Silver impregnation

Figure 18.1 Typical tangle (T) and plaque (P) as visualised by silver impregnation in the cerebral cortex of a case of Alzheimer s disease. The extracellular plaque (10-50 pm diameter) consists of a central core of amyloid surrounded by glial processes and a number of neurites in a ring formation. The intracellular cytoplasmic tangle is composed of helical filaments in a paired format. (Reproduced with permission of Academic Press from Wischik and Crowther 1986)...

Fig. 4.4(b) N. terminalisNomeronasal septal innervation in human embryo (45 mm), silver impregnation x 13 (from Pearson, 1941). 

Golgi, in early neuroanatomical studies (1898) staining neurones by silver impregnation, observed a reticular apparatus which was crescent shaped and appeared to be linked through canaliculi. The structure was also seen in secretory cells. Between 1949 and 1954, Baker reported the presence of similar systems in unfixed cells examined by phase contrast. The structures could be stained by osmium tetroxide and probably contained lipid. They also stained for glycoprotein and alkaline phosphatase. Baker s confirmation of the existence of the... 

Yamaguchi, T., Baertsch, C., Koval, C.A., Noble, R.D. and Bowman, C.N. (1996) Olefin separation using silver impregnated ion-exchange membranes and silver... 

Silver-impregnated solids may also serve as catalysts in [4+2] cycloadditions. Thus, Mayoral reported that silver ion-exchanged montmorillite K10 functioned as a catalyst for the reaction of methyl 2-cyanocinnamate and cyclopentadiene 185 (Scheme 2.49). The use of such heterogeneous catalysts may enhance catalyst recovery, an important consideration for industrial applications. 

Fink RP, Heimer L (1967) Two methods for selective silver impregnation of degenerating axons and their synaptic endings in the central nervous system. Brain Res 4 369-374. 

Nauta WJH, Gygax PA (1951) Silver impregnation of degenerating axon terminals in the central nervous system (1) Technic. (2) Chemical notes. Stain Technol 263-9. 

The surface of the silica may be dynamically coated with transition metals, and the selectivities observed can be attributed to the complexes between the metal ions and the analyte species [56], The use of silver-impregnated silica (adsorption of salts of transition metals on the silica surface) has been used for the analysis of saturated and unsaturated fatty acid methyl esters (FAME) and triacylglycerols (TAG) [57], The retention of the unsaturated FAME and TAG can be attributed to the stability of the complex that is formed between the K electrons of the carbon-carbon double bonds and the silver ions. The predominant interaction for saturated analytes is with the polar silanol groups. The secondary interactions are those of the silver ions with the unpaired electrons of the carbonyl oxygens of the analytes. The amount of silver adsorbed onto the silica and the pH (employment of acidic or basic modifiers) have been determined to have an effect on the retention and resolution of certain acidic and basic compounds and fatty acids [58]. 

This study is on the development of high-purity isobutane production from isobutane-enriched stream by gaseous adsorption technology. Isobutane purification from Ci mixture, in which not only isobutane, but also n-butane and several kinds of Ct olefins in small or in trace are involved, is very difficult by a traditional distillation method because of their close relative volatilities between constituting components. The continuous layered 3-bed process in which was comprised of six steps as follows pressurization-1 by the cocurrent effluent gas from the other bed, pressurization-2 by isobutane (noduct, adsorption, cocurrent depressurization, countercurrent blowdown, and low pressure purge by isobutane product, was applied. From the experiment, isobutane product with over 99.9% purity and with the trace levels of olefin components could be obtained at ambient temperature. Silver impregnated cliq prefers to CMS for the removal of Ci olefins... 

Adsorbed amount of 1 -butene at 80°C is four times larger than n-butane on modified clay by silver impregnation (Figure 3-(c)). Such a high selectivity of 1-butene over n-butane is mainly due to the presence of Ag ions for 7 complexation. Adsorption amounts of other C4 paraffins and olefins are inferred to be almost the same with that of n-butane and 1-butene, respectively. Uptakes of n-butane and 1-butene on modified clay are surely faster than the corresponding components on CMS. But isobutane component can be considerably adsorbed on modified clay. 

From the process experiment, isobutane product with over 99.9% purity can be continuously obtained with the trace levels of olefin components. Silver impregnated clay prefers to CMS in viewpoint of product purity and productivity. 

The off-gas passes scrubber containing NaOH solution and filters with silver-impregnated zeolite or charcoal in which Ru and I are retained. Kr may be separated by condensation or adsorption on charcoal at liquid-nitrogen temperature. 

Activated carbon, silver-impregnated filters have also been described [78, 79] and have been shown to be effective in preventing growth of, or killing, Ps. fluorescens and Ps. aeruginosa in water supplies. 

Fig. 24.11 Syphilis, secondary stage hepatitis syphilitica. In the liver parenchyma, massive amounts of corkscrew-shaped syphilis pathogens, 6-10 jm in length, are visible (= treponema palhdmn) (silver impregnation)...

Nodular regenerative hyperplasia of the liver has been reported in three patients with inflammatory bowel disease who had taken tioguanine for more than a year and who had raised serum liver enzymes all three had histological foci of nodular regenerative hyperplasia, which was best seen with reticulin silver impregnation (4). 

A,S.ergotamine,ergo tami nine,caffeine Butalbital.phenobarbital Separation on silver impregnated silica gel Lichrosorb Si 100 5iim,imp. with 1.09% Agl... 

Ergta.Ergtaine Butalbital, atropine,scopo- phenobarbital lamine,caffeine Separation on silver impregnated silica gel... 

One example is known in which the elements of a phosphinic acid are eliminated in the same reaction step. In the synthesis of (-f)-( / ,2/ )-[( )-hex-l-enyl]-2-vinylcyclopropane [(-E)-dic-tyopterene, 4] and its (—)-enantiomer, the ji-oxo phosphane oxide 2 obtained by condensation of pentyidiphenylphosphane oxide with methyl 2-vinylcyclopropanecarboxylate (1) was first reduced to the corresponding /(-hydroxy phosphane oxide 3 and then treated with sodium hydride in dimethylformamide. This procedure gave the desired diene 4 and its enantiomer in 19 to 23% yield from the P-oxo phosphane oxide. The stereoselectivity was fairly good, giving 85% of the 5-isomer, which could be separated on silver-impregnated silica gel. ... 

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