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Publisher: Universitas Gadjah Mada   (Total: 39 journals)   [Sort by number of followers]

Showing 1 - 39 of 39 Journals sorted alphabetically
Agritech     Open Access   (Followers: 1)
Berkala Ilmu Perpustakaan dan Informasi     Open Access   (Followers: 1)
Buletin Peternakan : Bulletin of Animal Science     Open Access   (Followers: 1)
Buletin Psikologi     Open Access  
Gadjah Mada Intl. J. of Business     Open Access   (SJR: 0.127, CiteScore: 0)
IJEIS (Indonesian J. of Electronics and Instrumentation Systems)     Open Access   (Followers: 3)
Indonesian J. of Biotechnology     Open Access   (Followers: 1)
Indonesian J. of Chemistry     Open Access   (Followers: 1, SJR: 0.209, CiteScore: 1)
Indonesian J. of Community Engagement     Open Access  
Indonesian J. of Computing and Cybernetics Systems     Open Access   (Followers: 1)
Indonesian J. of Geography     Open Access   (Followers: 2, SJR: 0.217, CiteScore: 1)
Indonesian J. of Pharmacy     Open Access  
J. of Applied Geology     Open Access   (Followers: 1)
J. of Fisheries Sciences     Open Access   (Followers: 1)
J. of Food and Pharmaceutical Sciences     Open Access   (Followers: 1)
J. of Indonesian Economy and Business     Open Access   (Followers: 2)
J. of the Civil Engineering Forum     Open Access  
J. of the Medical Sciences (Berkala ilmu Kedokteran)     Open Access   (Followers: 1)
JKAP (Jurnal Kebijakan dan Administrasi Publik)     Open Access  
Jurnal Filsafat     Open Access  
Jurnal Gizi Klinik Indonesia     Open Access  
Jurnal Humaniora     Open Access   (Followers: 1)
Jurnal Ilmu Kehutanan     Open Access   (Followers: 1)
Jurnal Kajian Seni     Open Access  
Jurnal Kawistara     Open Access  
Jurnal Ketahanan Nasional     Open Access  
Jurnal Manusia dan Lingkungan     Open Access   (Followers: 1)
Jurnal Mimbar Hukum Fakultas Hukum Universitas Gadjah Mada     Open Access  
Jurnal Nasional Teknik Elektro dan Teknologi Informasi     Open Access  
Jurnal Pariwisata Terapan     Open Access  
Jurnal Pengabdian Kepada Masyarakat (Indonesian J. of Community Engagement)     Open Access  
Jurnal Psikologi     Open Access  
Jurnal Sain Veteriner     Open Access  
Jurnal Teknosains     Open Access  
Majalah Geografi Indonesia     Open Access  
Majalah Kedokteran Gigi Indonesia     Open Access  
Poetika : Jurnal Ilmu Sastra     Open Access  
Populasi     Open Access  
Traditional Medicine J.     Open Access   (Followers: 1)
Journal Cover
Indonesian Journal of Chemistry
Journal Prestige (SJR): 0.209
Citation Impact (citeScore): 1
Number of Followers: 1  

  This is an Open Access Journal Open Access journal
ISSN (Print) 1411-9420 - ISSN (Online) 2460-1578
Published by Universitas Gadjah Mada Homepage  [39 journals]
  • Electrically Conductive Nanocomposites Polymer of Poly(Vinyl
           Alcohol)/Glutaraldehyde/Multiwalled Carbon Nanotubes: Preparation and
           Characterization

    • Authors: Fitri Khoerunnisa, Hendrawan Hendrawan, Yaya Sonjaya, Rizki Deli Hasanah
      Pages: 383 - 389
      Abstract: Electrically conductive nanocomposites polymer of poly(vinyl alcohol)/PVA, glutaraldehyde (GA) and multiwalled carbon nanotubes (MWCNT) has been successfully synthesized. The polymer nanocomposites were prepared by mixing PVA, GA (crosslinker), and MWCNT dispersion with an aid of ultrasonic homogenizer at 50 °C. The content of MWCNT, in particular, was varied in order to determine the effect of MWCNT on electrical conductivity of polymer composites. The polymer mixture was casted into a disc to obtain thin film. The electrical conductivity, surface morphology, and mechanical properties of the composites film were investigated by means of four probes method, FTIR spectroscopy, X-ray diffraction, SEM, AFM, and tensile strength measurement, respectively. It was found that the optimum composition of PVA (10%): GA (1%): MWCNT (1%) was 20:20:3 in volume ratio. The addition of MWCNT induced the electrically conductive network on polymer matrix where the electrical conductivity of nanocomposites film significantly increased up to 8.28 x 10-2 S/sq due to reduction of the contact resistance between conductive filler. Additionally, the mechanical strength of nanocomposites polymer were significantly increased as a result of MWCNT addition. Modification of morphological structure of composite film as indicated by FTIR spectra, X-ray diffraction patterns, SEM, and AFM images verified the effective MWCNT filler network in the polymer matrix.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.26620
      Issue No: Vol. 18, No. 3 (2018)
       
  • Synthesis and Characterization of Lignin-Based Polyurethane as a Potential
           Compatibilizer

    • Authors: Salma Ilmiati, Jana Hafiza, Jaka Fajar Fatriansyah, Elvi Kustiyah, Mochamad Chalid
      Pages: 390 - 396
      Abstract: Lignin is one of the most abundant biopolymer on earth. It has polar and non-polar side due to its hyperbranched structure, but the polarity of lignin has a higher tendency than non-polarity. Lignin has potential to be compatibilizer if the portion of non-polar can be increased. This research is focused on investigate the synthesis of lignin-based polyurethane to enhance the portion of non-polarity in lignin. Lignin-based polyurethane was prepared by reacting variation 4,4'-Methylenebis(cyclohexyl isocyanate) (HMDI) and polyethylene glycol (PEG), then lignin was added to the reaction. In this study, the structure of lignin-based polyurethane was confirmed by NMR and FTIR. NMR and FTIR showed that lignin successfully grafted. NMR, also used to investigate the variation molar mass of PEG and isocyanate contents effects to polarity of lignin-based polyurethane. The polarity of lignin-based polyurethane decrease as the composition of HMDI and molecular weight of PEG increase. This result also occurs on the sessile drop test that used to determine surface tension of lignin-based polyurethane. The thermal properties of lignin-based polyurethane also investigate using STA. Based on STA, enhancement of composition of HMDI and PEG increase thermal degradation and resistance of lignin-based polyurethane.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.27176
      Issue No: Vol. 18, No. 3 (2018)
       
  • The Effect of Alkaline Activator Types on Strength and Microstructural
           Properties of Geopolymer from Co-Combustion Residuals of Bamboo and Kaolin
           

    • Authors: Aprilina Purbasari, Tjokorde Walmiki Samadhi, Yazid Bindar
      Pages: 397 - 402
      Abstract: Geopolymer as a Portland cement substitute had been synthesized from alkaline activation of co-combustion residuals of bamboo and kaolin. Types of used alkaline activators were NaOH solution, KOH solution, a mixture of NaOH solution-water glass, and a mixture of KOH solution-water glass. Geopolymer with NaOH solution as activator had a compressive strength which was higher compared to geopolymer with KOH solution as an activator. However, geopolymer with NaOH solution-water glass as activator had a compressive strength which was lower compared to geopolymer with KOH solution-water glass as activator either at room temperature curing or at a curing temperature of 60 °C. The use of water glass with NaOH or KOH solution as activator could increase the compressive strength of geopolymer and yielded geopolymer having more dense and more homogeneous microstructure seen from SEM images. XRD patterns revealed the presence of sodium aluminosilicate hydrate in geopolymer with NaOH solution and NaOH solution-water glass as activators, and potassium aluminosilicate hydrate in geopolymer with KOH solution and KOH solution-water glass as activators. Furthermore, FTIR spectra indicated asymmetrical vibration of Si(Al)-O at around 1008 cm-1 related to geopolymer product.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.26534
      Issue No: Vol. 18, No. 3 (2018)
       
  • Synthesis and Photoactivity of Fe3O4/TiO2-Co as a Magnetically Separable
           Visible Light Responsive Photocatalyst

    • Authors: Eko Sri Kunarti, Indriana Kartini, Akhmad Syoufian, Karolina Martha Widyandari
      Pages: 403 - 410
      Abstract: Synthesis of magnetic photocatalyst, Fe3O4/TiO2-Co, with characterization and photoactivity examination have been conducted. The synthesis was initiated by preparation of Fe3O4 particles using coprecipitation method. The Fe3O4 particles were then coated with TiO2-Co at a various ratio of Fe3O4:TiO2 and concentration of Co(II) dopant. The Fe3O4/TiO2-Co was characterized by FTIR, XRD, TEM, SEM-EDX, VSM, and SR UV-visible methods. Photoactivity of the Fe3O4/TiO2-Co was carried out using methylene blue as a target molecule in degradation reaction within a batch system. By using optimum conditions, the degradation of methylene blue solution was performed under exposure to UV, visible light and dark condition. Results showed that the Fe3O4/TiO2-Co formation was confirmed by the presence of Fe3O4 and anatase diffraction peaks in the X-ray diffractogram. SR UV-Vis spectra indicated that the Fe3O4/TiO2-Co was responsive to visible light. Band gap energy of the Fe3O4/TiO2-Co with dopant concentration of 1; 5; 10 and 15% were 3.22; 3.12; 3.09 and 2.81 eV, respectively. The methylene blue solution can be well photodegraded at a pH of 10 for 210 min. The Fe3O4/TiO2-Co has the highest ability to methylene blue photodegradation with dopant concentration of 10% gave degradation yield of 80.51 and 95.38% under UV and visible irradiation, respectively.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.26831
      Issue No: Vol. 18, No. 3 (2018)
       
  • Preparation of Graphene-Polyaniline-Cellulose Double Network Hydrogels
           

    • Authors: Deni Swantomo, Kris Tri Basuki, Sigit Sigit, Yadi Yunus
      Pages: 411 - 420
      Abstract: In order to achieve high performance of electrochemical properties, numerous efforts have been devoted to the development of advanced multi-component hybrid double network hydrogel materials. In this research, the double network hydrogels were synthesized using one pot method by graft copolymerization of aniline onto graphene and cellulose using gamma irradiation as initiator. The formation of the double network hydrogels was confirmed by the Fourier Transform Infrared Spectroscopy (FTIR) study. X-ray Diffraction (XRD) analysis showed that the crystalline was increased through graft copolymerization graphene-aniline-cellulose double network. It was found that the crosslink density increased with increasing aniline volume and increasing radiation doses inversely with the swelling degree. Electrochemical measurements exhibited that increasing aniline volume and radiation doses increased specific capacitance and conductivity of the hydrogels. When compared with the pure graphene, the synthesized double network hydrogels exhibits remarkably enhanced specific capacitance of 9.774 F g-1 and conductivity i.e. 4.766 x 10-2 Scm-1 in 0.5 M HCl solution at aniline volume 8 mL and radiation dose 80 kGy. The improved electrochemical properties of the double network hydrogels represented an alternative promising candidate for the application as energy storage devices and offered a new facile method.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.30467
      Issue No: Vol. 18, No. 3 (2018)
       
  • The Synthesis and Stability Study of Silver Nanoparticles Prepared by
           Using p-Aminobenzoic Acid as Reducing and Stabilizing Agent

    • Authors: Dian Susanthy, Sri Juari Santosa, Eko Sri Kunarti
      Pages: 421 - 427
      Abstract: A study to examine the performance of p-aminobenzoic acid as both reducing agent for silver nitrate to silver nanoparticles (AgNPs) and stabilizing agent for the formed AgNPs has been done. The synthesis of AgNPs was performed by mixing silver nitrate solution as precursor with p-aminobenzoic acid solution and heating it in a boiling water bath. After the solution turned to yellow, the reaction stopped by cooling it in tap water. The formed AgNPs were analyzed by using UV-Vis spectrophotometry to evaluate their SPR absorption in wavelength range of 400–500 nm. The synthesis process was highly depend on the pH, reaction time, and mole ratios of the reactants. The synthesis only occur in pH 11 and at reaction time 30 min, the particle size of the formed AgNPs was 12 ± 7 nm. Longer reaction time increased the reducing performance of p-aminobenzoic acid in AgNPs synthesis but decreased its stabilizing performance. The increase of silver nitrate amount relative to p-aminobenzoic acid in the synthesis increased the reducing and stabilizing performance of p-aminobenzoic acid and the optimum mole ratio between AgNO3 and p-aminobenzoic acid was 5:100 (AgNO3 to p-aminobenzoic acid).
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.29312
      Issue No: Vol. 18, No. 3 (2018)
       
  • Modified Silica Adsorbent from Volcanic Ash for Cr(VI) Anionic Removal

    • Authors: Endang Tri Wahyuni, Roto Roto, Firda Ainun Nissa, Mudasir Mudasir, Nurul Hidayat Aprilita
      Pages: 428 - 433
      Abstract: In the present research, cetyltrymethyl ammonium bromide (CTAB)-modified silica from Kelud’s volcanic ash has been prepared and examined as adsorbent for removal of the hazardous Cr(VI) anion. The research was initiated with purification of SiO2 from the volcanic ash that was carried out by reacting the volcanic ash with NaOH powder at 900 °C for 2 h, followed by dissolving the ash to water at 100 °C, and then was acidified with HCl 1 M to form hydrogel. By calcination of the hydrogel, silica (SiO2) gel was obtained. The next step was modification of the silica with CTAB, that was performed by interacting the CTAB solution with the gel, in which the concentration of the CTAB was varied. Then the CTAB-modified silica samples were characterized by using FTIR, XRD, and SEM machines. The activity of the adsorbent was examined for adsorption of CrO4= in the solution. The results of the research demonstrate that the amorphous silica gel and the amorphous CTAB-modified silica have been obtained. The CTAB-modified silica was found to possess much higher ability in the adsorption of CrO4= anion, that was 48.90 mg/g, compared to that of the unmodified silica gel, as much 5.68 mg/g. These findings strongly prove that the negative surface of the CTAB-modified silica adsorbent has been successfully formed. Furthermore, it is also observed that increasing concentration of CTAB in SiO2-CTA can promote more effective adsorption of the CrO4= from the solution, but the further enlargement of the CTAB concentration leads to the adsorption decreased, and the highest adsorption was shown by CTAB-modified silica prepared with 0.10 mole of CTAB/1 mole SiO2.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.26905
      Issue No: Vol. 18, No. 3 (2018)
       
  • Synthesis of Citrate-Capped Gold Nanoparticles from Reduced [AuCl4]– on
           Ascorbic Acid-Immobilized Mg/Al Hydrotalcite

    • Authors: Agustina Sus Andreani, Suyanta Suyanta, Eko Sri Kunarti, Sri Juari Santosa
      Pages: 434 - 440
      Abstract: Reductive adsorption of [AuCl4]-– by using ascorbic acid immobilized on Mg/Al hydrotalcite (Mg/Al HT) and synthesis of gold nanoparticles (AuNPs) from the reduced gold using sodium citrate have been conducted. Mg/Al HT was synthesized by co-precipitation method at pH 10 with molar ratio of Mg(II) and Al(III) 2:1. Ascorbic acid (AA) was then immobilized on Mg/Al HT to form hybrid of AA and Mg/Al HT (Mg/Al HT-AA). Mg/Al HT-AA was used to reductively adsorb [AuCl4]– and the formed Au(0) was extracted by using sodium citrate to form citrate-capped AuNPs. The formation of AuNPs from 100 mg/L [AuCl4]– solution removed by 60 mg Mg/Al HT-AA was optimum at pH 5.0, by using 70 mM sodium citrate and 2 h sonication time. This optimum condition was successfully applied to synthesize AuNPs from [AuCl4]– as the leaching product of gold from PCB using aquaregia.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.30203
      Issue No: Vol. 18, No. 3 (2018)
       
  • Synthesis of Ce-Mesoporous Silica Catalyst and Its Lifetime Determination
           for the Hydrocracking of Waste Lubricant

    • Authors: Wega Trisunaryanti, Triyono Triyono, Iip Izul Falah, Andreas David Siagian, Muhammad Fajar Marsuki
      Pages: 441 - 447
      Abstract: The synthesis of Ce/mesoporous silica (Ce/MS) and its lifetime determination for the hydrocracking of waste lubricant has been carried out. The MS was synthesized using tetraethyl orthosilicate (TEOS) and gelatin extracted from bovine bone as a template. Cerium was impregnated onto the MS by wet impregnation method using Ce(NO3)3.6H2O. The MS and Ce/MS were then characterized by means of acidity using ammonia base vapor adsorption, Fourier Transform Spectrophotometer (FTIR), Transmission Electron Microscope (TEM), Scanning Electron Microscope-Energy Dispersive X-ray Spectrometer (SEM-EDX), and surface area analyzer (SAA) based on the BET and BJH equation. The Ce/MS catalyst was tested in hydrocracking of waste lubricant in three runs. Lifetime of Ce/MS catalyst was determined using a linear regression of the liquid product yields vs hydrocracking time. The Ce/MS catalyst showed an acidity of 2.79 mmol/g, BJH desorption pore diameter of 3.84 nm, BET surface area of 246.55 m2/g, and total pore volume of 0.44 cm3/g. The yield of liquid product obtained from hydrocracking of waste lubricant using the Ce/MS catalyst for the first, second, and third runs was 21.42, 17.23 and 10.54 wt.%, respectively for 2.5 h per each run. Lifetime of Ce/MS catalyst in hydrocracking of waste lubricant was 12.54 h.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.31717
      Issue No: Vol. 18, No. 3 (2018)
       
  • Analysis Methods for Development of Standard Reference Material (SRM)
           Zircon Minerals Synthesis

    • Authors: Samin Samin, Susanna Tuning Sunanti
      Pages: 448 - 456
      Abstract: The synthesis method of in-house zircon minerals certified reference material (CRM) from Kalimantan (Tumbang Titi), and Bangka has been studied with statistical method of ISO 13528-2008 and ISO 35-2006. Zircon Minerals weighing of 10 kg, and it was dried at 90 °C for 2 × 6 h in a closed room, then crushed with a Ball-Mill up to passes 200 mesh, and homogenized in a homogenizer for 3 × 6 h. The water content in zircon minerals powder is tested by gravimetric method, whereas the homogeneity and stability assessed by statistical methods. Zircon mineral powders are distributed to seven accredited testing laboratory for testing the composition and content of the oxides with the validated analytical methods. Standardization and characterization of candidate zircon mineral certified reference materials are done by using XRD (X-Ray Diffraction) and used standard materials of JCRM R 502 from Japan. The test results of oxide concentrations from various laboratories processed with statistical methods. From the data by test laboratories obtained 40 bottles of the prototype in-house certified reference materials zircon mineral powders from Kalimantan and Bangka with a capacity of 100 g. Based on standardization and characterization test data obtained a major chemical compound on zircon minerals Kalimantan and Bangka similar to the standard that is ZrSiO4. This in-house CRM is traced to certified reference materials from Japan (JCRM-502).
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.25194
      Issue No: Vol. 18, No. 3 (2018)
       
  • Characteristics of Trace Elements in Volcanic ash of Kelud Eruption in
           East Java, Indonesia

    • Authors: Diah Dwiana Lestiani, Revi Apryani, Linda Lestari, Muhayatun Santoso, Eko Prabowo Hadisantoso, Syukria Kurniawati
      Pages: 457 - 463
      Abstract: The eruption of Mount Kelud that occurred on February 13, 2014, ejected a huge plume of ash and sand exceeding 26 km into the air which moved west over the island. The elements content in volcanic ash is important information for further study such as the possibility to utilize the ash. In this study, the volcanic ashes collected from four affected areas in Java were analyzed using neutron activation analysis (NAA) with HPGe detector and X-ray fluorescence. Method validation was applied using the standard reference material SRM NIST 2711a Montana Soil with recovery and accuracy in a good agreement for all elements. The analysis results of volcanic ashes showed a wide range of elements, major elements Al, Ca, Fe, K, Mg, Mn, Na, Si and Ti, trace elements As, Cd, Cu, Co, Cr, V, Zn, Hf, Th and U, and rare earth elements were identified. The results showed heavy metals As, Cd, Cu, Co, Cr, and Pb were ranged 3.23–4.42, 17.63–24.09, 49.26–77.10, 10.86–16.03, 11.19–17.79 and 31.4–42.7 mg/kg, respectively, while rare earth elements such as Ce, Eu, La, and Sm were 9.84–18.43, 0.73–1.02, 2.25–5.66 and 1.34–2.63 mg/kg respectively. Comparison with other volcanic ashes from Indonesia such as Merapi and Sinabung and world volcanic ashes were applied. The results of the characteristic of elements in Kelud volcanic ash would be valuable information as reference data for their potential utilization.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.26876
      Issue No: Vol. 18, No. 3 (2018)
       
  • Integrative Assessment of Pb and Cd Pollution in Porong Estuaries Using
           Sediment Chemistry, Bioavailability, and Bioconcentration Factor

    • Authors: Barlah Rumhayati, Catur Retnaningdyah
      Pages: 464 - 471
      Abstract: The aims of the research were to perform an integrative assessment of high metal pollution in Porong Estuary by determining (i) the distribution of heavy metals fraction in sediment, (ii) the potential risk of sediment to the metal bioavailability, and (iii) the bioaccumulation factor of heavy metals in benthic. Fractionation of heavy metals in the sediments was carried out by the European Community Bureau of Reference (BCR) sequential extraction method. The potential risk of sediment was determined from RAC (risk assessment code) value. Bioconcentration factor was determined based on the ratio of the concentration of heavy metals in benthic to the concentration of bioavailable metals from sediments. Heavy metal concentrations were measured using AAS. The results showed that non-resistant Pb and Cd was higher than resistant fractions. As a non-resistant fraction, Pb was found mostly as fraction 2, i.e., metal fraction adsorbed on the surface of the iron oxy/hydroxide sediment (34.5 ± 4.9%). Cd was more prevalent as fraction 3, i.e., an organic bound fraction (29.0 ± 1.8%). Furthermore, Porong Estuary sediments had medium risk for contributing the bioavailable Cd in the water bodies based on the RAC (15.6 ± 1.8%). Based on the bioconcentration factor, accumulation of Cd and Pb was low (48.00 ± 7.62% for BCF-Cd and 32.29 ± 6.90% for BCF-Pb). Based on the results above, it could be concluded that the Porong Estuary water bodies have not been polluted by Pb and Cd released from the aquatic sediment.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.26603
      Issue No: Vol. 18, No. 3 (2018)
       
  • Heavy Metal Removal from Aqueous Solution Using Biosurfactants Produced by
           Pseudomonas aeruginosa with Corn Oil as Substrate

    • Authors: Venty Suryanti, Sri Hastuti, Tutik Dwi Wahyuningsih, Mudasir Mudasir, Dian Kresnadipayana, Inge Wiratna
      Pages: 472 - 478
      Abstract: The batch removal of Cu(II), Cd(II) and Pb(II) from individual heavy metal ion aqueous synthetic solution using biosurfactants produced by Pseudomonas aeruginosa with corn oil as substrate was investigated. The metal ion removal process of crude preparation biosurfactants (CPB) was established to be dependent on the initial pH and contact time. The optimum metal removal was observed at pH 6.0 of the initial metal solution and 10 min of contact time. The affinity sequence for metal ion removal was Pb(II)>Cd(II)>Cu(II). The removal capacity value of biosurfactant for Cu(II), Cd(II) and Pb(II) from single metal ions solution were 0.169, 0.276 and 0.323 mg/g, respectively. The removal capacity value of biosurfactant for Cu(II), Cd(II) and Pb(II) from multi metal ions solution were 0.064, 0.215 and 0.275 mg/g, respectively. The removal capacity of individual metal ion was diminished by the presence of other metal ions in multi metal ions from synthetic aqueous solution. The removal capacity value of biosurfactant for Cu(II), Cd(II) and Pb(II) from silver industry wastewater were 0.027, 0.055 and 0.291 mg/g, respectively. The results indicated that biosurfactants have potential to be used in the remediation of heavy metals in industrial wastewater.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.28805
      Issue No: Vol. 18, No. 3 (2018)
       
  • Ag/AgCl Reference Electrode Based on Thin Film of Arabic Gum Membrane

    • Authors: Sagir Alva, Aiman Sajidah binti Abdul Aziz, Mohd Ismahadi bin Syono, Wan Adil bin Wan Jamil
      Pages: 479 - 485
      Abstract: The Ag/AgCl reference electrode based on the Arabic Gum (AG) hydrogel films was successfully developed. The Arabic Gum concentration used in this study was 10–40% (w/v) with an optimum concentration of 20% (w/v). In this study, reference electrode performance testing is based on DmV response of Cl-ion’s measurements, stability tests and performance testing against ISE sensors such as K+, NH4+, and NO3-. The Ag/AgCl based reference electrode of the Arabic Gum film shows an average DmV of 4.0 ± 0.7 mV when response test is performed against a standard Ag/AgCl double junction electrode in various concentrations of Cl-ion’s. Meanwhile, in stability testing conducted in a 0.01 M KCl solution for 72 h found drift of < 0.6 mV/h. The reference performance test of the Arabic Gum reference electrode with three types of ISE NH4+, K+ and NO3- commercial sensors obtaining a slope closer to the Nernst value is 54.9 ± 0.9, 52.3 ± 0.5 and -53.2 ± 0.2 mV/dec with all having a linear distance of 0.1–10-5 M.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.28859
      Issue No: Vol. 18, No. 3 (2018)
       
  • Qualitative and Quantitative Phase-Analysis of Undoped Titanium Dioxide
           and Chromium Doped Titanium Dioxide from Powder X-Ray Diffraction Data

    • Authors: Hari Sutrisno, Ariswan Ariswan, Dyah Purwaningsih
      Pages: 486 - 495
      Abstract: Undoped titanium dioxide (TiO2) and a series of chromium(III) doped TiO2 (Cr-doped TiOfig. 12) with various %wt Cr atom were prepared by a reflux technique. The undoped TiO2 and Cr-doped TiO2 of 1.1, 3.9, 4.4 %wt Cr atom have been successfully analyzed both qualitative and quantitative analysis of powder X-ray diffraction (XRD) data. The qualitative analysis was carried out with the identification of phases in all samples by comparison with Crystallography Open Database (COD) and International Centre for Diffraction Data (ICDD), while the quantitative phase analysis was calculated by reference intensity ratio (RIR) and whole-pattern fitting (Rietveld analysis) methods. The undoped TiO2 consist of three phases: anatase, rutile, and brookite. In the 1.1 %wt Cr-doped TiO2 are detected presenting two phases: anatase (major) and rutile (minor). In the 3.9 %wt Cr-doped TiO2 andin the 4.4 %wt Cr-doped TiO2 consist of anatase as major phase, while CrO2 and TiO2-II phases can be detected as minor phases. The undoped TiO2 was refined in the phase, crystal system and space group of anatase (tetragonal, I41/amd), rutile (tetragonal, P42/mnm) and brookite (orthorhombic, Pbca), while the 1.1 %wt Cr-doped TiO2 was refined based on anatase (tetragonal, I41/amd), rutile (tetragonal, P42/mnm). Finally, in the 3.9 %wt Cr-doped TiO2 and 4.4 %wt Cr-doped TiO2,respectively were refined in the crystal system and space group of anatase (tetragonal, I41/amd).
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.28892
      Issue No: Vol. 18, No. 3 (2018)
       
  • Analytical Method Validation and Determination of Free Drug Content of
           4-n-Butylresorcinol in Complex Lipid Nanoparticles Using RP-HPLC Method

    • Authors: Rini Dwiastuti, Marchaban Marchaban, Enade Perdana Istyastono, Florentinus Dika Octa Riswanto
      Pages: 496 - 502
      Abstract: Lipid nanoparticles, one of nanoparticle technology results has been developed both as a drug delivery system and as a research object. Complex lipid nanoparticle, in the drug delivery system development, has an advantage due to its less toxicity. It is important to develop a validated analytical method to determine the drug content in the system of nanoparticle lipid. This research aimed to develop a valid RP-HPLC method to determine free drug content of 4-n-butylresorcinol in the liposome matrix followed by the determination of the encapsulation efficiency (EE%). A system of the RP-HPLC method has been developed using a column of C18 and methanol-redistilled water-glacial acetic acid 79:20:1 (v/v) as the mobile phase with pH maintained at 2.1–2.6. This method was validated in the parameters of selectivity, sensitivity, linearity, accuracy, and precision. During 30 days of storage, the complex lipid nanoparticle system showed the increase in the EE% value during storage time.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.28919
      Issue No: Vol. 18, No. 3 (2018)
       
  • Accumulation and Translocation of Heavy Metals by Acalypha wilkesiana
           Parts in the Phytoextraction of Contaminated Soil

    • Authors: Naseer Inuwa Durumin Iya, Zaini Bin Assim, Isa Bin Ipor, Ajoke Omonrinoye Omolayo, Isaac John Umaru, Binta Hadi Jume
      Pages: 503 - 513
      Abstract: This study was to investigate survival, growth and accumulation potential of Acalypha wilkesiana in phytoextraction of heavy metals contaminated soil. Acalypha wilkesiana was tested to evaluate its tolerance and phytoextraction capacity in soils contaminated with metals. It was tested under 10 mL of 100 mg/kg of As, Cr, Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn solution, along 240 days in greenhouse experiment with harvesting period of 60 days interval. Twenty four cuttings from Acalypha wilkesiana were subjected to the same treatment. Plants roots stem and leaves were dry-digested and analyzed using Atomic Absorption Spectrophotometer (AAS). Results show that Fe was the most accumulated metal followed by Cu, Mn, As and Zn with 5002.4, 542.7, 492.2, 396.7 and 308.2 mg/kg, respectively. The concentration of Cr, Ni, and Co was 101.2, 99.09, and 89.63mg/kg respectively. The highest concentration of Pb was 46.44 mg/kg, Cd was not detected by the plant. Bioconcentration Factor (BCF) of metals were above unity in root, stem, and leaf except for Fe which showed a value below the unity, and Pb shows highest BF value of 7.79. The Translocation Factor (TF) of Cr, Co, Fe, Ni, and Pb were higher, while that of As, Cu, Mn, and Zn were below the unity, Co showed the highest value of 15.93. Furthermore, Extraction Coefficient (EC) of Cr, Co, Ni, and Pb were greater than 1, while for remaining metals were lower than unity, the highest EC was observed from Pb with a value 17.21.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.31726
      Issue No: Vol. 18, No. 3 (2018)
       
  • Isolation, Cellulase Activity Test and Molecular Identification of
           Selected Cellulolytic Bacteria Indigenous Rice Bran

    • Authors: Akyunul Jannah, Aulanni`am Aulanni`am, Tri Ardyati, Suharjono Suharjono
      Pages: 514 - 521
      Abstract: Rice bran is the waste product of rice milling which is abundant in Indonesia, it can be used as a raw material for the manufacture of bioethanol by fermentation. Before being fermented, rice bran must be hydrolyzed into glucose by biomass degrading. This study was aimed to isolate indigenous cellulolytic bacteria from rice bran as producer of cellulolytic enzymes and resulted in 22 bacterial isolates that demonstrated cellulolytic activity being identified. Among them, BE 8 and BE 14 isolates showed the highest endoglucanase activity at 2.16 and 1.31 U/mL respectively. Identification of the 16S rDNA showed that BE 8 belongs to Bacillus subtilis and BE 14 in Bacillus cereus.

      PubDate: 2018-08-30
      DOI: 10.22146/ijc.26783
      Issue No: Vol. 18, No. 3 (2018)
       
  • Optimization and Validation of an HPLC-UV Method for Determination of
           Benzoic Acid and Sorbic Acid in Yogurt and Dried-Yogurt Products Using a
           Design of Experiment

    • Authors: Ala Yahya Sirhan
      Pages: 522 - 530
      Abstract: A method for the determination and analysis of benzoic acid and sorbic acid in yogurt and dried-yogurt products has been developed. This method was based on the use of a simple solid-liquid extraction method, followed by the high-performance liquid chromatography with a UV detector (HPLC–UV), enhanced with the aid of response surface methodology and design of experiment (DOE). The method excludes the use of complicated procedures, time-consuming and labor-intensive pre-treatment processes. Separation of the benzoic acid and sorbic acid with higher selectivity and sensitivity, and within reasonable retention time was performed by using an isocratic mobile phase of acetate buffer (pH 5.6)-methanol 60:40 at a column temperature of 25 °C. Optimization of sample preparation and analytical conditions gave recoveries in the range of 81 to 111% at spike levels of 2–20 mg/L and the relative standard deviations (RSDs) was lower than 9% in all cases. The intra-day precision and inter-day precision results were in the range of 8.4–8.5% and 10.4–11.0%. Additionally, the limits of detection (LOD) were 0.66 and 0.51 mg/L and the limits of quantification (LOQ) were 1.3 and 1.0 mg/L for benzoic acid and sorbic acid, respectively.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.27675
      Issue No: Vol. 18, No. 3 (2018)
       
  • Improvement in vitro Dissolution Rate of Quercetin Using Cocrystallization
           of Quercetin-Malonic Acid

    • Authors: Dwi Setyawan, Sukma Adhi Permata, Ahmad Zainul, Maria Lucia Ardhani Dwi Lestari
      Pages: 531 - 536
      Abstract: The aim of the study was to improve the in-vitro dissolution rate of quercetin (Qu) using cocrystallization of quercetin. Cocrystals of quercetin (Co Qu) were produced with malonic acid (Ma) as coformer at ratio 1:2 using solvent evaporation method. Cocrystals quercetin-malonic acid (Co Qu-Ma) was characterized using Differential Thermal Analysis (DTA), Powder X-Ray Diffraction (PXRD), Scanning Electron Microscope (SEM), and Fourier Transforms Infrared Spectrophotometer (FTIR) and in-vitro dissolution study. A new endothermic peak at 277.9 °C was shown from the thermogram. Diffractogram of Co Qu-Ma showed a new diffraction peak at 2θ 9.81, 12.99, and 19.80°. Microphotograph showed that Qu and Ma exhibited a columnar-shaped and a pebble-shaped crystal, respectively, and FTIR wavenumber of O-H functional group of quercetin was shifted from its original position at 3411 to 3428 cm-1 in the physical mixture (pm) of Qu-Ma and 3418 cm-1 in Co Qu-Ma, respectively. The physicochemical characterizations using DTA, PXRD, SEM and FTIR indicated that Co Qu-Ma were successfully obtained through solvent evaporation method. The in-vitro dissolution rate of Co Qu-Ma was 95.30% at 60 min. Cocrystals effectively increased dissolution rate and dissolution efficiency in comparison to the pure quercetin and physical mixture of quercetin-malonic acid.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.28511
      Issue No: Vol. 18, No. 3 (2018)
       
  • Synthesis of Poly(methyl methacrylate)-b-poly(N-isopropylacrylamide) Block
           Copolymer by Redox Polymerization and Atom Transfer Radical Polymerization
           

    • Authors: Melahat Göktaş, Guodong Deng
      Pages: 537 - 543
      Abstract: Poly(methyl methacrylate)-b-poly(N-isopropylacrylamide) [PMMA-b-PNIPAM] block copolymers were obtained by a combination of redox polymerization and atom transfer radical polymerization (ATRP) methods in two steps. For this purpose, PMMA macroinitator (ATRP-macroinitiator) was synthesized by redox polymerization of methyl methacrylate and 3-bromo-1-propanol using Ce(NH4)2(NO3)6 as a catalyst. The synthesis of PMMA-b-PNIPAM block copolymers was carried out by means of ATRP of ATRP-macroinitiator and NIPAM at 60 °C. The block copolymers were obtained in high yield and high molecular weight. The characterization of products was accomplished by using multi instruments and methods such as nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, gel permeation chromatography, and thermogravimetric analysis.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.28645
      Issue No: Vol. 18, No. 3 (2018)
       
  • Simultaneous Analysis of 6-Mercaptopurine, 6-Methylmercaptopurine, and
           6-Thioguanosine-5’-monophosphate in Dried Blood Spot Using Ultra
           Performance Liquid Chromatography Tandem Mass Spectrometry

    • Authors: Supandi Supandi, Yahdiana Harahap, Harmita Harmita, Rizka Andalusia
      Pages: 544 - 551
      Abstract: 6-Mercaptopurine is a chemotherapeutic agent of the antimetabolite class. This study aims to analyze simultaneous validation of 6-mercaptopurine (6-MP), 6-methylmercaptopurine (6-MMP), and 6-thioguanosine-5’-monophosphate (6-TGMP) in dried blood spot (DBS) using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). An accurate volume of 60 μL blood was spotted onto DBS-CAMAG paper and then extracted using methanol 90% (v/v) containing an internal standard of 5-fluorouracil (5-FU). Separation was performed using a Waters Acquity UPLC BEH AMIDA column 1.7 μm (2.1 x 100 mm) with a mobile phase mixture of 0.2% (v/v) formic acid in water−0.1% (v/v) formic acid in acetonitrile-methanol with gradient elution and flow rate of 0.2 mL/min. Mass detection was done using Waters Xevo TQD with positive electrospray ionization (ESI) for 6-MP, 6-MMP, 6-TGMP and negative ESI for 5-FU, in multiple reaction monitoring mode. Detection rates of 6-MP, 6-MMP, 6-TGMP and 5-FU were m/z 153.09 > 119.09; 167.17 > 126.03; 380.16 > 168.00); 129.09 > 42.05, respectively. This method is linear across the range 25.5–1020 ng/mL for 6-MP, 6-MMP and 6-TGMP. This method is valid for the in vitro simultaneous analysis of 6-MP, 6-MMP and 6-TGMP in DBS, based on European Medicine Agency guidelines.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.31116
      Issue No: Vol. 18, No. 3 (2018)
       
  • Bulk Polymerization Kinetics of Hydroxy Terminated Polybutadiene and
           Toluene Diisocyanate with Infrared Spectroscopy

    • Authors: Heri Budi Wibowo, Widhi Cahyo, Ratih Sanggra
      Pages: 552 - 559
      Abstract: A study on bulk polymerization kinetics of HTPB (Hydroxy Terminated Polybutadiene) and TDI (Toluene Diisocyanate) with infrared (IR) spectroscopy has been conducted. The investigations included the molar ratio of 2,4-TDI to 2,6-TDI isomers, the initial molar ratio of isocyanate group to a hydroxyl group, and the reaction temperature. The polymerization rate constant was calculated based on the decrease rate of TDI. Kinetics model had been evaluated through the following reaction steps: (1) 2,4-urethane production, (2) 2,6-urethane production, (3) the reaction between 2,4-urethane and the isocyanate group of 2,4-TDI, (4) the reaction between 2,4-urethane and the isocyanate group of 2,4-TDI, (5) the reaction between 2,6-urethane and isocyanate group of 2,4-TDI, and (6) the reaction between 2,6-urethane and the isocyanate group of 2,6-TDI. Those reaction steps were assumed to be the first order reaction with the reaction rate constants k1, k2, k3, k4, k5, and k6, respectively. The reaction rate constants obtained at molar ratio of 2,4-TDI to 2,6-TDI of 80:20, isocyanate group to hydroxyl group (RNCO/OH) initial molar ratio of 1:1, and reaction temperature of 40 °C were 6.2 × 10-5, 5.8 × 10-5, 3.1 × 10-5, 2.8 × 10-5, and 2.5 × 10-5 L.mole-1.min-1 for k1, k2, k3, k4, k5, and k6, respectively, with the activation energy of 1152, 952, 1001, 656, and 1001 kJ/mole for reaction (1)–(6), respectively. The results show that the polymerization reaction rate-determining step was the reaction of 2,6-urethane and isocyanate group of 2,6-TDI (reaction (6)).
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.24807
      Issue No: Vol. 18, No. 3 (2018)
       
  • Heat Treatment of Pitch Obtained from Atmospheric Fixed-Bed Coal
           Gasification

    • Authors: Phiciato Phiciato, Ika Monika, Arie Hardian
      Pages: 560 - 565
      Abstract: A medium temperature pitch obtained from atmospheric fixed-bed gasifier was distilled at a various time (1, 2, 3 and 4 h) to induce polymerization and the results were compared with a commercial pitch. Aromaticity level of pitches was examined using infrared spectroscopy, elemental analysis and simultaneous thermal analysis (TG-DSC). Longer heating time promoted lower moisture content, lower residue yield, higher insoluble fractions, as well as higher ash and carbon content. Although prolonged heat treatments lead to higher aromatization, there was no significant change in aromatization for heat treatment longer than 1 h. The index of aromaticity measured by using elemental analysis was ranged between 0.47 to 1.01, while the result from FTIR spectra showed stagnant value at 0.52. These values were slightly higher than that of pressurized Sasol-Lurgi gasification pitch (0.27).
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.31731
      Issue No: Vol. 18, No. 3 (2018)
       
  • Finding a Potential Bruceine D Inhibitor for Apoptotic Resistance Protein
           Pancreatic Cancer Based on Molecular Docking

    • Authors: Armi Wulanawati, Harry Noviardi, Muhamad Sholehuddin Malik Ibrohim
      Pages: 566 - 572
      Abstract: Pancreatic cancer arises when cells in the pancreas begin to multiply out of control. In pancreatic cancer, over expression of heat proteins (Hsp70, Hsp 90), constitutive activation of NFĸB, and Bcl-2 family are closely linked with resistance to apoptosis. Apoptotic resistance has been attributed to defects in apoptotic signaling pathways. Bruceine D, which found in abundance Brucea javanica, possesses potent anti-pancreatic cancer activity. In vitro result, bruceine D could induce apoptosis of pancreatic cancer cell. The aim of this study was to find the potential effect of bruceine D inhibitor on apoptotic resistance proteins in pancreatic cancer based on molecular docking. Docking showed a binding affinity between bruceine D with proteins involved in apoptosis using AutoDock. The results showed that free binding energy of Hsp70 is -5.19; Hsp90 -7.26; NFĸB1 -5.49; NFĸB2 -6.14; Bcl-W -6.02; Bcl-xL -5.45 kcal/mol. Based on the result, we conclude that bruceine D with Hsp90 protein has potential the best binding affinity than other proteins.
      PubDate: 2018-08-30
      DOI: 10.22146/ijc.25220
      Issue No: Vol. 18, No. 3 (2018)
       
 
 
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