Abstract: Sulfur-containing compounds of the formula ##STR1## WHEREIN R is a hydrocarbyl radical; each of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is independently hydrogen or a hydrocarbyl radical; m' is from one to about five; and each A is an alkyl radical containing at least one carboxyl group or functional derivative thereof, are useful as additives in lubricants and fuels.

Abstract: A method and apparatus are disclosed for mixing two previously separated fluids at a downhole location adjacent a predetermined formation interval.

Abstract: A method for transporting gravel to a production zone with a circulating well fluid to uniformly pack the gravel in the annular space in the wall between the perforated liner and the formation whereby the fluid enters the perforated liner after depositing gravel at the top of the annular column of gravel and flows through the liner inner annulus into a tailpipe through which the well fluid is returned to the surface.The well fluid carrier for the gravel is prevented from entering the perforated or slotted liner except at the top of the gravel sheath by a semi-solid material pre-positioned in the slotted liner-tailpipe annulus. The semi-solid material is progressively eroded by the well fluid entering the slotted liner-tailpipe annulus at the top of the gravel sheath.