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Studying monetary authority response to macroeconomic imbalances using the interest rate as a proxy variable for monetary policy became ineffective after the financial crisis, when central banks exhausted the effective capacity of interest rates by reaching the zero lower bound (ZLB). In an effort to analyse the unconventional response deployed by central banks, we present and estimate a modified reaction function that uses money supply as the operational instrument of monetary policy for the Federal Reserve and the European Central Bank, and we verify its utility as an explanatory instrument for the behaviour of the two monetary authorities. By applying our strategy, it is feasible to identify both monetary policy reaction with regard to the economic situation as well as other possible monetary authority concerns regarding governments' fiscal behaviour and the evolution of asset markets, regardless of the monetary policy applied at any given time. [ABSTRACT FROM AUTHOR]

A proper assessment of the cost-competitiveness and profitability of self-consumption systems is crucial to promoting the transition from grid-dependent to energy self-sufficient buildings. Most of the approaches found in the literature may not take into account economic parameters such as taxes, depreciation and the cost of financing, which have a significant effect on the economic profitability of an investment. Moreover, they only focus on discrete array powers and relatively high recording intervals when estimating the self-consumed energy. In order to manage the aforementioned challenges, a new method will be developed to size the PV generator in a PV self-consumption system which provides the NPV curve together with the self-consumption and self-sufficiency indices for a wide range of array powers which suits residential self-consumption systems. Two scenarios will be considered depending on whether the generated surplus electricity is wasted or it is remunerated from the grid operator. Results show that not only the chosen scenario but the electricity tariff may be key parameters when optimizing NPV. Furthermore, the impact of the recording interval may be significant when estimating NPV. Percentage errors of 11.4% and 33.6% may be reached when considering a recording interval of 15 and 60 min, respectively. • New method to sizing PV generator in self-consumption systems. • Net present value, self-consumption and self-sufficiency indices are provided. • Taxes, depreciation and the cost of financing have been considered. • The impact of the recording interval may be significant when estimating NPV. • Self-consumed electricity price is the most influential parameter on NPV. [ABSTRACT FROM AUTHOR]

Abstract Applications for sizing Photovoltaic (PV) self-consumption systems have been studied over recent years in order to achieve either an optimization of the cost of energy, the investment cost or any economic profitability criteria. However, PV self-consumption systems at the residential or small business level can be designed with the aims of reducing the electricity consumption from the conventional local grid and achieving competitiveness with grid electricity prices. These criteria will provide not only greater environmental benefits, security and independence of the grid but it will make the cost of PV self-consumption electricity competitive with electricity prices from the power grid. In this sense, this paper proposes a method to size the generator for a PV self-consumption system based on cost-competitiveness, maximizing direct self-consumption. The method will be applied for three different households located in the south of Spain using the household daily consumption and generation profiles for a single year. However, the method here illustrated can be applied to other countries. The results obtained suggest that residential direct PV self-consumption systems with an annual global irradiation at the optimal tilt angle higher than 1000 kWh/(m2·year) may be a feasible investment to future owners of these systems. Highlights • A method to size PV generators based on the cost of PV self-consumed electricity has been developed. • The method is based on cost–competitiveness, maximizing direct self-consumption. • Real household load data have been used to illustrate the method. • In Spain PV self-consumption may be cost-competitive for irradiation >1000 kWh/(m2 y). • The method can be also used when considering batteries and Demand side Management. [ABSTRACT FROM AUTHOR]

Dimensional variations experienced by materials due to temperature changes are described by the Coefficient of Thermal Expansion (CTE), which is strongly dependent on microstructural features, especially on composites materials. Special attention is given in this work to Spheroidal Graphite Iron (SGI), for which the microstructure may be considered as a composite material formed by graphite particles embedded in a continuous matrix. In this work, a micromechanical approach, accounting for the manufacturing process, was used to compute the CTE of an eutectic SGI in an as-cast condition as a function of microstructural features and temperature. A cubic shaped Representative Volume Element (RVE) with Periodic Boundary Conditions (PBCs) was generated to model the microstructure of SGI. RVEs were formed by 12 non-overlapping spherical nodules embedded in a matrix with varying content of ferrite and perlite, and their size was determined by means of a convergence study. Using finite elements analysis, the macroscopic CTEs were computed for cooling and heating the material in the range from 25 °C to 500 °C. Using this micromechanical model, it was found that volumetric fractions of phases and temperature play a key role on the CTE. This coefficient increased by raising the temperature, increasing the volumetric fraction of ferrite, or decreasing the volumetric fraction of graphite. The manufacturing process had also an influence because plasticity occurred in the metallic matrix during the cooling stage of the casting process. Multivariable polynomial regressions were used on results of the micromechanical model to develop a mathematical expression and evaluate the CTE as a function of the volumetric fractions of phases and temperature. Results of the mathematical expression are compared with experimental data, finding a fairly good correlation between them. [ABSTRACT FROM AUTHOR]

Photovoltaics (PVs) provide new opportunities for radial distribution systems (RDSs) that feed electric vehicle charging stations (EVCSs). However, the accurate assessment of the combined technical impact is problematic because of the uncertainties of sources/loads. In previous research, we developed a technique to assess the impact of PV generation. This new study presents a general analytical technique (GAT) that evaluates the combined impact for an extended time frame. Specifically, the GAT effectively assesses the fulfilment of technical requirements for weekly RDS operating variables as specified in regulations. As our main objective is to improve the assessment accuracy of the EV and PV interaction in RDSs, the weekly assessment was extended to a one-year time period, during which it is possible to capture the total uncertainty. Also, correlation of input variables is handled. The computational cost of the GAT is lower than that associated with Monte-Carlo simulation, which is used to confirm the GAT accuracy. Although the results focus on an RDS located in Spain, GAT is applicable to any RDS and is scalable to different penetration levels. The numerical results show the impact of different correlated and non-correlated case studies on the voltage profile, apparent power flow in lines, and real loss. [ABSTRACT FROM AUTHOR]

This research describes a way to analyze voltage unbalance sensitivity for different maximum sizes of a single-phase photovoltaic system (SPPVS) with multiple PV penetration levels in a typical secondary radial distribution network (SRDN) in Spain. This analysis effectively assesses current requirements as specified in regulations concerning maximum size to be connected. It thus helps distribution network operators to define optimal limits, depending on their context. A stochastic assessment method is proposed to account for any random combination of SPPVSs in an SRDN. In addition, this method evaluates weekly voltage unbalance during a one-year time period, on the basis of 10-min intervals. More specifically, the voltage unbalance in SRDNs with SPPVSs is assessed for each 10-min interval by means of a probabilistic radial three-phase load flow (RTPLF). The results obtained show the maximum sizes of the SPPVS to be connected as a function of the PV penetration level in the SRDN, where high PV penetrations can produce voltage unbalance problems. [ABSTRACT FROM AUTHOR]

Highlights: [•] A method to optimize the reliability of an electric power system. [•] Reliability index is determined as the failure probability of the system. [•] Shuffled Frog-Leaping Algorithm and probabilistic load flow. [•] Improvement of the reliability index due to distributed generation. [Copyright &y& Elsevier]

Highlights: [•] Improvement for the optimal siting and sizing of distributed generation. [•] This paper presents a probabilistic three phase load flow in radial distribution networks. [•] The model takes into account the random nature of lower heat value of biomass. [•] A shuffled frog-leaping algorithm and probabilistic load flow are used. [•] Acceptable solutions are reached in a small number of iterations. [ABSTRACT FROM AUTHOR]

Abstract: The assessment of the technical impact of photovoltaic-distributed generation (PV-DG) units on radial distribution systems (RDSs) is complex because of the probabilistic nature of their output power and the diversity of potential sites where they can be installed. This type of evaluation thus requires a multivariate probabilistic analysis involving non-Gaussian correlated random variables. In a previous study, we applied an analytical technique to assess this technical impact for a single 10-min period. In the research presented in this paper, this technique was improved so that it could be applied during a full year, assuming 10-min intervals for PV and load profiles. This is the time period required to accurately assess the effects of stochastic PV inputs, and to determine the improvement of power quality (PQ) parameters, based on current regulations. This article describes a case study for a rural RDS located in the region of Andalusia in the south of Spain with spatially correlated PV-DG units. Our objective was to improve the analytical technique and also the accuracy of probabilistic methods. In our opinion, this can enhance the operation and planning of PV-DG in RDSs and provides a better understanding of the effects of spatial PV dependence structures. [Copyright &y& Elsevier]

Abstract: This paper shows that in order to solve a probabilistic three phase load flow in radial distribution networks, it is necessary to apply effective techniques that take into account their technical constraints. Among these constraints, voltage regulation is one of the principal problems to be addressed in photovoltaic distributed generation. This paper applies a new method utilizing Shuffled Frog-Leaping Algorithm and three phase probabilistic load flow combined with the Monte Carlo method to solve this problem. The objective function used is the power losses expected value. Acceptable solutions are reached in a small number of iterations. Results prove that the proposed method can be applied for the keeping of voltages within desired limits at all load nodes of a photovoltaic grid-connected system. To evaluate the performance of photovoltaic system this paper has developed a probabilistic model that takes into account the random nature of solar irradiance and load. Numerical applications are presented and considered regarding the unbalanced distribution system IEEE 13-nodes and including photovoltaic generators at several nodes. The results obtained show the decrease of the power losses due to the presence of distributed generation. [Copyright &y& Elsevier]

Abstract: This paper shows that the technical constraints must be considered in radial distribution networks, where the voltage regulation is one of the primary problems to be dealt in distributed generation systems based on biomass fueled engine. Loads and distributed generation production are modeled as random variables. Results prove that the proposed method can be applied for the keeping of voltages within desired limits at all load buses of a distribution system with biomass fueled gas engines. To evaluate the performance of this distribution system, this paper has developed a probabilistic model that takes into account the random nature of lower heat value of biomass and load. The Cornish–Fisher expansion is used for approximating quantiles of a random variable. This work introduces a hybrid method that utilizes a new optimization method based on swarm intelligence and probabilistic radial load flow. It is demonstrated the reduction in computation time achieved by the more efficient probabilistic load flow in comparison to Monte Carlo simulation. Acceptable solutions are reached in a smaller number of iterations. Therefore, convergence is more rapidly attained and computational cost is significantly lower than that required for Monte Carlo methods. [Copyright &y& Elsevier]

Abstract: This paper shows that in order to solve a probabilistic load flow in radial distribution networks, it is necessary to apply effective techniques that take into account their technical constraints. Among these constraints, voltage regulation is one of the principal problems to be addressed in photovoltaic distributed generation. Probabilistic load flows can be solved by analytical techniques as well as the Monte Carlo method. Our research study applied an analytical method that combined the cumulant method with the Cornish–Fisher expansion to solve this problem. The Monte Carlo method is used to compare the results of analytical method proposed. To evaluate the performance of photovoltaic distributed generation, this paper describes a probabilistic model that takes into account the random nature of solar irradiance. Therefore, load and photovoltaic distributed generation are modelled as independent/dependent random variables. The results obtained show that the technique proposed gave a better performance than the Monte Carlo method. This technique provided satisfactory solutions with a smaller number of iterations. Therefore, convergence was rapidly attained and computational cost was lower than that required for the Monte Carlo method. Besides, the results revealed how the Cornish–Fisher expansion had a better performance than the Gram–Charlier expansion, when input random variables were non-Gaussian. [Copyright &y& Elsevier]

Abstract: This paper reports the capacity of polypyrrole to reduce toxic hexavalent chromium (Cr(VI)). The influence of using different electrolytes during the polymer''s synthesis has been studied. To improve the reduction of Cr(VI), the parameters considered were the polypyrrole morphology and the amount of conducting polymer. Polypyrrole obtained by cyclic voltammetry at a low sweep rate using KBr as supporting electrolyte showed better performance for Cr(VI) reduction compared to coatings obtained by constant potential or cyclic voltammetry at high sweep rates. [Copyright &y& Elsevier]

Abstract: From an experiment conducted at the Florida State University Accelerator Laboratory with a 34MeV polarized 7Li beam bombarding a 12C target, we have obtained angular distributions and analyzing powers for states of 15N up to 20MeV in excitation energy. This study not only offers the possibility to assign spin and parity to several states in 15N, but also serves to obtain nuclear potential parameters used in Distorted Wave Born (DWBA) and Coupled Channel Born (CCBA) Approximations to generate theoretical angular distributions and vector analyzing powers that give the best description of the experimental data. Under the assumption that the reaction mechanism is a three nucleon transfer, the determination of shell model nucleonic configurations and spectroscopic factors is possible for the 15N states studied. [Copyright &y& Elsevier]

Abstract: The elastic deformation-recovery and mechanical properties of semi-crystalline polymers (HDPE, LDPE and their blends) were investigated. An optoelectronic technique based on a laser beam was used to analyze the behavior of the samples under radial stress. The laser technology showed that the recovery process develops in two stages. The first one is governed by the elastic component and the second and slower one is controlled by the inelastic component of the material. At low deformation, the overall recovery is attributed to the development of structural micro-domains generated when shearing the amorphous segments of the polymer. The radial Young modulus was also determined and compared to unidirectional measurements. At low deformation both techniques provide very similar values; nevertheless, the radial Young modulus departs significantly from the unidirectional one when increasing the number of cycles of deformation-recovery. [Copyright &y& Elsevier]

Nerve repair with tubes has a limit to regeneration depending upon the length of the gap. The characteristics of the guide, in terms of permeability, durability and adhesiveness, also influence regeneration. Considering the importance of the cellular component in regeneration, the development of artificial grafts, composed of a biocompatible nerve guide filled with a neurotropic matrix and seeded with Schwann cells (SCs), is an interesting option to enhance nerve regeneration and provide an alternative to the classical autologous nerve graft. We evaluated the ability of SCs transplanted into a nerve guide to improve regeneration after sciatic nerve resection, leaving a 6-mm gap, in the mouse. Syngeneic, isogeneic and autologous SCs were suspended in Matrigel and seeded in resorbable guides, and compared to acellular guides and to nerve autografts. The immunogenicity of the transplanted SCs clearly influenced the outcome. Transplants of autologous SCs resulted in only slightly lower levels of reinnervation than autografts, but higher recovery and number of regenerated axons than transplants of isologous and syngeneic SCs, and than acellular guides. Thus, by combined developments on nerve guides, extracellular matrix components and cell transplantation, an artificial graft has been designed that allows axonal regeneration across long gaps to levels comparable with an autograft. [ABSTRACT FROM AUTHOR]

Different cycles of industrial painting of steel and galvanised steel for making garden furniture were studied in order to overcome problems in covering tips, edges, sharp corners, commonly found in practice. Painting cycles, including cataphoresis or a Brugal® treatment, were used. The following characterisation was carried out: (a) measurement of the film thickness of the coating; (b) evaluation of the defects in the organic coating; (c) corrosion resistance in a salt fog chamber according to ASTM standard B 117 and (d) electrochemical impedance measurements.In general terms, test have yielded good results in assessing the best performance with different industrial cycles of painting. Good performance of every cycle has been shown in geometrically simple samples (tubes externally coated), while the corrosion behaviour of geometrically complex shapes (stretched net, round-drilled and stamped sheets) strictly depends on the selected painting cycle. The experimental results showed the effectiveness of the cataphoretic primer in increasing metal substrate coverage, so increasing corrosion resistance. The same was not obtained by using a Brugal® pre-treatment. Galvanised steel performed better than not galvanised one in the salt fog chamber test, but this result was not confirmed by electrochemical impedance spectroscopy (EIS) data. This electrochemical technique confirmed to be really a useful tool to clarify the behaviour of protected samples under accelerated corrosion conditions. [Copyright &y& Elsevier]

• An iterative multiphase HLF weighs PV uncertainties in secondary distribution networks. • An innovative combination of point-estimate method and affine arithmetic is adopted. • The interaction of background harmonic voltage on the PV harmonic current is modeled. • PV harmonic distortion and unbalance in secondary distribution networks are checked. Secondary radial distribution networks (SRDNs) have been increasingly affected by the uncertainties of harmonic sources associated with photovoltaic (PV) systems. The quantitative assessment of uncertainty propagation causing harmonic distortion and voltage unbalance can be successively handled by probabilistic or affine formulations of harmonic load flows (HLFs). This study developed a general analytical technique (GAT) for solving iterative multiphase HLFs in SRDNs with PV uncertainties. This technique merges the point-estimate method (PEM) and complex affine arithmetic (AA), combined with Legendre series approximation (LGSA). It also models the input correlation. One advantage of this GAT is that the iterative harmonic penetration (IHP) method, modeled for HLF, accounts for the interaction of background harmonic voltage with the PV harmonic current. The first prerequisite was evidently an uncertainty model for PV harmonic current. This paper presents the results for a real unbalanced three-phase SRDN and compares them with those obtained with the Monte-Carlo simulation (MCS). These confirmed the accuracy of GAT as well as its lower computational cost. The numerical results obtained showed that the GAT outperformed the incomplete GAT (IGAT), which is solely based on PEM and Cornish-Fisher expansion, thanks to the ability of AA to bound the outputs used in the LGSA. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• We present a CAT for solving iterative HLFs in RDS with PV uncertainties. • An innovative combination of the PEM, complex AA and LGSA is adopted. • The interaction between the background harmonic voltage and the PV harmonic current is. • modelled by IHP. • The simulation results showed the relevance of background harmonic interaction. Load and generation variations and the random nature of harmonics in non-linear devices (NLDs) are the source of multiple uncertainties that can be handled in harmonic load flows (HLFs) by probabilistic or interval formulations. The paper presents a new combined analytical technique (CAT) for iterative HLFs in the presence of correlated input uncertainties from photovoltaic (PV) systems in radial distribution systems (RDSs). This technique merges the point-estimate method (PEM), a probabilistic formulation, and complex affine arithmetic (AA), an interval formulation. It then uses the information derived in Legendre series approximation (LGSA) to approximate harmonic voltage distributions. Unlike other methods, this CAT includes iterative harmonic penetration (IHP), which provides a way to deal with the interaction of background harmonic voltage on PV harmonic current. The CAT was examined in a real ENDE 100 RDS system. Thanks to PEM and AA, the CAT significantly reduced the computational burden, an evident improvement over the Monte-Carlo simulation (MCS). Furthermore, the simulation results showed that it accurately reconstructed the harmonic voltage distributions (magnitude and phase angle). The iterative approach also underlines the relevance of background harmonic interaction. The CAT outperformed the incomplete CAT (ICAT), which was based solely on a probabilistic HLF formulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The indirect isoelectric effect boosts the glucose oxidase immobilization. • The flexible electrode is mechanically stable. • Biosensor performance toward glucose detection is improved by ZnO thin film. • The bioelectrode shows high sensibility and low LOD and LOQ. • The area covered by ZnO shows higher current density toward glucose oxidation. The present work shows the influence of the isoelectric indirect effect of the semiconductor ZnO in the enzymatic immobilization in a glucose biosensor. For this purpose, thin films based on Au and Au/ZnO were synthesized on a microstructured flexible substrate of polyamide filter membrane (P.F) and characterized by FESEM and XRD. Both flexible surfaces were used to immobilize glucose oxidase (GOx) enzyme mixed with ferrocene methanol (Fc) and multiwalled carbon nanotubes (GOx-Fc/MWCNT). Subsequently, these surfaces were used as working electrodes to be evaluated as glucose biosensors. The effect of the ZnO film was compared. The performance of the flexible substrate based on Au/GOx-Fc/MWCNT and Au/ZnO/GOx-Fc/MWCNT as glucose sensor showed similar linearity between 0 and 12 mM glucose; however a higher sensitivity (30.00 µA mM−1 cm−2) and lower limit of detection and quantification values were obtained (0.25 mM and 0.83 mM, respectively) when ZnO thin film was used. The results suggest that the ZnO thin film in junction with GOx enzyme enhance the immobilization process of the biocatalyst, resulting in an improvement of the glucose biosensor parameters. [ABSTRACT FROM AUTHOR]

The management of photovoltaic self-consumption systems is based mainly on updating energetic parameters such as generation and household power consumption connected via smart devices. The expected rapid increasing volume of data collected with different time resolutions is surely a topic that deserves great attention. The choice of a proper recording interval should balance the amount of monitored data and a proper energy analysis in order not only to take effective and timely decisions but also to help this technology to be more efficient. In the literature, only specific nominal array powers for annual reporting period or an array power range for daily reporting period have been considered. In this context, the error, when matching photovoltaic generation and household power consumption profiles considering different recording intervals (1, 10, 15, 30 and 60 min) and different reporting periods (daily and annual), will be estimated as a function of the array power (up to 10 kW p) for five households and a resident's association. Results depend on the reporting periods and it may be advisable to use 1 min and 10 min of recording intervals in order to estimate performance metrics in this type of system for a daily and annual basis, respectively. • Recording interval is a key parameter in PV distributed generation energy analysis. • Error matching between load and PV generation profiles has been estimated. • Different PV array powers, recording intervals and reporting periods are analyzed. • Individual households and residents association have been considered. • Proper recording intervals are provided for analyzing PV self-consumption systems. [ABSTRACT FROM AUTHOR]

In this study, the zeolite 13X was organomodified with gamma-aminobutyric acid (GABA). The zeolite modification decreased the sodium content which indicates that the modification is carried out by ion exchange mainly on the external surface of the zeolite. The modification process with GABA created edges and smaller particles which correspond to the partial transformation from zeolite X (FAU) into zeolites Y , SOD, and GIS. The chemical environment changed by modifying the zeolite 13X with GABA, this helped to retain creatinine and urea. This type of material is promising for medical applications in dialysis devices due to the relatively rapid removal of uremic toxins. Image 1 • The zeolite NaX was organomodified with GABA through ion exchange. • Ion exchange occurs mainly on the external surface of the zeolite. • The modification process with GABA partially transforms zeolite NaX into zeolites Y, SOD and GIS. • The modification process with GABA improved the removal efficiency of creatinine and urea. [ABSTRACT FROM AUTHOR]

In this work, the effect of ultraviolet radiation (λ = 367 nm) on the synthesis of di-thiourea cadmium chloride crystals by the chemical bath technique was studied. The results were analyzed and characterized by different techniques: X-ray diffraction (XRD), Raman scattering, scanning electron microscopy (SEM) and thermo-gravimetric analysis (TGA). It was found that the effect of ultraviolet radiation (UV) on the crystals causes a preferential growth in the (0 0 1) and (0 2 0) planes due to an increase in the formation of the Cd Cl and CS bonds caused by UV radiation. A morphological change was observed in the crystals assisted by UV radiation, and finally, it was found that the decomposition of the crystals starts from 497 K thus transforming the di-thiourea cadmium chloride into cadmium sulfide. Also, the growth rate is increased by incorporating ultraviolet radiation into the reaction. [ABSTRACT FROM AUTHOR]

Abstract: Electric energy production with photovoltaic (PV)/thermal solar hybrid systems can be enhanced with the employment of a bifacial PV module. Experimental model of a PV/thermal hybrid system with such a module was constructed and studied. To make use of both active surfaces of the bifacial PV module, we designed and made an original water-heating planar collector and a set of reflecting planes. The heat collector was transparent in the visible and near-infrared spectral regions, which makes it compatible with the PV module made of crystalline Si. The estimated overall solar energy utilization efficiency for the system related to the direct radiation flux is of the order of 60%, with an electric efficiency of 16.4%. [Copyright &y& Elsevier]

Blends of polypropylene (PP) with 0 to 100 wt% of polypropylene grafted with acrylic acid (AA-g-PP) were used to promote the adhesion to polyamide 6 (PA 6) in a three-layer coextruded film without using an additional adhesive or tie-layer. The effect of modified polymer content and its molecular weight on interfacial adhesion between PP and PA 6 was determined by T-peel strength measurements. The effect of melt temperature and bonding time on peel strength was determined. Oxygen and water vapor transmission rates of the films were measured. The peel strength of fusion bonded layers of PP/AA-g-PP blends with PA 6 strongly depends on bonding temperature and time, as well as on the molecular weight of the functionalized polymer. The peeled films surfaces were characterized using FTIR-ATR and scanning electron microscopy (SEM). Tensile properties of three-layer films, made up of PA 6 as the central layer and PP/AA-g-PP blends as the two external layers, are improved with increase in the acrylic acid (AA) content in the blend. The formation of an in situ copolymer between AA in the blend and the terminal amine groups of PA 6 was confirmed by the Moalu test. [ABSTRACT FROM AUTHOR]

Quercus pollen and meteorological data for several years from eight sites in Spain have been statistically analysed to select the threshold temperature and calculate the mean heat accumulation for predicting the Quercus pollination start in different climatic areas. The growing degree days method, which assumes the daily temperature varies as a sine wave, was used for heat accumulation calculations. Threshold temperatures between 4 and 12 °C were chosen using linear regression equations forced through the origin and their root mean square error (RMSE) of predicted against the observed dates for each observation site. Above the threshold, the average growing degree days (up to 1999) for the studied years was taken as the predictor value. Results showed a relationship between the selected threshold and elevation and a stronger and statistically significant correlation between threshold and yearly mean temperature, for each site. Regression analysis indicated that the selected threshold and the calculated heat accumulation were optimum for most of the localities. The validity of the results was tested using the meteorological data for the year 2000 as independent variable and this confirmed that there were only a few days difference between the predicted and observed day of the first pollen release for most of the studied localities. [Copyright &y& Elsevier]

Studies the improved structural properties of silicon oxide sol-gel semiconductor films. Oxygen diffusion coefficient; Raman spectra for a silicon oxide coating with and without the alumin particles; Zeta potential versus the pH of solutions containing alpha-aluminum oxide and silicon oxide particles suspended in water.