Lanthanum salts

With our calcium example, the substance that accomplishes this is lanthanum. Lanthanum sulfates and phosphates are more stable than the corresponding calcium salts, and thus the calcium is free to atomize when lanthanum is present. Thus, analyses for calcium usually include addition of a lanthanum salt to the sample and standards. 

Lanthanum chloride is used to prepare other lanthanum salts. The anhydrous chloride is employed to produce lanthanum metal. 

Lanthanum hydroxide is used to prepare other lanthanum salts. 

The nitrate is used as an analytical standard as a matrix modifier in furnace AA analysis and for preparing other lanthanum salts. 

All the determined crystal structures exhibited hexagonal arrays of metal-metal interactions with diagonal interactions in the layer. All the lanthanum salts and the europium one were isostructural. 

If nitrogen and/or sulphur is present, acidify 3-4 ml of the fusion solution with dilute nitric acid and evaporate to half the original volume in order to expel any HCN and/or H2S which may be present. If nitrogen and sulphur are absent, proceed directly with 2 ml of the sodium fusion filtrate. Render the solution just neutral to litmus by the addition of dilute (5 m) aqueous ammonia solution, then add 5 drops of 5 m acetic acid and 20 mg of lanthanum chloranilate (2,5-dichloro-3,6-dihydroxy-p-benzoquinone, lanthanum salt) and shake intermittently for 10-15 minutes. Filter. A pink-violet coloration of the filtrate is a positive test for fluorine. 

Abstract. Free-volume structure in the lanthanum salt of laurinic acid in crystalline and liquid-crystalline states and an effect of dissolved Cgo molecules on the mean nanovoid radius and concentration were studied by means of the positron annihilation technique. La(Ci2H25COO)3 clathrate compound with dissolved C6o molecules was obtained, which is thermodynamically more stable than a simple mixture of components. Increased mean nanovoid radius (from 0.28 to 0.39 nm) after the inclusion of C6o molecules and concomitant decrease of the positronium annihilation rate by a factor of 2.7 indicate the decrease of the smallest nanovoid concentration. 

Abstract. Free volume structure in the lanthanum salt of laurinic acid in crystalline and liquid-crystalline states and an effect of dissolved C60 molecules on the mean... 

For a reaction with nitric acid and a lanthanum salt, see Parac-Vogt, T.N. Binnesmans, K. Tetrahedron Lett. 2004, 45, 3137. 

The Ca -ATPase piays an essential role In the pumping of calcium out of cells, and in the control of its cytosolic concentration. In the heart, the role of the pump is minor with respect to that of the sodium-calcium exchanger, but is most probabiy predominant in skeletal and smooth muscle. The pump is encoded by four independent genes, showing different patterns of tissue-specific expression and alternative splicing of the primary transcripts. The intracellular Ca pump proteins from skeletal muscle sarcoplasmic reticulum (SR), cardiac SR and brain microsomes are similar. Thapsigargin is a potent inhibitor, also lanthanum salts inhibit the pump at most sites. 

The decompositions of the light lanthanide [81] oxalates (613 to 713 K), were generally similar to that described above for the lanthanum salt. The relative stabilities of these six salts, and also of the normal and basic carbonates, is Gd > Sm > Nd > La > Pr > Ce. With few exceptions, the intermediates (identified by composition and infi-ared measurements) were ... 

Use Lanthanum salts, electronic devices, pyrophoric alloys, rocket propellants, reducing agent catalyst for conversion of nitrogen oxides to nitrogen in exhaust gases (usually in combination with cobalt, lead, or other metals), phosphors in x-ray screens. 

Yttrium ( Y) (1 = H2). The reaction of periodic acid or alkali-metal periodates with aqueous solutions of scandium, yttrium or lanthanum salts... 

Thorium salts have a, bactericidal and antitoxic action, as is shown by experiments with guinea pigs. Ten pigs which had received twice the lethal dose of cholera survived when treated with thorium or lanthanum salts, while the control pigs not so treated died within 30-36 hours.1 A solution containing 0.5-1.0 gram of thorium sulfate per liter is as toxic to lower organisms and ferments as mercuric chloride.2... 

Calcium binding was assayed by ultrafiltration and was found to exhibit a />H optimum at about 7.4. One class of binding sites is present which bind one mole of calcium per mole of protein with a dissociation constant equal to 2.5 X 10 5M. Calcium binding was competitively inhibited by other divalent cations the binding affinity being Ca++, Mn++, Sr++, Ba++, Mg++ (160). Lanthanum salts irreversibly precipitate brain CBP-II. Those cations which are the most effective inhibitors of calcium binding to this protein are also the most active for in vitro calcium-dependent release of neurotransmitters. 

Hydroxide, La(OII white, amorphous predp, prepd by adding excess of caustic alkali to a lanthanum salt soln. Strongly basic, displaces ammonia from ammonium salts, absorbs CO, from air- On dehydration yields La,0,.Hz0. 

Sulfate, La SQ,)], nonahydrate. hexagonal prisms. Prepd by treating a lanthanum salt with a slight excess of sulfuric add. Dec at white heat. Is the least sol of the rare earth sulfates soly in water decreases with increase in temp. Inso) in ale. Forms double salts with alkali or ammonium hydroxide. Anhydr salt prepd by heating hydrate. LDg, in rats > 5000 g/kg orally 275 mg/kg i.p. (Cochran). 

Hayashi, Danzuka, and Ueno (13) described the use of the lanthanum salt for phosphate determination... 

Maohata and Binder (Ml) reported that, with a graphite atomizer, matrix effects caused by iron in blood caused calibration curves to be rather flat (nonlinear) and results to be imprecise. These matrix effects were avoided by the addition of lanthanum salts. 

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