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Aktivitas Antibakteri Komposit Ag – Tulang Ikan Cakalang pada Staphylococcus aureus Pandelaki, Elmi C.J.; wuntu, Audy D.; Aritonang, Henry F.
Jurnal MIPA Vol 7, No 2 (2018)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jm.7.2.2018.21436

Abstract

Telah dilakukan penelitian untuk mengetahui aktivitas antibakteri komposit Ag – tulang ikan cakalang pada Staphylococcus aureus. Tulang ikan cakalang dikeringkan, dihaluskan dan diayak 65 mesh kemudian dicampur dengan larutan perak nitrat dengan perbandingan Ag : tulang ikan sebesar 5:1 , 4:2, dan 3:3  selama 1 jam pada suhu 70 ℃. Campuran kemudian di kalsinasi pada suhu 650 ℃ selama 2 jam. Uji aktivitas antibakteri dari komposit yang terbentuk dikerjakan dengan metode sumuran menggunakan bakteri Staphylococcus aureus. Hasil penelitian menunjukkan aktivitas antibakteri pada perbandingan 4:2 dengan lama waktu pencampuran 1 jam paling efektif untuk menghambat bakteri Staphylococcus aureus dengan diameter zona hambat sebesar 25 mm. Penelitian ini menunjukkan valorisasi dari produk sampingan industri makanan seperti tulang ikan untuk membentuk bahan yang berpotensi berharga sebagai bahan implan tulang yang resistan terhadap infeksi bakteriResearch has been conducted to determine the antibacterial activity of Ag - Bone skipjack tuna toward Staphylococcus aureus. Skipjack tuna bone dried, mashed and sifted 65 mesh then mixed with silver nitrate solution with a ratio of Ag : fish bones of 5:1, 4:2, and 3:3 for 1 hour at 70 ℃. The mixture was then calcined at 650 ℃ for 2 hours. Antibacterial activity test of the composites formed was done by the method of wells using the bacteria Staphylococcus aureus. The results showed that antibacterial activity at a ratio of 4: 2 with a one-hour mixing time was most effective for inhibiting Staphylococcus aureus bacteria with a 25 mm inhibition zone diameter. This study shows the valorization of food industry byproducts such as fish bones to form potentially valuable ingredients for bone implants resistant to bacterial infections
SINTESIS KOMPOSIT KITOSAN/MgO/Ag DAN ANALISIS EFEKTIVITASNYA SEBAGAI ANTIBAKTERI Maryani, Shintya; Aritonang, Henry F; Kamu, Vanda S
CHEMISTRY PROGRESS Vol 14, No 1 (2021)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/cp.14.1.2021.34291

Abstract

Penelitian tentang sintesis komposit kitosan/MgO/Ag dengan variasi massa prekursor AgNO3 0,05 g, 0,1 g, 0,15 g dan 0,2 g disintesis dengan metode kopresipitasi. Komposit yang dihasilkan dikarakterisasi menggunakan X-Ray Diffractometry (XRD) dan Scanning Electron Microscope (SEM). Selanjutnya, keefektifan komposit ini sebagai antibakteri diuji yaitu Staphylococcus aureus (Gram positif) dan Escherichia coli (Gram negatif). Hasil penelitian menunjukkan bahwa puncak karakteristik partikel MgO dan Ag tidak muncul pada difraktogram XRD, tetapi secara visual dan morfologis SEM mendukung pembentukan dua partikel dan berdasarkan literatur dari hasil peneliti lain. Selain itu, komposit ini efektif dalam menghambat pertumbuhan kedua bakteri.       ABSTRACT Research on the synthesis of chitosan/MgO/Ag composites with variations in the mass of AgNO3 precursors 0.05 g, 0.1 g, 0.15 g and 0.2 g were synthesized by the coprecipitation method. The resulting composites were characterized using X-Ray Diffractometry (XRD) and Scanning Electron Microscope (SEM). Furthermore, the effectiveness of this composite as an antibacterial was tested, namely Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative). The results showed that the characteristic peaks of MgO and Ag particles did not appear on the XRD diffractogram, but visually and morphologically SEM supported the formation of two particles and based on the literature from the results of other researchers. In addition, this composite is effective in inhibiting the growth of both bacteria.
PEMBUATAN NANOKOMPOSIT KITOSAN/TiO2/Ag DAN ANALISIS AKTIVITASNYA SEBAGAI ANTIBAKTERI Bungan, Gladys K; Aritonang, Henry F; Wuntu, Audy D
CHEMISTRY PROGRESS Vol 14, No 1 (2021)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/cp.14.1.2021.34128

Abstract

Penelitian tentang pembuatan nanokomposit kitosan/TiO2/Ag telah dilakukan dengan menggunakan TiO2sebanyak6 gram dan konsentrasi AgNO3 yaitu 5 mM menggunakan metode reduksi dan impregnasi. Nanokomposit yang dihasilkan dikarakterisasi menggunakan X-Ray diffractometry (XRD), Scanning Electron Microscope-Energy Dispersive x-Ray Spectroscopy (SEM-EDS) dan menganalisis aktivitasnya sebagai anti bakteri terhadap Staphylococcus aureus (Gram positif) dan Escherichia coli (gram negatif). Hasil penelitian menunjukkan bahwa ukuran nanokomposit yang dihasilkan sebesar 56,93 nm. Difraktogram XRD muncul puncak karakteristik partikel TiO2 tetapi partikel Ag kurang terlihat jelas. Namun, berdasarkan data EDS, kedua partikel ini ditemukan pada membran kitosan. Ini menunjukkan bahwa sangat sedikit partikel Ag yang terbentuk atau keterbatasan alat XRD dalam mendeteksi sejumlah kecil partikel. Namun demikian, nanokomposit menunjukkan kemampuannya untuk menghambat pertumbuhan kedua bakteri ini.ABSTRACTResearch on the manufacture of chitosan/TiO2/Ag nanocomposites has been carried out using 6 grams of TiO2 and 5 mM AgNO3 using reduction and impregnation methods.The resulting nanocomposites were characterized using X-Ray diffraction (XRD), Scanning Electron Microscope-Energy Dispersive x-Ray Spectroscopy (SEM-EDS) and analyzed their activity as anti-bacteria against Staphylococcus aureus (Gram positive) and Escherichia coli (gram negative).The results showed that the resulting nanocomposite size was 56.93 nm. The XRD diffractogram showed the peak characteristics of TiO2 particles but the Ag particles were less visible.However, based on EDS data, the two particles were found on the chitosan membrane. This indicates that very few Ag particles are formed or the limitations of XRD devices in detecting a small number of Ag particles.However, the nanocomposites demonstrated their ability to inhibit the growth of these two bacteria.
SINTESIS NANOKOMPOSIT Nata de coco/TiO2/Ag DAN EFEKTIVITASNYA SEBAGAI ANTIBAKTERI TERHADAP BAKTERI Escherichia coli dan Staphylococcus aureus Tinentang, Heriyanto; Aritonang, Henry F; Koleangan, Harry S. J.
CHEMISTRY PROGRESS Vol 14, No 1 (2021)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/cp.14.1.2021.34130

Abstract

Telah dilakukan penelitian tentang kemampuan aktivitas anti bakteri untuk bakteri Staphylococcus aureus (gram positif) dan Escherichia coli (gram negatif) dengan menggunakan nanokomposit nata de coco/TiO2, nata de coco/Ag, dan nata de coco/TiO2/Ag dengan variasi konsentrasi Ag 0,5 M; 0,6 M; 0,7 M; 0,8 M dan 0,9 M  menggunakan metode reduksi kimia. Nanopartikel tersebut dikarakterisasi menggunakan X-Ray Diffractometry (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy  (SEM-EDS) dan anti bakteri. Untuk uji aktivitas antibakteri menggunakan metode kertas cakram dan dilakukan sebanyak dua kali ulangan untuk tiap-tiap sampel dan bakteri yang diuji. Hasil penelitian menunjukan, aktivitas anti bakteri nanokomposit yang paling baik dalam menghambat pertumbuhan bakteri adalah nanokomposit Nata de coco/TiO2/Ag mampu menghambat pertumbuhan bakteri Escherichiacoli dan Staphylococcusaureus, namun nanokomposit tersebut lebih efektif menghambat pertumbuhan bakteri Escherichiacoli.ABSRACT Research on the ability of anti-bacterial activity for Staphylococcus aureus (gram positive) and Escherichia coli (gram negative) bacteria using nata de coco / nanocomposites TiO2, nata de coco / Ag, and nata de coco / TiO2 / Ag with variations of Ag 0,5 M; 0.6 M; 0.7 M; 0.8 M and 0.9 M using the chemical reduction method. Nanoparticles were characterized using X-Ray Diffractometry (XRD), scanning electron microscopy-energy dispersive X-ray spctroscopy  (SEM-EDS) and anti-bacterial actvity. Test the antibacterial activity using the paper disc method and repeated two times for each sample and bacteria tested. The results showed that the good anti-bacterial activity of nanocomposites in inhibiting bacterial growth was nanocomposite nata de coco /TiO2/Ag  able to inhibit the growth of Escherichia coli and S. aureus, but the nanocomposite is more effective in inhibiting the growth of Escherichia  coli bacteria.
SINTESIS NANOPARTIKEL Fe3O4–POLIETILEN GLIKOL (PEG) 6000 DARI PASIR BESI PANTAI HAIS SEBAGAI ADSORBEN LOGAM KADMIUM (Cd) Tatinting, Gabriel Dinnydio; Aritonang, Henry F; Wuntu, Audy D
CHEMISTRY PROGRESS Vol 14, No 2 (2021)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/cp.14.2.2021.37192

Abstract

Telah dilakukan penelitian tentang sintesis nanopartikel Fe3O4 dari pasir besi pantai Hais dengan metode kopresipitasi dan digunakan sebagai adsorben logam kadmium (Cd). Dalam sintesis nanopartikel tersebut digunakan polietilen glikol (PEG) 6000 sebagai agen penstabil ukuran partikel. Nanopartikel yang dihasilkan dikarakterisasi menggunakan X-Ray diffractometry (XRD) dan Scanning electron microscope (SEM) dan hasil penelitian menunjukkan bahwa dengan penambahan PEG 6000 dapat mempengaruhi ukuran partikel Fe3O4 yang dihasilkan. Selanjutnya nanopartikel Fe3O4-PEG 6000 dianalisis kemampuannya sebagai adsorben logam Cd menggunakan spektofotometer serapan atom (AAS). Hasil penelitian menunjukkan bahwa kemampuan nanopartikel Fe3O4-PEG 6000 dalam menyerap logam Cd lebih baik jika dibandingkan dengan nanopartikel Fe3O4 tanpa penambahan PEG 6000.ABSTRACK A research has been carried out on the synthesis of Fe3O4 nanoparticles from the iron sand of Hais beach using the coprecipitation method and the material was used as an adsorbent for Cadmium (Cd) metal. In the synthesis of these nanoparticles, polyethylene glycol (PEG) 6000 was used as a particle size stabilizer. The resulting nanoparticles were characterized using X-Ray diffractometry (XRD) and Scanning electron microscope (SEM) and the results showed that the addition of PEG 6000 could affect the particle size of Fe3O4 produced. Furthermore, Fe3O4-PEG 6000 nanoparticles were analyzed for their ability to adsorb Cd2+ ion using Atomic adsorption spectroscopy (AAS). The results showed that the ability of Fe3O4-PEG 6000 nanoparticles to adsorb Cd2+ ion was better than that of Fe3O4 nanoparticles without the addition of PEG 6000.
Synchronous and asynchronous online learning of advanced statistics during Covid-19 pandemic Jackson Pasini Mairing; Rhodinus Sidabutar; Elyasib Yunas Lada; Henry Aritonang
JRAMathEdu (Journal of Research and Advances in Mathematics Education) Volume 6 Issue 3 July 2021
Publisher : Department of Mathematics Education, Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23917/jramathedu.v6i3.13477

Abstract

Online learning could have negative impacts on learning processes and outcomes. The condition needed to be resolved through the implementation of appropriate online learning approaches. The research was aimed at describing the effectiveness of the implementation of asynchronous and synchronous online learning approaches in students’ learning outcomes and skills of using Microsoft Excel on the Advanced Statistics of Mathematics Education Department from one of the universities in Central Kalimantan. The learning approaches were integrated with mathematics problems, Minitab software and Microsoft Excel, and videos. The research design was experimental research using a one-group posttest-only design. The subjects were chosen by clustered random sampling. They were 18 students of the department in the 2020/2021 academic year. The instruments were a lesson plan, several videos, textbooks, e-books, questionnaires, mathematics problems, mid-test, and final-test. The students learned using textbooks, e-books, and videos and solved the problems independently. Then, they discussed the solutions online in groups through their WhatsApp group (asynchronously). The problem solutions were presented by the students using a class on WhatsApp or video conference platforms (synchronous). The authors collected data by administering the questionnaire and the tests and analyzed the data using a -test and a Wilcoxon test. The results showed that the implementation of the approaches was effective in enhancing the learning outcomes and skills of using Microsoft Excel. Furthermore, most students positively responded to learn independently and all the students positively responded to analyze data using the software.
Performance of Platinum Nanoparticles / Multiwalled Carbon Nanotubes / Bacterial Cellulose Composite as Anode Catalyst for Proton Exchange Membrane Fuel Cells Henry Fonda Aritonang; Vanda Selvana Kamu; Ciptati Ciptati; Djulia Onggo; Cynthia L. Radiman
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 2 Year 2017 (August 2017)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (114.481 KB) | DOI: 10.9767/bcrec.12.2.803.287-292

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Highly dispersed platinum (Pt) nanoparticles / multiwalled carbon nanotubes (MWCNTs) on bacterial cellulose (BC) as anode catalysts for proton exchange membrane fuel cells (PEMFC) were prepared with various precursors and their electro-catalytic activities towards hydrogen oxidation at 70 oC under non-humidified conditions. The composite was prepared by deposition of Pt nanoparticles and MWCNTs on BC gel by impregnation method using a water solution of metal precursors and MWCNTs followed by reducing reaction using a hydrogen gas. The composite was characterized by using TEM (transmission electron microscopy), EDS (energy dispersive spectroscopy), and XRD (X-ray diffractometry) techniques. TEM images and XRD patterns both lead to the observation of spherical metallic Pt nanoparticles with mean diameter of 3-11 nm well impregnated into the BC fibrils. Preliminary tests on a single cell indicate that renewable BC is a good prospect to be explored as a membrane in fuel cell field. 
PENYELESAIAN MASALAH MATEMATIKA BERAKHIR TERBUKA PADA SISWA SMA Jackson Pasini Mairing; Henry Aritonang
FIBONACCI: Jurnal Pendidikan Matematika dan Matematika Vol 4, No 1 (2018): FIBONACCI: Jurnal Pendidikan Matematika dan Matematika
Publisher : Fakultas Ilmu Pendidikan Universitas Muhammadiyah Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1068.645 KB) | DOI: 10.24853/fbc.4.1.61-70

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Kemampuan berpikir tingkat tinggi ditunjukkan oleh kemampuan siswa dalam memecahkan masalah yang memiliki jawaban atau cara penyelesaian lebih dari satu. Masalah demikian disebut masalah berakhir terbuka. Penelitian ini bertujuan mendeskripsikan kemampuan siswa SMA kelas XI dalam menyelesaikan masalah berakhir terbuka. Penelitian ini dilaksanakan menggunakan pendekatan campuran kuantifatif dan kualitatif (blended quntitative-qualitative approach) dengan jenis penelitian deskriptif. Subjeknya adalah 40 siswa kelas XI dari salah satu SMAN di kota Palangka Raya, Kalimantan Tengah. Peneliti memberikan instrumen penelitian yaitu dua masalah matematika berakhir terbuka pada materi lingkaran dan garis singgung lingkaran kepada semua subjek. Masing-masing masalah menuntut siswa untuk menyelesaikan dengan dua cara berbeda. Cara pertama pada masalah bagian (a), dan cara kedua pada bagian (b). Penyelesaian dari setiap subjek diskor menggunakan rubrik holistik. Hasil penelitian menunjukkan rata-rata skor kemampuan siswa dalam memecahkan masalah sebesar 4,63 (maksimum skor = 16) jika dikonversi ke skala 100 menjadi 28,9.. Hanya ada 1 dari 40 siswa (2,5%) yang mampu menyelesaikan Masalah 1 dengan dua cara berbeda. Pada Masalah 2, ada 92,5% yang mampu menyelesaikan dengan satu cara tertentu tetapi belum mampu menyelesaikan dengan cara lainnya. Jadi, tidak ada siswa yang memiliki kemampuan berpikir tertinggi dalam matematika yaitu berpikir kreatif. Kondisi tersebut terjadi karena penyelesaian siswa pada masalah berakhir terbuka hanya didasarkan pada rumus atau prosedur tertentu.
Green Synthesis of Silver Nanoparticles using Lantana camara Fresh Leaf Extract for Qualitative Detection of Hg2+, Cu2+, Pb2+, and Mn2+ in Aqueous Solution Henry Fonda Aritonang; Talita Kojong; Harry Koleangan; Audy Denny Wuntu
Indonesian Journal of Chemistry Vol 21, No 4 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.64902

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This research was focused on the discovery of new environmentally friendly sensors based on nanoscale materials whose main purpose was to detect the presence of heavy metals in aqueous solutions. The environmentally friendly extracellular biosynthetic technique was applied to produce silver nanoparticles (AgNps). The reducing agents used were distilled water and ethanol extract obtained from fresh leaves of Lantana camara. The silver-containing extracts (Ag-extract) were then used to detect the presence of Hg2+, Cu2+, Pb2+, and Mn2+ in aqueous solutions by the colorimetric method using UV-visible spectroscopy. The colloidal synthesis of AgNPs was then monitored by the same method. The spectrum obtained showed peaks between 430 and 450 nm according to the Plasmon absorbance of AgNP. AgNPs' size and shape were characterized using the Transmission Electron Microscopy (TEM) technique, which showed the average size varies from 1.6 to 25 nm. The colorimetric data showed that Ag-extract, both of distilled water or ethanol solvents, was the best for detecting the presence of Hg2+ followed by Mn2+. On the other hand, Ag-extract in distilled water cannot detect Cu2+, Pb2+, and Mn2+ ions, while almost all Ag-extracts in ethanol solvents could identify the presence of these metals.
Penerapan Blended Learning untuk Meningkatkan Hasil Belajar Matematika Siswa Kelas X SMA Setia Deliana Pasaribu; Jackson Pasini Mairing; Walter Punding; Henry Aritonang; Pujja Sari Purnama
Primatika : Jurnal Pendidikan Matematika Vol 11 No 1 (2022)
Publisher : Program Studi Pendidikan Matematika, Fakultas Keguruan dan Ilmu Pendidikan, Universitas Mulawarman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/primatika.v11i1.1007

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Penelitian ini bertujuan untuk mendiskripsikan aktivitas siswa kelas X MIPA 5 dari salah satu SMAN di kota Palangka Raya selama pembelajaran berbasis masalah dengan pendekatan blended learning tipe flipped classroom pada pelajaran matematika serta untuk mengetahui peningkatan hasil belajar matematika siswa setelah menerapkan model blended learning. Jenis penelitian adalah deskriptif dengan pendekatan kuantitatif. Subjek penelitian adalah siswa kelas X MIPA 5 di sekolah tersebut. Pengumpulan data menggunakan instrumen observasi dan tes yang sudah divalidasi oleh 2 dosen Program Studi Pendidikan Matematika Universitas Palangka Raya, dan 1 guru matematika di sekolah tersebut. Hasil penelitian menunjukkan bahwa aktivitas siswa selama pembelajaran berjalan sesuai dengan langkah-langkah pembelajaran flipped classsroom. Rata-rata hasil belajar siswa kelas X MIPA 5 materi Sistem Pertidaksamaan Linear Dua Variabel pada tes individual pertama, kedua, ketiga dan keempat secara berturut-turut sebesar 54,17 (cukup tercapai), 59,89 (cukup tercapai), 78,97 (tercapai), dan 85,78 (sangat tercapai). Lebih lanjut, rata-rata nilai siswa pada dan tes akhir yang mencakup keseluruhan indikator sebesar 73,06 (tercapai). Dengan demikian, penerapan model blended learning dapat meningkatkan hasil belajar matematika siswa SMA. Peningkatan tersebut disebabkan karena peningkatan keaktifan siswa selama pembelajaran dengan blended learning.