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All Journal International Journal of Evaluation and Research in Education (IJERE) Jurnal Pendidikan Indonesia Alchemy : Journal of Chemistry Tadris: Jurnal keguruan dan Ilmu Tarbiyah Jurnal Inovasi Pendidikan IPA EduChemia: Jurnal Kimia dan Pendidikan Biopropal Industri Warta IHP (Warta Industri Hasil Pertanian) Jurnal Tadris Kimiya Indonesian Journal of Science and Education Journal of Science Innovare Komputasi: Jurnal Ilmiah Ilmu Komputer dan Matematika Al-Ta'lim Jurnal EDUCATIO: Jurnal Pendidikan Indonesia Jurnal ABDINUS : Jurnal Pengabdian Nusantara JPPS (Jurnal Penelitian Pendidikan Sains) Journal of Innovation in Educational and Cultural Research International Journal of Research in Community Services International Journal of STEM Education for Sustainability JSEP (Journal of Science Education and Practice) Helium: Journal of Science and Applied Chemistry Jurnal Pemberdayaan Masyarakat Jurnal Pendidikan Sains Indonesia (Indonesian Journal of Science Education) JIPI (Jurnal IPA dan Pembelajaran IPA) Kenduri: Jurnal Pengabdian Dan Pemberdayaan Masyarakat Journal of Environment and Sustainability Education Jurnal Pengabdian Isola ABDIMAS Iqtishadia IJIS Edu : Indonesian Journal of Integrated Science Education

Leny Heliawati

Universitas Pakuan

Author-ID : 2525586

Religion Agriculture, Biological Sciences & Forestry Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Economics, Econometrics & Finance Education Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Medicine & Pharmacology Physics Social Sciences Other

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DEVELOPMENT OF COD (CHEMICAL OXYGEN DEMAND) ANALYSIS METHOD IN WASTE WATER USING SPECTRODIRECT Ade Heri Mulyati; Leny Heliawati; Sutanto .; Uswatun Hasanah; Diana Widiastuti; Siti Warnasih; Yulian Syahputri
Journal of Science Innovare Vol 3, No 2 (2020): Journal of Science Innovare, Volume 03 Number 02 2020
Publisher : Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/jsi.v3i2.3006

Increased human activities will cause various problems, one of which is water pollution in water sources because it receives a pollution load that exceeds its carrying capacity. In the context of environmental conservation, the government has set quality standards for liquid waste produced by various industries and other activities in a Decree of the State Minister for the Environment. COD (Chemical Oxygen Demand) is one of the most important parameters in wastewater quality standards. This study aims to validate the COD analysis method which refers to COD Thermoreactor System (LOVIBOND brand) at Pakuan University Service Laboratory, to ensure the validity of COD analysis results at Pakuan University Service Laboratory. Spectrodirect COD analysis method provides results that meet the requirements of accuracy, precision, LOD, and LOQ which is quite good. The results of the Coefficient of Variation give good results with a value of 1.8841% indicating the accuracy of the analysis method is good. The accuracy parameter also gives good results and meets the requirements with a% recovery value of 98.70351%. Overall, it can be stated that the spectrodirect analysis method tested is an accurate, precise, simple, and economical method for determining COD levels

Characteristics of Chemistry Teaching Material Voltaic Cells on Students’ Creativity and Concept Mastery Giyanto Giyanto; Bibin Rubini; Leny Heliawati
Jurnal Pendidikan Sains Indonesia Vol 8, No 2 (2020): OKTOBER 2020
Publisher : Universitas Syiah Kuala

This study aims to find the characteristics of chemistry teaching material used by 16 teachers on the concept of voltaic cells in vocational high schools. The characteristics of teaching material accommodate 21st-century learning which includes the accuracy of the contents, the accuracy of the scope, the updating of the material, the comprehensibility of the text, the use of the language, and the use of the illustrations. The research identifies student competency profiles that are indispensable in 21st-century learning, namely creativity and concept mastery. The subject of the research is teaching material used by 16 chemistry teachers in 16 vocational high schools with 95 students studied. Data were collected using observation sheets, product creativity questionnaires, and tests of students' concept mastery. The data obtained were analyzed using a quantitative descriptive method. The results show that the teaching materials used in learning had not used an approach that encouraged creativity and learning outcomes for students. This resulted in low creative-thinking ability at a rate of 27.03% and in low mastery concept showed from the mean of learning outcomes at a score of 22.4 from a maximum score of 100. The study concludes that the characteristics of chemistry teaching material voltaic cells are not under the demands of the characteristics of 21st-century learning in the aspect of the content.

The Effectiveness of Online Learning in Solubility and Solubility Product Constant Materials on Students’ Analytical Thinking Skills Leny Heliawati*; Uun Sundari; Anna Permanasari
Jurnal Pendidikan Sains Indonesia Vol 9, No 4 (2021): OCTOBER 2021
Publisher : Universitas Syiah Kuala

Analytical thinking skill is a part of higher order thinking skills. The ability to think analytically is very important for students who want to help solve problems and make decisions that can be applied in learning and life. This study aims to determine the improvement of students’ analytical thinking skills on the material solubility and solubility product which is carried out in online learning during the Covid-19 pandemic. This study uses a pre-experimental design, with the model The One Group Pretest – Posttest. The population of this study was students of class XI IPA SMAIT Insantama Bogor in the even semester of the 2019/2020 school year. The data were collected by using the thinking instrument skill test which was used in the form of an analytical thinking ability essay covering 3 indicators: distinguishing, organizing, and attributing. The results showed the dominance of students’ analytical thinking skills at the beginning of the period with the average majority (44%), and after treatment, increased in the very good category (74%). The N-gain score for the results of increasing students’ thinking skills is 0.70, which is in the high category. This study concludes that online learning in the material of solubility and solubility results proved to be effective in improving students’ analytical thinking skills during the pandemic

Identification of Antibacterial Compounds from Endophytic Bacterial Extract of Green Grass Cincau Plant (Premna oblongifolia Merr) Anna Muthia Soliha; Leny Heliawati; Siti Warnasih
Helium: Journal of Science and Applied Chemistry Vol 1, No 2 (2021): Helium: Journal of Science and Applied Chemistry
Publisher : Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/helium.v1i2.4538

Green grass jelly (Premna oblongifolia Merr) is a plant that belongs to the Verbenaceae family with the Premna genus. The genus Premna has about 200 species in the Verbenaceae family which are spread in tropical to subtropical areas such as Asia, Africa, and Australia. This plant has potential as antibacterial, antipyretic, anti-inflammatory, and antioxidant. This research was conducted to make an extract of endophytic bacteria obtained from green grass jelly plants by maceration method. The extract obtained was tested for its antibacterial activity by disc diffusion method. Extracts with the highest antibacterial activity were identified by FTIR and GCMS. The results showed that the methanol extract of endophytic bacteria of green grass jelly plants had broad spectrum antibacterial activity because it was able to inhibit the growth of Gram-positive bacteria (Bacillus subtilis) and Gram-negative bacteria (Pseudomonas aeruginosa). The results of FTIR and GCMS showed that the active compounds contained in the endophytic bacteria of green grass jelly plants were thought to be Nerolidol compounds or 3,7,11-trimethyl-1,6,10-dokatrien-3-ol which are secondary metabolites of the sesquiterpene alcohol group and play a role in as an antibacterial.

Optimization of The Addition Of Polivinil Alcohol (PVA) as A Plasticizer In Biofilm with Tapioca-Chitosan Flour Material Tri Aminingsih; Leny Heliawati; Muhammad Fathurrahman
Helium: Journal of Science and Applied Chemistry Vol 1, No 1 (2021): Helium: Journal of Science and Applied Chemistry
Publisher : Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/helium.v1i1.2954

The addition of a plasticizer, namely polyvinyl alcohol (PVA) as a plasticizer, will increase flexibility and prevent the polymer from cracking. The purpose of this study was to compare the mechanical properties of biofilms from tapioca-chitosan flour with or without the addition of polyvinyl alcohol (PVA) and determine the mass of polyvinyl alcohol (PVA) which can provide optimum mechanical properties of biofilms, test the biodegradability of biofilms and polypropylene plastics and to analyze biofilms using FT-IR. The making of biofilm from 4% tapioca flour and 2% chitosan was carried out by adding variations of polyvinyl alcohol as much as 0, 1, 2, 3, 4 and 5 grams to each tapioca-chitosan flour solution. The effect of adding polyvinyl alcohol (PVA) can be seen from the results of the tensile strength test, the breaking length test, the water resistance test and the biodegradability test. The resulting biofilm functional group analysis was performed by FT-IR. The results showed that the addition of PVA could increase the tensile strength and breaking length, but decreased the water resistance of the biofilm. The optimum mechanical properties of tapioca-chitosan flour biofilm resulted from the addition of 3 grams of PVA with a tensile strength of 2.163 kgf / cm2, the breaking length of 13.64% and 12.46% of absorbed water. Biofilms can be degraded by the fungus Aspergilus niger. The results of biofilm analysis using FTIR indicate the presence of functional groups (CH, NH2, NH, OH, CO and CN) which are the functional groups of the biofilm constituent materials. The optimum mechanical properties of tapioca-chitosan flour biofilm resulted from the addition of 3 grams of PVA with a tensile strength of 2.163 kgf / cm2, the breaking length of 13.64% and 12.46% of absorbed water. Biofilms can be degraded by the fungus Aspergilus niger. The results of biofilm analysis using FT-IR indicate the presence of functional groups (CH, NH2, NH, OH, CO and CN) which are the functional groups of the biofilm constituent materials.

Students' Perceptions of the Internalization of Islamic Values in Buffer Solution Teaching Materials Uun Sundari; Leny Heliawati*; Anna Permanasari
JIPI (Jurnal IPA dan Pembelajaran IPA) Vol 4, No 2 (2020): DECEMBER 2020
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jipi.v4i2.16730

Learning that has a divine value has an important role in preparing a generation of higher quality, who masters science and technology with good morals. This study aims to analyze students' perceptions of chemistry teaching materials on buffer solution material with Islamic internalization values. This study compares students' perceptions of teaching materials that have been used with teaching materials internalized with Islamic values. The perception of the Islamic value in this study was measured by analyzing the motivation, use, and belief of the buffer solution teaching material that integrates Islamic values. This type of research is ex post facto research by collecting data directly to respondents through questionnaires, interviews, and observations. The data analysis technique was done by descriptive qualitative method. This research conducted on 50 eleventh dan twelfth-grade students. The target analysis of these needs is focused on students studying in Islamic-based schools. The results showed that the number of students in the category of “highly need teaching materials with Islamic internalization” was 36 people (72%), 14 people are in “need” category (28%), and no one was of the view that teaching materials with Islamic internalization were not needed. From this study, we can conclude that students in Islamic-based schools have good perceptions and need buffer solution teaching material with Islamic internalization values

VARK-based Chemistry Learning to Improve Studentsâ€™ Critical Thinking Skills in Learning Molecular Geometry Ade Gunawan; Leny Heliawati; Anna Permanasari
Journal of Innovation in Educational and Cultural Research Vol 4, No 4 (2023)
Publisher : Yayasan Keluarga Guru Mandiri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.46843/jiecr.v4i4.737

Learning that does not accommodate the learning styles of all students will experience boredom and a decrease in the critical level of students. This study aims to determine the effect of VARK learning style-based chemistry learning on improving students' critical thinking skills. The study used a quantitative method with a pre-experimental design and one group pretest-posttest design. The research was conducted on 65 students of the State Islamic Senior High School in Bogor. The instrument used was an essay test of ten questions that met the criteria for critical thinking indicators. The instrument trials used were validity and reliability tests. Next, the Paired T-Test and N-Gain Tests were carried out. Based on the Paired T-Test, a significance value of 0.00 was obtained, indicating that Ho was rejected, so there were differences in students' critical thinking skills before and after the VARK-based chemistry learning was implemented. The results of the N-Gain test increased students' critical thinking skills on average by 0.68 in the moderate category. This study concludes that VARK-based chemistry learning on molecular geometry material can improve students' critical thinking skills.Â Â

Message Encryption in Digital Images using the Zhang LSB Imange Method Saepulrohman, Asep; Ismangil, Agus; Heliawati, Leny
Komputasi: Jurnal Ilmiah Ilmu Komputer dan Matematika Vol 21, No 1 (2024): Komputasi: Jurnal Ilmiah Ilmu Komputer dan Matematika
Publisher : Ilmu Komputer, FMIPA, Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/komputasi.v21i1.9314

Message encryption in digital images using the Zhang LSB Image method is a steganography technique that utilizes the Least Significant Bit (LSB) method to hide secret messages in the last bit of the image pixel. This method allows the use of images as a medium to convey hidden messages. The encryption process involves two main stages, namely message encryption and message hiding in an image. Message encryption is carried out using strong cryptographic algorithms to secure the authenticity and confidentiality of messages. Then, the encrypted message is inserted into the last bit of the image pixel using the LSB method. This is done by modifying the last bit value of the pixel so that the change is not visually visible to the human eye. To recover the original message, the message recovery process involves extracting the last bit of the modified image pixel and decrypting the message using the appropriate key. The Zhang LSB Image method is a steganography technique that is relatively simple but effective in hiding messages in digital images.

Effectiveness of Deep Phet Interactive Simulation Improving Understanding of The Concept of Material Change Gunawan, Ade; Heliawati, Leny; Permanasari, Anna
JOURNAL OF SCIENCE EDUCATION AND PRACTICE Vol 7, No 2 (2023): December 2023
Publisher : Universitas Pakuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33751/jsep.v7i2.9213

The rapid development of technology demands optimal use in the education sector in order to achieve sustainable progress. Integrating technology in the learning process, especially through the application of interactive simulations, not only provides clear visual representations of scientific concepts, but also increases student involvement in learning, stimulates curiosity, and supports the formation of deeper understanding. One platform that stands out in this regard is Physics Education Technology (PhET), which provides realistic and easy-to-use simulations. Through PhET, students can conduct virtual experiments and immediately see the results. This research aims to evaluate the effectiveness of using PhET interactive simulations in increasing students' understanding of the concept of chemical material changes, by applying a learning model Discovery Learning. The research method applied is quantitative with a quasi-experimental design Nonequivalent Control Group Design, involving two groups of class 10 students at Madrasah Aliyah Bogor Regency. Analysis results Paired T-Test in the experimental group showed a score of 0.000 smaller than 0.05, indicating a significant difference between the pretest and posttest scores. This illustrates the positive impact of using PhET simulations on improving student understanding. The results of the N-Gain analysis show an average value of 0.5, indicating that PhET's effectiveness in improving students' understanding has moderate criteria. Further evaluation is needed to understand the factors that influence the effectiveness of PhET in this learning context.

Workshop on Making Teaching Materials and Lesson Plan Based on Potential and Local Wisdom for Science Teachers [Workshop Pembuatan Bahan Ajar dan RPP Berbasis Potensi dan Kearifan Lokal bagi Guru IPA] Misbah, Misbah; Kadarohman, Asep; Sinaga, Parlindungan; Yuliani, Galuh; Anwar, Sjaeful; Rosbiono, Momo; Winarno, Nanang; Prasetyorini, Prasetyorini; Heliawati, Leny; Unwakoly, Semuel; Utami, Indri Sari; Salam, Abduh; Kerans, Geterudis; Karimah, Fani Ulya; Warliyah, Heli
Jurnal Pengabdian Isola Vol 2, No 1 (2023): JPI: VOLUME 2, ISSUE 1, 2023
Publisher : Universitas Pendidikan Indonesia (UPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/jpi.v2i1.57605

Integrasi potensi dan kearifan lokal ke dalam pembelajaran IPA membuat pembelajaran lebih bermakna serta dapat menanamkan nilai-nilai kearifan lokal. Namun, faktanya masih banyak guru yang mengalami kesulitan dalam mengintegrasikan potensi dan kearifan lokal, sehingga perlu dilakukan kegiatan Pengabdian kepada Masyarakat (PkM) yang bertujuan untuk meningkatkan pemahaman guru dalam mengimplementasikan potensi dan kearifan lokal ke dalam pembelajaran IPA. Metode dalam kegiatan PkM ini adalah workshop yang dilaksanakan secara online melalui Zoom meeting pada tanggal 1216 Juli 2022. Kegiatan diikuti oleh 78 guru IPA di seluruh Indonesia. Data pemahaman guru diperoleh melalui angket yang dibagikan sebelum dan sesudah workshop dilaksanakan. Secara umum pemahaman peserta workshop mengalami peningkatan antara sebelum dan sesudah workshop diselenggarakan. Selain itu evaluasi penyelenggaraan PkM yang diberikan oleh peserta secara umum berada pada kategori baik dan sangat baik. Dengan demikian disimpulkan bahwa melalui kegiatan workshop ini dapat meningkatkan pemahaman guru IPA dalam membuat bahan ajar berbasis potensi dan kearifan lokal.The integration of local potential and wisdom into science learning makes learning more meaningful and can instil local wisdom values. However, the fact is that there are still many teachers who experience difficulties in integrating local potential and wisdom, so it is necessary to carry out community service activities which aim to increase teacher understanding in implementing local potential and wisdom into science learning. The method in this community service activity is a workshop held online via Zoom meeting on 12 16 July 2022. 78 science teachers throughout Indonesia attended the activity. Teacher understanding data was obtained through questionnaires which were distributed before and after the workshop was held. In general, workshop participants' understanding increased between before and after the workshop was held. In addition, the participants' evaluation of the community service implementation was generally in the good and very good categories. Thus it was concluded that this workshop activity could increase science teachers' understanding in making teaching materials based on local potential and wisdom.

Co-Authors Ade Gunawan Ade Gunawan Ade Heri Mulyati Ade Heri Mulyati, Ade Heri Adinda Adriansyah, Putri Nabila Adriansyah, Putri Nabila Adinda Afakillah, I.Ibnu Agus Ismangil Anna Muthia Soliha Anna Permanasari Arifah, Laila Asep Kadarohman Asep Saepulrohman Bibin Rubini Bustanussalam Bustanussalam Carlina Anggraeni Dadang Jaenudin Diana Widiastuti Didit Ardianto Didit Ardianto Dwi Pursitasari, Indarini Eka Herlina Elvi Kurniasih Elvi Kurniasih Eris Septiana Farida Nuraeni Fauzia Nurul Izzati Fauziah, Zahra Nur Fauzy Rachman Fenny Pebriani Fenny Pebriani Firmayanto, Rudi Giyanto Giyanto Harianto, Bibit Henrikus Suparjono Herlina Herlina I. Dwi Pursitasari I.Ibnu Afakillah Indang Dwi Rahayu Indarini Dwi Pursitasari Juliatriyani Juliatriyani Kabir, Abyan Jausan Karimah, Fani Ulya kerans, geterudis Khoiriyah, Ainun Kurniasih, Septi Kurniasih, Surti Layung Paramesti Martha Lidiawati, Linda Linda Jati Kusumawardani Linda Lidiawati Linda Lidiawati Linda lidiawati M Zainal Arifin, M Zainal Mahrun Mahrun Mahrun Mahrun, Mahrun Makmuri Makmuri Melani Nurastuti Misbah Misbah Momo Rosbiono Mr Sjaeful Anwar Muhammad Fathurrahman Muhammad Fathurrahman Mulyani, Pangastuti Sri Nabila Adinda Adriansyah, Putri Nanang Winarno Niken Oktaviani Nulhakim, Lukman Parlindungan Sinaga Partomuan Simanjuntak Pebriani, Fenny Prasetyorini Prasetyorini Pursitasari, I. Dwi Rahmawati, Siti Irma Ramadhan, Muhamad Farhan Rd. Nia Elisa Yulianti Rienoviar, - Rita Retnowati Rudi Firmayanto Salam, Abduh Semuel Unwakoly Siti Fatimah Siti Warnasih Sundari, Tri Surti Kurniasih Sutanto . Syamsiah Syamsiah Taufik, Annisa Novianti Tri Aminingsih Tri Aminingsih Tri Sundari Uswatun Hasanah Utami, Indri Sari Uun Sundari Uun Sundari Uun Sundari Warliyah, Heli Wien Kusharyoto Yatri Hapsari Yudhie Suchyadi Yulian Syahputri Yuliani, Galuh Zulnaidi, Hutkemri

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