Papers by Khairurrijal Khairurrijal
El-Hekam
The issue of this research was to understanding the tradition and education model stiil exists Mu... more The issue of this research was to understanding the tradition and education model stiil exists Musthafawiyah Islamic Boarding School since exists to this nowadays. The purpose of this study is to reveal why Musthafawiyah Islamic Boarding School stiil exists in the modernity Islamic Boarding School and consistenly in existenly tradition and education model. The research is using qualitative method whit type case study. The approach in the research is using historis-fhenomenologis. Techniques in collecting data is using observation dan interview. Sources of data in the research consist of the leader, teahers, students, and workers Musthafawiyah Islamic Boarding School. Data analysis techniques use data reduction, data presentation and conclusion. The results showed that existence Musthafawiyah Islamic Boarding School because five factor, (1) Musthafawiyah Islamic Boarding School management; desirability structural Musthafawiyah Islamic Boarding School for continue of tradition the construct Syekh Musthafa Husein, construct the thought of structural Musthafawiyah Islamic Boarding School to relevant education model of Musthafawiyah in midst modernisme education, (2) the traditional factor with to defend the yellow book as hand-grip the student at traditional Muslim school, (3) the economic factor;life expense and education which a relative cheap, (4) the sincerity teachers as dedication to Musthafawiyah Islamic Boarding School without view a give the retainer, and (5) the subservience and loyality the student at traditional Muslim school as implementation from a value at to teach.
Key Engineering Materials
Composite fiber were already developed and looked promising in dentistry. PMMA, optically clear p... more Composite fiber were already developed and looked promising in dentistry. PMMA, optically clear polymer, was combined with high mechanically properties ZrO2-Al2O3-SiO2 (ZAS) ceramic powder to improve the flexural strength value of dental post prototype. ZAS powder, with ratio 60:20:20, were first prepared via sol-gel technique. Afterwards, PMMA was dissolved in acetone then incorporate with ZAS powder 1% wt to gain ZAS-PMMA composite fiber via electrospinning method. Dental post prototype were fabricated into two groups, one group contain ZAS-PMMA composite fibers and one group contain neat BisGMA, as control, with amount of each groups samples was 10. As-prepared samples were tested by Universal Testing Machine (UTM) to evaluate the flexural strength values. Based on unpaired T-test analysis (p value < 0.05), the composite fiber post is significantly higher (48.17 %) than the neat BisGMA post. ZAS-PMMA composite fiber post was potential to be used as dental endodontic post in an...
IOP Conference Series: Materials Science and Engineering
Graphene is a potential material to replace indium tin oxide (ITO) and fluorine tin oxide (FTO) a... more Graphene is a potential material to replace indium tin oxide (ITO) and fluorine tin oxide (FTO) as a transparent conductive films (TCF) due to its high conductivity and transparency. In this study, fabrication of graphene-based TCF was carried out by means of the drop-casting method, with graphite oxide as the raw material. The graphene oxide (GO) was diluted by adding 1, 3, 5, and 7 ml of distilled (DI) water. The sample was also heat treated to ensure complete reduction process. The deposited films were characterized using UV-Vis spectroscopy and I-V to investigate their optical and electrical properties. Based on the measurement results, sample with 3 ml DI water addition gives transparency and sheet resistance (Rs) of 41.01 % and 9.43 kΩ/sq, respectively. This material has a great potential to be applied as the optoelectronics material.
Materials Research Express
Nanofiber membranes were synthesized from waste high-impact polystyrene (HIPS) using electrospinn... more Nanofiber membranes were synthesized from waste high-impact polystyrene (HIPS) using electrospinning method and then applied as air filtration media. The waste HIPS precursor solution with the concentration of 20 wt.% was prepared by dissolving waste HIPS into the mixture of d-limonene and DMF solvents. Beaded or fine nanofibers could be achieved by adjusting the ratio of solvents mixture (d-limonene and DMF). Using the ratios of solvents (d-limonene: DMF) of 3:1, 1:1, and 1:3, it was obtained beaded HIPS nanofibers with the average diameter of 272 nm, beaded HIPS nanofibers with the average diameter of 937, and fine HIPS nanofibers with the average diameter of 621 nm, respectively. From the FTIR spectral analysis, it was found that the FTIR peaks of the HIPS nanofiber membranes are the same as those of the cleaned waste HIPS and there are no FTIR peaks of DMF and d-limonene solvents. These findings implied that the electrospinning process allows the recycling of waste HIPS into HIPS nanofibers without any trapped solvent phases or apparent degradation of the original material. From the contact angle measurement, it was confirmed that the HIPS nanofiber membranes are hydrophobic and the presence of the beads in the HIPS nanofiber membranes varies their contact angles. From the air-filtration test, it was shown that the fiber morphology (beaded or fine nanofibers) considerably affects the filtration performance of the membranes. The presence of beads increased the distance between the fibers so that the pressure drop decreased. Moreover, the basis weight of the membrane greatly affected the filtration efficiency. The HIPS nanofiber membrane with the basis weight of 12.22 g m?2 had the efficiency greater than 99.999%, which was equivalent to that of the HEPA filter.
Materials Today: Proceedings
Abstract Composite fibers of polyvinylpyrrolidone (PVP)/shell extract of Melinjo (SEM) have been ... more Abstract Composite fibers of polyvinylpyrrolidone (PVP)/shell extract of Melinjo (SEM) have been successfully synthesized using electrospinning method. The synthesis began by making precursor solutions of PVP/SEM at varying mass ratio between PVP and SEM 10:0, 8:2, 6:4, and 4:6. All precursor solutions were then electrospun and transformed into fibers. The results of microscope showed that as the weight fraction of SEM increased, there was gradual morphological change from fiber into beaded fibers. Subsequently, the molecular interaction within the fibers was examined by means of Fourier Transform Infrared (FTIR) spectrometer. The FTIR results confirmed that the SEM did exist in the fibers.
Jurnal Otomasi Kontrol dan Instrumentasi
Sebuah klinostat tiga dimensi (3-D) telah dirancang untuk menyediakan sebuah lingkungan dengan gr... more Sebuah klinostat tiga dimensi (3-D) telah dirancang untuk menyediakan sebuah lingkungan dengan gravitasi sangat kecil (mikrogravitasi) bagi berbagai percobaan tanpa bobot. Besarnya gravitasi berhubungan dengan kecepatan sudut dari perputaran klinostat tersebut. Dua buah rangka berbentuk segi empat di putar pada sumbu rotasi y-z dengan menggunakan dua motor DC dan kecepatannya diatur oleh mikrokontroler AT89S52 dengan menggunakan prinsip pulse width modulation (PWM). Alat ini telah diuji selama 8 jam tanpa henti untuk berbagai kecepatan sudut di bawah 17 rpm (rotation per minute). Telah didapatkan bahwa alat ini berfungsi dengan baik.
Jurnal Otomasi Kontrol dan Instrumentasi
Studi optimasi dua parameter pemintalan elektrik, yaitu tegangan listrik dan jarak nozzle-kolekto... more Studi optimasi dua parameter pemintalan elektrik, yaitu tegangan listrik dan jarak nozzle-kolektor, telah dilakukan dengan teknik algoritma genetika dalam domain [1,60] kV dan [5,25] cm serta jumlah populasi 100 buah, peluang pindah silang (pc) 0,7 dan peluang mutasi (pm) 0,5. Jejari serat seukuran 155 nm diperoleh dari hasil subsitusi nilai optimum tegangan listrik 1,83 kV dan jarak nozzle-kolektor 23,50 cm pada simulasi pemintalan elektrik yang dimodelkan oleh Reneker, dkk. Hasil optimasi ini diharapkan dapat membantu eksperimen di laboratorium.
Jurnal Otomasi Kontrol dan Instrumentasi
A current loop receiver system based on a microcontroller has been developed. The current loop re... more A current loop receiver system based on a microcontroller has been developed. The current loop receiver system can serve 8 gas sensors with 4-20 mA outputs, which are handled by employing a multiplexer. The data acquisition of the system is composed of a common operational amplifier-based current loop receiver, a CD4051 multiplexer, an ADS7822 serial analog to digital converter (ADC), and an AT89S52 microcontroller. The measured gas concentration is displayed on the 7-segments or transmitted to a personal computer via the RS232 serial communication to be processed by the Microsoft Excel. Additional functions such as gas concentration level warning and error code display are also provi ded.
Jurnal Otomasi Kontrol dan Instrumentasi
Sistem kontrol otomatik yang diterapkan untuk membatasi daya listrik telah dirancang dan dikemban... more Sistem kontrol otomatik yang diterapkan untuk membatasi daya listrik telah dirancang dan dikembangkan berbasis mikrokontroler PIC18F4520. Dalam melakukan pengontrolan, sistem tersebut menggunakan aksi kontrol on-off. Sebagai aktuator digunakan Triac beserta drivernya sedangkan sensornya menggunakan sensor arus berbasis efek Hall. Sistem tersebut dilen gkapi keypad untuk memasukkan set point arus dan peraga LCD untuk memantau arus yang terukur. Dari pengujian yang telah dilakukan, ditunjukkan bahwa sistem telah berjalan baik. Aksi kontrol PID (proporsional-integral-diferensial) disarankan menggantikan on-off untuk pengontrolan yang lebih baik.
Jurnal Otomasi Kontrol dan Instrumentasi
Telah dirancang dan dibangun alat pengukur curah hu jan tipe tipping-bucket (TB) berbasis mikroko... more Telah dirancang dan dibangun alat pengukur curah hu jan tipe tipping-bucket (TB) berbasis mikrokontroler AT89S8252. Alat ini menghasilkan tetesan 0,21 mm untuk daerah tabung kecil terpancang sebagai penerima tetesan (tipping-bucket/TB) dari kerucut penampung air hujan seluas 2837,54 mm 2. Untuk mencacah TB-nya, sensor tipe reed switch digunakan dan dibaca oleh data logger berbasis mikrokontroler AT89S8252. Data logger tersebut dilengkapi sebuah real time clock dan komunikasi serial agar dapat mengirimkan data ke komputer. Curah hujan maksimum yang bisa diukur adalah 914,4 mm/jam.
Measurement and Control
A solar simulator suitable for universities’ lab was designed and developed using a quartz tungst... more A solar simulator suitable for universities’ lab was designed and developed using a quartz tungsten halogen lamp as its light source, an alternating current phase-cut dimmer, a light intensity meter, and an ATMega328p microcontroller with a computer and a liquid crystal display. Noting that the quartz tungsten halogen lamp suffers bulb overheating and long-term degradation that leads to the decrease in its light intensity, a control mechanism was applied. The control mechanism employed a proportional–integral–differential action with Some-Overshoot Ziegler–Nichols tuning rule. It was shown that the control mechanism works well in stabilizing the quartz tungsten halogen lamp irradiance between 273 and 1182 W/m2. The developed solar simulator was then tested to obtain I-V (current–voltage) characteristics of 3 W peak and 5 W peak commercial solar panels (GH Solar, GH5P-9). Based on the gained I-V characteristics, it was shown that the obtained characteristics of the commercial solar p...
Indonesian Journal of Chemistry
In recent years, the ferroelectric properties of aurivillius oxides have attracted interest and a... more In recent years, the ferroelectric properties of aurivillius oxides have attracted interest and an extensive amount of work has been done toward the realization of their potential application in nonvolatile memories (FeRAM: ferroelectric random access memory). Recently, we have carried out computer simulation in atomic scale in order to predict the energies associated with the accommodation of aliovalent and isovalent dopants (Pb2+, Al3+, Ga3+, In3+, Ta5+) in the aurivillius structure of BaBi4Ti4O15. In this work, the predicted stable phases were synthesized using solid state reactions and their products then were characterized using powder X-ray diffraction method. The cell parameters were determined using Rietveld refinement in orthorhombic system with space group of A21am. Results from the ferroelectric properties measurement of BaBi4Ti4O15 were also presented. The cell parameters for BaBi4Ti4O15 doped with Pb2+, Al3+, Ga3+,In3+, Ta5+ were a = 5.47116(4) b = 5.45636(5) c = 41.864...
International journal of nanomedicine, 2018
α-Mangostin is a major active compound of mangosteen ( L.) pericarp extract (MPE) that has potent... more α-Mangostin is a major active compound of mangosteen ( L.) pericarp extract (MPE) that has potent antioxidant activity. Unfortunately, its poor aqueous solubility limits its therapeutic application. Purpose: This paper reports a promising approach to improve the clinical use of this substance through electrospinning technique. Polyvinylpyrrolidone (PVP) was explored as a hydrophilic matrix to carry α-mangostin in MPE. Physicochemical properties of MPE:PVP nanofibers with various extract-to-polymer ratios were studied, including morphology, size, crystallinity, chemical interaction, and thermal behavior. Antioxidant activity and the release of α-mangostin, as the chemical marker of MPE, from the resulting fibers were investigated. It was obtained that the MPE:PVP nanofiber mats were flat, bead-free, and in a size range of 387-586 nm. Peak shifts in Fourier-transform infrared spectra of PVP in the presence of MPE suggested hydrogen bond formation between MPE and PVP. The differential ...
Jurnal ILMU DASAR, 2014
Modeling of the leakage current in a field-effect transistor metal-oxide-semiconductor (MOSFET) w... more Modeling of the leakage current in a field-effect transistor metal-oxide-semiconductor (MOSFET) with high dielectric material has been developed by taking into account the effect of charge traps formed at the interface of high-k material/SiO2. Transmittance calculated using Airy wave function approach and involving the anisotropic electron mass and the effect of coupling between transverse and longitudinal energy represented by the speed of the electrons in the metal gate. Transmittance obtained is then used to calculate the leakage current in the structure of n+Poly-Si/HfSiOxN/trap/SiO2/p-Si for oxide voltage variations, temperature, and thickness of the SiO2. From the calculation that the leakage current decreases with decreasing of oxide voltage and increasing of the thickness of the oxide layer of SiO2. Also obtained that the temperature of the device does not give a great influence on the change of leakage current. Keywords: Leakage current, electron speed, charge traps
Jurnal Matematika Sains, Oct 13, 2009
... Abstrak Simulasi dinamika paket gelombang elektron saat menerobos penghalang potensial di dal... more ... Abstrak Simulasi dinamika paket gelombang elektron saat menerobos penghalang potensial di dalam dioda MOS (Metal-Oksida-Semikonduktor) telah dilakukan dengan persamaan Schrödinger yang bergantung pada waktu menggunakan teknik beda hingga. ...
Jurnal Pendidikan Fisika Indonesia, Jul 16, 2014
Sistem pemintalan elektrik jarum tunggal dan kolektor bidang memiliki kelemahan, yaitu laju produ... more Sistem pemintalan elektrik jarum tunggal dan kolektor bidang memiliki kelemahan, yaitu laju produksi yang rendah. Untuk mengatasinya digunakan sistem jarum banyak yang berjejer (multi nozel) dan kolektor berbentuk silinder berputar (kolektor drum). Banyaknya jarum dimaksudkan untuk menambah laju produksi, kolektor drum berputar dimaksudkan agar dihasilkan nanoserat dalam bentuk lembaran yang seragam. Tujuan penelitian adalah untuk menguji pengaruh medan listrik pada proses pemintalan elektrik multi nozel dan kolektor drum berputar, serta mengontrol morfologi nanoserat poli(vinil alkohol)/PVA yang dihasilkan dengan cara mengubah laju alir larutan. Hasil penelitian yang didapat adalah: (1) telah berhasil dibuat nanoserat PVA dalam bentuk lembaran yang menumpuk di kolektor drum, (2) pada pemintalan elektrik dengan sistem multi nozel terjadi distorsi medan listrik pada ujung jarum yang menyebabkan serat pada kolektor tidak rata, (3) morfologi nanoserat PVA yang dihasilkan pada laju alir 0,4 dan 0,6 ml/jam banyak mengandung butiran, sedangkan pada laju alir 0,8 ml/jam jumlah butiran berkurang. ABSTRACT Electrospinning system with single needle and planar collector has the disadvantage of a low productivity. To overcome this problem drum collector and multi-nozzle system were employed. The multi-nozzle system was used to improve the production rate, while the drum collector was used for maintaining the uniformity of the size. The purposes of this study were to examine the influence of electric field in the electrospinning process and to control the morphology of the obtained poly(vinyl alcohol)/PVA nanofibers by changing the solution flow rate. The obtained results were: (1) PVA nanofibers membrane have been successfully produced stacked on the drum collector, (2) distortion of the electric field at the tip of the needle was occurred, which results in inhomogeneous thickness of the stacked nanofibers, and (3) the morphology of the obtained nanofibers at the flow rates of 0.4 and 0.6 ml/hour have many beads while at 0.8 ml/hour the number of beads decreased.
Telah difabrikasi superkapasitor menggunakan polimer polivinil alkohol hidrogel yang mengandung g... more Telah difabrikasi superkapasitor menggunakan polimer polivinil alkohol hidrogel yang mengandung garam sulfat sebagai elektrolit dan elektroda nanopori karbon dari bahan tempurung kelapa. Polimer hidrogel elektrolit dihasilkan dari proses ikat silang polivinil alkohol yang mengandung garam sulfat dan polimer selulosa (natrasol) dengan menggunakan metoda sol gel. Untuk menghasilkan konfigurasi superkapasitor, polimer hidrogel elektrolit diletakkkan diantara elektroda nanopori karbon yang diinjeksikan garam elektrolit. Adapun nanopori karbon dihasilkan dari proses pemanasan sederhana pada tempurung kelapa yang diaktivasi dengan garam alkali.
Telah dilakukan studi analisis pori pada material nanopori dengan menggunakan metoda pengolahan c... more Telah dilakukan studi analisis pori pada material nanopori dengan menggunakan metoda pengolahan citra. Pengolahan citra dilakukan pada citra SEM dengan memanfaatkan aplikasi toolbox yang terdapat pada perangkat lunak Matlab. Melalui toolbox ini dapat ditentukan besarnya ukuran pori dan porositas yang terdapat pada citra SEM. Didapatkan bahwa distribusi ukuran pori dalam skala mikrometer sampai nanometer. Hasil studi menunjukkan bahwa pengolahan citra cocok untuk diterapkan pada karakterisasi material nanopori.
Berkala Fisika, Apr 1, 2010
Tunneling current in bipolar transistors Si/Si 1-x Ge x /Si anisotropic hetero structure for germ... more Tunneling current in bipolar transistors Si/Si 1-x Ge x /Si anisotropic hetero structure for germanium conditions on a constant basis is not analyzed here. The concentration of germanium in the base which is not constant will result in the potential profile at the base is not flat, but will be graded according to the germanium concentration. Tunneling current calculation is performed semi-analytically and numerically. The calculation result obtained then matched with experimental data. The results show that the results of analytical calculations with results of seminumerical calculations. While analytical calculations with experimental data only flows from the VBE 0.3 to 0.6 V.
Uploads
Papers by Khairurrijal Khairurrijal