Article Per Year (5 Year)
p-Index From 2020 - 2025
4.467
P-Index
This Author published in this journals
All Journal Jurnal Periodic Jurusan Kimia UNP Jurnal Penelitian Pendidikan IPA (JPPIPA) Pelita Eksakta MASALIQ: Jurnal Pendidikan dan Sains SAINTI: Majalah Ilmiah Teknologi Industri Jurnal Pendidikan MIPA
Nizar, Umar Kalmar
Unknown Affiliation
Religion Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Control & Systems Engineering Education Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Physics Social Sciences Other

Published : 34 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 34 Documents
Search

 1   2   3   4 
Determination of Levels of Iron (Fe) and Mercury (Hg) in Atomic Absorption Spectrophotometry (AAS) in Outlet Waste Water Sari, Risma; Gusvita, Nola; Nizar, Umar Kalmar; Banon, Charles
JURNAL ILMIAH TEKNOLOGI INDSUTRI (SAINTI) Vol 20, No 1 (2023): VOL 20 NO 1 JUNI 2023
Publisher : Politeknik ATI Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.52759/sainti.v20i1.194

Abstract

Wastewater is a contemporary problem as population density increases. Every household living in urban areas will definitely need a waste water disposal site. This research was conducted to determine the levels of iron and mercury. This is done to ensure that the levels of ferrous metal and mercury in the outlet comply with predetermined requirements. The side effect of metal iron and mercury is that if the outlet contains too many levels, the outlet cannot be channeled directly to residential areas, which if released can endanger the health of the community. Quantitative tests were carried out to determine iron content using the flame atomic absorption spectrophotometry method at a wavelength of 248.3 nm and to determine mercury content using the Mercury Vaporizer Unit (MVU) method using atomic absorption spectrophotometry at a wavelength of 253.7 nm. The results of testing for ferrous metal levels in the outlet sample were 0.1969 mg/L. Meanwhile, the mercury level in the outlet sample was 0.0012 mg/L, based on Minister of Environment and Forestry RI No. 05 of 2014 it can be concluded that the levels of ferrous metal (Fe) and mercury (Hg) contained in the outlet wastewater are below the established environmental quality standards.
Studi Pemanfaatan Rumput Liar Pekarangan Rumah sebagai Bahan Baku Pembuatan Ekoenzim Syafriadi, Riko; Nizar, Umar Kalmar; Stiadi, Della Rosalynna; Zuyyina, Himla; Fitriani, Fitriani; Fika, Miva Hemalia; Fadhila, Radhiatul; Syafri, Vanny Sofiana
Periodic Vol 14, No 2 (2025): PERIODIC
Publisher : Departemen Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/periodic.v14i2.133838

Abstract

Wild grass is a plant that grows unwanted in certain areas such as fields, gardens, agricultural land and yards. This plant is generally discarded and rarely used. Based on the composition of the materials used in ecoenzymes, fresh wild grass plants have great potential to be used as raw materials for ecoenzymes. This study aims to determine the characteristics of ecoenzymes produced using wild grass from home gardens, such as fragrant nutsedge (Cyperus aromaticus var. Elatus), virginica grass (Leersia virginica), Belulang grass (Eleusine indica), Peking grass (Agrostis stolonifera) and Ilalang (Imperata cylindrica). Wild grass with a certain composition is mixed with brown sugar and water in a ratio of 3: 1: 10 in five containers. The ecoenzyme manufacturing process is carried out for 90 days and changes in color, odor, and pH of the ecoenzyme product are observed. The results of this study indicate that the color of the five ecoenzymes produced shows a change in color to become more cloudy than the initial color of the ecoenzyme. The odor of the five ecoenzymes produced showed a change in odor to become more sour in the third month like the typical odor of weeds. Meanwhile, the pH of the ecoenzymes produced ranged from 5.8 to 7.8. The high pH of the ecoenzymes produced was caused by the low organic acid content of the ecoenzymes produced. In addition to observing the physical condition and pH of the ecoenzymes produced, qualitative testing of the nutrient content in the form of N, P and K was also carried out. Testing of the nutrient content of N, P and K carried out showed that the ecoenzymes produced from home yard weeds contained the nutrients N, P and K. These results indicate that the ecoenzymes produced can also be used as liquid organic fertilizers
Potensi Karbon dari Bunga Cemara Laut (Casuarina Equisetifolia) sebagai Sumber Material Maju berdasarkan Hasil Uji Proksimat Novel, Dheo Shalsabilla; Putri, Natasya Alya; Karsa, Dion Randi; Izanel, Rezi Ananta; Jannah, Miftahul; Khaliq, Feni Kurnia; Nizar, Umar Kalmar
Periodic Vol 14, No 2 (2025): PERIODIC
Publisher : Departemen Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/periodic.v14i2.130328

Abstract

This study explores the potential of Sea Pine Flowers from Pantai Pasir Jambak, Kota Padang, as a carbon source for advanced materials through carbonization. Carbon is generated by the incomplete carbonization process, which breaks down organic components. It can be obtained from organic waste materials that contain cellulose, hemicellulose, and lignin. Carbonization was performed at 350˚C for durations of 1 hour, 1.5 hours, 2 hours, and 2.5 hours. Analysis results revealed vapor content ranging from 2.18% to 2.69%, ash content from 4.44% to 8.06%, and bound carbon content from 89.25% to 92.88%. The highest bound carbon content was achieved at 350˚C for 1 hour (C-60). All results meet the SNI 06-3730-1995 standards. Low vapor and controlled ash content indicate high-quality carbon. This study confirms that Sea Pine Flowers have significant potential for advanced material applications as a high-quality carbon source.
Pemanfaatan Karbon Batang Jagung (Zea mays) untuk Penjernihan Minyak Jelantah Karsa, Dion Randi; Putra, Ananda; Sanjaya, Hary; Novel, Dheo Shalsabilla; Izanel, Rezi Ananta; Putri, Natasya Alya; Khaliq, Feni Kurnia; Jannah, Miftahul; Nizar, Umar Kalmar
Periodic Vol 14, No 2 (2025): PERIODIC
Publisher : Departemen Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/periodic.v14i2.130330

Abstract

Used cooking oil, which is often discarded carelessly, can cause environmental pollution and adversely affect health if consumed again. This study explored the use of activated carbon produced from corn stalks (Zea mays) for the purification of used cooking oil. Activated carbon was produced through chemical activation using NaOH and applied to used cooking oil in various treatments, including combination with cornstarch. The quality of the purified oil was evaluated based on density, flow rate, saponification number, and acid number. The results of this study are expected to provide an environmentally friendly solution in the treatment of used cooking oil waste and utilize corn stalk waste effectively, thereby reducing negative impacts on the environment and improving public health.The result of this study is activated carbon from corn stalks which is able to reduce the density of 0.83 g/mL with cornstarch adsorbent, flow rate of 0.201 ml/s with carbon adsorbent, acid number of 5.31 mg/KOH with carbon adsorbent, saponification number of 139.46 mg/KOH.
Optimasi Desorpsi Kation Pb2+ dari Adsorben Silika Gel-GPTMS (Glycidoxypropyltrimethoxysilane) Termodifikasi Sulfonat dengan Metode Kolom Auzakiyah, Sabella; Oktavia, Budhi; Sanjaya, Hary; Nizar, Umar Kalmar
Periodic Vol 14, No 2 (2025): PERIODIC
Publisher : Departemen Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/periodic.v14i2.133061

Abstract

Silica gel is a material that has two active sides, namely silanol (Si-OH) and siloxane (Si-O-Si) groups, but it is less effective as an adsorbent so it needs to be modified. Modification was carried out by adding sulfonate groups using GPTMS bridging compounds to improve the ability of silica gel to adsorb metal ions, such as Pb²⁺ cations. Characterization was performed using FTIR (Fourier Transform-Infrared) and XRF (X-Ray Fluorescence) to ensure the success of the modification process, while SSA (Atomic Absorption Spectrophotometry) was used to measure the effectiveness of the adsorption and desorption processes. In this study, adsorption and desorption were carried out using the column method. Adsorption of Pb²⁺ cation was carried out using silica gel-GPTMS sulfonate adsorbent at optimum conditions of 20 ppm concentration and pH 3. The process was followed by desorption to determine the optimum conditions, including the type of desorption agent (NaCl and CaCl₂), concentration, and flow rate. The results showed that the optimum conditions were obtained with CaCl₂ desorption agent, with a desorbed weight of 0.1707 mg and a desorption efficiency of 98.67%. The optimum concentration of CaCl₂ was 0.05 M with a desorbed weight of 0.1730 mg and a desorption efficiency of 100%. In addition, the optimum flow rate was 1 mL/min with a desorption percentage of 100%.
Flipped Classroom with Guided Inquiry on Buffer Solutions via Discord: A Study of Learning System Development Harahap, Aprilia Silviani; Mawardi, Mawardi; Suryani, Okta; Nizar, Umar Kalmar; Akmar, Reza
Jurnal Penelitian Pendidikan IPA Vol 11 No 8 (2025): August
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v11i8.12350

Abstract

This research aims to design a flipped classroom learning system incorporating guided inquiry, using the Discord platform for buffer solution materials in Phase F. The study employed Plomp Educational Design Research framework, which comprises initial investigation, design, construction, testing, evaluation, and refinement. The product underwent validation through expert evaluation and was assessed for practicality and effectiveness. The content validity achieved a score of 0.89, while the media validity scored 0.90, meaning both belong to the valid category. Evaluation of practicality showed that the system was highly practical, with teachers and students giving it an overall score of 90% and 92% respectively. Effectiveness was measured by analyzing pretest and posttest results using the N-Gain formula, yielding a score of 0.75, which is classified as high gain. The overall findings suggest that the developed learning system is valid, practical, and effective in enhancing students’ understanding of buffer solutions. Moreover, the integration of Discord provides an accessible and interactive digital environment, aligning with the needs of 21st-century education and the Merdeka Curriculum. Therefore, this model can be recommended as an innovative solution for digital chemistry instruction in senior high schools.
Pemanfaatan Karbon Aktif Daun Serai (Cymbopogon citratus) dan Bleaching Earth dalam Penjernihan Minyak Jelantah Yanti, Fetria Rahayu Wendi; Nizar, Umar Kalmar
MASALIQ Vol 5 No 3 (2025): MEI
Publisher : Lembaga Yasin AlSys

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.58578/masaliq.v5i3.6036

Abstract

Used cooking oil is a household waste with the potential to pollute the environment and pose health risks if discarded improperly or reused without adequate treatment. This study aims to purify used cooking oil through a two-stage adsorption method using activated carbon derived from lemongrass leaves and Bleaching Earth. In the first stage, activated carbon was synthesized from lemongrass leaves calcined for 60 minutes and activated with 2N NaOH solution, followed by the addition of Bleaching Earth in the second stage. The quality of the oil before and after purification was assessed through analyses of density, acid number, saponification value, moisture content, and infrared spectrum (FTIR). The results indicate that activated carbon calcined for 60 minutes (MJ-C60) yielded the best outcome, reducing density to 0.9414 g/mL, lowering moisture content from 0.34% to 0.16%, and increasing the saponification value from 41.5650 to 63.7075 mg KOH/g. The acid number also decreased from 13.2302 to 8.3288 mg KOH/g. FTIR analysis revealed the presence of ester C=O groups around 1743 cm⁻¹ and aliphatic C–H absorption bands at 2850–2950 cm⁻¹, indicating that the triglyceride structure remained intact. These findings demonstrate that the combination of activated carbon from lemongrass leaves and Bleaching Earth is effective in improving the clarity and physicochemical quality of used cooking oil, while offering an environmentally friendly solution based on organic waste utilization.
Peningkatan Pemurnian Minyak Jelantah melalui Sistem Adsorben Ganda: Bleaching Earth dan Karbon dari Kulit Buah Kakao (Theobroma cacao L) Utami, Esssylia Afriyanti; Nizar, Umar Kalmar; Etika, Sri Benti
MASALIQ Vol 5 No 3 (2025): MEI
Publisher : Lembaga Yasin AlSys

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.58578/masaliq.v5i3.6039

Abstract

Used cooking oil (minyak jelantah) is a household and industrial waste product that poses environmental risks and undergoes significant quality degradation due to the breakdown of chemical compounds during repeated use. This study aims to evaluate the effectiveness of a combination of activated carbon derived from cocoa pod husk waste and bleaching earth in improving the quality of used cooking oil. The research was conducted experimentally in the laboratory of Universitas Negeri Padang using used cooking oil obtained from local vendors. Activated carbon was prepared by calcining cocoa pod husks at 350°C for varying durations of 30, 45, 60, and 75 minutes, followed by activation with 1M NaOH solution. The purification process was carried out in stages through the addition of activated carbon and bleaching earth under controlled heating conditions. Parameters analyzed included acid number, moisture content, density, saponification value, and functional group characterization using infrared spectroscopy (FTIR). The results indicate that the most effective adsorbent combination was achieved with activated carbon calcined for 60 minutes, which reduced the acid number from 14.92 to 5.09 mg KOH/g, decreased moisture content to 0.11%, and increased the saponification value to 75.30 mg KOH/g. The FTIR spectrum showed reduced intensity in functional groups associated with degradation, indicating effective purification. In conclusion, the combination of activated carbon from cocoa pod husk waste and bleaching earth is proven effective in improving the physicochemical quality of used cooking oil, while also demonstrating the potential for sustainable and environmentally friendly use of agricultural waste as raw material for adsorbents.
Optimasi Waktu Kalsinasi Karbon Aktif dari Bunga Cemara Laut (Casuarina equisetifolia) dalam Kombinasi dengan Bleaching Earth untuk Pemurnian Minyak Jelantah Fadila, Radhiatul; Nizar, Umar Kalmar
MASALIQ Vol 5 No 3 (2025): MEI
Publisher : Lembaga Yasin AlSys

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.58578/masaliq.v5i3.6040

Abstract

Used cooking oil is a byproduct of repeated frying processes that undergoes quality degradation due to continuous oxidation and heating, resulting in harmful compounds such as free fatty acids, peroxides, and polymers. This study aims to evaluate the effectiveness of purifying used cooking oil using a combination of two adsorbents: activated carbon derived from Casuarina equisetifolia (beach she-oak) flowers activated with NaOH, and bleaching earth. Activated carbon was synthesized through calcination at varying durations of 45, 60, 75, and 90 minutes to determine the optimal condition. The oil quality was evaluated by measuring acid number, saponification value, density, moisture content, and functional group analysis using infrared spectroscopy (FTIR). The results indicate that activated carbon calcined for 60 minutes produced the best outcomes, reducing the acid number from 14.92 to 5.07 mg KOH/g, increasing the saponification value to 43.33 mg KOH/g, achieving a density of 0.8693 g/mL in accordance with national standards (SNI), and reducing moisture content to 0.4330%. FTIR analysis showed decreased intensity in carbonyl groups and the disappearance of hydroxyl groups, indicating effective removal of polarized and oxidized compounds. These findings demonstrate that the combination of activated carbon from Casuarina equisetifolia flowers and bleaching earth is an effective and environmentally friendly purification method, supporting the sustainable use of biomass waste as adsorbent material.
Development of Chemical Equilibrium E-Module Guided by 5E Instructional Model with Interactive Virtual Laboratory Lubis, Amalia Putri; Ellizar, Ellizar; Zainul, Rahadian; Nizar, Umar Kalmar
Jurnal Pendidikan MIPA Vol 23, No 1 (2022): Jurnal Pendidikan MIPA
Publisher : FKIP Universitas Lampung

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

Abstract

E-module is a form of electronic teaching material that can be used independently, with each learning activity connected by a link. 5E Instructional Model is a learning model that was developed based on constructivism learning, where students construct their own knowledge and are actively involved in every stage of the learning process. This study aims to develop a chemical equilibrium e-module based on an integrated 5E instructional virtual laboratory, as well as to determine the level of validity and practicality. The development of the e-module is carried out through the Plomp model stage which consists of 3 stages, namely preliminary research, prototyping phase, and assessment phase. The assessment instruments used are observation sheets and questionnaires. The results showed that the e-module developed was valid and practical so that it could be used in the learning process.Keywords: e-modul, 5E instructional model, chemical equilibriumDOI: http://dx.doi.org/10.23960/jpmipa/v23i1.pp256-265
Co-Authors Afrilia, Yoni Agustin, Andre Aini, Syamsi Akmar, Reza Althof, Hasnah Sausan Andrean, Maifil Dwi Anjelia, Mariza Ardi, Ahmad Maulana Auzakiyah, Sabella Azzahra, Wenalda Hanifah Budhi Oktavia Charles Banon Della Rosalynna Stiadi Deski Beri Desy Kurniawati Edi Nasra Ellizar ellizar Fadhila, Radhiatul Fadila, Radhiatul Fika, Miva Hemalia Fitri Amelia Fitriani Fitriani Gusvita, Nola Handri, Silvi Hapzi Ali Harahap, Aprilia Silviani Hardeli Hardeli Hardeli Hary Sanjaya Indang Dewata Istiqamah, Siti Sarah Izanel, Rezi Ananta Karmila, Aroma Karsa, Dion Randi Khaliq, Feni Kurnia Lubis, Amalia Putri Mawardi Miftahul Jannah Miftahul Khair Miftahurrahmi, Miftahurrahmi Minda Azhar Muhammad Farhan Mukhaiyar, Riki Novel, Dheo Shalsabilla Novela, Riana Novriansyah, Edo Pernadi, Niza Lian Putra, Ananda Putri, Natasya Alya Putri, Yunisa Anugrah R, Yoanatul Hasanah Raden Mohamad Herdian Bhakti Rahadian Zainul Rahmi Rahmi Rahmi, Fathaniah Raviqa Rahmi, Maulidia Arsyta Riga, Riga Risma Sari, Risma Rizki, Suci Yulia Sabrina, Joya Sari, Trisna Kumala Sherly Kasuma Warda Ningsih Sidiq, Aqil Marsya Simbolon, Ranita Sri Benti Etika Suryani, Okta Suryelita, Suryelita Syafri, Vanny Sofiana Syafriadi, Riko Utami, Esssylia Afriyanti Veronita, Silvi Wulandari, Yolanda Yanti, Fetria Rahayu Wendi Yuliani, Amelinda Zulhendra, Zulhendra Zuyyina, Himla