperimen memperlihatkan bahwa film ZnO mengalami pelebaran puncakdari 330 nm sampai 500 nm untuk penambahan klorofil, pada penambahan Znfoefitin terjadi dua pelebaran puncak yaitu dari 330 nm sampai 388 nm dan dari 400 nm sampai 511 nm, akan tetapi pelebaran ini tidak terlalu signifikan dibandingkan dengan penambahan klorofil. Untuk kombinasi antara ZnO dengan Cu-feofitin, terjadii pelebaran puncak yang sangat signifikan yaitu dari 300 nm sampai 600 nm.
The use of Red Cabbage’s anthocyanine extract as a photosensitizer on a Dye-Sensitized Nanocrystalline TiO2 Solar Cell Maddu, Akhiruddin; Zuhri, Mahfuddin; Irmansyah, Irmansyah
Makara Journal of Technology Vol 11, No 2 (2007)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (148.146 KB) | DOI: 10.7454/mst.v11i2.131

Abstract

A solid-state dye-sensitized nanocrystalline TiO2 solar cell utilizing anthocyanin extract form red cabbage as photosensitizer was fabricated. The solar cell was formed in sandwich structure, which two electrodes sandwiching polymer electrolyte containing a redox couple (I-/I3-). One of the electrodes, namely working electrode, TiO2 layer on TCO (transparent conducting oxide) coated glass substrate was sensitized with anthocyanin dye as electron donor in the system. Another electrode was a carbon sheet as a counter electrode. Gel electrolyte based on PEG (polyethylene glycol) containing a redox couple (I-/I3-) used instead of liquid electrolyte in this photoelectrochemical cell. Two fabricated cells have an active area of 1 cm2 were soaked with anthocyanine dye for 1 hr and 24 hrs, respectively. The cells were tested by irradiation with halogen lamp of 24 Watt with intensity 4 mW/cm2 at a distance 30 cm. The testing results of the cells show an ideal I-V characteristic with output parameters: open circuit voltage (VOC) of 500 mV, short circuit current (ISC) of 5,6 μA and 7,2 μA for each cells, fill factor (FF) of 48% for both cells, energy conversion (η) of 0.023 % and 0,055 % for the cells with 1 hr and 24 hrs dye soaked, respectively.
Development of Fiber-Optic Humidity Sensor Probe with Gelatin Cladding Maddu, Akhiruddin; Modjahidin, Kun; Sardy, Sar; Zain, Hamdani
Makara Journal of Technology Vol 10, No 1 (2006)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (161.549 KB) | DOI: 10.7454/mst.v10i1.111

Abstract

Humidity sensor based on optical fiber with gelatin cladding has been developed. In this humidity sensor probe, the origin cladding of optical fiber is replaced by gelatin coating as humidity sensitive cladding. Testing of the optical fiber sensor probe was conducted by measuring of light intensity transmitted on the optical fiber probe for each variation of different humidity treatments. Response of the optical fiber sensor probe measured from 42%RH to 99%RH, the results show an optical transmission curve varied with relative humidity (RH). Optical transmission in the optical fiber probe increase with RH value at a specific wavelength range, that is from green to red spectrum bands (500 nm - 700 nm), where a significant variation from 600 nm to 650 nm in yellow to red spectrum bands. Wavelength where is a maximum intensity of optical transmission occurs at 610 nm. Therefore, the optical fiber humidity sensor probe could response humidity form 42%RH to 99%RH with the best response in humidity range of 60%RH to 72%RH that is have a good  linearity and sensitivity
DETERMINING IMAGE OPACITY IN BROILER RESPIRATORY RADIOGRAPHIC USING IMAGEJ AND ANSEL ADAM’S ZONE SYSTEM Wirahadikesuma, Ikhwan; Santoso, Koekoeh; Maheshwari, Hera; Maddu, Akhiruddin
Jurnal Riset Veteriner Indonesia (Journal of The Indonesian Veterinary Research) VOLUME 4 No. 1, JANUARY 2020
Publisher : Hasanuddin University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20956/jrvi.v4i1.8431

Abstract

The diagnosis of diseases of the respiratory, lung, and air sacs generally uses radiographic images by radiologists. Therefore, the results are very subjective, causing differences in the interpretation and diagnosis among different radiologists. A radiographic image reading needs to be made in the form of a simple, fast, and accurate algorithm. The study aimed to reduce subjectivity and be easily carried out by radiology medical personnel, especially veterinarians. This study carried out density measurements by image processing using ImageJ software on 14 radiographic images of broiler chickens. Furthermore, the density value is associated with the Ansel Adam's - grayscale system to determine the opacity of respiratory tract tissues/organs, which were previously inhaled by one of them with chitosan-iopamidol nanoparticles using a nebulizer. The results of density measurements for the category of opacity in radiographic images are that seven spot areas lead brighter (radiopaque) only in chickens that are inhaled mist maker of chitosan-iopamidol nanoparticles. Then the determination of the value range is obtained average value on two ventrodorsal radiographic images, which are inhaled by mist maker of chitosan-iopamidol nanoparticles and chitosan nanoparticle compressor. The conclusion of this study was only in chickens that were infested with mist maker chitosan-iopamidol, whose radiographic image had a radiopaque spot and middle-value area. 
PEMANFAATAN KARBON AKTIF DARI BAMBU SEBAGAI ELEKTRODA SUPERKAPASITOR Tumimomor, Farly; Maddu, Akhiruddin; Pari, Gustan
JURNAL ILMIAH SAINS Volume 17 Nomor 1, April 2017
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.17.1.2017.15802

Abstract

PEMANFAATAN KARBON AKTIF DARI BAMBU SEBAGAI ELEKTRODA SUPERKAPASITOR ABSTRAKPada penelitian ini, karbon aktif berbasis bambu telah digunakan untuk pembuatan superkapasitor. Uji daya jerap iodin dilakukan untuk mengukur tingkat serapan pori sampel karbon aktif yang ukurannya relatif kecil (mikropori). Karakteristik bahan karbon aktif yang meliputi struktur kristal dan morfologi permukaannya diuji dengan menggunakan SEM dan XRD. Bahan elektroda dengan komposisi (Karbon aktif : PVDF = 9:1 (b/b)), kolektor arus dan separator telah dirangkai untuk diuji kinerjanya sebagai perangkat penyimpanan muatan listrik. Metode siklik voltametri digunakan untuk melihat kinerja perangkat superkapasitor dengan mengukur nilai kapasitansi spesifik berdasarkan kurva voltammogram. Berdasarkan hasil perhitungan nilai kapasitansi spesifik diperoleh nilai kapasitansi spesifik tertinggi pada superkapasitor dengan elektroda bambu yang diaktivasi dengan steam 50 mL/bar yaitu sebesar  59.50 F.Kata kunci: Karbon aktif bambu, siklik voltametri, kapasitansi spesifik, superkapasitor.  UTILIZATION OF BAMBOO BASED ACTIVATED CARBON AS SUPERCAPACITOR ELECTRODE ABSTRACT In this study, bamboo based activated carbon has been used for fabrication of supercapacitors. Iodine absorption test is performed to measured absorption level porous activated carbon sample size is relatively small (microporous). Characteristics of the activated carbon material covering the surface morphology and structure were tested using SEM and XRD. Electrode materials with composition (Activated charcoal: PVDF = 9: 1 (w / w)), the current collector and separator has been assembled to be tested its performance as an electrical charge storage device. The test results by cyclic voltammetry method was to look at the performance supercapacitor devices at once to obtain the value of the capacitance curve obtained voltammograms. Based on the results of the calculation of the capacitance, the highest capacitance values obtained in the supercapacitor with activated carbon electrodes in bamboo steam 50 mL / bar with a capacitance value is 59.50 F / g.Keywords: Bamboo activated carbon, cyclic voltammetry, the specific capacitance, supercapacitor.
KARAKTERISASI OPTIK DAN STRUKTUR KRISTAL LiTaO3 PADA SUBSTRAT SILIKON [Si(111)] TIPE-n/n+ Sani, Yulia; Ukhtiningsih, Ira; Herawan, Bambang; Maddu, Akhiruddin; Irzaman, Irzaman
Spektra: Jurnal Fisika dan Aplikasinya Vol 16 No 2 (2015): SPEKTRA, Volume 16 Nomor 2, Oktober 2015
Publisher : Program Studi Fisika Universitas Negeri Jakarta

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Abstract

Abstrak Telah berhasil dibuat film LiTaO3 pada substrat silikon [Si(111)] tipe-n/n+ dengan variasi suhu annealing selama 8 jam pada suhu 600 oC, dan 625 oC. Metode yang digunakan yaitu Chemical Solution Deposition (CSD) dengan spin coating berkecepatan putar 3000 rpm selama 30 detik dalam kelarutan 1 M. Analisis energi band gap menggunakan metode Tauc Plot diperoleh hasil nilai 2.58 dan 2.57 eV. Hasil analisis XRD untuk film LiTaO3 pada suhu annealing 600 0C menunjukkan bahwa struktur kristalnya membentuk hexagonal dengan parameter kisi a=b=5.199Å dan c=13.890Å . Hasil uji optiknya dapat mengabsorbsi spektrum Inframerah dekat dengan transisi tidak langsung, dan termasuk material semikonduktor. Kata kunci : Energi gap, LiTaO3, sifat optik, silikon tipe n/n+, XRD Abstract LiTaO3 films had been successfully deposited on the substrate of n/n+-type Silicon [Si(111)] wich temperature variant for 8 hours at temperature of 600 oC, and 625 oC. The method can be used Chemical Solution Deposition (CSD) and spin coating with rotational speed 3000 rpm for 30 seconds and 1 M solubility. Analysis of the band gap energy using Tauc Plot method produce results of 2.58 eV and 2.57 eV. The result of XRD Crystal structure analysis showed that LiTaO3 film annealed at 600 oC show a hexagonal structure with lattice parameters of a = b = 5.199Å and c = 13.890Å. The result of optical characterization has shown that LiTaO3 can absorb near infrared spectrum through indirect transition and indicates that LiTaO3 films is semiconductor materials. Keywords: band gap energy, LiTaO3, optical property, n/n+-type Silicon [Si(111)], XRD
Immobilization of Glucose Oxidase on Modified-Carbon-Paste-Electrodes for Microfuel Cell Ambarsari, Laksmi; Setyawati, Inda; Kurniasih, Rini; Kurniatin, Popi Asri; Maddu, Akhiruddin
Indonesian Journal of Chemistry Vol 16, No 1 (2016)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (368.241 KB) | DOI: 10.22146/ijc.21183

Abstract

Glucose oxidase (GOx) is being developed for many applications such as an implantable fuel cell, due to its attractive property of operating under physiological conditions. This study reports the functional immobilization of glucose oxidase onto polyaniline-nanofiber-modified-carbon-paste-electrodes (GOx/MCPE) as bioanodes in fuel cell applications. In particular, GOx is immobilized onto the electrode surface via a linker molecule (glutaraldehyde). Polyaniline, synthesized by the interfacial polymerization method, produces a morphological form of nanofibers (100-120 nm) which have good conductivity. The performance of the polyaniline-modified-carbon-paste-electrode (MCPE) was better than the carbon- paste-electrode (CPE) alone. The optimal pH and temperature of the GOx/MCPE were 4.5 (in 100 mM acetate buffer) and 65 °C, respectively. The GOx/MCPE exhibit high catalytic performances (activation energy 16.4 kJ mol-1), have a high affinity for glucose (Km value 37.79 µM) and can have a maximum current (Imax) of 3.95 mA. The sensitivity of the bioelectrode also was high at 57.79 mA mM-1 cm-2.