Your child’s room, it must be equally functional as well as attractive to a person’s eye simply because they’re going to spend a lot of time in that room. So, you have to choose wisely whenever you pick out the kids bedroom furniture for their bedroom. And, one thing you need to do would be to also include them in for the procedure, otherwise, they may not necessarily believe the room is assigned to them, although baby’s room household furniture could possibly be an exemption.
First off, your kids bedroom furniture that you buy must help your child get organized. So, when you inform them that they must clean their room, that they have furniture set up which will make performing that very easy. The very best methods of doing that are the ones that will make the most sense, just like a dresser with compartments, a nightstand that also has a drawer, and you also may even buy them a bed frame which also has drawers built right into it. If you are planning to include a Television inside your child’s bedroom, then ensure that you purchase an entertainment centre. It will nicely keep things in place since it also provides storage space, in addition, your little one will be able to always locate a game console whether it has one certain place to be placed.
As well as the storage and organization aspect of things, you should also find them furniture that is also practical for other reasons. Like, when your little one has homework, you ought to buy a children’s table so there is a location to get that homework done. That very same desk will even offer you space for storage at the same time simply because they normally come with compartments.
Now that you know what functional kids bedroom furniture you need, it’s time to make certain that you go with choices that go with your child’s personality. This is when their own opinion comes into play. You’ll be able to ask them what they like and find something to fit. So, if they like bright colours, then something which is finished with red and yellow paint could be what you want with components to match. Or, if your child wants something that is a lot more calm, but nevertheless pleasing to look at, then something that features a wood stained finish will be the ideal solution.
Basically, with kids bedroom furniture there are a variety of stylish choices to pick from as well as the ones which were just touched on. A great way for you and your child to look into the many choices instead of spending hours in a furniture store is by browsing on the internet and doing your price comparisons there. It might be a terrific bonding for the two of you so when you both decide on something, it can be delivered right to your home and unpacked right in your kid’s bedroom if you wish. You may have to spend a little extra on white glove shipping, however it is worth every penny.
In the end, if you’d like your kid’s room to be functional and good to view, you will want to acquire children’s bedroom furniture that has both qualities. If you do not, then you certainly might end up having a mess and an unsatisfied child on your hands.
The Influence of Quenching Process on the Corrossion Rate of UZr Alloy Fuel
Masrukan, Kadarjono A
Quenching process was shown to have influence on the corrosion properties of UZr fuel. Alloys with 2, 6, 10, 14 and 55% Zr were prepared using an electric arc furnace. Some of the UZr alloys were quenched while the other were corroded in water vapor at 100 oC for 140 h. Almost all alloys that were not quenched possessed a lower corrosion rate compared to those that were quenched, except for 2% Zr. F alloys that were not quenched, the corrosion rate decreased as the Zr content increased. At 2% Zr, the rate reached 2.94 mg/h, and increased to 0.206 mg/h at 6% Zr. For quenched alloys, the corrosion rate also decreased as the Zr content increased. At 2% Zr, the rate was 2.94 mg/h, and went up to 0.375 mg/h at 6% Zr. Overall, UZr alloys that did not undergo quenching were shown to have better corrosion resistance.
Free terms: quenching, UZr, corrosion rate
Determination of Process Parameters for Preparing Fine Powder of UO2 Fuel according to PHWR Type Fuel Specifications
Latief A
Preparation of UO2 pellets of PHWR type has been performed using several process parameters, i.e. compacting pressure, sintering temperature( heating rate and sintering time) in an argon atmosphere. The objective was to obtain (the optimum parameters)optimum compacting pressure and sintering temperature in order to satisfy the specifications established for UO2 fuel, which include 95% TD, grain diameter of 6 - 8 mm for sintered pellets, and O/U ratio of 2.00 ± 0.015. The work consisted of compating UO2 pellets from fine powder at 2.93 - 5.27 ton/cm2, sintering of UO2 pellets at 1000 - 1200 oC, heating at a fixed rate of 250 °C/h, and sintering for 3 hours. The methods used to determine the optimum parameters were evaluating the density of UO2 pellets obtained at different compacting pressures, the density of sintered UO2 pellets obtained at different compacting pressures and sintering temperatures, calculating grain diameter of sintered UO2 pellets using optical microscopy / SEM, and determining the O/U ratio. It was found that the optimum parameters for fine powder of 38 - 75 mm, which complied with the UO2 fuel specifications, were compacting pressures of 4.10 ton/cm2 and 4.68 ton/cm2, sintering temperature of 1200 °C, a heating rate of 250 °C/h, and sintering time of 3 h.
Free terms: UO2 fuel, PHWR
Coating Rocket Nozzle with Boron Carbide.
Sugondo, Langenati R., Futichah, Mujtahid
Research was conducted to investigate the use of boron carbide for coating rocket nozzle using boron coating technique called powder packing method. The coating temperature was 1000 °C with coating time varied at 6, 8 and 12 h. Observation of the microstructures using optical microscope and SEM indicates that the increase of heating time results in a significant increase of the coating thickness for both ST37 and S45C. The increase of coating
thickness is proportional to the increase of heating time at the given temperature. Meanwhile, hardness (Vickers method) of the boronized materials increased significantly compared to the initial materials. Using heat load simulation by means of flame spray test, sample ST37 that had undergone boronization at 1000 °C for 8 h was able to withstand the heat for 30 min.
Free terms: boronization, steel ST37, steel S45C, rocket nozzle, low carbon steel, powder packed, heating test
The Influence of Voltage, Time and Acidity on Electrodialysis of Uranyl Nitrate Solution
Sigit, Widodo G., Langenati R., Torowati, Yudhi N
Electrodialysis process of uranyl nitrate solution with variation( bagamana kalau variable) of voltage, time and acidity has been investigated in order to study uranium separation from the feed solution. The electrodialysis cell consists of anode, feed and cathode compartments, in which the anode and feed compartments are separated by an anion exchange membrane (AEM), and the cathode and feed compartments by a cation exchange membrane (CEM). During electrodialysis, the uranyl ions were drawn toward the CEM, while the nitrate ions toward the MTA. The uranium concentration in the feed was analyzed using a titroprocessor. Higher voltage and longer duration resulted in less uranium concentration in the feed compartment, whereas higher uranium concentration in the cathode compartment resulted in separation of uranium from the feed toward the cathode compartment. The uranium concentration in the feed decreased to 38.09% at 8 V, or the final U concentration was 0.832 g/L
for electrodialysis time of 180 min and an acidity (nitric acid normality) of 4.58 N. The acidity of the feed also decreased the uranium concentration. At 4 and 5 V, a low acidity of 2 N resulted in a small increase of uranium concentration in the cathode compartment, which continued to increase at 3.56 N before decreasing at 4.58 N.
Free terms: electrodialysis, uranyl nitrate, voltage, acidity (nitric acid normality)
The Effect of O/U Ratio on the Phase Change in Reject Sintered UO2 Pellets after Oxidation Process
Futichah, Langenati R
UO2 powder can be recovered from reject sintered UO2 pellets through oxidation and reduction processes. Oxidation in an air atmosphere at certain temperature will yield a new phase, U3O8. The change of phase signifies the effect of oxidation temperature on the O/U ratio, i.e. the O/U ratio determines the type of phase that is formed. The effect of the O/U ratio on the phase change and lattice parameter of the uranium oxide compound was studied by conducting oxidation at 600 oC for 1, 2, 3, 4, 5 and 6 h. Gravimetry and X-Ray Diffraction method were used respectively to analyze the O/U ratio and crystallography. Correlations between the O/U ratio with time and lattice parameters were obtained. The O/U ratio of the sintered pellets was ~2.66 to 2.68 indicating U3O8 phase has been formed.
Free terms: O/U ratio, UO2 oxidation process, reject sintered pellets, lattice parameter of U3O8
THE THERMODYNAMIC MODELING OF
THE URANIUM-OXYGEN SYSTEM
Basuki A. Pudjanto
Pusbangtek Bahan Bakar Nuklir dan Daur Ulang – BATAN, Serpong
Centre for Development of Nuclear Fuel and Recycling Technology – BATAN, Serpong
ABSTRACT
THE THERMODYNAMIC MODELING OF THE URANIUM-OXYGEN. The thermodynamic modeling of the uranium-oxygen (U-O) system, which is of first importance in the development of a nuclear thermodynamic database, has been performed. The thermodynamic properties of the phases present in the U-O system are described using the compound energy model with ionic constituents for the solids and an ionic two-sublattice model for the liquid. For the uranium dioxide, the structure is described using three sublattices, one for the cations U3+, U4+ and U6+, one for the normal site of oxygen ions, and one for the interstitial oxygen ions. Vacancies are included in both oxygen sublattices. In this first approach, the homogeneity ranges of the U4O9-y and U3O8-y compounds are not represented. Phase diagram and thermodynamic properties, then, have been calculated from the optimized Gibbs energy parameters, assuming that the system is in thermodynamic equilibrium, i.e. by finding the minimum for the total free energy of the system. The thermodynamic calculation is conducted through CALPHAD (Calculation Phase Diagram) approach, with the help from the Thermo-Calc code. The results obtained show that the consistency between the calculated results and the experimental data is quite satisfactory.
FREE TERMS: Nuclear fuel, Uranium oxide, Oxygen potential, Modeling, Thermodynamics
STUDY OF CORROSION RATE OF Zr-Mo-Fe-Cr ALLOY IN SATURATED VAPOUR MEDIUM AT TEMPERATURE 250 - 300°C.
Sungkono
Centre for Development of Nuclear Fuel and Recycling Technology – BATAN, Serpong
ABSTRACT
STUDY OF CORROSION RATE OF Zr-Mo-Fe-Cr ALLOY IN SATURATED VAPOUR MEDIUM AT TEMPERATURE 250 - 300°C. Zr-Mo-Fe-Cr alloy represents one of the candidates for structure material of nuclear fuel element in the future. The alloy has to fulfil certain qualifications which include mechanical, physical, chemical and neutronic properties to serve as nuclear fuel element structure material. The objective of this research is to study the corrosion rate of Zr-Mo-Fe-Cr alloy in saturated vapour medium at temperatures of 250 - 300 °C. The method used in the research is gravimetry. The test results indicate that the corrosion rates of Zr-0.3%Mo-0.5%Fe-0.5%Cr and Zr-0.8%Mo-0.5%Fe-0.5%Cr alloys, which have been homogenized at temperature of 750 °C for 3 hours or at temperature of 850 °C for 3 hours, in saturated vapour medium at temperatures of 250 - 300 °C for 2 - 16 hours, are relatively equal and increase cubically. However, Zr-0.3%Mo-0.5%Fe-0.5%Cr alloy shows relative better corrosion resistance than Zr-0.8%Mo-0.5%Fe-0.5%Cr alloy. The corrosion rates of Zr-Mo-Fe-Cr alloys are influenced by the content of Mo and homogenization treatment on the alloy ingots.
FREE TERMS: Zr-Mo-Fe-Cr alloy, Homogenization, Corrosion rate
STUDY ON SEPARATION OF 137Cs FROM 235U FISSION PROCESS WASTE. Utilization of Silica Gel-Supported Ferrocyanide
Complex Salt FOR 137Cs PICKING
Sunarhadijoso Soenarjo, Anung Pujianto
Centre for Radioisotopes and Radiopharmaceuticals – BATAN, Serpong
ABSTRACT
STUDY ON SEPARATION OF 137Cs FROM 235U FISSION PROCESS WASTE. Utilization of Silica Gel-Supported Ferrocyanide Complex Salt for 137Cs PICKING. In connection with the potential domestic demand especially in the fields of industry and nuclear medicine, the separation of 137Cs from 235U fission process waste is to be of interest although its economic value could be a polemic. A preliminary study on the separation of 137Cs from the 235U fission process waste generated in the production of 99Mo in P.T. BATAN Teknologi, Serpong, was performed through experiments on 137Cs picking from sample solution of the radioactive fission waste (RFW). The presented study is aimed to gain experimental data supporting utilization of the matrix of silica gel-supported ferrocyanide complex salt for the separation of 137Cs from RFW. Subsequent step would be the recovery and purification of 137Cs as part of production technology of 137Cs. The RFW sample was batch-treated with the matrix of silica gel-supported ferrocyanide complex salt which was synthesized from silica gel, potassium hexacyanoferrate(II) and copper(II) chloride. The binding of radioisotopes in RFW on the matrix was observed by g-spectrometry of the RFW solution before and during the treatment. The results showed that approximately 85% of 137Cs could be picked from the RFW sample into the matrix. Less amount of 95Zr and 95Nb was bound into the matrix. 103Ru was slightly bound into the matrix whereas 141/144Ce and 129mTe were not. It was observed that by using 0.2 and 0.4 g of matrix for 10 ml of RFW, the amount of matrix influenced the binding quantity of 95Zr and 95Nb but not that of 137Cs.
FREE TERMS: Separation of 137Cs, 235U fission process, Ferrocyanide complex salt, Radioactive fission waste (RFW), g-spectrometry
BORON CARBIDE FOR COATING ROCKET NOZZLE
Sugondo
ABSTRAK
Research has been conducted to investigate the use of boron carbide for coating rocket nozzle, with the objective to coat rocket nozzle by using boron coating technique or boronization. The method of coating being used is the power packing method with two process parameters, which are a temperature of 1000°C and coating time of 6, 8 and 12 hours. Observation of the coating morphology was subsequently performed using optical microscope and SEM to obtain data on the microstructure, thickness and penetration of boron into the material being coated. Next mechanical testing was performed, which is hardness testing using Vickers method. To determine the resistance to heat, testing was performed through simulation method of heat load received by nozzle by means of flame spray test. Results for coating at temperature of 1000°C with heating time of 6, 8 and 12 hours have been obtained. Observation of the microstructures indicates that the increase of heating time results in a significant increase of the coating thickness for both ST37 and S45C. The increase of coating thickness is proportional to the increase of heating time at the given temperature. Meanwhile, the hardness of the boronized materials increases significantly compared to the initial materials. For heating test on sample ST37 that underwent boronization at 1000 °C for 8 hours, the resistance toward heat lasted up to 30 minutes.
Keywords: boronization, steel ST37, steel S45C, rocket nozzle, low carbon steel, powder packing, heating test
