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Hexavalent chromium (VI) is a toxic form of chromium metal generally used in many industrial applications for its anticorrosive properties. Cr (VI) has been deemed to be a class-A human carcinogen. Among all the techniques available, adsorption is one of the most suitable techniques. The efficiency of the process depends on the adsorption medium. Although there are several adsorbents available, there is still huge scope to develop a number of adsorption media for the benefit of the common people. In this study, nanomaterial synthesised from Jawar stem (Agro-Waste) has been used as an adsorbent for removal of Cr (VI) from aqueous solution. The Jawar stem nanofibers have been synthesised using chemical vapour deposition technique (CVD). The characterisation of adsorbent was carried out using various analytical techniques like XRD, BET, SEM, TGA and FTIR. The adsorption capacity of Jawar stem nanofibers was found to be 76.10 m2 gm−1. The removal of hexavalent chromium was studied as a function of contact time, dosage of adsorbent and initial concentration of Chromium (VI). The applicability of Langmuir and Freundlich isotherms was tested. Freundlich isotherm was found to be most suitable for all adsorbent dosages. [ABSTRACT FROM AUTHOR]

Carbon nanofibers, recently recognized pollutants, have been heavily used among the nanomaterials in many industries. Due to the poor suspension-stability, carbon nanofibers tend to sediment at the bottom of waterbodies and hence can be consumed by the bottom-dwellers. The current investigation evaluates the impact of carbon nanofibers at concentrations between 0.1 and 10 mg L−1 on the common bottom dweller spiny loach Lepidocephalichthys thermalis inhabiting Indian rivers. Carbon nanofiber exposure elevated the activities of the hepatic antioxidant enzymes superoxide dismutase, catalase, peroxidase and glutathione S-transferase, as oxidative stress markers. The fish behaviour patterns were examined by testing the effect of carbon nanofibers on predator recognition ability using kairomones, conspecific alarm cues, and dietary cues. The carbon nanofiber-exposed fish showed a loss of predator-recognition abilities. The results collectively demonstrated the carbon nanofiber driven hepatic oxidative damage and impaired predator-recognition ability in L. thermalis. The investigation, first of its kind, highlights the toxic potential of the carbon nanofibers on benthic fishes. [ABSTRACT FROM AUTHOR]

The electrospinning technique was used to prepare nanofibers samples consisting of three groups, each group has a different polystyrene concentration (12, 14, 16 wt.%). Multiwalled carbon nanotubes were added to each group with four ratios to yield four samples comprising (polystyrene/MWCNT) constituents. The UV-Visible test was carried out to know how uniformly nanofibers and Mutli-walled carbon nanotubes were distributed in the polymeric nanofibers and their effect on the final nanofiber's properties through the absorption peaks. The morphological test used "Field Emission Scanning Electron Microscope". The results showed that; MWCNTS has a dominant effect on prepared nanofibers in the (12 wt.% Polystyrene) group, and both (PS, MWCNT) have a shared effect, highest steady absorption curves, and uniformly scattered radiation at (14 wt.% PS) group, and random results at (16 wt.% PS) group. From FESEM results we notice that increasing polymer concentration causes an increase in the nanofiber's diameter and beads formation chance increases at (12,16 wt.% PS) groups. In the group of (14 wt.% Polystyrene), it produces nanofibers with free beads and uniform distribution, the addition of MWCNT lowers the diameter of nanofibers much more and enhances the orientation, and improves their UV absorption, strength, and mechanical properties. [ABSTRACT FROM AUTHOR]

The influence of carbon nanofibers (CNFs) on carbon fiber (CF) reinforced polymer (CFRP) is investigated in this study. A program is developed to generate the finite element model (FEM) for the nanocomposites. The randomness of both CNFs and CF in CFRP is considered. The effects of volume fraction of CNFs and CFs, as well as interfacial strength are analyzed numerically. The improvement in strength and toughness of composites under different loading conditions is investigated. It shows that CNFs lead the redistribution of stress in the matrix, which releases stress concentration between CFs and polymer and increases the initial damage threshold. [ABSTRACT FROM AUTHOR]

An efficient method to increase specific strength of carbon fiber reinforced plastics (CFRP) by using cellulose nanofibers (CNFs) was developed. Eliminating a complex hydrophobic treatment of CNF by using aqueous electrodeposition solution (EDS) containing a polymer with epoxy group, the CFRP with CNF/resin layer was fabricated. The effects of the CNF/resin layer on the bending properties of CFRP were clarified by varying the weight fractions of CNF. The specific flexural rigidity and strength of the CFRP with CNF/resin layer were increased to approximately 3.5 times and 1.8 times those of the CFRP without CNF/resin layer, respectively. [ABSTRACT FROM AUTHOR]

Carbon nanofibers are promising green materials for sustainable technology within a wide range of applications including environment, energy, health and high-technology. Accordingly, drug adsorption is an important subject in connection with its environmental and pharmaceutical applications. This study aims to investigate the adsorption performance of carbon nanofibers in batch and fixed bed column processes. Carbon nanofibers were used as adsorbent to remove triflupromazine hdyrochloride from aqueous solutions. Adsorption kinetics were studied using Lagergren first order and Pseudo second order models. Intraparticle diffusion graph was plotted using kinetic data and showed that intraparticle diffusion is the single step controlling the adsorption rate. Experimental equilibrium data was modeled by using Langmuir and Freundlich equations and has a better fit to the Langmuir model. Triflupromazine adsorption on carbon nanofibers was found to be H-type according to Giles classification. The effect of temperature and the effect of pH on adsorption were studied to determine optimum adsorption conditions. Adsorption capacity of carbon nanofibers was decreased with increasing temperature due to the exothermic and physical nature of the process. Thermodynamic parameters confirmed the exothermic nature of the adsorption. Results showed the effective adsorption of drug molecules by carbon nanofibers. Maximum adsorption capacity was calculated as 165.41 mg/g at pH 9 using Langmuir equation. Modeling of the fixed bed column data was done by using Thomas model and Yoon–Nelson model. Results showed the important effect of the operating conditions on the removal performance of carbon nanofibers. Removal capacity was increased with an increase in the flow rate and the increase in the fixed bed length. [ABSTRACT FROM AUTHOR]

Polymeric nanocomposites of polystyrene nanofibers and multiwall carbon nanotubes and natural pigment were synthesized using electrospinning technique the polystyrene concentration was 12 wt.% and multiwall carbon nanotube was added by (0, 100, 140, 200 ppm), and natural pigment added by two drops (0.063 g) to the prepared solutions and many tests were carried out to the prepared solutions and the final samples. The solution tests included viscosity test by using cone-plate viscometer and surface tension test using du-nouy ring method. The nano textiles tests included the Fourier transform infrared spectroscope (FTIR) test, Field emission scanning electron microscopy (FESEM) test, contact angle test, and ultraviolet test to extract the energy bandgap using (tauc plot) method. The tests results showed that the viscosity increased by increasing the multiwall carbon nanotube and natural pigment and surface tension slightly increased at a high ratio of 200 ppm of multiwall carbon nanotube and natural pigment and physical type of reaction between the components were confirmed through FTIR, and the addition of multiwall carbon nanotube and natural pigment makes the fibers smoother and fewer beads formation and increase the multiwall carbon nanotube addition made the samples more hydrophobic and the charts of tauc plot show that increasing the MWCNT with natural pigment addition will increase the electrical sensitivity of the prepared samples in which the energy band gap dropped from 1.18 ev to 0.2 ev for the sample of Polystyrene/200 ppm MWCNT/natural pigment this is regarded as an indication of using it as a typical electrical sensor. [ABSTRACT FROM AUTHOR]

Carbon nanofibers (CNFs) with excellent conductivity and stability have become a promising material to design the strain sensing network. To date, however, the effect of the stacked structure of CNF membrane on the sensing performance has rarely been studied. In this work, we reported a high-performance sensor based on the cross-stacked aligned CNF membrane. The effects of cross-stacked structures on the sensing characteristics were systematically investigated. The flexible strain sensor could capture low detection limit (<0.1%) with a gauge factor (GF) of 4.24 and wide strain range up to 130%. The uniform GF value reached 2050 when the strain was in the range of 100–130%. In addition, the high linearity under 40% strain (>0.998), excellent durability and quick response time (<200 ms) were demonstrated. The excellent comprehensive performances were simultaneously obtained. The sensor could be used in extensive applications, such as monitoring body movements and distinguishing the track of writing. [ABSTRACT FROM AUTHOR]

In this study, conductive and transparent polycaprolactone (PCL)/carbon black (CB) nanofibers are produced by electrospinning. In order to investigate the effect of solvent system on the optoelectrical properties of PCL/CB nanofibers, the fibers are produced from two different solvent systems; namely, chloroform (CHL) and dimetyl formamid (DMF). For optoelectrical characterization, nanofibers are produced with different deposition times in the range of 1–10 minutes. Surface, optical, electrical and optoelectrical properties of the PCL/CB nanofibers are evaluated. Nanofibers produced from CHL solvent system results in non-uniform nanofibers with higher diameters. They also give a larger diameter distribution. On the other hand, nanofibers with uniform and smaller diameters are obtained from DMF system. UV-spectrophotometer analysis show that nanofiber mats produced from both solvent systems have similar optical transparencies. Lower sheet resistance values are obtained with the nanofiber mats produced from DMF system according to electrical characterizations. Higher Figure of Merit values are calculated for the nanofiber mats produced in DMF solvent system. Considering all the results, it can be concluded that PCL/CB nanofibers produced from DMF solvent system are better candidates compared to the nanofibers produced from CHL solvent system for optoelectrical applications. [ABSTRACT FROM AUTHOR]

CNFs-Bi2WO6 nanocomposite was synthesized by hydrothermal method. The physico-chemical characterization of samples was done by XRD, SEM-EDX, UV-DRS, and PL spectra. CNFs-Bi2WO6 nanocomposite has shown better photodegradation efficiency than pristine Bi2WO6 for Rhodamine B dye under visible light irradiation. The addition of Bi2WO6 to pure carbon nanofibers (CNFs) facilitated absorption of light as well as assisted in separation of electron-hole pairs which ultimately lead to superior photodegradation efficiency. The CNFs-Bi2WO6 nanocomposite displayed excellent photocatalytic efficiency under visible light for dye degradation, owing to the synergistic effect of CNFs and Bi2WO6 with excellent charge separation characteristics and suitable band gap energy. The CNFs-Bi2WO6 nanocomposite was also screened for antimicrobial potential against two bacterial strains and one pathogenic fungal strain Candida albicans. The fabricated CNFs demonstrated antimicrobial activity, which was fortified due to inclusion of Bi2WO6 nanoflakes. [ABSTRACT FROM AUTHOR]

Polystyrene is an important and commonly used synthetic thermoplastic polymer. This state-of-the-art review is an endeavor to describe the unique capabilities of polystyrene to form the high performance nanocomposite nanofibers. Different types of nanofillers have been introduced in polystyrene nanocomposite nanofibers such as carbon nanotube, graphene, nanoclay, and metal nanoparticles. Accordingly, the article introduces the categories of the polystyrene/carbon nanotube, polystyrene/graphene, polystyrene/nanoclay, and polystyrene/metal nanoparticle nanocomposites. The comprehensive deliberations on design, morphology, physical properties, and developments related to polystyrene nanocomposite nanofibers are presented. The nanocomposite characteristics have been considerably enhanced with the addition of the nanoparticles. High performance polystyrene based nanocomposite nanofibers was found to be related to the interactions between the matrix and the nanofillers. The polystyrene nanocomposite nanofibers have found applications for electromagnetic interference shielding, sensors, membranes, and drug delivery. [ABSTRACT FROM AUTHOR]

In recent times, carbon nanofibers (CNF) have been used extensively for the remediation of environment owing to their hollow layered organization, high specific surface area, and strong electrostatic interactions which formulate it as an appropriate adsorbent material. Metallic nanoparticles were blended onto its surface in order to engineer a novel metal-CNF nanocomposite. The study aimed the ultrasonic assisted adsorption of rhodamine B dye (RhB) and pesticide dichlorophenoxyacetic acid (2,4-D) out of aqueous matrix by using silver (Ag) and copper (Cu) based bimetallic composite (Ag-Cu/CNF) material. The synthesized nanocomposites were characterized for its crystalline analysis, textural characteristics, surface chemical bonding, and specific surface area. Ag-Cu/CNF illustrated superior adsorptive efficiency when compared with Ag/CNF and Cu/CNF. Adsorption equilibrium was studied by Freundlich and Langmuir isotherms. Evaluation of the data predicted that Langmuir model described the maximum fit toward equilibrium data with utmost adsorption efficiency of 201 mg/g and 112 mg/g for RhB and 2,4-D, respectively. Also, the comparison between adsorption aided by ultrasound, magnetic stirrer, and vortex shaker assisted methods revealed that sono-sorption is a proficient option for commencement of adsorption phenomenon due to convenient and facile diffusion. [ABSTRACT FROM AUTHOR]

In the present work, a novel nanofiber-based filter has been presented which is comprised of composite nanofibers of polyamide-66 and TiO2 nanoparticles (PA-66/TiO2) for trapping cement dust. The produced nanofibers under optimum conditions were characterised by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The effect of some important electrospinning process parameters on the obtained electrospun nanofibers including solution concentration, flow rate, voltage‚ tip to collector distance and the presence of salt was investigated. Studies showed that the solution concentration of 15 wt. % of PA-66 resulted in thinner and smother nanofibers than the other solution concentrations and also the average diameter of the electrospun nanofibers was decreased with increasing 1 wt. % salt to the polymer solution. The produced nanofiber-based filter can be applied for capturing cement dust with a good filtration efficiency of 97% for 3–500 nm particles and a quality factor in the range of 0.069–0.034 Pa−1 [ABSTRACT FROM AUTHOR]

The goal of this study was to evaluate the mechanical properties of an experimental composite resin filled with nylon-6 nanofibers (N6), nylon-6 nanofibers with multi-walled carbon nanotubes (N6-MWCN) or with pre-polymerized resin at different concentrations. The fillers/particles were obtained from nanofibers produced by electrospinning technique or from pre-polymerized composite resin. The fillers were distributed in the composite resin in four different mass fractions (2.5, 5.0, 10.0, and 20.0%), totaling 12 groups. The volumetric polymerization shrinkage (VPS), composite film thickness (CRFT), flexural strength (FS) and elastic (E) modulus of the composite resins were calculated. The data were evaluated using two-way ANOVA and Tukey test (p <.05). The interaction concentration*filler material was statistically significant for the VPS (p =.0008) and for FS (p =.0001). The smallest VPS was observed in 20% concentration without a difference to 10% for N6-MWCN particles. For FS, N6-MWCN in 2.5 and 5.0% presented the highest values (116.4 ± 9.32; 118.5 ± 7.72). Both factors (p =.0001) were significant for CRFT. Higher concentration (20%) showed a higher film thickness. E modulus was similar for all conditions, with p =.0590 for filler material and p =.3987 for concentration. The most indicated composite reinforcement in order to achieve suitable flexural strength with decreased polymerization shrinkage is the use of pre-polymerized composite-based material at a concentration of 20%. N6-MWCNT particles in 2.5 or 5% concentrations should be incorporated to produce a composite resin presenting adequate strength associated with reduced film thickness. [ABSTRACT FROM AUTHOR]

Antibacterial composite nanofibers have recently been widely applied in biomedical fields. The purpose of this study is to combine Polyamide66 (PA) with carbon nanotubes (CNTs) and Ag nanoparticles through electrospinning and the aqueous reduction method to synthesis Ag@CNT/PA composite nanofibers with excellent conductivity, antibacterial property and cytocompatibility. The morphology and structure of Ag@CNT/PA composite nanofibers were analyzed by a series of characterizations. Conductivity of Ag@CNT/PA composite nanofibers in wet state was measured using a four-probe resistance tester. The antibacterial activity of Ag@CNT/PA composite nanofibers was tested by inhibition zone method, and the MG-63 cells were used to detect the cytotoxicological effects of the composite nanofibers. The results show that the Ag nanoparticles (50–100 nm) are distributed uniformly on the surface of nanofibers. Conductivity of Ag@CNT/PA composite nanofibers reaches (9.918 ± 0.043) × 10−4 S mm−1, significantly higher than that of PA nanofibers ((1.486 ± 0.017) × 10−4 S mm−1). The Ag@CNT/PA composite fibers present good antibacterial activity against Escherichia coli and Staphylococcus aureus. Cell culture results show that the cell proliferation of Ag@CNT/PA composite nanofiber group seems no significant difference with PA nanofiber group (p > 0.05) at day 7. The Ag@CNT/PA composite nanofibers have no significant negative effects on MG-63 cells. [ABSTRACT FROM AUTHOR]

Copper oxide (CuO) nanofibers were successfully prepared by electrospinning and subsequent heat treatment. The chemical composition and morphology of the fibers were characterized by SEM, XRD and EDS. Beaded nanofibers with 100nm in diameter were prepared by simple electrospinning and calcining. The catalytic effect of CuO nanofibers on the combustion of ammonium perchlorate (AP) was investigated by TG and DTA. The results showed that the decomposition temperature of AP shifted by 101.9 °C to the low temperature and the catalytic efficiency was very high. This is mainly attributed to the higher surface to volume ratio of beaded copper oxide nanofibers compared with smooth nanofibers and spherical nanoparticles. The results suggest that the electrospinning of CuO nanofibers is a promising one-dimensional nanometer material in the field of propellant catalysis. [ABSTRACT FROM AUTHOR]

Iron oxide particle-decorated lignin-based carbon nanofibers (IO-LCNFs) were fabricated from organic mixtures containing acetic acid lignin (AAL) together with ferric acetylacetonate (Fe(acac)3) via electrospinning followed by stabilization in air and carbonization in nitrogen. After the addition of Fe(acac)3, IO-LCNFs showed different morphologies: Non-fused IO-LCNFs were obtained with diameters of 400–500 nm; iron oxide nanoparticles with diameters of 30–60 nm were exposed outside and well-distributed when sufficient amounts of Fe(acac)3were added. These carbon nanofibers were then used as electrode material for pseudocapacitor. It was found that the iron oxide particles enhanced the resulting electrochemical properties via reversible redox reactions. IO-LCNFs made from the composite nanofibers with mass ratio of AAL/Fe(acac)3of 80/20 [i.e., IO-LCNFs (80/20)] exhibited the highest specific capacitance, 72.1 F g−1, at current density of 500 mA g−1. [ABSTRACT FROM PUBLISHER]

In an evaluation of carbon nanotubes (CNTs) for the IARC Monograph 111, the Mechanisms Subgroup was tasked with assessing the strength of evidence on the potential carcinogenicity of CNTs in humans. The mechanistic evidence was considered to be not strong enough to alter the evaluations based on the animal data. In this paper, we provide an extended, in-depth examination of the in vivo and in vitro experimental studies according to current hypotheses on the carcinogenicity of inhaled particles and fibers. We cite additional studies of CNTs that were not available at the time of the IARC meeting in October 2014, and extend our evaluation to include carbon nanofibers (CNFs). Finally, we identify key data gaps and suggest research needs to reduce uncertainty. The focus of this review is on the cancer risk to workers exposed to airborne CNT or CNF during the production and use of these materials. The findings of this review, in general, affirm those of the original evaluation on the inadequate or limited evidence of carcinogenicity for most types of CNTs and CNFs at this time, and possible carcinogenicity of one type of CNT (MWCNT-7). The key evidence gaps to be filled by research include: investigation of possible associations between in vitro and early-stage in vivo events that may be predictive of lung cancer or mesothelioma, and systematic analysis of dose–response relationships across materials, including evaluation of the influence of physico-chemical properties and experimental factors on the observation of nonmalignant and malignant endpoints. [ABSTRACT FROM AUTHOR]

A novel platinum–palladium nanoparticle-decorated carbon nanofiber nanocomposite was greenly prepared by attaching the nanoparticles to the nanofibers for the preparation of glucose biosensors. The platinum–palladium bimetallic nanoparticle-modified carbon nanofiber nanocomposite was characterized by transmission electron microscopy, X-ray diffraction, cyclic voltammetry, and electrochemical impedance spectroscopy. The glucose biosensor was constructed by immobilizing glucose oxidase on the nanocomposite-modified glassy carbon electrode by cross-linking with glutaraldehyde. The resulting biosensor exhibited a good response to glucose with a wide linear range from 2.5 × 10−6to 1.3 × 10−2 M with a high sensitivity of 154.6 µA mM−1cm−2and a detection limit of 0.7 µM. This biosensor was shown to offer good accuracy, precision, and reproducibility. The determination of glucose in human serum by the modified electrode was in good agreement with standard values. The nanocomposite electrode offers a suitable platform for the determination of glucose. [ABSTRACT FROM AUTHOR]

Electrospun polyacrylonitrile (PAN) nanofibers were pre-oxidized under 1, 2, and 3 wt% of KMnO4aqueous solutions. Scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction and Raman spectroscopy were used to study the effect of KMnO4concentration on the structures and properties of PAN-based heat stabilized and carbonized electrospun nanofiber mats. In FT-IR spectra of the preoxidized samples a new peak at 2340 cm−1designated to MnO4–C=N conjugation was revealed. Chemical modification by KMnO4was used to decrease the average diameter, increase the Bragg spacing, and decrease the preferred orientation and the crystal size. According to the Raman spectra, the bandwidths of the G mode became wider in the cases of preoxidized samples, while the G mode intensities belonging to the crystalline regions were decreased. According to the TGA studies, the weight losses in the preoxidized samples were severe due to the permanganate attack. [ABSTRACT FROM PUBLISHER]

Carbon nanofibers were in-situ grown on graphite-felt, and then Ru was supported to synthesize Ru/CNFs/GF structured catalyst. The comparisons of pressure gradient and reaction results clearly indicated that the Ru/CNFs/GF structured catalyst was more proper than powdered Ru/CNFs catalyst for sorbitol hydrogenolysis in a trickle bed reactor. For the structured catalyst, increasing the linear velocities would increase the sorbitol conversion, but only slightly change the glycols selectivity, which was due to the intensified mass transfer. Nevertheless, increasing the thickness of the carbon nanofibers layer would significantly decrease the glycols selectivity, which was due to the increased diffusion distance for hydrogen and glycols in the mesopores of the carbon nanofibers layer. [ABSTRACT FROM PUBLISHER]

Raman spectroscopy is employed to study the high-pressure response of carbon nanofibers exhibiting a unique morphology of stacked, truncated conical graphene layers (cups) along the longitudinal fiber axis (stacked-cup carbon nanofibers). The pressure evolution of the observed Raman peaks is smooth and reversible, and their pressure coefficients suggest an intermediate structural morphology between graphite and multiwall carbon nanotubes. The pressure coefficients are similar to those exhibited by the pressure-induced collapsed structures of large-diameter nanofibers and macroscopic fibers, suggesting the enhanced size-related rigidity of the studied system. [ABSTRACT FROM AUTHOR]

The removal of methylene blue (MB), a cationic dye and orange II (OII), an anionic dye, from aqueous solution by using carbon nanomaterials as multiwalled carbon nanotubes (MWNTs) and carbon nanofibers (CNF) as adsorbents was studied in batch experiments. The effect of pH, temperature and surface modification of adsorbent on the removal of MB and OII was also investigated. The removals of OII and MB by adsorption on MWNT were maximum at pH 3.0 and pH 7.0, respectively. However, in the case CNF was employed as adsorbent, the optimum values of pH were 9.0 and 5.0 for OII and MB, respectively. Langmuir and Freundlich isotherms are applied to fit the adsorption data of both dyes. Equilibrium data were well described by the typical Langmuir adsorption isotherm. Overall, the study demonstrated that MWNTs and CNFs can effectively remove cationic and anionic dyes as MB and OII from aqueous solutions under these experimental conditions. [ABSTRACT FROM AUTHOR]

The addition of carbon nanofibers to a polymeric matrix is known to affect its mechanical and electrical properties, although the mechanisms responsible for the changes are not sufficiently understood. Particularly, there are currently no adequate predictive methods that allow the creation of knowledge-based structures tailored for specific electrical response. We have developed a method for predicting the electric and dielectric properties of nanofiber-reinforced polymer matrices based on the application of the graph theory and circuit laws. We consider the individual properties of the polymeric matrix and the complex nanofiber network (including fiber orientation, concentration, and size), under an applied external electric field, and from the analysis we obtain information such as perlocative pathways, breakdown voltage, and impedance of the overall system. Simulations for two-phase systems consisting of a dielectric matrix and randomly oriented nanofibers have shown that the concentration and the length of the fibers affect the properties. Increased concentrations or longer fibers both result in networks for which it is easier to establish conducting paths through breakdown mechanisms. [ABSTRACT FROM AUTHOR]

Rheological properties of carbon nanfiber/polypropylene composites were investigated. CNFs synthesized at 600°C were thermally modified at 2200°C. These CNFs with a curl/twisted morphology were incorporated into polypropylene (PP) by intensive mixing. The untreated CNF composites showed higher dynamic moduli, G' and G'', than the heat-treated CNF composites. Also, stress relaxation results indicated that untreated CNF composites were relaxed in a longer time than heat-treated CNF composites. These results support that the untreated CNF composites needed less CNFs to perform CNF-CNF network than the heat-treated CNF composites did. It is suggested that structural changes can be verified by rheological analyses. [ABSTRACT FROM AUTHOR]

We have successfully fabricated straight carbon nanofibers containing coiled carbon nanofibers by ethanol catalytic combustion technique. In our experiment, copper plate was employed as substrate, transition metal salt solution as catalyst precursor, and ethanol as carbon source. The morphology and microstructure of the obtained carbon nanostructures have been investigated and their growth mechanism has been discussed. [ABSTRACT FROM AUTHOR]

Carbon nanomaterials are in the forefront of research in a variety of chemical and physical disciplines. Of these, certain nanostructures seem to be suitable for the development of electrochemical biosensors. In particular carbon nanotubes, and carbon nanofibers have specific chemical and physical characteristics that lent them ideal for the development of biosensors with unique analytical characteristics. In particular, their conductivity, surface area, inherent and induced chemical functionalities, and biocompatibility provide the grounds for the development of a new era of electrochemical biosensors. In this review, we will examine the recent developments of biosensor design based on these new nanostructures. [ABSTRACT FROM AUTHOR]

Systematic investigations were carried out into the sorption of rare earth elements (REEs) on carbon nonofibers (CNFs) by inductively coupled plasma mass spectrometry (ICP-MS). The experimental parameters for preconcentration of REEs, such as pH, sample flow rate and volume, eluent concentration, and interfering ions on preconcentration of REEs have been examined in detail. The studied metal ions can be adsorbed quantitatively on CNFs in a pH range from 2.0 to 5.0, and then eluted completely with 0.5 mol l-1 HNO3. Based on the above facts, a novel method using a microcolumn packed with carbon nanofibers as an adsorption material was developed for the separation and preconcentration of REEs prior to their determination by ICP-MS. The proposed method has been successfully applied to the determination of light (La), medium (Eu and Gd) and heavy (Yb) rare earth elements in real sample with the recovery more than 90%. In order to validate this method, two certified reference materials of tea leaves (GBW 07605) and mussel (GBW 08571) were analyzed, and the determined values are in good agreement with the certified values. [ABSTRACT FROM AUTHOR]

Continuous and uniform Ni-Co-B coatings were successfully deposited onto carbon nanofibers via electroless plating. SEM images of the prepared Ni-Co-B coated carbon nanofibers were presented. The magnetic properties of the coated carbon nanofibers were investigated. The CoSO4/(CoSO4+NiSO4) ratio in the electroless bath has obvious influence on the coercivity and residual magnetic flux density of the Ni-Co-B coated carbon nanofibers. [ABSTRACT FROM AUTHOR]

It is very important to study the effects of various factors on synthesis of carbon nanomaterials for controlled synthesis, which plays a significant role in realizing desired nanostructures or nanodevices for applications. In this report, we employed iron nitrate, cobalt nitrate, nickel nitrate, iron chloride, cobalt chloride and nickel chloride as catalyst precursors, and studied the effects of catalyst precursors on carbon nanofibers that were synthesized by ethanol catalytic combustion process. The as-grown carbon deposits have been characterized by scanning electron microscopy and transmission electron microscopy for deep understanding. The experimental results suggested that the carbon deposits synthesized by employing iron salt, cobalt salt, and nickel salt as catalyst precursors had different unique characteristics, respectively. [ABSTRACT FROM AUTHOR]

Piran M, Vakilian S, Piran M, et al. I In vitro i fibroblast migration by sustained release of PDGF-BB loaded in chitosan nanoparticles incorporated in electrospun nanofibers for wound dressing applications. When the above article was first published online, the figure numbers were incorrectly referred in the text. [Extracted from the article]