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"Polyaniline (PANi) telah sintesis melalui proses polimerisasi melalui penggunaan Ammonium Persulphate (APS) sebagai initiator pada suhu kamar. Selama proses polimerisasi, terjadi peningkatan nilai viskositas cairan polimer dari 436 mPa.s menjadi 1601 mPa.s. Selama proses, juga teramati peningkatan ukuran partikel. Kedua indicator tersebut, terkait dengan terbentuknya rantai molekul polimer ketika berlangsungnya proses polimerisasi. Terbentuknya PANi dapat dipastikan melalui spectrum FTIR sampel hasil sintesis. Hasil penelitian juga menunjukkan, terjadi peningkatan nilai konduktivitas listrik PANi setelah polianilin basa emeraldin (PANi-EB) didop dengan asam lemah. Hasil pengukuran menunjukkan bahwa konduktivitas listrik PANi-EB meningkat dari 50 μS.cm-1 menjadi 1260 μS.cm-1 setelah penambahan asam lemah H3PO4 and 1480 μS.cm-1 setelah penambahan C2H4O2. Disimpulkan bahwa PANi konduktif telah berhasil disintesis melalui proses polimerisasi.

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Polyanilines (PANIs) have been synthesized by the polymerization process utilized Ammonium Persulphate as an initiator at room temperature. The complete reaction of polymerization process was indicated by increasing viscosity from 436 mPa.s to 1601 mPa.s. An increase in electrical conductivity of PANi occurred after polyaniline emeraldine base (PANi-EB) doped with weak acids. It is shown that the electrical conductivity of PANi increases from 50 μS.cm-1 to 1260 μS.cm-1 and 1480 μS.cm-1 after doped with weak acids of H3PO4 and C2H4O2 respectively. It is concluded that the conductive PANi has successfully synthesized by the polymerization process."

"ABSTRAKSelama lebih dari 100 tahun, steel core digunakan sebagai konduktor padakabel untuk memberikan ketahanan terhadap kekuatan tarik, mengurangi defleksike ground (sag) serta mampu mengakomodir rentang antar tiang yang cukuppanjang. Dalam perkembangannya, seiring dengan permintaan akan kebutuhanpeningkatan effisiensi dan kapasitas, telah ditemukan beberapa type darikonduktor dalam beberapa dekade terakhir. Type dari konduktor yang telahdikembangkan tersebut diklaim mampu, meningkatkan electrical capacity padatemperatur operasi yang tinggi dengan tingkat losses yang rendah. Konduktor inidiistilahkan dengan ACCC (Aluminum Conductor Composite Core) yang memilikiketahanan terhadap temperatur tinggi. Pada penelitian ini sifat mekanik daricomposite core ini diukur pada range temperatur 100 - 300°C selama 120 menituntuk tiap sampel dengan kenaikan temperatur tiap 50°C. Di atas temperatur150°C, terjadi penurunan sifat mekanik dari composite core akibat perubahanstruktur mikro dan berkurangnya sifat adhesive pada bagian interface. Sifatmekanik dari composite core ini menjadi bagian yang menentukan dalamaplikasinya untuk mendapatkan konduktor yang tahan terhadap temperatur tinggidengan defleksi yang cukup kecil.

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ABSTRACTFor over one hundred years steel core strands have been used to increase thetensile strength and reduce thermal sag of bare overhead conductors toaccommodate longer spans between fewer or shorter structures. As demand forelectricity continues to grow, increasing the capacity and efficiency of existing orproposed transmission lines is becoming increasingly important. A new type ofconductor that have been developed are claimed to be capable, increasing theelectrical capacity at a high operating temperature with the loss rate is low. Theconductor is designated ACCC (Aluminum Conductor Composite Core) which isresistant to high temperature. In this research, the high temperature strength of theconductor is assessed. The strength of the composite core measured at 100°C to300°C within 120 minutes by 50°C increment. Above 150°C, the strength droppeddue to the phase change in the matrix which degraded the elastic properties anddecrease interface adhesion. The mechanical properties of the composite corehighlight the potential for the use of composite materials to produce overheadconductors with low sag at high temperatures"

"Transmitansi dan reflektansi merupakan dua metode pengukuran yang umum digunakan untuk melakukan investigasi terhadap sifat kimia zat cair berdasarkan spektrum optis. Dalam kasus karakterisasi madu, penelitian ini dilakukan untuk menunjukkan perbandingan dari kedua metode pengukuran tersebut pada prediksi parameter kualitas madu seperti Total Soluble Solids (TSS), pH, dan Electrical Conductivity (EC) berdasarkan sistem pencitraan hiperspektral. Sistem terdiri atas kamera hiperspektral SPECIM FX10 dengan 224 kanal (400-1000 nm), tiga buah lampu halogen 150 W, sebuah kotak diffuser cahaya, sebuah slider bermotor, dan sebuah PC. Kemudian, algoritma Partial Least Square-Support Vector Regression (PLS-SVR) dengan Gaussian Kernel untuk memprediksi nilai referensi berdasarkan spektrum transmitansi dan reflektansi yang telah didapatkan. Performa dari setiap metode diuji dengan tenfold Cross Validation, yang akan mengelompokkan data menjadi 10 partisi. Sampel diperoleh dari 30 varian madu dengan warna yang bervariasi, ditempatkan pada cawan Petri berdiameter 5 cm dengan volume 5 mL. Performa dari setiap metode diukur berdasarkan nilai koefisien determinasi R2 dan Root Mean Square Error (RMSE). Evaluasi model yang diperoleh dari metode transmitansi menghasilkan R2 sebesar 0,75, 0,87, dan 0,83, RMSE sebesar 3,62, 0,03, dan 0,01 untuk prediksi nilai TSS, pH, dan EC berdasarkan testing data. Untuk prediksi parameter yang sama, metode reflektansi menghasilkan R2 sebesar 0,82, 0,91, dan 0,94, RMSPE dan 2,72, 0,02, and 4,98×10-3 berdasarkan testing data. Pada penelitian ini, metode reflektansi memiliki kinerja yang lebih baik daripada metode transmitansi dalam prediksi parameter kualitas madu.

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Transmittance and reflectance modes are the two most common measurement methods used for investigating liquid chemical properties based on optical spectrum. In the case of honey characterization, this research performed to show a comparison between both measurement methods to predict honey quality parameters, such as Total Soluble Solids (TSS), pH, and Electrical Conductivity (EC) based on the Vis-NIR hyperspectral imaging system. The system consists of Specim FX10 hyperspectral camera with 224 bands (400-1000 nm), three 150 W halogen lamps, a light diffuser box, a motorized slider, and a PC. Then, Partial Least Square-Support Vector Regression (PLS-SVR) with Gaussian Kernel algorithm applied to predict reference values based on the acquired transmittance and reflectance spectrum. Performance of each method tested by tenfold Cross Validation, which randomly grouping the dataset into ten partitions. Samples is obtained from 30 different honey variant with varied colors, placed in 5 cm diameter Petri dishes at 5 mL volume. Performance of each tmethod measured by coefficient of determination R2 and a Root Mean Square Error (RMSE) score. Model evaluation of transmittance mode results in R2 of 0.75, 0.87, and 0.83, RMSE of 3.62, 0.03, and 0.01 for TSS content pH, and EC prediction based on testing data. For similar predicted parameters, reflectance mode results in R2 of 0.82, 0.91, and 0.94, RMSPE of 2.72, 0.02, and 4,98×10-3 based on testing data. In this research, reflectance mode performs better than transmittance mode in the prediction of honey quality parameters."

"Termoelektrik adalah fenomena yang berhubungan dengan perubahan temperatur dan beda potensial. Banyaknya aplikasi dari termoelektrik mendorong penelitian tentang material termoelektrik di Departemen Fisika Universitas Indonesia. Performa material termoelektrik dapat dihitung menggunakan nilai figure of merit. Untuk menghitungnya dibutuhkan nilai koefisien seebeck, konduktivitas listrik, dan konduktivitas panas. Seluruh nilai tersebut bisa didapatkan melalui sistem karakterisasi material termoelektrik yang memiliki sistem pengendalian temperatur dan arus listrik di dalamnya. Sumber arus dibuat memanfaatkan DAC dan rangkaian op-amp. Sumber arus yang digunakan memiliki tiga rentang arus yang dapat digunakan yaitu, 0-50 mA, 0-10 mA, dan 0-5 mA. Untuk menjaga temperatur probe dingin di suhu ruang, dilakukan pengendalian menggunakan metode Direct Synthesis dengan nilai Kc = 1,24 dan 𝜏𝐼 = 310. Sementara pada pengendalian temperatur pemanas, digunakan metode IMC dengan nilai Kc = 1,238, 𝜏𝐼 = 1122s dan , 𝜏𝐷 = 38,574s.

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Thermoelectric is a phenomenon related to temperature changes and potential differences. Many applications of thermoelectrics encourage research on thermoelectric materials in the Department of Physics Universitas Indonesia. Thermoelectric material performance can be calculated using a reasonable number value. To calculate the required values for the seebeck coefficient, electrical conductivity, and heat conductivity. All of these values can be obtained through the thermoelectric material characterization system which has a temperature and electric current control system in it. Electric current source is made using DAC and op-amp circuit. This electric current source has three ranges of current that can be used, namely, 0-50 mA, 0-10 mA, and 0-5 mA. To keep the temperature of the cold probe at room temperature, control was carried out using the Direct Synthesis method with a value of Kc = 1,24 and 𝜏𝐼 = 310. While at heating temperature, the IMC method was used with a value of Kc = 1,238, 𝜏𝐼 = 1122s dan , 𝜏𝐷 = 38,574s."

"Doping yttrium ions, Y3+ into ZrO2 produced Yttria-Stabilized Zirconia, YSZ. Various amount of yttrium ions could provide different ionic conductivity. This research investigated electrical conductivity of various YSZ composition, i.e., 4.5; 8.0 and 10% mol yttrium in ZrO2. The ZrO2 powder used was synthesized from zircon sand, a side product of tin mining plant, Bangka Island, Indonesia. Structural investigation on the prepared YSZ found that yttrium ion doping has changed the crystal structure of ZrO2 from monoclinic to cubic, even though the monoclinic and tetragonal are also still exist. The Y3+ doping changed the cell parameter of ZrO2 crystal. It indicates that the Y3+ entered into the ZrO2 structure and produced vacancy sites. The highest ionic conductivity is provided by 8% mol Yttrium doping or 8YSZ, i.e., 2.74×10-4 S.cm-1 at 700oC with an activation energy of 0.741 eV."

"Busbar merupakan komponen penting dalam menghasilkan daya untuk motor listrik menggerakkan kendaraan listrik. Adanya kebutuhan busbar dengan karakteristik ringan, konduktivitas listrik baik, konduktivitas termal yang baik dan biaya perawatan murah. Oleh karena itu dilakukannya manufaktur busbar bimetal Al-Cu dengan metode friction stir welding (FSW). Material yang digunakan pada penelitian ini adalah aluminum paduan seri 6061 dan tembaga murni dengan tebal 6 mm. Tool FSW menggunakan material high speed steel dengan pin berbentuk silinder lurus. Proses FSW dilakukan dengan variasi kecepatan putaran tool 1000 rpm dan 1200 rpm dan sudut kemiringan tool 1 derajat dan 3 derajat. Pada daerah stir zone struktur mirip komposit Al-Cu terbentuk dengan partikel tembaga berada di dalam matrik aluminum. Dari uji kekerasan vickers didapatkan nilai kekerasan tertinggi sebesar 220,5 HV pada daerah TMAZ Cu. Efisiensi sambungan pada penelitian ini diperoleh sebesar 69 % terhadap kekuatan tarik base metal aluminum. Nilai konduktivitas listrik meningkat seiring meningkatnya kecepatan putaran tool dari 1000 rpm ke 1200 rpm dan sudut kemiringan tool dari 1 derajat ke 3 derajat. Tegangan sisa yang dihasilkan memiliki tren menurun seiring meningkatnya kecepatan putaran tool dari 1000 rpm ke 1200 rpm dan sudut kemiringan tool dari 1 derajat ke 3 derajat.

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Busbars are an important component in generating power for electric motors to drive electric vehicles. There is a need for Busbars with characteristics of light weight, good electrical conductivity, good thermal conductivity, and low maintenance costs. Therefore, the bimetallic Al-Cu Busbar was manufactured using the friction stir welding (FSW) method. The material used in this research is aluminum alloy 6061 series and pure copper with a thickness of 6 mm. The FSW tool uses high-speed steel material with straight cylindrical pins. The FSW process is carried out by varying the tool rotation speed between 1000 rpm and 1200 rpm and the tool tilt angle of 1 degree and 3 degrees. In the stir zone, an Al-Cu composite-like structure is formed with copper particles in the aluminum matrix. From the Vickers hardness test, the highest hardness value was 220.5 HV in the TMAZ Cu area. The efficiency of the connection in this study was obtained at 69% of the tensile strength of the aluminum base metal. The value of electrical conductivity increases with increasing tool rotation speed from 1000 rpm to 1200 rpm and tool tilt angle from 1 degree to 3 degree. The resulting residual stress have trend decrease as the tool rotation speed increase from 1000 rpm to 1200 rpm and tool tilt angle from 1 degree to 3 degree. "

"Aluminum, as a conductor material, has long been used for high-voltage overhead transmission lines due to its economic value and high electrical conductivity. By adding Al2O3np and alloying elements such as zirconium (Zr), cerium (Ce), and magnesium (Mg), aluminum’s strength and performance could be improved without compromising too much of its electrical conductivity. The focus of this research was to investigate the mechanical, electrical properties, and microstructure of Al-0.12%Zr-0.15%Ce-5%Mg, reinforced with different volume fractions (from 0.5 to 1.5%) of Al2O3 nano particles, using the stir casting method. The tensile strength of the composite was improved by up to 1.2 vf-% in alumina, and decreased with further addition due to clustering and pores, while elongation was reduced with when increasing the reinforcement. It was found that the electrical conductivity of the composite generally decreased with the addition of reinforcement. The microstructure observations showed that the composites yielded finer grains and more pores than the unreinforced alloy, with 1.2vf-% of reinforcement having the finest grain. The electrical conductivity of the composite was 44% IACS, which is still lower than that of the unreinforced alloy."

"Metode resistivitas listrik merupakan salah satu metode eksplorasi sumber daya alam. Metode ini digunakan untuk menyelidiki kondisi materi di bawah permukaan bumi dengan cara mengalirkan arus listrik ke dalam tanah melalui sepasang elektroda listrik kemudian menghitung beda potensial di antara dua elektroda potensial dengan menggunakan voltmeter. Hasil pengukuran beda potensial ini dapat digunakan untuk menaksir konduktivitas di dalam bumi. Pada proses penaksiran ini diperlukan cara menghitung potensial listrik di suatu media. Berkaitan dengan masalah tersebut, maka pada skripsi ini akan dibahas model potensial listrik di suatu media dan mencari solusi dari model tersebut.

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Electrical resistivity method is an exploration method which is used to investigate the nature of the structures below the surface by employing current source. The current is injected on the surface by using the current electrodes and the electrical potential differeneces are measured by using voltmeter at the potential electrodes. The potential difference measurements can be used to estimate the conductivity in the earth. In the estimation process, the calculated electrical potential in a medium is needed. So in this skripsi, a model of the electrical potential in a medium will be discussed and solved."

"The gas diffusion layer (GDL) is one of the critical components of a proton exchange membrane fuel cell (PEMFC). It is generally made of a fossil-fuel-based carbon material. In this study, carbon composite paper (CCP) for GDL was prepared by using carbon material obtained from coconut coir. To obtain the CCP, 80 wt% carbon material from the coconut coir and 20 wt% polymer binder (ethylene vinyl acetate and polyethylene glycol) were mixed in xylene solvent at 100°C, cast on molded glass, and then rolled. The carbon material consists of a mixture of carbon fibers (length: 2 mm) and powders (size: 74 µm). Subsequently, the CCP was treated with polytetrafluoroethylene solution (10 wt%). The physical properties of the CCPs, such as through-plane electrical conductivity, porosity, density, and hydrophobic properties, were investigated. Scanning electron microscopy and energy-dispersive spectroscopy mapping were used to analyze the morphology and polytetrafluoroethylene (PTFE) distribution in the CCP. The through-plane conductivity test showed that CCP with 70 wt% carbon fiber, 10 wt% carbon powder, and 20 wt% polymer was the optimum sample, and it showed the highest electrical conductivity of 2.22 S cm-1. The physical properties of PTFE-treated CCP, such as porosity, density, and contact angle, were almost similar to that of commercial carbon paper used as a GDL. Therefore, the CCP prepared from coconut coir can be applied as a GDL in a PEMFC."

"Polianilin PANi adalah salah satu polimer konduktif yang paling banyak dipelajari. Pada penelitian ini, PANi telah berhasil disintesis melalui reaksi polimerisasi oksidatif kimia yang dilangsungkan pada 3 temperatur larutan berbeda yaitu masing-masing pada 17 0C, 27 0C dan 57 0C. Selama proses polimerisasi anilin berjalan terlihat adanya peningkatan temperatur larutan meskipun tidak signifikan sehingga selama durasi 500 menit reaksi berjalan, temperatur larutan relatif sama. Hasil dari reaksi polimerisasi oxidatif adalah berupa emeraldine base polyaniline atau PANi-EB. Struktur PANi dikonfirmasi dengan FTIR ditandai dengan adanya vibrasi stretching C-N bilangan gelombang 1144 cm-1 dan vibrasi stretching C=C dari benzenoid pada bilangan gelombang 1493 cm-1. Sifat konduktif PANi diperoleh melalui pemberian protonasi menggunakan asam kuat masing-masing HCl dan HClO4. Diperoleh hasil, nilai konduktivitas PANi-EB sebesar 0,92-4,67 x 10-6 S/cm. Nilai konduktivitas ini mengalami peningkatan 102 kali pasca doping menggunakan HCl dan 106 kali pasca doping HClO4. Nilai konduktivitas listrik tertinggi adalah sebesar 4,678 S/cm. Semua PANi hasil sintesis memiliki kemampuan penyerapan gelombang elektromagnetik pada rentang frekuensi 10 GHz-15 GHz. Nilai RL tertinggi sekitar -11 dB pada frekuensi 10,5 GHz dan 12.5 GHz diperoleh dari PANi-EB hasil polimerasi pasca deprotonasi.

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Polyaniline PANi is one of the most studied conductive polymers. In this study, PANi has been successfully synthesized through chemical oxidative polymerization reactions that were carried out at 3 different solution temperatures, respectively at 17 0C, 27 0C and 57 0C. During the aniline polymerization reaction, there was an increase in the temperature of the solution, although not significant, hence, during a duration of 500 minutes reaction time, the solution temperature was relatively un changed. Polymerization reaction has resulted PANi in the form of emeraldine base polyaniline or PANi EB. The formation of PANi was confirmed by FTIR, which characterized by vibration stretching C N at wave number 1144 cm 1 and vibration stretching C C of benzenoid at wave number 1493 cm 1. The conductive property of PANi was obtained through doping by a protonation using strong acids HCl and HClO4. It was found that conductivity value PANi EB was 0.92 4.67 x 10 6 S cm. This conductivity value increased 102 times after doped with HCl and 106 times after doped with HClO4. The highest electrical conductivity value was 4.678 S cm. All synthesized PANi has the ability to absorb electromagnetic waves in the frequency range 10 GHz 15 GHz. The highest RL values of about 11 dB at frequencies 10.5 GHz and 12.5 GHz were obtained from PANi EB."