Elemental Level Research Articles

Micro-PIXE studies on prehistoric chert tools: elemental mapping to determine Palaeolithic lithic procurement

This paper contributes to an understanding of the distances and choices involved in raw material procurement strategies by Upper Palaeolithic communities through a Pyrenean geo-archaeological case study. Methodologically, it involved using Particle Induced X-ray Emission (PIXE) with a focused proton beam to determine the concentration and distribution of elements in geological samples from three natural primary outcrops belonging to two geological formations outcropping in the French side of the Pyrenees. While it was not possible to distinguish the formation through reference to major and minor elements, some variations were revealed at the trace elemental level. With the aim to determine if these elements were associated with the Si matrix or to a specific inclusion, elemental maps were acquired, and the elemental composition of the identified inclusions were also determined. These chemical signatures were then compared to those generated from archaeological artefacts from sites in northern Spain as a means of reconstructing the catchment areas used by prehistoric groups for their chert procurement. The results indicate the existence of trans-Pyrenean long distance procurement strategies during the Magdalenian (13,700 to the 18,800 cal BP).

XPS investigations on the corrosion mechanism of V(IV) conversion coatings on hot-dip galvanized steel

The corrosion mechanisms of a vanadyl oxalate (VOC2O4) conversion coating on hot-dip galvanized (HDG) steel were clarified as using VOC2O4 as an alternative to chromate has not yet been examined. X-ray photoelectron spectroscopy (XPS) was utilized extensively for studying the elemental composition and doping level of coatings. Scanning Kelvin probe (SKP) technique was used to investigate the change in surface potential of HDG. Corrosion behavior of the conversion coating was investigated using electrochemical impedance spectroscopy (EIS) measurements. With 10 s of dipping, V(IV) (tetravalent vanadium) was present in coating layers at a level of 80 at% to total V while V(III) (trivalent vanadium) at a level of 20 at%. During exposure in the desiccator, partial V(III) translation to V(IV) increased V(IV) concentration to 83 at%, due to oxidation by the ambient oxygen. V(IV) has a cathodic inhibition in the corrosion of HDG. An enhanced corrosion performance of the coating was achieved by the increase in V(IV) concentration in coating layers over exposure time. Nevertheless, during neutral salt spray (NSS) V(IV) vanished and only V(III) retained a certain amount that played a major role in the corrosion inhibition of HDG.

Smart curiosity sinks node prediction mining algorithm for path optimization in wireless sensor network

As of late, data miming and handling for wireless sensor systems (WSNs) have turned into a theme of dynamic research in a few fields of software engineering, for example, the circulated frameworks, the database frameworks, and the data mining. Managing the large amounts of information and efficiently using this information in improved path optimization has become increasingly challenging. In this paper, we will demonstrate how sink node predicted and integrated for path relationships and patterns in linked data, i.e., the interdependencies between data items at the lowest elemental level. The problem of path optimization has been approached using various techniques. The path selection plays the vital role in achieving the quality of service parameter and secure communication. Considering multiple routing, the security can be enforced with various strategies. Using few parameters namely the congestion, delay and hop count would support improve the performance of the network as well as lifetime. With the motivation, an efficient smart curiosity sink node prediction mining algorithm has been presented in this paper. First, both the source and destination nodes maintain information about the routes and network conditions. Based on that a single efficient path has been selected for data transmission. On the other side, the receiver verifies the path being followed, the route available and their conditions. Using this information the delay approximation is performed to decide the legitimate of the path being selected and the traffic incur in the way. The proposed method identifies several network threats and detects the presence of the node in the route. The proposed plan improves the performance of mining data efficiency as well as increases the throughput.

Smart curiosity sink node prediction mining algorithm for path optimization in wireless sensor network

engineering, for example, the dispersed frameworks, the database frameworks, and the data mining. Dealing with the extensive sums of information and efficiently using this information in improved path optimization has become increasingly challenging. In this paper, we will demonstrate how sink node predicted and integrated for path relationships and patterns in linked data, i.e., the interdependencies between data items at the lowest elemental level. The problem of path optimization has been approached using various techniques. The path selection plays the vital role in achieving the quality of service parameter and secure communication. Considering multiple routing, the security can be enforced with various strategies. Using few parameters namely the congestion, delay and hop count would support improve the performance of the network as well as lifetime. With the motivation, an efficient smart curiosity sink node prediction mining algorithm has been presented in this paper. First, both the source and destination nodes maintain information about the routes and network conditions. Based on that a single efficient path has been selected for data transmission. On the other side, the receiver verifies the path being followed, the route available and their conditions. Using this information the delay approximation is performed to decide the legitimate of the path being selected and the traffic incur in the way. The proposed method identifies several network threats and detects the presence of the node in the route. The proposed plan improves the performance of mining data efficiency as well as increases the throughput.

SR-TXRF analysis of trace elements in whole blood and heart of rats: effects of irradiation with low and high doses

In the last decades, studies showed that the exposure to low doses of ionizing radiation of the body could sense and activate the cell signaling pathways needed to respond to any induced cellular damage. This procedure reduces cell killing compared with a single dose of high radiation dose. Damage to the vasculature can affect the function of most body organs by restricting blood flow and oxygen to tissues; however, the heart and brain are of main concern. The precise relationship between long-term health effects and low-dose exposures remain poorly understood. Biological markers are powerful tools that can be used to determine dose- response relationships and to estimate risk, especially when dealing with, the effects of low dose exposures in humans. These markers should be specific, sensitive, as well as easy and fast to quantify. Various types of biologic specimens are potential candidates for identifying biomarkers but blood has the advantage of being minimally invasive to obtain. In this study, we propose to apply total reflection X-ray fluorescence to quantify possible chemical elemental concentration (sulfer, iron, zinc, potassium and calcium) changes in blood and heart tissues of Wistar rats after total body irradiation with low (0.1 Gy) and high (2.5 Gy) doses. The fluorescence measurements were carried out at the X-ray Fluorescence beamline in the Brazilian Synchrotron Light Laboratory. The results showed that the irradiated animals with low doses have significant alterations in blood and cardiac tissue when compared with animals that received high doses of radiation. Taken together the analysis of all the elements, we can observe that the radiation induced oxidative stress may be the leading cause for alteration of the elemental level in the studied samples.

Adaptive floating node method for modelling cohesive fracture of composite materials

The cohesive element has been widely employed to model delamination and matrix cracking in composite materials. However, an extremely fine mesh along the potential crack path is required to achieve accurate predictions of stresses within the cohesive zone. A sufficient number of cohesive elements must be present within the cohesive zone ahead of the crack tip, resulting in very high computational cost and time for application to practical composite structures. To mitigate this problem, an adaptive floating node method (A-FNM) with potential to reduce model size and computational effort is proposed. An element with adaptive partitioning capabilities is designed such that it can be formulated as a master element, a refined element and a coarsened element, depending on the damage state in the progressive damage process. A relatively coarse overall mesh may be used initially, and by transforming the element configurations adaptively, the local refinement and coarsening schemes are applied in the analysis. The localized stress gradient ahead of the crack front within the refinement zone is captured by the refined elements. The refinement and coarsening operations are performed at the elemental level with fixed nodal connectivity, so that global successive remeshing in adaptive mesh refinement (AMR) techniques is avoided; this is the key difference between AMR and A-FNM. It is demonstrated that, without loss of accuracy, the present method simplifies the modelling procedure and reduces computational cost.

Being-With: From Infancy Through Philosophy to Psychoanalysis

ABSTRACTThis article introduces the conception of being-with, which arose from the work of Daniel Stern in infant observation, and is beginning to make its way into the discourses of clinical psychoanalysis. After reviewing Stern’s introduction of the term, I establish that within philosophy there exists strong support for this conception from phenomenological thinkers that promises to ground new approaches to the clinical situation. At its most elemental level, the idea of being-with has to do with one’s embodiment, with a basic constitutional element of one’s humanity, and with issues philosophers refer to as having to do with the condition of being. Several psychoanalytic uses of being-with are then reviewed, all of which reflect Stern’s uncanny sensitivity to the importance and the variety of ways of being-with others.

Effects of vacuum and ageing on Zr4/Cr3 based conversion coatings on aluminium alloys

In this study, we investigate the impact of ageing and high vacuum on existing environmentally friendly Zr4/Cr3-based conversion coatings. The freshly formed coating undergoes several changes during ageing and exposure to high vacuum. Based on the present data, we propose that the coating formed over AA6082 and AA7075 alloys is sol-gel in nature, confirmed by secondary neutral mass spectroscopy (SNMS) using the depth profiling technique. Our findings reveal that there are elemental level changes that result in shrinkage of the coating. Most Zr ions in the coating are in the solute form, with lesser number of Cr and Al ions that disappear under high vacuum over a certain period of time. The remaining Cr, Zr and O atoms exist in a gelatinous state. During ageing, there is a continuous transition of ions from solute to gelatinous state. In addition, the deposition of coating ions is directly influenced by the substrates and their constituents. The extent of dissolution of aluminium in the conversion bath determines both Zr and Cr ion deposition. For a highly alloyed metal like AA7075, the dissolution rate is disturbed by copper and zinc.

A Quantum-based Investment Philosophy

Schrodinger’s equation describes wave-particle duality and although mostly applied to matter at the atomic level, Schrodinger himself did not think it confined to the scale of atoms and fundamental particles. Indeed, current research at the Massachusetts Institute of Technology extends to how it can even describe human consciousness. The link between quantum mechanics and the classical world is actually quite clear. The classical world is just the “sum” of probabilities of the atomic world that begin to get very specific and very selective at larger scales. The elemental components of stock prices are not intuitive and cannot be visualized. But like photons with no rest mass, they nevertheless have energy, momentum, and frequency. Schrodinger's time-dependent equation describes how the state of a “particle” varies with time. It incorporates the lowest frequency of oscillation into its formulation. It tells how an operator or nature itself acts on a state which itself is a superposition of basis states. Mathematically, the equation involves a complex Hermitian acting on an eigenfunction to yield an eigenvalue. The absolute square of the eigenfunction has everything to do with probability. And it is these probabilities that are the building blocks at the elemental level that contribute to more accurate stock price forecasts. This paper suggests how both the linear and non-linear Schrodinger equations can be used in an optimal investment strategy.

A Review on Building Integrated Photovoltaic Façade Customization Potentials

Technological advancement in Building Integrated Photovoltaics (BIPV) has converted the building façade into a renewable energy-based generator. The BIPV façade is designed to provide energy generation along with conventional design objectives such as aesthetics and environmental control. The challenge however, is that architectural design objectives sometimes conflict with energy performance, such as the provision of view and daylight versus maximum power output. In innovative cases, the characteristics of conventional BIPV façades have been modified by researchers to address such conflicts through customization as an emerging trend in BIPV façade design. Although extensive reviews exist on BIPV product types, design integration, adoption barriers and performance issues, research on BIPV customization has not been reviewed as a solution to BIPV adoption. This paper seeks to review the potential of BIPV façade customization as a means of enhancing BIPV adoption. The current paper identifies customization parameters ranging from the customization category, level, and strategies, and related architectural potential along with an assessment of their impact. The findings reflect that elemental and compositional level customization using combined customization strategies provide enhanced BIPV products. These products are well integrated for both energy generation and aesthetic applications with a power output increase of up to 80% in some cases. The paper concludes that a wide range of BIPV adoption barriers such as aesthetics, architectural integration, and performance can be overcome by appropriate BIPV customization.

Supply risks associated with lithium-ion battery materials

One possibility for electrification of road transport consists of battery electric vehicles in combination with carbon-free sources of electricity. It is highly likely that lithium-ion batteries will provide the basis for this development. In the present paper, we use a recently developed, semi-quantitative assessment scheme to evaluate the relative supply risks associated with the elements used in the functional materials of six different lithium-ion battery types. Eleven different indicators in four supply risk categories are applied to each element; the weighting of the indicators is determined by external experts within the framework of an Analytic Hierarchy Process. The range of supply risk values on the elemental level is distinctly narrower than in our previous work on photovoltaic materials. The highest values are obtained for lithium and cobalt; the lowest for aluminium and titanium. Copper, iron, nickel, carbon (graphite), manganese and phosphorous form the middle group. We then carry out the assessment of the six battery types, to give comparative supply risks at the technology level. For this purpose the elemental supply risk values are aggregated using four different methods. Due to the small spread at the elemental level the supply risk values in all four aggregation methods also lie in a narrow range. Removing lithium, aluminium and phosphorous from the analysis, which are present in all types of battery, improves the situation. For aggregation with the simple arithmetic mean, an uncertainty analysis shows that only lithium-iron phosphate has a measurably lower supply risk compared to the other battery types. For the “cost-share” aggregation using seven elements, lithium cobalt oxide has a substantially higher supply risk than most other types.

Implementation of VPSC polycrystal model into rigid plastic finite element method and its application to Erichsen test of Mg alloy

A methodology on the multiscale simulation of metal forming processes is presented, which fully integrates the visco-plastic self-consistent (VPSC) polycrystal model into rigid plastic finite element method (FEM). To accurately predict the material behavior of a magnesium alloy from the microstructural level, the VPSC crystal plasticity model was used as a constitutive equation in this methodology. An optimization program VPSC-GA was developed in order to calculate the hardening parameters for each slip and twin mode of a single crystal from a couple of simple tension/compression tests. The existing constitutive equation for rigid plastic FEM is modified using the deviatoric stress components and the derivatives of them with respect to strain rate components. The stiffness matrix and the load vector were derived based on a new approach and implemented into DEFORMTM-3D via a user subroutine which handles stiffness matrix in elemental level. An application to the Erichsen tests of magnesium alloys was done and the stretch formability of two different Mg alloy sheets was analyzed using the results of both experiment and simulation.

Analysis of ischemic muscle in patients with peripheral artery disease using X-ray spectroscopy

BackgroundPeripheral artery disease (PAD) is a vascular disease caused by atherosclerosis, resulting in decreased blood flow to the lower extremities. The ankle-brachial index (ABI) is a standard PAD diagnostic test but only identifies reduced blood flow based on blood pressure differences. The early signs of PAD manifest themselves not only at a clinical level but also at an elemental and biochemical level. However, the biochemical and elemental alterations to PAD muscle are not well understood. The objective of this study was to compare fundamental changes in intracellular elemental compositions between control, claudicating, and critical limb ischemia muscle tissue. Materials and methodsGastrocnemius biopsies from three subjects including one control (ABI ≥ 0.9), one claudicating (0.4 ≤ ABI < 0.9), and one critical limb ischemia patient (ABI < 0.4) were evaluated using a scanning electron microscope and energy dispersive X-ray spectroscopy to quantify differences in elemental compositions. Spectra were collected for five myofibers per specimen. An analysis of variance was performed to identify significant differences in muscle elemental compositions. ResultsThis study revealed that intracellular magnesium and calcium were lower in PAD compared with control myofibers, whereas sulfur was higher. Magnesium and calcium are antagonistic, meaning, if magnesium concentrations go down calcium concentrations should go up. However, our findings do not support this antagonism in PAD. Our analysis found decreases in sodium and potassium, in PAD myofibers. ConclusionsThese findings may provide insight into the pathologic mechanisms that may operate in ischemic muscle and aid in the development of specialized preventive and rehabilitative treatment plans for PAD patients.

Hysteretic beam element with degrading smooth models

This work presents the development of a hysteretic beam element in the context of the finite element method, that is suitable for the inelastic dynamic analysis of framed structures. The formulation proposed is able to capture the main characteristics of hysteresis in structural systems and mainly accounts for stiffness degradation, strength deterioration and pinching phenomena, as well as for non-symmetrical yielding that often characterizes their behavior. The proposed formulation is based on the decoupling of deformations into elastic and hysteretic parts by considering additional hysteretic degrees of freedom, i.e., the hysteretic curvatures and hysteretic axial deformations. The direct stiffness method is employed to establish global matrices and determine the mass and viscous damping, as well as the elastic stiffness and the hysteretic matrix of the structure that corresponds to the newly added hysteretic degrees of freedom. All the governing equations of the structure, namely the linear global equations of motion and the nonlinear evolution equations at elemental level that account for degradations and pinching, are solved simultaneously. This is accomplished by converting the system of equations into state space form and implementing a variable-order solver based on numerical differentiation formulas (NDFs) to determine the solution. Furthermore, hysteretic loops and degradation phenomena are easily controlled by modifying the model parameters at the element level enabling simulations of a more realistic response. Numerical results are presented and compared against experimental results and other finite element codes to validate the proposed formulation and verify its ability to simulate complex hysteretic behavior exhibiting cyclic degradations.

Equipment vulnerability assessment (EVA) and pre-control of domino effects using a five-level hierarchical framework (FLHF)

The primary event, damage vector, escalation scenario and escalation network are the fundamental components of any domino effect, and in literature, quantitative risk assessment (QRA) is the main topic of investigation for such escalating accidents. However, a QRA's implementation and application are complicated, and its results are currently not very useful in industrial practice for implementing prevention, protection and control measures. In this paper, the use of an equipment vulnerability assessment (EVA) focusing on the probability of escalation scenario occurrence is suggested, which could provide a deep understanding at the elemental level, while QRA is used at the system level. Specifically, the outline, methods and programme for EVA are discussed. In addition, a five-level hierarchical framework (FLHF) is proposed to prevent and control domino effects comprehensively and systematically, which includes Level 1–Prevention of loss of containment (LOC); Level 2–Safety distance, safety inventory and layout optimization; Level 3–EVA and safety design, safety improvement; Level 4–Reengineering of layer-of-protection analysis (LOPA); and Level 5–QRA of the domino effect. The quantification and implementation of each level are also discussed in detail.

De la jerarquización funcional continua de los asentamientos a la discreta: el caso de Aragón

Se plantean primero las dificultades que entraña pasar de un modelo jerarquizado continuo a otro discreto y la necesidad de jerarquias discretas para la ordenación del territorio. Para la jerarquización funcional de Aragón se parte del modelo de Davies utilizando 117 variables (licencias fiscales). De la jerarquía continua de centralidades reales se llega a una jerarquía discretade tipo christalleriano dando una serie de pasos: mediante medidas tipificadas, eliminacidn de los municipios del área metropolitana, supresidn en el nivel elemental de índices de atracción negativa con excepciones justificadas (vía ernpírica y estadlstica), consideración de los incrementos medios de centralidad para aceptar las rupturas del "continuum", agrupamientos de niveles jerárquicos en función de una optimación del índice del vecino más próximo.

Trace element mapping of two Pyrenean chert deposits (SW Europe) by PIXE

The geochemical character of two chert formations from the Pyrenean mountain range (SW Europe) was established by PIXE analyses. While it was not possible to distinguish the formations through reference to major and minor elements, some variations were revealed at the trace elemental level. In order to determine if these elements are associated with the Si matrix or to the contents of a specific inclusion, elemental maps were acquired and the elemental composition of the identified inclusions were also determined. As a result, Sr, Ni and Zn are better represented in Montgaillard samples while Y, Hf, W and Zr are typical of Montsaunès cherts. Thanks to elemental maps it has been possible to determine that most of these characteristic elements are usually related to a specific inclusion content.

MEDIATING GROUNDS IN CHITTAGONG

The project is concerned about dualities and paired terms, problematizing how this type of ordering forms how we conceive and look at the world. More specifically, the division between rural and urban, production and domesticity are in focus. Two concepts — that of the salon and the garden — are being recognized as liminal and in-between spaces, mediating between constructed dualities. They are used as programmatic frames for two sites in Chittagong, Bangladesh; forming ground for two interventions. The interventions are a small-scale production of ceramic water filter and a seed library. The project concerns the everyday life of the people involved, residing in practices of washing, cleaning, sowing, cultivating, giving dimension, understanding and marvel to these routines and customs. The soil, the clay and in extension the ceramic element is what on a very elemental level joins the garden and the salon. They are also joined on a conceptual level by both being sites for production and sharing of knowledge, each with their own architectural articulation. They are rooted in the scale of the community, where participation is a keystone, and the architecture and its artefacts can be adjusted and modified according to the needs and creativity of its users.

Assessing the Reliability of Performance Assessment Scores: Some Considerations in Selecting an Appropriate Framework.

Assessing the Reliability of Performance Assessment Scores: Some Considerations in Selecting an Appropriate Framework.

Precious coral non‐destructive characterization by Raman and XRF spectroscopy

Precious corals are some of the most valuable living marine resources, growing and commercially exploited only in limited areas of the world, namely the Mediterranean Sea and the Northern Pacific Ocean. Their skeleton is formed by calcium carbonate crystallized in the form of calcite whereas their color is because of the presence of partially demethylated polyene pigments. Recently, Pacific corals have been included in the appendix II of CITES list, while Mediterranean corals are still excluded. Different Corallium species of Corallidae family (e.g. Corallium rubrum, Corallium elatius and Corallium secundum) collected from different locations of the Mediterranean Sea and the Pacific Ocean were analyzed by Raman spectroscopy for the characterization of the reddish pigment and by X‐ray fluorescence (XRF) for the determination of the chemical composition of their skeletons, in order to obtain molecular and elemental data with two relatively easy and non‐destructive techniques, which can be used quite steadily for authentication purposes. Raman analysis demonstrated the presence of specific vibrational bands useful to identify the colored pigments as a mixture involving methylated and demethylated polyenes such as carotenoids and parrodienes, characterized by the presence of ―CH3 groups along the polyene chain. The ratio between the Raman signal and fluorescence background was found to vary as a function of the macroscopic color of the coral, but Raman analyses resulted inadequate for distinguishing between corals having similar color but different origins. On the other side, XRF data provided reliable information for an appropriate separation between Pacific and Mediterranean corals at the elemental level. The results of this study will be of great relevance for the authentication and identification of the origin of corals in trade market by means of completely non‐destructive techniques. Copyright © 2016 John Wiley &amp; Sons, Ltd.