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Synthesis of Chitosan-Coated Magnetic Microparticle Using Glutaraldehyde as Crosslinker and PEG as Spacer Arm and Its Application as Adsorbent of Peat Humic Acid Santoso, Uripto Trisno; Rodiansono, R.; Junaidi, Ahmad Budi; Umaningrum, Dewi
Journal of Wetlands Environmental Management Vol 3, No 1 (2015): January-June, 2015
Publisher : Center for Journal Management and Publication

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/jwem.v3i1.5

Abstract

A simple procedure for synthesis of chitosan-coated magnetic microparticle (CMMP) using glutaraldehydeas a cross-linker and polyethylene glycol (PEG) as a spacer arm has been developed. The functionalizedmicroparticle were prepared using an inexpensive, simple, rapid, one-pot process, based on the heating ofchitosan, PEG, and ferrous sulfate mixture at high pH. X-ray diffraction results indicated that the surfacemodifiedFe3O4 microparticle did not lead to phase change unlike the pure Fe3O4. Magnetic chitosanadsorbent has been evaluated for removal of peat humic acid from its aqueous solution.
Synthesis of Chitosan-Coated Magnetic Microparticle Using Glutaraldehyde as Crosslinker and PEG as Spacer Arm and Its Application as Adsorbent of Peat Humic Acid Santoso, Uripto Trisno; Rodiansono, Rodiansono; Junaidi, Budi; Umaningrum, Dewi
Journal of Wetlands Environmental Management Vol 3, No 1 (2015): April, 2015
Publisher : Research Institution, Lambung Mangkurat University

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

Abstract

A simple procedure for synthesis of chitosan-coated magnetic microparticles (CMMP) using glutaraldehyde as a cross-linker and polyethylene glycol (PEG) as a spacer arm has been developed. The functionalized microparticles were prepared using an inexpensive, simple, rapid, one-pot process, based on the heating of chitosan, PEG, and ferrous sulfate mixture at high pH. X-ray diffraction results indicated that the surface-modified Fe3O4 microparticles did not lead to phase change unlike the pure Fe3O4. Magnetic chitosan adsorbent has been evaluated for removal of peat humic acid from its aqueous solution.
IMMOBILIZATION OF HUMIC ACID ON CHITOSAN USING PROTECTED CROSS-LINKING REACTION METHOD AND ITS APPLICATION AS SORBENT FOR Pb(II), Cd(II), AND Cr(III) Uripto Trisno Santoso; Dewi Umaningrum; Utami Irawati; Radna Nurmasari
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (253.04 KB) | DOI: 10.22146/ijc.21620

Abstract

Immobilization of humic acid (HA) on chitosan has been done by using a protected cross-linking reaction method and the product was then utilized as sorbent for Pb(II), Cd(II), and Cr(III). HA was cross-linked with chitosan by using glutaraldehyde in order to obtain sorbent insoluble in aqueous acidic and basic solution. Protection of the active sites of HA was carried out by interacting HA with Pb(II) before performing the cross-lingking reaction in order to maintain its adsorption capacity The result showed that the amount of immobilized HA on chitosan was 99.7% by weight. The solubility of the immobilized HA were < 0.5% at pH 6 and < 1.0% at pH 12. The amount of immobilized HA and its solubility indicated that the protection pretreatment did not interfere the cross-linking reaction between HA and chitosan. The adsorption capacity of the sorbent for Pb(II), Cd(II), and Cr(III) were 416.7 mg/g, 332.3 mg/g, dan 714.3 mg/g, respectively.
Pemahaman konsep IPA siswa SMP melalui pembelajaran problem solving pada topik perubahan benda-benda di sekitar kita Sadiqin, Ikhwan Khairu; Santoso, Uripto Trisno; Sholahuddin, Arif
Jurnal Inovasi Pendidikan IPA Vol 3, No 1: April 2017
Publisher : Program Pascasarjana, Universitas Negeri Yogyakarta (UNY)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (524.478 KB) | DOI: 10.21831/jipi.v3i1.12554

Abstract

Telah dilakukan penelitian untuk mendeskripsikan pemahaman konsep IPA siswa SMP melalui pembelajaran problem solving. Teknik pemilihan sampel dilakukan secara purposive sampling. Subyek penelitian ini adalah siswa kelas VII berjumlah 66 orang. Data penelitian diperoleh menggunakan instrumen tes. Teknik analisis data dengan cara melihat perkembangan n-gain. Hasil penelitian diperoleh rata-rata pemahaman konsep siswa sebelum pembelajaran adalah 52,28 tergolong kategori kurang baik. Skor setelah pembelajaran adalah 77,40 tergolong kategori baik. Model problem solving sesuai untuk pembelajarain sains sekolah menengah pertama dan dapat mendorong siswa untuk membangun pemahaman konsep. Terjadi konstruksi pemahaman konsep siswa melalui proses menghubungkan pengetahuan dalam menyelesaikan masalah pembelajaran.Kata kunci: problem solving, pemahaman konsep, pengetahuan deklaratif, pengetahuan prosedural, perubahan benda-benda di sekitar kita. Junior High School Students? Understanding of the Science Concept Through Problem Solving Learning on the Topic of Change Things Around our Life  AbstractResearch was conducted to describe the results of student learning through problem solving model. Sampling was done by purposive sampling. Subjects are 66 students of class VII. Data were obtained using paper based test. Data analysis techniques by observing the development of n-gain. This study showed that student understanding of pretest is 52,28 point categorized as low and posttest is 77,40 point categorized as good. It mean that the problem solving model suitable to the junior high school science class and encourage students to constantly build understanding of the concept. Construction of the concept through the process of connecting knowledge in solving learning problems.Keywords: problem solving, conceptual understanding, declarative knowledge, procedural knowledge, changes things around us.
IMMOBILIZATION OF HUMIC ACID ONTO CHITOSAN USING TOSYLATION METHOD WITH 1,4-BUTANEDIOL AS A SPACER ARM Uripto Trisno Santoso; Radna Nurmasari; Dewi Umaningrum; Sri Juari Santosa; Bambang Rusdiarso; Dwi Siswanta
Indonesian Journal of Chemistry Vol 12, No 1 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (420.224 KB) | DOI: 10.22146/ijc.21369

Abstract

Immobilization of humic acid (HA) onto chitosan using tosylation method with 1,4-butanediol as a spacer arm has been evaluated. Chitosan was phthaloylated selectively using phthalic anhydride in dimethylformamide as solvent with addition of 5% water (v/v) as cosolvent prior to be tosylated. N-phthaloyl-chitosan and HA were tosylated using tosyl chloride in excess and triethylamine as catalyst at temperature < 10 °C for 12 h. The 6-O-tosyl-N-phthaloyl-chitosan was reacted with 1,4-butanediol in order to obtain a spacer arm attached chitosan. The 6-O-butanol-N-phthaloyl-chitosan was activated by reacting with tosyl chloride. For evaluation on immobilization of HA on chitosan with and without spacer arm, 6-O-tosylbutane-N-phthaloyl-chitosan was reacted with HA and the 6-O-tosyl-N-phthaloyl-chitosan was reacted with HA. The HA immobilized onto chitosan was characterized by XRD and FTIR spectrophotometric method. The result showed that HA can be immobilized covalently onto chitosan after attaching 1,4-butanediol as spacer arm onto 6-O-tosyl-N-phthaloyl-chitosan and activating the product with tosyl chloride, but HA cannot be reacted directly onto 6-O-tosyl-N-phthaloyl-chitosan.
Pengaruh Penyaringan dan Pengeringan Terhadap Ukuran Partikel Oksida Besi: Tinjauan Karakterisasi Kualitatif Menggunakan Mikroskop Optik Uripto Trisno Santoso; Rodiansono Rodiansono; Ahmad Budi Junaidi; Citra Ariyanti; Radhina Oktari; Puput Nopitasari; Hasanah Hasanah
Jurnal Fisika FLUX Vol 1, No 1 (2019): Jurnal Fisika Flux Edisi Khusus Januari 2019
Publisher : Lambung Mangkurat University Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/flux.v1i1.6144

Abstract

Karakterisasi ukuran partikel menjadi salah satu parameter yang sangat penting dalam uji keberhasilan sintesis mikro- maupun nanomaterial. Walaupun secara teori sudah diketahui bahwa beberapa perlakuan fisika seperti proses penyaringan dan pengeringan dapat berpengaruh terhadap ukuran partikel sampel, tetapi perlakuan ini sering diabaikan sehubungan dengan beberapa teknik karakterisasi, misalnya SEM (scanning electron microscopy) mempersyaratkan sampelnya berbentuk serbuk kering.Penelitian ini bertujuanuntukmendapatkan data imiahtentang pengaruh penyaringan dan pengeringan terhadap ukuran partikel oksida besidengan karakterisasi secara kualitatif menggunakan mikroskop optik. Hasil penelitian menunjukkan bahwa proses penyaringan dan pengeringan dapat mempengaruhi ukuran partikel.
POTENSI ASAP CAIR PADA PRODUKSI ARANG KAYU MODEL DESA RANGGANG TANAH LAUT Ahmad Budi Budi Junaidi; Abdullah Abdullah; Uripto Trisno Santoso
Konversi Vol 8, No 1 (2019): April 2019
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/k.v8i1.6512

Abstract

Abstrak- Desa ranggang merupakan sentra produksi arang kayu di Kalimantan Selatan. Arang kayu diproduksi dalam tungku dari tanah liat berbentuk kubah dengan diameter sekitar 4 meter dan tinggi 3-4 meter. Di Desa Ranggang ini terdapat lebih dari 500 buah tungku dengan kapasitas produksi arang kayu sekitar 2-3 ton arang/tungku untuk tiap kali produksi. Asap yang keluar dari tungku arang pada proses produksi arang jumlahnya sangat besar selama ini terlepas ke lingkungan yang berpotensi menimbulkan polusi udara dan mengganggu pengrajin arang tersebut.. Penelitian tentang potensi asap cair sebagai produk samping pembuatan arang kayu desa ranggang tersebut dilakukan dengan memodifikasi model tungku arang desa Ranggang berupa penambahan instalasi kondensasi asap pada bagian knalpot tungku. Tungku arang percontohan telah dibuat dengan kapasitas produksi 3 ton arang setiap kali produksi. Bahan baku yang digunakan adalah limbah kayu ulin (Eusideroxylon zwageri Teijsm. & Binn.). Asap cair yang diperoleh dari tungku tersebut sejumlah 47 liter untuk setiap kali produksi. Asap cair yang dihasilkan didominasi fraksi suhu 95-105 0C, yaitu sebanyak 81%, memiliki kadar  asam (dihitung sebagai asam asetat) 0,825 molar dengan pH berkisar. 2,91-3,08. Kata kunci: asap cair, produk samping, produksi arang, kondensasi asap dan tungku arang Ranggang
PENENTUAN WAKTU REAKSI DAN JUMLAH KATALIS (H2¬SO4 DAN KOH) OPTIMUM PADA PEMBUATAN BIODIESEL DARI MINYAK GORENG BEKAS Abdullah Abdullah; Dorothy Eka Ria; Uripto Trisno Santoso; Kholifatu Rosyidah
INFO-TEKNIK Vol 11, No 1 (2010): INFOTEKNIK VOL. 11 NO. 1 2010
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/infotek.v11i1.1768

Abstract

Research of determination of optimum reaction time and number of catalyst (H2SO4 and KOH) at biodiesel production from waste cooking oil had been done. Aim of this research is to get the optimum reaction time and number of catalyst (H2SO4 and KOH), and the main chemical compound of biodiesel from waste cooking oil. Biodiesel from waste cooking oil is made from esterification reaction using H2SO4 2% w/w as acid catalyst, continued by transesterification reaction using KOH as base catalyst. The variables which is used in the research were the reaction time of esterification (45, 90, and 135 minutes) and transesterification (60, 120, and 180 minutes), while variation number of acid catalyst were 0,5; 1,0; 1,5 ml and base catalyst were 0,5; 1,0; 1,5 g. The optimum reaction time and number of catalyst were determined based on biodiesel characteristics are acid number, kinematics viscosity, and density. The characteristics were compared with waste cooking oil characteristic and SNI standard for biodiesel. Main chemical compound was determined by GC-MS instrument. Based on the research result obtained the optimum quality of methyl ester with acid number was 0,19 mg KOH/g, kinematics viscosity (40oC) was 4,51 mm2/s, and density was 0,875 g/ml. Concluded that the reaction time of esterification was 90 minutes and transesterification was 120 minutes, with number of catalyst H2SO4 2% w/w was 0,5 ml and KOH was 1,0 g for oil was 50 ml. Main chemical compound of biodiesel were  methyl lauric, methyl myristic, methyl palmitic, and methyl oleic, respectively.
KEPRAKTISAN PERANGKAT PEMBELAJARAN DENGAN MODEL PEMBELAJARAN INKUIRI TERBIMBING PADA MATERI MATERI ZAT ADITIF DAN ZAT ADIKTIF Kiki Miranti; Syahmani Syahmani; Uripto Trisno Santoso
Journal of Banua Science Education Vol 2, No 1: 2021
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (325.7 KB) | DOI: 10.20527/jbse.v2i1.61

Abstract

Students in Indonesia have problems in critical reading competence and understanding in the field of science in the form of misconceptions. This is indicated by the fact that students in Indo-nesia are only able to solve routine problems and will have difficulty when faced with unusual problems. In addition, this problem is also exacerbated by the unavailability of laboratory facili-ties and the process of critical thinking skills has not been implemented properly. The purpose of this study was to develop science learning tools to improve the critical thinking skills of junior high school students on additive and addictive substances. This study uses the development of learning tools with the Tessmer model. Starting from the self-evaluation stage, prototyping (vali-dation, evaluation/FGD, and revision), then field test. The learning tools developed include the syllabus, lesson plans, teaching materials, LKPD, assessment sheets, and LP to practice critical thinking skills. Data collection techniques were carried out through observation, teacher and student activities, documentation, and tests of learning outcomes and critical thinking. The trial subjects were 51 people who were divided into 3 stages of prototype testing with different stu-dents at each stage. The results of the development and research show that the learning tools de-veloped are considered practical so that they are feasible to use. The results of the research find-ings are that there is a tendency for the initial knowledge level of students to be weak and low concept understanding caused by interest in learning and low literacy levels.Keywords: guided inquiry, science, critical thinking skills, development research. AbstrakPeserta didik di Indonesia mempunyai permasalahan dalam kompetensi membaca kritis dan pemahaman pada bidang studi IPA dalam bentuk miskonsepsi. Hal ini ditunjukkan dengan peserta didik di Indonesia hanya mampu menyelesaikan permasalahan rutin dan akan mengalami kesulitan ketika menghadapi masalah yang tidak biasa. Selain itu permasalahan ini juga diperparah dengan tidak tersedianya fasilitas laboratorium dan proses keterampilan berpikir kritis belum dilaksanakan dengan baik. Tujuan dari penelitian ini adalah untuk mengembangkan perangkat pembelajaran IPA untuk meningkatkan keterampilan berpikir kritis peserta didik SMP pada materi zat aditif dan adiktif. Penelitian ini menggunakan pengembangan perangkat pembelajaran dengan model Tessmer. Mulai dari tahap Self-evaluation, prototyping (validasi, evaluasi/FGD, dan revisi), kemudian field test. Perangkat pembelajaran yang dikembangkan meliputi silabus, RPP, materi ajar, LKPD, lembar penilaian, dan LP untuk melatihkan keterampilan berpikir kritisnya. Teknik pengumpulan data dilakukan melalui observasi, aktivitas guru dan peserta didik, dokumentasi, dan tes hasil belajar dan berpikir kritis. Subjek uji coba sebanyak 51 orang yang terbagi dalam 3 tahapan uji prototipe dengan siswa yang berbeda di tiap tahapannya. Hasil pengembangan dan penelitian menunjukkan bahwa perangkat pembelajaran yang dikembangkan dinilai praktis sehingga layak untuk digunakan. Hasil temuan penelitian yaitu ada kecenderungan tingkat pengetahuan awal peserta didik yang lemah serta pemahaman konsep yang rendah yang disebabkan oleh minat belajar dan tingkat literasi yang rendah.Kata kunci: inkuiri terbimbing, IPA, keterampilan berpikir kritis, penelitian pengembangan.
Characterization of Alginate-Cellulose-Kaolin Composites for Slow-Release Urea Fertilizer Sunardi Sunardi; Gusti Nia Faramitha; Uripto Trisno Santoso
Indonesian Journal of Chemical Research Vol 8 No 3 (2021): Edition for January 2021
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598//ijcr.2021.8-sun

Abstract

Research on the effect of cellulose and kaolin addition to alginate-cellulose-kaolin composites' characteristics as a slow-release agent of urea fertilizer has been done. The technique used in composites' preparation is an extrusion technique using 2% CaCl2 solution as a cross-linker. The compositions of alginate-cellulose-kaolin were varied to determine their effect on composites' characteristics such as diameter, color, swelling ratio, entrapment efficiency, and release of urea. The results showed that the diameter of beads in wet condition produced ranges from 2.98 to 3.54 mm, whereas the diameter of dry beads ranges from 1.22 to 1.92 mm. The addition of cellulose and kaolin affected the color of the beads produced based on CIE Lab analysis. The value of the swelling ratio decreased with the addition of cellulose and kaolin. The entrapment efficiency of urea in beads obtained ranged from 37.25 to 45.06%. The release of urea in aqueous media showed that cellulose and kaolin's addition into the alginate affected the amount of released urea.