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Riza Mahendra
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Earth & Planetary Sciences Education Environmental Science Social Sciences Other

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Pengembangan E-LKPD Berintegrasi Microscale Lab menggunakan Budaya Mamaq pada Materi Asam Basa Kelas XI Mahendra, Riza; Junaidi, Eka; Arian Sani Anwar, Yunita
Chemistry Education Practice Vol. 8 No. 1 (2025): Edisi Mei
Publisher : FKIP University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/cep.v8i1.7910

Abstract

This research aims to develop chemistry learning media by integrating a small-scale laboratory (microscale lab) using the mamaq culture approach to improve students' conceptual understanding of acid-base material. This research is a development research with a 4D model design (Define, Design, Develop, Disseminate). The media developed is a Student Worksheet in electronic form (E-LKPD) which is uploaded to the website, making it easy to access and allowing the addition of images and learning videos related to acid-base material by associating it with mamaq culture. In addition, this E-LKPD also contains quizzes, sample questions, and evaluations to measure students' understanding of the material studied. This LKPD was developed using an experimental approach, integrated with a small-scale laboratory that allows practicum outside the lab with smaller tools and materials without reducing the essence of the practicum. This medium has been validated by two validators using a validation questionnaire, and the data was analyzed with an average formula, resulting in a score of 3.32 in the very valid category. Furthermore, a trial was carried out to assess the practicality of this media, by collecting responses from teachers and students. The results of the practical test showed a score of 91% from teachers and 85% from students, both in the very valid category.
Efektivitas Perlindungan Sinar UV Ekstrak Daun Katuk (Sauropus Androgynus (L. Merr)) Berdasarkan Nilai Sun Protection Factor (SPF) Fathiyyah, Alifka Jinan; Sakinatut Tamimi; Riza Mahendra; Afra Amaniah; Gina Harnum Fatin; I Nyoman Loka
Contextual Natural Science Education Journal Vol. 2 No. 1 (2024): January - March 2024
Publisher : Science Education Doctoral Study Program, Postgraduate, Mataram University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/cnsej.v2i1.564

Abstract

Besarnya kemampuan tabir surya ditentukan melalui nilai SPF yang menyatakan lamanya kulit seseorang berada dibawah sinar matahari tanpa mengalami sengatan surya. Penelitian ini bertujuan untuk memperkirakan nilai SPF dari ekstrak etanol, fraksi n-heksan, fraksi etil asetat dan fraksi air rimpang lengkuas (Alpinia galanga). Ekstrak daun katuk memiliki kandungan metil sinamat yang dapat berkhasiat sebagai tabir surya. Penelitian dilakukan secara in vitro menggunakan metode Spektrofotometri UV-Vis. Absorbansi ekstrak dan fraksi etil asetat diukur pada panjang gelombang sinar UV-B yaitu 290-320 nm. Penentuan nilai SPF didasarkan pada persamaan Mansur. Hasil pengujian menunjukkan bahwa ekstrak etanol dan fraksi air. diperoleh nilai SPF dari ketiga sampel yakni masing-masing sebesar 18,39 untuk yang sampel daun katuk, kemudian fraksi etil asetat sebesar 7,40, dan ekstrak etanol sebesar 9,79. Hasil analisis data menunjukkan adanya perbedaan signifikan antara ekstrak etanol ekstrak daun katuk. dengan fraksi n-heksan, fraksi etil asetat dan fraksi air. Pada penelitian ini dapat disimpulkan bahwa fraksi etil asetat daun katuk. galanga memiliki nilai SPF paling tinggi sehingga berpotensi sebagai tabir surya terhadap proteksi sinar UV-B.
Co-Authors Afra Amaniah Arian Sani Anwar, Yunita Eka Junaidi Fathiyyah, Alifka Jinan Gina Harnum Fatin I Nyoman loka Sakinatut Tamimi