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Proton-Induced-X-Ray-Emission (PIXE) is a suitable technique for the elemental analysis of ancient metallic artifacts, without any deterioration of the samples. Metallography was used to determine the manufacture technique of ancient metallic artifacts. These techniques were applied to study 12 copper artifacts collected, from burial offerings of a "Señor Tarasco", discovered by Eduardo Pareyon, in "El Portal de Matamoros", Uruapan, Michoacán, in 1957.

In our work a comparative study is made of molecular dynamics and Monte Carlo methods applied to the growth of a thin Fe epilayer on an Ag substrate. This comparison centres on the physics of the computational approaches and of the results.

Electron penetration in semi-infinite Au for normal and oblique angles of incidence at energies between 0.5 and 4 keV is simulated within a Monte-Carlo frame work. The elastic scattering cross sections have been obtained from a modified Rutherford differential cross section, whereas inelastic core and valence electron excitation are calculated using the Gryzinski's expression. The dependence of the backscattering coefficient, mean implantation depth and stopping profiles on the angle of incidence has been examined. These quantities are found to be significantly enhanced as the angle of incidence becomes higher which is generally in consistent with previous simulations.

From femtosecond spectroscopy (fs-spectroscopy) of metals, electrons and phonons reequilibrate nearly independently, which contrasts with models of heat transfer at ordinary temperatures ($T>100$ K). These electronic transfer models only agree with thermal conductivity $(k)$ data at a single temperature, but do not agree with thermal diffusivity $(D)$ data. To address the discrepancies, which are important to problems in solid state physics, we separately measured electronic (ele) and phononic (lat) components of $D$ in many metals and alloys over $\sim$290–1100 K by varying measurement duration and sample length in laser-flash experiments. These mechanisms produce distinct diffusive responses in temperature versus time acquisitions because carrier speeds $(u)$ and heat capacities $(C)$ differ greatly. Electronic transport of heat only operates for a brief time after heat is applied because $u$ is high. High $D_{\mathrm{\text{ele}}}$ is associated with moderate $T$, long lengths, low electrical resistivity, and loss of ferromagnetism. Relationships of $D_{\mathrm{\text{ele}}}$ and $D_{\mathrm{\text{lat}}}$ with physical properties support our assignments. Although $k_{\mathrm{\text{ele}}}$ reaches $\sim 20\times k_{\mathrm{\text{lat}}}$ near 470 K, it is transient. Combining previous data on $u$ with each $D$ provides mean free paths and lifetimes that are consistent with $\sim 298$ K fs-spectroscopy, and new values at high $T$. Our findings are consistent with nearly-free electrons absorbing and transmitting a small fraction of the incoming heat, whereas phonons absorb and transmit the majority. We model time-dependent, parallel heat transfer under adiabatic conditions which is one-dimensional in solids, as required by thermodynamic law. For noninteracting mechanisms, $k\cong \mathrm{\Sigma }{C}_i{k}_i\mathrm{\Sigma }{C}_i/(\mathrm{\Sigma }{C}_i^2)$. For metals, this reduces to $k=k_{\mathrm{\text{lat}}}$ above $\sim$20 K, consistent with our measurements, and shows that Meissner’s equation $(k\cong k_{\mathrm{\text{lat}}}+k_{\mathrm{\text{ele}}})$ is invalid above $\sim$20 K. For one mechanism with multiple, interacting carriers, $k\cong \mathrm{\Sigma }{C}_i{k}_i/(\mathrm{\Sigma }{C}_i)$. Thus, certain dynamic behaviors of electrons and phonons in metals have been misunderstood. Implications for theoretical models and technological advancements are briefly discussed.

We have used a method for determining volume dependence of the Grüneisen parameter in the Lindemann law to study the pressure dependence of melting temperatures in case of 10 metals viz. Cu, Mg, Pb, Al, In, Cd, Zn, Au, Ag and Mn. The reciprocal gamma relationship has been used to estimate the values of Grüneisen parameters at different volumes. The results for melting temperatures of metals at high pressures obtained in this study using the Lindemann law of melting are compared with the available experimental data and also with the values calculated from the instability model based on a thermal equation of state. The analytical model used in this study is much simpler than the accurate DFT calculations and molecular dynamics.

We discuss the temperature independent resistivity of s–p impurities and rare earth impurities diluted in noble hosts, using a T-matrix formulation. We take into account translational symmetry breaking and therefore a nonlocal charge potential is obtained. The effect of volume difference between impurity and host elements is also considered in the calculation. In the case of "magnetic" impurities (i.e. almost all rare earth impurities) we calculate the spin disorder resistivity, obtaining a charge potential renormalized De Gennes–Friedel spin disorder resistivity. Our numerical results describe the available experimental data quite well.

Synthesis of Cobalt nanoparticles often entails toxic and expensive physical-chemistry methods. Fabrication of pure cobalt nanoparticles (NPs) using a simple and low-cost electric arc discharge method in ethylene glycol (EG) is suggested for the first time. The effect of different arc discharge currents (10, 20 and 30 A) on the size and optical absorption of the NPs are studied. Dynamic light scattering (DLS) and UV-visible spectroscopy result indicate that at an arc current of 10 A NPs of about 92.95 nm are produced and increasing the arc current leads to larger NPs. UV-visible spectroscopy data shows that the solvent gets more and more transparent with time. Sonication proves that this effect is related to agglomeration of the NPs. Formation of the pure Co NPs are evidenced by means of X-ray diffraction (XRD) measurements which gives an average size of about 21 nm using Scherrer's relation. Magnetization measurements of the samples are carried out by Alternating Gradient Force Magnetometer (AGFM). The results demonstrate the ability of the arc discharge method for direct formation of Co NPs in EG medium.

Mechanical micromachining is a powerful and effective way for manufacturing small sized machine parts. Even though the micromachining process is similar to the traditional machining, the material behavior during the process is much different. In particular, many researchers report that the basic mechanics of the work material is affected by microstructures and their crystallographic orientations. For example, crystallographic orientations of the work material have significant influence on force response, chip formation and surface finish. In order to thoroughly understand the effect of crystallographic orientations on the micromachining process, finite-element model (FEM) simulating orthogonal cutting process of single crystallographic material was presented. For modeling the work material, rate sensitive single crystal plasticity of face-centered cubic (FCC) crystal was implemented. For the chip formation during the simulation, element deletion technique was used. The simulation model is developed using ABAQUS/explicit with user material subroutine via user material subroutine (VUMAT). Simulations showed that variation of the specific cutting energy at different crystallographic orientations of work material shows significant anisotropy. The developed FEM model can be a useful prediction tool of micromachining of crystalline materials.

On the basis of the thermal equation-of-state a simple theoretical model is developed to study the pressure dependence of melting temperature. The model is then applied to compute the high pressure melting curve of 10 metals (Cu, Mg, Pb, Al, In, Cd, Zn, Au, Ag and Mn). It is found that the melting temperature is not linear with pressure and the slope $d{T}_m/dP$ of the melting curve decreases continuously with the increase in pressure. The results obtained with the present model are also compared with the previous theoretical and experimental data. A good agreement between theoretical and experimental result supports the validity of the present model.

A Fe₂O₃ nanoflakes-based solar cell was successfully prepared by thermal oxidation of iron film on FTO glass. The short circuit current density $(J_{\mathrm{\text{sc}}})$ of the cell increased with annealing time while the open circuit voltage was saturated after 1 h. This enhancement was caused by the increased surface area of the nanoflakes and improved electron transfer through the (110) crystal plane in the Fe₂O₃-based electrochemical solar cell. The overall photovoltaic performance significantly increased with ruthenium dye, which likely suppressed carrier recombination on the Fe₂O₃ surface.

Metallic Cu nanowires have been synthesized by thermal reduction of CuO nanowires in low concentration hydrogen environment. The Cu nanowires can be formed after removing oxide group from the metal oxide nanowires within temperature range from 200${}^{\circ }$C to 500${}^{\circ }$C. These nanowires have twisted structure with 100–200 nm and average lengths of 10 $\mu$m can be obtained in optimum temperature range 300–400${}^{\circ }$C reduced for 30 min. The X-ray diffraction (XRD) pattern shows Cu peaks recognized at (111), (200) and (220). Scanning electron microscopy (SEM) images reveal the reduction temperatures strongly affect the nanowires formation. Transmission electron microscopy (TEM) images confirmed that Cu nanowires have single crystalline structures with 0.21 nm fringe spacing which correspond to (111) growth direction. The results indicate that thermal reduction of copper oxide nanowires in low concentration hydrogen environment can produce high purity and single crystalline Cu nanowires.

Based on the characteristics of secondary electron emission and the relationships among parameters of secondary electron yield $\delta$ in the low-energy range of $E_{p0}\leqq E_{p0m}\leqq 800$ eV (low-energy $\delta$), the universal formula for low-energy $\delta$ as a function of $E_{p0}$, $E_{p0m}$ and maximum $\delta ({\delta }_m)$ was deduced, where $E_{p0}$ and $E_{p0m}$ are the incident energies of primary electron and of ${\delta }_m$, respectively. From the deduced universal formula and experimental low-energy $\delta$ from metals, semiconductors and insulators, special formula for low-energy $\delta$ from metals as a function of $E_{p0}$, $E_{p0m}$ and ${\delta }_m$ and that for low-energy $\delta$ from semiconductors and insulators as a function of $E_{p0}$, $E_{p0m}$ and ${\delta }_m$ were deduced, respectively. The results were analyzed, it can be concluded that the two deduced special formulae can be used to calculate low-energy $\delta$ from metals, semiconductors and insulators, respectively.

Based on the characteristics of secondary electron emission, the former formulae for the maximum yield of metals ${\delta }_m$ and primary range in the energy range of $W_{p_0}\le 800$ eV, relation $L_1$ among secondary electron escape probability $B$, average energy required to produce an internal secondary electron $𝜀$, ${\delta }_m$, primary energy of ${\delta }_m$ ($W_{p_0})$ and parameter $R$ was deduced. On the basis of $L_1$ and the former formula for ${\delta }_m$, relation $L_2$ among mean escape depth of secondary electrons emitted from metals $1/\alpha$, atomic number $Z$, back-scattering coefficient $r$, material density $\rho$, $R$, atomic weight $A_{\alpha }$ and $W_{p_0}$ was deduced. According to the deduced $L_1$, the formula for the ratio of $B$ to $𝜀$ and experimental ratio of ${\delta }_m$ to $W_{p_0}$, relation $L_3$ among $R$, original work function $\mathrm{\Phi }$ and $r$ were empirically obtained. According to the characteristics of metal surface, $L_1$, $L_2$ and $L_3$, the formula for $1/\alpha$ as a function of $Z$, $r$, $\rho$, $\mathrm{\Phi }$, $A_{\alpha }$ and $W_{p_0}$ and that for ${\delta }_m$ as a function of $r$, $\mathrm{\Phi }$ and $W_{p_0}$ were deduced, respectively. The influences of surface change on $1/\alpha$ and ${\delta }_m$ were analyzed. Calculated $1/\alpha$ and ${\delta }_m$ were compared with the corresponding experimental ones. It was concluded that the deduced formulae for $1/\alpha$ and ${\delta }_m$ can be used to estimate $1/\alpha$ and ${\delta }_m$, respectively.

A single pulse of 0.57–1.1 kJ/0.3 g-spherical Ti-powder in size range of 30–70 μm, using a constant 450 μF capacitor, was applied to produce fully porous Ti- and W-compacts by electro-discharge sintering. Microstructure examination and hardness measurement of the porous Ti-compacts revealed that more stable necks formed with increasing electrical input energy up to 1.1 kJ. On the contrary, W-compacts using rectangular W-powders in size range of 5–15 μm are composed of solid region with micropore and porous layer with weak particle bonding indicating heterogeneous structure. These results suggest that the powder morphology plays a crucial role to control the porous microstructure.

Mesomechanical constitutive modeling is applied to modeling cumulative damage and necking. The model is applied to the description of necking in specimens under uniaxial tension, and compared with experimental results received with specimens of pure iron and Fe-2.75wt%Si alloy. The process is modeled as a change in the structure; i.e. as a successive loss of continuity of the substructure of barriers resisting plastic deformation. It is shown that this model can be used for the evaluation of continuum damage, and of the description of: (i) the stress-strain diagrams up to rupture, (ii) the effect of the length of the specimen, (iii) the development of the form of the neck and its final form at rupture, (iv) the creation of internal residual energy.

This paper investigates a treated fly ash to act as a synthetic zeolite to remediate soils polluted with heavy metals and metalloids (As, Pb, Cu, Zn, Fe, Cd and Mn). Four types of such 'zeolites' were synthesized by hydrothermal treatment of a calcareous fly ash derived from Greek lignite-fired power plants: two with excess of sodium hydroxide in a solid/liquid ratio of 50 g.L^-1, and two with excess of fly ash in a solid/liquid ratio of 100g.L^-1. Soil samples were obtained from a former mining site at Lavrion, Greece. Mobilization and transfer of metals to the retention agents was effected by using HCl aq 1M, with satisfactory results with respect to As, Pb, Cu, Mn, andCd. The great variety of metal complexes in soil was found to be of major importance for the effectiveness of the overall process. The final products were solidified either on their own, or by using additives such as lime and cement.

An unconventional nonlinear elastic theory is advocated for solids undergoing large compression as may occur in shock loading. This theory incorporates an Eulerian strain measure, in locally unstressed material coordinates. Analytical predictions of this theory and conventional Lagrangian theory for elastic shock stress in anisotropic single crystals of aluminum, copper and magnesium are compared. Eulerian solutions demonstrate greater accuracy compared to atomic simulation (aluminum) and faster convergence with increasing order of elastic constants entering the internal energy. A thermomechanical framework incorporating this Eulerian strain and accounting for elastic and plastic deformations is outlined in parallel with equations for Lagrangian finite strain crystal plasticity. For several symmetric crystal orientations, predicted values of volumetric compression at the Hugoniot elastic limit of the two theories begin to differ substantially when octahedral or prismatic slip system strengths exceed about 1% of the shear modulus. Predicted pressures differ substantially for volumetric compression in excess of 5%. Predictions of Eulerian theory are closer to experimental shock data for aluminum, copper, and magnesium polycrystals.

We present, for the first time, a rational and general method to construct pearl-like chains of platinum (Pt) clusters with cytochrome c (cyt c) as building blocks, demonstrating the great potential of cyt c for the construction of nanoscale devices. We investigate the conditions which should be fulfilled to grow pearl-like chains of Pt clusters on cyt c according to a selectively heterogeneous, template-controlled mechanism. Various mechanistic aspects of the single steps composing the metallization protocol has been addressed and discussed. The results indicate that pH and the degree of reduction reaction can be considered as the key parameters for a "fine-tuning" of the metallization procedure. The formation mechanism has been extensively studied which is extremely important for future elaboration for the preparation of better-controlled structures.

Controlling the synthesis of noble metal nanostructures with highly branched morphology to obtain specific physical and chemical properties has attracted much attention. This paper reports the synthesis of 3D Pt nanodendrites with controlled architectures (multibranched) by a simple one-pot hydrothermal reaction in the presence of fructose. At high reaction temperature, fructose not only acts as a reducing agent, but also forms a hydrothermal carbon, which, as a capping agent, is absorbed on the surface of metal nanocrystals and induces the anisotropic growth of Pt nanodendrites. The prepared Pt nanodendrites are highly porous, and have self-supported nanoarchitectures with a high surface area and a number of absorption sites for reactant molecules. The Pt nanodendrites exhibit a higher electrocatalytic activity and stability than commercial Pt/C for methanol oxidation reaction.

Various metal (iron, copper, zinc, platinum)-based nanostructures were synthesized by a simple, green, and one-pot reaction of respective metal precursor and a cucurbit[7]uril (CB7) in an aqueous alkaline mixture at room temperature. The metal nanostructures (MNS) were obtained without adding any additional traditional reducing or protecting agents and/or external energy sources. Further, we could be able to tune the size and shape of the MNS just by varying the experimental conditions such as reaction concentration. Depending on the metal salts and reaction conditions, we could be able to produce different sizes and shapes of nanostructures. For example, the diameter of the CuO and iron nanoparticles (NP) was observed as $\sim 1$nm (even $<1$nm) which suggests the inclusion mechanism. However, the particle size of zinc and platinum was over 2nm which suggests the capping mechanism for the well-dispersed nanoparticles. It is worth mentioning that the CB7 acts as both reducing and protecting agent for the preparation of various MNS at ambient conditions. This one-pot and green approach for the preparation of MNS in aqueous solution has various advantages due to its mild synthesis condition and no toxic materials were used or produced, which is an important aspect for the exploration of biomedical applications and environmental influence of several metal nanoparticles that are presently prepared in organic solvents.