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PENGARUH KOMPETENSI GURU MATA PELAJARAN TIK TERHADAP MOTIVASI DAN HASIL BELAJAR SISWA Sutarno, Mr Heri; Rohendi, Mr Dedi; Putri, Gigin Gantini
Jurnal Pengajaran Matematika dan Ilmu Pengetahuan Alam Vol 16, No 2 (2011): Jurnal Pengajaran MIPA
Publisher : Faculty of Mathematics and Science Education, Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18269/jpmipa.v16i2.268

Abstract

Penelitian ini dimaksudkan untuk mengetahui sejauh mana kompetensi guru TIK berpengaruh terhadap motivasi dan hasil belajar siswa dalam mata pelajaran TIK. Penelitian ini dilakukan di sebuah sekolah sampel, dengan responden siswa SMA. Penelitian ini menggunakan metode deskriptif kuantitatif dengan metode survey eksplanatory. Analisis data dalam penelitian ini dilakukan dengan 3 (tiga) cara, yaitu: Nilai Skala (Nilai Interval), untuk mengetahui kondisi dari masing-masing variabel; Analisis varians (ANOVA) satu jalur; dan Korelasi untuk mengetahui keterhubungan variabel. Dari penelitian ini diperoleh hasil bahwa kompetensi pedagogik guru TIK yang ada di sekolah sampel tergolong cukup (56,07%), kompetensi kepribadian tergolong cukup (53,72%), kompetensi sosial tergolong cukup (45,22%) dan kompetensi profesional tergolong tinggi (61,20%). Keterhubungan antara kompetensi guru dengan motivasi belajar diperkuat dengan kurangnya tingkat signifikansi sehingga dapat disimpulkan bahwa ada keterhubungan antara keempat kompetensi guru tersebut terhadap motivasi siswa untuk belajar mata pelajaran TIK. Secara parsial hanya kompetensi kepribadian (53,72%) dan kompetensi profesional (61,20%) yang terbukti dapat mempengaruhi motivasi belajar siswa. Untuk hasil belajar, dari hasil penelitian yang dilakukan ternyata keterhubungan antara kompetensi guru dan motivasi belajar terhadap hasil belajar sangat kecil (50%). Sebagai saran dari penelitian ini yaitu instansi pencetak guru harus memastikan agar mahasiswa yang dididiknya memiliki kemampuan kompetensi guru seperti tertulis dalam PP No. 74 tahun 2008 sehingga dapat meningkatkan motivasi dan hasil belajar siswa, yang pada akhirnya keberadaan guru benar-benar bermakna dalam sebuah pembelajaran.Kata Kunci: guru TIK, kompetensi guru, motivasi, hasil belajar
The Effects of Grain Size, Oxidizers and Catalysts on Band Gap Energy of Gelam-Wood Carbon Syarif, Nirwan; Rohendi, Dedi; Haryati, Sri; Dewi, Claudia
http://dx.doi.org/10.31427/IJSTT.2019.2.2.5
Publisher : Unijourn Publisher

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Abstract

The research of the effects of grain size, oxidizers, and catalysts on band gap energy of gelam-wood carbon has been conducted in which the carbons were produced from gelam-wood pyrolysis in high temperatures. The instrumentations used in this study were UV-Vis, FTIR spectrophotometer, and SEM. SEM and FTIR were used to characterize the morphology and the functionality of the carbon surface. UV-Vis spectrograms showed that the electronic property of carbon such as band gap was affected when grain size and surface area were changed. The increase of the functional groups in carbon occurred as the surface area of the carbon was increased. Band gap energy of crystalline carbon became much lower along with the increase in grain size due to the effects of bands-broadening. FTIR spectrograms showed that the carbon contained of hydroxyl and carboxylic groups. The hydroxyls were derived from steam-oxidized carbon that was provided narrower in the interlayer distance and lower-set band gap energy. Carboxylic groups were derived from acid nitric oxidation causing flat layer to become curved. The layers were wider and the band energy was higher. The main factor that affects the electronic structure of metal oxide in carbon/metal oxide composites was atomic alignments. The band gap energy increased along with the increase of the asymmetry alignments in metal oxide.
Electrochemical Evaluation of Lithium-Ion Battery with Anode of Layer-Reduced Biocarbon and Cathode of LiFePO4 Syarif, Nirwan; Rohendi, Dedi; Sya'baniah, Nyimas
http://dx.doi.org/10.31427/IJSTT.2019.2.2.4
Publisher : Unijourn Publisher

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Abstract

The application of reduced carbon anode layer and LiFePO4 cathode was conducted in laboratory-scale battery. Both electrodes were fabricated into lithium - ion battery with LiCl electrolyte in both gel and liquid based. The carbon was prepared by using Hummer method and solvent sonification to exfoliate the carbon layer from biocarbon. The battery performance tests were carried out in potentiostat for Cyclic Voltammetry (CV) and galvanostatic measurements. The highest current of CV measurement can be obtained in the battery with reduced carbon layer anode and 20% of liquid electrolyte. It was calculated that the same battery produced the highest energy and power. Current - Voltage profile is relatively stable in CV of batteries with 40% electrolytes in both gel and liquid media. All batteries have two peaks in both anodic and cathodic. The reduction peaks show in around 0.5 and 1.5 volts. The cathodics show in around –0.5 and –1.5 volts. The best power and energy values are given by battery with rCNSO anode and 20% liquid electrolyte. Galvanostatic profiles show that the 40% electrolytes in the batteries produces a slower discharging process. It was revealed that applying anode of layer reduced biocarbon as the battery electrode caused the discharging to run faster. The highest slope value of the galvanostatic curve can be found in the battery with the electrode of oxidized starting material and 40% of gel electrolyte, while the lowest can be found in 20% gel electrolyte with the same electrode.
Module Stabilizing of Biocarbon Based Electrochemical Capacitor Syarif, Nirwan; Rohendi, Dedi; Sudarsono, Wulandari; Wong, Wai
http://dx.doi.org/10.31427/IJSTT.2019.2.1.5
Publisher : Unijourn Publisher

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Abstract

One of the disadvantages of the electrochemical capacitor (EC) or supercapacitor compared with batteries is its low specific energy. It limits of EC to meet the energy needs of the electrical-electronic devices, such as electric cars. To overcome those limitations, it needs a serial circuit to increase the voltage range, and parallel circuits to increase the storage capacity. Practically, the module that built from 2-6 pieces of 2.5V EC cells will not feasible to make the module with the voltage of 5-15 V. It was found that the voltage of the EC cell could decreases to about 2.0 V, so that the capacitance of the module significantly reduced. This paper reports the basic methods that can be applied to overcome these problems by using a stabilizing or balancing component. The balancing components used in this study were a resistor, a Zener diode, and a Schottky diode. Each component was attached to every EC cell. The influence of the Zener and Schottky diode was observed as a component of a blocking diode. The results showed that the use of a 100-ohm resistor and Zener diode reduces voltage peaks while the use of blocking diode modules leads to increased discharge time. In general, there was no significant change in the charging time, both with and without the balancing and blocking component.
A Review on Production of Hydrogen from Renewable Sources and Applications for Fuel Cell Vehicles Rohendi, Dedi; Rahmah, Dea; Yulianti, Dwi; Amelia, Icha; Sya'baniah, Nyimas; Syarif, Nirwan; Rachmat, Addy
http://dx.doi.org/10.31427/IJSTT.2018.1.2.5
Publisher : Unijourn Publisher

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Abstract

Hydrogen gas is an energy carrier that has many advantages, including energy density for high mass and environmentally friendly. Hydrogen can be produced from various sources by numerous methods. Hydrogen production from renewable sources is interesting, due to the sustainable and inexpensive supply of the raw materials. Among the sources of renewable raw materials for hydrogen production are water and biomass with various production methods. It consists of the electrolysis of water with acidic and basic conditions, as well as thermochemical and biochemical biomass conversion.
Pembuatan Elektroda Fuel Cell dengan Metode Elektrodeposisi Menggunakan Katalis Pt-Cr/C dan Pt/C dan Karakterisasinya Dedi Rohendi; Yulinar Adnan
Jurnal Penelitian Sains Vol 13, No 2 (2010)
Publisher : Faculty of Mathtmatics and Natural Sciences

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (605.744 KB) | DOI: 10.56064/jps.v13i2.148

Abstract

Telah dilakukan penelitian Pembuatan Elektroda Fuel Cell dengan Metode Elektrodeposisi Menggunakan Katalis Pt-Cr/C dan Pt/C yang dilanjutkan dengan karakterisasi konduktivitas dan massa terdeposisi. Penelitian diawali dengan membuat backing layer dari substrat karbon dengan pengikat teflon emulsion dengan perbandingan karbon dan teflon emulsion 1 : 1, kemudian dikarakterisasi konduktivitasnya. Elektroda Fuel Cell dibuat dengan melakukan elektrodeposisi larutan platina (H2PtCl6.6H2O) dan larutan krom (CrCl6.6H2O) pada backing layer dengan konsentrasi bervariasi pada beda potensial 7,5 Volt dan waktu 10 menit. Hasil pengamatan konduktivitas backing layer menunjukkan bahwa backing layer yang dibuat sudah memenuhi syarat sebagai backing layer fuel cell dengan konduktivitas rata-rata sebesar 1,8133.10−1 mhos untuk permukaan dan 2,397.10−2 mhos untuk konduktivitas penampangnya. Hasil elektrodeposisi Pt dan Cr pada backing layer untuk membuat elektroda Pt-Cr/C dan Pt pada backing layer untuk membuat elektroda Pt/C menunjukkan konduktivitas elektrik permukaan mengalami kenaikan, sementara konduktivitas penampangnya tidak mengalami kenaikan secara signifikan. Hasil elektrodeposisi juga menunjukkan bahwa massa katalis Pt dan Cr terdeposisi paling banyak dalam elektroda Pt-Cr/C diperoleh pada komposisi massa Pt : Cr = 40 : 60 dan massa katalis Pt terdeposisi paling banyak dalam elektroda Pt/C diperoleh pada massa Pt = 0,6 mg/cm2.
Thermal Activated of Indonesian Bentonite as A Low-Cost Adsorbent for Procion Red Removal from Aqueous Solution Tarmizi Taher; Dedi Rohendi; Risfidian Mohadi; Aldes Lesbani
The Journal of Pure and Applied Chemistry Research Vol 7, No 2 (2018): Edition May-August 2018
Publisher : Chemistry Department, The University of Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1540.398 KB) | DOI: 10.21776/ub.jpacr.2018.007.02.351

Abstract

Abundant and inexpensive Indonesian natural bentonite was activated by thermal activation at 500 oC for removal of procion red dye as one of the most used synthetic dye in the traditional songket fabric production around Palembang city. Activated bentonite product was characterized by FT-IR, XRD, and thermal analysis. The adsorption process was conducted in batch adsorption system by applying various adsorption parameter condition including, initial pH condition, contact time, and initial dye concentration. The activated bentonite characterization indicates that during the activation process, the structure of the original bentonite was not changed significantly and the result of the thermal analysis revealed that thermal activation at 500 oC was draining the water content without destructing the silica-alumina framework of bentonite. The adsorption kinetics study shows that the procion red adsorption into the activated bentonite follows the pseudo-second order kinetic model. The isotherm adsorption study revealed that procion red adsorption into activated bentonite adapted the Langmuir adsorption isotherm.
Preparation And Characterization Of Cr/Activated Carbon Catalyst From Palm Empty Fruit Bunch Zainal Fanani; Dedi Rohendi; Tri Kurnia Dewi; Muhammad Dzulfikar A
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 1, No 2 (2016): June 2016
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v1.i2.35

Abstract

Preparation and characterization of Cr/activated carbon catalyst from palm empty fruit bunch had been done. The research were to determine the effect of carbonization temperature towards adsorption of ammonia, iodine number, metilen blue number, and porosity of activated carbon and Cr/activated carbon catalyst. The determination of porosity include surface area, micropore volume and total pore volume. The results showed the best carbonization temperature activated carbon and Cr/activated carbon catalyst at 700°C. The adsorption ammonia of activated carbon and Cr/activated carbon catalyst as 6.379 mmol/g and 8.1624 mmol/g. The iodine number of activated carbon and Cr/activated carbon catalyst as 1520.16 mg/g and 1535.67 mg/g. The metilen blue number of activated carbon and Cr/activated carbon catalyst as 281.71 mg/g and 319.18 mg/g. The surface area of activated carbon and Cr/activated carbon catalyst as 1527.80 m2/g and 1652.58 m2/g. The micropore volume of activated carbon and Cr/activated carbon catalyst as 0.7460 cm3/g and 0.8670 cm3/g. The total pore volume of activated carbon and Cr/activated carbon catalyst as 0.8243 cm3/g and 0.8970 cm3/g.Keywords : activated carbon, palm empty fruit bunch, porosity, catalyst, chromium
Analyses of Non-bonding Length, Partial Atomics Charge and Electrostatic Energy from Molecular Dynamics Simulation of Phospholipase A2 – Substrate Nirwan Syarif; Dedi Rohendi
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 1, No 3 (2016): October 2016
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v1.i3.72

Abstract

Abstract: This paper reports molecular dynamics simulation of phospholipase A2 (PLA2)– substrate that has been done. Non-bonding length, partial atomic charge and electrostatic energy were used to evaluation the interaction between PLA2 and substrate. The research was subjected for three types of PLA2 of different sources, i.e, homo sapien, bovinus and porcinus, by using computer files of their molecular structures. The files with code 3elo, 1bp2, dan 1y6o were downloaded from protein data bank.  Substrate structure can be found in 1y60 and was separated from its enzyme structure and docked into two other PLA2 structures for simulation purpose. Molecular dynamics simulations were done for 30000 steps with constant in number of molecules, volume and temperature (NVT). The results showed the existing of flip-flop mechanism as basic feature of PLA2 – substrate reactions. Interaction length analysis results indicated the presence of water molecules on the structures of 1bp2 and 3elo at the time of the simulation was completed. The existence of aspagine at the reaction site confirmed the theory that this amino acid is responsible for the survival of the reaction. the electrostatic energy increased substantially in the interaction after homo sapien PLA2 (3elo) and Bovinus (1bp2) with the substrate. Inverse effect took place in the PLA porcinus (1y6o).Keywords: flip flop, inflammation, in-silico, simulation Abstrak (Indonesian): Telah dilakukan penelitian tentang simulasi dinamika molekuler pada Situs Reaksi Phospholipase A2 (PLA2) dengan substratnya. Analisis panjang non-ikatan, muatan atom parsial dan energi elektrostatis digunakan untuk menilai interaksi antara PLA2 dan substratnya. Penelitian dilakukan pada tiga jenis sumber PLA2, yaitu homo sapien, bovinus dan porcinus dengan menggunakan file komputer untuk struktur molekul dengan kode 3elo, 1bp2, dan 1y6o. Pada file 1y60 terdapat struktur substrat yang dapat ditemukan secara alamiah. Kedua file lainnya tidak mengandung struktur molekul substrat. Simulasi dinamika molekul dilakukan untuk 30.000 langkah dengan konstan dalam jumlah molekul, volume dan suhu (NVT). Hasil penelitian menunjukkan keberadaan mekanisme flip-flop sebagai fitur dasar reaksi PLA2 - substrat. Hasil analisis panjang interaksi menunjukkan bahwa kehadiran molekul air pada struktur 1bp2 dan 3elo pada saat simulasi dilakukan. Keberadaan aspagine di lokasi reaksi menegaskan teori bahwa asam amino ini bertanggung jawab untuk kelangsungan hidup reaksi. energi elektrostatik meningkat secara substansial dalam interaksi setelah homo sapien PLA2 (3elo) dan Bovinus (1bp2) dengan substrat. efek terbalik terjadi di porcinus PLA (1y6o).Kata kunci: flip flop, inflamasi, peradangan, in-silico, simulasi
Oxidation Of Cyclohexane To Cyclohexanol And Cyclohexanone Using H4[α-SiW12O40]/Zr As Catalyst Aldes Lesbani; Menik Setyowati; Risfidian Mohadi; Dedi Rohendi
Molekul Vol 11, No 1 (2016)
Publisher : Universitas Jenderal Soedirman

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (639.036 KB) | DOI: 10.20884/1.jm.2016.11.1.194

Abstract

Synthesis and preparation of polyoxometalate H4[α-SiW12O40].nH2O with Zr as support at various weights of Zr 0.01g; 0.05 g; 0.25 g; 0.5 g; 0.75 g; 1 g and 1.25 g to form H4[α- SiW12O40]/Zr was conducted. The compounds from preparation were characterized using FTIR spectroscopy and crystallinity analysis using X-Ray diffraction. Thus H4[α- SiW12O40]/Zr was applied as catalyst for oxidation of cyclohexane to cyclohexanol and cyclohexanone. Oxidation process was studied through reaction time, hydrogen peroxide amount, temperature, and weight of catalyst. FTIR spectrum of H4[α-SiW12O40]/Zr was appeared at wavenumber 771.53-979.84 cm-1 and Zr at 486.06-1481.33 cm-1. Diffraction pattern of H4[α-SiW12O40]/Zr showed that high crystallinity was identified at 2θ 8o-10o and 28.3o. Based on FTIR spectrum and XRD powder pattern, the optimum preparation of H4[α-SiW12O40]/Zr was obtained using 0.5 g of Zr. The catalytic study of cyclohexane using H4[α-SiW12O40]/Zr at 0.5 g of Zr resulted conversion about 99.73%. Catalyst can convert cyclohexane with the highest conversion then used for further deep catalytic investigation. Optimization of oxidation process resulted optimum reaction time at 2 h, 3 mL of hydrogen peroxide amount, 80 oC of temperature, and 0.038 g of catalyst. The GCMS analysis indicated the oxidation of cyclohexane using H4[α-SiW12O40]/Zr at 0.5 g of Zr formed cyclohexanol and cyclohexanone with selectivity 18.77 and 23.57, respectively.
Co-Authors ACHEAMPONG, KENNEDY Addy Rachmat Ade Gafar Abdullah, Ade Gafar Ade Gaffar Abdullah, Ade Gaffar Adelia, Ory Adhiyanti, Nurmalina Aip Saripudin Aldes Lesbani Amelia, Icha Ana Arrumaisha, Nissa Asep Yudi Permana Assaidah, Assaidah Barlin Barlin Bijak Riyandi Ahadito Budhi Setiawan Budi Mulyanti Dedy Suryadi Dewi, Claudia Edy Herianto Majlan, Edy Herianto Eka Daryanto, Eka Fakhili Gulo Fatma Fatmawati Fatmawati Fauzan, Mochamad Patra Bani Fauzan, Mochamad Rizal Felicity, Felicity Gigin Gantini Putri Hanapi, Zaliza Hanissa Okitasari Hanissa Okitasari Hary Widjajanti Heri Sutarno Hikmawan, Rizki Iskandar, Naufal Nadhif Rabbani Iwa Kuntadi Jefri Jefri Kamin Suamrdi Kamin Sumardi Kamin Sumardi Koehler, Thomas Larutama, Wiku Menik Setyowati Mokhamad Syaom Barliana Muhammad Adli Rizqulloh Muhammad Dzulfikar A Muhammad Faizal Muhammad Oka Ramadhan Muhammad Said MUHAMMAD SAID Muktiarni Mustika Nuramalia Handayani Nirwan Syarif Nirwan Syarif, Nirwan Normah Normah, Normah Nugraha, Agri Triya Oduro-Okyireh, George Oduro-Okyireh, Theodore Permana, Muhammad Aditya Poedji Loekitowati Hariani Pramudita, Resa Purnawan Purnawan Rahmah, Dea Ramadhan, Muhammad Oka Rasim, R Ria Komala Risfidian Mohadi Roer Eka Pawinanto, Roer Eka Salni Septiadi, Jaka Shandyka, Muhammad Fajar Siregar, Batu Mahadi Sri Haryati Steven Julianto Situmeang Subarna, Bambang Sudarsono, Wulandari Sya'baniah, Nyimas Sya'baniah, Nyimas Syabaniah, Nyimas Febrika Syarif, Nirwan Syarif, Nirwan Syarif, Nirwan Syarif, Nirwan Sya’baniah, Nyimas Febrika Tarmizi Taher Tri Kurnia Dewi Wong, Wai Yulianti, Dwi Yulianti, Dwi Hawa Yulinar Adnan Zainal Fanani