Papers by Rina Dewi Mayasari
THE INTERNATIONAL CONFERENCE ON ADVANCED MATERIAL AND TECHNOLOGY (ICAMT) 2021
Now days, the growth of composite housing in the earthquake-prone areas has increased significant... more Now days, the growth of composite housing in the earthquake-prone areas has increased significantly. Composite sandwich panel is the main component of the house wall. The properties of composite sandwich depend on the behavior of the two thin glass fiber reinforced polymer (GFRP) face sheets [7] and a lightweight core as the layer components. This work focused on the fabrication and characterization of sandwich-structured glass fiber reinforced polymer (GFRP) composites filled expanded polystyrene (EPS) and polyurethane (PU) foam cores. The main objectives are to analyze the effect of the different kind of cores on the panel mechanical properties, such as the flexural and compressive strength. The test results revealed that PU sandwich has flexural strain of 77.33% higher than that of the EPS-based. Thus, it was found that the performance of PU-foam sandwich panel composite shows better than that of the EPS panel.
Surface Plasmon Resonance Sensor Based on Kretschmann Configuration for Dengue Virus Detection
2022 International Conference on Radar, Antenna, Microwave, Electronics, and Telecommunications (ICRAMET)
Jurnal Inovasi dan Teknologi Material, 2020
Pemurnian gliserin dilakukan dengan tiga tahapanreaksi yaitu: acidification,polar solven extract... more Pemurnian gliserin dilakukan dengan tiga tahapanreaksi yaitu: acidification,polar solven extraction, dan activated carbon adsoption. Proses pemurnian juga mengoptimasi pengaruh jenis asam (H3PO4, H2SO4dan CH3COOH) pada pH (1–6), jenis pelarut / polar solvent(CH3OH, C2H5OH dan C3H7OH) dengan rasio pelarut organik terhadap gliserin (3:1–1:3 v/v), serta proses adsorpsi karbon aktif dengan perbandingan konsentrasi karbon aktif terhadap gliserin (40–200 g/l).Pemurnian crude glycerin(±82% PT. Wilmar Nabati) telah dilakukan dengan proses adsorpsi karbon aktif lokal.Proses adsorpsi bertujuan untuk menghilangkan senyawa MONG (matter organic non glycerin) dan betha-carotenesebagai komponen warna.Setelah proses adsorpsi diperoleh gliserin dengan kemurnian ±96% (b/v). Untuk mendapatkan kemurnian mencapai 99,8% diperlukan proses distilasi untuk memisahkan impuritas air.
THE 2ND SCIENCE AND MATHEMATICS INTERNATIONAL CONFERENCE (SMIC 2020): Transforming Research and Education of Science and Mathematics in the Digital Age, 2021
Microcantilever is a device of MEMS (microelectro-mechanical system) which can be used as a bioch... more Microcantilever is a device of MEMS (microelectro-mechanical system) which can be used as a biochemical sensor, such as to determine the characteristics of chemical liquids. In this work, an investigation of evaporation rate of chemical liquids, i.e., ethanol, methanol, and propanol, was carried out using resonant frequency change of vibrated microcantilever. We used two types of microcantilever, namely uncoated-microcantilever (reference) and ZnO-coated microcantilever. A growth of ZnO nanorods on microcantilever was carried out by hydrothermal method through 2 stages, i.e., a coating of seed (seeding) and growth of ZnO rods. The seed layer was deposited by dip-coating method from the solution of zinc nitrate tetrahydrate (ZNT) and dietanolamine (DEA) in ethanol. ZnO nanorods were then grown by hydrothermal method from the solution of zinc nitrate tetrahydrate (ZNT) and hexamethylenetetramine (HMTA) in demineralized water at 80°C for 2 hours. The experimental results show that, the resonant frequency of uncoated-microcantilever before dropping ethanol was measured of 36.80 kHz. After dropping ethanol on the microcantilever, the resonant frequency raised to 36.84 kHz. From the resonant frequency data, the evaporation rate of ethanol can be calculated to be 0.150 picogram/minute. Moreover, the evaporation rate of methanol and propanol was obtained 0.149 picogram/minute and 0.149 picogram/minute, respectively. For ZnO-coated microcantilever, the resonant frequencies before and after dropping propanol reveal the value of 13.98 kHz and 12.33 kHz, respectively. However, the resonant frequency did not return to the initial value after ethanol dropping, indicating that the propanol molecule reacts with the ZnO surface and remains on the surface.
Diterima 10 Januari 2019 Direvisi 29 Maret 2019 Disetujui 20 November 2019 Nomor Artikel 201906 H... more Diterima 10 Januari 2019 Direvisi 29 Maret 2019 Disetujui 20 November 2019 Nomor Artikel 201906 Halaman 1-6 Purification of glycerin has been done by using three phases of reaction, i.e. acidification, polar solvent extraction, and activated carbon adsorption. Purification process optimized the effects of the types of acids (H3PO4, H2SO4 dan CH3COOH) on pH (1-6), solvent / polar solvent (CH3OH, C2H5OH and C3H7OH) with ratio of solvent to glycerin (3: 1-1: 3 v / v), and adsorption process using activated carbon with ratio of activated carbon concentration to glycerin (40-200 g / l). Purification of crude glycerin (±82% PT. Wilmar Nabati) has been done by adsorption process using local activated carbon. Adsorption process using activated carbon aims to remove MONG compounds (matter organic non glycerin) and betha-carotene as color component. After adsorption process, we obtained glycerin with ±95% ( b /v) in purity. To achieve purity of 99.8%, it needs to separate the water impurities...
Seng oksida (ZnO) rods murni dan terdoping serium oksida (CeO 2 ) telah ditumbuhkan di atas subst... more Seng oksida (ZnO) rods murni dan terdoping serium oksida (CeO 2 ) telah ditumbuhkan di atas substrat kaca dengan menggunakan metode hidrotermal. Penumbuhan ZnO rods memiliki dua tahapan proses utama, yaitu pelapisan seed (pembenihan) dan penumbuhan rods . Rasio konsentrasi Ce/ZnO adalah sebesar 1%, 5%, dan 10%. Efek dopan CeO 2 pada struktur dan morfologi ZnO rods dianalisa dengan X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersion X - ray (EDX), dan Fourier transform infrared (FTIR). Spektrum XRD dari ZnO rods murni dan terdoping CeO 2 memiliki fasa hexagonal wurtzite ZnO dengan tiga puncak tertinggi pada bidang kisi (100), (002), (101), serta fasa face-centered cubic CeO 2 pada bidang kisi (111) dan (200). Hasil analisis SEM mengonfirmasi bahwa bentuk ZnO murni dan terdoping CeO 2 adalah gumpalan hexagonal flower-like rods . Penambahan CeO 2 telah menggeser puncak spektrum FTIR ZnO murni dari 729 cm -1 menjadi ~780 cm -1 .
The microcantilever sensor is one of the most generally studied and learned sensors currently on ... more The microcantilever sensor is one of the most generally studied and learned sensors currently on the fields of chemistry, biology, health and environmental factors such as temperature, humidity, sound and pressure. This is because the microcantilever sensor has a high sensitivity to the attogram scale (10−18). The Q factor of the microcantilever sensor illustrates the sensitivity of the sensor. This research was carried out in 48% and 55% humidity variations with the chamber opened and closed. The results showed that the higher of humidity, degrades the Q factor in the microcantilever sensor. The average value of the Q factor when chamber was opened at 48% humidity was 285.2 and 240.9 at 55%. When the chamber is closed at the 48% of humidity has an average Q factor in 266.7 and 243.3 at 55%. This is due to water molecules attached to the microcantilever sensor when humidity is high causes a decrease of the resonant frequency in the microcantilever sensor where the Q factor has an eq...
Arena Tekstil, 2020
Serat tekstil dengan bahan baku poliester merupakan komoditas produksi serat terbesar di antara s... more Serat tekstil dengan bahan baku poliester merupakan komoditas produksi serat terbesar di antara serat sintetik lainnya. Penelitian ini telah berhasil membuat serat poliester dengan pencampuran bahan baku polyethylene terephthalate (PET) dan produk komersial senyawa turunan fosfinat dengan variasi konsentrasi 0%; 0,25%; 0,50%; dan 1,00%. Serat poliester termodifikasi dikarakterisasi menggunakan alat Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), dan universal testing machine (UTM) 2 kN. Spektrum IR mengonfirmasi bahwa gugus fungsi dari PET dan senyawa kimia (fosfinat, seng oksida, dan magnesium fosfat) terbentuk pada sampel serat. Analisis sifat termal mengindikasikan bahwa penambahan senyawa kimia dengan konsentrasi 1,00% telah meningkatkan sifat termal serat poliester dengan suhu degradasi pada rentang 260-300°C dan titik leleh pada suhu 390°C. Sementara itu, hasil uji tarik menunjukkan bahwa semakin tinggi konsentrasi zat aditif meningkatkan sifat rapuh serat PET.
Metalurgi, 2020
Sintesis nano-perovskite oksida neodimium besi (NdFeO 3) telah berhasil dilakukan dengan metode p... more Sintesis nano-perovskite oksida neodimium besi (NdFeO 3) telah berhasil dilakukan dengan metode presipitasi menggunakan surfaktan EG (ethylene glycol) sebagai material pelapis. Senyawa NdFeO 3 dikarakterisasi analisis gugus fungsi kimia dengan FTIR (fourier transform infrared spectroscopy), analisis morfologi dengan SEM (scanning electron microscopy), analisis kristalinitas dan ukuran partikel dengan XRD (X-ray diffraction) dan TEM (transmission electron microscopy). Pengamatan SEM dan TEM menunjukkan bahwa hasil sintesis membentuk nanostruktur berbentuk bulat dengan ukuran diameter pada rentang 15 sampai 20 nm. Spektra XRD mengonfirmasi bahwa fasa NdFeO 3 membentuk struktur orthorombik dan perovskite.
Malaysian Journal of Fundamental and Applied Sciences, 2020
Zinc oxide (ZnO) nanorods have been grown on different substrates, i.e. gold film-coated BK-7 gla... more Zinc oxide (ZnO) nanorods have been grown on different substrates, i.e. gold film-coated BK-7 glass (Au-film/BK7), microscope glass slide (MGS), silicon oxide film-coated silicon (SiO2-film/Si), to investigate the effects of different substrates on its material properties. The growth process was started by dipping substrates in zinc acetate solution to fabricate a seed layer, followed by growing the ZnO nanorods in zinc nitrate tetrahydrate solution based on hydrothermal method at 95 °C for 6 hour. In this process, seed layer and ZnO nanorods were annealed at 350 °C for 2 hours. The characterization results using X-ray diffraction and field effect scanning electron microscope showed that ZnO nanorods were successfully grown homogenously and mostly in vertical direction with hexagonal wurtzite structure. The diameter size of ZnO nanorods was significantly influenced by the type of material substrate. ZnO nanorods on Au-film/BK-7 glass have the smallest diameter size of (239±51) nm, w...
SPEKTRA: Jurnal Fisika dan Aplikasinya, Aug 31, 2017
Pada riset ini, batang ZnO (Zinc Oxide rods) yang merupakan material pendeteksi objek gas ditumbu... more Pada riset ini, batang ZnO (Zinc Oxide rods) yang merupakan material pendeteksi objek gas ditumbuhkan di atas permukaan mikrokantilever dengan teknik hidrotermal. Sintesis ZnO rods ini meliputi dua proses, yaitu proses pelapisan lapisan benih (seed layer) menggunakan Zinc Asetate Dihydrate dengan metode dip-coating dan proses penumbuhan ZnO rods menggunakan Zinc Nitrate Tetrahydrate pada suhu 95 °C dengan variasi waktu 2 jam, 4 jam dan 6 jam. Kondisi pengeringan baik untuk lapisan benih dan penumbuhan ZnO rods dilakukan pada suhu 120 °C selama 2 jam. ZnO rods dikarakterisasi dengan teknik Fourier Transform Infrared (FTIR) untuk mengetahui pembentukan ikatan Zn-O. Hasil karakterisasi memperlihatkan bahwa korelasi logam oksida (metal oxide) ditunjukkan pada spektrum bilangan gelombang 540 cm-1 untuk waktu penumbuhan 2 jam, sementara ditunjukkan pada spektrum gelombang masing-masing 548 cm-1 dan 547 cm-1 untuk waktu penumbuhan ZnO rods 4 jam dan 6 jam. Spektrum bilangan gelombang sekitar 540-548 cm-1 tersebut diprediksi merupakan absorpsi dari pembentukan ikatan Zn-O.
Jurnal Fisika Indonesia, 2020
Pengamatan fenomena surface plasmon resonance (SPR) telah berhasil dilakukan pada ZnO nanorods ya... more Pengamatan fenomena surface plasmon resonance (SPR) telah berhasil dilakukan pada ZnO nanorods yang ditumbuhkan di atas lapisan tipis emas. Sistem SPR menggunakan konfigurasi Kretschmann termodifikasi dimana permukaan prisma dideposisi dengan lapisan tipis emas dan ZnO nanorods (prisma/Au/ZnO). Penumbuhan ZnO nanorods menggunakan metode hidrotermal dengan dua tahapan, yaitu pelapisan ZnO seed dan penumbuhan rods. Waktu penumbuhan divariasikan selama 5 menit, 2 jam, dan 4 jam, pada suhu 95 °C yang diikuti dengan annealing pada suhu 500 °C selama 1 jam. Struktur ZnO dikarakterisasi dengan X-ray diffraction (XRD), field emission scanning electron microscope - energy dispersive X-ray spectroscopy (FESEM-EDS), serta diamati fenomena SPR melalui grafik attenuated total reflection (ATR). Hasil karakterisasi menunjukkan bahwa ZnO nanorods (2 jam dan 4 jam) memiliki struktur kristal heksagonal dengan distribusi ukuran diameter pada rentang 20 nm – 60 nm. Fenomena SPR hanya teramati pada nano...
Jurnal Fisika Indonesia, 2017
Pergeseran sudut surface plasmon resonance (SPR) pada konfigurasi Kretschmann-perak termodifikasi... more Pergeseran sudut surface plasmon resonance (SPR) pada konfigurasi Kretschmann-perak termodifikasi oleh nanopartikel cobalt ferrite (CoFe2O4) telah dikaji secara eksperimen di bawah pengaruh medan magnet. Tiga sampel nanopartikel CoFe2O4 dengan ukuran partikel yang berbeda, yaitu 1,68 nm untuk sampel A; 1,95 nm untuk sampel B; dan 5,87 untuk sampel C, disintesis dengan metode kopresipitasi. Pendeposisian tiga sampel menggeser sudut SPR referensi (prisma/Ag) dengan nilai yang berbeda-beda, yaitu sebesar 0,10°; 0,10°; dan 0,30°, dengan ketidakpastian masing-masing sebesar ±0,05° untuk sampel A, B, dan C secara berturut-turut. Setelah dikenai medan magnet luar,sudut SPR bergeser lagi sejauh 0,30° untuk sampel A dan B, dan 0,5° untuk sampel C, dengan ketidakpastian masing-masing sebesar ±0,05°. Selain itu, perbedaan dua arah medan magnet terkonfirmasi bahwa pergeseran sudut SPR memiliki nilai yang berbeda, yaitu 0,3°±0,05° dan 0,6°±0,05°. Respon nanopartikel CoFe2O4 pada pergeseran sudut...
Spektra: Jurnal Fisika dan Aplikasinya, 2019
Cerium oxide (CeO2) and Neodymium oxide (Nd2O3) nanoparticles using local content have been synth... more Cerium oxide (CeO2) and Neodymium oxide (Nd2O3) nanoparticles using local content have been synthesized by precipitation method. The CeO2 and Nd2O3 nanoparticles were characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) to analyze the material phase and structure. The XRD spectrum shows that CeO2 and Nd2O3 nanoparticles have face-centered cubic and hexagonal, and cubic, respectively. The anti-microbial activity of CeO2 and Nd2O3 nanoparticles was analyzed by diffusion method using gram-negative bacteria (E.coli, S.aeureus, P. aeruginosa), and gram-positive bacteria (S. entericatyphi, L. monocyogenes), and fungus (C. albicans). The result confirms that CeO2 and Nd2O3 nanoparticles have the capability of patogen microbia inhibition. The CeO2 nanoparticles have the effective activities of inhibition for the microbia of S. aereus and S. entericatyphi, whereas Nd2O3 nanoparticles can inhibit the microbia of P. aeruginosa, S. entericatyphi, and L. monocyogenes.
THE 8TH NATIONAL PHYSICS SEMINAR 2019, 2019
Environmental monitoring has been one of the key to provide better safety measure in various sect... more Environmental monitoring has been one of the key to provide better safety measure in various sectors of life. The most famously featured technology in this area is the gas detecting system. It serves not only in an early-warning application, but also a continuous mean to provide background check of the atmospheric status of a specific area ranges. According to their principals, gas sensors can be separated into two categories; the conductive metal-oxides and the electrochemical-type, with the latter gaining more recognition over the last decade as the future standard component in any gas sensing apparatus. Within this article, the whole concept of an electrochemical gas sensor will be presented, including the basic science and the basic electronical engineering that runs the device. The main concern will be fallen onto a specific amperometric-type sensor as the most common electrochemical sensor in the market. Ultimately, since there are multiple parts that comprise a single electrochemical sensor, a special section will be written within this article to show the array of materials that are responsible to the sensing capabilities of the sensor, particularly in the area of sensitivity and selectivity of gases.
THE 8TH NATIONAL PHYSICS SEMINAR 2019, 2019
Conductivity-based sensor using interdigitated electrode (IDE) as a substrate has been studied by... more Conductivity-based sensor using interdigitated electrode (IDE) as a substrate has been studied by scientists due to its potential application for sensing devices. Synthesis of zinc oxide (ZnO) nanorods (NRs) which were doped by cerium (Ce) of 0% (pure ZnO) and 10% (ZnO/Ce) has been done on the IDE substrate. Ce-doped ZnO NRs are synthesized in two steps, i.e., deposition of seed layer and growth of Ce-doped ZnO NRs. Seed layer is coated on an IDE substrate by dip-coating method using zinc acetate dihydrate (ZnAc) and diethylamine (DEA) dissolved in 0.3 M ethylene glycol monomethyl ether. ZnO NRs is grown by hydrothermal method from solution zinc nitrate tetrahydrate (ZNT), hexamethylene-tetramine (HMT) and Ce as a dopant. I-V characteristics with various substrate temperatures at 37°C, and 150°C to 250°C have been observed for pure ZnO and ZnO/Ce samples. Even the results of I-V characteristic generally follow Ohm's law, Ce doping affects the current vs temperature dependence. Ce doping enhances a decrease in the current when the temperature is increased from 150°C to 180°C and then the current increases with increasing temperature from 180°C to 250°C. This result indicates that Ce doping modifies electrical property of ZnO crystal in high temperature, which is essential to be clarified as a basic behavior for future sensor application.
THE 8TH NATIONAL PHYSICS SEMINAR 2019, 2019
Threshold photodissociation dynamics of NO 2 studied by time-resolved cold target recoil ion mome... more Threshold photodissociation dynamics of NO 2 studied by time-resolved cold target recoil ion momentum spectroscopy
Journal of Physics: Conference Series, 2019
Zinc Oxide (ZnO) nanorods have been attracted interests as a gas molecule-catcher material in gas... more Zinc Oxide (ZnO) nanorods have been attracted interests as a gas molecule-catcher material in gas sensor applications. In this research, ZnO nanorods was grown on the surface of interdigitated electrode arrays substrate by using a hydrothermal method. The hydrothermal process consists of two steps, i.e., the seeding process and the growth of ZnO nanorods. The precursor material used in seeding process was Zinc Acetate Dihydrate (Zn(CH3COO)2.2H2O), while Zinc Nitrate Tetrahydrate (Zn(NO3)2.6H2O) was used as a precursor in the growth of ZnO nanorods. The sample was characterized by using scanning electron microscopy (SEM) and I-V Curve testing to determine the conductivity properties. SEM results show that ZnO nanorods has an average diameter of <100 nm. The result from the I-V curve with applied voltage in the range of 1-30 volt shows that the greater value of the applied voltage produces a decrease of the resistance value. The resistance value obtained at a given voltage of 1 volt is 7.8 kohm, while at a voltage of 30 volts is 0.5 kohm. The I-V curve profile indicates that interface between ZnO nanorods and Au-electrode shows a Schottky barrier characteristics. The gas effect with various parameters of CO gas concentrations, applied voltages and temperatures is under study.
Growth of zinc oxide sensitive layer on microcantilever surface for gas sensor application
2015 International Conference on Quality in Research (QiR), 2015
Microcantilever-based sensors have been demonstrated to be a high sensitive sensor in sensing app... more Microcantilever-based sensors have been demonstrated to be a high sensitive sensor in sensing application areas of chemistry, physics, biology, and biomedical. To determine the sensor selectivity, the microcantilever surface must be coated by a sensitive layer. In this work, zinc oxide (ZnO) is prepared on the microcantilever surface as a sensitive layer by employing a crystal growth method. To confirm the elemental of ZnO sensitive layer, the coated microcantilever surface is characterized by energy dispersive spectroscopy (EDS). Next, we investigate the response of microcantilever sensor to CO2 gas in dynamic mode operation. The results show that the microcantilever sensitively responds the gas, which is indicated by the change of resonance frequency. Moreover, the consistent sensing behavior with certain resonance frequency shift due to gas response over repetitive cycles is found. The quite small of response and recovery times indicate that the sensing performance of the microcantilever with ZnO sensitive layer has high repeatablility and high reproducibility.
Fabrication of ZnO/Au/prism-based surface plasmon resonance device for gas detection
2015 International Conference on Quality in Research (QiR), 2015
Surface plasmon resonance (SPR) sensing devices have attracted interest both from a fundamental p... more Surface plasmon resonance (SPR) sensing devices have attracted interest both from a fundamental physics perspective and as higly sensitive devices for detecting small chemical and biological objects. In this work, we design SPR device using a modified Kretschmann configuration for gas detection. After gold coating on the flat surface of BK-7 semicylindrical prism, ZnO microstructures which work as sensitive layer, are formed on the gold film surface. The light reflectance is measured for various angles in order to observe the SPR spectra. Next, we measure the shift of SPR angle due to response of ZnO sensitive layer to CO2 gas. It is found that the absorption of gas molecules on the sensitive layer produces the shift of SPR spectra to the higher incident angle. The change of the light reflectance due to the gas response on the time-dependent characteristics is also studied.
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Papers by Rina Dewi Mayasari