The [Ln(H20)9](CF3SO3) 3 complexes with Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Yb and Lu form an isomorphous series of hexagonal structures, a= 13.990(6)-13.259(2), c= 7.444(2)-7.751 (1)A, P63/m, Z = 2. Full crystal data have been published [Harrowfield, Kepert, Patrick & White (1983). Aust. J. Chem. 36,[483][484][485][486][487][488][489][490][491][492]. The [Ln(H20)9] 3+ moiety has a tricapped trigonal prism geometry. The consequences of the lanthanoid contraction were determined from structure refinements with X-ray diffraction intensity data measured for a charge density study at 295 K (wR=0.022-0.051). The Nd structure was also refined with neutron diffraction data (wR = 0.042). The lanthanoid contraction for the bonds to the equatorial oxygens is less than it is for the prism oxygens. This is associated with weakening of the hydrogen-bond network for the equatorial water, while that of the prism water is strengthened. This reflects a change in the interaction between the metal and the ligating water molecules resulting from their orientation. At the upper end of the 4fseries, the trigonally oriented water is less strongly bound.

The microwave heating of ceramic materials has been analyzed by solving the equations for grain growth and porosity (Svoboda and Riedel, 1992) during the late stages of sintering, coupled with the heat conduction equation and electric field equations for 1 -D slabs. Microwave power absorption and heating profiles have been calculated for Al,O, and Sic in the absence of sintering, and calculations have been cam'ed out to study the effect of increasing dielectric loss of A1,03 as a function of temperature. A comparison of the densification and grain growth for Al,O, during microwave and conventional sintering indicates that within the ffamework of the present model, there is no difference between the two heating modes during the late stages of sintering.

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We investigate the antibacterial effect of ultrafine nanodiamond particles with an average size of 5 nm against the gram-negative bacteria Escherichia coli (E. coli). UV-visible, Raman spectroscopy, and scanning electron microscopy (SEM) have been employed to elucidate the nature of the interaction. The influence on bacterial growth was monitored by measuring optical densities of E. coli at 600 nm as a function of time in the presence of carboxylated nanodiamond (cND) particles (100 μg/ml ) in highly nutritious liquid Luria-Bertani medium. The SEM images prove that cND particles are attached to the bacterial cell wall surface and some portion of the bacterial cell wall undergoes destruction. Due to the change of the protein structure on the bacterial wall, a small Raman shift in the region of 1400 to 1700 cm⁻¹ was observed when E. coli interacted with cNDs. Raman mapping images show strong evidence of cND attachment at the bacterial cell wall surface. Electrotransformation of E. coli with a fluorescent protein markers experiment demonstrated that the interaction mechanisms are different for E. coli treated with cND particles, E. coli by lysozyme treatment, and E. coli that suffer lysis.