Reference

The sensitivity of poplar leaves to lead nitrate and the intracellular localization of lead

The sensitivity of poplar leaves to lead nitrate and the intracellular localization of lead. Ksiazek, M.; Wozny, A.; Siwecki, R. (Inst. Biol., Univ. Poznan, Poznan 61-713, Pol.). Eur. J. For. Pathol., 14(2), 113-22 (English) 1984. CODEN: EJFPA9. ISSN: 0300-1237. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) After 24- and 48-h incubation of detached leaves of 4 poplar species in a Pb(NO3)2 [10099-74-8] soln., morphol. changes were found mainly in the vascular elements. Populus maximowiczii Was the most sensitive of the 4 investigated species. Most resistant to Pb influence were leaves of P. nigra, in which traces indicating the presence of Pb were limited to the veins. One of the symptoms of toxicity to Pb compds. was necrosis, which was also most strongly marked in the case of leaves of P. maximowiczii. Comparison of the anatomical structure of the leaf laminae of the studied poplars also showed differences in mesophyll coherence. This may have been 1 of the reasons for the different reaction of leaves to Pb. The electron microscope showed that Pb accumulated mostly in very small quantities in the vascular bundles. Pb deposits were found in all elements of the bundle: the cells of xylem, phloem, and cambium and in the cells of the sclerenchymatic sheath. Pb deposits, located mostly inside the cell lumen of vessels in the region of bordered pits and in the bordered pits themselves, indicate that Pb was probably transported together with the water stream. However, Pb deposits visible in intracellular spaces and in the middle lamella of xylem cells give good reasons for the assumption that apoplastic transport may also have taken place.

Solution for electroless chromium alloy plating

Solution for electroless chromium alloy plating. Cedarleaf, Curtis E. (USA ). U.S. US 4028116 7 Jun 1977,3 pp. (English). (United States of America). CODEN: USXXAM. CLASS: IC: C23C003-02. NCL: 106001000. APPLICATION: US 72-311437 1 Dec 1972. DOCUMENT TYPE: Patent CA Section: 56 (Nonferrous Metals and Alloys) An aq. coating bath is used for electroless deposition of Cr on treated surfaces. The soln. contains Cr as an org. Cr compd. such as Cr(C2H3O2)3 in relatively high concn., Ni compd. such as Ni(C2H3O2)2 in low concn. only sufficient to render the deposit catalytic, reducing agent, and buffering compds. Thus, a stainless steel [12597-68-1] mold for rubber was coated with a soln. contg. Cr(C2H3O2)3 [1066-30-4] 25, Ni(C2H3O2)2 [373-02-4] 4, NaOAc [127-09-3] 25, HOCH2CO2Na [2836-32-0] 40, NaH2PO2 [7681-53-0] 25, K2C2O4 [583-52-8] 5, and Cu(C2H3O2)2 [142-71-2] 0.1 g/L, and Pb(NO3)2 [10099-74-8] 3 ppm at 208.degree.F. The deposit contained 10-30 Cr, 10-15% phosphide, traces of Cu and Pb, and balance Ni. The mold resisted corrosion staining for 1 month and had no erosion failure in 5 months.