scholarly journals Investigations on historical monuments’ deterioration through chemical and isotopic analyses: an Italian case study

2021 ◽  
Author(s):  
Maria Ricciardi ◽  
Concetta Pironti ◽  
Oriana Motta ◽  
Rosa Fiorillo ◽  
Federica Camin ◽  
...  
Keyword(s):  
Potassium Nitrate ◽  
Sewage Water ◽  
X Ray Diffraction ◽  
Italian Case ◽  
Historical Monuments ◽  
Isotopic Analyses ◽  
Historic Centre ◽  
The Church

AbstractIn this paper, we analysed the efflorescences present in the frescos of a monumental complex named S. Pietro a Corte situated in the historic centre of Salerno (Campania, Italy). The groundwater of the historic centre is fed by two important streams (the Rafastia and the Fusandola) that can be the sources of water penetration. The aims of this work are to (i) identify the stream that reaches the ancient frigidarium of S. Pietro a Corte and (ii) characterize the efflorescences on damaged frescos in terms of chemical nature and sources. In order to accomplish the first aim, the water of the Rafastia river (7 samples) and the water of the Fusandola river (7 samples) were analysed and compared with the water of a well of the Church (7 samples). The ionic chromatography measurements on the water samples allowed us to identify the Rafastia as the river that feeds the ancient frigidarium of S. Pietro a Corte. To investigate the nature and the origin of the efflorescences (our second aim), anionic chromatography analyses, X-ray diffraction measurements, and the isotopic determination of nitrogen were performed on the efflorescences (9 samples) and the salts recovered from the well (6 samples). Results of these analyses show that efflorescences are mainly made of potassium nitrate with a δ15N value of + 9.3 ± 0.2‰. Consequently, a plausible explanation for their formation could be the permeation of sewage water on the walls of the monumental complex.

scholarly journals A Control Based Mathematical Model for the Evaluation of Intervention Lines in COVID-19 Epidemic Spread: The Italian Case Study

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 890
Author(s):  
Paolo Di Giamberardino ◽  
Rita Caldarella ◽  
Daniela Iacoviello
Keyword(s):  
Mathematical Model ◽  
Equilibrium Points ◽  
Italian Case ◽  
Control Actions ◽  
Containment Measures ◽  
Asymptomatic Subjects ◽  
The Impact

This paper addresses the problem of describing the spread of COVID-19 by a mathematical model introducing all the possible control actions as prevention (informative campaign, use of masks, social distancing, vaccination) and medication. The model adopted is similar to SEIQR, with the infected patients split into groups of asymptomatic subjects and isolated ones. This distinction is particularly important in the current pandemic, due to the fundamental the role of asymptomatic subjects in the virus diffusion. The influence of the control actions is considered in analysing the model, from the calculus of the equilibrium points to the determination of the reproduction number. This choice is motivated by the fact that the available organised data have been collected since from the end of February 2020, and almost simultaneously containment measures, increasing in typology and effectiveness, have been applied. The characteristics of COVID-19, not fully understood yet, suggest an asymmetric diffusion among countries and among categories of subjects. Referring to the Italian situation, the containment measures, as applied by the population, have been identified, showing their relation with the government's decisions; this allows the study of possible scenarios, comparing the impact of different possible choices.

scholarly journals The Importance of “Contextualisation” in Small and Medium-Sized Firms Valuation: Evidences from an Italian Case Study

2017 ◽  
Vol 13 (1) ◽  
pp. 70
Author(s):  
Damiano Montani ◽  
Francesco Perrini ◽  
Daniele Gervasio ◽  
Andrea Pulcini
Keyword(s):  
Financial Flows ◽  
Italian Case ◽  
Company Value ◽  
Proper Definition ◽  
Theory Of Value ◽  
Definition Of ◽  
A Company ◽  
Correct Data

The valuation of a small or medium-sized enterprise through subjective methods, may not exclude a correct contextualisation of the data forming the information base of the estimate. “Contextualisation” refers to the general overview of all those elements that allow a proper definition of the enterprise’s background. All of this serves in the analysis for the correct data necessary for the determination of values such as the economic and financial flows to discount, the timeframe of analysis and the discount rate. Without a correct contextualisation, it is not possible to reach a correct measurement of the company value in accordance with the studies on the “theory of value”. After observing that “contextualisation” has not been widely studied till now for the theory of value, the present work analyses the incidence on the measurement of the company value, showing with an empirical case the different results that may be reached on the basis of the contextualisation of data. Hence, a correct “contextualisation” is crucial for the proper valuation of a company. Academic researches should take more carefully into consideration, this aspect concerning the valuation of a company and in particular, define more accurately the implementing rules in the assessment methods.

scholarly journals RENOVATION OF ROOF STRUCTURE OF HISTORICAL BUILDING – CASE STUDY

2021 ◽  
Vol 6 (2) ◽  
pp. 71-81
Author(s):  
Marcela Spišáková ◽  
Daria Mokrenko
Keyword(s):  
Point Of View ◽  
Historic Buildings ◽  
Historical Buildings ◽  
Historical Building ◽  
Roof Structure ◽  
Historical Monuments ◽  
Cost Parameters

On the present, the problem of renovation of historical buildings is becoming more and more actual. The role of society is to protect and renovate the historical monuments. The presented article focuses on the problem of renovation of historic buildings from a structural, technological and cost point of view. During the solution of the case study "Renovation of roof structure of the Old Town Hall in Košice", a variant solution of the historic roof renovation was designed in accordance with the principles of historical buildings renovation. Subsequently, the evaluation of the technological and cost parameters for renovation; and determination of the optimal variant for renovation of the historical roof was processed through the methods of multicriterial analysis.

scholarly journals Protogenetic sulfide inclusions in diamonds date the diamond formation event using Re-Os isotopes

Geology ◽  
2021 ◽  
Author(s):  
M.G. Pamato ◽  
D. Novella ◽  
D.E. Jacob ◽  
B. Oliveira ◽  
D.G. Pearson ◽  
...  
Keyword(s):  
Mantle Lithosphere ◽  
X Ray Diffraction ◽  
Diamond Formation ◽  
Monosulfide Solid Solution ◽  
X Ray ◽  
Os Isotopes ◽  
Isotopic Analyses ◽  
Continental Lithospheric Mantle ◽  
Os Isotope

Sulfides are the most abundant inclusions in diamonds and a key tool for dating diamond formation via Re-Os isotopic analyses. The manner in which fluids invade the continental lithospheric mantle and the time scale at which they equilibrate with preexisting (protogenetic) sulfides are poorly understood yet essential factors to understanding diamond formation and the validity of isotopic ages. We investigated a suite of sulfide-bearing diamonds from two Canadian cratons to test the robustness of Re-Os in sulfide for dating diamond formation. Single-crystal X-ray diffraction (XRD) allowed determination of the original monosulfide solid-solution (Mss) composition stable in the mantle, indicating subsolidus conditions of encapsulation, and providing crystallographic evidence supporting a protogenetic origin of the inclusions. The results, coupled with a diffusion model, indicate Re-Os isotope equilibration is sufficiently fast in sulfide inclusions with typical grain size, at mantle temperatures, for the system to be reset by the diamond-forming event. This confirms that even if protogenetic, the Re-Os isochrons defined by these minerals likely reflect the ages of diamond formation, and this result highlights the power of this system to date the timing of fluid migration in mantle lithosphere.

scholarly journals Refining bimodal microstructure of materials with MSTRUCT

2014 ◽  
Vol 29 (S2) ◽  
pp. S35-S41 ◽  
Author(s):  
Z. Matěj ◽  
A. Kadlecová ◽  
M. Janeček ◽  
L. Matějová ◽  
M. Dopita ◽  
...  
Keyword(s):  
Dislocation Density ◽  
Copper Sample ◽  
Bimodal Microstructure ◽  
X Ray Diffraction ◽  
Two Phase ◽  
Angular Pressing ◽  
Crystallite Sizes ◽  
Diffraction Peaks

The possibilities of modelling the diffraction profiles from bimodal microstructure in computer program MSTRUCT are demonstrated on two examples. A special “Double Component” profile effect can be utilized for such problems. At first it was applied to an analysis of a mixture of two nanocrystalline anatase powders with different crystallite sizes and the relative ratio of both components was determined from X-ray diffraction data. In the second case study, diffraction peaks from a pure polycrystalline copper sample treated by equal channel angular pressing were fitted using a two-phase model of large recrystallized defect-free grains and ultrafine crystallites with high dislocation density. The method is shown to be suitable for determination of the relative fraction of the microstructural components as well as other parameters (e.g. dislocation density).

Sem and X-Ray Analysis of Renal and Biliary Calculi

1976 ◽  
Vol 34 ◽  
pp. 306-307
Author(s):  
R. J. Narconis ◽  
G. L. Johnson
Keyword(s):  
Chemical Constituents ◽  
Natural State ◽  
X Ray Diffraction ◽  
Chemical Methods ◽  
X Ray ◽  
Additional Dimension ◽  
Biliary Calculi ◽  
Calculus Formation ◽  
Scanning Electron

Analysis of the constituents of renal and biliary calculi may be of help in the management of patients with calculous disease. Several methods of analysis are available for identifying these constituents. Most common are chemical methods, optical crystallography, x-ray diffraction, and infrared spectroscopy. The application of a SEM with x-ray analysis capabilities should be considered as an additional alternative.A scanning electron microscope equipped with an x-ray “mapping” attachment offers an additional dimension in its ability to locate elemental constituents geographically, and thus, provide a clue in determination of possible metabolic etiology in calculus formation. The ability of this method to give an undisturbed view of adjacent layers of elements in their natural state is of advantage in determining the sequence of formation of subsequent layers of chemical constituents.

Symmetry breaking in convergent-beam diffraction

1989 ◽  
Vol 47 ◽  
pp. 480-481
Author(s):  
D.J. Eaglesham
Keyword(s):  
Symmetry Breaking ◽  
Point Group ◽  
X Ray Diffraction ◽  
Multiple Diffraction ◽  
Space Groups ◽  
Atomic Displacements ◽  
Small Probe ◽  
Phase Sensitive ◽  
Convergent Beam

Convergent Beam Electron Diffraction is now almost routinely used in the determination of the point- and space-groups of crystalline samples. In addition to its small-probe capability, CBED is also postulated to be more sensitive than X-ray diffraction in determining crystal symmetries. Multiple diffraction is phase-sensitive, so that the distinction between centro- and non-centro-symmetric space groups should be trivial in CBED: in addition, the stronger scattering of electrons may give a general increase in sensitivity to small atomic displacements. However, the sensitivity of CBED symmetry to the crystal point group has rarely been quantified, and CBED is also subject to symmetry-breaking due to local strains and inhomogeneities. The purpose of this paper is to classify the various types of symmetry-breaking, present calculations of the sensitivity, and illustrate symmetry-breaking by surface strains.CBED symmetry determinations usually proceed by determining the diffraction group along various zone axes, and hence finding the point group. The diffraction group can be found using either the intensity distribution in the discs

A novel method for the determination of linting propensity of paper

TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD
Keyword(s):  
Ash Content ◽  
The Novel ◽  
Offset Printing ◽  
Excellent Correlation ◽  
End Conditions ◽  
Bottom Side ◽  
Novel Method ◽  
Total Fraction

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.

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