A theoretical study of photoionization from the outermost orbitals of Be, Mg and Ca atoms endohedrally confined in C
60
is reported. The fullerene ion core, comprised of sixty C
4+
, is smudged into ...a continuous jellium charge distribution, while the delocalized cloud of carbon valence electrons
plus
the encaged atom are treated in the time-dependent local density approximation (TDLDA). Systematic evolution of the mixing of outer atomic level with states of the C
60
valence band is found along the sequence. This is found to influence the plasmonic enhancement of atomic photoionization at low energies and the geometry-revealing confinement oscillations at high energies in significantly different ways: (a) the extent of enhancement is mainly determined by the strength of atomic ionization, giving the strongest enhancement for Be even though Ca suffers the largest mixing. But (b) strongest collateral oscillations are uncovered for Ca, since, relative to Be and Mg, the mixing causes the highest photoelectron production at confining boundaries of Ca. The study paints the first comparative picture of the atomic valence photospectra for alkaline earth metallofullerenes in a dynamical many-electron framework.
Heterostructures of two-dimensional transition metal dichalcogenides (TMDs) can offer a plethora of opportunities in condensed matter physics, materials science, and device engineering. However, ...despite state-of-the-art demonstrations, most current methods lack enough degrees of freedom for the synthesis of heterostructures with engineerable properties. Here, we demonstrate that combining a postgrowth chalcogen-swapping procedure with the standard lithography enables the realization of lateral TMD heterostructures with controllable dimensions and spatial profiles in predefined locations on a substrate. Indeed, our protocol receives a monolithic TMD monolayer (e.g., MoSe2) as the input and delivers lateral heterostructures (e.g., MoSe2–MoS2) with fully engineerable morphologies. In addition, through establishing MoS2x Se2(1–x)–MoS2y Se2(1–y) lateral junctions, our synthesis protocol offers an extra degree of freedom for engineering the band gap energies up to ∼320 meV on each side of the heterostructure junction via changing x and y independently. Our electron microscopy analysis reveals that such continuous tuning stems from the random intermixing of sulfur and selenium atoms following the chalcogen swapping. We believe that, by adding an engineering flavor to the synthesis of TMD heterostructures, our study lowers the barrier for the integration of two-dimensional materials into practical optoelectronic platforms.
The ability to model complex three dimensional geometries undergoing large deformations is frequently required in finite element simulations of industrial problems. As a result of the large ...deformations, finite elements may become excessively distorted and consequently unreliable from the numerical point of view. Remeshing must be used in order to preserve a good quality of the discretisation. An important aspect of remeshing is the transfer of history data from one mesh to another. Errors and numerical instabilities caused by this transfer can be minimised by using a consistent methodology. We concentrate here on this issue for finite-strain elasto-plasticity with and without nonlocal damage. A low-order tetrahedral element specially developed for this material behavior and free from locking and pressure oscillations is used for this purpose. The transfer strategy proposed by Mediavilla et al. (Comput Struct 84:604–623,
2006
) for a conventional element is taken as a basis and is extended for the 3D bubble enriched element. It is shown that by consistently transferring a minimum and carefully selected set of variables the simulation remains stable with minimal inconsistencies and deviations.
The present work discusses modeling issues of blanking processes. In this article the role of a new parameter in crack initiation called ‘Die to Punch corner ratio’ (RD/RP) is taken into account. ...This parameter has not been studied before. Various damage models are considered and compared, including Gurson, Shear and Goijaerts damage models. In addition, stress distributions in the die during blanking of two adjacent holes are studied. Consequently minimum acceptable gap between two adjacent holes can be obtained for various die and sheet materials, which is a valuable and to the authors’ knowledge a missing data in the die design literature. The effects of various damage criteria on the blanking parameters have been compared, which gives a better insight to the blanking process.
A crack initiation and propagation algorithm driven by non-local ductile damage is proposed in a three-dimensional finite strain framework. The evolution of plastic strain and stress triaxiality ...govern a non-local ductile damage field via constitutive equations. When the damage reaches a critical threshold, a discontinuity in the form of a crack surface is inserted into the three-dimensional continuum. The location and direction of the introduced discontinuity directly result from the damage field. Crack growth is also determined by the evolution of damage at the crack tip and the crack surface is adaptively extended in the computed direction. Frequent remeshing is used to computationally track the initiation and propagation of cracks, as well as to simultaneously maintain a good quality of the finite elements undergoing large deformations. This damage driven remeshing strategy towards fracture allows one to simulate arbitrary crack paths in three-dimensional evolving geometries. It has a significant potential for a wide range of industrial applications. Numerical examples are solved to demonstrate the ability of the proposed framework.
Introduction: One of the requirements in the formation of the economic structure in the health sector is reforming and applying new methods for budgeting and budget allocation in the health sector of ...Ministry of Health and Medical Education. The purpose of the current study which has been conducted in the units of Health Service of Gilan University of Medical Sciences is to compare Traditional Budgeting with Zero-Based Budgeting Method.
Method: The present study is characterized as applied, descriptive and analytical research that conducted in a retrospective way (financial year, 2011). The statistical population of the study is composed of all the heath centers supervised by Gilan University of Medical Sciences and Health Services. Examining the budgeting method of the studied units was carried out through reviewing the printed, electronic, and web-based documents as well as observing, and interviewing with experts. Data analysis was also conducted via Excel Software 2007.
Results: According to Zero-Based Budgeting method, 1.116 billion Rials is needed, out of which 694 billion Rials should be accounted in the rural health program, and 422 billion Rials in the urban health program. Moreover, the budget set for the health sector of the studied units was estimated to be 494 billion Rials.
Conclusion: The results of this study in the framework of the examined factors indicated that Zero-Based Budgeting method is superior to the Traditional method. Accordingly, planning for giving priority to this type of budgeting method and its implementation seem to be necessary.
A flotation column could be considered as one of the major breakthroughs in the field of mineral processing in the last decades. Due to an increase in the trend of the use of these type of cells in ...the mineral processing plants, an investigation regarding the performance of these cells was initiated. The flotation column at the Sarcheshmeh pilot plant with some modifications was restarted. When all necessary measures were taken, the possibility of using the flotation cell in the cleaner and recleaner stages was investigated. Replacing the cleaner cells by the column flotation increased the separation efficiency by 7%. When the column cell was used as recleaner and both cleaner and recleaner, an improvement of 10% was observed. It was found that using a column cell instead of mechanical cells in addition to a decrease in repair and maintenance costs could result in 76% and 83% reduction in energy cost of cleaner and cleaner-recleaner stages, respectively, at the pilot plant.
To investigate the role of the critical parameters in adaptation of proteins to low temperatures, a comparative systematic analysis was performed. Several parameters were proposed to have ...contribution to cold adaptation of proteins. Among proposed parameters, total values of residual structure states, secondary structure states and oligomeric states were alike in both psychrophilic and mesophilic proteins. In addition, our results provided new quantitative information about the trends in the substitution preference of Ile, Phe, Tyr, Lys, Arg, His, Glu and Leu with most of amino acids and substitution avoidance of Gly, Thr and Ala with most of amino acids. These findings would help future efforts propose a strategy for designing psychrophilic proteins.
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