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Microbial fuel cells (MFCs) have various potential applications. However, anode is a main bottleneck that limits electricity production performance of MFCs. Herein, we developed a novel anode based on a stainless steel cloth (SC) modified with carbon nanoparticles of Chinese ink (CI) using polypyrrole (PPy) as a building block (PPy/CI/SC). After modification, PPy/CI/SC showed a 30% shorten in start-up time (36.4 ± 3.3 h vs. 52.3 ± 1.8 h), 33% increase in the maximum current (12.4 ± 1.4 mA vs. 9.3 ± 0.95 mA), and 2.3 times higher in the maximum power density of MFC (61.9 mW/m2 vs. 27.3 mW/m2), compared to Ppy/SC. Experimental results revealed that carbon nanoparticles were able to cover SC uniformly, owing to excellent dispersibility of carbon nanoparticles in CI. The attachment of carbon nanoparticles formed a fluffy layer on SC increased the electrochemically-active surface area by 1.9 times to 44.5 cm2. This enhanced electron transfer between the electrode and bacteria. Further, embedding carbon nanoparticles into the PPy layer significantly improved biocompatibility as well as changed functional group contents, which were beneficial to bacteria adhesion on electrodes. Taking advantage of high mechanical strength and good conductivity, a large-size PPy/CI/SC was successfully prepared (50 × 60 cm2) demonstrating a promising potential in practical applications. This simple fabrication strategy offers a new idea of developing low cost and scalable electrode materials for high-performance energy harvesting in MFCs.

Bioanodes are core components that affect the performance of microbial fuel cells. In this paper, a superior three-dimensional graphite foam electrode is prepared with rapid gasification of liquid nitrogen and expanding a graphite foil into an expanded graphite foam. With following thermal treatment, thermal treated expanded graphite foam is also prepared. The characterization results indicate that no doping or oxidation occurs during the preparation, which retains a good conductivity and biocompatibility. Microbial fuel cells equipped with expanded graphite foam and thermal treated expanded graphite foam exhibit significantly higher output voltage and power density than graphite foil. Furthermore, cyclic voltammetry and electrochemical impedance spectroscopy are further conducted to investigate the electrochemical performance of different anode materials. Results confirm that the bioelectrochemical activities are enhanced on the fabricated electrodes. Electrochemical active surface area measurement reveals that, other than surface area increase, the graphene-like electrode morphology promotes electron transfer processes. This fast and easy fabrication strategy allows massive production of three-dimensional graphite foam based high performance anodes for microbial fuel cells.

Snow chrysanthemum (Coreopsis tinctoria Nutt.), a world-widely well-known flower tea material, has attracted more and more attention because of its beneficial health effects such as antioxidant activity and special flavor. In this study, a high performance liquid chromatography coupled with diode array detection and mass spectrometry (HPLC-DAD-MS) and 2,2'-azinobis(3-ethylbenzthiazoline-sulfonic acid)diammonium salt (ABTS) based assay was employed for comparison and identification of antioxidants in different samples of snow chrysanthemum. The results showed that snow chrysanthemum flowers possessed the highest while stems presented the lowest antioxidant capacities. Fourteen detected peaks with antioxidant activity were temporarily identified as 3,4',5,6,7-pentahydroxyflavanone-O-hexoside, chlorogenic acid, 2R-3',4',8-trihydroxyflavanone-7-O-glucoside, flavanomarein, flavanocorepsin, flavanokanin, quercetagitin-7-O-glucoside, 3',5,5',7-tetrahydroxyflavanone-O-hexoside, marein, maritimein, 1,3-dicaffeoylquinic acid, coreopsin, okanin and acetyl-marein by comparing their UV spectra, retention times and MS data with standards or literature data. Antioxidants existed in snow chrysanthemum are quite different from those reported in Chrysanthemum morifolium, a well-known traditional beverage in China, which indicated that snow chrysanthemum may be a promising herbal tea material with obvious antioxidant activity.

A multi-layered Ti (50 nm)/Ni (50 nm)/Ti (50 nm)/Au (50 nm) metallic contact to Al-doped ZnO thin films (ND = 3.64 × 1019 cm−3) was reported in this paper. The as-deposited Ti/Ni/Ti/Au scheme showed a specific contact resistivity of 2.07 × 10−4 Ω cm2. And a lowest specific contact resistivity of 6.69 × 10−5 Ω cm2 was obtained after annealing at 500 °C. The specific contact resistivity showed a decreasing tendency with the annealing temperature up to 500 °C. However, for the sample annealed at above 600 °C, the I–V curves revealed gradual Schottky transformation. Interface diffusions and reactions induced by annealing treatment were found to be responsible for the decrease of Ohmic contact resistivity and the Schottky transformation.

One of the fundamental questions is how we can enhance our relationships with the people in our social networks. The combination of frequent engagement, deep interaction, and time spent together are what constitute to build a stronger relationship. With this knowledge in mind, it is not surprising to see many scholars claim that social networking sites may help us to re-connect some lost relationships, but has limited ability to strengthen an existing relationship. Surprisingly, from a survey we conducted, we found that most people who use Facebook or scholat.com (a scholar-oriented social networking site) claim that their relationships with some of their friends are improved, even though they do not have any in-depth or personal conversation with them and they can understand their friends better even without any communication. It contradicts with what we have known. It seems that a relationship can be improved with Facebook or scholat.com alone. In this paper, we try to analyze this finding and explain it using communication model and visualized analysis. We conclude how communication model changes as time goes and how it re-defines the meaning of communication.

The electric properties of ITO thin film after UV or IR laser annealing and wet etching was analyzed via grazing incidence in-plane X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectra and residual stress measurement. The laser annealing process readily induced microcracks or quasi-microcracks on the ITO thin film due to the residual tension stress of crystalline phase transformation between irradiated and non-irradiated areas, and these defects then became the preferred sites for a higher etching rate, resulting in discontinuities in the ITO thin film after the wet etching process. The discontinuities in the residual ITO thin film obstruct carrier transmission and further result in electric failure.

The authors report growth of stable Na-doped p-type ZnO films through pulsed laser deposition. Magnetic field dependent Hall-effect measurements demonstrate the firm p-type conductivity of the Na-doped films. The Na related acceptor level was estimated to be ∼164 meV by temperature-dependent photoluminescence and low temperature photoluminescence excitation spectra. ZnO p–n homojunction light-emitting diode consisting of Al-doped n-type ZnO and Na-doped p-type ZnO was fabricated on Si substrates. The diode showed evident rectification behavior with threshold voltage of ∼3.3 eV. The electroluminescence from the diode was observed at 110 K, consisting of three emission bands of 2.24 eV, 2.52 eV, and 3.03 eV from the radiative recombinations in the p-type layer. This work firmly demonstrates that Na could be a good dopant to create stable p-type ZnO.

Co-free LaNi 4.92 Sn 0.33 alloy samples were prepared by first induction melting and subsequent melt-spinning at different quenching rates, and their microstructure and electrochemical properties were comparatively investigated and compared. The results reveal that the as-cast alloy is of a coarse dendrite structure consisting of two distinct CaCu 5 major phases and a scattered minor Sn phase, has high volume expansion and pulverization rates on hydriding and noticeable composition segregation, resulting in a rather poor cycling stability ( S 200 = 42.7 % ). However, the melt-spun alloys prepared at higher quenching rates are highly homogeneous in composition, of the single CaCu 5 phase in very fine cellular structure, have lower volume expansion and pulverization rates on hydriding, leading to a noticeably improved cyclic stability ( S 200 = 62.5 – 78 % ), although their activation rate, initial capacity and high-rate dischargeability are slightly lowered. It is believed that the great improvement in cycling stability of the melt-spun alloys is mainly due to their lower degree of pulverization on hydriding and the higher uniformity in composition, and the relatively lower high-rate dischargeability is mainly due to the decrease in both the electrocatalytic activity and the hydrogen diffusion rate in the alloy bulk.

In this paper, the effect of Ni content on the crystal structure and electrochemical properties of the La 2 MgNi x ( x = 8.7–9.9) alloys was investigated. All the alloys are composed of a main phase with hexagonal PuNi 3 -type structure and a small quantity of impurity phases (LaNi 5 , MgNi 2 ). The increase of Ni content in the alloys leads to a decrease in both the cell volume and the hydride stability, and leads to a noticeable decrease in cell volume expansion rate (Δ V / V ) on hydriding. As Ni content increases, the discharge capacity of the alloys at 50 mA/g increases slightly and passes through a maximum of 411.5 mAh/g at x = 9.0, the high-rate dischargeability of the alloy electrodes at 800 mA/g (HRD 800 ) improves greatly from 38.8 ( x = 8.7) to 84.4% ( x = 9.9). The increase of high-rate dischargeability of the Ni-rich alloys is ascribed to the increase of the electrocatalytic activity of the alloy electrode and the higher diffusion rate of hydrogen in the bulk of the alloys. In the composition range of x = 8.7–9.6, the cycling stability ( S 100 ) of the alloys increases with increasing of Ni content, increasing from 54.1 ( x = 8.7) to 63.4% ( x = 9.6). The improvement in cycling stability is mainly attributed to the lower cell volume expansion of the Ni-rich alloys on hydriding.

The effect of Al substitution for Ni on the structure and electrochemical properties of La 2 Mg(Ni 0.8− x Co 0.2 Al x ) 9 ( x = 0–0.03) quinary alloys was investigated. All alloys consisted of a main phase with hexagonal PuNi 3 -type structure and a small quantity of the impurity phase (La,Mg) 2 Ni 7 . The increase of Al substitution in the alloys leads to an increase in both the cell volume and the hydride stability but a decrease in unit cell volume expansion rate. The increase of Al content leads to some decrease in both the discharge capacity and the high-rate dischargeability (HRD) but leads to a significant improvement in cycling stability of the alloys. Among the alloys studied, the alloy with x = 0.02 showed a high discharge capacity of 375.9 mAh/g and the best cycling stability ( S 150 = 77.8%) but a poor high-rate dischargeability (HRD 800 = 8.3%). The decrease of HRD of the alloys is ascribed to the decrease of electrocatalytic activity for the hydrogen electrode reaction and the lower diffusion rate of hydrogen in the bulk of the alloys, while the improvement in cycling stability is mainly attributed to the decrease of V H of the hydride phase.

Composite coatings were fabricated on the surface of pure titanium and Ti–6Al–4V by laser alloying with boron and graphite powders. The results show that with the addition of Ce 2 O 3 and Y 2 O 3 , not only the compounds but also the microstructures of the coatings are refined compared with that without rare earth (RE) oxides. The mechanism of the microstructural refinement by the addition of RE oxides is discussed in this paper.

Composite coatings were fabricated by laser alloying of titanium alloy Ti–6Al–4V with graphite and silicon mixed powders. X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) analysis indicate that the coatings mainly consist of preeutectic TiC and eutectic Ti 5 Si 3 + β (Ti). The test results show that the composite coatings, thickness of about 0.6 mm, surface microhardness of about 1500 HV 0.1 , have a lower friction coefficient and a much higher wear resistance than the as-received sample.

The effect of replacing part of Ni by Al in La2MgNi9 alloy on the structure and electrochemical properties of the thus formed La2Mg(Ni1−xAlx)9 ( x = 0 – 0.05 ) quaternary alloys was investigated. All alloys consisted of a main phase with hexagonal PuNi3-type structure and a small quantity of an impurity phase (La2Ni7). The increase of Al content in the alloys leads to an increase in both the cell volume and the hydride stability, and leads to a noticeable decrease in cell volume expansion rate ( Δ V / V ) on hydriding. The increase of Al content leads to some decrease in both the discharge capacity and the high-rate dischargeability (HRD) but leads to a significant improvement in cycling stability of the alloys. The decrease of HRD of the alloys is ascribed to the decrease of electrocatalytic activity for the hydrogen electrode reaction and the lower diffusion rate of hydrogen in the bulk of the alloys, while the improvement in cycling stability is mainly attributed to the decrease of V H of the hydride phase.

An ecological survey was carried out at bimonthly intervals for 2 years from 2000 to 2002 in the intertidal granite shore at Chengshan Cape, on the northwest coast of the Yellow Sea. Significant differences in macroalgal composition were evident in different seasonal assemblages. The highest species richness was found from April to August, and the lowest in October. In all the seasonal assemblages surveyed, Rhodophyta showed the highest species richness, Phaeophyta ranked second and Chlorophyta last. Macroalgal biomass peaked in August (246 gm-2). From December to February cold-water species, such asEnteromorpha intestinalis, Porphyra spp., Gelidium amansii, Halymennia sinensis, Laminaria japonica and Polysiphonia urceolata, dominated the assemblage.In June warm-temperate and subtropical species became dominant. Species diversity peaked in April and then declined throughout the year until December. The seasonal assemblages surveyed could be grouped into an Enteromorpha-Corallina-Ulva dominated winter-spring association, a Sargassum-Ulva-Corallina dominated summer association and an Ulva-Gymnogongrus-Sargassum dominated autumn association.Regression analysis showed that changes in seawater temperature were the main influence on macroalgal biomass. Assemblage structure is influenced by substrate heterogeneity resulting from wave action at Chengshan Cape.

Effect of La/Mg ratio on the structure and electrochemical properties of La x Mg 3− x Ni 9 ( x =1.6–2.2) ternary alloys was investigated. All alloys are consisted of a main phase with hexagonal PuNi 3 -type structure and a few impurity phases (mainly LaNi 5 and MgNi 2 ). The increase of La/Mg ratio in the alloys leads to an increase in both the cell volume and the hydride stability. The discharge capacity of the alloys at 100 mA/g increases with the increase of La/Mg ratio and passes though a maximum of 397.5 mAh/g at x =2.0. As the La/Mg ratio increases, the high-rate dischargeability of the alloy electrodes at 1200 mA/g HRD 1200 decreases from 66.7% ( x =1.6) to 26.5% ( x =2.2). The slower decrease of HRD 1200 (from 66.7 to 52.7%) of the alloys with x =1.6–2.0 is mainly attributed to the decrease of electrocatalytic activity of the alloys for charge-transfer reaction, the more rapid decrease of HRD 1200 of the alloys with x >2.0 is mainly attributed to the lowering of the hydrogen diffusion rate in the bulk of alloy. The cycling capacity degradation of the alloys is rather fast for practical application due to the corrosion of La and Mg and the large V H in the hydride phase.

Crystalline hexagonal B(N 1 m x C x ) and cubic B-C-N compounds have been synthesized from a precursor produced from melamine and boric acid by application of high temperature and high pressure. The synthesized products were characterized by X-ray diffraction. The lattice parameters for the hexagonal crystal are a=2.506 A, c=6.657 A, and that for the cubic crystal is a=3.596 A. The X-ray photoelectron spectra of the B-C-N compound indicate the presence of B-N, C-N, C-C, and B-C bonds, which suggests that boron, carbon, and nitrogen atoms all bond with one another and that the B-C-N crystal is a compound in which the three kinds of atoms are mixed atomically. The composition of the B-C-N compound is B 0.47 C 0.23 N 0.30 . A strong absorption band at 1000∼1120 cm m 1 attributable to the cubic B-C-N phase is observed in the infrared spectrum. The photoluminescence spectrum of hexagonal B-C-N powder measured at room temperature features a broad peak centered at 374 nm, corresponding to the band-edge emission ...

The adsorption of lysozyme from phosphate-buffered saline (pH 7.0) onto a quartz crystal interface was investigated in situ using an electrode-separated piezoelectric sensor (ESPS). Increasing amounts of lysozyme adsorbed onto a quartz crystal surface resulted in linearly decreasing oscillating frequencies of the ESPS. The lysozyme adsorbed is partially desorbed after rinsing with the phosphate-buffered saline. The amounts adsorbed reversibly and irreversibly were estimated. The influence of the surface roughness of the quartz crystal on the adsorption density measurement is discussed.

The plastic properties of three kinds of low-carbon steel sheets were examined by means of the uniaxial tensile test and the planestrain tensile test. The specimens were painted with grid pattern and pulled in a tensile testing machine while precision photographs of the deformed grid pattern were taken. The strain-hardening characters were measured and calculated by applying Wagoner's method. The yield behavior and strain-hardening characters depended primarily on the rolling process. The stress-strain curves showed that an evidently yield strain exists in the continuous annealed steel sheets and not in the others. The forming limit strains of these steel sheets were experimentally determined for the uniaxial tension and plane-strain tension. It was clarified that sheet breaks generally due to localized necking (localized-type instability). In the plane-strain tension, the crack was initiated at the center of the specimen by shear deformation and then propagated. The left-hand sides of the forming limit diagrams (FLD) for each kind of the specimens were calculated.

The effects of bilirubin on the membrane motion parameters of human erythrocyte membrane were determined by the spin labelled ESR method. It causes a decrease in the order parameter and an increase in the corresponding fluidity of the lipid molecules. Bovine serum albumin was found to inhibit effectively the effects due to bilirubin. The disturbance to the organization of membrane molecules by bilirubin as well as the protective effects of serum albumin are discussed on the basis of the experimental results.