Unusual Enhancement in Intrinsic Thermal Conductivity of Multilayer Graphene by Tensile Strains.

Using the Boltzmann-Peierls equation for phonon transport approach with the inputs of interatomic force constants from the self-consistent charge density functional tight binding method, we calculate the room-temperature in-plane lattice thermal conductivities k of multilayer graphene (up to four layers) and graphite under different isotropic tensile strains. The calculated in-plane k of graphite, finite monolayer graphene and 3-layer graphene agree well with previous experiments. For unstrained graphene systems, both the intrinsic k and the extent of the diffusive transport regime present a drastic dimensional transition in going from monolayer to 2-layer graphene and thereafter a gradual transition to the graphite limit.

Field Deployable Chemical Redox Probe for Quantitative Characterization of Carboxymethylcellulose Modified Nano Zerovalent Iron.

Nano zerovalent iron synthesized with carboxymethylcelluose (CMC-nZVI) is among the leading formulations of nZVI currently used for in situ groundwater remediation. The main advantage of CMC-nZVI is that it forms stable suspensions, which are relatively mobile in porous media. Rapid contaminant reduction by CMC-nZVI is well documented, but the fate of the CMC-nZVI (including "aging" and "reductant demand") is not well characterized.

Rational molecular engineering of cyclopentadithiophene-bridged D-A-π-A sensitizers combining high photovoltaic efficiency with rapid dye adsorption.

Dye-sensitized solar cell (DSSC) is considered as a feasible route to the clean and renewable energy conversion technique. The commercial application requires further enhancements on photovoltaic efficiency and simplification on the device fabrication. For avoiding the unpreferable trade-off between photocurrent (JSC) and photovoltage (VOC), here we report the molecular engineering and comprehensive photovoltaic characterization of three cyclopentadithiophene-bridged D-A-π-A motif sensitizers with a change in donor group.

Enhancement in Kinetics of the Oxygen Reduction Reaction on a Nitrogen-Doped Carbon Catalyst by Introduction of Iron via Electrochemical Methods.

The iron (Fe) electrodeposition-electrochemical dissolution has been employed on nitrogen-doped carbon material (P-PI) prepared via multi-step pyrolysis of a polyimide precursor to achieve the introduction of Fe species, and its influence on the oxygen reduction reaction (ORR) is investigated by cyclic and rotating ring-disk electrode voltammetry in 0.5 M H2SO4. After the electrochemical treatment, the overpotential and H2O2 production percentage of ORR on the P-PI are decreased and the number of electrons transferred is increased in the meanwhile.

Thermal conductivity enhancement in thermal grease containing different CuO structures.

Different cupric oxide (CuO) structures have attracted intensive interest because of their promising applications in various fields. In this study, three kinds of CuO structures, namely, CuO microdisks, CuO nanoblocks, and CuO microspheres, are synthesized by solution-based synthetic methods. The morphologies and crystal structures of these CuO structures are characterized by field-emission scanning electron microscope and X-ray diffractometer, respectively.

Estimation of retired mobile phones generation in China: A comparative study on methodology.

Due to the rapid development of economy and technology, China has the biggest production and possession of mobile phones around the world. In general, mobile phones have relatively short life time because the majority of users replace their mobile phones frequently. Retired mobile phones represent the most valuable electrical and electronic equipment (EEE) in the main waste stream because of such characteristics as large quantity, high reuse/recovery value and fast replacement frequency.

A bi-functional device for self-powered electrochromic window and self-rechargeable transparent battery applications.

Electrochromic smart windows are regarded as a good choice for green buildings. However, conventional devices need external biases to operate, which causes additional energy consumption. Here we report a self-powered electrochromic window, which can be used as a self-rechargeable battery.

Hydrothermal decomposition of liquid crystal in subcritical water.

Treatment of liquid crystal has important significance for the environment protection and human health. This study proposed a hydrothermal process to decompose the liquid crystal of 4-octoxy-4'-cyanobiphenyl. Experiments were conducted with a 5.

Porous fluorine-doped γ-Fe2O3 hollow spheres: synthesis, growth mechanism, and their application in photocatalysis.

Porous fluorine-doped maghemite(γ-Fe2O3) hollow spheres have been prepared by facile route based on solvothermal reaction and sequential calcinations. The composition and morphology of the as-prepared samples were characterized by various techniques. The SEM and TEM results showed that the as-synthesized products exhibited a spherical morphology with porous hollow structures.

Enantioselective changes in oxidative stress and toxin release in Microcystis aeruginosa exposed to chiral herbicide diclofop acid.

Enantioselective oxidative stress and toxin release from Microcystis aeruginosa after exposure to the chiral herbicide diclofop acid were investigated. Racemic diclofop acid, R-diclofop acid and S-diclofop acid induced reactive oxygen species (ROS) generation, increased the concentration of malondialdehyde (MDA), enhanced the activity of superoxide dismutase (SOD) and triggered toxin release in M. aeruginosa to varying degrees.

Fabrication of graphene/polyaniline composite for high-performance supercapacitor electrode.

Composite films of graphene and polyaniline nanofibers are prepared by in situ polymerization of aniline monomer in graphene suspension. The morphology and microstructure of samples are examined by scanning electron microscopy (SEM), transition electron microscopy (TEM), and X-ray diffraction (XRD). Electrochemical performances are characterized by cyclic voltammetry (CV) and galvanostatic charge/discharge measurements.

Recovering lead from cathode ray tube funnel glass by mechano-chemical extraction in alkaline solution.

This study evaluates the efficiency of lead (Pb) extraction from cathode ray tube (CRT) funnel glass in strongly alkaline solution using mechanical activation in a ball mill as the chemical breakage and defects formed in the inner structures will contribute to the easy dissolution of the activated Pb glass. The combination of mechanical activation and a chemical leaching process in a single operation (mechano-chemical leaching) is more effective than the mechanical activation and subsequent chemical leaching. More than 97% of Pb in the CRT funnel glass can be extracted with a stirring ball mill leaching process in 5 M sodium hydroxide at 70°C.

Optimization of biodiesel production process from soybean oil using the sodium potassium tartrate doped zirconia catalyst under Microwave Chemical Reactor.

A solid base catalyst was prepared by the sodium potassium tartrate doped zirconia and microwave assisted transesterification of soybean oil was carried out for the production of biodiesel. It was found that the catalyst of 2.0(n(Na)/n(Zr)) and calcined at 600°C showed the optimum activity.

Suppressing effect of calcium-based waste on control of bromine flux during the pyrolysis of printed circuit boards.

The effect of calcium-based addition on the brominate flux during printed circuit board (PCB) pyrolysis was investigated. It was found that bromine (Br) can be effectively fixed in solid phase during PCB pyrolysis by adding calcium-based waste materials. Phenol and 4-ethylphenol are the major products of pyrolysis.

Self-assembled 3D porous flowerlike α-Fe2O3 hierarchical nanostructures: synthesis, growth mechanism, and their application in photocatalysis.

In this work, a facile route using a simple solvothermal reaction to synthesize 3D porous flowerlike hierarchical nanostructures (HNs) of α-Fe(2)O(3) without employing templates or matrices for self-assembly is presented. The morphology and compositional characteristics of the 3D HNs were investigated by various techniques. The 3D HNs composed of 2D nanopetals, were intercrossed with each other and constructed from nanobricks with a length of about 100 nm and a diameter of about 30 nm.

Highly Efficient Method for Preparing Homogeneous and Stable Colloids Containing Graphene Oxide.

Phase transfer method has been developed for preparing homogeneous and stable graphene oxide colloids. Graphene oxide nanosheets (GONs) were successfully transferred from water to n-octane after modification by oleylamine. Corrugation and scrolling exist dominantly in the modified GONs.

Discussion on the thermal conductivity enhancement of nanofluids.

Increasing interests have been paid to nanofluids because of the intriguing heat transfer enhancement performances presented by this kind of promising heat transfer media. We produced a series of nanofluids and measured their thermal conductivities. In this article, we discussed the measurements and the enhancements of the thermal conductivity of a variety of nanofluids.

Effect of tip shape on line edge roughness measurement based on atomic force microscopy.

Atomic force microscopy (AFM) is an important tool in line edge roughness (LER) measurements, where accuracy for line edge identification is influenced by the shape of the tip. In this article, the effect of tip shape on LER measurement based on AFM is studied theoretically. The formulas for calculating the distance between the measured and actual line edge of the sample are presented.

Photodegradation of Vocs by C_TiO2 nanoparticles produced by flame CVD process.

Carbon containing C_TiO2 nanoparticles with rutile mass fractions about 20%, carbon mass fractions from 0-22%, having normal size distributions with mean sizes from 24-62 nm are synthesized by the oxidation of TiCl4 in industrial propane/air diffusion flame. Photodegradation of VOCs of formaldehyde, benzene, toluene and methanol by the C_TiO2 nanoparticles have been investigated by using a tubular photoreactor with C_TiO2 thin films coated on the wall of the tubular reactor by a sedimentation method. Effects of effective thickness of C_TiO2 thin films from 60-150 nm, relative humidity from 8-100%, and initial concentration of VOCs loaded air stream from 0.

Enhanced thermal conductivities of nanofluids containing graphene oxide nanosheets.

Stable ethylene-glycol-based nanofluids containing graphene oxide nanosheets have been prepared. The measurements of thermal conductivity indicate that the nanofluids have substantially higher thermal conductivities than the base fluid. The thermal conductivity enhancement depends strongly on the volume fraction of graphene oxide nanosheets and increases with the increasing loading.

Geometry preserving projections algorithm for predicting membrane protein types.

Given a new uncharacterized protein sequence, a biologist may want to know whether it is a membrane protein or not? If it is, which membrane protein type it belongs to? Knowing the type of an uncharacterized membrane protein often provides useful clues for finding the biological function of the query protein, developing the computational methods to address these questions can be really helpful. In this study, a sequence encoding scheme based on combing pseudo position-specific score matrix (PsePSSM) and dipeptide composition (DC) is introduced to represent protein samples. However, this sequence encoding scheme would correspond to a very high dimensional feature vector.

Bioleaching of metals from printed wire boards by Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans and their mixture.

Bioleaching processes were used to mobilize metals from printed wire boards (PWBs). The bacteria Acidithiobacillus ferrooxidans (A. ferrooxidans) and Acidithiobacillus thiooxidans (A.

Synthesis and Characterization of Monodispersed Copper Colloids in Polar Solvents.

A chemical reduction method for preparing monodispersed pure-phase copper colloids in water and ethylene glycol has been reported. Owing to the reduction property of ethylene glycol, the reaction rate in ethylene glycol is higher than that in water. In addition, the amount of reducing agent can be reduced largely.

Toxicity of chiral pesticide Rac-metalaxyl and R-metalaxyl to Daphnia magna.

Chirality in pesticides has become a challenge because of enantiomers' different toxicities to non-target organisms. Acute and chronic toxicities of Rac-metalaxyl and R-metalaxyl to Daphnia magna were determined and compared. The 48-h LC50 for Rac- and R-metalaxyl to Daphnia magna were 51.

Enantioselective degradation of metalaxyl in anaerobic activated sewage sludge.

Enantioselective degradation occurs frequently for chiral pesticides in field matrices and under laboratory conditions. Metalaxyl is a chiral compound and important fungicide. In this study, the degradation of Rac- and R-metalaxyl under anaerobic conditions was studied.