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Due to high densities of energy, power, and remarkable operational efficiency of Li-on battery when in contrast to Lead-acid batteries and nickel-cadmium batteries are examples of other types of batteries. Vehicles, electronics, aircraft, and other industries are all interested in lithium-ion batteries right now. However, some critical variables, such as performance degradation under extreme driving circumstances due to temperature difference in the lithium-ion cell, limit its usefulness. As a result, it's important to decide the optimal course of action based on the consequences of heat generation on various lithium-ion cell components. This paper looked at how heat is generated and how it affects each component of a li-ion battery. An analysis of different heat-controlling systems employing various design structures in numerous techniques of cooling such as liquid convection, phase transition material, air Convection and a combination of these techniques are used. Finally, utilizing a variety of design frameworks, a summary is created [ABSTRACT FROM AUTHOR]

The present paper analyzes failure observed in polymer rods collided with a steel anvil under the Taylor cylinder impact experiments. The experimental and numerical analysis demonstrates that association of the failure patterns with the loading mode depends on the rod material. Two materials are considered in the paper, specifically, polymethylmethacrylate (PMMA) and polycarbonate (PC). Damage in PMMA rods at the Taylor tests is shown to be dominated by the shear load resulting in plastic deformation. In contrast, the major mechanism of damage in PC rods is governed by omni-directional (pressure) mode of load. Analysis of the damage in sections of the rods associated with the glass transition is also addressed in the present theoretical study. Failure in these polymers follows the traditional fracture wave mechanism for brittle glass-type materials due to load in the corresponding mode. Numerical analysis employs a two-phase model with improved inter-phase thermal balance accounting for the inter-phase mass, momentum, and heat exchanges during the glass phase transition, while damage being accumulated in time. The simulation results demonstrate a good correlation with the experimental results. [ABSTRACT FROM AUTHOR]

In the present paper we consider a phase transition in a viscous liquid in a solid skeleton near a single pipe filled with hot water. We suppose that the tube itself is part of a solid skeleton. First, we consider this physical process at the microscopic level (the characteristic pore size ε' is approximately 5-20 microns) governed by Stokes equations for incompressible viscous liquid coupled with heat equations. We also assume that the liquid in the frozen state becomes the part of the unmoved solid skeleton. Note that the boundary between the solid and liquid parts of the pore fluid is unknown (free boundary) and must be found together with the solution to the Stokes equations. The suggested mathematical model at the microscopic level is physically correct, because based on the classical Newtonian continuum mechanics. But any physically correct mathematical model at the microscopic level is practically useless due to its average size. Indeed, for the numerical implementation of any such model, a step in spatial variables of several microns is required. On the other hand-side, the problem must be calculated for domains of several tens meters. No modern supercomputers or cluster computing systems are yet capable of such computations. To make it practically valuable, we must use homogenization method, which is, roughly speaking, the mathematically rigorous approximation of the microscopic mathematical model in consideration by some macroscopic mathematical model. This part will be done in the next publication. [ABSTRACT FROM AUTHOR]

The first, and at the same time one of the most important tasks in building a predictive system is the task of analyzing the original data set. The next task is to process the data according to the purpose and objectives of the predictive system. These two tasks are often not given enough attention and, as a consequence, the developer does not get the desired result as a result of building the system. This paper discusses methods and algorithms for data analysis and processing that can help in building a predictive system. The data set from the machine learning competition "ASHRAE - Great Energy Predictor III" is used as input data. The analysis phase focuses on constructing graphs and drawing conclusions from them. The paper shows how to use graphical information to find anomalies in the data and eliminate them. Examples of graphs that provide information useful for building machine learning models are given. The data processing phase describes the transformations performed on the data. It considers the transformations that lead to positive results as well as those that lead to negative results. [ABSTRACT FROM AUTHOR]

Phase change material (PCM) has attracted much interest in thermal energy storage (TES) applications due to its large heat storage capacity. The major drawback of PCM is the leakage of container, attributed by volume change during phase transition. Thus, the aim of this work is to produce form stable phase change material (FSPCM) with no leakage. FSPCM was prepared by encapsulation of myristic acid (MA) into the nitrile rubber (NBR) latex through dip coating. The performance of FSPCM was evaluated by using leakage test and the percentage of mass loss of MA after heating was calculated. PCM coated with 60% total solids content (TSC) of NBR latex shows no sign of leakage on the litmus paper. The percentage mass loss of FSPCM after thermal cyclic test was 0.46%. Thus, produced FSPCM has potential to be utilized in TES applications. [ABSTRACT FROM AUTHOR]

Rural settlement is an integral part of human shelter, which is generally organized in an organic form, in which groups of people cluster in a community, whose large proportion of the human population survives on agriculture and related professions. With the course of fast pace development, the villages are engulfed by towns and cities. Their agricultural lands are either acquired for a handsome ransom or occupied by builders by paying a huge sum of capital to the landlords. Here comes the transition phase, where traditional living styles take place in an urban environment that neither remains rural any more, nor adopts completely urban living styles. As a result, these peri-urban villages, not only lose their identity, but also fail to generate employability. So villagers migrate to metropolitan cities. This is the need of the hour to work on the rural renaissance, economic, cultural, well-being, and social sustainability on a priority basis, in selected prototype. This paper addresses the research gap that can be bridged with a multidisciplinary approach, in which the experts from all necessary disciplines shall coordinate on one platform and work on the overall well-being with smart usage of digital methods that suggest smart solutions to achieve sustainable village life and lifestyle, as well as restore its past glorious identity to secure a place in the smart village mission. [ABSTRACT FROM AUTHOR]

The paper considers laboratory experiments on unilateral freezing of samples of dry and wet sand. Freezing was carried out in the refrigerator under the influence of a cooling thermal plate from above. Thermometry of frozen sand samples was performed. As a result, the propagation velocity of the cold wave in the samples, the movement of the freezing front and the duration of the phase transition are estimated. Mathematical modeling of the sample cooling process was also performed. [ABSTRACT FROM AUTHOR]

Actuation is essential for the development of micro/nano electro-mechanical systems and the use of shape memory materials can be a solution for such a need. These materials exhibit structural phase transformation which is associated with changes in the thermo/magnetic/mechanical properties that can be used to control the actuation in various architectures. The magnetron sputtering deposition of films from such materials allows the generation of simple and complex architectures that can be used for micro and nanoactuation. This paper details several solutions to generate micro/nano actuation in bimorph and more complex architectures, and the way to control the actuation profile as a function of the phase transformation degree in the film. [ABSTRACT FROM AUTHOR]

In this paper is presented a method for solving the interior ballistics model when is used a charge of propellant grains composed of different energetic materials and obtained through additive manufacturing. Starting from the premise that the burning of these types of propellant grains is carried out in several phases, at different moments of time and using a more vivacious propellants for secondary phases, leads to a good approximation of the ideal ballistic cycle which represents a rapid increase of the pressure up to the maximum value and maintaining it until the entire propellant charge is completely burned. [ABSTRACT FROM AUTHOR]

Aluminum-steel clad composites are used as structural elements in car bodies and chases as well as in the chemical industry due to a combination of high strength of steel, low density of Al and high corrosion resistance of both materials. An important parameter influencing mechanical properties of the composite is the microstructure of the bonding region between Al and steel layer. During manufacturing of the final product, clad sheets can be subjected to elevated temperatures which enhance diffusion between the metals. As a result, a brittle intermetallic phase, deteriorating the bond strength between steel and aluminum, forms at the interface. This paper focuses on study of the interfacial microstructure in a twin-roll cast Al-steel clad strip and its evolution during in-situ annealing in transmission electron microscope. Due to isochronal annealing above 500 °C, Al5Fe2 phase forms at the interface. Nucleation centers formed at the beginning of heating experiment expand and form continuous layer. The kinetics of the growth follows the parabolic law typical for diffusion-controlled phase transformations. [ABSTRACT FROM AUTHOR]

We had introduced a microscopic technique to obtain heat capacity peaks near first-order phase transitions in polycrystalline phase change materials (PCMs). Such PCMs are composed of a large number of segments or grains, so that the total heat capacity of a PCM is a double average of heat capacities in the individual grains. One average is over surface (or boundary) effects occurring due to interactions of grains with their surroundings, while the other average is over grain sizes. Using this approach, we were able to derive a formula for heat capacity peaks and use it to very accurately fit experimental data for three selected PCMs measured by adiabatic scanning calorimetry. The fitted values of the phase change temperature for these three PCMs were not convincing, however. In this paper we argue that the reason for this controversy stems from too a crude approximation of surface effects that was used originally. Therefore, here we propose an improvement of our technique by suggesting a more appropriate approximation that still leads to as accurate fits as the original one. We illustrate this for one of the three PCMs. [ABSTRACT FROM AUTHOR]

Shape memory alloys (SMAs) are materials that both industry and research are interested in. SMAs are materials that, after a seemingly irreversible deformation, can return to their original shape. This alloy has poor yield strength when heated below its transformation temperature and will simply deform into any new shape that it can retain. SMA changes its crystal structure and returns to its original shape when heated above its transformation temperature. Because of their superior properties such as shape memory effect (SME) and pseudoelasticity, which are related to the specific way the biocompatibility, phase transformation temperatures, corrosion resistance, high wear resistance, and high strength, SMAs can be utilized in a variety of applications. This paper focuses on the features of SMAs, such as shape memory effect and superelasticity, as well as their types, fabrication processes, and the most significant applications. [ABSTRACT FROM AUTHOR]

The fibre-reinforced composite structural members play an essential role in enhancing the strength-to-weight ratio of the structure. Smart reinforcing fibres like Shape Memory Alloy (SMA) provide an additional feature of adaptive stiffness to the structure. In this paper, SMA wire-reinforced epoxy resin composite is analyzed for change in natural frequency with respect to change in transformation temperature of SMA wires to reveal the difference in stiffness of composite beam, which is a function of change in transformation temperature from martensite to the austenite phase. The numerical study is carried out using FEA software, and the experimental validation of the same is completed. The natural frequency shift is predicted by measuring the natural frequencies of the composite for free-free boundary conditions at different transformation temperatures. The significant change in the natural frequency of composite is observed during the shift in transformation temperature, and the FEA results are close to experimental results with reasonable accuracy; thus, the proposed composite provides adaptive stiffness. [ABSTRACT FROM AUTHOR]

Many metals and alloys have a complex of mechanical properties that ensure their wide application in engineering, in particular as structural materials. This is, first of all, a combination of high plasticity with significant strength and resistance to deformation, and the ratio of these properties can be regulated in a large range using mechanical and thermal treatments of metals, as well as the production of alloys of various compositions. The structural metal materials and alloys used in engineering are polycrystalline. Their mechanical properties are practically isotropic and may differ significantly from the properties of single crystals. In this paper, the crystal structures, strength and plastic properties of iron-manganese-based alloys, as well as alloys alloyed with silicon, are determined. All experiments were carried out on the X-ray installation "dRone", at the Central Research Institute of Ferrous Metallurgy named after I.P. Bardin. Dilatometric studies to determine the temperatures of direct and reverse martensitic transformations, the Neel temperature - the temperature of the magnetic phase transition were carried out on the quartz direct dilatometer "Sinco-Rico" and the German dilatometer "Linsay". [ABSTRACT FROM AUTHOR]

It is sixty years since Cyril Stanley Smith's seminal paper describing the effects of shock loading on the structure / property behavior of metals. While numerous experimental observations have fostered the correlation of post-shock microstructural parameters, such as dislocations, point defects, deformation twins, shock-induced phase products, etc., with particular shock parameters, quantitative predictive capability of the defect generation and damage evolution in materials subjected to dynamic loading has yet to be realized. Broadly based defect generation/storage phenomenology presenting a unified view of the material structure/property aspects of shock-wave deformation for a wide range of crystal structures has proven very difficult. However, changes in design and manufacturing paradigms applied to events dominated by dynamic-loading processes have placed increased emphasis on developing physically- based predictive materials models of shock effects on materials as well as amazing innovations in in-situ shock diagnostics. In this paper, a survey of the evolution in the state-of-our-understanding of defect generation and damage evolution is discussed and thoughts on the evolving capabilities to move shock / dynamic behavior of materials research from observation to design and control is presented. Examples of how utilizing "real-time", post-mortem, and "in-situ" experimental approaches together are needed to facilitate quantification 4D processes during shock-wave loading including dislocation / defect generation, shock-induced phase transitions, and damage evolution and spallation. [ABSTRACT FROM AUTHOR]

The crystalline sample of PbNb2O6 (Lead meta niobate or PN) was grown by solid-state reaction method. The material crystallizes in an orthorhombic structure at room temperature and its phase transition temperature was confirmed by hysteresis loop studies reported in our previous paper. The dielectric relaxation properties are investigated here for this material, in a temperature range from 27°C to 600°C in the frequency range (10 – 106 Hz). A supportive study of micro-structural features of the sample has been reported to confirm the mechanism of dielectric relaxation processes and relaxation kinetics. It is concluded that the dielectric relaxations occurring at low frequency are related to the presence of space charges in association with vacancies, which are trapped at the grain boundaries. [ABSTRACT FROM AUTHOR]

The lap joint of Zincalume G550 steel is welded by Metal Inert Gas (MIG) welding and ER70S-6 filler wire. 16.5 – 17.5 v of welding voltage and 3 – 4.5 m/min of wire-speed are set in parameters under the 70 A of constant welding current. The welded specimens were cold-mounted and cut with a cutting machine and the cross-section of the joints was ground with three different abrasive papers (220,1000,2000) and etching with Ferric Chloride (FeCl3). The microstructure of the joint surface is investigated. The fine (at FZ) and coarse grains (at HAZ) are identified clearly. In experimental testing, it can be seen that high welding voltage and low wire speed produced high heat energy, which can be led to the creation high volume of perlite structure in the weld zone and the grain size of the HAZ (heat affected zone) was much bigger than FZ (fusion zone) during the MIG process. The welding voltage is a direct relationship with forming microstructure that the phase transformation increases when the welding voltage increases. However, low wire speed can be expanded the size of the weld region where the fine grains are observed. In the FZ, the perlite structure (a-Ferrite and cementite) moved between the FZ and the HAZ, and the cementite grain much formed under the high-temperature end of the FZ. [ABSTRACT FROM AUTHOR]

The paper demonstrates the necessity for Russia to review its development strategy for energy markets and ensure phased transition to energy efficient technologies. Although the Paris Climate Agreement only outlines certain guidelines, implementing its provisions will have an impact on the Russian economy. The reason is that many countries have already embarked on a journey to carbon-free solutions and prevent products that do not meet their standards from accessing their domestic markets. Applying the Paris Agreements and transiting to a low carbon - and consequently - energy-efficient economy in Russia will affect the real estate sector, in particular construction and operation of buildings, in many aspects, such as energy saving and the introduction of "green" standards. The paper analyzes the possibility of putting the Paris Climate Agreement into practice in construction and operation of buildings, highlights the problems which this implementation involves, as well as substantiates the lines in the state policy, which help promote the introduction of "green" standards in real estate. [ABSTRACT FROM AUTHOR]

In this paper we investigate the Ising model on Z² with competing interactions. In this model we consider J1 as horizontal interactions and J2 as vertical interactions where J1,J2 > 0. We prove that this model can reach a phase transition. Onsager considered the case where horizontal interaction parameter J1 and vertical interaction parameter J2 are different. For any fixed J1 and J2, he showed that below a critical temperature Tc which depends on J1 and J2, phase transition occurs using some matrix transfer method. However in this paper we will prove the existence of phase transition using contours methods introduced by Sinai. We will show that there exists a ß0 > 0 such that for ß > ß0 there exist at least two limit Gibbs distribution which leads to the phenomena of phase transition. [ABSTRACT FROM AUTHOR]

The paper presents the study of the process of deformation-induced γ → α-transformation in TRIP-steel and its effect on the strain-hardening coefficient at the macroscopic level. It is shown that a phase transformation starts with the propagation of Luders bands during the pseudo-plateau, when the strain-hardening coefficient is constant. The boundaries of Luders bands are switching autowaves of localized plasticity. After the annihilation of switching autowaves in the samples in the austenitized state, the phase transformation continues with the movement of deformation fronts of the Portevin–Le Chatelier bands, which are excitation autowaves. In this case, the strain-hardening coefficient increases to a maximum value and then decreases up to fracture. The nucleation and propagation of phase transformation fronts is confirmed by magnetic measurements. After the transition to the stage where the hardening coefficient decreases, the γ → α' phase transformation decays and is no longer the predominant mechanism of plastic flow. [ABSTRACT FROM AUTHOR]

In the paper using the molecular dynamics method, several combinations of interatomic potentials are analyzed to describe the interaction of elements of a multicomponent Al-Cu-Ni alloy. The possibility of describing martensitic transformations proceeding under conditions of thermomechanical action was investigated. The studies made it possible to construct a physically correct model of the Al-Cu-Ni alloy and to analyze some regularities of structural transformations occurring in it under mechanical action and heating. The constructed model can be used for further research using a numerical experiment. [ABSTRACT FROM AUTHOR]

In this paper, we develop the theory of nucleation and evolution of crystals during the intermediate stage of phase transformation processes in metastable melts and solutions with allowance for the Gibbs-Thomson and attachment kinetics effects. An exact analytical solution of non-linear model equations is found in a parametric form. It is shown that the distribution function represents a bell-shaped curve moving with time, and the liquid metastability reduces with time as a result of the evolution of a polydisperse ensemble of crystals in a supercooled (supersaturated) system. [ABSTRACT FROM AUTHOR]

Protection systems type thermal barrier (TBC) is widely accepted solution for increasing performance and endurance of the "hot parts"(combustion chambers, ducts, vanes, adjustable nozzles, diffuser, etc.). Thermal Barrier Coatings (TBC) are known to play a critical role in the working behavior of high temperature components of turbo engines, co generative systems, metallurgy, etc. In this sense the development of new TBC coatings resistant at high temperature, thermal shock, erosion, corrosion, etc. is proposed in this papers. There are known many theoretical studies and experiments that aim the phase transformations of ceramic materials based on zirconia, during the processes of heating and cooling, especially occurring routinely during the flight of aircraft and in particular the special conditions - take-off, in-flight engine stop, landing failure, etc. The cooling processes of ceramic layers are associated with phase changes from tetragonal to mono-clinic zirconia in relation to the intensity of the processes (time, gradient) and consequent exfoliation of TBC. For stabilization of tetragonal and cubic structures at room temperature, to zirconia are added metallic oxides such as CaO, MgO, ScO3, Y2O3, or other dopant type Yb2O3, Er2O3, Gd2O3 or Nd2O3. In the paper we present experimental results and investigations related to the formation of a duplex structures made of refractory Nimonic alloy type of TBC, duplex structures with bonding layer of type MeCrAlY and a ceramic coating on the basis of stabilized zirconia with CeO2 and co-doped with Y2O3. In this paper are presented techniques and associated parameters to obtain the duplex structure as well as the scanning electron microscope (HRSEM) investigations achieved. [ABSTRACT FROM AUTHOR]

Ernest Rutherford's discovery of the atomic nucleus is a landmark in science history and a century later the story behind it is well known. Generations have read of Ernest Marsden's scattering experiments and Rutherford's astonishment at the results, followed by the older man's long retreat into contemplation until the day he could announce that he "knew what the atom looked like". This paper, a commemorative presentation, reconsiders that story. The contemporaneous record is weak in some respects, indicating some need for caution in accepting details and prompting questions about why those involved did not write about it at the time. Further, the addition as context of Rutherford's ambitious program of action in atomic research at Manchester-which transformed his department-diminishes the folkloric character of the story and switches the emphasis to Rutherford's personality. In his determination to penetrate the secrets of the atom this "battleship of physics" left little to chance. [ABSTRACT FROM AUTHOR]

International Temperature Scale-1990 (ITS-90) is formulated based on various phase transition temperatures of high pure substances to cover the temperature range from 0.65 K to 1357.77 K (-272.5 °C to 1084.62 °C), where kelvin is defined on triple point of water (TPW) at 273.16 K and the higher defined fixed point is freezing point of copper at 1357.77 K. To extend the temperature scale at higher temperatures, metal-carbon eutectic fixed points are extensively being developed as the reference standards upto 3000 °C for thermometry and radiometry applications. The assignment of the eutectic melting transition temperatures to these metal-carbon eutectics is challenging as the melting plateaus are not as flat and wide as the conventional high pure metal fixed points. This paper presents the method to determine eutectic melting transition temperature by calculating inflection point for Fe-C and Co-C eutectic fixed point cells developed at CSIR-NPL, the national metrology institute (NMI)of India. The noble metal Type-S thermocouple calibrated on ITS-90 fixed points was used to measure and determine the melting transition temperatures of Fe-C and Co-C cells, and the associated uncertainties in determination of transition temperatures were evaluated. [ABSTRACT FROM AUTHOR]

As well known, when many alkali halides, for example NaCl, KCl or RbCI, are subjected to high pressure, phase transformation take place in them with a marked decrease in specific volume and reconstruction of the crystal lattice from the NaC1-type to the CsC1-type structure (B1 to B2). This work is undertaken the effect of pressure on the crystal structure with incorporating effect of temperature for the first time. An effective interionic interaction potential (EIOP) includes long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach with modified ionic charge. In this paper effect of temperature on phase transition make the EIOP model more suitable for calculating B1 to B2 phase transition. [ABSTRACT FROM AUTHOR]

In this paper, we present the experimental analysis of the parameter T (temperature) as a function of the cumulative number nc of π– - mesons, K0 - mesons and protons produced in π– C interactions at 40 GeV/c. On the basis of this analysis, we determined a dependence between the half mass of the particle (mi/2) and the target mass value (mc = mpnc), which is required from the target for the production of the particle. We suggest that the dependence between the two masses mentioned above may be related to the beginning of the mixed phase with constant temperature. [ABSTRACT FROM AUTHOR]

The most prominent failure in electronic devices is due to excessive heating of the device during its operation. And the modern trend of miniaturization of electronic devices with better performance and features further extends the need for a proper cooling system. The phase change material (PCM) cooling technique is one of the most economical passive cooling methods which avoids mechanical vibration of the cooling system and provides stable cooling with repeated uses. This review paper presents the thermo-physical properties of commonly used PCMs and different types of thermal conductivity enhancers (TCE) for electronic devices. The findings of this literature consisting of both experimental and numerical works can be used as a guideline for future researches in this field. Heat transfer enhancement in PCM can be achieve using fins, porous media, mixing with carbon additives, microencapsulation of PCM, and by adding nanoparticles. For heat sink with fins, the volume fraction of the PCM and TCE is found to be directly affecting the performance of the cooling system. Also, distributed pin fins, the pattern of arrangement, shape, and size of the fin affects the heat transfer to the PCM. Microencapsulation also increases the heat transfer surface area of PCM. However, the selection of shell material and the core material is important to obtain the targeted thermal properties. Also, metal and metal oxide nanoparticles can significantly increase the heat conduction and diffusion capacity of the PCM. But, each of these enhancement methods has certain demerits which constantly required to be addressed to achieve a more efficient cooling system for modern electronics. [ABSTRACT FROM AUTHOR]

The paper considers the change in the volumetric gas content, the formation of hydrate and the dynamics of pressure waves during its propagation in a channel with a variable cross-section containing water and a hydrate-forming gas Freon-12, and also considered the case of variable volumetric gas content in the channel during this process. Initially bubbly liquid is under pressure P0. Further, the pressure in the system suddenly rises to the value of Pe, after which a pressure wave of a stepped profile propagates through it to the creation conditions for the hydrate formation during its propagation in a narrowing channel was shown, without taking into account the processes of fragmentation of gas bubbles and the presence of surfactants. Also shown is the change in the amplitude of the pressure wave due to the formation of gas hydrate. In addition to changing the geometry of the channel, the paper also considers the case with a change in the volumetric gas content, due to the fact that the liquid increases its acoustic elasticity. The intensity of the gas phase transition in the work is described on the basis of the theory of nonequilibrium phase transitions in vapor-liquid systems. [ABSTRACT FROM AUTHOR]

Piezoelectric ceramics possess polarization under stress and ferroelectric is a subcategory of piezoelectric which possess spontaneous polarization, phase transition, permittivity, electrical and optical characteristics beneficial for energy storage devices, capacitors, memories, sensors, generators and numerous other applications. Perovskite is the most important and appreciable class of ferroelectrics having structure 퐴퐵푂3. Here we described the structure, formation and application of some perovskites [e.g퐵푎푇푖푂3(BTO), 퐵푎(푆푟푥푇푖1−푥)푂3(BST), 푆푟푇푖푂3(STO), 푃푏푇푖푂3(PT), 푃푏(푍푟푥푇푖1−푥)푂3 (PZT)] which exhibits piezo, pyro and ferro-electricity. In this paper we will discuss the use of these perovskite structure in the fabrication of thin and thick film form by sol-gel synthesis, spin coating, chemical solution decomposition, sintering and milling utilized in detection of gas, light,humidity, temperature and pressure sensor-based application in detail. [ABSTRACT FROM AUTHOR]

In this paper we have investigated the Bianchi type-II cosmological model with variable parameters in the frame work of modified f(R,T) gravity theory as suggested by Harko et al. (Phys. Rev. D, 84:024020). As we know that the effect of space-time curvature upon phase transition is an expanding universe. In this communication we have constructed a cosmological model of the universe by taking suitable assumptions along with string in presence of magnetic field. It is to be noted that our procedure for solving the field equations is different from other authors as we have consider the time dependent deceleration parameter (DP), it means that the universe which was decelerating in the past is accelerating at present time. We found that the universe is decelerating for q>0 and accelerating for-1q≤q<0, which shown signature flipping. [ABSTRACT FROM AUTHOR]

Computer modeling of crystal growth processes is often associated with complex numerical calculations. Results of such calculations cannot always be predicted. In some cases, features of mathematical methods of calculation in conjunction with assumptions of mathematical models can lead to the appearance of unexpected results. Such results on the one hand will be correct from a mathematical point of view, but on the other hand they will not have physical justification and experimental confirmation. Obviously, in such cases it is necessary to carefully process the results obtained taking into account the physical meaning and to avoid false conclusions. And it is especially important to take this into account in the case of large-scale high-performance simulations. Earlier, high-performance computational algorithm for the modified phase field crystal model (MPFC) of crystal growth were formulated and the results of some three-dimensional simulations are obtained. In current paper we present some unstable results of simulations by the MPFC and discuss such a phenomenon. [ABSTRACT FROM AUTHOR]

In this paper, microstructure evolution and mechanic properties of metastable near Ti-5553 alloy were investigated. SHPB, SHTB and light gas gun were employed to carry out the dynamic loadings. Microstructure evolution were characterized by OM, quantitative metallography and XRD. The experimental results demonstrated that stress-induced martensite transformation occur in metastable Ti-5553 alloy through SHPB, SHTB and plate impact loadings. In SHPB loading test, stress-induced martensite transformation is one of the methods that dissipate energy besides of adiabatic shear band, and also occur before ASB. In SHTB and SHPB+SHTB loading tests, the transformation amount of stressinduced martensite exhibit similar trend. In plate impact experiment, the content of martensite phase transformation increased with the impact velocity. [ABSTRACT FROM AUTHOR]

The paper is related to the investigation of scoliosis. To choose a proper way of surgical interference in severe cases, one should predict the future evolution of the spine. For this purpose, we suggest a mathematical model based on using of the nudged elastic band method (NEB) from phase transitions physics. An example of the method application to the model of three-vertebra system is considered. [ABSTRACT FROM AUTHOR]

In this paper we investigate the problem of phase transition for Ising model on a semi-infinite Cayley tree of third order with inhomogeneous left, middle and right parameters describing the strength of the interactions between left, middle and right nearest-neighbors respectively. We produce a recurrent equation that describes a limit behavior of the sequence conditional Gibbs measures and prove that if at least two of the parameters are positive one can reach phase transition. [ABSTRACT FROM AUTHOR]

In the last few decades the alkali halides emerged as crystals with useful applications and their high-pressure behaviour is the most intensively studied subject in high-pressure physics/chemistry, material science, and geosciences. Most alkali halides follow the B1 (NaCl-type)→B2 (CsCl-type) phase-transition route under pressure. In the present paper, we have investigated the characteristics of structural phase transition that occurred in Lithium Florid compound under high pressure. The transition pressure of B1-B2 was calculated using an effective interionic interaction potential (EIOP). The changes of the characteristics of crystals like, Gibbs free energy, cohesive energy, volume collapse, and lattice constant are calculated for the B1 and B2 structures. These data were compared with the available experimental and theoretical data. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis of transparent thin films of zirconium oxide (ZrO2) deposited on glass substrates by sol-gel dip coating technique. Synthesized films were characterized for different annealing time and withdrawal speed. Change in crystallographic properties of thin films was investigated by using X-ray diffraction. Surface morphology of transparent thin films was estimated by using scanning electron microscope. [ABSTRACT FROM AUTHOR]

A thermodynamic graphical depiction known as an enthalpy-entropy (H-S) diagram depicts changes in a substance's enthalpy (H) and entropy (S) while it goes through a physical or chemical transition. The vertical axis shows the enthalpy, which is the heat content of the system under constant pressure, and the horizontal axis represents entropy, which is a measure of the degree of disorder or unpredictability of a system. Phase changes, chemical reactions, and heat transmission are just a few examples of the different thermodynamic processes that may be studied and understood using the H-S diagram. The efficiency of energy conversion procedures like power cycles and refrigeration cycles may also be ascertained using the diagram. [ABSTRACT FROM AUTHOR]

Material extrusion-based additive manufacturing, strictly speaking of the Fused Filament Fabrication (FFF), is characterized by using a thermoplastic polymer in form of a solid filament as a built material. The filament partially melts inside of a heated hotend and is subsequently extruded under the pressure generated by the filament feeding force of the feeding rollers. The processes in the heated extrusion channel are complex and difficult to model, as the melt properties are a nonlinear function of temperature and shear rate. Moreover, there is a phase transition from solid filament to liquid melt. In this paper, the required feeding force and resulting extrudate temperature at the nozzle outlet at different feeding rates, liquefier temperatures and nozzle geometries of two acrylonitrile-butadiene styrene (ABS) and polypropylene (PP) materials were investigated. For a better understanding of the melting process in the hotend, the degree of melting of the strands was determined via dead-stop experiments at selected operating points. Two process windows could be identified: At low feeding rates, the feeding force increases linearly with increasing velocity, and at a certain point, the force increases rapidly and fluctuates. The melting investigations showed that this is related to the increasingly unmolten material reaching the nozzle outlet. The semi-crystalline PP showed a smaller processing window for stable flow compared to ABS and lower extrudate temperatures due to its differentiated cp progression at the phase transition. Based on the experimental studies, Computational Fluid Dynamics (CFD) simulations were performed to predict the pressure and temperature distributions inside the channel. For modelling the shear-dependent viscosity the Carreau model was used, while the temperature dependency was described by a jump function with a solid viscosity of 106 Pa.s. It is shown that the numerical model can predict the feeding force with good accuracy and represent the change between process windows at increasing speeds. [ABSTRACT FROM AUTHOR]

The aim of this paper is to introduce a novel method for the detection of coarse water droplets in a low pressure part of steam turbines. The photogrammetry method has been applied for the measurement of coarse droplets in the low-pressure part of a steam turbine. A new probe based on this measurement technique was developed and tested in the laboratory and in a steam turbine in the Počerady power-plant. The probe was equipped with state-of-the-art instrumentation. The paper contains results from laboratory tests and the first preliminary measurements in a steam turbine. Possible applications of this method have been examined. [ABSTRACT FROM AUTHOR]

This paper reveals the structural information of lithium hydride (LiH) at high pressure. The model potential incorporate coulomb interaction potential, short range interaction and van der Waal's attraction energy within the Hafemeister and Flygare approach and the potential term as effective interionic potential model. Values obtained via this technique for LiH, revealed successful phase transition from B1 or NaCl to B2 or CsCl, The estimated transition pressure is 200 GPa, which is quite consistent with the previously available data from different theoretically techniques. [ABSTRACT FROM AUTHOR]

In the present paper, we have investigated pressure dependent structural phase transition and associated volume collapse at transition in Iron silicide (FeSi) through effective inter-ionic potential method. It has been shown that by applying an effective interionic interaction potential, which includes the long-range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction up to second neighbor ions within the Hafemeister and Flygare approach provide successful evaluation of equation of state for change in volume with respect to the applied pressure. The phase transition pressure (Pt) at 13GPa is reported for FeSi, which is consistent with the available experimental data. This transition corresponds to transformation of B1(NaCl) type structure to B2(CsCl) type structure and is a first order phase transition. This first order phase transformation showed a volume collapse of FeSi is 10.2% at 13GPa. In addition, we have also predicted pressure dependent structural phase transition and volume collapse of 1wt% silicon doped Iron alloy (Fe0.91Si0.09) is 10.91% at 16 GPa. [ABSTRACT FROM AUTHOR]

Precipitated calcium carbonate (PCC) is also known as synthetic calcium carbonate. In this paper, PCC was synthesized from carbide lime, which is the by-product from acetylene gas industry. The method used to produce PCC from carbide lime waste was ionic sucrose precipitation technique. The experiments were performed by varying the stirring rate. In this technique, carbide lime was first dissolved in ionic sucrose solution and then chilled at 10 °C for 24 hours before carbon dioxide gasses was introduced into the solution. The carbonation and precipitation process was took place and PCC was formed. The PCC was further filtered to obtain the solid PCC. The sample was then further characterised by using FESEM and XRD to determine the morphology and to identify the phase that exists in the synthesized compound respectively. The XRD and FESEM results clearly shown that the PCC obtained has mixed phases of calcite and vaterite, with mixtures of spherical and irregular shape morphologies formed. The irregular shapes corresponded to vaterite formation, meanwhile spherical shapes corresponded to calcite formation. [ABSTRACT FROM AUTHOR]

Measurement of the surface residual stress in a flat hot rolled steel strip using strain gauge method is considered in this paper. Residual stresses arise in the flat strips when the shear cut and laser cut is applied. Bending, twisting, central buckled and edge waviness is the common defects occur during the cutting and uncoiling process. These defects arise due to the non-uniform elastic-plastic deformation, phase transformation occurring during cooling and coiling-uncoiling process. The residual stress analysis is very important because with early detection it is possible to prevent an object from failure. The goal of this paper is to measure the surface residual stress in flat hot rolled strip using strain gauge method. The residual stress was measured in the head and tail end of hot rolled strip considering as a critical part of the strip. [ABSTRACT FROM AUTHOR]

This paper presents a procedure for the implementation of control algorithms for hardware-bit compatible with the standard IEC61131-3. The described transformation based on the sets of calculus and graphs, allows translation of the original form of the control program to the form in full compliance with the original, giving the architecture represented by two tick. The proposed method enables the efficient implementation of the control bits in the FPGA with the use of a standardized programming language LD. [ABSTRACT FROM AUTHOR]

Examined at the macro-scale, fluidized beds may appear to behave like a solid, a liquid or a gas, depending on the magnitude of the applied superficial gas velocity. Using DEM simulations, the paper examines the different types of behavior as the gas velocity is increased to cover the complete range from fixed bed to homogeneous expansion, bubbling, turbulent and fast fluidization. The paper highlights the transitions between the various regimes. [ABSTRACT FROM AUTHOR]

A generalized non local-equilibrium, three-equation model was developed for the macroscopic description of two-phase flow heat and mass transfer in porous media subjected to phase change. Six pore-scale closure problems were proposed to determine all the effective transport coefficients for representative unit cells. An improved model is presented in this paper with the perspective of application to intense boiling phenomena. The objective of this paper is to present application of this model to the simulation of reflooding of severely damaged nuclear reactor cores. In case of accident at a nuclear power plant, water sources may not be available for a long period of time and the core heats up due to the residual power. Any attempt to inject water during core degradation can lead to quenching and further fragmentation of the core material. The fragmentation of fuel rods and melting of reactor core materials may result in the formation of a "debris bed". The typical particle size in a debris bed might reach few millimeters (characteristic length-scale: 1 to 5 mm), which corresponds to a high permeability porous medium. The proposed two-phase flow model is implemented in the ICARECATHARE code, developed by IRSN to study severe accident scenarios in pressurized water reactors. Currently, the French IRSN has set up two experimental facilities to study debris bed reflooding, PEARL and PRELUDE, with the objective to validate safety models. The PRELUDE program studies the complex two phase flow of water and steam in a porous medium (diameter 180 mm, height 200 mm), initially heated to a high temperature (400°C or 700°C). The series of PRELUDE experiments achieved in 2010 constitute a significant complement to the database of high temperature bottom reflood experimental data. They provide relevant data to understand the progression of the quench front and the intensity of heat transfer. Modeling accurately these experiments required improvements to the reflooding model, especially in terms of the existence of various saturation regimes. The improved two-phase flow model shows a good agreement with PRELUDE experimental results. [ABSTRACT FROM AUTHOR]

I have known Predhiman for quite some time and I consider his friendship a great privilege. He along with some of his colleagues made the almost unique transition time to time from Quantum Electrodynamics of his (almost classical) electromagnetic plasma to Quantum Chromodynamics of quarks and gluons. Some of the papers are unique in the sense they surface up to the centre stage of the field of quarks and gluons giving us a new insight [1-4]; the particular paper of Bannur and Kaw discussing the stability of quark gluon plasma is a particularly interesting one. I wish Predhiman the very best on this occasion and sincerely hope for a long vital and fruitful life that lies ahead. Interestingly enough this transition from QED (electromagnetic plasma) to QCD plasma (Quark Gluon Plasma) was motivated by consuming a very special kind of Indian soft nuts on Sunday afternoons, the consumers consisted of two persons, P. K. Kaw and Jitendra Parikh-some nuts! [ABSTRACT FROM AUTHOR]

Experimental study on stopping power of ferroelectric Tryglycine Sulphate (TGS) single crystal for 24.779 MeV protons was carried out as a function of the temperature of TGS with an accuracy of 0.05%. The stopping power of the TGC crystal shows broad valleys in ferroelectric region when the proton beam is moving along the ferroelectric b-axis (010). The fluctuations with peak-peak variation of 0.3% - 0.6% for proton beam near the Curie temperature TC is observed. This variation in the ferroelectric region cannot be contributed to the dielectric constant of the medium. The electric field and the localized temperature due to passage of proton beam may cause the switching and pining of the domains. The domain switching time τs depends on the transverse electric field and sample thickness. The thermal spike model is used to estimate the increase in the localized temperature due to passage of 24.779 MeV Protons in ferroelectric TGS crystal. In this paper, the experimental method of measuring stopping power of TGS crystal for proton beam, interpretation of the results in terms of (i) increase in localized temperature of the crystal sample using thermal spike model, (ii) the transverse electric field developed in the crystal sample and (iii) the domain switching time to account the observed experimental fluctuations in stopping power of TGS crystal for proton beam is discussed. [ABSTRACT FROM AUTHOR]

In this paper we consider Ising models with competing interactions defined on semi-infinite Cayley tree of second order. Phase diagram of such models contain new modulated phases, in addition to the expected paramagnetic and ferromagnetic phase. The aim of this paper is to select phases of these models with competing interactions on Cayley tree which exhibit phase transitions and at the same time can be solved exactly. [ABSTRACT FROM AUTHOR]