Faculty of Mathematics and Natural Sciences: Recent submissions
Now showing items 61-80 of 11098
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Uji Aktivitas Antioksidan Dan Isolasi Ekstrak Etil Asetat Daun Jambu Biji Kristal (Psidium guajava L.) Serta Pemanfaatannya Sebagai Sunscreen
(Universitas Sumatera Utara, 2025)Crystal guava plant (P. guajava L.) is one of the species of the Myrtaceae family that has potential allelopathic properties. This study aims to test the antioxidant bioactivity, determine the SPF value of sunscreen ... -
Aplikasi Entomologi Forensik Menggunakan Serangga Air Untuk Menganalisis Kualitas Air Sungai Sebagai Upaya Peningkatan Kesehatan Ekosistem Sungai Dari Cemaran Logam
(Universitas Sumatera Utara, 2025)Forensic Entomology is a science that utilizes insects in identification. Metals are often found in river water polluted by industrial processes. To separate metals from river water, blood clam shells (Anadara granosa) ... -
Adsorpsi Logam Pb pada Adsorbent Berbasis Karboksimetil Selulosa dan Hidroksipropil Metil Selulosa dengan Divinil Sulfon sebagai Agen Ikat Silang
(Universitas Sumatera Utara, 2025)This study examines the adsorption process of Pb metal on adsorbents based on carboxymethyl cellulose (CMC) and hydroxypropyl methyl cellulose (HPMC) with divinyl sulfone (DVS) as a crosslinking agent. The adsorbent was ... -
Penurunan Kadar Logam Besi (Fe) Menggunakan Karbon Aktif dari Tongkol Jagung (Zea Mays) sebagai Adsorben dengan Variasi Aktivator Asam Fosfat (H3PO4)
(Universitas Sumatera Utara, 2025)Activated carbon is an amorphous compound produced from materials containing carbon. One of the materials that can be used to make activated carbon is corn cob husks which are still underutilized. This research was conducted ... -
Kemampuan Bakteri Endofit Tumbuhan Mangrove Avicennia marina dalam Menghambat Serangan Penyakit Layu Fusarium pada Tanaman Cabai
(Universitas Sumatera Utara, 2025)Mangroves are known to have special abilities to adapt and grow in extreme environmental conditions. Mangroves have been reported to harbor endophytic bacteria that have potential as biological control agents. Additionally, ... -
Kajian Pemberian Limbah Cair Pabrik Kelapa Sawit pada Areal Tanaman Buah Naga terhadap Keanekaragaman Makrofauna Tanah
(Universitas Sumatera Utara, 2025)The application of palm oil mill effluent (POME) on dragon fruit plant areas as fertilizer with variations in the application time will affect the presence and diversity of soil macrofauna, which in turn can reflect the ... -
Penggunaan Nanopartikel Kitosan untuk Enkapsulasi Penghantaran Bahan Aktif pada Sediaan Facial Cleansing
(Universitas Sumatera Utara, 2025)The development of natural science has given birth to various products in the world of cosmetics, for example facial cleansing. Facial cleansing is a beauty product made from surfactants and active ingredients to cleanse ... -
Pengaruh Variasi Massa Kalium Bromida (KBR) terhadap Sintesis pada Nanosilikon dari Pasir Alam Pantai Cermin secara Magnesiotermik
(Universitas Sumatera Utara, 2021)Synthesis of nanosilicon from natural sand has been carried out with the addition of KBr salt by magnesiothermic method. Silica was extracted from natural sand with the addition of 10 N NaOH and 6 N HCl and analyzed by ... -
Pemanfaatan Ekstrak Etanol Mahkota Nanas (Ananas Comosus L. Merr.) sebagai Antioksidan pada Sediaan Moisturizing Gel
(Universitas Sumatera Utara, 2025)Moisturizing gel is one of the treatments that aims to improve dry skin with ingredients contained in cosmetics. Pineapple crown (Ananas comosus L. Merr) is known to contain flavonoid compounds that have the potential to ... -
Pemanfaatan Zeolit Sintesis dari Limbah Fly Ash Sebagai Adsorben Logam Mangan (Mn) pada Air Sumur Bor di Kawasan Deli Tua
(Universitas Sumatera Utara, 2025)Fly ash waste is a waste that has not received optimal treatment in its utilization until now. Fly Ash has a high Silica (Si) and Aluminum (Al) content so it is suitable to be used as a synthetic zeolite that has an ... -
Formulasi Sediaan Krim Tabir Surya dari Karboksimetil Kitosan dan Penentuan Nilai SPF (Sun Protecting Factor) secara In Vitro
(Universitas Sumatera Utara, 2025)A study has been conducted on the use of carboxymethyl chitosan (KMK) in the formulation of sunscreen cream preparations as a skin protector from excessive sunlight. Sunscreen is a cosmetic ingredient that scatters UV ... -
Sintesis dan Karakterisasi Reduced Graphene Oxide (RGO) Terdoping Nanopartikel Besi Oksida (Fe2O3) sebagai Eletroda Baterai Primer
(Universitas Sumatera Utara, 2025)A study has been conducted on the Synthesis and Characterization of Reduced Graphene Oxide (RGO) Doped with Iron Oxide (Fe2O3) Nanoparticles as Primary Battery Electrodes. The purpose of this study was to analyze the ... -
Pembuatan Filter Berbasis Karbon Sekam Padi dan Zeolit Sintesis sebagai Pereduksi Ion Logam Pb dan Mn pada Air Sumur
(Universitas Sumatera Utara, 2025)In this study, a filter based on carbon from rice husk and synthetic zeolite was made for well water. First the rice husk is pulverized and then carbonized with temperature variations of 700oC, 800oC, and 900oC. Then the ... -
Sistem Pengukuran Kecepatan Arus dan Ketinggian Permukaan Air Sungai Bilah Rantauprapat Secara Digital Berbasis Internet of Things (IoT)
(Universitas Sumatera Utara, 2025)The high intensity of rainfall in the upstream area of the Bilah Rantauprapat River significantly increases the water discharge, potentially triggering flooding in the downstream area. This study aims to develop a real-time ... -
Sistem Pengereman Adaptif Turbin Angin Menggunakan Servo Dilengkapi dengan Monitoring Berbasis Internet of Things (IoT)
(Universitas Sumatera Utara, 2025)Wind turbines are increasingly recognized as one of the effective solutions for generating clean and sustainable energy. In this study, an adaptive braking system for five-bladed wind turbines was developed, utilizing the ... -
Sintesis Karbon Dots (CDs) Emisi Ganda Menggunakan Metode Hidrotermal dengan Penambahan Etilendiamin Sebagai Agen Pasivasi
(Universitas Sumatera Utara, 2025)Carbon dots are carbon nanoparticles with sp2/sp3 hybridization structures that exhibit single or dual emission during fluorescence phenomena. Dual-emission carbon dots offer advantageous excitation-emission characteristics ... -
Pemanfaatan Karbon Aktif dari Ampas Tahu dengan Aktivator Natrium Klorida (Nacl) dalam Penurunan Konsentrasi Logam Kadmium (Cd)
(Universitas Sumatera Utara, 2024)The waste produced by tofu dregs contains cellulose compounds which can be used as a basic ingredient in making active carbon. The aim of this research is to determine how to make active carbon by utilizing tofu dregs ... -
Potensi Enterobacter Sp. LB04, Bacillus Cereus LB13, dan Pseudomonas Sp. LB14 Sebagai Agen Biofungisida Cendawan Penyebab Kerusakan Buah Tomat
(Universitas Sumatera Utara, 2024)Postharvest fruit rot in tomatoes due to pathogenic field fungi are estimated to cause between 25 and 42% economic losses of total production globally. The primary utilization of synthetic fungicides to control postharvest ... -
Penerapan Metode Double Exponential Smoothing untuk Meramalkan Jumlah Angkatan Kerja di Kabupaten Toba Samosir Pada Tahun 2021-2022
(Universitas Sumatera Utara, 2021)The workforce is a population aged 15 to 65 years who are currently working or looking for work. The workforce in Toba Samosir Regency has increased almost every year. The data in this study are secondary data obtained ... -
Aplikasi Penalized Maximum Likelihood Estimation pada Distribusi Weibull dengan Algoritma Gradient Descent
(Universitas Sumatera Utara, 2025)The Weibull distribution is widely used in reliability analysis and failure modeling due to its flexibility in modeling various types of data. For accurate parameter estimation, the Penalized Maximum Likelihood Estimation ...