Showing papers in "Analytica Chimica Acta in 1985"

TL;DR: In this article, a simple relationship was derived which expressed the change in oscillation frequency of a quartz crystal in contact with a fluid in terms of material parameters of the fluid and the quartz.

TL;DR: In this article, the influence of salts containing lipophilic cations and anions on the electrical resistance of the membranes of macro-and micro-electrodes based on a neutral carrier is described.

TL;DR: In this article, the same restrictions with regard to overlap and relative signal heights of the compounds seem to apply to the conventional method of curve resolution and the proposed method is tested on data from high-performance liquid chromatography with a diode-array detector obtained for polynuclear aromatic hydrocarbons and for proteins.

TL;DR: In this article, a chemically modified electrode for detection of dihydronicotinamide adenine dinucleotide (NADH) and dihydronamide adnine din nucleotide phosphate was described, where graphite rods were modified by dipping them into solutions ofdimethylamino-1,2-benzophenoxzinium salt.

TL;DR: In this article, a review of micelles and their applications in many types of analytical methods is presented. But the focus of the review is not on the performance of the mouselles, but on the micro-emulsions in shifting acid-base equilibria.

TL;DR: In this article, an extension of the multivariate curve resolution theory is presented based on the minimum assumptions of non-negativity of sensor responses and non-negative of quantities of components, as given by Lawton and Sylvestre.

TL;DR: The glucose oxidase column showed little change in activity over a 10-month period and compared well with those obtained by a conventional analyser system.

TL;DR: The spectrum of cobalt chloride on the fiber is similar to a transmission spectrum rather than an attenuated totla reflection (a.t.r.) spectrum because of the refractive index of the film which is slightly greater than that of the fiber.

TL;DR: In this article, glassy carbon electrodes subjected to severe electrochemical treatment is saturated chloride solutions exhibit enhanced electrochemical reversibility compared to untreated electrodes, and the most significant improvement is observed in differential pulse measurements, that are highly sensitive to small changes in the rate of electron transfer.

TL;DR: The effect of pH on the fluorescence of the most prominent components and on the pattern of the map is described, and measurement of total fluorescence spectra is considered to be a potentially useful basis for application of pattern recognition.

TL;DR: In this article, a survey of applications and performances of Fourier transform mass spectrometers is presented, including ultra-high-resolution electron-impact and chemical ionization mass spectra, gas chromatography/F.m.t.s. performance, pulsed Cs + -s.i.

TL;DR: In this paper, a modified carbon electrode for the amperometric determination of hydrogen peroxide is described, by deposition of a 15nm thick layer of a 40:60 mixture of palladium and gold on the surface of the electrode, the overvoltages for both the oxidation and reduction can be decreased by at least 800 mV.

TL;DR: Based on amplification by the recyclization reactions catalyzed by these two-enzyme systems, NADH, NAD+, glucose, lactate and pyruvate are determined with 8–40-fold increased sensitivity compared to the unamplified reactions.

TL;DR: In this article, a procedure based on total-reflection x-ray fluorescence spectrometry (t.x.r.f) was used to determine dissolved heavy metal traces in sea water.

TL;DR: In this article, a spectrophotometric measurement of the copper(I) complex of bathocuproine (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) is described.

TL;DR: In this article, a mixed dithiocarbamate/Freon TF extraction system is used to separate trace metals from major constituents, prior to back extraction into a final dilute nitric acid solution and subsequent determination of the metals by graphite-furnace atomic absorption spectrometry.

TL;DR: In this paper, an enzyme electrode with a chemically-amplified response for l -lactate is constructed from an oxygen electrode and a layer containing immobilized lactate oxidase, to oxidize l - lactate, and lactate dehydrogenase to regenerate the l − lactic acid.

TL;DR: In this paper, an optical sensor is prepared by immobilizing quinolin-8-ol-5-sulfonate (QS) on an ion exchange resin and attaching the resin to the end of a trifurcated fiber-optic bundle.

TL;DR: Reflectance spectrophotometry is applied to flow-injection measurements of pH and assays of ammonia and urea with the aim of demonstrating the principle and testing the performance of optosensors integrated into microconduits as mentioned in this paper.

TL;DR: In this paper, an electron mediator between glucose oxidase and a reticulated vitreous carbon (RVC)/graphite support bed was constructed by immobilization of glucose and ferrocene into cross-linked polyacrylamide gels.

TL;DR: In this paper, a vapour-injection method is described for the calibration of mercury determinations, which depends mainly on the temperature of the mercury-saturated air, which must be lower than the ambient temperature.

TL;DR: The behavior of 19 fluorescent compounds of various types in peroxyoxalate chemiluminescence reactions was studied in terms of the relation of their excitation efficiency to their singlet excitation energy and oxidation potential as mentioned in this paper.

TL;DR: In this article, a very sensitive electrochemical stripping procedure for aluminum was reported, which achieved the accumulation by controlled adsorption of the aluminum/solochrome violet RS complex on the static mercury drop electrode.

TL;DR: In this article, the reaction of glycine with NBD-F (4fluoro-7nitrobenzo-2-oxa-1,3-diazole) is investigated to establish conditions that provide a high formation rate of NBDglycine and a low hydrolysis rate of the reagent.

TL;DR: In this article, a solid-state reactor for detection of hydrogen peroxide in aqueous samples by peroxyoxalate chemiluminescence is described, where Bis(2,4,6-trichlorophenyl)oxalates are packed into a bed reactor, which eliminates mixing problems and facilitates the instrumental development.

TL;DR: In this article, a thin-layer cell with a glassy carbon working electrode and an inlet valve is used to suck six different solutions through a peristaltic pump.

TL;DR: In this article, the acid-base properties of aquatic fulvic acid, concentrated from the Gota River, were studied by means of potentiometri titrations, and it was found that the three most acidic groups were carboxylic.

TL;DR: The frequency of oscillation of a piezoelectric quartz crystal immersed in solution changes with the temperature of the solution and with the ambient temperature of an oscillator, especially where the latter is transistorized as discussed by the authors.

TL;DR: The analytical uses of carbon fibre electrodes cover such diverse areas as coulometry, potentiometry, anodic stripping voltammetry, potentio-electrochemistry and kinetic measurements as mentioned in this paper.