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Biochar-based composite phase change materials (PCMs) are gaining popularity in thermal energy storage (TES) applications. Organic PCMs derived from fatty acids are favored for their affordability and variable melting temperatures based on carbon chain length. Understanding the interaction between different carbon-length fatty acid PCMs and porous biochar is crucial for optimizing thermal performance. Thus, this study explored the interaction between PCMs of decanoic acid (DA) and octadecanoic acid (OA) with banana peel (BP) biochar. Experimental results showed that shorter carbon chain of DA enhanced thermal properties and surface compactness compared to OA. BP-DA had higher loading efficiency and PCMs ratio, resulting in superior thermal cycle endurance and latent heat ratio. The molecular dynamics suggest that longer carbon chains affect the mean square displacement (MSD) curves, reducing the self-diffusion coefficients of BP-DA. This is due to DA's high loading rate, which occupies more space within BP biochar structure, thus limiting its diffusion capacity. Enhanced hydrogen bonding constrained DA's thermal motion during phase transition, restricting atom mobility within BP. With temperature elevations, BP-DA exhibits lesser fractional free volume than BP-OA, due to lower molecular mass. This research highlights how carbon chain length influences composite PCMs performance, offering insights for efficient TES system design. [ABSTRACT FROM AUTHOR]

The transport properties of molecular devices based on carbon chains are systematically investigated using a combination of non-equilibrium Green's function (NEGF) and density functional theory (DFT) first-principle methods. In single-carbon-chain molecular devices, a distinct even–odd behavior of the current emerges, primarily influenced by the density of states (DOS) within the chain channel. Additionally, linear, monotonic currents exhibit Ohmic contact characteristics. In ladder-shaped carbon-chain molecular devices, a notable current stabilization behavior is observed, suggesting their potential utility as current stabilizers within circuits. We provide a comprehensive analysis of the transport properties of molecular devices featuring ladder-shaped carbon chains connecting benzene-ring molecules. The occurrence of negative differential resistance (NDR) in the low-bias voltage region is noted, with the possibility of manipulation by adjusting the position of the benzene-ring molecule. These findings offer a novel perspective on the potential applications of atom chains. [ABSTRACT FROM AUTHOR]

Metallization for contacts in organic electronic nanodevices is of great importance for their performance. A lot of effects can appear at the contact/organic interface and modify the contact parameters, such as contact resistance, adhesive strength, and bonding ability. For novel materials, it is important to study the interactions with metal atoms to develop a suitable technology for contacts, fulfilling to the greatest extent the above-mentioned parameters. A novel material is carbyne, which is still under intensive research because of its great potential in electronics, especially for sensing applications. However, the most appropriate metallization strategy for carbyne-based devices is still unknown, so the interactions between carbyne and metal films should be studied to more precisely direct the development of the metallization technology, and to form contacts that are not limiting factors for device performance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Synthetic Crystals is the property of Journal of Synthetic Crystals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the supply chain environment, the collection of carbon footprint data and quantitative descriptions is important for optimizing the related carbon footprint for products in order to find a low carbon production route for the products and to develop a low carbon supply chain. In this paper, by combining the life cycle method and the input-output method, a carbon footprint calculation model based on the discriminant factor is put forward. The three-phase electric meter was selected as an example. A carbon chain model was established in order to calculate the carbon footprint, which established a quantitative description for the low carbon supply chain and provided a new idea and method for the low carbonization of the supply chain. [ABSTRACT FROM AUTHOR]

Scheelite-type strontium tungstate (SrWO4) phosphor powders were successfully synthesized using strontium nitrate and tungstic acid as starting materials by a gamma-ray irradiation-assisted polyacrylamide gel route. The phase purity, structure, functional groups, surface morphology, chemical composition, colorimetric, optical and photoluminescence properties of SrWO4 phosphor powders were systematically studied by various testing instruments. The crystallite size of SrWO4 phosphor powders increases with the increasing of sintering temperature. The color, optical and photoluminescence properties of SrWO4 phosphor powders are strongly dependent on the sintering temperature, carbon chain and the distortion of tetrahedral [WO4] clusters. The fluorescence emission at (310Â nm, 338Â nm, 360Â nm and 400Â nm) and 465Â nm can be ascribed to the new energy level formed by a carbon chain, amorphous SrWO4 or oxygen vacancy, and the distortion of tetrahedral [WO4] clusters, respectively. [ABSTRACT FROM AUTHOR]

The optical properties and dynamics of transport of electron excitation and the ways of its relaxation in the supramolecular D-π-A complex on the basis of merocyanines have been investigated. There have been found two components in the transfer of charge: fast and slow, which correspond to different conformational states of the carbon chain in merocyanines. It was found that the main photoluminescence of the studied molecular solutions of merocyanines by its nature is similar to the exciplex luminescence, as a manifestation of resonant and charge transfer interaction in an excited state. The lifetime in this state is about 2000 ps. [ABSTRACT FROM AUTHOR]

An explicit solution for the vibration of a carbon chain inside carbon nanotubes (CNTs) was obtained using continuum modeling of the van der Waals (vdW) interactions between them. The effect of the initial tensile force and the amplitude of the carbon chain as well as the radii of the CNTs on the vibration frequency were analyzed in detail, respectively. Our analytical results show that the vibration frequency of the carbon chain in a (5,5) CNT could be around two orders of magnitude higher than that of an independent carbon chain without initial tensile force. For a given CNT radius, the vibration frequency nonlinearly increases with increasing amplitude and initial tensile force. The obtained analytical cohesive energy and vibration frequency are reasonable by comparison of present molecular dynamics (MD) simulations. These findings will be a great help towards understanding the vibration property of a nanowire in nanotubes, and designing nanoelectromechanical devices. [ABSTRACT FROM AUTHOR]

It is shown that the elongation to failure δ and ultimate tensile strength σ in polymers are related as σ(1 + δ) = s = const at the temperatures of non-Hookean entropy viscoelasticity. Different drawing from different initial states brings the structure of polymer to the limiting uniaxial structure with the same true stress of breaking carbon chains s . [ABSTRACT FROM AUTHOR]

The energetic stability, atomic and electronic structures of γ-graphyne and its derivatives (γ-GYs) with extended carbon chains were investigated as a function of chain length by density functional calculations in this work. The studied γ-GYs consist of hexagon carbon rings connected by linear chains with C atoms n = 0-22. We predict that the even-numbered C chains of γ-GYs consist of alternating single and triple C-C bonds (polyyne), energetically more stable than the odd-numbered C chains made of continuous C-C double bonds (polycumulene). The calculated electronic structures indicate that γ-GYs can be either metallic (odd n) or semiconductive (even n) depending on the parity of the number of C chain atoms. The semiconducting γ-GYs are predicted to have ~1.2 eV direct band gaps and 0.1-0.2 effective electron masses independent of the chain length. Thus introducing sp carbon atoms into sp2-based graphene provides a novel way to open up band gaps without doping and defects while maintaining small electron masses critical to good transport properties. [ABSTRACT FROM AUTHOR]

The wide application of water-soluble linear polyacrylamides (PAMs) can cause serious environmental pollution. Biological treatment of PAMs receives very limited efficiency due to their recalcitrance to the microbial degradation. Here, we show the bioelectrochemical system (BES) can be used as an effective strategy to improve the biodegradation efficiency of PAMs. A linear PAM with viscosity-average molecular weight of 5 × 10 was treated in the anodic chamber of BES reactor, and the change of PAM structure during the degradation process was investigated. The anodic bacteria in the BES demonstrated abilities to utilize the PAM as the sole carbon and nitrogen source to generate electricity. Both the anode-attached and planktonic bacteria contributed to the electricity generation, while the anode-attached community exhibited stronger electron transfer ability than the planktonic one. The closed-circuit and open-circuit operations of the BES reactor obtained chemical oxygen demand (COD) removal efficiencies of 32.5 and 7.4 %, respectively, implying the generation of bioelectricity could enhance the biodegradation of PAM. Structure analysis suggested the carbon chain of PAM was partially degraded in the BES, producing polymeric products with lower molecular weight. The microbial cleavage of the carbon chain was proposed to start from the 'head-to-head' linkages and end with the formation of ether bonds. [ABSTRACT FROM AUTHOR]

Electron transfer in the molecular complex donor-polymer-acceptor type was investigated. The carbon chain, which has two possible conformations (homogeneous and dimerized), was taken as polymer. The theoretical model, which described the electron transfer process in such type of the systems, was proposed. The probability of detection of the electron on the each subsequent unit, if originally was located on the first unit, was theoretically investigated. Two types of the electron transfer were revealed. [ABSTRACT FROM AUTHOR]

Addition of a small amount of heavy 1-olefin into a supercritical-phase or liquid-phase FT reaction medium could significantly promote the carbon-chain growth and greatly enhance the selectivity of waxy products, with increased CO conversion while suppressing methane selectivity. The phenomenon was not observed in the gas-phase reaction. [ABSTRACT FROM AUTHOR]