Atom Indonesia (E-Journal)
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Induced Mutation on Jatropha (Jatropha Curcas L.) for Improvement of Agronomic Characters Variability
Get PDFInduced mutation can be used for improving quality in term of seed production, oil content in seed and early maturity of Jatropha with the aim for bio_diesel in Indonesia. The doses of 10, 15,20, and 25 Gy of gamma applied to cuttings was able to increase genetic variability in vegetatively propagated plants of Jatropha at M1V1 (mutant-vegetative-1) generation. Selection for desirable trait will be done at M1 V2 (mutant-1 and vegetative-2) generation untill homogenous plants obtained. Gamma rays at dose of 20 to 25 Gy damaged several genes controlling growth and development on Jatropha which was shown by dwarf and poor plant growth compared to control (plant without irradiation). Irradiation with the dose of 10 Gy raised genetic variability on plant development which was identified with early maturity, 100 seeds weight was 30% over control, and the number of branch growth was goo
Crystallite Size and Microstrain Measurement of Cathode Material after Mechanical Milling using Neutron Diffraction Technique
Get PDFThe measurements of neutron diffraction patterns of commercially product and 10 hour mechanically milled cathode material lithium cobaltites (LiCoO2) have been performed. Rietveld analysis using FullProf does not show the change of crystal structure due to milling process, but the diffraction pattern has a lower intensity and the diffraction-line was broadening. The results of line-broadening study on milled sample using Rietveld methods detected that the microstrain was occurred in the sample with value 0.127080(35) % and the average crystallite size was 424.78(20) Å.Received: 7 October 2010; Revised: 31 October 2010; Accepted: 1 November 201
Radiation-Induced Degradation of Pirimiphos Methyl in Aerated Solution
Get PDFDegradation of pirimiphos methyl (1) as an active ingredient in Minawet insecticide 250 EC formulation in aqueous solution was studied. The absorbance, pH, COD (Chemical Oxygen Demand) in aerated solution, and the analyses of degradation products at various irradiation doses with dose rate of 5 kGy/h were observed. The absorbance decreased rapidly at low doses (£ 10 kGy), while at high doses ( 10 kGy) decreased slowly. The optimum irradiation dose for pirimiphos methyl degradation in aerated solution was found to be 15 kGy at pH 3.6. At that condition, more than 99% of pirimiphos methyl has been degraded and the COD of solution decreased about 82%. The analysis of irradiated samples by GC-MS and HPLC showed that 2-diethylamino-6-methyl-4-oxo-3,4-dihydropyrimidine (3) and oxalic acid were clarified as degraded product
Nuclear Magnetic Resonance Imaging of Li-ion Battery
Get PDFNuclear magnetic resonance (NMR) imaging has high sensitivity to proton (1H) and lithium (7Li). It is a useful measurement for electrolyte in Li-ion battery. 1H NMR images of lithium ion battery which is composed of LiMn2O4 / LiClO4 + propylene carbonate (PC) / Li-metal have been studied. 1H NMR images of electrolyte near cathode material (LiMn2O4) showed anomalous intensity distribution, which was quite inhomogeneous. From NMR images as a function of repetition time (TR), it was concluded that the anomalous intensity distribution was not due to change of relaxation time but an indirect (spatial) para-magnetization effect from cathode material. The paramagnetization induced by high magnetic field distorts linearity of magnetic gradient field, leading to apparent intensity variance. This functional image is an easy diagnostic measurement for magnetization of cathode material, which allows the possibility to check uniformity of cathode material and change of magnetization under electrochemical process. Received: 7 October 2010; Revised: 1 December 2010; Accepted: 17 December 201
The Effect of Toluene Solution on the Hydrogen Absorption of the Mg-Ti Alloy Prepared by Synthetic Alloying
Get PDFThe synthesis and characterization of the Mg–Ti alloy have been carried out through a mechanical alloying technique under toluene solution. The Mg and Ti powders are milled for 10, 20, and 30 h in a high energy ball mill. The milled alloys are then hydrided at a temperature of 300 oC in order to investigate the possibility used for hydrogen storage materials. The refinement analyses of the x-ray diffraction patterns show that mechanical alloying of the Mg–Ti powders under toluene solution results in the formation of the TiH2 and Mg2Ti phases. Quantitative analyses indicate that the mass fractions of the TiH2 and Mg2Ti phases are 62.90 % and 30.60 %, while the value for Mg and Ti amount to 2.6 wt% and 1.25 wt%. On hydriding at a temperature of 300 oC, the milled powders are transformed into Mg2TiH4, TiH2 and γ-MgH2 phases with the mass fractions of 25.48 wt%, 64.0 wt%, and 10.52 wt%, respectively. Microstructure analyses show that before milling the shape of particle is mostly a ball shape, after 30 h of milling the shape of particles changes into polygonal shape, and upon hydriding the shape of particles changes from a polygonal shape into an irregular one. The final composition of the specimen after hydriding exhibits that Mg-Ti alloy can be promoted as a hydrogen storage material.Received: 27 January 2009; Revised: 19 November 2009; Accepted: 24 November 200
Electrical Properties of Photodiode Ba0.25Sr0.75TiO3 (BST) Thin Film Doped with Ferric Oxide on p-type Si (100) Substrate using Chemical Solution Deposition Method
Get PDFIn this paper we have grown pure Ba0.25Sr0.75TiO3 (BST) and BST doped by Ferric Oxide Fe2O3 (BFST) with doping variations of 5%, 10%, and 15% above type-p Silicon (100) substrate using the chemical solution deposition (CSD) method with spin coating technique at rotation speed of 3000 rpm, for 30 seconds. BST thin film are made with a concentration of 1 M 2-methoxyethanol and annealing temperature of 850oC for the Si (100) substrate. Characterization of the thin film is performed for the electrical properties such as the current-voltage (I-V) curve using Keithley model 2400 as well as dielectric constant, time constant, pyroelectric characteristics, and depth measurement. The results show that the thin film depth increases if the concentration of the Ferric Oxide doping increases. The I-V characterization shows that the BST and BFST thin film has photodiode properties. The dielectric constant increases with the addition of doping. The maximum dielectric constant value is obtained for 15 % doping concentration namely 83.1 for pure BST and 6.89, 11.1, 41.63 and 83.1, respectively for the Ferric Oxide doping based BST with concentration of 5%, 10%, and 15%. XRD spectra of 15% of ferric oxide doped BST thin film tetragonal phase, we carried out the lattice constant were a = b = 4.203 Å; c = 4.214 Å; c/a ratio = 1.003. Received: 01 February 2010; Revised: 04 October 2011; Accepted: 02 November 201
Measurements of Residual Stresses in Cold-Rolled 304 Stainless Steel Plates Using X-Ray Diffraction with Rietveld Refinement Method
Get PDFThe determination of the residual stresses using X-ray powder diffraction in a series of cold-rolled 304 stainless steel plates, deforming 0, 34, 84, 152, 158, 175 and 196 % reduction in thickness has been carried out. The diffraction data were analyzed using the Rietveld structure refinement method. The analysis shows that for all specimens, the martensite particles are closely in compression and the austenite matrix is in tension. Both the martensite and austenite, for a sample reducing 34% in thickness (containing of about 1% martensite phase) the average lattice strains are anisotropic and decrease approximately exponential with an increase in the corresponding percent reduction (essentially phase content). It is shown that this feature can be qualitatively understood by taking into consideration the thermal expansion mismatch between the martensite and austenite grains. Also, for all cold-rolled stainless steel specimens, the diffraction peaks are broader than the unrolled one (instrumental resolution), indicating that the strains in these specimens are inhomogeneous. From an analysis of the refined peak shape parameters, the average root-mean square strain, which describes the distribution of the inhomogeneous strain field, was predicted. The average residual stresses in cold-rolled 304 stainless steel plates showed a combination effect of hydrostatic stresses of the martensite particles and the austenite matrix.Received: 14 March 2008; Revised: 13 October 2008; Accepted: 6 November 200
Influence of Substrate Temperature on Structural, Electrical and Optical Properties of ZnO:Al Thin Films
Get PDFTransparent and conductive aluminium-doped zinc oxide thin films have been prepared by dc magnetron sputtering technique using targets composed of ZnO and aluminium. Polycrystalline ZnO:Al films were deposited onto a heated glass substrate. Surface morphology and crystalline structure as well as optical and electrical properties of the deposited films were found to depend directly on substrate temperature. From optical and electrical analysis it was observed that optical transmittance and conductivity of the ZnO:Al transparent conductive oxide films increased when the deposition temperature was raised from 200 to 400 oC. Films grown on substrates heated at 300 oC showed a high conductivity value of 0.2 x 102 Ω-1cm-1 and a visible transmission of about 80%. The growth of ZnO:Al thin films on the surface of glass substrate at temperatures of 300 oC and aluminium doping levels of 0.9 at.% were the best to attain ZnO:Al films with optical and structural qualities as required for solar cell applications, as a window material in antireflection coatings or optical filters.Received: 17 March 2009; Revised: 22 November 2009 ; Accepted: 23 November 200
Experimental Study of Quenching Process During Bottom Reflooding Using “Queen” Test Section
Get PDFPhenomenon of quenching of hot fuels in core during bottom reflooding following loca event is investigated in order to understand the performance cooling process. the study is conducted experimentally using queen test section which allow study of rod surface temperature histories based on which the heat fluxes are estimated. the visual observation is also done to study the boiling regimes. the test variables are initial rod temperature, i.e. 400oc, 500oc and 600oc, and coolant flow rate, i.e. 0,01kg/s, 0.02 kg/s and 0.04 kg/s with constant water inlet temperature of 30oc. the results shows different heat transfer regimes such as film boiling, transition boiling, nucleate boiling and convective single phase heat transfer regimes. for specified initial rod temperature, the higher flow rate provides high rewet velocity and higher maximum heat flux, then quenching process is more effective
Experimental Study on the Effect of Initial Temperature on CHF in a Vertical Annulus Narrow Channel with Bilateral Heated
Get PDFStudy on understanding of the complexities of boiling in the narrow channel which was occured in a severe accident on nuclear power plant has been carried out in experimentally using simulation apparatus in order to achieve the safety management capability. Critical Heat Flux (CHF) is one important parameter to control heat during transient accident. The methodology of research is an experiment using experiment apparatus called HeaTiNG-01 test section with modifications in the outside pipe using stainless steel material as the reactor vessel wall simulation. Experiments were conducted by heating the heated rod as a simulation of debris until the desired initial temperature by bilateral heated. Then water with a saturation temperature in atmospheric was poured gravitationally into the narrow channel. Data acquisition system recorded temperature changes in transient during the cooling process. The transient temperature profile in double heating surface and rewetting point (rewet fronts) was characterized. Experiment was conducted at three initial temperature variations i.e. 650oC, 750oC and 850oC and using channel width 1 mm. Experiment data was used to calculate heat flux then to fitting CHF form boiling curve. The results showed that CHF in outer pipe is higher than heated rod, these conditions explain that more heat is released through the outer pipe, so that the heat control can be done from outside the system to reduce the temperature quickly. The average value of CHF for each vertical position 100 mm and 400 mm at outer pipe are 380 kW/m2 and 733 kW/m2, and then at the heated rod are 250 kW/m2 and 497 kW/m2. Received: 20 November 2010; Revised: 25 July 2011; Accepted: 08 August 201