Karakterisasi Reaktor Plasma Cvd Untuk Deposisi Diamond-like Carbon Coating

Kertas kerja ini melaporkan karakterisasi reaktor plasma CVD yang telah dirancang bangun dengan catu daya DC untuk deposisi film tipis DLC dengan gas metana (CH4) dan argon (Ar) sebagai sumber gas.Hasil eksperimen menunjukkan bahwa tegangan operasi plasma dipengaruhi oleh tekanan reaktor, laju lairan gas, jenis gas, komposisi campuran gas CH4 dan argon, jarak elektroda dan suhu katoda

Sifat Optik Film Tipis Galium Oksida Dengan Doping Eu (5%)

Dalam penelitian ini, telah dikaji sifat optic film tipis Ga2 O3:Eu (5%) yang ditumbuhkan dengan menggunakan reaktor DC unbalanced magnetron sputtering (home made). Dari hasil karakterisasi UV-nir, dapat ditunjukkan bahwa kehadiran doping Eu (5%) telah menurunkan reflektansi film. Kondisi ini sesuai dengan citra SEM, yang menunjukkan bahwa film dengan doping Eu (5%) mempunyai struktur morfologi yang kasar. Dari hasil karakterisasi dengan UV-nir juga diperoleh optical bandgap film Ga2O3 sebesar 3,4 eV dan tidak dipengaruhi oleh kehadiran doping Eu(5%). Kehadiran Eu(5%) pada Ga2O3 telah meningkatkan intensitas fotoluminisensi tetapi tidak berpengaruh secara signifikan pada puncak spektrum fotoluminisens film Ga2O3 (~600 nm). Kata kunci: Ga2 O3 , Ga2O3:Eu(5%), dc magnetron sputtering, fotoluminisens

KARAKTERISASI REAKTOR PLASMA CVD UNTUK DEPOSISI DIAMOND-LIKE CARBON COATING

Kertas kerja ini melaporkan karakterisasi reaktor plasma CVD yang telah dirancang bangun dengan catu daya DC untuk deposisi film tipis DLC dengan gas metana (CH4) dan argon (Ar) sebagai sumber gas.Hasil eksperimen menunjukkan bahwa tegangan operasi plasma dipengaruhi oleh tekanan reaktor, laju lairan gas, jenis gas,  komposisi campuran gas CH4 dan argon, jarak elektroda dan suhu katoda

KARAKTERISASI REAKTOR PLASMA CVD UNTUK DEPOSISI DIAMOND-LIKE CARBON COATING

Kertas kerja ini melaporkan karakterisasi reaktor plasma CVD yang telah dirancang bangun dengan catu daya DC untuk deposisi film tipis DLC dengan gas metana (CH4) dan argon (Ar) sebagai sumber gas.Hasil eksperimen menunjukkan bahwa tegangan operasi plasma dipengaruhi oleh tekanan reaktor, laju lairan gas, jenis gas, komposisi campuran gas CH4 dan argon, jarak elektroda dan suhu katoda

Characterization of Spent Coffee Grounds in the Community as Supporting Materials for Renewable Energy

Coffee grounds are a by-product of the coffee brewing process. Currently, coffee grounds in the community are still untapped waste. Whereas spent coffee grounds has the potential to be converted into various high value bio-products that are environmentally friendly. This study aims to characterize coffee grounds waste which is popular in the community as a supporting material for renewable energy. This study uses a comparative method of 3 samples of Arabica coffee grounds (SCG-A), Robusta (SCG-R), and the Arabica-Robusta blend (SCG-AR) from coffee brands that are popular in Indonesian. Quantitative analysis was carried out by comparing the percentage of residual yield of the three samples. Qualitative characterization of coffee grounds was carried out using the FTIR 8300/8700 Spectrophotometer. The results of the three samples showed different rendemen values, namely 70% SCG-A, 60% SCG-R, and 80% SCG-AR. The FTIR test results showed that the three spent coffee grounds had the same functional group characteristics in the frequency range of 650–3900 cm-1. The detection of the hydroxyl functional group (-OH), the asymmetric strain of the CH bond of the methyl group (-CH3), and the stretching vibration of CO in the COH bond found in coffee grounds waste shows its potential as a supporting material for renewable energy if a further process is carried out in the form of pyrolysis/calcination at room temperature. 700◦C. Utilization of spent coffee grounds in the community can be done by establishing a Spent Coffee Grounds Bank (SCG Bank), educating the public so that they are willing to donate spent coffee grounds, and managing SCG as a supporting material for renewable energy.Ampas kopi merupakan hasil samping yang diperoleh dari proses penyeduhan kopi. Saat ini, ampas kopi yang ada di masyarakat masih menjadi limbah yang belum dimanfaatkan. Padahal limbah ampas kopi berpotensi untuk dikonversi menjadi berbagai bio-produk bernilai tinggi yang ramah lingkungan. Penelitian ini bertujuan untuk mengkarakterisasi limbah ampas kopi yang populer di masyarakat sebagai bahan pendukung energi terbarukan. Penelitian ini menggunakan metode komparasi 3 sampel limbah ampas kopi Arabica (SCG-A), Robusta (SCG-R), dan perpaduan Arabica-Robusta (SCG-AR) dari merk kopi yang populer di masyarakat Indonesia. Analisis kuantitatif dilakukan dengan membandingkan persentase rendemen residu dari ketiga sampel. Karakterisasi limbah ampas kopi secara kualitatif dilakukan menggunakan Spektrofotometer FTIR 8300/8700. Hasil perhitungan rendemen ketiga sampel menunjukkan nilai yang berbeda, yaitu 70% SCG-A, 60% SCG-R, dan 80% SCG-AR. Hasil Uji FTIR menunjukkan ketiga ampas kopi memiliki karakteristik gugus fungsi yang sama pada rentang frekuensi 650–3900 cm-1. Terdeteksinya gugus fungsi hidroksil (-OH), regangan asimetris ikatan C-H gugus metil (-CH3), dan vibrasi ulur C-O dalam ikatan C-O-H yang terdapat pada limbah ampas kopi menunjukkan potensinya sebagai bahan pendukung energi terbarukan apabila dilakukan proses lanjutan berupa pirolisis/kalsinasi pada suhu 700◦C. Pemanfaatan limbah ampas kopi di masyarakat tersebut dapat dilakukan dengan mendirikan Bank Limbah Ampas Kopi (SCG Bank), edukasi kepada masyarakat agar bersedia menyumbangkan limbah ampas kopi, dan pengelolaan limbah ampas kopi menjadi bahan pendukung energi terbarukan

Analysis of the Need for Android Based Mobile Learning Development to Improve Student Science Literations

Science learning in Indonesia has not succeeded in increasing scientific literacy skills, as indicated by the decreasing international ranking from year to year. One of the efforts made to improve scientific literacy is using Android-based learning media. This study aims to analyze the need for the development of instructional media to improve students' scientific literacy at MTs Al Uswah Bergas Semarang Regency. This type of research is a descriptive study that is to describes the current situation. The data instruments used were interviews, observation, and questionnaires. The results of the research on the analysis of the needs for learning media based on android showed that 38% of the 80 students, namely 30 students agreed to develop Android-based learning media, while 29% of the students showed disagreement, 21% strongly agreed, and 12% strongly disagreed. There are aspects of literacy then students including; literacy as mastery of science as knowledge was 63%, 66% as a way of thinking, 62% of scientific literacy as a way of learning, 62% of the aspects of mastery of the competence of the interaction of science, technology, and society. Therefore, it is necessary to conduct research on the development of Android-based mobile learning media to improve students' scientific literac

A Complete Arduino-Based Mathematical Pendulum Experiment Tool with Real-Time Data Acquisition Using an Excel Spreadsheet

It is very important for students to understand the concept of simple harmonic motion, such as a mathematical pendulum. Students need an experiment tool on mathematical pendulums that is capable of providing measurement results of various physical quantities of mathematical pendulums accurately and precisely. This research aims to (1) describe the specifications of an Arduino-based mathematical pendulum experiment tool, (2) describe the results of measurements of acceleration due to gravity, and (3) describe the effect of changes in deviation on the period at small angles. This research used the experiment method. The research results showed that (1) the Arduino-based mathematical pendulum experiment device is equipped with an HC-SR04 ultrasonic sensor to measure the length of the string and an FC-51 infrared sensor to measure the period with a precision of 94.9% and accuracy of 99%, (2) the average result of acceleration due to gravity measurements at various string length was (9.72 ± 0.19) m/s2,and (3) the mathematical pendulum period between angles of 1-13 degrees did not show a significant difference, showing that at small angles, the oscillation period is not affected by deviation