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In aqueous suspension

After preparation, colloidal suspensions usually need to undergo purification procedures before detailed studies can be carried out. A common technique for charged particles (typically in aqueous suspension) is dialysis, to deal witli ionic impurities and small solutes. More extensive deionization can be achieved using ion exchange resins. [Pg.2670]

Martin C, Weyerioh B, Biegei J, Deike R, Johner C, Kiein R and Weber R 1995 Eieotrio-fieid iight-soattering by rod-iike poiyeieotroiytes in aqueous suspensions J. Physique ii 5 697-719... [Pg.2691]

C. HIO is prepared by oxidation of iodine with perchloric acid, nitric acid, or hydrogen peroxide or oxidation of iodine in aqueous suspension to iodic acid by silver nitrate. Iodic acid is also formed by anodic oxidation at a platinum electrode of iodine dissolved in hydrochloric acid (113,114). [Pg.365]

Tetrabasic Lead Sulfate. Tetrabasic lead sulfate [12065-90-6] 4PbO PbSO, mol wt 1196.12, sp gr 8.15, is made by fusion of stoichiometric quantities of Htharge (PbO) and lead sulfate (PbSO heat of formation, Ai/ = — 1814 kJ/mol (—434.1 kcal/mol). Alternatively, tetrabasic lead sulfate may be prepared by boiling the components in aqueous suspensions. At about 70°C, tribasic hydrate reacts with lead oxide to form tetrabasic sulfate. At 80°C, this transformation is complete in - 20 hours. Tetrabasic lead sulfate is used in limited quantities in Europe as a PVC stabilizer. However, in the United States, lead-acid batteries have been developed by BeU Telephone Laboratories, which contain tetrabasic lead sulfate. Such batteries are used for emergency power at telephone switchboard stations and have an anticipated service life of over 50 years. [Pg.70]

Dime slury is a form of lime hydrate in aqueous suspension that contains considerable free water. [Pg.164]

Milk-of-lime is a dilute lime hydrate in aqueous suspension which has the consistency of milk. [Pg.164]

Structure Modification. Several types of stmctural defects or variants can occur which figure in adsorption and catalysis (/) surface defects due to termination of the crystal surface and hydrolysis of surface cations (2) stmctural defects due to imperfect stacking of the secondary units, which may result in blocked channels (J) ionic species, eg, OH , AIO 2, Na", SiO , may be left stranded in the stmcture during synthesis (4) the cation form, acting as the salt of a weak acid, hydrolyzes in aqueous suspension to produce free hydroxide and cations in solution and (5) hydroxyl groups in place of metal cations may be introduced by ammonium ion exchange, followed by thermal deammoniation. [Pg.447]

Binders in Ceramics, Powder Metallurgy, and Water-Based Coatings of Fluorescent Lamps. In coatings and ceramics appHcations, the suspension rheology needs to be modified to obtain a uniform dispersion of fine particles in the finished product. When PEO is used as a binder in aqueous suspensions, it is possible to remove PEO completely in less than 5 min by baking at temperatures of 400°C. This property has been successfully commercialized in several ceramic appHcations, in powder metallurgy, and in water-based coatings of fluorescent lamps (164—168). [Pg.344]

Small amounts of TAIC together with DAP have been used to cure unsaturated polyesters in glass-reinforced thermo sets (131). It has been used with polyfunctional methacrylate esters in anaerobic adhesives (132). TAIC and vinyl acetate are copolymerized in aqueous suspension, and vinyl alcohol copolymer gels are made from the products (133). Electron cure of poly(ethylene terephthalate) moldings containing TAIC improves heat resistance and transparency (134). [Pg.88]

The compound is odorless with a faintly acidic taste it is practically insoluble in water, ethanol and dilute acids but freely soluble in dilute aqueous alkaU with dissociation constants, pfC, 3.73, 7.9, 9.3. The compound is prepared by sodium hydrosulfite reduction of 3-nitro-4-hydroxyphenylarsonic acid [121 -19-7] and then acetylation in aqueous suspension with acetic anhydride at 50—55°C for 2 h (174,175). [Pg.314]

Starch in aqueous suspension may react to form diesters with phosphoms oxychloride, phosphoms pentachloride, and thiophosphoryl chloride... [Pg.345]

Until about 1950, the predominant method of producing industrial enzymes was by extraction from animal or plant sources by 1993, this accounts for less than 10%. With the exception of trypsin, chymosin, papain [9001 -73-2J, and a few others, industrial enzymes are now produced by microorganisms grown in aqueous suspension in large vessels, ie, by fermentation (qv). A smaH (5%) fraction is obtained by surface culture, ie, soHd-state fermentation, of microorganisms (13). [Pg.289]

Preservatives may inelude disinfeetant and antiseptic chemicals together with eertain compounds used almost exclusively as preservatives. They are added to mar industrial, including pharmaceutical, products which may, by their nature, support the growth of bacteria and moulds causing spoilage of the product and possibly infection of the user. In the field of pharmaceutical preservation, addition of an inhibitory substance to a multidose injection (Chapter 21) or the prevention of growth in aqueous suspensions ofdmgs intended for oral administration (Chapter 18) are prime examples. [Pg.251]

Fig. 5.14 Inoue et al. carried out a systematic study of the photocatalytic reduction of CO2 by different semiconductor powders in aqueous suspensions. Shown here is the energy correlation between semiconductor catalysts and redox couples in water, as presented in their paper. In principle, the solution species with more positive redox potential with respect to the conduction band level of the semiconductor is preferably reduced at the electrode. Photoexcited electrons in the more negative conduction band certainly have greater ability to reduce CO2 in the solution. (Reproduced from [240])... Fig. 5.14 Inoue et al. carried out a systematic study of the photocatalytic reduction of CO2 by different semiconductor powders in aqueous suspensions. Shown here is the energy correlation between semiconductor catalysts and redox couples in water, as presented in their paper. In principle, the solution species with more positive redox potential with respect to the conduction band level of the semiconductor is preferably reduced at the electrode. Photoexcited electrons in the more negative conduction band certainly have greater ability to reduce CO2 in the solution. (Reproduced from [240])...
Benniston AC, Haniman A (2008) Artificial photosynthesis. Materials Today 11 26-34 Inoue T, Fujishima A, Konishi S, Honda K (1979) Photoelectrocatalytic reduction of carbon dioxide in aqueous suspensions of semiconductor powders. Nature 277 637-638 Halmann M (1978) Photoelectrochemical reduction of aqueous carbon dioxide on p-type gallium phosphide in liquid junction solar cells. Nature 275 115-116 Heminger JC, Carr R, Somorjai GA (1987) The photoassisted reaction of gaseous water and carbon dioxide adsorbed on the SrH03 (111) crystal face to form methane. Chem Phys Lett 57 100-104... [Pg.303]

Photoreactions on ZnO powder in aqueous suspension and in contact with gases have often been studied during the last few decades, and only a few aspects of this work are reviewed here. For example, nitrous oxide and methyl iodide were found to decompose when brought into contact at 20 °C with the illuminated surface of ZnO and nitrate, indigo carmine and p-nitrosodimethylaniline were found to be reduced in aqueous suspensions ZnO is of special interest as it is one of the standard electrode materials in conventional semiconductor electrochemistry and photo-electrochemistry Colloidal ZnO has not been available until recently. It... [Pg.160]

Acute Toxicity. The LD50 following oral administration of parathion, either in propylene glycol solutions or in aqueous suspensions of the 15% wettable powder, has been determined for rats, mice, and guinea pigs. The lethal dose was approximated for rabbits and dogs. The results of these experiments are summarized in Table I. Statistical evaluation was by the method of Wilcoxon and Litchfield (11). [Pg.31]

Chlorine adds to form the Zrans-dichloride bromine adds, in carbon tetrachloride solution, to give a mixture of as- and trans-dibromides this addition can be directed wholly to the trans derivative by conducting the bromination in a mixed phase reaction in aqueous suspension. [Pg.177]

Fig. 14 Mean plasma phenacetin concentrations in six adult volunteers following administration of 1.5-g doses (in aqueous suspensions containing 200 mg of phenacetin per milliliter). (From Ref. 18.). Fig. 14 Mean plasma phenacetin concentrations in six adult volunteers following administration of 1.5-g doses (in aqueous suspensions containing 200 mg of phenacetin per milliliter). (From Ref. 18.).
JE Carless. Dissolution and crystal growth in aqueous suspension of cortisone acetate. J Pharm Pharmacol... [Pg.286]

SA Young, G Buckton. Particle growth in aqueous suspensions the influence of surface energy and polarity. Int J Pharm 60 235-241, 1990. [Pg.286]

WW Young, R Suryanarayanan. Kinetics of transition of anhydrous carbamazepine to carbamazepine dihydrate in aqueous suspensions. J Pharm Sci 80(5) 496-500, 1991. [Pg.619]

Thus, in contrast to previous in vivo models, this in vitro model provides the possibility of dissociating experimentally two important processes of the intestinal carotenoid absorption cellular uptake and secretion. Under conditions mimicking the postprandial state (TC OA supplementation), differentiated Caco-2 cells were able (1) to take up carotenoids at the apical side and to incorporate them into CM and (2) to secrete them at the basolateral side, associated with CM fractions. In this model, no attempt has yet been made to reproduce the in vivo physiochemical conditions occurring in the intestinal lumen, such as carotenoid release from the food matrix and solubilization into mixed lipid micelles. Carotenoids were delivered to Caco-2 cells in aqueous suspension with Tween 40 (During et al., 2002). Using this cell culture system in conjunction with an in vitro... [Pg.370]

Augugliaro V, Baiocchi C, Prevot AB, Garcia-Lopez E, Loddo V, Malato S, Marci G, Palmisano L, Pazzi M, Pramauro E (2002) Azo-dyes photocatalytic degradation in aqueous suspension of Ti02 under solar irradiation. Chemosphere 49 1223-1230... [Pg.332]

Inoue, T., Fujishima, A., Konishi, S., and Honda, K. (1979) Photoelectrocatalytic reduction of carbon dioxide in aqueous suspensions of semiconductor powers. Nature, 277 (5698), 637-638. [Pg.133]

Palmisano, G., Yurdakal, S., Augugliaro, V., Loddo, V., and Palmisano,L. (2007) Photocatalytic selective oxidation of 4-methoxybenzyl alcohol to aldehyde in aqueous suspension of home-prepared... [Pg.134]

Ohtani, B., Iwai, K., Kominami, H., Matsuura, T., Kera, Y., and Nishimoto, S. (1995) Titanium(IV) oxide photocatalyst of ultra-high activity for selective N-cyclization of an amino acid in aqueous suspensions. Chemical Physics Letters, 242 (3), 315-319. [Pg.135]

Anandan, S., Vinu, A., Mori, T., Gokulakrishnan, N., Srinivasu, P., Murugesan, V. and Ariga, K. (2007) Photocatalytic degradation of 2,4,6-trichlorophenol using lanthanum doped ZnO in aqueous suspension. Catalysis Communications, 8, 1377-1382. [Pg.243]

Red phosphorus and the chlorite react very exothermally in aqueous suspension above 50°C, and there may be a sudden and near-explosive stage in the redox reaction after an induction period. [Pg.1391]

Early studies focused on the behavior of molecular rotors in vesicles [128] and lipid bilayers [18, 26]. Humphrey-Baker et al. [128] found that an indocyanine dye associates with micellar systems in aqueous suspension. The dye migrates into the micelles and shows an increased quantum yield and a bathochromic shift of emission. Although Humphrey-Baker et al. identify modulation of the quantum... [Pg.295]


See other pages where In aqueous suspension is mentioned: [Pg.177]    [Pg.322]    [Pg.2670]    [Pg.34]    [Pg.130]    [Pg.350]    [Pg.352]    [Pg.54]    [Pg.72]    [Pg.1204]    [Pg.1057]    [Pg.665]    [Pg.135]    [Pg.172]    [Pg.78]    [Pg.604]    [Pg.308]    [Pg.365]    [Pg.173]    [Pg.28]    [Pg.186]   
See also in sourсe #XX -- [ Pg.431 , Pg.461 ]




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