This disclosure is directed to an improved ballistic concrete barrier for stopping projectiles with a kinetic energy of between about 1.0 kJ (750 foot-pounds) and 20.3 kJ (15,000 foot-pounds) in between about 3 inches and 10 inches.

This disclosure is directed to an improved ballistic concrete barrier for stopping projectiles with a kinetic energy of between about 1.0 kJ (750 foot-pounds) and 20.3 kJ (15,000 foot-pounds) in between about 3 inches and 10 inches.

At least one glycol compound is used as a grinding aid when grinding at least one solid substance, in particular an inorganic and/or mineral solid substance, in a rolling mill, wherein the at least one glycol compound has a structure according to formula I: (formula 1) and wherein a) R1, R2, R3 each independently of one another stand for H or an alkyl, alkoxy or alkanol group with 1-8 carbon atoms, in particular with 2-4 carbon atoms; and b) X stands for a substituted or unsubstituted alkylene group with 1-8 carbon atoms, in particular 1-4 carbon atoms.

At least one glycol compound is used as a grinding aid when grinding at least one solid substance, in particular an inorganic and/or mineral solid substance, in a rolling mill, wherein the at least one glycol compound has a structure according to formula I: (formula 1) and wherein a) R1, R2, R3 each independently of one another stand for H or an alkyl, alkoxy or alkanol group with 1-8 carbon atoms, in particular with 2-4 carbon atoms; and b) X stands for a substituted or unsubstituted alkylene group with 1-8 carbon atoms, in particular 1-4 carbon atoms.

Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

A method of treating a lost circulation zone in a wellbore includes contacting an accelerant composition comprising triethanolamine with a cement composition in the lost circulation zone, the cement composition comprising at least: from 1 weight percent (wt. %) to 90 wt. % cement precursor based on the total weight of the cement composition; and from 5 wt. % to 70 wt. % water based on the total weight of the cement composition; where a weight ratio of triethanolamine to the cement precursor is from 0.1 percent (%) to 60%; and curing the cement composition in the lost circulation zone to form a cured cement, where the triethanolamine accelerates the curing rate of the cement composition and the cured cement seals the lost circulation zone.

A method of treating a lost circulation zone in a wellbore includes contacting an accelerant composition comprising triethanolamine with a cement composition in the lost circulation zone, the cement composition comprising at least: from 1 weight percent (wt. %) to 90 wt. % cement precursor based on the total weight of the cement composition; and from 5 wt. % to 70 wt. % water based on the total weight of the cement composition; where a weight ratio of triethanolamine to the cement precursor is from 0.1 percent (%) to 60%; and curing the cement composition in the lost circulation zone to form a cured cement, where the triethanolamine accelerates the curing rate of the cement composition and the cured cement seals the lost circulation zone.

A chemical additive for calcium sulphoaluminate-modified Portland cement comprises the following substances: (a) at least one alkanolamine borate; (b) at least one organic alcohol; and (c) at least one saccharide or a derivative thereof; and the substances and water are sequentially mixed and stirred to obtain the chemical additive for calcium sulphoaluminate-modified Portland cement. The chemical additive for calcium sulphoaluminate-modified Portland cement provided by the invention has better effects of regulating the setting time of the calcium sulphoaluminate-modified Portland cement and improving the 3d/28d strength increase rate, and also has a grinding aid effect when being added during grinding.

A chemical additive for calcium sulphoaluminate-modified Portland cement comprises the following substances: (a) at least one alkanolamine borate; (b) at least one organic alcohol; and (c) at least one saccharide or a derivative thereof; and the substances and water are sequentially mixed and stirred to obtain the chemical additive for calcium sulphoaluminate-modified Portland cement. The chemical additive for calcium sulphoaluminate-modified Portland cement provided by the invention has better effects of regulating the setting time of the calcium sulphoaluminate-modified Portland cement and improving the 3d/28d strength increase rate, and also has a grinding aid effect when being added during grinding.