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A novel ternary nanocomposite of nickel-manganese oxides/multi-walled carbon nanotubes (NMO/MWCNTs) coated with poly (3,4-ethylenedioxythiophene)(PEDOT) was prepared by chemical oxidation method. The filling of NMO particles inside MWCNTs and the uniform coating of NMO/MWCNTs with PEDOT intensified the capacitive behavior of MWCNTs. The lowest IR drop (0.1 V) and highest specific capacitance (SC) values of 526.55 F/g of NMO/MWCNTs/PEDOT imply it as highly efficient hybrid supercapacitor materials in 6 M KOH electrolyte.

Recent developments in nanotechnologies have helped to benchmark carbon nanotubes (CNTs) as one of the most studied nanomaterials. By taking advantages of CNTs extraordinary physical, chemical and electronic properties, a wide variety of applications has been proposed in various engineering fields. In this short review, the contribution of CNTs is addressed in terms of sustainable environment and green technologies perspective, such as waste water treatment, air pollution monitoring, biotechnologies, renewable energy technologies, supercapacitors and green nanocomposites. Consideration of CNTs for large scale application from the aspect of cost and potential hazards are also discussed. Based on the literature studied, CNTs pose a great potential as a promising material for application in various environmental fields.

This paper reports the synthesis and characterization of new ternary nanocomposites combining polyaniline (PANI), multiwalled carbon nanotubes (MWCNTs) and manganese dioxide (MnO2). MnO2 was successfully incorporated within the MWCNTs. In situ polymerization of aniline in the presence of MWCNTs–MnO2 was carried out to form PANI/MWCNT–MnO2 nanocomposites, which were characterized by UV–visible and Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy with energy-dispersive X-ray analysis, and transmission electron microscopy, as well as electrical conductivity measurements. The PANI/MWCNT-MnO2 nanocomposites showed enhanced electrical conductivity compared to neat PANI and PANI/MWCNTs without MnO2 addition.

TiO 2 coatings on glass foam substrates were produced by electrophoretic deposition (EPD) and sol–gel method with the aim to impart surface functional properties to glass foam such as antibacterial and photocatalytic effects. Starting with charged TiO 2 nanoparticles (21 nm) suspended in acetylacetone, EPD was shown to be a useful method to obtain TiO 2 coating on the glass foam substrates placed close to the deposition electrodes in the EPD cell. Best results were obtained by applying 25 V for 4 min and a subsequent thermal treatment (450 °C for 1 h). In the second approach, multilayer sol–gel TiO 2 coatings on glass foam were fabricated, which were heat-treated at 450 °C for 1 h to obtain pure anatase structure. Both techniques led to partially microcracked coatings which were however well adhered to the glass foam substrate (qualitatively assessed). The presence of microcracks was not considered to be a disadvantage as they increase the surface area of the coating, which is required to maximise the interaction of the titania layers with the environment for their antibacterial and photocatalytic function.

A considerable improvement in the quality of TiO2 coatings on multiwalled carbon nanotubes (MWNTs) was obtained by introducing a three-step purification and functionalization process which combines oxidation in air followed by sulfuric acid refluxes and reoxidation in air before synthesis of the TiO2 coating by the sol−gel method. A range of techniques, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-rays (EDX), X-ray diffraction (XRD), Raman spectroscopy, and thermal gravimetric analysis (TGA) were applied to characterize TiO2 coated MWNTs obtained by sol−gel. TEM results showed that the MWNTs were fully and homogeneously coated with TiO2 while SEM coupled with EDX confirmed the presence of a thick layer of TiO2 coating the MWNTs. XRD and Raman spectroscopy results revealed that the crystalline structure of TiO2 on the surface of MWNTs was anatase.

Recently, many studies have been reported about a variety of carbon materials in adsorbing hydrogen. Regarding that, hydrogen adsorption in different carbonaceous materials was investigated at room temperature, 298 K and three different pressures which were 6.5, 8.5 and 9.5 bar. Pressure drop of hydrogen was measured and the amount it adsorbed was calculated by using ideal gas law and it was presented in weight percent, wt.%. In this paper, the effect of a purification process on hydrogen adsorption was also discussed. Along with that, pretreatment also gave a major influence in hydrogen adsorption because it affected the adsorption behavior of the carbon nanotubes surfaces. The highest result obtained during this work was 0.195 wt.% for purified carbon nanotubes.

Supported-NiO catalysts were tested in the synthesis of carbon nanotubes and carbon nanofibers by catalytic decomposition of methane at 550 °C and 700 °C. Catalytic activity was characterized by the conversion levels of methane and the amount of carbons accumulated on the catalysts. Selectivity of carbon nanotubes and carbon nanofiber formation were determined using transmission electron microscopy (TEM). The catalytic performance of the supported-NiO catalysts and the types of filamentous carbons produced were discussed based on the X-ray diffraction (XRD) results and the TEM images of the used catalysts. The experimental results show that the catalytic performance of supported-NiO catalysts decreased in the order of NiO/SiO 2 > NiO/HZSM-5 > NiO/CeO 2 > NiO/Al 2 O 3 at both reaction temperatures. The structures of the carbons formed by decomposition of methane were dependent on the types of catalyst supports used and the reaction temperatures conducted. It was found that Al 2 O 3 was crucial to the dispersion of smaller NiO crystallites, which gave rise to the formation of multi-walled carbon nanotubes at the reaction temperature of 550 °C and a mixture of multi-walled carbon nanotubes and single-walled carbon nanotubes at 700 °C. Other than NiO/Al 2 O 3 catalyst, all the tested supported-NiO catalysts formed carbon nanofibers at 550 °C and multi-walled carbon nanotubes at 700 °C except for NiO/HZSM-5 catalyst, which grew carbon nanofibers at both 550 °C and 700 °C.

Catalyst reduction temperature was observed to affect the yield and diameter uniformity of carbon nanotubes (CNTs) produced on Co-Mo/Al2O3 catalysts. The results show that on the whole, the reduced catalysts gave higher carbon yield. The CNTs obtained from the unreduced catalyst and the catalysts reduced at 400, 550, and 700 °C had diameters of 9.0 ± 1.4, 11.0 ± 1.8, 11.2 ± 1.8, and 12.1 ± 2.7 nm, respectively, showing that an increase in catalyst reduction temperature produced a slightly larger average diameter and wider diameter distribution. Raman spectra further elucidate that better-graphitized CNTs were produced on the catalysts reduced with increasing reduction temperatures.

Novel material with peculiar properties can be obtained by introducing foreign materials into the inner cavity of carbon nanotubes. It has been suggested that the materials encapsulated into the hollow regions of carbon nanotubes could result in a significant change of the properties of these small particles, forming new hybrid composites with extraordinary properties. In this short communication, filling of carbon nanotubes with manganese oxide by wet chemical method is demonstrated. Transmission electron microscopy (TEM) result showed the hollow structure of carbon nanotubes were filled with manganese oxide. Energy dispersive X-rays (EDX) spectra elucidate the presence of manganese oxide in the filled carbon nanotubes whereas SEM result showed that manganese oxide is not crystallized at the outer surface of carbon nanotubes.

The effect of catalyst calcination temperature on the uniformity of carbon nanotubes (CNTs) diameter synthesized by the decomposition of methane was studied. The catalysts used were CoO–MoO/Al 2 O 3 without prior reduction in hydrogen. The results show that the catalyst calcination temperature greatly affects the uniformity of the diameter. The CNTs obtained from CoO–MoO/Al 2 O 3 catalysts, calcined at 300 °C, 450 °C, 600 °C, and 700 °C had diameters of 13.4 ± 8.4, 12.6 ± 5.1, 10.7 ± 3.2, and 9.0 ± 1.4 nm, respectively, showing that an increase in catalyst calcination temperature produces a smaller diameter and narrower diameter distribution. The catalyst calcined at 750 °C was inactive in methane decomposition. Transmission electron microscopy (TEM) studies showed that CNTs grown on the catalyst calcined at 700 °C were of uniform diameter and formed a dense interwoven covering. High-resolution TEM shows that these CNTs had walls of highly graphitized parallel graphenes.

GO biological process enrichment analyses of most differentially expressed genes between AG1 and AG3. Head of columns represents SAM gene lists used as ToppGene inputs. The ten first significant biological processes are displayed (cutoff p-value = 0.01). (PDF 45 kb)

Continuous GES analyses interpretation in function of ER status in the three age groups. (PDF 75 kb)

Number of GO enrichment terms (biological tree) in common between GES’s gene lists. (PDF 68 kb)

GES listing, methods and references. (PDF 114 kb)

Percentage of GO enrichment terms (biological tree) in common between GES’s gene lists, sorted in decreasing order. (PDF 99 kb)

Metastasis-free survival (MFS) and overall survival (OS) analyses. MFS: 2A1: whole cohort; 2A2: Caucasian cohort. OS: 2B1: whole cohort; 2B2: Caucasian cohort. (PDF 230 kb)

Number of genes in common between GES. (PDF 46 kb)

GES analyses differentiating AG1 and AG3 luminal B patients. AG1 > AG3 means that AG1 GES score is superior to AG3 GES score, and inversely. (PDF 57 kb)

GES scoring of breast cancer in function of age. Correlation matrices show Pearson correlation coefficients between continuous GES (red indicates a positive correlation; blue, a negative correlation) and dendrograms show mutual relationships of all signatures (scores were used for average-link hierarchical clustering using the Pearson correlation as a distance metric). 2A1: AG1, whole cohort; 2A2: AG2, whole cohort; 2A3: AG3 whole cohort; 2B1: AG1, Caucasian cohort; 2B2: AG2, Caucasian cohort; 2B3: AG3, Caucasian cohort. (PDF 1689 kb)

Direct decomposition of methane was carried out using a fixed-bed reactor at 700 °C for the production of CO x -free hydrogen and carbon nanofibers. The catalytic performance of NiO-M/SiO 2 catalysts (where M=AgO, CoO, CuO, FeO, MnO x and MoO) in methane decomposition was investigated. The experimental results indicate that among the tested catalysts, NiO/SiO 2 promoted with CuO give the highest hydrogen yield. In addition, the examination of the most suitable catalyst support, including Al 2 O 3 , CeO 2 , La 2 O 3 , SiO 2 , and TiO 2 , shows that the decomposition of methane over NiO-CuO favors SiO 2 support. Furthermore, the optimum ratio of NiO to CuO on SiO 2 support for methane decomposition was determined. The experimental results show that the optimum weight ratio of NiO to CuO fell at 8:2 (w/w) since the highest yield of hydrogen was obtained over this catalyst.

Decomposition of methane into carbon nanotubes over CoO catalysts supported on various catalyst supports at 550 °C and 700 °C was investigated. The effect of catalyst promoters on the supported CoO catalysts at 700 °C was also examined. Electron microscope observations showed that among the various catalyst supports tested, alumina was found to be the most appropriate for CoO that CoO/Al2O3 catalyst grew carbon nanotubes with significant hollow cores. Experimental results further revealed that introducing FeO into CoO/Al2O3 catalyst resulted in the formation of carbon nanotubes with thin wall structure. Introducing MoO into CoO/Al2O3 catalyst increased the carbon capacity and the selectivity of CoO/Al2O3 catalyst in growing better quality carbon nanotubes.

The decomposition of methane into carbon and hydrogen over 15 mol % MnOx/20 mol %NiO/TiO2 catalysts was investigated. The effects of catalyst synthesis and pretreatment of 15 mol % MnOx/20 mol % Ni...

Experiments were conducted in a fixed-bed catalytic reactor to study the decomposition of methane to hydrogen and carbon over 13 wt % Ni/TiO2-based catalyst. The variables include the volumetric fl...

© 2014 John Wiley & Sons, Inc. Substantial progress and breakthroughs have been achieved for nanomaterials because of their nanometer size. Carbon nanotubes (CNTs), a type of nanomaterial, have received considerable interest worldwide because of their application in clean water technologies. CNTs are seamless cylinder-shaped macromolecules with radii in the nanometer range and lengths of up to several micrometers. Given the modifiable surface properties of CNTs, they are favorable for various applications related to improving and producing clean water technologies. Therefore, the contribution of CNTs in producing clean water is critically assessed in this chapter. A brief introduction to CNTs is presented, and modifications of CNTs to improve their intrinsic properties are discussed. We subsequently discuss the potential application of CNTs in the form of particles and membranes in various water treatment applications. A lifecycle assessment of CNTs in association with their environmental impact is discussed at the end of this chapter.

A simple nickel oxide catalyst has been developed in synthesizing single-walled carbon nanotubes (SWNTs) at moderate temperature. The catalyst used in the experiment was without a preceding reduction in hydrogen flow. The synthesis of SWNTs was performed at a temperature of 700 °C, which represents a moderate reaction temperature. The presence of SWNTs on the catalyst was confirmed by transmission electron microscope (TEM) and Raman spectroscope. The Raman spectrum shows a strong intensity at the radial breathing mode, indicating that the occurrence of SWNTs was dominant. Raman data further reveals that the synthesized SWNTs had the diameters in the range from 0.58 to 2.02 nm.

Y-junction carbon nanotubes were grown by catalytic CVD of methane at 700 ∘ C on NiO–CuO–MoO(7:2:1) (w/w/w)/SiO 2 catalyst. For comparison, NiO–CuO(8:2) (w/w)/SiO 2 and NiO–MoO(8:2) (w/w)/SiO 2 catalysts were tested for carbon nanotube formation. TEM analysis indicates that no Y-junction structures were formed with the latter two catalysts. This finding elucidates why the addition of a small amount of MoO to NiO–CuO/SiO 2 catalyst is crucial for enhancing the formation of Y-junction carbon nanotubes.

Item does not contain fulltext Hydroxyapatite is a biocompatible material that is extensively used in the replacement and regeneration of bone material. In nature, nanostructured hydroxyapatite is the main component present in hard body tissues. Hence, the state of the art in nanotechnology can be exploited to synthesize nanophase hydroxyapatite that has similar properties with natural hydroxyapatite. Sustainable methods to mass-produce synthetic hydroxyapatite nanoparticles are being developed to meet the increasing demand for these materials and to further develop the progress made in hard tissue regeneration, especially for orthopedic and dental applications. This article reviews the current developments in nanophase hydroxyapatite through various manufacturing techniques and modifications.

This paper reports the properties of cellulose nanowhiskers as new potential biomaterials. Cellulose nanowhiskers were produced from coconut husk fibres using four different anions of ionic liquids: 1-butyl-3-mehtylimidzalium chloride, 1-butyl-3-mehtylimidzalium acetate, 1-butyl-3-mehtylimidzalium bromide and 1-butyl-3-mehtylimidzalium hexafluorophosphate. The coconut husk fibre was chemically pretreated before cellulose dissolution. Morphology of the fibres under scanning electron microscopy showed that chemical treatment reduced much of surface materials on the fibres strand. Fourier transform infrared spectroscopy analysis determined that the reduced material was mainly lignin and the collected gel from the dissolution process is cellulose. Using Zetasizer Nano ZS the smallest cellulose obtained was 2.715 nm in diameter which was produced using 1-butyl-3-methylimidazolium acetate. While high-resolution transmission electron microscopy determined the cellulose produced was in rod form. The best condition for cellulose dissolution for cellulose was obtained using 1-butyl-3-methylimidazolium acetate IL at 60°C stirred for 90 minutes with 0.0126 mass ratio of fibres to IL.

(2010). Below is the response to his comment. Biodegradable polymers have attracted many interests to replace non-renewable petroleum-based polymers because of their degradability. Carbon nanotubes (CNTs) have been widely used as fillers for biodegradable polymers creating nanocomposites with enhanced mechanical properties (Sitharaman

Energy and environment are major global issues inducing environmental pollution. Energy generation from conventional fossil fuels has been identified as the main culprit of environmental degradation from global warming effects, in addition to environmental pollution which arises from rapid industrialization and agricultural development. In order to address these issues, nanotechnology plays an essential role in revolutionizing the applications for energy conversion and storage, environmental monitoring, as well as green engineering of environmental friendly materials. Carbon nanotubes and their hybrid nanocomposites have received immense research attention for their potential applications in various fields due to their unique structural, electronic, and mechanical properties. Here, we review the applications of carbon nanotubes (i) in energy conversion and storage as in solar cells, fuel cells, hydrogen storage, lithium ion batteries, and electrochemical supercapacitors, (ii) in environmental monitoring and wastewater treatment as in the detection and removal of gas pollutants, pathogens, dyes, heavy metals, and pesticides, and (iii) in green nanocomposite design. Integration of carbon nanotubes in solar cells and fuel cells has increased the energy conversion efficiency of these energy conversion applications, which serve as the future sustainable energy sources. Carbon nanotubes doped with metal hydrides show high hydrogen storage capacity of around 6 wt% as a potential hydrogen storage medium. Carbon nanotubes nanocomposites have exhibited high energy capacity in lithium ion batteries and high specific capacitance in electrochemical supercapacitors, in addition to excellent cycle stability. High sensitivity and selectivity towards the detection of environmental pollutants is demonstrated by carbon nanotubes based sensors, as well as the anticipated potentials of carbon nanotubes as adsorbent to remove environmental pollutants, which show high adsorption capacity and good regeneration capability. Carbon nanotubes are employed as reinforcement material in green nanocomposites, which is advantageous in supplying the desired properties, in addition to the biodegradability. This paper presents an overview of the advantages imparted by carbon nanotubes in electrochemical devices of energy applications and green nanocomposites, as well as nanosensor and adsorbent for environmental protection.

A major weakness of current orthopedic implant materials, for instance sintered hydroxyapatite (HA), is that they exist as a hardened form, requiring the surgeon to fit the surgical site around an implant to the desired shape. This can cause an increase in bone loss, trauma to the surrounding tissue, and longer surgical time. A convenient alternative to harden bone filling materials are injectable bone substitutes (IBS). In this article, recent progress in the development and application of calcium phosphate (CP)-based composites use as IBS is reviewed. CP materials have been used widely for bone replacement because of their similarity to the mineral component of bone. The main limitation of bulk CP materials is their brittle nature and poor mechanical properties. There is significant effort to reinforce or improve the mechanical properties and injectability of calcium phosphate cement (CPC) and this review resumes different alternatives presented in this specialized literature.

A major weakness of current orthopedic implant materials, for instance sintered hydroxyapatite (HA), is that they exist as a hardened form, requiring the surgeon to fit the surgical site around an implant to the desired shape. This can cause an increase in bone loss, trauma to the surrounding tissue, and longer surgical time. A convenient alternative to harden bone filling materials are injectable bone substitutes (IBS). In this article, recent progress in the development and application of calcium phosphate (CP)-based composites use as IBS is reviewed. CP materials have been used widely for bone replacement because of their similarity to the mineral component of bone. The main limitation of bulk CP materials is their brittle nature and poor mechanical properties. There is significant effort to reinforce or improve the mechanical properties and injectability of calcium phosphate cement (CPC) and this review resumes different alternatives presented in this specialized literature.

A number of catalysts prepared from transition metals such as copper (Cu), iron (Fe), nickel (Ni), cobalt (Co) and manganese (Mn) on TiO 2 support were tested for the decomposition of methane into hydrogen and carbon. These catalysts were used in the experiments without any pretreatment. The experimental results show that the activities of the metal-TiO 2 catalysts decreased in the order of NiO/TiO 2 > CoO/TiO 2 > MnO x /TiO 2 ≃ FeO/TiO 2 ≃ CuO/TiO 2 . NiO/TiO 2 catalyst exhibited extremely high initial activity in the decomposition of methane. The optimum NiO doping on TiO 2 for the decomposition of methane were obtained at 20mol% NiO. The effective promoters for the catalyst was investigated using 15mol%M/20mol%NiO/Ti02 catalysts (where M = MnO x , FeO, CoO and CuO). 15mol%MnO x /20mol%NiO/TiO 2 was found to be an effective bimetallic catalyst for the catalytic decomposition of methane into hydrogen and carbon, giving higher catalytic activity, attractive carbon nanotube formed as well as longer catalytic lifetime.