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All Journal Jurnal Periodic Jurusan Kimia UNP Jurnal Penelitian Pendidikan IPA (JPPIPA) Indonesian Journal of Chemistry Pelita Eksakta Hydrogen: Jurnal Kependidikan Kimia SAINTI: Majalah Ilmiah Teknologi Industri Jurnal Pendidikan MIPA
Nizar, Umar Kalmar
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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 Other

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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%.
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
Development of REACT-Based E-Module to Improve Students' Scientific Literacy Ability in Buffer Solution Karmila, Aroma; Kurniawati, Desy; Hardeli, Hardeli; Nizar, Umar Kalmar
Jurnal Pendidikan MIPA Vol 23, No 2 (2022): Jurnal Pendidikan MIPA
Publisher : FKIP Universitas Lampung

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

Abstract

The buffer solution e-module based on the REACT strategy (Relating, Experiencing, Applying, Collaborating, Transferring) has been developed and analysed for its validity and practicality levels to assist the learning process of students to train students' scientific literacy skills. This research belongs to the type of EDR (Educational Design). Research) with the Plomp model. The research tools used were interview forms, validity questionnaires, and practicality. This e-module has been verified by six expert reviews, and 9 students became research subjects in this development research. Data were analysed using Aikens'V formula, and practicality percentage. Analysis of the validity of the questionnaire data showed an Aikens' V average score of 0.89 (for construct validity). Analysis of the practicality questionnaire data showed an average score of 83% and 83% (for small groups and field practice tests). Data analysis shows that the e-module has a high level of validity and practicality. Therefore, it can be concluded that the buffer solution e-module teaching material based on the REACT strategy is valid and practical so that it is feasible to use it in learning to train students' scientific literacy skills. Keywords: e-module, REACT strategy, buffer solution, scientific literacy DOI: http://dx.doi.org/10.23960/jpmipa/v23i2.pp866-879
Learning System with Digital Literacy Based on Guided Inquiry Integrated Flipped Classroom Using Discord Application on Colloid Handri, Silvi; Mawardi, Mawardi; Aini, Syamsi; Nizar, Umar Kalmar
Jurnal Penelitian Pendidikan IPA Vol 9 No 8 (2023): August
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v9i8.4471

Abstract

This research aims to produce an integrated flipped classroom learning system based on guided inquiry using Discord application on colloid material for first year students using the Plomp development model developed by Tjeerd Plomp. The research instrument used a validation sheet filled in by 5 UNP chemistry lecturers, an interview sheet for assessment at the one-to-one evaluation stage which contained several questions with answers in the form of explanations from 3 students, a practicality sheet filled out by 9 students then content validity and constructs were analyzed using Aiken's V scale, and practicality was analyzed using practical percent. The results of the analysis of the content and construct validity data obtained were stated to be valid with a value of V = 0.84 and 0.91, as well as the results of the practicality test data analysis obtained a P value (%) of 93 in the very practical category. So that an integrated learning system is produced, flipped classroom based on guided inquiry using the Discord application on colloidal material which is used as an alternative method in the learning process in lectures.
Pengembangan E-Modul Sistem Koloid dengan Contextual Teaching and Learning (Ctl) Berorientasi Chemo-Entrepreneurship (Cep) untuk Meningkatkan Kemampuan Berpikir Kritis Peserta Didik Andrean, Maifil Dwi; Zainul, Rahadian; Nizar, Umar Kalmar; Kurniawati, Desy
Jurnal Penelitian Pendidikan IPA Vol 10 No 9 (2024): September
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v10i9.8546

Abstract

The high unemployment rate among high school graduates and the low critical thinking ability of high school students motivated the author to develop electronic teaching materials based on a contextual approach and oriented toward entrepreneurship. This study aims to determine the validity, practicality, and effectiveness of the e-Module on colloid system with Contextual Teaching and Learning (CTL) oriented toward Chemo-Entrepreneurship (CEP) to enhance students' critical thinking ability. The research method employed is Research and Development (R&D) using the Plomp model, which consists of the preliminary research phase, development or prototyping phase, and assessment phase. The research instruments used include validity questionnaires, practicality questionnaires and critical thinking ability test. The e-Module was validated by three lecturers from the Chemistry Department at UNP and two chemistry teachers from SMAN 6 Solok Selatan. Practicality testing was conducted with two chemistry teachers and 30 eleventh-grade students from SMAN 6 Solok Selatan. Data obtained from the validity and practicality tests were analyzed using Aiken’s V formula and practicality percentages. The validity test results showed a V value of 0.92, indicating a valid category. The analysis of the teacher practicality questionnaire showed an 86% score, categorized as very practical, while the student practicality questionnaire showed an 81% score, categorized as practical. The t-test yielded a sig (2-tailed) value of 0.026. Based on these results, it can be concluded that the developed e-Module is valid, practical, and effective in enhancing students' critical thinking skills.
Photocatalytic Degradation of Polyethylene Microplastics Using Microwave-Activated Gadolinium Oxide Catalyst Ismail, Mohammad Luqman; Hanafi, Muhammad Farhan; Zamanhuri, Norezatul Shahirah Ahmad; Sapawe, Norzahir; Nizar, Umar Kalmar; Hamid, Hairul Amani Abdul; Sidik, Siti Munirah; Ibrahim, Siti Fatimah; Danish, Mohammed
Indonesian Journal of Chemistry Vol 26, No 2 (2026)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.108052

Abstract

The persistent presence of polyethylene (PE) microplastics in aquatic environments poses serious environmental and health risks due to their resistance to conventional degradation methods. This study explores the photocatalytic degradation of PE microplastics using microwave-activated gadolinium oxide (Gd2O3) under visible light irradiation. Key operational parameters, including pH solution, catalyst dosage, and initial PE concentration were systematically investigated. Optimal degradation efficiency (68%) was achieved at pH 7, a catalyst dosage of 3 g/L, and a PE concentration of 10 mg/L. Kinetic analysis indicated that the degradation followed a pseudo-first-order model, with a maximum apparent rate constant (Kapp) of 0.0103 min−1 (R2 = 0.9782). The degradation mechanism was further elucidated using the Langmuir–Hinshelwood kinetic model, suggesting a surface-mediated reaction with a high adsorption equilibrium constant (KLH) of 0.4896 L/mg, indicating strong PE adsorption. The reduced degradation efficiency at higher PE concentrations was attributed to the limited generation of reactive oxygen species and increased light scattering. Overall, the findings demonstrate Gd2O3's potential as an efficient, environmentally benign photocatalyst, contributing significantly to the development of rare-earth-based materials for sustainable microplastic remediation in water treatment technologies.
Co-Authors Afrilia, Yoni Agustin, Andre Aini, Syamsi Althof, Hasnah Sausan Andrean, Maifil Dwi Anjelia, Mariza Auzakiyah, Sabella Azzahra, Wenalda Hanifah Baehaqi Budhi Oktavia Charles Banon Danish, Mohammed Della Rosalynna Stiadi Deski Beri Desy Kurniawati Edi Nasra Ellizar ellizar Fadhila, Radhiatul Fadila, Radhiatul Fika, Miva Hemalia Fitri Amelia Fitriani Fitriani Gusvita, Nola Hamid, Hairul Amani Abdul Hanafi, Muhammad Farhan Handri, Silvi Hapzi Ali Hardeli Hardeli Hary Sanjaya Ibrahim, Siti Fatimah Indang Dewata Ismail, Mohammad Luqman 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 Rahadian Zainul Rahmi Rahmi Rahmi, Fathaniah Raviqa Rahmi, Maulidia Arsyta Riga, Riga Risma Sari, Risma Rizki, Suci Yulia Sabrina, Joya Sapawe, Norzahir Sari, Trisna Kumala Septiani, Dhea Sherly Kasuma Warda Ningsih Sidik, Siti Munirah 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 Zamanhuri, Norezatul Shahirah Ahmad Zulhendra, Zulhendra Zuyyina, Himla