Nitrates cerium

Greek lanthanein, to lie hidden) Mosander in 1839 extracted a new earth lanthana, from impure cerium nitrate and recognized the new element. 

Four years before isolating yttria, Mosander extracted lanthanum oxide as an impurity from cerium nitrate (hence the name from Greek XavOaveiv, to hide), but it was not until 1923 that metallic lanthanum in a relatively pure form was obtained, by electrolysis of fused halides. 

The photochemical cyclisation of p.y-unsaturated ketoximes to 2-isoxazolines, e.g., 16—>17, has been reported <95RTC514>. 2-Isoxazolines are obtained from alkenes and primary nitroalkanes in the presence of ammonium cerium nitrate and formic acid <95MI399>. Treatment of certain 1,3-diketones with a nitrating mixture generates acyl nitrile oxides, which can be trapped in situ as dipolar cycloadducts (see Scheme 3) <96SC3401>. 

The precipitate from cerium nitrate and sodium azide is explosive. See other metal azides... 

In studies with normal adult animals, orally administered radiocerium moves rapidly through the gastrointestinal tract. About 0.96 of a cerium nitrate solution administered orally to rats was excreted within 24 hours (Sagan and Lengemann, 1973). However, external irradiation of the gastrointestinal tract with a 137Cs source (800 R) delayed excretion of the radiocerium. Only about 0.85 of the administered cerium was excreted by 3 days but 0.992 was excreted by 4 days. In swine, 0.98 of an oral dose of radiocerium was excreted by 3 days (Miller et al., 1969) while in cattle, radiocerium placed in the rumen required 3.7 days for 0.9 of the dose to be excreted. Fecal excretion of the cerium still occurred after 4 days. When radiocerium was placed in the abomasum of cattle, it was almost entirely voided in 1.2 days. 

HN03, heat, NaNOz b R = Me, ammonium cerium nitrate, reflux... 

A number of mineral-based substances display an adjuvant effect. Although calcium phosphate, calcium chloride and salts of various metals (e.g. zinc sulfate and cerium nitrate) display some effect, aluminium-based substances are by far the most potent. Most commonly employed are aluminium hydroxide and aluminium phosphate (Table 13.13). Their adjuvanticity, coupled to their proven safety, render them particularly valuable in the preparation of vaccines for young children. They have been incorporated into millions of doses of such vaccine products so far. 

FIGURE 6.11 Diagram of the processing technique used to prepare Cu-Ce02-YSZ anodes for direct oxidation of hydrocarbon fuels by preparing a porous preform of YSZ and then infiltrating it with cerium nitrates to form ceria and then with copper nitrates to form metallic copper [84]. Reprinted from [84] with permission from Elsevier. 

Ronning, Holmen, and coworkers—Ce doping of Cu/Zn/Al catalysts improves stability. Ronning et al,339 explored the impact of ceria addition to Cu/ZnO catalysts. Catalysts were prepared by co-precipitation of Cu, Zn, and Al from their corresponding nitrates. Ceria was incorporated into the catalyst by impregnation of cerium nitrate either before or after calcination (6 hours at 350 °C or 400 °C). The chemical compositions of the resulting catalysts are reported in Table 62. 

Cerium was the first rare-earth element discovered, and its discovery came in 1803 by Jons Jakob Berzelius in Vienna. Johann Gadohn (1760—1852) also studied some minerals that were different from others known at that time. Because they were different from the common earth elements but were all very similar to each other, he named them rare-earth elements. However, he was unable to separate or identify them. In the 1800s only two rare-earths were known. At that time, they were known as yttria and ceria. Carl Gustav Mosander (1797—1858) and several other scientists attempted to separate the impurities in these two elements. In 1839 Mosander treated cerium nitrate with dilute nitric acid, which yielded a new rare-earth oxide he called lanthanum. Mosander is credited with its discovery. This caused a change in the periodic table because the separation produced two new elements. Mosander s method for separating rare-earths from a common mineral or from each other led other chemists to use... 

Thorium nitrate is a reagent for measuring fluorine and for making thori-ated tungsten filaments. Thorium nitrate containing 1% cerium nitrate is the impregnating liquid in making incandescent gas mantles. 

In 1839 Mosander heated some cerium nitrate and treated tire partly decomposed salt with dilute nitric acid. In the extract he found a new earth, which he named lanthana, meaning hidden, meanwhile retaining the old name, ceria, for the oxide which is insoluble in dilute nitric acid (7, 28, 45). In the same year, Axel Erdmann, one of Sefstrom s students, discovered lanthana in a new Norwegian mineral, which he named mosan-drite in honor of Mosander. 

When the Swedish chemist Carl Gustav Mosander discovered lanthanum in 1839, he had no idea what he had started. He extracted it as its oxide - an earth - from cerium nitrate. Mosander s colleague Berzelius suggested the name, from the Greek... 

Pour 1 ml of cerium nitrate into a test tube and add a few drops of sodium hydroxide. What happens Write the equation of the reaction. Act on the precipitate with an excess amount of the sodium hydroxide. Does cerium hydroxide react with sodium hydroxide ... 

Add a sodium carbonate solution to a cerium nitrate one. What do you observe Write the equation of the reaction. How do mineral acids react with the obtained salt ... 

Cerium Nitrate or Cerous Nitrate. See under Nitrates... 

The use of complex cerium nitrate (IV) (which is more accessible in comparison with (PyH)2CeCl6) in the synthesis of Ce(OR)4 piovedquite fruitful ... 

Hirakawa K. 1983. Determination of silver and cerium in the liver and the kidney from a severely burned infant treated with silver sulfadiazine and cerium nitrate. Radioisotopes 32 59-65. 

Cleaning of SPR glass slides (optical grade SF2, refractive index 1.65, from UQG Optical Components). Sonicator (e.g., Lucas Dawe sonication bath) and different solutions hydrochloric acid/nitric acid 3 1 v/v (solution A) ammonium cerium nitrate (1M) (solution B) sulfuric acid/hydrogen peroxide 1 1 (Piranha solution) isopropanol. Use caution in handling these solutions harmful and corrosive. 

An excellent review on this aspect appeared in the literature [172]. Cerium salts have proved to be a useful antiseptic for external application to wounds [162]. Treatment of bums was achieved by using a mixture of cerium nitrate and silver sulfadiazine [173]. 

Cerium Impregnation. All of the above spinels were impregnated(1) by cerium nitrate hexahydrate. A portion (87.7 g) of the spinel prepared by any of the above methods was impregnated with a solution containing 42.9 g of 70% Ce(N03)3.6H20 (Ce02 content 28.7%) and 40 g water. This material was dried at 120°C for 3 h and calcined at 700°C for 1 h. 

It was one of Berzelius assistants and the curator of the mineral collections of the Stockholm Academy of Sciences, Carl Gustaf Mosander (1797-1858), who demonstrated the complexity of both "yttria" and "ceria." When Mosander heated some "cerium" nitrate in 1839, the salt partly decomposed, and on a treatment with dilute nitric acid, he succeeded in extracting a new earth. He called the new element lanthanum (German Lanthan) and its oxide "lanthana." Mosander retained the old name ceria (Ce) for the insoluble portion of the "ceric" oxide in nitric acid. 

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