By partial extraction

This paper documents a soil and till survey of the Shiko Lake porphyry copper-gold mineral occurrence near Quesnel Lake, British Columbia, and the comparison of Cu, Au, and other elements by partial extraction geochemical analysis with the distribution of gold and other heavy mineral grains (Lett Doyle 2009). 

T,he original report by Barrer and Makki (1) that aluminum in a high A silica zeolite, clinoptilolite, could be extracted with mineral acid to give a silica pseudomorph, has given rise to considerable research on acid-extracted mordenite (2-6). Hydrogen mordenite is useful as an adsorbent and a catalyst, and its properties for some purposes are improved by partial extraction of the aluminum. Further, the ability to vary aluminum content while maintaining crystallinity offers the opportunity to leam more about the nature of the active sites in mordenite. 

Highly water soluble drugs, as they are typical for oral administration, can be released from polymer beads with low (< 10%) water- but high ethanolswelling capacity at controlled rates, for up to 8 hours. The release of oxprenolol-HCl (77% water solubility) and diclofenac Na (2.6% water solubility) from drug loaded monoliths is a function of water content and crosslink density. By partial extraction of the drug loaded beads the release can be further slowed down and, in the case of oxprenolol-HCl, delayed for several hours the delay is dependent on water content of the polymer and is the result of the formation of a hydrophobic surface membrane. 

Release from Non-Monoliths Obtained by Partial Extraction... 

Hydrolysis of benzanilide. Place 5 g. of benzanilide and 50 ml. of 70 per cent, sulphuric acid in a small flask fitted with a reflux condenser, and boU gently for 30 minutes. Some of the benzoio acid will vapourise in the steam and solidify in the condenser. Pour 60 ml. of hot water down the condenser this will dislodge and partially dissolve the benzoic acid. Cool the flask in ice water filter off the benzoic acid (anifine sulphate does not separate at this dilution), wash well with water, drain, dry upon filter paper, and identify by m.p. (121°) and other tests. Render the filtrate alkaline by cautiously adding 10 per cent, sodium hydroxide solution, cool and isolate the aniline by ether extraction. Recover the ether and test the residue for anifine (Section IV,100). 

Other purification procedures include the formation of the picrate, prepared in benzene soln and crystd to constant melting point, then decomposed with warm 10% NaOH and extracted into ether the extract was washed with water, and distd under reduced pressure. The oxalate has also been used. The base has been fractionally crystd by partial freezing and also from aq 80% EtOH then from absolute EtOH. It has been distd from zinc dust, under nitrogen. 

It has been demonstrated that a solvent-extraction procedure with N-methyl pyrrolidone is capable of producing coal-derived extract pitches with low-ash contents. Moreover, the properties of the pitches can be varied by partial hydrogenation of the coal prior to extraction. The yield of the pitches along with the physical and chemical properties of the cokes and graphites vai in an understandable fashion. 

As noted above, the roasting of most metal sulfides yields either the oxide or sulfate. However, a few metals can be obtained directly by oxidation of their sulfides, and these all have the characteristic property that their oxides are much less stable than SO2. Examples are Cu, Ag, Hg and the platinum metals. In addition, metallic Pb can be extracted by partial oxidation of galena to form a sulfate (the Scotch hearth or Newnham process, p. 370). The oversimplified reaction is ... 

Partially extracted Raney cobalt is very active, but it is easily poisoned by sulfur and tends to lay down carbon more readily than Raney nickel (21). Cobalt is less active than nickel and much less selective to methane... 

In general, a decrease in enantioselectivity was observed after the second reuse. The origin of this effect lies in the partial extraction of the chiral hgand in the hexane phase after each reaction. This was demonstrated by adding a small amount of ligand after the fourth reuse. In all cases, the original enantioselectivity was fully recovered (entries 2 and 3 in Table 6). 

The PemB cellular localisation was determined both in E. chrysanthenu and in an E. coli recombinant strain by Western blot of the cell fractions with a PemB-antiserum. No PemB was detected in the culture supernatant and only trace amounts were found in the soluble cell fractions - periplasm and cytoplasm (Figure 2). PemB was found mostly in the total membrane fraction from which it could be completely extracted by Triton X-100/Mg2+ and partially extracted by Sarkosyl (Figure 2). This behaviour is typical of inner membrane proteins, but since some exceptions have been noticed it does not positively indicate the PemB localisation (15). We performed cell membrane fractionation in sucrose density gradient centrifugation both by sedimentation and flotation, using several markers of inner and outer membrane vesicles. PemB was found in the outer membrane vesicles (data not shown). 

Aluminum-deficient Y zeolites prepared by partial removal of aluminum with a chelating agent (e.g. EDTA) also show improved thermal and hydrothermal stability compared to the parent zeolite. The optimum stability was found in the range of 25 to 50 percent of framework A1 extraction (8). However, the maximum degree of dealumination is also affected by the SiO /Al O ratio in the parent zeolite a higher ratio appears to allow more advanced dealumination without loss of crystallinity (8,25,45). Above 50 or 60 percent dealumination, significant loss of crystallinity was observed. Calcination of the aluminum-deficient zeolite resulted in a material with a smaller unit cell size and lower ion-exchange capacity compared to the parent zeolite. 

The oxidation and the partial oxidation method, the CO2 from an ammonia plant in a reaction with methane, and water all produce different ratios of CO and H2. In addition, CO2 can be removed by solvent extraction. So, the trick is to use two or three of these processes to get the C0 H2 ratio to about 1 2. 

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