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All Journal Jurnal Teknologi Dan Industri Pangan VALENSI Jurnal Ilmu Lingkungan AL KAUNIYAH Alchemy : Journal of Chemistry Bulletin of Chemical Reaction Engineering & Catalysis Proceeding International Conference on Global Resource Conservation JITRO (Jurnal Ilmiah dan Teknologi Peternakan Tropis) Elkawnie EduChemia: Jurnal Kimia dan Pendidikan ALCHEMY Jurnal Penelitian Kimia Jurnal Kimia Terapan Indonesia Jurnal Riset Sains dan Kimia Terapan Journal of Social Research Bulletin of Chemical Reaction Engineering & Catalysis al Kimiya : Jurnal Ilmu Kimia dan Terapan
Dede Sukandar
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Agriculture, Biological Sciences & Forestry Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Economics, Econometrics & Finance Education Energy Engineering Environmental Science Health Professions Industrial & Manufacturing Engineering Materials Science & Nanotechnology Social Sciences Veterinary Other

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Effect of Additional Polyethylene Glycol and Citric Acid on Characteristics of NiMo/g-Al2O3 Catalyst in Light Cycle Gas Oil Hydrodesulfurisation Dede Sukandar; Lailatul Badriyah; Wawan Rustyawan; Adawiah Adawiah
Bulletin of Chemical Reaction Engineering & Catalysis 2023: BCREC Volume 18 Issue 1 Year 2023 (April 2023)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.17036

Abstract

Sulfur is an impurity in diesel that causes low product quality and environmental pollution. Therefore, a catalyst is needed in the profound hydrodesulfurization (HDS) reaction to produce diesel fuel with low sulfur content. The catalyst synthesized in this work was NiMo/g-Al2O3 with the addition of PEG (2%, 4%, 6%) (w/w) and CA (1%, 2%, and 4%) (w/w). The catalyst was synthesized using the dry impregnation method with a metal concentration of 3% NiO and 15% MoO3. The obtained catalysts were characterized using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Surface Area Analyzer (SAA). This work acquired the best catalyst characteristics for the HDS process by adding 2% PEG and 1% CA with a concentration of 3.19% NiO and 13.98% MoO3. The surface area, pore volume, and diameter are 181.655 m2/g, 0.50 cm3/g, and 110.51 Å, respectively. The catalyst activity satisfies Euro V standards at 345 ℃ with a sulfur content of 9.55 ppm, and the sulfur conversion (HDS) is 98.75%. The density and cetane index of the obtained diesel fuel was 0.798 g/mL and 53.6, respectively. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Effect of Additional Polyethylene Glycol and Citric Acid on Characteristics of NiMo/g-Al2O3 Catalyst in Light Cycle Gas Oil Hydrodesulfurisation Dede Sukandar; Lailatul Badriyah; Wawan Rustyawan; Adawiah Adawiah
Bulletin of Chemical Reaction Engineering & Catalysis 2023: BCREC Volume 18 Issue 1 Year 2023 (April 2023)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.17036

Abstract

Sulfur is an impurity in diesel that causes low product quality and environmental pollution. Therefore, a catalyst is needed in the profound hydrodesulfurization (HDS) reaction to produce diesel fuel with low sulfur content. The catalyst synthesized in this work was NiMo/g-Al2O3 with the addition of PEG (2%, 4%, 6%) (w/w) and CA (1%, 2%, and 4%) (w/w). The catalyst was synthesized using the dry impregnation method with a metal concentration of 3% NiO and 15% MoO3. The obtained catalysts were characterized using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Surface Area Analyzer (SAA). This work acquired the best catalyst characteristics for the HDS process by adding 2% PEG and 1% CA with a concentration of 3.19% NiO and 13.98% MoO3. The surface area, pore volume, and diameter are 181.655 m2/g, 0.50 cm3/g, and 110.51 Å, respectively. The catalyst activity satisfies Euro V standards at 345 ℃ with a sulfur content of 9.55 ppm, and the sulfur conversion (HDS) is 98.75%. The density and cetane index of the obtained diesel fuel was 0.798 g/mL and 53.6, respectively. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Aktivitas Penghambatan α-Glukosidase Campuran Ekstrak Daun Namnam (Cynometra cauliflora L.) dan Madu Kaliandra La Ode Sumarlin; Dede Sukandar; Lia Pratiwi
al Kimiya: Jurnal Ilmu Kimia dan Terapan Vol 6, No 2 (2019): al Kimiya: Jurnal Ilmu Kimia dan Terapan
Publisher : Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/ak.v6i2.6577

Abstract

Penyakit diabetes melitus adalah disfungsi metabolisme karbohidrat. Terapi antidiabetes oral yaitu menggunakan agen penghambat α-glukosidase. Oleh karena itu perlu dilakukan kajian agen penghambat α-glukosidase yang potensial diantaranya madu kaliandra dan ekstrak daun namnam.  Kajian ini akan difokuskan pada kemampuan sampel tersebut sebagai agen penghambat α-glukosidase baik dengan perlakuan bentuk tunggal maupun campuran, sebelum dan setelah fraksinasi. Selain itu digunakan FTIR (Fourier Transform Infrared) untuk mengetahui golongan senyawa pada setiap perlakuan sampel tersebut. Uji aktivitas penghambatan α-glukosidase secara in vitro pada ekstrak daun namnam menunjukkan nilai IC50 sebesar 34,47 ppm, sedangkan madu kaliandra tidak menunjukkan aktivitas penghambatan α-glukosidase. Hasil fraksinasi cair-cair menunjukkan bahwa ekstrak n-heksana mampu menghambat α-glukosidase tertinggi berdasarkan nilai IC50 sebesar 8,46 ppm. Hasil karakterisasi menggunakan spektrofotometer FTIR pada ekstrak n-heksana mengandung gugus fungsi yang memiliki kemiripan dengan golongan senyawa steroid. Senyawa aktif pada ekstrak etil asetat dan ekstrak n-butanol mengandung gugus fungsi yang memiliki kemiripan dengan gugus fungsi standar senyawa kuersetin.
Sonochemical Assisted Synthesis of Cr-PTC Metal Organic Framework, ZnO, and Fe3O4 Composite and Their Photocatalytic Activity in Methylene Blue Degradation Nurbayti, Siti; Adawiah, Adawiah; Bale, Uly Fitria; Fadhilla, Rizka; Ramadhan, Fitri Nur; Zulys, Agustino; Sukandar, Dede; Saridewi, Nanda; Tulhusna, Latifah
Bulletin of Chemical Reaction Engineering & Catalysis 2024: BCREC Volume 19 Issue 2 Year 2024 (August 2024)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20156

Abstract

Methylene blue pollutants can be treated by photocatalytic methods using metal oxide-based semiconductor materials and metal organic framework (MOF). These two materials are often coupled into a composite to improve their physicochemical properties and catalytic activity. This research focuses on the synthesis of composites based on Cr-PTC MOF, ZnO, and Fe3O4 by the sonochemical method. The obtained composites were characterized and tested for catalytic activity in methylene blue pollutant degradation in an aqueous system under acidic conditions (pH = 5). Our investigation shows that the Cr-PTC@Fe3O4 composite possesses the lowest band gap energy of 1.86 eV and achieves the highest photocatalytic activity in methylene blue degradation at solution pH = 5, with a percent degradation of 84.36%. The sonochemical incorporation of Fe3O4 and Cr-PTC MOF is able to fabricate materials in a short time with better photocatalytic activity in degrading methylene blue than the single materials. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Synthesis of Metal-Organic Framework (MOF) Cr-PTC-HIna for Heavy Metal Ion Adsorption Nurhasni, Nurhasni; Adawiah, Adawiah; Wahyudin, Wahyudin; Hadriyani, Rizka; Andriyani, Leni; Fadhilla, Rizkha; Zulys, Agustino; Sukandar, Dede
Bulletin of Chemical Reaction Engineering & Catalysis 2024: BCREC Volume 19 Issue 1 Year 2024 (April 2024)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20069

Abstract

As an adsorbent material, Metal-Organic Framework (MOF) provides several advantages, such as large surface area and pore volume, as well as stability in aqueous systems both in acidic, basic, and neutral conditions. The research successfully made a metal organic framework (MOF) from chromium and perylene that was modulated by isonicotinic acid. This was done using three different methods: hydrothermal (Cr-PTC-HIna-HT), solvothermal (Cr-PTC-HIna-ST), and sonochemical (Cr-PTC-HIna-SC). The Cr-PTC-HIna-SC showed the greatest Pb2+ ion adsorption capacity. The optimum adsorption of Pb2+ ions occurred at 150 ppm Pb2+ ion concentration, pH 5, 90 minutes of contact time, and an adsorption capacity of 149.95 mg/g at 35 °C. The dominant adsorption isotherm model is the Langmuir isotherm model with R2 = 0.9867 and follows the pseudo-second-order. The selectivity test showed that Cr-PTC-HIna-SC MOF could adsorb more Cd2+ ions than Pb2+ ions, with 250 mg/g being the best amount.
Isolasi dan Identifikasi Metabolit Sekunder dari Kulit BatangBintangur (CALOPHYLLUM BICOLOR) Sukandar, Dede -; Abbas, Jamillah; Habibah, Nurfitriany; Rudiana, Tarso; Rohman, Saeful
ALCHEMY:Journal of Chemistry Vol 12, No 2 (2024): ALCHEMY: JOURNAL OF CHEMISTRY
Publisher : Department of Chemistry, Faculty of Science and Technology UIN Maulana Malik Ibrahim Malan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/al.v12i2.26634

Abstract

Isolation and identification of secondary metabolite compounds from stem bark of Bintangur (Calophyllum bicolor) have been reported. Isolation was carried out using the maceration method with 70% ethanol solvent and fractionation of the ethanol extract by column chromatography using n-hexane solvent. The n-hexane fraction resulting from column chromatography was subjected to gravity chromatography with the mobile phase n-hexane: ethyl acetate (8:2) producing isolate 1. The results of purification of isolate 1 using fast column chromatography with the mobile phase dichloromethane: methanol (1:1) and a UV light detector at ƛ 254 nm, compound 1 was obtained. Meanwhile, identification of compound 1 was carried out through UV-Vis spectroscopy, FTIR and LCMS analysis. The identification results of compound 1 using UV-Vis spectroscopy showed the presence of an aliphatic ring double bond chromophore (λmax 233.5; 295 nm). FTIR results indicated the presence of vibrations of the OH group (3417 cm-1), CH alkanes (2933; 2864; 1456; 545 cm-1), and C=C alkenes (1618 cm-1). Analysis results using LCMS showed a molecular ion peak at [M]+ m/z = 386.96 at a retention time of 11.6 minutes, indicating a molecular weight of 386 and a molecular formula (C27H46O) that corresponds to a terpenoid compound. Keywords: isolation, identification, terpenoid, bintangur (Calophyllum bicolor) AbstrakIsolasi dan identifikasi senyawa metabolit sekunder dari kulit batang bintangur   (Calophyllum   bicolor)   telah   dilaporkan.  Isolasi dilakukan dengan metode maserasi dengan pelarut etanol 70% dan fraksinasi ekstrak etanol dengan kromatografi kolom menggunakan pelarut n-heksana. Fraksi n-heksana hasil kromatografi kolom dikromatografi grafitasi dengan fase gerak n- heksana : etil asetat (8:2) menghasilkan isolat 1. Hasil pemurnian isolat 1 menggunakan kromatografi kolom cepat dengan fase gerak diklorometana : metanol (1:1) dan  detektor sinar UV pada ƛ 254 nm diperoleh senyawa    1. Sedangkan identifikasi  senyawa 1 dilakukan melalui analisis spektroskopi UV-Vis, FTIR, dan LCMS. Hasil identifikasi senyawa 1 menggunakan spektroskopi UV-Vis  menunjukkan adanya kromofor ikatan rangkap cincin alifatik (λmaks 233,5 nm; 295 nm). Hasil FTIR mengindikasikan adanya vibrasi gugus OH (3417     cm-1), CH alkana (2933; 2864; 1456; 545 cm-1), dan C=C alkena (1618 cm-1). Hasil Analisa menggunskan LCMS menujukkan puncak ion molekul pada [M]+ m/z = 386,96 pada waktu retensi 11,6 menit, menunjukkan berat molekul 386 dan rumus molekul (C27H46O) yang sesuai dengan senyawa terpenoid. Kata kunci: isolasi, elusidasi, terpenoid, bintangur (Calophyllum bicolor)
ISOLASI DAN IDENTIFIKASI SENYAWA METABOLIT SEKUNDER DARI KULIT BATANG BINTANGUR (CALOPHYLLUM BICOLOR) Sukandar, Dede
ALCHEMY:Journal of Chemistry Vol 11, No 2 (2023): ALCHEMY: JOURNAL OF CHEMISTRY
Publisher : Department of Chemistry, Faculty of Science and Technology UIN Maulana Malik Ibrahim Malan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/al.v11i2.26633

Abstract

 AbstractIsolation and identification of secondary metabolite compounds from stem bark of Bintangur (Calophyllum bicolor) have been reported. Isolation was carried out using the maceration method with 70% ethanol solvent and fractionation of the ethanol extract by column chromatography using n-hexane solvent. The n-hexane fraction resulting from column chromatography was subjected to gravity chromatography with the mobile phase n-hexane: ethyl acetate (8:2) producing isolate 1. The results of purification of isolate 1 using fast column chromatography with the mobile phase dichloromethane: methanol (1:1) and a UV light detector at ƛ 254 nm, compound 1 was obtained. Meanwhile, identification of compound 1 was carried out through UV-Vis spectroscopy, FTIR and LCMS analysis. The identification results of compound 1 using UV-Vis spectroscopy showed the presence of an aliphatic ring double bond chromophore (λmax 233.5; 295 nm). FTIR results indicated the presence of vibrations of the OH group (3417 cm-1), CH alkanes (2933; 2864; 1456; 545 cm-1), and C=C alkenes (1618 cm-1). Analysis results using LCMS showed a molecular ion peak at [M]+ m/z = 386.96 at a retention time of 11.6 minutes, indicating a molecular weight of 386 and a molecular formula (C27H46O) that corresponds to a terpenoid compound. Keywords: isolation, identification, terpenoid, bintangur (Calophyllum bicolor) AbstrakIsolasi dan identifikasi senyawa metabolit sekunder dari kulit batang bintangur   (Calophyllum   bicolor)   telah   dilaporkan.  Isolasi dilakukan dengan metode maserasi dengan pelarut etanol 70% dan fraksinasi ekstrak etanol dengan kromatografi kolom menggunakan pelarut n-heksana. Fraksi n-heksana hasil kromatografi kolom dikromatografi grafitasi dengan fase gerak n- heksana : etil asetat (8:2) menghasilkan isolat 1. Hasil pemurnian isolat 1 menggunakan kromatografi kolom cepat dengan fase gerak diklorometana : metanol (1:1) dan  detektor sinar UV pada ƛ 254 nm diperoleh senyawa    1. Sedangkan identifikasi  senyawa 1 dilakukan melalui analisis spektroskopi UV-Vis, FTIR, dan LCMS. Hasil identifikasi Asiahoki77 juga memberikan berbagai bonus dan promosi menarik untuk para anggotanya. Bonus selamat datang, bonus deposit, dan promosi mingguan adalah beberapa di antaranya. Ini tidak hanya menambah keseruan bermain tetapi juga memberikan nilai tambah bagi para pemain senyawa 1 menggunakan spektroskopi UV-Vis  menunjukkan adanya kromofor ikatan rangkap cincin alifatik (λmaks 233,5 nm; 295 nm). Hasil FTIR mengindikasikan adanya vibrasi gugus OH (3417     cm-1), CH alkana (2933; 2864; 1456; 545 cm-1), dan C=C alkena (1618 cm-1). Hasil Analisa menggunskan LCMS menujukkan puncak ion molekul pada [M]+ m/z = 386,96 pada waktu retensi 11,6 menit, menunjukkan berat molekul 386 dan rumus molekul (C27H46O) yang sesuai dengan senyawa terpenoid. Kata kunci: isolasi, elusidasi, terpenoid, bintangur (Calophyllum bicolor) 
Synthesis of MgFe2O4 Nanoparticles and its Application for Photodegradation of Methylene Blue Sukandar, Dede; Adawiah, Adawiah; Rohman, Saeful; Fitria, Shella; Saridewi, Nanda; Farishi, Salman; Nurhasni, Nurhasni; Aziz, Isalmi; Azizah, Yulyani Nur
Bulletin of Chemical Reaction Engineering & Catalysis 2024: BCREC Volume 19 Issue 4 Year 2024 (December 2024)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.20222

Abstract

Methylene blue wastewater from the paper, clothing, and textile industries can adversely affect aquatic ecosystems if improperly treated. One method to treat methylene blue pollutants in sewage is through photocatalysis techniques using magnesium ferrite (MgFe2O4) nanoparticle-based semiconductors. The MgFe2O4 is effective for methylene blue degradation because it is stable in aqueous systems, inexpensive, and has good photocatalytic activity. This study aims to synthesize MgFe2O4 nanoparticles with pumpkin seed extract (Cucurbita moschata) as a capping agent through a hydrothermal method. Characterization results show that MgFe2O4 nanoparticles synthesized with the addition of 3 mL pumpkin seed extract have a crystal size of 3.87 nm, cubic spinel structure, average particle size of 29 nm, and band gap energy value of 1.94 eV. The MgFe2O4 nanoparticles produced optimum degradation efficiency under mercury lamp irradiation with a degradation capacity of 391.98 mg/g at pH 12. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Pemantauan Konsentrasi Radionuklida Cs-137, Co-60, I-131 Serta Kualitas Air Daerah Aliran Sungai Bekasi Sukandar, Dede; Amri, Ghulam Fathul; Dasumiati, Dasumiati; Fauzih, Dewi
Jurnal Ilmu Lingkungan Vol 23, No 1 (2025): January 2025
Publisher : School of Postgraduate Studies, Diponegoro Univer

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jil.23.1.23-34

Abstract

Radionuklida menjadi sesuatu yang krusial untuk diketahui penyebaran, intensitas radiasi, sumber dan proses yang mempengaruhinya di dalam air. Diantara radionuklida yang menarik perhatian adalah Cs-137, Co-60, I-131. Radionuklida Cs-137 adalah unsur radioaktif yang memiliki sifat mudah terdispersi dalam badan air, sedangkan Co-60 dan I-131 banyak digunakan untuk keperluan rumah sakit khususnya radioterapi. Penelitian ini bertujuan untuk mengetahui konsentrasi radionuklida Cs-137, Co-60, I-131 serta kualitas air di Sungai Bekasi. Analisis karakteristik sifat air dari Sungai Bekasi adalah suhu, pH, dan Total Dissolved Solids (TDS), dan pemekatan. Pengukuran konsentrasi radionuklida Cs-137, Co-60, dan I-131 menggunakan instrumen spektrometer gamma. Hasil penelitian diperoleh konsentrasi radionuklida Cs-137, Co-60, dan I-131 adalah masing-masing berturut-turut: 0,00642 - 0,00428 Bq/L, 0,00713 - 0,01272 Bq/L dan 0,00077 - 0,00584 Bq/L.  Konsentrasi radionuklida Cs-137, Co-60, I-131 masih berada di bawah batas aman (Cs-137 1,2 x 102 Bq/L ,  Co-60 1,4 x 103 Bq/L, I-131 3,0 x 105 Bq/L) yang ditetapkan oleh Peraturan Kepala BAPETEN Nomor 7 Tahun 2013. Pada penentuan kualitas air berdasarkan parameter suhu, TDS, dan pH hasil yang didapatkan masih dibawah batas aman (suhu 25-310C, TDS 1000 mg/L , pH 6-9) dalam kategori kelas II yang ditetapkan oleh Peraturan Pemerintah No 22 Tahun 2021.
Co-Authors A Sa’duddin A.S. Satyaningtijas Abbas, Jamillah Achmad Tjahja Adawiah Adawiah Adawiah Adawiah adawiah adawiah, adawiah Adeng Hudaya Adeng Hudaya Adid Adep Dwiatmoko Agik Suprayogi Agustino Zulys Ahmad Fathoni Ahmad Tjahja Nugraha, Ahmad Tjahja Ai Faziah Hayati Alfindah Rusanti Amri, Ghulam Fathul Andriyani, Leni Anna Muawanah Anny Sulaswatty Bale, Uly Fitria Chitta Putri Novianti Dasumiati Dasumiati Eka Rizki Amelia Eka Rizki Amelia Eka Rizki Amelia Eka Rizki Amelia Eka Rizki Amelia Eka Rizki Amelia Elda Suci Yala Merru Emi Lestari Emi Lestari Eva Silvia Fadhilla, Rizka Fadhilla, Rizkha Farishi, Salman Fauzan Aulia Fauzih, Dewi Fitria, Shella Fitriyanti Fitriyanti Fuady Hanief Habibah, Nurfitriany Hadriyani, Rizka Hendrawati Hendrawati Hilyatuz Zahroh Hilyatuz Zahroh Ibnu Umarudin Umedi Idzni Qistina Ika Amalia, Ika Ika Restu Purwanti Imam Hamidi Imamah Al Mabrur Imamah Al Mabrur Ira Djajanegara Ira Djajanegara Ira Jayanegara Ira Jayanegara Isalmi Aziz Khilda Fithri Aryani Khoeriyah Khoeriyah La Ode Sumarlin Lailatul Badriyah Lia Pratiwi Melina Hadera Muhamad Zaenudin Nanda Saridewi, Nanda Nani Radiastuti Nani Radiastuti Nani Radiastutu Nina Artanti Nino Rinaldi Nurhasni Nurhasni Nurlaela Nurlaela Rahminiwati, Min Ramadhan, Fitri Nur Rina Ningtiyas Rista Kurnia Dewi Rizky Achmad Fauzi Saeful Rohman Sandra Hermanto Septyani Nurichawati Sihono Sihono Silvester Tursiloadi Siti Nurbayti Siti Nurbayti Siti Nurbayti Sofnie M Chairul Sri Yadial Chalid Sudiyarmanto Sudiyarmanto Syarifah Utami Tarso Rudiana, Tarso Teguh Wahyono Tiah Maharani Tri Heru Prihadi Trilaksono Trilaksono Tsalats Wahyul Husna Tulhusna, Latifah Wahyudin Wahyudin Wawan Rustyawan Widad Basalamah Widhi Kurniawan Yulyani Nur Azizah