Abstract: Method and apparatus are provided for sealing an open end of a sheathed cable. After removing a length of insulating jacket, the open end of the cable is placed in a pressure block and a viscous sealant material is injected into the block and into the open end of the cable. After injection, the cable is removed from the block and the sealant allowed to cure to a gel-like consistency. Fluid which may invade the interior of the cable above the seal is, therefore, prevented from passing by the seal and entering a transducer or other instrument secured to the end of the cable. In the preferred embodiment, a cable head, O-ring and transducer body are also provided to enclose the transducer in a substantially waterproof housing.

Abstract: A process for eluting gold-iodine complex from an ion-exchange resin, characterized by adding sulfuric acid and sodium nitrite to the gold-iodine complex adsorbed on the resin, and adding sodium sulfite as an eluant. The process is particularly useful for eluting gold-iodine complex adsorbed on strongly basic anion-exchange resin, such as washings resulting from the washing of leach residue which has been passed through the resin.

Abstract: Apparatus and method are provided to ensure accuracy of a measurement signal obtained using a potentiometric sensor placed in a solution. The apparatus includes an interface amplifier that generates a relatively large turn-on bias current whenever the amplifier is initially powered on. To avoid polarization of the potentiometric sensor by the turn-on bias current, a switch device is used to direct the turn-on bias current along a path away from the potentiometric sensor. The switch device is controlled using a timer circuit that causes a change in position of the switch device after a predetermined time delay. During the time delay, the bias current reduces to a normal value and polarization of the potentiometric sensor has been avoided. An accurate measurement of a physical parameter associated with the solution can then be taken without the detrimental effect of the turn-on bias current on the potentiometric sensor.

Abstract: An accurate analog measurement system is provided for reducing the effects, characterized by variations in gain and offset, that analog signals experience when transmitted from one point to another. The accurate analog measurement includes at least one transducer having a reference signal, scaling signal and output signal. The reference signal provides the baseline relative to which the scaling and output signals are measured. Indicative of the phenomena being measured by the transducer is the output signal. The scaling signal, preferably, represents the maximum possible output signal. The present invention also includes means for forcing the reference, scaling and output signals onto a common path so that each signal experiences the same variations when transmitted to a processing station of the present invention.

Abstract: An apparatus and method are provided for reducing the effects that common mode currents and/or voltages have on the measurements made by instrumentation that senses physical phenomena. The apparatus includes a cell having a first sensor, a second sensor and a passageway for containing the fluid to be measured. The cell, sensors and passageway are symmetrically disposed about an axis. Due to this symmetry, a ground can be located at the axis of symmetry. The apparatus also includes first and second measuring circuits associated, respectively, with the first and second sensors. The first measuring circuit produces a signal respresentative of the measured parameter between the ground and the first sensor. The second measuring circuit provides a like function for the second sensor. The signals produced by the first and second measuring circuits are summed by a potentiometer.

Abstract: An improved process for recovering gold from gold-containing materials by iodide/iodine leaching is provided wherein the pregnant lixiviant containing solubilized gold and iodine is treated in an electrolytic cell to reduce gold in solution to elemental gold for recovery and reduce iodine to iodide at the cathode, so as to prevent iodine from interfering with subsequent gold recovery processes, and at the same time reoxidize iodide present at the anode to elemental iodine to regenerate the leach solution to the desired iodide:iodine weight ratio, e.g. about 2:1 to about 10:1. Gold is precipitated in the cathode compartment, and if desired, the cathode effluent may be treated for further removal of traces of gold before being passed to the anode compartment. A method for preventing iron contamination of the cathode is also provided comprising buffering the lixiviant solution to a pH of about 5.

Abstract: Apparatus and method are provided for sensing the presence of product and/or water in the annular space of a double wall storage tank. The apparatus includes both a product sensing element and a water sensing element that are operatively associated with each other to control the compression of a spring. The spring is operatively connected to a colored marker which is able to move from within an opaque tube to within a transparent tube using the force of the spring. When the product sensing element is contacted by product or the water sensing element is contacted by water so that the respective sensor weakens, the spring force is used to move the colored marker so that it is within the transparent tube. In such a position, the colored marker becomes visible, indicating that product and/or water are present in the annular space of the double wall storage tank.

Abstract: An apparatus and method are provided for detecting solvents, including hydrocarbons. The apparatus includes a hydrocarbon-soluble plastic rod which interconnects a mass or weight and a weighing assembly. The weighing assembly is operatively joined to an alarm indicator, which is utilized to inform the user as to whether hydrocarbons are present. In a preferred arrangement, the weighing assembly is connected to a housing, which is joined to the top of a well casing provided in the ground. The plastic rod may be of any desired length, depending upon the depth of the well casing and where it is desired to check for hydrocarbons. When hydrocarbons are detected the plastic rod dissolves or separates causing movement of the weighing assembly and the alarm indicator so that a visual indication is provided that hydrocarbons are present. The apparatus further includes a mass catch assembly for maintaining connection between the mass and the housing after the plastic rod separates due to the presence of hydrocarbons.

Abstract: A process for the hydrometallurgical recovery of gold from materials containing gold comprising leaching the materials with a lixiviant containing iodine. To a solution concentrated with natural salts is added elemental iodine until saturated, whereupon mineral sulfides in the ore zone charged with this solution react with the iodine to form iodide. Additional elemental iodine is then added to this iodide-bearing solution until the desired concentration of total iodine and ratio of iodine to iodide are achieved for optimum leaching. The lixiviant is then circulated through the ore zone until all the gold is dissolved. Gold is subsequently recovered on activated charcoal. The excess iodide formed during the process is reoxidized to iodine electrochemically in a special diaphragm cell to regenerate the lixiviant.

Abstract: New solvent compositions and a new two-stage direct coal liquefaction process are provided which permit control of the liquid product state from one consisting primarily of low boiling distillate to one consisting primarily of high boiling fuel oil. The use of the new solvent composition in the process significantly increases distillable liquid yields from coal or lignites. The preferred solvent contains from about 0 to 100 weight percent of pyridine-soluble bottoms, i.e., mineral matter-free normally solid dissolved coal, in which the hydrogen content is maintained at an optimum level by adding from about 0.05 to about 2.0 weight percent hydrogen in a hydrotreating step and from about 0 to 100 weight percent of a coal-derived distillate boiling below about 800.degree. F. to about 1000.degree. F.