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MENINGKATKAN KEMAMPUAN KOMUNIKASI DAN DISPOSISI MATEMATIK SISWA SEKOLAH MENENGAH ATAS MELALUI PEMBELAJARAN GENERATIF Isnaeni, Isnaeni; Maya, Rippi
Jurnal Pengajaran MIPA Vol 19, No 2 (2014): JPMIPA: Volume 19, Issue 2, 2014
Publisher : Faculty of Mathematics and Science Education, Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18269/jpmipa.v19i2.36175

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ABSTRAKPenelitian ini merupakan suatu kuasi eksperimen berdesain pretes-postes kelompok kontrol dengan tujuan menelaah kemampuan komunikasi, dan disposisi matematik siswa melalui pembelajaran generatif. Laporan ini adalah bagian dari penelitian tesis dengan subyek penelitian sebanyak 70 siswa kelas X dari satu SMA Negeri di Cimahi. Instrumen penelitian terdiri dari satu tes uraian komunikasi matematik, dan satu skala disposisi matematik. Penelitian menemukan bahwa kemampuan komunikasi siswa yang memperoleh pembelajaran generatif mencapai mutu yang cukup baik dan itu lebih baik daripada mutu siswa yang memperoleh pembelajaran konvensional. Namun penelitian ini juga menemukan tidak ada perbedaan disposisi matematik siswa pada kedua pembelajaran dan disposisi matematik siswa telah tergolong cukup baik. Selain itu, penelitian ini juga menemukan terdapat asosiasi antara kemampuan komunikasi matematik, dan disposisi matematik, serta siswa menunjukkan persepsi yang baik terhadap pembelajaran generatif. ABSTRACTThis paper reported the findings from a pretest-postest experimental control group design conducted in 2014 by using generative teaching-learning to investigate students’ mathematical communication ability and mathematical disposition. This report was a part of a master thesis that involved 70 tenth grade students from a senior high school in Cimahi. The instruments of the study were an essay mathematical communication test, a mathematical disposition scale, and a students’ perception toward generative teaching-learning scale. The study found that in terms of mathematical communication ability, the grade of students taught by generative teaching-learning was better than the grade of students taught by conventional teaching. However, in terms of mathematical disposition there were no grades difference between students taught by generative teaching-learning and students taught by conventional teaching, and those grades were fairly good. Moreover, students’ perception to generative teaching-learning was good and there was association between mathematical communication and mathematical disposition.
Assisted Surface-state Recombination of Orange-peel Carbon Nanodots in Various Matrices Fatimah, Siti; Isnaeni, Isnaeni; Tahir, Dahlang
Makara Journal of Science Vol. 22, No. 1
Publisher : UI Scholars Hub

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Abstract

The contentious origin of the luminescence of carbon nanodots (CDs) has attracted considerable attention. In this work, we synthesized CDs from orange peel by using a microwave-assisted technique. We investigated the optical properties of the synthesized CDs. Moreover, we studied the effect of matrix addition on the optical properties of CDs. We found that matrix addition significantly influences the absorbance and photoluminescence of CDs. Shifts in absorbance peak intensity and emission peak wavelength indicated that the bonding of matrix molecules on the surfaces of the CDs has changed the structures of CDs. This finding is supported by the extended half-life of CDs after matrix addition. Our results will expand researchon the use of CDs as phosphorescent materials.
Optical Properties of Toluene-soluble Carbon Dots Prepared from Laser-ablated Coconut Fiber Isnaeni, Isnaeni; Suliyanti, Maria Margaretha; Shiddiq, Muhandis; Sambudi, Nonny Soraya
Makara Journal of Science Vol. 23, No. 4
Publisher : UI Scholars Hub

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Abstract

In this study, we used laser ablation to fabricate toluene-soluble carbon nanoparticles from coconut fiber. In response to excitations at various wavelengths, the fabricated carbon nanoparticles exhibit three distinctive emission peaks at wavelengths of 300 nm, 440 nm, and 540 nm. These three emission peaks correspond to the  orbital state,  orbital state, and surface state, respectively. Photoluminescence excitation measurements indicate a high probability of energy transfer between the surface state and  orbital state, whereas the  orbital state is likely independent of the other states. The results of time-resolved photoluminescence measurements indicate that electrons are likely to remain longer in higher-energy states. Given that the carbon dots fabricated in this study were made from natural resources, these findings may find application in photonic devices that feature tunable emissions.
Identification of Paracetamol and Caffeine in Jamu Powders Simultaneously Using TLC-Densitometry Wahyuningsih, Etik; Isnaeni, Isnaeni; Asri Darmawati; Annisa Kartika Sari
Berkala Ilmiah Kimia Farmasi Vol. 10 No. 1 (2023): June
Publisher : Universitas Airlangga

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/bikfar.v10i1.44242

Abstract

Paracetamol and caffeine were chemical compounds suspected to be illegally added to traditional herbs claimed as rheumatics drugs. Identification of paracetamol and caffeine was conducted on five samples of jamu powder obtained from the Depot Jamu in Surabaya. This study aimed to simultaneously identify paracetamol and caffeine commonly found in traditional medicine, one of which was jamu powder, using thin-layer chromatography densitometry (TLC-Densitometry). Evaluation of the presence of paracetamol and caffeine in the product of jamu was performed by thin-layer chromatography with silica gel GF254 and chloroform-ethyl acetate (1:1) as the stationary and mobile phases, respectively. The spots on the TLC plate were detected using a UV light at 254 nm, and the areas were measured by a Camag TLC scanner. The TLC profile demonstrated good separation of paracetamol, caffeine, and other substances contained in the products. The retardation factors (Rf) of paracetamol and caffeine were 0,42 and 0,26, with detection limits of 0,0125 µg/spot and 0,05 µg/spot, respectively. The simultaneous identification of caffeine and paracetamol using thin-layer chromatography densitometry revealed that none of the five samples were detected to contain paracetamol and caffeine. Keywords:  Simultaneously, Identification, Paracetamol, Caffeine, Jamu Powder, TLC- Densitometry
Color Stability and Antioxidant Activity of Red Roselle (Hibiscus Sabdariffa L.) Calyx Infuse Sholika Sari, Trisiyana; Kusumawati, Idha; Isnaeni, Isnaeni
Berkala Ilmiah Kimia Farmasi Vol. 10 No. 2 (2023): December
Publisher : Universitas Airlangga

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/bikfar.v10i2.51706

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The roselle flower (Hibiscus sabdariffa L.), was known as a potential functional food source because of its antioxidant and antibacterial properties. Apart from that, it was also used as a natural dye because of its red color. Antioxidant compounds in roselle flowers included neo-chlorogenic acid, chlorogenic acid, crypto- chlorogenic acid, routine, and isoquercitrin. The high content of these antioxidant compounds often causes color instability. For this reason, this research would analyzed the effect of temperature and long storage on color changes and the antioxidant activity of a red roselle flower infusion. Storage conditions were carried out with three temperature variations, namely cold temperature (2–8℃), cool temperature (8–15℃), and room temperature (15–30℃), with a long storage of 8 days. The stability parameters used were color changes and activity as an antioxidant. Color changes were measured using a chromameter, while the antioxidant activity was measured by the IC50 value using the DPPH method. The principle of this method was based on a purple color change reaction, which faded, and then the inhibitory intensity against DPPH was measured using UV-Vis spectrophotometer. It was found that the color values had significant differences visible from the first day storage at the room temperature (30℃), cool temperature (11℃), and cold temperature (6℃). Thus, there was an influence of temperature and long storage on the color change of boiled red roselle flower calyx. A significant decrease in activity was seen on the first day storage at room temperature (30℃) and third day storage at cool temperature (11℃). Meanwhile, at cold temperatures (6℃), there was no significant effect on the reduction in activity from boiling red roselle flower calyx for up to 8 days of storage. Keywords:  Red Rosela, Stability, Infuse, Color, Antioxidant
The Effectiveness of Vitamin E Soft Capsules as an Antioxidant Putri, Syakirah Yasmin; Isadiartuti, Dewi; Isnaeni, Isnaeni; Aulya Farah Fahreza; Alvina Violita Mulyanto Putri; Zulfa Diana; Nafa Nazilatul Fatihah; I Gede Rekyadji Arimbawa; Alya Fakhirah; Talitha Nabilla Wijayanata; Muhammad Pramudya Pangestu; Azzalia Firdanthi; Oudrey Addriana; Umi Aida Rohma
Berkala Ilmiah Kimia Farmasi Vol. 11 No. 1 (2024): June
Publisher : Universitas Airlangga

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/bikfar.v11i1.51902

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Antioxidants inhibited the oxidation of other molecules and played an important role in maintaining a healthy body. Antioxidants were found in fruits, vegetables, all parts of plants, and were present in the body as enzymes or products of metabolism. Vitamin E referred to a large number of natural or synthetic compounds, with alpha-tocopherol being the most active and widely distributed form in nature. Alpha-tocopherol was the most active antioxidant form of vitamin E and served as the primary lipophilic antioxidant in plasma, membranes, and tissues. The most important function of vitamin E was its antioxidant capability, counteracting free radical attacks that could damage cells and cause various degenerative diseases. Additionally, antioxidants helped reduce the effects of photoaging on the skin, potentiated anti-aging and anti-inflammatory activity, increased the rate of wound healing, and helped maintain healthy eyes and the immune system. One form of vitamin E dosage form was a soft capsule, which had several advantages, including the ease of filling the Active Pharmaceutical Ingredient (API) in liquid form, higher production capacity, and formulation uniformity compared to gelatin tablets or hard capsules. Soft capsule preparations also had rapid API release, which could result in achieving therapeutic blood levels more quickly and achieving greater bioavailability. This study aimed to evaluate soft capsule dosage forms in enhancing the effectiveness of vitamin E as an antioxidant. The research utilized review articles sourced from national and international journals, as well as scientific journals. The results showed that vitamin E supplementation in soft capsules could increase its effectiveness as an antioxidant.Keywords:  Soft Capsule, Increase Effectiveness, α-tocopherol, Vitamin E, Antioxidant
IMPLEMENTASI PEMBELAJARAN MATEMATIKA BERWAWASAN LINGKUNGAN DENGAN PENDEKATAN KOOPERATIF GUNA MENGEMBANGKAN SIKAP RAMAH LINGKUNGAN DAN MENINGKATKAN HASIL BELAJAR SISWA Hidayati, Kana; Arliani, Elly; Retnawati, Heri; Isnaeni, Isnaeni
PYTHAGORAS Jurnal Pendidikan Matematika Vol 4, No 1: Juni 2008
Publisher : Department of Mathematics Education, Faculty of Mathematics and Natural Sciences, UNY

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (128.707 KB) | DOI: 10.21831/pg.v4i1.685

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Penelitian ini bertujuan meningkatkan hasil belajar matematika dan mengembangkan sikap ramah lingkungan pada siswa SMA Muhammadiyah 1 Yogyakarta melalui pembelajaran matematika berwawasan lingkungan dengan pendekatan kooperatif serta mengetahui respons siswa terhadap kegiatan pembelajaran yang dilakukan. Kegiatan penelitian dilakukan melalui penelitian tindakan kelas. Tindakan dilaksanakan dalam 2 siklus pada kelas XI IPA 3 SMA Muhammadiyah 1 Yogyakarta. Kegiatan siklus I meliputi perencanaan, tindakan, observasi, dan refleksi. Kegiatan siklus II merupakan tindak lanjut dan modifikasi dari siklus I. Pengumpulan data dilakukan menggunakan pedoman wawancara, lembar observasi pelaksanaan pembelajaran, soal kuis dan tugas, serta angket respons siswa. Pendekatan kooperatif dalam penelitian ini menggunakan tipe Student Teams-Achievement Divitions (STAD) dan dilakukan pada materi Peluang. Hasil penelitian menunjukkan bahwa melalui kegiatan pembelajaran matematika berwawasan lingkungan dengan pendekatan kooperatif tipe STAD terjadi peningkatan hasil belajar siswa pada materi Peluang dan dapat mengembangkan sikap ramah lingkungan pada siswa. Kegiatan pembelajaran matematika tersebut dilakukan dengan tahapan–tahapan sebagai berikut: (1) Class Presentation (Presentasi Kelas), (2) Team Study, (3) Quizzes (Kuis), dan (4) Reward (Penghargaan kelompok). Respons siswa terhadap kegiatan pembelajaran baik dan siswa merasa semakin peduli dengan lingkungannya dan semakin mengerti bahwa matematika ternyata sangat dekat dengan kehidupan sehari-hari para siswa.  Kata kunci :  Pembelajaran kooperatif, berwawasan lingkungan, hasil belajar, sikap                        ramah    lingkungan 
Reducing Ammonia (NH3) Levels in Fish Cage Water Using Activated Carbon Adsorbent Derived from Purple Corn Cob Hamid, Muhammadin; Nasution, Tulus Ikhsan; Elfinita, Revi; Wijoyo, Hadi; Isnaeni, Isnaeni
Science and Technology Indonesia Vol. 9 No. 3 (2024): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.3.669-681

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Successfully made adsorbent of activated carbon made from purple corn cob which aims to minimize ammonia (NH3) levels found in water in fish farming with cage ponds. Activated carbon using carbonization method with a change in temperature that is between 550°C, 600°C, and 650°C and activation using Na2CO3 solution as activator. Activated carbon that has been obtained has exceeded the standard of SNI No.06-3730-1995, with characteristics including carbon yield ranging from 79.71% to 89.85%, moisture content ranging from 11.3% to 25.4%, volatile matter content ranging from 10.10% to 24.5%, ash content ranging from 9.7% to 9.9%, and fixed carbon content ranging from 65.7% to 79.7%. Then test results were obtained such as CO2 functional groups were found to enhance the adsorption process. Activated carbon displays the presence of a predominantly amorphous structure but also revealed a crystalline carbon structure. The highest peak was obtained at 29.7° with Miller index (201). The activated carbon displays the presence of pores on the scattered surface with carbon elements dominating. Adsorption mechanism to reduce ammonia (NH3) using activated carbon due to intermolecular interaction process. So that when testing the application for ammonia absorption, the best results were obtained in the sample with an adsorbent mass of 1.50 g at a carbonization temperature of 650°C with an adsorption capacity value of 546.34 mg/g and ammonia reduction of 82%. This research can open up opportunities for the potential development of new materials, especially for fish farming through cage techniques.
SYNTHESIS AND CHARACTERIZATION ANALYSIS OF FE3O4/SiO2 CORE SHELL Cassia, Diva; Sugihartono, Iwan; Isnaeni, Isnaeni; Soewoto, Haswi Purwandanu; Alaih, Akhmad Futukhillah Fataba; Triyono, Djoko; Mohar, Rahmat Setiawan; Tiam, Tan Swee
Spektra: Jurnal Fisika dan Aplikasinya Vol 8 No 3 (2023): SPEKTRA: Jurnal Fisika dan Aplikasinya, Volume 8 Issue 3, December 2023
Publisher : Program Studi Fisika Universitas Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21009/SPEKTRA.083.04

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Fe3O4/SiO2 core shell synthesis has been carried out, and its characteristics has been analyzed to be used as a photocatalyst using co-precipitation and sol-gel method. Fe3O4 is used as the core material to eliminate the difficulty of separating the photocatalyst powder from the solution medium, SiO2 is used to avoid oxidation by preventing the Fe3O4 core from coming into direct contact with the solution. The samples were then characterized using X-Ray Diffraction (XRD), Fourier Transform Infra-Red (FTIR), and Vibrating Sample Magnetometer (VSM). The XRD and FTIR results showed that the crystal structure and movement of the sample molecules matched the standard characteristics from previous studies. The VSM characterization results show that SiO2 succeeded in reducing the value of the magnetization of Fe3O4, which proves that Fe3O4 has been successfully coated by SiO2.
Sintesis dan Karakterisasi Magnetik Kuantum Dot Fe3O4 Dengan Metode Kopresipitasi Hamid, Abdul; Isnaeni, Isnaeni; Amran, Ali; Beri, Deski
Periodic Vol 13, No 2 (2024): PERIODIC
Publisher : Departemen Kimia FMIPA UNP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/periodic.v13i2.124698

Abstract

The unique properties of the magnetic quantum dot Fe3O4 make it widely synthesized by different methods and applied in the biomedical field. The synthesis method plays an important role in determining the optical properties of the magnetic quantum dot Fe3O4. This study aims to determine the magnetic synthesis of quantum dot Fe3O4 coated with oleic acid by coprecipitation method. Quantum dot Fe3O4 magnetic synthesis method by coprecipitation using oleic acid for functionalization of Fe3O4 quantum dot magnetic. The results of the FTIR analysis showed five main absorption bands namely O-H, C-H, C=C, C-O, and Fe-O which indicated that the magnetic quantum dot Fe3O4 was successfully functionalized with oleic acid.
Co-Authors Abdillah, Roby Abdul Hamid Achmad Basori, Achmad Achmad Toto Poernomo Adi Fadli Adillah, Rifda Al As'ary, Muawwal Alaih, Akhmad Futukhillah Fataba Ali Amran Ali Imran Alvina Violita Mulyanto Putri Alya Fakhirah Anida Zulfa, Baiq Annisa Kartika Sari Anwar, Nazwa Zahira Ardiana, Alma Dita Ari Asnani As'ary, Muawwal Al Asiandi Asiandi, Asiandi Asri Darmawati As’ary, Muawwal Al AT, Poernomo Aty Widyawaruyanti Aulya Farah Fahreza Ayumuyas, Nur Palestin Ayuni, Nur Azizah, Mir’ah Azka, Aril Danish Azmi, Vania Amelia Azzahra, Chofifatus Solecha Azzalia Firdanthi Basyaruddin, Muh Budi Utomo Calvina, Aisha Bella Cassia, Diva Cholisoh, Lilis Dadan Hermawan, Dadan Dahlang Tahir Debi Yustisia, Wa Ode Deski Beri Dewi Isadiartuti Dinda Annisya, Sukma Diyah, Nuzul Wahyuning Djoko Agus Purwanto Eddy Bagus Wasito Elfinita, Revi Elly Arliani Esti Hendradi Etik Wahyuningsih Fajarli Apriani M, Baiq Faradillah Rusliana Febrianti, Suhaemi Firna, Firna Fitri, Andi Fitri Geminastiti Sakkir Hadi Poerwono Hadi, M. Warisul Haerunisa, Haerunisa Hakimi, Ahmad Reza Hamid, Muhammadin hasani, riadhatul Hendrawan Hendrawan Heri Retnawati Hidayat, Rabiyatun Hidayati, Shabrina Wahyu I Gede Rekyadji Arimbawa Idha Kusumawati Ikmawati, Isna Ita Sarmita Samad, Ita Sarmita Iwan Sugihartono Iyon Titok Sugiarto Julham Hukom Juliansyah, Irgi Zaini Kamaruddin, Harni Sartika Kana Hidayati Kartuti Debora, Kartuti Kholis Amalia Nofianti Kristianti, Rayi Kurnijasanti, R Larasati, Rini Lestari Widiantika, Susi Lestari, Ismira Wahyu Lewa, Ismira Wahyu Lestari Lisdayanti, Nur Lucky Anugrah, Riska Mahmudah, Rifaatul Maria Margaretha Suliyanti Martila, Lenny Intan Masmira, Ade Miladya, Nanda Fadlilatul Mirzautika, Anggita Mohar, Rahmat Setiawan Muhammad Pramudya Pangestu Mulyawan, Reynaldi Gilang Nafa Nazilatul Fatihah Nisa, Asriatun Nurhasanah, Wahidatun Dewi Nurhayati Nurhayati Nursidik Yulianto Nursidik Yulianto, Nursidik Oudrey Addriana Paramita, Diajeng Putri Putri, Syakirah Yasmin Ramdani, Dewi Rippi Maya Riyaningrum, Wahyu Rusita, Resi Sambudi, Nonny Soraya Samlan, Karima Santosa, Nadya Rachmania Sari, Dewi Lintang Shiddiq, Muhandis Sholihattri, Wina Sholika Sari, Trisiyana Sigit Wibawanto, Sigit Siti Fatimah Soewoto, Haswi Purwandanu SRY WAHYUNI, SRY Suaebah, Evi Sudjarwo, SA Sudrajat, Aji Ajat Sugiarto, Iyon Titok Sukmawati, Rosnanda Sulaeman, Uyi Suryadi Suryadi Suryadini, Aisha Suci Sutarno Sutarno Talitha Nabilla Wijayanata Taufik Taufik Tejo Faridh Waloyo Tiam, Tan Swee Tiana, Elia Marta Triyono, Djoko Tulus Ikhsan Nasution Tutiek Purwanti Umi Aida Rohma Utami, Mega Putri Nur Wahyudi Wahyudi Wahyudi, Muh.Diki Wijoyo, Hadi Wildan Panji Tresna Wiwied Ekasari Yin, Shu Yuliati Herbani ZAINUL ARIFIN IMAM SUPARDI Zaskya Wati, Wa Ode Zulfa Diana Zulfiana, Risa