This paper theoretically analyzes the combined effect of slip velocity and surface roughness on the performance of Jenkins model based ferrofluid squeeze film in curved annular plates. The effect of slip velocity has been studied resorting to the slip model of Beavers and Joseph. The stochastically averaging method of Christensen and Tonders has been deployed for studying the effect of surface roughness. The pressure distribution is derived by solving the associated stochastically averaged Reynolds type equation with suitable boundary conditions, leading to the computation of load carrying capacity. The graphical representations reveal that the transverse surface roughness adversely affects the bearing performance. However, Jenkins model based ferrofluid lubrication offers some scopes in minimizing this adverse effect when the slip parameter is kept at minimum. Of course, an appropriate choice of curvature parameters adds to this positive effect in the case of negatively skewed roughness. Moreover, it is established that this type of bearing system supports certain amount of load; even when there is no flow which does not happen in the case of conventional lubricant based bearing system.

Resin samples have been prepared by the Friedel-Crafts polymerization of methylanisole with 1 ,Zdichloro ethane. The samples were characterized by IR-spectra and number average molecular weights R, by vapour pressure osmometry (VPO). The thermal characterization has been carried out by differential thermal analysis (DTA), thermogravimetry (TG) and differential scanning calorimetry (DSC). Kinetic parameters for the decomposition are determined from TG-and DTA-studies. Thermal stability is found to be dependent upon the position of the methyl group on the aromatic nucleus. ZUSAMMENFASSUNG : Durch Friedel-Crafts-Polymerisation von Methylanisol mit I ,2-Dichlorethan wurden Harze hergestellt. Sie wurden durch IR-Spektren und mittlere Molekulargewichte (Rn) aus dampfdruckosmometrischen Messungen charakterisiert. Das thermische Verhalten wurde mit Differentialthermoanalyse (DTA), Thermogravimetrie (TG) und Differential-Scanning-Kalorimetrie (DSC) untersucht. Kinetische Parameter fur denAbbau wurden aus TG-und DTA-Untersuchungen bestimmt. Es wurde gefunden, da8 die thermische Stabilitat von der Position der Methylgruppe am aromatischen Kern abhangt.

Resins based on condensation of o‐hydroxyacetophenone with 1.2‐dichloroethane in presence of anhydrous aluminum chloride were prepared. The nature and properties such as spectral, molecular weight by vapour pressure osmometry, conductometric titration and thermal behavior of these resins were studied.

Polymeric metal complexes of 3,3'-benzidine dicarboxylic acid with bivalent metal ions such as copper, nickel, cobalt, zinc and manganese have been synthesized and their properties, composition, IR-absorption spectra and magnetic susceptibilities were investigated. The coloured, powderly solids were obtained by refluxing the metal acetate and the ligand in the appropriate ratio for about half an hour and dried at 110 "C. The compounds are stable and insoluble in common solvents.The analytical data indicate the general formula, [ML]. for Cu(II), Mn(I1) and [M4LS]. for Ni(II), Co(I1) and Zn(I1). The mode ofcoordination ofthe ligand with metal ions has been elucidated by comparing IR spectra of the ligand and the complexes. A polymeric structure is proposed for the complexes. ZUSAMMENFASSUNG:Polymere Metallkomplexe aus 3,3'-Benzidindicarbonsaure und den bivalenten Metallionen Kupfer, Nickel, Kobalt, Zink und Mangan wurden synthetisiert; ihre Eigenschaften, Zusammensetzung, IR-Spektren und magnetische Suszeptibilitat wurden untersucht. Die gefarbten, pulvrigen Feststoffe wurden erhalten, indem die Metallacetate und der Ligand im geeigneten Verhaltnis ca. 1/2 h am RuckfluB erhitzt und dann bei 110 "C getrocknet wurden. Die Produkte sind stabil und in normalen Losungsmitteln unloslich.Die analytischen Daten zeigen die allgemeine Formel [ML]. fur Cu(I1) und Mn(I1) an, dagegen die Formel [M4L5]. fur Ni(II), Co(I1) und Zn(I1). Die Art der Koordination des Liganden mit den Metallionen wurde ermittelt durch Vergleich von IR-Spektren des Liganden und des Komplexes. Es wird eine polymere Struktur vorgeschlagen.

Resins were prepared by Friedel-Craft polymerization of chloroanisoles and 1,2-dichloroethane. The kinetic parameters were evaluated by the methods of Chatterjee, Freeman-Anderson, Broido, Flynn and Wall, Reich, and Kissinger from the TG and DTA thermograms, respectively. The energy of activation, EA decreased with increasing heating rates. This was explained on the basis of flexible nature and rearrangement of molecules. ZUSAMMENFASSUNG:Durch Friedel-Craft-Polymerisation wurden Harze aus Chloranisolen und 1,2-Dichlorethan hergestellt. Nach den Methoden von Chatterjee, Freeman-Anderson, Broido, Flynn und Wall, Reich und Kissinger wurden aus TG-und DTA-Thermogrammen die kinetischen Parameter bestimmt. Die Aktivierungsenergie EA wurde mit steigender Heizrate geringer, was auf der Basis der Flexibilitat und der Umgruppierung der Molekiile erklart wird. 4 cd ! 2 "' 9, 76 cd A 2. cd A = cd A '9,