Articles

GRAPHITE AS A HYDROGEN STORAGE IN FUEL CELL SYSTEM: COMPUTATIONAL MATERIAL STUDY FOR RENEWABLE ENERGY Gunawan, Rahmat; Radiman, Cynthia Linaya; Martoprawiro, Muhamad Abdulkadir; Dipojono, Hermawan K.
Jurnal ILMU DASAR Vol 17 No 2 (2016)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (376.871 KB) | DOI: 10.19184/jid.v17i2.3499

Abstract

The Hydrogen storage based-graphite materials have been investigated theoretically via Density Functional Theory (DFT) approach. The native graphite was compared to the modified graphite, namely the intercalation graphite (GICs, graphite intercalated compounds). Here the GICs was intercalated by alkali metals (Li, Na and K). The electronic structures, energetics and atomic orbital contributions of hydrogen-graphite system, GICs, and hydrogen-GICs were studied by calculation approach of gradient corrected PBE (Perdew-Burke-Ernzerhof) for recovery of exchange-correlation energy. The calculation was supported by using basis set of the plane waves whereas the computation of electron-core by using Ultrasoft Vanderbilt pseudopotential. The computational calculation provides four main studies i.e. molecular geometry relaxation, determination of electronic bands structure of energy, energy state density (DOS) and atomic orbital contribution by charge density differences.Keywords: Density Functional Theory, hydrogen gas, graphite intercalated material
INVESTIGATIONS ON THE MECHANISM OF ARTIFICIAL PHOTOSYNTHESIS OF CA-PC-PDI AND DENDRIMER MOLECULE BY DFT CALCULATIONS Gunawan, Rahmat; Hammamiyah, Ulinnuha; Fadillah, Fahmi; Saleh, Chairul; Sitorus, Saibun
Jurnal ILMU DASAR Vol 19 No 2 (2018)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (636.376 KB) | DOI: 10.19184/jid.v19i2.7142

Abstract

Artificial photosynthesis modelling of Ca-Pc-PDI complex Ca Phthalocyanine Perylenediimide), and dendrimer molecule using Density of Functional Theory (DFT) Method has been studied to showed the energy efficiency of these compounds in terms of electron transfer in photosynthesis. The Analysis of Ca-Pc-PDI and dendrimer compound and also chlorophyl has been done in all computations using the GAMESS-US software. The computations result in this research showed that the large wavelength complex compounds of Ca-Pc-PDI obtained was 138.3299 nm and energy efficiency obtained was 0.89 eV. The data analysis states that the absorption of harvest light energy of complex compounds Ca-Pc-PDI lies in the far UV spectrum. The other side, the polyphenylene dendrimer structure molecular orbital analyses it was found that the dendrimer was capable of electron transfers as indicated by the existence of HOMO and LUMO and result comparisons with chlorophyll. UV wavelengths of the polyethylene dendrimer and chlorophyll, respectively, suggesting that the polyphenylene dendrimer is capable of substituting chlorophyll in artificial photosyntheses. We can states from the result that these compound ability to be applied in the modeling of artificial photosynthesis as a material of energy absorption that mimics the workings of chlorophyll in terms of electron transfer in natural photosynthesis process. Keywords: Artificial photosynthesis modelling, Ca-Phthalocyanine-Perylenediimide complex, and dendrimer molecule
STUDI MOLEKUL KITOSAN SEBAGAI MEMBRAN PENGHANTAR PROTON (H) DENGAN METODE AB INITIO Wibowo, Arif Ari; Gunawan, Rahmat; Sitorus, Saibun
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

Penelitian ini bertujuan untuk mengetahui apakah senyawa kitosan mampu menggantikan kinerja nafion sebagai penghantar proton (H+). Proses pengkajian dan perhitungan dilakukan secara kimia komputasi dengan menggunakan metode ab initio. Hasil analisis menunjukkan nilai energi kitosan sebesar -1384.7601 eH dan energi kitosan setelah membawa proton (H+) mengalami penurunan masing-masing sebesar -1385.2272 eH, -1385.8487 eH, -1386.3393 eH, -1386.9652 eH, -1387.4508 eH. Hal ini membuktikan bahwa kitosan menjadi stabil sehingga mampu digunakan sebagai penghantar proton (H+).
STUDI DOCKING MOLEKULAR SENYAWA KUERSETIN, KALKON DAN TURUNANNYA SEBAGAI INHIBITOR SEL KANKER PAYUDARA MC-7 (MICHIGAN CANCER FOUNDATION-7) Lelita, Resy; Gunawan, Rahmat; Astuti, Winni
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.v17i1.460

Abstract

Molecular Docking studies Quercetin, Chalcone and its derivate inhibitor to breast cancer cells MCF-7 (Michigan Cancer Foundation-7) have been done. The results showed that the docking energies after the process of binding on mode 1 of four compounds Quersetin -7.4 Kcal/mol, 2-(3,4-dihidroksifenil)-5,7-dihidroksi-3-metoksi-3,4-dihidro-2H-1-benzopyran-4-on -6.8 Kcal/mol, Chalcone -6.7 Kcal/mol and 3-(2,4-dihidroksifenil)-1-fenilpropan-1-on -6.6 Kcal/mol. Quercetin formed hydrogen bondings with amino acid  of Aspartic Acid 61, Arginine 65, Arginine 68, Fenilalanin 71 and Serin 75. , 2-(3,4-dihidroksifenil)-5,7-dihidroksi-3-metoksi-3,4-dihidro-2H-1-benzopyran-4-on formed hydrogen bondings with amino acid of Alanin 59, Asparagine 102 dan Arginine 105. Chalcone formed hydrogen bondings with amino acid of Glitamic Acid 94 and 3-(2,4-dihidroksifenil)-1-fenilpropan-1-on formed hydrogen bondings with amino acid of Tyrosine 67. Quercetin is as potential than anticancer drug than chalcone, -(3,4-dihidroksifenil)-5,7-dihidroksi-3-metoksi-3,4-dihidro-2H-1-benzopyran-4-on and 3-(2,4-dihidroksifenil)-1-fenilpropan-1-on.
STUDI KOMPUTASI REAKSI ADSORBSI DISOSIASI GAS O 2 PADA PERMUKAAN Pt-Fe DENGAN METODE TEORI FUNGSI KERAPATAN -, Darmin; Gunawan, Rahmat; Panggabean, Aman Sentosa
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 Muttaqin, Hevin; Saleh, Chairul; Gunawan, Rahmat
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.
STUDI KOMPUTASI REAKSI ADSORBSI DISOSIASI GAS O2 PADA PERMUKAAN Pt-Fe DENGAN METODE TEORI FUNGSI KERAPATAN -, Darmin; Gunawan, Rahmat; Panggabean, Aman Sentosa
JURNAL KIMIA MULAWARMAN Vol 10, No 2 (2013)
Publisher : 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 alfadlil, Boby Royan; Sitorus, Saibun; Gunawan, Rahmat
JURNAL KIMIA MULAWARMAN Vol 11, No 2 (2014)
Publisher : Universitas Mulawarman

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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)μ Kata kunci: Sulfonamida, Antimalaria, Qsar, Regressi, Ab-Initio
ANALISIS AMONIAK TERLARUT PADA TANAMAN LAMUN (Thalassia testudinum) DALAM MEDIA AIR Sundari, Dewi; Alimuddin, Alimuddin; Gunawan, Rahmat
JURNAL KIMIA MULAWARMAN Vol 12 No 2 (2015)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

A research about the analysis of dissolved ammonia in seagraas plants (Thalassia testudinum) at water’s media has been carried out. A research aimed to determined the ammonia concentration in the water’s seagrass plants, and also the effect of ammonia variations concentration at the growth water media after planting for 1, 2, 3 dan 4 weeks, and determined the ability of seagrass to absorb dissolved ammonia. Water as its plant media was placed in to 4 cups that have been added dissolved ammonia as 0, 3, 5 dan 7 mg/L respectively. The concentration of dissolved ammonia from water and seagrass samples were measured by phenate method using a visible spectrophotometer at a wavelength of 650 nm. The result showed that during the planting of four weeks the concentration of dissolved ammonia in the water as its plant media decreased while the concentration of dissolved ammonia in seagrass planst increased. The results of the first week, concentration of dissolved ammonia at growth water’s media, respectively for 9,0234 mg/L; 12,5562 mg/L; 14,5293 mg/L and 16,9269 mg/L. After the fourth week, the concentration of dissolved ammonia decreased as 4,0520 mg/L; 7,3479 mg/L; 8,2848 mg/L and 8,4061 mg/L  
ADSORPSI FENOL OLEH ARANG AKTIF DARI AMPAS KOPI Sunandar, Nisa Hayatun Nufus; Wirawan, Teguh; Gunawan, Rahmat
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 -, Bohari Abdul Kahar Agustin Pratiwi, Agustin Agustinus Pata, Agustinus Albar Alhabib, Albar Alimuddin - Alimuddin Alimuddin Amalia Saleha, Amalia Aman Sentosa Panggabean Andriyaningrum, Suci Anggraini, Nur Linda Anggriani, Merry Ardiansyah - Aspin Aspin, Aspin Boby Royan alfadlil, Boby Royan Bohari Yusuf Chairul Saleh Cynthia L. Radiman Cynthia Linaya Radiman, Cynthia Linaya Darmin -, Darmin Dewi Sundari, Dewi Eko Haryanto Erwin Erwin Eva Marliana, Eva Fadillah, Fahmi Fahrul Fhozi, M Nur Yasin Finqo Aprianto, Finqo Hadi Nur Hammamiyah, Ulinnuha Herman K. Dipojono, Herman K. Hermawan K. Dipojono Hevin Muttaqin, Hevin Hideaki Kasai Jahada, Jahada Julia N, R.R Dirgarini Jumaidil Awal, Jumaidil Kartika Pratiwi Kurniasih, Ririn Feby Lelita, Resy Lelita, Resy Margarita, Margarita Margarita, Margarita Maria Amelia Kristianingrum, Maria Amelia Melanie David, Melanie Muhamad A. Martoprawiro Muhamad Abdulkadir Martoprawiro Muhammad A. Martoprawiro, Muhammad A. Mukhamad Nurhadi, Mukhamad Nasri Nasri, Nasri Nindia, Azrina Nindia, Azrina Nisa Hayatun Nufus Sunandar, Nisa Hayatun Nufus Noor Hindryawati, Noor Nurul Fatimah Palentin, Ersa Rizkita R R Dirgarini J. N Subagyono, R R Dirgarini J. N Ratna Kusumawardani, Ratna Rini, Eka Setia Rudi Kartika, Rudi Saibun Sitorus, Saibun Sari, Prinka Susmita Sarwawan, Ade Putri Hawiyah Sihotang, Recha Defrosa Morasih Samta Sihotang, Recha Defrosa Morasih Samta Slamet Supriyadi Subagyono, R R Dirgarini Julia Nurlianti Sugiarti - Suyitno Suyitno Syafriyanti, Yuly Taufik Rachman Teguh Wirawan, Teguh Utomo, Drajat Bangun Veronika, Tangke Wahdana Kusuma Sari, Wahdana Kusuma Wibowo, Arif Ari Winni Astuti, Winni Wirhanuddin, Wirhanuddin Yulianti Kartika, Yulianti