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Revealing the Essence of Electric Permittivity Constant 被引量:2
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作者 Nader Butto 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第1期210-217,共8页
Electric constant believed fundamental constant determined only by physical measurement and cannot be calculated. A new theory about the origin and the essence of the electric constant is proposed and mathematical for... Electric constant believed fundamental constant determined only by physical measurement and cannot be calculated. A new theory about the origin and the essence of the electric constant is proposed and mathematical formulation is described. The vacuum is considered to be superfluid and the electric constant is described as a physical property of the “vacuum”. Hydrodynamics laws are applied to calculate the elasticity and the compressibility of the vacuum to obtain the electric constant value. Thus, electric permittivity is the expression of compressibility of the vacuum which is the capability of the vacuum to permit electric field lines. In conclusion, electric constant is not fundamental constant but observable parameter of the vacuum which depends mainly by the vacuum density. This result could have important consequences in our understanding the origin of physical forces forward Universal Unified Theory based on one constant only, the density of the vacuum. 展开更多
关键词 electric constant ELASTICITY Vacuum Compressibility Vacuum Density
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A Concept of Absolute Polarization in Dielectrics
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作者 Ishnath Pathak 《Journal of Energy and Power Engineering》 2017年第4期279-283,共5页
It is enunciated in this paper that the volume density of the dipole moment of the induced charges in a dielectric does not in general qualify as a field in terms of which the actual induced charge distribution in the... It is enunciated in this paper that the volume density of the dipole moment of the induced charges in a dielectric does not in general qualify as a field in terms of which the actual induced charge distribution in the dielectric can he expressed as a volume charge density inside the interior of the dielectric equal to the negative of the divergence of that field and a surface charge density on the boundary of the dielectric equal to the component of that field in the direction of the outward normal to the boundary, unless the induced charge density inside the dielectric vanishes. The field that qualifies to satisfy the second criterion is in the general case named "absolute polarization", and the interconnection between the two polarizations is established. It is then demonstrated that although a few major equations of linear media electrostatics change, the results for the field of a uniformly polarized object remain unchanged, and all the existing methods of analytical evaluation can be justified if the "polarization" defined by the first criterion of being a field that equals the volume density of the dipole moment of bound charges is just replaced by the "absolute polarization", the concept of which is introduced here. 展开更多
关键词 Forces and fields conductors and dielectrics in constant electric field non-uniform polarization fields.
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Effect of carboxymethyl cellulose on dissolution kinetics of carboxymethyl cellulose-sodium carbonate two-component tablet 被引量:2
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作者 Changdong Li Carlos Amador Yulong Ding 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第10期1545-1550,共6页
Sodium carbonate and carboxymethyl cellulose powders are compressed into two-component tablets with three mass ratios,97%:3%,95%:5% and 93%:7%.The dissolution tests for two-component tablets and reference pure sodium ... Sodium carbonate and carboxymethyl cellulose powders are compressed into two-component tablets with three mass ratios,97%:3%,95%:5% and 93%:7%.The dissolution tests for two-component tablets and reference pure sodium carbonate tablets are carried out at various temperatures.The dissolution process of each tablet is measured by electrical conductivity tracking method and the concentration of dissolved sodium carbonate is quanti fied with calibrated conductivity-concentration converting equation of sodium carbonate.The quanti fied dissolution data is fitted with both surface reaction model and diffusion layer model and the results clearly show that surface reaction model is suggested as the appropriate dissolution model for all measured tablets.Therefore,it is determined that carboxymethyl cellulose is a stable element to remain the dissolution mechanism of tablet unchanged.The dissolution rate constant quanti fied with surface reaction model presents that carboxymethyl cellulose-sodium carbonate two-component tablets obtain signi ficant higher dissolution rate constant than pure sodium carbonate tablet and higher proportion of carboxymethyl cellulose leads to apparent higher dissolution rate constant.The results prove for the usage of carboxymethyl cellulose in most practical applications at a relative low-level,the effect of carboxymethyl cellulose is effective and positive for two-component tablet to enhance the dissolution process and improve dissolution rate constant and this effect is speculated coming from its dynamic physical transforming process in water including dilation and conglutination. 展开更多
关键词 Carboxymethyl cellulose Sodium carbonate electrical conductivity Temperature Surface reaction model Dissolution rate constant
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Electro-spray of high viscous liquids for producing mono-sized spherical alginate beads 被引量:3
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作者 Hamid Moghadam Mohsen Samimi +1 位作者 Abdolreza Samimi Mohamad Khorram 《Particuology》 SCIE EI CAS CSCD 2008年第4期271-275,共5页
Alginate beads, often used for controlled release of enzymes and drugs, are usually produced by spraying sodium alginate liquid into a gelling agent using mechanical vibration nozzle or air jet. In this work an altern... Alginate beads, often used for controlled release of enzymes and drugs, are usually produced by spraying sodium alginate liquid into a gelling agent using mechanical vibration nozzle or air jet. In this work an alternative method of electro-spray was employed to form droplets with desired size from a highly viscous sodium alginate solution using constant DC voltage. The droplets were then cured in a calcium chloride solution. The main objective was to produce mono-sized beads from such a highly viscous and non-Newtonian liquid (1000–5000 mPa s). The effects of nozzle diameter, flow rate and concentration of liquid on the size of the beads were investigated. Among the parameters studied, voltage had a pronounced effect on the size of beads as compared to flow rate, nozzle diameter and concentration of alginate liquid. The size of beads was reduced to a minimum value with increasing the voltage in the range of 0–10 kV. At the early stages of voltage increase (i.e. up to about 4 kV), the rate of size reduction was relatively low, while the dripping mode dominated. However, in the middle part of the range of applied voltage, where the rate of size reduction was high (i.e. about 4–7 kV), an unstable transition occurred between dripping and jetting. At the end part of the range (i.e. 7–10 kV) jet mode of spray was observed. Increasing the height of fall of the droplets was found to improve the sphericity of the beads, because of the increased time of flight for the droplets. This was especially identifiable at higher concentrations of the alginate liquid (i.e. 3 w/v%). 展开更多
关键词 Electro-spray Highly viscous liquid constant DC electric field Alginate beads
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