Commercialization of three processes (OPPA, DBPA-TOPO and OPAP) has shown that the DEPA-TOPO process offers the best technology available today for the recovery of uranium from wet-process phosphoric acid. Uranium recovery plants using this process have been successfully operated in the United States, Belgium, Canada and Taiwan. Operating experience from these plants has led to a significant re...

The flaky graphites were prepared from lignite. The effects of phosphoric acid ratios and pyrolysis temperatures on flake formation were studied by SEM, TEM and XRD. The results showed that the flaky graphite occurred at a pyrolysis temperature of 600°C with a 1.0:1.0 ratio of carbon to phosphoric acid. The flaky formation was almost completed by pyrolysis at 800°C and with a 1:2.0 ratio of car...

statement of problem: in some clinical situations, repair of composite restorations is treatment of choice. improving the bond strength between one new and old composite usually requires increased surface roughness to promote mechanical interlocking since chemical bonding might not be adequate. similarly, the treatment of a laboratory fabricated resin composite restoration involves the same pro...

For the determination of adenosine-5’-phosphoric acid and its homologues the methods which have been recommended chiefly are (1) enzymatic deamination by deaminase and quantitative determination of the ammonia split off (1) ; (2) determination on the basis of the pharmacological activity, (a) contraction of the isolated guinea pig uterus, (b) the characteristic change in the electrocardiogram u...

1. Mycelium of Rhizopus nigricans when stained with certain acid and basic dyes and washed with buffer mixtures of 0.1 M phosphoric acid and sodium hydroxide responded much like an amphoteric colloid with an isoelectric point near pH 5.0. 2. When grown on potato dextrose agar the reaction of which was varied with phosphoric acid the extent of colony growth of Rhizopus nigricans plotted against ...

UNLABELLED Phosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear layer. OBJECTIVES The purpose of this study was to compare the antimicrobial and cytotoxic effects of a 37% phosphoric acid solution to other irrigants commonly used in endodontics. MATERIAL AND METHODS The substances 37% phosphoric acid, 17% EDTA, 10% citric acid, 2% chlorhexidine (s...

OBJECTIVE The purpose of this study was to compare the etching effects of a self-etching primer with 37% phosphoric acid on enamel by using a scanning electron microscope. Bond strength and the site of bond failure were also determined for brackets bonded using SEP and 37% phosphoric acid. MATERIALS AND METHODS A total of 60 maxillary premolar teeth were used for this study and they were divi...

In this study, extraction of amoxicillin (AMOX) ions from aqueous solution by liquid-liquid extraction (LLE) was investigated. The LLE process by response surface methodology (RSM) was carried out based on central composite design (CCD). The organic phase consisted of extractant and toluene as diluent. In this process, triethylamine (TEA), di-2-ethylhexyl phosphoric acid and mono-2-ethylhexyl p...

The resistance of white spot lesions to acid demineralization when etched with phosphoric acid and sealed with a resin material was studied. Artificially created white spot lesions were sealed and re-exposed to an artificial caries medium along with unprotected white spot lesions. Examination with polarized light microscopy revealed continued progression of the unprotected white spot lesions, w...

Two high-performance liquid chromatography (HPLC) methods for ascorbic acid (AA) quantification were compared in three cultivars of melon (Cucumis melo L.) fruits. Both procedures were analogous except for the extraction medium used: 6 % meta-phosphoric acid and 3 % citric acid. The general conclusion is that 3 % citric acid is a better extraction medium compared to 6 % meta-phosphoric acid and...