Cobalt handling

The ACGIH adopted TLV/TWA for 1992—1993 for fluorides as F is TWA 2.5 mg/m, and for cobalt as Co metal dust TWA 0.05 mg/m. Dust masks should be used while handling both the cobalt fluorides and all other cobalt compounds. CoF is shipped as an oxidizer and a corrosive material. 

Inhalation of extremely fine carbide, cobalt, and nickel powders should be avoided. Efficient exhaust devices, dust filters, and protective masks are essential when handling these powders. 

To achieve the synthesis of all the chlorophylls as magnesium chelates we shall return later to the way the magnesium was inserted while simultaneously the metals iron, cobalt and nickel were prevented from entering the chlorin centre despite the facts that all these metals bind more strongly to chlorin, and they themselves have to be handled specifically and separately to make coenzymes based on them. We note first the general advantages of metal insertion and once again observe the sophistication of the... 

Handl, J. and A. Pfau. 1989. Long-term transfer of 1-129 into the food chain. Sci. Total Environ. 85 245-252. Handl, J., A. Pfau, and F.W. Huth. 1990. Measurements of 129I into the food chain. Health Phys. 58 609-618. Hanson, L.H. 1990. Sterilizing effects of cobalt-60 and cesium-137 radiation on male sea lampreys. North Amer. Jour. Fish. Manage. 10 352-361. 

As reported previously, preparation and handling of highly purified [Go2(GO)8] required tiresome and careful operations because it ignites spontaneously upon contact with air. Some modified ways to use stable cobalt precursors appeared in the literature. Early attempts of Billington to use ethyne-[Go2(GO)6] and recent examples using 17 and 18 are representative examples in this category (Figure 2). ... 

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