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P. W. Bridgman developed a method to measure the force acting on a moving piston of known area and conducted experiments on gases, liquids and solids at high pressures. He reported that there is no critical point on the freezing curve in his experiments on various materials. Researchers working in universities and laboratories in the USA, France, England, Germany, Russia, the Netherlands and other universities and laboratories have reported that there is no critical point on the melting curve at high pressures in their experiments on gases, liquids and solids with this method developed by P. W. Bridgman. The main method of research in physical chemistry is experience. The new physical chemistry is an experimental science. A real physicochemical experiment is of great importance in the study of physical laws and processes. The method and methodology applied in determining the hypothesis put forward is the most important factor. Experiments are key to propose a hypothesis and solve a problem. Although the existence of a critical point on the melting curve seems theoretically and graphically possible, P. W. Bridgman and other researchers have reported that there is no critical point. In our opinion, it is not possible to determine the existence of a critical point on the freezing curve by the method applied by P. W. Bridgman and other researchers in their experiments. With this method it was possible to determine the pressure and temperature dependent melting curve. For nearly a century, the presence or absence of a critical point on the freezing curve has been a matter of debate. In the experiments conducted by P. W. Bridgman and other researchers, it was found that there was no critical point, but it is possible to determine the existence of a critical point by the experimental results of the intermittent metastable state on the freezing curve at high pressures or by applying the geometric method depending on the thermodynamic parameters of the substance. [ABSTRACT FROM AUTHOR]

The paper discusses spectral sensitized photo processes in silver bromide caused by dyes adsorbed on the surface of silver stearate via the lightguide mechanism and a direct hit of the luminescent light from dye molecules localized near the microcrystal of silver bromide to the microcrystal of silver bromide. The paper submits an estimation of the contribution of dye molecules localized on the surface of silver stearate to overall spectral sensitization. These calculations demonstrate that the contribution of dye molecules adsorbed on the particle of silver stearate to spectral sensitization of silver stearate—silver bromide structure is comparable to the contribution of dye molecules placed on the microcrystal of silver bromide. Dye molecules localized on the particle of silver stearate allow to raise the efficiency of spectral sensitization by 40 to 60 percent.

The vibrations and stability of a plate having a finite length were considered in a flat supersonic flow, having adopted an assumption that one of the edges of the plate has a hinged support, and the other edge is free. Another support was located in an internal point of the plate and featured resilient attenuation properties. A compressive force, called the follower force, was applied within the plane of the plate in a direction tangent to the deformed surface of the plate. This way, a superficial system was forced in which two independent physical factors occurred and caused its self-excitation. Therefore the superficial system could be termed a ‘double self-excited system’. The solution of the equations of motion for the system was derived with a Laplace transformation.