Sintering and compensation effect of donor and acceptor codoped 3 mol% Y 2 O 3 -ZrO 2

Addition of 0.15–0.5 mol% acceptor oxide, Al 2 O 3 , to 3 mol% Y 2 O 3 -ZrO 2 results in enhanced densification at 1350°C. The enhancement is accounted for by a liquid phase sintering mechanism. While the addition of donor oxide, Ta 2 O 5 , of 0.15–2.5 mol% at 1300–1600°C results in the decrease of final density and in the destabilization of the tetragonal (t) phase of the 3 mol% Y 2 O 3 -t-ZrO 2 (TZP). X-ray diffractometry (XRD) reveals that the Ta 2 O 5 -added 3 mol% Y 2 O 3 -ZrO 2 contains monoclinic (m) ZrO 2 phase and a second Ta 2 Zr 6 O 17 phase. The decrease is attributed to the increase of m-ZrO 2 content in these samples. Complete phase transformation from t-ZrO 2 to m-ZrO 2 observed in samples added with 2.5 mol% Ta 2 O 5 is interpreted by the compensation effect based on donor and acceptor codoping defect chemistry.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44737/1/10853_2004_Article_BF00356138.pd

Sintering and compensation effect of donor- and acceptor-codoped 3mol% Y 2 O 3 -ZrO 2

Addition of ∼0.15–0.5 mol% acceptor oxide, Al 2 O 3 , to 3 mol% Y 2 O 3 -ZrO 2 results in enhanced densification at 1350 °C. The enhancement is accounted for by a liquid phase sintering mechanism. The addition of donor oxide, Ta 2 O 5 , of 0.15–2.5 mol % at 1300–1600 °C results in the destabilization of tetragonal (t-) phase and the decrease of final density in 3 mol% Y 2 O 3 -TZP (tetragonal ZrO 2 polycrystals). X-ray diffractometry (XRD) reveals that the Ta 2 O 5 -added 3 mol% Y 2 O 3 -ZrO 2 contains monoclinic (m-) ZrO 2 and a second phase of Ta 2 Zr 6 O 17 . The decreasing in final density is attributed to the increase of m-ZrO 2 content. Complete destabilization of t-ZrO 2 to m-ZrO 2 in samples added with 2.5 mol% Ta 2 O 5 is interpreted by the compensation effect based on donor- and acceptor-codoping defect chemistry.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44714/1/10853_2005_Article_BF01166021.pd

Intoxicated witnesses: Testing the validity of the Alcohol Myopia Theory.

In an assessment of the Alcohol Myopia Theory, the effects of alcohol on an eyewitness’s recall of high and low salience details were investigated. In laboratory study 1, participants watched a staged videoed theft whilst either sober (control or placebo), above (MBAC=0.09%) or below (MBAC=0.06%) the UK drink-drive limit. A week later a free-recall and recognition test were completed. Intoxication was not found to reduce recall accuracy using either recall task. In Study 2, while on a night out participants watched the videoed theft with high (MBAC=0.14%) or low (MBAC=0.05%) BAC’s. A week later the free-recall and recognition test were attempted. High BAC’s were seen to impair recall when memory was assessed through free-recall but not with the recognition test. Neither study found the attention narrowing predicted by AMT using either recall technique, although poor recall for low salience details in all groups may have contributed to this result

Surveillance of insecticide resistance in head lice using biochemical and molecular methods

Treatment of head louse infection is primarily through topical insecticides. However, there is growing evidence of resistance. A representative population sample was tested using biochemical and molecular methods; it was shown that, in Wales, treatments containing pyrethroids are likely to be less effective in controlling head louse infection than those containing organophosphates