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THE EFFECTS OF CHANGING MEMBRANE COMPOSITIONS AND INTERNAL ELECTROLYTES ON THE RESPON OF POTASSIUM ION SENSOR Ulianas, Alizar; Heng, Lee Yook
Sainstek : Jurnal Sains dan Teknologi Vol 7, No 1 (2015)
Publisher : IAIN Batusangkar

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (161.892 KB) | DOI: 10.31958/js.v7i1.119

Abstract

A study on the changing of membrane compositions and internal solution towards the response potassium ion sensor was carried out. Potassium ion sensor based on photocured cross linking poly(n-butyl acrylate) membranes with varying composition of valinomycin (val), sodium tetrakis [3.5-bis(trifluoro-methyl) phenyl] borat (NaTFPB), types ion of internal solution were investigated. Effects of varying composition of val, NaTFPB, types and concentration of internal solution were observed on potassium ion sensor. The effect of higher val composition was lower LOD, wider linear range, lower sensitivity but increase selectivity. Higher NaTFPB compositions lead to lower LOD, higher sensitivity and selectivity. The effect of changing internal electrolyte lead to lower LOD, wider linear response range and higher selectivity according to internal electrolyte consisting Na+, Ca2+ and K+, and sensitivity increase following internal electrolyte with Ca2+, K+ and Na+.Key words: ion sensor, ion selective membrane, ionofor, lipofilik salt
Sintesis Membran Molecularly Imprinted Polymers (MIPs) dan Karakterisasinya sebagai Bahan Penyerap Asam Urat Atika, Rahma; Ulianas, Alizar
Periodic Vol 8, No 2 (2019): PERIODIC
Publisher : Jurusan Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (23.431 KB) | DOI: 10.24036/p.v8i2.108805

Abstract

MIPs is an polymers that have cavities release the template molecules. The cavity serves to separate the analyte by recognizing target molecules based on their shape, size, structure, physical and chemical properties. MIPs have a high level of sensitivity and selectivity. In the review of this article, it is discussed about membrane synthesis MIPs, the effect of uric acid solution pH and optimizaton time on the adsorption of MIPs. Power capability MIPs adsorption of uric acid was analyzed using FTIR (Fourier Transform Infra Red). Based on article review that MIPs are able to adsorbtion uric acid seen from the peak adsorption of C=O and C-N groups in the area 1673 cm-1 and 1290 cm-1 region which are characteristic of the amides found in MIPs reextraction. Whereas in the extraction MIPs there was no peak adsorption of the C-N group. Peak adsorption this C-N group is only owned by pure uric acid and is not present in MIPs. In addition there is influence significant adsorption of MIPs against uric acid with differences in adsorption time and pH uric acid solution. MIPs can be applied to adsorb uric acid in blood samples.
Sintesis Membran Molecularly Imprinted Polymers (MIPs) dengan Metoda Photopolimerisasi sebagai Bahan Penyerap Glukosa Pihanda, Febi Aulia; Ulianas, Alizar
Periodic Vol 8, No 2 (2019): PERIODIC
Publisher : Jurusan Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (23.431 KB) | DOI: 10.24036/p.v8i2.108769

Abstract

MIPs are specific molecular identification polymer molds that are sensitive to their template molecules. The purpose of this discussion is to find out how to synthesize and characterize glucose MIPs membranes, optimum conditions for absorption of MIPs against glucose and application of Glucose MIPs. Based on literature, MIPs resulting from synthesis have a physical form in the form of solids. FTIR test results on MIPs are good, namely the appearance of O-H groups that indicate the presence of hydrogen bonds that can bind the template molecule in the form of glucose, in this discussion appears at wave number 3483,56 cm-1. The absorption capacity of MIPs for glucose can be influenced by the amount of MIPs, pH of glucose solution. Besides MIPs can be used to absorb glucose from the urine.
Pengembangan Lembar Kerja Peserta Didik (LKPD) Berbasis Project Based Learning Pada Materi Kimia Hijau Fase E SMA Kurnia, Febri; Ulianas, Alizar
Jurnal Pendidikan Tambusai Vol. 7 No. 2 (2023): Agustus 2023
Publisher : LPPM Universitas Pahlawan Tuanku Tambusai, Riau, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/jptam.v7i2.7786

Abstract

Tujuan dari penelitian ini adalah mengembangkan bahan ajar berupa LKPD berbasis Project Based Learning pada materi kimia hijau fase E SMA dan menilai validitas serta praktikalitasnya. Lembar kerja peserta didik yang dikembangkan menggunakan model pengembangan plomp dengan tahapan antara lain penelitian pendahuluan (preliminary research) dan pembentukan prototipe (prototyping phase). Hasil analisis validasi dihitung dengan rumus Aiken's V dan hasil analisis kepraktisan dihitung menggunakan persentase kepraktisan. Hasil validasi adalah nilai V dengan rata-rata 0.85 dengan kategori valid. Hasil praktikalitas oleh peserta didik adalah 88% dengan kategori sangat praktis dan hasil praktikalitas oleh guru adalah 88% dengan kategori sangat praktis. Hasil akhir dari penelitian ini adalah bahan ajar berupa LKPD berbasis PjBL yang memenuhi kriteria valid dan praktis.
Pengembangan Lembar Kerja Peserta Didik (LKPD) Kimia Hijau Berbasis Problem Based Learning Untuk Fase E Zai, Nestalista Forniat; Ulianas, Alizar
Jurnal Pendidikan Tambusai Vol. 7 No. 3 (2023): Desember 2023
Publisher : LPPM Universitas Pahlawan Tuanku Tambusai, Riau, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/jptam.v7i3.10472

Abstract

Tujuan dari penelitian ini adalah menghasilkan bahan ajar yang mengaplikasikan Problem Based Leaning (PBL) pada LKPD kimia hijau, serta menilai validitas dan praktikalitas LKPD yang dihasilkan. Penelitian ini menggunakan model pengembangan 4-D. Model 4-D terdiri empat tahapan yaitu tahapan define (pendefenisian), design (perancangan), develop (pengembangan), disseminate (penyebaran). Tetapi dalam penelitian ini dilakukan sampai pada tahap pengembangan. Instrumen penelitian yang dipakai meliputi lembar wawancara, angket validitas, dan angket kepraktisan. Penelitian dilakukan di Laboratorium FMIPA UNP dan SMA Pembangunan Laboratorium UNP. Indeks Aiken's V digunakan untuk menganalisis data hasil validasi, sedangkan persentase kepraktisan digunakan untuk menganalisis data kepraktisan. Berlandaskan pada hasil pengolahan data angket validitas, diperoleh kesimpulan bahwa LKPD kimia hijau berbasis pendekatan pembelajaran berbasis masalah dinyatakan valid, yang ditunjukkan dengan nilai V sebesar 0,89 yang berkategori valid, kemudian hasil analisis uji praktikalitas guru nilai NP sebesar 99%, kategori sangat praktis dan peserta didik diperoleh nilai NP sebesar 83% dengan kategori praktis.
Pengaruh pH Pada Penentuan Ion Logam Fe3+ Secara Anodic Stripping Voltammetry Menggunakan Pencil Lead Electrode Modifikasi Lapisan Tipis Emas Akhmad, Ashta Varan; Sari, Trisna Kumala; Ulianas, Alizar; Suryani, Okta
Periodic Vol 13, No 2 (2024): PERIODIC
Publisher : Departemen Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/periodic.v13i2.124502

Abstract

Fe3+ metal ions have been electrochemically detected using a pencil lead electrode modified with gold thin layer. The modification of the gold thin layer is carried out by sweeping-potential electrodeposition using the cyclic voltammetry method. The purpose of this study was to determine the optimum pH conditions for measuring Fe3+ metal ions using HNO3 as a supporting electrolyte. The pH optimization is carried out using the Anodic Stripping Voltammetry (ASV) method. This technique involves a pre-concentration step where Fe3+ is reduced to Fe0 on the electrode surface in HNO3, followed by a stripping step in ASV where Fe0 is oxidized back to Fe3+. The results showed that HNO3 with pH 1 is the optimum pH for measuring Fe3+ metal ions using Au/PLE electrodes with a test analyte concentration of 250 μM. The anodic peak of the Fe3+ metal ion appears at a potential of 0.55 V.
Sintesis Polianilin (PANI) yang di Doping Besi (III) Oksida Menggunakan Metode Fotopolimerisasi Nofianti, Nora; Ulianas, Alizar; Kurniawati, Desy
Periodic Vol 12, No 3 (2023): PERIODIC
Publisher : Departemen Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/periodic.v12i3.118033

Abstract

This study aims to increase the electrical conductivity of the aniline synthesis product with added dopant. Polyaniline conductive polymer synthesis was carried out with aniline monomer mixed with Ethylene Glycol Dimethacrylate (EGDMA) as crosslinker, Dimethoxy phenylacetophenone (DMPP) as initiator, Fe2O3 as dopant. The polymer results were tested for electrical conductivity using a Four Point Probe (FPP) and characterized by Fourier Transform Infrared (FTIR), Uv-vis DRS (Uv-visible Diffuse Reflectance). the composition that showed the highest conductivity was the addition of Fe2O3 dopant as much as 0.0283 g with an electrical conductivity value of 17.0609 x 10-3 S/cm.
Photopolymerization of Imprinted Polymer with Dummy Template for the Recognition of Hydroquinone in Aqueous Medium Musali, Norlin Suhaiza; Abu Bakar, Norlaili; Abdul Rahim, Nurulsaidah; Wan Mahamod, Wan Rusmawati; Hashim, Norhayati; Mohd Sharif, Sharifah Norain; Che Soh, Siti Kamilah; Ulianas, Alizar
Indonesian Journal of Chemistry Vol 24, No 5 (2024)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.90096

Abstract

This study' purposes are to synthesize molecularly imprinted polymer (MIP) with hydroxyethyl methacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA) using p-xylene under ultraviolet curing at 405 nm for the recognition of hydroquinone (HQ) in aqueous medium. The template was extracted from the polymer with a mixture of methanol and acetic acid (9:1) by volume (v/v). The Fourier transform infrared (FTIR) spectrum of MIP (after wash) showed the absence of peak at the range of 840–860 cm−1, which represented the stretching outside the aromatic plane C–H at the para position (p-xylene). Field emission scanning electron microscope (FESEM) micrograph showed that the MIP had cavities compared to non-imprinted polymer (NIP). The MIP (MIP-Pxy) with ratio (monomer:crosslinker) 0.25 and 1.00% template gave the highest uptake of hydroquinone (HQ) in aqueous solution, which implied more specific recognition (highest KD value). The rebinding of HQ onto MIP-Pxy was best described by both isotherm (Langmuir and Freundlich) and kinetic model (pseudo-first and -second). The MIP was successfully synthesized using p-xylene, able to recognize HQ and was very selective to p-CP. Implication of the study, the synthesized MIP can be used for recognition and sensing materials for HQ and any similar molecules.
EFFECTIVENESS OF A PROBLEM-BASED LEARNING MODULE ON SALT HYDROLYSIS IN IMPROVING STUDENT LEARNING OUTCOMES Batu Bara, Humairoh Azhari; Mawardi, Mawardi; Akmar, Reza; Ulianas, Alizar; Suryani, Okta; Aini, Faiza Qurrata; Mulyanti, Mulyanti
Chimica Didactica Acta Vol 12, No 2: December 2024
Publisher : FKIP USK

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jcd.v12i2.41972

Abstract

This study aimed to analyze the effectiveness of the problem-based learning module on students' learning outcomes at SMAN 1 Bukittinggi. This study employed Plomp's development model. The research applies a quasi-experimental type with a non-equivalent control group design. The population includes phase F students of Class XI of SMAN 1 Bukittinggi who are studying chemistry in the 2023/2024 academic year as many as six classes. The sample was taken with a purposive sampling technique, and the selected classes XI F9 and XI F10. The test instrument was 20 multiple-choice questions. The data obtained were analyzed using the n-gain and hypothesis testing with the Mann-Whitney test. The results of data analysis obtained the n-gain value of the experimental class and control class, respectively, namely 0.74 with a high category and 0.58 with a medium category. As for hypothesis testing, the calculation of Asymps. Sig 0.05, then the learning outcomes of experimental class students are higher than those of the control class. The results showed that problem-based learning module learning on is effective in improving student learning outcomes at SMAN 1 Bukittingi.
Sistem Pembelajaran Discord Flipped Classroom Berbasis Guided Inquiry Dengan Literasi Digital untuk Mahasiswa Kimia Tahun Pertama Sari, Intan Nofita; Mawardi, Mawardi; Akmar, Reza; Ulianas, Alizar; Suryani, Okta
Jurnal Penelitian Pendidikan IPA Vol 11 No 9 (2025): September: In Progress
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v11i9.10213

Abstract

This study aims to develop a valid and practical learning system in addressing the need for an instructional design that fosters digital literacy in first-year chemistry students. Using the Educational Design Research framework, the learning system was developed on Discord and integrated flipped-guided inquiry learning models. The study involved lecturers and students from Department of Chemistry, Universitas Negeri Padang. The system was structured with a server and channels to facilitate each stage of the learning process. The evaluation assessed the validity and practicality of the system. The overall results indicated the system was highly valid with overall validity of 0.85 (construct validity 0.85 and content validity 0.86) and practical (student practicality 81% and lecturer practicality 83%). These findings suggest that a Discord-based, flipped-guided inquiry system is a highly viable and useful tool for teaching thermochemistry and student’s digital literacy.