Effect of differences in proton and neutron density distributions on fission barriers

The neutron and proton density distributions obtained in constrained Hartree-Fock-Bogolyubov calculations with the Gogny force along the fission paths of 232Th, 236U, 238U and 240Pu are analyzed. Significant differences in the multipole deformations of neutron and proton densities are found. The effect on potential energy surfaces and on barrier heights of an additional constraint imposing similar spatial distributions to neutrons and protons, as assumed in macroscopic-microscopic models, is studied.Comment: 5 pages in Latex, 4 figures in ep

State dependent δ\delta-pairing and spontaneous fission

We examine the fission barriers, mass parameters and spontaneous fission half lives of fermium isotopes within the framework of macroscopic-microscopic model with a $\delta$-pairing interaction. Four different macroscopic models are applied and studied. The results are compared to experimental data and to the corresponding monopole pairing ones. The half lives obtained in the $\delta$-pairing model are comparable with experimental data. The state-dependence of pairing has an important effect on the calculated fission half-lives.Comment: Proceedings of 10th Nuclear Physics Workshop, Kazimierz Dolny, Poland, September 24-28, 2003; Latex2e; 4 figure

Quantitative diagnostics of ancient paper using THz time-domain spectroscopy

In this work we have studied the terahertz spectra of modern artificially aged and ancient paper samples using terahertz time-domain spectroscopy. Hydrothermal artificial ageing was performed in closed and open reactors. Ancient paper samples were produced during the 15th century in European countries. The main aim of the work is the quantitative assessment of spectral feature observed by terahertz spectroscopy as a function of degradation. To this goal, the state of degradation of paper samples was characterized by crystallinity measurements obtained by using X-ray diffraction and by the degree of polymerization of cellulose polymers obtained by size exclusion chromatography. The behavior of the terahertz spectra was formerly investigated as a function of the hydration of paper samples. This allowed discriminating between the spectral features induced by the presence of water and those induced by degradation of paper. Results indicate clear dependences of spectral parameters from the evolution of crystallinity and the degree of polymerization. They can be used as a nondestructive analytical method to assess the state of degradation of ancient paper by terahertz spectroscopy

Algorithm and numerical modelling of macroscopic barriers for fission

A practical computing algorithm has been developed for calculating the macroscopic energy of nuclei. Four different models of the macroscopic energy are examined and their influence on the results is discussed.The results of the calculations are presented in the form of curves to illustrate how the different macroscopic models influence on the spontaneous fission energy barriers of super-heavy nuclei

Stream security particularities in Java

Regarding numerous threats connected with sending and storing confidential data, there is a problem of assuring the efficiency. As an answer to those needs, we discuss the SUN's Java Virtual Machine mechanism provided to assure security to a single object. Thanks to the mechanism of serialization in Java, it is possible to provide secure solution. In this paper, we compare the efficiency of algorithms such as DES, Blowfish, AES, RSA and ECC as means of securing serialization of an object

Intelligent Tutorial System LISE

Development of information technology results in creation of more and more advanced teaching assisting systems. The authors of the article made an attempt to design and use the adaptative educational system based on the technologies: J2EE, JSF and XML. Unlike most hitherto solutions, the authors propose a three-tier architecture of the system and its improvement with additional functionalities

Stream security particularities in Java

Regarding numerous threats connected with sending and storing confidential data, there is a problem of assuring the efficiency. As an answer to those needs, we discuss the SUN's Java Virtual Machine mechanism provided to assure security to a single object. Thanks to the mechanism of serialization in Java, it is possible to provide secure solution. In this paper, we compare the efficiency of algorithms such as DES, Blowfish, AES, RSA and ECC as means of securing serialization of an object

Application elasticity as the factor determining the choice of technology. Testing of the factors determining the choice of application technology

The learning creation interface constituting one of the most important elements incorporated inthe Adaptive System LISE has been discussed in the present paper. The technologies associatedwith the use of JSF and EJB, Swing as well as GUI Builder have been selected for the testing.JDBO and JDO packages have been used in order to compare various technologies ofconnection with the database. The tests have been carried out on the MySQL server and Sun JavaSystem Application was used as the application server. The obtained results enable the choice ofoptimal solution