Static and MAS 207 Pb NMR spectra of a series of lead oxides, including the electronic materials PbTiO 3 (PT), PbZrO 3 , Pb(Zr 0.53 Ti 0.47 )O 3 , Pb(Mg 0.33 Nb 0.67 )O 3 (PMN), and 0.66PMN/0.34PT, have been measured. The chemical shift parameters (δ iso , δ aniso , and η) and the spin-lattice relaxation times have been determined for most of these compounds. The symmetry of the local environment of the lead(II) site and the covalency of the Pb-O bonds are determined to be the best indicators of the 207 Pb chemical shift parameters. Ionic compounds (e.g., PbSO 4 and Pb(NO 3 ) 2 ) have isotropic chemical shifts from -3600 to -2500 ppm and small absolute anisotropic chemical shifts (<500 ppm); while covalent lead oxides (e.g., PbO and Pb 3 O 4 ) have isotropic chemical shifts from 800 to 1900 ppm and large absolute anisotropic chemical shifts (1900 to 2600 ppm). PbTiO 3 and PbZrO 3 have intermediate isotropic (-1419 to -1017 ppm) and anisotropic chemical shifts (-838 to -546 ppm) consistent with an intermediate degree of covalent bonding. Pb(Zr 0.53 Ti 0.47 )O 3 , PMN, and 0.66PMN/0.34PT have single broad asymmetric 207 Pb NMR resonances, with chemical shifts and line widths consistent with Pb-O bonds that are less covalent than those in PbO and more covalent than those in PbTiO 3 and PbZrO 3 . For the 207 Pb NMR spectra of Pb(Zr 0.53 Ti 0.47 )O 3 , PMN, and 0.66PMN/0.34PT, chemical shift dispersion is a significant contribution to the line width, consistent with the presence of a range of inequivalent lead(II) sites in these disordered perovskite materials.

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This study examined (1) the relative prevalence of childhood abuse and other pathological childhood experiences in China reported by outpatients with borderline personality disorder (BPD), with other personality disorders, and without personality disorders; and, (2) whether the primary predictors of BPD in North America are associated with the development of BPD in China. The childhood experiences of 203 outpatients with BPD, 109 outpatients with other personality disorders, and 70 outpatients without Axis II diagnoses were assessed with the Chinese version of the Childhood Experience of Care and Abuse Questionnaire (CECA.Q). Patients with BPD reported significantly more physical, emotional, and sexual abuse than either comparison group. Four types of childhood experiences were significant predictors of BPD: maternal neglect, paternal antipathy, sexual abuse, and maternal physical abuse. The findings suggest that maternal physical abuse is as strong a predictor of BPD in China as sexual abuse, a finding not replicated in North America.