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opencc-by-4.0Oct 2022View details →

Thermodynamics of double-walled carbon nanotubes

Thermodynamics of double-walled carbon nanotubes Junjie Chen Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China Contributor: Junjie Chen, ORCID: 0000-0002-5022-6863, E-mail address: koncjj@gmail.com   Thermodynamics deals with the transfer of energy from one place to another and from one form to another. The most important laws of thermodynamics are stated herein. The zeroth law of thermodynamics. When two systems are each in thermal equilibrium with a third system, the first two systems are in thermal equilibrium with each other. This property makes it meaningful to use thermometers as the third system and to define a temperature scale. The first law of thermodynamics. The change in a system's internal energy is equal to the difference between heat added to the system from its surroundings and work done by the system on its surroundings. The second law of thermodynamics. Heat does not flow spontaneously from a colder region to a hotter region, or, equivalently, heat at a given temperature cannot be converted entirely into work. Consequently, the entropy of a closed system, or heat energy per unit temperature, increases over time toward some maximum value. Thus, all closed systems tend toward an equilibrium state in which entropy is at a maximum and no energy is available to do useful work. The third law of thermodynamics. The entropy of a perfect crystal of an element in its most stable form tends to zero as the temperature approaches absolute zero. This allows an absolute scale for entropy to be established that, from a statistical point of view, determines the degree of randomness or disorder in a system. The laws of thermodynamics are deceptively simple to state, but they are far-reaching in their consequences. The first law is put into action by considering the flow of energy across the boundary separating a system from its surroundings. Consider the classic example of a gas enclosed in a cylinder with a movable piston. The walls of the cylinder act as the boundary separating the gas inside from the world outside, and the movable piston provides a mechanism for the gas to do work by expanding against the force holding the piston in place. If the gas does work as it expands, and absorbs heat from its surroundings through the walls of the cylinder, then this corresponds to a net flow of energy across the boundary to the surroundings. In order to conserve the total energy, there must be a counterbalancing change in the internal energy of the gas. From a formal mathematical point of view, the incremental change in the internal energy is an exact differential, while the corresponding incremental changes in heat and work are not, because the definite integrals of these quantities are path-dependent. These concepts can be used to great advantage in a precise mathematical formulation of thermodynamics. The science of thermodynamics provides a rich variety of formulas and techniques that allow the maximum possible amount of information to be extracted from a limited number of laboratory measurements of the properties of materials. However, as the thermodynamic state of a system depends on several variables, such as temperature, pressure, and volume, in practice it is necessary first to decide how many of these are independent and then to specify what variables are allowed to change while others are held constant. For this reason, the mathematical language of partial differential equations is indispensable to the further elucidation of the subject of thermodynamics. Of especially critical importance in the application of thermodynamics are the amounts of work required to make substances expand or contract and the amounts of heat required to change the temperature of substances. The first is determined by the equation of state of the substance and the second by its heat capacity. Once these physical properties have been fully characterized, they can be used to calculate other thermodynamic properties, such as the free energy of the substance under various conditions of temperature and pressure.

opencc-by-4.0Oct 2010View details →

Figure 3: The microscopy images fo neuronal cells generated by SWCNT (a) and MWCNT (b)-COMPARATIVE STUDY OF SINGLE- AND MULTI-WALL CARBON NANOTUBES WITH APPLICATION IN CEREBRAL ANEURYSM

Carbon nanotubes (CNTs) are nanometer-scale cylindrical graphitic struc- tures that exhibit extraordinary physical properties as determined by their structure [6]. Developing neural implants and the process of neuron regener- ation are extremely di±cult. Nerve cells require the right environment and the right growth factors at the right time to grow and proliferate. The elec- trical conductive properties of these nanotubes o®er the possibility of using it as a replacement to transmit and receive signals. The resulting 'hair like' conductive wires that incorporate the properties of electrodes, permeable mi- cro°uidic conduits and the porosity of the CNTs was found to promote cell growth, migration and proliferation. The bridging consists either of an axon or bundles of axons and dendrites. In some cases the bridge is covered with clusters of cells [7]. These bridges form very e±ciently over quartz surfaces which are apparently very poor surfaces for cell attachment. Fig. 2 shows the evolution of a network generated by SWCNT and MWCNT. The data show that cells ¯rst aggregate at the NT islands. As they complete this step axons and dendrites begin to form and to build connections. Also, has been observed for MWCNT higher connections than for SWCNT, Figure 3.

opencc-by-4.0Jan 2018View details →

Figure 2: The microscopy images fo neuronal cells control (a) generated by MWCNT (b) and SWCNT (c)-COMPARATIVE STUDY OF SINGLE- AND MULTI-WALL CARBON NANOTUBES WITH APPLICATION IN CEREBRAL ANEURYSM

Fig. 2 shows the evolution of a network generated by SWCNT and MWCNT. The data show that cells ¯rst aggregate at the NT islands. As they complete this step axons and dendrites begin to form and to build connections.

opencc-by-4.0Oct 2010View details →

Figure 1: The structure of CNT-COMPARATIVE STUDY OF SINGLE- AND MULTI-WALL CARBON NANOTUBES WITH APPLICATION IN CEREBRAL ANEURYSM

Carbon nanotubes (CNTs) are nanometer-scale cylindrical graphitic struc- tures that exhibit extraordinary physical properties as determined by their structure [6]. Developing neural implants and the process of neuron regener- ation are extremely difcult. Nerve cells require the right environment and the right growth factors at the right time to grow and proliferate. The elec- trical conductive properties of these nanotubes o®er the possibility of using it as a replacement to transmit and receive signals. The resulting 'hair like' conductive wires that incorporate the properties of electrodes, permeable mi- cro°uidic conduits and the porosity of the CNTs was found to promote cell growth, migration and proliferation. The bridging consists either of an axon or bundles of axons and dendrites. In some cases the bridge is covered with clusters of cells [7]. These bridges form very e±ciently over quartz surfaces which are apparently very poor surfaces for cell attachment.

opencc-by-4.0May 2024View details →

Charge-Selective Photocatalytic Degradation of Organic Dyes using Halloysite Nanotubes

This study explores the use of Halloysite NanoTubes (HNTs) as photocatalysts capable of decomposing organic dyes under exposure to visible or ultraviolet light. We observe that the extent of RhB photocatalytic degradation in 100 min in the presence of the HNTs is ~4 times higher compared to that of bare RhB. Moreover, under optimized conditions, the as-extracted photodegradation rate of RhB (~0.0022 /min) is comparable to that of the previously reported work on the photodegradation of RhB in the presence of tubular nanostructures. A parallel effect is observed for anionic Coumarin photodegradation, albeit less efficiently. By leveraging the unique properties of HNTs, a family of naturally occurring nanotube structures, this research offers valuable insights for optimizing photocatalytic systems in the pursuit of effective and eco-friendly solutions for environmental remediation.

opencc-by-4.0Jun 2024View details →

Appendix A. Supplementary material for: Water-like thermal conductivity of ionanofluids containing high aspect ratio multi-walled carbon nanotubes and 1-ethyl-3-methylimidazolium-based ionic liquids with cyano-functionalized anions

Experimental data in numerical form for INFs composed of CNTs and [Emim]-based ILs with cyano-functionalized anions: density (Table S1), viscosity (Tables S2–S5), thermal conductivity (Tables S6, S7), and ANOVA analysis (Table S8).

opencc-by-4.0Aug 2021View details →

(DATASET) (10,0) carbon nanotubes functionalized with carboxyl and hydroxyl organic groups

Starting from a (10,0) carbon nanotube, 10 000 structures where randomly generated for both functionalizations (carboxyl, -COOH, and hydroxyl, -OH) and for 5 concentrations of the surface being funcionalized (5%, 10%, 15%, 20% and 25%). Then, the entropy of all system was calculated. The structures with highest entropy on each group/percentage where selected as representative of each functionalization. Here are the structures of functionalized (10,0) carbon nanotubes in MOL2 and XYZ formats. These systems were used in the following publications: <ul> <li>M.S. Ribeiro, A.L. Pascoini, W.G. Knupp, I. Camps. Effects of surface functionalization on the electronic and structural properties of carbon nanotubes: A computational approach. Applied Surface Science 426 (2017) 781–787. DOI: <a href="http://dx.doi.org/10.1016/j.apsusc.2017.07.162">10.1016/j.apsusc.2017.07.162</a></li> <li>W.G. Knupp, M.S. Ribeiro, M. Mir, I. Camps. Dynamics of hydroxyapatite and carbon nanotubes interaction. Applied Surface Science 495 (2019) 143493. DOI: <a href="https://doi.org/10.1016/j.apsusc.2019.07.235">10.1016/j.apsusc.2019.07.235</a></li> </ul>

opencc-by-4.0Aug 2021View details →

(VIDEOS) Dynamics of hydroxyapatite and carbon nanotubes interacting

These files correspond to the dynamics results for all the structures studied in the paper: <ul> <li>W.G. Knupp, M.S. Ribeiro, M. Mir, I. Camps. Dynamics of hydroxyapatite and carbon nanotubes interaction. Applied Surface Science 495 (2019) 143493. DOI: <a href="https://doi.org/10.1016/j.apsusc.2019.07.235">10.1016/j.apsusc.2019.07.235</a></li> </ul> The nomenclature to identify the systems is: <ul> <li>HAP, for hydroxyapatite.</li> <li>CNT, for pristine carbon nanotube.</li> <li>HAP+CNT, for the complex hydroxyapatite interacting with pristine carbon nanotube.</li> <li>HAP+CNTOHx, for hydroxyapatite interacting with -OH functionalized carbon nanotube.</li> <li>HAP+CNTCOOHx, for hydroxyapatite interacting with -COOH functionalized carbon nanotube.</li> <li>x = 5%, 10%, 15%, 20%, 25% represents the concentration of -OH or -COOH, respectively.</li> </ul>

opencc-by-4.0May 2023View details →

Data repository for manuscript "Contacting individual graphene nanoribbons using carbon nanotube electrodes"

This is the raw data for the manuscript "Contacting individual graphene nanoribbons using carbon nanotube electrodes”.

ClinicalTrials.gov40/100

Evaluation of a Carbon Nanotube Enabled Solid-State Head CT

ClinicalTrials.gov study NCT04495634. IPD Sharing: YES. Countries: 1. Publications: 0.

controlledIPD-YESFeb 2026View details →

opencc-by-4.0Dec 2020View details →

DNA methylation following long-term pulmonary multi-walled carbon nanotubes exposure in mice

Whole Genome Bisulphite Sequencing (WGBS) experiment to assess DNA methylation patterns in mice lungs 56 days after exposure to Multi-Walled Carbon NanoTubes (MWCNTs). The doses of MWCNTs used in this experiment were 0, 40 or 80 μg/mouse. In this record, we provide WGBS coverage files along with bedgraph files.

opencc-by-4.0Oct 2023View details →

Grid-type transparent conductive thin films of carbon nanotubes as capacitive touch sensors

This dataset contains the measurement data for figures (graphs) published in journal article:Grid-type transparent conductive thin films of carbon nanotubes as capacitive touch sensorsby Ronja Valasma, Eva Bozo, Olli Pitkänen, Topias Järvinen, Aron Dombovari, Melinda Mohl, Gabriela Simone Lorite, Janos Kiss, Zoltan Konya and Krisztian KordasPublished 11 May 2020 • © 2020 The Author(s). Published by IOP Publishing LtdNanotechnology, Volume 31, Number 30Citation:  Ronja Valasma et al 2020 Nanotechnology 31 305303DOI 10.1088/1361-6528/ab8590

opencc-by-4.0Feb 2022View details →

Nanotubes from the Misfit Layered Compound (SmS)1.19TaS2: Atomic Structure, Charge Transfer, and Electrical Properties_experimental dataset

This dataset contains the raw experimental data for the Sreedhara et al., Nanotubes from the Misfit Layered Compound (SmS)1.19TaS2: Atomic Structure, Charge Transfer, and Electrical Properties, Chem. Mater. 2022, 34, 4, 1838–1853

opencc-zeroMay 2024View details →

Data from: Nanotube structure of AsPS4–xSex (x = 0, 1)

Single-wall nanotubes of isostructural AsPS4−xSex (x = 0, 1) are grown from solid-state reaction of stoichiometric amounts of the elements. The structure of AsPS4 was determined using single-crystal X-ray diffraction and refined in space group P1. The infinite, single-walled AsPS4 nanotubes have an outer diameter of ≈1.1 nm and are built of corner-sharing PS4 tetrahedra and AsS3 trigonal pyramids. Each nanotube is nearly hexagonal, but the ≈3.4 Å distance between S atoms on adjacent nanotubes allows them to easily slide past one another, resulting in the loss of long-range order. Substituting S with Se disrupted the crystallization of the nanotubes, resulting in amorphous products that precluded the determination of the structure for AsPS3Se. 31P solid-state NMR spectroscopy indicated a single unique tetrahedral P environment in AsPS4 and five different P environments all with different degrees of Se substitution in AsPS3Se. Optical absorption spectroscopy revealed an energy band gap of 2.7 to 2.4 eV for AsPS4 and AsPS3Se, respectively. Individual AsPS4 microfibers showed a bulk conductivity of 3.2 × 10−6 S/cm and a negative photoconductivity effect under the illumination of light (3.06 eV) in ambient conditions. Thus, intrinsic conductivity originates from hopping through empty trap states along the length of the AsPS4 nanotubes.

opencc-by-4.0May 2024View details →

Transmission electron microscopy (TEM) images of multiwalled carbon nanotubes (MWCNT) detached from polycarbonate (PC) composites

Transmission electron microscopy (TEM) images of multiwalled carbon nanotubes (MWCNT) detached from polycarbonate (PC) composites to determine the MWCNT length distribution. Two sample series of TEM images are included. One based on PC type Makrolon® 2600 and one based on PC type Lexan 141R. The TEM images were taken by Mrs Manuela Heber and the measurement of the MWCNT lengths was carried out by Mrs Manuela  Heber and <a href="https://www.ipfdd.de/en/organization/organization-chart/personal-homepages/dr-beate-krause/">Mrs. Dr. Beate Krause</a> (both members of Leibniz-Institut für Polymerforschung Dresden e.V. (<a href="https://www.ipfdd.de/en/home/">IPF</a>)). The results of these measurements are presented in the following publication:  Petra Pötschke, Tobias Villmow, Beate Krause and Bernd Kretzschmar, Influence of Twin-screw Extrusion Conditions on MWCNT Length and Dispersion and Resulting Electrical and Mechanical Properties of Polycarbonate Composites, polymers 2024, 16(19), 2694. <a href="https://doi.org/10.3390/polym16192694">https://doi.org/10.3390/polym16192694</a>

opencc-by-4.0Jul 2024View details →

Transparent TiO2 nanotubes supporting silver sulfide for photoelectrochemical water splitting

The following dataset contains research data that is the basis of the research article: "Transparent TiO2 nanotubes supporting silver sulfide for photoelectrochemical water splitting" Contents of the package are the following: a) Experimental results of impedance spectra recorded for fTiNT and gTiNT b) Experimental results of UV-vis absorbance for Ag2S-coated and non-coated fTiNT, and gTiNT  c) Cyclic voltammetry carried out in 0.5 M Na2SO4 and Raman spectra for 25-Ag2S/gTiNT electrode  d) Cyclic voltammetry carried out in 0.1 M NaOH and Raman spectra for 45-Ag2S/gTiNT electrode

opencc-by-4.0Jul 2019View details →

Supporting data for "Cellulose separators with integrated carbon nanotube interlayers for lithium-sulfur batteries: an investigation into the complex interplay between cell components"

This is the dataset of electrochemical experiments for our publication "Cellulose separators with integrated carbon nanotube interlayers for lithium-sulfur batteries: an investigation into the complex interplay between cell components". This archive contains the raw data and scripts written in R used in the analysis and presentation of the results in this manuscript. Abstract for the manuscript: This work aims to address two major roadblocks in the development of lithium-sulfur (Li-S) batteries: the inefficient deposition of Li on the metallic Li electrode and the parasitic “polysulfide redox shuttle”. These roadblocks are here approached, respectively, by the combination of a cellulose separator with a cathode-facing conductive porous carbon interlayer, based on their previously reported individual benefits. The cellulose separator increases cycle life by 33%, and the interlayer by a further 25%, in test cells with positive electrodes with practically relevant specifications and a relatively low electrolyte/sulfur (E/S) ratio. Despite the prolonged cycle life, the combination of the interlayer and cellulose separator increases the polysulfide shuttle current, leading to reduced Coulombic efficiency. Based on XPS analyses, the latter is ascribed to a change in the composition of the solid electrolyte interphase (SEI) on Li. Meanwhile, electrolyte decomposition is found to be slower in cells with cellulose-based separators, which explains their longer cycle life. These counterintuitive observations demonstrate the complicated interactions between the cell components in the Li-S system and how strategies aiming to mitigate one unwanted process may exacerbate another. This study demonstrates the value of a holistic approach to the development of Li-S chemistry. Manuscript preprint <a href="http://dx.doi.org/10.26434/chemrxiv.8835728">available at ChemRxiv</a> (pending approval as of 9/7/19).

opencc-zeroDec 2022View details →

Data for: Simultaneously enhanced tenacity, rupture work, and thermal conductivity of carbon nanotubes fibers by raising effective tube portion

Although individual carbon nanotubes (CNTs) are superior as constituents to polymer chains, the mechanical and thermal properties of CNT fibers (CNTFs) remain inferior to synthetic fibers due to the failure of embedding CNTs effectively in superstructures. Conventional techniques resulted in a mild improvement of target properties while degrading others. Here, a Double-Drawing technique is developed to rearrange the constituent CNTs in both mesoscale and nanoscale morphology. Consequently, the mechanical and thermal properties of the resulting CNTFs can simultaneously reach their highest performances with specific strength ~3.30 N/tex (4.60 GPa), work of rupture ~70 J/g, and thermal conductivity ~354 W/m/K, despite starting from low-crystallinity materials (IG:ID~5). The processed CNTFs are more versatile than comparable carbon fiber, Zylon and Dyneema. Based on evidence of load transfer efficiency on individual CNTs measured with In-Situ-Stretching-Raman, we find the main contributors to property enhancements are the increasing of the effective tube contribution, in addition to the known optimization on CNTs alignment and stacking.

opencc-zeroJun 2023View details →

Photoelectrochemical performance of BiOI/TiO2 Nanotube Arrays (TNAs) p-n heterojunction synthesized by SILAR-ultrasonication-assisted methods

In order to extend the visible region activity of titania nanotube array (TNAs) films, the Successive Ionic Layer Adsorption and Reaction (SILAR)-ultrasonication-assisted method has been used to prepare BiOI-modified TiO2 nanotube arrays (BiOI/TNAs). The band gap of BiOI/TNAs for all the variations reveals absorption in the visible absorption. The surface morphology of BiOI/TNAs is shown in the nanoplate, nanoflake, and nanosheet forms with a vertical orientation perpendicular to TiO2. The crystalline structure of BiOI did not change the structure of the anatase TNAs, with the band gap energy of the BiOI/TNAs semiconductor in the visible region. The photocurrent density of the BiOI/TNAs extends to the visible-light range. BiOI/TNAs with 1 mM Bi and 1 mM KI on TNAs 40 V 1 h 50 V 30 min shows the optimum photocurrent density. A tandem dye-sensitized solar cell (DSSC)-photoelectrochemical (PEC) was used for hydrogen production in salty water. BiOI/TNAs optimum was used as the photoanode of the PEC cell. Solar to hydrogen conversion efficiency (STH) of tandem DSSC-PEC reaches 1.34% in salty water.