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Stone columns are used in practice for ground improvement of soft subsoil. Current design procedures of these columns are based on simple empirical calculations. This research project investigates the behavior of a base reinforced embankment constructed on a soft clay layer, which is improved with stone columns. Centrifuge tests were performed in order to gain a deeper understanding of the interaction problem within the structure. Stone columns were constructed in-flight using a newly developed installation tool. First analysis of test data shows a significant change in stress state due to column construction and the influence on the clay behavior.

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Nowadays natural disasters phenomena as hurricanes, volcanic eruptions, tsunamis or earthquakes, are still difficult to prevent. Based on signaling of the phenomenon imminent appearance in the destructive area, important limitations in human losses and material damages will be carried out. For that  reason, WARNING turned into a key objective, both in theoretical and practical research.  For the earthquakes, warning intervals are nevertheless very short - seconds to maximum one minute (Mexico City case). Even if the time window is reduced, automated decision measures are possible to establish in case of an well organized system, mainly for: protection of dangerous chemical units and oil installations; shutdown valves of the natural gas pipelines to prevent fire hazard; protection of nuclear power plants and other high-risk nuclear objectives; electrical insulating of the power distribution network systems; alerting of emergency services, alerting of civil protection, and particularly of  civil population; protection of railway transportation systems etc.  In Romania, the major seismic risk zone is located in Vrancea region. The earthquakes occurring in this area are the main sources of the seismic hazard on the Romania territory.  Seismotectonic characteristics of the Vrancea region offered the opportunity to create and develop a rapid seismic warning system. This system is simple, reasonably low-priced and robust and allows warning in an approximately 25 seconds time window for Bucharest. Warning signal obtained will be issued at the responsible factors and specific users in order to control automated blocking of the installations and to carry out the required protection actions.

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Abstract

The essay describes two copies of documents from the hand of Staatskanzler Wenzel Anton Kaunitz-Rietberg sent to the Swiss engraver and art dealer Christian von Mechel. The letters were written at the time when Mechel was involved with the installation of paintings from the Imperial collection in the Belvedere palace, Vienna. The first letter is dated June 14th, 1779, and tells of several paintings that Mechel had suggested the Austrian court; one being identified as “Decent from the Cross” by Sandrart, which was included in Mechel's Belvedere hanging, and is now to be found in Cluj/Klausenburg. The document also refers to four paintings by Teniers in Nymphenburg offered by Kurfürst Karl Theodore von Pfalz-Sulzbach, (from 1777 onwards also Kurfürst von Bayern), who had retained Mechel as his agent in this affair. These four works, showing the interior of Archduke Leopold Wilhelm's paintings gallery, could very well be the set of paintings now in the Bayrische Gemäldesammlung in Munich. This would suggest that the transfer to the Austrian court must have failed to happen for reasons not yet known. The second letter is dated July 28th, 1790 and reveals an increasing of impatience towards Mechel, who Kaunitz implys is causing delays in the completion of the gallery installation. Kaunitz further makes reference to a large painting by Frans Floris, which could correspond to “The Last Judgement” (ill. 4).

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This paper focuses on Vasily Shukshin’s “working records” dated from 1966. It is established that a lot of contexts and names are important for the interpretation of these records: from the antique myths to Russian literature. In the paper, it is proved that the motive of the waterway of a ship appears in Shukshin’s texts as the concentrated symbol of spiritual aspirations, warm rushes, as the allegory of movement towards the aim and the overcoming of obstacles. At the same time, it is also a symbol of moral ascension, which is shown by the reflections about intelligence as the aim of the artist. The conclusion drawn is that the poetics of Vasily Shukshin’s texts represents a very open and dialogical structure with wide referential installations.

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In the environment in which we live we are exposed to different kinds of radiation. Radiation is divided into ionising radiation as a result of radioactive decay and into non-ionising radiation, which is the consequence of electromagnetic waves. The use of electric power has penetrated every area of human activities. Its accompanying effects are electromagnetic waves, which expand into the space surrounding the installations for the generation, transmission and use of electric power. The research in the last 20 years has concentrated on the possibly harmful effects of low frequency (0–300 Hz) electromagnetic waves on man and the environment. However, not much research has been conducted into the magnetic fields under the electric overhead traction systems. Therefore, this paper is presenting the results of the calculation of the magnetic field under the electric overhead traction system on Slovenian railways.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: U. Sansone, Chang Kim, G. Kis-Benedek, R. Schorn, E. Zeiller, A. Qaribov, V. Huseynov and A. Chupov

Abstract  

In the frame of an International Atomic Energy Agency Technical Cooperation project, a radiological survey was performed in the Araks and Kura Rivers (Azerbaijan). Sediment samples, and where available, aquatic plants were collected along these two rivers and their inflow and tributary rivers. 137Cs, 238U, 234U, 239+240Pu, 238Pu, 90Sr and 241Am activity concentrations were measured. The radionuclide levels measured were relatively low, and in most cases below the detection limit, as compared with those from other areas of the world which have been directly affected by effluents from nuclear installations or influenced by the Chernobyl accident. The results indicated that the radionuclides are of natural origin or attributable to the atmospheric fallout from nuclear weapons tests or to the Chernobyl-derived deposition.

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Abstract  

Individual monitoring of radiation workers handling Pu in various nuclear installations requires the detection of trace levels of plutonium in bioassay samples. It is necessary to develop methods that can detect urinary excretion of Pu in fraction of mBq range. Therefore, a sensitive method such as fission track analysis has been developed for the measurement of trace levels of Pu in bioassay samples. In this technique, chemically separated plutonium from the sample and a Pu standard were electrodeposited on planchettes and covered with Lexan solid state nuclear track detector (SSNTD) and irradiated with thermal neutrons in APSARA reactor of Bhabha Atomic Research Centre, India. The fission track densities in the Lexan films of the sample and the standard were used to calculate the amount of Pu in the sample. The minimum amount of Pu that can be analyzed by this method using doubly distilled electronic grade (E. G.) reagents is about 12 μBq/L.

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Abstract  

The continued erection of nuclear installations which is expected in the future involves a greater production of long-lived fission products, which result in a concentration increase in the biosphere, the hydrosphere and the atmosphere. In the frame of a broad survey program, a routine method has been developed with the help of the European Communities to investigate the129I content of thyroid glands of cows. It is the purpose of this project to determine the present concentration situation of this nuclide, which in the Federal Republic of Germany mainly concerns the North German low plains. Between autumn '76 and summer '77 18 cows have been investigated with respect to129I, and thyroid glands have been taken at different times in November '76 and August '77. Without exception, the animals were 13-month old bulls, part of which has pastured, while the other part has been fed. The detection limit of the method is 20fCi of129I.

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Abstract  

The fuel claddings in the Pressurised Water Reactor are corroded in water at high temperature and high pressure. The technical device ableto follow continuously the corrosion rate in conditions close to this medium does not yet exist. That is the reason why a high pressure thermogravimetric installation based on magnetic suspension has been designed to study in situ the oxidation kinetics of the zirconium based alloys under water vapour until 50 bars of pressure at 415°C. The accuracy of measurements is about 5·10−5 g under 2 bars, and 10−4 g under 50 bars. The reproducibility of measurements was verified and the deviation regarding post test weighing at room temperature is around 5·10−5 g what is clearly satisfying. Finally, the results presented in this work allow validating the high pressure thermogravimetric measurements obtained with this magnetic suspension device.

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Abstract  

The results of activation studies of concrete ingredients for shielding structures of nuclear installations in the aspect of their decommissioning are given. It is shown that for the long-lived induced radioactivity of construction mineral materials irradiated for 30 years and cooled for more than one year such radionuclides as calcium, iron, cobalt, caesium and europium are responsible. Elemental content of the binding agent and raw material components for their production is obtained by neutron activation analysis. The results show that the type of the binding agent influences to a great extent the concrete shielding activity. The concentration of the above mentioned elements should be taken into account even at the stage of nuclear power plants design. It would allow one to make a prognosis on the volume and radioactivity of wastes as on the radioactivity effect felt by the staff engaged in the decommissioning.

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