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Pemanfaatan Serat Daun Nanas Dalam Sintesis Geopolimer Berbasis Abu Layang Batubara Hisan, Aisyah Khoirotun; Kusumastuti, Ella; Mahatmanti, Widhi
Indonesian Journal of Chemical Science Vol 6 No 2 (2017)
Publisher : Indonesian Journal of Chemical Science

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Abstract

Sintesis geopolimer dengan penambahan serat daun nanas telah dilakukan. Sintesis dilakukan dengan mencampurkan abu layang, NaOH, dan Na2SiO3 pada rasio SiO2/Al2O3 5,29 mol, kemudian ditambahkan serat daun nanas dengan variasi 0-2,5% (b/b). Penambahan serat optimum terjadi pada 1,5% (b/b) dengan kuat tekan 41,91 MPa dan kuat tarik belah 16,28 MPa. Sampel uji geopolimer dengan penambahan serat 1,5% memiliki fasa amorf yang relatif lebih besar jika dibandingkan dengan sampel uji 0 dan 2,5% serat. Analisis gugus fungsi geopolimer dengan FT-IR (Fourier Transform Infrared) menunjukkan adanya gugus CH pada 2924,09 cm-1. Analisis morfologi menggunakan SEM (Scanning Electron Microscopy) menunjukkan bahwa morfologi terlihat lebih homogen dan terdapat partikel serat yang berada di antara matriks geopolimer.Geopolymer synthesis with the addition of pineapple leaf fibers have been done. Synthesis is done by mixing fly ash, NaOH, and Na2SiO3 at a ratio of SiO2/Al2O3 5.29 mol, then add pineapple leaf fibers with variations from 0 to 2.5% (w/w). The addition of optimum fiber occurred in 1.5% (w/w) with a compressive strength of 41.91 MPa and 16.28 MPa tensile strength sides. Geopolymer test samples with addition of 1.5% fibers have an amorphous phase is relatively large when compared to the test sample 0 and 2.5% fiber. Chemical bonds analysis of geopolymer by FT-IR (Fourier Transform Infrared) showed that bond CH at 2924.09 cm-1. Morphology analysis using SEM (Scanning Electron Microscopy) showed that the morphology looks more homogeneous and there is a fiber particles that are among the geopolymer matrix.
Efektivitas Lembar Kerja Siswa Bermuatan Etnosains Materi Hidrolisis Garam untuk Meningkatkan Literasi Sains Siswa SMA Ariningtyas, Agnes; Wardani, Sri; Mahatmanti, Widhi
Journal of Innovative Science Education Vol 6 No 2 (2017)
Publisher : Postgraduate, Universitas Negeri Semarang, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (503.326 KB) | DOI: 10.15294/jise.v6i2.19718

Abstract

Pembelajaran sains dikelas hendaknya menuntun siswa untuk melek tentang ilmu pengetahuan dan teknologi Kegiatan pembelajaran seharusnya memanfaatkan secara optimal potensi lingkungan supaya pembelajaran lebih bermakna namun pada kenyataannya hal ini belum selalu dilakukan oleh guru. Penelitian ini bertujuan untuk mengembangkan LKS bermuatan etnosains materi hidrolisis garam untuk meningkatkan literasi sains siswa SMA. Penelitian ini merupakan penelitian pengembangan atau Researchand Development (R&D). Desain penelitian yang digunakan adalah pretest and post test control group design. Data penelitian diperoleh dengan metode wawancara, observasi, dokumentasi, angket, dan tes. Hasil penelitian menunjukkan bahwa LKS bermuatan etnosains untuk meningkatkan literasi sains pada materi hidrolisis garam yang dikembangkan dapat meningkatkan aspek konten siswa pada kelas eksperimen dengan perolehan N-Gain sebesar 0,71 dalam kategori tinggi, aspek konteks siswa dengan perolehan N-Gain sebesar 0,73 dalam kategori tinggi dan aspek proses sains siswa dengan perolehan N-Gain sebesar 0,50 dalam kategori sedang, dan siswa memberikan respon positif terhadap implementasi LKS bermuatan etnosains materi hidrolisis garam yang dikembangkan dalam kategori baik atau sebesar 77,67%. The process of learning science in the classroom should lead students to literate about science and technology. Learning activities should utilize optimally potential environment, especially the local culture so that the learning more meaningful but in reality this has not always done by the teacher. This research aims to develop is LKS as etnosains-laden material hydrolysis of salt to enhance the literacy of science high school students.This research is the development of research or Researchand Development (R & D).The Research Design used was a pretest and post test control group design. Research data obtained by the method of interview, observation, documentation, the now, and test. The results showed that etnosains charge is LKS to improve science literacy on the material the hydrolysis of salt has developed increase the content aspect of the students in class experiments with the acquisition of N-Gain of 0.71 in high context aspect category of students with obtaining N-Gain amounted to 0.73 in a high category and aspects of the process of science students with obtaining N-Gain of 0.50 in that category are , and the students gave positive response towards implementation is LKS as a charged etnosains salts are developed in the category of good or of 77.67%.
The Development of The Chemical Teaching Material Integrated to Nautical Material to Improve Understanding The Hydrocarbon and Petroleum Concept in The Shipping Vocational High School Ariyani, Nigita; Susilaningsih, Endang; Mahatmanti, Widhi
Journal of Innovative Science Education Vol 7 No 2 (2018)
Publisher : Postgraduate, Universitas Negeri Semarang, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (818.635 KB) | DOI: 10.15294/jise.v7i2.28426

Abstract

This research is development research aimed at producing chemically integrated teaching materials for commercial nautical vessels. The nautical vocational material for commercial vessels. namely ship machinery on the subject of the types of fuels and lubricants. is integrated into the subject matter of hydrocarbons and petroleum. In the subject matter of hydrocarbons and petroleum. vocational awareness of the environment and pollution prevention are also integrated. The study began with 4 stages. the phase define starts with identifying the needs of teaching materials in vocational voyage. at the stage design is made of teaching materials by integrating the two material vocational nautical commercial ships. stages develop are used to enhance the results of the phase design to validate and test of materials teach Validation used at this stage includes expert validation. readability and assessment. and trials to determine the response of students. The results of the study show that integrated chemistry teaching materials are very suitable to be used in chemical learning at the Vocational High School of Nautical. Based on the results of the analysis obtained a validity value of 3.72 (93%) with a very good category. for 94% of students showed a positive response to integrated chemistry teaching materials. The data obtained from the concept of understanding obtained tcount= 19.59> t0.05. 32= 1.699 in learning using integrated chemistry teaching materials showing an increase in understanding of concepts. The final stage of this research is the stage disseminate by publishing through journals and implementing teaching materials in schools.
MEMBRAN PADAT KITOSAN-SILIKA-PEG SEBAGAI MEMBRAN PEMISAH ION LOGAM BIVALEN DAN RHODAMIN B PADA LIMBAH CAIR INDUSTRI TEKSTIL Mahatmanti, Widhi; Kusumastuti, Ella; Pita Rengga, Wara Dyah
JC-T (Journal Cis-Trans): Jurnal Kimia dan Terapannya Vol 3, No 2 (2019)
Publisher : State University of Malang or Universitas Negeri Malang (UM)

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Abstract

Penggunaan membran padat kitosan-silika-polietilen glikol (Ch/Si/P) sebagai membran pemisah telah dipelajari. Dalam penelitian ini, membran padat kitosan-silika-polietilen glikol digunakan sebagai membran pemisah untuk ion logam bivalen, termasuk Pb(II), Cu(II), Cd II), dan zat warna Rhodamin B dalam limbah cair tekstil. Membran padat Ch/Si/P dibuat dengan mencampurkan kitosan, silika (dengan natrium silikat yang diisolasi dari abu sekam padi sebagai sumber silika) dan polietilen glikol dengan perbandingan 1: 0,8: 0,5 (b/b). Uji kinerja membran padat dilakukan menggunakan metode dead-end. Uji kinerja menunjukkan bahwa selektivitas membran padat Ch/Si/P meningkat dari Cu(II)> Cd(II)> Pb(II)> Rhodamine B. Membran komersial menunjukkan, selektivitas mengikuti urutan Rhodamine B> Pb(II)> Cd(II)> Cu(II). Hasil penelitian menunjukkan  bahwa membran padat Ch/Si/P lebih baik sebagai membran pemisah ion logam bivalen dibandingkan membran komersial. Membran komersial lebih baik sebagai membran pemisah Rhodamine B  dibandingkan membran padat Ch/Si/P karena memiliki struktur berserat dan berpori.