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ALCHEMY Jurnal Penelitian Kimia
Published by Universitas Sebelas Maret
ISSN : 14124092     EISSN : 24434183     DOI : -
Core Subject : Science, Social, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Environmental Science Materials Science & Nanotechnology
ALCHEMY Jurnal Penelitian Kimia is a chemistry journal published by Sebelas Maret University, Surakarta. ALCHEMY Jurnal Penelitian Kimia publishes original research articles or review articles in organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, biochemistry, and environmental chemistry.
Arjuna Subject : -
Articles 285 Documents
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An Empirical Study on The Hydrogen Peroxide Reaction with Iodide in Acid Condition Ayuni Dita Rosalia; Patiha Patiha; Eddy Heraldy
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 1 (2015): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.1.109.72-80

Abstract

This research aimed to find out I- reaction order in the mechanism of  hydrogen peroxide reaction with iodide in acid condition, to find out the form of rate law, and to show the role of H+ in reaction. The experiment for determining reaction order was carried out with isolation method using UV-Vis spectrophotometry. The order reaction was obtained from the r value approaching one, the results of its linear regression. The form of rate law was viewed from the presence or absence of oxygen gas. Meanwhile the role of H+ in reaction was determined by observing the pH value in 60 minutes.The result of experiment shows that the mechanism of reaction has rate law in the form of fraction, in which I- could be in zero and first orders. In addition, the rate law in this experimental condition is not an addition in the absence of O2 and relatively equal kobs value in the same order. The role of H+ is observed not as catalyst, but reactant.
The Development of Conductometric Biosensor for Determination of Uric Acid Concentration in Human Serum Using Screen Printed Carbon Electrode (SPCE) – Nata De Coco Abdi Naufal Ramadhan; Luluil Maknun; Noerma Juli Azhari
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 2 (2015): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.2.724.192-199

Abstract

The control of uric acid is important. A high level of uric acid can cause gout disease. Therefore a simple, fast, and accurate method for uric acid determination is required. In this research a conductometric biosensor has been developed by SPCE – Nata de coco for uric acid determination. The prepared biosensor was optimized to get a good performance of biosensor and it is applicable for human serum samples. The optimized variables were enzyme concentration, membrane thickness and pH solution. The various enzyme concentration were 6 μg/mL; 12 μg/mL; 18μg/mL; 24 μg/mL. The various membrane thickness were 5 μm; 10 μm; 15 μm. Meanwhile, the various pH solution were 7; 7.5; 8; 8.5; 9. The optimum enzime concentration was 18 µg/mL with the membrane thickness and pH were 5 µm and 8, respectively. The prepared biosensor can determine the uric acid concentration at range of 0 – 1.2 ppm with the sensitivity of 7.74 µS/ppm and the limit detection is 0 ppm. The biosensor was applied to uric acid detection in human serum with accuracy of 95 %.
Microbial Fuel Cell Based Polystyrene Sulfonated Membrane as Proton Exchange Membrane S Muljani; A Wulanawati
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 2 (2016): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.2.1818.155-166

Abstract

Microbial fuel cell (MFC) represents a major bioelectrochemical system that converts biomass spontaneously into electricity through the activity of microorganisms. The MFC consists of anode and cathode compartments. Microorganisms in MFC liberate electrons while the electron donor is consumed. The produced electron is transmitted to the anode surface, but the generated protons must pass through the proton exchange membrane (PEM) to reach the cathode compartment. PEM, as a key factor, affects electricity generation in MFCs. The study attempted to investigate if the sulfonated polystyrene (SPS) membrane can be used as a PEM in the application on MFC. SPS membrane has been characterized using Fourier transform infrared spectrophotometer (FTIR), scanning electron microscope (SEM) and conductivity.  The result of the conductivity (σ) revealed that the membrane has a promising application for MFC.
SURFACE CHARACTER OF IRON OXIDE/CARBON NANOPARTICLES SYNTHESIZED BY SUBMERGED ARC DISCHARGE METHOD IN ETHANOL/UREA MEDIUM Teguh Endah Saraswati; Fitri Nela Sari; Nestri Handayani
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 2 (2017): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.2.2392.287-297

Abstract

Synthesis of iron oxide nanoparticles modified with carbon has been successfully performed by submerged arc-discharge method in ethanol/urea medium. Iron oxide used in the fabrication process was prepared by iron electrolysis in an electrolyte solution of NaCl. Fabrication of nanoparticles in this method uses two graphite electrodes. One of them was made in a pointed shape and the other graphite electrodes hollowed out and filled with a mixture of iron oxide, graphite and glue silica (as binder) with a ratio of 1:3:1 (w/w/w). The liquid medium used in this method is a mixture solution of ethanol 50% and urea (0%, 10%, 25% and 50%) with a volume ratio of 1:1 (v/v). The crystalline of iron oxide was characterized using X-Ray Diffraction (XRD), compared to JCPDS No. 89-0597, No. 89-0691 and No. 39-1346. Variations in the urea concentration in the liquid medium provided the changes of the surface character of the synthesized nanoparticles. The changes of surface character were analyzed by the Fourier Transform Infra Red (FTIR) spectra and nanoparticle dispersion in water and ethanol. FTIR spectra showed the absorption of Fe-O, CH, CN, C = O, OH and NH at 460-555 cm-1, 650-1000 cm-1, 1000-1350 cm-1, 1640-1680 cm-1, 2400-3400 cm-1, 3200-3400 cm-1, 3100-3500 cm-1, respectively. The best hydrophilic surface character achieved when the nanoparticle was synthesized in medium of ethanol 50% with the addition of urea50%. The existence of a functional group attached on the surface of nanoparticles synthesized in ethanol/urea makes these nanoparticles had better dispersion than nanoparticles synthesized in ethanol medium without urea addition.
Identification of 4-4’-(1-methylethylidene)-bisphenol from an Endophytic Fungus Cladosporium oxysporum derived from Aglaia odorata Armila Fatma Setyaningrum; Risma Pratiwi; Suciati Suciati; Noor Erma Nasution Sugijanto; Gunawan Indrayanto
ALCHEMY Jurnal Penelitian Kimia Vol 14, No 2 (2018): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.14.2.12974.193-201

Abstract

Endophytic fungi has an economic potential as raw material for biologically active compounds. Cladosporium oxysporum is one of the endophytic fungi isolated from Indonesian medicinal plant Aglaia odorata Lour (Local name: Pacarcina). This planth has been used for fever, cough, diarrhea, inflammation and injury. In our previous study, the ethyl acetate extract and several fractions of the extract of C. oxysporum showed antimicrobial activity against Candida albicans, Escherichia coli, and Staphylococcus aureus. The objective of the currents study is to investigate the chemical constituent of the active fraction. Purification of the metabolite was achieved by using column chromatography followed by preparative thin layer chromatography. Identification of the metabolite was conducted by using TLC densitometry, GC-FID and GC-MS. Compound 1 was isolated from fraction 12. The purity of this compound was determined by 2D-TLC and GC-FID. The UV-Vis profile of compound 1 indicates a phenolic compound. Further analysis by using GC-MS shows one peak at a retention time (Rt) of 23.80 minutes, predicted as 4-4’-(1-methylethylidene)-bisphenol. The chemical constituent of the sub fraction 12.2.7 (fraction a) is identified as 4-4’-(1-methylethylidene)-bisphenol.
Characteristics of Chlorella sp Biomass Immobilized on Chitosan (Chlo-Kit) for Adsorption of Chromium(III) Solution Titin Anita Zaharah; Anis Shofiyani; Endah Sayekti
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 1 (2015): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.1.102.15-28

Abstract

Properties of biosorbent prepared from biomass of Chlorella sp immobilized on chitosan (Chlo-Kit) have been studied for adsorption of Chromium(III). Chlo-Kit adsorbent prepared by following steps: dissolving chitosan to get hydrogel form, immobilization of biomasson chitosan hydrogel, beads formation and crosslinkingthe adsorbent beads using epichlorohydrin reagent.Characterization using FT-IR spectrophotometry  and SEM showed that mechanism of biomass immobilization on chitosan involves electrostatic interactions between the functional groups of such both materials. Biomass immobilized on chitosan (Chlo-Kit) showed the higher stability in acid medium than un-immobilized biomass. Adsorption of Cr(III) metal ion on Chlo-Kit occured at optimum pH of 4-5 and followed well the Langmuir adsorption isotherm model. The adsorption capacity of Cr(III) on Chlo-Kit was 68.965 mg/g, about 91% higher than that on Chlorella biomass
The Paraffin Cracking Reaction with NiMo/Active Natural Zeolite Catalyst: The Effect Temperature on Catalytic Activity Khoirina Dwi Nugrahaningtyas; Eko Cahyono; Dian Maruto Widjonarko
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 2 (2015): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.2.712.111-126

Abstract

This research deals with the study of the paraffin cracking reaction with termal reaction, active natural zeolite (ZAA) and NiMo / active natural zeolite (ZAA) catalyst. Temperature variation was done in order to study the optimum temperature of paraffin cracking reactions. Paraffin cracking reaction carried out at temperatures of 200 - 400 °C and a hydrogen flow rate of 30 mL / min. Cracking products obtained, and then analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry(GCMS). Catalyst activity (%) was defined as the amount of lighter fractions/the amount of feed (paraffin) (%). The results showed that the catalyst NiMo/ZAA has the highest activity (31.33 %) at the cracking reaction temperature of 300 ºC
ANTI-HYPERCHOLESTEROLEMIA ACTIVITY OF ETHANOL EXTRACT Peperomia pellucid Chasanah Mazroatul; Glar Donia Deni; Nur Ahmad Habibi; Gita Febri Saputri
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 1 (2016): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.1.948.88-94

Abstract

Hypercholesterolemia is a major cause of cardiovascular disease such as coronary heart disease. Betel water (Peperomia pellucida) is a type of plants that have antioxidant compounds that could delay, retard and prevent the oxidation of lipids, both enzymatic and non-enzymatic. This study aimed to determine the effect of ethanol extract Peperomia pellucida against total cholesterol, HDL, LDL, and triglycerides in the serum of white rats (Wistar) were given a diet aterogenetik, so it can be used as prevention of atherosclerosis. The active compounds contained in the water after screnning betel phytochemicals includes flavonoids, tannins, alkaloids, steroids and quinones. In vivo studies conducted by true experimental method with pre and post test with control group design. Rats were divided into 3 groups: group A positive control is given aterogenetik diet, group B and C were given diet Peperomia Pellucida aterogenetik and extract orally at a dose of 150 mg/kg and 300 mg/kg. Diet aterogenetik given as much as 20 grams per day for 14 days. Data obtained include total cholesterol, HDL, LDL, and triglycerides were analyzed by statistical methods Paired T Test oneway ANOVA (P < 0.05). The study of total cholesterol, HDL, LDL and triglycerides showed ethanol extract of Peperomia pellucida at a dose of 300 mg/kg body weight can lower total cholesterol and LDL significantly, but there was no significant decline in triglycerides and can increase HDL levels.
SYNTHESIS OF CHITOSAN-FILM COMPOSITE TiO2 USING SORBITOL AS PLASTICIZER Imelda Fajriati; Endaruji Sedyadi; Sudarlin Sudarlin
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 1 (2017): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.1.4350.75-94

Abstract

The synthesis of chitosan–TiO2 film composite using sorbitol as plasticizer has been conducted. This research aims to develop environmental friendly plastic material which is safe for health due to the use of biodegradable chitosan - TiO2 that can block UV rays and therefore, maintain the quality of product from damage caused by UV rays. The anatase phase TiO2 nanocrystal was synthesized in chitosan matrix at room temperature and aging process. The solution was then added and blended in sorbitol for 24 hours to obtain homogeneous solution. The composite film was formed by coating method on a plate substrate, followed by drying. The characterization of film composite by XRD, TEM and FTIR showed the forming of anatase phase TiO2 nanocrystal that dispersed in chitosan matrix and formed the hydrogen bond. Meanwhile, from the physical properties characterization it was observed that the use of sorbitol as plasticizer had improved the plasticity tensile strength and elongation of the composite film. However, the excess sorbitol reduced the elasticity, tensile strength and elongation of the plastic. The best quality of plasticity obtained from film composite added by 3 % of sorbitol.
ANALITICAL METHOD VALIDATION OF ANIONIC SURFACTANT SODIUM DODECYL BENZENE SULFONATE (SDBS) IN CATFISH BY UV-VIS SPECTROPHOTOMETRY USING ACRIDINE ORANGE Monica Cahyaning Ratri; Adhitasari Suratman; Roto Roto
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 2 (2017): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.2.8916.145-165

Abstract

The analytical method development on an anionic surfactant of sodium dodecylbenzenesulfonate (SDBS) in a catfish using spectrophotometer UV-Vis using acridine orange (AO) has been conducted. This research aims to determine the optimum conditions of analysis and to determine validation parameters of sodium dodecylbenzenesulfonate (SDBS) analysis in a catfish. This study was divided into two steps, isolation of sodium dodecyl benzene sulfonate (SDBS) in the catfish with soxhlet extraction and the analysis of SDBS. The analysis of sodium dodecylbenzenesulfonate (SDBS) is based on the formation of ion pair between dodecylbenzenesulfonate (DBS) and acridine orange (AO). The results showed that the analysis can be performed at 499 nm, using ethanol as acridine orange (AO) solvent, the mole ratio of dodecylbenzenesulfonate (DBS) acridine orange (AO) 2:1, and pH 2.97. The parameters of validation had good acceptability as linearity (r) 0.998, limit of detection 0.0343 mg/L   and limit of quantification 0.104 mg/L, precision 0.382 - 1.78 %, sensitivity 4.64 x 104 L mol-1cm-1, and accuracy (82.11 - 100.3 %).

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