Immunity of electronic and transport properties of phosphorene nanoribbons to edge defects

We present an extensive study of the electronic properties and carrier transport in phosphorene nanoribbons (PNRs) with edge defects by using rigorous atomistic quantum transport simulations. This study reports on the size- and defect-dependent scaling laws governing the transport gap, and the mean free path and carrier mobility in the PNRs of interest for future nanoelectronics applications. Our results indicate that PNRs with armchair edges (aPNRs) are more immune to defects than zig-zag PNRs (zPNRs), while both PNR types exhibit superior immunity to defects relative to graphene nanoribbons (GNRs). An investigation of the mean free path demonstrated that even in the case of a low defect density the transport in PNRs is diffusive, and the carrier mobility remains a meaningful transport parameter even in ultra-small PNRs. We found that the electron–hole mobility asymmetry (present in large-area phosphorene) is retained only in zPNRs for W > 4 nm, while in other cases the asymmetry is smoothed out by edge defect scattering. Furthermore, we showed that aPNRs outperform both zPNRs and GNRs in terms of carrier mobility, and that PNRs generally offer a superior mobility-bandgap trade-off, relative to GNRs and monolayer MoS₂. This work identifies PNRs as a promising material for the extremely scaled transistor channels in future post-silicon electronic technology, and presents a persuasive argument for experimental work on nanostructured phosphorene.

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High Enthalpy Geothermal Potential of the Deep Gas Fields in Central Drava Basin,Croatia

In Croatia there is an urgent need to improve energy balance with more efficient methods of energy resources exploitation. There are approximately 3,000 wells drilled on oil, gas/condensate and geothermal reservoirs, of which only 50 were primarily drilled for purpose of geothermal exploitation. Over 10,000 seismic measurements were conducted. The most of drilled wells are scheduled for permanent abandonment in the near future, because of economical reasons and technological limitations of production. However, oil and gas wells which are near the end of production might be reassigned into geothermal wells, if aquifer water temperature and flow were satisfactory.     

Representing soil pollution by heavy metals using continuous limitation scores

The paper suggests a methodology to represent overall soil pollution in a sampled area using continuous limitation scores. The interpolated heavy metal concentrations are first transformed to limitation scores using the exponential transfer function determined by using two threshold values: permissible concentration (0 limitation points) and seriously polluted soil (4 limitation points). The limitation scores can then be summed to produce the map of cumulative limitation scores and visualize the most critically polluted areas. The methodology was illustrated using the 784 soil samples analyzed for Cd, Cr, Cu, Ni, Pb and Zn in the central region of Croatia. The samples were taken at 1×1 and grids and at fixed depths of 20 cm. Heavy metal concentrations in soil were determined by ICP-OES after microwave assisted aqua regia digestion. The sampled concentrations were interpolated using block regression-kriging with geology and land cover maps, terrain parameters and industrialization parameters as auxiliary predictors. The results showed that the best auxiliary predictors are geological map, ground water depth, NDVI and slope map and distance to urban areas. The spatial prediction was satisfactory for Cd, Ni, Pb and Zn, and somewhat less satisfactory for Cu and Cr. The final map of cumulative limitation scores showed that 33.5% of the total area is suitable for organic agriculture and 7.2% of the total area is seriously polluted by one or more heavy metals. This procedure can be used to assess suitability of soils for agricultural production and as a basis for possible legal commitments to maintain the soil quality.     

Comparative analysis of the organisational learning process in Slovenia, Croatia, and Malaysia

Several empirical studies have proved that better organisational learning induces higher organisational performance. However, none of them addressed the issue of organisational learning process simultaneously in several countries. In our contribution, we aim to test differences in the way companies learn in Slovenia, Croatia, and Malaysia. We used the OLIMP questionnaire, a measurement instrument developed and tested by [Dimovski, V. (1994), Organisational learning and competitive advantage. PhD Thesis, Cleveland, Ohio; Dimovski, V., & Škerlavaj, M. (2005). Performance effects of organisational learning in a transitional economy. Problems and Perspectives in Management 3(4), 56–67]. It employs three measurement variables (information acquisition, information interpretation, and behavioural and cognitive changes) as well as 38 items (presented in the paper) to measure the organisational learning construct. In autumn 2005 data from 203 Slovenian, 202 Croatian and 300 Malaysian companies were gathered. The results indicate that companies in all three countries under scrutiny are closest in terms of behavioural and cognitive changes, meaning that globalisation and other challenges of the modern business environment demand all of them to change and adapt quickly. However, the ways they are coping with these challenges are different. There are more similarities than dissimilarities between Slovenia and Croatia, while this is not the case when comparing both countries to Malaysia. When acquiring information, Slovenian and Croatian companies rely more on internal sources (own employees, past decisions, etc.), while Malaysian companies tend to rely more on external sources and more often have employees dedicated to searching for external information. When trying to interpret the information acquired, Slovenian and Croatian companies rely more on personal contacts, informal team meetings and believe that information given to subordinates must be simple and concise, while Malaysian companies tend to use more formal collective decision-making and written communication to understand the meaning of information.     

Dietary fibre intake in eastern Croatia as determined by an enzymatic-gravimetric method in duplicated portions

The aim of this study was to estimate the intake of dietary fibre (DF) in an urban adult sample in eastern Croatia. Forty five people (28 women and 17 men) took part in the investigation based on duplicate diet study. An enzymatic-gravimetric method was used to determine the content of total, as well as soluble and insoluble DF in duplicated portions. The mean total dietary fibre (TDF) intake for all subjects was 30.0 g/day, which is quite adequate with regard to recommendations and intakes reported from other countries. A relationship of DF intake with certain physical and socio-economic parameters (age, body mass index, education level, income per household member) of those taking part was examined. TDF intake was also found to be significantly influenced by season in this group of people, as the mean intake for the summer period was 21% higher than the winter period.     

Contrasts between organic participation in apatite biomineralization in brachiopod shell and vertebrate bone identified by nuclear magnetic resonance spectroscopy

Unusually for invertebrates, linguliform brachiopods employ calcium phosphate mineral in hard tissue formation, in common with the evolutionarily distant vertebrates. Using solid-state nuclear magnetic resonance spectroscopy (SSNMR) and X-ray powder diffraction, we compare the organic constitution, crystallinity and organic matrix–mineral interface of phosphatic brachiopod shells with those of vertebrate bone. In particular, the organic–mineral interfaces crucial for the stability and properties of biomineral were probed with SSNMR rotational echo double resonance (REDOR). Lingula anatina and Discinisca tenuis shell materials yield strikingly dissimilar SSNMR spectra, arguing for quite different organic constitutions. However, their fluoroapatite-like mineral is highly crystalline, unlike the poorly ordered hydroxyapatite of bone. Neither shell material shows ¹³C{³¹P} REDOR effects, excluding strong physico-chemical interactions between mineral and organic matrix, unlike bone in which glycosaminoglycans and proteins are composited with mineral at sub-nanometre length scales. Differences between organic matrix of shell material from L. anatina and D. tenuis, and bone reflect evolutionary pressures from contrasting habitats and structural purposes. The absence of organic–mineral intermolecular associations in brachiopod shell argues that biomineralization follows different mechanistic pathways to bone; their details hold clues to the molecular structural evolution of phosphatic biominerals, and may provide insights into novel composite design.     

Color reproduction on varnished cardboard packaging by using lower ink coverages due to the gray component replacement image processing

Even in these challenging times, cardboard packaging industry is increasing its revenue with stable annual increase prediction, but customers are increasing demands on the packaging with respect to environmental protection, attractiveness, and branding. This article aims to determine the influence of image processing in terms of gray component replacement and overprint varnishing on the color reproduction on a cardboard packaging material. A test chart with tertiary colors was defined and modified by different gray component replacement levels. It was printed in accordance with ISO norm on coated and uncoated cardboard and finished by overprinting water based, offset, and UV varnish. The prepared samples were evaluated by measuring surface coverage, tone value increase (dot gain) of primary colors and calculating ΔE₀₀ of defined tertiary colors. The results showed that gray component replacement application reduces ink consumption. Higher gray component replacement applied results in lower ink surface coverage, but the decrease is also dependent on the image content. The TVI (dot gain) is significantly influenced only by applying UV varnish, resulting with higher TVI. The color differences of the tertiary colors showed that increased level of the gray component replacement applied did not cause significant color differences, even decreased color difference in some cases. Additionally, applying gray component replacement decreased color differences in “reddish” part of the gamut. This research proved that lowering the ink consumption due to the gray component replacement will not cause significant differences in the color reproduction. Furthermore, varnishing with commercial offset or water-based varnish will not cause higher deviations in color reproduction, but use of the UV varnish would.     

Droplet Size Distribution Obtained by Atomization with Two‐Fluid Nozzles in a Spray Dryer

The possibility of predicting the droplet size distribution from the particle size distribution was investigated. For that purpose, suspensions of different types of materials were dried in a laboratory‐scale spray drier. Drying of suspensions was performed with different sizes of two‐fluid nozzles. Droplet size distribution was evaluated from the data obtained for spray drying of bismuth molybdate suspension. The method was validated experimentally with other tested materials. Investigated systems involve processes of drying, crystallization, and coating. The proposed methodology can be applied when nonagglomerated particles, spherical particles, or spherical agglomerates were obtained by spray drying.     

A fast closed-loop process dynamics characterization

Stable, integrating and unstable processes, including dead-time, are analyzed in the loop with a known PI/PID controller. The ultimate gain and frequency of an unknown process G_p(s), and the angle of tangent to the Nyquist curve G_p(iω) at the ultimate frequency, are determined from the estimated Laplace transform of the set-point step response of amplitude r₀. Gain G_p(0) is determined from the measurements of the control variable and known r₀. These estimates define a control relevant model G_m(s), making possible the use of the previously determined and memorized look-up tables to obtain PID controller guaranteeing desired maximum sensitivity and desired sensitivity to measurement noise. Simulation and experimental results, from a laboratory thermal plant, are used to demonstrate the effectiveness and merits of the proposed method.