Dispersion in a relativistic degenerate electron gas

Relativistic effects on dispersion in a degenerate electron gas are discussed by comparing known response functions derived relativistically (by Jancovici) and nonrelativistically (by Lindhard). The main distinguishing feature is one-photon pair creation, which leads to logarithmic singularities in the response functions. Dispersion curves for longitudinal waves have a similar tongue-like appearance in the relativistic and nonrelativistic case, with the main relativistic effects being on the Fermi speed and the cutoff frequency. For transverse waves the nonrelativistic treatment has a nonphysical feature near the cutoff frequency for large Fermi momenta, and this is attributed to an incorrect treatment of the electron spin. We find (with two important provisos) that one-photon pair creation is allowed in superdense plasmas, implying relatively strong coupling between transverse waves and pair creation.Comment: 17 pages, 9 figures. Submitted to Physical Review

Determining the Optimal Groundwater Control System Using FUZZY-GWCS Application

U cilju razvoja metodologije povodom rešavanja problema vezanih za odbranu od podzemnih voda i izbora optimalnog sistema odbrane od podzemnih voda, izrađena je namenska aplikacija FUZZY-GWCS (Fuzzy - Groundwater Control System) u Centru za Modeliranje Podzemnih Voda. Ovom aplikacijom se vrše matematički proračuni pomoću jedne od metoda fuzzy optimizacije - fuzzy analitičko hijerarhijskg procesa. Od niza ponuđenih menadžment scenarija sistema odbrane od podzemnih voda dobijenih primenom metode hidrodinamičkog modeliranja, aplikacijom FUZZY-GWCS se bira optimalno alternativno rešenje, analizirajući različite kriterijume i podkriterijume. U radu je prikazana primena ove aplikacije na površinskom kopu.In order to develop a methodology for solving problems related to groundwater defense, and choosing the optimal groundwater defense system, a purposeful application FUZZY-GWCS (Fuzzy - Groundwater Control System) was developed in the Groundwater Modeling Center. This application uses mathematical calculations using one of the fuzzy optimization methods - a fuzzy analytical hierarchical process. From a range of offered management scenarios of groundwater protection systems obtained using the hydrodynamic modeling method, the FUZZY-GWCS application chooses an optimal alternative solution, analyzing different criteria and sub-criteria. This paper shows using this application on a surface mine

Studies of ferrocene derivatives. I. The synthesis and high resolution 1H-NMR spectra of some (1-hydroxyalkyl)-and (1-hydroxy-1-methylalkyl) ferrocenes

(1-Hydroxyalkyl)- and (1-hydroxy-1-methylalkyl) ferrocenes (α-ferrocenyl carbinols) have been synthesized and their high resolution 1H-NMR spectra studied as a function of the stereochemistry of the substituted connected to the cyclopentadienyl ring. It was found that when α-ferrocenyl carbinol contains a chiral center in the substituent, the 2,5- and 3,4-positions in the cyclopentadienyl ring become pairwise diastereotopic and magnetically unequivalent

Structural and spectroscopic investigation of 1-acetyl-2-(4-ethoxy-3-methoxyphenyl) cyclopropane and its NLO activity

To identify promising compounds and to develop a potent non-linear optical material, the molecule 1-acetyl-2-(4-ethoxy-3-methoxyphenyl) cyclopropane (AEMC) was selected. FTIR and FT-Raman spectroscopy techniques were employed to predict the functional groups and vibrational modes of AEMC. Gaussian 09 W software was utilised to analyse the parameters of the optimised title compound. Reactive sites were forecasted using MEP plots. To clarify the chemical significance of the molecule, ELF and LOL are utilised. Furthermore, the presence of interactions within the molecule is confirmed by RDG analysis. The strong and weak hydrogen bonds between the non-bonding atoms of AEMC are studied with the aid of AIM analysis. Additionally, the material's capacity to produce non-linear effects (NLO) was ascertained by examining the linear polarizability and first order hyper polarizability values

Antitumor effects of vanillin based chalcone analogs in vitro

© 2020 Polish Pharmaceutical Society. All rights reserved. Chalcones, as a large group of organic compounds, are widely implemented in various types of anticancer therapeutics. These plant metabolites are present in fruits, vegetables, spices, and have anti-tumor, antiinflammation, immunomodulation, antibacterial and anti-oxidative activities, as well as many other pharmacological and biological effects. The aim of the present study was to investigate cytotoxic effects, type of cell death and mechanism of action of the newly synthesized vanillin based chalcone analogs, (CH1) and (CH2) on human colon cancer HCT-116 and noncancerous (control) MRC-5 cell lines. In order to compare the effects of vanillin based chalcone analogs on investigated cell lines, as reference substances cisplatin (cisPt) and dehydrozingerone (DHZ) were used. Investigation of antitumor effect of chalcone analogs on HCT-116 cells was carried out by three methods MTT assay, flow cytometry and immunofluorescence analysis. The result of our investigation indicated that newly synthesized vanillin based chalcone analogs expressed powerful antitumor effect on cancer cells (HCT-116 cell line), while their effect on healthy cells (MRC-5 cell line) was not statistically significant. Vanillin based chalcone analogs caused overexpression and activation of mitochondrial Bax protein and caspase-3 in HCT-116 cells, indicating that their mechanism of antitumor action was mediated through activation of the inner apoptotic pathway. These results indicate possible usefulness of CH1 and CH2 in antitumor therapy whether through its direct cytotoxic effect or as adjuvant therapy. Our results indicate possible usefulness of CH1 and CH2 vanillin based chalcone analogs in antitumor therapy

FORMALISMS, ANALYSIS, RESULTS AND ACCOMPLISHMENTS WITH POPULATION INVERSION OF MATERIALS

During six decades of quantum electronics, a vast majority of new types of quantum generators have been developed. Although the principle of population inversion has united different ranges of electromagnetic spectra (and respective quantum generators), the existence of the title laser without the population inversion, makes that the exception had confirmed the rule, i. e. that this title deserves to be discussed further. Developing of formalisms describing the operation of quantum generators, by now have produced several approaches, which must have a quantum mechanics base. For the practical reasons, negative coefficient of absorption is acquired using classic electromagnetics as well, however for the population purposes, quantum representation must be entered.A few levels of formalisms will be set in this paper, linked to quantum generators accenting the optical portion of the spectra. The lowest level descriptions are based on lumped circuits. This could be expanded to equivalents of other physical problems, using program packages developed for the electrical engineering application purposes (Spice, etc.). Schematics are defined at the macro as well as micro equivalent levels (atomic – electronic levels). The kinetic equations with simpler approach will be considered as well as simplified laser equations based on quantum/ semi-quantum approach. The use of Fourier analysis or other appropriate transformations leads to formulating the main five laser equations which serve as the base for various working regimes of quantum generators and amplifiers (free generation regime, Q switch, synchronization, operation with filters, two modes regime, regime with losses, etc.). The Lyapunov stability theorem has to be included here, etc.For some of the chosen types of quantum generator, analytical modeling will be analyzed as well as the results of program packages developed for the lasers dynamics, regimes and parameters. The systems pumped with electronic beams (relativistic) will be considered and the nuclear physics statements discussed which must be included at the beginning, in order to consider further necessary parts of the condensed – solid state theory and laser techniques, after slowing down towards thermal energies.Existing program packages provide fast modeling and visualization of laser energy distribution, temperature, modes, etc. in active material with or without the resonator. A modeling will be performed for the specified geometries and a temperature distribution in active material will be captured during operation of a chosen laser system. Different pump geometries will be compared. Contemporary lasers with the shortest existing pulse durations demand new formalisms. Areas of nonlinear optics and quantum electrody-namics, Glauber states and similar, are areas that have to be included. Two main formalisms thermodynamical and quantum mechanical with transition probabilities using perturbation methods and secondary quantization naturally had to be complemented if the Brillouin, Raman, Compton, soliton, fiber and other lasers are included more generally