Influence of the aggregate state of the dispersed phase and ultrasonic effect on the flow of emulsions in microchannels

2017 ◽  
Vol 12 (2) ◽  
pp. 187-194
Author(s):  
A.A. Rakhimov ◽  
A.A. Valiev

The paper presents the results of hydrodynamic studies of inverse water hydrocarbon dispersions: emulsions and, prepared from it by freezing the dispersed phase, suspension. In addition to the high viscosity of the emulsion, a much higher viscosity of the carrier phase, the success of the use of invert emulsions in the oil industry is due to the dynamic blocking effect. The effect is that the flow velocity in the capillary structures and cracks decreases by 3-4 orders of magnitude, in spite of the constantly acting pressure drop. The work shows an increase in viscosity with decreasing temperature, while the degree of blocking of the emulsion is higher than that of the suspension prepared from it. The ultrasonic effect makes it possible to control the effect of dynamic blocking. The short-term effect of ultrasound makes it possible to restore the flow, while a longer exposure leads to the fact that blocking occurs even in ultrasound.

2016 ◽  
Vol 11 (1) ◽  
pp. 30-37 ◽  
Author(s):  
A.A. Rakhimov ◽  
A.T. Akhmetov

The paper presents results of hydrodynamic and rheological studies of the inverse water hydrocarbon emulsions. The success of the application of invert emulsions in the petroleum industry due, along with the high viscosity of the emulsion, greatly exceeding the viscosity of the carrier phase, the dynamic blocking effect, which consists in the fact that the rate of flow of emulsions in capillary structures and cracks falls with time to 3-4 orders, despite the permanent pressure drop. The reported study shows an increase in viscosity with increasing concentration or dispersion of emulsion. The increase in dispersion of w/o emulsion leads to an acceleration of the onset of dynamic blocking. The use of microfluidic devices, is made by soft photolithography, along with high-speed photography (10,000 frames/s), allowed us to see in the blocking condition the deformation of the microdroplets of water in inverse emulsion prepared from simple chemical compounds.


2011 ◽  
Vol 8 (1) ◽  
pp. 77-91
Author(s):  
A.T. Akhmetov ◽  
M.V. Mavletov ◽  
A.A. Valiev

In the flow in the microchannel of reverse water hydrocarbon emulsions, it is found the dynamic blocking effect. The essence of the effect is that the flow of the emulsion through the section of the microchannel stops with time, despite the permanent pressure drop. The difference of this work from previous ones is that for the experiments was prepared the emulsion of simple chemical compounds. For visualization of the structure formed in the capillary after blocking, the dispersed phase was introduced fluorescing component. It is studied and compared the rheological properties of the emulsion and formed from it in the phase transition suspension.


Author(s):  
S.S. Poolsawat ◽  
C.A. Huerta ◽  
S.TY. Lae ◽  
G.A. Miranda

Introduction. Experimental induction of altered histology by chemical toxins is of particular importance if its outcome resembles histopathological phenomena. Hepatotoxic drugs and chemicals are agents that can be converted by the liver into various metabolites which consequently evoke toxic responses. Very often, these drugs are intentionally administered to resolve an illness unrelated to liver function. Because of hepatic detoxification, the resulting metabolites are suggested to be integrated into the macromolecular processes of liver function and cause an array of cellular and tissue alterations, such as increased cytoplasmic lysis, centrilobular and localized necroses, chronic inflammation and “foam cell” proliferation of the hepatic sinusoids (1-4).Most experimentally drug-induced toxicity studies have concentrated primarily on the hepatic response, frequently overlooking other physiological phenomena which are directly related to liver function. Categorically, many studies have been short-term effect investigations which seldom have followed up the complications to other tissues and organs when the liver has failed to function normally.


Author(s):  
Florian Arendt

A test was done to see if reading a newspaper which consistently overrepresents foreigners as criminals strengthens the automatic association between foreign country and criminal in memory (i.e., implicit cultivation). Further, an investigation was done to find out if reading articles from the same newspaper produces a short-term effect on the same measure and if (1) emotionalization of the newspaper texts, (2) emotional reactions of the reader (indicated by arousal), and (3) attributed text credibility moderate the short-term treatment effect. Eighty-five participants were assigned to one of three experimental conditions. Participants in the control group received short factual crime texts, where the nationality of the offender was not mentioned. Participants in the factual treatment group received the same texts, but the foreign nationality was mentioned. Participants in the emotionalized treatment group received emotionalized articles (i.e., texts which are high in vividness and frequency) covering the same crimes, with the foreign nationality mentioned. Supporting empirical evidence for implicit cultivation and a short-term effect was found. However, only emotionalized articles produced a short-term effect on the strength of the automatic association, indicating that newspaper texts must have a minimum of stimulus intensity to overcome an effect threshold. There were no moderating effects of arousal or credibility pertaining to the impact on the implicit measure. However, credibility moderated the short-term effect on a first-order judgment (i.e., estimated frequency of foreigners of all criminals). This indicates that a newspaper’s effect on the strength of automatic associations is relatively independent from processes of propositional reasoning.


2020 ◽  
pp. 121-134
Author(s):  
S. A. Andryushin

In 2019, a textbook “Macroeconomics” was published in London, on the pages of which the authors presented a new monetary doctrine — Modern Monetary Theory, MMT, — an unorthodox concept based on the postulates of Post-Keynesianism, New Institutionalism, and the theory of Marxism. The attitude to this scientific concept in the scientific community is ambiguous. A smaller part of scientists actively support this doctrine, which is directly related to state monetary and fiscal stimulation of full employment, public debt servicing and economic growth. Others, the majority of economists, on the contrary, strongly criticize MMT, arguing that the new theory hides simple left-wing populism, designed for a temporary and short-term effect. This article considers the origins and the main provisions of MMT, its discussions with the mainstream, criticism of the basic tenets of MMT, and also assesses possible prospects for the development of MMT in the medium term.


1990 ◽  
Vol 50 (7) ◽  
pp. 801-805 ◽  
Author(s):  
L. E. Matzen ◽  
B. B. Andersen ◽  
B. G. Jensen ◽  
H. J. Gjessing ◽  
S. H. Sindrup ◽  
...  

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