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All Journal Jurnal VOK@SINDO The Journal of Pure and Applied Chemistry Research Jurnal Penelitian Pendidikan IPA (JPPIPA) Jurnal Sistem Teknik Industri Molekul: Jurnal Ilmiah Kimia International Journal of Renewable Energy Development
Ulfa Andayani, Ulfa
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Agriculture, Biological Sciences & Forestry Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Education Electrical & Electronics Engineering Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology Medicine & Pharmacology Physics Social Sciences Other

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Identifikasi Limbah pada Proses Produksi Obat Nyamuk Bakar dengan Menggunakan Material Balance Sitepu, Muhamad Haikal; Andayani, Ulfa; Alda, Tania
Jurnal Sistem Teknik Industri Vol. 22 No. 2 (2020): JSTI Volume 22 Number 2 July 2020
Publisher : TALENTA Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jsti.v22i2.3935

Abstract

Based on the initial discussion with people form Mosquito coil factory, there is a requirement to calculate the amount of waste from the factory. According to them, several wastes (in the form of liquid and solid waste) are produced in the process of making mosquito coils. The wastes are often scattered on the floor, causing the condition of the factory space to be unclean or dirty and can cause employees to get sick due to waste scattered on the floor. This research focuses on identifying the waste and to calculate the waste produced by each machine for the production of mosquito coils by using the Material Balance method. Material balance shows a quantitative analysis of material inputs, outputs and wastes / waste at each stage of the production process. Material balance calculation is done in the process of Sifting Coconut Shell Flour, Sifting Process for Coffee Skin Flour, Process for Sifting Wood Flour, Sifting Flour Sifting Process, Onggok Flour Cooking Process, Mixing Material into Mosquito Coe Dough, Mosquito Dough Sifting Process, Forming Process of Paste Paste Plate , The Process of Printing Paste Slabs Into Wet Double Coil, Drying Double Wet Coil Process, Drying and Separation Process of Baking Sheet with Dry Double Coil, Grinding Process of Broken Dry Double Coil, Process of Sifting Sweep Flour Falling on the Floor. Based on the observation, some of the waste obtained from each stage of the production process can be collected again and can be used again as a raw material for making mosquito coils.
In situ Measurement of Phosphate using Fe3O4/Chelex®100-Agarose-Oxalic Acid Hydrogel in Diffusive Gradient in Thin Films Dinira, Layta; Rumhayati, Barlah; Mardiana, Diah; Andayani, Ulfa
Molekul Vol 19 No 2 (2024)
Publisher : Universitas Jenderal Soedirman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.jm.2024.19.2.11199

Abstract

ABSTRACT. This study would be the first to develop a novel combination of Chelex®100 and Fe3O4 as a mixed binding gel for in situ phosphate measurement employing Diffusive Gradient in Thin Films (DGT). Fe3O4 and Chelex®100 were utilized as binding agents within a single binding layer for phosphate measurements in laboratory and natural water settings. The synthesized Fe3O4 was identified as magnetite and consisted of micro-sized particles. The pore size of the mixed binding gel ranged from 22.39 to 112.5 µm. Incorporating Chelex®100 with Fe3O4 in oxalic acid cross-linked agarose did not diminish phosphate adsorption efficiency. As adsorption time and phosphate concentration in solution increased, the quantity of adsorbed phosphate in the mixed binding gel also increased. Optimal phosphate elution was achieved using a basic solution, with a phosphate elution efficiency of 95.3 ± 0.4% observed with 0.4 M NaOH. The diffusion coefficient measured using the mixed binding gel was 1.08 times greater than that of polyacrylamide cross-linked with an agarose derivative (APA) gel, typically employed in the DGT technique. Phosphate concentration measurement with Fe3O4/Chelex®100-agarose oxalic acid in a DGT passive sampler at pH 4-8 yielded values twice those in bulk solution. Similar results were obtained when measuring phosphate in a 0.01 – 0.1 M NaNO3 solution. A T-test showed that the phosphate concentration obtained from mixed binding layer-DGT as an alternate passive sampler was not significantly different from grab sampling. This study underscores the suitability of Fe3O4-Chelex®100 impregnated in agarose-oxalic acid gel for monitoring phosphate in natural water via DGT. Keywords: Agarose, diffusive gradient in thin films, mixed binding gel Fe3O4, oxalic acid.
ANALISIS STRATEGI ROOM ATTENDANT DALAM MENANGANI COMPLAINT TAMU DI HOTEL SOFYAN CUT MEUTIA MENTENG JAKARTA Aliffanza, Gema Irfan; Andayani, Ulfa; Irmawati, Dini Kurnia
VOK@SINDO : Jurnal Ilmu-Ilmu Terapan dan Hasil Karya Nyata Vol. 10 No. 2 (2022)
Publisher : Fakultas Vokasi Universitas Brawijaya

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Abstract

Dalam kegiatan operasional hotel sehari – hari tidak luput dari tamu yang memberikan complaint terhadap hotel, Hal tersebut juga terjadi pada room attendant. Terbukti masih adanya karyawan room attendant yang menjalankan tugasnya yang belum maksimal dan tidak menjalankan SOP darihotel sehingga masih adanya tamu yang memberikan complaint di Hotel Sofyan Cut Meutia Menteng Jakarta. Tujuan dari penelitian ini adalah untuk mengetahui bagaimana strategi yang dilakukan room attendant dalam menangani complaint tamu di Hotel Sofyan Cut Meutia Menteng Jenis penelitianyang digunakan dalam penelitian ini adalah penelitian kualitatif deskriptif dengan pengumpulan data menggunakan metode wawancara, angket dan dokumentasi. Selanjutnya data dianalisis menggunakan teknik, penyajian data, redukisi data, dan penarikan kesimpulan. Hasil penelitian ini ditemukan terjadinya complaint dari tamu yang di sebabkan dari faktorfaktor pendorong terjadinya complaint dari tamu. Perlunya room attendant membuat strategi dalam menangani complaint tamu agar para karyawan room attendant dapat menjalankan tugasnya dengan maksimal, sehingga tamu merasa puas dan tidak memberikan complaint di Hotel Sofyan Cut Meutia Menteng Jakarta 
Synthesis of Chitosan Magnetic Nanoparticles using Glutaraldehyde and Tripolyphosphate as Crosslinker Rahmani, Indri Alidha; Mulyasuryani, Ani; Andayani, Ulfa
The Journal of Pure and Applied Chemistry Research Vol. 11 No. 2 (2022): Edition May-August 2022
Publisher : Chemistry Department, The University of Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jpacr.%y.011.02.683

Abstract

Chitosan is an abundant natural polymer, which able to adsorb Pb2+. However, chitosan has the drawback of being unstable in acid and alkaline conditions, so it needs cross-linking. In this article, we will compare the usage of two crosslinkers, glutaraldehyde (GD) and tripolyphosphate (TPP), to solve these issues. The synthesis of chitosan magnetic nanoparticles was carried out by co-precipitation with the addition of glutaraldehyde under acidic conditions and the addition of TPP under alkaline conditions. The results showed that the FTIR spectrum gave characteristic bands at 3131.96 cm-1 (OH and NH), 1635.86 cm-1 (C=O), 1401.97 cm-1 (CN), ~1110 cm-1 (COC), and ~617 cm-1 (Fe-O). SEM analysis showed that the surface morphology of CMNP-GD particle aggregation was clear more than that of CMNP-TPP. The size of the synthesized nanoparticles was determined by PSA analysis, which was 131.95 µm and 137.10 µm, respectively. The results of the XRD analysis showed that, in addition to the Fe3O4 and chitosan phases, the produced CMNP also contained γ-Fe2O3 phase, which was considered to be caused by Fe3O4 oxidation. Keywords: nanoparticle, chitosan, magnetic, glutaraldehyde, tripolyphosphate
Aluminum, nickel, and manganese supported on bentonite for conversion of ethanol to gasoline Rahmanda, Deri; Wardhani, Sri; Andayani, Ulfa; Widjaya, Robert R.; Dwiatmoko, Adid A.; Rinaldi, Nino; Prasetyo, Joni; Kurniawan, Kezia F.
International Journal of Renewable Energy Development Vol 14, No 2 (2025): March 2025
Publisher : Center of Biomass & Renewable Energy (CBIORE)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.61435/ijred.2025.60834

Abstract

The potential of bentonite as a catalyst is rapidly growing, isomorphic substitution in its interlayer allows for cation exchange and facilitates modification to enhance its catalytic properties. The catalytic performance of bentonite can be improved through the insertion of pillared clays (PILC) into its interlayer structure using Al2O3, NiO, and MnO metal oxide alloys. This research aims to develop and study a modified bentonite catalyst, focusing on its physicochemical changes,as well as its activity and selectivity in the conversion of ethanol to biogasoline. The synthesis of oxide pillars on bentonite was carried out at a consistent metal/bentonite mole ratio of 10 mmol/g, with a mixed metal composition of 1:1. The results showed anexpansion of interlayer distance, as measured by X-ray diffraction (XRD), which increased in all catalysts compared to natural bentonite6,350 (13.94 Å). Surface Area Analyzer (SAA) analysis, revealed that Al/Bentonite exhibited the highest surface area at187.84 m2/g. Total acidity  analyzed, using Temperature Programmed Desorption-Ammonia (TPD-NH3), was found to be 2.33 mmol/g, with Al-Ni/Bentonite showing the highest acidity. Thermal stability, tested throughThermogravimetric Analysis (TGA), indicated that catalysts containing Al and Ni demonstrated the highest stability. The catalytic activity test showed that the Al/bentonite catalyst achieved the highest ethanol conversion rate of68.64% and a catalyst selectivity of 51.70%, as determined byGas Chromatography-Flame Ionized Detector (GC-FID) analysis. These results indicate that the pillarization of bentonite with Al2O3, NiO, and MnO oxides significantly improved its physicochemical properties, activity, and selectivity in the catalytic conversion of ethanol to biogasoline compared to natural bentonite.
Koefisien Difusi Ion Fosfat dalam Gel Asam Sitrat-Agarosa yang Digunakan dalam Gradien Difusif pada Sampler Pasif Film Tipis (DGT) An-Nufuus, Digwanggi Arum Tazkiyatu; Rumhayati, Barlah; Fardiyah, Qonitah; Mardiana, Diah; Andayani, Ulfa; Dinira, Layta
Jurnal Penelitian Pendidikan IPA Vol 9 No 8 (2023): August
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v9i8.3593

Abstract

In this research, the diffusion coefficient of phosphate ions in agarose-citric acid diffusive gel has been studied. The agarose-citric acid diffusion layer was prepared by mixing 1.5% agarose solution with the addition of citric acid solutions at various concentration. The diffusive gel was casted between two glass plates which were separated using a spacer of 0.1 cm thickness and clamped together in the three sides. Gel was formed for 15 minutes in an oven at 40oC. The diffusion coefficient then was calculated using Fick's First law formula. Gel that produced with addition of 0.45% citric acid absorbed more water during immersion in water for 3 hours for facilitating phosphate diffusion. Swelling degree of the agarose citric acid diffusive gels was not affected by the storing solution condition either in water or in NaNO3 0.1 M. Coefficient diffusion of phosphate in the agarose-citric acid diffusive gel was 1.009×10-7 cm2s-1, less than the diffusion in the pure agarose gel 1.367×10-7 cm2s-1. The diffusion is affected by the ionic strength of solution. Phosphate diffusion coefficient is higher in the phosphate solution with addition of 2 mgL-1 nitrate. Increasing the ionic strength causes lower phosphate diffusion coefficient because the electrostatic attractive and repulsive force
Co-Authors Aliffanza, Gema Irfan An-Nufuus, Digwanggi Arum Tazkiyatu Ani Mulyasuryani Barlah Rumhayati Diah Mardiana Dwiatmoko, Adid A. Irmawati, Dini Kurnia Joni Prasetyo, Joni Kurniawan, Kezia F. Layta Dinira Nino Rinaldi Qonitah Fardiyah Rahmanda, Deri Rahmani, Indri Alidha Sitepu, Muhamad Haikal Sri Wardhani Tania Alda Widjaya, Robert R.