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Abstract: A microcontroller-based device has been developed for continuous measurement of current distribution and acid stratification in commercial flooded lead-acid batteries. Acid density at four different levels is measured using micro reference cells and the current density is determined from potential drops along the grid. The measurement method, the full device and measurement results are presented and discussed. [Copyright &y& Elsevier]

Abstract: The Poisson–Boltzmann theory is still considered as an exact theory under low or even moderate electrolyte concentrations. As of today, however, just the analytical solutions in a single electrolyte were obtained, while people often meet mixed electrolytes in practical applications. Thus the analytical solutions of Poisson–Boltzmann equation (PBE) in different mixed electrolytes are still an important issue. The analytical solutions of PBE in mixed electrolytes with monovalent and bivalent counterions were firstly derived in the present study. The potential distribution and concentration profile curves in EDL were obtained with one dimensional space by the analytical solutions of PBE. The potential distribution curves of different mixtures showed that the power of the screen surface charge for bivalent counterion was stronger than that for monovalent counterion, thus the concentration of bivalent counterion in EDL was larger than that of monovalent counterion. [Copyright &y& Elsevier]

Abstract: Electrode geometry is abruptly truncated at the metal insulating boundary. A theoretical analysis has shown that disk-electrode geometry induces current and potential distributions that influence the impedance response in the high frequency domain. In this paper we investigate the extent of this influence on an experimental system displaying constant-phase element (CPE) behavior. We shall focus on the influence of these current distributions on the characterization of underlying CPE behavior from the analysis of the imaginary part of the impedance, although we shall also address results obtained from the complex non-linear fitting of impedance data to an equivalent circuit. The crossover from CPE behavior to this geometry-dominated regime establishes an upper cutoff in the experimental frequency range employed to characterize CPE response. We discuss the experimental conditions for which this crossover may prevent the analysis of experimental results to reveal the real underlying CPE behavior. The results and conclusions here obtained agree with previous theoretical modeling. Taking into account the limitations presented here can help to a better characterization and a deeper understanding of the frequency dispersion in the response of solid electrodes. [Copyright &y& Elsevier]

Abstract: The under-ground mushroom Tuber indicum is renowned for its economic, nutritional, ethnobotanical and ecological importance. For the development of sustainable harvest and conservation practices, better knowledge about the mushroom''s habitat is indispensable. However, few approaches allow monitoring T. indicum''s distribution on a large geographic scale. Apart from the difficulty to directly monitor them by Remote Sensing and GIS technology, a particular challenge arises from the sampling limitations for this seasonal mushroom. This problem is common in geology, where underground mineral resources must be mapped without direct observations. Geologists apply the ‘Weights of Evidence’ method for such situations, and this approach may have potential for underground mushrooms as well. We thus constructed potential habitat maps for T. indicum using the Weights of Evidence method. Based on field survey and published sources, ten influential indicators associated with T. indicum were selected and mapped for Longyang district in southwestern Yunnan, China. Two predictive models were established from independent environmental layers. In order to build better understanding of the models’ predictive ability, apart from the Receiver Operating Characteristic (ROC) curve, the Area Adjusted Frequency (AAF) approach was also applied for model evaluation. For the final map, the best-performing model was selected. The resulting habitat map could provide guidance for future conservation activities. [Copyright &y& Elsevier]

Abstract: The electronic conductivity of (NiO)0.01[(Y2O3)0.08(ZrO2)0.92]0.99 was measured with a modified ion blocking method at 1273K in the oxygen partial pressure (p(O2)) range of 10−3–10−17 MPa. At p(O2)>10−6 and <10−14 MPa, the electronic conductivity was proportional to the 1/4 and −1/4 power of p(O2) due to hole and electron conduction, respectively. The electron conductivity was obviously smaller for Ni-doped YSZ than for YSZ by a factor of 2.0 at p(O2) range of 10−14–10−17 MPa. The measured electronic conductivity of Ni-doped YSZ was used to calculate the oxygen potential distribution in the electrolyte under the ion blocking condition. The lower oxygen potential region in the electrolyte was in excellent agreement with the darkly colored region found in the Ni-doped YSZ electrolyte after the electronic conductivity measurements. [Copyright &y& Elsevier]

Abstract: The private and public agencies for nature protection often ask land managers to implement biodiversity conservation plans. Invertebrates constitute a substantial proportion of terrestrial and freshwater biodiversity and are critical to ecosystem functions. However, their inclusion in conservation planning and management is under represented, particularly in the Alps. In this paper we propose a new methodological solution and challenge for the identification of priority areas based on the integration of three approaches: invertebrate multi-taxa based; expert-based; and, GIS-based. The Trentino Province (eastern Italian Alps), was investigated as a case study. The first methodological step was to select a panel of nineteen experts which played a strategic role in the suggestion of 229 species, endangered or of mandatory conservation interest. The second step was to find objective criteria for species prioritisation. These criteria, crossed with the experts taxonomical and ecological knowledge resulted in a list of 70 focal invertebrate species. The third step was to integrate with the GIS-based approach data layers from the habitat requirements of each of the 70 focal species to generate potential spatial-distributional maps. Potential distribution maps gave information about the sites (priority areas) in which the highest number of focal species could concentrate, thus suggesting where to focus future monitoring efforts. Several priority areas resulted outside the protected ones. Alluvial forest and hop-hornbeam woods were the habitats with the highest number of focal species, and thus they represent the habitats of major conservation interest and concern, because they are usually small, fragmented, and near urbanised areas located in the bottom of the valleys. The relatively simple processes involved in species and potential habitat distribution proposed in this paper can be conducted with a minimal amount of data, making it an attractive tool when time and funds are in short supply. [Copyright &y& Elsevier]

Abstract: We use two ecological niche modeling methods, Maxent and GARP, to model the potential distribution of emerald ash borer (Agrilus planipennis, EAB) in its invaded (Canada, USA) and native range (eastern Asia). For each algorithm (Maxent and GARP), we constructed three different models based on native or invaded data or a combination thereof. All GARP models yielded higher area under the curve (AUC) values and had therefore higher discriminatory power than the corresponding Maxent models, and the area predicted as suitable by GARP in North America was generally larger and included most infested sites even at the known range edges. In Asia, habitat suitability predicted by both algorithms was low and models trained with invaded coordinates did not transfer well to the native range. We found that none of the Maxent models provided a prediction precise enough for reliable risk assessment and the development of management plans, but a GARP model trained in the native range performed well when validated with data from the invaded range. Based on this GARP model, EAB may be able to extend its North American range further south, north and west covering roughly half (49%) of the natural range of the most common affected ash species (Fraxinus americana, F. nigra, F. quadrangulata, and F. pennsylvanica). While our results demonstrate that native data may be useful for risk assessment of invasive species, a validation of early predictions based on these data is only possible with a time lag, which is lacking for most species. Due to uncertainties associated with ecological niche models for invaders, native data may not be sufficient at all times for long-term risk assessment. With regard to the latter, we recommend frequent re-evaluation of models based on more current monitoring. Combining ecological niche models with more mechanistic approaches based on experimental data may reduce uncertainty and improve risk assessment. [Copyright &y& Elsevier]

Abstract: The beaded lizard (Heloderma horridum) is listed as a threatened species in Mexico. Scientific research has been limited to two sites within its range (Chamela and Valle Motagua) outside of these two regions there have not been adequate surveys to define range limits or measure environmental correlates for defining suitable habitat. We constructed an ensemble model (EM) for the distribution of suitable habitat for H. horridum in both Mexico and Guatemala and then used that model to identify potential areas to focus conservation. We used nine presence-only modeling methods, and selected three to generate our EM. We used the EM to evaluate the efficacy of the existing Protected Natural Areas (PNAs) in Mexico and Guatemala for H. horridum. Also we used the best individual predictive model (Maxent) to obtain the most important factors for H. horridum presence and used them to analyse the habitat use; finally we used our predictive model to calculate niche breath for the species. The estimated potential distribution of H. horridum is 370,474km2; within this area we identified nine zones based on continuity and natural barriers. About 1.5% of the species distribution is under protection in the PNAs. The five most important factors for the presence of this species explained 78.2% of the generated model and are related to seasonality and soil cover, and these are used selectively. This species is closely associated with tropical deciduous forests, one of the most threatened ecosystems worldwide and is inadequately protected in both Mexico and Guatemala. Our results clearly show the necessity of a protection plan for this species. [Copyright &y& Elsevier]

India''s high renewable target might be achievable but it comes at a significant cost, given the nation''s already-stressed power system. That''s why it is important to get the policy design right from the beginning. The starting point should be a climate data analysis to assess the resource potential and its spatial and seasonal distribution. [Copyright &y& Elsevier]

Abstract: Using the theory of elliptic integrals and the mathematic trick, we obtain analytic distribution functions of the potential and the field on the central axis line generated by an elliptic ring uniformly charged and we make the discussion about it. The important properties of the potential and the field on the central axis line generated by an elliptic ring uniformly charged is shown. [Copyright &y& Elsevier]

Abstract: In this work, the importance of potential and current distribution analysis is highlighted as a key factor in the design of energy efficient electrocoagulation (EC) reactors. Although there are three types of distribution of current and potential (primary, secondary and tertiary), only primary potential and current density distributions were analyzed as a first approach. This approach simplifies the analysis by considering only cell geometry. This study included modeling of potential and current distribution and its impact on EC performance. The analysis showed the effect of cell geometry and electrode configuration on the distribution of potential in the cell, the current distribution on the anodes and the modification of a non-uniform distribution by changes to electrode configuration. The experimental evaluation of different electrode configurations showed that EC performance is enhanced when uniform potential and current density is achieved, and kinetics of anode (in this case aluminum) dissolution can be improved without having to change the applied current density. [Copyright &y& Elsevier]

Abstract: To study the coupled phenomena occurring in proton exchange membrane fuel cells, a two-phase, one-dimensional, non-isothermal model is developed. The model includes water phase change, proton transport in the membrane and electro-osmotic effect. The thinnest, but most complex layer in the membrane electrode assembly, catalyst layer, is considered an interfacial boundary between the gas diffusion layer and the membrane. Mass and heat transfer and electro-chemical reaction through the catalyst layer are formulated into equations, which are applied to boundary conditions for the gas diffusion layer and the membrane. Detail accounts of the boundary equations and the numerical solving procedure used in this work are given. The polarization curve is calculated at different oxygen pressures and compared with the experimental results. When the operating condition is changed along the polarization curve, the change of physicochemical variables in the membrane electrode assembly is studied. In particular, the over-potential diagram presents the usage of the electro-chemical energy at each layer of the membrane electrode assembly. As the fuel cell reaction becomes more limited by mass transfer, it is found that higher over-potential is uselessly concentrated on the cathode catalyst layer. The over-potential for the anode reaction was usually ignored in other studies, but the ratio of the anode over-potential to the cathode over-potential increases at a higher current condition. Water content is distributed more unevenly in the membrane, as the cell current is increased. That causes the proton conductivity of membrane to decrease and the water content to increase in the cathode side, which hampers O2 transfer. The effect of electro-osmotic property, one of important property of membrane, on cell performance is also studied. [Copyright &y& Elsevier]

Abstract: A developed mathematical model for calculating potential distribution inside the electrical double layer is explored in this paper based on the Poisson–Boltzmann equation. By modifying the ion concentration, we numerically simulated the potential profile inside the actual electrical double layer according to the zeta potential. Then a theoretical analysis on the streamwise electroosmotic velocity in microscale channel is presented. Furthermore, the expression of the electroosmotic velocity is significantly suppressed after considering the Helmboltz–Smolucbowski equation boundary conditions. The results show that the calculated electroosmotic values basically agree with the experimental ones. Therefore, this provides the data for micro- and nano-channels’ electrophoretic transport, as well as separation of neutral and charged electrolyte. [Copyright &y& Elsevier]

Abstract: Ecologists are interested in prediction of potential distribution of species in suitable areas, essential for planning conservation and management strategies. Unfortunately, often the only available information in such studies is the true presence of the species at few locations of the study area and the associated environmental covariates over the entire area, referred as presence-only data. We propose a Bayesian approach to estimate logistic linear regressions adapted to presence-only data through the introduction of a random approximation of the correction factor in the adjusted logistic model that allows us to overcome the need to know a priori the prevalence of the species. [Copyright &y& Elsevier]

Abstract: The corrosion behaviors of porous and dense NiTi shape memory alloys with the same nominal composition were investigated in a 0.9% aqueous NaCl solution using electrochemical methods. The study clarified the role of the porous structure in influencing the corrosion behavior of the porous NiTi alloys, which exhibited porosity values ranging from 35.5% to 63.8%. The results indicated that the porous NiTi alloy was more susceptible to localized corrosion than was the dense NiTi alloy. However, the porous NiTi alloy sample with a higher porosity did not suffer more serious corrosion than the one with a lower porosity. Furthermore, the potential distribution exists on the pore wall of the porous NiTi alloys as a result of current flow within the pore electrolyte. Thus, the role of potential distribution inside the pore and porous structure in the corrosion behavior of the porous NiTi alloys is an important factor. [Copyright &y& Elsevier]

Abstract: A modified electrode was proposed based on the sequential coating to immobilize both p-benzoquinone (BZQ) and glucose oxidase (GOD). Three electrodes, A, B, and C, were prepared separately by drop-coating the BZQ solution dissolved in different solvents on the stainless-steel/carbon (ssteel/C). Among those three electrodes, electrode B shows the best sensitivity of 2.21mAM−1 cm−2, a linear concentration range of 1.1–15mM and a response time of 100 s at a sensing potential of 0.3V. The responses of interferences, including ascorbic acid, dopamine, uric acid and acetaminophen, were ∼0%, 1.4%, ∼0% and 3%, respectively, taken the sensing current at 6.0mM glucose as 100%. In a test of the human blood sample, an error of +3.6% was noticed for electrode B. Besides, for the biofuel cell application, maximum power densities reached 18.9 and 22.5μW/cm2 at 25 and 37°C, respectively, with an all-solution-type biocathode. [Copyright &y& Elsevier]

Abstract: The bees of the Peponapis genus (Eucerini, Apidae) have a Neotropical distribution with the center of species diversity located in Mexico and are specialized in Cucurbita plants, which have many species of economic importance, such as squashes and pumpkins. Peponapis fervens is the only species of the genus known from southern South America. The Cucurbita species occurring in the same area as P. fervens include four domesticated species (C. ficifolia, C. maxima maxima, C. moschata and C. pepo) and one non-domesticated species (Cucurbita maxima andreana). It was suggested that C. m. andreana was the original pollen source to P. fervens, and this bee expanded its geographical range due to the domestication of Cucurbita. The potential geographical areas of these species were determined and compared using ecological niche modeling that was performed with the computational system openModeller and GARP with best subsets algorithm. The climatic variables obtained through modeling were compared using Cluster Analysis. Results show that the potential areas of domesticated species practically spread all over South America. The potential area of P. fervens includes the areas of C. m. andreana but reaches a larger area, where the domesticated species of Cucurbita also occur. The Cluster Analysis shows a high climatic similarity between P. fervens and C. m. andreana. Nevertheless, P. fervens presents the ability to occupy areas with wider ranges of climatic variables and to exploit resources provided by domesticated species. [Copyright &y& Elsevier]

Abstract: In this paper a free energy-based lattice Boltzmann (LB) approach for modeling and simulation of electrowetting is presented. First, based on the solution of the Poisson–Boltzmann (PB) equation, it is shown that the potential distribution inside a microsized droplet can always be assumed one-dimensional. Then, spreading and transporting of a microsized fluid droplet on a flat substrate, due to the electrowetting, are studied. By applying a voltage to the substrate, liquid–solid surface tension is locally decreased. To estimate the contact angle after applying the potential, new relations for surface tensions based on the free energy functional Minimization are proposed. The results are compared to the analytical and experimental results reported in the literature. A good agreement is found. [Copyright &y& Elsevier]

Abstract: As a factor that may affect the accuracy of the measurement of electrode potentials in proton-exchange membrane fuel cells, the potential difference in a strip of Nafion® 117 membrane induced by a humidity or temperature gradient was examined. The sample was placed in a cell with two chambers, where the temperature and humidity could be controlled individually. Hydrogen gas was fed to both chambers, and the voltage between two electrodes set at the ends of the sample, which acts as a reversible hydrogen electrode, was measured. A higher potential of the electrode was observed when humidity or temperature was set lower than the other electrode. [Copyright &y& Elsevier]

Abstract: The scanning micro-reference electrode (SMRE) technique was used to study the corrosion behavior of reinforcing steel in simulated concrete pore (SCP) solutions with different pH values. The early stage as well as the propagation of the localized corrosion of reinforcing steel in different solutions was explored. The results indicated that the potential distribution on the reinforcing steel surface changed in homeostasis and the steel remained passive in the pure simulated concrete pore solution. The solution pH had a significant effect on the localized corrosion of reinforcing steel, and the critical pH value for localized corrosion of reinforcing steel in SCP solutions was between 11.46 and 11.31. [Copyright &y& Elsevier]

Abstract: Front-gate and back-gate potential distributions and threshold voltage of recessed source/drain (ReS/D) ultrathin body (UTB) silicon-on-insulator (SOI) MOSFETs are modeled. The analytical expressions of the front-gate and the back-gate potential distributions are derived by assuming a parabolic potential variation perpendicular to channel and by solving 2D Poisson’s equation. Based on strong inversion criterion applied to the surface potential minimum value, threshold voltage model of the short channel ReS/D UTB SOI MOSFETs is derived. The model is verified by comparison with 2D numerical device simulator over a wide range of different material and geometrical parameters and very good agreement is obtained. [Copyright &y& Elsevier]

• Design profiled anodes to improve the uniformity of current distribution in the molecular-plating of actinide compounds. • A finite element model was utilized to optimize the setup of the anodes and the cell for high-quality plating layer. • Based on the simulations, the inhomogeneity of the molecular-plating actinide layer was decreased to 2.08% experimentally. A homogeneous thin film of actinide oxides on a metal substrate is very important for nuclear analysis. Compared with physical deposition methods, molecular plating attracts considerable attention because of its wide applicability, high utilization rate, and low consumption of actinide compounds. Distinct from conventional electroplating, molecular plating is generally performed in an organic solvent without additional supporting electrolyte except for dissolved actinide compounds. The potential distribution and the mass transfer processes are crucial for achieving high purity and uniform thickness. Because actinides are rare resources, it is essential to set up a theoretical model to ensure the controllable fabrication of actinide targets. For these, we design a profiled rotating electrode made using platinum-covered titanium wire (Pt-Ti) as the anode, and we simulate the potential and current distribution between the profiled Pt-Ti anode and the aluminum cathode by finite element analysis, considering factors such as the electrode shape, the rotation rate, the anode-cathode distance, etc. The theoretical model is accurate, and the wafer-scale actinide targets are fabricated with high quality and high efficiency. [ABSTRACT FROM AUTHOR]

Abstract: A new method is presented for interpreting the data collected using three-electrode configurations, working electrode (WE), counter electrode (CE), and reference electrode (RE) in solid galvanic cells. The common flat arrangement of RE coplanar with the WE, both resting on the solid electrolyte (SE) is experimentally convenient but poses difficulties in the evaluation of the results. A calibration method is presented that allows one to relate the true impedance to the measured signals. It is also shown that in the special case where the RE is placed on a thinner extension of the SE, the placement of the reference electrode side by side introduces only a negligible error. In the case when the current carrying electrodes can be made of equal size, only misaligned, the error can be corrected, to first order, by an averaging procedure, using an annular reference electrode. The configuration analyzed in detail is a 2D one with partial results also reported for a 3D configuration. [Copyright &y& Elsevier]

Abstract: By exploiting atomic-force-microscope potentiometry, we have studied the local potential distribution in the solution-processible tetrabenzoporphyrin (BP) bottom-contact thin-film transistor under controlled atmospheres. It is found that abrupt and big potential drops mainly appeared at the domain boundaries and cracks in the BP film when the transistor was under operation, indicating a dominant influence of domain boundary and crack on the device performance. Exposure of the device to O2 drastically reduced the potential drops at some boundaries, which is the main reason for the improved device performance by O2 exposure. [Copyright &y& Elsevier]

Abstract: The placement of reference electrodes in solid galvanic cells is discussed. The common flat arrangement with a reference electrode side by side on an extension of the solid electrolyte (SE) is experimentally convenient but poses difficulties in the evaluation of the results. Common interpretation of the measurement introduce an error into the impedances determined. The error may be significant. A calibration method is presented that allows to relate the true impedance to measured signals. It is also shown that in the special case where the extension in the SE can be made thinner than the SE, the placement of the reference electrode side by side introduces only a negligible error. In the case when the current carrying electrodes can be made of equal size, only misaligned, the error can be corrected, to first order, by the use of two reference electrodes and an averaging procedure. [Copyright &y& Elsevier]

Abstract: This study discusses the use of potential distribution analysis during the deposition of metal ions, at limiting current conditions and determines the optimum electrode thickness at which no hydrogen evolution occurs. The potential distribution studies were carried out on stainless-steel fibres of three different surface areas. The fibres were used as cathodic porous electrodes during the deposition of Ag(I) ions contained in 0.1 mol dm−3 KNO3 and 0.6 mol dm−3 NH4OH electrolyte. The comparison between the experimental and the theoretical potential distributions show good agreement at mean linear flow rates in the range of 0.24 and 0.94 cm s−1. [Copyright &y& Elsevier]

Abstract: The larch (Larix) genus is the most important species group in the forest ecosystems in Northeastern China, occupying about 25% of the forest areas. The high tolerance to coldness and relatively fast growth rate make this genus the main species group for forestation. According to the predictions of the global circulation model CGCM3, temperature could rise by 2–4°C over the next 100 years. Few studies have been conducted on the response of larch species to climate warming in Northeastern China. Such studies are becoming increasingly needed due to the economic and ecological significance of this genus. This paper studies the potential distribution ranges of three larch species under the current and the warming climate conditions. A new classification and regression tree technique, Random Forest, was used to investigate the potential distributions of three larch species, based on 18 environmental variables which reflect the climate, topography and soil conditions of Northeastern China. The results showed that the biological coldness index (BCI) is the most important factor for Dahurian larch, annual precipitation (AP) is the most important factor for Korean larch and elevation (DEM) is the most important factor for Prince Rupprecht larch. Under the current climate regime, in general, the prediction accuracy for the training dataset is much higher than that of testing dataset. The prediction accuracy for Dahurian larch is much higher than that of other two larch species. Under three climate warming scenarios, the southeast boundary of suitable habitat of Dahurian Larch was modeled to retreat northwestward by 90km (CGCM3-B1) via 105km (CGCM3-A1B) to 140km (CGCM3-A2) scenario. The potential area would thus decrease from 25.5millionha currently to 13, 9.5 and 7.2millionha, correspondingly. The northwest boundary of suitable habitat for Korean larch was modeled move northwestward by 100km (CGCM3-B1) via 125km (CGCM3-A1B) to 340km (CGCM3-A2), while the southern boundary may move northeastward 125km via 170–200km, respectively. The modeled potential area thus decreased from 14.6millionha to 14.5, 12.6 and 9.7millionha, correspondingly. The suitable habitat of Prince Rupprecht Larch was modeled to disappear under each of the three scenarios. [Copyright &y& Elsevier]

Abstract: Experiments were done in a new open cylindrical ICR cell to establish ion–ion collisions between positive and negative ions of SF6 in the gas phase for the first time. Only one electron pulse for ion generation was employed (single shot). The role of pressure was illustrated to encourage high ion densities to be a prerequisite for ion–ion reactions. No electron transfer could be deduced from the experiments. Anion–anion collisions could be indicated. The dynamics of applied potential changes on both ion polarities in a double well potential configuration was studied intensively. In depth analysis of radial excitation patterns of positive and negative ions trapped simultaneously in different stability regions reveals sharp discrimination in the extent of radial acceleration. SIMION simulations were done to probe several electric forces, which both positive and negative ions experience during radial excitation event. Axial component of radial dipolar excitation field was also analyzed. Distortion in radial ion trajectories during radial excitation event was indicated when both ion polarities were excited simultaneously. [Copyright &y& Elsevier]

Abstract: Several modelling species distribution studies have been developed, in last years, though mainly applied in higher plants, mammals or birds. However, little is known about overlooked taxa like lichens. We have evaluated the potential distribution of eleven threatened lichens in Spain and how the Natura 2000 network contributes to protect them. To overcome difficulties related to the lack of systematic surveys in those poorly known species we used only-presence data by means of ENFA (ecological-niche factor analysis). Then, we used ENFA to model the environmental niche of each species and to obtain the habitat suitability maps. In order to test the effectiveness of the Natura 2000 network, the habitat high suitability map for all species was overlapped with the network map. Our results show that all species considered present habitats requirements different from the average conditions of Spain, although clear differences exist among the species. That is, Peltigera elisabethae shows an extremely narrow niche, whereas Peltigera neckeri presents the highest ecological breadth. High temperature and long drought periods are the variables which restrict more the occurrence of these species. So, all species appear mainly confined to well-conserved forest and mountain ranges where these variables are dimmed. This mainly occurs in the oceanic northern fringe and in the higher Mediterranean mountains. In relation to the success of the Natura 2000 network, our results show that the capability of this network to protect key habitats for these species seem to be guarantied, probably because most reserves appear in mountainous areas in Spain. Evaluation of reserve network effectiveness needs the use of this type of gap analysis and especially the inclusion of ‘not charismatic’ organisms such as lichens. [Copyright &y& Elsevier]

Abstract: A mechanism of local lowering of the Schottky barrier height (SBH) is proposed, which causes nonideality in nearly ideal Au/n-Si and Au/n-GaAs Schottky barriers. Positively ionized defects generated by the process very close to the interface induce electrons in the metal-induced gap states (MIGS) and lower the SBH locally. The spatial density distribution of the ionized defects obtained from the SBH distribution is determined by the unique interaction with the MIGS. The defects are considered to have the negative-U property and are neutralized at very close positions to the MIGS. The potential distributions close to the interface have a considerable potential drop due to the large defect density. These inhomogeneous potentials are coincident with the energy level scheme of the defect identified as the defect causing the nonideality. This defect is Si self-interstitial in Au/Si SB, and As antisite in Au/n-GaAs SB. This MIGS with process-induced defect model supersedes the previously proposed two major Fermi level pinning models. The mystery of the T 0 effect is solved. The thermionic-field emission current taking place in the strong electric field has influence on the I–V characteristics at low temperatures. Regarding the C–V characteristics of Au/Si SB, the observed extra capacitance under the forward bias is an experimental evidence in accordance with the proposed model. [Copyright &y& Elsevier]

Abstract: We show that linearized Poisson–Boltzmann approximation for the calculation of potential distribution in electrochemical nano-gap is good for qualitative estimates needed to describe their current–voltage characteristics. The nonlinearity of response is to a high degree compensated by various effects of ion exclusion from the gap. [Copyright &y& Elsevier]

Abstract: Because the field of a uniformly charged circular arc involves elliptic integrals, not generally possessing symmetry of a uniformly charged ring, it is difficult to solve and discuss this problem. This paper investigates the problem and presents the potential function and the field function of a uniformly charged circular arc together with discussions about them by using the theory of elliptic integrals and the analytic method. [Copyright &y& Elsevier]

Abstract: The adsorption of ions at the interface between two immiscible electrolyte solutions (ITIES) is primarily controlled by the potential distribution across the interface, which in turn is influenced by the adsorption process. In the present paper, we simulate the effect of the adsorption of charged species on the charge distribution at the ITIES based on the classical description of the interface employing the Gouy–Chapman model. The inner layer is considered as a charged plane, where the ionic adsorption takes place. The potential at this plane is determined by the electro-neutrality condition. Various adsorption isotherms are considered, including potential dependent isotherms based on the Langmuir and Frumkin adsorption models. The potential distribution and the charge density profile are derived by solving the Poisson–Boltzman equation numerically. We show that the charge distribution in the interfacial region is significantly affected by the adsorption of ionic species. Under certain conditions, the adsorption results in a non-monotonic potential distribution with a potential trap at the interface. [Copyright &y& Elsevier]

Abstract: The formation of micro-droplets, 1–10μm in diameter, were observed around the edge of main-droplet formed by the deliquescence of salt particles deposited on metals in atmosphere. The characteristics of the formation of micro-droplets were studied in a humidity-controlled chamber. The results showed that oxygen and relative humidity were the key variables for the formation of micro-droplets. Meanwhile, micro-droplets could only appear on the electropositive areas of metal surface based on the potential distributions with the scanning Kelvin probe. The electrochemical polarization results proved that the current established by the potential difference between the central and peripheral area of main-droplet was the true driving force for the formation of micro-droplets. [Copyright &y& Elsevier]

Predicting distribution patterns of invasive species in regions outside of their native range is a fundamental component of early warning systems. The first aim of this study was to analyse some of the constraints and limitations concerning the applicability of results obtained from predictive, eco-geographical modelling methods. The next main objective was to evaluate the minimum monitoring-time requirements for reliable range predictions based on non-indigenous occurrences. This was achieved by comparing departures in ‘model quality improvement’ with ‘elapsed time’ after initial species establishment and subsequently increasing levels of data completeness.Incomplete sampling or small population numbers are common problems when dealing with recently established non-indigenous species. To account for this, this study compared results from two recently developed methods which are supposedly able to deal with the ‘few known occurrences’ factor when predicting potential geographical distributions.Time series re-sampling was used as an historical simulation approach in order to apply a more realistic scenario of data situations typical for early stages of invasion processes. The well-documented invasion history of Purple loosestrife (Lythrum salicaria L.) in North America has provided an appropriate case study which highlights the effects of varying spatio-temporal trends, in terms of predictability of the currently invaded range. The results of both methods congruently showed that it would be unreasonable to predict the potential distribution of this species, to any acceptable degree of accuracy, on the base of the first few recorded data points.Based on a realistic scenario of spatial invasive spread, a reliable prediction of the current non-native distribution in North America was only possible after an elapsed time span of approximately 150 years. Even a prediction precision of only 50% of the current occurrences would require at least 100 years after naturalization. Generally, the predictive capacities of correlative models are conspicuously decreased when underestimated niche dimensions are included—irrespective of the used method. As invasive spread is irreversible in most cases, monitoring time requirements of 100–150 years have to be regarded hazardous and unacceptable. Consequently, large scale spatial predictions cannot rely on the analysis of currently known non-indigenous occurrences alone. One suggestion, therefore, may be to incorporate species’ ‘native range distribution’ data into the models in order to achieve more reliable spatial predictions over a shorter timescale. [Copyright &y& Elsevier]

We have proposed a mechanism of the local Schottky barrier height (SBH) lowering to explain the nonideal characteristics in Si SBs. Positively charged defects close to the M/S interface induce image charge in the metal-induced gap states (MIGS) and lower the SBH. Based on this mechanism, the inhomogeneous potential distributions in the proximity of the MIGS are calculated in agreement with the I–V characteristics. The energy level of the defect, identified with Si self-interstitial, is in agreement with the theoretical value. The energy width of the defect is nearly equal to the standard deviation in the Gaussian distribution describing the SBH inhomogeneity. Thus, the propriety of the model is confirmed. [Copyright &y& Elsevier]

The spatial distribution of Zn2+ during galvanic corrosion of a model Zn/steel couple in 0.01 M NaCl was investigated using a scanning zinc disk electrode. The couple had a coplanar arrangement of a steel substrate with an electroplated zinc layer at the center. During galvanic corrosion, the marked changes in the Zn2+ concentration were confined to a thin solution layer ca. 1.0 mm thick above the couple surface. In this thin solution layer above the zinc layer, a higher concentration region of Zn2+ in the range of 5–18 mM extended around the zinc layer in the solution during galvanic corrosion. Conversely, above the steel surface distant from the zinc layer, the surface concentration of Zn2+ was almost zero during galvanic corrosion. On this surface, the precipitation of zinc corrosion products due to the hydrolysis reaction of Zn2+ was observed. The distribution of the Zn2+ concentration supported that Zn2+ acted as a buffer that suppressed the increased pH due to the cathodic reaction on the steel surface near the zinc layer and almost no corrosion products formed there. The spatial distribution of Zn2+ is discussed in relation to the distributions of potential and pH and the surface morphology of the galvanic couple. [Copyright &y& Elsevier]

The spatial distribution of pH during galvanic corrosion of a model Zn/steel couple immersed in 0.01 M NaCl was investigated using a scanning tungsten pH electrode. The couple consisted of a steel substrate with a 3 μm-thick layer of zinc electroplated at its center. During galvanic corrosion, marked changes in pH occurred, which were confined to a thin layer of solution ca. 1.5 mm over the couple surface. As the surface was approached, the pH over the zinc layer decreased slightly from ca. 5.6 in the original bulk solution, while the pH over the steel surface distant from the zinc layer increased to ca. 11.5. The area of low pH extended not only over the zinc layer, but also over the steel surface adjacent to the zinc. Zinc corrosion products precipitated in the region of high pH. The pH distribution arising from the galvanic corrosion of the couple is discussed in terms of the potential distribution and the morphology of the precipitated zinc corrosion products. [Copyright &y& Elsevier]

Obtaining the distribution of the voltage and temperature of the punch–die–compact systems in the spark sintering process is useful for generalization of its process control. The temperatures of these systems using two kinds of powders, titanium and alumina, of a conductor and an insulator, respectively, are measured by thermocouples in the constant current discharging process. The steady state showing the constant values of temperature and relative density is achieved in this process, and the measured temperature distribution in the systems is changed depending on the kind of compacts. The voltage and temperature of the systems at the steady state are also calculated on the basis of Ohm’s and Fourier’s laws. The calculated voltage distribution or current flow in the punch and die for the titanium compact system is similar to that for the alumina compact system, although there is the minor difference of the voltage distribution between titanium and alumina compacts because of the difference in the specific resistivity of compacts. The calculated temperature distribution is changed in these systems depending on the kind of compacts, because of the difference in the amount of Joule’s heat of compacts, which agrees with the temperature distribution measured by thermocouples. It is found from the result obtained in this study that distributions in voltage and temperature can be estimated by this calculation method, regardless of a kind and shape of the punches, dies and compacts. [Copyright &y& Elsevier]

Potential, ionized impurity, and free carrier distributions are investigated for Schottky junction under a reverse bias with an alternating component which is large compared to kBT/q. Nonlinear effects in the junction behavior are considered in the framework of a general large signal model as well as is in the framework of a second-order model. Free carrier distribution is assumed to be an equilibrium one and impurity ionization is treated using Shockley–Read–Hall statistics. It is shown that in the large-signal case potential, ionized impurity, and free carrier distributions are significantly different from the corresponding small-signal distributions. The proposed second-order model is shown to be accurate for the values of the fundamental of ac potential which are less or approximately equal to kBT/q. [Copyright &y& Elsevier]

The effect of the applied potential across a biomimetic model membrane, Δφ, on the extent of dissociation of surface bound ionizable groups has been examined theoretically using a formalism that shares common features with that recently introduced by White and coworkers (Langmuir 9 (1993) 1) to account for the occurrence of peaks in the cyclic voltammetry of self-assembled monolayers rigidly attached to an electrode surface, bearing the same type of ionizable groups facing the electrolyte. Numerical solutions of the governing coupled, highly non-linear system of equations yielded for reasonable membrane parameters, and under conditions of physiological relevance, linear changes in the extent of ionization as a function of Δφ, about Δφ=0, of ca. 0.07 units/V. Also considered in this work was a more general situation in which the contributions to the total interfacial capacity, CT, due to the diffuse double layers, CSj, and to the fixed charges Cj(fj) on each of the sides of the membrane-like assembly denoted by ‘j’, were comparable in magnitude to the potential independent capacity of the intervening hydrophobic layer, i.e. low-electrolyte concentration. In such case, plots of CT versus Δφ displayed a global minimum at Δφ=0 and two local maxima at values of Δφ slightly negative and positive to the maxima observed in the corresponding Cj(fj) versus Δφ plots. Implications of the results obtained to excitable bilayer membranes are briefly discussed. [Copyright &y& Elsevier]

We have proposed a mechanism of nonideality in nearly ideal Au/n-Si Schottky barriers (SBs), which explains various experimental observations called the To anomaly. Because of the nature of the metal-induced gap states (MIGS), positively ionized defects induced by the process very close to the interface are considered to cause local lowering of the Schottky barrier height (SBH) due to filling-up of the MIGS. The formulation of the defect density is revised to be consistent with the experimental observations. There is a potential drop of more than 100 mV at about 20 A˚ from the interface due to the space–charge of the defects. The saddle potential for the low-SBH spot is lowered by this potential drop. Therefore, the local SBH lowering is observable in the I–V characteristics. [Copyright &y& Elsevier]

Obtaining the distribution of the voltage and temperature of the punch–die–compact systems in the spark sintering process is useful for generalization of its process control. The temperatures of these systems using two kinds of powders, titanium and alumina, of a conductor and an insulator, respectively, are measured by thermocouples in the constant current discharging process. The steady state showing the constant values of temperature and relative density is achieved in this process, and the measured temperature distribution in the systems is changed depending on the kind of compacts. The voltage and temperature of the systems at the steady state are also calculated on the basis of Ohm’s and Fourier’s laws. The calculated voltage distribution or current flow in the punch and die for the titanium compact system is similar to that for the alumina compact system, although there is the minor difference of the voltage distribution between titanium and alumina compacts because of the difference in the specific resistivity of compacts. The calculated temperature distribution is changed in these systems depending on the kind of compacts, because of the difference in the amount of Joule’s heat of compacts, which agrees with the temperature distribution measured by thermocouples. It is found from the result obtained in this study that distributions in voltage and temperature can be estimated by this calculation method, regardless of a kind and shape of the punches, dies and compacts. [Copyright &y& Elsevier]

Electrochemical promotion (EP) of gas-phase catalysis with O2−-conducting solid electrolytes is addressed. The behavior of the reference electrode, prepared by deposition of a gold film, was found to be quasi-reversible, 1/2O2/O2− being the potential determining redox couple. A fairly symmetrical potential distribution in the electrochemical cell was calculated. The IR drop correction was shown to be negligible at low currents typical to EP experiments. The electrochemical activation of catalysis is due to the act of promoters at the catalyst &z.sfnc; gas interface. A model is proposed to describe catalytic reaction rate transients assuming free surface site dependent formation, rapid spreading-out and first order rate consumption of O2− promoters. The model predicts exponential catalytic rate transients with current dependent polarization and current independent relaxation behavior. It enables determination of the maximum limiting value of the Faradaic efficiency, being a current independent property of the catalytic system. The validity of the model is confirmed for anodic galvanostatic EP of ethylene combustion over IrO2/YSZ catalyst. [Copyright &y& Elsevier]

Insects are highly involved in accidental introductions in non-native areas. Potential distribution modelling is routinely used to predict the dynamics of such range expansions, giving insights on which areas are climatically suitable for establishment. However, even in areas where climatic conditions are unsuitable, colonization may be still possible in sub-areas with particular, human activity-driven microclimates, such as cities. We used as a model species the Asian mud-dauber wasp Sceliphron curvatum (Hymenoptera: Sphecidae), which arrived in Europe 40 years ago, to show that cities may be used by alien species to enlarge their distribution into climatically non-optimal areas. By using an average consensus from six different models, we predicted that, based on climate, S. curvatum would find the highest suitability in most part of Mediterranean basin, which are characterized by high summer temperatures and reduced climatic oscillations. The species is indeed often observed in such areas, but also in Central Europe, where suitability is overall lower. At such latitudes, however, the wasp was more often found in cities (which have the highest suitability) than in peri-urban and rural areas, possibly according to the urban 'heat island' effect. In Southern Europe, where climate is overall more favourable for the species, suitability tended to be more similar in both urban and rural environments, and urban detections were indeed rarer. The inclusion of population density in the model improved the suitability of Northern areas in an expected urbanization-driven jeopardized pattern. Hence, S. curvatum would be able to colonize in the future at least some climatically unsuitable Northern areas, reaching up to 70° latitude, by using cities as the main sites for establishment. [Display omitted] • Sceliphron curvatum finds high climatic suitability in the Mediterranean basin. • In Central Europe suitability is lower but the wasp is often observed in urban areas. • Urban areas have high climatic suitability especially in Central Europe. • Including population density in the model improved the suitability of Northern areas. [ABSTRACT FROM AUTHOR]

Date palm (Phoenix dactylifera L.), a member of the Arecaceae family is grown on large areas in the world with varying climatic and soil conditions. However, date palm productivity is severely being affected by ongoing climate changes. Identifying suitable production areas for date palm under changing climatic conditions could help to sustain its production. The objective of the current study was to predict the range expansion/contraction in the production areas of date palm in a semi-arid region. CLIMEX model was used to estimate the expected expansion/contraction in the potential distribution areas of date palm under current and future climatic conditions. Two climate change scenarios [(CCSs) i.e., A1B and A2] were used and production suitability was predicted for three timespans [i.e., 2030 (early-century), 2050 (mid-century) and 2100 (late century)]. The model estimated significant suitable area (71.21%) for date palm cultivation under current climatic conditions. Climate change seemed to have no impact on production areas until early-century. However, range contraction (8 and 10% decline under A1B and A2 scenarios, respectively) in the suitable areas was predicted for mid-century. Nonetheless, severe range contraction (27.98 and 33% decline under A1B and A2 scenarios, respectively) was predicted in the production areas for late-century. Most of the climatically suitable areas during early-century became unsuitable during late-century. Moreover, the model predicted northward shift in the production areas for date palm. The range contraction was higher under A2 climate change scenario due to higher warming trend compared to A1B scenario. The results of the current study indicate that plenty of areas are suitable for date palm cultivation. Thus, date palm cultivation could be increased in these areas for augmenting the production. Climate warming will result in the range shifts; thus, cultivation of future orchards should be planned in the most suitable areas in order to avoid the negative consequences of climate change on date palm production in the country. [ABSTRACT FROM AUTHOR]

Ecological niche modelling is used in deep-sea research to investigate the environmental preferences and potential distribution of data-poor species. We present a mesoscale assessment of Mediterranean seascape suitability for the cold-water coral Lophelia pertusa (= Desmophyllum pertusum , Linnaeus, 1758). We estimated seascape suitability and uncertainty maps using an ensemble approach of three machine-learning algorithms (Generalized Boosting Model, Random Forest, Maximum Entropy) based on environmental predictors. Bathymetry, bathymetric slope and pH were the most important predictors for the models. Overall the models reached good to excellent performance, with a very reliable prediction of the most suitable areas. In the Mediterranean Sea, L. pertusa encounters environmental settings close to its physiological limits but, despite the highly variable quality of the Mediterranean seascape, we identified high suitability areas mostly along the upper slope and at submarine canyons of the Western and Central margins. The existing MPAs do not overlap with high suitability areas, and therefore L. pertusa is only protected at the deepest fringe of its potential distribution by the implementation of the bottom trawling exclusion beyond 1000 m depth. This seascape suitability assessment may assist future research, including high-resolution modelling targeting high-suitability areas, investigation on the resilience of L. pertusa populations and development of conservation actions. • We mapped the potential distribution of Lophelia pertusa in the Mediterranean Sea. • We provide uncertainty estimates for the model predictions. • Mediterranean colonies are subjected to challenging environmental conditions. • The most suitable areas occur in the continental slope of the west and central basins. • The overlap of the Mediterranean MPAs with the most suitable areas is limited. [ABSTRACT FROM AUTHOR]

[Display omitted] • The potential gradients on bipolar electrodes were investigated. • Bipolar anodization of aluminum was conducted in a direct current electric field. • Anodic films with structural gradients were formed on the unconnected aluminum. • The area of the anodic reaction was much larger than expected. In this study, the electrical potential distributions on aluminum bipolar electrodes (BPEs) subjected to bipolar anodization in a direct current (DC) electric field were investigated. Aluminum sheets were used as BPEs, suspended in an electrolyte solution, and positioned either vertically or horizontally at the center of a cell. The results of reflective interference measurements, depth-profiling analysis, and re-anodization clearly revealed that the thicknesses of the porous alumina films and barrier layers near the aluminum substrates can be taken to represent the potential distributions on the horizontally located BPEs; the thickest anodic alumina was formed at the edge of the anodic pole of the BPE, and its thickness continuously decreased in the direction of the cathodic pole. Furthermore, the area of the anodic reaction was much larger than expected, accounting for 90% of the BPE. [ABSTRACT FROM AUTHOR]

• Pulse current make the potential distribution of concrete more uniform compared to direct current. • Increasing current density will increase the total concrete desalination efficiency. • Total concrete resistance increases during ECR process. • Pulse current repair is a suitable method to improve the efficiency of chloride removal. Electrochemical chloride removal (ECR) technique as an effective repair method has been applied to chloride-attacked concrete structures. This research studies the influence of different external electrical fields on the ECR treatment for reinforced concrete. Two types of electrical fields including direct and pulse current with average current densities of 2, 3 and 4 A/m2 were investigated. The chloride ion content of concrete before and after ECR treatment was determined. The results show that no matter what current density was used for concrete repair, the effect of pulse current on the desalination of concrete was better than direct current. Also, increasing the current density can also promote the concrete chloride removal efficiency. When applying a current density of 4 A/m2 to the steel rebars for 28 days, the remained chloride concentration of the concrete after ECR treatment was obviously lower than that of using 2 and 3 A/m2. In addition, the half-cell potential method was used to evaluate the rebar potential distribution. It was found that the pulse current can make the cathode reinforcement arranged in parallel in the concrete have a more uniform potential distribution, which indicates that the applied electrical current is easier to uniformly pass through the whole concrete structures. [ABSTRACT FROM AUTHOR]

• Ensemble species distribution modelling was done for freshwater fish. • Occurrence records of small freshwater fish Amblypharyngodon mola were used. • Climatic, topographic, landcover and soil variables were used as predictors. • Upstream precipitation, soil pH and elevation were found to be the key indicators. • Ganges delta region was found to be most suitable habitat. The key challenge in the fields of conservation and resource management is to track local, regional and global species extinctions and preserve biodiversity through optimization of investment of funds. To fulfil that purpose modelling and mapping habitat suitability of species is becoming essential. The freshwater ecosystem is today one of the most threatened ecosystems and fishes are especially vulnerable for climate change as they have fewer choices for dispersal. The altered thermal regimes, land use and hydrology together cause isolation, fragmentation and changes in distributional patterns of fish. In such landlocked situation, there is utmost need to identify suitable environmental conditions for a species to exist. Indigenous fish is one of the essential components of healthy inland aquatic ecosystems as they fulfil several important ecological functions and form an important part of the aquatic food web. Amblypharyngodon mola is an economically and ecologically important indigenous freshwater fish species of the tropical and subtropical floodplain rivers and wetland habitats of India and Bangladesh. However, lack of knowledge about the key environmental indicators is hindering appropriate management and conservation initiation. Modelling and mapping the distribution of A. mola was done for identifying the key environmental variables and predicting the potential distribution area of the species in current climatic condition. The species occurrence data were accessed from both primary and secondary sources and used after cleaning and removing biasness. Climatic, topographic, landcover and soil variables of 1 km resolution were used as environmental predictors. India and Bangladesh together were used as model background. Ensemble species distribution modelling was done, and the model was validated by area under the curve (AUC) value (>0.7). The result showed that the Ganges delta of lower reach going through West Bengal and Bangladesh is most suitable for A. mola occurrence. Annual upstream precipitation (hydroclim_12), soil pH in water (soil_average_02) and elevation (ele_01) are the key indicators for predicting the habitats suggesting the importance of hydroclimatic, topographic and soil variables in determining the distribution of the fish. [ABSTRACT FROM AUTHOR]