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PENGARUH WAKTU SONIKASI SELAMA SINTESIS TERHADAP KRISTALINITAS MCM-41 BERBASIS SILIKAT Fauzi S, M. Mahfudz; Sutarno, Sutarno; Suyanta, Suyanta
CAKRA KIMIA (Indonesian E-Journal of Applied Chemistry) Vol 5 No 2 (2017)
Publisher : Magister Program of Applied Chemistry, Udayana University, Bali-INDONESIA

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Abstract

ABSTRAK: Telah disintesis MCM-41 dengan metode sonikimia dengan berbahan dasar natrium silikat sebagai sumber silika dan setiltrimetilamonium bromida sebagai surfaktan. Campuran homogen dari semua reagen disonikasi dengan variasi waktu selama 60 menit, 90 menit, 120 menit, dan 150 menit. Padatan yang terbentuk selama sonikasi, disaring dan dikeringkan selama 6 jam pada 110 ºC dan dikalsinasi pada 550 ºC selama 6 jam juga. Hasil karakterisasi dengan menggunakan XRD dan spektroskopi FTIR menunjukkan kondisi optimum MCM-41 diperoleh dengan sonikasi selama 90 menit.     ABSTRACT: MCM-41 was synthesized by using sonichemistry method with sodium silicate as silica source and surfactants cethyltrimethylammonium bromide (CTMABr). The homogeneously mixtures were sonicated for 60 minutes, 90 minutes, 120 minutes, and 150 minutes.  The solid materials during sonication were dried for 6 hous at 110 ºC and calcined at 550ºC for 6 hours too. By using XRD and FTIR, the result showed that the optimum product of MCM-41 was obtained at the time of sonication for 90 minutes.  
PENERAPAN PENDEKATAN PEMBELAJARAN SISTEMIK UNTUK MENINGKATKAN PEMAHAMAN KONSEP MAHASISWA PADA KULIAH KIMIA DASAR I Suyanta, Suyanta; Marfuatun, Marfuatun; LFX, Endang Widjajanti
Jurnal Pendidikan Matematika dan Sains Vol 1, No 1: June 2013
Publisher : Faculty of Mathematics and Natural Sciences, Yogyakarta State University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jpms.v1i1.12478

Abstract

Tujuan penelitian ini adalah mengetahui langkah-langkah penerapan pendekatan pembelajaran sistemik pada kuliah Kimia Dasar I dan mengetahui ada tidaknya peningkatan pemahaman konsep maha-siswa pada Kuliah Kimia Dasar I setelah menggunakan pendekatan pembelajaran sistemik. Penelitian ini di desain sebagai penelitian tindakan kelas yang meliputi empat tahap yaitu perencanaan, tindakan, pengamatan, dan refleksi. Subyek penelitian adalah mahasiswa Pendidikan Kimia yang mengikuti mata kuliah Kimia Dasar I. Obyek penelitian adalah pemahaman konsep mahasiswa. Penerapan pendekatan pembelajaran sistemik dilakukan dengan diskusi dan pemberian tugas. Mahasiswa diminta untuk membu-at diagram siklis yang menunjukkan keterkaitan antar materi kimia. Hasil penelitian menunjukkan ada peningkatan kemampuan berpikir komprehensif mahasiswa, dengan skor kemampuan konsep kimia mahasiswa pada siklus I sebesar 31,48 dan siklus II sebesar 35,48, dengan skor maksimal 50.Kata kunci: pendekatan sistemik, diagram siklis, kemampuan konsep kimia
PREPARATION AND CHARACTERIZATION OF LANTHANUM (III) SELECTIVE ELECTRODE BASED ON 1,10-DIAZA-4,7,13,16-TETRAOXACYCLOOCTADECANE-N,N'-DIACETIC ACID AS AN IONOPHORE Suyanta, Suyanta; I.R, Susanto; Buchari, Buchari; Noviandri, Indra
Jurnal Pendidikan Matematika dan Sains No 1 (2006): Jurnal Pendidikan Matematika dan Sains Tahun XI
Publisher : Faculty of Mathematics and Natural Sciences, Yogyakarta State University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jpms.v11i1.12381

Abstract

The preparation and characterization of lanthanum (III) ion selective electrode based on the 1,10-diaza-4,7,13,16-tetraoxacyclooctadecane-N,N'-diacetic acid as ionophore was studied. The electrode was prepared with an inner solution system in a membrane composition that contained active DACDA ionophore, the anionic side of KTCPB, the plasticizer of NPOE and a PVC matrix support. The good response was obtained with a slope of 19.53 +- 1.62 mV/decade and a good correlation between potential and lanthanum (III) concentration. Electrode could response with a detection limit of 3.92x10^-6 M and range measurement between 10^-5 M to 10^-1M. Electrode is steady at pH 4-9 and the best condition of inner solution concentration at 10^-3 M. Response time was 27.1 seconds and their life time was 50 day.Kata kunci: lanthanum ion-selective-electrode, PVC membrane, 1,10-diaza-4,7,13,16-tetraoxacyclooctadecane-N,N'-diacetic acid
THE EFFECTS OF PROBLEM-BASED LEARNING METHOD ON STUDENTS’ LEARNING INDEPENDENCE OF CHEMISTRY LEARNING IN HIGH SCHOOL Suyanta, Suyanta; Laksono, Endang W.; Fadhilah, Novia Fitri; Rizky, Ihwan
Jurnal Kependidikan: Penelitian Inovasi Pembelajaran Vol 3, No 2: November 2019
Publisher : LPPM UNY

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jk.v3i2.19695

Abstract

Chemistry learning in high school that trains and develops students? self-sufficiency and independence has not been done optimally because learners still depend on getting information and knowledge from teachers. Problem-based learning method used in the teaching and learning process is expected to facilitate students? with self-reliance and learning independence. This method is a problem-oriented learning method that makes students be accustomed to solving problems in order to train their ability in discoveringa concept in the learning process. Teaching learning process with PBL model is done for the subject matter of acid & base solution and electrolyte & non electrolyte solution. Learning independence assessed in this study were self-management, motivation, and confidence. The data of the study were in the form of descriptive quantitative data and analyzed using Anava / Anacova test. The research findings showed that there was a difference of students? learning independence through the application of problem-based learning method and control method in teaching and learning process. 
SYNTHESIS BUSAPOLIURETAN DAR! OIL DISTANCE AS HEAT ISOLATOR Rohaeti, Eli; Suyanta, Suyanta
Jurnal Penelitian Saintek Vol 16, No 1: April 2011
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jps.v16i1.1738

Abstract

Penelitian  ini bertujuan  untuk mensintesis  bus a poliuretan dengan memanfaatkan monomer  berbasis  minyak  jarak. Minyak  jarak direaksikan dengan senyawa isosianat dan dengan penambahan air pada komposisi bervariasi. Karakterisasi poliuretan  meliputi  penentuan  gugus  fungsi, massa jenis, konduktivitas termal, ikatan silang melalui uji penggembungan, dan    pengamatan permukaan menggunakan Scanning Electron Microscopy. Poliuretan berhasil disintesis dari minyak jarak dan TDI dengan  penambahan air dan aditif  (PEG400,  PEG 1000, etilendiamin,  1,4-butanadiol, dan asam oleat) ditunjukkan oleh karakteristik  gugus fungsi   khas.   Poliuretan memiliki ikatan silang ditunjukkan oleh  derajat penggembungan bernilai  positif.    Penambahan air dalam sintesis dapat menurunkan massa jenis busa poliuretan. Penambahan aditif berupa PEG400, PEGIOOO, 1,4-butanadiol, dan asam oleat dalam sintesis poliuretan menyebabkan struktur sel busa yang dihasilkan memiliki permukaan dengan ukuran gelembung lebih besar. Penurunan konduktivitas termal busa poliuretan dengan adanya penambahan air disebabkan oleh penurunan massa jenis busa poliuretan dengan penambahan air dalam sintesis busa. Kata kunci: busa poliuretan, konduktivitas termal, minyakjarak,   poliuretan
LIFE WRITING THERAPY DECREASES DEPRESSION IN LATE ADOLESCENCE Istiqomah, Zulaikah Nur; Erawati, Erna; Suyanta, Suyanta
Jurnal Ners Vol 13, No 2 (2018): October 2018
Publisher : Universitas Airlangga

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jn.v13i2.4686

Abstract

Introduction: Late adolescence (16-18 years old) usually experiences a crucial period in life which makes teenagers vulnerable to mood disorders such as depression. One of the interventions that can decrease depression is writing a memoir, biography, diary, and life writing. Writing can disclose the feeling and help mind care. The objective of this study was to investigate the influence of life writing therapy to decrease depression in late adolescence.Methods: This study used pretest-post-test control group design with 40 people as samples, divided into intervention and control groups. Before and after the treatment, both groups were measured using the scale of the PHQ-9A to see the depression in late adolescence of high school students.Results: Life writing therapy shows differences in mean between intervention group and control group with a p-value of 0.000 (? <0.05).Conclusion: The life writing therapy has an effect in reducing depression in students. It facilitates subjects to evaluate, analyze, and reassess past, current and future events so that subjects can get an understanding, develop a solution and self-motivation, accept the existing situation, learn from what is experienced, focus thoughts on positive things, and assess positive things from an event.
STUDY ON EFFECT OF PH AND METAL CONCENTRATION ON THE SYNTHESIS OF DIMENSIONALLY STABLE ANODE GAPHITE/LA2O3-ZRO2 AND GAPHITE/RUO2-TIO2 Suyanta, Suyanta; Kuncaka, Agus
Indonesian Journal of Chemistry Vol 6, No 2 (2006)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.21747

Abstract

The objective of this research is to study the effect of pH and metal concentration toward the mass of metal oxides coated on gaphite in the synthesis of dimensionally stable anode (DSA) gaphite/La2O3-ZrO2 and gaphite/RuO2-TiO2. The synthesis of those  DSA was done by thermal decomposition technique. The solution containing metal ion to be coated (as its oxides) on the gaphite, followed by heating. Those spraying and heating were repeated up to ten times, so that it was expected that all of gaphite surface was covered by the metal oxides. It was concluded that the mass of metal oxides coated on the gaphite was affected by the pH and concentration of metals in the solutian to be sprayed. Treatment by using solution at pH of 4 and 6 produced  more in mass of metal oxides mixture than  using solution of 1 and 2 on pHs. DSA gaphite/La2O3-ZrO2 produced by treatment using solution of 4 and 6 on pHs contained more in mass of La2O3 than of ZrO2; meanwhile DSA gaphite/RuO2-TiO2 produced in this research (for all of treatment) contained more in mass of RuO2 than of TiO2.
IMOBILISASI TIO2 KE DALAM RESIN PENUKAR KATION DAN APLIKASINYA SEBAGAI FOTOKATALIS DALAM PROSES FOTOREDUKSI ION HG2+ Ridho, Rosyid; Wahyuni, Endang Tri; Suyanta, Suyanta
Jurnal Kimia Valensi Jurnal Valensi Volume 3, No.2, November 2013
Publisher : Lembaga Penelitian dan Pengabdian Kepada Masyarakat Syarif Hidayatullah State Islamic Uni

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (325.133 KB) | DOI: 10.15408/jkv.v3i2.505

Abstract

Abstrak Dalam rangka mengembangkan bahan fotokatalitis TiO2 pada penelitian ini telah dilakukan preparasi fotokatalis TiO2-Resin yang disertai dengan karakterisasi dan uji aktivitas untuk proses fotoreduksi ion Hg(II). Preparasi imobilisasi ini dilakukan dengan metode pertukaran ion yang di ikuti dengan kalsinasi pada suhu tertentu. Pada preparasi telah dipelajari pengaruh konsentrasi Titanium Isopropoksida sebagai sumber ion Ti(IV) terhadap TiO2-Resin yang dikarakterisasi dengan menggunakan Difraksi Sinar X (XRD) dan Thermografimetri (TGA). Pada proses fotoreduksi ion Hg(II) dipelajari pengaruh massa fotokatalis, kadar TiO2 yang terimobilisasi ke dalam resin, konsentrasi Ion Hg(II), dan pengaruh pH. Proses fotoreduksi dilakukan dalam suatu reaktor tertutup yang dilengkapi dengan lampu UV, yaitu dengan cara menyinari campuran yang terdiri dari larutan ion Hg(II) dan serbuk fotokatalis TiO2-Resin, disertai dengan pengadukan selama waktu tertentu. Hasil fotoreduksi dihitung berdasarkan selisih antara konsentrasi ion Hg(II) awal dengan ion Hg(II) yang tak tereduksi. Penentuan konsentrasi ion Hg(II) yang tak tereduksi dilakukan dengan menggunakan Spektrofotometer Serapan Atom (SSA) teknik pembangkitan uap dingin atau Cold Vapor Atomic Absorption Spectrophotometry(CV-AAS). Hasil preparasi menunjukkan semakin tinggi konsentrasi Titanium Isopropoksida yang ditambahkan pada resin semakin tinggi juga kadar TiO2 yang terbentuk pada TiO2-Resin. Hasil uji fotokatalis menunjukkan bahwa penggunaan fotokatalis TiO¬2-Resin dapat meningkatkan hasil fotoreduksi ion Hg(II) yang peningkatannya lebih tinggi dibandingkan TiO2 serbuk. Penambahan fotokatalis dengan massa yang semakin besar menambah efektivitas fotoreduksi terhadap ion Hg(II) yang semakin besar, namun jika ditambahkan massa fotokatalis yang lebih tinggi lagi akan menurunkan efektivitas fotoreduksi terhadap ion Hg(II). Kenaikan konsentrasi Hg(II) menyebabkan efektivitas fotoreduksi semakin rendah. Pada pH 1-4 terjadi kenaikan fotoreduksi pada ion Hg(II), akan tetapi pada pH yang lebih tinggi dari 4 menyebabkan terjadinya penurunan efektivitas fotoreduksi terhadap ion Hg(II).   Kata kunci : Fotokatalis, TiO2-resin, Ion Hg(II)   Abstract To develop TiO2 photoreduction photocatalyst in order to decrease the Hg(II) ion concentrate, in this research, it has been done the TiO2-Resin photocatalyst preparation with the characterization and application to Hg(II) ion photoreduction process. This preparation was done with ion exchange method which followed by studied calcinations at certain temperature. The preparation has been studied the influence of titanium isopropoxide concentrate toward TiO2-Resin which has been characterized by using X-Ray Diffraction(XRD) and Thermografimetry (TGA). In Hg(II) ion photoreduction process, it has been studied the influence of photocatalyst mass, the content of TiO2 which immobilized into sulfonated polystyrene (resin), the ion Hg(II) concentrate, and the pH influence. The photoreduction process has been done in the closed reactor that equipped by UV lamp, and uses the irradiating a mixture which contents of Hg(II) ion solution and TiO2-Resin photocatalyst powder, with the stirring at certain time. The result of photoreduction was calculated based on the difference between the earlier Hg(II) ion concentrate and unreduced Hg(II) ion. The determining of unreduced Hg(II) ion concentrate was done by using cold vapor atomic absorption spectrophotometry (CV-AAS). The preparation result showed that the higher isopropoxide titanium that was added into sulfonated polystyrene, the higher the content of TiO2 that was formed in TiO2-Resin. the result of photocatalyst test showed that the using using of TiO2-Resin photocatalyst can increase the result of Hg(II) ion photoreduction  which the increase is higher than TiO2 powder. The added of photocatalyst by the higher mass, adds the photoreduction effectiveness toward the Hg(II) ion. The higher the Hg(II) concentrate that added, the lower the photoreduction effectiveness. In pH 1-4, there is the photoreduction increase on Hg(II) ion, but in the highest pH that more than 4, it causes the decrease of the photoreduction effectiveness toward the Hg(II) ion.   Keywords : Photocatalyst, TiO2-resin, Hg(II) ion
MECHANISM OF LANTANUM METAL TRANSPORT IN MEMBRAN LIQUID WITH CARRIER SENYA WA MACROSIKLIS Suyanta, Suyanta
Jurnal Penelitian Saintek Vol 8, No 2: Oktober 2003
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jps.v8i2.5560

Abstract

The transport mechanism of lanthanum element in the supported liquidmembrane with macrocycle compound Di benzo IB crowns 6 carriers was studied.  These transport are two kinds. that is  chemical transport and potential   transport.   The  chemical  transport  is   done  with  two  cell compartment   (feed   compartment   and   stripping   compartment).  and separate with membrane that prepare with DiBenzoIBCrown6. Poly Vinyl Chloride. Di  Octyl Ptalate, Sodium  tetra butyl borate  in  Tetra hydro furan solution. A 150 mL solution of La3+   JO-3  Min feed  cell stirrer with300 rpm speed along 3 hour. The stripping phase is solution that varied the pH from  1 to B. The same way. then solution in the feed cell is varied from  10-1  M to 5.10-4  M. The potential  transport is measured with the relative  same  cell.  The potential   transport  measure  with  two  kind reference electrode. Ag/AgCI reference  electrode in the inner cell and calomel reference electrode in the outer cell. Inner cell is contain mixture solution KCL 10-3 M and La3+    IO-3 M and outer cell is contain solution La3"   that variedfrom  10-8 to JO-J  M. The chemical transport is effective at low pH  (below pH  4) and high pH  (upper pH  6). It is good way for separation of La3'.     The transport ion La3+    is low at pH 4 -  6. It is good areafor applied as sensor membrane electrode that has minimal diffusion potential.  The system has good  correlation in potential  membrane that gives slope value 19.36 as Nernst coefficient.
LANTANUM COMPLEXASI STUDY WITH MAKROSIKLIS COMPOUND AND CHARACTERIZATION AS SELECTIVE ELECTRONIC ION LANTANUM Suyanta, Suyanta; Sunarto, Sunarto; Sari, Lis Permana
Jurnal Penelitian Saintek Vol 16, No 2: Oktober 2011
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jps.v16i2.3389

Abstract

The aim of this research are (1) to study the complexation constant of La(III) ion by N,N?-dikarboksimetildiaza-18-crown-6 ligant with difference concentration of KNO3, and (2) to study the lanthanum (III) ion selective electrode (La-ISE) potential response which follows the Nernst equation. The characters of the electrode studied are: response time, life time, detection limit, dynamic range and selectivity. The complexation constant of La(III) ion by N,N?- dikarboksimetildiaza-18-crown-6 ligant are finded by potentiometry titration with 0.0005 M, 0.001 M, dan 0.005 M KNO3 supported electrolite. The titration are doing by 0.00794 M KOH until pH 7. The result of constant complexation (Kf) La(III) ion with N,N?-dikarboksimetildiaza-18-crown-6 difference KNO3 0.005 M, 0.001 M, dan 0.005 M simultaniuesly are 101,02 , 101,12, dan 101,32. The electrode had a response time of 27.14 ± 4.79 seconds and could be used for 50 days. The linear range was between 10-5 M to 10-1 M and the detection limit is 3.92x10-6 M.