The influence of tip sonication duration on the spectral characteristics of carbon single-walled nanotubes (SWNTs) in aqueous suspension with single-stranded DNA (ssDNA) has been studied by NIR luminescence, NIR absorption, and Raman spectroscopy. It was revealed that prolongation of sonication leads to weakening of the SWNT polymer coverage and appearance of additional defects on the nanotube ...

A central result in the space geometry of closed twisted ribbons is Călugăreanu’s theorem (also known as White’s formula, or the Călugăreanu-White-Fuller theorem). This enables the integer linking number of the two edges of the ribbon to be written as the sum of the ribbon twist (the rate of rotation of the ribbon about its axis) and its writhe. We show that twice the twist is the average, over...

We report in situ measurements of four-probe dc resistance ~R! and thermopower ~S! of Csand K-doped single-wall carbon nanotube ~SWNT! mats as a function of a doping and temperature ~T!. With increasing dopant exposure, the mat resistance has been found to first decrease and then increase, exhibiting a minimum for optimal Cs doping. In contrast, for K doping, the mat resistance decreased monoto...

Carbon nanodots (CDs) with a low cytotoxicity have been synthesized by one-step microwave-assisted pyrolysis of citric acid in the presence of various amine molecules. The primary amine molecules have been confirmed to serve dual roles as N-doping precursors and surface passivation agents, both of which considerably enhanced the fluorescence of the CDs.

• A simple and reliable technique was developed electrospinning fibers with a flat ribbon-like morphology. ribbon-based electrode layer shows increased surface to volume ratio. The showed 2x higher permeability 40x volumetric specific than commercial electrodes. proposed materials were validated in an operating cell shown outperform at low moderate current density. method for the preparation of...

Microwave absorbing property of composites containing Ag nanoparticles filled multiwalled carbon nanotube buckypaper (Ag-BP) has been investigated. Buckypaper doped with silver was prepared by direct dispersion and filtration method. From the low temperature resistivity measurement it was found that increasing doping level decreases the electrical conductivity of the buckypaper. 30 wt. % and 40...

Void-defect is a possible origin of ferromagnetic-like feature pure carbon material. Applying density functional theory to void-defect induced graphene-nano-ribbon (GNR), detailed relationship between multiple-spin-state and structure change was studied. An equilateral triangle an initial void having six electrons distorted isosceles by re-bonding atoms. Among spin-states Sz=0/2, 2/2, 4/2 6/2, ...

An innovative strategy for post-synthesis nitrogen-doping of mesoporous carbons (MCs) with high yields (>90%) at low temperatures (230-380 °C) by using a strong base, sodium amide (NaNH2), was developed. The as-prepared N-doped MCs exhibit a significantly enhanced CO2 adsorption performance in terms of capacity and selectivity when compared to their parent MCs.

Self-organized V-N co-doped TiO2 nanotube arrays (TNAs) with various doping amount were synthesized by anodizing in association with hydrothermal treatment. Impacts of V-N co-doping on the morphologies, phase structures, and photoelectrochemical properties of the TNAs films were thoroughly investigated. The co-doped TiO2 photocatalysts show remarkably enhanced photocatalytic activity for the CO...

A close to native structure of bulk biological specimens can be imaged by cryo-electron microscopy of vitreous sections (CEMOVIS). In some cases structural information can be combined with X-ray data leading to atomic resolution in situ. However, CEMOVIS is not routinely used. The two critical steps consist of producing a frozen section ribbon of a few millimeters in length and transferring the...