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Synthesis of SrO.SiO2 Catalyst and Its Application in the Transesterification Reactions of Soybean Oil Nuni Widiarti; Lisa Amalia Suryana; Nanik Wijayati; Endah Fitriani Rahayu; Harjito Harjito; Samuel Budi Wardhana; Didik Prasetyoko; Suprapto Suprapto
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 2 Year 2017 (August 2017)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.12.2.804.299-305

Abstract

The synthesis and characterization of SrO.SiO2 were carried out. The rice hull ash was utilized as a source for SiO2. The SrO.SiO2 was prepared by sol-gel technique, and the ratios of SrO:SiO2 were      varied as 0:1, 1:0, 3:2, 2:4, and 2:7. The sol-gel was calcined at 800 oC for 4 hours. The result was    characterized using XRD and FTIR. The diffraction pattern shows that the diffraction angle was shifted, and the intensity of the main peaks was increased. This research indicated that the            crystallinity of SrO was improved at the higher SiO content. Further, a new peak was observed in the IR spectra at a wavenumber of 900 cm-1 indicating the appearance of new functional groups of the SrO.SiO2. The catalytic activity of SrO.SiO2 on transesterification reaction was optimized. The optimum condition was obtained at SrO.SiO2 of 2:7, reaction time of 30 minutes, reaction temperature of 65 oC, the amount of catalyst of 1 % w/v of reactants, and the biodiesel yield of 96.66 %. 
The Influence of Project Based Learning Model on Students' Problem-Solving Competence in Learning of Acid-Base Faizah, Nur; Wijayati, Nanik; Widiatningrum, Talitha
Journal of Innovative Science Education Vol 11 No 3 (2022): Special Issue
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jise.v11i1.56478

Abstract

The study aims to determine the influence of Project Based Learning Model on students' problem-solving competency. The method used was experimental method with Pretest-Posttest Control Group Design. This study was conducted at the State Junior High School 2 Brebes with the students of grade VII in the academic year 2021/2022 as the research population. The sampling technique used in this study was Simple Random Sampling. The results showed that the average N-Gain Score for the experimental class was 0.76, it was higher than the control class with the score of 0.60. The results of the T-Test indicated that the data resulted in this study met the criteria with the value of tcount = 18,812 ˃ ttable = 1,97897 meaning that Ha is accepted. It can be concluded that the Project Based Learning Model has an influence on the students' problem-solving competence in learning acid-base.
Effects of the Extraction Methods on the Total Phenolic Content, the Total Flavonoid Content, and the Antioxidant Activity of the Mango (Mangifera indica L.) Leaf Extracts Tinasy, Nur Audiyah; Wijayati, Nanik
Indonesian Journal of Chemical Science Vol. 13 No. 3 (2024): Indonesian Journal of Chemical Science
Publisher : Prodi Kimia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v13i3.9557

Abstract

Bad air conditions can be caused by cigarette smoke, industrial fumes, or vehicle exhaust gases. This condition can result in the emergence of free radicals. A free radical can cause a chain reaction that can damage tissue. This reaction can be dampened by compounds that are antioxidants. Mango leaf (Mangifera indica L.) contain flavonoids, alkaloids, saponins, and tannins. Flavonoid compounds are known to have the ability to act as antioxidants. Flavonoid compounds are highly unstable and can be significantly lost during various stages of processing. Therefore, an efficient extraction process is needed to maintain the compound content in natural ingredients. This research aims to analyze the optimal method that can produce total phenolic content, total flavonoids, and high antioxidant activity. The extraction methods used include ultrasonic wave-assisted extraction, reflux, and maceration. Determination of total phenolic content was carried out using the Folin-Ciocalteu reagent, total flavonoid content was carried out using the AlCl3 reagent, and antioxidant activity was carried out using the DPPH method. The results showed that the highest TPC was obtained by maceration extraction which produced a TPC of 218.86 ± 4.95 mgGAE/g, the highest TPC was obtained by reflux extraction which produced a TFC of 301.97 ± 30.07 mgQE/g, and the highest antioxidant activity was obtained by maceration extraction which produced an IC50 value of 5.20 µg/mL.
VILLAGE APPARATUS PERFORMANCE: THE ROLE OF CULTURE, ORGANIZATION SUPPORT AND JOB SATISFACTION? Sabil, Muhammad Asnawi; Yanto, Heri; Pramono, Suwito Eko; Wijayati, Nanik
Jurnal Ilmiah Ilmu Terapan Universitas Jambi Vol. 8 No. 2 (2024): Volume 8, Nomor 2, December 2024
Publisher : LPPM Universitas Jambi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22437/jiituj.v8i2.35927

Abstract

The performance of village officials has always been a focal point for various parties because the foundation of urban and national progress lies in rural development. However, the performance of village officials in Indonesia is still not optimal. This study aims to investigate the roles of job satisfaction, organizational culture, and perceived organizational support as mediators and moderators in the relationship between competence and performance. The research involved 368 village officials across 19 regencies in West Java province, selected using the inverse root square method. Data collection was conducted through questionnaire distribution using area random sampling methods. Data analysis was performed using Warp PLS method. The findings indicate that job satisfaction successfully mediates the relationship between competence and performance. Organizational culture and perceived organizational support significantly moderate the influence of competence on performance. Village government bodies, village community empowerment agencies, and the Ministry of Villages need to formulate policies that support improving job satisfaction, foster a healthy organizational culture, and provide facilitative support, both in infrastructure and in developing hard and soft skills for village officials.
Implementasi Model Pembelajaran Project Based Learning Berdiferensiasi untuk Meningkatkan Kemampuan Kerja Sama Peserta Didik SMP Negeri 32 Surabaya Suryanto, Adi; Harmanto, Harmanto; Wijayati, Nanik
J-CEKI : Jurnal Cendekia Ilmiah Vol. 4 No. 3: April 2025
Publisher : CV. ULIL ALBAB CORP

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.56799/jceki.v4i3.7273

Abstract

The purpose of this research is to improve the cooperation of students in grades VIII-G SMP Negeri 32 Surabaya for the 2022/2023 academic year through the implementation of the Differentiated Project Based Learning model in the subject of Pancasila and Citizenship Education. This type of research is Classroom Action Research with a total of 31 subjects. The design of this study uses a design developed by Kemmis, McTaggart and Nixon in two cycles. The data collection technique uses observation and questionnaires. The data analysis used was a quantitative percentage descriptive technique. The results of this study showed a percentage of 71.89% and cycle II showed a percentage of 87.33% and there was an increase between cycle I and cycle II of 15.44%. Based on the results of the study, it can be concluded that the differentiated project-based learning model is able to improve the cooperative ability of students in class VIII-G SMP Negeri 32 Surabaya.
The Role of Mindfulness in Student Emotional Regulation and Academic Achievement: A Review of the Literature Aluintany, Vitasha Geushiria; Wijayati, Nanik; Sumartiningsih, Sri; Yuwono, Agus
Journal of English Language and Education Vol 10, No 4 (2025)
Publisher : Universitas Pahlawan Tuanku Tambusai

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/jele.v10i4.1018

Abstract

This study is a literature review that aims to examine the role of mindfulness in the regulation of emotions and its relation to students' academic achievement. Studies have shown that mindfulness can improve self-awareness, acceptance without judgment, as well as the ability to be present in the present moment. These abilities contribute significantly to healthier and adaptive emotional management. This study uses a literature review approach with  a systematic review type  to understand the relationship between mindfulness, emotion regulation, and student academic achievement. The study relies on scientific articles published between 2020 and 2025 and obtained from trusted sources such as PubMed, ScienceDirect, SpringerLink, Google Scholar, and DOAJ with relevant keywords. Good emotional regulation allows students to be more focused, calm, and resilient in the face of learning pressure, which ultimately has a positive impact on academic achievement. The review also highlights the importance of implementing mindfulness programs in elementary school settings as part of efforts to improve psychological well-being and learning quality. Based on the results of the study, it is recommended that mindfulness be one of the approaches that can be integrated into learning strategies to support students' emotional and academic development in a balanced manner.
Pengembangan Instrumen Tes Three Tier Multiple Choice Berbasis Socio Scientific Issues Terintegrasi Indikator Keterampilan Berpikir Kritis Iffani, Shinta Zulfa; Wijayati, Nanik; Priatmoko, Sigit
Journal of Innovative and Creativity Vol. 5 No. 2 (2025)
Publisher : Fakultas Ilmu Pendidikan Universitas Pahlawan Tuanku Tambusai

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/joecy.v5i2.2703

Abstract

Penelitian ini bertujuan untuk mengembangkan instrumen tes three tier multiple choice berbasis socio scientific issues terintegrasi indikator berpikir kritis pada materi termokimia dengan kriteria baik ditinjau dari validitas, reliabilitas, tingkat kesukaran dan daya beda. Metode penelitian yang digunakan pada penelitian ini adalah metode Rnd dengan model ADDIE (Analyze, Design, Develop, Implement, and Evaluate). Tahapan penelitian diantaranya dengan 1) analisis kebutuhan terhadap siswa, analisis tugas, dan analisis, 2) tahapan design dengan merancang instrument tes; 3) memvalidasi instrument yang dilakukan oleh dosen ahli, hasil validasi instrument dapat digunakan untuk diujicobakan pada kelas XI MAN Demak sebesar 24 peserta didik, 4) tahapan implement dilakukan dengan menguji cobakan skala besar kepada 107 peserta didik, 5) evaluasi dilakukan pada setiap tahapan. Instrumen dikembangkan sebanyak 33 soal, kemudian divalidasi oleh ahli, dan diujicobakan pada skala kecil (24 siswa) dan besar (107 siswa). Hasil analisis menggunakan Model Rasch menunjukkan bahwa 24 soal memenuhi kriteria validitas isi dan empiris, memiliki reliabilitas tinggi (Alpha Cronbach 0,90 pada skala kecil dan 0,81 pada skala besar), serta tingkat kesukaran dan daya beda yang proporsional. Dengan demikian, instrumen ini layak digunakan untuk mengevaluasi keterampilan berpikir kritis siswa dalam konteks pembelajaran kimia berbasis SSI.
Formulasi Sediaan Serum Antioksidan dari Ekstrak Bunga Mawar Merah (Rosa Damascena Mill.) dan Virgin Coconut Oil (VCO) Wijayati, Nanik
Indonesian Journal of Mathematics and Natural Sciences Vol. 48 No. 1 (2025): Volume 48 Nomor 1 Tahun 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/r4b63s11

Abstract

Free radicals caused by UV rays and pollution can make cell damage that results in aging and skin cancer. This research aims to make a natural antioxidant serum product from rose flower extract (EBM) and virgin coconut oil (VCO) to overcome skin problems caused by free radicals. Antioxidant serum works by stabilizing free radicals. Antioxidant serum from EBM/VCO was tested using DPPH method. The results showed characteristics that EBM has 21.86% yield, contains secondary metabolites of flavonoids, phenols, tannins, saponins, and terpenoids, has a total flavonoid content of 19,994.53 mgQE/g with an IC50 value of 48.63 g/mL. The IC50 value of EBM/VCO antioxidant serum with different ratios are F1 (2:0), F2 (4:0), F3 (6:0), F5 (2:2), F5 (4:2), and F6 (6:2) have IC50 values of 260.12 g/mL, g/mL, 93.21 g/mL, 649.24 g/mL, 587.61g/mL, and 495.67g/mL the highest antioxidant result is F3 with a ratio of 6:0. The results of the physical evaluation of the EBM/VCO antioxidant serum has purple color, distinctive aroma, slightly liquid thick texture, has a spreadability of 5.13 - 9.4 cm, and has a pH of 3.83 -4.31. In this study, the low IC50 value was due to poor VCO quality and low pH due to acidic EBM, it is recommended that further research use VCO with better quality.
Penerapan Model Discovery Learning Berbantuan Aplikasi Edmodo Terhadap Motivasi Dan Hasil Belajar Khofifah, Nur; Prasetya, Agung Tri; Haryani, Sri; Wijayati, Nanik
Chemistry in Education Vol 12 No 2 (2023): Terbit bulan Oktober 2023
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/chemined.v12i2.66162

Abstract

Kimia kurang diminati oleh peserta didik karena materi kimia dianggap sulit dipahami. Kesulitan memahami kimia berdampak pada hasil belajar peserta didik. Model Discovery Learning dapat meningkatkan keaktifan dan kemampuan penemuan peserta didik sehingga mereka dapat memperoleh kesuksesan belajar lebih optimal dan membangunkan motivasi belajar. Penelitian ini bertujuan untuk mengetahui motivasi belajar dan hasil belajar peserta didik dengan model Discovery Learning berbantuan aplikasi Edmodo materi Hidrolisis Garam di SMA Negeri 1 Kedungwuni. Cara yang digunakan dalam teknik penarikan sampel yaitu teknik Cluster Random Sampling. Metode pengumpulan data menggunakan metode tes dan non tes. Metode tes berupa soal Multiple Choice untuk mengetahui hasil belajar kognitif peserta didik berupa soal pretest dan soal posttest sedangkan metode non tes berupa lembar angket motivasi untuk mengetahui motivasi belajar peserta didik. Teknik analisis data yang digunakan untuk menguji hipotesis adalah teknik korelasi biserial. Hasil penelitian menunjukkan bahwa terdapat pengaruh positif yang kuat berdasarkan nilai korelasi biserial terhadap motivasi belajar dan hasil belajar yang diperoleh sebesar 0,82 dan 0,80 dengan koefisien determinasi sebesar 64% dan 67,24%. Hal ini menunjukkan bahwa terdapat pengaruh pembelajaran Discovery Learning berbantuan aplikasi Edmodo terhadap hasil belajar dan motivasi belajar pada peserta didik.
ACTIVITY OF ANTIOXIDANT COMPOUNDS IN DIFFERENT VARIETIES OF MANGO LEAVES Lestari, Hartatik Sri; Wijayati, Nanik
Indonesian Journal of Chemical Science Vol. 14 No. 3 (2025): Indonesian Journal of Chemical Science
Publisher : Prodi Kimia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v14i3.22734

Abstract

Exposure to free radicals in the body in amounts that exceed normal limits can trigger the emergence of various diseases. The formation of free radicals can be inhibited or stopped using antioxidant compounds. Mango leaves are one of the natural materials known to contain secondary metabolite compounds such as flavonoids and phenolics that can be used as natural antioxidants. The writing of this article aims to determine the activity of the chemical compound in various kinds of mango leaves as a natural antioxidant to ward off free radicals based on literature review of the original articles conducted through a search engine with keywords antioxidant, mango leaves. The results of antioxidant activity of mango leaves as to free radical scavengers were obtained from 11 varieties, namely arumanis, bacang, gadung, gedong, kasturi, manalagi, podang, binjai, tandui, irwin, and machang pulasan. Mango leaves contain high secondary metabolite compounds that have potential as antioxidants with highly variable activity. The strongest results were shown in the mango gadung variety with an IC50 value of 3,263 ppm (very strong) using maceration method extraction with DPPH test. Factors that can affect the amount of bioactive compounds and antioxidant activity are the type of mango variety and growing location. Mango leaf as an antioxidant has the potential to be utilized for the food, cosmetic, and pharmaceutical industries.
Co-Authors - Jumaeri -, Solikhah A.A. Ketut Agung Cahyawan W Adi Suryanto Afifaturrochmah, Lutfi Agnes Juniarti Chastelyna, Agnes Juniarti Agung Tri Prasetya Agus Yuwono Ali Djamhuri Aluintany, Vitasha Geushiria Amalina, Nur Dina Anggriani, Frida Anggy Rinela Sulistya Rini, Anggy Rinela Sulistya Anita Harum Sari Antonius Tri Widodo Arief Rohman Arina Marissa, Arina Arofah, Barorotul Ulfah Aryono Adhi, Aryono Asbanu, Yoseanno Widi Anugrah Carnawi, Carnawi Christina Astutiningsih Christina Astutiningsih Didik Prasetyoko Drastisianti, Apriliana Dyah Rini Indriyanti Edy Cahyono Eko Budi Susatyo Ella Kusumastuti, Ella Ellianawati, Ellianawati Endang Susilaningsih Enny Ratnaningsih Enny Ratnaningsih Erika Wijayanti Ersanghono K. Ersanghono K., Ersanghono Ersanghono Kusuma Ersanghono Kusumo, Ersanghono F Widhi Mahatmanti Fanny Firman Syah, Fanny Firman Fathur Rokhman Fera Gustri Ariani, Fera Gustri Firstyarikha Habibah, Firstyarikha G, Agnesya Putri Harjito - Harjito Harjito Harjono Harjono Harmanto Harmanto Harno Dwi Pranowo Harno Dwi Pranowo Heri yanto Hertiana, Dita Setya Hertiana, Dita Setya Husna Amalana, Husna Hutasoit, Parpulungan Hutasoit, Parpulungan Iffani, Shinta Zulfa Ika Kusumawati Jayawarsa, A.A. Ketut Jumina Jumina Jumina Jumina Kasmadi Imam Supardi Kasmui -, Kasmui Kharomah, Kharomah Khofifah, Nur Kristianingsih, Desiagi Dwi Kurniasari, Laviona Tiara Kurniawati, Erlinda Eka Kusoro Siadi Kusoro Siadi Laily Isni Farikhati Langgeng Setyo Wibowo Lestari, Etika Ayu Lestari, Hartatik Sri Lestari, Nanda Ayu Lina Herlina Lina Herlina Lisa Amalia Suryana M. Agus Prayitno, M. Agus Machmudah - Margareta Dian Purnamasari, Margareta Dian Marsudi Marsudi Mar’attus Solihah Masturi Masturi Melykhatun, Rizka Ayu Mohammad Agus Prayitno Mohammad Agus Prayitno Mohammad Agus Prayitno Muhammad Afif Muharom, Sidik Muharom, Sidik Murbangun Nuswowati Nasution, Annio Indah Lestari Nico Aditya Wijaya Nindya Ayu Lestari, Nindya Ayu Ningrum, Puji Nugroho, Imam Husnan Nuni Widiarti Nur Faizah Nur Hidayah Nur Kusuma Dewi Nurul Arifin Oktaviana, Sella Pangestika, Ria Rahayu Pratiwi, Khana Fitri Pratono, Ardiyana Prayitno, Mohammad Agus Purwodiningsih, Ristia Putra, Rizki Suhendar Putri, Syarafina Dirinda Rachmadiyono, Dwi Rahayu, Endah Fitriani Ratna Kumala Dewi Resti, Ade Ria Rahayu Pangestika, Ria Rahayu Ria Wulansarie, Ria Riva Ismawati, Riva Riva lsmawati, Riva Robi’ah Adawiyah, Robi’ah rohayati rohayati Rohmawati, Baiti Romawati, Carolina Romawati, Carolina Rosiyanah, Siti Ruliyanti, Tria S Mursiti Sabil, Muhammad Asnawi Salva Mutiara, Denisa Samuel Budi Wardana Kusuma, Samuel Budi Wardana Samuel Budi Wardhana Samuel Budi Wardhana Kusuma Saptorini - Saptorini Saptorini, Saptorini Septiyaningsih, Tri Shakin Ervita Oktaviyani Sigit Priatmoko Siti Anisa Rohmah Siti Handayani Siti Sundari Miswadi Solikhah Solikhah Sri Haryani Sri Haryani Sri Ngabekti Sri Sumartiningsih Sri Supanti Sri Susilogati Sri Susilogati Sumarti SRI WARDANI Suci Mulyati Sudarmin Sudarmin Sudarmin Sudarmin Supartono - Suprapto Suprapto Suprapto, Suprapto Surmatiningsih, Sri Susan Primadevi Susanto, Aris Tri Susanto, Aris Tri Sutikno Madnasri Suwito Eko Pramono Sya'idah, Fatin Atikah Nata Talitha Widiatningrum Tinasy, Nur Audiyah Titik Kushandayani Tri Handayani Triawan, Singgih Ade Triawan, Singgih Ade Triyono Triyono Triyono Triyono Tunggul Pawenang, Eram Ulya, Isnaeni Nurul Veronita, Fanna Veronita, Fanna Wahyuningtyas, Wulan Wara Dyah Pita Rengga Watoni, Edi Satria Wawan Wawan Widarti, Nuni Widya Hary Cahyati Wijianto, Wijianto Woro Sumarni Yayuk Tutiek Supriyanti Yeni Anita Sari yoga agung prabowo Yosepphiene Debbie Damayani Yuliyati, Tri Budi Yunita, Wulansari Zaenuri Zaenuri