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The more efficient and hydrophobic modificated ammonium polyphosphate (M-APP) and charring agent (M-CA) were prepared based on sol–gel method, and they were used in the preparation of water-resistant and flame-retardant polypropylene (PP) composites. The results showed that the contact angles of M-APP and M-CA were 135.11° and 137.89°, respectively. The flame-retardant and thermal properties of the PP composites were also studied. The results showed that the flame retardancy of PP loaded with 30 mass% intumescent flame retardant (M-APP/M-CA = 3:1) was significantly increased. The limiting oxygen index (LOI) reached 36.8% and passed UL-94 V-0. The peak heat release rate and total heat release of the PP composite decreased from 1011.77 to 134.43 kW·m−2 and 100.58 to 6.86 MJ·m−2, respectively. The peak smoke production rate and total smoke release decreased from 0.13 to 0.0056 m2·s−1 and 1453.09 to 74.82 m2·m−2. The PP composite with M-APP/M-CA = 3:1 also exhibited excellent water resistance, and it could still reach UL-94 V-0 after soaking in 70 ℃ water for 168 h.

The as-cast microstructures and mechanical properties of Al-Si-Mg-Cu-Ti alloys with and without Sc were investigated by metallographic microscope, field emission scanning electron microscope, energy spectrum analysis, transmission electron microscope and universal testing machine. The result shows that adding 0.20wt.% Sc into the casting alloy can refine the grain, change the growth morphology from dendrite to fine equiaxed grain, and the morphology of eutectic Si by rough laminar structure into fine fibrous. The tensile strength of alloy with 0.20wt.% Sc is up to 304.4 MPa after T6 heat treated, which is close to that of 6061 forging aluminum alloy.

Paecilomyces victoriae was selected to transform androstenedione (AD). Two products were obtained and identified as 7α-Hydroxyandrostenedione, 7α-Hydroxy-17α-methyltestosterone, respectively, by MS and NMR.

Progesterone was biotransformed byAspergillus ustusin this paper. Two products were obtained and they were identified as 11α-hydroxyprogesterone and 11α,15β-dihydroxyprogesterone by NMR and MS. The fermentation process of biotransformtion had been studied with HPLC and 11α-hydroxyprogesterone was the main product.

CoFe2O4–Pb(Zr0.52Ti0.48)O3 (CFO–PZT) multilayered composite film was prepared on Pt/Ti/SiO2/Si substrate via a sol–gel method and spin-coating technique. Results show that PZT and CFO phases exist in the composite film, calcined at 700 °C, besides substrate phase, and no obvious impurity phases can be detected. The composite film exhibits layered structure with obvious boundary between CFO and PZT films. Ferroelectric and ferromagnetic properties were simultaneously observed in the composite film, evidencing the ferroelectric and ferromagnetic properties in the composite film. The composite film exhibits both good magnetic and electric properties, as well as, magnetoelectric (ME) effect. The saturation magnetization value of the composite film is lower than that of the pure CFO film derived by the same processing as a result of the effect of the nonferromagnetic PZT layers. Ferroelectric hysteresis loops reveal that saturated polarization and remanent polarization of the composite film are lower than those of the pure PZT films. The composite film exhibits a very large ME effect, which makes the composite film attractive for technological applications as devices.

Brillouin measurements have been made of the spin dynamics of high-density two-dimensional hexagonally ordered 20 nm diameter Fe48Co52 nanowire arrays, with various interwire spacings, as a function of longitudinal magnetic field. The experimental data are analyzed within the Arias-Mills theory based on interwire dipolar couplings in the arrays. The results provide conclusive evidence of collective spin waves arising from the dipolar coupling which is manifested as a reduction in spin wave frequency with decreasing interwire spacing.

Large scale Sb-doped ZnO nanorod arrays were grown utilizing electrochemical solution method with suitable combination of Zn(NO 3 ) 2, HMT and SbCl 3 precursors. The influences of the pH value and the substrate on the morphology and the crystallization of Sb-doped ZnO nanorods were investigated in detail. The formed Sb-doped ZnO nanorods were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Characteristics of luminescence and crystal qualities were represented by the room temperature photoluminescence spectroscopy. It was found that the pH value had a great effect on the luminescent intensity of the ultraviolet peak and the defect-related luminescence peak. The Sb-ZnO nanorods with a hexagonal wurtzite structures fabricated under the pH value of 5 showed an intense ultraviolet emission and a weak visible emission, demonstrating the good crystal quality of the nanorods. For the substrates of flexible conductive woven nickel-copper fibers, ITO conductive glass and commercial AZO conductive glass, well-crystallized Sb-doped ZnO nanorods can be all achieved. But the crystallographic orientation of nanorods strongly relied on the substrate type.

Sb-doped ZnO nanorods were fabricated via electrochemical methods. SbCl3, Zn(NO3)2 and hexamine mixed solution were used as a precursor. The morphology, composition and crystallinity of nanorods were characterized using a field emission scanning electron microscope, energy dispersive X-ray spectroscopy and X-ray diffraction, respectively. The transmitted spectrum was used to investigate optical properties of Sb-doped ZnO arrays. Single Sb-doped ZnO nanorod field effect transistors were constructed via standard photolithography process. The dependence of nanorod resistance on the temperature from 5K to 300K and the current versus voltage curve of the field effect transistor at different temperature from 100K to 300K were measured. The Sb-doped nanorod showed different electrical properties following the change of temperature. Figure 1

A simple sol–gel spin-coating technique was developed to prepare FePt films. The calcining temperature was found to have great influences on the film’s crystalline structure and magnetic properties...

Cobalt ferrite nanotubes with diameter of 50 nm were prepared using a simple sol–gel process within the pores of anodic aluminum oxide (AAO) template. SEM, TEM, XRD, VSM were used to characterize t...