Purwanto A.,Sebelas Maret University |
Widiyandari H.,Diponegoro University |
Jumari A.,Sebelas Maret University
Thin Solid Films | Year: 2012
A high-performance fluorine-doped tin oxide (FTO) film was fabricated by flame-assisted spray deposition method. By varying the NH 4F doping concentration, the optimal concentration was established as 8 at.%. X-ray diffractograms confirmed that the as-grown FTO film was tetragonal SnO 2. In addition, the FTO film was comprised of nano-sized grains ranging from 40 to 50 nm. The heat-treated FTO film exhibited a sheet resistance of 21.8 Ω/ with an average transmittance of 81.9% in the visible region (λ = 400-800 nm). The figures of merit shows that the prepared FTO film can be used for highly efficient dye-sensitized solar cells electrodes. © 2011 Elsevier B.V. All rights reserved.
Firdaus M.,Sebelas Maret University
Chemistry | Year: 2016
An alternative on the determination of activation energy in nonisothermal chemical kinetics is described.
Roswitha M.,Sebelas Maret University |
Baskoro E.T.,Bandung Institute of Technology
AIP Conference Proceedings | Year: 2012
For a graph G(V,E), an edge-covering of G is a family of different subgraphs H 1,..H k such that any edge of E belongs to at least one of the subgraphs H i, 1 ≤ i ≤ k. If every H i is isomorphic to a given graph H, then G admits an H-covering. Graph G is said to be H-magic if G has an H-covering and there is a total labeling f:V∪E→1,2,..V+E such that for each subgraph H′ = (V′,E′) of G isomorphic to H,ΣνV′f(ν) +ΣeE′f(e) is fixed constant. Furthermore, if f(V)=1,2,..V then G is called H-supermagic. The sum of all vertex and edge labels on H, under a labeling f, is denoted by Σf(H). In this paper we study H-supermagic labeling for some classes of trees such as a double star, a caterpillar, a firecracker and a banana tree. © 2012 American Institute of Physics.
Setyawan A.,Sebelas Maret University
Procedia Engineering | Year: 2013
Semi-flexible pavements are manufactured by producing a very open porous asphalt skeleton and filling the voids with selected cementitious grouts. The resultant composites, referred to as "grouted macadams", combine the flexibility of the bituminous component with the strength and rigidity of the cementitious component. Grouted macadams thus combine the best qualities of concrete and asphalt pavements, namely the flexibility and freedom from joints that characterize asphalt and the high static bearing capacity and wear resistance of concrete. The properties of the grouted macadam composites were assessed using a range of engineering, compressive strength is the most common strength test for rigid pavements since it is relatively easy to conduct compared to other tests and numerous correlations exist to predict other material properties based on compressive strength values Since semi-flexible pavements possess mechanical properties in between bituminous mixtures and concrete, the compressive properties of the grouted macadams designed in this study have been investigated. The unique correlations between each component, namely asphalt skeleton, grout, aggregate type and size were established also the comparison to the other type of investigations and conventional concrete. © 2013 The Authors.
Purwanto A.,Sebelas Maret University
Advanced Materials Research | Year: 2014
Fluorinated tin oxide (FTO) is well known transparent conductive oxide which is widely applied for optoelectronic applications. Commercially, high-performance (FTO) film was fabricated by sputtering method or other low pressure methods. The product of these methods is expensive due to the high price of capital cost for the apparatus. To cut the price of FTO, atmospheric condition methods were developed and actively investigated using a simple device. By controlling the process conditions; such as processing temperature, precursor concentration, doping concentration, and reactor configuration; high performance FTO glass was successfully produced. The sheet resistance of the prepared FTO glass can be controlled from 9.55 - 63 Ω/□. In addition, its transparency is approximately 77% which is ideal characteristics for the dye sensitized solar cell (DSSC) electrode application. © (2014) Trans Tech Publications, Switzerland.
Cari C.,Sebelas Maret University |
Suparmi A.,Sebelas Maret University
Journal of Physics: Conference Series | Year: 2013
The energy eigenvalues and eigenfunctions of Schrodinger equation for three dimensional harmonic oscillator potential plus Rosen-Morse non-central potential are investigated using NU method and Romanovski polynomial. The bound state energy eigenvalues are given in a closed form and corresponding radial wave functions are expressed in associated Laguerre polynomials while angular eigen functions are given in terms of Romanovski polynomials. The Rosen-Morse potential is considered to be a perturbation factor to the three dimensional harmonic oscillator potential that causes the increase of radial wave function amplitude and decrease of angular momentum length. Keywords: Schrodinger Equation, Three dimensional Harmonic Oscillator potential, Rosen-morse non-central potential, NU method, Romanovski Polynomials © IOP Publishing Ltd 2013.
Patiha M.F.,Sebelas Maret University
Chemistry | Year: 2016
So far, the kinetic approach for determination of the rate constants of reversible reaction is still using the equilibrium concentration. Basically, this is thermodynamic concept. This technique is not only needs a long time for the experiments but also gives only the exact value of the forward rate constant. The exact value of backward rate constant must be determined based on the postulated reaction mechanism. This study presents a simple technique on the determination of the exact value of both forward and backward rate constants using irreversible approach on three data at the early stages of a reaction and then used for the determination of equilibrium constant. This theoretical study is supported with statistical analysis on the experimental data adapted from the literatures. The results showed that the technique is valid and reliable.
Purwanto B.,Sebelas Maret University
Acta medica Indonesiana | Year: 2012
to determine the effect of oral N-acetylcysteine (NAC) on plasma levels of inflammatory markers in Continuous Ambulatory Peritoneal Dialysis (CAPD) patients. we performed a placebo-controlled study over 8 weeks in 32 patients on regular CAPD. The patients were divided into 2 groups of 16 patients matched for age and gender. The first group was given NAC 2x600 mg/day for 8 weeks and inflammatory parameter was compared with control group. The immune system is determined from the average levels of Procalcitonin, IL-6, IL-1, C3, SICAM, hsCRP, and TNF- before and after treatment with NAC. Student t-test was performed to compare the means between NAC receiving and control groups. All statistics were done using SPSS software (SPSS Ver 16.0). administration of NAC, significantly diminished PCT (-0.38±0.57 vs 0.09±0.14; p=0.004), IL-6 (-1.94±3.03 vs 1.19±1.99; p=0.002), IL-1 (-0.14±0.21 vs 0.01±0.04; p=0.010), C3 (-7.40±12.04 vs 4.60±8.12; p=0.002), sICAM (-80.59±29.18 vs -35.02±46.99; p=0.007), hsCRP (-1.50±1.32 vs 0.81±1.17; p<0.001) and TNF- (-0.73±0.47 vs 0.14±0.74; p<0.001) levels compared control to group. short-term oral NAC treatment resulted in reduction of circulating PCT, IL-6, IL-1, C3, sICAM, hsCRP, and TNF- in CAPD patients.
Saraswati T.E.,University of Shizuoka |
Saraswati T.E.,Sebelas Maret University |
Ogino A.,University of Shizuoka |
Nagatsu M.,University of Shizuoka
Carbon | Year: 2012
We describe the amino group surface functionalisation of graphite-encapsulated iron compound nanoparticles by radio frequency (RF) plasma processing followed by oxidized dextran immobilization. We have found that surface treatment using plasma represents an important step before biomolecules immobilization. After plasma treatment, the dispersion property of nanoparticles in dextran solution in water was significantly improved. The successful dextran immobilization was confirmed by X-ray photoelectron spectroscopy (XPS) and high resolution-transmission electron microscopy (HR-TEM) analyses followed by amino group derivatization using 4-(trifluoromethyl)-benzaldehyde (TFBA). As an evidence for covalent bonding between nanoparticles and dextran, the area percentage of deconvoluted CN peak at ∼389.6 eV increased from 0% to 10.53 ± 1.30% with increasing the dextran concentration. The result is consistent with the evidenced decreasing of the free amino group percentage from 68.09 ± 5.10% to 14.73 ± 5.89% on the nanoparticle surface after dextran immobilization. © 2011 Elsevier Ltd. All rights reserved.
Purwanto A.,Sebelas Maret University
AIP Conference Proceedings | Year: 2014
Flame assisted spray pyrolysis (FASP) is a class of synthesis method for nanomaterials fabrication. The ability to control nanomaterials characteristics and easy to be-scaled up are the main features of FASP. The crystallinity and particles size of the prepared nanomaterials can be easily controlled by variation of fuel flow rate. The precursor concentration, carrier gas flow rate, and carrier gas can be also used to control the prepared nanomaterials. Energy related nanomaterials preparation uses as the example case in FASP application. These material are yttrium aluminum garnet (YAG:Ce) and tungsten oxide (WO 3). It needs strategies to produce these materials into nano-sized order. YAG:Ce nanoparticles only can be synthesized by FASP using the urea addition. The decomposition of urea under high temperature of flame promotes the breakage of YAG:Ce particles into nanoparticles. In the preparation of WO 3, the high temperature flame can be used to gasify WO3 solid material. As a result, WO3 nanoparticles can be prepared easily. Generally, to produce nanoparticles via FASP method, the boiling point of the material is important to determine the strategy which will be used. © 2014 AIP Publishing LLC.