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Nickel-Titanium (Ni-Ti) thin films have gained a lot of attention due to their unique features, such as the shape memory effect. Micro-actuators, micro-valve, micro-fluid pumps, bio-medical applications, and electronic applications have a lot of interest in these smart thin films. Sputter-deposited NiTi thin films have shown the potential to be very useful as a powerful actuator in micro-electro-mechanical systems (MEMS) because of their large recovery forces and high recoverable strains. Despite the advancement of improved deposition methods for the NiTi thin films, there are still certain unsolved challenges that impede accurate composition control throughout the deposition process. Many applications, spanning from the aerospace industries to a range of nanotechnologies, require knowledge of the sputtering characteristics of the materials that are subjected to bombardment, ejection, and deposition of ions. In recent decades, atomic scale modeling has been given a high emphasis in ion sputtering research, providing an adequate and precise description of collision cascades in solids using the Stopping and Range of Ions in Matter (SRIM) and Transport of Ions in Matter (TRIM). In this paper, SRIM is used to address how the heavy ions interact with the target materials. A variety of ion-solid interaction characteristics, including the sputter yield, have been determined by simulating collision cascades in the solids. On the other hand, TRIM was used to describe the range of ions that enter into the matter and cause damage to the target throughout the process. The simulation was carried out to compare the sputtering yield of Ni and Ti by varying the energy input (from 300V to 1300V). SRIM simulation was conducted by varying the thickness of the film, the angle of incidence of ions, and the energy involved in the sputtering process. The characterization of the films has been carried out using Field Emission Scanning Electron Microscopy (FESEM) to comprehend the surface and interface morphologies of the films and to validate the simulated results. With an increase in energy input (target voltage), the sputtering yield increased. The sputtering yield of the Ni target was higher than the Ti target indicating that Ni can be removed relatively easier than Ti.

Recently, the research on the propagation of hot events has received widespread attention. By analyzing the data of hot events and the data of the common events in the same period on the network, we found that hot events usually break out quickly and opinion leaders and cluster behaviors exist in their propagation process. At the same time, the media public opinion fields of reporting hot events overlap and promote each other. Based on the common factors that drive an event to become a hot event, we used the heat calculation formula and entropy method to put forward the propagation model of hot events based on information coupling and information energy interaction. In the model, the coupling values of different event information are quantified based on the information fragment coupling effect. The heat calculation formula is used to dynamically adjust the propagation probability of different individuals in the propagation process of hot event, and the sensational effect threshold is introduced based on the overall energy value of the event. Finally, we used the real social relationship networks to simulate the evolution propagation process of the hot events, and compared it with the crawling real propagation curve of the events. The proposed model provides a good supplement for the study of the hot events.

The ground state of semiconductor quantum rings (QRs) in the presence of an external magnetic field B is theoretically analyzed. By numerically diagonalizing the effective-mass Hamiltonian of the QRs, the energy and wavefunction of the ground state are obtained. It is found that the energy oscillates as B increases. The evolution of the angular momentum L₀ and the spin S₀ of the ground state in accord with B is revealed. We depict the geometric configuration of the ground state via density functions. Based on an analysis of the wavefunction, it is shown that each configuration is accessible only to a specific group of states having specific L₀ and S₀.

In this work, spectra of energy and fluence of neutrons produced in the conditions of deformed space-time (DST), due to the violation of the local Lorentz invariance (LLI) in the nuclear interactions are shown for the first time. DST-neutrons are produced by a mechanical process in which AISI 304 steel bars undergo a sonication using ultrasounds with 20 kHz and 330 W. The energy spectrum of the DST-neutrons has been investigated both at low (less than 0.4 MeV) and at high (up to 4 MeV) energy. We could conclude that the DST-neutrons have different spectra for different energy intervals. It is therefore possible to hypothesize that the DST-neutrons production presents peculiar features not only with respect to the time (asynchrony) and space (asymmetry) but also in the neutron energy spectra.

HIGHLIGHTS

• •Effectiveness of vice blades flow control method.
• •Improvement mechanism of flow control method on centrifugal pump.
• •Energy redistribution of multi-scale turbulence by flow control method.
• •Design strategy for high-performance centrifugal pump.

The demand for the high-performance centrifugal pumps has grown considerably in order to address various working conditions and application scenarios. Here, a high-performance centrifugal pump capable of great hydraulic and anti-cavitation performance, and low-pressure pulsation and vibration, is realized by adding drainage vice blade to the conventional blade type. The multi-scale turbulence in centrifugal pumps is characterized by the Hybrid RANS/LES method, then the energy distributions are obtained by the proper orthogonal decomposition (POD) method. The experimental methods are employed to study the pressure pulsation and vibration characteristics. The new-type of blades can reconstruct the energy of multi-scale turbulence in centrifugal pump by concentrating the energy on low-frequency large-scale flow structures, while reducing the energy of high-frequency small-scale flow structures. A higher energy of large-scale flow structures can enhance the energy transportation and hydraulic performance in centrifugal pump. The small-scale flow structures with lower energy can suppress high-frequency excitation in flow to avoid the hydraulic resonance, which is essential to improve the dynamic characteristics of the centrifugal pumps. We propose a flow control method that can reconstruct the energy distribution of multi-scale turbulence which can greatly improve its overall performance, suggesting a broad range of promising applications.

In this paper, we introduce fractal interpolation functions (FIFs) and linear FIFs on a post critically finite (p.c.f. for short) self-similar set K. We present a sufficient condition such that linear FIFs have finite energy and prove that the solution of Dirichlet problem -Δ_μ u = f,u|_∂K = 0 is a linear FIF on K if f is a linear FIF.

The aluminum-based composites (AMCs) are known for a variety of functions like building, aerospace, automotive, marine, and aeronautical applications. In this research, Al-4032 alloy-based 6% SiC (by weight) composite has been fabricated using stir casting and the effects of prominent machining parameters on energy consumption and surface finish have been examined using carbide inserts in turning. Microstructures of as-cast specimens has been analyzed using the optical microscope, scanning electron microscopy, and energy-dispersive spectroscopy. The CNC turning has been performed at varying machining parameters like cutting speed, feed rate, and depth of cut, following an RSM-based design matrix. The desirability function approach has been employed to obtain the best combination of parameters for achieving the desired objectives. The experimental outcome demonstrates that the machined composite is considerably influenced by built-up edge (BUE) formation and interfacial bonding of particles. The result establishes that the inclusion of SiC in the Al-4032 matrix demonstrates improved mechanical properties and superior machined surface with the optimized turning operation.

Zinc oxide (ZnO) electrical properties can be modified by addition of impurities or defects such as vacancies or other substances. We use sulfur (S) as a substitutional impurity and present a theoretical study on the characteristics of ZnO structures in its crystal form containing S in substitution of O. For theoretical calculations we used Density Functional Theory (DFT) with pseudopotentials and plane waves. ZnO in crystal form with S in substitution of O at heavy percentage was studied by analyzing properties like lattice characteristics, total energy, and gap energy. Lattice parameters a, b, c, and c/a ratio increase with the S-substituent percentage while the crystal stability decreases. Variation of gap energy shows a decreasing trend with increasing amount of substitution. In this paper, we provide a detailed data useful to identify the effects on ZnO in its crystal form when O is replaced by S that will help to predict if the structural changes on the modified ZnO structures may be suitable for applications in opto-electronics.

Simple theoretical method is developed to study the size dependence of equation of state of nanomaterials. The isothermal compression of Ni and ε-Fe has been computed for different particle sizes. A shift in compression curve is obtained by increasing the particle size. This demonstrates the softening of the material by increasing the particle size. For larger particle size (~100 nm) the compression curve resembles with that of the bulk. This demonstrates that the nanomaterial becomes bulk for larger particle size. The results have been compared with the available experimental data. A good agreement between theory and experiment demonstrates the validity of the method proposed in the present paper.