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All Journal Rekayasa: Jurnal Penerapan Teknologi dan Pembelajaran Indonesian Journal of Chemical Science JMM (Jurnal Masyarakat Mandiri) Journal of Innovative Science Education
Widhi Mahatmanti
Jurusan Kimia Fakultas MIPA Universitas Negeri Semarang
Chemical Engineering, Chemistry & Bioengineering Chemistry Education Engineering Other

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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

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

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.
PEMBUATAN PUPUK FERMENTASI CAIR BERBASIS LIMBAH VINASSE Astuti, Widi; Mahatmanti, Widhi
Rekayasa : Jurnal Penerapan Teknologi dan Pembelajaran Vol 15, No 1 (2017): Juli 2017
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/rekayasa.v15i1.12579

Abstract

Vinasse waste, which is a by-product of the alcohol industry, has polluted the rice field en- vironment in the Bekonang, Sukoharjo and surrounding villages. This problem arises into the realm of law with the publication of a law on alcohol which prohibits low-level alcohol producers to sell to the public. This regulation increasingly discourages alcoholic craftsmen who are mostly used as raw materials in herbal and medicinal industries. In addition to the narrower marketing, they are also confronted by farmers who are angered by the environmental pollution of vinasse waste that for decades has only been dumped into irrigation flows without treatment. Field observations and preliminary studies on vinasse waste content found no harmful ingredients to the environment ex- cept high acidity (4.5). The rest is the content of organic materials that can be utilized to fertilize the soil. Therefore waste alcohol should be processed with the addition of complementary organic materials to be used as a medium to grow probiotic bacteria that are very good for soil and plants. This activity is intended to provide education on how to process waste vinasse into liquid fermen- tation  fertilizer  that  can  be  utilized  by  local  residents  and  society  in  general.  Activity  method that will be done is socialization about potential waste vinasse, making waste processing equip- ment,  giving  skill  to  make  liquid  fermentation  fertilizer  and  applying  it  to  cassava  plant  land. These  activities  are  expected  to  generate  positive  perception  changes  and  increase  knowl- edge of craftsmen and farmers in addressing vinasse waste issues. In addition, both parties are able  to  treat  the  harmful  waste  into  probiotic  bacteria  and  fertilizer  products  with  high  qual- ity. With this activity, the source of conflict of Bekonang village community will decrease slow- ly along with the socialization of the results of the activity to the wider community and the as- sistance  of  the  village  government  as  the  administrative  responsibility  of  Bekonang  village
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 : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v6i2.12272

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.
PEMBUATAN PUPUK FERMENTASI CAIR BERBASIS LIMBAH VINASSE Astuti, Widi; Mahatmanti, Widhi
Rekayasa : Jurnal Penerapan Teknologi dan Pembelajaran Vol 15, No 1 (2017): Juli 2017
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/rekayasa.v15i1.12579

Abstract

Vinasse waste, which is a by-product of the alcohol industry, has polluted the rice field en- vironment in the Bekonang, Sukoharjo and surrounding villages. This problem arises into the realm of law with the publication of a law on alcohol which prohibits low-level alcohol producers to sell to the public. This regulation increasingly discourages alcoholic craftsmen who are mostly used as raw materials in herbal and medicinal industries. In addition to the narrower marketing, they are also confronted by farmers who are angered by the environmental pollution of vinasse waste that for decades has only been dumped into irrigation flows without treatment. Field observations and preliminary studies on vinasse waste content found no harmful ingredients to the environment ex- cept high acidity (4.5). The rest is the content of organic materials that can be utilized to fertilize the soil. Therefore waste alcohol should be processed with the addition of complementary organic materials to be used as a medium to grow probiotic bacteria that are very good for soil and plants. This activity is intended to provide education on how to process waste vinasse into liquid fermen- tation  fertilizer  that  can  be  utilized  by  local  residents  and  society  in  general.  Activity  method that will be done is socialization about potential waste vinasse, making waste processing equip- ment,  giving  skill  to  make  liquid  fermentation  fertilizer  and  applying  it  to  cassava  plant  land. These  activities  are  expected  to  generate  positive  perception  changes  and  increase  knowl- edge of craftsmen and farmers in addressing vinasse waste issues. In addition, both parties are able  to  treat  the  harmful  waste  into  probiotic  bacteria  and  fertilizer  products  with  high  qual- ity. With this activity, the source of conflict of Bekonang village community will decrease slow- ly along with the socialization of the results of the activity to the wider community and the as- sistance  of  the  village  government  as  the  administrative  responsibility  of  Bekonang  village
INOVASI TUNGKU MASAKAN HEMAT ENERGI PADA INDUSTRI TAHU Handayani, Prima Astuti; Mahatmanti, Widhi; Musyono, Ari Dwi Nur Indriawan; Mursit, R. Ambar Kuntoro; Wikandaru, Achmad; Pikrihaikal, Tedhy; Sawiji, Kurnia Ayu
JMM (Jurnal Masyarakat Mandiri) Vol 9, No 6 (2025): Desember
Publisher : Universitas Muhammadiyah Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31764/jmm.v9i6.35581

Abstract

Abstrak: UKM Tahu Ngaran merupakan industri rumah tangga yang produktif secara ekonomi. Mitra diketuai oleh pak Muhtadi yang beranggotan 7 orang yang berlokasi di Kecamatan Gunungpati Semarang. Setiap harinya Tahu Ngaran mampu produksi 11-13 kali proses produksi tahu. Permasalahan yang dihadapi mitra yaitu tungku masakan belum menggunakan teknologi dan mitra belum melakukan branding produk dan pengemasan produk tahu. Tujuan dari kegiatan PKM untuk meningkatkan efisiensi energi dan produktivitas UKM Tahu Ngaran, sehingga dapat meningkatkan kesejahteraan mitra. Untuk mencapai tujuan kegiatan maka metode yang dilakukan meliputi sosialisasi, praktek, pendampingan dan evaluasi. Evaluasi dilakukan melalui tanya jawab secara langsung kepada mitra dan pengamatan saat kegiatan berlangsung. Setelah kegiatan program selesai tim akan melakukan pemantauan akan keberlangsungan program di lokasi mitra. Hasil PkM diperoleh tungku masakan yang memberikan hemat waktu perebusan 33,33% dan penghematan kayu bakar 33,33%. Dengan demikian mitra dapat meningkatkan laba sebesar 67,26% sehingga dapat meningkatkan kesejahteraan UKM Tahu Ngaran. Produk Tahu Ngaran sudah dipasarkan berkemasan dengan nama brand “Tahu Ngaran”.Abstract: UKM Tahu Ngaran is an economically productive home industry. The partner organization, led by Mr. Muhtadi, consists of 7 members and is in Gunungpati District, Semarang. Daily production at Tahu Ngaran involves 11 to 13 batches of tofu processing. The primary challenges faced by the partner included the use of non-technological cooking stoves and a lack of product branding and packaging. The objective of this Community Partnership Program (PKM) activity was to enhance energy efficiency and productivity for UKM Tahu Ngaran, thereby improving the welfare of the partners. To achieve this objective, the methodology employed involved a series of steps: socialization, practical training, mentorship, and evaluation. The evaluation was conducted through direct interviews (Q&A) with the partners and observational monitoring during the activity. Upon completion of the program, the team will continue to monitor the sustainability of the program at the partner's location. The results of the PKM included the implementation of a new cooking stove, which yielded a 33.33% reduction in boiling time and a 33.33% saving in firewood consumption. Consequently, the partner was able to increase profit by 67.26%, successfully improving the welfare of UKM Tahu Ngaran. The Tahu Ngaran product is now marketed in branded packaging under the name "Tahu Ngaran".
Co-Authors Ariningtyas, Agnes Ariyani, Nigita Ella Kusumastuti, Ella Endang Susilaningsih Hisan, Aisyah Khoirotun Hisan, Aisyah Khoirotun Mursit, R. Ambar Kuntoro Musyono, Ari Dwi Nur Indriawan Pikrihaikal, Tedhy Prima Astuti Handayani Sawiji, Kurnia Ayu SRI WARDANI Widi Astuti Wikandaru, Achmad