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PENGEMBANGAN MEDIA PEMBELAJARAN BERBASIS ISPRING PRESENTER UNTUK MENIGKATKAN HASIL BELAJAR SISWA PADA MATERI MINYAK BUMI Siti Khodijah Dalimunthe; Destria Roza
PROSIDING SEMINAR KIMIA 2021: SEMINAR NASIONAL KIMIA 2021
Publisher : PROSIDING SEMINAR KIMIA

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

Abstract

Penelitian ini bertujuan untuk menghasilkan media pembelajaran berbasis iSpring Presenter yang layak digunakan pada materi minyak bumi. Dan kedua adalah untuk mengetahui apakah hasil belajar siswa yang menggunakan iSpring Presenter lebih tinggi dari hasil belajar siswa yang tidak menggunakan media pembelajaran berbasis iSpring Presenter atau hanya memakai media powerpoint biasa saja. Metode penelitian yang digunakan pada penelitian ini adalah penelitian dan pengembangan atau Research and Development (R&D). Teknik pengambilan sampel adalah purposive sampling. Dari enam kelas diperoleh kelas XI IPA 1 sebagai kelas eksperimen dengan meggunakan media iSpring Presenter dan kelas XI IPA 3 sebagai kelas kontrol menggunakan media powerpoint biasa. Analisis data dalam penelitian ini menggunakan uji t satu pihak, yaitu menggunakan uji pihak kanan pada taraf signifikan 5%. Hasil penelitian menunjukkan bahwa media pembelajaran iSpring Presenter yang dikembangkan memperoleh kelayakan materi dan media dengan hasil beturut sebesar 89% dan 85,6% dengan kategori sangat layak untuk digunakan. Kemudian hasil belajar siswa diperoleh data harga thitung > ttabel (3,90 > 1,670), dapat disimpulkan bahwa hasil belajar siswa menggunakan media pembelajaran berbasis iSpring presenter lebih tinggi dibandingkan hasil belajar siswa menggunakan media pembelajaran powerpoint biasa. Kata kunci : Kelayakan Media, Hasil Belajar, iSpring Presenter, PowerPoint.
Antibacterial Activity of Extract A. luteocarpa Tita Juwitaningsih; Destria Roza; Nora Susanti
Indonesian Journal of Chemical Science and Technology (IJCST) Vol 1, No 1 (2018): Juli 2018
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v1i1.10182

Abstract

Meat is one of the food products that can easily be damaged, ( therefore it is necessary to preserve the process). therefore it needs to be done the process of preservation. In this study we studied the anti-bacterial activity of Alpinia luteocarpa extract against fresh meat rot bacteria, with paper disc diffusion method which is the standard recommended by the Clinical and Laboratory Standard Institute (CLSI,2012). The results of antibacterial activity test showed extract and fraction of A. luteocarpa able to inhibit bacterial growth B.cereus ATCC 21772   and. K.  pneumonia ATTC 13773. The bacteriostatic properties of the extract and fraction of A. luteocarpa against B. cereus ATCC 21772 and K. pneumonia ATTC 13773 were better than the positive control of chlorhexidine antibiotics (500 μg / mL) with inhibition zones 9-11 mm and 7-9 mm.
Study of Phytochemicals, Toxicity, Antibacterial Activity of Ethyl Acetate Leaf Extract Extract (Paperomiapellucida L) Ida Duma Riris; Tita Juwitaningsih; Destria Roza; Marini Damanik; Albinus Silalahi
Indonesian Journal of Chemical Science and Technology (IJCST) Vol 3, No 2 (2020): July 2020
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v3i2.19532

Abstract

Suruhan Leaf (Paperomiapellucida L) is a weedy plant that is used by rural communities as herbal medicine. In this study, phytochemical tests have identified compounds contained in the ethyl acetate extract, then the toxicity test was carried out by the Brint Shrimp LethallytyTocycity (BSLT) method using Artemia Salina Leach shrimp larvae, an antibacterial activity test for bacteria: Bacillus cereus (ATCC) 11778), S. aureus (ATCC 25923), E. coli (ATCC 25922), S. saprophytic (ATCC 49907), Catsobacterfrendi (ATCC 18090), P.acne (ATCC 27853), Epidermis (ATCC 12228) with diffusion methods, various of concentration 1; 5; 10; 25% as control used chloramphenicol 30 mcg, the highest inhibitory zone at a concentration of 25% showed a strong antibacterial succession of 20.7; 11.1; 29.7; 15; 13.5; 10; 17.3 mm. The results of the identification of compounds in ethyl acetate extract are alkaloids, flavonoids, steroids, saponins, and tannins. The toxicity of LC50 is 71.28 ppm (toxic).
PENGEMBANGAN MODUL LAJU REAKSI BERBASIS PEDAGOGICAL CONTENT KNOWLEDGE (PCK) UNTUK MENINGKATKAN HASIL BELAJAR SISWA Frisca Zahrona Utami Harahap; Destria Roza
Jurnal Inovasi Pembelajaran Kimia (Journal Of Innovation in Chemistry Education) Vol 2, No 1 (2020): APRIL 2020
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (325.91 KB) | DOI: 10.24114/jipk.v2i1.17853

Abstract

This study aims to analyze the feasibility of the PCK Chemistry module and learning outcomes on the subject matter of the reaction rate taught by the PCK Chemistry module class XI MAN 1 Medan Medan. The selected sample is class XI MIA 3 as an experimental class. The method used in this research is R&D. The module analysis results state that the average overall validation result is 3.65 which means that the module is feasible to use. While the results of the module analysis based on the respondents obtained an average of 3.70 which means that the developed PCK module is appropriate to use. This is also evidenced from student learning outcomes that are taught using the PCK chemistry module. Hypothesis testing is done by using the t-one party test that is the right side, with the results of this study at a significance level of 5% (α = 0.05) indicating that tcount> t table (12.63> 1.68) then Ho is rejected. Thus, showing chemistry learning outcomes using the PCK chemistry module is greater or equal to KKM, where an average pretest of  28.25 is obtained and an average of posttest is obtained an average of 86.04.
Pengaruh Inkuiri Terbimbing Berbasis PCK Terhadap Hasil Belajar Kimia dan Aktivitas Siswa Mawaddah Rahmi; Destria Roza
Jurnal Inovasi Pembelajaran Kimia (Journal Of Innovation in Chemistry Education) Vol 1, No 1 (2019): APRIL 2019
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (145.035 KB) | DOI: 10.24114/jipk.v1i1.12532

Abstract

Penelitian ini dilakukan untuk mengetahui pengaruh inkuiri terbimbing berbasis pedagogical content knowledge (PCK) terhadap hasil belajar kimia siswa kelas XI MAN 1 Stabat pada materi koloid. Instrumen yang digunakan yaitu tes objektif dalam bentuk pilihan ganda berjumlah 20 soal. Kelas eksperimen diberi perlakuan dengan menggunakan model inkuiri terbimbing berbasis PCK dan kelas kontrol diberi perlakuan dengan menggunakan model pembelajaran konvensional. Dari hasil penelitian, untuk kelas eksperimen diperoleh nilai rata-rata postest adalah 84,5. Sedangkan nilai rata-rata postest kelas kontrol adalah 70,5. Data hasil kelompok sampel berdistribusi normal dan homogen. Hasil uji t dua pihak diperoleh thitung= 5,470 dan ttabel = 1,645, sehingga thitung > ttabel yang berarti Ha diterima dan Ho ditolak. Penilaian aktivitas siswa pada kelas eksperimen mendapat rata-rata sebesar 71,481dan kelas kontrol 62,962. Hasil uji t dua pihak diperoleh thitung= 3,101 dan ttabel = 1,645, sehingga thitung > ttabel yang berarti Ha diterima dan Ho ditolak. Berdasarkan hasil penelitian ini, maka dapat disimpulkan bahwa ada pengaruh model inkuiri terbimbing berbasis PCK terhadap hasil belajar kimia dan aktivitas siswa pada materi koloid kelas XI MAN 1 Stabat.
Isolation of secondary metabolite compounds of Coffee Benalu leaves (Loranthus parasiticus (L.) Merr.) and its antibacterial activity test Destria Roza; Nova Betria Sinaga; Christesya Ambarita
Jurnal Pendidikan Kimia (JPKim) Vol 14, No 2 (2022): August
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (308.581 KB) | DOI: 10.24114/jpkim.v14i2.33706

Abstract

Coffee parasite leaves (Loranthus parasiticus (L.) Merr) is one of the plants that can be used as a medicinal material commonly obtained in various subtropical regions or tropical regions. This study aims to isolation of secondary metabolite compounds from methanol extract of coffee leaves and antibacterial activity by of disc diffusion and microdilution methods against S. aureus bacteria, S. mutans, and S. viridians. The result of antibacterial activity against S. aureus bacteria, S. mutans, and S. viridians respectively is 7.5 mm; 7.9 mm; and 8 mm which indicates that the ability to inhibit the growth of methanol extract bacteria 1% coffee leaves belongs to the medium category. The results of the microdilution method in determining the value of KHM against bacteria S. Aureus, S. Mutans, and S. Viridians are equal to the KHM value of 5000 μg/mL. Meanwhile, the MBC value for S. aureus was >5000 g/Ml, for S. mutans was >5000 g/mL and for S. viridians it was 5000 g/mL, indicating that the methanol extract of the coffee parasite leaves was only an inhibitor. Isolation of secondary metabolite compounds is carried out by fractionation using Liquid Vacuum Chromatography and Gravitational Column Chromatography which are further characterized using the GC-MS instrument. The results of the isolation of secondary metabolites from the methanol extract of the leaves of the coffee parasite (Loranthus parasiticus (L.) Merr.) showed that the leaves of the coffee parasite contained any 9 compounds.Keywords:Antibacterial, Diethyltoluamide, Isolation, Loranthus parasiticus (L.) Merr.
THE LEVEL UNDERSTANDING OF THERMODYNAMIC CONCEPT FOR PHYSICS AND CHEMISTRY UNDERGRADUATE STUDENTS Dewi Wulandari; Destria Roza; M Aswin Rangkuti; Yul Ifda Tanjung; Irham Ramadhani
Jurnal Pendidikan Fisika Vol 12, No 1 (2023)
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/jpf.v12i1.42330

Abstract

Thermodynamics is an abstract concept making it difficult for physics and chemistry undergraduate student to understand it. The purpose of this research is to know the level understanding of the fundamental concepts of thermodynamics so that lecturers can develop strategies to teach thermodynamics appropriately. An exploratory small-scale study was conducted on students majoring in physics and chemistry to evaluate an understanding of heat, temperature, energy, work, thermodynamic processes and the first law of thermodynamics. The research sample consisted of 20 undergraduate students who were randomly selected from two majors, namely physics and chemistry. Data were collected through a diagnostic test to determine the level understanding of students' concepts which consisted of 20 questions. In addition, interviews were conducted with those of 20 students related to given questions. The results showed that the level of students' conceptual understanding of the concept of thermodynamics was still low. The main reasons that cause students have problems in understanding thermodynamic concepts are the concept of thermodynamics is an abstract physics concept and the matters of thermodynamics are lack in explanation and interpretation of phenomena and not linking them to daily life
Synthesis of silver nanoparticles from coffee parasite leaf extract (Scurrulla ferruginea (Roxb. ex Jack) Danser) and potential activity as an antioxidant and anticancer Destria Roza; Tico Guinessha Samosir; Sri Adelila Sari; Rini Selly
Jurnal Pendidikan Kimia Vol. 16 No. 1 (2024): April
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/jpkim.v16i1.54145

Abstract

This study aim is to know the results of the synthesis of silver nanoparticles from quercetin and Scurrula ferruginea (Roxb. Ex Jack) danser as well as its potential as an antioxidant and anticancer. The solvent used in the maceration extraction method in this research is the polar solvent methanol. Isolation and purification of thick extract compounds from coffee parasite leaves were carried out using liquid vacuum chromatography (CVC) and gravity column chromatography (GCC) methods. Silver (Ag) nanoparticle is made with the stirrer method at a speed of 1500 rpm for 60 minutes at a temperature of 70o C. Silver nanoparticle solution was produced and then characterized using FTIR (Fourier Transform Infra Red) and PSA (Particles Size Analyzer). PSA results analysis using extract coffee parasite size 214 nm particles, whereas using flavonoid isolate quercetin confirmed size 29 nm. FTIR showed that there was a stretching vibration of the OH group at a wave number of 3229.25 cm-1, the C=O function at the wave number 1637.87 cm-1, and the CO functional group at the wave number 1016.31 cm-1. Antioxidant test using the DPPH method was carried out in silver nanoparticle solution using extract Scurrula ferruginea (Roxb. Ex Jack) danser and with quercetin obtained an IC50 value of around 115.4 and 114.9 this result describes as moderate level of antioxidants. Even though the nanoparticle anticancer test was very weak, overall, the synthesis of silver nanoparticles using flavonoid isolates was better than using extracts from coffee parasite leaves.
8. Phytochemical Screening and Antibacterial Activity, Antilarvacides and Toxicity Test of Acetone Extract Pulutan Leave (Urena lobata) Siska Juita Gea; Tita Juwitaningsih; Ida Dumariris; Murniaty Simorangkir; Destria Roza
Jurnal Medika Veterinaria Vol 15, No 1 (2021): J.Med.Vet
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21157/j.med.vet..v15i1.21846

Abstract

This study aims to determine the content of secondary metabolites, antibacterial activity, antilarvicides, and pulutan leaf acetone extract toxicity test. Photochemical tests were carried out using several suitable reagents. Bacterial activity test using disc diffusion and microdilution methods against Salmonella typhi and Streptococcus mutans bacteria, then toxicity test using the BSLT method. Larvicide test by observing the mortality of Aedes aegypti larvae for 24 hours. Based on the phytochemical tests, pulutan leaves contain flavonoids, alkaloids, steroids, saponins, and tannins. The results of the antibacterial activity test showed activity against S. typhi and S. mutans with inhibition zone diameters of 7.05 mm and 8.25 mm, respectively. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values against S. typhi and S. mutans were 5000 g/mL and 5000 g/mL, respectively. The toxicity test results of pulutan leaf acetone extract had an LC50 value of 37.20 ppm, while the results of the larvicidal activity test had an LC50 value of 1971.19 ppm. The toxicity test results showed that the acetone extract of pulutan leaves was toxic and not anti-larvicidal to A. aegypti larvae. The bioactivity ability of pulutan leaf acetone extract is influenced by the content of flavonoids, alkaloids, steroids, saponins, and tannins. It can be concluded that the pulutan leaf extract in the Nias area has the potential as a source of antibacterial compounds
Modifikasi Media Pembelajaran Berbasis Android Pada Materi Laju Reaksi Untuk Meningkatkan Hasil Belajar Siswa Kelas XI SMA Astrika Sari Sinaga; Destria Roza
Educenter : Jurnal Ilmiah Pendidikan Vol. 1 No. 2 (2022): Educenter : Jurnal Ilmiah Pendidikan
Publisher : ARKA INSTITUTE

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55904/educenter.v1i2.43

Abstract

Penelitian ini bertujuan untuk mengetahui media pembelajaran berbasis android yang dimodifikasi pada materi laju reaksi telah sesuai dengan standar kelayakan BSNP, dan mengetahui hasil belajar siswa yang menggunakan media pembelajaran berbasis android pada materi laju reaksi lebih tinggi dari nilai KKM. Penelitian ini merupakan penelitian pengembangan dengan menggunakan model 4D (Define, Design, Develop, dan Disseminate) yang menghasilkan suatu produk yang dimodifikasi. Sampel dalam penelitian ini adalah siswa kelas XI IPA 3 yang diperoleh menggunakan teknik purposive sampling. Instrumen penelitian terdiri dari angket validasi media dan tes kognitif siswa. Data kelayakan media dianalisis secara deskriptif kualitatif dan data hasil belajar dianalisis secara statistik. Modifikasi yang dimaksud disini yakni memodifikasi media pembelajaran berbasis android menjadi lebih menarik dengan menambahkan animasi untuk memvisualkan materi teori tumbukan dan faktor-faktor yang mempengaruhi laju reaksi. Hasil penelitian menunjukkan bahwa media pembelajaran berbasis android yang dimodifikasi pada materi laju reaksi dinyatakan sangat layak dengan nilai rata-rata ahli materi 3,80; ahli media 3,64; dan praktisi pembelajaran 3,73. Hasil uji coba media menunjukkan bahwa rata-rata hasil belajar siswa setelah menggunakan media pembelajaran berbasis android lebih tinggi dari nilai KKM yakni 87,65 dan mengalami peningkatan sebesar 0,80 dengan kategori tinggi.