Papers by Keyword: Viscosity

Abstract: Through the cultivation of two polymer-producing strains of WP1, SP1, determined the suitable growth temperature of bacteria, followed by fermented, we research the growth of the strains and metabolite changes on viscosity and pH values. Results show that at 80 r/min, 120 r/min training conditions, viscosity of strain WP1 is all more than 100mPa•s, the strains of experimental works better than SP1. Therefore, selected strain WP1 identified as strains of microorganisms in thick oilfield combination flooding produced polymers, this strain is identified at last.

Abstract: High energy explosions and irradiation may cause that the minerals and mineraloids form glassy phase on the earth surface. We would like to determine the mechanical properties of these glassy materials. To achieve this and manufacture samples we need to measure the main technological property, the viscosity.

Abstract: The present paper describes the results of the physicochemical and rheological characterisation of the selected self-made solutions of synthetic saliva. The substitutes of the used saliva were prepared on the basis of gums (xanthan, guar, arabic and carob bean) dissolved in saline buffer. Additionally, one of preparations were composed of xanthan gum and sodium dodecyl sulphate (SDS). The analysis of the viscosity, pH, surface tension and conductivity of the tested solutions was performed. The tests were carried out following one, three and seven days. The obtained results of the conducted studies showed differences between the tested preparations in the scope of the above evaluated quantities. The preparations based on the tested gums have similar properties in terms of pH, surface tension and conductivity. Only the substitute with the addition of xanthan gum and SDS exhibited different characteristics: the highest value of pH and the lowest values of conductivity and surface tension. In the case of viscosity, some preparations exhibited Newtonian rheological characteristics while others exhibited non-Newtonian characteristics.

Abstract: In this article, corn starch was modified by α-amylase with different hydrolytic time (30, 60, 90 and 120 min) and the effects of modification technology on its properties of viscosity, compound structure and mechanical were studied. The result showed that structure of modified starch was conserved with hydrolytic time increased, whereas tensile strength were increased and viscosity was decreased. The performance of modified starch that hydrolyzed by 30 min was better than others and pinholes were generated in the surface of starch granules

Abstract: Foamed epoxy asphalt, which is a kind of epoxy asphalt with a brand-new curing system, has excellent construction performance. Based on the change of viscosity-temperature curves, several mixing amounts of new anhydride curing agents used in B-component of epoxy asphalt have been proposed. Through adjusting the content variation of B component to make the viscosity meet curing conditions. Meanwhile, the curing system formula has been improved by monitoring the viscosity change in the curing process, which can effectively slow down the curing reaction, make the performance of foamed epoxy asphalt achieve the construction requirements, and also provide enough time to complete mixing, paving and rolling in the process of construction. Material A1, A2, N1, and American ChemCo epoxy asphalt was studied by viscosity tests.

Abstract: In this study, Cu-H₂O nanofluids with different mass fraction and nanoparticle size were prepared by supersonic oscillator through appending hydrophilic dispersant into deionized water. The viscosities of Cu-H₂O nanofluids and H₂O were investigated experimentally under different temperature. The experimental results show that the viscosities of nanofluids increase apparently compared to the deionized water, and increases with increasing nanoparticle size, mass fraction. What’s more, the viscosity of nanofluids decreases with increasing temperature. The results also demonstrated that the Cu-H₂O nanofluids are Newtonian fluids.

Abstract: To deal with the complicated spiral surface of screw pump,this article uses Pro/E to build geometry model.And it improves the method of the grid topology to use the dynamic grid ideas.At the same time,using the method of Computational Fluid Dynamics to numerical simulation for full-metal single screw pump,analysis and study that viscosity affect leakage properties,the torque of surface of rotor and the volumetric efficiency.

Abstract: Modern models of soils to describe elastic-viscoplastic properties do not always lead to the desired results , especially when it is necessary to take into account the time factor. In particular, one cannot always describe the rheological model and creep and relaxation , as well as get extreme at kinematic mode loading. This is due to the fact that the deformation in the soil medium is accompanied by complex physical and physico-chemical phenomena , changes in the orientation of each mineral particles in space and time , their mutual offset seal ( hardening ) and decompression ( softening ) . Quantitative assessment of buildings and facilities associated with the calculation of the stress - strain state ( SSS ) foundation soils subject to numerous factors , including the physical feature of the power and influence ( statics, kinematics, dynamics ) and mechanical properties of soils under such effects ( creep , ductility ) .In the present paper the results of scientific studies of the rheological properties of sandy soils. The purpose of these studies - determination of viscosity sandy soils kinematic and dynamic triaxial test mode. A technique for determining the viscosity of soils results in triaxial kinematic mode (with speed control vertical movements). The paper considers the problem of estimating the impact of the dynamic loads on the viscosity of sandy soils.

Abstract: Viscosity, as one of important performance indexes of liquid-phase heat transfer fluids, its measurement methods and instruments have developed greatly in recent years. This paper introduces the traditional methods and theory of measuring liquid-phase heat transfer fluids’ viscosity as well as summarizes the development of measuring liquid-phase heat transfer fluids viscometer at home and abroad.

Abstract: Temperature dependences of liquid alloys contain non-monotonic fragments in the form of excesses and breaks. The paper analyzes the dependences of oscillations’ attenuation ratio upon temperature. The qualitative and quantitative estimation of anomalies on melt properties’ dependences upon temperature is made, for example, values of viscosity. The proposed approach allows analyzing properties of the melt and developing technological recommendations for production of materials possessing high characteristics.