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All Journal Jurnal Penelitian Pendidikan Bulletin of Chemical Reaction Engineering & Catalysis PROSIDING SEMINAR KIMIA Jurnal Zarah JITK (Jurnal Ilmu Pengetahuan dan Komputer) Indonesian Journal of Chemistry Jambura Journal of Educational Chemistry Bivalen: Chemical Studies Journal International Journal of Social Science Kresna: Jurnal Riset dan Pengabdian Masyarakat Bulletin of Chemical Reaction Engineering & Catalysis al Kimiya : Jurnal Ilmu Kimia dan Terapan
Ratna Kusumawardani, Ratna
Jurusan Pendidikan Kimia Dan Ilmu Pengetahuan Alam, Fakultas Keguruan Dan Ilmu Pendidikan, ‎Universitas Mulawarman
Agriculture, Biological Sciences & Forestry Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Economics, Econometrics & Finance Education Electrical & Electronics Engineering Environmental Science Health Professions Languange, Linguistic, Communication & Media Medicine & Pharmacology Public Health Social Sciences Other

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Kemampuan kognitif siswa yang diajar dengan model rotating review dan two stay two stray pada pokok bahasan hidrolisis garam Ratna Kusumawardani; Ria Retnowati; Iis Intan Widiyowati
Bivalen: Chemical Studies Journal Vol 3 No 2 (2020)
Publisher : Bachelor Degree Program of Chemical Education - Mulawarman University | Program Studi S-1 Pendidikan Kimia - Universitas Mulawarman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/bcsj.v3i2.443

Abstract

Penelitian ini bertujuan untuk mengetahui perbedaan kemampuan kognitif atara siswa diajar dengan model pembelajaran rotating review dan siswa yang diajar dengan model two stay two stray pada materi hidrolisis garam di SMA Negeri 5 Samarinda, Indonesia. Jenis penelitian ini merupakan penelitian kuantitatif jenis quasi-eksperimental dan desain post-test only control group. Subjek dalm penelitian ini dipilih menggunakan teknik purposive sampling. Terdapat satu kelompok siswa (siswa kelas XI IPA 2) yang diajar menggunakan model pembelajaran rotating review dan satu kelompok siswa (siswa kelas XI IPA 3) yang diajar menggunakan model pembelajaran two stay two stray. Nilai kemampuan kognitif siswa diperoleh dari nilai post test dan ulangan harian. Rata-rata nilai kemampuan kognitif siswa dianalisis menggunakan t-test. Hasil penelitian menunjukkan rata-rata kemampuan kognitif siswa kelas XI IPA 2 dan siswa kelas XI IPA 3 adalah 75,48 dan 70,84. Hasil uji-t menunjukkan kedua nilai rata-rata tesebut berbeda signifikan (α=0,05). Berdasarkan hasil analisis data diperoleh kesimpulan bahwa kemampuan kognitif siswa yang diajar dengan model pembelajaran rotating review lebih baik daripada kemampuan kognitif siswa yang diajar menggunakan model pembelajaran two stay two stray.
Pengaruh model pembelajaran POGIL dengan metode praktikum terhadap kemampuan kognitif siswa pada materi kelarutan dan hasil kali kelarutan Dini Yulia Sari; Iis Intan Widiyowati; Ratna Kusumawardani
Bivalen: Chemical Studies Journal Vol 3 No 2 (2020)
Publisher : Bachelor Degree Program of Chemical Education - Mulawarman University | Program Studi S-1 Pendidikan Kimia - Universitas Mulawarman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/bcsj.v3i2.445

Abstract

Penelitian ini bertujuan untuk mengetahui kemampuan kognitif siswa pada pokok bahasan kelarutan dan hasil kali kelarutan (Ksp) setelah diajar dengan model pembelajaran process-oriented guided-inquiry learning (POGIL) dengan metode praktikum. Sampel dalam penelitian ini adalah dua kelompok siswa SMA kelas XI jurusan IPA. Kemampuan kognitif siswa diperoleh melalui tes. Data dianalisis menggunakan uji normalitas dengan metode Chi-Square, uji homogenitas menggunakan uji F dan uji perbedaan menggunakan uji t. Hasil penelitian menunjukkan nilai rata-rata kemampuan kognitif siswa kelas eksperimen dan kelas kontrol berturut-turut adalah 75,85 dan 71,05. Penelitian ini menunjukkan bahwa terdapat pegaruh signifikan (5%) penggunaan model pembelajaran POGIL dengan metode praktikum terhadap kemampuan kognitif siswa pada materi kelarutan dan hasil kali kelarutan.
Pengaruh model pembelajaran process oriented guided inquiry learning terhadap hasil belajar siswa SMK pada pokok bahasan laju reaksi Tamara Claudya Susanti; Ratna Kusumawardani; Abdul Majid
Bivalen: Chemical Studies Journal Vol 4 No 1 (2021)
Publisher : Bachelor Degree Program of Chemical Education - Mulawarman University | Program Studi S-1 Pendidikan Kimia - Universitas Mulawarman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/bcsj.v4i1.718

Abstract

Penelitian ini bertujuan untuk mengetahui pengaruh penerapan model pembelajaran process oriented guided inquiry learning (POGIL) terhadap hasil belajar siswa sekolah menengah kejuruan (SMK) pada pokok bahasan laju reaksi. Penelitian ini menggunakan desain intact group comparison. Penelitian dilaksankan di SMK Negeri 6 Samarinda, Kalimantan Timur, Indonesia. Sampel adalah 2 (dua) kelompok siswa yang diambil dengan teknik purposive sampling. Satu kelas siswa diajar dengan model pembelajaran POGIL dan satu kelas siswa yang lain diajar dengan menggunakan model pembelajaran langsung. Hasil belajar siswa diperoleh melalui tes yang diberikan pada post-test dan ulangan harian. Adanya pengaruh diuji menggunakan uji t pada taraf signifikan 5%. Hasil penelitian menunjukkan bahwa rata-rata hasil belajar siswa yang diajar dengan model pembelajaran POGIL (71,71) berbeda signifikan dengan rata-rata hasil belajar siswa yang diajar dengan model pembelajaran langsung (66,46). Hasil ini menunjukkan bahwa terdapat pengaruh penerapan model pembelajaran POGIL terhadap hasil belajar siswa SMK pada pokok bahasan laju reaksi.
INTERACTIVE POWERPOINTS IN ONLINE TGT-BASED MODELS ON THERMOCHEMICAL MATERIALS Ratna Kusumawardani; Muhamad Hamami Nata; Iis Intan Widiyowati
International Journal of Social Science Vol. 1 No. 4: December 2021
Publisher : Bajang Institute

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.53625/ijss.v1i4.702

Abstract

The closure of schools due to the Covid-19 pandemic has forced all schools in Indonesia to be closed temporarily, therefore learning must be carried out online. Online learning is commonly carried out with teacher presentations and assignments therefore this makes learning monotonous and boring for students. So we need a medium that makes learning more interesting, namely with interactive powerpoints. The purpose of this study was to determine the effect of using interactive powerpoints in the online-based TGT model on thermochemistry material. This type of research is quasi-experimental research with a post-test only control group design. The data collection technique used the technique of daily test tests, documentation, and student perception questionnaires. The data were analyzed using the normality test, F test, and t test with a significance level of 5%. The results showed that before being given the treatment, the two classes were normally distributed, homogeneous variations and there was no difference in student absorption. After being given the treatment, the two classes had significant differences in absorption. Therefore it can be concluded that there is an effect of using interactive powerpoints in the online-based TGT model on thermochemistry material.
PEMANFAATAN TULANG AYAM SEBAGAI ADSORBEN METHYLENE BLUE Maulina Maulina; Devira Nur Ajizah; Indah Nur Fitriana; Anita Setiawati; Khusnul Khotimah; Devi Listianingrum; Ratna Kusumawardani
Jurnal Zarah Vol. 10 No. 2 (2022): Jurnal Zarah
Publisher : Prodi Pendidikan Kimia, FKIP, Universitas Maritim Raja Ali Haji

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31629/zarah.v10i2.3980

Abstract

Penelitian ini bertujuan untuk mengetahui pemanfaatan tulang ayam sebagai adsorben methylene blue. Limbah tulang ayam banyak ditemukan di lingkungan masyarakat namun jarang dimanfaatkan atau bahkan tidak dimanfaatkan. Hal ini tentunya menimbulkan masalah lingkungan akibat sisa tulang yang tidak memiliki nilai ekonomi. Zat warna methylene blue merupakan pewarna sintetik yang dapat membahayakan makhluk hidup. Oleh karena itu, perlu dilakukan upaya adsorbsi zat warna dari lingkungan makhluk hidup, dengan menggunakan adsorben dari limbah tulang ayam. Penelitian ini menggunakan metode eksperimen, dengan cara mengukur keadaan awal jenis sampel sampai dengan mengukur keadaan setelah diberi perlakuan. Hasil penelitian menunjukkan kadar zat yang teradsorbsi maksimum berada pada kecepatan pengadukan 150 rpm pada serbuk dan abu tulang ayam sebesar 72,947% dan 64,183%. Pada konsentrasi optimum menunjukkan kadar zat yang teradsorbsi berada pada konsentrasi 125 ppm pada serbuk dan abu tulang ayam sebesar 58,710% dan 66,167%. Sedangkan pada pH optimum menunjukkan kadar zat yang teradsorbsi pada serbuk adalah pH 9 sebesar 78,831% dan pada abu adalah pH 7 sebesar 67,997%. Dapat simpulkan bahwa limbah tulang ayam dapat mengadsorbsi zat warna methylene blue.
DECISION SUPPORT SYSTEM FEASIBILITY OF GRANTING RECEIVABLES ON GOODS EXPORT SERVICES IN FREIGHT FORWARDING COMPANY WITH PROFILE MATCHING METHOD sebastian, Ivan; Jumaryadi, Yuwan; Kusumawardani, Ratna; Setiawan, Bayu
JITK (Jurnal Ilmu Pengetahuan dan Teknologi Komputer) Vol 7 No 1 (2021): JITK Issue August 2021
Publisher : LPPM Nusa Mandiri

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1202.443 KB) | DOI: 10.33480/jitk.v7i1.1644

Abstract

Decision Support System (DSS) is a system that is able to provide problem solving skills in both semi-structured and unstructured ways. The company's role in the import-export business is very important because it can meet the needs of people who have been doing business in the trade sector, both domestic trade and international trade. Indonesia as a country with a high volume of international trade requires a transportation service company that can support goods export activities by providing payment facilities with a certain time period. The problem that occurs is that there are customers who experience congestion in payment of receivables. This is because there is no standardized procedure in determining the granting of receivables so that it is difficult to determine the feasibility of granting receivables to customers. Therefore, researchers will conduct research on a decision support system with the profile matching method to determine the feasibility of granting receivables to goods export services by applying the 5C principle so that decision makers do not use intuition again and have methods or standardized procedures in providing receivables to customers. This research is expected to help determine the feasibility of receivables by applying the 5C principle, it is hoped that it can help decision makers in making decisions about giving credit to customers.
Kinetic Study of Styrene Oxidation over Titania Catalyst Supported on Sulfonated Fish Bone-derived Carbon Ratna Kusumawardani; Mukhamad Nurhadi; Teguh Wirawan; Anton Prasetyo; Nabila Nur Agusti; Sin Yuan Lai; Hadi Nur
Bulletin of Chemical Reaction Engineering & Catalysis 2022: BCREC Volume 17 Issue 1 Year 2022 (March 2022)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.17.1.13133.194-204

Abstract

The kinetic evaluation of titania supported sulfonated fish bone-derived carbon (TiO2/SFBC) as a catalyst in styrene oxidation by aqueous hydrogen peroxide was carried out. The catalysts were prepared by carbonation of fishbone powder at varying temperatures 500, 600 and 700 °C, respectively for 2 h, followed by sulfonation with sulfuric acid (1M) for 24 h and impregnated by varied titania concentration 500, 1000 and 1500 µmol. The physical properties of catalysts were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Scanning Electron Microscope-Energy Dispersive X-Ray (SEM-EDX) and the nitrogen adsorption-desorption analysis. The catalytic activity result showed that TiO2/SFBC can be used as a potential catalyst in styrene oxidation. Worth noting that the sulfonation process has not only transformed the TiO2/FBC particulates (without sulfonation) to cuboid-shaped TiO2/SFBC (with sulfonation) but also contributed to the high selectivity of benzaldehyde. On the other hand, carbonization at different temperatures has an indistinct effect on catalytic performance due to their similar surface areas. The styrene conversion rate responded positively with the increasing amount of titania in the functionalized composites. The styrene oxidation by aqueous H2O2 unraveled the first-order reaction with the activation energy of ⁓63.5 kJ. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Carbon-containing Hydroxyapatite Obtained from Fish Bone as Low-cost Mesoporous Material for Methylene Blue Adsorption Mukhamad Nurhadi; Ratna Kusumawardani; Wirhanuddin Wirhanuddin; Rahmat Gunawan; Hadi Nur
Bulletin of Chemical Reaction Engineering & Catalysis 2019: BCREC Volume 14 Issue 3 Year 2019 (December 2019)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.14.3.5365.660-671

Abstract

The carbon-containing hydroxyapatite has been synthesized using the fish bone obtained from East Kalimantan, Indonesia. The synthesis was conducted at varying calcination temperature (300-700 °C) and duration time (1-5 h). The carbon-containing hydroxyapatite were characterized by using Nitrogen adsorption-desorption, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Thermogravimetric analysis (TGA) and Differential thermal analysis (DTA). The carbon-containing hydroxyapatite nanoparticles consisted of the mesoporous structure with a specific surface area of 159 m2.g-1 and pore size of 44 Å. The carbon-containing hydroxyapatite nanoparticles were utilized as the adsorbent for the removal of methylene blue by varying the contact time, initial dye concentration, pH, adsorbent dosage and temperature. The maximum amount of adsorption capacity was 56.49 mg.g-1. The adsorption was well fitted with the Langmuir adsorption model (R2 ~ 0.998) and the pseudo-second-order model. This indicated that the dye molecules were adsorbed on the surface-active site of carbon-containing hydroxyapatite via chemical binding, forming an adsorbate monolayer. Hence, the adsorption capability corresponds to the physical properties such as the surface area and pore volume of hydroxyapatite because the larger surface area consists of higher binding sites for the adsorption. Thermodynamic parameters, including the Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS), indicated that the adsorption of methylene blue onto the carbon-containing hydroxyapatite nanoparticles was spontaneous. Thus, carbon-containing hydroxyapatite nanoparticles can be applied as a low-cost adsorbent for the treatment of industrial effluents that are contaminated with the methylene blue.  
Catalytic Performance of TiO2–Carbon Mesoporous-Derived from Fish Bones in Styrene Oxidation with Aqueous Hydrogen Peroxide as an Oxidant Mukhamad Nurhadi; Ratna Kusumawardani; Teguh Wirawan; Sumari Sumari; Sin Yuan Lai; Hadi Nur
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 1 Year 2021 (March 2021)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.1.9729.88-96

Abstract

The catalytic performance of titania-supported carbon mesoporous-derived from fish bones (TiO2/CFB) has been investigated in styrene oxidation with aqueous H2O2. The preparation steps of (TiO2/CFB) catalyst involved the carbonization of fish bones powder at 500 °C for 2 h. followed by impregnation of titania using titanium(IV) isopropoxide (500 µmol) precursor, and calcined at 350 °C for 3 h. The physical properties of the adsorbents were characterized using Fourier transform infrared, X-ray diffraction (XRD), Scanning electron microscopy with energy dispersive X-ray (SEM-EDX), and nitrogen adsorption-desorption studies. The catalytic test was carried out using styrene oxidation with H2O2 as an oxidant at room temperature for 24 h. Its catalytic activity was compared with Fe2O3/CFB, CuO/CFB, TiO2, and CFB catalysts. It is demonstrated that the catalytic activity of TiO2/CFB catalyst has the highest compared to Fe2O3/CFB, CuO/CFB, TiO2, and CFB catalysts in the oxidation of styrene with styrene conversion ~23% and benzaldehyde selectivity ~90%. Kinetics of TiO2/CFB catalyzed oxidation of styrene has been investigated and mechanism for oxidation of styrene has been proposed. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA   License (https://creativecommons.org/licenses/by-sa/4.0). 
Activated Bledug Kuwu’s Clay as Adsorbent Potential for Synthetic Dye Adsorption: Kinetic and Thermodynamic Studies Sri Lestari; Muflihah Muflihah; Ratna Kusumawardani; Mukhamad Nurhadi; Yuniati Mangesa; Fathur Insani Ridho; Robbiatul Adawiyah; Pristiningtyas Ambarwati; Siti Rahma; Sin Yuan Lai; Hadi Nur
Bulletin of Chemical Reaction Engineering & Catalysis 2022: BCREC Volume 17 Issue 1 Year 2022 (March 2022)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.17.1.12473.22-31

Abstract

Bledug Kuwu is one of the geological phenomena as a mud volcano that occurs in Kuwu, Purwodadi, Grobogan, Central Java, Indonesia. The evaluation of Bledug Kuwu’s clay as one of the adsorbents for synthetic dyes has been carried out. The preparation of the adsorbent started with washing the clay with distilled water, followed by activation with a solution of hydrochloric acid (1 M) under mechanistic stirring for overnight. The C−H and O−H groups found on the clay adsorbent could attract methylene blue by dispersion forces and hydrogen bonding. Hydrocloric acid activation process for clay can increase surface area from 49 to 70 m2.g−1, meanwhile, reducing the average crystal size from 48.3 to 43.4 nm. The dye removal capacity increased from 34 to 40 mg.g−1 in corresponding to the increase of the temperature from 30 to 50 °C. The results showed that the equilibrium adsorption capacity of activated Bledug Kuwu’s clay reached 99% in an adsorption time of 20 min. The kinetic models of methylene blue adsorption onto BKC and ABKC adsorbents follow the pseudo-second order and the adsorption process is spontaneous with free energy (ΔG) as −23.519 kJ.mol−1. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Co-Authors A. Rismawati Abdul Majid Abdul Majid Agus Harisandi Akrajas Ali Umar Ana Fatimah Arma Ani Suryani Simbolon Anita Setiawati Anton Prasetyo Atiek Rostika Noviyanti Bayu Setiawan Darna Yunita Devi Listianingrum Devira Nur Ajizah Dini Yulia Sari Eka Parmawatika Fathur Insani Ridho Hadi Nur Hadi Nur Hadi Nur Hadi Nur Hadi Nur Hadi Nur Hadi Nur Hadi Nur Ida Ayu Putu Sri Widnyani Iis Intan Widiyowati Indah Nur Fitriana Ivan Sebastian Jumaryadi, Yuwan Maulina Maulina Mohammad Syafrullah muflihah muflihah Muhamad Hamami Nata Mukhamad Nurhadi Mukhamad Nurhadi Mukhamad Nurhadi, Mukhamad Nabila Nur Agusti Nugraha Abdullah, Indra Nurlaili, Nurlaili Pratiwi, Ajeng Hayu Pristiningtyas Ambarwati Purwanto Purwanto Putri Wulan Mayangsari Rahmat Gunawan Rexy Anderson Tindangen Ria Retnowati Ria Retnowati Rindoi, Muhammad Robbiatul Adawiyah Rony, Zahara Tussoleha Ruwirohi, Jan Everhard Samidi Samidi Serly Wahyuni Salosso Sin Yuan Lai Sin Yuan Lai Sin Yuan Lai Sin Yuan Lai Siti Nurjanah Siti Rahma Sri Lestari Sri Rahma Wati Sukemi Sukemi Sumari Sumari Tamara Claudya Susanti Teguh Wirawan Teguh Wirawan Triana Anggraini Tutik Sri Susilowati Wa Rizka Hafinah Watulingas, Maasje C. Wirhanuddin Wirhanuddin Yulianawati Yuni Kurnia Yuniati Mangesa