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Carbon nanotubes (CNTs) have aroused widespread concern for their unique structure and excellent properties in physical, chemical and mechanical. Fileds copper-nickel alloy (Cu-Ni) is a kind of important conductive metal materials that can be widely used in electric, magnetic, catalytic and many other fields as well. The combination of nanocomposites exhibit excellent comprehensive properties which it make it one of the most promising areas at present. This paper shows the preparation of the work and the test result of carbon nanotubes (CNTs) load the nanocopper-nickel alloy (Cu-Ni/CNTs) composite materials that the nanocomposite can be used as an electrode material and fuel cell. In this paper, carbon nanotubes (CNTs) which were acidized by mixed acid are used as templates to prepare nanocopper-nickel alloy (Cu-Ni/CNTs) composite materials. Experiments prove their electrochemical activity is superior to the pure alloy in alkaline solution, and the peak reaches maximum value when alloy is 20 wt%.

In this research, Silver—nickel alloy nanocomposites has been synthesized by reducing mixture solution of Ni2+, Ag+ with hydrazine hydrate as reducer and OP-10 as surfactant. Silver—nickel alloy nanocomposites were characterized by FT-IR, XRD, SEM. And the electrochemical properties of the samples were studied by cyclic voltammetry. Ag-Ni/PANI composites were prepared by in-situ synthesis and emulsion polymerization, and the effect of conduction on the conductivity was investigated including content of alloy. The detailed analysis of the synthesis conditions shows that the reduction takes place in alkaline environment and low-temperature is propitious to generate alloy solid-solution grain. Composites prepared by emulsion polymerization in acidic aqueous solutions synthesis of polyaniline shows higher conductivity than pure polymer, due to the strong interaction between alloy particles and doping PANI.

In this paper, multiwalled carbon nanotubes (MWCNTs)/epoxy resins (EP) composite was prepared by situ polymerization. MWCNTs/EP composites were prepared with different content of MWCNTs. The study of morphology and properties showed certain content of MWCNTs can well homogeneous dispersed in EP. Since of interface interaction between MWCNTs and EP, the glass transition temperature (Tg), strength and toughness of MWCNTs/EP composites were improved. Compared to the neat EP, composites prepared with 10 wt% MWCNTs showed 20 °C rising in Tg and nine orders of magnitude reduce in volume resistivity. The percolation thresholds between 4 wt% and 6 wt% are observed. Compared to the neat EP, composites prepared with 6 wt% MWCNTs showed with 83 % increase in tensile strength, 83 % increase in elastic modulus and 89 % increase in impact strength.

In this paper low molecular polyamide 651(PA651) is used as the curing agent of epoxy resin. The optimum curing conditions and dosage of the curing agent are obtained by DMA and FT-IR analysis. Based on the dynamic mechanical temperature spectra of samples test, the best curing conditions are room temperature 2 hours, 70°C 2 hours, 125°C 2.5 hours and 150°C 1 hours (RT / 2 h + 70 °C / 2 h +125°C / 2.5 h + 150 °C / 1 h). The best dosage of curing agent PA651 is 50 wt %. Since the analysis of Fourier Infrared spectral verified that epoxy groups react completely, the curing conditions are the best curing process.

A simple synthetic route to create Nickel nanoparticles/MWCNT composites (NiNPs/MWNTs) is reported. The process is concise, no additional surfactant or other reducing gas was employed. TEM, SEM, XRD and EDX were used to examine the morphology of the nickel particles. In this experiment, the hydrothermal method using ethylene glycol as a solvent has been well dispersed, uniform size and smaller particle size of the nickel nanoparticles with average size about 50 nm. By cyclic voltammetry test results show that with good electrical properties, Ni / MCNTs.

This paper presents a synthetic method of graphene load nickel nanoparticles composites. Hydrothermal process is simple and convenient way, neither surfactant is needed nor by products will exist serve hydrazine hydrate as reductant. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses were used to characterization the morphology of the graphene load nickel nanoparticles composites, and cyclic voltammetry (CV) was used to characterization the electrical properties of the composites. The results of XRD and FTIR show that the complexes were successfully synthesized by this method. Moreover, the good dispersibility and relatively uniform particle size of the complexes can be obviously observed from the SEM image. And the cyclic voltammetry curves exhibit good electrical properties of graphene load nickel nanoparticles composites. All the conclusions are based on the experimental results.

This essay describes the findings of generating the electrode composite of polyaniline/activated carbon fiber ( PANI/ACF) by repeatedly immersing eigenstate PANI into the solution of NMP and CHCl3 added with VC. A samples surface profile and structure were represented using SEM and FT-IR. Thereafter the composite was assembled into a super capacitor, electrochemical performances of which were then tested through cyclic voltammetry (CV). The result showed that the specific capacitance of this composite is up to 531.75F/g in the solution of 6 mol·L-1 KOH.

A mild and efficient approach for the reduction of graphene oxide by NaHTe is reported in this work. This reductant is of low toxicity and nonvolatile and it reduce GO to graphene at room temperature in 2h. X-ray diffraction results showed that NaHTe can reduce GO completely in shorter time, comparing with hydroxylamine. Furthermore, X-ray photoelectron spectroscopy also indicates the reduction of GO to grapheme.

An cost effective, and simple method of preparation of surface modified graphene has been described in this work. Graphene oxide (GO) was synthesized from flake graphite by following a modified Hummers’ method. In comparison with other strong reducing agents used in GO reduction, we found thioglycolic acid (TGA) has its unique advantages in forming stable water dispersion of reduced GO. Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analysis confirmed the successful reduction of GO to graphene. Scanning electron microscopy (SEM) images of the product confirm the presence of thin sheets.

Aniline monomer coated on the nanotubes in HCl solution was used to prepare a composite of multi-wall carbon nanotube/polyaniline (MWCNT/PANI) by in-situ polymerization. Multi-wall carbon nanotubes were treated by the mixed acid (HNO3:H2SO4in a ratio of 1:3). The content of MWCNT in the samples was 0-20 wt%. The nanocomposites were characterized by Thermogravimetric analysis (TGA), Fourier transform-infrared spectroscopy (FT-IR), Raman spectroscopy and scanning electron microscopy. The mechanical properties of the MWCNT/PANI nanocomposites were also measured. The results showed that the MWCNT was well dispersed in water after purification. Both FT-IR and Raman spectra illustrated the presence of MWCNT in the composites; the interaction between PANI and MWCNT was proved. The Young΄s modulus was 618MPa with 20wt% loading. The effects of treatment of MWCNT on the mechanical properties of MWCNT/PANI nanocomposites are discussed.

The purpose of this paper is to develop feasible composite electrodes with a long cycle life and large specific capacitance and to investigate optimal ratio between aniline and carbon aerogels (CA) materials. The characterization of the composite electrode materials was studied by using scanning electron microscopy (SEM), electrochemical impedance spectroscopy, cyclic voltammetry (CV) and the constant charge-discharge. The specific capacitance of the composite electrode materials, measured using cyclic voltammetry at scan rate of 1mV•s-1, was found to be 1139.66F•g-1. For a simple supercapcitor, the highest specific capacitance (127.53 F•g-1 at 30mA) is obtained at ratio between aniline and CA is 1:4.

It is reported that a pitch gradient is formed in a side chain cholesteric liquid crystalline polymer (ChLCP) through a novel method. Heating up the ChLCP within the temperature range of the cholesteric (Ch) phase leads to the first availability of its planar texture. Then, the ChLCP film with the planar texture is cooled down to its glassy (G) state in line with the temperature difference between the upper and the bottom substrates. The SEM image indicates clearly a pitch gradient perpendicular to the substrates, and the results of transmission spectra show that the reflective bandwidth of the ChLCP film with the pitch gradient is greatly broadened.

Two series of novel cholesteryl-containing H-bonded liquid crystals were prepared through facile self-assembly between cholesteryl isonicotinate (proton acceptor) exhibiting a monotropic cholesteric phase, and the 4-alkoxy-benzoic acid or 4-alkoxy cinnamic acid (proton donor). It was found that the increase of the conjugate length as well as the terminal length can contribute to enhance the interaction of molecules and thus significantly influenced the thermal behaviors of H-bonded LCs. The cholesteric reflection spectra of the induced mesogenic complexes were located in the visible region with the color tuneable thermo-sensitivity, which could be used for display application.

Two series of novel tolane-type liquid crystals (LCs) comprising of hydrogen-bonded organic acids were synthesized. The formation of dimerized H-bond LCs was confirmed by IR spectroscopy, and mesomorphic properties of the LCs were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). It was found that the end groups of the liquid crystals as well as the unsaturated rigid core had effect on the mesomorphic properties.

Purpose The purpose of this study is to investigate the associations of the x-ray repair cross-complementing 1 gene (XRCC1) single nucleotide polymorphisms (SNPs) Arg194Trp, Arg280His, and Arg399Gln with gastric cancer risk. Methods The PubMed, Embase, Cochrane Central Register of Controlled Trials, Google Scholar, CINAHL, International Bibliography of the Social Sciences, and Social Sciences Citation Index were searched. Two authors independently searched for relevant studies in any language from 1966 to Jan 2013. Results Seventeen studies with a total population of 10427 participants were identified. The results showed there were no associations of Arg399Gln polymorphism with gastric cancer, no matter in the co-dominant model, dominant model or recessive model. For Arg194Trp and Arg280His polymorphism, still no significant differences were found between control groups and GC groups in samples regardless of race. However, significant associations between Arg194Trp polymorphism and gastric cancer were found in Asian. The Asia with mutant genotype (Trp/Trp+Arg/Trp) had a higher risk of GC compared with the Asian with wild genotype (Arg/Arg). Conclusion Our meta-analysis indicates that genetic polymorphism of the XRCC1 Arg399Gln and Arg280His do not have an association with gastric cancer risk. However, for Arg194Trp polymorphism, mutant gene carriers had a higher GC risk in Asian.