248 results
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Preservation of Natural Colorant Extract of Jalawe Fruit Peel (Terminalia bellirica) in Water-Based Solution
The general objective of this study is to preserve natural colorant extract of jalawe fruit peel in water-based solution during storing. The specific objectives in this research are finding suitable type and amount of antimicrobial compound to prevent biological degradation of the natural colorant…
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Comparative Study on the Adsorption of [AuCl4]– onto Salicylic Acid and Gallic Acid Modified Magnetite Particles
Salicylic acid-modified magnetite (Mag-SA) and gallic acid-modified magnetite (Mag-GA) particles were prepared by co-precipitation procedure. Characterization results showed the interaction that occurs between the surface of magnetite with salicylic acid (Mag-SA) and gallic acid (Mag-GA) was…
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Improvement of Student Critical Thinking Skills with the Natural Product Mini Project Laboratory Learning
This research aims to investigate effect of learning using natural product mini project laboratory on students’ critical thinking skills. The research was conducted on sixth semester of 59 students of chemistry and chemistry education program from one of the state universities in West Nusa…
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Evaluation of Lagergren Kinetics Equation by Using Novel Kinetics Expression of Sorption of Zn2+ onto Horse Dung Humic Acid (HD-HA)
Extraction and purification of humic acid from dry horse dung powder (HD-HA) was performed successfully and the purified HD-HA was then applied as sorbent to adsorb Zn2+. Extraction and purification were performed based on procedure of Stevenson (1994) under atmospheric air. Parameters investigated…
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Photocatalytic and Photoelectrocatalytic Degradation of Methyl Orange Using Graphite/PbTiO3 Composite
Synthesis of graphite/PbTiO3 composite as a catalyst in photodegradation and photoelectrodegradation process of methyl orange have been conducted. The purposes of this research are to study the effect of radiation time, composition of composite, voltage and pH of solution for methyl orange…
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Synthesis of ZnO Nanoparticles by Precipitation Method with Their Antibacterial Effect
The aim of this study was to synthesize and characterize Zinc oxide nanoparticles (ZnO-NPs) prepared by precipitation method. Zinc nitrate and sodium hydroxide was used as starting materials with biopolymer pectin as capping agent. ZnO-NPs were synthesized at three levels of temperatures (60, 80…
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Influences of Temperature on the Conversion of Ammonium Tungstate Pentahydrate to Tungsten Oxide Particles with Controllable Sizes, Crystallinities, and Physical Properties
The purpose of this study was to investigate influences of temperature on the conversion of ammonium tungstate pentahydrate (ATP) powder to tungsten trioxide (WO3) particles with controllable sizes, crystallinities, and physicochemical properties. In this study, we used a simple thermal…
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Functionalization of Fe3O4/SiO2 with N-(2-Aminoethyl)-3-aminopropyl for Sorption of [AuCl4]-
Synthesis of Fe3O4/SiO2 modified with N-(2-aminoethyl)-3-aminopropyl group (Fe3O4/SiO2/ED) via coating method and its application for adsorption-desorption of anionic gold in aqueous solution have been conducted. The synthesized product was characterized with an X-ray diffractometer (XRD), a…
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Hydrothermal Transformation of Natural Zeolite from Ende-NTT and Its Application as Adsorbent of Cationic Dye
A synthetic zeolite was produced from natural zeolite from Ende-Nusa Tenggara Timur (NTT) by hydrothermal method. This study aims to produce synthetic zeolite from Ende natural zeolite to remove cation dye through the adsorption process. Temperature of crystal formation (ageing) was performed at 60…
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Preparation of Citric Acid Crosslinked Chitosan/Poly(Vinyl Alcohol) Blend Membranes for Creatinine Transport
Preparation of membrane using crosslinking reaction between chitosan and citric acid showed that functional group modification increased the number of active carrier groups which lead to better transport capacity of the membrane. In addition, the substitution of the carboxyl group increased…
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New Prenylated Stilbenes and Antioxidant Activities of Cajanus cajan (L.) Millsp. (Pigeon pea)
New Prenylated stilbene derivatives, 3-hydroxy-4-prenyl-5-methoxy-stilbene acid (1) and 5,4'-dihydroxy-3-methoxy-2-prenyl-stilbene (2) had been isolated from methanol extract of Cajanus cajan (L.) Millsp. (Pigeon pea), a member of family fabaceae. The aim of this present work was to evaluate its in…
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The Phenolic Compound from Kalanchoe blossfeldiana (Crassulaceae) Leaf and Its Antiplasmodial Activity against Plasmodium falciparum 3D7
Various species of Kalanchoe plants have been widely used as raw materials in traditional medicines. This study was the continuation of the researches on secondary metabolites from Indonesia Kalanchoe plants, focused on Kalanchoe blossfeldiana. Fresh K. blossfeldiana leaf was extracted with…
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Chemical Composition, Phytochemical Screening and Antioxidant Activity of Acmella uliginosa (Sw.) Cass Leaves
Acmella uliginosa (Sw.) Cass is widely used in traditional medicine and used in the treatment of many diseases. Extraction of component in leaves of Acmella uliginosa used methanol, ethyl acetate and n-hexane solvent. The percentage yield of extract from the leaves in methanol, ethyl acetate and…
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Oxidation of Cyclohexane to Cylohexanol and Cyclohexanone Over H4[a-SiW12O40]/TiO2 Catalyst
Oxidation of cyclohexane to cyclohexanol and cyclohexanone was carried out using H4[a-SiW12O40]/TiO2 as catalyst. In the first experiment, catalyst H4[a-SiW12O40]/TiO2 was synthesized and characterized using FTIR spectroscopy and X-Ray analysis. In the second experiment, catalyst…
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Utilization of Cellulose from Pineapple Leaf Fibers as Nanofiller in Polyvinyl Alcohol-Based Film
Cellulose from pineapple leaf fibers as one of the natural polymer which has biodegradable property in a nanometer’s scale, can be formed as a filler in composite of Poly(vinyl) Alcohol/PVA is expected to increase the physical, thermal, and barrier properties of composite films similar to…
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Quantification of Andrographolide Isolated from Andrographis paniculata Nees Obtained from Traditional Market in Yogyakarta Using Validated HPLC
This research was aimed to quantification of andrographolide isolated from A. paniculata Ness found in traditional market in Yogyakarta using validated HPLC to obtain high level content of andrographolide. The extraction of andrographolide from A. paniculata was carried out using ethanol as the…
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Synthesis and Characterization of Oligomer 4-Vinylpyridine as A Corrosion Inhibitor for Mild Steel in CO2 Saturated Brine Solution
In this work, the oligomer of 4-vinylpyridine designated as O(4-VP) was synthesized by hydrogen peroxide initiated chain growth polymerization and characterized in terms of molecular weight and structure by matrix assisted laser desorption ionization time of flight mass spectroscopy (MALDI-TOF MS)…
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Calcium Oxide from Limestone as Solid Base Catalyst in Transesterification of Reutealis trisperma Oil
CaO catalysts were synthesized from limestone by thermal decomposition and coprecipitation methods. The CaO and MgO reference catalysts were also synthesized for comparison. The catalysts were characterized by X-ray diffractometer (XRD) and the analysis result was refined by Rietica software. CaO…
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Thermodynamic and Kinetic Study of Zinc bis-(Dipalmithyl Dithiophosphate) Activity as Anti-Corrosion Additive-Fatty Acid Based Through Potentiodynamic Polarization Technique
Zinc bis-(dipalmithyl dithiophosphate) (ZDTP16) is one product variant of zinc dialkyl dithiophosphate (ZDTP)-fatty acid based having function as corrosion inhibitor. By using 3% of effective dose for the application, its effectiveness of ZDTP16 corrosion inhibition will achieve 97% and it will be…
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Molecular Dynamics Simulations and Empirical Observations on Soy Lecithin Liposome Preparation
Soy lecithin is a phospholipid often used in liposome formulations. Determination of water and phospholipid composition is one of the problems in the liposome formulation. This study is using molecular dynamics simulation and empirical observation in producing liposome preparations. Phospholipids…