Damping precautions

Aeration of ferric sulfate should be held to a minimum because of the hygroscopic nature of the material, particularly in damp atmospheres. Mixing of ferric sulfate and quicklime in conveying and dust vent systems should be avoided as caking and excessive heating can result. The presence of ferric sulfate and lime in combination has been known to destroy cloth bags in pneumatic unloading devices. Because ferric sulfate in the presence of moisture will stain, precautions similar to those discussed for ferric chloride should be observed. 

In summer or in places with a warm dry climate, pungent, warm and bitter herbs should not be used at high doses because the pores of the body are not tightly closed and so the body fluid can easily be consumed by heat. This precaution relates to herbs that induce sweating, expel wind and cold, disperse the Lung-Qi, dry dampness and increase urination. 

In winter or in cold places, cold, bitter, sour and astringent herbs should be prescribed in a relatively low dose. This precaution relates to herbs that clear heat, cool blood and drain downward. In humid places, herbs that transform dampness, activate the Qi movement and promote digestion should be used in relatively large doses because the herbs need extra strength to overcome the dampness. 

In dry conditions decorative laminates will shrink, and in damp they will expand unless suitable precautions are taken the associated movements can give rise to stress cracking of laminates and the bowing of composite boards. Since the phenol-formaldehyde resins are more stable in this respect than melamine-formaldehyde, laminates with phenolic kraft cores have dimensional stability better than those with melamine core papers—and thick laminates incorporating many plies of phenolic core paper are more stable than thin laminates with fewer plies. 

The submitters and the checkers prepared the sodium ethoxide in the conventional manner. However, sodium eth-oxide and sodium methoxide are very conveniently prepared by the inverse procedure, as described by Tishler in Fieser, Experiments in Organic Chemistry, 2nd Ed., 1941, D. C. Heath and Company, New York, p. 385 (bottom) The metal is placed in the flask, and the alcohol is added through the condenser at such a rate that rapid refluxing is maintained. It is necessary, as a precautionary measure, to damp the flask and not to trust to the friction between a rubber stopper and the flask to hold the flask in place. When this precaution is taken, a cooling bath may be used with safety. It is necessary to cool the flask the metal must not be allowed to melt, as this will result in the formation of one large mass with a greatly decreased metallic surface. (Private communication, C. F. H. Allen.)... 

I have kept such a mixture several years with no deterioration, however reasonable storage precautions should be observed.All such mixture type powders, including com-mercially prepared black powder, should be protected from dampness. All will deteriorate If exposed to large amounts of humid air, but If you use common sense, they will keep Indefinitely. 

The use of primers is also advisable if the bonded parts are to be subjected to temperature changes, damp conditions, tension compression, shear forces, etc. Some porous substrates and plastic materials also require primers. Primers can be applied to a thoroughly prepared surface by brushing, spraying or dipping to form a thin film. All primers contain flammable solvents and therefore safety precautions are essential. 

Place one wet nitrocellulose membrane on wetted (excess blotted off) 3MM filter paper, place the gel on top and then a second nitrocellulose membrane (cut corners aligned no air bubbles precautions as in A6) and another damp 3MM filter paper. 

A precaution must be taken in using this method (Szoke and Meiboom, 1959) since the wiggle beat decay may be artificially damped also by the receiver coil. This radiation damping is most serious when high packing factors for receiver coils are obtained in commercial spectrometers, as is shown by the formula... 

Whatever may bo the form or nature of the vessels employed, care must be taken not to flU them full, also to cover those which ore to be placed on the sand-bath with a damp piece of parchment tightly tied round the top, with many pin holes pneked in it. If this tatter precaution be neglected, the increased volume produced by the heat and also the expansion of the air may burst it. Moreover, the process is never so well conducted in a vessel that is too Aill. 

Properties Gray powd. m.w. 65.38 m.p. 419.5 C b.p. 907 C Toxicology TCLo (inh., human, 50 min) 124 mg/m primary irritant mutagen avoid inh. of dust TSCA listed Precaution Dangerous fire risk may fomi explosive mixt. with air dangerous when wet when damp, may heat and ignite spontaneously on exposure to air keep away from oxidizers (can ignite)... 

LDLo (IV, mouse) 85 mg/kg poison by IV route causes respiratory tract irritation, eye and skin irritation may cause allergic skin reaction causes Gl irritation with nausea, vomiting and diarrhea questionable carcinogen tumorigen human mutagenic data TSCA listed Precaution Hydrogen gas may be evolved from moist chromic sulfate container may rupture if damp material is sealed for prolonged periods Hazardous Decomp. Prods. Heated to decomp., emits SOx and Cr... 

Synonyms DAMP 1,3-Diaminopentane Empirical C5H14N2 Formula H2NCH2CH2CH(C2Hs)NH2 Properties Liq., si. odor misc. with water m.w. 102 dens. 0.855 g/ml vise. 1.89 cp vapor pressure 1 mm Hg (20 C) b.p. 164 C flash pt. (CC) 59 C surf. tens. 32.2 dyne/cm Precaution Corrosive, flamm. incompat. with strong oxidants... 

Precaution Dangerous fire risk may form explosive mixt. with air dangerous when wet when damp, may heat and ignite spontaneously on exposure to air keep away from oxidizers (can ignite)... 

Know electrical precautions for welding. Insulate yourself from both the work and the metal electrode holder. Don t work while standing on damp surfaces. Check for and report defective equipment. 

Since a single furnace is used for three dryway operations, calcination, hydrogen reduction and hydrofluorination, the transfer of solids is minimized. The initial charging of trays and loading these into the furnace is relatively free from dust hazard since the ammonium di-uranate feed material is damp. Special precautions are needed, however, for removal of the final uranium tetrafluoride product from the trays, since it is a dry dusty powder and tends to adhere to the trays to some extent. This operation is therefore carried out in a small glove box , i.e. in a sealed and vented... 

A passive device, as is the case for dampers, may only absorb energy from the system. That is why the damping force can only act in the opposite direction of its velocity. Hence, if the calculated optimum damping cmistant has a negative sign, the required force will not be producible. In this case, the damping constant will take its minimum value of 5,000 Ns/m. In addition a numerical precaution is taken to prevent a divide by zero error. During the calculation of the optimum damper constant, the smallest absolute damper velocity is limited to 1 mm/s. This does not have a detrimental effect to the structural response, since the worst case causes a force of 25 N only. 

Hard horizontal surfaces should be damp mopped or sponged with a solution of water and household detergent or a lead-specific detergent. [If TSP (trisodium phosphate) or a phosphate-containing automatic dishwashing detergent is used, precautions should be taken, as described in Chapter 3.]... 

If asbestos is present, then special precautions will be required including the provision of overalls and respiratory protection, the need for damping down and the avoidance of breaking asbestos sheets. Safe disposal of waste asbestos is particularly important. 

In confined and conductive locations the potential electric shock hazard is increased and special precautions are needed. Examples of confined, conductive spaces are inside boilers and other metal vessels or inside metal pipes, flues and ducts where the area of body contact to earthed metalwork is likely to be substantial. Even if the interior is dry, the shock risk is enhanced, but if it is damp it is worse. In these circumstances the llOV system is not considered safe and pneumatic, hydraulic or battery powered tools are advocated. For lighting, battery powered cap and hand lamps could be used or the luminaires could be supplied from a safety transformer at not more... 

Precaution—damp the piston cylinder firmly to a steady work surfiice. 

Environmental Biodeg, keep out of sewers, drains, surfaces and underground water considered to be of low toxicity for aquatic life Precaution Wear gloves, goggles, overalls avoid contact with flames Hazardous Decomp. Prods. Can generate adductors of ethylene oxide Storage Store in original, closed container R.T. protect from dampness and heat sources... 

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