Solvent-free steam extraction of Citrus nobilis Peel essential oil: Chemical composition and bioactivity Gusliani Eka Putri, Syukri Arief, Norzawani Jaffar, Putri Dafriani, Ika Yulia Darma, Widyastuti, Vivi Sisca, Ahmad Hafizullah Ritonga, Rahadian Zainul Results in Chemistry, 2026 The essential oil (EO) from Citrus nobilis Lour. peels was extracted using the Steam-Assisted Solvent-Free Extraction (SAFE) method, a process conducted without relying on organic solvent-based systems with reduced environmental impact. Volatile compounds were characterized through gas chromatographic separation coupled with mass spectrometric detection, which revealed d -limonene to be the predominant component of the EO. The EO exhibited strong antioxidant activity, as evaluated using the DPPH method with an IC 50 of 33.64 μg/mL. In addition, antibacterial effects against Staphylococcus aureus and Escherichia coli were evaluated by the disk diffusion assay, as evidenced by the distinct absence of microbial growth surrounding the disks of 12.12 mm and 8.13 mm, respectively. The minimum inhibitory concentration (MIC) values were 15.6 μL/mL for S. aureus and 31.2 μL/mL for E. coli . These results indicate that Citrus nobilis peel EO has potential, providing bioactive components from natural sources that may be utilized in biomedical and cosmetic formulations. Notably, this work provides a detailed evaluation of the application of the SAFE method, addressing aspects that have not been fully explored in previous studies for extracting EO from fresh Citrus nobilis peels cultivated in Gunung Omeh, Indonesia. The findings demonstrate that SAFE effectively preserves bioactive constituents while offering a sustainable strategy for citrus peel waste valorization with promising antioxidant and antibacterial applications.
Oleic acid-modified zinc oxide incorporated compatibilized PLA/LLDPE nanocomposites: physical, mechanical, thermal, and morphological properties Ahmad Hafizullah Ritonga, Barita Aritonang, Debi Meilani, Herlina Herlina, Vivi Sisca, Gusliani Eka Putri, Juliandi Siregar, Enzo Wiranta Battra Siahaan South African Journal of Chemical Engineering, 2026 • Oleic acid-modified ZnO nanoparticles (O-ZnO NPs) were synthesized and subsequently incorporated into PLA/LLDPE blends via melt blending at 165°C in the presence of an LLDPE-g-OA (LO) compatibilizer. • The incorporation of 5 wt% O-ZnO NPs significantly enhanced the tensile strength, elongation at break, Young’s modulus, and thermal stability of the compatibilized PLA/LLDPE/O-ZnO (cPLO) nanocomposites. • The improved interfacial compatibility led to reduced water absorption, accelerated soil biodegradation, and effective antibacterial activity against Staphylococcus aureus . The increasing demand for safe and environmentally friendly packaging materials has driven the development of biodegradable PLA-based polymers; however, the limited mechanical strength and thermal stability of PLA restrict their broader application. This study investigates the incorporation of oleic acid–modified zinc oxide nanoparticles (O-ZnO NPs) into compatibilized PLA/LLDPE nanocomposites to improve their physical, mechanical, thermal, and morphological properties. O-ZnO NPs were synthesized via surface modification of ZnO with oleic acid (OA), resulting in improved compatibility with the polymer matrix while preserving the intrinsic crystalline structure of ZnO. Compatibilized PLA/LLDPE/O-ZnO (cPLO) nanocomposites were prepared by melt blending PLA and LLDPE in the presence of LLDPE-g-OA (LO) compatibilizer, followed by the incorporation of O-ZnO NPs at various loadings. The results demonstrate that the incorporation of O-ZnO NPs significantly enhances the nanocomposite's performance by strengthening the interfacial interactions between the immiscible PLA and LLDPE phases. Mechanical testing showed an increase in Young’s modulus from 438 MPa to 493 MPa, accompanied by an improvement in elongation at break from 43% to 54%, indicating simultaneous enhancement of stiffness and ductility. Thermal analysis revealed improved thermal stability, which is attributed to restricted polymer chain mobility and more efficient stress transfer at the filler–matrix interface. Morphological observations confirmed a more homogeneous nanoparticle dispersion and reduced phase separation within the polymer matrix. The incorporation of O-ZnO NPs reduced water absorption to 0.682% and increased biodegradation from 14.5% to 15.8% after 90 days of soil burial, indicating improved hydrophobicity while maintaining environmental degradability. The nanocomposites also exhibited antibacterial activity against Staphylococcus aureus , with inhibition zones exceeding 8 mm. O-ZnO NPs effectively improve interfacial compatibility in compatibilized PLA/LLDPE blends, resulting in balanced mechanical reinforcement and multifunctional properties suitable for semi-biodegradable packaging applications.
Hybrid polyol-based polyurethane from pine merkusii resin and polyethylene glycol 400 for sustainable asphalt modification Tamrin, Sovia Lenny, Misni Misran, Ahmad Hafizullah Ritonga, Mutiara Syaftiany South African Journal of Chemical Engineering, 2025 • PMR polyol was synthesized using formic acid and hydrogen peroxide at 40 °C, followed by separation and purification to obtain a high-purity polyol. • Hybrid polyol-based polyurethane was prepared by mixing PMR polyol, PEG-400, and toluene-2,4-diisocyanate at 40 °C, forming a crosslinked structure. • Asphalt modification was performed by incorporating hybrid polyol-based polyurethane into asphalt at 180 °C and 1000 rpm, enhancing thermal stability and structural uniformity. Biopolymer-based materials have garnered significant attention as sustainable alternatives for asphalt modification. This interest stems from their ability to improve performance while reducing environmental impact. Conventional asphalt suffers from thermal susceptibility and aging, requiring modifications to enhance durability. Polyurethane-based modifiers, synthesized from polyols, have emerged as promising solutions due to their superior mechanical and thermal properties. This study reports synthesizing and characterizing hybrid polyol-based polyurethane using Pine Merkusii Resin (PMR) as a natural polyol and polyethylene glycol 400 (PEG-400) as a synthetic polyol for sustainable asphalt modification. The research involved three stages: (1) PMR polyol synthesis via oxidation using formic acid and hydrogen peroxide, (2) polyurethane preparation through the reaction of PMR polyol, PEG-400, and toluene-2,4-diisocyanate (TDI), and (3) asphalt modification using the synthesized polyurethane. Comprehensive characterization was performed using GC–MS, FTIR, swelling tests, DSR, TGA, and SEM. GC–MS confirmed the presence of α-pinene and β-pinene in PMR polyol, indicating a high hydroxyl content. The optimal polyurethane formulation (PMR polyol: PEG-400 polyol: TDI at 35.2:8.8:56) showed the highest crosslinking density and the lowest swelling index (5.69 %). FTIR analysis identified urethane network formation at 1630–1680 cm −1 . Rheological tests revealed that asphalt–polyurethane exhibited superior resistance to rutting and cracking under heavy loads and extreme temperatures compared to conventional asphalt. The asphalt–polyurethane blend (80:20) demonstrated the highest onset temperature (459.7 °C) and the slowest degradation rate, indicating excellent thermal stability. FTIR confirmed that polyurethane was well incorporated into the asphalt matrix, while SEM showed uniform dispersion and improved structural integrity. These results highlight the potential of hybrid polyol-based polyurethane as an eco-friendly and durable asphalt modifier.
Green synthesis of cerium oxide nanoparticles using Citrus nobilis Lour. Peel extract and evaluation of their potential as antibacterial and antioxidant agents Gusliani Eka Putri, Arniati Labanni, Syukri Arief, Putri Dafriani, Ika Yulia Darma, Sri Handayani, Widyastuti, Norzawani Jaffar, Marsal Mahmud, Ahmad Hafizullah Ritonga Case Studies in Chemical and Environmental Engineering, 2025 Cerium oxide nanoparticles (CeO 2 NPs) have been synthesized using Siam oranges ( Citrus nobilis Lour.) peel extract as a capping agent with varied concentration. X-ray diffraction (XRD) analysis confirmed the formation of cubic fluorite crystal structured CeO 2 NPs. Scanning electron microscope (SEM) and Transmission electron microscope (TEM) revealed that CeO 2 NPs were quasi-spherical with sizes ranging from 10 to 40 nm. The most optimum concentration of siam orange peel extract was 10%. IC50 value of 70.55 mg mL -1 indicates a strong antioxidant activity of sample. Additionally, the antibacterial activity showed that CeO 2 NPs were highly effective against S.aureus bacteria demonstrating their potential for biomedical applications.
Integrated PLA/LLDPE nanocomposites with compatibilizer and hydroxyapatite-zinc oxide: Mechanical, physical, thermal, and morphological properties Ahmad Hafizullah Ritonga, Vivi Sisca, Barita Aritonang, Debi Meilani, Gusliani Eka Putri, Enzo Wiranta Battra Siahaan South African Journal of Chemical Engineering, 2025 • HAp-ZnO HNP was synthesized by mixing HAp and ZnO in ethanol and water, with the pH adjusted to 11 under acidic conditions using ammonium hydroxide. • HAp/ZnO HNP was integrated into the PLA/LLDPE matrix using the LO compatibilizer in an internal mixer under melt-phase conditions at 160°C. • The PLA/LLDPE/LO/HAp-ZnO nanocomposite significantly improved mechanical, physical, and thermal properties. • Enhanced compatibility and uniform nanoparticle dispersion within the PLA/LLDPE/LO matrix were observed after the integration of HAp-ZnO HNP. The integration of Polylactic Acid (PLA)/Linear Low-Density Polyethylene (LLDPE) nanocomposites with Hydroxyapatite-Zinc Oxide hybrid nanoparticles (HAp-ZnO HNPs) as fillers and LLDPE-grafted-Oleic Acid (LLDPE-g-OA) as a compatibilizer was successfully conducted. This study examines the improvement of mechanical, physical, thermal, and morphological properties of PLA/LLDPE blends through the incorporation of HAp-ZnO HNPs and LLDPE-g-OA (LO) to enhance their strength, durability, and biodegradability. The HAp-ZnO HNPs were synthesized by mixing HAp and ZnO in an ethanol-water solution (20:80), adjusting the pH to 11 with ammonium hydroxide, and then applying sonication, filtration, washing, and drying. The nanocomposites were prepared by blending PLA, LLDPE, LO, and 5.0 wt.% HAp-ZnO HNPs in an internal mixer at 160°C. The incorporation of HAp-ZnO HNPs improved tensile strength (9.171 MPa), elongation at break (52.863%), and Young's modulus (487.327 MPa) while reducing water absorption to 0.72%. HAp-ZnO HNPs also accelerated biodegradation, increasing weight loss from 0.73% at 15 days to 15.81% at 90 days. Thermal analysis showed enhanced thermal stability, a higher melting point, and faster degradation due to HAp-ZnO HNPs. FTIR spectra revealed complex interactions among the materials, and morphological analysis confirmed good compatibility with evenly nanoparticle dispersion. These findings indicate the potential of HAp-ZnO HNPs as effective fillers and co-compatibilizers for improving the overall properties of PLA/LLDPE blends.
The effect of adding palm shell ash on soil shear strength Debby Endriani, Nor Faizah Bawadi, Ahmad Hafizullah Ritonga Iop Conference Series Earth and Environmental Science, 2025 The soil in Tanjung Rejo Village, Percut Sei Tuan, Deli Serdang, is characterized by fine-grained clay with low stability. To enhance stability, this study focuses on soil stabilization using palm shell ash mixtures at varying percentages (0%, 4%, 6%, 8%, 10%, and 12%) under optimum moisture conditions. Stabilization involves mixing the clayey soil with additional materials to improve its technical properties, specifically employing palm kernel shell ash. Testing was conducted following ASTM methods. As the percentage of palm shell ash in the mixture increased, both cohesion and friction angle values showed an increasing trend, reaching optimal values at 10% palm shell ash. The Direct Shear test on native soil yielded the cohesion of 10.3 KPa and a shear angle of 14.6°, whereas the most optimum values for cohesion (14.1 KPa) and friction angle (24.60°) were observed in the soil mixture with 10% Palm Shell Ash (PSA). The palm shell ash mixture has good potential for use in road pavement, especially in Tanjung Rejo Village, Percut Sei Tuan, Deli Serdang, North Sumatra, Indonesia.
Catalytic Innovation for Renewable Energy: TiO2-Supported Precipitated Calcium Carbonate Catalyst for Eco-Friendly Biodiesel Synthesis Vivi Sisca, Syukri, Zilfa, Novesar Jamarun, Denny Akbar Tanjung, Ahmad Hafizullah Ritonga, Dicky Annas, Khoiriah Khoiriah, Poedji Loekitowati Hariani Baghdad Science Journal, 2025 إن الوقود الحيوي المنتج من خلال تفاعلات الاسترة مع محفزات قاعدية متجانسة وغير متجانسة هو مصدر طاقة بديل واعد. تستخدم هذه الدراسة كربونات الكالسيوم المترسبة (PCC) المخصبة بثاني أكسيد التيتانيوم لإنتاج الوقود الحيوي من زيت نباتي مستعمل. تم التعرف على المحفز المصنّع بشكل شامل من خلال تحليلات XRD وXRF وSEM وBET وFT-IR ثم تم تطبيقه في تفاعل الاسترة. أظهرت النتائج أن PCC المخصب بثاني أكسيد التيتانيوم هو محفز فعال، ينتج الوقود الحيوي بكفاءة 95.09٪ في ظل الظروف المثلى: محفز 5٪ بالوزن، ونسبة الميثانول إلى الزيت 6: 1، ودرجة حرارة التفاعل 65 درجة مئوية، ووقت التفاعل 4 ساعات. أدى تحسين الخصائص الحفزية، وزيادة مساحة السطح، وتعزيز المواقع الأساسية إلى تحسين إنتاج الوقود الحيوي بشكل كبير.
Bearing capacity of Percut Sei Tuan clay stabilized with palm shell ash Debby Endriani, Nor Faizah Bawadi, Aazoki Waruwu, Ahmad Hafizullah Ritonga Iop Conference Series Earth and Environmental Science, 2024 Improvements to the bearing capacity of the soil have been carried out and developed at this time, one of which is the stabilization of clay soils. There are several alternatives to solve low soil bearing capacity, one of which is using geo-synthetic materials but has a weakness in terms of high cost. Another alternative is to add palm shell ash as a stabilizing agent. The effect of adding palm shell ash has not been thoroughly studied, so further research is needed. The material added is palm shell ash with a variation of 0%, 4%, 8%, 10%, and 12% in each test. The tests carried out in the laboratory were water content (w), specific gravity test (Gs), Atterberg limit test, sieve analysis (sieve analysis), soil compaction test, and CBR (California Bearing Ratio) test. The CBR test was carried out by curing the soil for 1, 3, 5, and 7 days with a mixture of palm shell ash before compaction. The soil in this study belongs to the A-7-5 group. The CBR (California bearing ratio) value increased with the increase in the palm shell ash percentage in the mixture after curing the soil. The highest CBR value was in the variation of 12% palm shell ash with a 7-day curing period of 6.92% with a soil bearing capacity of 5.06.
The influence of addition palm shell ash to mineralogy and physical properties of clay soil Arpn Journal of Engineering and Applied Sciences, 2018
RECENT SCHOLAR PUBLICATIONS
Kimia Polimer Farmasi AH Ritonga PT. Bukuloka Literasi Bangsa , 2026 2026
The Influence of Activated Carbon Produced from Duck Eggshells as an Adsorbent for Free Fatty Acid Content of Used Cooking Oilc B Aritonang, AH Ritonga, K Harefa, H Herlina, DY Wiratma JURNAL FARMASIMED (JFM) 8 (2), 1018-1024 , 2026 2026
Anti-Inflammatory Potential of Combined Turmeric Rhizome Extract (Curcuma longa L.) and Hydroxyapatite in Male White Mice (Mus musculus) AH Ritonga, F Amelia, H Herlina, B Aritonang, K Harefa JURNAL FARMASIMED (JFM) 8 (2), 835-843 , 2026 2026
Efektivitas Antimikroba Kombinasi Ekstrak Etanol Rimpang Kunyit (Curcuma longa L.) dan Hidroksiapatit dalam Menghambat Pertumbuhan Streptococcus sobrinus AH Ritonga, KE Purba, B Aritonang, H Herlina, K Harefa Jurnal Indah Sains dan Klinis 7 (1), 1-8 , 2026 2026
The Role of Quality Management in Ensuring the Accuracy of Clinical Laboratory Test Result at Grandmed Lubuk Pakam Hospital S Ramadhani, AH Ritonga, B Lubis JURNAL KESMAS DAN GIZI (JKG) 8 (2), 1530-1537 , 2026 2026
Analysis of the Effectiveness of Quality Management through the Implementation of Quality Assurance (QA) and Quality Control (QC) in Improving Microbiology Laboratory … R Rahmawati, AH Ritonga, S Siregar JURNAL KESMAS DAN GIZI (JKG) 8 (2), 1544-1551 , 2026 2026
Laboratory Officer Compliance with Standard Operating Procedures at the Laboratory Installation of Grandmed Lubuk Pakam Hospital Based on the Quality of Laboratory Examination … A Prahesti, AH Ritonga, NBG Munthe JURNAL KESMAS DAN GIZI (JKG) 8 (2), 1538-1543 , 2026 2026
Buku Ajar Kimia Organik 1 AH Ritonga CV. Inovasi Publishing Indonesia 1, 1-305 , 2026 2026
Oleic acid-modified zinc oxide incorporated compatibilized PLA/LLDPE nanocomposites: Physical, mechanical, thermal, and morphological properties AH Ritonga, B Aritonang, D Meilani, H Herlina, V Sisca, GE Putri, ... South African Journal of Chemical Engineering 56 (April), 100869 , 2026 2026
Solvent-free steam extraction of Citrus nobilis Peel essential oil: Chemical composition and bioactivity GE Putri, S Arief, N Jaffar, P Dafriani, IY Darma, V Sisca, AH Ritonga, ... Results in Chemistry, 103141 , 2026 2026
Biosynthesis of Zinc Oxide Nanoparticles Using Noni Fruit Extract (Morinda citrifolia) for Indigo Carmine Photodegradation V Sisca, N Budhiandini, D Annas, A Rahayu, AH Ritonga Moroccan Journal of Chemistry 14 (1), 136-151 , 2026 2026 Citations: 5
Chemical Communication, Information, and Education (CIE) in Enhancing the Safety of School Snacks H Herlina, AH Ritonga, K Harefa, RS Sitorus, I Hafiz JURNAL PENGMAS KESTRA (JPK) 5 (2), 195-201 , 2025 2025
Development of Molecularly Imprinted Polymer Materials as Selective Recognition Elements for Electrochemical Meropenem Sensors H Herlina, AH Ritonga, A Febriady, A Rahayu, NG Sinaga JURNAL FARMASIMED (JFM) 8 (1), 265-274 , 2025 2025
The Effect of a Combination of Activated Carbon and Bentonite on Reducing COD, BOD, and TSS Levels in Tofu Industry Wastewater B Aritonang, AH Ritonga, K Harefa, DY Wiratama, H Herlina JURNAL FARMASIMED (JFM) 8 (1), 405-412 , 2025 2025
Application of Chemical Principles in the Preparation of Infused Water as an Educational Effort to Prevent Hyperglycemia at SMK Negeri Pantai Labu AH Ritonga, H Herlina, FR Harahap, RS Sitorus, K Harefa JURNAL PENGMAS KESTRA (JPK) 5 (1), 1-7 , 2025 2025
Enhancement of Asphalt Resilience through Functionalization of Natural Rubber with Glycidyl Methacrylate, Maleic Anhydride, and Divinylbenzene NR Wijaya, Tamrin, Eddiyanto, JA Laksmono, AH Ritonga International Journal of Technology 16 (3), 993-1003 , 2025 2025 Citations: 3
Relationship Between Implementation of Risk Analysis (Risk Assessment) and Reducing Patient Safety Incidents in Inpatient Installations AH Ritonga JURNAL KESMAS DAN GIZI (JKG) 7 (2), 493-501 , 2025 2025
Reduction of BOD, COD, and TSS in Textile Wastewater Using Bentonite Activated Charcoal Adsorbent B Aritonang, AH Ritonga, K Harefa Jurnal Farmasimed (JFM) 7 (2), 381-389 , 2025 2025 Citations: 5
Aktivitas Antibakteri Kombinasi Ekstrak Etanol Daun Mangga (Mangifera indica L.) dengan Hidroksiapatit dan Organo-Hidroksiapatit terhadap Staphylococcus aureus AH Ritonga, H Herlina, B Aritonang, SA Lestari, R Safitri Jurnal Dunia Farmasi 9 (2), 77-90 , 2025 2025
Hybrid polyol-based polyurethane from pine merkusii resin and polyethylene glycol 400 for sustainable asphalt modification Tamrin, S Lenny, M Misran, AH Ritonga, M Syaftiani South African Journal of Chemical Engineering 53 (July), 12-20 , 2025 2025
MOST CITED SCHOLAR PUBLICATIONS
Organic Modification of Precipitated Calcium Carbonate Nanoparticles as Filler in LLDPE/CNR Blends with the Presence of Coupling Agents: Impact Strength, Thermal, and Morphology AH Ritonga, N Jamarun, S Arief, H Aziz, DA Tanjung, B Isfa, V Sisca, ... Journal of Materials Research and Technology 17 (C), 2326-2332 , 2022 2022.0 Citations: 31
Aktivitas Antibakteri Ekstrak Etanol Kulit Markisa Ungu (Passiflora Edulis Sims) Terhadap Bakteri Propionibacterium Acnes K Harefa, B Aritonang, AH Ritonga Jurnal Multidisiplin Madani 2 (6), 2743-2758 , 2022 2022.0 Citations: 25
Green synthesis of cerium oxide nanoparticles using Citrus nobilis Lour. peel extract and evaluation of their potential as antibacterial and antioxidant agents GE Putri, A Labanni, S Arief, P Dafriani, IY Darma, S Handayani, N Jaffar, ... Case Studies in Chemical and Environmental Engineering 11 (June 2025), 101062 , 2024 2024.0 Citations: 24
Influence of LLDPE-g-MA on Mechanical Properties, Degradation Performance and Water Absorption of Thermoplastic Sago Starch Blends DA Tanjung, N Jamarun, S Arief, H Aziz, AH Ritonga, B Isfa Indonesian Journal of Chemistry 22 (1), 171-178 , 2022 2022.0 Citations: 23
The enhancement of mechanical, physical, and thermal properties of modified asphalt mixture with lignin from mahogany sawdust in the presence of diphenylmethane 4,4'-diisocyanate Tamrin, AH Ritonga, B Aritonang International Journal of Adhesion and Adhesives 125, 103431 , 2023 2023.0 Citations: 19
Improvement of Mechanical, Thermal, and Morphological Properties of Organo-Precipitated Calcium Carbonate Filled LLDPE/Cyclic Natural Rubber Composites AH Ritonga, N Jamarun, S Arief, H Aziz, DA Tanjung, B Isfa Indonesian Journal of Chemistry 22 (1), 233-241 , 2022 2022.0 Citations: 19
Pembuatan Sabun Padat Antiseptik Ekstrak Etanol Kulit Jeruk Lemon (Citrus limon (L.) Burm. f.) EM Sinaga, B Aritonang, NF Ambarwati, AH Ritonga Jurnal Indah Sains dan Klinis 2 (3), 17-24 , 2021 2021.0 Citations: 19
Counseling on the Use of Infused Water for Body Health in Junior High School Amal Luhur Medan AH Ritonga, B Aritonang, K Harefa, RS Sitorus, Herlina, D Meilani Jurnal Pengmas Kestra (JPK) 2 (2), 184-190 , 2022 2022.0 Citations: 12
Modifikasi Aspal Polimer Memanfaatkan Karet Ban Bekas Menggunakan Divenil Benzena dan Dikumil Peroksida Melalui Proses Ekstruksi AH Ritonga Jurnal Kimia Saintek dan Pendidikan 1 (1), 8-13 , 2017 2017.0 Citations: 10
Purification of used Cooking Oil using a Combination of Activated Carbon and Bentonite Adsorbents B Aritonang, AH Ritonga, K Harefa, DY Wiratma, H Herlina Jurnal Farmasimed (JFM) 7 (1), 31-40 , 2024 2024.0 Citations: 9
Biokimia Kesehatan GE Putri, BD Putri, AH Ritonga, Gusfiyesi, Futeri, Renny CV. Mega Press Nusantara , 2023 2023.0 Citations: 9
Biosorption of Hexavalent Chromium Cr (VI) using Microalgae Scenedesmus sp as Environmental Bioindicator R Kartika, AH Ritonga, L Sulastri, S Nurliana, D Irawan, P Simanjuntak International Journal of Technology 14 (4), 791-799 , 2023 2023.0 Citations: 9
The Influence of Oleic Acid and Benzoyl Peroxide Against Oleic Acid Grafted onto LLDPE AH Ritonga, N Jamarun, S Arief, H Aziz, DA Tanjung, B Isfa Rasayan Journal of Chemistry 15 (1), 190-196 , 2022 2022.0 Citations: 9
Pembuatan Aspal Polimer Menggunakan Karet SIR-20 Yang Diinisiasi Oleh Adanya Dikumil Peroksida Melalui Proses Ekstrusi AH Ritonga Jurnal STIKNA 1 (2), 123-130 , 2017 2017.0 Citations: 9
Karakterisasi Aspal Polimer Dari Limbah Polistirena dan Serbuk Karet Ban Bekas Menggunakan Divenil Benzena dan Inisiator Dikumil Peroksida AH Ritonga Akademia 21 (2), 7-14 , 2017 2017.0 Citations: 9
H.(2022). Antibacterial Activity of Ethanol Extract of Purple Passion Fruit Peel (Passiflora Edulis Sims) on Propionibacterium Acnes Bacterial K Harefa, B Aritonang, A Ritonga Jurnal Multidisiplin Madani 2 (6), 2743-2758 , 0 Citations: 9
The impact of butterfly pea flower (Clitoria ternatea L.) extract on atherosclerosis biomarker profiles in obese white rats (Rattus norvegicus L.) K Harefa, AH Ritonga, B Aritonang, R Gurusinga, S Wulan, I Irmayani Journal of Biomedicine and Translational Research 10 (1), 7-14 , 2024 2024.0 Citations: 8
Effects of LLDPE on Mechanical Properties, Degradation Performance, and Water Absorption of Thermoplastic Sago Starch Blends DA Tanjung, N Jamarun, S Arief, H Aziz, B Isfa, AH Ritonga, V Sisca International Journal of Technology 14 (1), 173-184 , 2023 2023.0 Citations: 8
Improving Mechanical and Physical Properties on Thermoplastic Sago Starch Blends with the Addition of Polypropylene DA Tanjung, N Jamarun, S Arief, H Aziz, AH Ritonga, B Isfa Rasayan Journal of Chemistry 14 (4), 2451-2458 , 2021 2021.0 Citations: 8
Pemanfaatan limbah sekam padi sebagai bahan dasar pembuatan briket arang AH Ritonga, DA Tanjung Pelita Masyarakat 1 (1), 39-45 , 2019 2019.0 Citations: 8
