Arteoli IA

• The artist’s attitude towards materials is based on intuition, artistic ingenuity, and personal experience rather than on a scientific knowledge of the material’s properties.
• An example of the rapidly changing needs of modern society for specific conservation issues is the preservation of images and information on recently developed media.
• The dedicated scientist in conservation has a number of different strategies to improve the results considerably, for example by optimizing the source, changing the geometry of the measurement, or using more sensitive detectors.
• Two fundamental contributions should be introduced by the scientists involved in the technical operations: the proposal of alternative or complementary techniques to extract the maximum amount of information from the analysis, and optimization of the experimental methodologies to the specific needs of the problem.
• IPERION HS is a consortium of 24 partners from 23 countries that contributes to establishing a pan-European research infrastructure on heritage science.
• Conservation techniques should be appropriately based on well chosen samples and well posed questions.
• Non-standard instrumentation requires optimized measurement protocols, careful calibration, appropriate interpretation of the results, and comparison with standard measurements.
• The view of the curator and the conservator is that conservation issues involve scientific investigation to refine the descriptions of the objects.
• Scientifically speaking, the problem in conservation is to relate the kinetics of chemical processes to the human time scale.
• The issues to be considered in conservation are the reconstruction of the materials and the processes used at the time the object was produced (past), the understanding of the changes that have occurred since then (present), and the intervention to stop or slow down the processes of decay and alteration (future).
• Conservation of information includes written texts, images, digital recording.
• IPERION HS offers training and access to a wide range of high-level scientific instruments, methodologies, data and tools for advancing knowledge and innovation in heritage science.
• The probe in scientific experiments is usually a beam of electromagnetic radiation, though incident particle beams (electrons, neutrons and protons) are also used.
• In all experiments, three basic parameters of the incident/emitted radiation are to be measured, known, or assumed: the energy (or frequency, or wavelength), the direction, and the intensity of the beam.
• The energy and the direction carry the information on the nature and structure of the atoms in the samples at different levels, as discussed below, whereas the intensity of the measured beam is related to the number of interacting particles, atoms, or molecules, and is therefore the basis for quantifying the components of the system.
• If there is no energy exchange between the probing beam and the material, then the radiation is defined as being scattered elastically, and the process is described as diffraction (i.e wave interference).
• If the interaction involves an exchange of energy between the incident radiation and the atoms in the materials, i.e we have absorption and re- emission of radiation at defined frequencies, the process is anelastic and is treated as spectroscopy.
• Each instrument employs a specific kind of electromagnetic radiation or particle to probe matter, and measures only a narrow selection of the re- emitted radiation or particles, optimizes the technical design of each laboratory instrument for rather specific experiments, and is usually limited to one kind of measurement.
• Non-invasive sampling techniques include routine/fast, time-consuming, and fast methods.
• The probed volume of each technique specifically probes a certain volume of the material investigated, which depends on the size and collimation of the incident beam, the penetration of the beam into the material, the energy of the beam, and the chemical nature and density of the material.
• Mesoscopic level (heterogeneities at the 10^-6 - 10^-3 m scale) is related to the shape and orientation of crystals in single-phase or multiple-phase crystalline aggregates and is essentially measured by electron and optical microscopy techniques or by techniques that are sensitive to crystal orientation (texture analysis).
• Macroscopic level (heterogeneities above 10^-3 m scale) is related to the macroscopic properties of the materials, from millimetre-sized specimens to samples as large as whole buildings, archaeological sites, or geographical areas and is commonly measured by imaging techniques and all techniques measuring the physical properties of the materials.
• Microscopic level (heterogeneities at the 10^-8 - 10^-5 m scale) is related to the long range ordering of atoms into the crystalline state and is essentially measured by analytical chemistry techniques or atomic/molecular microscopy.
• The choice of the scale at which the object is being investigated must be based on the probed volume and representativity.
• The representativity of the sample is related to the scale of the heterogeneities present in the sample, and whether the measurements are made on average values or spatial distributions of the experimental parameters.
• Invasive sampling techniques include metallography, CTA (Crystallographic texture analysis), and drilling.
• The resulting information provided by measurements is one of the following: the chemical nature of the material, the physical status of the material, the mineralogical nature of the material, and the age.
• The intrinsic nature of natural and synthetic materials is highly heterogeneous, and can be perceived at different levels, from the atomic to the macroscopic.
• Atomic or nanoscopic level heterogeneities are related to single atoms, atoms clusters, or single molecules.
• In real life most samples are made of a small number of elements that make up most of the compound (major elements), and a certain number of elements that make up almost all the rest of the compound (minor elements).
• The elements that are present below the 0.1 wt % level (1000 ppm) are arbitrarily considered to be trace elements.
• If the object hit by the X-rays is not periodic, there is no diffraction, only diffuse scattering.
• In the case of a periodic object, there is diffraction and the image is the reciprocal lattice.
• The smallest concentration that we can measure with a particular technique is defined as three times the signal corresponding to the instrumental noise level (or background, i.e. the signal detected when no sample is measured), and it is called the detection limit (DL), or limit of detection (LoD).
• If the σ has been correctly evaluated, then an element is present when its measured value is at least 3 σ.
• Thermal/pulsed neutrons, synchrotron X-rays, penetrating beams, and large objects are examples of non-invasive techniques.
• René Just Haüy (1743 - 1822) is recognized for the Law of rational indices.
• Max von Laue discovered the diffraction of X-rays by crystals in 1912.
• Mathematician Johannes Kepler explored the snowflake's six-fold geometry in 1611.
• Niccolo' Stenone (1638 - 1686) and Jean-Baptiste Louis Romé de l' Isle (1736 – 1790) are recognized for the Law of Constancy of the Angles.