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An ab initio quantum chemical study of the reaction profiles of the nucleophile particle formation in the interaction of methanol, methanthiol, and acetoxime with an undissociated molecule of alkali metal hydroxide is performed for the gas phase and also with the explicit inclusion of a dimethyl sulfoxide molecule into the calculation and with allowance made for solvation effects within the continuum model.

Layered ZnO microspheric particles were prepared by the thermal decomposition of layered hydrozincite (LZnHC), which was synthesized from zinc nitrate and urea in a water/PEG400 mixture. The influence of the starting reagents, their concentrations, and the amount of PEG in the water/PEG400 mixture on the particle growth was observed. The chemical aspect of the particle growth was proposed in the frame of the partial charge model (PCM), and the formation of [Zn(OH)(2)(OH(2))(4)](0) and [Zn(OH)(HCO(3))(OH(2))(3)](0) was predicted for the solid phase. The assumed growth mechanism, which follows the "nonclassical crystallization" concept of a self-assembling mechanism, was observed in situ by small-angle X-ray scattering (SAXS) and predicts the rapid formation of approximately 6 nm sized building units. The size of these nano building units, stable only in the reaction medium, remains nearly constant during the synthesis, as the concentration of the nano building units increases throughout the reaction. The nano building units connect into leaves of LZnHC with a thickness of 20 nm. These leaves of LZnHC are further agglomerated into porous, microsphere-like particles with sizes up to 4 μm.

Commencing with a brief survey of Lie-group theory and differential equations evolving on Lie groups, we describe a number of numerical algorithms designed to respect Lie-group structure: Runge–Kutta–Munthe-Kaas schemes, Fer and Magnus expansions. This is followed by derivation of the computational cost of Fer and Magnus expansions, whose conclusion is that for order four, six, and eight an appropriately discretized Magnus method is always cheaper than a Fer method of the same order. Each Lie-group method of the kind surveyed in this paper requires the computation of a matrix exponential. Classical methods, e.g., Krylov-subspace and rational approximants, may fail to map elements in a Lie algebra to a Lie group. Therefore we survey a number of approximants based on the splitting approach and demonstrate that their cost is compatible (and often superior) to classical methods.

We present a technology and magneto-mechanical milling chamber for the magneto-mechano-chemical synthesis (MMCS) of magneto-sensitive complex nanoparticles (MNC) comprising nanoparticles Fe 3 O 4 and anticancer drug doxorubicin (DOXO). Magnetic properties of MNC were studied with vibrating magnetometer and electron paramagnetic resonance. Under the influence of mechano-chemical and MMCS, the complex show a hysteresis curve, which is typical for soft ferromagnetic materials. We also demonstrate that Lewis lung carcinoma had a hysteresis loop typical for a weak soft ferromagnet in contrast to surrounding tissues, which were diamagnetic. Combined action of constant magnetic field and radio frequency moderate inductive hyperthermia (RFH) below 40°C and MNC was found to induce greater antitumor and antimetastatic effects as compared to conventional DOXO. Radiospectroscopy shows minimal activity of FeS-protein electron transport chain of mitochondria, and an increase in the content of non-heme iron complexes with nitric oxide in the tumor tissues under the influence of RFH and MNC. From the Clinical Editor This study reports on the top-down synthesis of magneto-sensitive complex nanoparticles comprised of Fe 3 O 4 nanoparticles and doxorubicin. Authors also found that Lewis lung carcinoma had a hysteresis loop typical for a weak soft ferromagnet in contrast to surrounding tissues, which were diamagnetic. Combined action of constant magnetic field and radio frequency induced moderate hyperthermia induced both antitumor and antimetastatic effects greater than conventional DOX alone.

This paper describes the use of extrapolation with Magnus methods for the solution of a system of linear differential equations. The idea is a generalization of extrapolation with symmetric methods for the numerical solution of ODEs, where each extrapolation step increases the order of the method by 2.

Hybrid organic−inorganic proton conducting gels (PWA/ICS−PPG or SiWA/ICS−PPG) were made from 3-isocyanatopropyltriethoxysilane and poly(propylene glycol)bis(2-aminopropyl ether), resulting in a hybrid silicon precursor (ICS−PPG) in which was dispersed phosphotungstic acid (PWA) or silicotungstic acid (SiWA) in ethanol. In this system, heteropoly acid takes on the additional role of catalyst, initiating the hydrolysis/condensation reactions of the sol−gel composite. The existence of amidonium ions [C(OH)NH+] was established from the IR and Raman spectra of PWA/ and SiWA/ICS−PPG composites below and close to the crystallization limits (70−75%). The crystallization of the Keggin ions inside the ICS−PPG host was determined from the XRD spectra of the composites and confirmed also using vibrational spectroscopy, which shows the appearance of H3O+ modes at 1700−1710 cm-1. The amidonium ions help in the immobilization of the negatively charged Keggin ions in the membranes, ensuring their uniform distribution in ...

Layered lithiated Co- and Ni-oxide powders and thin films with rhombohedral (R\({\bar 3}\)m) structure were prepared by a peroxo wet chemistry route from Li(I), Co(II) and Ni(II) acetate precursors and the addition of H2O2. XRD analysis revealed that xerogel films and powders possessed a typical layered structure. Layered (R\({\bar 3}\)m) Li0.99Co1.01O2 powder and Li0.97Co1.03O2 films were formed around 500°C, while Li0.93Ni1.07O2 powder and Li0.94Ni1.06O2 oxide films were prepared around 550°C. The stoichiometry of the oxide films and powders was dependent on the heat-treatment temperature. The structure of sols, gels, xerogels and thin films was established from XRD spectra and from the FT-IR spectra, confirming their layered structure.

We prepared transparent sol solution of tin(IV) oxide doped with various concentrations of europium or terbium from inorganic (chloride) precursors. Thin films were deposited by the dip-coating method on glass substrates and heated in the air up to 500°C. The doped SnO 2 films were transparent and have the same composition as the sol. AES analysis showed higher concentration of tin on the surface of films. SEM micrographs showed that the films were smooth and dense. X-ray diffraction indicated that films were amorphous and became crystalline after 8 h of heating. Optical characteristics like transmittance and cathodoluminescence were also investigated.

Sensitive methods for assessment of the hemostatic state are essential for providing adequate therapy to patients with β-thalassemia. The present study was designed to monitor the changes in the hemostatic state of a patient with β-thalassemia at the primary stage and under heparin treatment following splenectomy. The hemostatic state of the patient was assessed using conventional tests (activated partial thromboplastin time, prothrombin index, thrombin time), fibrinogen and D-dimer assays, thromboelastography (TEG), thrombin generation test, and a novel thrombodynamics clot growth assay. Thrombodynamics parameters indicated the hypercoagulation state on the primary evaluation which progressed after splenectomy: stationary clot growth velocity increased from 32 to 38 μm/min (normal range 20-30 μm/min). Hypercoagulation state was confirmed by Doppler echocardiography, which detected portal vein thrombosis on day 23 after surgery. The results of the other tests' parameters were in the normal ranges before splenectomy. The TEG parameters were sensitive to low molecular weight heparin (LMWH) injections; but the values were close to the normal ranges before and after injections. The thrombodynamics assay demonstrated a high sensitivity to LMWH injections, and registered a decrease of the hypercoagulability in the course of therapy (P < 0.05). TGT was not performed during LMWH therapy. This clinical case demonstrates the potential of the thrombodynamics assay to serve as a sensitive method for coagulation system monitoring and prediction of prothrombotic tendencies in patients with hemolytic anemias.

A new class of spectral methods for solving two-point boundary value problems for linear ordinary differential equations is presented in the paper. Although these methods are based on trigonometric functions, they can be used for solving periodic as well as nonperiodic problems. Instead of using basis functions periodic on a given interval−1,1, we use functions periodic on a wider interval. The numerical solution of the given problem is sought in terms of the half-range Chebyshev-Fourier (HCF) series, a reorganization of the classical Fourier series using half-range Chebyshev polynomials of the first and second kind which were first introduced by Huybrechs (2010) and further analyzed by Orel and Perne (2012). The numerical solution is constructed as a HCF series via differentiation and multiplication matrices. Moreover, the construction of the method, error analysis, convergence results, and some numerical examples are presented in the paper. The decay of the maximal absolute error according to the truncation numberNfor the new class of Chebyshev-Fourier-collocation (CFC) methods is compared to the decay of the error for the standard class of Chebyshev-collocation (CC) methods.

In our recent publication we reported the FT-IR spectroscopic analysis of Ni-oxide films [A. Surca, B. Orel, B. Pihlar, P. Bukovec, J. Electroanal. Chem. 408 (1996) 83] prepared from aqueous sols containing a nickel sulphate precursor and polyvinylalcohol as an additive to improve the optical quality of the films. Films with improved adherence on ITO coated glass were deposited via the sol-gel route using a dip-coating technique from sols containing in addition a nickel sulphate precursor 3-aminopropyltrimethoxysilane (3-APMS). Heat treatment at 300°C produced Ni(Si)-oxide films whose IR spectra resemble the α(II)-Ni(OH)2 phase with NiO (bunsenite) nanocrystalline inclusions as was shown by X-ray diffraction analysis. The electrochromic effect with colouring/bleaching changes up to 55% was noted in 0.1 M LiOH. The colouration efficiency (ν) which is defined as the change in optical density per unit of inserted charge (ΔOD/Q) was up to 26 cm2C−1. Evolution of newly formed phases appearing during extensive (up to 200 cycles) potential cycling revealed the transformation of the as-deposited α(II)-Ni(OH)2 phase to β(III)-NiOOH and β(II)-Ni(OH) phases. In films cycled potentially more than 150 times in 0.1 M LiOH an irreversible transformation of the β(III)-NiOOH phase into the γ(III)-NiOOH phase was observed. From these results it was concluded that Ni(Si)-oxide films follow the Bode scheme [H. Bode, K. Dehmelt, J. Witte, Electrochim. Acta 11 (1966) 1079] when cycled potentially in protic electrolyte.

X-ray photoelectron spectroscopy (XPS) is used in two distinct ways for the analysis of thin films, such as those used as the basis for electrochromic devices. Firstly it is used for quantification of the stoichiometry and for measurement of the amount of intercalated material, and secondly, for gaining information on the chemical states present. Chemical shifts in XPS are sensitive to changes in the dielectric properties of the material under observation. A well established method for the correlation of these changes is based on the direct relationship between the Auger parameter (AP), derived from the spectrum, and the electronic polarisability of the ionic lattice. Electrochromic materials, such as V2O5, undergo phase changes during the course of intercalation of lithium ions. The Auger parameter is only sensitive to crystalline phase when this is associated with a large change in lattice polarisability. The phase changes on intercalation of V2O5 arise because intercalation occurs in stages, corresponding to the sequential filling of specific sites. The lithium ions have a strong polarising influence and thus AP should show a distinct dependence on phase and degree of intercalation. In this paper we show that this effect can be observed as a result of electrochemical intercalation of thin films and also that it is not masked by changes that might occur during movement of samples between cell and spectrometer as long as this is done under a protective atmosphere. However, the change in AP on intercalation is not fully recovered on de-intercalation. The implications of this are discussed in the paper

The research of animals with Guerin carcinoma has shown, that magneto-mechano-chemically synthesized magnetic nanocomplex on the basis of Fe3O4 nanoparticles with antitumor anthracycline row antibiotic doxorubicin and next local electromagnetic irradiation by spatially inhomogeneous constant magnetic and variable electromagnetic fields had a greater antitumor effect than conventional doxorubicin and magnetomechano-chemically synthesized magnetic nanocomplex without electromagnetic irradiation.

CeO2 and mixed CeO2/SnO2 coatings were prepared via the sol-gel method using the aqueous-based process. The addition of SnO2 to the mixed oxides coatings on their structural characteristics and optical properties were studied. The influence of added SnO2 in the CeO2 oxide coatings on the inserted/extracted charge was determined by chronocoulometric measurements. It was found that for 60 nm thick films the inserted/extracted charge was twice as large (Q = 10 mC/cm2) for films containing 17 mol% SnO2 if compared to CeO2.

Spectrally selective paint coatings based on silicon resin were prepared at different pigment volume concentration (PVC) ratios. Inorganic type pigment was found to be more suitable than the organic type for preparation of spectrally selective paint coatings. The temperature stability of thickness sensitivity spectrally selective (TSSS) paintcoatings was studied. The obtained results prove the possibility to the use the prepared coatings on laboratory scale for industrial application (coil-coating line) for solar collector.

Ni-oxide films prepared using the sol-gel route and dip-coating method have been investigated by X-ray diffraction, scanning electron microscopy, FT-IR spectroscopy, cyclic voltammetry and in situ UVVIS spectroelectrochemical methods. The sols were prepared from a nickel sulphate hexahydrate precursor with formamide and polyvinylalcohol added to improve the abrasive resistance of films and to increase the yield from dip-coating deposition method (100–120 μm per dipping cycle). The films consisted of 40% NiO crystalline phase with an average grain size of 10 to 30 A. The crystallites were incorporated into the amorphous phase which was found to resemble the α(II)-Ni(OH)2 phase. A pronounced electrochromic effect (ΔT ≈ 60%) was found by cycling the films in a 0.1 M LiOH electrolyte. This produced a maximum colouration efficiency (λ = 450 nm) of 35–40 cm2 C−1. Longitudinal optical (LO) mode of films potentially cycled up to 200 times have been detected by near-grazing incidence angle (NGIA) FT-IR reflection-absorption spectroscopy. The results revealed that the as-deposited films are progressively transformed to the β(II)-Ni(OH)2 phase which is then converted to the β(III)-NiOOH phase during further potential cycling. The influence of foreign ions (SO2−4, CO2−3, OH−) on the development of persistent electrochromism and stability of films was established and discussed in detail.

A simple method for theoretical prediction of optimum thickness to maximise the spectral selectivity of the absorber in photothermal conversion of solar energy is presented. The optical properties of the absorber are described in terms of Kubelka—Munk theory. The calculation is applied on black thickness-sensitive spectrally selective paint coatings. The obtained optimum thicknesses are compared with values which have been established by experimental optimisation.

A rapidly developing approach adding new dimensions to acetylene chemistry relying on employment of high basicity media such as alkali metal hydroxide suspensions in dimethyl sulfoxide (DMSO) has been, for the first time, investigated theoretically using ab initio models. Extending our recently introduced model of superbase catalysis with a nondissociated KOH (or NaOH) participation, we present here a model for a superbasic reaction center with the first solvation shell explicitly included. The alkali metal hydroxides in a DMSO solution were found to form KOH·5DMSO and NaOH·4DMSO complexes that are stabilized due to the interligand interaction. Our present MP2/6-311++G**//B3LYP/6-31+G* computations show that 1 and 2 water molecules can build themselves into the MOH close surrounding without substantially perturbing the DMSO ligands and easily travel between different insertion positions. Our results predict that the activation energies in the series of reactions of nucleophilic addition to a triple bond with water, methanol, methanethiol, sodium hydrosulfide, and acetone in the presence of dihydrated complexes should be larger than those obtained with the participation of monohydrated ones, which is in fair agreement with the experimental findings. The present model also explains an increase in the ethynylation reaction yield in the presence of water by suppression of the competitive enolization reaction.

The Kubelka-Munk theory is applied to the thickness-dependent diffuse reflectance of black-painted samples in the mid-IR. The calculated absorption and scattering coefficients are wavenumber-dependent. The reflectance of the nonideal backing also shows spectral features, which is attributed to the reflections from the boundary surface between the scattering medium and the substrate. The spectral dependence of scattering penetration depth is caused by the scattering and absorption processes. At some wavenumbers, the diffuse reflectance is independent of layer thickness, because of particular values of the parameters of the applied theory. The application of the Kubelka-Munk function is discussed.

Ion storage CeO2 and CeO2/SnO2 coatings were prepared by the sol-gel dip-coating method using an aqueous-based process. The influence of added SnO2 in the CeO2 oxide coatings on the inserted/extracted charge was determined by chronocoulometric measurements. It was found that for 60 nm thick film, the inserted/extracted charge was twice (Q=10 mC cm−2) as large for films containing 17 mol% SnO2, if compared to pure CeO2. The effect of the addition of SnO2 to the mixed oxide coatings on their optical properties and structural characteristics was studied.

Thickness-sensitive spectrally-selective (TSSS) paint coatings were prepared by using FeMnCuOx pigment in combinations with phenoxy and silicone resins. The spectral selectivity expressed as a ratio between solar absorptance (as) and thermal emittance (eT) was 0.92 0.14 for the first and 0.87 0.18 for the second type of the paint. The surface of phenoxy resin based coatings is characterized by pigment particles protruding from the surface, while silicone based paints exhibit a much smoother surface. Abrasion resistance and adhesion of both types of coatings were enhanced by cross linking the resin binder with diisocyanate hardener. Cured coatings withstand temperatures up to 135°C. Cross-linking and degradation mechanisms of both types of coatings were studied by using FT-IR spectroscopy and thermogravimetric measurements, cycling and ageing tests.

The title compound has been synthesized under solvothermal conditions by reacting vanadium(V) oxytriisopropoxide with terephthalic acid in N,N-dimethylformamide. A combination of synchrotron powder diffraction, infrared spectroscopy, scanning and transmission electron microscopy, and thermal and chemical analysis elucidated the chemical, structural and microstructural features of a new 2D layered inorganic-organic framework. Due to the low-crystallinity of the final material, its crystal structure has been solved from synchrotron X-ray powder diffraction data using a direct space global optimization technique and subsequent constraint Rietveld refinement. [V(4)O(4)(OH)(2)(O(2)CC(6)H(4)CO(2))(4)]·DMF crystallizes in the monoclinic system (space group P2/m (No. 10)); cell parameters: a = 20.923(4) Å, b = 5.963(4) Å, c = 20.425(1) Å, β = 123.70(6)°, V = 2120.1(9) Å(3), Z = 2. The overall structure can be described as an array of parallel 2D layers running along [-101] direction, consisting of two types of vanadium oxidation states and coordination polyhedra: face-shared trigonal prisms (V(4+)) and distorted corner-shared square pyramids (V(5+)). Both configurations form independent parallel chains oriented along the 2-fold symmetry crystallographic b-axis mutually interlinked with terephthalate ligands in a monodentate mode perpendicular to it. The morphology of the compound exhibits long nanofibers, with the growth direction along the layered [-101] axis. The magnetic susceptibility measurements show that the magnetic properties of [V(4)O(4)(OH)(2)(O(2)CC(6)H(4)CO(2))(4)]·DMF can be described by a linear antiferromagnetic chain model, with the isotropic exchange interaction of J = -75 K between the nearest V(4+) neighbours of S = 1/2.

The growth mechanism of ZnO is investigated by a combination of electron microscopy and in situ small-angle X-ray scattering (SAXS). The particles are prepared by the precipitation of zinc nitrate with urea. Depending on the reaction conditions, ZnO, hydrozincite, or a mixture of both phases is detected in our system. The molecular precursors and complexation reactions of the formation process are numerically predicted by the partial-charge model. The condensation and complexation reactions lead to the formation of nanoparticle building units up to a size of 10 nm. Afterwards, the nanoparticles immediately self-assemble into micro-sized particles.

An application of symplectic implicit Runge-Kutta (RK) integration schemes, the s-stage Gauss-Legendre Runge-Kutta (GLRK) methods of order 2s, for the numerical solution of molecular dynamics (MD) equation is described, The two-stage fourth-order GLRK method, the implicit midpoint rule, and the three-stage diagonally implicit RK method of order four are studied. The fixed-point iteration was used for solving the resulting nonlinear system of equations. The algorithms were applied to a complex system of N particles interacting through a Lennard-Jones potential. The proposed symplectic methods for MD integration permit a wide range of time steps, are highly accurate and stable, and are thus suitable for the MD integration

Cerium/vanadium mixed oxide films, designed for application in electrochemical cells and electrochemical devices, were obtained on glass substrates by the sol-gel process. An analysis of structural modification of these films, induced by ultrasonification, annealing and by introduction of lithium ions, was performed, using grazing incidence X-ray scattering (GISAXS) technique. Two-dimensional GISAXS spectra were measured at different grazing angles, starting from slightly below the critical angle. One-dimensional scattering curves were extracted from these spectra, showing the dependence of the scattering intensity on different components of the wave vector in the scattering plane. These extractions - "cuts" in differnt directions enable a specific film depth nanostructural profiling.

Nickel oxide films were prepared by chemical deposition on glass substrates using nickel sulphate and potassium persulphate in ammonia solution. Coatings dried in air and at 85°C were characterized by thermal analysis (TG and DTG), FT-IR spectroscopy and X-ray diffraction. The films could be formulated as hydrated forms of 4Ni(OH)2·NiOOH and Ni3O2(OH)4 respectively. The coatings lost water and oxygen on heating to give NiO.

Nocturnal temperature measurements of various infrared selective radiators performing radiative cooling have been carried out. Measured temperature differences between the radiators and ambient temperature were about 10°C. Radiating surfaces have been prepared by applying different kinds of paints on aluminium substrates. It was shown that the addition of a BaSO4 extender in the paint dispersion increased the cooling performance of the paint radiators. Comparisons between predicted cooling performances by calculations and measured ones are discussed in detail.

Thin solid films composed from monodispersed cupric oxide particles with average size about 0.06 μm and narrow distribution of sizes have been prepared by dip-coating technique. The thermal decomposition method has been applied for the preparation of particulate sols. Sols and corresponding gels have made from cupric acetate precursor and citric acid as chelating agent. Sols showed a tendency for gelling during 48 h when kept at 70°C. X-ray diffraction, scanning electron microscopy, thermogravimetric analysis and Fourier transform infrared spectroscopy have been found that the gel and the structural features of oxide coatings, xerogels and the corresponding intrmediate stages. It was found that the gel and xerogel consist of copper complexes with ammonia (-NH3), hydroxo (-OH) and carboxylate (-COO) moieties in the form of bridges, thus making possible an interlinkage between different copper ion complexes. Optical spectra revealed that a reddish-purple coating is produced on glass by dip-coating method. The efficiency of dip-coating procedures is high since 0.004±0.005 μm thick CuO films are obtained per dipping. A potential use of the CuO coatings on glass is in window glazing with shading properties for the luminous part of the solar radiation.

This paper describes a parallel implementation of implicit Runge–Kutta methods with real eigenvalues. The construction of collocation-type methods as well as of methods with the stability function below the main diagonal of the Pade tableau is described. A method for estimating the local error and an implementation of these methods on parallel machines are proposed.

The Clauss method was recommended by the WHO to measure plasma fibrinogen levels. The purpose of this study was to assess the application of test systems made by the RENAM Research-and-Production Association (Moscow) on different types of clinical laboratory analyzers to measure fibrinogen by the Clauss method. The calibration line is shown to be of major value in obtaining correct results on each coagulometer. The findings suggest the accuracy and reproducibility of the determination of fibrinogen concentrations by the Clauss when the REHAM test systems are used to measure fibrinogen concentrations on various analyzers if accurate calibration lines are obtained.

Cancer is often characterized as a chaotic, poorly regulated growth. Cancer can be viewed as a complex adaptive system. Complex adaptive systems can be described mathematically by nonlinear (chaos) theory including asymmetry, fractal structure and autocorrelation factor (Cramer, 1993). Atypical shape of tumor cells and chaotic structures of blood flow is one from characteristic of cancer process. Atypical change of cell shape in conglomerates of tumor cells and structure of blood flow is accompanied by increase of deterministic chaos (Baish & Jain, 2000; Orel & Dzyatkovskaya, 2000). Complex natural phenomena such as cancer are dynamical systems whose state changes by perturbation. The concept of deterministic chaos is hierarchical for host in contemporary ideas about role of chaos for potential application in oncology (Sedivy & Mader, 1997; Blazsek, 1992). The authors introduced concepts related to chaos theory, such as attractors, fractals and the LotkaVolterra equations, as potentially useful approaches to allow for the analysis of carcinogenic biological processes as related to selection and competition. In certain situations, these equations give chaotic, non-linear, and nonpredictable results. Given what is known about the enormous complexity of the carcinogenic process, use of models such as these may be perfectly justified, and might provide the theoretical framework that is so desperately needed in this age of data overload to make real progress in the understanding of human carcinogenesis (Garte, 2003). Entropy is a measure of disorder. The thermodynamic entropy of a cancerous cell is different from that of a normal cell due to the more disordered structure of the cancerous cell. The reversal of entropy flow in tumour tissues may halt tumour development due to reversed signal transmission in the tumour-host entity. This thermodynamic approach may help in the design of cancer therapy (Molnar et al., 2009). Transplanted animal tumors which can only be experimentally induced by transplanting living tumor cells significant influence on complex adaptive systems include developing of tumor formation for experimental animals. During recent years there has been increasing public concern on potential cancer risks from radiofrequency radiation emissions (Hardell &

In this paper the preparation of thin SnO2 : F doped coatings deposited by spray pyrolyses on black enamelled steel and glass substrates is described. The optical properties of the prepared coatings are determined and treated by Drude modeling. The spectral selectivity of low emittance black enamelled steel was as = 0.9 and eT = 0.13 (80°C) and the low emittance glass coatings exhibit thermal emittance of eT = 0.11 (80°C). These results prove that both types of coatings can be used either as spectrally selective coatings for collectors panels or as spectrally selective glass covers for solar collectorr.

Preparation of an SnO2 semiconducting powder doped with antimony (x=2.38 mol%) was achieved by co-precipitation. The unit cell parameters of the doped SnO2 powders were measured and their changes with dopant concentration were determined. Four-point sheet resistance measurements, together with optical and infrared spectra of the powder were taken in order to obtain a highly-conducting, low-emitting powder which could be used for antistatic paint preparation. Evolution of the phonon bands corresponding to Sn-O stretching modes as a function of dopant concentration were followed, and a model calculation based on an extended four-parametric Kurosawa relation was applied to the reflection spectra of differently doped powders. It was found that the frequency of the plasma oscillations shifts with dopant concentration, and the intensity of the reflectivity peaks was correlated with plasmon-phonon interactions. An additional negative reflection peak in the range 1100 to 1200 cm−1 was found in the reflection spectra of highly doped powders and was attributed to the coupled modes between the plasma oscillations and one of the phonon combinational or overtone modes of SnO2.

Plasmin inhibitor (PI) determination is an essential diagnostic method. The purpose of the study was to develop an amidolytic assay for estimating PI activity, by applying the test system made by RENAM (Moscow). The new system is based on purified plasmin (human plasma) with the activity attested by the international standards. The developed method shows precision and accuracy with low and normal PI activity. The pilot clinical trial in patients with sepsis had demonstrated that the PI activity determined by this method is associated with some hemostatic parameters (prothrombin index, thrombin generation) and a patient's status (septic shock, hepatic dysfunction).

Analyse des proprietes vibrationnelles IR des monocristaux de TeO 2 dans la region spectrale allant de 280 a 1000 cm −2 . On se propose de trouver certains details supplementaires dans le spectre des phonons de TeO 2 en mesurant le spectre des polaritons correspondant

Rational approximations to the exponential function with real, not necessarily distinct poles are studied in this paper. The orthogonality relation is established in order to show that the zeros of the collocation polynomial of the corresponding Runge-Kutta method are all real, simple and positive. It is proven, that approximants with the smallest error constant are the Restricted Pade approximants of Norsett. Some results concerning acceptability properties are given.

In this paper we describe the preparation of black zincated steel plates and zinc powders. Infrared reflection/absorption (6°, 78°), reflection (6°) and transmission spectroscopy have been used for identification of layers formed on the corresponding substrates. It was found that modification of the existing method proposed by Telkes is necessary in order to obtain zinc powder with sufficient solar absorptance. Colour strengths of the layers and powders formed have been correlated with the existence of various copper(I) and copper(II) oxides in the layers. A negative reflectance peak at 595 cm−1 has been detected in the reflectance spectrum of black zinc powder and its origine was attributed to the coupled νCuO phonon mode with free electron oscillations of metallic zinc.

The background to the spectral selectivity of thickness sensitive spectrally selective (TSSS) paint coatings is discussed from the chemical point of view. This means considering the solar absorptance (as) and thermal emittance (eT) of the TSSS paint coatings as a function of paint film thicknesses in terms of the degree of flocculation of the pigment dispersion and from the viewpoint of the relevant intermolecular interactions which influence the ability of the pigment particles to become distributed uniformly in the paint, thus increasing its colour strength. We investigated eight TSSS paint coatings based on the standard formulation of Solariselect® paint [Sol. Energy Mater. 18 (1989) 97], which is currently used for solar collector panels. The influence of carbon soot (C - Degussa FW2), inorganic pigment (F - Ferro 6331) and fumed silica thixotropic agent (Aerosil - Degussa) in TSSS paint coatings on the degree of their flocculation was determined from the infrared hemispherical reflectivity R (d)λ = 2.5 which was measured from the paint film thickness. The absorption coefficient for diffuse radiation (K) and the scattering coefficient (S) were determined by fitting the experimentally determined R (d)λ = 2.5 curves to a modified Kubelka-Munk function derived by Korte and Otto [Appl. Spectrosc. 43 (1988) 38]. Correlations between the type of black pigment (F and C) and elementary particle size and surface activity of fumed silica (Aerosil 380, 200 and 972) were established and compared with the experimentally determined solar absorptance values (as) of the corresponding TSSS paint coatings. Since fumed silica in spite of its small content (

Thickness sensitive spectrally selective (TSSS) paint coatings for solar collector panels are described and their chemical, mechanical and optical properties are summarized and measured. TSSS paint coatings (Solariselect®) are made by the coil-coating application method. Large scale samples have as = 0.92 and eT =0.38. Solar collector production was established since 1987. Performance tests showed that at least a 20% increase in performance has been obtained with Solariselect® paint coatings in comparison with painted spectrally non-selective coatings.

A solar collector panel produced from aluminium foil (0.25 mm) coated with a 2–3 μm thin film of black paint is described and characterized. The paint coating on aluminium possesses moderate spectral selectivity with a solar absorptance a s of 0.92 and a thermal emmitance e T of 0.38. The paint coating acts as a thickness sensitive spectrally selective coating which is black for solar radiation, but is thin enough to allow the low emitting aluminium surface to be seen through the pain film. The paint coating (Solariselect®) is made by an industrial coil-coating application process which assures high efficiency, excellent thickness control and consequently a highly reproducible spectrally selective paint coating. The influence of the paint composition on the physical and optical properties of the paint coatings are discussed in detail.

Cerium vanadate films on glass substrate were obtained by sol-gel process. The morphology of these nanostructured and porous films was studied by grazing-incidence small-angle X-ray scattering (GISAXS). The aim of the GISAXS study was to investigate the changes in grain sizes due to the temperature evolution with three different time intervals (5min., 15 min. and 30 min.) of annealing at 673 K. We found that the effects of the different times of annealing are diverse for surface and bulk properties of this V/Ce oxide. Although the increase in size is common to all the samples, it is far more pronounced in the bulk. The result is that for short annealing time grain sizes are bigger close to the surface, while this is reversed after long annealing. Generally, the annealing time is critical parameter in sol-gel preparation of the nanostructured vanadium oxide films, which are used as electrodes in new optoelectronic devices. This particular morphology is quite suitable for application in electrochromic devices, in an advanced electrochemical cell concept and efficient new solar cells.