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Polyacetylene, which consists entirely of conjugated double bonds, exhibits a number of interesting features with regard to optical, electronic, or magnetic properties such as a nonlinear optical effect,1 electrical conductivity,2 or ferromagnetism.3 Especially, synthesis of polyacetylene films with few sp2 defects has been the subject of many efforts to prepare organic polymer films of high electrical conductivity.4This paper reports that a monolayer of polyacetylene type can be prepared from (19-(trimethylsilyl)-18nonadecynyl)trichlorosilane ((CH3)3SiC=C(CH2)i7Si-CI3: SA-NTS) adsorbed monomolecularly on a silicon substrate by a chemical adsorption (CA) technique developed by Sagiv5-9 followed by polymerization initiated either by (1) catalysts or by (2) high-energy electron beam (EB) irradiation.SA-NTS was selected as film substance in this study, because the polymerization process of (silylmethyl)acetylene derivatives was studied in detail.10-13Synthesized SA-NTS was characterized by NMR, IR, and mass spectrometry. The purity of the compound was determined to be 94.4% by gas chromatography. The method of synthesis will be published elsewhere. The substrate on which the SA-NTS monolayer was deposited was a Si wafer covered with SI02/A1 prior to use for the measurement of IR spectra or a quartz plate for the UV spectra. Other chemicals used, unless otherwise noted, were obtained from Aldrich Chemicals Co., in pure grade, and used without further purification.

Systems Analysis for the Control of Toxics. S. K. Friedlander wishes to express his appreciation for a senior Humboldt award from the German government during the course of this research. Nomenclature A0 preexponential factor, gg/(s-m1 2'Torr) dp diameter of elementary soot spheroids, nm dp0 initial diameter of soot spheroids, 20 nm £a activation energy, kcal/mol k surface reaction rate constant, #ig/(s-m2) kB Boltzmann constant, 1.38 X 10"18 erg/mol m mass of an oxygen molecule, 5.31 X 10"23 g M soot loading per cross sectional area of the filter, jitg/cm2 Mcat catalyst loading per filter cross sectional area, mg/cm2 MWc molecular weight of carbon, 12 g/mol N number of soot spheroids in filter/cm2 iVAv Avogadro number, 6.023 X 1023 mol"1 Pq2 partial pressure of oxygen, Torr t time, s if total reaction time, s T temperature, K p density of the elementary soot spheroid, 2 g/cm3