energy relation
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2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Fei He ◽  
Jiabei Shen ◽  
Zhi Tang ◽  
Xiaomeiao Qi ◽  
Haoran Li

To get the generation mechanism and influence factors of the coal-rock electrical signal, it provides a reference for coal-rock electric signal prediction and dynamic disaster. Firstly, the law of charge energy relation is deduced by using the universal or functional relation of Newton’s law, and then coal and rock mass with different properties such as coal, granite, and sandstone are selected. Using the established test system, the influence of coal and rock electric signal is analyzed from the coal-rock temperature, coal and rock properties, coal-rock friction, coal-rock loading speed, and coal-rock load size. The chief results can be summarized as follows: in the process of coal-rock rising with temperature, the change rule of electrical signals can be divided into three stages according to the strength of electrical signals generated. The amplitudes of electrical signals generated by uniaxial compression of coal-rock mass with different properties are obviously different. Electrical signals can be generated during the friction of coal and rock. With the augment of loading speed, the electrical semaphore generated when the coal rock is about to fracture tends to be enhanced. The size of the electrical signal is not proportional to the size of the load, but the electrical signal is greatest when the rupture is imminent. The analysis of the influence factors of coal and rock electrical signals can provide a reference for the research on the generation mechanism of coal-rock electrical signals.


2021 ◽  
Vol 10 (10) ◽  
pp. 3283-3296
Author(s):  
S. Rechdaoui ◽  
A. Taakili

This work deals with the numerical solution of a control problem governed by the Timoshenko beam equations with locally distributed feedback. We apply a fourth-order Compact Finite Difference (CFD) approximation for the discretizing spatial derivatives and a Forward second order method for the resulting linear system of ordinary differential equations. Using the energy method, we derive energy relation for the continuous model, and design numerical scheme that preserve a discrete analogue of the energy relation. Numerical results show that the CFD approximation of fourth order give an efficient method for solving the Timoshenko beam equations.


2021 ◽  
Author(s):  
Joseph Schneider ◽  
McKenna Goetz ◽  
John Anderson

Recently there have been several experimental demonstrations of how concerted proton electron transfer (CPET) reaction rates are affected by off-main-diagonal energies, namely the stepwise thermodynamic parameters ΔG°PT and ΔG°ET. Semi-classical structure-activity relationships have been invoked to rationalize these asynchronous linear free energy relation-ships despite the widely acknowledged importance of quantum effects such as nonadiabaticity and tunneling in CPET reactions. Here we report variable temperature kinetic isotope effect data for the asynchronous reactivity of a terminal Co-oxo complex with C–H bonds and find evidence of substantial quantum tunneling which is inconsistent with semi-classical models even when including tunneling corrections. This indicates substantial nonadiabatic tunneling in the CPET reactivity of this Co-oxo complex and further motivates the need for a quantum mechanical justification for the in-fluence of ΔG°PT and ΔG°ET on reactivity. To reconcile this dichotomy, we include ΔG°PT and ΔG°ET in nonadiabatic models of CPET by having them influence the anharmonicity and depth of the proton potential energy surfaces, which we approximate as Morse potentials. With this model we independently reproduce the dominant trend with ΔG°PT + ΔG°ET as well as the subtle effect of ΔG°PT − ΔG°ET (or η) in a nonadiabatic framework. The primary route through which these off-diagonal energies influence rates is through vibronic coupling. Our results reconcile predictions from semiclassical transition state theory with models that treat proton transfer quantum mechanically in CPET reactivity and suggest that similar treatments may be possible for other nonadiabatic processes.


Mathematics ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 841
Author(s):  
Toshiaki Hishida

In this expository paper, we study Lq-Lr decay estimates of the evolution operator generated by a perturbed Stokes system in n-dimensional exterior domains when the coefficients are time-dependent and can be unbounded at spatial infinity. By following the approach developed by the present author for the physically relevant case where the rigid motion of the obstacle is time-dependent, we clarify that some decay properties of solutions to the same system in whole space Rn together with the energy relation imply the desired estimates in exterior domains provided n≥3.


Author(s):  
Mubarak Ali

Technology is achieving its climax, but the basic understanding of science in numerous phenomena is still required. Misconception using terms such as photon and electron exists in different areas of science. When the electron of outer ring in silicon atom executes interstate dynamics for only one cycle, it generates force and energy of a unit photon. Interstate dynamics of the electron for one forward and reverse cycles generate the overt photon having the least measured length. When the photon of suitable length interacts with the side of laterally orientated electron of an atom, it converts into heat energy. Under the approximate angle of 90º, when a photon interacts with the tip of laterally orientated electron, it divides into the bits of energy having a shape like integral symbols. In silicon atom, electrons of the outer ring execute confined interstate dynamics on exerting forces along the poles; the centre of atom acts as the reference point for electrons executing interstate dynamics and the lateral lengths of the electrons are along the north-south poles. In neutral-state silicon atom, the involved heat energy wraps around the force shaping along the tracing trajectory of electron dynamics in both forward and reverse cycles. A force is being shaped from the sides of electron not experiencing the exertions of forces. In interstate dynamics, electron of the outer ring first reaches the ‘maximum limit point’, where energy of one bit is engaged wrapping around the shaping force along its tracing trajectory. From the ‘maximum limit point’, electron completes the second half cycle dealing with relevant forces, where again energy of one bit is engaged wrapping around the shaping force along the tracing trajectory. In this way, an electron depicts the force and energy relation forming a unit photon. The shape of unit photon is like ‘Gaussian distribution of turned ends’. Under uninterrupted supply of heat energy to the silicon atom, an electron dynamics generates the photon having a shape like wave. Path independent but interstate dependent forces take over the control of electron. Hence, that electron executes dynamics nearly in the speed of light. In confined interstate dynamics, naturally viable conservative forces exert to the position-acquiring electron. A photon can be in the continuous and unending length if the electron dynamics remains uninterrupted. Having not made contact with states limiting forces at work, the changing aspect of electron recalls auxiliary moment of inertia at each point of turning. By executing electron dynamics, atoms under neutral states generate photons of different shapes, so revealing the phenomena of heat and photon energy.


2020 ◽  
pp. 2150080
Author(s):  
Radhika Chauhan ◽  
B. D. Indu

Considering the many-body quantum dynamics, the pairon Green’s function has been developed via a Hamiltonian that encompasses the contribution of pairons, pairon-phonon interactions, anharmonicities, and defects. To obtain the renormalized pairon energy dispersion, the most relevant Born–Mayer–Huggins potential has been taken into account. The Fermi surface for the representative [Formula: see text] high-[Formula: see text] superconductor has been obtained via renormalized pairon energy relation. This revealed the [Formula: see text]-shape superconducting gap with a nodal point along [Formula: see text] direction. Further, the superconducting gap equation has been derived using the pairon density of states. The developed gap equation is the function of temperature, Fermi energy, and renormalized pairon energy. The temperature variation of the gap equation is found to be in good agreement with the BCS gap equation. Also, this reveals the reduced gap ratio ([Formula: see text] for [Formula: see text]) in the limit (5–8) of the reduced gap ratio designated for high-[Formula: see text] superconductors.


2020 ◽  
Vol 24 (3) ◽  
pp. 1-10
Author(s):  
Aiman Albatayneh ◽  
Obieda Abueid ◽  
Dariusz Alterman

AbstractEnergy efficiency is one of the most widely used tools for both energy saving and environmental protection against greenhouse gases. Some energy efficiency techniques are being used to reduce energy consumption. This research focuses on optimising the relation of time and energy, where the best scenario of energy-saving for specified applications will be considered with the time required in achieving these scenarios. To implement this, we adopt two engineering applications (car and water pumps) on each application, with specific constraints and parameters to test the time energy relation. It was being found that for both applications, there is an optimum engineering scenario where the least amount of energy (using the extra time to minimise energy consumption) can be achieved while the remaining cases will consume higher energy. For instance, for a specific type of car used in this study, the optimum car speed was found to be between 65–70 km h–1; at this speed, the car consumes the least amount of energy (around 137 MJ when travelling a distance of 100 km). All the speeds less than the optimum speed will consume more energy; the same is true when the speed is increased over the optimum. For the second application using water pumps, it was found that a 1.1 kW pump is the most efficient at pumping a specific amount of water, and using higher or lower rated pumps will consume higher energy levels but correspondingly will reduce the time required to perform the same application. This research emphasised the concept that time can save energy, which is not yet covered in the literature as time value of energy when time is not an essential aspect and can be delayed without affecting the main tasks.


Author(s):  
Huda Mando ◽  
Ahmad Hassan ◽  
Sajjad Gharaghani

: In this study, novel quantitative structure activity relationship (QSAR) model has been developed for inhibitors of human 5-alpha reductase type II, which are used to treat benign prostate hypertrophy (BPH). The dataset consisted of 113 compounds-mainly nonsteroidal-with known inhibitory concentration. Then 3D structures of compounds were optimized and molecular structure descriptors were calculated. The stepwise multiple linear regression was used to select descriptors encoding the inhibitory activity of the compounds. Multiple linear regression (MLR) was used to build up the linear QSAR model. The results obtained revealed that the descriptors which best describe the activity were atom type electropological state, carbon type, radial distribution function (RDF), barysz matrix and molecular linear free energy relation. The suggested model could achieve satisfied square correlation coefficient of R2 = 0.72, higher than of many previous studies, indicating its superiority. Rigid validation criteria were met using external data with Q2 ˃ 0.5 and R2 = 0.75 reflecting the predictive power of the model. The QSAR model was applied for screening botanical components of herbal preparations used to treat BPH, and could predict the activity of some among others, making reasonable attribution to the proposed effect of these preparations. Gamma tocopherol, was found to be active inhibitor, in consistence with many previous studies, anticipating the power of this model in prediction of new candidate molecules and suggesting further investigations.


Author(s):  
Alireza Mojahed ◽  
Lawrence A Bergman ◽  
Alexander F Vakakis

Modal interactions are distinct features of nonlinear systems that can be exploited in applications such as vibration and shock mitigation, targeted (irreversible) energy transfers (TET), and acoustic/stress wave tailoring. For such applications, different types of nonlinearities, e.g. hardening, softening, smooth, non-smooth, material or geometric, have been considered. In this work, we examine the geometric nonlinearity resulting from an initially inclined element consisting of a linear spring and a viscous damper connected in parallel, having an initial angle of inclination, [Formula: see text]. Because of its inclined configuration, this element possesses strong (and doubly tunable with respect to [Formula: see text] and energy) geometrically nonlinear stiffness and damping effects, despite the linear constitutive laws governing its constituent components. First, we consider a single-degree-of-freedom linearly grounded oscillator attached to the nonlinear inclined element. Omitting dissipative effects, we investigate the frequency–energy relation of this system by employing the canonical action-angle transformation and show that, depending on the initial angle of inclination and the energy-level, the resulting nonlinearity can be tuned to be softening, hardening or a combination of both. Next, we explore the efficacy of the geometric nonlinearity to induce strong modal interactions by considering a three-degree-of-freedom lightly damped primary system that is weakly coupled to a single-degree-of-freedom lightly damped attachment with the inclined nonlinear element, subjected to impulsive excitation. Varying [Formula: see text] and the input energy, we demonstrate strong modal energy-exchanges between the modes of the primary system and the nonlinear attachment over broad energy-dependent spans of [Formula: see text]. We show that the passive self-adaptiveness of the nonlinear damping and the hardening–softening geometric nonlinearity can induce narrowband or broadband frequency TET, including high-to-low frequency energy transfers. Interestingly, over a definitive range of [Formula: see text], these modal interactions may be limited only between the nonlinear mode of the attachment and the highest-frequency linear mode of the primary system, inducing strong high-frequency targeted energy transfer to the primary system.


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