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1.
Proc Natl Acad Sci U S A ; 120(38): e2303466120, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37695920

RESUMEN

Low-grade wind with airspeed Vwind < 5 m/s, while distributed far more abundantly, is still challenging to extract because current turbine-based technologies require particular geography (e.g., wide-open land or off-shore regions) with year-round Vwind > 5 m/s to effectively rotate the blades. Here, we report that low-speed airflow can sensitively enable directional flow within nanowire-anchored ionic liquid (IL) drops. Specifically, wind-induced air/liquid friction continuously raises directional leeward fluid transport in the upper portion, whereas three-phase contact line (TCL) pinning blocks further movement of IL. To remove excessive accumulation of IL near TCL, fluid dives, and headwind flow forms in the lower portion, as confirmed by microscope observation. Such stratified circulating flow within single drop can generate voltage output up to ~0.84 V, which we further scale up to ~60 V using drop "wind farms". Our results demonstrate a technology to tap the widespread low-grade wind as a reliable energy resource.

2.
J Am Chem Soc ; 146(37): 25569-25577, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39094117

RESUMEN

Fluorinated ionic liquids (ILs) are well-known as electrolytes in the nitrogen (N2) electroreduction reaction due to their exceptional gas solubility. However, the influence of fluorinated functional group on N2 solvation and solubility enhancement remains unclear. Massive molecular dynamics simulations and free energy perturbation methods are conducted to investigate the N2 solubility in 11 traditional and 9 fluorinated ILs. It shows that the fluorinated IL of 1-Ethyl-3-methylimidazolium tris(pentafluoroethyl) trifluorophosphate ([Emim]FAP) exhibits ultrahigh solubility, 4.844 × 10-3, approximately 118 times higher than that of traditional IL 1-Ethyl-3-methylimidazolium nitrate ([Emim]NO3). Moreover, fluorinated ILs with more than 10 C-F bonds possess higher N2 solubility than others and show an exothermic nature during solvation. As the C-F bonds number in ILs decreases, the N2 solubility decreases significantly and displays the opposite endothermic behavior. To understand the ultrahigh N2 solubility in fluorinated ILs, we propose a concept of fluorine densification energy (FDE), referring to the average strength of interaction between atoms per unit volume in ILs with fluorine domains, demonstrating a linear relationship with C-F bonds. Physically, lower FDE results in lower N2-anion pair dissociation energy and higher free volume, finally enhancing the N2 solubility. Consequently, medium to long alkyl fluorine tails within a polar environment defines a distinct fluorine domain, emphasizing FDE's role in enhancing N2 solubility. Overall, these quantitative results will not only deepen the understanding of N2 solvation in ILs but may also shed light on the rational design of IL-based high-performance N2 capture and conversion technologies.

3.
J Am Chem Soc ; 146(19): 13588-13597, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38695646

RESUMEN

Membrane channel proteins (MCPs) play key roles in matter transport through cell membranes and act as major targets for vaccines and drugs. For emerging ionic liquid (IL) drugs, a rational understanding of how ILs affect the structure and transport function of MCP is crucial to their design. In this work, GPU-accelerated microsecond-long molecular dynamics simulations were employed to investigate the modulating mechanism of ILs on MCP. Interestingly, ILs prefer to insert into the lipid bilayer and channel of aquaporin-2 (AQP2) but adsorb on the entrance of voltage-gated sodium channels (Nav). Molecular trajectory and free energy analysis reflect that ILs have a minimal impact on the structure of MCPs but significantly influence MCP functions. It demonstrates that ILs can decrease the overall energy barrier for water through AQP2 by 1.88 kcal/mol, whereas that for Na+ through Nav is increased by 1.70 kcal/mol. Consequently, the permeation rates of water and Na+ can be enhanced and reduced by at least 1 order of magnitude, respectively. Furthermore, an abnormal IL gating mechanism was proposed by combining the hydrophobic nature of MCP and confined water/ion coordination effects. More importantly, we performed experiments to confirm the influence of ILs on AQP2 in human cells and found that treatment with ILs significantly accelerated the changes in cell volume in response to altered external osmotic pressure. Overall, these quantitative results will not only deepen the understanding of IL-cell interactions but may also shed light on the rational design of drugs and disease diagnosis.


Asunto(s)
Permeabilidad de la Membrana Celular , Activación del Canal Iónico , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Líquidos Iónicos/química , Líquidos Iónicos/metabolismo , Modelos Moleculares , Estructura Terciaria de Proteína , Agua/química , Línea Celular
4.
Lupus ; 33(5): 439-449, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38334360

RESUMEN

OBJECTIVE: This study aimed to investigate the possible role of granulin (GRN) in activating the TLR9-IFN-α pathway in renal tubular epithelial cells (RTECs) and explore clues that RTECs regulate the micro-environment of inflammatory response in lupus nephritis (LN). METHODS: Renal sections from 57 LN patients and 30 non-LN patients were sampled for histological study, and GRN overexpression RTECs were applied for cytological study. RESULTS: In the histological study, GRN is highly expressed in LN RTECs with tubulointerstitial inflammation (TII) and well co-localized with TLR9. ROC analysis suggested a potential relationship between GRN expression in RTECs and therapeutic response. Moreover, IFN-α also highly expressed in LN RTECs with TII, and the intensity of IFN-α is positively correlated with the co-localization intensity of GRN and TLR9. In the cytological study, LN serum, especially serum from LN with TII, activates the expression of TLR9 in RTECs, and GRN engages the interaction of TLR9 to activate the expression of IFN-α in RTECs. While TLR9 inhibitors can suppress the expression of IFN-α in RTECs, the degree of inhibition is dose-dependent. CONCLUSION: The expression of GRN in RTECs is associated with interstitial inflammation and therapeutic response. GRN may mediate the activation of the TLR9-IFN-α pathway in RTECs and involve in the micro-environment of inflammatory response in LN.


Asunto(s)
Granulinas , Lupus Eritematoso Sistémico , Nefritis Lúpica , Humanos , Granulinas/metabolismo , Inflamación/metabolismo , Interferón-alfa/metabolismo , Riñón/patología , Lupus Eritematoso Sistémico/patología , Nefritis Lúpica/patología , Receptor Toll-Like 9/metabolismo
5.
Mol Biol Rep ; 51(1): 816, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012539

RESUMEN

BACKGROUND: Pyropia yezoensis a commercially important red seaweed species, is susceptible to various microorganisms infections, among which bacterial infections are the most prominent ones. Pyropia yezoensis is often affected by harmful bacterial communities under high temperatures that can lead to its degradation and economic losses. The current study aimed to explore Pyropia yezoensis-associated microbiota and further identify potential isolates, which can degrade Pyropia yezoensis under high-temperature conditions. METHODS AND RESULTS: The 16S rRNA gene sequencing was used to identify the agarolytic bacterial species. The results showed that Chromohalobacter sp. strain AZ6, Pseudoalteromonas sp. strain AZ, Psychrobacter sp. strain AZ3, Vibrio sp. strain AZ, and Halomonas sp. strain AZ07 exhibited algicidal properties as these strains were more abundant at high temperature (25 °C). Among the five isolated strains, the potential isolate Halomonas sp. strain AZ07 showed high production of agarolytic enzymes, including lipase, protease, cellulase, and amylase. This study confirmed that the isolated strain could produce these four different enzymes. The strain Halomonas AZ07 was co-treated with Pyropia yezoensis cells under two different temperature environments, including 13 °C and 25 °C. The degradation of Pyropia yezoensis occurred at the optimum temperature of 25 °C and effectively degraded their cell wall, proteins, lipids, and carbohydrates. CONCLUSION: The successful cultivation of Pyropia yezoensis in coastal farm environments is dependent on specific temperature and environmental factors, and lower temperatures have been observed to be particularly beneficial for the survival and growth of Pyropia yezoensis. The temperature below 13 °C was confirmed to be the best niche for the symbiotic relationship of microbiota associated with Pyropia yezoensis for its growth, development, and production.


Asunto(s)
Halomonas , ARN Ribosómico 16S , Halomonas/genética , Halomonas/metabolismo , Halomonas/enzimología , ARN Ribosómico 16S/genética , Calor , Rhodophyta/genética , Filogenia , Microbiota/genética , Algas Marinas/metabolismo , Algas Marinas/microbiología , Temperatura , Algas Comestibles , Porphyra
6.
MAGMA ; 37(2): 185-198, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38386153

RESUMEN

OBJECTIVE: Conventional single-target field control for matrix gradient coils will add control complexity in MRI spatial encoding, such as designing specialized fields and sequences. This complexity can be reduced by multi-target field control, which is realized by optimizing the coil structure according to target fields. METHODS: Based on the principle of multi-target field control, the X, Y and Z gradient fields can be set as target fields, and all coil elements can then be divided into three groups to generate these fields. An improved simulated annealing algorithm is proposed to optimize the coil element distribution of each group to generate the corresponding target field. In the improved simulated annealing process, two swapping modes are presented, and randomly selected with certain probabilities that are set to 0.25, 0.5 and 0.75, respectively. The flexibility of the final designed structure is demonstrated by a spherical harmonic basis up to the full second order with single-target field control. An experimental platform is built to measure the gradient fields generated by the designed structure with multi-target target control. RESULTS: With three probabilities of swapping modes, three similar coil element distributions are optimized, and their maximum magnetic field errors for generating X, Y and Z gradients are all below 5%. The structure selected for the final design is the one with a probability of 0.75, considering the coil performance and structural symmetry. The maximum error for all target fields generated by single-target field control is also below 5%. The experimental results show that the measured gradient fields along the axes have enough strength and high linearity. CONCLUSIONS: With the proposed improved simulated annealing algorithm and swapping modes, multi-target field control for matrix gradient coils is verified and achieved in this study by optimizing the coil element distribution. Moreover, this study provides a solution to simplify the complexity of controlling the matrix gradient coil in spatial encoding.


Asunto(s)
Campos Magnéticos , Imagen por Resonancia Magnética , Diseño de Equipo , Imagen por Resonancia Magnética/métodos , Algoritmos
7.
MAGMA ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967865

RESUMEN

OBJECTIVE: To propose a deep learning-based low-field mobile MRI strategy for fast, high-quality, unshielded imaging using minimal hardware resources. METHODS: Firstly, we analyze the correlation of EMI signals between the sensing coil and the MRI coil to preliminarily verify the feasibility of active EMI shielding using a single sensing coil. Then, a powerful deep learning EMI elimination model is proposed, which can accurately predict the EMI components in the MRI coil signals using EMI signals from at least one sensing coil. Further, deep learning models with different task objectives (super-resolution and denoising) are strategically stacked for multi-level post-processing to enable fast and high-quality low-field MRI. Finally, extensive phantom and brain experiments were conducted on a home-built 0.2 T mobile brain scanner for the evaluation of the proposed strategy. RESULTS: 20 healthy volunteers were recruited to participate in the experiment. The results show that the proposed strategy enables the 0.2 T scanner to generate images with sufficient anatomical information and diagnostic value under unshielded conditions using a single sensing coil. In particular, the EMI elimination outperforms the state-of-the-art deep learning methods and numerical computation methods. In addition, 2 × super-resolution (DDSRNet) and denoising (SwinIR) techniques enable further improvements in imaging speed and quality. DISCUSSION: The proposed strategy enables low-field mobile MRI scanners to achieve fast, high-quality imaging under unshielded conditions using minimal hardware resources, which has great significance for the widespread deployment of low-field mobile MRI scanners.

8.
MAGMA ; 36(3): 409-418, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37081246

RESUMEN

OBJECTIVE: To design a lightweight permanent magnet for a lowfield movable head imaging MRI system. MATERIALS AND METHODS: To reduce the weight of the magnet, the pole pieces, anti-eddy current plates, and shimming rings were removed, and the distance between the two vertical yokes was shortened as much as possible. To compensate for the magnetic field deformation caused by the shortened distance between two vertical iron yokes, two side magnetic poles were added to the vertical yokes. The magnetic field distributions in magnetic poles, the iron yoke, and the spherical imaging region were simulated. Phantom and in vivo head imaging were conducted with a lowfield movable MRI prototype scanner equipped with the proposed permanent magnet. RESULTS: A permanent magnet with a center field of 0.19815 T, a homogeneity of 46 ppm over the 20 cm spherical imaging region, and a weight of 654 kg have been achieved. Acceptable images of a phantom and a human brain have been acquired with the prototype MRI scanner. DISCUSSION: The proposed permanent magnet design significantly reduces the magnet's weight compared with the conventional magnet structure and shows promise in promoting the development of lowfield compact MRI systems.


Asunto(s)
Imagen por Resonancia Magnética , Imanes , Humanos , Imagen por Resonancia Magnética/métodos , Campos Magnéticos , Magnetismo , Hierro
9.
Angew Chem Int Ed Engl ; 62(17): e202218472, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-36854948

RESUMEN

High-purity H2 production accompanied with a precise decarbonization opens an avenue to approach a carbon-neutral society. Metal-organic framework nanosheet membranes provide great opportunities for an accurate and fast H2 /CO2 separation, CO2 leakage through the membrane interlayer galleries decided the ultimate separation accuracy. Here we introduce low dose amino side groups into the Zn2 (benzimidazolate)4 conformation. Physisorbed CO2 served as interlayer linkers, gently regulated and stabilized the interlayer spacing. These evoked a synergistic effect of CO2 adsorption-assisted molecular sieving and steric hinderance, whilst exquisitely preserving apertures for high-speed H2 transport. The optimized amino membranes set a new record for ultrathin nanosheet membranes in H2 /CO2 separation (mixture separation factor: 1158, H2 permeance: 1417 gas permeation unit). This strategy provides an effective way to customize ultrathin nanosheet membranes with desirable molecular sieving ability.

10.
Angew Chem Int Ed Engl ; 62(42): e202310168, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37656770

RESUMEN

Conversion-type batteries apply the principle that more charge transfer is preferable. The underutilized electron transfer mode within two undermines the electrochemical performance of halogen batteries. Here, we realised a three-electron transfer lithium-halogen battery based on I- /I+ and Cl- /Cl0 couples by using a common commercial electrolyte saturated with Cl- anions. The resulting Li||tetrabutylammonium triiodide (TBAI3 ) cell exhibits three distinct discharging plateaus at 2.97, 3.40, and 3.85 V. Moreover, it has a high capacity of 631 mAh g-1 I (265 mAh g-1 electrode , based on entire mass loading) and record-high energy density of up to 2013 Wh kg-1 I (845 Wh kg-1 electrode ). To support these findings, experimental characterisations and density functional theory calculations were conducted to elucidate the redox chemistry involved in this novel interhalogen strategy. We believe our paradigm presented here has a foreseeable inspiring effect on other halogen batteries for high-energy-density pursuit.

11.
Anal Chem ; 94(2): 758-767, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34932315

RESUMEN

Limited by the rare efficient extraction system in extracting hydrophobic membrane protein complexes (MPCs) without compromising the stability of protein-protein interactions (PPIs), the in-depth functional study of MPCs has lagged far behind. In this study, the first systematic screening of ionic liquids (ILs) was performed and showed that triethylammonium acetate (TEAA) IL exhibited excellent performance in stabilizing PPIs, which was further confirmed by molecular docking simulations. By combining TEAA with the conventional detergent Nonidet P-40 (NP-40), a novel IL-based extraction system, i-TAN (TEAA IL with 1% NP-40), was proposed, which demonstrated superior performance in extracting and stabilizing MPCs, attributed to its larger size, more uniform distribution, and closer-to-neutral microenvironment of micelles. Extraction of MPCs with i-TAN allowed the confident identification of more hydrophobic EGFR-interacting proteins that are easily dissociated during the extraction process. Quantitative analysis of the difference in EGFR complexes between trastuzumab-sensitive and trastuzumab-resistant breast cancer cells provided comprehensive insights to understand the drug resistance mechanism, suggesting that i-TAN has great potential in interactomics and functional analysis of MPCs. This study provides a novel strategy for MPC extraction and downstream processing.


Asunto(s)
Líquidos Iónicos , Líquidos Iónicos/química , Proteínas de la Membrana , Simulación del Acoplamiento Molecular
12.
MAGMA ; 35(6): 967-980, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35689695

RESUMEN

OBJECTIVE: The goal of this work is to analyze the influence of the distributions and dimensions of the coil elements and to present a method for improving the performance of the matrix gradient coil. METHODS: Three typical models (five structures in total) are presented, and a double-layer biplanar matrix gradient coil is used to install coil elements. Two metrics, namely, the role of coil elements and mutual inductance between coil elements, are proposed to assess the performance of coil systems. An optimization approach to design matrix gradient coils is introduced based on analyzing the distributions and dimensions of coil elements. The flexibility of the magnetic field generation of the designed coil structure is demonstrated by generating full third-order spherical harmonic fields and different oblique gradient fields. RESULTS: Matrix gradient coils with suitable distributions are capable of generating target magnetic fields. The role of coil elements quantitatively illustrates that the coil elements have different impacts on generating magnetic fields. Increasing the coil element dimension within a certain range can reduce the mutual inductance between coil elements and improve the performance of the coil system. The designed novel double-layer biplanar matrix gradient coil achieves an acceptable performance in generating different magnetic fields. CONCLUSIONS: The proposed metrics can provide theoretical support for designing matrix gradient coils and evaluating their performance. The role of coil elements contributes to analyzing the distributions of coil elements to decrease the number of coil elements and power amplifiers. The mutual inductance between coil elements can be a reference for designing the dimensions of coil elements.

13.
MAGMA ; 35(6): 953-963, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35689696

RESUMEN

OBJECTIVE: The current distribution of the matrix gradient coil can be optimized via matrix gradient coil modeling to reduce the Lorentz force on individual coil elements. Two different modeling approaches are adopted, and their respective characteristics are summarized. METHODS: The magnetic field at each coil element is calculated. Then, the Lorentz force, torque, and deformation of the energized coil element in the magnetic field are derived. Two modeling approaches for matrix gradient coil, namely, optimizing coil element current (OCEC) modeling and optimizing coil element Lorentz force (OCEF) modeling, are proposed to reduce the Lorentz force on individual coil elements. The characteristics of different modeling approaches are compared by analyzing the influence of the weighting factor on the performance of the coil system. The current, Lorentz force, torque, and deformation results calculated via different modeling approaches are also compared. RESULTS: Coil element magnetic fields are much weaker than the main magnetic field, and their effect can be ignored. Matrix gradient coil modeling with different regularization terms can help to decrease the current and Lorentz force of coil elements. The performance of the coil system calculated via different modeling approaches is similar when suitable weighting factors are adopted. The two modeling approaches, OCEC and OCEF, can better reduce the maximum current and Lorentz force on individual coil elements compared with the traditional modeling approach. CONCLUSIONS: Different modeling approaches can help to optimize the current distribution of coil elements and satisfy various requirements while maintaining the performance of the coil system.

14.
Angew Chem Int Ed Engl ; 61(27): e202202515, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35504856

RESUMEN

Two-dimensional (2D) MXene-based lamellar membranes bearing interlayers of tunable hydrophilicity are promising for high-performance water purification. The current challenge lies in how to engineer the pore wall's surface properties in the subnano-confinement environment while ensuring its high selectivity. Herein, poly(ionic liquid)s, equipped with readily exchangeable counter anions, succeeded as a hydrophilicity modifier in addressing this issue. Lamellar membranes bearing nanochannels of tailorable hydrophilicity are constructed via assembly of poly(ionic liquid)-armored MXene nanosheets. By shifting the interlayer galleries from being hydrophilic to more hydrophobic via simple anion exchange, the MXene membrane performs drastically better for both the permeance (by two-fold improvement) and rejection (≈99 %). This facile method opens up a new avenue for building 2D material-based membranes of enhancing molecular transport and sieving effect.

15.
Angew Chem Int Ed Engl ; 61(9): e202113576, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-34931752

RESUMEN

A single-electron transfer mode coupled with the shuttle behavior of organic iodine batteries results in insufficient capacity, a low redox potential, and poor cycle durability. Sluggish kinetics are well known in conventional lithium-iodine (Li-I) batteries, inferior to other conversion congeners. Herein, we demonstrate new two-electron redox chemistry of I- /I+ with inter-halogen cooperation based on a developed haloid cathode. The new iodide-ion conversion battery exhibits a state-of-art capacity of 408 mAh gI-1 with fast redox kinetics and superior cycle stability. Equipped with a newly emerged 3.42 V discharge voltage plateau, a recorded high energy density of 1324 Wh kgI-1 is achieved. Such robust redox chemistry is temperature-insensitive and operates efficiently at -30 °C. With systematic theoretical calculations and experimental characterizations, the formation of Cl-I+ species and their functions are clarified.

16.
Chemphyschem ; 22(18): 1891-1899, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34236730

RESUMEN

Ionic liquids (ILs) are an important class of media that are usually used in combination with polar solvents to reduce costs and tune their physicochemical properties. In this regard, it is essential to understand the influence of adding solvents on the properties of ILs. In this work, the micro-heterogeneity and H-bonding interactions between a hydroxyl-functionalized IL, [HOEmim][TFSI], and acetonitrile (ACN) were investigated by attenuated total reflection Fourier transform infrared spectroscopy and molecular simulations. All studied IL-ACN mixtures were found to deviate from the ideal mixtures. The degree of deviations reaches the maximum at about x(ACN)=0.7 with the presence of both homogeneous clusters of pure IL/ACN and heterogeneous clusters of IL-ACN. With the addition of ACN to IL, the mixtures undergo the transformation from "ACN solvated in [HOEmim][TFSI]" to "[HOEmim][TFSI] solvated in ACN". It is found that the newly formed H-bonding interactions between the IL and ACN is the main factor that contributes to the red shifts of O-H, C2 -H, C4,5 -H, and Calkyl -H of [HOEmim]+ cation, and the blue shifts of C-D, C≡N of ACN, and C-F, S=O of [TFSI]- anion. These in-depth studies on the mixtures of hydroxyl-functionalized IL and acetonitrile would help to understand the micro-heterogeneity and H-bonding interactions of miscible solutions and shed light on exploring their applications.

17.
Chemphyschem ; 22(4): 419-429, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33502098

RESUMEN

Lithium-sulfur batteries with high energy density are considered as one of the most promising future energy storage devices. However, the parasitic lithium polysulfides shuttle phenomenon severely hinders the commercialization of such batteries. Ionic liquids have been found to suppress the lithium polysulfides solubility, diminishing the shuttle effect effectively. Herein, we performed classical molecular dynamics simulations to explore the microscopic mechanism and transport behaviors of typical Li2 S8 species in ionic liquids and ionic liquid-based electrolyte systems. We found that the trifluoromethanesulfonate anions ([OTf]- ) exhibit higher coordination strength with lithium ions compared with bis(trifluoromethanesulfonyl)imide anions ([TFSI]- ) in static microstructures. However, the dynamical characteristics indicate that the presence of the [OTf]- anions in ionic liquid electrolytes bring faster Li+ exchange rate and easier dissociation of Li+ solvation structures. Our simulation models offer a significant guidance to future studies on designing ionic liquid electrolytes for lithium-sulfur batteries.

18.
Phys Chem Chem Phys ; 23(5): 3246-3255, 2021 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-33236751

RESUMEN

Reducing carbon dioxide emissions is one of the possible solutions to prevent global climate change, which is urgently needed for the sustainable development of our society. In this work, easily available, biodegradable amino acid ionic liquids (AAILs) with great potential for CO2 absorption in the manned closed space such as spacecraft, submarines and other manned devices are used as the basic material. Molecular dynamics simulations and ab initio calculations were performed for 12 AAILs ([P4444][X] and [P66614][X], [X] = X = [GLy]-, [Im]-, [Pro]-, [Suc]-, [Lys]-, [Asp]2-), and the dynamic characteristics and the internal mechanism of AAILs to improve CO2 absorption capacity were clarified. Based on structural analysis and the analysis of interaction energy including van der Waals and electrostatic interaction energy, it was revealed that the anion of ionic liquids dominates the interaction between CO2 and AAILs. At the same time, the CO2 absorption capacity of AAILs increases in the order [Asp]2- < [Suc]- < [Lys]- < [Pro]- < [Im]- < [Gly]-. Meanwhile, the synergistic absorption of CO2 by multiple-sites of amino and carboxyl groups in the anion was proved by DFT calculations. These findings show that the anion of AAILs can be an effective factor to regulate the CO2 absorption process, which can also provide guidance for the rational and targeted molecular design of AAILs for CO2 capture, especially in the manned closed space.


Asunto(s)
Aminoácidos/química , Dióxido de Carbono/química , Líquidos Iónicos/química , Teoría Funcional de la Densidad , Modelos Químicos , Simulación de Dinámica Molecular
19.
Angew Chem Int Ed Engl ; 60(19): 10910-10918, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33634560

RESUMEN

Electrocatalytic C-N bond coupling to convert CO2 and N2 molecules into urea under ambient conditions is a promising alternative to harsh industrial processes. However, the adsorption and activation of inert gas molecules and then the driving of the C-N coupling reaction is energetically challenging. Herein, novel Mott-Schottky Bi-BiVO4 heterostructures are described that realize a remarkable urea yield rate of 5.91 mmol h-1 g-1 and a Faradaic efficiency of 12.55 % at -0.4 V vs. RHE. Comprehensive analysis confirms the emerging space-charge region in the heterostructure interface not only facilitates the targeted adsorption and activation of CO2 and N2 molecules on the generated local nucleophilic and electrophilic regions, but also effectively suppresses CO poisoning and the formation of endothermic *NNH intermediates. This guarantees the desired exothermic coupling of *N=N* intermediates and generated CO to form the urea precursor, *NCON*.

20.
Langmuir ; 36(31): 9323-9332, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32673488

RESUMEN

Enhancing molecular interaction is critical for improving the immobilization and stability of proteins on TiO2 surfaces. In this work, mesoporous TiO2 materials with varied pore geometries were decorated with phenyl phosphoric acid (PPA), followed by a thermal treatment to obtain chemically heterogeneous C-TiO2 samples without changing the geometry and crystalline structure, which can keep the advantages of both carbon and TiO2. The molecular interaction force between the protein and the surfaces was measured using atomic force microscopy by decomposing from the total adhesion forces, showing that the surface chemistry determines the interaction strength and depends on the amount of partial carbon coverage on the TiO2 surface (∼40-80%). Samples with 58.3% carbon coverage provide the strongest molecular interaction force, consistent with the observation from the detected friction force. Surface-enhanced Raman scattering and electrochemical biosensor measurements for these C-TiO2 materials were further conducted to illustrate their practical implications, implying their promising applications such as in protein detection and biosensing.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , Microscopía de Fuerza Atómica , Titanio
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