A new rotation-viscometer with a submerged, magnetically balanced rotor

1982 ◽  
Vol 311 (4) ◽  
pp. 362-362 ◽  
Author(s):  
R. Brust ◽  
V. Muth
Keyword(s):  
Rotation Viscometer

scholarly journals DILATANCY OF CEMENT SLURRIES WITH CHEMICAL ADMIXTURES

2004 ◽  
Vol 10 (3) ◽  
pp. 227-233 ◽  
Author(s):  
Gintautas Skripkiūnas ◽  
Mindaugas Daukšys
Keyword(s):  
Experimental Investigation ◽  
Chemical Composition ◽  
Rheological Properties ◽  
Disperse Medium ◽  
Coaxial Cylinder ◽  
Structural System ◽  
Chemical Admixtures ◽  
Rotation Viscometer

The results of experimental investigation of plasticising, air‐entraining and viscosity‐modifying admixtures with different chemical composition influence on rheological properties and dilatancy of cement slurries are presented in the article. Rheological properties of cement slurries were tested by a rotation viscometer with coaxial cylinder, at different gradients of velocity. Dilatancy of cement slurries was determined by the distortion of the rheological curve and index of dilatancy D was calculated according to proposed methods. The results of investigation show that the properties of liquid disperse medium of structural system influence slightly the dilatancy of cement slurries. Plasticising admixtures with a different chemical composition slightly increases but air-entraining and viscosity-modifying admixtures slightly reduces the dilatancy of cement slurries.

The Effect of Fluorine on the Viscosity and Crystallization of Lithium Aluminosilicate Glasses

2012 ◽  
Vol 509 ◽  
pp. 346-352
Author(s):  
Wei Hong Zheng ◽  
Yang Dai ◽  
Mo Zhou Lin ◽  
Kun Yang ◽  
Hao Wu
Keyword(s):  
Melting Temperature ◽  
Glass Ceramics ◽  
Fluorine Content ◽  
X Ray Diffraction ◽  
Lithium Aluminosilicate ◽  
X Ray ◽  
Melting Temperatures ◽  
Aluminosilicate Glasses ◽  
Main Crystalline Phase ◽  
Rotation Viscometer

Lithium aluminosilicate glasses have high viscosities, resulting in high melting temperatures and processing temperatures. In this study, F was added to the LAS glasses to reduce the melting temperature and viscosity for float process. The effects of fluorine content on the viscosity and crystallization of the parent glasses were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA) and rotation viscometer. It was found that the addition of F was useful in reducing the melting temperature and viscosity. The main crystalline phase of resulting glass-ceramics was β-spodumene. The activation energy (E) of LAS glasses was decreased from 460.3 KJ/mol to 417.7 KJ/mol with the addition of 2.63 wt% F, which accelerated the crystallization and enhanced the crystallinity of specimens.

Temperature Effects in Rotation Viscometer

1953 ◽  
Vol 25 (9) ◽  
pp. 1390-1393 ◽  
Author(s):  
C. C. Mill ◽  
E. R. Gates
Keyword(s):  
Temperature Effects ◽  
Rotation Viscometer

INFLUENCE OF CEMENT TYPE AND ADMIXTURES ON RHEOLOGICAL PROPERTIES OF CEMENT PASTE / CHEMINIŲ ĮMAIŠŲ POVEIKIS REOLOGINĖMS CEMENTO TEŠLOS SAVYBĖMS

2014 ◽  
Vol 5 (4) ◽  
pp. 175-181 ◽  
Author(s):  
Mindaugas Macijauskas ◽  
Albinas Gailius
Keyword(s):  
Portland Cement ◽  
Induction Period ◽  
Rheological Properties ◽  
Cement Paste ◽  
Flow Characteristics ◽  
Cement Pastes ◽  
Chemical Admixtures ◽  
Materials Used ◽  
Rotation Viscometer ◽  
Portland Cement Paste

The article aims to research the influence of the chemical admixtures on the rheological properties of Portland cement paste and determine their impact on the effectiveness of hydration induction period. Materials used in the study: Portland cement CEM I 42.5 (N and R early strength), limestone Portland cement CEM II/A-LL 42.5 N, plasticizer Centrament N3, the latest generation superplasticizer MC-PowerFlow 3140 and water. Investigations focused on effects of Plasticizer and superplasticizer on water and cement (W/C) ratio and Portland cement paste flow characteristics. Portland cement pastes with the same watercement ratio with and without chemical admixtures were tested. Investigations were carried out using a Suttard viscometer and rotation viscometer Rheotest NH 4.1 with coaxial cylinders. It was observed that viscosity of Portland cement paste can be controlled by chemical admixtures during the hydration induction period. Investigations of effectiveness of the chemical admixtures on the rheological properties of the Portland cement pastes, comparing it with a control composition of the Portland cement paste were provided in the article. Diagrams show changes of the viscosity of the Portland cement pastes depending on the type and amount of the used chemical admixtures. Obtained results were compared with the same consistence without admixtures. After making the regressive analysis of research results of Portland cement paste with and without chemical admixtures, empirical equations were produced. Santrauka Šio darbo tikslas – ištirti cheminių įmaišų poveikį reologinėms portlandcemenčio tešlų savybėms ir nustatyti jų poveikio veiksmingumą indukcinio hidratacijos periodo metu. Tyrimams naudotos šios medžiagos: AB „Akmenės cementas“ gamyklos portlandcementis CEM I 42,5 (N ir R ankstyvojo stiprumo), klinties portlandcementis CEM II/A-LL 42,5 N, plastiklis Centrament N3, naujausios kartos superplastiklis MC-PowerFlow 3140 ir vanduo. Ištirtas plastiklio ir superplastiklio poveikis vandens ir cemento (V/C) santykio pokyčiams ir portlandcemenčio tešlų sklidumui naudojant Sutardo viskozimetrą. Buvo tiriamos vienodo vandens ir cemento santykio portlandcemenčio tešlos su cheminėmis įmaišomis ir be jų. Tyrimai atlikti naudojant rotacinį viskozimetrą Rheotest NH 4.1 su bendraašiais cilindrais. Nustatytas cheminių įmaišų portlandcemenčio tešlose veiksmingumas. Pastebėta, kad portlandcemenčio tešlų dinaminė klampa gali būti reguliuojama cheminėmis įmaišomis viso indukcinio hidratacijos periodo metu. Atlikus portlandcemenčio tešlų su cheminėmis įmaišomis ir be jų tyrimų rezultatų regresinę analizę, gautos empirinės lygtys.

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