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... A good understanding of the piezoresistive behavior of carbon fiber is highly valuable in studying the processing-structure-property relationship of this very important engineering material. Up-to-date, there is still a lack of agreement on the physical origin of the unique modulus-dependent piezoresistivity for carbon fibers. In the present work, an experimental and theoretical modeling combined ...
carbon; carbon dioxide; carbon nanotubes, etc ; aerosols; cutting; dry deposition; gases; Show all 7 Subjects
Abstract:
... Uniform ultra-short (<100 nm) single-walled carbon nanotubes (SWCNTs) with properties of rich chemistry, high dispersity and easy manipulation, are of great importance for constructing novel nano-structures and highly integrated miniature devices. Herein, we report a recent breakthrough in cutting long SWCNTs into uniform ultra-short segments in gas-phase using CO2 as a ‘blade.’ SWCNTs synthesized ...
carbon; carbon markets, etc ; cities; emissions; models; China; Show all 6 Subjects
Abstract:
... “Kyoto Protocol” states that carbon market is one of three private emission-reduction instruments. Since 2013 China implemented carbon emission trading scheme (ETS) in seven provinces or cities. The purpose of this paper is to investigate whether the implementation of ETS can result in the Porter effect. Based on the Porter hypothesis theory, this study employs the difference-in-difference (DID) m ...
carbon; carbon nanotubes, etc ; models; polymers; sowing; temperature; Show all 6 Subjects
Abstract:
... Single atomistic chains of carbon – a.k.a. carbyne – are of great interest due to their attractive properties. One route of proposed synthesis is exploiting the interior of a carbon nanotube, enabling sufficient alignment and affable temperature conditions for chain growth. Here, we delineate the optimal conditions for growth by means of full atomistic modeling of sequential carbon reactions insid ...
carbon; carbon nanotubes, etc ; anisotropy; molecular models; quantum mechanics; Show all 5 Subjects
Abstract:
... Due to the inherent spatial and temporal limitations of atomistic modeling and the lack of efficient mesoscopic models, mesoscale simulation methods for guiding the development of super strong lightweight material systems comprising collapsed carbon nanotubes (CNTs) are currently missing. Here we establish a path for deriving ultra-coarse-grained mesoscopic distinct element method (mDEM) models di ...
carbon; carbon fibers, etc ; compression strength; gels; shear strength; spinning; Show all 6 Subjects
Abstract:
... It is widely believed that wet-spinning and dry-jet wet/gel spinning make carbon fibers (CFs) with grooved and smooth surfaces, respectively. Here, dry-jet gel spinning was further developed to fabricate CFs with tunable surface topographies from smooth surface to uniform grooves. It opens a new way to fabricate CFs with combined advantages including surface grooves, high extruding/taking-up speed ...
carbon; carbon dioxide, etc ; automation; coal; gases; gasification; porosity; probability; Show all 8 Subjects
Abstract:
... Here, a large-scale char atomistic structure (41,438 carbon atoms) and simple simulation approaches explored char gasification behavior for H2O and CO2 — comparing their mixture with one gas being passive (non-reactive) and the dual reactive mixture. Reactivity was captured through simplistic atomistic simulations via an automated sequence of gas diffusion, close-contact determination for gas (es) ...
carbon; carbon nanotubes, etc ; electrodes; films (materials); gold; guidelines; nanogold; Show all 7 Subjects
Abstract:
... We mapped the nanoscale reduction of resistivity and noise source activities induced by metallic single walled carbon nanotubes (m-SWCNTs) embedded in gold thin films. In this method, current and noise maps of m-SWCNTs/gold hybrid thin films were recorded using a conducting probe in contact with the surface, and the maps were utilized to estimate the nanoscale variation of resistivity (ρ) and the ...
... Similarity and heterogeneity analysis of price dynamics across the region provide experiences for China’s national carbon emission trading scheme. This study examines the dynamic behavior of carbon prices from the visibility graph network point of view, notably introducing the Jaccard coefficient to measure the similarity. By mapping daily carbon trading prices onto visibility graph networks, we a ...
... To decouple the economic growth and carbon emission has been considered imperative to promote low-carbon economy. Nevertheless, previous studies on decoupling analysis between economic growth and carbon emission were contextualized merely in individual countries rather than the globe, which are insufficient for developing the low-carbon economy as a global target. Carbon intensity (CI), carbon emi ...
carbon, etc ; electrical properties; nanomaterials; semiconductors; Show all 4 Subjects
Abstract:
... Electronic and transport properties of semiconductor materials are very important to electronic and optoelectronic devices. Here, we present theoretical predication on the band structures and transport properties of zigzag C3N nanoribbons (ZC3NNRs) and related Schottky junctions. The results show that pristine ZC3NNRs are ferromagnetic metal, while the H-passivated ZC3NNRs are either nonmagnetic s ...
carbon dioxide; carbon dioxide enrichment; carbon sequestration, etc ; Reynolds number; gases; hydrogen; palladium; prediction; rhenium; Show all 9 Subjects
Abstract:
... Membrane separation is a promising method to separate CO2 and H2 from hydrogen-rich gases. This simultaneously achieves H2 recovery and CO2 enrichment. The latter is conducive to subsequent carbon capture and storage, and thereby the development of negative emission technologies. In this study, single-, double-, triple-, and quadruple-tube systems with palladium (Pd) membranes and cross-flow confi ...
carbon; carbon dioxide; carbon markets, etc ; developed countries; economic structure; emissions; emissions factor; environmental policy; models; China; Show all 10 Subjects
Abstract:
... China’s leaders are increasingly committed to low-carbon economic development. Although China’s economy has dramatically transformed since the initiation of economic reforms in 1978, it is still structurally different from post-industrial, high-income countries, and economic reform is ongoing. At the same time, China is taking major steps towards regulating its carbon dioxide emissions. China is c ...
carbon; carbon dioxide; carbon footprint, etc ; biofuels; butanol; ethanol; greenhouse gas emissions; methanol; mixing; oils; pentanols; Show all 11 Subjects
Abstract:
... Mitigation of carbon footprints in compression ignition (CI) engines can be achieved using biofuels (carbon neutral and carbon dioxide (CO2) sequestration effects), with oxygenates and effective post-combustion capture systems. The present study focuses on the net reduction of CO2 emissions through the combination of karanja oil methyl ester (KOME), orange oil (ORG), oxygenates blended fuel and ze ...
... Carbon nanotube (CNT), as a recently emerged newfangled nanomaterial, has been applied in terahertz (THz) polarizer due to its anisotropic hyper-ordered orientation. Herein, we simply adhere two orthogonal CNT sheets to the both sides of dielectric subwavelength grating to form a compound structure (i.e. CNT@Grating). Due to the subwavelength integration and cavity modes, the CNT@Grating presents ...
carbon; carbon nanotubes, etc ; nanocomposites; polymers; Show all 4 Subjects
Abstract:
... Recent research on the interfacial characteristics of carbon nanotube-polymer nanocomposites is reviewed. The state of knowledge in the characteristics of the interface between the carbon nanotubes and the polymer matrix is presented. Emphasis is placed on the progress of the relationships between interfacial characteristics and nanocomposite properties. Research methodologies used in studying the ...
... An effective and flexible method for the generation of computational samples for mesoscopic modeling of anisotropic networks of carbon nanotube (CNT) bundles with various degrees of CNT alignment is developed and applied for investigation of structural self-organization of nanotubes into vertically aligned CNT forests and fibers. Structural characteristics of the computational samples, such as bun ...
carbon; carbon nanotubes; carbon tetrafluoride, etc ; Raman spectroscopy; X-ray photoelectron spectroscopy; adhesion; contact angle; moieties; radio waves; scanning electron microscopy; Show all 10 Subjects
Abstract:
... In this paper, vertical aligned carbon nanotube arrays (VACNTs) were modified by radio-frequency tetrafluoromethane (CF4) plasma for different times, and the corresponding adhesion performance of VACNTs was investigated. Scanning electron microscopy and Raman spectroscopy showed that the VACNTs remained intact alignment after CF4 plasma treatment, but the defects and amorphous carbon increased wit ...
carbon fibers, etc ; capacitance; electrochemistry; electrodes; electrons; graphene; Show all 6 Subjects
Abstract:
... The electric permittivity is a fundamental material property that affects electrical, electromagnetic and electrochemical applications. This work provides the first determination of the permittivity of continuous carbon fibers. The measurement is conducted along the fiber axis by capacitance measurement at 2 kHz using an LCR meter, with a dielectric film between specimen and electrode (necessary b ...
carbon, etc ; annealing; hydrogen; moieties; paramagnetism; semiconductors; Show all 6 Subjects
Abstract:
... Pristine graphdiyne (pGDY) with high quality was prepared by annealing as-prepared GDY in hydrogen, and its stacking style, bandgap and magnetism were studied. The results show that pGDY is ABC-stacked, has a direct bandgap of ca. 0.64 eV, and shows spin-half paramagnetism at 2 K which may result from the residual hydroxyl groups on the chains of GDY sheet. The hybrid functional calculations show ...