Fuzzy model for the information and decision making support system for the CFM branch company

The aim of this work is to present the ways of improvement the management process in the CFM company, by developing and implementing the Management Information System (MIS). In the first chapter the characteristic of Car Fleet Management company is presented. The second chapter describes how MIS could support management of that type of company, as well as general and functional requirements of the computer application. Third chapter presents an example of methodology of solving selected decision-making problem using a fuzzy rule-based model

Heavy metal content of water exposed to cement lining in the water pipe

Mechanizm wymywania z cementu toksycznych metali ciężkich nie został jeszcze dokładnie rozpoznany. Istnieje wiele czynników mających wpływ na ten proces, jak np. jakość przepływającej wody, a zwłaszcza jej pH, zasadowość, temperatura, zawartość chloru itp. Wpływ mają także skład i mikrostruktura wykładziny cementowej rur wodociągowych. W badaniach modelowych określono zawartość wybranych metali ciężkich (ICP-OES, ICP-MS) w wodzie przed i po 6-miesięcznym czasie eksploatacji rurociągu z żeliwa sferoidalnego z wykładziną cementową. Stwierdzono, że zawartość pierwiastków śladowych (Ba, Fe, K, Ni, Mg, Na, Sr, Zn, V, Cd, Pb, Mn, Cu i As) w wodzie kontaktującej się zarówno z nową wykładziną cementową, jak i po 6-miesięcznej eksploatacji przewodu była niewielka, w większości przypadków poniżej progu detekcji (ICP-OES). Badania strukturalne wykładziny cementowej wykonane za pomocą skaningowej mikroskopii elektronowej wykazały, że cienka warstewka kalcytowa pokrywająca zaczyn cementowy na wewnętrznej powierzchni rury bardzo szybko uległa zniszczeniu, jednakże jej skład chemiczny nie uległ zmianie po 6-miesięcznej eksploatacji układu badawczego. W miejscach zniszczenia wykładziny cementowej stwierdzono obecność znacznej liczby igiełek ettringitu, świadczących o rozpoczynającej się korozji betonu.The mechanism governing the release of toxic heavy metals from cement is still far from being well understood. The process is influenced by a diversity of factors such as the quality of the water flowing in the pipes (especially its pH, alkalinity, temperature and chlorine content), or the composition and microstructure of the internal lining applied. This paper reports on model investigations into the presence of selected heavy metals (determined by ICP-OES and ICP-MS) in the water before and after 6-month service. It has been found that in the majority of instances the trace element content (Ba, Fe, K, Ni, Mg, Na, Sr, Zn, V, Cd, Pb, Mn, Cu and As) was below the detection threshold (ICP-OES), regardless of whether the water was exposed to a fresh lining or after six months of service. Structural examinations of the cement lining by scanning electron microscopy (SEM) have produced the following findings: the thin calcite layer covering the cement paste on the internal surface of the pipe was destroyed within a very short time, the chemical composition of the layer, however, remained unchanged after 6-month service of the pipe being tested. At the points of cement lining destruction a large number of ettringite needles was detected, which is indicative of the onset of concrete corrosion

Photoelectron energy loss spectroscopy: a versatile tool for material science

International audienceX-ray Photoelectron Spectroscopy (XPS) used in quantitative chemical analysis of solid surfaces requires subtraction of a broad background, arising from various energy loss mechanisms, to obtain reliable core level peak intensities. Besides single electron excitation, collective electron oscillations (plasmons) can be excited in the bulk and at the surface. Photoelectron energy loss spectroscopy (XPS-PEELS) is a non-destructive tool useful for both process control and thin film metrology. This review emphasizes its versatility to elucidate material research issues. The energy loss function (ELF) is useful for thin film growth optimization since it gives insight in valence electron density, hardness, optical band gap and interface properties such as adhesion and wetting. XPS-PEELS also provides depth and width of implanted atom profiles in solid targets, e.g. Ar nanobubbles in Al. Special emphasis is given to the retrieval of electronic properties from XPS-PEELS data. Since the ELF, q, is related to the q-averaged dielectric function, q, the latter can be obtained by taking into account multiple bulk and surface plasmon excitations. This task is rather simple in wide band gap materials where the ELF and the no-loss peak are clearly separated, as illustrated by amorphous silicon, amorphous carbon or Al oxide data. In contrast, in metals or small band gap materials, the broad asymmetric photoemission peak overlaps the ELF and low energy features in the ELF may be lost. A Fourier Transform (FT) method is proposed to analyze PEELS data, with the objective of retrieving such low energy excitations, e.g. inter band transitions. This FT method is compared with an empirical method based on a smooth cutoff of the zero-loss peak, using PEELS data obtained from Al2O3. Current developments of a quantum mechanical theory are crucial to obtain the respective contributions of intrinsic and extrinsic plasmon excitation (along with their interference) and to assess some approximations performed in classical treatments