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STUDI KOMPUTASI REAKSI ADSORBSI DISOSIASI GAS O 2 PADA PERMUKAAN Pt-Fe DENGAN METODE TEORI FUNGSI KERAPATAN

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

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

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

JURNAL KIMIA MULAWARMAN Vol 11, No 2 (2014)
Publisher : 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)μ Kata kunci: Sulfonamida, Antimalaria, Qsar, Regressi, Ab-Initio

ANALISIS AMONIAK TERLARUT PADA TANAMAN LAMUN (Thalassia testudinum) DALAM MEDIA AIR

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

JURNAL KIMIA MULAWARMAN Vol 9 No 2 (2012)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

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

PENGGUNAAN MONOMER NAFION SEBAGAI PEMBAWA PROTON (H + ) DENGAN METODE TEORI FUNGSI KERAPATAN

JURNAL KIMIA MULAWARMAN Vol 12 No 1 (2014)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Research which has been conducted in this study aims to determine the use of the compound as a Nafion membrane in a Proton Exchange Membrane system (PEM) Fuel Cells which acts as a proton exchange (H + ). After assessment and computational chemistry calculations by calculating the value of energy optimization and molecular orbital energies obtained in the form of the HOMO and LUMO energy. Value calculation is done by using the calculation method of Density Function Theory (density function theory). The analysis showed Nafion energy value of -0.04358 x 10-18 J and Nafion after bringing energy protons (H+) of -0.07629 x 10-18 J. In this case proved that the PEM system of exchanging protons (H + ) is characterized by the presence of increased energy electron activity.Keywords : Proton Exchange Membrane, Fuel Cells, Nafion, Proton (H + ), the activity of electrons, density functional theory, the energy of the HOMO, LUMO energy.

KAJIAN PERUBAHAN UKURAN RONGGA ZEOLIT RHO BERDASARKAN VARIASI RASIO Si/Al DAN VARIASI KATION ALKALI MENGGUNAKAN METODE MEKANIKA MOLEKULER

JURNAL KIMIA MULAWARMAN Vol 14 No 1 (2016)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

The structure modeling of zeolite RHO with variation of Si/Al ratio (5; 4.33; 3.8; 3.36; 3; 2.69; 2.43; 2.2; 2) and variation of alkaline cations (Li+, Na+, K+, Rb+, Cs+, Fr+) calculated by the molecular mechanics method has been investigated. The result shows that the structure of zeolite RHO with Si/Al ratio 3.36 has the most stable structure with a minimum energy 2652.0308 kcal/mol. The most stable structures of zeolite RHO impregnated with cation is that impregnated with Fr+ (alkaline) with a minimum energy 3006.6587 kcal/mol. The result shows that the zeolite RHO structure with cations Fr+ (alkaline) has the largest pore diameter which potentially has the best adsorption capacity.

PEMANFAATAN ABU BATUBARA SEBAGAI ZEOLIT YANG TERDEALUMINASI DALAM MENGADSORPSI FENOL

JURNAL KIMIA MULAWARMAN Vol 12 No 1 (2014)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

A research on the adsorption of phenol with zeolite adsorbent is formed from coal ash by hydrothermal process with the fusion method. In addition, the improvement in the ability of zeolite adsorbtion on the zeolite dealimination process is done. Phenol adsorption process is done through a batch shaker method with test parameters pH, contact time and adsorption capacity factor. The measurement results for the phenol optimum conditions were at pH 10 with a contact time of 30 minutes with the value of the phenol capacity of zeolite was 1,1853 mg/g were obtained using Langmuir isotherm adsorption equation.Keywords : Zeolite of coal ash, dealumination, adsorption, phenol.

STUDI AB INITIO GRAFIT BATUBARA SEBAGAI MATERI PENYIMPAN HIDROGEN

JURNAL KIMIA MULAWARMAN Vol 8 No 1 (2010)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Calculation of density functional theory (DFT) is carried out to investigate the adsorption of six molecules of H2 molecules on a graphite planar layer with a doping of alkali metal (Li, Na, and K). We reported that the DFT-GGA method, the presence of alkali metals on graphite, and H2-(GICs), have changed the interaction and the electronic system. We also reported that the ratio increased electron transfer from K to Na and Li. The calculation of the charge density shows that the increase in energy due to the transfer of electrical charge from GICs to six molecules of H2. This changes the electronic properties of graphite that are important in applications such as hydrogen storage.Keywords: Molecule Hydrogen, Graphite Intercalated Compounds, Density Functional Theory