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In-situ synchrotron X-radiography studied the impact of TiCN nanoparticles (TiCNnp) on α-Al dendrite morphology and growth in Al–13Cu–7Si alloys. Comparative experiments were conducted without nanoparticles and with the addition of Al–5Ti–1B. Despite Al–5Ti–1B had almost no refining effect, 0.5% TiCNnp notably reduced α-Al grain size of Al–Cu–Si alloys, especially at higher cooling rates. When cooled at a rate of 0.2K/s, the dendrite tip radius of α-Al with the addition of TiCNnp (18.2 μm) was approximately twice as large as that without nanoparticles (9.8 μm). Concurrently, the primary dendrite growth rate of α-Al without nanoparticles exceeded that with TiCNnp by approximately 15 times. This discrepancy can be attributed to the coarser dendrite tip of α-Al induced by TiCNnp, which led to a greater solute accumulation in front of the tip. Furthermore, the area growth rate of both grain and solute suppressed nucleation zone (SSNZ) with addition of TiCNnp was only one-tenth of that observed with Al–5Ti–1B. Consequently, the incorporation of TiCNnp resulted in a significantly smaller nucleation-free zone, facilitating the activation of a greater number of nucleation sites within the melt. This study sheds light on the growth inhibition mechanism of TiCNnp in Al–Si alloys.

The solute diffusion zone plays a critical role in determining nucleation efficiency during heterogeneous nucleation. In this study, in-situ synchrotron X-radiography and numerical modeling were employed to investigate the Solute Suppressed Nucleation Zone (SSNZ) surrounding growing equiaxed grains in Al-13Cu alloys. Quantitative analysis of SSNZ and constitutional undercooling was conducted using image processing techniques. Solute concentration and SSNZ length in the direction exceed those in the direction, suggesting higher solute enrichment in dendrite centers. This causes greater undercooling in the dendrite growth direction () with faster dendrite growth rates. As equiaxed dendrites grow, SSNZ length in the direction decreases while increasing significantly in the direction. Utilizing data obtained from numerical simulations, we refined the analytical equation governing solute distribution preceding the solid–liquid interface under three-dimensional conditions, and the computational equation determining the SSNZ length. The SSNZ lengths derived from the optimized equation along the and directions demonstrate more agreement with both experimental observations and numerical simulation outcomes. Higher growth rates rapidly increase undercooling, limiting the development of nucleation-free zone. Additionally, SSNZ area growth slows at higher cooling rate, correlating with increased solute concentration and reduced area in SSNZ.

Seismic observations show the Earth's inner core has significant and unexplained variation in seismic attenuation with position, depth and direction. Interpreting these observations is difficult without knowledge of the visco‐ or anelastic dissipation processes active in iron under inner core conditions. Here, a previously unconsidered attenuation mechanism is observed in zinc, a low pressure analog of hcp‐iron, during small strain sinusoidal deformation experiments. The experiments were performed in a deformation‐DIA combined with X‐radiography, at seismic frequencies (∼0.003–0.1 Hz), high pressure and temperatures up to ∼80% of melting temperature. Significant dissipation (0.077 ≤ Q−1(ω) ≤ 0.488) is observed along with frequency dependent softening of zinc's Young's modulus and an extremely small activation energy for creep (⩽7 kJ mol−1). In addition, during sinusoidal deformation the original microstructure is replaced by one with a reduced dislocation density and small, uniform, grain size. This combination of behavior collectively reflects a mode of deformation called "internal stress superplasticity"; this deformation mechanism is unique to anisotropic materials and activated by cyclic loading generating large internal stresses. Here we observe a new form of internal stress superplasticity, which we name as "elastic strain mismatch superplasticity." In it the large stresses are caused by the compressional anisotropy. If this mechanism is also active in hcp‐iron and the Earth's inner‐core it will be a contributor to inner‐core observed seismic attenuation and constrain the maximum inner‐core grain‐size to ≲10 km. Plain Language Summary: The Earth's inner‐core is the most remote and inaccessible part of our planet. Knowledge of the inner‐core's structure comes from interpretation of the information held in seismic waves that have passed through the inner‐core. These waves show measurable variation in wave speed and damping with depth. To investigate the wave damping in the inner‐core we performed experiments that mimicked the passage of seismic waves through zinc. Zinc was used as a low‐pressure analog because it has the same crystallographic structure as the iron in the inner‐core. In these experiments, we observed new behavior in the zinc samples that can only be explained by the behavior of different directions within the zinc crystal lattice. These we named "elastic strain mismatch superplasticity" and if the same phenomena occurs in the Earth's inner‐core it could explain the seismic observations. Key Points: Zinc, a low pressure analog for hcp‐iron, deforms by internal stress superplasticity during small amplitude sinusoidal‐strain deformationInternal stress superplasticity due to mechanical oscillations has not been previously reportedInternal stress superplasticity is another attenuation mechanism that could be active in the Earth's inner‐core [ABSTRACT FROM AUTHOR]

Abstract Seismic observations show the Earth's inner core has significant and unexplained variation in seismic attenuation with position, depth and direction. Interpreting these observations is difficult without knowledge of the visco‐ or anelastic dissipation processes active in iron under inner core conditions. Here, a previously unconsidered attenuation mechanism is observed in zinc, a low pressure analog of hcp‐iron, during small strain sinusoidal deformation experiments. The experiments were performed in a deformation‐DIA combined with X‐radiography, at seismic frequencies (∼0.003–0.1 Hz), high pressure and temperatures up to ∼80% of melting temperature. Significant dissipation (0.077 ≤ Q−1(ω) ≤ 0.488) is observed along with frequency dependent softening of zinc's Young's modulus and an extremely small activation energy for creep (⩽7 kJ mol−1). In addition, during sinusoidal deformation the original microstructure is replaced by one with a reduced dislocation density and small, uniform, grain size. This combination of behavior collectively reflects a mode of deformation called “internal stress superplasticity”; this deformation mechanism is unique to anisotropic materials and activated by cyclic loading generating large internal stresses. Here we observe a new form of internal stress superplasticity, which we name as “elastic strain mismatch superplasticity.” In it the large stresses are caused by the compressional anisotropy. If this mechanism is also active in hcp‐iron and the Earth's inner‐core it will be a contributor to inner‐core observed seismic attenuation and constrain the maximum inner‐core grain‐size to ≲10 km.

In high pressure multi-anvil experiments X-radiography is used to ascertain strain in deforming samples because the tooling prevents optical or other direct observations of the sample. The processing of these X-radiographic images to determine bulk sample strain is one of the limiting factors to making measurements closer to the strains and strain-rates that occur during mantle convection or the passage of seismic waves. Typically, sample deformation in these experiments is tracked by the displacement of high-contrast marker foils in X-radiographs. X-radiographs are treated individually or pairwise in a multi-step process that tracks the displacement of marker foils during experiments. Here I develop a new algorithm, FoilTrack, that treats all the X-radiographic observations in a single-step process, resulting in improved accuracy and consistency of length changes determined from X-radiographic images, as well as providing more realistic parameter uncertainty. The improvements are demonstrated using data from small-strain sinusoidal deformation experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • The SSNZ and undercooling were quantitatively analyzed via in-situ X-radiography and numerical simulations. • Numerical modeling demonstrated changes in grain and SSNZ sizes consistent with in-situ X-radiography results. • The analytical equations for solute distribution and SSNZ length in three-dimensional conditions were modified. The solute diffusion zone plays a critical role in determining nucleation efficiency during heterogeneous nucleation. In this study, in-situ synchrotron X-radiography and numerical modeling were employed to investigate the Solute Suppressed Nucleation Zone (SSNZ) surrounding growing equiaxed grains in Al-13Cu alloys. Quantitative analysis of SSNZ and constitutional undercooling was conducted using image processing techniques. Solute concentration and SSNZ length in the <110> direction exceed those in the <100> direction, suggesting higher solute enrichment in dendrite centers. This causes greater undercooling in the dendrite growth direction (<100>) with faster dendrite growth rates. As equiaxed dendrites grow, SSNZ length in the <100> direction decreases while increasing significantly in the <110> direction. Utilizing data obtained from numerical simulations, we refined the analytical equation governing solute distribution preceding the solid–liquid interface under three-dimensional conditions, and the computational equation determining the SSNZ length. The SSNZ lengths derived from the optimized equation along the <100> and <110> directions demonstrate more agreement with both experimental observations and numerical simulation outcomes. Higher growth rates rapidly increase undercooling, limiting the development of nucleation-free zone. Additionally, SSNZ area growth slows at higher cooling rate, correlating with increased solute concentration and reduced area in SSNZ. [ABSTRACT FROM AUTHOR]

Scientific analyses of the traditional materials and methods in thangka production are uncommon, as thangkas are sacred objects, the sampling of which is discouraged, in order to preserve their integrity. This study builds on this important ethical challenge and presents a three-stage methodology that systematically delves deeper into each layer of the composition, successfully enabling the investigation of different phases of production. In the first stage, visual examination of the painting, including observations under magnification, was used to assess its condition. In the next step, the infrared reflected (IRR) and short-wave infrared (SWIR) images revealed the underdrawing and instances of modifications as well as colour notations. Additionally, ultraviolet-induced visible luminescence (UVL), infrared-reflected false colour (IRRFC) and X-ray images provided important preliminary information on the colourants present, the nature of the underdrawing, and the painting technique. In the final stages, fibre optic reflectance (FORS), Fourier-transform infrared (FTIR) and Raman spectroscopies confirmed the identity of many of the pigments (cinnabar/vermillion, minium, iron oxide, malachite, azurite, indigo, Indian lac), the ground and the binder used for the blue and green paint layers. In addition, key details of practices and materials were revealed, that may indicate provenance or other information of scholarly importance. These will constitute a helpful comparison to existing and future studies of other thangkas. [ABSTRACT FROM AUTHOR]

Simple Summary: The commercially popular Sabah grouper has gained attention due to its high growth rate. Our preliminary study briefly reported how temperature and diet affect gastric emptying time and specific growth rate of hybrid Sabah grouper; however, a comprehensive study on gastrointestinal evacuation GE (Gastrointestinal time together with gastric emptying rate) of adult hybrid Sabah grouper at different temperatures and diets has yet to be conducted. In this follow-up study, we suggest that the optimum temperature and feed for adult Sabah grouper are 30 °C and trash fish, respectively. This study explores the gastrointestinal evacuation time (GET) and gastrointestinal evacuation rate (GER) of the popular Sabah grouper (Epinephelus fuscoguttatus × E. lanceolatus) adults using two established methods (X-radiography and serial slaughter) and square root modeling using different temperatures: 28 °C, 30 °C, 32 °C, and 34 °C and different diets: pellet (ash: 11.4 ± 0.08; moisture: 29.0 ± 0.01; protein 37.5 ± 0.80; lipid 15.0 ± 0.13) and trash fish: Sardinella sp. (ash: 2.3 ± 0.15; moisture: 78.5 ± 0.33; protein 55.4 ± 0.62; lipid 7.3 ± 0.25) and the impact on growth indices. The results indicate that the GET shortened as temperature increased from 28 °C to 30 °C; however, it was prolonged when it surged to 32 °C and 34 °C. The groupers fed with trash fish at a temperature of 30 °C had the shortest GER (0.41 ± 0.10 g hr−1) whereas groupers fed with pellet at 34 °C had the longest GER (0.95 ± 0.02 g hr−1). Likewise, the highest SGR (16.25 ± 2.11% day−1) was observed at 30 °C for groupers fed with a trash fish diet. The condition (K) value was lowest at 34 °C for groupers fed with a pellet diet (1.01 ± 0.04) and highest at 30 °C for groupers fed with trash fish (1.45 ± 0.04). Our results suggest that temperature and diet influence growth indices and GE of adult Sabah groupers. Incorporation of this information will allow better management of this commercially important grouper species when reared in a controlled aquaculture environment. [ABSTRACT FROM AUTHOR]

This article presents the results of a study conducted on The Feast of Dionysius I, a previously unknown painting attributed to Henryk Siemiradzki (1843–1902), one of the most prominent Polish painters of the nineteenth century. Analyses were performed to verify the proposed artist. The results were surprising. Not only did they confirm the authenticity of the work, but they also revealed another paint sketch underneath. We determined that the first chronologically created composition was a unique study for Siemiradzki's famous large-scale painting, Nero's Torches. It was possible to draw these conclusions by using of imaging at a range of wave lengths and by conducting multiple analyses with the following techniques: optical microscopy in visible light and ultraviolet radiation, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray fluorescence spectrometry, and Fourier transform infrared spectroscopy. Our findings were also supported by documentary sources. The results of these analyses were then compared with the database regarding the materials (including pigments) and methods of executing paintings applied by Henryk Siemiradzki. The database was compiled based on the examinations conducted in the National Museum in Krakow of Siemiradzki's 75 oil paintings. [ABSTRACT FROM AUTHOR]

This study investigates the potential of a new high-resolution, non-destructive, X-ray imaging technique for the Quaternary Sciences – computed laminography (CL). Greyscale properties are systematically extracted from digital X-radiographic CL images of cored glaciomarine sediments to analyse and characterise sediments at pixel-scale resolution (

A type of electromagnetic radiation known as X-rays has been known in ceramic research since the 1930s. X-radiography is applied mainly to investigate clay fabric and to identify manufacturing details. In clay fabric identification, the method could be used to determine size, proportions, type and even general mineralogy of inclusions or tempers. Moreover, it can be successfully applied to identify, verify or better understand primary forming techniques as well. The purpose of this paper is to investigate Egyptian Predynastic pottery production by means of X-radiography in order to determine the primary forming techniques used for making four small ceramic vessels: bag-shaped jars and lemon-shaped jar from the cemetery at Minshat Abu Omar in the Eastern Nile Delta. The vessels are now in the collection of the Poznań Archaeological Museum and X-radiography was chosen as the study method because of its non-destructive nature allowing to penetrate the walls of vessels from the museum collection. Two primary forming techniques (pinching and coil-building) were identified during the analysis. The studied vessels were made of two segments by hand. Pinching was used to build the belly, while the shoulder, neck and rim were made by coiling. The application of two different forming techniques as well as the effort invested in joining coils and vessel segments imply that their makers were fairly skilled in their craft. The vessels reveal these ‘secrets of the trade’ only when exposed to X-rays.

This study explores the gastrointestinal evacuation time (GET) and gastrointestinal evacuation rate (GER) of the popular Sabah grouper (Epinephelus fuscoguttatus × E. lanceolatus) adults using two established methods (X-radiography and serial slaughter) and square root modeling using different temperatures: 28 °C, 30 °C, 32 °C, and 34 °C and different diets: pellet (ash: 11.4 ± 0.08; moisture: 29.0 ± 0.01; protein 37.5 ± 0.80; lipid 15.0 ± 0.13) and trash fish: Sardinella sp. (ash: 2.3 ± 0.15; moisture: 78.5 ± 0.33; protein 55.4 ± 0.62; lipid 7.3 ± 0.25) and the impact on growth indices. The results indicate that the GET shortened as temperature increased from 28 °C to 30 °C; however, it was prolonged when it surged to 32 °C and 34 °C. The groupers fed with trash fish at a temperature of 30 °C had the shortest GER (0.41 ± 0.10 g hr−1) whereas groupers fed with pellet at 34 °C had the longest GER (0.95 ± 0.02 g hr−1). Likewise, the highest SGR (16.25 ± 2.11% day−1) was observed at 30 °C for groupers fed with a trash fish diet. The condition (K) value was lowest at 34 °C for groupers fed with a pellet diet (1.01 ± 0.04) and highest at 30 °C for groupers fed with trash fish (1.45 ± 0.04). Our results suggest that temperature and diet influence growth indices and GE of adult Sabah groupers. Incorporation of this information will allow better management of this commercially important grouper species when reared in a controlled aquaculture environment.

In situ synchrotron x-ray radiography studies on the solidification sequences of non-refined and refined Al-20Zn alloys were carried out. The dendrite growth, porosity evolution, grain densities and growth rates were measured. Without and with 0.05% grain refiner, the solidification sequences appear as columnar dendrite. The average columnar dendrite growth rate of non-refined Al-20Zn alloy is larger than refined by 0.05% grain refiner. The burst growth is happened in columnar dendrite which is the first report and the time interval was about 1.2s. The columnar interdendritic region is prone to form porosities with solidification progress. The equivalent diameter of porosity with time is well fitted by Gaussian function, and the growth velocities of porosities of all sequences are faster in the first seven seconds and fluctuated with time. When the addition level of grain refiner is larger than 0.1%, the solidification sequences appear as equiaxed dendrite. The accumulation of grains of refined Al-20Zn alloys is well fitted by logistic function. The porosities disappeared during solidification with equiaxed grains. The equiaxed dendritic growth velocity, which is ~16μm/s at a cooling rate of 8K/min, is much lower than columnar. [ABSTRACT FROM AUTHOR]

• Non-invasive imaging techniques support visual examination of knotted-pile carpets. • Weaving structure and condition assessed with X-radiography and VSC techniques. • NUV and NIR imaging with VSC and micro-CT offer details about weaving features. • Digital mapping of areas of material loss, repairs or contaminations with VSC and CT. • Efficient digital mapping of the condition of entire objects with CT. The appraisal of the design and the weaving structure of Islamic knotted-pile carpets can tell plenty about the context in which they were produced, and the identification of signs of deterioration can help to establish their condition. These are often somewhat imprecise and laborious examinations, especially when considering carpets of large dimensions. Analytical methods that support these disciplines urge further exploration so that improved interpretations can be obtained. An interdisciplinary combination of art history, analytical science and textile conservation aimed, on the one hand, to improve the weaving examination of these complex textile objects – by considering the spin of threads and the ply of yarns; the knot count and density; and the weaving structure of warps, wefts and piles – and on the other, to help their condition assessment – by mapping of damaged areas, old repairs and contaminations. For this purpose, the possibilities and limitations of several non-invasive imaging techniques, namely transmitted, raking or incident visible, ultraviolet (UV) and infrared (IR) illumination through Visual Spectral Comparator (VSC), as well as conventional X-radiography, mammography and (micro) CT scanning, were assessed to support the conventional visual examination of the weaving details and present condition of two 17th-century Safavid knotted-pile carpet fragments. Observation with NUV and NIR imaging with VSC, as well as CT techniques, offered enriching overviews about weaving characteristics, damaged areas or contaminations that were not easily discernible with the naked eye, thus supporting the conventional visual examination. As a result, detailed digital mappings about the technological structure and the condition of the fragments could be obtained in a relatively efficient and accessible way. Moreover, combining art historical identification of the design with the analysis of the weaving structure confirmed that both carpet fragments are border corners that originally belonged to much larger carpets made in the so-called "Indo-Persian" style. The outcome of this interdisciplinary research brings very useful contributions for future art historical and conservation assessments of historical carpets, and it encourages further exploration of imaging techniques in the examination of other textile objects in museums and private collections. [ABSTRACT FROM AUTHOR]

A type of electromagnetic radiation known as X-rays has been known in ceramic research since the 1930s. X-radiography is applied mainly to investigate clay fabric and to identify manufacturing details. In clay fabric identification, the method could be used to determine size, proportions, type and even general mineralogy of inclusions or tempers. Moreover, it can be successfully applied to identify, verify or better understand primary forming techniques as well. The purpose of this paper is to investigate Egyptian Predynastic pottery production by means of X-radiography in order to determine the primary forming techniques used for making four small ceramic vessels: bag-shaped jars and lemon-shaped jar from the cemetery at Minshat Abu Omar in the Eastern Nile Delta. The vessels are now in the collection of the Poznań Archaeological Museum and X-radiography was chosen as the study method because of its non-destructive nature allowing to penetrate the walls of vessels from the museum collection. Two primary forming techniques (pinching and coil-building) were identified during the analysis. The studied vessels were made of two segments by hand. Pinching was used to build the belly, while the shoulder, neck and rim were made by coiling. The application of two different forming techniques as well as the effort invested in joining coils and vessel segments imply that their makers were fairly skilled in their craft. The vessels reveal these 'secrets of the trade' only when exposed to X-rays. [ABSTRACT FROM AUTHOR]

A controversial set of elite jewels assumed to be of early medieval period, recovered in 1937–1938 from a burial site in Matzhausen (northeastern Bavaria) was investigated to determine their technological coherency as well as their authenticity. The discovery of these jewels was exploited by German nationalists to argue that the material culture observed in Bohemia and Moravia in the ninth century had Germanic roots. The circumstances of their discovery, however, remain unclear. Research in archives demonstrated the involvement of the SS Ahnenerbe organisation in the recovery of the jewels. Are these jewels authentic or are they forgeries manufactured or modified by a modern craftsman to serve German expansionist nationalism? Three jewels recovered in the grave – a gombik (hollow spherical pendant), an earring with chainlet, and a zoomorphic figurine – were investigated using scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX), X-radiography, and stereomicroscopy. The investigation revealed a very heterogeneous set of objects with respect to technology and state of preservation. It also uncovered repairs and past invasive interventions involving modern metal and solder. Comparison with similar types of jewels from Bohemia and Moravia points to important differences in construction and technology, which confirms the uniqueness of this set of objects and casts suspicion on their authenticity. [ABSTRACT FROM AUTHOR]

Highlights • Development of a state-of-the-art computed tomography system capable of tracking ballistic-velocity unbounded material through a three-dimensional coordinated system. • Utilizes flash X-radiography technology to penetrate outer material layers. • Utilizes customized iterative reconstruction routines within Lawrence Livermore National Laboratory's "Livermore Tomography Tools" software suite to computationally reconstruct multiple X-ray projections into a 3-D volume. • Demonstrates the first example using a bullet penetrating an aluminum plate. Abstract The U.S. Army Research Laboratory (ARL) and Lawrence Livermore National Laboratory have developed a high speed computed tomography system that is capable of tracking unbounded material flux through a reconstruction volume at ballistic rates. It achieves this feat by creating three individual time-registered volume reconstructions throughout the duration of a single dynamic event. Each individual volume reconstruction is computed from five attenuation projections, which are collected using five flash X-ray sources and five digital imaging plate detectors. This work summarizes the numerous complexities in combining the 15 sources and 15 detectors into a single diagnostic, the complexities of analyzing multiple reconstruction volumes from a limited number of views, and complications associated with designing an experiment to fit within the bounding conditions of the diagnostic. It continues to demonstrate an example of how free-flowing material propagates through a reconstruction volume during a bullet/target interaction. [ABSTRACT FROM AUTHOR]

Abstract We report on a dendrite orientation transition (DOT) discovered in the Al Ge system by conducting isothermal solidification experiments in thin samples under slow cooling conditions. The DOT was revealed using a combination of in situ X-radiography imaging and post-mortem electron backscatter diffraction. In Al-20 wt% Ge the primary arms grow along 〈 100 〉 , whereas in Al-46 wt% Ge the primary arms grow along 〈 110 〉. At an intermediate composition of Al-29 wt% Ge, we observe both directions growing simultaneously. Phase-field simulations in which the solid-liquid interfacial energy anisotropy was systematically varied to correspond with the composition changes reproduced the experimentally observed microstructures. The remarkable agreement between the experimental observations and the simulations provides strong evidence that the DOT in this alloy system is caused by modification of surface energy anisotropy with increasing Ge content. Furthermore, we show that the confinement due to the thin sample geometry influences the selection of the primary growth directions, so that different growth morphologies develop depending on the orientation of the crystal in the sample. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Very few real easel paintings have been scanned by means of terahertz time-domain imaging (THz-TDI) up to now. In this study, four different areas of an eighteenth century easel painting have been scanned by THz-TDI with the aim of proving useful information to the conservators for its imminent restoration treatment, owing to the complexity of its structure. Despite the unevenness of the layers composing the painting (lining canvas, original canvas, patching materials, and paint layers), the recorded THz dataset has been processed so that the THz images of the single layers composing the multilayered object have been clearly obtained. Relevant information about the painting structure, the presence of structural defects, overpainting, and the existence and extension of the original remains could have been determined. Infrared photography and X-ray radiography have been used for integrating the collected THz data and comparing the different outputs. [ABSTRACT FROM AUTHOR]

Two paintings on metal support have been imaged by terahertz time-domain imaging (THz-TDI) in a reflection setup and the X-ray radiographs were also recorded. The study was performed for testing the terahertz radiation (THz) as an imaging method alternative to X-ray radiography, which suffers several limitations in imaging paint layers on metal support. While the information regarding the paint layers of the paintings was almost lost in the records provided by the X-ray radiography, THz-TDI demonstrates the ability to provide important information about them, despite the presence of the underlying metal. [ABSTRACT FROM AUTHOR]

Microscopic examination and analysis (metallography, X-radiography, SEM-EDS, pXRF and μ-XRF) of a group of stylistically linked gold alloy pendants from western and north-western Colombia confirms the use of a highly unusual manufacturing technique for the region. While the Darién pendants were made using lost-wax casting by a diverse group of cultures from southern Colombia through Costa Rica, only one subset of pendants produced in the Gran-Zenú region (the Caribbean lowlands of northern Colombia) and the Chocó region (the Pacific area of western Colombia) in the Early Period ( ad 0-900) was found to be manufactured by hammering of gold sheet and fine wires followed by hard soldering of components to produce true filigree. Similarities in features between the stylistically related cast and hammered pendants suggest that the hammered pendants may have served as a prototype for the cast versions. Other possible instances of hard soldering in the region are also presented. [ABSTRACT FROM AUTHOR]

Four easel paintings attributed to Hermenegildo Bustos ( Purísima del Rincón, Guanajuato, Mexico), one of the most renowned painters of the late nineteenth and early twentieth century Mexican art, have been investigated by means of terahertz time-domain imaging (THz-TDI) and standard imaging techniques, such as near-IR reflectography and X-ray radiography. The archival sources and the recent studies on the paintings suggest that the artworks were created in the eighteenth century and underwent several modifications since then until the intervention of Bustos who authored the currently visible depictions. By combining the records of the paintings obtained by imaging with the different methodologies, aspects of the previous depictions and further details on the paintings' history have been revealed, with THz-TDI playing a key role in attributing a chronological evolution of the images. The paintings of Purísima are the first THz-TDI-scanned paintings belonging to the Mexican cultural heritage. [ABSTRACT FROM AUTHOR]

Kuk Swamp is a globally significant archaeological site of early agriculture in the highlands of Papua New Guinea. Mixed-method and multi-scalar investigations of the stratigraphy and selected feature fills at Kuk were instrumental in determining the character of plant exploitation and agricultural practices there during the early and mid Holocene. In this paper, macro-scale (field recording), meso-scale (X-radiography) and micro-scale (thin section micromorphology) analyses are presented in summary form for a stratigraphic column, as well as for a palaeochannel and palaeosurfaces associated with plant exploitation at c.10,000 cal BP and cultivation at 7000–6400 cal BP. Major and minor stratigraphic units have been characterised, primary and secondary formation processes differentiated, and the anthropic associations of specific stratigraphic units determined, especially in regards to cultivation. The Kuk research highlights several methodological problems with the investigation of early cultivation on allophane-rich soils in tropical environments. [ABSTRACT FROM AUTHOR]

Measurement of root system attributes is of critical importance to understand and model plant growth. Root length density, the length of roots per unit volume of soil, is one of the important parameters required to understand plant performance. Measuring techniques currently in use to assess this parameter, such as for example core washing, are notoriously imprecise and labour-intensive. Roots and soil being inextricably linked, it is virtually impossible to separate them without loosing a significant amount of the root sample to be measured. This noticeably compromises the accuracy of washing techniques. For this reason, non-invasive measurement approaches are highly desirable. Here, a method based on the combination of X-radiography and image analysis is proposed as a new alternative for the measurement of root length density from intact samples. The successive steps of the method, from sampling to image acquisition are briefly described. A specific measurement algorithm, designed to account for the complex spatial arrangement of the roots within the samples is then presented and discussed in detail.

The Foundation of the American Institute for Conservation oral history archive, which began in 1975, contains almost 300 interviews with pioneer conservators, conservation scientists, and art historians. Technical examination and technical art history, as exemplified by Roger H. Marijnissen’s publications, has undergone many changes since the 1950s; this article briefly surveys the field, focusing on the examination of easel paintings, with the aid of voices and personal observations from the interviews available in the international oral history archive of the Foundation of the American Institute for Conservation.

Abstract This study examines the way long-term feed intake should be recorded accurately for selective breeding purposes, and estimates selection potential in feed intake using the X-ray method to record individual daily feed intake in rainbow trout (Oncorhynchus mykiss). The analysis showed that the point estimates of daily feed intake displayed low repeatabilities (r = 0.09–0.32). This indicates that a minimum of three repeated records were needed to accurately record average feed intake at a fixed age. To effectively breed for feed intake over the whole growing period, it is necessary to determine average feed intake at different ages, since there were only moderate phenotypic and genetic correlations between average daily feed intake recorded at 140 g, 750 g and 2000 g wet mass. Heritability for average daily feed intake was low (average h2 = 0.10), indicating that modest genetic changes can be obtained in response to selection. It was concluded that selection to genetically change long-term feed intake can be successful, yet repeated observations at several life stages are needed to ensure the accuracy of feed intake estimates and the efficiency of selection.

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The activity of wheel-throwing a ceramic vessel is governed by a number of physical forces. These are the rotational kinetic energy (expressed in terms of angular velocity and the moment of inertia) and manual pressures. Given the importance of the potter's wheel worldwide, and the frequently postulated socio-cultural meaning of wheel-throwing in particular, foundational research on the physics behind wheel-throwing has been under-represented, and there is a lack of understanding of the relationship between speed of wheel rotation, lifting speed and the orientation of clay pores or inclusions. The speed of rotation is highly relevant as different wheels can achieve different speeds. Thus, knowing the speed during manufacture may allow scholars to reconstruct the original device, manufacturing technique, and perhaps even the potter's level of skill. Two contrasting views can be found in the literature: a) there is a direct positive relationship between these variables, and that the angle of the inclusions/voids can therefore tell us about the wheel's speed at the time of making the pot and hence the device used; b) because pots are never thrown in one single motion, the angle of inclusions/voids is an averaging of all actions executed by the potter, and thus cannot provide meaningful inferences about speeds or device. Experiments with professional potters were devised to explore the relationship between these variables. They show that the interaction between the various physical forces, clay and potter is complex, leading to a large variance even within the work of a single potter, with finger pressure recognized as a major influencing variable. It is clear that angles of inclusions or voids cannot be used to project backwards to the wheel speed, lifting speed, skill level or device used. • Diagonal angle alignment of inclusions or voids identifies a vessel as wheel-thrown • Inclusion/void orientation does not allow retrospective deductions on wheel speed, lifting speed, the device used or a potter's skill • Inclusion or void orientation varies intra- and inter-potter • Finger pressure is most likely responsible for the steep inclusion or void orientation characteristic of wheel-throwing [ABSTRACT FROM AUTHOR]

We investigate the interaction between three-phase eutectic and a primary phase during solidification of an off-eutectic Al-Ag-Cu alloy through correlative imaging. In situ synchrotron X-radiography reveals the locations and orientations of primary Al 2 Cu rods, with respect to the surrounding eutectic. We also identified an unusually high and anisotropic eutectic growth velocity, often exceeding 100 μ m/s when the growth front was parallel to the surface of a primary Al 2 Cu rod. By combining these results with three-dimensional (3D) focused ion beam tomography, scanning electron microscopy, and electron backscatter diffraction, we demonstrate that this anomaly results from two-dimensional (2D) dendrites, or 'fingers', of Al and Ag 2 Al that spread along the primary Al 2 Cu rod surfaces; meanwhile, protrusions of Al 2 Cu grow in between pockets of the fingers and into the surrounding eutectic, preserving their crystallographic orientations and morphology in the process. We propose a competitive growth relationship between the three phases of the eutectic to explain these features as well as the diversity of two- and three-phase microstructures obtained at the onset of eutectic solidification. • Observed the interaction between three-phase eutectic and primary phase during solidification via in situ X-radiography. • Identified high and anisotropic eutectic growth velocities depending on proximity of eutectic front to the primary phase. • Traced the origin to 2D dendrites, or 'fingers', of two eutectic phases that spread across the primary rod surfaces. • Found that protrusions of primary phase extend between fingers to merge with and control the eutectic microstructure. • Proposed competitive growth relationship to explain these phenomena and diversity of two- and three-phase microstructures. [ABSTRACT FROM AUTHOR]

This article celebrates fifty years of the series of pattern books by Janet Arnold and shares some of her unpublished drawings from patterns that remain unpublished; these are scheduled for inclusion in further volumes of the series. Several important aspects of pattern taking and making are explored in the article, including the use of X-radiography and the testing of patterns by the construction of toiles. [ABSTRACT FROM AUTHOR]

Here we report recent technical advances that enable viscosity measurements in two DIA-type multi-anvil apparatus with a maximum of 250 tons and 1750 tons. We anticipate that this system will enable viscosity measurements for the pressures up to about 30 GPa. The deformation of the cell assemblies were analyzed by X-ray absorption tomography at beamline W II at DESY/HASYLAB after the high pressure runs. This analysis gave considerable insights into strategies for improving the cell assembly with the result that the optimized assemblies could be used at much higher pressures without blow-outs. We demonstrate using of X-ray transparent cubic boron nitride-anvils (single-stage DIA) and slotted carbide anvils (double-stage DIA) to make the whole melting chamber accessible for the high pressure X-radiography system. Results are demonstrated with viscosity measurements following Stokes’ Law by evaluation of X-radiography sequences taken by a camera equipped with a charge-coupled device sensor (CCD-camera) at pressures of 5 GPa as well as 10 GPa and temperatures of 1890 K. [ABSTRACT FROM PUBLISHER]

Abstract: Ion beam analysis (IBA) techniques play an important role in the field of cultural heritage. IBA was one of the first physical methods applied to archaeology in the 70s. 40years later, more than 25 accelerator laboratories were or are involved in cultural heritage applications. The advantages of the IBA techniques match very well the requirements for the analysis of archaeological or museum objects: non destructiveness, major, minor and trace element analysis, information in depth, elemental mapping… Thanks to this collected information, IBA techniques can answer archaeological and conservation questions: provenance determination, ancient technologies (fabrication, transformation, recipes…) and conservation issues. In spite of the competition with portable devices and large facilities (such as synchrotron or neutron reactors), the IBA methods keep their interest due to the possibility of associating two or three of them according to the archaeological or art issue. In this article, some examples chosen for their original approach are presented: PIXE for X-radiography, provenance of prehistoric pigments and painting characterisation. They illustrate the useful versatility of IBA for cultural heritage studies. Perspectives for further improvements are also proposed. [Copyright &y& Elsevier]

Abstract: A study has been carried out to test the possibility of measuring detailed quantitative profiles of the abundance of different inorganic elements through exploration cores of coal seams using automated energy-dispersive X-ray fluorescence (ED-XRF) core scanning instrumentation. Such an approach has potential application for rapidly determining the distribution of mineral matter in a coal seam, identifying horizons at which particular elements (such as phosphorus) may be concentrated, evaluating in detail the relationships between different elements in the coal, and maximising the data available to guide broader-scale sampling for conventional analysis programmes. Profiling was carried out on a series of segments from a 60mm diameter core of the Goonyella Middle seam in the northern Bowen Basin of Queensland, using an Itrax core scanner (Cox Analytical, Sweden). The scanning process included high resolution optical imaging, X-radiography, and ED-XRF spectroscopy covering the principal major elements, with XRF spectra being obtained at intervals of 200μm along the axis of each core. A series of calibration curves derived from separately-scanned pressed pellets of reference coals was used to determine the concentration of each element for each step in each sample, allowing a set of quantitative element profiles to be created for each core segment. These were evaluated in conjunction with the relevant X-radiographs and optical images to provide an integrated basis for assessing the variations in inorganic element characteristics through the core sections. The results were also compared to conventionally-determined chemical and mineralogical data for a representative core, to confirm the validity of the quantifications developed. [Copyright &y& Elsevier]

Abstract: A study of muddy tidal-flat sedimentation and bioturbation was undertaken in the Waitetuna Arm of Raglan Harbor, New Zealand, to evaluate the physical and biological processes that control cycling of sediment between the intertidal seabed and sediment–water interface, and also the formation of tidal flat sedimentary fabric and fine-scale stratigraphy. Cores were collected along an intertidal transect, and analyzed for sedimentary fabric, 210Pb and 7Be radiochemical distributions, and grain size. At the same locations, a new approach for time-series core-X-radiography study was undertaken (spanning 191 days), using magnetite-rich sand as a tracer for sedimentation and bioturbation processes in shallow tidal flat sediments. Sedimentary fabric consists of a shallow stratified layer overlying a deeper zone of intensely bioturbated shelly mud. Bioadvection mixes the deeper zone and contributes fine sediment to the surface stratified layer, via biodeposition. Physical resuspension and deposition of surface muds by wave and tidal flow are also likely contributors to formation of the surficial stratified layer, but physical stratification is not observed below this depth. The deliberate tracer study allowed calculation of bioadvection rates that control strata formation, and can be used to model diagenetic processes. Results suggest that the upper ∼15 cm of seabed can be fully mixed over timescales <1.75 y. Such mixing will erase pre-existing sedimentary fabric and transport buried sediment and chemical compounds back to the tidal-flat surface. Shallow biodiffusion also exists, but produces much slower and shallower mass transport. Best fits for 210Pb profiles using a diagenetic bioadvection/sedimentation model and independently measured tiered bioadvection rates suggest that sediment accumulation rates (SARs) on the tidal flat are ∼0.25 cm/y, near the low end of contemporary New Zealand muddy intertidal SARs. Frequent deposition and erosion of the surface layer demonstrates that long-term sediment accumulation captures only a small fraction of sediment deposited at any one time. Model results also suggest that our magnetite tracer method may slightly underestimate short-term shallow mixing rates (demonstrated by 7Be profiles), and slightly overestimate longer-term, deeper bioturbation rates (demonstrated by 210Pb profiles). [Copyright &y& Elsevier]