Quality control of wastewater treatment: A new approach

This paper presents a new approach to quality control of wastewater treatment. The first part formulates basic principles of statistical process control (SPC) and Taguchi Method. Then it is shown that the classical SPC technique used in industry, cannot be to applied to wastewater treatment plants without adaptation and that the Taguchi Method is inapplicable in this case. This is followed by an example from literature, which demonstrates the problems of applying the SPC method to wastewater treatment. The third part of the paper presents a case study where the performance of a greywater treatment plant is examined. The performance is analyzed by means of cross-correlation between input and output parameters. A new approach to SPC of wastewater treatment, either “Dynamic SPC” or “linear regression SPC”, is presented, and a permeability coefficient is developed (the ratio of the output and input energies). Both are proposed as monitoring tools for wastewater treatment systems.     

A generalized Schwarz lemma at the boundary

Let be an analytic function mapping the unit disc to itself. We generalize a boundary version of Schwarz's lemma proven by D. Burns and S. Krantz and provide sufficient conditions on the local behavior of near a finite set of boundary points that requires to be a finite Blaschke product. Afterwards, we supply several counterexamples to illustrate that these conditions may also be necessary.

     

Investigations of axisymmetric deformation of geometrically nonlinear,rotationally orthotropic,circular plates

Some results of qualitative investigations and of numerical solutions to the problem of axisymmetrical deformations of circular, geometrically non-linear, rotationally orthotropic plates are presented. The qualitative studies reveal certain general characteristics of behavior and proofs are obtained only on the basis of form, in analogy to the qualitative theory of differential equations. For numerical solutions we employ the shooting method in combination with the ‘deformation map’, which is similar to Poincaré's phase plane.     

Slow rotation in the bimetric theory of gravitation

The equations describing the moment of inertia and the dragging of inertial frames of slowly rotating neutron stars are derived according to Rosen's bimetric theory of gravitation. Numerical calculations of the properties of neutron stars according to the bimetric theory and general relativity were made using several equations of state. The general trend found is that in the bimetric theory neutron stars with a given mass induce a smaller dragging of inertial frames than in general relativity. The moment of inertia of low-mass stars also is smaller in the bimetric theory. For high-mass stars, however, the moment of inertia is found to be larger in the bimetric theory.In partial fulfillment of the requirements for the D.Sc. degree.     

Potato kugel

LetP be a solid, homogeneous, compact, connected “potato” in space which attracts each point outside it (according to Newton’s law) as if all its mass were concentrated at a single point. Answering a question of Lee Rubel, we show thatP is a ball. The same conclusion is also obtained under substantially weakened hypotheses.     

Heat evolution of micelle formation, dependence of enthalpy, and heat capacity on the surfactant chain length and head group

Micelle formation by many surfactants is endothermic at low temperatures but exothermic at high temperatures. In this respect, dissociation of micelles (demicellization) is similar to dissolving hydrocarbons in water. However, a remarkable difference between the two processes is that dissolving hydrocarbons is isocaloric at about 25 degrees C, almost independently of the hydrocarbon chain length, whereas the temperature (T*) at which demicellization of different surfactants is athermal varies over a relatively large range. We have investigated the temperature dependence of the heat of demicellization of three alkylglucosides with hydrocarbon chains of 7, 8, and 9 carbon atoms. At about 25 degrees C, the heat of demicellization of the three studied alkylglucosides varied within a relatively small range (DeltaH=-7.8+/-0.4 kJ/mol). The temperature dependence of DeltaH(demic) indicates that within the studied temperature range the heat capacity of demicellization (DeltaC(P,demic)) is about constant. The value of DeltaC(P,demic) exhibited an apparently linear dependence on the surfactant's chain length (DeltaC(P,demic)/n(CH(2))=47+/-7 kJ/mol K). Our interpretation of these results is that (i) the transfer of the head groups from micelles to water is exothermic and (ii) the temperature dependence of the heat associated with water-hydrocarbon interactions is only slightly affected by the head group. This implies that the deviation of the value of T* from 25 degrees C results from the contribution of the polar head to the overall heat of demicellization. Calorimetric studies of other series of amphiphiles will have to be conducted to test whether the latter conclusion is general.     

An unusual reaction of azide with nitroolefins

The reaction of sodium azide in DMSO with 9-dinitromethylenefluorene (DNF) and 9-bromonitromethylenefluorene (BNF) results in the formation of N-cyano-9-iminofluorene ($\text{2}$). The overall reaction time is two minutes at room temperature.     

The preparation of some cyclic phosphonates and their use in olefin synthesis

The preparation and the use in olefin synthesis of two 5-membered cyclic phosphonates, 2-carbethoxy-methyl 4,5-dimethyle-2-oxo-1,3,2-dioxaphospholane (4b) and 2-cyanomethyl-4,5-dimethyl-2-oxo-1,3,2-diox-aphospholane (4c) and the 6-membered phosphonates, 2-carbalkoxymethyl-5,5-dimethyl-2-oxo-1,3,2-diox-aphosphorinanes (5a and 5b) and 2-cyanomethyl-5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinane (5c) are described. Reactions of 4b with aromatic and aliphatic aldehydes lead to preferential formation of cis-olefins. Reactions of the other cyclic phosphonates with aldehydes lead to various mixtures of cis and trans olefins.     

Intramolecular Vinyl Radical Cyclization Reactions of cyclohexadienes derived from sequential additions to (arene)(tricarbonyl)chromium complexes. Preliminary communication

Cyclohexa-1,3-dienes 7–10 with a 1,5,6-substitution pattern were prepared in a one-pot reaction sequence by sequential addition of MeLi and propargyl bromides to the tricarbonylchromium complex 1a . These products were subjected to radical cyclization procedures. Vinyl radical generation by Bu₃Sn addition to the propargyl group in 7–10 was followed by regio- and diastereoselective intramolecular ring closure. Two different 5-exo-trig cyclizations are possible via different vinyl radical intermediates and cyclization to one or the other of the termini of the cyclohexadiene moiety. Internal alkynes reacted to yield exclusively the cis-fused hexahydroindene products 12–14 , whereas the terminal alkyne yielded bicyclo[3.2.1]octenes 11 as sole products.