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In this work, biocompatible composite fibers were prepared from human hair keratin and plant cellulose with different proportions by the wet-spinning method, and their properties and performance, including chemical structures, morphology, mechanical strength, and cell proliferation and attachment, were systematically investigated. It showed that the best proportion of the keratin/cellulose mass ratio was 30:70, and its tensile strength reached 277 MPa (elongation at break can be 27%), which is higher than that of the regenerated cellulose fiber (193 MPa, 12%). Its viability and proliferation of L929 murine fibroblast cells are also better than those of the regenerated cellulose fiber. Atomistic simulations were carried out and demonstrated the formation of hydrogen bonds between keratin and cellulose molecules, clarifying that the ratio of keratin has a significant effect on the aggregation structures in the solution and that the hydrogen bonds formed between keratin and cellulose molecules have a distinct contribution to the biocompatible composites. This work demonstrates the potential of the prepared composite fiber in biomedical applications and provides an innovative way to utilize waste human hair as a high-value raw material., Validerad;2024;Nivå 2;2024-01-17 (joosat);Funder: National Natural Science Foundation of China (grant no.22178342); Zhengzhou High-Level Talent (20180300045); Scientific and Technological Project of Henan Province (212102210035);Full text license: CC BY

In this work, biocompatible composite fibers were prepared from human hair keratin and plant cellulose with different proportions by the wet-spinning method, and their properties and performance, including chemical structures, morphology, mechanical strength, and cell proliferation and attachment, were systematically investigated. It showed that the best proportion of the keratin/cellulose mass ratio was 30:70, and its tensile strength reached 277 MPa (elongation at break can be 27%), which is higher than that of the regenerated cellulose fiber (193 MPa, 12%). Its viability and proliferation of L929 murine fibroblast cells are also better than those of the regenerated cellulose fiber. Atomistic simulations were carried out and demonstrated the formation of hydrogen bonds between keratin and cellulose molecules, clarifying that the ratio of keratin has a significant effect on the aggregation structures in the solution and that the hydrogen bonds formed between keratin and cellulose molecules have a distinct contribution to the biocompatible composites. This work demonstrates the potential of the prepared composite fiber in biomedical applications and provides an innovative way to utilize waste human hair as a high-value raw material., Validerad;2024;Nivå 2;2024-01-17 (joosat);Funder: National Natural Science Foundation of China (grant no.22178342); Zhengzhou High-Level Talent (20180300045); Scientific and Technological Project of Henan Province (212102210035);Full text license: CC BY

The properties and applications of ionic liquids (ILs) have been widely investigated when they are confined within nanochannels such as carbon nanotubes (CNTs). The confined ILs exhibit very different properties from their bulk state due to a nanoconfinement effect, which plays an important role in the performances of devices with ILs. In this work, we studied the effect of the charge carried by CNTs on confined ILs inside CNTs using molecular dynamics simulations. In charged CNTs, cations and anions are distributed separately along the radial directions, and the transition of orientations of the cations between parallel and vertical to CNTs occurs by changing the charge state of CNTs. The number of hydrogen bonds (HBs) formed by the confined ILs can be reduced by switching the surface charge of CNTs from positive to negative due to the contact modes between cations and anions as well as the distributions of cations in CNTs. The diffusivities along and vertical to the axial direction of CNTs were found to be non-monotonic owing to the "trade-off" effect from both ion pair interlocking and anchoring ILs on the CNT walls. Additionally, the region-dependent dynamics of ILs were also related to the intermolecular interactions in different regions of CNTs. Furthermore, the vibrational modes of ILs were obviously influenced in highly charged CNTs as determined by calculating the density of vibrational states, which demonstrated the transitions in the structure and interactions. The density distributions changed from single layer to double layers when increasing the pore size of neutral CNTs while the hydrogen bonds exhibited a non-monotonic tendency versus the pore sizes. Our results might help to understand the structure and dynamics of confined ILs as well as aid optimizing the performance of devices with ILs. Exploration of the impact of charge states of carbon nanotubes on region-dependent properties of confined ionic liquids and the relation between ionic dynamics an, Funding Agencies|Basic and Applied Basic Research Foundation of Guangdong Province [2022A1515010873, 2023A1515012535]; Guangdong Basic and Applied Basic Research Foundation [22003080]; National Natural Science Foundation of China

Poly(ionic liquid)s (PIL) are common precursors for heteroatom-doped carbon materials. Despite a relatively higher carbonization yield, the PIL-to-carbon conversion process faces challenges in preserving morphological and structural motifs on the nanoscale. Assisted by a thin polydopamine coating route and ion exchange, imidazolium-based PIL nanovesicles were successfully applied in morphology-maintaining carbonization to prepare carbon composite nanocapsules. Extending this strategy further to their composites, we demonstrate the synthesis of carbon composite nanocapsules functionalized with iron nitride nanoparticles of an ultrafine, uniform size of 3–5 nm (termed “FexN@C”). Due to its unique nanostructure, the sulfur-loaded FexN@C electrode was tested to efficiently mitigate the notorious shuttle effect of lithium polysulfides (LiPSs) in Li–S batteries. The cavity of the carbon nanocapsules was spotted to better the loading content of sulfur. The well-dispersed iron nitride nanoparticles effectively catalyze the conversion of LiPSs to Li2S, owing to their high electronic conductivity and strong binding power to LiPSs. Benefiting from this well-crafted composite nanostructure, the constructed FexN@C/S cathode demonstrated a fairly high discharge capacity of 1085 mAh g–1 at 0.5 C initially, and a remaining value of 930 mAh g–1 after 200 cycles. In addition, it exhibits an excellent rate capability with a high initial discharge capacity of 889.8 mAh g–1 at 2 C. This facile PIL-to-nanocarbon synthetic approach is applicable for the exquisite design of complex hybrid carbon nanostructures with potential use in electrochemical energy storage and conversion.

Liquid solutions and mixtures are part of our everyday lives and also important for their chemical and industrial applications. While considered fairly unattractive substances when kept in bottles and containers, their behavior as molecules can be completely the opposite, continuously attracting scientists to explain it better. Very strong repulsive and attractive interactions between the molecules can create most intriguing local structures, aggregates and complexes, whose spatial organization is often difficult to rationalize. Also, the same mixture can behave completely differently depending on the composition ratio, affecting strongly its macroscopic properties. To gain insight into the complex world of binary liquid mixtures, deep eutectic solvents and ionic liquid systems, combined theoretical and experimental studies are necessary. In this chapter we introduce the methodology of computer simulations and illustrate with several examples of the often-unexpected behavior of many liquid mixtures.

Proton/Fluoride spin-lattice ($T_1$) nuclear magnetic relaxation dispersion (NMRD) measurements of 1-butyl-3-methyl-$1H$-imidazolium hexa-fluorophosphate, [$C_4mim][PF_6]$, have been carried out using high field spectrometers and fast-field-cycling instrument at proton Larmor frequencies ranging from 10kHz to 40 MHz, at different temperatures. The NMRD profiles are interpreted by means of a simple relaxation model based on the inter- and intra-ionic dipole-dipole relaxation mechanism. Using an atomic molecular-ion dynamic simulation at 323 K the relevant spin dipole-dipole(DD) correlation functions are calculated. The results indicate the NMRD profiles can be rationalized using intra- and inter-ionic spin DD interactions, however, both are mainly modulated by ionic reorientation because of temporary correlations with cations, where modulation by translational diffusion plays a minor role. Reorientational dynamics of charge-neutral ion couples (i.e. $[C_4mim]^{...}[PF_6]$) and $[C_4mim]^{+}$ ions are in the nano-second (ns) time range whereas the reorientation of $[PF_6]{^-}$ is characterized by a reorientational correlation time in the pico-second (ps) regime. Based on the NMRD profiles we conclude the main relaxation mechanism for $[PF_6]{^-}$ is, due to fast internal reorientational motion, a partially averaged F-F intra and a F-H inter-ionic DD coupling as the anion resides in close proximity to its temporary oppositely charged cation partner. The F-$T_1$- NMRD data display a ns dispersions which is interpreted as being due to correlated reorientational modulations resultant from H-containing charge-neutral ion couple $[C_4mim]^{...}[PF_6]$. The analysis of ionicity is based on the free anion fraction, $f$ and it increase with temperature with $f$ $\rightarrow$ 1 at the highest temperatures investigated. The fraction is obtained from the H-F NMRD profiles as correlated-non-correlated dynamics of the ions. The analysis of $T_1$ relaxation rates of C, H, F and P at

Proton/Fluoride spin-lattice ($T_1$) nuclear magnetic relaxation dispersion (NMRD) measurements of 1-butyl-3-methyl-$1H$-imidazolium hexa-fluorophosphate, [$C_4mim][PF_6]$, have been carried out using high field spectrometers and fast-field-cycling instrument at proton Larmor frequencies ranging from 10kHz to 40 MHz, at different temperatures. The NMRD profiles are interpreted by means of a simple relaxation model based on the inter- and intra-ionic dipole-dipole relaxation mechanism. Using an atomic molecular-ion dynamic simulation at 323 K the relevant spin dipole-dipole(DD) correlation functions are calculated. The results indicate the NMRD profiles can be rationalized using intra- and inter-ionic spin DD interactions, however, both are mainly modulated by ionic reorientation because of temporary correlations with cations, where modulation by translational diffusion plays a minor role. Reorientational dynamics of charge-neutral ion couples (i.e. $[C_4mim]^{...}[PF_6]$) and $[C_4mim]^{+}$ ions are in the nano-second (ns) time range whereas the reorientation of $[PF_6]{^-}$ is characterized by a reorientational correlation time in the pico-second (ps) regime. Based on the NMRD profiles we conclude the main relaxation mechanism for $[PF_6]{^-}$ is, due to fast internal reorientational motion, a partially averaged F-F intra and a F-H inter-ionic DD coupling as the anion resides in close proximity to its temporary oppositely charged cation partner. The F-$T_1$- NMRD data display a ns dispersions which is interpreted as being due to correlated reorientational modulations resultant from H-containing charge-neutral ion couple $[C_4mim]^{...}[PF_6]$. The analysis of ionicity is based on the free anion fraction, $f$ and it increase with temperature with $f$ $\rightarrow$ 1 at the highest temperatures investigated. The fraction is obtained from the H-F NMRD profiles as correlated-non-correlated dynamics of the ions. The analysis of $T_1$ relaxation rates of C, H, F and P at

Proton/Fluoride spin-lattice ($T_1$) nuclear magnetic relaxation dispersion (NMRD) measurements of 1-butyl-3-methyl-$1H$-imidazolium hexa-fluorophosphate, [$C_4mim][PF_6]$, have been carried out using high field spectrometers and fast-field-cycling instrument at proton Larmor frequencies ranging from 10kHz to 40 MHz, at different temperatures. The NMRD profiles are interpreted by means of a simple relaxation model based on the inter- and intra-ionic dipole-dipole relaxation mechanism. Using an atomic molecular-ion dynamic simulation at 323 K the relevant spin dipole-dipole(DD) correlation functions are calculated. The results indicate the NMRD profiles can be rationalized using intra- and inter-ionic spin DD interactions, however, both are mainly modulated by ionic reorientation because of temporary correlations with cations, where modulation by translational diffusion plays a minor role. Reorientational dynamics of charge-neutral ion couples (i.e. $[C_4mim]^{...}[PF_6]$) and $[C_4mim]^{+}$ ions are in the nano-second (ns) time range whereas the reorientation of $[PF_6]{^-}$ is characterized by a reorientational correlation time in the pico-second (ps) regime. Based on the NMRD profiles we conclude the main relaxation mechanism for $[PF_6]{^-}$ is, due to fast internal reorientational motion, a partially averaged F-F intra and a F-H inter-ionic DD coupling as the anion resides in close proximity to its temporary oppositely charged cation partner. The F-$T_1$- NMRD data display a ns dispersions which is interpreted as being due to correlated reorientational modulations resultant from H-containing charge-neutral ion couple $[C_4mim]^{...}[PF_6]$. The analysis of ionicity is based on the free anion fraction, $f$ and it increase with temperature with $f$ $\rightarrow$ 1 at the highest temperatures investigated. The fraction is obtained from the H-F NMRD profiles as correlated-non-correlated dynamics of the ions. The analysis of $T_1$ relaxation rates of C, H, F and P at

Proton/fluoride spin-lattice (T1) nuclear magnetic relaxation dispersion (NMRD) measurements of 1-butyl-3-methyl-1H-imidazolium hexafluorophosphate, [C4mim][PF6], have been carried out using high field spectrometers and a fast-field-cycling instrument at proton Larmor frequencies ranging from 10 kHz to 40 MHz, at different temperatures. The NMRD profiles are interpreted by means of a simple relaxation model based on the inter- and intra-ionic dipole-dipole relaxation mechanism. Using an atomic molecular-ion dynamic simulation at 323 K the relevant spin dipole-dipole (DD) correlation functions are calculated. The results indicate that the NMRD profiles can be rationalized using intra- and inter-ionic spin DD interactions, however, anions are mainly modulated by ionic reorientation because of temporary correlations with cations, where modulation by translational diffusion plays a minor role. Reorientational dynamics of charge-neutral ion couples (i.e. [C4mim]⋯[PF6]) and [C4mim]+ ions are in the nano-second (ns) time range whereas the reorientation of [PF6]- is characterized by a reorientational correlation time in the pico-second (ps) regime. Based on the NMRD profiles we conclude that the main relaxation mechanism for [PF6]- is due to fast internal reorientational motion, a partially averaged F-F intra- and F-H inter-ionic DD coupling as the anion resides in close proximity to its temporary oppositely charged cation partner. The F-T1-NMRD data display a ns dispersion which is interpreted as being due to correlated reorientational modulations resulting from the H-containing charge-neutral ion couple [C4mim]⋯[PF6]. The analysis of ionicity is based on the free anion fraction, f, and it increases with temperature with f → 1 at the highest temperatures investigated. The fraction is obtained from the H-F NMRD profiles as correlated-non-correlated dynamics of the ions. The analysis of T1 relaxation rates of C, H, F and P at high fields cannot generally give the fraction of, QC 20171025

Proton/Fluoride spin-lattice ($T_1$) nuclear magnetic relaxation dispersion (NMRD) measurements of 1-butyl-3-methyl-$1H$-imidazolium hexa-fluorophosphate, [$C_4mim][PF_6]$, have been carried out using high field spectrometers and fast-field-cycling instrument at proton Larmor frequencies ranging from 10kHz to 40 MHz, at different temperatures. The NMRD profiles are interpreted by means of a simple relaxation model based on the inter- and intra-ionic dipole-dipole relaxation mechanism. Using an atomic molecular-ion dynamic simulation at 323 K the relevant spin dipole-dipole(DD) correlation functions are calculated. The results indicate the NMRD profiles can be rationalized using intra- and inter-ionic spin DD interactions, however, both are mainly modulated by ionic reorientation because of temporary correlations with cations, where modulation by translational diffusion plays a minor role. Reorientational dynamics of charge-neutral ion couples (i.e. $[C_4mim]^{...}[PF_6]$) and $[C_4mim]^{+}$ ions are in the nano-second (ns) time range whereas the reorientation of $[PF_6]{^-}$ is characterized by a reorientational correlation time in the pico-second (ps) regime. Based on the NMRD profiles we conclude the main relaxation mechanism for $[PF_6]{^-}$ is, due to fast internal reorientational motion, a partially averaged F-F intra and a F-H inter-ionic DD coupling as the anion resides in close proximity to its temporary oppositely charged cation partner. The F-$T_1$- NMRD data display a ns dispersions which is interpreted as being due to correlated reorientational modulations resultant from H-containing charge-neutral ion couple $[C_4mim]^{...}[PF_6]$. The analysis of ionicity is based on the free anion fraction, $f$ and it increase with temperature with $f$ $\rightarrow$ 1 at the highest temperatures investigated. The fraction is obtained from the H-F NMRD profiles as correlated-non-correlated dynamics of the ions. The analysis of $T_1$ relaxation rates of C, H, F and P at

Proton/Fluoride spin-lattice ($T_1$) nuclear magnetic relaxation dispersion (NMRD) measurements of 1-butyl-3-methyl-$1H$-imidazolium hexa-fluorophosphate, [$C_4mim][PF_6]$, have been carried out using high field spectrometers and fast-field-cycling instrument at proton Larmor frequencies ranging from 10kHz to 40 MHz, at different temperatures. The NMRD profiles are interpreted by means of a simple relaxation model based on the inter- and intra-ionic dipole-dipole relaxation mechanism. Using an atomic molecular-ion dynamic simulation at 323 K the relevant spin dipole-dipole(DD) correlation functions are calculated. The results indicate the NMRD profiles can be rationalized using intra- and inter-ionic spin DD interactions, however, both are mainly modulated by ionic reorientation because of temporary correlations with cations, where modulation by translational diffusion plays a minor role. Reorientational dynamics of charge-neutral ion couples (i.e. $[C_4mim]^{...}[PF_6]$) and $[C_4mim]^{+}$ ions are in the nano-second (ns) time range whereas the reorientation of $[PF_6]{^-}$ is characterized by a reorientational correlation time in the pico-second (ps) regime. Based on the NMRD profiles we conclude the main relaxation mechanism for $[PF_6]{^-}$ is, due to fast internal reorientational motion, a partially averaged F-F intra and a F-H inter-ionic DD coupling as the anion resides in close proximity to its temporary oppositely charged cation partner. The F-$T_1$- NMRD data display a ns dispersions which is interpreted as being due to correlated reorientational modulations resultant from H-containing charge-neutral ion couple $[C_4mim]^{...}[PF_6]$. The analysis of ionicity is based on the free anion fraction, $f$ and it increase with temperature with $f$ $\rightarrow$ 1 at the highest temperatures investigated. The fraction is obtained from the H-F NMRD profiles as correlated-non-correlated dynamics of the ions. The analysis of $T_1$ relaxation rates of C, H, F and P at

In the last few decades, ionic liquids (ILs) have gained significant attention as lubricants and lubricant additives due to their polar nature, low vapour pressure and tunable physicochemical properties. In this work, quantum chemistry calculations and atomistic Molecular Dynamics (MD) simulations were employed to predict thermal degradation mechanisms of a potential lubricating agent - the tributyloctylphosphonium bis(oxalato) borate ([P-4,P-4,P-4,P-8][BOB]) IL. It was found that the onset of decomposition of the studied IL coincides with a cleavage of the B-O bonds in the [BOB](-) anion. Consequently, a series of chemical reactions of the [P-4,P-4,P-4,P-8](+) cation with the [BOB](-) anion was triggered yielding alkylboranes, alkenes, trialkylphosphines, CO and CO2. Another ionic system, consisting of [P-4,P-4,P-4,P-8][Cl], was also tested for a comparison. Thermogravimetric measurements have shown a higher thermal stability of [P-4,P-4,P-4,P-8][BOB] compared to that of [P-4,P-4,P-4,P-8][Cl] at least at the initial stage of decomposition, in accord with the presented calculations. Quantum chemical frequency calculations also agreed with the experimental Fourier Transform Infrared (FTIR) spectroscopy results., QC 20161005

Shizishan is the largest Cu(Au) orefield in the Tongling district, which is dominated by skarn and stratabound skarn deposits. Hydrothermal mineralisation can be divided into three stages, skarn, quartz-sulphide and carbonate-quartz-sulphide. The deposits are rich in fluid inclusions which occur in garnet, quartz and calcite and can be divided into three types, gas-rich, liquid-rich and daughter mineral-bearing polyphase brine inclusions. The daughter minerals are mainly halites, with minor sylvite and other minerals, suggesting that the ore-forming fluids belong to the NaCl-H2O system and are of an unsaturated NaCl-type. The ore-forming fluids were derived from the magma and existed in a supercritical condition in the early stages. They evolved from high temperature and high salinity to moderate temperature and low-moderate salinity, corresponding well with the mineralisation stages. Addition of meteoric water occurred during fluid evolution. A temperature decrease, decompression and boiling of the fluids were the main factors for the enrichment of large amounts of Cu and Au., Shizishan is the largest Cu(Au) orefield in the Tongling district, which is dominated by skarn and stratabound skarn deposits. Hydrothermal mineralisation can be divided into three stages, skarn, quartz-sulphide and carbonate-quartz-sulphide. The deposits are rich in fluid inclusions which occur in garnet, quartz and calcite and can be divided into three types, gas-rich, liquid-rich and daughter mineral-bearing polyphase brine inclusions. The daughter minerals are mainly halites, with minor sylvite and other minerals, suggesting that the ore-forming fluids belong to the NaCl-H2O system and are of an unsaturated NaCl-type. The ore-forming fluids were derived from the magma and existed in a supercritical condition in the early stages. They evolved from high temperature and high salinity to moderate temperature and low-moderate salinity, corresponding well with the mineralisation stages. Addition of meteoric water occurred during fluid evolution. A temperature decrease, decompression and boiling of the fluids were the main factors for the enrichment of large amounts of Cu and Au.