Article Per Year (5 Year)
p-Index From 2018 - 2023
10.974
P-Index
This Author published in this journals
All Journal Jurnal Pendidikan dan Pembelajaran Jurnal Matematika & Sains JSEH (Jurnal Sosial Ekonomi dan Humaniora) Jurnal Pamator : Jurnal Ilmiah Universitas Trunojoyo Madura Jurnal Dimensi PURBAWIDYA: Jurnal Penelitian dan Pengembangan Arkeologi Poltekita : Jurnal Ilmu Kesehatan JURNAL PENELITIAN EKONOMI DAN AKUNTANSI (JPENSI) Majalah Ilmiah Warta Dharmawangsa Akrab Juara : Jurnal Ilmu-ilmu Sosial International Journal Of Science, Technology & Management (IJSTM) Jurnal Edutrained : Jurnal Pendidikan dan Pelatihan Lentora Nursing Journal
Ismunandar
Departemen Kimia, FMIPA, Institut Teknologi Bandung
Religion Aerospace Engineering Agriculture, Biological Sciences & Forestry Arts Humanities Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Industrial & Manufacturing Engineering Mathematics Mechanical Engineering Medicine & Pharmacology Nursing Public Health Social Sciences Transportation Other

Published : 104 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 104 Documents
Search

 1   2   3   4   5 
Struktur dan Sifat Piroklor Oksida BixY2-xTi2O7 Ismunandar Ismunandar; Brendan J. Kennedy
Jurnal Matematika & Sains Vol 7, No 2 (2002)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Structure and bonding properties of some quarternary pyrochlore oxides, BixY2-xTi2O7, 0.2 £ x £1.63, have been determined by analysis of powder neutron and synchrotron X-ray diffraction data. These oxides form a series of cubic pyrochlore type of oxides, where the cell size increases with Bi content. The expansion of the cell size is accompanied by decreasing of the electron densities of Bi cations and significant shift of Bi-O charge transfer. The refinements indicated that at high Bi contents, the Bi/Y and O sites are not fully occupied. This results indicates that the smaller Ti2O6 network in titanate pyrochlores can not fully accommodate the large Bi cations. There is no indications of any pyrochlore formation from the reaction of (Bi2O3:2TiO2). Temperature dependent studies on this compositions revealed that neither phase transitions nor pyrochlore phase were observed in the temperature range 25 £ T £1100°C.
Trend Pembentukan Piroklor Ln2Te2O7, Ln = La, Nd, Eu dan Gd Ismunandar Ismunandar; Irawan Haryanto; Santi Dewi
Jurnal Matematika & Sains Vol 8, No 1 (2003)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

As an extension of Weber, F. A. and Schleid, T. work, attempts to prepare Ln2Te2O7, Ln = La, Nd, Sm, Eu and Gd using the solid state reaction have been conducted. The products were characterized using X-ray powder diffraction methods. La2Te2O7 (a = 11,3821 Å) was formed with impurities TeO3, La2O2Te and La2TeO6, while for Nd2Te2O7 (a = 11,1564 Å) the impurities were TeO3, Nd2O2Te and Nd2TeO6. Both were decomposed above 850 °C. Neither Eu nor Gd formed pyrochlore, instead mixtures with dominant phases of Ln2Te2O7.2. It could be supposed that ionic radii of Eu and Gd too small to stabilize pyrochlore structure. Attempts to prepare Bi2Te2O7 and Pb2Te2O7 have not successful yet.
Penentuan Energi Kisi Oksida-Oksida Piroklor Dede Suhendar; Ismunandar Ismunandar
Jurnal Matematika & Sains Vol 11, No 1 (2006)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Lattice energy of pyrochlore oxides prediction is important in relation with the synthesis effort. This work was aimed to find an equation that could be used to predict the lattice enthalpy of pyrochlore oxides. As standards, pyrochlores with known enthalpy formation were used to calculate the lattice entalphy via Born Haber cycle U(BHC). Lattice energies, U, of pyrochlore oxides were calculated by Glasser (G), Glasser-Jenkins, (GJ), and Yoder-Flora, (YF) equations. Plotting of Born-Haber lattice energies U(BHC) vs. U(G), U(GJ), and U(YF) resulted in R2 = 0.9564, 0.8671, and 0.9993, respectively. Based on the fitting of U(BHC) vs. U(YF), then a combination of Yoder-Flora and Kapustinskii equations were formulated and tested for U(BHC) of pyrochlore oxides. The Yoder-Flora-Kapustinskii (YFK) equation was U(YFK)pyrochlore = Σ U(K) oxide of A + Σ U (K) oxide of B where U(K) is lattice energy of oxide calculated by Kapustinskii equation using ionic radii of A in eight coordination number, and B in six coordination number, except for B ions from oxide fluorite structures in eight coordination number. The differences between U(YFK) and U(BHC) were < 3 %..
Synthesis and Magnetic Properties of a Fe-Mn-Cr Multinuclear Complex with 4-Amino-1,2,4-triazole and Oxalate Ligands Iis Siti Jahro; Djulia Onggo; Ismunandar Ismunandar; Susanto Imam Rahayu; Esther Jacoba Martha Vertelman; Petra van Koningsbruggen
Jurnal Matematika & Sains Vol 11, No 3 (2006)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

A multinuclear Fe-Mn-Cr complex with 4-amino-1,2,4-triazole (NH2trz) and oxalate (ox) ligands has been synthesized successfully. The formula of the [Fe(NH2trz)3][ClO4][MnCr(ox)3].4H2O complex has been obtained based on the metal and C, H, N contents. The presence of water molecules, metal-ligand bonding and bridge ligand in the multinuclear complex has been confirmed by its infrared spectrum. The compound crystallizes in the hexagonal system with cell parameters of a = b = 18.695 Å and c = 57.351 Å. The compound shows a gradual spin crossover for iron(II) in the [Fe(NH2trz)3]2+ with transition temperature (T1/2) of 205 K. The antiferromagnetic interaction between Cr(III) and Mn(II) ions in the [MnCr(ox)3]n n- network is observed from the Weiss constant (θ) of -2.3 K.
Sintesis dengan Metode Hidrotermal dan Karakterisasi Senyawa Berstruktur Aurivillius Bi4Ti3O12 [Synthesis of Aurivillius Bi4Ti3012 using Hydrothermal Method and Structured Compound Characterization] Muhammad Rizal; Ismunandar Ismunandar
Jurnal Matematika & Sains Vol 12, No 1 (2007)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The Bi4Ti3O12 powder was synthesized using hydrothermal method from Bi2O3/TiO2 and Bi(OH)3/TiO2 as starting materials and NaOH as mineralizer. Characterization of the obtained powder was carried out using X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR). High purity of Bi4Ti3O12 powder was obtained from reaction at 240 °C, 72 hours and NaOH of 3 M for both starting materials. The obtained diffraction patterns were similar with the standard pattern (PDF, no. 35-0795). The FTIR spectrum revealed two absorption peaks at 587 and 827 cm-1, which are characterictic absorbtion of octahedral TiO6 in Bi4Ti3O12 structure.
Sintesis dan Karakterisasi Senyawa BerstrukturAurivillius Empat dan Lima Lapis dan Penentuan Sifat Feroelektriknya Edi Mikrianto; Ismunandar Ismunandar
Jurnal Matematika & Sains Vol 9, No 3 (2004)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Aurivillius oxides with composition of Na0,5Bi4,5Ti4O15 (NBT), K0,5Bi4,5Ti4O15 (KBT), Sr4Bi2Nb2Ti3O18 (SBNT), Ba4Bi2Nb2Ti3O18 (BBNT)and Bi5Ti5FeO18 (BTF) have been synthesised using the solid state reaction. The obtained oxides were polycrystalline. All the oxides were white, except that Bi5Ti5FeO18 was brick red in colour. Structure type determination was carried out using Phasanx software and PDF data base. It can be concluded that all oxides adopted orthorhombic crystal system and space group A21am with unit cell parameter a = 5.427(2) Å , b = 5.459(3) Å and c = 40.78(2) Å for Na0,5Bi4,5Ti4O15; a = 5.430(1) Å, b = 5.5258(6) Å and c = 50.747(5) Å for K0,5Bi4,5Ti4O15 ; a = 5.5439(9) Å ; b = 5.5258(6) Å and c = 50.747(5) Å for Sr4Bi2Nb2Ti3O18 ; a = 5.540(2) Å, b = 5.579(4) Å and c = 50.962(8) Å for Ba4Bi2Nb2Ti3O18 ; whilst for Bi5Ti5FeO18 a = 5.520(1) Å, b = 5.569(3) Å and c = 50.36(1) Å. Ferroelectric properties measurement showed that polarization remanent Pr(+) and Pr(-) 0.049 μCcm-2 for Na0,5Bi4,5Ti4O15 ; 0.051 μCcm-2 for K0,5Bi4,5Ti4O15; 0.045 μCcm-2 for Sr4Bi2Nb2Ti3O18; 0.050 μCcm-2 for Ba4Bi2Nb2Ti3O18 and 0.050 μCcm-2 for Bi5Ti5FeO18.
Sintesis dan Karakterisasi BaSrAl4O8, BaSrAl3FeO8, dan BaSrAl2Fe2O8 Darwin Ismail; Ismunandar Ismunandar
Jurnal Matematika & Sains Vol 9, No 4 (2004)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

BaSrAl4O8, BaSrAl3FeO8 and BaSrAl2Fe2O8 oxides have been synthesized and their crystal structures type were determined by XRD diffraction. The diffraction patterns were very close to that of BaSrGa4O8, which has space group P63 (No. 173). All of the compounds have AlO4 tetrahedra (as GaO4), form the six-membered rings sharing corners, and the Ba and Sr atoms occupy large cavities of the six-member rings. Fe atoms possibly replace Al atom in the structure. From Proszki analysis in a hexagonal crystal system and P63 space group (No.173), the obtained cell parameters, a and c for BaSrAl4O8, BaSrAl3FeO8 and BaSrAl2Fe2O8 were successively as follows (8.984(2), 8.625(3)) Å; (10.377 (4), 8.619(5)) Å; and (10.454(3), 9.140(3)) Å. Based on ferroelectric properties obtained from RT-66A oscilloscope instrument, only BaSrAl3FeO8 compound exhibited a significant hysteresis loop pattern.
Studi Teoretis Struktur Elektronik dan Sifat Transisi Spin Kompleks [Fe(dpa)2(NCS)2] Yusthinus Thobias Male; Djulia Onggo; Muhamad Abdulkadir Martoprawiro; Ismunandar Ismunandar
Jurnal Matematika & Sains Vol 14, No 3 (2009)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The computational method B3LYP*/6-31G(d) has been used for predicting the mononuclear spin transition (ST) complexes properties, i.e. [Fe(dpa)2(NCS)2] with cis and trans isomers. Computational results showed that in vacuum and methanol, cis-[Fe(dpa)2(NCS)2] isomer gave a reasonable value of ∆Eel for ST. In methanol, the cis isomer was more stabilized because that isomer showing more higher dipole moments (21,59 D) than the trans isomer and unsubstituted complex, [Fe(dpa)3]2+ (5,70 and 0,03 D). This results showed that if those complexes were synthesized, in the ambient temperature they have high spin properties but only cis-[Fe(dpa)2(NCS)2] isomer has ST properties. Analysis of main atomic orbitals populations showed that the electronic ground bands and the next ground bands are assigned to ligand-to-ligand charge-transfer (LLCT) transitions because of the charge transfer from NCS-ligand to the main ligand. It can be concluded that computational method B3LYP*/6-31G(d) gives more predictive power to mononuclear ST complex.
Sintesis Zeolit Mordenit dengan Bantuan Benih Mineral Alam Indonesia Shofarul Wustoni; Rino R. Mukti; Agus Wahyudi; Ismunandar Ismunandar
Jurnal Matematika & Sains Vol 16, No 3 (2011)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Abstract Commercialized Indonesian natural mineral was generally suspected to contain natural zeolite. However, according to X-ray diffraction pattern, there is no indication of zeolite fingerprint. Hence, this research aims to use this mineral as seed in a hydrothermal synthesis to further investigate the possibility of growing zeolite material. Mordenite zeolite was resulted as the product and this concludes that the building blocks of natural zeolite might be present in this local mineral. Keywords: Indonesian mineral, Natural zeolites, Mordenite, Zeolite synthesis, Seed, Hydrothermal. Abstrak Mineral alam Indonesia yang sudah komersial pada umumnya dianggap mengandung zeolit alam. Namun, pola difraksi sinar X nya menunjukkan bahwa tidak ada indikasi puncak-puncak khas zeolit. Oleh karena itu, penelitian ini bertujuan untuk menggunakan mineral alam sebagai benih dalam sintesis hidrotermal sebagai upaya menginvestigasi kemungkinan untuk menumbuhkan material zeolit. Zeolit Mordenit dapat dihasilkan sebagai produk dan hal ini menyimpulkan bahwa mineral lokal ini mengandung unit pembangun zeolit alam. Kata kunci: Mineral alam Indonesia, Zeolit alam, Mordenit, Sintesis zeolit, Benih, Hidrotermal.
Strategi Sintesis Zeolit Hirarkis: Kajian Metode Cetak Lunak dan Cetak Keras Kadja, Grandprix T.M.; Rilyanti, Mita; Mukti, Rino Rahmata; Marsih, I Nyoman; Ismunandar, Ismunandar
Jurnal Matematika dan Sains Vol 18 No 3 (2013)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Zeolit hirarkis saat ini diminati untuk digunakan sebagai katalis yang mampu menyelesaikan masalah pada industri petrokimia dan kimia.  Masalah yang biasa ditemukan pada reaksi katalitik ini menyangkut kepada hambatan difusi molekul, deaktivasi katalis, rendahnya rendemen produk dan selektivitas produk. Hal ini dapat terselesaikan karena zeolit hirarkis memiliki pori tambahan yang berskala meso (>2 nm) selain keberadaan pori mikro (2 nm) despite the presence of micropore (
Co-Authors Agus Syahrani Agus Wahyudi Agus Wartiningsih Agusta, Maulingga Alfrida Semuel Ra'bung aloysius mering Amal, Mukhlisul Ambarita, David Morison Anak Agung Gede Sugianthara Anastasia, Indrayani Anesta, Flora Anggara, Rama Apong, Apong Asfar Muniir, Asfar Asfar Munir Atida, Icha Asih Augustine, Karina Batubara, Herlina Merdekawati Billah, Mu’tashim Brendan J. Kennedy Budiman Budiman Bumadius, Bumadius Canigia, Diego Antoni Cendi, Indah Putri Dalamus, Renny Basajo Darwin Ismail Dede Suhendar Delta, Juliana Dg Mangemba Diecky Indrapraja, Diecky Diecky Kurniawan Indrapraja Dita Amelia, Dita Djau, Nurmala Sari Djulia Onggo Edi Mikrianto eka rahmawati Elpasa, Ega Emelia, Mela Esther Jacoba Martha Vertelman Fahmi Hafid Fatari Fertisari, Imma Firman, Ridho Fitrina, Yola Grandprix T. M. Kadja Gunawan, Arisko Hairusanti, Famela Halim, Idris Henny Sanulita I Nyoman Marsih Iis Siti Jahro Ilham, Gusti Muhamad Imam Azhari, Imam Imanuel, Imanuel Imelda, Brigita Imma Fretisari indah asikin nurani Irawan Haryanto Januarsi, Euis Jelita, Bela Anggun Junaidi Junaidi Junaidi Junaidi Junita, Ellmy Lia Kadja, Grandprix T.M. Kalba, Milda Putri Kamaluddin Kamaluddin Khaeruman Khaeruman, Khaeruman Kharimah, Siti Khasbullah, Angga Kuantani, Irma Maira Kudun, Oktavanus Kurniawan, Ya Laksmi, Nadya Ayu Lestari, Yuyun Ayu Linda, Yusika Lita Maharani Maharani, Maharani Maharani, Novita Anggraini Mawarni, Rizka Rina Meilania, Meilania Meiyana, Ening Juwita Melina, Trivena Metrys Ndama Mita Rilyanti Moh. Mualliful Ilmi, Moh. Mualliful Muhajirin Muhajirin Muhamad Abdulkadir Martoprawiro Mukti, Rino Rahmata Muni ir, Asfar Murni Murni Murti, Elis Syahira Nadya Nurdini Nasrul Nasrul Nasrul Neviaty P Zamani Nopitasari, Maria Nyeti Novianti Novianti Nurarifah Nurarifah Nurul Huda Octaviandri, Octaviandri okiria, Nova Oshin, Oshin Pageans, Christiani Resha Petra van Koningsbruggen Pindi Setiawan Purwati, Kresensia Putri, Indah Risa Putri, Meitika Kaping Rebeka, Modesta Regaria Tindarika Renaldi, Reno Rino R. Mukti Riri, Linovia Rutjuhan, Arta Safitri, Shara Sandi Sandi Santi Dewi Saputra, Pankarius Gagas Sari, Ratih Mulia Shofarul Wustoni Silaban, Chiristianly Silaban, Chiristianly Yeri Silaban, Chiristianly Yery Silaban, Christianly Yeli Silaban, Christianly Yely Silaban, Christianly Yeri Silaban, Christianly Yery Sinta, Emeliana Sumiati Sumiati Supriadi Abdul Malik Susanto Imam Rahayu Taufan E. P, Muhammad Tecla, Susana Timia, Timia Toto, Widina Karma Ulan, Ulan Violeta, Veronica Mega Vizura, Vrinka Widya Ayu Lestari Wilhilmina Tanema, Sesilia Wynni Winda Istiandini Wirawan, Dony Eko Wisthania, Alfiya Nur yarso, Varulian Yery, Christianly Yoan Maria Agusta Yuary Farradia Yulika, Midya Yundari, Yundari Yunisa Is Yuniarti, Tria Yunita, Surina Yusthinus T. Male Zainul, Zainul