Study of the kinetics of catalytic decomposition of hydrazine vapors on palladium

The decomposition rates of N2H4 on a palladium surface are studied. Experiments were conducted in a circulating unit at atmosphere pressure. The experimental method is described. The laws found for the reaction kinetics are explained by equations

Petiole hyponasty: an ethylene-driven, adaptive response to changes in the environment

Hyponastic (upwardly bending) growth by leaves is a response of numerous plant species to adverse environmental conditions. This review summarises current knowledge on hyponasty with a particular focus on the role of ethylene in regulating this phenomenon and its possible adaptive significance

1-substituted cyclopropenes: Effective Blocking Agents for Ethylene Action in Plants

A series of 1-alkane substituted cyclopropenes has been prepared and tested as ethylene antagonists using banana fruits as an assay system. 1-Methyl-, 1-ethyl-, 1-propyl-, 1-butyl-, 1-pentyl-, 1-hexyl-, 1-heptyl-, 1-octyl-, 1-non-yl-, and 1-decylcyclopropene were all very active compounds. 1-Methylcyclopropene protected bananas from ethylene with a minimum concentration of 0.7 nl.l−1 after a 24 h exposure. As the carbon chain length was ex-tended the minimum requirement increased some, but starting with 1-butylcyclopropene, the minimum concen-tration requirement declined and many cyclopropenes were required in lower concentrations than 1-methylcy-clopropene. The time of protection at ambient temperature (22–23 °C) was 12 d for 1-methyl-, 1-ethyl-, 1-propyl-