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All Journal PROSIDING SEMINAR KIMIA Jurnal Kimia Mulawarman JURNAL ATOMIK
Rahmat Gunawan
Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Environmental Science

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STUDI KOMPUTASI REAKSI ADSORBSI DISOSIASI GAS O 2 PADA PERMUKAAN Pt-Fe DENGAN METODE TEORI FUNGSI KERAPATAN Darmin -; Rahmat Gunawan; Aman Sentosa Panggabean
PROSIDING SEMINAR KIMIA SEMINAR NASIONAL KIMIA 2013
Publisher : PROSIDING SEMINAR KIMIA

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Abstract

Platinum purpose as a catalysts on the cathode in a fuel cell hydrogen system gets a role in disconnection of O 2 molecules. Power adsorption and dissociation of O 2 molecules determined the effectiveness and efficiency of the nature of catalyst that is utilized. All thid time metal is considered the most effective as a catalyst in fuel cells hydrogen is Pt. After be done investigation and calculation is known about platinum and iron alloy (Pt-Fe) can be utilized as a catalyst that has approached the effectiveness and efficiency of pure Pt metal. One of the way to determine the effectiveness and efficiency of the catalyst Pt-Fe alloys by calculating the value of the potential energy surface (PES). PES value calculation is done using density functional theory calculations. Analysis’s result point out the value of the potential energy surface (PES) O 2 molecules in the Pt-Fe metal fusion for -929.8341 Ry with optimal distance of 2.4908 A of Pt-Fe’s metal surface and distances among O atoms as big as 3.3211 A.
STUDI DOCKING MOLEKULAR SENYAWA KUERSETIN DAN HESPERITIN SEBAGAI INHIBITOR SEL KANKER DENGAN AUTODOCK VINA Hevin Muttaqin; Chairul Saleh; Rahmat Gunawan
PROSIDING SEMINAR KIMIA SEMINAR NASIONAL KIMIA 2013
Publisher : PROSIDING SEMINAR KIMIA

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Abstract

Kuersetin dan Hesperitin merupakan turunan dari senyawa Flavonoid yang berbeda kelas, Kuersetin kelas Alkohol, sedangkan Hesperetin kelas Alkanon. Docking Molekular, suatu ilmu penelitian secara in silico atau via perangkat lunak (program komputer) dan ditujukan untuk memprediksikan interaksi antara ligan (key) dengan reseptor (lock) dari ikatan hidrogen yang terbentuk. Autodock VINA adalah salah satu program Docking Molekular yang ada, diciptakan oleh Dr. Oleg Trott untuk meningkatkan efisiensi waktu pengerjaan dan akurasi dalam analisa. Dalam penelitian ini masing-masing dari senyawa Kuersetin dan Hesperitin akan di-Docking terhadap dua macam contoh reseptor, sel kanker otak (1S63) dengan ligan aslinya 778 dan sel kanker paru-paru (2ITO) dengan ligan aslinya IRESSA, terlebih dahulu dilakukan optimasi geometri, minimisasi energi juga validasi metode. Penelitian iniditujukan untuk menjelaskan perbandingan Kuersetin, Hesperitin dan ligan-ligan asli sebagai kandidat bahan obat anti kanker. Percobaan Docking, memberikan hasil Kuersetin dan Hesperitin membentuk ikatan hidrogen terhadap asam amino dari masing-masing reseptor. Hal ini menunjukkan bahwa Kuersetin dan Hesperitin memiliki kemampuan sebagai inhibitor, terutama pada sel kanker paru-paru (2ITO), karena potensi keduanya lebih baik dari ligan IRESSA. Walaupun Kuersetin dan Hesperitin tak memiliki potensi lebih baik dari ligan 778 pada sel kanker paru-paru, keduanya masih dapat digunakan sebagai bahan obat alternatif dari anti kanker.
ANALISIS TOTAL SULFUR TERHADAP SAMPEL FEED GAS DENGAN MEMBANDINGKAN STANDAR GAS DAN STANDAR LIQUID MENGGUNAKAN METODE TS-100V Eko Haryanto; Rahmat Gunawan; Chairul Saleh
JURNAL KIMIA MULAWARMAN Vol 12 No 1 (2014)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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The total sulfur analysis in the feed gas sample by using standard gas and liquid has been researched. The concentration of total sulfur obtained from a calibration curve by using standard gas or liquid by TS - 100V. Based on the analysis of measurement linearity, by making curve a linearity from a standard gas H 2 S was 0.999 and standard liquid dibutyl sulfide was 0.998, where both the standard curve can be as a calibration curve because each the value of the correlation coefficient (r) having worth >0.995. Based on the analysis of measurement precision namely repeatability by measuring a feed gas sample train G as many as 5 times been gained. RSD value was 4.17 in standard gas and 4.70 in standard liquid. Both the calibration curve has been accepted because the relative standard deviation values less than 0.67 from Horwitz and still into get allowed range values from 7.3 to 11%. Based on the analysis of accuracy’s measurement is percent recovery for the standard gas was 100.578% and for standard liquid was 104.380%. Both of them has been accepted because it still fit in the allowed range values 80-110%.Keywords : Total Sulfur, H 2 S Standard Gas, Standard Liquid Dibutyl Sulphites and TS-100V
STUDI KOMPUTASI BERBASIS DFT TERHADAP FENOMENA QUANTUM TUNNELING DALAM ISOMERISASI METILHIDROKSIKARBENA Jumaidil Awal; Rahmat Gunawan; Eva Marliana
JURNAL KIMIA MULAWARMAN Vol 9 No 2 (2012)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Density functional theory-based methods have been applied to predict the most possible one among the isomerizations of methylhydroxycarbene considering the probability of hydrogen tunneling occurrence. B3LYP/6-31+G(d,p) and M08-SO/6-31+G(d,p) methods were applied in all computations using GAMESS-US software. There were three steps of computation in this research. First, electronic structure computations of both equilibrium and transition compounds involved in all isomerization alternatives in order to obtain the optimum structures of the compounds. Second, vibrational computations of optimum transition structures to ensure that each of the respective structures is well on its potential energy surface. Third, tunneling analysis accomplished by intrinsic reaction coordinate (IRC) computatuins for all isomerization alternatives followed by tunneling probabilitycalculation using the Wentzel-Kramers-Brillouin (WKB) formula for methylhydroxycarbene isomerizations. The result of this research showed that the DFT methods successfully produced the optimum structure of each compound. Both DFT methods also successfully mapped all the intrinsic reaction coordinates. B3LYP/6-31+G(d,p) method gave tunneling probabilities of 3.55 x 10-19 for the isomerization into acetaldehyde and 3.30 x 10-20 for that into vinyl alcohol. While M08-SO/6-31+G(d,p) method gave tunneling probabilities of 2.38 x 10-23 for the isomerization into acetaldehyde and 4.79 x 10-23 for that into vinyl alcohol.Keywords: DFT, methylhydroxycarbene, hydrogen tunneling, isomerization
DISTRIBUSI LOGAM TIMBAL (Pb) PADA TANAMAN WEDELIA (Wedelia trilobata (L.) Hitch) AKIBAT EMISI KENDARAAN BERMOTOR DI BEBERAPA JALAN KOTA SAMARINDA Amalia Saleha; Alimuddin -; Rahmat Gunawan
JURNAL KIMIA MULAWARMAN Vol 10 No 2 (2013)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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The research has done of "The distribution of lead (Pb) on wedelia plants contaminated by vehicular emission on several main road in samarinda”. This study aimed to determine the metal concentrations of lead in roots, flowers and leaves of plants wedelia at several locations in the city of Samarinda on PM Noor Street, Wahid Hasyim Street, Pahlawan Street, AW Syahrani Street, and Belatuk Street (control location) were the different traffic density and the treatment of leaching on levels of lead found in wedelia plants. The concentrations of lead metal on wedelia plants were measured using an Atomic Absorption Spectrophotometer (AAS) at a wavelength of 283.3 nm. The results showed that The highest levels of Pb obtained on PM Noor and lowest on Belatuk, were the traffic density is high concentration of lead is absorbed more than low traffic density. And the treatment of non-leaching and leaching concentrations obtained difference was not significant, indicating leaching did not significantly affect the concentration of Pb on plants.
PENURUNAN KADAR ION LOGAM KROMIUM PADA LIMBAH INDUSTRI SARUNG SAMARINDA DENGAN MENGGUNAKAN METODE ELEKTROKOAGULASI Yulianti Kartika; Aman Sentosa Panggabean; Rahmat Gunawan
JURNAL KIMIA MULAWARMAN Vol 13 No 1 (2015)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

The reduction of chromium concentration in Samarinda sarong wastewater by electrocoagulation method has been carried out. The research used Atomic Absorption Spectrophotometer (AAS) as an instrument determination level. To determination the optimum levels of each parameters by large percent qualified of electrocoagulation process with used variation of series parameters such as time contact, variation voltage and the distance of electrode. The result of research showed that degradation and is big of elimination percent of metal of Cr have an in with the effect of time contact, voltage and also distance of electrode at optimum hence in getting result of final concentration successively 31,250; 21,325 and 17,925 ppm of concentration early 50,650 ppm. Big of elimination percent of exclusion at optimum parameter in getting result successively 38,302; 57,897 and 64,610 %. Resulted in this research obtained optimum time contact is 30 minutes, optimum voltage is 4,5 volt and optimum distance of electrode is 1 cm.Keywords: Chromium, Samarinda sarong wastewater, Electrocoagulation, Metal electrode
Studi Molekul Kitosan Sebagai Membran Penghantar Proton (H) Dengan Metode Ab Initio Arif Ari Wibowo; Rahmat Gunawan; Saibun Sitorus
JURNAL KIMIA MULAWARMAN Vol 17 No 1 (2019)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/jkm.v17i1.462

Abstract

The aim of this research to know chitosan compound able to replace nafion performance as a conductor of proton (H+). The assessment process and computational chemistry calculations done using ab initio methods. The analysis showed chitosan energy is -1384.7601 eH and chitosan energy after bringing proton (H +) decreased respectively by -1385.2275 eH, -1385.8487 eH, -1386.3393 eH, -1386.9652 eH, -1387.4508 eH. The result obtained proved of chitosan becomes stable so that it can be used as a proton conductor.
STUDI KOMPUTASI REAKSI ADSORBSI DISOSIASI GAS O2 PADA PERMUKAAN Pt-Fe DENGAN METODE TEORI FUNGSI KERAPATAN Darmin -; Rahmat Gunawan; Aman Sentosa Panggabean
JURNAL KIMIA MULAWARMAN Vol 10 No 2 (2013)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Platinum purpose as a catalysts on the cathode in a fuel cell hydrogen system gets a role in disconnection of O2 molecules. Power adsorption and dissociation of O2 molecules determined the effectiveness and efficiency of the nature of catalyst that is utilized. All this time metal is considered the most effective as a catalyst in fuel cells hydrogen is Pt. After be done investigation and calculation is known about platinum and iron alloy (Pt-Fe) can be utilized as a catalyst that has approached the effectiveness and efficiency of pure Pt metal. One of the way to determine the effectiveness and efficiency of the catalyst Pt-Fe alloys by calculating the value of the potential energy surface (PES). PES value calculation is done using density functional theory calculations. Analysis’s result point out the value of the potential energy surface (PES) O2 molecules in the Pt-Fe metal fusion for -929.8341 Ry with optimal distance of 2.4908 A of Pt-Fe’s metal surface and distances among O atoms as big as 3.3211 A.Keywords: Fuel cell hydrogen, Adsorption dissociation O2, PES, Density functional theory (DFT)
STUDI KUANTUM FARMAKOLOGI SENYAWA TURUNAN SULFONAMIDA 2,4 DIAMINO 6 QUINAZOLINE SEBAGAI ANTIMALARIA DENGAN MENGGUNAKAN METODE AB INITIO Boby Royan alfadlil; Saibun Sitorus; Rahmat Gunawan
JURNAL KIMIA MULAWARMAN Vol 11 No 2 (2014)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Telah diterapkan metode berbasis Ab-Initio dalam suatu analisa QSAR (Quantum Structure Activity Relationship) untuk dapat membuktikan dimana letak pusat aktif senyawa sulfonamida yang telah diketahui nilai persen aktivitasnya secara eksperimen laboratorium. Terdapat tiga tahapan komputasi dalam penelitian ini. Pertama, komputasi struktur elektron semua senyawa yang terlibat dalam 16 substiuen senyawa beserta nilai R dari masing-masing senyawa dalamrangka memperoleh struktur optimum serta nila momen dwikutub dan muatan bersih senyawa-senyawa tersebut. Kedua, teknik analisa data dengan pembuatan model kuantum farmakologi dari kombinasi variabel atom-atom yang selalu terdapat pada 16 senyawa tersebut. Ketiga, analisa regresi multilinear dengan menggunakan beberapa parameter statistik seperti koefisien korelasi (r dan r 2 ) dan standar estimasi (SE). Hasil penelitian ini menunjukkan bahwa metode Ab-Initio berhasil membuktikan daerah pusat aktif senyawa sulfonamida dengan n= 16, R= 0,99, dan nilai SE= 0,08 menunjukkan hubungan kuantitatif yang nyata terhadap antiplasmodial dengan model persamaan terbaik sebagai berikut : log A = 13,10(±0,04)qC1 – 193,21qC2 + 95,47C3 – 63,18qC4 – 2,54qC5 +151,38qC6 + 9,33(±0,02)qC7 + 30,32(±0,02)qC8 – 2,91qO1 – 0,04(±0,66)qO2 +72,37(±0,03)qN1 – 108,91(±0,03)qN1 + 2,96qS + 1,01(±0,04)? Kata kunci: Sulfonamida, Antimalaria, Qsar, Regressi, Ab-Initio
ADSORPSI FENOL OLEH ARANG AKTIF DARI AMPAS KOPI Nisa Hayatun Nufus Sunandar; Teguh Wirawan; Rahmat Gunawan
JURNAL KIMIA MULAWARMAN Vol 9 No 2 (2012)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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The comparison of phenol adsorption with activated carbon from coffee residue has been conducted. The first step in this study is coffee residue activation with ZnCl2 in 85oC during 7 hours. The coffee residue was dryed in 24 hours at 110oC and after that it was dissolved by activated carbon with 10% HCl and pH neutralized by using aquades 65oC. The activated carbon was determinate at pH 2-6, with time 15-60 minutes and phenol concentration 2-10 mg/L. From that result would be processed with isotherm Freundlich’s equation. The optimum conditions result obtained at pH 4, time 30 minutes and adsorption capacity of 1.733 mg/g. The activated carbon has been used into waste samples which have addition of phenol and obtained result 2.4751 mg/L from 6.4778 mg/L for waste water A. W. Sjahranie hospital and 0.0560 mg/L from 2.0068 mg/L for Karang Mumus River.Keywords: Phenol, adsorption, activated carbon, coffee residue
Co-Authors Agustinus Pata Alimuddin - Amalia Saleha Aman Sentosa Panggabean Ardiansyah - Arif Ari Wibowo Boby Royan alfadlil Bohari Yusuf Chairul Saleh Cynthia L. Radiman Darmin - Eka Setia Rini Eko Haryanto Eva Marliana, Eva Finqo Aprianto Herman K. Dipojono Hevin Muttaqin Hideaki Kasai Jumaidil Awal Melanie David Muhammad A. Martoprawiro Nisa Hayatun Nufus Sunandar Resy pakasi Rudi Kartika, Rudi Saibun Sitorus Sugiarti - Teguh Wirawan Yulianti Kartika