Shell silver

Alternate names Argentum, argentum crede Cl 77820, shell silver, silver atom, silvercolloidal, silflake, silpowder, silber Lunar caustic fused silver nitrate, molded silver nitrate argenti, nitras, nitric acid silver (I) salt, nitric acid silver (1+) salt, silver (1+) nitrate... 

SYNS ARGENTUM C.I. 77820 SHELL SILVER SILBER (GERMAN) SILVER ATOM... 

SYNONYMS argentium, shell silver, silver metal... 

SYNONYMS Synonyms vary depending upon the specific soluble silver compound. The synonyms for silver are as follows argentum, shell silver, silver atom, silver metal. 

Shellac gum Shellac orange S-40. See Shellac Shell silver. See Silver... 

Synonyms Argentum Cl 77820 Shell silver Silver atom Silver, colloidal ClasAation Metallic element Empkical Ag... 

Shellmax 405. See M icrocrystal I i ne wax Shell Mineral Spirits 7 EC Shell Mineral Spirits 135. See Mineral spirits Shell Polybutylene 0200 Shell Polybutylene 0300, 0400, 0700 Shell Polybutylene 1600A Shell Polybutylene 4101 Shell Polybutylene 4103 Shell Polybutylene 411 a, Shell Polybutylene 4121, 4127, 4128 Shell Polybutylene 8240, 8640. See Polybutene Shell silver. See Silver Shellsol 9 Shellsol 16. See Naphtha, medium aliphatic... 

Bartlett R J and Silver D M 1975 Many-body perturbation theory applied to eleetron pair eorrelation energies I. Closed-shell first-row diatomie hydrides J. Chem. Rhys. 62 3258-68... 

Fig. 1. Global distribution of seabed mineral deposits, where x represents chromite + barite titanium, zirconium, hafnium, and thorium tin I gold, platinum, and silver 3 sand and gravel shell, calcium carbonate gems marine polymetaUic sulfides phosphorites Cl cobalt cmsts S sulfur and B...

Ethylene oxide (qv) was once produced by the chlorohydrin process, but this process was slowly abandoned starting in 1937 when Union Carbide Corp. developed and commercialized the silver-catalyzed air oxidation of ethylene process patented in 1931 (67). Union Carbide Corp. is stiU. the world s largest ethylene oxide producer, but most other manufacturers Hcense either the Shell or Scientific Design process. Shell has the dominant patent position in ethylene oxide catalysts, which is the result of the development of highly effective methods of silver deposition on alumina (29), and the discovery of the importance of estabUshing precise parts per million levels of the higher alkaU metal elements on the catalyst surface (68). The most recent patents describe the addition of trace amounts of rhenium and various Group (VI) elements (69). 

Ethylene oxide is produced in large, multitubular reactors cooled by pressurized boiling Hquids, eg, kerosene and water. Up to 100 metric tons of catalyst may be used in a plant. Typical feed stream contains about 30% ethylene, 7—9% oxygen, 5—7% carbon dioxide the balance is diluent plus 2—5 ppmw of a halogenated moderator. Typical reactor temperatures are in the range 230—300°C. Most producers use newer versions of the Shell cesium-promoted silver on alumina catalyst developed in the mid-1970s. 

Group 3 Nitrate/metal compositions without sulphur Compositions with <35-65% chlorate Compositions with black powder Lead oxide/silicon with >60% lead oxides Perchlorate/metal Burn fast Large firework shells Fuse protected signal flares Pressed report cartridges in primary packagings Quickmatches in transport packagings Waterfalls Silver wheels Volcanoes Black powder delays Burn very violently with single-item explosions... 

Cations with completely filled d sub-shells. Typical of this group are copper(I), silver(I) and gold(I) which exhibit Class B acceptor properties. These ions have high polarising power and the bonds formed in their complexes have appreciable covalent character. 

The stability of gold(III) compared with silver(III) has been ascribed to relativistic effects causing destabilization of the 5d shell, where the electrons are less tightly held. Hartree-Fock calculations on AuX4 (X = F, Cl, Br) indicate that relativistic effects make a difference of 100-200 kJ mol-1 in favour of the stability of AuXJ (Table 4.12) [110]. 

Bimetallic nanoparticles, either as alloys or as core-shell structures, exhibit unique electronic, optical and catalytic properties compared to pure metallic nanopartides [24]. Cu-Ag alloy nanoparticles were obtained through the simultaneous reduction of copper and silver ions again in aqueous starch matrix. The optical properties of these alloy nanopartides vary with their composition, which is seen from the digital photographs in Fig. 8. The formation of alloy was confirmed by single SP maxima which varied depending on the composition of the alloy. 

For instance, nanoparticles of silver chloride have been synthesized by mixing two mi-croemnlsions, one containing silver ions and the other containing chloride ions. It was shown that the average particle size, the polydispersity and the number of particles formed depend on the intermicellar exchange rate and/or the rigidity of the surfactant shell [228],... 

Very recently, Williams, Billington Pearson (1992) have examined the effect of reinforcement by silver or silver-tin alloy on the mechanical properties of three glass-ionomer cements. Measurements of compressive, flexural, tensile (measured by the diametral compressive procedure) and shell strength are given in Table 5.17. These results show that the effect of reinforcement varies from cement to cement but, in general, increases it. 

GP 2] [R 3a] A Shell Series catalyst was measured in a fixed-bed configuration and deposited in micro channels electrophoretically (20 vol.-% ethylene, 80 vol.-% oxygen 0.3 MPa 230 °C) [101]. The selectivity was lower in the micro channels (51%) than in the fixed bed (57%) at a conversion of 17%. In a further investigation, a sputtered silver catalyst (cesium promoted) was better than both systems (68%) at higher conversion (25%). 

GP 4] [R 5] For an undisclosed methanol derivative, a selectivity of 96% at 55% conversion was foimd for the micro reactor with silver as construction material (390 °C), which exceeds the performance of laboratory pan-like (40% 50% 550 °C) and short shell-and-tube (85% 50% 450 °C) reactors (Figure 3.37) using elemental silver [1, 49-51,108], At slightly higher conversion, selectivity of the chemical micro processing decreases, and 89% selectivity at 59% conversion is found. 

Doll, K, Pyykkd, P. and Stoll, H. (1998) Closed-shell interaction in silver and gold... 

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