Journal for Foundations and Applications of Physics
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Crystallography and Spectral Analysis in structuring of 7,8-dihydroxy-4-Phenyl Coumarin Monohydrate
Get PDFVibrational assignments of 7,8-dihydroxy4-phenyl coumarin monohydrate have been made both in crystalline and gas phase. Infrared absorption and Raman spectra of 7,8-dihydroxy4-phenyl coumarin monohydrate have been interpreted and compared by electronic structure calculations at B3LYP using 6-311++G(d,p) basis set. Down-shifting of frequencies of O-H vibrations due to intra-molecular O-H…O hydrogen bonding as well as inter-molecular interactions with solvent molecule were resolved by NCA analysis. Sharpness of endothermic peak in TG/DTA shows the good degree of crystallinity and purity of the sample
Ambivalence of Time
Get PDFThe physical nature of Time is researched. Time is considered as a set of phenomena that can be divided into two fundamentally different, but interrelated groups (time sides). The first group is connected with the metric properties and topological concepts of space-time manifold, the integral part of which is Time. This side of time integrates it with spatial dimension. The second group includes physical properties connected with spontaneous time coordinate increment of massive particles (the flow of time). It provides the variation of systems and the development of physical processes in the environment. The difference between time and space can be seen here. Thus, time ambivalence (duality) is shown. Time ambivalence is one of the key temporology principles. It is impossible to build an adequate time theory without considering it
Generalized Wenzel equation for contact angle of droplets on spherical rough solid substrates
Get PDFApplying Gibbs’ concept of dividing surface and dividing line, the wetting of spherical droplets on spherical rough solid substrates was studied by methods of thermodynamics. Considering the influences of line tension, a generalized Wenzel’s equation for contact angle between droplets and spherical rough solid substrates is derived. Under some assumptions, this generalized Wenzel’s equation reduces to Rusanov’s equation
Application of exp(-Fi)-expansion method for Tzitzeica type nonlinear evolution equations
No full textThe idea of exp(-Fi)-expansion method is used to construct new profuse exact traveling wave solutions of Tzitzeica type nonlinear evolution equations. By means of this method, three types of exact traveling wave solutions for each Tzitzeica type equations are obtained, including the hyperbolic functions and trigonometric functions. The obtained results show that exp(-Fi)-expansion method is very powerful, effective and convenient mathematical tool for non-linear evolution equations in science and engineering
Wetting of cylindrical droplet on heterogeneous and cylindrical solid substrate
Get PDFBy methods of thermodynamics, wetting of cylindrical droplet on heterogeneous and smooth but chemically non-deformable cylindrical outer surfaces is investigated in this paper. For the three-phase system, we suppose the solid substrate is composed of two types of materials. Using Gibbs\u27s method of dividing surface, the system can be separated into six segments. On the assumption that the temperature and chemical potential are constant, a generalized Cassie-Baxter equation is derived taking the line tension effects into consideration. This generalized Cassie-Baxter equation is discussed based on some assumptions
Abundant Exact Traveling Wave Solutions of the (2+1)-Dimensional Couple Broer-Kaup Equations
Get PDFTo describe the propagation of small amplitude waves in nonlinear dispersive media, it is frequently necessary to take account of dissipative mechanisms to perfectly reflect real situations in many branches of physics like plasma physics, fluid dynamics and nonlinear optics. In this paper, the exp(−f (h )) -expansion method is employed to solve the (2+1)-Dimensional couple Broer-Kaup equations as a model for wave propagation in nonlinear media with dispersive and dissipative effects. As a result, a number of exact traveling wave solutions including solitary wave and periodic wave have been found for the equation. Some representative 3D profiles and 2D profiles for different values of variables of the wave solutions are graphically displayed and discussed
The effect of carbon content and submerged arc welding process on hardness of carbon steels
Get PDFLike heat treatment processes, manufacturing methods that require heat input, such as welding process, can cause changes in material properties. This study aims to investigate the effect of carbon content and welding process on the hardness of welded carbon steels. For this purpose, samples of ultra-low carbon interstitial free, low carbon and medium carbon steels that have similar composition but different carbon content are used. All samples are heat treated to remove residual stresses remained during the manufacturing processes. Automated submerged arc technique is used to create a weld beam on plate despite a joining process. Rockwell B scale is used for hardness measurements. Results prove that steel carbon content and welding process have an effect on hardness around the weld beam.
 
The Cosmological Redshift Manifests the Curvature and Interpreted as a Degree of Hyperbolicity of the Spacetime
Get PDFHubble’s law describes a uniformly expanding flat universe. Hubble’s law doesn`t explain why distant objects were receding fastest. There is an approximately linear relationship between redshift and distance at small scales for all the FLRW models, and departures from linearity at larger scales can be used to measure spatial curvature. Locally the spacetime is flat. For distant objects, the imprint of the curvature is significant, where the spacetime does no longer remain flat. The redshifts from such distant objects increase according to the increase in the curvature of the hyperbolic spacetime. The cosmological (gravitational) redshift can be interpreted as a degree of the hyperbolicity of the curved spacetime. The Universe is globally hyperbolic as we did prove mathematically [S. A. Mabkhout, Phys. Essays, 25, 112 (2012)]. Such a solution predicts the equation of state of cosmology P = - ????. The hyperbolic structure of the spacetime–not dark energy- causes the accelerated expansion of the universe. Thus, in our non-existing dark energy hyperbolic universe, the increase in the cosmological redshift can only account for the increase in curvature that causes such an accelerated expansion relative to the observer. We developed [S. A. Mabkhout, Phys. Essays, 26,422 (2013)] the equation of motion in the hyperbolic spacetime: that describes the speed up motion in the hyperbolic spacetime and predicts the flat rotation curve. In the hyperbolic spacetime, the free fall due to the curvature, causes the non-decreasing speed of the galaxies for large r. Thus, the Doppler redshift manifests such curvature. As an object is far distant apart, as much the spacetime appears relatively hyperbolic curved with a high redshift. Its velocity relatively appears to exceed the speed of light "c" due to the assumption of flat spacetime
Generalized Young equation for a spherical droplet inside a smooth and homogeneous cone involved by quadratic parabola
Get PDFWe thermodynamically investigate the wetting characteristics of a spherical droplet in a smooth and homogeneous cone rotated by the quadratic parabola through the mechanisms of both Gibbs’s dividing surfaces and Rusanov’s dividing line. For the triple phase system including the solid, liquid and vapor phases, the derivation of a generalized Young equation containing the influences of the line tension is successfully carried out. Additionally, we as well analyze various approximate forms for this generalized Young equation by using the corresponding assumptions
Design of Virtual Objects Using Transformation Optics
Get PDFTwo structures of virtual targets filled with metamaterials are investigated through transformation optics to tailor the specific electromagnetic fields into desired spatial patterns. One virtual structure is a square column object transformed from a dielectric cylinder and the other virtual structure is a cylinder object transformed from a dielectric square column. Because the electromagnetic parameters in the virtual objects are obtained from real objects by the method of transformation optics, the scattering fields of virtual structures are the same as those of the real objects. The numerical simulations further prove the correction of theoretical results