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(MOLECULAR MODELING BASED ON AB INITIO METHOD FOR ANTI CORROSION COMPOUND PHENYL-PHYRAZOLINDOLE DERIVATIVES) Hamdiani, Saprini; Hadisaputra, Saprizal
Jurnal Lembaga Penelitian Universitas Mataram Vol 18, No 2 (2014): Jurnal Penelitian
Publisher : Jurnal Lembaga Penelitian Universitas Mataram

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Abstract

A molecular modeling has been carried out on the phenyl-phyrazolindole derivatives as anti-corrosion by ab initio methods at the HF/DZV level of theory. Quantum-chemical parameters for anti-corrosion compounds such as orbital energies (EHOMO and ELUMO), ionization potential (I), electron affinity (A) and electronegativity (χ) has a linear relationship with the anti-corrosion efficiency (IE%). The substituent changes on the anti-corrosion compound causes the enhancement of anti-corrosion eficiency. The 1NH2-PI compound has the highest anti-corrosion efficiency of 83.12%. This value is better than the phenyl- phyrazolindole (PI) which has anti-corrosion efficiency of 79.30%. This theoretical study will have a major contribution in helping the design and synthesis of novel anti-corrosion compound that has a higher efficiency
Mixed Langmuir-Blodgett Films of Cu-3,5-bistetrabutyl phenylporphyrin, arachidate acid and hexatriacontane in ordinary environment: A UV Visible Study Hadisaputra, Saprizal
Jurnal PIJAR Vol 4, No 1 (2009)
Publisher : Jurnal PIJAR

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                                                ABSTRACTThe study of mixed Langmuir-Blodgett Films multilayer was conducted in ordinary experiment conditions by using metallo-porphyrin derivative (3,5-bistetrabutyl-phenylporphyrin with Cu as central metal) and arachidate acid with and without trigger molecule, hexatriacontane. We demonstrated that the mixed multilayer which consist of 4, 20 and 40 layers for each mixed solution (molar ratio porphyrin : arachidic acid : hexatriancontane, 1,5 : 10 : r, where r is 0, 0.5) successfully transfers into glass plates as Langmuir-Blodgett Films and characterized the transferred films using UV visible spectroscopy. The area per monolayer porphyrin molecule is approximately 15-21 Å2. The first mixed solution (porhyrin: arachidic acid) produced good multilayer while the second mixed solution (porphyrin : arachidic acid : trigger molecule, hexatriancontane) did not produce 20 and 40 layers as it was expected. Some possible problems such as cleanliness, isotherms condition and compression speed of forming multilayer will be discussed. Key words: Langmuir-Blodgett Films, multilayer, Cu-3,5-bistetrabutyl phenylporphyrin, UV  visible spectroscopy.ABSTRAK Telah dilakukan studi terhadap multilapis film Langmuir-Blodgett pada kondisi eksperimen sehari-hari menggunakan campuran Cu-3,5-bistetra-butil fenilporpirin, asam arakidat dengan dan atau tanpa inisiator, heksatriakantone. Campuran multilapis film (perbandingan molar porpirin : asam arachidic : heksatriakantone, 1,5 : 10, r, dimana r = 0, 0,5)  terdiri dari 4, 20 dan 40 lapis berhasil di transfer ke atas kaca preparat sebagai Langmuir-Blodgett film dan dilakukan karakterisasi dengan spektroskopi sinar tampak (UV-visible spectroscopy). Luas daerah per molekul porpirin adalah15-21 Å2. Campuran pertama (porpirin : asam arakidat) memberikan multilapis yang baik, sedangkan campuran dengan adanya inisiator tidak menghasilkan 20 dan 40 lapisan seperti prediksi. Beberapa kemungkinan penyebab hasil tidak optimum seperti tingkat kebersihan (cleanliness), kondisi isotermal dan kecepatan kompresi saat pembentukan multilapis film akan di bahas Kata-kata kunci: Langmuir-Blodgett Films, multilapis, Cu-3,5-bistetrabutyl-phenylporphyrin, spektroskopi sinar tampak.
KAJIAN PELAKSANAAN PRAKTIKUM KIMIA DI SEKOLAH MENENGAH ATAS NEGERI SE KABUPATEN LOMBOK TENGAH Junaidi, Eka; Hadisaputra, Saprizal; Al Idrus, Syarifa Wahidah
Jurnal Ilmiah Profesi pendidikan Vol 2, No 1 (2017)
Publisher : Fakultas Keguruan dan Ilmu Pendidikan, Universitas Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (199.172 KB) | DOI: 10.29303/jipp.v2i1.41

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Penelitian ini bertujuan untuk melakukan pemetaan terhadap aktivitas praktikum kimia di Sekolah Menengah Atas Negeri se-Kabupaten Lombok Tengah. Penelitian ini merupakan penelitian menggunakan survey dengan metode fishbone diagram (diagram tulang ikan). Pengumpulan data pada survey dijaring menggunakan angket/kuisioner dan wawancara. Jenis kuisioner pada penelitian ini adalah kuisioer tertutup dengan rating scale. Yang menjadi sampel dalam penelitian ini adalah seluruh guru kimia di SMA Negeri Se Kabupaten Lombok Tengah yang terdiri dari 18 sekolah. Data hasil penelitian survei dianalisis menggunakan teknik deskriptif kuantitatif berupa persentase sederhana, dan penggunaan tabel. Untuk interpretasi data permasalahan dan kebutuhan menggunakan kriteria 5 kriteria (sangat baik, baik, cukup, kurang, dan sangat kurang). Sedangkan data yang bersifat kualitatif dianalisis melalui tiga alur yaitu: reduksi data, penyajian data, dan penarikan simpulan atau verifikasi. Berdasarkan hasil analisis data menggunakan bantuan SPSS diketahui bahwa di SMAN se Kabupaten Lombok Tengah; 1) Keadaan Sarana dan Prasarana Laboratorium berkategori Baik dengan nilai rata-rata sebesar 71,09%. 2) Keterlaksanaan Kegiatan praktikum dan relevansinya dengan materi ajar berkategori Baik dengan nilai rata-rata 74,81% 3) Tingkat motivasi guru kimia dalam melaksanakan kegiatan praktikum diketahui sekolah dengan kategori Motivasi Tinggi 2 sekolah (11,1 %), Motivasi Sedang 14 sekolah (77,78%) dan Motivasi Rendah 2 sekolah (11,1%). 4) Korelasi antara keadaan Sarana dan Prasarana Laboratorium dengan Pelaksanaan Kegiatan Praktikum cukup tinggi dengan nilai koefisien korelasi pearson = 0,621. Sedangkan antara Pelaksanaan Kegiatan Praktikum dengan Motivasi guru untuk melaksanakan praktikum memiliki korelasi rendah dengan nilai koefisien korelasi pearson = 0,229. Dengan demikian dapat diketahui bahwa keadaan sarana dan prasarana Laboratorium di SMAN se Kabupaten Lombok Tengah tergolong Baik, Pelaksanaan Kegiatan Praktikum Juga tergolong Baik, akan tetapi ketika dikorelasikan keadaan sarana prasarana dan pelaksanaan kegiatan praktikum terhadap motivasi guru dalam melaksanakan kegiatan praktikum memiliki hubungan korelasi yang rendah.
HYPERCHEM 6.0:PENDEKATAN KOMPUTASI KIMIA UNTUK IDENTIFIKASI ISOMER SENYAWA TURUNAN BENZOFURAN Hadisaputra, Saprizal
Jurnal PIJAR Vol 1, No 2 (2006)
Publisher : Jurnal PIJAR

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Abstract

Telah dilakukan identifikasi isomer struktur senyawa turunan benzofuran, 3-fenil-4. metilbenzofuran dan 3-fenil-6-metilbenzofuran menggunakan program aplikasi Kimia Hyperchem 6.0 berdasarkan hasil kromatoram Gas Kromatografi-Spektrometri Massa (GCMS). Kromatogram hasil di ambil pada kondisi kolom nonpolar CP Sil 5CP. Langkah identifikasi isomer ini adalah menggambarkan struktur isomer pada Hyperchem, melakukan Optimasi Geometri parameter Semi-empirik AM I dengan limit konfergensi = 0,01, menghitung momen dwikutub berdasarkan QSPR (Qualitative Structure and Property Relationship) dilanjutkan dengan identifikasi isomer. Dari perhitungan Hyperchem diperoleh momen dwikutub senyawa 3-fenil-6. metilbenzofuran adalah 0,666 Debye dan senyawa 3-fenil-4-metilbenzofuran adalah 0,882 Debye. Hasil perhitungan momen dwikutub ini mengidentifikasikan bahwa puncak pertama pada kromatogram adalah senyawa 3-fenil-4-metilbenzofuran dan puncak kedua adalah 3-fenil-6-metilbenzofuran.
EFFECT ANALYSIS OF THE DIFFERENT CHANNEL LENGTH AND DEPTH OF PHOTOVOLTAIC THERMAL SYSTEM WITH ∇-GROOVE COLLECTOR Hadisaputra, Saprizal; Zohri, Muhammad; Bahtiar, Bahtiar; Fudholi, Ahmad
International Journal of Electrical and Computer Engineering (IJECE) Vol 10, No 2: April 2020 (PART I)
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (605.537 KB) | DOI: 10.11591/ijece.v10i2.pp1200-1207

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The converted Solar energy as electrical and thermal energy was named photovoltaic thermal (PVT). The aim of this study is to the analysis of different length and depth channel effect of photovoltaic thermal with ?-groove collector by a mathematical model. The matrix inversion was used to analyze the energy balance equation. Simulation results were conducted below the solar intensity of 800 W/m2 and mass flow rate between 0.0069 kg/s and 0.0491 kg/s. Electrical and thermal efficiency was done to assess the effect of different length and channel depth of PVT system with ?-groove collector. The effect of different length and depth of ?-groove collector for electrical and thermal performance is caused by changed mass flow rate. The effect Increasing of the mass flow rate of collector increased the thermal and electrical performance of the ?-groove collector.
PENGEMBANGAN BAHAN AJAR KIMIA BERBASIS PROBLEM BASED LEARNING UNTUK MENINGKATKAN KETERAMPILAN METAKOGNISI Ramdoniati, Nishfiya; Muntari, Muntari; Hadisaputra, Saprizal
Jurnal Penelitian Pendidikan IPA Vol 5, No 1 (2019): January
Publisher : Universitas Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v5i1.148

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This study aims to development of chemical learning material based PBL to improve metacognition skills of students on the material of electrolyte and nonelectrolyte solutions. The type of research used is Research and Development (R & D) with the modification of 4D model into 3D which consists of define, design and develop. The results showed that the average score of the feasibility of learning materials of 3.18 with medium category, The average score of teacher response and the response of learners is 3.58 with the practical category. The effectiveness data of learning materilas based PBL was obtained from N-Gain metacognition skill score of 0.51 in the medium category, meaning that chemical learning materials based PBL is effective to improve metacognition skills on the topic of electrolyte and nonelectrolyte solutions. Keyword: Chemical learning material, problem based learning, metacognitive skills.
THEORETICAL STUDY ON CORROSION INHIBITION PROPERTIES OF 2-ISOPROPYL-5-METHYLPHENOL Hadisaputra, Saprizal; Hamdiani, Saprini; Junaidi, Eka
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 2 (2015): Alchemy Jurnal Penelitian Kimia
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.2.710.102-110

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Corrosion inhibitors of 2-isopropyl-5-methylphenol and its derivatives has been elucidated by means of density functional theory at B3LYP/6-31G(d) level of theory. Effect of electron donating and withdrawing groups such as NH2, SH, CHCH2, CH3, OH, CHO, COOH, F and NO2 on the corrosion inhibitor of 2-isopropyl-5-methylphenol derivatives also have been studied. The quantum chemical parameters such as the frontier orbital energies (EHOMO), ionization potential (I), electron affinity (A) and electronegativity (χ) are closely related to the corrosion inhibition efficiency (IE %) of 2-isopropyl-5-methylphenol derivatives. The presence of electron donating groups increase IE % values meanwhile electron with drawing groups reduce IE % values. The enhancement of IE % follows NO2 < CHO < COOH < SH < F < CH3 < CHCH2 < OH < NH2. Electron donating NH2 group gives 96.38 % of IE %, pure 2-isopropyl-5-methylphenol IE % = 82.70 %. In contrast, electron withdrawing NO2 group gives IE % only 68.66 %. This theoretical study would have a significantly contribution for accelerating corrosion inhibitor experimental to gain optimum results.
PREDICTION OF THE CORROSION INHIBITION EFFICIENCY OF IMIDAZOLE DERIVATIVES: A QUANTUM CHEMICAL STUDY Hadisaputra, Saprizal; Iskandar, Zohrul; Asnawati, Dina
Acta Chimica Asiana Vol 2 No 1 (2019)
Publisher : HKI Nusa Tenggara

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/aca.v2i1.15

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This study aims to determine the the efficiency of corrosion inhibition of imidazole derivatives in carbon steel based on quantum chemical parameters. Density functional theory method was applied in this study. Corrosion inhibition efficiency values ??are strongly influenced by substituent groups. Corrosion inhibition efficiency values ??have a linear correlation with quantum chemical parameters. The amine substituent increased the value of corrosion inhibition efficiency, in contrast nitro group reduced the efficiency of corrosion inhibition. The predicted corrosion inhibition efficiency data of imidazole does agree with the experimental data.  
Theoretical Study on the Extraction of Alkaline Earth Salts by 18-Crown-6: Roles of Counterions, Solvent Types and Extraction Temperatures Hadisaputra, Saprizal; Canaval, Lorenz R; Pranowo, Harno Dwi; Armunanto, Ria
Indonesian Journal of Chemistry Vol 14, No 2 (2014)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (576.723 KB) | DOI: 10.22146/ijc.21259

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The roles of counterions, solvent types and extraction temperatures on the selectivity of 18-crown-6 (L) toward alkaline earth salts MX2 (M = Ca, Sr, Ba; X = Cl-, NO3-) have been studied by density functional method at B3LYP level of theory in gas and solvent phase. In gas phase, the chloride anion Cl- is the preference counterion than nitrate anion NO3-. This result is confirmed by the interaction energies, the second order interaction energies, charge transfers, energy difference between HOMO-LUMO and electrostatic potential maps. The presence of solvent reversed the gas phase trend. It is found that NO3- is the preference counterion in solvent phase. The calculated free energies demonstrate that the solvent types strongly change the strength of the complex formation. The free energies are exothermic in polar solvent while for the non polar solvent the free energies are endothermic. As the temperature changes the free energies also vary where the higher the temperatures the lower the free energy values. The calculated free energies are correlated well with the experimental stability constants. This theoretical study would have a strong contribution in planning the experimental conditions in terms of the preference counterions, solvent types and optimum extraction temperatures.
EXTRACTION OF STRONTIUM(II) BY CROWN ETHER: INSIGHTS FROM DENSITY FUNCTIONAL CALCULATION Hadisaputra, Saprizal; Pranowo, Harno Dwi; Armunanto, Ria
Indonesian Journal of Chemistry Vol 12, No 3 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (740.602 KB) | DOI: 10.22146/ijc.21332

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The structures, energetic and thermodynamic parameters of crown ethers with different cavity size, electron donating/withdrawing substituent groups and donor atoms have been determined with density functional method at B3LYP level of theory in gas and solvent phase. Small core quasi-relativistic effective core potentials was used together with the accompanying SDD basis set for Sr2+ and DZP basis set was used for crown ether atoms. Natural bond orbital (NBO) analysis was evaluated to characterize the distribution of electrons on the complexes. The interaction energy is well correlated with the values of Strontium charge after complexation, the second order interaction energies (E2) and HOMO-LUMO energy gab (∆Egab). The interaction energy and thermodynamics parameters in gas phase are reduced in solvent phase as the solvent molecules weaken the metal-crown ether interaction. The thermodynamic parameters indicated that less feasibility to extract Sr2+ ion directly from pure water without presence of organic solvent. The theoretical values of extraction energy for Sr(NO3)2 salt from aqueous solution in different organic solvent is validated by the experimental trend. This study would have strong contribution in planning the experiments to the design of specific host ligand and screening of solvent for extraction of metal ion.