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The synthesis, characterization by X-ray analysis and magnetic properties of a one dimensional coordination polymer {[Mn7(OH)2(dhap)2(N3)3(MeCN)4(ClO4)2]·2(MeCN)·2(ClO4)}∞ (1) are reported. The ligand dhapH4 in the complex is 2,6-bis[N,N-di(hydroxyethyl)aminomethyl]pyridine. This compound crystallizes in the monoclinic space group C2/c. Each [Mn7(OH)2(dhap)2(N3)3(MeCN)4(ClO4)2] unit (abbreviated by Mn7) is linked end-to-end by azido ligands to its neighboring units to form a one dimensional polymer. Magnetic susceptibility measurements indicate that the polymer is composed of S = 8 units with inter-Mn7-unit antiferromagnetic coupling. The Jahn–Teller axes of the Mn7 units are arranged in a zigzag manner along the polymer chain which induces spin canting at low temperatures. The slow magnetization relaxation at low temperatures was evidenced by observing out-of-phase signals in ac magnetic susceptibility measurements that give Ueff = 47.5 K and Δ0 = 2.7 × 10−13 s. This phenomenon also indicates that this one dimensional coordination polymer functions as a single-chain magnet (SCM).

Physical and chemical quality including vitamin C, TSS, browning index and pH and sensory quality indexes including appearance, color and odor of orange juice were studied during the storage under ambient temperature, take oxygen scavenging films (OSF) as the packaging materials, and high barrier packaging and normal food packaging as the control group. Experimental results showed vitamin C, total soluble solid and pH value of orange juice packed in oxygen scavenging packaging were higher than that in control group, browning index was significantly lower than that in control group, and the sensory quality evaluation was better than that in control group after storage for 5 weeks. This indicated that oxygen scavenging packaging can remove oxygen in package headspace, prevent oxygen from penetrating into package from outside, and form a lower oxygen concentration environment in package. And it can obviously retard the degradation of vitamin C and sugar, delay the browning, delay the decline of orange juice quality, and prolong the shelf life of orange juice.

Porous cermets composites were prepared from mixed powders (Ni, Al, Ti and C) by SHS (Self-propagating High-temperature Synthesis) method. When Ni-Al intermetallics bonded TiC porous cermets substitute for TiC ceramic as perform in the process of manufacturing Ni-Al/TiC composites by pressureless melt infiltration, the wetting of the ceramic material and Ni-Al intermetallics can be improved. In this study, the microstructure and mechanical properties (density and compressive resistance strength) were reported. It is learnt from the study that the relation between the open porosity and the pore size does not exist, the former depends on the green density, and the latter depends on the particle size of the nickel powder. The porous cermets with porosity ranging from 40% to 50%, pore size from 1μm to 300μm, and the compressive resistance strength about 15 MPa can be prepared by SHS. SEM observations of fracture surface suggest the fracture mode is brittleness fracture, and the microstructures of the porous cermets are very homogenous.

A kind of novel lead-free ferroelectrics, potassium bismuth titanate, K0.5Bi0.5TiO3 (KBT), has been prepared by sol–gel-hydrothermal and sol–gel routes, respectively, and the structural characters of as-synthesized powders were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The results indicated that sol–gel-hydrothermal route led to the formation of KBT nanowhiskers with diameters of 20 nm and lengths of 1 μm, and the processing temperature was as low as 160 °C, but the normal sol–gel route tended to form KBT cubic particles of about 100–200 nm, and the processing temperature was higher than 700 °C. It is believed that the gel precursor and hydrothermal environment play an important role in the formation of the nanowhiskers at low temperature. Due to the good sinterability of nanowhiskers, the ferroelectric and dielectric properties of KBT ceramics prepared by sol–gel-hydrothermal route were super to that prepared by sol–gel route.

A new copper (II) complex [Cu(dtne)] · (ClO4)2 · CH3CH2OH, where dtne is 1,2-bis(1,4,7-triaza-1-cyclononyl)ethane, was prepared and characterized by X-ray crystallography. The result shows that in the complex the copper (II) adopts an octahedral coordination geometry. The cyclic voltammetry of the complex recorded in aqueous solution indicates a reversible one-electron redox reaction. The activity of dismutation of superoxide ( O 2 - ) of the complex in the riboflavin–methionine–nitro blue tetrazolium assay has been researched.