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CHEMICAL DEGRADATION OF NAFION MEMBRANES UNDER PEMFC AS INVESTIGATED BY DFT METHOD Sanjaya, Rochmad K; Juliandri, Juliandri; Rahayu, Iman; Ismillayli, Nurul; hermanto, dhony
Jurnal Sains Materi Indonesia Vol 21, No 2: JANUARY 2020
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (916.989 KB) | DOI: 10.17146/jsmi.2020.21.2.5582

Abstract

CHEMICAL DEGRADATION OF NAFION MEMBRANES UNDER PEMFC AS INVESTIGATED BY DFT METHOD. An exsitu method has been developed to performance of Nafion's membrane in PEMFC (Proton Electrolyt Membrane Fuel Cells), caused by the chemical degradation of ·OH and ∙H radicals. The change of the chemical structure occurring during the degradation were primarily calculated of the relative energy of reactions by DFT (Density Functional Theory) method approach in the Gaussian software. This study aims to determine whether DFT method with functional B3LYP, PBEPBE, and B3PW91 and base sets 6-311++G can be used in determining the relative energy of a reaction and knowing the difference in role between ·OH and ∙H in the degradation process of the main chain Nafion with the final group are -CF2H, -CF=CF2 and -COOH. The three functionalities applied showed that the ·OH radical has more role than the ∙H radical in the degradation process of the Nafion main chain. In the -CF2H group was shown the relative energy value of reaction 2 is lower than reaction 5, in the -CF=CF2 group was shown the relative energy value of reaction 8* is lower than reaction 11 and in the -COOH group the relative energ value of reaction 14 is lower than reaction 16. By knowing the relative energy of the Nafion main chain degradation reaction with a certain final group and the role of certain radical compounds in the degradation process, the DFT method with functional B3LYP, PBEPBE and B3PW91 and base sets 6-311++G can recommend various modifications of the Nafion as a fuel cell membrane, particularly in increasing of membrane performance.
Pemanfaatan Kompleks Polielektrolit sebagai Matriks untuk Immobilisasi Urease dan Aplikasinya sebagai Membran Biosensor Pemonitoran Hg(II) Dhony Hermanto; Mudasir Mudasir; Dwi Siswanta; Bambang Kuswandi
Al-Kimia Vol 7 No 1 (2019): JUNE
Publisher : Study Program of Chemistry - Alauddin State Islamic University of Makassar

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24252/al-kimia.v7i1.6247

Abstract

The preparation of polyelectrolyte complex (PEC) as supporting material of urease immobilisation for  Hg(II) biosensor has done. PEC membrane can be prepared by mixing hydrosol alginate and chitosan hydrosol with 1: 1 ratio at pH of 5.28 approximately. The optimum conditions and characteristics of biosensor was determined. The formed alginate–chitosan PEC membrane was confirmed by using FTIR spectroscopy and SEM analysis. The results shoed that PEC of alginate-chitosan was formed and the proposed biosensor is an excellent platform for sensitive detection of Hg (II).
Isolasi dan Karakterisasi Asam Humat dari Tanah Dasar Bendungan Batujai Lombok Tengah NTB Nurul Ismillayli; Dhony Hermanto
Al-Kimia Vol 7 No 1 (2019): JUNE
Publisher : Study Program of Chemistry - Alauddin State Islamic University of Makassar

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24252/al-kimia.v7i1.6274

Abstract

This study deals with the isolation and characterization of humic acids from Batujai Dam subgrade, Central Lombok. Humic acid isolated by using recommended method of the International Humic Substances Society and purified by 0.1M HCl/0.3 M HF solution. Humic acid isolated then were determined ash content, total acidity, carboxilic and phenolic group content and characterized using FTIR spectroscopy.  FTIR analyses of isolated humic acid samples have shown the presence of carboxylic, phenols, alcoholic, amines functional groups, aliphatic hydrocarbon and aromatic ring. The result of ash content determination showed that purification decreased ash content from 5.60% to 1.13%. Total acidity of humic acid was 630 cmol/kg, acidity of –COOH was 226 cmol/kg, and –OH fenolic acidity was 404  cmol/kg.
Determination of Ascorbic Acid Content using the Reverse Phase–High Performance Liquid Chromatography (RP-HPLC) Method Nurul Ismillayli; Dhony Hermanto; I. G. A. Sri Andayani; Ruru Honiar; Ulul Khairi Zuryati; Baiq Mariana; Linda Marta Shofiyana
Al-Kimia Vol 8 No 2 (2020): DECEMBER
Publisher : Study Program of Chemistry - Alauddin State Islamic University of Makassar

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24252/al-kimia.v8i2.15097

Abstract

A method of reverse phase-high performance liquid chromatography (RP-HPLC) was evaluated in ascorbic acid determination. The determination was conducted at optimum conditions for RP-HPLC method, including ethanol as mobile phase, flow velocity of 0.8 mL/min, running time of 5 minutes, injection volume of 10 µL, UV detector, wavelength of 245 nm with internal standard of ascorbic acid in metaphosphate-acetic acid. Result of measurement was validated by AOAC Official Method 967.21. It was obtained that RP-HPLC method was high sensitive and precision method due to its limit of detection was 0,5 µg/mL and  RSD  was ≤ 2%. The results of the determination of vitamin C content in fresh ceruring fruit using RP-HPLC method and the titrimetry method namely, 52.9057 ± 0.17 and 54.2066 ± 0.87 mg in 100 g sample, respectively. Based on statistical analysis (t-test), there were no significant differences for the two methods used. The percentage of recovery obtained is excellent in the range of 97.9-104.3%. Therefore, the RP-HPLC method is expected to be an accurate method for routine analysis of vitamin C. Key word: ascorbic acid, reverse phase, HPLC, titrimetric. 
CHEMICAL DEGRADATION OF NAFION MEMBRANES UNDER PEMFC AS INVESTIGATED BY DFT METHOD Rochmad K Sanjaya; Juliandri Juliandri; Iman Rahayu; Nurul Ismillayli; dhony hermanto
Jurnal Sains Materi Indonesia Vol 21, No 2: JANUARY 2020
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (916.989 KB) | DOI: 10.17146/jsmi.2020.21.2.5582

Abstract

CHEMICAL DEGRADATION OF NAFION MEMBRANES UNDER PEMFC AS INVESTIGATED BY DFT METHOD. An exsitu method has been developed to performance of Nafion's membrane in PEMFC (Proton Electrolyt Membrane Fuel Cells), caused by the chemical degradation of ·OH and ∙H radicals. The change of the chemical structure occurring during the degradation were primarily calculated of the relative energy of reactions by DFT (Density Functional Theory) method approach in the Gaussian software. This study aims to determine whether DFT method with functional B3LYP, PBEPBE, and B3PW91 and base sets 6-311++G can be used in determining the relative energy of a reaction and knowing the difference in role between ·OH and ∙H in the degradation process of the main chain Nafion with the final group are -CF2H, -CF=CF2 and -COOH. The three functionalities applied showed that the ·OH radical has more role than the ∙H radical in the degradation process of the Nafion main chain. In the -CF2H group was shown the relative energy value of reaction 2 is lower than reaction 5, in the -CF=CF2 group was shown the relative energy value of reaction 8* is lower than reaction 11 and in the -COOH group the relative energ value of reaction 14 is lower than reaction 16. By knowing the relative energy of the Nafion main chain degradation reaction with a certain final group and the role of certain radical compounds in the degradation process, the DFT method with functional B3LYP, PBEPBE and B3PW91 and base sets 6-311++G can recommend various modifications of the Nafion as a fuel cell membrane, particularly in increasing of membrane performance.
OPTIMALISASI INTEGRASI SAPI, JAGUNG, DAN RUMPUT LAUT (PIJAR) PADA TEKNOLOGI PENGOLAHAN PAKAN TERNAK BERBASIS LIMBAH PERTANIAN JAGUNG – RUMPUT LAUT GUNA MENDUKUNG PROGRAM BUMI SEJUTA SAPI (BSS) DI NUSA TENGGARA BARAT Erin Ryantin Gunawan; Dedi Suhendra; Dhony Hermanto
Buletin Peternakan Vol 37, No 3 (2013): BULETIN PETERNAKAN VOL. 37 (3) OKTOBER 2013
Publisher : Faculty of Animal Science, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21059/buletinpeternak.v37i3.3086

Abstract

Penelitian ini bertujuan untuk mengetahui optimalisasi integrasi sapi, jagung, dan rumput laut (pijar) dengan pengolahan teknologi pakan ternak berbasis limbah pertanian jagung–rumput laut yang telah dilakukan guna mendukung Program Bumi Sejuta Sapi (BSS) di Nusa Tenggara Barat. Penelitian dilaksanakan di Kecamatan Bayan Kabupaten Lombok Utara – NTB pada bulan Juli hingga Desember 2012. Peningkatan kualitas pakan meliputi nilai nutrisi dan daya simpannya diperoleh melalui fermentasi jerami jagung yang diikuti dengan suplementasi pakan menggunakan bahan tambahan pakan rumput laut. Perubahan kualitas pakan diketahui dengan membandingkan kadar karbohidrat (gula pereduksi), protein kasar, lemak, serat kasar, mineral (Ca, Fe, dan P), lignin, selulosa, dan hemiselulosa antara pakan ternak komplit, jerami jagung terfermentasi-rumput laut, dan jerami jagung non fermentasi. Fermentasi jerami jagung dilakukan dengan melakukan variasi perbandingan kadar jerami jagung, probiotik (starbio dan EM4), urea dan molases, meliputi PG1, PG2, PG3, PG4, dan PG5. Data masing-masing parameter diuji dengan uji ANOVA satu jalur untuk mengetahui signifikansi efek dari beberapa perlakuan pakan. Uji organoleptik yang dilakukan meliputi warna dan bau. Suhu dan keasaman pakan pada masing masing perlakuan juga diukur. Variabel pada ternak sapi yang diukur adalah perubahan lingkar dada serta panjang badan sapi akibat pemberian pakan dengan jumlah yang ditentukan dalam kurun waktu 5 minggu. Sapi yang digunakan adalah 5 ekor sapi Bali jantan umur 18-24 bulan. Hasil penelitian menunjukkan bahwa jerami jagung fermentasi berkualitas baik memiliki bentuk seperti dalam keadaan segar yaitu memiliki warna coklat kekuning-kuningan, aroma bau yang khas, dan berdaya simpan lama (hingga bulan ke-2 penyimpanan). Hasil uji ANOVA satu jalur pada masing-masing parameter gizi menunjukkan bahwa perbedaan perlakuan fermentasi menghasilkan kadar gizi yang signifikan berbeda. Proses fermentasi jerami jagung meningkatkan protein kasar, gula pereduksi, dan menurunkan serat kasar, lemak, mineral (Ca, Fe dan P), lignin, selulosa, dan hemiselulosa. Peningkatan kadar karbohidrat tertinggi diperoleh pada perlakuan PG5 yaitu 15,50%, sedangkan peningkatan kadar protein tertinggi diperoleh pada PG3, yaitu 11,60%. Pemberian jerami jagung yang disuplementasi rumput laut 10% selama 5 minggu dapat menghasilkan perubahan lingkar dada dan panjang badan sapi tertinggi pada perlakuan PG5+R.(Kata kunci: Limbah pertanian, Jerami jagung, Rumput laut, Pakan)
Penentuan Kandungan Etanol dalam Makanan dan Minuman Fermentasi Tradisional Menggunakan Metode Kromatografi Gas dhony hermanto
CHEMPUBLISH JOURNAL Vol. 5 No. 2 (2020): Chempublish Journal
Publisher : Universitas Jambi, Fakultas Sains dan Teknologi, Program Studi Kimia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22437/chp.v5i2.8979

Abstract

Determination of alcohol content in food and beverage is needed for halal verification. Ethanol content in various food and beverage traditional products from fermentation was determined using the gas chromatography method with ethanol as standart and n-buthanol as internal standart. As comparison, measurement using alcohol meter were conducted. The GC measurement result were also compared with alcohol content printed on the packaging (value declared by the producer). The result showed that linear range in ethanol concentration was 1-10% with correlation coefficient (r) of 0.9984, indicated that GC has excellent linearity. Limit of detection was 0,5 ng, coefficient variance (CV) was ≤ 2%, accuracy (K) was ≤ 5% and recovery was > 2%, indicated that GC method has high sensitivity, accuracy, validity and recovery. Alcohol content in beer samples listed in the packaging was confirmed with GC measurement results. Anova test results showed that the GC methods with alcohol meter methods did not differ significantly so that the GC and alcohol meter methods can be used as a good alternative in determining the ethanol content in fermented foods and beverages as a support in halal verification.
Polyelectrolyte Complex (PEC) of the Alginate-Chitosan Membrane for Immobilizing Urease Dhony Hermanto; Mudasir Mudasir; Dwi Siswanta; Bambang Kuswandi; Nurul Ismillayli
Journal of Mathematical and Fundamental Sciences Vol. 51 No. 3 (2019)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2019.51.3.8

Abstract

PEC of the alginate-chitosan membrane as supporting material for immobilizing urease was produced. This study aimed to develop a supporting material for enzyme immobilization that has high stability, a fast response time and an easy and relatively inexpensive preparation procedure. An alginate-chitosan PEC membrane was produced by reacting alginate hydrosol and chitosan (1:1 in mass) at pH 5.28, followed by mixing and drying at room temperature. The FTIR spectra, XRD patterns and SEM assay confirmed that alginate-chitosan PEC was obtained. The color change of the BTB indicator proved that urease was trapped in the cavities of the alginate-chitosan PEC membrane while the immobilized urease still showed catalytic activity. Thus, the membrane of alginate-chitosan PEC has good characteristics as a matrix for urease immobilization.
PENDAMPINGAN MASYARAKAT DESA JAGO LOMBOK TENGAH DALAM PEMANFAATAN LIMBAH RUMPUT LAUT SEBAGAI PUPUK Dhony Hermanto; Fahrurazi Fahrurazi; Nurul Ismillayli; Ahmad Wirahadi; Ruru Honiar; I. G. Ayu Sri Andayani; Linda Marta Shofiyana
JMM (Jurnal Masyarakat Mandiri) Vol 4, No 4 (2020): September
Publisher : Universitas Muhammadiyah Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (441.003 KB) | DOI: 10.31764/jmm.v4i4.2072

Abstract

Abstrak: Ketergantungan pada pemakaian pupuk urea yang tinggi mempengaruhi kualitas lingkungan terutama kualitas air permukaan di Desa Jago Kec. Praya Kab. Lombok Tengah. Salah satu alternatif mengurangi ketergantungan tersebut adalah penggunaan pupuk cair organik yang berasal dari limbah rumput laut mengingat melimpahnya rumput laut di Nusa Tenggara Barat. Kegiatan pendampingan masyarakat Desa Jago dalam mengolah limbah rumput laut menjadi pupuk cair telah dilakukan. Introduksi teknologi pengolahan dilakukan menggunakan metode fermentasi atau pengomposan. Mitra sasaran adalah anggota kelompok tani Tunas Harapan, Patuh Angen II, Timbul Jaya. Kegiatan dilakukan dengan mengenalkan manfaat limbah rumput laut sebagai bahan pupuk organik cair dan jenis pupuk berkualitas yang ramah lingkungan. Kemudian dilanjutkan dengan melakukan kerja praktek pengolahan limbah rumput laut melalui fermentasi menggunakan EM4 untuk meningkatkan kualitas pupuk. Hasil kegiatan peningkatan ketrampilan anggota kelompok tani dalam membuat pupuk organik cair yang berkualitas berbahan dasar limbah. Kegiatan ini dapat meningkatkan pemanfaatan limbah rumput laut sekaligus mewujudkan organic farming yang ramah lingkungan dengan tetap mempertahankan produktivitas tanaman pertanian.Abstract: The high dependence on the use of urea fertilizer affects the quality of the environment especially the quality of surface water in Desa Jago Kec. Praya Kab. Lombok Tengah. One alternative to reduce dependence is the use of organic liquid fertilizers derived from seaweed waste given the abundance of seaweed in West Nusa Tenggara. Community service activities in Desa Jago in processing seaweed waste into liquid fertilizer have been carried out. The introduction of processing technology is carried out using the fermentation or composting method. The target partners are members of the Tunas Harapan, Patuh Angen II, Timbul Jaya farmer groups. The activity was carried out by introducing the benefits of seaweed waste as a liquid organic fertilizer and an environmentally friendly type of fertilizer. Then proceed with practical work on processing seaweed waste through fermentation using EM4 to improve fertilizer quality. The results of activities improve the skills of members of farmer groups in making liquid organic fertilizer of high quality based on waste. This activity can increase the utilization of seaweed waste while creating environmentally friendly organic farming for maintaining the productivity of agricultural
PELATIHAN DAN PENDAMPINGAN DEMO INSTRUMENTASI BAGI MAHASISWA SEBAGAI BAGIAN GOOD LABORATORY PRACTICE Dhony Hermanto; Nurul Ismillayli; Ulul Khairi Zuryati; Ruru Honiar; Baiq Mariana; I G. Ayu Sri Andayani
SELAPARANG Jurnal Pengabdian Masyarakat Berkemajuan Vol 5, No 1 (2021): Desember
Publisher : Universitas Muhammadiyah Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31764/jpmb.v5i1.6393

Abstract

ABSTRAKLaboratorium kimia merupakan salah satu jenis laboratorium yang memiliki resiko sangat berbahaya dalam penyelenggaraan pendidikan, penelitian dan/atau pengabdian kepada masyarakat, sehingga laboratorium harus dikelola dan digunakan secara baik dan bijaksana. Pengoperasian peralatan sebagai salah satu aktivitas Good Laboratory Practice (GLP) merupakan aktivitas secara rutin dilakukan di laboratorium kimia. GLP dapat mewujudkan keselamatan kerja di laboratorium dan meminimalisir kerusakan peralatan akibat kesalahan operasi dan pemeliharaan instrumen. Kegiatan pengabdian ini adalah demo peralatan/instrumentasi Laboratorium Kimia Analitik FMIPA–Universitas Mataram. Metode kegiatan yang dilakukan yaitu pelatihan dan pendampingan yang berupa demo peralatan/instrumentasi meliputi kromatografi gas–spektroskopi massa (GC-MS), kromatografi cair kinerja tinggi (KCKT), spektrometer serapan atom (SSA) dan infra merah (FTIR). Kegiatan ini dilakukan untuk meningkatkan keterampilan dasar mitra dalam pengoperasian instrumentasi tersebut. Mitra kegiatan adalah 20 mahasiswa program studi Kimia semester lanjut (5-8). Keberhasilan kegiatan diukur dengan membandingkan skor tes mitra sebelum dan setelah kegiatan dilakukan. Kegiatan pengabdian berlangsung baik dan menghasilkan peningkatan pemahaman serta keterampilan mitra dalam mengoperasikan instrumen yang ditunjukkan dengan peningkatan skor tes mitra. Kegiatan ini diharapkan dapat mewujudkan GLP sehingga kegiatan penelitian dilakukan dengan aman dan efisien. Kata kunci: pelatihan; instrumen; good laboratory practise; mahasiswa. ABSTRACTChemical laboratory is one type of laboratory that has a very dangerous risk in the implementation of education, research and/or community service, so the laboratory must be managed and used properly and wisely. Equipment operation as one of the Good Laboratory Practice (GLP) activities is a routine activity carried out in chemical laboratory. GLP could realize work safety in laboratory and minimize instrument operation and maintenance mistake This community service activity was a demonstration of instrumentation of the Analytical Chemistry Laboratory, FMIPA–University of Mataram. The method of activity carried out are training and assistance in form of instrument demo including gas chromatography–mass spectroscopy (GC-MS), high performance liquid chromatography (HPLC or HPLC), atomic absorption spectrometer (SSA or AAS) and infrared spectrometer (FTIR). This activity is carried to improve basic skill of partner in operating of instruments. The activity partners are 20 students of the advanced semester (5-8th semester) in Departement of Chemistry. The success of activity was measured by comparing the partner’s test score before and after the activity was carried out.The service activity went well and could increase the partners' understanding and skills in operating the instrument. This activity is expected to realize the GLP so that research activities are carried out safely and efficiently. Keywords: training; instrument; good laboratory practice; student.
Co-Authors Ahmad Wirahadi Ahmad Wirahadi Alya Hadranita Utami Amida Rischia Ulfa Anjarwati, Aprilia Apriana, Dita Apriani, Niza Yusnita Baiq Anggi Yustika Leni Baiq Handayani Rinuastuti Baiq Mariana Baiq Mariana Bambang Kuswandi Bambang Kuswandi Bambang Kuswandi Bambang Kuswandi Bela Azkiana Chen, Chang-Nan Datin An Nisa Sukmawati Dedi Suhendra Dedy Suhendra Dedy Suhendra Dina Asnawati Dwi Siswanta Dwi Siswanta Dwi Siswanta Elfred Rinaldo Kasimo, Elfred Rinaldo Erin Ryantin Gunawan Erin Ryantin Gunawan Erin Ryantin Gunawan Erin Ryantin Gunawan Erin Ryantin Gunawan, Erin Fahrurazi Fahrurazi Fahrurazi Fahrurazi Fahrurazi Fahrurazi Fahrurazi Fahrurazi Handa Muliasari I G. Ayu Sri Andayani I. G. A. Sri Andayani I. G. Ayu Sri Andayani Iman Rahayu Iman Rahayu Hidayati Soesanto Iriando, Mahadi Muhammad Gunadharma Iwan Sumarlan Juliandri Juliandri Juliandri Jurnal Pepadu Laili Mardiana Lalu Agung Nartiadi Lely Kurniawati Lely kurniawati Liliek Karnila Linda Marta Shofiyana Linda Marta Shofiyana Lisa Savitri Mamika Ujianita Romdhini Mamika Ujianita Romdhini, Mamika Ujianita Mariana, Baiq Marliadi Susanto Masyhuri, Aga Adi Mudasir Mudasir Mudasir Mudasir Mudasir Mudasir Mudasir Mudasir Muhammad Zakirrahman Murniati Murniati Murniati . Murniati Murniati Muttaqin, Saiful Ni Kadek Intan Wulan Sinta Dewi Nindi Herdiyanti Nurlaela Nurlaela Nurul Ismillayli Prihatini, Putri Jauhar Qurnia Aini Rasyadan Taufiq Probojati Rina Kurnianingsih RINA KURNIANINGSIH Rochmad K Sanjaya Rochmad K. Sanjaya Rochmad Kris Sanjaya Rochmad Krissanjaya Rosita Wati Ruru Honiar Ruru Honiar Ruru Honiar Sanjaya, Rochmad K Saprini Hamdiani Saprizal Hadisaputra Saputri, Dinar Suksmayu Sari, Ayu Purnama Sawmi Jannaturrayyan Siti Raudhatul Kamali Siti Raudhatul Kamali Siti Raudhatul Kamali Soraya Aulia Sri Seno Handayani Sri Seno Handayani Sri Seno Handayani Sri Seno Handayani Sudirman Sudirman Surya Hadi TATI NURHAYATI Ulul Khairi Zuryati Ulul Khairi Zuryati Ulul Khairi Zuryati Ulul Khairi Zuryati Ulul Khairi Zuryati Ulul Khairi Zuryati Wirahadi, Ahmad Yuliasari, Rina