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Partial removal

Fieser s solution An aqueous alkaline solution of sodium anthraquinone -sulphonale (silver salt) reduced with sodium dithionite, Na2S204, and used as a scrubbing solution for partially removing O2 from, e.g., N2. [Pg.174]

Two other examples will sufhce. Methane physisorbs on NaCl(lOO) and an early study showed that the symmetrical, IR-inactive v mode could now be observed [97]. In more recent work, polarized FTIR rehection spectroscopy was used to determine that on being adsorbed, the three-fold degeneracies of the vs and v modes were partially removed [98]. This hnding allowed consideration of possible adsorbate-adsorbent geometries one was that of a tripod with three of the methane hydrogens on the surface. The systems were at between 4 and 40 K so that the equilibrium pressure was very low, about 10 atm. [Pg.635]

Aromatic and Nonaromatic Hydrocarbon Separation. Aromatics are partially removed from kerosines and jet fuels to improve smoke point and burning characteristics. This removal is commonly accompHshed by hydroprocessing, but can also be achieved by Hquid-Hquid extraction with solvents, such as furfural, or by adsorptive separation. Table 7 shows the results of a simulated moving-bed pilot-plant test using siHca gel adsorbent and feedstock components mainly in the C q—range. The extent of extraction does not vary gready for each of the various species of aromatics present. SiHca gel tends to extract all aromatics from nonaromatics (89). [Pg.300]

Drying. In many cases, the high moisture content of young coals dictates significant drying (qv) before use. In some cases, partial removal of mineral matter, especially water-soluble species, is desirable. [Pg.155]

Evaporated milk is a Hquid product obtained by the partial removal of water only from milk. It has a minimum milk-fat content of 7.5 mol % and a minimum milk-solids content of 25.0 mol %. Evaporated skimmed milk is a Hquid product obtained by the partial removal of water only from skimmed milk. It has a minimum milk-solids content of 20.0 mol %. Sweetened condensed milk is a product obtained by the partial removal of water only from milk with the addition of sugars. It has a minimum milk-fat content of 8.0 mol % and a minimum milk-solids content of 28.0 mol %. Skimmed sweetened condensed milk is a product obtained by the partial removal of water only from skimmed milk with the addition of sugars. It has a minimum milk-solids content of 24.0 mol %. AH may contain food additives (qv) as stabilizers, in maximum amounts, including sodium, potassium, and calcium salts of hydrochloric acid at 2000 mg/kg singly citric acid, carbonic acid, orthophosphoric acid, and polyphosphoric acid at 3000 mg/kg in combination, expressed as anhydrous substances and in the evaporated milk carrageenin may be added at 150 mg/kg. [Pg.365]

Infusion. Infusion botanical extracts are tinctures that have been concentrated by either total or partial removal of the alcohol by distillation. [Pg.296]

Commercially, a small amount of the 4,4 -MDA is isolated by distillation from PMDA. Depending on the process employed, the removal of MDA can be partial (as is done with the isocyanates) or total. Partial removal of MDA gives some processiag latitude but yields of 4,4 -MDA are reduced. Distillation residues from PMDA manufacture that contain less than 1% MDA pose a disposal problem. Processes for the regeneration of MDA by heating these residues ia the presence of aniline and an acid catalyst have been patented (33—35). Waste disposal of PMDA is expensive and reclamation processes could become commercially viable. The versatility of the isocyanate process, however, can be used to avoid the formation of low MDA content distillation residues. [Pg.250]

Rx mixture separates, H2O often added to facihtate color bodies partially removed into separated spent H2SO4... [Pg.78]

Figure 17.12 Corroded area beneath a tubercle on the external surface. The shiny black corrosion product has been partially removed to reveal the depth of penetration. Figure 17.12 Corroded area beneath a tubercle on the external surface. The shiny black corrosion product has been partially removed to reveal the depth of penetration.
Deep well injection Partial removal from Oil field brines low toxicity, Monitoring difficulty... [Pg.456]

MLVSS Mixed Liquor Volatile Suspended Solids - the volume of organic solids that can evaporate at relatively low temperatures (550 C) from the mixed liquor of an aeration tank. This volatile portion is used as a measure or indication of microorganisms present. Volatile substances can also be partially removed by air stripping. [Pg.619]

Volatile A volatile substance is one that is capable of being evaporated or changed to a vapor at a relatively low temperature. Volatile substances also can be partially removed by air stripping. [Pg.628]

MS As are recirculated. The stripped acid gases are fed to a Claus unit" where elemental sulfur is recovered from hydrogen sulfide. In view of air pollution control regulations, the tail gases leaving the Claus unit, R, should be treated for partial removal of the unconverted hydrogen sulfide. Table 3.10 summarizes the stream data. [Pg.76]

Cortisone. 17a,21-Cyclopentylidenedioxypregn-4-ene-3,ll,20-trione(0.25g) in methanol (5 ml) is refluxed with a few drops of 1 JV hydrochloric acid for 15 min. Partial removal of solvent and dilution with water yields cortisone 0.2 g, 97% mp 217-220°. [Pg.414]

In addition to heavy hydrocarbons and water vapor, natural gas often contains other contaminants that may have to be removed. Carbon dioxide (CO2), hydrogen sulfide (H2S), and other sulfur compounds such as mercaptans are compounds that may require complete or partial removal for acceptance by a gas purchaser. These compounds are known as acid gases. H2S combined with water forms a weak form of sulfuric acid, while CO2 and water forms carbonic acid, thus the term acid gas. ... [Pg.151]

Ti(0-/-Pr)4, i-BuMgCl, THF, rt, 69-97% yield. Methallyl and other substituted allyl ethers are not cleaved, but ester groups are partially removed, as expected. ... [Pg.71]

Oxygen can also be removed from feedwater by thermal de-aeration, or partially removed by skilful design of the feed heating system and blowdown recovery. These processes run without cost to the operator, but save chemicals, and, by reducing the required dose of sulfite into the system, decrease the amount of non-volatile solids added into the boiler. [Pg.477]

Wiping Paint is applied conventionally, then paint is wiped off Paint is either totally removed, remaining only in recessed areas, or is partially removed for special effects such as woodgraining. Standard spray-paint setup with a wipe station following. For low production, wipe can be manual. Very highspeed, automated equipment available. [Pg.539]

Persons who have had a total gastrectomy or subtotal gastric resection (when the cells producing the intrinsic factor are totally or partially removed)... [Pg.437]

What strategy will we adopt for dealing with confidentiality issues Will we use volimteers or partially remove confidentiality from all relationships so that evaluation is made possible ... [Pg.310]

In order to ameliorate the problem of solvolytic degradation, compound 109 was treated with TIPSOTf, to provide silyl ether 113 in 72% yield (Scheme 19). The acetonides were removed with PPTS in warm MeOH to provide a mixture of compounds in which the TBS groups were also partially removed. Exposure of this mixture to HF-pyridine successfully generated filipin III (114), in 39 % overall yield from 113. [Pg.72]

For qualitative extraction, a large amount of food is often used and there is no concern about loss of material. If the final objective is, for example, the production of a carotene standard, it is very useful to first extract the sample with a very polar solvent (e.g., MeOH or EtOH) that will remove water and partially remove the xanthophyUs. The alcohol is discarded and the carotenes are then extracted with a suitable less polar solvent. [Pg.451]

A relatively new arrangement for the study of the interfacial region is achieved by so-called emersed electrodes. This experimental technique developed by Hansen et al. consists of fully or partially removing the electrode from the solution at a constant electrical potential. This ex situ experiment (Fig. 9), usually called an emersion process, makes possible an analysis of an electrode in an ambient atmosphere or an ultrahigh vacuum (UHV). Research using modem surface analysis such as electron spectroscopy for chemical analysis (ESCA), electroreflectance, as well as surface resistance, electrical current, and in particular Volta potential measurements, have shown that the essential features (e.g., the charge on... [Pg.31]

OS 39] ]R 25] ]P 27] A 24 h run of a pilot-scale micro reactor for azo pigment production was performed using a diazo suspension [55], At the end of this period, the pressure loss of the micro reactor increased exponentially. Special means were developed to prevent clogging and unstable operation. By partial removal of the deposits, the pressure loss was brought back to normal. [Pg.465]


See other pages where Partial removal is mentioned: [Pg.4]    [Pg.52]    [Pg.36]    [Pg.502]    [Pg.56]    [Pg.370]    [Pg.292]    [Pg.2104]    [Pg.2359]    [Pg.41]    [Pg.228]    [Pg.293]    [Pg.402]    [Pg.450]    [Pg.123]    [Pg.682]    [Pg.237]    [Pg.68]    [Pg.561]    [Pg.770]    [Pg.36]    [Pg.44]    [Pg.162]    [Pg.170]    [Pg.647]    [Pg.99]   
See also in sourсe #XX -- [ Pg.274 , Pg.277 ]

See also in sourсe #XX -- [ Pg.274 , Pg.277 ]




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