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The development of efficient analytical procedures for the selective detection of magnesium is an important analytical task, since this element is one of the most abundant metals in cells and plays an essential role in a plenty of cellular processes. Magnesium misbalance has been related to several pathologies and diseases both in plants and animals, as far as in humans, but the number of suitable methods for magnesium detection especially in life sample and biological environments is scarce. Chemical sensors, due to their high reliability, simplicity of handling and instrumentation, fast and real-time in situ and on site analysis are promising candidates for magnesium analysis and represent an attractive alternative to the standard instrumental methods. Here the recent achievements in the development of chemical sensors for magnesium ions detection over the last decade are reviewed. The working principles and the main types of sensors applied are described. Focus is placed on the optical sensors and multisensory systems applications for magnesium assessment in different media. Further, a critical outlook on the employment of multisensory approach in comparison to single selective sensors application in biological samples is presented.

While UHI mitigation potential of cool roofs has been deeply investigated compared to cool facades, still not sufficient research effort has been dedicated to quantify the benefits of combined cool building products. The present work evaluates the thermal performance of an innovative cool roofing membrane and a cool facade painting applied on a prototype building. Moreover, an analytical procedure able to predict the cool coating thermal performance is elaborated. Such methodology can be used to determine the passive cooling potential of each product as a separate envelope component and as a combination. To this twofold aim, a preliminary in-field monitoring is developed. Therefore, a sensitivity analysis is performed to evaluate the separate and combined passive cooling contributions of the roof and the differently oriented facades. Finally, the analytical procedure is developed to define external surface temperature profiles able to predict the building coating thermal performance by minimizing the number of temperature measurements. Results show the major contribution of cool roof membrane in reducing indoor operative temperature. Nevertheless, a non-negligible cooling effect in terms of outdoor surface temperature is imputable to the South cool facade. Moreover, the analytical model shows an acceptable accuracy in representing the behavior of the building coating.

Resin-based composites are commonly used restorative materials in dentistry. Such tooth-colored restorations can adhere to the dental tissues. One drawback is that the polymerization shrinkage and induced stresses during the curing procedure is an inherent property of resin composite materials that might impair their performance. This review focuses on the significant developments of laboratory tools in the measurement of polymerization shrinkage and stresses of dental resin-based materials during polymerization. An electronic search of publications from January 1977 to July 2016 was made using ScienceDirect, PubMed, Medline, and Google Scholar databases. The search included only English-language articles. Only studies that performed laboratory methods to evaluate the amount of the polymerization shrinkage and/or stresses of dental resin-based materials during polymerization were selected. The results indicated that various techniques have been introduced with different mechanical/physical bases. Besides, there are factors that may contribute the differences between the various methods in measuring the amount of shrinkages and stresses of resin composites. The search for an ideal and standard apparatus for measuring shrinkage stress and volumetric polymerization shrinkage of resin-based materials in dentistry is still required. Researchers and clinicians must be aware of differences between analytical methods to make proper interpretation and indications of each technique relevant to a clinical situation.

The Strain Energy Density (SED) fatigue criterion is based on a material control radius. The value of this length is therefore required for an accurate assessment of the fatigue strength of any, especially severely, notched components. The singularity-based control radius is initially obtained by considering the hypothetical perfectly sharp V-notched specimen. The effect of the notch radius on the inverse search is then investigated with numerical simulations, and a new analytical procedure is introduced for the determination of the (actual) control radius. This procedure is applied to the experimental data of three metal alloys with different load ratios and manufacturing conditions.

This study focused on improving the design of slender structures with reinforced concrete (RC) telecommunication towers as the main application. Analytical procedure based on Rayleigh’s method to compute the first natural vibration frequency and the critical buckling load was development. All the nonlinearities present in the system were considered, in addition to the soil-structure interaction and the variation of the geometric properties along the length of the structure. The geometric nonlinearity and imperfections of the tower structure were computed as functions of the axial load using a geometric stiffness matrix. Further, the material nonlinearity was accounted for by reducing the flexural stiffness. As concrete structures exhibit viscoelasticity, creep was calculated using the Eurocode 2 model. The soil-structure interaction was modeled as a set of distributed springs. To validate the proposed method, the first frequency and critical buckling load were compared with those yielded by FEM simulations. The frequency results were in good agreement with those of the FEM simulations, indicating that the proposed method is sufficiently accurate for use in engineering design applications and easy to implement. On the other hand, the buckling load results obtained using the proposed method and FEM differed significantly, motivating further investigation.

Knowledge of the in situ stress state of rock mass is fundamental for engineering, geological and geophysical applications. In situ stress state determination requires in principle the evaluation of the three principal stresses and the related principal directions, but it is widely recognized in the literature that the maximum horizontal stress is the most difficult component to accurately estimate. In the context of borehole methods, this paper proposes a step-by-step analytical procedure to estimate some bounds to the maximum horizontal stress, starting from a geomechanical description of the rock and relying on information generally available in the engineering practice. The procedure is divided in substeps, each one requiring additional information about the mechanical properties of the rock and on the geometrical properties of the failed portion of rock: more information available implies a lower uncertainty on in situ stress estimate. Furthermore, since the proposed procedure is analytical, it allows a complete and very easy implementation in a spreadsheet. The aim of the work is thus to provide a rigourous but simple analytical tool that can be used in engineering practicte to estimate some bounds to the maximum horizontal in situ stress state. The approach is finally validated by means of both numerical simulations, performed with a sophisticated numerical tool, and experimental field data coming from the literature.

This study was conducted to develop and validate a more reliable total organic carbon (TOC) analytical procedure for water samples containing suspended solids (SS). The effects of the combined ultrasonic and alkaline pretreatment (CULA) on the TOC measurement were studied in water samples containing SS from three origins (algae, sewage particles, and soil) under different analytical conditions (SS concentration, oxidation methods, and sieve size). The applicability of turbidity as a homogeneity index was also evaluated. With CULA, TOC recovery remained high (&gt, 80%) for SS concentration ranges up to four times larger than ultrasonic pretreatment alone (UL) due to enhanced particulate organic carbon (POC) solubilization, and did not significantly differ depending on the oxidation methods, at low SS concentrations, or with varying sieve sizes. In particular, the turbidity change rate (i.e., NTU5/NTU0) of the pretreated water sample showed a high correlation with TOC precision (r2 = 0.73, p &lt, 0.01), which suggests that turbidity can be used as an indicator of sample homogeneity. A novel TOC analytical procedure is expected to be useful for more accurate assessments of the impact of particulate pollutants on water quality than current methods, and for the analysis of the carbon cycle, including POCs, in the environment.

This paper focuses on the point-to-point X-RAD connection system for the construction of cross laminated timber buildings in earthquake prone areas. Tests on X-RAD connectors subjected to “shear-tension” and “shear-compression” loading configurations are presented as supplement to the experimental data provided in previously published research. Tests aimed at characterizing the behavior of timber walls assembled with the system and loaded by lateral force are also reported. A capacity domain that allows for quick safety checks for any given load combination on the connector was derived from the experimental outcomes and is presented herein. An extremely simplified, yet effective numerical approach (the connector behavior is reproduced by 3-link elements) is proposed and compared with the experimental evidence. The 3-link model was able to reproduce with sufficient accuracy both, the elastic and post-elastic response of the walls. In the discussion section, particular attention is given to the system capability of dissipating energy and exhibiting ductile behavior.

Determination of the optical bandgap (E-g) in semiconductor nanostructures is a key issue in understanding the extent of quantum confinement effects (QCE) on electronic properties and it usually involves some analytical approximation in experimental data reduction and modeling of the light absorption processes. Here, we compare some of the analytical procedures frequently used to evaluate the optical bandgap from reflectance (R) and transmittance (T) spectra. Ge quantum wells and quantum dots embedded in SiO2 were produced by plasma enhanced chemical vapor deposition, and light absorption was characterized by UV-Vis/NIR spectrophotometry. R&T elaboration to extract the absorption spectra was conducted by two approximated methods (single or double pass approximation, single pass analysis, and double pass analysis, respectively) followed by Eg evaluation through linear fit of Tauc or Cody plots. Direct fitting of R&T spectra through a Tauc-Lorentz oscillator model is used as comparison. Methods and data are discussed also in terms of the light absorption process in the presence of QCE. The reported data show that, despite the approximation, the DPA approach joined with Tauc plot gives reliable results, with clear advantages in terms of computational efforts and understanding of QCE. ENERGETIC - PON00355_3391233 MIUR under project Beyond-Nano - PON a3_00363