Claim Missing Document
Check
Articles

Found 8 Documents
Search

On the Development of a Nomogram for Alkali Activated Fly Ash Material (AAFAM) Mixtures Simatupang, Partogi H.; Imran, Iswandi; Pane, Ivindra; Sunendar, Bambang
Journal of Engineering and Technological Sciences Vol 47, No 3 (2015)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (821.159 KB) | DOI: 10.5614/j.eng.technol.sci.2015.47.3.1

Abstract

Alkali activated fly ash material (AAFAM) has become the most promising material to substitute materials based on ordinary Portland cement (OPC). However, there is no available nomogram for AAFAM mixtures. In contrast, there are many rational methods available in the literature to make paste, mortar and concrete with OPC based materials, such as Monteiro-Helene’s nomogram, which uses Abram’s law, Lyse’s law and Molinari’s law. This paper presents a study to construct such a nomogram for AAFAM mixtures by first conducting experiments on the  paste and mortar phases. The procedure of Monteiro-Helene’s nomogram was adopted in this formulation. The first step in this direction was to find a close relationship between the strength and paste composition of the material that can be used as a substitute for Abram’s law. The second step  was  to construct the equivalent  of  Lyse’s and Molinari’s relationships by varying the sand and fly ash contents. The results show that it is possible to make a nomogram for AAFAM mixtures such as the one for OPC based materials. Class F fly ash and its mortar phase were used to construct the nomogram. In addition, the  mortar  samples  that were  used to build the nomogram had similar solidification products according to their microscopic characteristics.
PENGGUNAAN TiO2 PARTIKEL NANO HASIL SINTESIS BERBASIS AIR MENGGUNAKAN METODA SOL-GEL PADA BAHAN KAPAS SEBAGAI APLIKASI UNTUK TEKSTIL ANTI UV Komalasari, Maya; Sunendar, Bambang
Arena Tekstil Vol 28, No 1 (2013)
Publisher : Arena Tekstil

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2135.385 KB)

Abstract

Partikel nano TiO2 berbasis air dengan pH basa telah berhasil disintesis dengan menggunakan metode sol-gel dan diimobilisasi pada kain kapas dengan menggunakan kitosan sebagai zat pengikat silang. Sintesis dilakukan  dengan prekursor TiCl4 pada konsentrasi 0,3 M, 0,5 M dan 1 M, dan menggunakan templat kanji dengan proses kalsinasi pada suhu 500˚C selama 2 jam. Partikel nano TiO2 diaplikasikan ke kain kapas dengan metoda pad-dry-cure dan menggunakan kitosan sebagai crosslinking agent. Berdasarkan hasil Scanning Electron Microscope (SEM),diketahui bahwa morfologi partikel TiO2 berbentuk spherical dengan ukuran nano (kurang dari 100 nm). Karakterisasi X-Ray Diffraction (XRD) menunjukkan adanya tiga tipe struktur kristal utama, yaitu (100), (101) dan (102) dengan fasa kristal yang terbentuk adalah anatase dan rutile. Pada karakterisasi menggunakan SEM terhadap serbuk dari TiO2 yang telah diaplikasikan ke permukaan kain kapas, terlihat adanya imobilisasi partikel nano TiO2 melalui ikatan hidrogen silang dengan kitosan pada kain kapas. Hasil analisa tersebut kemudian dikonfirmasi dengan FTIR (Fourier Transform Infra Red) yang hasilnya memperlihatkan puncak serapan pada bilangan gelombang 3495 cm-1, 2546 cm-1, dan 511 cm-1,  yang masing-masing diasumsikan sebagai adanya vibrasi gugus fungsi O-H, N-H dan Ti-O-Ti. Hasil SEM menunjukkan pula bahwa kristal nano yang terbentuk diantaranya adalah fasa rutile , yang berdasarkan literatur terbukti dapatberfungsi sebagai anti UV.
Evaluation on the Temperature and Calcination Time During Sol-gel Coating of TiO2 on Iron Foam substrate Ramdan, Raden Dadan; Haris, Luqman; Hermawan, Hendra; Sunendar, Bambang
Mesin Vol 26, No 1 (2017)
Publisher : Mesin

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1966.381 KB) | DOI: 10.5614/MESIN.2017.26.1.1

Abstract

Iron foam is iron based material which is widely applied due to its unique properties. However since corrosion is also a problem for this material, coating with innert material is required in enhancing its applications. In the present research, TiO2 coating is performed on iron foam suface by sol-gel dipping method. Focus is given on the study of the effect of calcinations temperature and time on the coating characteristics. TiCl4 is used as the precursor with concentration of 0.3 M, added with 1M HCl solution and chitosan soluation with concentration of 1%. Calcination is performed at temperature of 400, 500 dan 600oC and calcinations time of 1 and 3 hours inside controlled gas furnace using nitrogen atmosphere. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) characterization data shows that TiO2 particles form on the iron foam substrate. SEM characterization on the sample heated at 400oC and heating time of 1 hour shows the formation of nano particle titania (0.06 μm) which is homogeneously distributed with less agglomeration than others and considered as the best sample in the present research. As the temperature and time of calcinations increase, more inhomogeneous particle distribution and bigger particles form.
Hardness evaluation of dental composites fabricated from the uniform size and well-distributed zirconia-alumina-silica fillers with sol-gel technique Hakim, Muhammad Lukman Nur; Hasratiningsih, Zulia; Djustiana, Nina; Sunendar, Bambang; Faza, Yanwar
Padjadjaran Journal of Dentistry Vol 30, No 2 (2018): July
Publisher : Faculty of Dentistry Universitas Padjadjaran, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (433.347 KB) | DOI: 10.24198/pjd.vol30no2.18319

Abstract

Introduction: Several factor limits of services of dental composite have triggered further improvement. ZrO2-Al2O3-SiO2 system as filler of dental composite had been developed with sol-gel technique. Ultrasonic homogeniser were reported to change the particle size ditribution or shape. Unifom size and distribution of particle is believed to help define the behavior of hardness properties. Methods: The study was an laboratory experimental design. Filler ZrO2-Al2O3-SiO2 system were developed via sol-gel methods. Post calcination process, filler were immerse in ethanol and applied with ultrasonic homogeniser, with various amplitude i.e 50 rpm, 60 rpm and 80 rpm then named sample A, B, and C. XRD, SEM anda PSA were used to characterize of filler system. Subsequent filler were used to fabricate dental composite then evaluate the hardness value using micro-hardness tester. One–way ANOVA was used to analysis the statistical result of hardness value. Results: XRD pattern of three sample were similar in which tetragonal zirconia was prominent (57-61 %) followed by monoclinic zirconia (24-25%) and amorphous (15-17 %). While, SEM and PSA characterization showed amplitude 50 rpm (sample A) produce more uniform size and well-distributed particle filler than the others. In contrary, sample B and C showed higher peak in PSA results. It means there was dominating of filler with particular size.  However, the hardness value did not show significant differences between those filler (p>0,05). Conclusion: Dental composite that contain of different uniformity and distribution of filler ZrO2-Al2O3-SiO2 system has no significantly differences of hardness value.
ADDITION OF RICE HUSK NANOCELLULOSE TO THE IMPACT STRENGTH OF RESIN BASE HEAT CURED Hasran, Muhammad Aditya Ramadhan; Imam, Dian Noviyanti Agus; Sunendar, Bambang
Journal of Vocational Health Studies Vol. 4 No. 3 (2021): March 2021 | JOURNAL OF VOCATIONAL HEALTH STUDIES
Publisher : Faculty of Vocational Studies, Universitas Airlangga

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jvhs.V4.I3.2021.119-124

Abstract

Background: One of the materials for denture bases is heat-cured acrylic resin (PMMA). This material still lacks impact strength as a mechanical strength property. The addition of reinforcing material is known to increase the mechanical strength of PMMA. One of the reinforcing materials added to PMMA is nano cellulose from rice husks, one of the wastes from agricultural products. Purpose: This study aims to determine rice husk nano cellulose's addition to the PMMA denture base's impact strength. Method:  The research sample consisted of six groups, each group consisting of 8 samples selected by simple random. The PI, P2, P3, P4, P5, and K groups were PMMA with 1%, 2%, 3%, 4%, 5% nano cellulose, and without nano cellulose. Result: Mean impact strength test results were 41.50 x 10-3 ± 3.891 J / mm2 for P1, 44.13 x 10-3 ± 3,980 J / mm2 for P2, 45.63 x 10-3 ± 4,438 J / mm2 for P3, 46.87 x 10-3 ± 4,824 J / mm2 for P4, 49.12 x 10-3 ± 4.016 J / mm2 for P5 and 36.25 x 10-3 ± 1.982 J / mm2 for K. One way Anova test results with p-value of 0.000 indicates differences in the six groups (p<0.05). Conclusion: This study concludes that the impact strength value of PMMA with the addition of rice husk nano cellulose has increased compared to the control group without the addition of rice husk nano cellulose.
Characterization and Drug Release Evaluation of Chlorhexidine-Encapsulated Silica Nanoparticles for Potential Root Canal Disinfection Rakhmawati, Widya; Harmaji, Andrie; Djati, Fanni Kusuma; Sunendar, Bambang
Makara Journal of Science Vol. 29, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The failure of root canal treatments is often attributed to bacterial invasion of the dentinal tubules, where pathogens can persist and complicate healing. Chlorhexidine digluconate, a potent antimicrobial agent, has been widely utilized for its broad-spectrum antibacterial effects. However, challenges remain in achieving efficient distribution and sustained release within the root canal system. This study investigates the encapsulation of chlorhexidine digluconate within silica nanoparticles as a novel drug delivery system that is aimed at improving root canal treatment outcomes. Silica nanoparticles were synthesized using the sol-gel method and subsequently immersed in a 2% chlorhexidine digluconate solution for 15 to 30 minutes to achieve encapsulation. The resulting materials were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and ultraviolet–visible (UV–Vis) spectroscopy. SEM analysis revealed particle sizes in the range of 80–150 nm for nanoparticles aged for 15 minutes and in the range of 250–350 nm for those aged for 30 minutes. FTIR spectroscopy confirmed the presence of functional groups characteristic of silica, chitosan, and sodium alginate, indicating successful encapsulation. The UV–Vis spectrophotometry demonstrated that silica nanoparticles aged for 30 minutes exhibited a more stable and controlled release of chlorhexidine digluconate (0.08 ppm) over a 60-minute period. This study presents a novel approach for enhancing root canal treatment, in which silica nanoparticles are utilized for controlled drug delivery. Additionally, the study shows that longer aging times may offer improved stability and efficacy in sustained antimicrobial action. The findings suggest that the use of silica-encapsulated chlorhexidine nanoparticles is a promising strategy for more effective endodontic treatment because it addresses bacterial invasion and supports long-term therapeutic effects.
Hardness evaluation of dental composites fabricated from the uniform size and well-distributed zirconia-alumina-silica fillers with sol-gel technique Hakim, Muhammad Lukman Nur; Faza, Yanwar; Hasratiningsih, Zulia; Djustiana, Nina; Sunendar, Bambang
Padjadjaran Journal of Dentistry Vol 30, No 2 (2018): July 2018
Publisher : Faculty of Dentistry Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (433.347 KB) | DOI: 10.24198/pjd.vol30no2.18319

Abstract

Introduction: Several factor limits of services of dental composite have triggered further improvement. ZrO2-Al2O3-SiO2 system as filler of dental composite had been developed with sol-gel technique. Ultrasonic homogeniser were reported to change the particle size ditribution or shape. Unifom size and distribution of particle is believed to help define the behavior of hardness properties. Methods: The study was an laboratory experimental design. Filler ZrO2-Al2O3-SiO2 system were developed via sol-gel methods. Post calcination process, filler were immerse in ethanol and applied with ultrasonic homogeniser, with various amplitude i.e 50 rpm, 60 rpm and 80 rpm then named sample A, B, and C. XRD, SEM anda PSA were used to characterize of filler system. Subsequent filler were used to fabricate dental composite then evaluate the hardness value using micro-hardness tester. One–way ANOVA was used to analysis the statistical result of hardness value. Results: XRD pattern of three sample were similar in which tetragonal zirconia was prominent (57-61 %) followed by monoclinic zirconia (24-25%) and amorphous (15-17 %). While, SEM and PSA characterization showed amplitude 50 rpm (sample A) produce more uniform size and well-distributed particle filler than the others. In contrary, sample B and C showed higher peak in PSA results. It means there was dominating of filler with particular size.  However, the hardness value did not show significant differences between those filler (p>0,05). Conclusion: Dental composite that contain of different uniformity and distribution of filler ZrO2-Al2O3-SiO2 system has no significantly differences of hardness value.
Impact of Reduced Activator Concentration and Curing Method on Compressive Strength of Metakaolin/Fly Ash-based Geopolymer Mortar Harmaji, Andrie; Haimir, Alexander Syahlendra; Sunendar, Bambang
Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol. 14 No. 1 (2023): May
Publisher : Balai Besar Standardisasi dan Pelayanan Jasa Pencegahan Pencemaran Industri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21771/jrtppi.2023.v14.no1.p19-28

Abstract

The demand for cement is increasing each year, but the manufacture of 1 tonne of cement produces an equal number of carbondioxide (CO2) gas which is directly related to the increase in global warming. Therefore, we need a substitute material, namely geopolymer. This material has relatively superior properties compared to cement. However, one of the drawbacks of geopolymers is that the production costs are relatively more expensive compared to the manufacture of pre-cast cement because it requires chemical solutions such as sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) to activate the precursor. This research was conducted to replace a specific ratio of alkali activator with water to reduce the use of alkaline hydroxide solutions and sodium silicate while reducing production costs. The experiment was carried out by replacing the activator solution with water at a certain amount with a different curing method. Mechanical properties, X-Ray Diffraction (XRD), and Fourier Transform Infrared (FTIR) spectroscopy characterization were used to analyze the effect of additional water in geopolymer. The compressive test result shows that the maximum water content that can replace the activator solution is 20% by activator mass for fly ash-based geopolymers and 30% by activator mass for metakaolin-based geopolymers, with sealed and bare curing conditions before the compressive strength was decreased sharply. Substitution of 10% water in fly ash-based geopolymer increases the compressive strength to 17.20 MPa. Compressive test results and characterization showed that the optimal curing condition for fly ash-based geopolymer was sealed curing and bare curing for metakaolin-based geopolymer. The strength increase is due to O-C-O bonds representing sodium carbonate (Na2CO3), which affects the compressive strength of fly ash-based and metakaolin-based geopolymers.