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The control efficacy of tea polyphenol ( TP) in combination with tea saponin ( TS) against nectarine grey mould decay caused by Botrytis cinerea and the underlying mechanism were investigated. The in vitro experiments showed that both TP and TS inhibited the mycelial growth in a dose-dependent manner, and their combinations exhibited synergistic antifungal interactions with the synergistic ratios ( SR) exceeding 1·5. The in vivo experiments showed that disease incidence and lesion diameter of grey mould of inoculated fruit were significantly lowered after being treated with the combination of TP and TS; furthermore, the activities of phenylalanine ammonia-lyase ( PAL), peroxidase ( POD), polyphenol oxidase ( PPO), chitinase and β-1,3-glucanase of inoculated fruit as well as the contents of total phenolic and lignin were significantly induced, the respiration rate of inoculated fruit was significantly decreased and therefore the quality decrease was accordingly retarded. These results revealed that TP in combination with TS could control grey mould of inoculated nectarines and their mechanism of action might be attributed to their active components, the induction of defensive system and the regulation of respiration. Significance and Impact of the Study This study demonstrates that the combination of TP and TS has exhibited synergistic antifungal interactions against Botrytis cinerea, and it suggests that their combination may be useful and effective agents for the control of nectarine grey mould decay. Such natural products therefore represent a promising alternative to synthetic fungicides in the control of nectarine postharvest diseases. [ABSTRACT FROM AUTHOR]

Abstract: ZnO nanorod arrays (NRAs) with different Na contents were prepared by thermal evaporation. Sodium pyrophosphate was adopted as the Na source. The Na contents in NRAs were determined by X-ray photoelectron spectra to be 0, 6.1, and 9.4at.%. X-ray diffraction (XRD) analyses of Na-doped ZnO NRAs were performed in experiment and by first-principle calculation with the assumption of Na substitutions. A couple of typical changes were found in XRD patterns of Na-doped ZnO. The simulation results well agreed with the experimental data, which revealed that Na mainly located at the substitutional sites in Na-doped ZnO NRAs. [Copyright &y& Elsevier]

Examines the monophasic vasoconstrictor responses to periarterial purinerguc nerve stimulation. Effects of rauwolscine on vasoconstrictor responses to periarterial electric nerve stimulation; Influence of the pulse trains at low frequency on the activation of purinergic components of sympathetic cotransmission; Role of alpha-adrenergic mechanism on the modulation of adenosine 5-triphosphate release.

Abstract: To significantly improve the performance of rubber materials, fundamental studies on rubber nanocomposites are necessary. The curing kinetics and vulcanizate properties of carbon nanotubes (CNTs)/natural rubber (NR) nanocomposites were analyzed in this paper. The pretreatment of CNTs was carried out by acid bath followed by ball milling with HRH bonding systems in experiments. The CNT/NR nanocomposites were prepared through solvent mixing on the basis of pretreatment of CNTs. The surface characteristic of CNTs and physical interaction between CNTs and NR macromolecules were analyzed by Fourier transform infrared spectroscopy (FT-IR). The vulcanization kinetics of CNT/NR nanocomposites were studied contrasting with the neat NR. The quality of the NR vulcanizates was assessed through static and dynamic mechanical property tests and scanning electron microscope (SEM). Curing kinetic parameters of the neat NR and CNT/NR nanocomposites were obtained from experiments; the results indicated that the presence of CNTs affects the curing process of the NR, and additional heating is required to cure CNT/NR nanocomposites due to its higher active energy. The dispersion of pretreated CNTs in the rubber matrix and interfacial adhesion between them were obviously improved. The physical and mechanical properties of the CNT/NR nanocomposites showed considerable increases by incorporation of the pretreated CNTs compared to the neat NR and untreated CNTs-filled NR nanocomposites. [Copyright &y& Elsevier]

Abstract: The continuous highly aligned hybrid carbon nanofibers (CNFs) with different content of acid-oxidized multi-walled carbon nanotubes (MWCNTs) were fabricated through electrospinning of polyacrylonitrile (PAN) followed by a series of heat treatments under tensile force. The effects of MWCNTs on the micro-morphology, the degree of orientation and ordered crystalline structure of the resulting nanofibers were analyzed quantitatively by diversified structural characterization techniques. The orientation of PAN molecule chains and the graphitization degree in carbonized nanofibers were distinctly improved through the addition of MWCNTs. The electrical conductivity of the hybrid CNFs with 3wt% MWCNTs reached 26S/cm along the fiber direction due to the ordered alignment of MWCNTs and nanofibers. The reinforcing effect of hybrid CNFs in epoxy composites was also revealed. An enhancement of 46.3% in Young’s modulus of epoxy composites was manifested by adding 5wt% hybrid CNFs mentioned above. At the same time, the storage modulus of hybrid CNF/epoxy composites was significantly higher than that of pristine epoxy and CNF/epoxy composites not containing MWCNTs, and the performance gap became greater under the high temperature regions. It is believed that such a continuous hybrid CNF can be used as effective multifunctional reinforcement in polymer matrix composites. [Copyright &y& Elsevier]

Abstract: A kind of composite carbon nanofibers (CNF) containing bioactive glass (BG) nanoparticles was produced for bone regeneration by a combination of electrospinning and sol–gel techniques. To produce the BG, compounds such as calcium nitrate, triethyl phosphate and tetraethyl orthosilicate were used as precursors and hydrolyzed to form a sol–gel solution, which was then added to a polyacrylonitrile (PAN) solution in N,N-dimethylformamide. The resulting mixture was electrospun to form PAN nanofibers containing the BG precursors. Upon oxidation and carbonization, the PAN nanofibers and BG precursors transformed into continuous CNF embedded with BG nanoparticles (CNF/BG). Through this fabrication technique, several CNF/BG composites were obtained by controlling the feeding ratios of the different precursors giving rise to BG nanoparticles with various compositions (i.e. containing 70–90mol% of SiO2 component). In vitro biomineralization in a simulated body fluid and co-culture with MC3T3-E1 osteoblasts studies were performed to evaluate the osteocompatibility of the CNF/BG nanoparticle composites. When compared to pure CNF, the CNF/BG composites showed an improved ability to promote the in vitro formation of apatite and MC3T3-E1 proliferation, which was found to be dependent upon the composition of BG nanoparticles. [Copyright &y& Elsevier]

Abstract: A simple method by combined molecular self assembly and surface-initiated atom transfer radical polymerization (SI-ATRP) was proposed to prepare a biologically inert surface for micropatterning active proteins. The MPEG microdomains having a short terminal poly(ethylene glycol) (PEG) unit were prepared by self assembly of 2-(methyoxy(polyethylenoxy) propyl)trimethoxy silane (MPEG-silane). The remaining local regions or poly(poly(ethylene glycol)methyl ether methacrylate-co-glycidyl methacrylate) (P(PEGMEMA-co-GMA)) microdomains were produced via SI-ATRP of PEGMEMA and GMA comonomers. The epoxy groups of the P(PEGMEMA-co-GMA) microdomains were used directly for covalent coupling of an active protein (human immunoglobulin or IgG) via the ring-opening reaction to produce the IgG-coupled microdomains. The IgG-coupled microdomains interact only and specifically with target anti-IgG, while the other antifouling microregions from self-assembled monolayers with short terminal PEG units effectively prevent specific and non-specific protein fouling. When extended to other active biomolecules, microarrays for specific and non-specific analyte interactions with a high signal-to-noise ratio could be readily tailored. [Copyright &y& Elsevier]

Abstract: Effects of untreated and pretreated carbon nanofibers (CNFs) on the crystallization behavior, friction behavior, and mechanical properties of ultra high molecular weight polyethylene (UHMWPE)/high density polyethylene (HDPE) nanocomposites prepared by a twin-screw extrusion were studied. The differential scanning calorimetry and wide angle X-ray diffraction measurements indicated that the addition of CNFs impacted the temperature of crystallization, but had no significant effects on the crystalline structure of the UHMWPE/HDPE blend. The degree of crystallinity, and the tensile strength and modulus of the UHMWPE/HDPE systems exhibited an increasing trend initially with addition of CNFs, followed by a decrease at higher contents. With the increase of untreated CNF content, the friction coefficient of UHMWPE/HDPE was decreasing and displayed less change in the process of friction. The microstructure features on the fracture surfaces and friction surfaces of the polymer blend and the nanocomposites were analyzed in detail by scanning electron microscope observations. The degree of crystallinity of the nanocomposites with the pretreated CNFs exhibited a decrease due to the better interface adhesion compared to that in the nanocomposites with the same loading untreated CNFs. The enhancement in tensile strength of nanocomposites containing 0.5wt% treated CNFs was four times higher (32%) than that of the nanocomposites containing untreated CNFs (8%) over that of the pure polymer. [Copyright &y& Elsevier]

Beijing free electron laser (BFEL) is a Compton-type mid-infrared FEL facility, with first lasing in 1993. In the past two years, two experimental stations were constructed, and the reliability and stability of BFEL improved much. The lasing time provided to the users was more than 1000 hours, and about 250 samples have been irradiated, many application items concerned. Next, BFEL will be upgraded to be user’s facilities, and other three experimental stations will be furnished. This paper describes the operation, application and upgrade plan of BFEL in details. In addition, the development of several research activities are mentioned. [Copyright &y& Elsevier]

Using a free-electron laser(FEL) source, we have studied the two-photon-absorption (TPA) effect in GaAs/AlGaAs quantum-well infrared photodetector (QWIP). The TPA-induced photoresponse in QWIPs has been measured under different FEL excitation power by the photoconductivity method. The effective-mass approximation theory is used for the QWIP structure to explain the photoresponse behavior. It is demonstrated that the TPA-induced photocarrier density is proportional to the square of the excitation power. Based on the experimental results, the TPA coefficients of QWIPs were obtained to be 0.0045, 0.0030, 0.0103, and 0.0061 cm/MW for the excitation lines of 10.6, 10.7, 11.9 and 13.2 μm, respectively. The dependence the TPA coefficients on the excitation wavelength is explained by our theoretical model. [ABSTRACT FROM AUTHOR]