Silver vessels

Solution calorimetry has been the most widely applied type of calorimetry because it needs relatively simple apparatus, and a wide choice of liquid reagents is available. Much of silicate thermochemistry, for example, has been based on the hydrofluoric acid solution calorimeters using platinum or silver vessels and fluorinated gaskets (90, 214). 

Hydrargyrum [mercury]. It is found also in ye place where Silver is melted, standing together by drops on ye roofs. And some say that Hydrargyrum is found by itself in ye mines. But it is kept in glassen, or leaden, or tinnen, or silver vessels, for it eats through all other matter, and makes it run out (18, 56). 

Silvered Vessel (or Waltham Abbey Silvered Vessel) Test. See Vol 1, p XXIV... 

Waltham Abbey Silvered Vessel Test. See Silvered Vessel Test in Vol 1, jp XXIV... 

Determination of Detonation Velocity (71-4) Sensitivity to Impact (Sensibilite/ au choc) (74-5) Sensitivity to Friction (75-6) Sensitivity to Initiation (Sensibilite a 1 amorce) (76) Pressure Measurements by Manometric Bomb, by Crusher Test and by Piezoelectric Manometer (79 97) Density Determination (99-100) Chronographs of Schulze and of Le Boulange (101) Tests for Stability by Methods of Abel, Spica, Vieille at 110°C, German at 135° Bergmann-Junk, Su, Hansen-Grotannelli, Silvered Vessel and Taliani (107-09) Explosion Test (109-10)... 

Loss of Weight Test, Marqueyrol s Test, Meerscheidt-Hullessem Test, Mittasch s Test, Obermiiller s Test, Pavlik s Test, Methyl Violet Test, Silvered Vessel Test, Simon Thomas Test, Spica Test, Sy Test, Taliani Test, Taylor s Test, Tomanari s Test, Vacuum Stability Test, Vieille Test, Warmlagermethode 75° (German Storage Test), Will Test... 

Accdg to Gorst (Ref 71, p 12), Russia started to use Trotil (TNT) for loading shells 1909. Silvered Vessel Test, devised by Sir Robertson for detn of stability of Cordite, was described by F.L. Nathan in JSocChemlnd 28, 443 (1909), and briefly described by Reilly (Ref 28a, p 81) and in Vol 1 of Encycl, p XXIV. It is also known as Waltham Abbey Test ... 

Silvered Vessel Test (Vol 1, p XXIV) Surveillance Tests at 65° 80°(Vol l,p XXIV) Taliani s Test (Vol 1, pp XXIV XXV)... 

CDj) T. Urbanski, Vol 2(1965), pp 22-31 gives methods for determining the Stability of Nitric Esters, which include Abel Heat Test, Litmus Test (Vieille Test), Heat Test at 134.5°C, Silvered Vessel Test, Loss of Weight Test, Will Test, Bergmann Junk Test and Manometric Test... 

In the case of SB, DB and propellants, slow but autocatalytic decomposition of NC and NG takes place even at ambient temperatures. This is retarded by the addition of a stabilizer to these propellants and thus the compatibility and the stability or life of these propellants increases. The silvered vessel test and stabilizer consumption rate are the methods which are generally used to predict safe chemical life of propellants in Europe, USA, India and other countries. The migration of explosive plasticizer (NG) and non-explosive plasticizers ( , DEP) from propellants to inhibitors or vice-versa also affect the ballistics, mechanical properties and life of inhibited propellants. 

In 1818, A. Arfvedson 17 causticized lithium carbonate by means of calcium hydroxide, but the sparing solubility of lithium carbonate causes but a poor yield. L. Troost made the hydroxide by dissolving in water the oxide obtained by the combustion of the metal and C. G. Gmelin decomposed lithium sulphate by an eq. soln. of barium hydroxide. In either case, the soln. should.be evaporated rapidly to dryness in a silver vessel, and then fused. 

These results do not conform to those of the silvered vessel test . This test determines the time necessary to produce pronounced exothermic reaction in a sample of powder heated to a temperature of 80°C. This reaction causes a rise of temperature by 2°C above the ambient temperature. The relatively high temperature (80°C) may account for the different results. It may well be that the exothermic reaction recorded here is a reaction between the acid products of the decomposition of the powder and the basic ingredients of the glass of the vessel at the relatively high temperature. 

Pliny describes a method used by the Egyptians for darkening the surface of silver vessels. The silver is mixed with two thirds of finest Cyprian aes, and a proportion of sulphur equal to that of the silver. This mixture is melted in an earthen vessel well luted with potter s earth. This custom, he adds, has now passed to our triumphal statues, the value of the silver being enhanced by deadening its brilliancy. Silver may also be blackened, he says, by the yolk of a hard-boiled egg, but this color is easily removed by the application of vinegar and chalk. That silver becomes stained by contact with mineral waters and the salty exhalations from them, is doubtless an observation dependent upon the presence of hydrogen sulphide in some spring waters. 

Silvered Vessel test. The so-called Silvered Vessel test is a stability test that consists in determining the period of heating necessary to cause exothermic decomposition of the substance. It is usually limited to determining the stability of smokeless powder and is described in Vol. III. 

Biological and medicinal aspects of silver chemistry are covered in Chapter 62 but a number of features will be outlined here. Silver salts are powerful bacteriocides and it has been known for many years that storing water in silver vessels prevents spoilage. Silver nitrate is highly corrosive and can be applied locally to remove warts or cauterize wounds. In many states in the USA, a 1% AgN03 solution is dropped into the eyes of newborn infants to prevent ophthalmia neonatorum. Silver sulfadiazine has been found effective as a topical application to prevent infections in serious bums victims. 

British Tests. See Physical Tests for Determining Explosive and Other Properties Vol 1 and specifically the following British tests a)Ballistic Pendulum Test, p VII b)Exudation(ot sweating) Tests, p XI c)F7 lest(Figure of Insensitiveness Test) p XII Fragment Gun, p XII d)Friction Sensitivity Tests, p XIII e)Hopkinson s Pressure Bar Test, p XVI and i)Silvered Vessel Test or Waltham Abbey Silver Vessel Test, p XXIV... 

Volume of Gases Evolved an Explosion or Detonation may be either calcd or detd experimentally by exploding material in one of the bombs, such as Bichel Bombfqv), and then collecting and measuring the volume. The volume(in liters) evolved by 1 kg of expl, measured at NTP, is called specific volume or normal vol-umefVo). Refs l)Marshall 2 (1917),443 2)Pascal(1930),15 3)Vennin, Burlot Lecorcbe( 1932) 4)Stettbacher(1933) 69 5)Stett bacher( 1948), 13 6)Stettbacher(1952),16 Waltham Abbey Silvered Vessel Teat. See Silvered Vessel Test... 

Sicherheitszundschnure = safety fuses 276 Silberacetylid 285 Silberazid 286 Silbercarbid 285 Silberfulminat 287 silver acetylide 285 silver azide 286 silver carbide 285 silvered vessel test 286 silver fulminate 287 single bases powders 287 SiNCO = qas qeneratinq propellant (german) 288... 

Methods providing information on the stability of the explosive based on the heat of decomposition evolved during storage (silvered vessel test). 

Frey s variant of the silvered vessel test has been in use in the Germany In its variant, different amounts of heat are supplied to the electric heating elements mounted inside the Dewar flask, and the temperature differences between the interior of the Dewar vessel and the furnace are measured by thermocouples. A calibration curve is plotted from the values thus obtained, and the heat of decomposition of the propellant is read off the curve. In this way, the decomposition temperature at a constant storage temperature can be determined as a function of the storage time, and the heat of decomposition of the propellants can thus be compared with each other. If the measurements are performed at different storage temperatures, the tempera-... 

If the alloy resists the action of aqua regia, fuse it with sodium hydroxide pellets in a silver dish or crucible (CAUTION). When decomposition is complete, allow to cool, transfer the silver vessel to a beaker and extract the melt with water remove the silver vessel from the beaker. Strongly acidify the contents of the beaker with nitric acid, evaporate to dryness on a water bath, and proceed as above. 

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