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Copper-doped ZnO (ZnO:Cu) films are prepared on silicon substrates by filtered cathodic vacuum arc technique at room temperature using a Zn target containing 5 at. % of Cu. X-ray diffraction, x-ray photoelectron spectroscopy, and transmission electron microscopy reveals that no ferromagnetic-related secondary could be detected in ZnO:Cu.

Surface that durably and anti-fouling are of interest for fundamental research and industrial application in the heat exchanger equipment. In the present study, hierarchical micro/nano structure (HMNS) is fabricated by electrical discharge machining (EDM) method. The morphology, metallographic and crystalline structures as well as corrosion resistance of the HMNS are characterized. The micro/nano structure improves the corrosion resistance and hydrophobic property of the surface. The HMNS, with the grain size dimension of 1.5–11 μm, shows an improved contact angle of 124.9° ± 5.4°. The co-effect of hydrophobic and corrosion resistance endows the HMNS with a superior anti-fouling property than that of polished surface. Fouling adhesion experiments shows that, after being immersed in CaCl2 + Na2CO3 solution for 72 h at 50 ℃, there are only a few fouling adhere on the HMNS and the adhered fouling is loose and easy to fall off. Moreover, after 50 times of semitransparent tape adhesion, the HMNS still in the hydrophobic status with slightly decreases (4.09%–9.38%) of contact angle, which indicates that the HMNS is durably and suitable for industrial application. There is an industrial prospect for fabricating anti-fouling heat transfer surface by a low cost and environmentally friendly one-step EDM process. Keywords: Electrical discharge machining, Hierarchical micro/nano structure, Hydrophobic, Anti-fouling, Corrosion resistance

Graphene nanosheet films with improved durability and load capability are highly desired to realize the engineering application of graphene as solid lubricants. Here, we report a general approach to fabricate anchored graphene nanosheet films (A-GNSF), which is based on the selective electrochemical dissolution of graphene-containing metal matrix composites. A-GNSF are composing of many anchored graphene nanosheets, whose parts of basal plane expose on the graphene-containing metal matrix composite's surface while other parts of their basal plane anchor into the composite. The microstructure evolution of the A-GNSF as a function of the duration of selective electrochemical dissolution and the graphene content in composites is investigated and is correlated with their tribological performance. The mechanism on reduction of friction and wear for A-GNSF is also discussed. The results show the unique architecture of the A-GNSF greatly contributes to the rapid formation and the stability of the in-situ developed graphene sliding against graphene lubricating interface. As a consequent, A-GNSF show a friction coefficient as low as 0.14, excellent wear resistance and long lifetime under a contact pressure that is up to 0.88 GPa. Keywords: Graphene, Durability, Load capability, Tribolayer, Transfer layer

Porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2 can cause reproductive failure in pigs, and swine are often simultaneously infected by combinations of the three viruses. We here report the development of a SYBR Green I-based multiplex real time PCR assay for simultaneous detection of porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2. Three pairs of specific primers were designed for the porcine parvovirus-VP2, porcine pseudorabies virus-gH and porcine circovirus type 2-ORF2 genes. Viral genomes were identified based on their distinctive melting temperatures in singleplex PCR reactions. The melting temperature was 74.5 °C for the 313 bp amplicon of porcine parvovirus-VP2 gene, 87.5 °C for the 355 bp amplicon of porcine pseudorabies virus-gH gene and 80.5 °C for the 171 bp amplicon of the porcine circovirus type 2-ORF2 gene, respectively. The detection limit of the method ranged from 0.01-0.03 TCID50/ml for the three viruses. In addition, porcine parvovirus, porcine pseudorabies virus and porcine circovirus type 2 viral loads were measured in 100 field samples, and the result showed that the concordance between real-time PCR and conventional PCR was 60.42%. The sensitivity and specificity of real-time PCR were 100% and 100%, while those of conventional PCR were 40.83% and 72.22%, respectively.

Presents information on a study which prepared four 4'-dibromobiphenyl nanocrystals with different sizes by reprecipitation method. Details of experimental procedures; Results and discussion; Conclusion.

Development and selection of an ideal scaffold is of importance for tissue engineering. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) is a biocompatible bioresorbable copolymer that belongs to the polyhydroxyalkanoate family. Because of its good biocompatibility, PHBHHx has been widely used as a cell scaffold for tissue engineering. This review focuses on the utilization of PHBHHx-based scaffolds in tissue engineering. Advances in the preparation, modification, and application of PHBHHx scaffolds are discussed.

SRY-related high-mobility-group box 9 (Sox9) gene is a cartilage-specific transcription factor that plays essential roles in chondrocyte differentiation and cartilage formation. The aim of this study was to investigate the feasibility of genetic delivery of Sox9 to enhance chondrogenic differentiation of human umbilical cord blood-derived mesenchymal stem cells (hUC-MSCs). After they were isolated from human umbilical cord blood within 24 h after delivery of neonates, hUC-MSCs were untreated or transfected with a human Sox9-expressing plasmid or an empty vector. The cells were assessed for morphology and chondrogenic differentiation. The isolated cells with a fibroblast-like morphology in monolayer culture were positive for the MSC markers CD44, CD105, CD73, and CD90, but negative for the differentiation markers CD34, CD45, CD19, CD14, or major histocompatibility complex class II. Sox9 overexpression induced accumulation of sulfated proteoglycans, without altering the cellular morphology. Immunocytochemistry demonstrated that genetic delivery of Sox9 markedly enhanced the expression of aggrecan and type II collagen in hUC-MSCs compared with empty vector-transfected counterparts. Reverse transcription-polymerase chain reaction analysis further confirmed the elevation of aggrecan and type II collagen at the mRNA level in Sox9-transfected cells. Taken together, short-term Sox9 overexpression facilitates chondrogenesis of hUC-MSCs and may thus have potential implications in cartilage tissue engineering.