Abstract: A hand-held apparatus for spraying foam comprises (a) a manually-operated dispensing pump capable of receiving a foamable liquid from a suitable container and ejecting it into the atmosphere through an atomizing nozzle, thereby forming a spray from such liquid and projecting it outwardly from the nozzle in a predetermined spray pattern, and (b) foam-forming device including an air inlet and a screen retained in the path of the spray. The screen can be retained in a foam-forming position by suitable means such as a housing operatively associated with the dispensing pump. Substantially all the spray passes through the foam-forming device without contact except by the screen, thereby generating foam with little modification of the predetermined spray pattern.

Abstract: An improved method for the continuous removal of dissolved oxygen from a flowing liquid containing sample bands, the invention being effective to remove the interference of the dissolved oxygen for purposes of reductive electrochemical detection of analyte of interest. As an example of utility, using a silicone rubber membrane in a shell and tube design, typically >99 percent of the dissolved oxygen can be removed by permeation from aqueous solutions within a residence time of six seconds. Applications of the technique to the post-column removal of dissolved oxygen from ion exchange and reverse phase chromatographic mobile phases prior to reductive electrochemical detection are particularly described and claimed.

Abstract: Apparatus for accurately metering liquid flow based on the injection of a brief heat pulse into the flowing stream, e.g., via a miniature thermistor, and detection of an electronic time derivative of temperature downstream with, e.g., a second microprobe thermistor. This detection triggers a subsequent heat pulse and the cycle repeats, wth pulse total corresponding to elapsed liquid throughput, and pulse frequency to flow rate.

Abstract: Method and apparatus for the batch preparation of sample aliquots by solvent extraction and separation of soluble species from sample comprising nonsoluble particulate, which comprises a receptacle which defines a sample receiving space into which a measured amount of sample is placed, a fluid-permeable filter which is remote from and communicates with the sample receiving space, means to add a metered quantity of solvent to the sample receiving space, means to supply pressurized gas to the sample receiving space to slurry the solvent with the sample, means to invert the receptacle to position the slurry into filtering contact with the filter, and means to collect a sample aliquot comprising the filtered liquid phase of the slurry.

Abstract: The molecular weight and molecular weight distribution of diverse ultra-high molecular weight water soluble polymers is rapidly determined based on apparent size by passage of extremely dilute samples of the polymer (1-250 ppm) through a column of nonporous packing whereby separation into molecular weight (apparent size) fractions is obtained predominantly based on flow (i.e., hydrodynamic chromatography). Detection of the extremely dilute sample polymer is accomplished, e.g., by tagging the polymer with a fluorescent agent and using a flow-through fluorometer detector. The molecular weight characterization of the polymers is determined independent or less dependent of the composition of the polymer by analyzing the sample in its nonionized form.

Abstract: An improved apparatus and method are disclosed for measuring the dynamic surface tension at a gas-liquid interface by the maximum bubble pressure method. The gas is bubbled out an orifice tube dipped in the liquid; the maximum pressure in each bubble is a function of the surface tension. In the invention, the rate of gas flow is raised continually to increase the rate of bubbling at least several fold over a few minutes. The varying pressure of the bubbling gas is measured continuously by an instantaneous transducer. Electronic circuits respond to the transducer and provide signals indicative of the maximum bubble pressure and of the rates of bubbling. A recorder responds to the signals and displays a spectrum of the maximum bubble pressure in units indicative of surface tension as a function of the bubbling rate. Measurements may be taken over more than a thousand bubbles in each spectrum.

Abstract: An improved chromatographic analytical column, the column containing a pellicular type (agglomerated) anion-exchange packing, comprising:Component A, which comprises a pressure packed bed of substrate particles of insoluble synthetic resin, having cation-exchanging sites at least on their available surfaces, the Component A particles being of low porosity relative to Component B microparticles, described below, andComponent B, derived by agglomerating microparticles of insoluble synthetic resin onto the pressure packed bed of Component A particles, the microparticles having a volume average diameter of less than about 1,500 and greater than about 50 Angstroms and having anion-exchanging sites, at least on their outer surfaces, which attract available cation sites of Component A, wherein the microparticles of Component B are attached as a monolayer to the available surfaces of the Component A particles.

Abstract: Method for electronically metering the flow of Newtonian liquids which comprises:(a) conveying the liquid to be metered through an electronic flow cell having a predetermined calibrated cell volume (V.sub.c) and calibrated time constant (K);(b) inputting uniformly timed heat pulses into the conveyed liquid and detecting the pulses downstream and wherein each detection event triggers the input of a timed heat pulse to produce the condition of pulse frequency being related to liquid flow rate (f);(c) electronically detecting the period (T) between pulses; and(d) determining a measure of flow of the metered liquid based on the application of the relationship, T=V.sub.c /f+K.

Abstract: A permselective ion-exchange membrane, preferably comprising hollow fiber(s) immersed within a regenerant, is used to selectively neutralize or suppress the conductivity of electrolyte in a stream of eluent also containing chromatographically separated ions. The invention particularly specifies a chromatographic separating column useful with an electrolyte eluent solution to separate ionic species by elution chromatography, wherein the effluent of the separator column is treated by the described membrane to suppress the conductivity of the electrolyte but not that of the separated ions.

Abstract: A hand-held apparatus for spraying foam comprises (a) a manually-operated dispensing pump capable of receiving a foamable liquid from a suitable container and ejecting it into the atmosphere through an atomizing nozzle, thereby forming a spray from such liquid and projecting it outwardly from the nozzle in a predetermined spray pattern, and (b) foam-forming device including an air inlet and a screen retained in the path of the spray. The screen can be retained in a foam-forming position by suitable means such as a housing operatively associated with the dispensing pump. Substantially all the spray passes through the foam-forming device without contact except by the screen, thereby generating foam with little modification of the predetermined spray pattern.

Abstract: An improved process for etching (eroding) the inner surface of a glass capillary column in which ammonium bifluoride in liquid methanol is passed slowly through the capillary bore for a prolonged period, followed by rinsing with methanol, thereafter a gradually diluting rinse mixture of methanol and water, and finally a pure water rinse. A very fine structured etch of uniform depth is produced with no apparent air entrainment making the columns suitable for all standard stationary phase coating procedures.

Abstract: Reagent is added to liquid chromatographic effluent to increase detection sensitivity of sample bands, or to enhance sensitivity with respect to interfering bands which overlap sample bands of interest, using one or more hollow fibers immersed within mobile reagent which is permeated through the walls of the fibers and, thus, ultimately diffused into the column effluent.

Abstract: Reagent is added to liquid chromatographic effluent to increase detection sensitivity of sample bands, or to enhance sensitivity with respect to interfering bands which overlap sample bands of interest, using one or more hollow fibers immersed within mobile reagent which is permeated through the walls of the fibers and, thus, ultimately diffused into the column effluent.

Abstract: Liquids are monitored for dissolved halogens using amperometric detection based on the use of halogen specific electrodes of a conductive substrate on which is formed an adherent surface film of [Ti.sub.x (Ru, Ir).sub.1-x ]O.sub.2, wherein x=mole fraction .gtoreq.0 to <1, and (Ru, Ir) represents either ruthenium or iridium or mixtures thereof. The described electrodes resist corrosion and failure in extremely harsh environments, e.g., hot concentrated brine solutions.

Abstract: An improved 3-pole membrane electrode for polarographic measurements in which an auxiliary electrode is defined having an arc which is generated by rotation about the center point of a disc-shaped working electrode. A preferable liquid junction form of reference electrode is located in the sector defined by the arc of the auxiliary electrode and the center point of the working electrode; and an analyte permeable membrane is intimately conformed over the sensing face of the improved polarographic electrode.

Abstract: An improved technique for the measurement of ions in solution where the ions of interest are chromatographically displaced from an ion exchange column by an eluting ion which is or is made light-absorbing, and where the eluted sample ions, which are transparent (at the monitored wavelength), are detected and quantified from the decrements they cause in effluent absorbance as revealed by photometric monitoring.

Abstract: A reversible liquid/solid phase change composition comprising hydrated MgCl.sub.2 and one or more of Ba(OH).sub.2, Sr(OH).sub.2, CaO, SrCO.sub.3, BaO, Ca(OH).sub.2, Mg(OH).sub.2, MgO, Na.sub.3 AlF.sub.6 or CaC.sub.2 O.sub.4, added to the composition in an effective amount to suppress supercooling of the MgCl.sub.2 liquid phase.

Abstract: A reversible liquid/solid phase change composition comprising hydrated Mg(NO.sub.3).sub.2 /MgCl.sub.2, and one or more of Sr(OH).sub.2, Ca(OH).sub.2, CaO or BaO, added to the composition in an effective amount to suppress supercooling of the Mg(NO.sub.3).sub.2 /MgCl.sub.2 liquid phase.

Abstract: An improved pellicular type (agglomerated) anion-exchange chromatographic packing composition which comprises:Component A, a substrate which consists essentially of particles of insoluble synthetic resin, having cation-exchanging sites at least on their available surfaces, the Component A particles being of a diameter of between about 5 to 75 microns and of low porosity relative to Component B microparticles, described below, andComponent B, which consists essentially of microparticles of insoluble synthetic resin, having a volume average diameter of less than about 900 and greater than about 50 Angstroms, the microparticles having anion-exchanging sites, at least on their outer surfaces, which attract available cation sites of Component A, wherein the microparticles of Component B are attached as a monolayer to the available surfaces of the Component A particles.