Abstract: A method for prolonging a hydroconversion catalyst life-time is provided. An additive functional to partially redirect the deposition of catalytic poisoning agents on the catalyst is utilized. The additive may comprise a chemically inert, porous carbonaceous material or ferruginous clay.

Abstract: Apparatus for monitoring the cloud point of a liquid, or the temperature at which any light scattering phase occurs therein, comprising a light-proof and light-absorbing chamber, and a liquid sample-receiving receptacle within the chamber having a bottom formed by a non-light-scattering surface; this surface being in thermal contact with a heating or cooling device, such as a thermoelectric cooler, and with a temperature measurement device. The chamber can be opened to allow access to the receptacle so that sample liquid can be placed therein. A light beam source is located to direct a beam of light onto the surface at an incident angle so that light from the beam is reflected or absorbed by the surface. A light detector including a lens and an array of detection cells is arranged so as to detect scattered light which is produced when solid material forms in the liquid as it is cooled or disappears on heating.

Abstract: A switch for an inductive load includes a first leg having a first field effect transistor connected between one terminal of the load to the high potential terminal of a power supply and a second leg having a second field effect transistor connected between the other terminal of the load and the low potential terminal of the power supply. A plurality of current paths located on opposite sides of the load terminals connected in parallel and extend from one of the load terminals to one of the power supply terminals. Each current path includes an inductor connected in series with a diode. A choke energy path is associated with each current path and includes a diode connected in series with a resistors. The inductors in the current paths operate to inhibit reverse recovery current through the diodes while the choke energy paths dissipate oscillation energy in the switch upon operation of the transistors to connect the inductive load across the terminals of the power supply.

Abstract: The dew points of condensible hydrocarbon and water in a gas stream are determined independently in a single run by observing changes in intensity of light scattered from a mirror surface which is cooled to below both of the dew points. A decrease in intensity denotes the hydrocarbon dew point while an increase in intensity denotes the water dew point. The apparatus is simple and operates automatically. The mirror surface has a first polished and highly reflective portion and a second, roughened, less reflective portion. The intensity of scattered light is preferably monitored separately for each mirror portion.

Abstract: A novel asphaltic composition consisting of from about 2% to about 10% w/w of a hydrocracking residue which is the distillation residue obtained from a hydrocracking process of heavy crude oil in admixture with from about 98% to about 90% w/w of a conventional asphalt. These asphaltic compositions are especially useful when mixed with mineral aggregate to provide road mixes which lead to improved road construction or road paving.

Abstract: Flow-induced pressure pulsations in a piping system transporting natural gas or other gaseous medium are suppressed by disturbing the shear layer in the open end of a sidebranch line. Inserts are located in the sidebranch line to effect the shear layer disturbance.

Abstract: A method of controlling and selectively reducing the permeability of zones in an oil-bearing underground formation which have higher permeabilities than the surrounding zones by injection of exopolymer producing microorganisms into the oil-bearing formation is described. The exopolymer production of the microorganisms used in the method is controlled by regulation of the availability to the microorganisms of a compound such as sucrose which triggers exopolymer production.

Abstract: A method of controlling and selectively reducing the permeability of zones in an oil-bearing underground formation which have higher permeabilities than the surrounding zones by injection of exopolymer producing microorganisms into the oil-bearing formation is described. The exopolymer production of the microorganisms used in the method is controlled by regulation of the availability to the microorganisms of a compound such as sucrose which triggers exopolymer production.