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The removal of water-soluble organics compounds in oilfield produced water (OPW) is currently one of the biggest challenges to meet the environmental legislation, as conventional remediation focuses mainly on removing solids and the dispersed oil fraction. Naphthenic acids (NAs) are present in significant amounts in water-soluble organics compounds; therefore, this work milestone is to properly understand the adsorption process by using an acutely recalcitrant O2-NA as WSO model. For this, a comprehensive screening of commercial adsorbents and waste was tested for NAs remediation, assessing also the influence of adsorbent properties and functionalities. Afterwards, there were selected the resins MN 202 and L 493 as adsorbents to further evaluate the regeneration and other variables such as temperature, pH and salt content, focusing on on-site offshore conditions. The initial screening and the equilibrium data suggest that characteristics such as surface area, pore diameter, and ionic form have a great influence on the adsorption process. Furthermore, the adsorption mechanisms involve anion exchange and hydrophobic interactions, showing a transition between multilayer to monolayer adsorption with the increase of the adsorbent dosage and the kinetics, while increasing NA encourages pore diffusion, resulting in irreversible adsorption. The use of eluents, while avoiding irreversible adsorption, allows recovering the adsorbent, improving the process feasibility at the targeted conditions.

The discharge of inadequately treated or untreated industrial wastewaters has greatly contributed to the release of contaminants into the environment, including toxic metals. Toxic metals are persistent and bioaccumulative, being their removal from wastewaters prior to release into water bodies of great concern. Literature reports the use of brown marine macroalgae for toxic metals removal from aqueous solutions as an economic and eco-friendly technique, even when applied to diluted solutions. Minor attention has been given to the application of this technique in the treatment of real wastewaters, which present a complex composition that can compromise the biosorption performance. Therefore, the main goal of this comprehensive review is to critically outline studies that: (i) applied brown marine macroalgae as natural cation exchanger for toxic metals removal from real and complex matrices; (ii) optimised the biosorption process in a fixed-bed column, which was further scaled-up to pilot plants. An overview of toxic metals sources, chemistry and toxicity, which are relevant aspects to understand and develop treatment techniques, is initially presented. The problem of water resources pollution by toxic metals and more specifically the participation of metal finishing industries in the environmental contamination are issues also covered. The current and potential decontamination methods are presented including a discussion of their advantages and drawbacks. The literature on biosorption was reviewed in detail, considering especially the ion exchange properties of cell wall constituents, such as alginate and fucoidan, and their role in metal sequestration. Besides that, a detailed description of biosorption process design, especially in continuous mode, and the application of mechanistic models is addressed.

One of the largest wastewater flows generated in the oil and gas industry is produced water (PW), which can come from oil fields, gas fields or a combination of oil and gas fields. This effluent has a complex and variable chemical composition; it contains a significant amount, sometimes up to 500 mg L−1, of water soluble organic compounds (WSO) that are not easily removed by conventional physical-chemical treatment as coagulation and flotation. With the intensification in worldwide industrial activities, the generation of PW has consequently also increased and, from the environmental point of view, it is of fundamental importance to point out the alternatives for its proper management, in order to comply with legislation around the world and to provide safe subsequent destination (reuse and/or disposal). Furthermore, the treatment of this effluent is challenging and requires a lot of attention from both industry and academy. In this context, adsorption is known as one of the most effective technologies for removing WSO in polishing steps, since it is a technique of simple installation and maintenance, with low cost. Thus, this paper aims to review and highlight in detail (i) the main characteristics of produced water and its different forms of reuse, (ii) the theoretical fundaments of the adsorption technique and (iii) through case studies, critically evaluate the technical feasibility of implementing adsorption towers in PW treatment units.

Red macro-algae Gracilaria caudata and Gracilaria cervicornis were used as cation exchangers for transition metals (copper, nickel and zinc) from a synthetic petrochemical wastewater. Scarce information is available in the literature about the use of red algae as natural cation exchanger and the effect of multicomponent aqueous matrix on the treatment performance. In the present work, the transition metals separation and recovery were evaluated considering the matrix effect. The ion exchange capacities for both red algae were near 1.2 mEq/g, which corresponds to the total amount of light metals present on the surface of raw algae. A heterogeneous model, considering 3 inflection points, was developed to enable the identification and quantification of the functional groups present on the biomass surface and the results obtained are in agreement with the total amount of light metals obtained by biomass digestion. Equilibrium and kinetic experiments were conducted using both raw algae and calcium loaded G. cervicornis. Cation exchange equilibrium was described by a Langmuir multicomponent model. The equilibrium affinity constants for the functional groups increases in the following order: nickel

Produced water treatment has become a challenge for the oil industry to meet environmental legislation requirements, due to several dissolved organic compounds, which are barely removed under conventional treatments. In this work, oil and grease removal from real offshore produced water samples was evaluated by a novel liquid-liquid extraction process, followed by efficient phase separation in a mixer-settler based on phase inversion. In this novel approach, a condensate–average stream composition collected from offshore oil production platforms was used as an extraction solvent to remove mainly dissolved compounds. This strategy treatment, which is considered unprecedented in the industry, may allow oil producers to overcome many logistic challenges, also reducing inputs consumption and costs. The synthetic condensate potential was also compared to n-hexane and n-heptane in batch tests. According to the results, solvent concentration and pH exerted a significant influence on the extraction efficiency. Only at pH 4 and 1:10 solvent ratio, excellent removal efficiencies were obtained. Another significant result observed in the study was the mixer-settler performance, which allowed instantaneous phase separation with high extraction efficiency. At 10% (v/v) of condensate, the flow rate of 10 L/h and at pH 4, the applied process was able to reach the PW requirements for discharge according to the Brazilian National Environment Council guidelines in a single extraction step, resulting in a final outlet stream containing oil and grease under 29 mg/L, measured according Standard Method 5520 – B (Partition Gravimetric Method). This work offers an alternative to overcome the main produced water management challenges faced by the oil industry, using more efficient and compact equipment and reduced operating costs since the inputs are available on the offshore oil production platforms.

Oilfield produced water treatment represent a global challenge due to the presence of several contaminants such as heavy metals and dissolved organic compounds. They cannot be removed by conventional equipment and may threat the environment when discarded. Hence, oil industry has the challenge of manage the produced water according to the disposal standards set by environmental agencies and, at the same time, overcome weight and space limitations in the platforms. Choosing the best technology involves the understanding of the process, construction and operational cost, along with the maintenance and management of the removed pollutants. In addition, different oilfield produced water composition and volume also lead to different options for its management. In this context, the study of technological routes such as liquid-liquid extraction is of great interest to the petroleum industry due to the variety of solvents and the different approaches available to accomplish the produced water treatment decontamination. Despite the extensive liquid-liquid extraction application for analysis and remediation of complex mixtures, there is no literature review on this topic. Thus, this paper presents a review of soluble organic compounds removal from oilfield produced water by the liquid-liquid extraction process. The novelty of each extraction method was highlighted and possible applications in the oil industry were identified.

A mechanistic and phenomenological model for multi-component cation exchange has been applied in order to describe the dynamic behavior of barium removal by seaweeds in batch and fixed-bed systems, instead of the empirical models usually applied. Initially, four macroalgae were tested as natural cation exchangers for barium removal: Arribadas, Gracilaria birdiae, Pelvetia canaliculata and Sargassum cymosum. Brown alga Pelvetia canaliculata showed the highest barium uptake capacity, mainly associated with the amount of carboxylic and sulfonic groups present in the biomass surface. A mechanistic model based on the mass action law was able to predict the cation exchange equilibrium for the Ba2+/Ca2+/H+ multi-component system, being able to determine the selectivity coefficients between all ionic species for the functional groups. The Pelvetia canaliculata in the calcium form, after acid pre-treatment was used for fixed-bed column tests. The operating capacity was 1.85 mEq/g (237 BV), treating 14 L of influent (0.45 L/g of natural resin) until the breakthrough point. Elution in counter-flow mode, using 1.0 M HCl as eluent, was fast and efficient (100%), using only 5 BV of eluent (181 g HCl/L resin; eluant ratio of 520%). The mass transfer model proposed, considering equilibrium given by the mass action law, was able to predict well the ion exchange process in batch or continuous operation mode during the saturation and elution steps for all chemical species in the liquid and solid phase.

The remediation of a real textile wastewater aiming its reuse in the textile industry was carried out by integrating two processes: (i) a chemical or electrochemical advanced oxidation process (AOP or EAOP) based on Fenton's reaction for organics degradation, and (ii) a cation exchange process using marine macroalgae for removal of the iron acting in the Fenton's reaction based processes. Four AOPs/EAOPs at acidic pH 2.8 were tested: Fenton, photo-Fenton with ultraviolet A (UVA) radiation (PF/UVA), electro-Fenton (EF) and photoelectro-Fenton with UVA radiation (PEF/UVA). These processes provided very high color removals. After a running time of 45 min, the color removals were 68–95% for the Fenton process, 76–94% for the EF process, 80–98% for the PF/UVA process and 85–100% for the PEF/UVA process. In contrast, the mineralization was negligible for all the processes, indicating the generation/presence of persistent colorless compounds. The PF process was selected as first treatment stage due to its ability for color removal and related lower costs. A set of six marine macroalgae (Gracilaria caudata, Gracilaria cervicornis, Ascophyllum nodosum, Fucus spiralis, Laminaria hyperborea and Pelvetia canaliculata) were tested for iron uptake. Laminaria hyperborea showed the highest ion exchange capacity and affinity for iron species. Its application allowed the removal of all the iron acting in the PF process (3.4 mg/L). The textile wastewater resulting from the application of PF process followed by cation exchange with Laminaria hyperborea was successfully reused in scouring, bleaching and dyeing processes.

This work presents the result of the growth of thin zirconium films on the GaN(0 0 0 1) surface under various conditions. In experiment were used the X-ray photoelectron spectroscopy (XPS) and low-energy electron diffraction (LEED) techniques, which allowed to investigate the chemical composition, bonding environment and surface reconstruction. It is shown that zirconium forms ZrN, ZrNxOy, ZrOx and ZrO2 compounds, depending on the selected experimental conditions: the pressure and annealing temperature. Such a varied zirconium growth behaviour is explained by the diffusion of oxygen and nitrogen in the created interface region.

Morphology of Ni/GaN contact formed at room temperature (RT) by Ni vapor deposition onto the (0 0 0 1)-oriented n-type GaN surface under ultrahigh vacuum, and morphological changes introduced by annealing were studied. Measurements were carried out in situ using XPS, UPS, LEED and STM. The WF of the Ni film of the mean thickness 1 nm equaled 4.1 eV. For thicker layers (≥2 nm), it increased to 5.1 eV. The Schottky barrier height of the Ni/GaN(0 0 0 1) contact formed at RT amounted to 1.20 eV. Annealing of the Ni/GaN contact at 650 °C resulted in Ga diffusion into the Ni film and Ni–Ga alloying. The dominating alloy phase was Ni3Ga. The alloying was accompanied by coalescence of Ni film grains into 3D islands of a Ni–Ga alloy. Annealing at 800 °C enriched the islands with Ga. The Ga-rich phases of NiGa and/or Ni3Ga2 were dominant in the alloy.

Atomic force microscopy (AFM) has become an important tool in surface science and nanotechnology. It is obvious that the intrinsic limitations of AFM must be understood in order to get useful information about surface structure of the material under study. The ability to recognize artifacts should assist in reliable evaluation of instrument operation and in reporting of data. In this paper, we discuss the most frequently encountered image artifacts in atomic force microscopy. A variety of artifacts are illustrated by the results obtained with the aid of contact AFM (C-AFM), which can help avoid misinterpretations. It is shown that, despite inaccuracies in AFM image generation, in many cases valuable information can be obtained.

During the last decade, functional materials, which simultaneously possess high transmission over the visible light range and good conductivity of electron or hole type electrical conduction at room temperature, have been the subject of interest of many researchers. In this work, (Ti-V)Ox thin films were deposited using the high energy reactive magnetron sputtering method and their structural, chemical, electrical and optical properties were characterized. In order to determine the material composition, energy dispersive spectroscopy measurements were performed and homogeneous concentration of titanium, vanadium and oxygen components as a function of thin film depth was revealed. High resolution transmission electron microscopy investigations as well as selected area electron diffraction patterns confirmed that the thin films were composed of the mixture of nanocrystalline TiO2-V2O5-V2O3 phases. The images of thin films investigated by atomic force microscope revealed a homogeneous, densely packed surface with RMS surface roughness of ca. 2.3 nm. X-ray photoelectron spectroscopy measurements showed that the surface of thin films consists of elements that are specific to the mixture of TiO2 and aforementioned vanadium oxides. Optical properties were determined on the basis of optical spectrophotometry measurements, and the high transmission level of the thin films was confirmed in the visible light range. Based on these results, the refractive index, extinction coefficient and optical band-gap width were estimated. In order to verify the possible application of these thin films in the field of transparent electronics the resistivity and I–V measurements of films deposited on silicon were performed.

Oxygen bombardment is used as the oxidation method to form an insulator on GaN substrate at room temperature. The surface of clean substrate and the Ga2O3/GaN interface are characterized in situ by X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and low-energy electron diffraction (LEED). XPS spectra of the Ga 2p core level show a peak shift of ∼1 eV from Ga O to Ga N bonding, demonstrating an oxide formation of Ga2O3. Electron affinity of the clean GaN surface amounts to 3.65 eV; the electron affinity of the Ga2O3 on GaN(0001) surface is 3.7 eV. Valence band offset (VBO) of the Ga2O3/GaN interface measured using XPS and UPS is 1.15 eV. After annealing the system at 500 °C the electron affinity and the VBO decrease to the values 3.5 and 0.35 eV, respectively.

Nanocrystalline (4–5 nm) Ce 1− x Ru x O 2 mixed oxides ( x = 0.03–0.16) were synthesized using water in oil microemulsion method. Morphology, microstructure and a phase composition of the samples subjected to heat treatment in oxidizing and reducing atmosphere were investigated by TEM, SEM-EDS-EBSD, XRD and XPS. Oxide with x = 0.11 was structurally stable in oxidizing atmosphere up to 550 °C but above this temperature it decomposed into Ru deficient, nanosized Ce 1− x Ru x O 2 and large (few μm) RuO 2 crystals. No phase separation was observed for Ce 0.97 Ru 0.03 O 2 even after heating at 800 °C. Doping with Ru decreases the size of ceria particles and strongly hinders their sintering at high temperatures. In hydrogen atmosphere a segregation of small (∼1 nm) Ru crystallites occurred at the surface of the Ce 0.89 Ru 0.11 O 2 mixed oxide. Only small increase of the mean crystallite size of Ru (to 2 nm) occurred after reduction at 1000 °C. The unique resistance of Ru to sintering is assigned to a special epitaxial orientation Ru (0 0 2)∥CeO 2 (1 1 1), which persisted up to the highest temperature of reduction, due to very strong surface bonding. Contrary to a situation in oxidizing atmosphere, doping with Ru had no significant effect on the sintering of ceria in hydrogen. Partial substitution of Ru for Ce strongly enhances the reducibility of ceria at low temperatures and its activity in catalytic combustion of CO and soot.

Introduction Although it is recognized that physical exercise is beneficial for health, by increasing the quality of life, by preventing the occurrence of chronic diseases and improving mental health, sport, can also be responsible for serious injuries which some may lead to death. A first estimation of these sports-related traumatic deaths was led in 2010: 246 deaths; the purpose of this work is to update it. Methods The sources for data collection were: media data sources (Internet, regional daily press), websites of sport federations or association and public agencies involved in sport, collection of firefighter's public institution and the ministry of Sports. The death had to be caused by an injury during sport practice from the 1st of January up to the 31st of December 2016 in mainland France. Occupational injuries were not included, cycling, walking and bathing-related deaths were not included unless the notion of sport practice was clearly mentioned. Sports were categorized in seven groups: aircraft motorized sports, aircraft non-motorized sports, hunting, watersports, mechanical sports, mountain sports, other sports. Results In total, 277 sports-related deaths were identified for the year 2016, which represents nearly 5 deaths per week in mainland France. They were mostly men with 87% of deaths (sex ratio M/F of 6.5). They were mostly adults between 30 and 70 years old (66%). 52% of deaths occurred during summertime (June–September), 34% occurred on weekends (Saturday and Sunday). Deaths most often occurred during mountain sports (45%), water sports (16%), aircraft non-motorized sports (11%), aircraft motorized sports (9%), mechanical sports (8%), hunting (4%) and other sports (6%). Conclusions This work has provided an estimate of the number sports-related traumatic deaths in mainland France. Within the limits of the collection method, this number was 277 in 2016. The sports leading to the greatest number of deaths were middle and high mountain sports and water sports. Some cases may have not been collected because of technical difficulties of access to information media, but also when the victims died later after hospitalization, the fate of the victim is not always reported in the media. Similar work was conducted in prospective for the year 2017, in order to access the information media in real time. It will allow minimizing bias of disappearance of online information. Data collection on the circumstances of the accident which led to the death, the risk factors of the person and his environment, his/her level and his/her practice, etc. could provide information to elaborate prevention programs.

Introduction Traumatic brain injury (TBI) is most often an acute event similar to other injuries. However, consequences of TBI can be very serious and affect all aspects of lives, including mental abilities and the personality of the victim. The impact on a person and his or her family can be devastating. The number of people suffering from TBI is difficult to assess accurately but can be approximate by the French medicalized information system program (“Programme de medicalisation des systems d’information” - PMSI): 130,000 patients are hospitalized for TBI each year in France. However, this database does not provide the causes of TBI yet, which is crucial for prevention purposes. The main objective of this work is to describe the causes of TBI induced by home and leisure injury (HLI) available in the “Enquete permanente sur les accidents de la vie courante” (EPAC) study. Methods The French HLI permanent survey, EPAC, started in France in 1986 in a dozen of hospital emergency departments (ED). All patients admitted in ED for HLI are included. After consenting, patients are included and detailed information is collected: where, when, how, who, what product is involved as well as the chronology of the injury and the care given. In this study, TBI was defined as: a brain commotion, a head contusion, a skull fracture or other brain injuries. All patients recorded in 2016, responding to TBI criteria and hospitalized at least one day were selected. The individual causes of TBI described in the free text were analyzed and recoded. Since causes of TBI are very different according to age, they were described separately for: Results In 2016, among the 119,260 patients victim of HLI, recorded in EPAC database, 2918 were hospitalized following their TBI (2.4%). They were more frequent among toddlers (7.3%) and elderly (8.6%) and less frequent among teenagers (0.7%) or young adults (0.8%). Among toddlers ( Conclusions TBI is a frequent reason of admission in ED, more particularly for young children and elderly. This study allows describing the causes of TBI, for which patients need hospitalization. Those causes are very different according to the age and need to be further explored to help building targeted prevention campaigns, more particularly for 65 years and over since causes are various and sometimes not well known.

The persistence of conventional synthetic plastic in the environment is increasingly considered as a source of ecological problem and has been motivated the research of biodegradable and biocompatible polymers. Polyhydroxyalkanoates (PHAs) are thermoplastic polyesters synthesized by several bacteria and Cupriavidus necator is the known one. Due to the high production cost of PHAs, the use of a cheaper carbon source or nutritional supplements are required in order to reduce the production cost. The aim of this research was to investigate the influence of biodiesel of rice bran oil as a low cost nutritional supplement in cultures of C. necator in mineral medium on the cell growth and production of poly(3-hydroxybutyrate) - P(3HB). For this, C. necator was cultivated in shake flasks of 500 mL with 150 mL of mineral medium at 30 °C for 24 h in 150 rpm. Samples were removed each 4 h for evaluation. The results demonstrate that the addition of biodiesel of rice bran oil as nutritional supplement in the culture of C. necator was viable, since its addition allows a cell growth with substrate consume reduction. Besides, the P(3HB) yield was 61% and 150% superior when biodiesel was used compared to the control medium using 30 g L − 1 and 15 g L − 1 , respectively.

Transparent Nd:YAG nanoceramics composed of nanosized grains were fabricated by high-pressure low temperature sintering technique (HPLT). Structural and morphological studies of the sintered pellets were carried out using X-ray powder diffraction and Transmission Electron Microscopy. The hardness of nanoceramics, extinction coefficient and transmittance spectra were measured and analyzed. The initial grain size of the YAG powder was 30 nm and no grain growth has taken place during the consolidation process. The density of the obtained nanoceramics was close to the theoretical density of YAG.

The transparent Nd:YAG nanoceramics composed of nanocrystalline grains were fabricated by hot-pressing technique. Their absorption and luminescence spectra were measured. The effect of Nd concentration on absorption and luminescence spectra was studied. It was found that the concentration strongly affects the luminescence spectra appearing in decrease of the intensities of 4 F 3/2 → 4 I 9/2 band compared to the 4 F 3/2 → 4 I 11/2 band. The spectra are also significantly broadened. Additionally the Judd–Ofelt analysis was performed and the radiative lifetimes were calculated. The Ω λ decreased with increasing sintering temperature, from 1.60, 2.86 and 5.14×10 −20 cm 2 at 800 °C down to 0.75, 2.44 and 3.70×10 −20 cm 2 for 1200 °C, respectively for λ =2,4,6. The mechanism of concentration quenching of Nd 3+ luminescence in YAG nanoceramics was briefly discussed.

Terbium-doped LaAlO 3 nanopowders were obtained by the Pechini method. The perovskite structure was confirmed by XRD data. LaAlO 3 was synthesized already at 700 °C. The crystalline size depends on annealing temperature and varies from 25 nm for 700 °C to 36 nm for 1000 °C. Obtained nanocrystals exhibit strong green emission from the 5 D 4 level, centered at 543.4 nm. Emission from the 5 D 3 level is also observed; its intensity decreases with increasing of Tb 3+ concentration. Emission from color centers is observed at about 730 nm, its intensity increases with annealing temperature and decreases at higher terbium concentration. Formation of the color center is due to excess of oxygen and La vacancies. A decay time of the 5 D 4 emission depends on crystalline size and weakly depends on Tb 3+ concentration (in the 0.5-5 at% range).

Tb 3+ :YAG nanocrystalline powders have been prepared by the sol-gel route. Structure and morphology of the obtained materials have been studied. The average grain sizes have been determined by X-ray powder diffraction measurements. Photo- and cathodoluminescence spectra of the Tb 3+ :Y 3 Al 5 O 12 powders have been measured. It has been found that the samples at low concentration demonstrate emission ascribable to the 5 D 3 →F J and 5 D 4 → 7 F J transitions. In particular, the concentration dependence of the luminescence spectra and lifetimes have been investigated as a function of the YAG grains sizes. It has been shown that the cross-relaxation responsible for the quenching of the 5 D 3 state depends on the nanocrystalline grains size.

An extension of the scheme of non-equilibrium thermodynamics developed previously is given for quantum mechanical systems. A master equation for the density matrix of the system follows from this scheme. Onsager relations are given and derived. Application to a spin system gives the Bloch equations. The application to a one-dimensional damped harmonic oscillator results in equations, which enable us to calculate the usual Green functions. For the last case we derive, as a new alternative, quantum mechanical Langevin equations. A new element, compared to the classical Langevin equations, is a random velocity. The correlation of the random velocity with the random force then results from the zero point motion of the oscillator. The application of mesoscopic non-equilibrium thermodynamics to these wellknown problems illustrates the usefullness of this method.

The reformulation of nonequilibrium thermodynamics, to include the treatment of thermodynamic fluctuations, is applied to the hydrodynamic fluctuations of a simple fluid. It is shown that the nonequilibrium thermodynamic scheme leads to the explicit form of the Fokker–Planck equation which describes the time behaviour of the probability distribution function of these hydrodynamic fluctuations as well as the irreversible processes which are connected with this behaviour.

A theory of mesoscopic nonequilibrium thermodynamics is proposed, incorporating into thermodynamics of irreversible processes the treatment of fluctuations of macroscopic variables, as well as of fluctuations of their distribution functions. The theory developed leads in a simple way to the multivariate Fokker–Planck equations obeyed by these fluctuations. The formalism developed also permits to derive Fokker–Planck–Langevin equations for the distribution function of the macroscopic variables. A brief discussion is given of the properties of the random force terms in these equations.

A closed macroscopic system with fluctuating local properties is treated as a thermodynamic system with internal degrees of freedom. Gibb’s entropy postulate is used to define the systems’ entropy as a functional of the probability density in internal coordinate space. It is shown that application of the scheme of thermodynamics of irreversible processes then leads directly to the theory of fluctuations as Markov processes described by a multivariate Fokker–Planck equation. In this perspective fluctuation theory may be said to have become integrated into non-equilibrium thermodynamics.

Niniejszy raport ma na celu poruszenie zagadnien z zakresu szeroko rozumianego procesu decyzyjnego, dotyczącego zarządzania przedsiebiorstwem w dlugim okresie, ktorego wynikiem powinien byc plan dzialania skutkujący maksymalizacją wzrostu wartości jednostki.This report aims to stir issues in the wider decision-making process for the management of the company in the long run, the result should be a plan of action that results in maximizing the growth of the individual.

We consider intrinsic convection near the meniscus in a sedimenting homogeneous suspension. We derive coupled equations for the volume velocity and the meniscus profile and suggest an iterative scheme to calculate both. The first order of this scheme is worked out and allows an estimate of the distortion of the intrinsic convection flow due to the meniscus.

An extension of Faxen's theorem is given for the case that n spheres move with arbitrary velocities through a fluid in non-uniform steady flow. Explicit expressions for the friction- and mutual friction tensors, valid to order R-3, where R is a typical distance between spheres, are obtained together with this extension. These expressions contain 2-, 3- and 4-sphere contributions. Brownian motion of n spheres as a consequence of fluid fluctuations is discussed on the basis of the relationships derived.

The spectrum of light, scattered from a fluid with a stationary temperature gradient, is calculated on the basis of fluctuating hydrodynamics. Explicit expressions are obtained for the spectrum of the scattered light which is no longer symmetric around the frequency of the incident light. In particular the difference in height and intensity of the Brillouin lines is given. Furthermore the shift in the position of the maximum of the Rayleigh line is calculated.

The systematic theory of multiple scattering which we gave in a previous paper is further elaborated for critical scattering. It is shown that in each order the multiple-scattering intensity near the critical point is in essence a contraction of consecutive uncorrelated single-scattering intensities. The anomaly of the critical depolarization factor is calculated and is found to be in quantitative agreement with recent experimental results. Double scattering corrections to the Ornstein-Zernike plot are discussed.

A scheme is presented to evaluate the drag on an infinite circular cylinder, at rest in a perpendicular uniform stationary flow. This scheme leads already in second approximation to very satisfactory values for the drag coefficient up to Reynolds number R = 10 and probably even up to R = 10 2 .

An expression for the force on a sphere moving with a time-dependent velocity through an incompressible fluid in nonstationary, nonhomogeneous flow is obtained for the case of arbitrary slip on the surface of the sphere.

A mean-field type expression for the short-time self-diffusion coefficient is proposed and compared to recent experimental data.

A statistical theory of the dielectric constant for a nonpolar multicomponent fluid mixture is presented. Explicit expressions are obtained for, e.g. , the extinction coefficient and the dispersion of the velocity of light for a binary liquid mixture in the critical region.

A previously developed scheme - to evaluate mobility and friction tensors of an arbitrary number of spherical particles suspended in an unbounded fluid - is extended to include the influence of a spherical wall bounding the suspension. If restricted to one particle the results generalize well-known formulae for two concentric spheres to the case of non-vanishing eccentricity.

A previously developed scheme to calculate hydrodynamic interactions between an arbitrary number of hard spheres in suspension is generalized to the case that the speheres consist of liquid drops. If the viscosity of the liquid in the drops tends to infinity one recovers the results for hard spheres with stick boundary conditions. Zero viscosity within the drops corresponds to hard sphere hydrodynamic interactions with slip boundary conditions.

Explicit expressions are derived for the free energy per spin, the z component of the magnetization per spin, the internal energy per spin, the time correlation functions of the z components of two spins and the time autocorrelation function of the z component of the magnetization for the finite a-cyclic XY model. It is shown that in the thermodynamic limit these expressions reduce to the expressions derived previously by various authors starting from the finite c-cyclic XY -model.

Starting from a hamiltonian describing nonrelativistic charged particles with spin, the conventional linear response theory to obtain the conductivity tensor of a many-body system is reviewed. A projection operator is then defined which yields the correct expression for the transverse part of the conductivity tensor in terms of the transverse part of a current-current commutator correlation function with a modified propagator. Furthermore one can show that a second projection operator may be defined which yields the transverse part of the impedance for transverse normal waves. The difficulties are discussed which arise if one attempts to derive an analogous expression for the longitudinal conductivity.

We extend our previously developed scheme to evaluate the static mobility tensors of an arbitrary number of spheres in a viscous fluid, to the case of finite frequencies.