Sulfate, oxidation

Propyn-l-ol Alkali metals, mercury(II) sulfate, oxidizing materials, phosphorus pentoxide, sulfuric acid... 

Copper. Some 15 copper compounds (qv) have been used as micronutrient fertilizers. These include copper sulfates, oxides, chlorides, and cupric ammonium phosphate [15928-74-2] and several copper complexes and chelates. Recommended rates of Cu appHcation range from a low of 0.2 to as much as 14 kg/hm. Both soil and foHar appHcations are used. 

Quantitatively, sulfur in a free or combined state is generally determined by oxidizing it to a soluble sulfate, by fusion with an alkaH carbonate if necessary, and precipitating it as insoluble barium sulfate. Oxidation can be effected with such agents as concentrated or fuming nitric acid, bromine, sodium peroxide, potassium nitrate, or potassium chlorate. Free sulfur is normally determined by solution in carbon disulfide, the latter being distilled from the extract. This method is not useful if the sample contains polymeric sulfur. 

Attempts to obtain 5-nitro-l,7-naphthyridine and 3,6-dinitro-l,8-naph-thyridine (83) from the corresponding 8-chloro-5-nitro-l,7-naphthyridine and 2-chloro-3,6-dinitro-l,8-naphthyridine using the similar reaction failed (85JHC761 98MI2). However, 3,6-dinitro-l,8-naphthyridine (83) could be prepared in 21% yield by hydrazino-dechlorination of 2-chloro-3,6-dinitro-1,8-naphthyridine (82) and subsequent cupric sulfate oxidation of the intermediate 2-hydrazino-3,6-dinitro-l,8-naphthyridine (93LA471). 

In the previous paragraph, it has been stated that minerals have the same structure but different compositions (phenomenon of isomorphism of minerals) while some minerals have the same composition but different structures (phenomenon of polymorphism of minerals). Mineral composition and structure are both important in studying and classifying minerals. The major class of minerals - based on composition and structure - include elements, sulfides, halides, carbonates, sulfates, oxides, phosphates, and silicates. The silicate class is especially important, because silicon makes up 95% of the minerals, by volume, in the Earth s crust. Mineral classes are divided into families on the basis of the chemicals in each mineral. Families, in turn, are made of groups of minerals that have a similar structure. Groups are further divided into species. 

Franke [47] undertook a comprehensive electroanalytical study of K2S207 mixtures with K2S04, which is formed by Eqs. (47) and (48) and V2Os, a widely-used oxidation catalyst for S02. Pure pyrosulfate under N2 or air (Fig. 38a,b) shows only the reduction to S02 and sulfate, Eq. (48) (all potentials are vs. Ag/Ag+). When S02 is added, a new reduction and oxidation peak appear (Fig. 38c,d). When the electrolyte was pre-saturated with K2S04 (ca. 4 wt.%) (Fig. 39) the gas composition had no direct effect on the voltammetry. Although the equilibrium for Eq. (49) lies well to the right at this temperature, 400 °C, the kinetics are quite slow in the absence of a catalyst. The equilibrium between pyrosulfate and sulfate, Eq. (47), lies well to the left (K = 2 x 10-6), but will proceed to the right in the absence of S03. Thus, the new peaks are sulfate oxidation, Eq. (43), and S03 reduction to sulfite ... 

Traditionally, the production of LABs has been practiced commercially using either Lewis acid catalysts, or liquid hydrofluoric acid (HF).2 The HF catalysis typically gives 2-phenylalkane selectivities of only 17-18%. More recently, UOP/CEPSA have announced the DetalR process for LAB production that is reported to employ a solid acid catalyst.3 Within the same time frame, a number of papers and patents have been published describing LAB synthesis using a range of solid acid (sterically constrained) catalysts, including acidic clays,4 sulfated oxides,5 plus a variety of acidic zeolite structures.6"9 Many of these solid acids provide improved 2-phenylalkane selectivities. 

Potassium permanganate Potassium sodium alloy 2-Propyn-l-ol Organic or readily oxidizable materials Air, carbon dioxide, carbon disulfide, halocarbons, metal oxides Alkali metals, mercury(II) sulfate, oxidizing materials, phosphorus pentoxide, sulfuric acid... 

Several other supports have been used in order to generate more-electrophilic Zr systems, including sulfated zirconia [186], sulfated alumina [187], or other sulfated oxide supports [188], though the surface species are quite complex for these sys-... 

A number of 2H-1,2,3-triazole 1-oxides 72 were prepared by chemists at the Cassella Company as potential NO-donors in view of their formal structural similarity with furoxan derivatives [18]. Derivative 72a was studied in depth. It was obtained by cupric sulfate oxidation of intermediate 79, derived from the action of the substituted phenylhydrazine 78 on the oximino acetoacetic acid amide 77 (Scheme 6.13). 

Sulfated oxides, prepared by treating inorganic oxides such as AI2O3, Zr02, Ti02,... 

Phosphorus is one of the most widely distributed elements on earth. It is found as phosphate salts in nearly all igneous rocks and in sedimentary deposits and sea beds. Phosphorus occurs in more than three hundred minerals, usually associated with Ca, Mg, Fe, Sr, Al, Na, and several other metals, and with anions such as silicates, sulfates, oxides, hydroxides, and hahdes. 

The aqueous fluids formed by melting of ices in asteroids reacted with minerals to produce a host of secondary phases. Laboratory studies provide information on the identities of these phases. They include hydrated minerals such as serpentines and clays, as well as a variety of carbonates, sulfates, oxides, sulfides, halides, and oxy-hydroxides, some of which are pictured in Figure 12.15. The alteration minerals in carbonaceous chondrites have been discussed extensively in the literature (Zolensky and McSween, 1988 Buseck and Hua, 1993 Brearley, 2004) and were most recently reviewed by Brearley (2006). In the case of Cl chondrites, the alteration is pervasive and almost no unaltered minerals remain. CM chondrites contain mixtures of heavily altered and partially altered materials. In CR2 and CV3oxb chondrites, matrix minerals have been moderately altered and chondrules show some effects of aqueous alteration. For other chondrite groups such as CO and LL3.0-3.1, the alteration is subtle and secondary minerals are uncommon. In some CV chondrites, a later thermal metamorphic overprint has dehydrated serpentine to form olivine. 

Asteroids that formed beyond the snowline represent rock and ice accreted inside the orbit of Jupiter. The most distant asteroids may still contain ices, but many asteroids have been heated. Melting of ice produced aqueous fluids, which reacted with chondritic minerals at low temperatures to form secondary minerals (phyllosilicates, carbonates, sulfates, oxides). The alteration minerals can be discerned in asteroid spectra and characterized by analyses of chondrites derived from these bodies. 

Ferrocenylacetonitrile, 40, 4S Ferrous sulfate, oxidation ferf-butyl alcohol to a,a,a, a -tetramethyl tetra-methylene glycol by hydrogen peroxide and, 40, 90 Fluoboric acid as catalyst for diazomethane etherifications, 41, 9,10 Formaldehyde, reaction with diethyl malonate to form diethyl bis-(hydroxymethyl)malonate, 40, 27... 

Oxidation of sulfite to sulfate within cells occurs by a pathway through adenosine 5 -pHosphosulfate (APS, adenylyl sulfate). Oxidation via APS (Eq. 18-22) provides a means of substrate-level phosphorylation,... 

Side hydrazino groups can be effectively removed oxidatively by an appropriate and mild oxidizing agent. For example, copper(II) sulfate oxidizes 5,6,7,8-tetrafluoro-2,3-dihydrazino-quinoxaline to afford 5,6,7,8-tetrafluoroquinoxaline (Table 16).267... 

Cohall is present in vitamin Bi to Ihe extent of about 4ci-. Lack of cobalt in tlie soil and feedstuffs prevents tuniinants from synthesizing all of the vilamin B j for their needs. Thus, cobalt can be added to feedstuffs as the chloride, sulfate, oxide, nr carbonate. Excessive cobalt intakes are toxic, causing a reduction in feed intake and body weight, accompanied by emaciation, anemia, debility, and elevated levels of cobull in the liver. It is of interest to note that clinical coball tnxiciiy closely resembles clinical cobalt deficiency. 

Various solid acids were qualified in the literature as superacids on the basis of very different arguments. The most studied solid superacid, sulfated zirconia, and related sulfated oxides were considered as superacids because of their ability to convert w-butane into isobutane at low temperatures. 

The application of the Na2SO -Ln2(SO, -SiCLCLj Y and Gd) electrolyte samples as the solid electrolyte for an SC gas detector was investigated. The EMF measurements were conducted by both the SC gas concentration cell(33) and the solid reference electrode(34) methods. Several efforts have been concentrated on the development of the appropriate reference electrode. In our study, the sulfate-oxide solid reference electrode method was adopted. 

Substrates 1-3 are readily prepared with a few steps as illustrated in Scheme 4. After methylation of pyridine with dimethyl sulfate, oxidation with potassium ferricyanide in the presence of sodium hydroxide leads... 

Sulfate Oxides Hackerman and Stephens (1954), Rajan (1978), Tripathi et al. (1975)... 

Elemental Sulfur. In 1942, Chatterjee (44) reported the presence of elemental sulfur in weathered Indian coal but not in fresh samples. He suggested that, during weathering, pyrite is first oxidized to ferrous and ferric sulfates, and that then ferric sulfate oxidizes pyrite to elemental sulfur. The presence of elemental sulfur in U.S. coals was confirmed recently by Richard et al. (45) and White and Lee (46). Duran et al. (47) used extraction and gas chromatographic analysis to determine elemental sulfur in a suite of U.S. coals. They found that elemental sulfur (0.03-0.17%) is present in coal that has been exposed to the atmosphere, but is absent in pristine samples that have been processed and sealed under a nitrogen atmosphere. These data support Chatteijee s discovery that elemental sulfur in coal is a weathering product. 

Figure 2.11 Mechanism of the internal sulfite to sulfate oxidation showing the movement of the oxygen atoms (shown faded). The equatorial cluster belts and the central sulfur position of a W,l(SO,) fragment is illustrated (S atoms also faded).

Pathways 1-4 are known in various bivalve molluscs 2, 3, 8, and 9 are often utilized by helminths 5, 6, and 7, while theoretically possible in bivalve molluscs, do not appear to be utilized to any significant extent. Pathway 10, or sulfate oxidation of organic substrates, is well known to occur in the highly reduced layers of benthic silt, but the distribution of this activity between bacteria and lower invertebrate ani-... 

C. Y. Hsu, C. R. Heimbuch, C. T. Armes, and B. C. Gates, A highly active solid superacid catalyst for n - butane isomerization a sulfated oxide containing iron, manganese and zirconium, J. Chem. Soc. Chem. Commun. 1645-1646 (1992). 

Carboxylate complexes are often synthesized by refluxing the acid with the metal salts (such as carbonate, sulfate, oxide, etc.), or by reaction of the sodium or silver salt of the acid with the metal halide. Insertion of CO2 into a-bonded organotransition metal species has also been used to generate carboxylate complexes, as has exchange reactions with metal alkoxides (see Section 3.3). 

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