KNbO 3 (KN) nanowires having a tetragonal structure or a polymorphic phase boundary (PPB) structure, which contains both tetragonal (P4mm) and orthorhombic (Amm2) structures, are formed at low temperatures. The presence of tetragonal and PPB KN nanowires is attributed to the existence of OH À and H 2 O defects. Further, the tetragonal and PPB KN nanowires change to orthorhombic KN nanowires in the temperature range between 300 and 400 C owing to desorption of the lattice hydroxyl group. A composite consisting of polydimethylsiloxane (PDMS) and KN nanowires having a PPB structure shows large dielectric constant and low dielectric loss values of 9.2 and 0.5%, respectively, at 100 kHz.Moreover, a nanogenerator (NG) synthesized using the PPB KN nanowires exhibits the largest output voltage and current among NGs synthesized using the tetragonal or orthorhombic KN nanowires. In particular, the NG containing 0.7 g of PPB KN nanowires shows an output voltage of 10.5 V and an output current of 1.3 mA; these values are among the highest ever reported for NGs synthesized using a lead-free composite. In addition, this NG exhibited the maximum output power and energy conversion efficiency, which were 4.5 mW and 0.9%, respectively, for an external load of 1.0 MU.

This work reports a novel FeO@polydopamine/Au/polydopamine core/shell nanocomposite toward a magnetically separable nanocatalyst. Because the polydopamine (PDA) layer-sandwiched Au nanocrystals were prepared by a layer-by-layer method, the content of Au could be controlled by varying the Au shell number (such as burger-like FeO@PDA/Au/PDA/Au/PDA). FeO@PDA/Au/PDA exhibited excellent catalytic activity in reducing p-nitrophenol because the substrate could penetrate the PDA shell. Owing to the protection of the PDA shell, FeO@PDA/Au/PDA presented higher cyclability than FeO@PDA/Au. The activity of FeO@PDA/Au/PDA maintained 95% after 7 cycles, while that of FeO@PDA/Au was only 61%. The detailed cycling catalytic mechanism was investigated, and it was found that the catalytic rate of FeO@PDA/Au/PDA/Au/PDA was faster than that of FeO@PDA/Au/PDA because of the higher Au content. Interestingly, this method could be extended for other magnetic nanocomposites with two different kinds of noble metal nanocrystals integrated within one particle, such as FeO@PDA/Au/PDA/Ag/PDA and FeO@PDA/Au/PDA/Pd/PDA.

The object was to assess anxiety and depression during in vitro fertilisation (IVF) treatment and determine IVF-related psychological factors in infertile Chinese women. The self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to evaluate anxiety and depression among 842 patients, respectively. A univariate analysis was used to compare variables among three SAS groups and three SDS groups. Anxiety and depression were both represented in 21.3% of the cases. Patients <35 years tended to be more anxious. In women <35 years, the SDS scores were higher with lower educational backgrounds and female or couple's infertility, while the SAS scores were higher in female or couple's infertility. In older ones, the SDS scores were higher in those with lower educational backgrounds and longer time for infertility, while the SAS scores were higher in those with lower educational backgrounds. In SAS groups 1-3, the embryo availability was 5.0 (3.0-8.0), 5.0 (3.0-8.0), and 3.0 (2.0-4.5) (p = .013); and the fertilisation rate was 91.9, 90.4, and 81.8% (p < .001), respectively. We concluded that infertile women experience anxiety and depression during IVF treatment, especially in women <35 years. Younger women with female infertility would be more anxious and depressive while higher education can protect them from depression. In older ones, they would experience more depressive with longer time for infertility and be less anxious and depressive with higher education. Anxiety affects the fertilisation rate and embryo availability.

No abstract