Oven exposure testing is a standard benchmark that Li-ion cells must pass in order to be approved for sale by regulating bodies. In order to test the safety of new cell designs or electrode materials, manufacturers must make small test batches of cells. This can be both costly and time consuming. Using reaction kinetics that have been developed for electrode materials with electrolyte exposed to high temperature, and thermal properties of cells from the literature, a predictive model for oven exposure testing has been developed. The model predictions are compared to oven exposure test results for E-One/Moli Energy, Canada, 18650 LiCoO2 /graphite cells and shown to be in good agreement. The model can predict the response of new cell sizes and electrode materials to oven exposure testing without actually producing any cells. This is illustrated with a number of examples: (i) increasing the specific surface area of the graphite electrode; (ii) using LiMn2O4 or other cathode substitutes instead of LiCoO2 ; (iii) varying the diameter of cylindrical cells; and (iv) varying the thickness of prismatic cells. © 2001 The Electrochemical Society. All rights reserved.

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An efficient water soluble fluorescent Al(3+) receptor, 1-[[(2-furanylmethyl)imino]methyl]-2-naphthol (1-H) was synthesized and characterized by physico-chemical and spectroscopic tools along with single crystal X-ray crystallography. High selectivity and affinity of 1-H towards Al(3+) in HEPES buffer (DMSO/water: 1/100) of pH 7.4 at 25 °C showed it to be suitable for detection of intracellular Al(3+) by fluorescence microscopy. Metal ions, viz. alkali (Na(+), K(+)), alkaline earth (Mg(2+), Ca(2+)), and transition-metal ions (Ni(2+), Zn(2+), Cd(2+), Co(2+), Cu(2+), Fe(3+), Cr(3+/6+), Hg(2+)) and Pb(2+), Ag(+) did not interfere. The lowest detection limit for Al(3+) was calculated to be 6.03 × 10(-7) M in 100 mM HEPES buffer (DMSO/water: 1/100). Theoretical calculations have also been included in support of the configuration of the probe-aluminium complex.

A newly designed probe, 6-thiophen-2-yl-5,6-dihydrobenzo[4,5]imidazo-[1,2-c] quinazoline (HL(1)) behaves as a highly selective ratiometric fluorescent sensor for Fe(2+) at pH 4.0-5.0 and Fe(3+) at pH 6.5-8.0 in acetonitrile-HEPES buffer (1/4) (v/v) medium. A decrease in fluorescence at 412 nm and increase in fluorescence at 472 nm with an isoemissive point at 436 nm with the addition of Fe(2+) salt solution is due to the formation of mononuclear Fe(2+) complex [Fe(II)(HL)(ClO(4))(2)(CH(3)CN)(2)] (1) in acetonitrile-HEPES buffer (100 mM, 1/4, v/v) at pH 4.5 and a decrease in fluorescence at 412 nm and increase in fluorescence at 482 nm with an isoemissive point at 445 nm during titration by Fe(3+) salt due to the formation of binary Fe(3+) complex, [Fe(III)(L)(2)(ClO(4))(H(2)O)] (2) with co-solvent at biological pH 7.4 have been established. Binding constants (K(a)) in the solution state were calculated to be 3.88 × 10(5) M(-1) for Fe(2+) and 0.21 × 10(3) M(-1/2) for Fe(3+) and ratiometric detection limits for Fe(2+) and Fe(3+) were found to be 2.0 μM and 3.5 μM, respectively. The probe is a "naked eye" chemosensor for two states of iron. Theoretical calculations were studied to establish the configurations of probe-iron complexes. The sensor is efficient for detecting Fe(3+)in vitro by developing a good image of the biological organelles.

In cancer progression, proteolytic enzymes like serine proteases and metalloproteinases degrade the basement membrane enabling the tumor cells to invade the adjacent tissues. Thus, invasion and metastasis are augmented by these enzymes. Simultaneous silencing of uPA and MMP9 in breast cancer cells decreased the wound healing, migratory, invasive and adhesive capacity of the cells. After simultaneous down regulation, cells were seen to be arrested in the cell cycle. There was a remarkable increase in the expression of cell to cell adhesion molecule E–cadherin, and decrease in Vimentin and Snail expression. In addition, there was a significant decrease in the expression of the stem cell marker Oct-4. In the breast tumor samples it has been observed that, tumors, expressing higher level of uPA and MMP9, express less amount of E–cadherin. It has also been observed that few tumors also show, Vimentin positive in the ductal epithelial area. Thus, our model can help for checking the aggressive tumor invasion by blocking of uPA and MMP9. Our present observations also give the concept of the presence of aggressive epithelial cells with mesenchymal nature in the tumor micro-environment, altering the expression of EMT genes.