The importance and benefits of joint faculties in higher education

The article studies the reforms in the educational system of the Republic of Uzbekistan on the example of joint faculties and the benefits of Double degree program

The importance and benefits of joint faculties in higher education

The article studies the reforms in the educational system of the Republic of Uzbekistan on the example of joint faculties and the benefits of Double degree program

Recommendations on reducing the shadow economy in the Republic of Uzbekistan based on the world experience

The article dwells on the types of shadow economy. The authors of the article analyse the causes of the occurrence and increase in the volume of the shadow economy. The authors of the article demonstrate how the world experience in a fight against the shadow economy is implemented in Uzbekista

Recommendations on reducing the shadow economy in the Republic of Uzbekistan based on the world experience

The article dwells on the types of shadow economy. The authors of the article analyse the causes of the occurrence and increase in the volume of the shadow economy. The authors of the article demonstrate how the world experience in a fight against the shadow economy is implemented in Uzbekista

Anatomo-histological structure of the rhizome Curcuma Longa L. (Zingiberaceae) in introduction conditions

For the first time in the conditions of an introduction of the Botanical garden of the National University of Uzbekistan named Mirzo Ulugbek is studied the anatomic-histologic structure of a rhizome of Curcuma longa L. and revealed characteristic diagnostic signs. These revealed diagnostic signs of a type can serve at identification of vegetable raw materials

STUDY OF THE PROPERTIES AND EFFECT OF NEW SURFACTANTS IN CEMENT SLURRY’S STRUCTURE FORMATION

Surface-active agents (surfactants) are widely used to improve the quality of materials and control technological processes. In this regard, a very urgent problem is the study new surfactants and creation of new compositions to improve the rheological and structure-forming properties of dispersed systems and cement slurries. To effectively solve this problem, it is necessary to investigate new surfactants in disperse systems. The purpose of this work was the study colloid-chemical properties of new surface-active derivatives of maleic acid and effectiveness for regulating structure formation in cement suspensions. Different methods for the measurements of properties and efficiency of new surfactants were used. New surfactants based on maleic acid derivatives with different numbers of ethoxy groups and carbon atoms in the alkyl chain were investigated. The obtained experimental data and correlations based on them showed that the colloid-chemical properties of the studied surfactants are closely related to the structure of their molecules. It was established that new surface-active derivatives of maleic acid are effective regulators of the structure formation of cement dispersed systems. It was shown that the introduction of new surfactants in combination with marble powder enhances the plasticizing effect and makes it possible to replace part of the binder with marble powder without reducing the final strength of the cement stone. It has been established that with an increase in the number of ethoxy groups in the molecule and the length of the carbohydrate chain, the surface activity and foaming ability of new surfactants increase. The use of modified marble powder with aqueous solutions of surfactants, lengthens the stage of initial structure formation and accelerates the subsequent process of structure formation with an increase in the daily strength of the cement stone