A novel approach for the production of nitrogen doped TiO2 nanoparticles

In this study a visible light active nitrogen doped nanostructure titanium dioxide was synthesized by a simple mixing of Degussa P25 and Urea powder and further thermal treatment under the adequate conditions. Photocatalytic activity of produced nanoparticles was verified by providing of photocatalytic degradation of phenol aqueous solution. Mainly this work was focused on the investigation of the following effects: urea concentration, temperature treatment, catalyst loading and initial phenol concentration. Kinetics study was also carried out. The approach appears to be successful and may be applied for example during the photocatalytic treatment of wastewater streams without or with a limited aid of UV lamps. Copyright © 2015, AIDIC Servizi S.r.l

Integrated Road Safety Approach Towards Safer Road in Indonesia

Safer road is a global issue in the world. Regarding road conditions, traffic conditions, and accident rate in developing countries, including Indonesia, safer road is crucial. Furthermore, the problem is worse because of a number of reasons i.e. data of road geometric, road pavement surface, road furniture conditions, and traffic accident are not well recorded, difference available recorded data among institutions, and beginning level of intelligent transportation systems implementation. Moreover, to reach safer road, all stakeholders involved (road authorities, industries, experts, road users) should work together. In order to reach integrated road safety approach, the aims of this study are to determine steps to decrease number and severity of traffic accident before, during, and after accident occur, and then to recommend road safety scheme towards safer road in Indonesia. Sustainable and consistent implementation of steps and road safety scheme leads to significant improvement of safer road in Indonesia. Keywords: safer road, accident rate, traffic accident, traffic condition Jalan berkeselamatan merupakan isu global di dunia. Terkait dengan kondisi jalan, kondisi lalu lintas, dan tingkat kecelakaan di negara-negara berkembang, termasuk di Indonesia, jalan yang lebih aman sangat penting. Selain itu permasalahan lebih diperburuk oleh beberapa alasan, yaitu data geometrik jalan, kondisi permukaan perkerasan jalan, kondisi perlengkapan jalan, data kecelakaan lalulintas yang tidak tercatat dengan baik, perbedaan data yang tercatat di institusi-institusi terkait, dan implementasi sistem transportasi cerdas baru pada tahap awal. Untuk mencapai jalan yang berkeselamatan semua pemangku kepentingan yang terlibat (otoritas jalan, industri, ahli, pengguna jalan) harus bekerja sama. Dengan memperhatikan pendekatan keselamatan jalan terpadu, tujuan penelitian ini adalah menentukan langkah-langkah untuk mengurangi jumlah dan tingkat keparahan kecelakaan sebelum, selama, dan setelah kecelakaan terjadi serta merekomendasikan skema keselamatan jalan menuju jalan yang lebih aman di Indonesia. Keberkelanjutan dan penerapan yang konsisten langkah-langkah dan skema keselamatan jalan akan menghasilkan perbaikan yang signifikan akan jalan berkeselamatan di Indonesia. Kata

2D approach for modelling self-potential anomalies. Application to synthetic and real data

The aim of this work is to present a 2-D Matlab code based on the finite element method for providing numerical modelling of both groundwater flow and self-potential signals. The distribution of the self-potential is obtained by starting with the solution of the groundwater flow, then computing the source current density, and finally calculating the electrical potential. The reliability of the algorithm is tested with synthetic case studies in order to simulate both the electric field resulting from the existence of a leak in the dam and SP signals associated with a pumping test in an unconfined aquifer. In addition, the algorithm was applied to field data for the localization of piping sinkholes. The results show that the outputs of the algorithm yielded satisfactory solutions, which are in good agreement with those of previous studies and field investigations. In details, the synthetic data and SP anomalies calculated by using the code are very close in terms of sign and magnitude, while real data tests clearly indicated that the computed SP signals were found to be consistent with the measured values

New Approach In Modifying Quenching Processes Based On Possibility Of Controlling Steel's Surface Temperature By Insulating Layer

In the paper is shown a possibility to govern surface temperature of steel parts during quenching by controlling the thickness of the insulating layer. That results in developing the new quenching technologies like austempering process via cold liquids. The investigations were performed with a low concentration of the polyethylene in cold water using 20 mm cylindrical probe instrumented with two thermocouples. It is established that with the increase concentration of polyoxyethylene in cold water (beginning from 0.001 %) different heat transfer modes are observed resulting in the elimination of film boiling process at 0.001 % concentration, increasing surface temperature of probe during self – regulated thermal process, periodical changing of heat flux densities, slow cooling of surface temperature like in oil when concentration reaches 1 % polyoxyethylene in water, and so on. It is underlined that low concentration of polyoxyethylene in water can serve as an excellent quenchant for accelerated and uniform cooling of steel parts decreasing by this way the cost of a coolant. In this case accelerated cooling should be interrupted at proper time to provide optimal hardened layer afterr quenching. Such approach guarantees increasing service life of steel parts after accelerated cooling with the significant decrease of their cost and eliminates carburization process, The technology can be used for hardening large steel parts like large wind mill gears, large bearing rings, etc