[en] The different losses processes affecting a neutral beam since is born into the ions source until is coming into the fusion machine, are dependent of the residual gas pressure distribution inside injector. The OPTIMUS code analyzes that losses and calculates the pressure distribution inside one injector with specific geometry. The adaptation of injector to TJ-II has not required important design changes, only the operating range of the gas flow and the pumping speed have modified. The calculations show that the required gas flows for the optimal operation of the system ned an independent pumping system for the calorimeter box with a pumping speed of 1200001/s. The system efficiency is not affected by an hypothetical beaming effect and it is found also that with a proper conditioning of the injector walls, so that the absorption coefficients do not surpass excessively the unity value, the injector operation remains optimal. (Author) 8 refs

[en] We discuss experimental aspects related to the possible existence of anomalous ZZV couplings (V=Z, γ) in the e⁺ e^-→ZZ process. We find that, among several options, the optimal procedure to quantify their presence requires the inclusion of anomalous coupling in a complete four-fermion final-state generator. Various comparisons and checks proof the correctness of our calculations at the percent level. (Author) 9 refs

[en] A method for the determination of low-level ''226 Ra in environmental and geological samples by alpha spectrometry is described. The method is based on the use of ''225 Ra from ''229 Th as yield tracer and has been developed to analyze U, Th and Ra in the same sample. (Author) 12 refs

[en] TJ-II plasma start-up and heating are made by electron cyclotron resonance waves at the second harmonic of the electron cyclotron frequency. The microwave power of the gyrotrons is transmitted by two quasi-optical transmission lines. The first line launches the microwave power under fixed injection geometry, i. e. there is no a possibility to change the launching angle the wave polarization. Due to the long distance between the last focusing mirror and the center TJ-II vessel the beam is quite wide at plasma border. The second line has a moveable mirror installed inside the TJ-II vessel. To get high absorption efficiency and a narrow energy deposition profile the internal mirror focuses the wave beam at plasma center. The beam width is about 2 cm. To get more flexibility in experiments on heating and current drive the first transmission line needs to be upgraded. The designs is presented in this report. It includes and internal mirror to focus the beam and to change the injection angle. A polarizer consisting in two corrugated mirrors will be incorporated to get any wave polarization. Two mirrors with an array of coupling holes and calorimetric measurements of the energy absorbed in the barrier window will permit the estimation of the microwave power launched the TJ-II. (Author) 13 refs

[en] The effects of radial electric fields on the non collisional losses, asymmetries at plasma border and on the Vacuum Vessel and trapping fractions for 0.1 1 KeV electrons in TJ-II are analysed. This study complements a series, already published, for ions, therefore only the main differences are stressed. Many of these effect are similar for electrons and ions, mainly the drastic decrease of losses with the electric field, the increasing peripherical loss concentration, the strong accumulation on the Hard Core (HC), the modification in the direction of the induced poloidal rotation, similar angular distributions for trapped particles, etc. Nevertheless, there appear also important differences, that in many cases are originated by the higher electron mobility, in particular a higher sensitivity to the electric field, as well to the intensity as to the sign, producing a faster drop in electron losses for positive potential and a higher asymmetry in the sign dependence. Most of these electron losses exit through the upper side of the plasma, the opposite happens for ions. The strong concentration on the HC appears, many, on the PL-1 plate (the one that is placed upside for toroidal angle φ=0 degree centigree), instead of the opposite PL-2 plate for ions.Finally, for the analysed energy range, there is no variation of electron trapping with the potential nor resonant effect. (Author) 8 refs

[en] It has been studied the physical mechanisms related with the spectral shift control method and their general positive effects on economical and non-proliferant aspects (extension of the fuel cycle length and low proliferation index). This method has been extended to non-hydrogenous fuel cells of high moderator/fuel ratio: heavy water cells have been controlled by graphite rods; graphite-moderated and gas-cooled cells have been controlled by a changing mixture of heavy and light water. It has been carried out neutron and thermal analysis on a predesign of these types of fuel cells. We have studied its neutron optimization and their fuel cycles, temperature coefficients and proliferation indices. Finally, we have carried out a comparative analysis of the fuel cycles of conventionally controlled PWR and graphite-moderated, water-cooled and spectra shift controlled reactors. (author)

[en] In this paper one considers the influence of the different parameters on the determination of the uncertainty of the detection efficiency for ⁵⁵Fe when the counting technique of liquid scintillation is applied. The following parameters are considered: the relative probabilities of X and Auger emission so as their corresponding energies, the fluorescence yields Wsub(K) and Wsub(L) and the non-interaction probabilities of the emitted X photons. (author)

[en] Biomass possibilities as an energy source and ''agroenergetica'' concept are described. Then, the possibilities of radiotracers in research on agroenergy, mainly photosynthesis, plant metabolism and soil-plant relations are analyzed. Finally the use of radioactive sources for the treatment of lignocellulosic biomass and the conservation of amylaceus biomass are considered. (author)

[en] The main purpose of this work is to get an useful guide to carry out topical neutron flux measurements. Although the foil activation technique is used in the majority of the cases, other techniques, such as those based on fission chambers and self-powered neutron detectors, are also shown. Special interest is given to the description and application of corrections on the measurement of relative and absolute induced activities by several types of detectors (scintillators, G-M's and gas proportional counters). The thermal and epithermal neutron fluxes, as determined in this work, are conventional or effective (Westcott's fluxes), which are extensively used by the reactor experimentalists; however, we also give some expressions where they are related to the integrated neutron fluxes, which are used in neutron calculations. (author)

[en] The experimental work carried out in pilot plant scale for uranium extraction from clarified ore leach liquors, has allowed to obtain fluidized bed break through curves relationship, including the main variables involved in the equilibrium and kinetic of the process. Two calculations methods have been developed in order to predict the behaviour or the ion exchange column, working in periodic from and with countercurrent flows. These methods, called the efficiencies method and the constant feeds method, have been tried by batch-wise and continuous tests, reaching results very close to experimental values. (author)