CAE in der Prozeßleittechnik

CAE in process control engineering. The design and operation of chemical engineering plant involves collaboration of various specialist departments over a long period in an iterative sequence of steps. Any change in data in any of the necessary iterative steps can generate expensive errors. The aim of computer application and computerized development is thus basically to improve the integration of the various applications. Technical data processing, especially the use of CAD/CAE systems, therefore provides a framework for a whole group of measures intended to provide tools for mediumterm automatic handling of data and re-use of partial solutions in memory.     

Thermo-sensitive poly(N-vinylcaprolactam-co-acetoacetoxyethyl methacrylate) microgels: 1—synthesis and characterization

In the present paper, polymeric microgels have been prepared by surfactant-free emulsion co-polymerization of acetoacetoxyethyl methacrylate (AAEM) and N-vinylcaprolactam (VCL) in water with water-soluble azo-initiator 2,2′-azobis(2-methylpropioamidine) dihydrochloride (AMPA). It was found that the particle diameter decreased gradually when higher amounts of AAEM were used in monomer mixture. Obtained microgels possess lower critical solution temperature (LCST) in water solutions, so rapid decrease of the particle size was observed at elevated temperatures. As was found using simultaneous static and dynamic light scattering, microgels undergo soft sphere–hard sphere transition during heating.     

Untersuchungen zum Netzwerkbildungsprozeß bei der Reaktion von Bisphenol A-Diglycidylether mit 4,4′-Diaminodiphenylmethan

The network formation process of bisphenol A-diglycidylether and 4,4′-diaminodiphenylmethane was investigated by measuring the torque, the conductivity and the soluble part of the crosslinking system. The activation energy for the curing process was estimated from gel time. The volume shrinkage during network formation was measured. The influence of N,N-dimethylbenzylamine as accelerator was discussed.     

Element dynamics of oak ecosystems on acid-sulphurous mine soils in the Lusatian lignite mining district (Eastern Germany)

Seepage water chemistry and input–output budgets of major ions are investigated within an oak chronosequence (Quercus petraea Liebl., 3 years; Quercus rubra L., 26 and 37 years) on acid-sulphurous soils of lignite mining. Due to declining intensity of weathering and deep percolation, the leaching rates of Fe, Al, Mn, Mg, Ca, NH₄ and SO₄-S from soil decline drastically within 34 years. Moreover, an enrichment of NH₄-N, NO₃-N, PO₄-P and K can be noticed, resulting from the accumulation of living biomass.     

Fran Bo njakovi and his world of thermodynamic charts—demonstrated for selected processes with humid air

Some examples of technical processes operating with humid air as a working fluid, such as air compression and evaporation cooling, are discussed using the Mollier diagrams for better understanding of their performance. Bo njakovi ’s important contributions towards the development of graphical methods are illustrated.     

Incorporation of oxygen-18 into the oxirane ring ofcis-9,10-epoxyoctadecanoic acid

The synthesis ofcis-9,10-epoxyoctadecanoic acid by tissue slices of wheat plants infected withPuccinia graminis tritici (Wheat stem rust) has been investigated further. Synthetic methylcis-9,10-epoxyoctadecanoate and the same ester isolated from incubation in an atmosphere containing¹⁸O₂, or a medium containing H₂ ¹⁸O, were analyzed by mass spectrometry. These analyses revealed that molecular oxygen was incorporated into the oxirane ring ofcis-9,10-epoxyoctadecanoic acid. Presented in part at the AOCS Meeting, Minneapolis, October 1969.