Baso-form

Ln(II) in LnFj Ln(II) were determined after samples dissolution in H PO in the presence of a titrated solution of NFI VO, which excess was titrated with the Fe(II) salt. It was found that dissolution of the materials based on CeF CeFj in H PO does not change the oxidation state of cerium, thus phosphate complexes of Ce(III, IV) can be used for quantitative spectrophotometric determination of cerium valence forms. The contents of Ln(II, III) in Ln S LnS may be counted from results of the determination of total sulfur (determined gravimetric ally in BaSO form) and sum of the reducers - S and Ln(II) (determined by iodometric method). 

In the classic Griess test, use is made of sulfanilic acid (I), with subsequent coupling of the resulting diazonium compound with a-naphthylamine (II), to give the red -benzene sulfonic acid-azo-a-naphthylamine (HI), here shown in its baso-form, to produce the red, water-soluble azo dye (IV). 

In contrast to its parent substance, (weakly basic colorless diphenyl-amine), hexanitrodiphenylamine (I) is an acid which dissolves in sodium hydroxide or carbonate to produce orange-red solutions. This color change is due to a change in structure. Hydroxyl ions convert the baso-form of dipicrylamine (I) into the aci-form (II), in which a continuous chain of conjugated double bonds effects the deepening of color. ions convert the orange-red aci-form to the bright yellow water-insoluble baso-form ... 

Ammonium dipicrylaminate is precipitated by considerable quantities of ammonium salts, but the latter, as well as all TP halides can be removed by igniting the material to be tested. Other metal ions show no reaction, or they are precipitated as hydroxides or basic salts by the sodium dipicryl-amine solution, which acts as an alkali because it is hydrolyzed in part. In such instances, dipicrylamine is precipitated in its water-insoluble, non-reactive baso-form (I). Consequently, considerable quantities of metal ions, which of themselves are imable to produce colored dipicrylaminates, can nevertheless impair the test for potassium by lowering the concentration of the aci-form (II), which is necessary for the precipitation of potassium. Therefore, if potassium is to be detected in the presence of considerable amounts of metal ions, which can be precipitated as hydroxides, it is better to warm the test solution beforehand with mercuric oxide to precipitate these ions as hydroxides. The filtrate from this preliminary step, or parts of it, is evaporated, ignited, and the ignition residue then tested for potassium. 

Ziac sulfate was made by 15 companies ia 1980 from secondary materials (93%) and from roasted ore, ie, ziac oxide (7%). The ziaciferous material reacts with sulfuric acid to form a solution, which is purified. After filtration, the solution is heated to evaporation and heptahydrate crystals are separated. It is sometimes sold ia this form but usually as the monohydrate [7446-19-7] which is made by dehydration at ca 100°C. Very pure ziac sulfate solution is made ia the manufacture of the pigment Hthopone [1345-05-7] ZnS-BaSO, and of ziac by electrowinning (see ZiNC AND ZINC ALLOYS). 

In its natural form, barium [7440-39-3] Ba, never occurs as the metal but is almost always found as the ore barite [13462-86-7] BaSO. More than 90% of all barium is actually used as the ore, albeit after preliminary beneftciation. The petroleum industry consumed 90% of the ore for oil- and gas-weU drilling duids (muds). The other 10% is used as filler and/or for extender uses and the manufacture of all other barium chemicals. Witherite, the only other significant natural barium ore, is not mined commercially (1). The quantity of U.S. barium chemicals produced in 1986 and 1987 is given in Table 1. 

Barium sulfate [7727-43-7] BaSO, occurs as colorless rhombic crystals, mp 1580 °C (dec) sp gr 4.50 solubihty 0.000285 g/100 g H2O at 30°C and 0.00118 at 100°C. It is soluble in concentrated sulfuric acid, forming an acid sulfate dilution with water reprecipitates barium sulfate. Precipitated BaSO is known as blanc fixe, prepared from the reaction of aqueous solutions of barium sulfide and sodium sulfate. 

Paste Mixing. The active materials for both positive and negative plates are made from the identical base materials. Lead oxide, fibers, water, and a dilute solution of sulfuric acid are combined in an agitated batch mixer or reactor to form a pastelike mixture of lead sulfates, the normal, tribasic, and tetrabasic sulfates, plus PbO, water, and free lead. The positive and negative pastes differ only in additives to the base mixture. Organic expanders, barium sulfate [7727-43-7] BaSO carbon, and occasionally mineral oil are added to the negative paste. Red lead [1314-41 -6] or minium, Pb O, is sometimes added to the positive mix. The paste for both electrodes is characterized by cube weight or density, penetration, and raw plate density. 

The stmcture of boron phosphate prepared under normal atmospheric conditions consists of tetragonal bipyrimids analogous to the high cristobahte form of siUca. Both the boron and phosphoms are tetrahedraHy coordinated by oxygen. Similar siUcalike stmctures ate found for BAsO and TaBO (156). A quart2like form of boron phosphate can be prepared by heating the common form to 500°C at 5.07 GPa (50,000 atm) (157). 

The procedure for purification of Na,K-ATPase in membrane-bound form from the outer renal medulla of mammalian kidney offers the opportunity of exploring the structure of the Na,K-pump proteins in their native membrane environment. The protein remains embedded in the membrane bilayer throughout the purification procedure thus maintaining the asymmetric orientation of the protein in the baso-lateral membrane of the kidney cell in the purified preparation. This preparation has been particularly useful in studies of ultrastructure, protein conformation and for... 

The presence of a transporter can be assessed by comparing basolateral-to-apical with apical-to-basolateral transport of substrates in polarized cell monolayers. If P-gp is present, then basolateral-to-apical transport is enhanced and apical-to baso-lateral transport is reduced. Transport experiments are in general performed with radioactively labeled compounds. Several studies have been performed with Caco-2 cell lines (e.g. Ref. [85]). Since Caco-2 cells express a number of different transporters, the effects measured are most probably specific for the ensemble of transporters rather than for P-gp alone. P-gp-specific transport has been assayed across confluent cell layers formed by polarized kidney epithelial cells transfected with the MDR1 gene [86], Figure 20.11 shows experimental data obtained with these cell lines. A rank order for transport called substrate quality was determined for a number of compounds [86]. The substrate quality is a qualitative estimate, but nevertheless allows an investigation of the role of the air/water (or lipid/water) partition coefficient, log Kaw, for transport as seen in Fig. 20.11(A). For most of the compounds, a linear correlation is observed between substrate quality and log Kaw- However, four compounds are not transported at all despite their distinct lipophilicity. A plot of the substrate quality as a function of the potential of a... 

Other inorganic crystals studied by Mark and his collaborators, sometimes leading to complete structure determinations, include strontium chloride, zinc hydroxide, tin tetraiodide, potassium chlorate, potassium permanganage, and ammonium ferrocyanide. Minerals investigated by them include CaSO (anhydrite), BaSO (barite), PbSO, Fe2TiO[j (pseudobrookite), and three forms of Al2Si05 (cyanite, andalusite, and sillimanite). 

When boraetc add is added, it forms boro-silicates, often more fusible, moro ductile, easier to work, and producing loss waste, especially in table-ware and plate-glass manufacture. M. Paves remarks that the experiments undertaken, by Mil. Hae9 and Clkman-DOT on crystal, with a baso of oxide of zinc, yielded products remarkable for their whiteness, their transparency, their hardness, and the brilliant reflection of their cut faces. 

Analysis op Waters.—Method of Testing for and Determining Nitrous and Nitric Acids.—Almost all river waters, and. especially the shallow well waters of towns, contain, variable quantities of nitrons and nitric acids generally in combination with lime, as nitrite and nitrate of that baso. Their constituents have hitherto been generally overlooked by analysts, hut on their presence and quantity the chemist may form a more correct idea as to the Contamination of the water by organic matter than by, any other means. The Editor, therefore, attaches the greatest importance to the determination of these constituents, especially when the water is selected for domestic use. 

Sulphurous Acid.—200 c.c. of the beer, acidified with 5 c.c. of syrupy phosphoric acid, are distilled in a current of carbon dioxide, about 100 c.c. of distillate being collected in 50 c.c. of iodine solution (5 grams of iodine and 7-5 grams of potassium iodide per litre). The iodine solution is afterwards acidified with hydrochloric acid and boiled to expel the excess of iodine, the sulphuric acid formed being then precipitated by means of barium chloride. The presence of more than traces of sulphates indicates the addition of sulphite or sulphurous acid to the beer in such case, the barium sulphate is collected and weighed as usual BaSO X 1-372 = weight of SO per litre of the beer. 

Determination of the sulfate content requires the preliminary hydrolysis of galac-tans by the action of 1 M HC1 at 100 °C for 6 h (hydrolysis in 2 M trifluoroacetic acid can also be used for simultaneous determination of monosaccharides and sulfate). Quantitative estimation of sulfate in hydrolyzates can be performed by many methods known from inorganic analytical chemistry,218,219 but the most popular procedure in the case of galactans is turbidimetry of stabilized suspensions of BaSO.4. It was suggested in the early 1960s220 and is widely used at present in the slightly modified form.221... 

The XRD analysis results of the supports and catalysts are shown in Table 2. Figure 3 is the XRD pattern of the catalyst. The results indicate that Ti02 mainly exists in the form of anatase at the content of 93-95% and exists as rutile if the content is less than 1.0%. The content of BaSO is about 2.9-4.5% and rest is about 1%. The content of Ru in the catalyst is approximately 2%. The crystal structure of the surface-treated support is the same as the un-treated one. When 2% of Ru is loaded on the supports, the diffiaction... 

Since mtno acids contain both an acidic and A basic group. t tey an intramolecular acid-baso ZBACtioR and exist primarily in the form dipolar ion. or zwitterion (Oermnn zivittei hybrid" ... 

Na SO is available in two types, anhydrate and decahydrate. Its content analysis can be conducted based on the precipitation method using barium chloride (BaCl ). An excess amount of bariiun chloride is added into the sample solution which has been filtered beforehand to form BaSO, precipitate as indicated by the following reaction ... 

Indicators are (apparent) weak acids or bases of which the iono genic (a< - or baso- respectively) form possesses a color and constitution different from the color and structure of the pseudo- or normal compound. 

TNAP is expressed in human hepatocytes, and bile acids increase its activity [93] and secretion in the bile [94]. TNAP in rat hepatocytes is predominantly localized in the bile canalicular domain of the plasma membrane [95, 96], but can be addressed to the baso-lateral membrane in the presence of high levels of bile acid [97]. In contrast, mouse hepatocytes do not express TNAP [98]. In humans, liver TNAP may be expressed both at the sinusoidal and biliary pole of the hepatocyte. This explains why a significant proportion of TNAP activity in the circulation of healthy individuals originates from the liver. TNAP serum levels are of major clinical relevance as a marker of cholestasis. AP levels increase due to retrograde reflux of biliary alkaline phosphatase, enhanced hepatic synthesis and enzyme release into the serum, and induction of the intestinal alkaline phosphatase form [94, 99, 100]. 

Cell death due to apoptosis or necrosis is not the only form of tubular injury in ARF. There is also sub-lethal injury causing cell dysfunction. For example, alterations in proximal tubular cell polarity occm during renal ischemia. Tubule polarity is essential for its primary function of selective reabsorption of ions from the tubular fluid. Sodium-potassium-ATPase (Na-K-ATPase), the enzyme, normally localized to the baso-lateral membrane, maintains tubular polarity by regulation of cellular transport sodium and potassium in proximal tubules. Na-K-ATPase is linked to the cytosk-eleton/ membrane complex by a variety of proteins including spectrin. It has been demonstrated that in early reperfusion period spectrin dissociates from the cytosk-eleton and NaK-ATPase moves from the basolateral membrane into the cytoplasm and apical membrane [39-43]. 

Barium Sulphate—BaSO,—232.8—occurs in nature as heavy ifpar and is formed as an amorphous, white powder, insoluble in acids, by double decomposition between a Ha salt and a sulphate in solution. It is insoluble in BLO and in acids. It is used os a pigment, permanent white. 

---