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Drawability of ultrahigh molecular weight polyethylene (UHMW-PE) reactor powders, prepared by using a highly active Ziegler type catalyst, has been studied as functions of catalyst activity, polymerization temperature, monomer pressure and sample molecular weight. Compacted powder films of UHMW-PE, prepared in a 1000-fold range of polymerization rates, were drawn by a two-stage technique; i.e. the initial solid-state coextrusion at 110°C followed by tensile drawing at 135°C, some 5°C below the melting point. It was found that an appropriate range of molecular weights (Mv=1.6–3.0×106) existed for achieving a high draw. The UHMW-PE prepared even at a high polymerization rate of 43,600 (g of PE)/(mmol of transition metal,h) could be drawn to draw ratios (DR) over 50, producing tapes with tensile modulus and strength over 100 and 1.0 GPa, respectively. This level of catalyst activity is sufficient for the modern industrial production of UHMW-PE. The reduction of polymerization rate, by lowering monomer pressure and polymerization temperature, produced UHMW-PE with improved ductility. Furthermore, at the same polymerization rate, the ductility of reactor powder was improved more significantly by lowering the former parameter than the latter, reflecting the characteristic effect of each of these polymerization variables on the morphology formation during polymerization. Thus, the reactor powders prepared at 40–60°C and monomer pressure of 1 atm could be drawn to DR's of 100–125. Such highly drawn products exhibited tensile moduli and strength up to 144 and 1.6 GPa, respectively.

Pollen grains of Lilium auratum, Lilium longiflorum, Camellia sasanqua and Impatiens balsamina were soaked in various kinds of organic solvents such as acetone, benzene, petroleum benzine, benzyl alcohol, butanol, ethanol, methanol, isopropanol, diethyl ether, petroleum ether and choroform, and stored at 4–6 C for 24 hr. All pollen grains except in benzyl alcohol showed evidence of viability, and grains which had been stored in acetone, benzene, petroleum benzine, diethyl ether, petroleum ether and chloroform produced longer pollen tubes than grains of fresh pollen, especially Camellia sasanqua, whose pollen grew tubes 3 times as long as those of a control. Lilium auratum pollen grains had retained their viability after 80 days in acetone, benzene, petroleum benzine, diethyl ether and petroleum ether, and generative nuclei in pollen thus stored divided to form 2 sperm nuclei in artificial culture.

The resting egg of brine-shrimp ( Artemia salina ) which had been soaked in various organic solvents such as acetone, acetonitril, benzol, chloroform, ethyl ether, petroleum benzene, pyridine, and xylol for 10 days hatched and grew in artificial sea water in just the same way as did unsoaked eggs.

Volatile constituents of parts of plants inhibited the germination ofCamelia sinensis pollen grains. Growing pollen tubes were affected by a 1-sec treatment with volatile constituents ofAllium, and tubes treated for 4–6 sec swelled abnormally at the tips and stopped growing; the reaction resembled that of pollen irradiated with γ-rays at 200 kR.