Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

Indonesian Journal of Chemistry

ijc
Website

Published by Universitas Gadjah Mada

ISSN : 14119420 EISSN : 24601578 DOI : -

Core Subject : Science, Engineering,

Chemical Engineering, Chemistry & Bioengineering Chemistry

Indonesian Journal of Chemistry is an International, peer-reviewed, open access journal that publishes original research articles, review articles, as well as short communication in all areas of chemistry including applied chemistry. The journal is accredited by The Ministry of Research, Technology and Higher Education (RISTEKDIKTI) No : 21/E/KPT/2018 (in First Rank) and indexed in Scopus since 2012. Since 2018 (Volume 18), Indonesian Journal of Chemistry publish four issues (numbers) annually (February, May, August and November).

Arjuna Subject : -

Articles 1,956 Documents

116 117 118 119 120

Synthesis and Characterization of Controlled-Release Urea Fertilizer from Superabsorbent Hydrogels Salih Muharam; Afria Fitri; Lela Mukmilah Yuningsih; Yulia Mariana Tessa Ayudia Putri; Isnaini Rahmawati
Indonesian Journal of Chemistry Vol 20, No 3 (2020)
Publisher : Universitas Gadjah Mada

It is very important to develop controlled-release fertilizers to ensure efficiency and environmental protection. This study aims to make a superabsorbent hydrogel-based controlled-release urea fertilizer. Superabsorbent hydrogels were prepared from the cellulose of corn cobs cross-linking with epichlorohydrin, and then an amount of urea as a fertilizer was stored inside the hydrogels (GEL-A). The GEL-A functionalization with carboxy-methyl was also carried out in this study to improve the hydrophilicity of hydrogels (GEL-B). GEL-A and GEL-B were immersed in water at a certain pH and temperature range and the urea concentration released from the hydrogels was monitored by a spectrophotometer. The results showed that the urea released by GEL-A and GEL-B was not much different. Respectively, the urea efficiency of GEL-A and GEL-Bwas around 5.29% and 5.56% for 180 min. The urea released from both hydrogels was not significantly affected by changes in the temperature of the solution. Urea release was influenced by pH, and the rate of urea release of GEL-B was faster than GEL-A, so pH control was needed in the application of this slow-release fertilizer.

Pollution Load Capacity Analysis of BOD, COD, and TSS in Karang Mumus River, Samarinda Vita Pramaningsih; Slamet Suprayogi; Ignasius Loyola Setyawan Purnama
Indonesian Journal of Chemistry Vol 20, No 3 (2020)
Publisher : Universitas Gadjah Mada

The Rivers in Indonesia often accommodate pollution from all community activities. This happened due to a large number of people who use watersheds for living. One of those rivers is the Karang Mumus River in Samarinda City, East Kalimantan. This study aims to analyze the capacity of the Karang Mumus River pollution load in segments 2, 3 and 4. The analysis model used in this study was the QUAL2Kw and ArcGIS models. The former used to calculate the capacity of river pollution and the latter used to determine land use. The results of the QUAL2Kw Model analysis shown that the capacity of the BOD was exceeded in all segments, COD was exceeded in all segments except segment 3. The entire segment had an allocation of sectoral pollution load originated from domestic activities. This study concluded that the dominant land use of settlements was one of the main causes of this problem.

Evaluation of Total Flavonoid, Total Phenolic Contents, and Antioxidant Activity of Strychnobiflavone Sana Ullah; Chang-Gu Hyun
Indonesian Journal of Chemistry Vol 20, No 3 (2020)
Publisher : Universitas Gadjah Mada

This work evaluates the antioxidant activity of strychnobiflavone due to the increasing demand of the antioxidant agents day by day. Various in vitro antioxidants assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were used to investigate the antioxidant activity of strychnobiflavone. The results of both DPPH and ABTS show that strychnobiflavone increase the scavenging activity in a concentration-dependent manner due to the phenolic and flavonoid contents. This study revealed that strychnobiflavone is one of the promising and an effective compound for the antioxidant agent.

Antibacterial Activity of Silver Nanoparticles Capped by p-Aminobenzoic Acid on Escherichia coli and Staphylococcus aureus Dian Susanthy; Sri Juari Santosa; Eko Sri Kunarti
Indonesian Journal of Chemistry Vol 20, No 1 (2020)
Publisher : Universitas Gadjah Mada

This paper describes the antibacterial performance of silver nanoparticles (AgNPs) which have been synthesized by using p-aminobenzoic acid as reducing and stabilizing agent simultaneously. The silver nitrate with various concentrations was reacted with pH 11-adjusted p-aminobenzoic acid with a concentration of 5 × 10–3 mol L–1 for 30 min in a boiling water bath. The synthesized AgNPs were characterized by UV-Vis spectrophotometry, Transmission Electron Microscope (TEM), and Particle Size Analyzer (PSA). The antibacterial performance of the synthesized AgNPs was evaluated by agar well diffusion method on Escherichia coli and Staphylococcus aureus. The higher silver nitrate concentration, the bigger the nanoparticle size, the wider particle size distribution, and the higher number of AgNPs formed. AgNPs synthesized from higher silver nitrate concentration had higher antibacterial activity. It is an indication that the antibacterial activity of AgNPs is mainly controlled by the silver ion concentration which influences the AgNPs particle size and existence of silver ion in the AgNPs colloidal solution

Antibacterial and Antioxidant Activities of Polyeugenol with High Molecular Weight Erwin Abdul Rahim; Nur Istiqomah; Gilang Almilda; Ahmad Ridhay; Ni Ketut Sumarni; Indriani Indriani
Indonesian Journal of Chemistry Vol 20, No 3 (2020)
Publisher : Universitas Gadjah Mada

This study was aimed to prepare polyeugenol with high molecular weight and to evaluate its antibacterial and antioxidant activities. First, polyeugenol was synthesized from eugenol in the presence of H2SO4-CH3COOH (4:1) as catalyst. The synthesized polyeugenol was weighed by using viscometer, revealing its high molecular weight of (7.76–21.9) × 105 g/mol. Furthermore, the antibacterial activity of the polyeugenol was conducted against Staphylococcus aureus and Escherichia coli bacteria. It was conducted by applying well diffusion method at 1, 2, 3, 4 and 5% concentrations to observe inhibition zones, in which the tests showed that the antibacterial activity of the polyeugenol against S. aureus were 17.42, 17.76, 18.79, 21.42 and 22.55 mm, while those against E. coli were 15.87, 17.23, 17.56, 18.24 and 19.21 mm, respectively. In short, these results indicated a strong antibacterial activity. Then, tests on antioxidant activity against free radical DPPH (2,2-diphenyl-1-pycrylhydrazyl) gave the IC50 value of 80.47 µg/mL, indicating a strong antioxidant activity. Therefore, the polymer synthesized in this work has a high potential to be applied in various biomedical applications.

Preparation of Ammonia Dealuminated Metakaolinite and Its Adsorption against Bixin Winda Rahmalia; Jean-Francois Fabre; Thamrin Usman; Zéphirin Mouloungui
Indonesian Journal of Chemistry Vol 20, No 4 (2020)
Publisher : Universitas Gadjah Mada

This study aims to prepare dealuminated metakaolinite which has a high surface area by using NH4OH as an activator. The natural kaolinite sample was treated at 600 °C for 6 h in order to obtain metakaolinite. A dealuminated metakaolinite was then prepared by the repeated activation method using concentrated ammonia (5 M NH4OH) at room temperature. Depending on the nature of each type of material, natural kaolinite, NH4OH treated kaolinite, metakaolinite and NH4OH treated metakaolinite were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET-N2) measurements. XRD and FTIR results confirmed that structural transformation from kaolinite to metakaolinite had occurred. According to SEM-EDS data, the activation of metakaolinite by NH4OH allowed the dealumination of metakaolinite. The increase in the Si/Al ratio was almost twice as high as in kaolinite. BET-N2 analysis showed that the specific surface area and the total pore volume increased significantly after activation. Its adsorption properties were tested against bixin. Bixin adsorption on dealuminated metakaolinite followed pseudo-second order kinetic where k2 = 0.20 g/mg min. The adsorption isotherm followed the Langmuir model where qm = 0.72 mg/g.

Electrical and Thermal Conductivity of Cyclic Natural Rubber/Graphene Nanocomposite Prepared by Solution Mixing Technique Vivi Purwandari; Saharman Gea; Basuki Wirjosentono; Agus Haryono; I Putu Mahendra; Yasir Arafat Hutapea
Indonesian Journal of Chemistry Vol 20, No 4 (2020)
Publisher : Universitas Gadjah Mada

Thermal and electrical conductivity studies of Cyclic Natural Rubber nanocomposite with graphene 1 and 2 phr (G1 and G2) and modified 1 and 2 graphenes (mG1 and mG2) have been carried out. Graphene was activated with cetrimonium bromide (CTAB), was isolated from Sawahlunto coal (Bb) by the Hummer modification method. The nanocomposite was fabricated through the mixing solution method using Xylena as a solvent. The characterizations of nanocomposites which were performed by Fourier Transform Infrared (FT-IR) and X-Ray Diffraction (XRD) reveals an interaction between graphene, CTAB and the CNR matrix. Furthermore, Scanning Electron Magnetic (SEM) and Transmission Electron Microscopy (TEM) indicate the particle size to be smaller and particle distribution is more in accordance with CTAB. Thermal analysis of nanocomposites using Differential Scanning Calorimeter (DSC) showed an increase in thermal conductivity from 3.0084 W/mK to 3.5569 W/mK. Analysis of electrical conductivity using the Two-Point Probe shows 2 phr mG (mG2) capable of increasing electrical conductivity from 0.1170 × 10–4 S/cm to 0.2994 × 10-4 S/cm.

The Effect of Bioactive Polyphenols from Anacardium occidentale Linn. Leaves on α-Amylase and Dipeptidyl Peptidase IV Activities Nur Imanina Abdullah Thaidi; Hanapi Mat Jusoh; Ahmad Badruddin Ghazali; Deny Susanti; Normah Haron
Indonesian Journal of Chemistry Vol 20, No 5 (2020)
Publisher : Universitas Gadjah Mada

Anacardium occidentale Linn. (A. occidentale L.) leaves possess bioactive polyphenols which are associated with antidiabetic potency for the management of type 2 diabetes mellitus (T2DM). In this study, free, soluble ester, and insoluble-bound phenolic fractions from young and mature leaves of A. occidentale L. were extracted. Subsequently, all fractions were investigated for their inhibitory effect on α-amylase and dipeptidyl peptidase IV (DPPIV) activities. Both free (72.45 ± 3.6%) and soluble ester (83.40 ± 4.7%) phenolic fractions in the mature leaves extracts had significantly demonstrated greater α-amylase inhibitors than the young leaves. Likewise, soluble ester (4.09 ± 0.34 µg/mL) and insoluble-bound (4.87 ± 0.32 µg/mL) phenolic fractions in the mature leaves extracts were significantly more effective in inhibiting DPPIV than the young leaves. As for fractions comparison, insoluble-bound derived from the young leaves extract was a more potent α-amylase inhibitor than free and soluble ester phenolic fractions (p < 0.0001). Besides, soluble ester and insoluble-bound phenolic fractions showed a stronger inhibitor of DPPIV than the free phenolic (p < 0.001), irrespective of the maturity of the leaves. In conclusion, this study showed that A. occidentale L. extracts possessed antidiabetic properties, which may potentially be used as an alternative treatment for T2DM management.

The Performance of a Fixed-Bed Anaerobic Bioreactor Using Sulfate-Reducing Bacterial Consortium from Sikidang Crater Sediments Andriyanto Andriyanto; Wahyu Wilopo; Endah Retnaningrum
Indonesian Journal of Chemistry Vol 20, No 1 (2020)
Publisher : Universitas Gadjah Mada

This research explored the performance of a fixed-bed anaerobic bioreactor system (FBR) using sulfate-reducing bacteria (SRB) from the sediment of Sikidang Crater in Indonesia. Indonesian natural zeolite was used as an inert medium in this bioreactor system. This bioreactor performance was analyzed based on its sulfate reduction efficiency, Cu removal, pH profile, SRB growth, and the changes in mineral composition of the zeolite surface. Based on a batch experiment, the FBR system was operated at 30 °C with a hydraulic retention time (HRT) of 7 days using a zeolite dose of 100 g/L. After its operation, a large amount of SRB (up to 1.5 × 105 cells/mm2) was entrapped and present in the zeolite. This bacterial consortium could reduce sulfate and copper by around 68% and 99.96%, respectively. In addition, the pH value of the bioreactor changed to neutral, which indicated a good performance of the operation. The result of the Energy-Dispersive X-ray (EDX) confirmed that copper removal was caused by the formation of copper-sulfide precipitation. Mapping also revealed that both copper and sulfur were precipitated at the same location.

Ionic Conductivity of Chitosan-Lithium Electrolyte in Biodegradable Battery Cell Ali Benouar; Mohammed Reda Ahmed Bacha
Indonesian Journal of Chemistry Vol 20, No 3 (2020)
Publisher : Universitas Gadjah Mada

The electrical conductivities of salts (LiCl, LiOH) in chitosan as an electrolyte in biodegradable batteries have been measured at the concentration range 10–100 mol m–3 in the temperature range 278–308 K. The data were interpreted in terms of ion–ion and ion–solvent interactions using the Fuoss paired ion. The fitting of Fuoss’ equation of 1978 to these data led us to an estimate of the ionic association by computing the conductimetric pairing constants. In order to optimize the use of the electrolyte in the clean lithium battery, the temperature dependency of conductivity will be studied using Arrhenius empirical equation. This equation was applied successfully in the temperature range used in this study.

Page 118 of 196 | Total Record : 1956

116 117 118 119 120

Filter by Year

2001 2025

Filter By Issues

All Issue Vol 25, No 5 (2025) Vol 25, No 4 (2025) Vol 25, No 3 (2025) Vol 25, No 2 (2025) Vol 25, No 1 (2025) Vol 24, No 6 (2024) Vol 24, No 5 (2024) Vol 24, No 4 (2024) Vol 24, No 3 (2024) Vol 24, No 2 (2024) Vol 24, No 1 (2024) Vol 23, No 6 (2023) Vol 23, No 5 (2023) Vol 23, No 4 (2023) Vol 23, No 3 (2023) Vol 23, No 2 (2023) Vol 23, No 1 (2023) Vol 22, No 6 (2022) Vol 22, No 5 (2022) Vol 22, No 4 (2022) Vol 22, No 3 (2022) Vol 22, No 1 (2022) Vol 22, No 2 (2022) Vol 21, No 6 (2021) Vol 21, No 5 (2021) Vol 21, No 4 (2021) Vol 21, No 3 (2021) Vol 21, No 2 (2021) Vol 21, No 1 (2021) Vol 20, No 6 (2020) Vol 20, No 5 (2020) Vol 20, No 4 (2020) Vol 20, No 3 (2020) Vol 20, No 2 (2020) Vol 20, No 1 (2020) Vol 19, No 4 (2019) Vol 19, No 3 (2019) Vol 19, No 2 (2019) Vol 19, No 1 (2019) Vol 18, No 4 (2018) Vol 18, No 3 (2018) Vol 18, No 2 (2018) Vol 18, No 1 (2018) Vol 17, No 3 (2017) Vol 17, No 2 (2017) Vol 17, No 1 (2017) Vol 16, No 3 (2016) Vol 16, No 2 (2016) Vol 16, No 1 (2016) Vol 15, No 3 (2015) Vol 15, No 2 (2015) Vol 15, No 1 (2015) Vol 14, No 3 (2014) Vol 14, No 2 (2014) Vol 14, No 1 (2014) Vol 13, No 3 (2013) Vol 13, No 2 (2013) Vol 13, No 1 (2013) Vol 12, No 3 (2012) Vol 12, No 2 (2012) Vol 12, No 1 (2012) Vol 11, No 3 (2011) Vol 11, No 2 (2011) Vol 11, No 1 (2011) Vol 10, No 3 (2010) Vol 10, No 2 (2010) Vol 10, No 1 (2010) Vol 9, No 3 (2009) Vol 9, No 2 (2009) Vol 9, No 1 (2009) Vol 8, No 3 (2008) Vol 8, No 2 (2008) Vol 8, No 1 (2008) Vol 7, No 3 (2007) Vol 7, No 2 (2007) Vol 7, No 1 (2007) Vol 6, No 3 (2006) Vol 6, No 2 (2006) Vol 6, No 1 (2006) Vol 5, No 3 (2005) Vol 5, No 2 (2005) Vol 5, No 1 (2005) Vol 4, No 3 (2004) Vol 4, No 2 (2004) Vol 4, No 1 (2004) Vol 3, No 3 (2003) Vol 3, No 2 (2003) Vol 3, No 1 (2003) Vol 2, No 3 (2002) Vol 2, No 2 (2002) Vol 2, No 1 (2002) Vol 1, No 3 (2001) Vol 1, No 2 (2001) Vol 1, No 1 (2001) Article in press ARTICLE IN PRESS More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kab. sleman, Daerah istimewa yogyakarta INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA