Flow microcalorimetry in monitoring biological activity of aerobic and anaerobic wastewater-treatment processes

A flow microcalorimetric system which is compatible with the experimental conditions of industrial processes was used to monitor the biological activity of wastewater-treatment systems. Two industrial wastewater-treatment processes were investigated: an activated-sludge (aerobic) treatment of a textile factory effluent and a methane fermentation (anaerobic) treatment of effluents from a cheese factory. In both types of system, the heat flux resulting from metabolic reactions during bacterial degradation of organic substances in the effluent could be measured adequately. Depending on the measurements selected, the calorimetric data could be used to monitor the bacterial activity in the bioprocess, or the effluent degradability or toxicity, or the overall content of degradable substrates in the effluent (loading). The non-invasive measurement of heat flux enabled continuous or semi-continuous on-line monitoring of these biological processes. The response time of the flow calorimetric unit is of the order of minutes, thus yielding process data with minimal delay. These data enable rapid intervention to optimize process parameters (e.g., to control the inlet flow rate or dilution, divert or dilute toxic contaminants, etc.).     

Effects of electronic delocalization on intramolecular proton transfer

The effects of molecular size, conjugation length, and competition with excimer formation on excited state intramolecular proton transfer (ESIPT) in conjugated polymers, in which the intramolecularly hydrogen-bonded moieties reside in the main chain, were examined. A large extent of π-electron delocalization is found to inhibit the ESIPT process. Excimer formation is found to be competitive with ESIPT in the polymers studied, whereas molecular size does not inhibit ESIPT.     

Incorporating expertise into decision analysis based DSS

Artificial Intelligence/Expert Systems (AI/ES) techniques are proposed as means of combining the expertise of the experienced decision analyst with the computational methods of Decision Analysis (DA) to provide a user-friendly problem structuring, solution and querying environment which can be accessed directly by those responsible for managerial decisions.Such a system can be implemented as an Expert System shell. The key features of the shell are the inclusion of knowledge from previous problems through problem templates and the use of a combination of natural language and influence diagrams to communicate with users.This shell has the potential to further expand the use of DA by helping to overcome the DA skill shortage and to address some of the difficulties associated with purely AI/ES approaches to complex business problem solving. The greatest benefit of an Expert Decision Analyst is through integration with organisational DSS to support valuable information processing activities such as strategic decision-making.     

Relaxational processes and instability in lasers

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 48, No. 2, pp. 219–224, February, 1988.     

1H NMR spectral parameters and configurational assignment of the isomeric 1,4-diacetoxy-2- t-butyl-3-methylcyclopentanes

The isomeric 1,4-diacetoxy-2-t-butyl-3-methylcyclopentanes have been prepared starting from 2-t-butyl-3-methyl-4-hydroxy-2-cyclopentenone and 3-t-butyl-2-methyl-4-hydroxy-2-cyclopentenone. Configurational assignments are made on the basis of ¹H NMR data.     

COPPER QUENCHING OF THE VARIABLE FLUORESCENCE IN Dunaliella tertiolecta. NEW EVIDENCE FOR A COPPER INHIBITION EFFECT ON PSII PHOTOCHEMISTRY

Abstract— The copper quenching effect on fluorescence in Dunaliella tertiolecta was studied. 30% of variable fluorescence was quenched in the presence of 70 μ,M CuS0₄. We confirmed that the copper inhibitory effect on photosystem II (PSII) activity is located on its oxidizing side. Further, we indicate that the complementary area is decreased by copper. Since the quantum yield of PSII photochemistry was lowered and the rate of PSII primary electron acceptor Q_A remained unaffected, we can conclude that some PSII reaction centers were inactivated by copper.     

Light scattering by dense dielectric media

Light scattering in the dipole approximation is related form first principles to a macro-polarizability operator in which intermolecular force correction to the individual-molecule polarizabilities are included. As an example, the Kirkwood-Hellwarth local-field correction is derived.