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1.
Chemistry ; 30(13): e202303424, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38116816

RESUMEN

High-efficacy recycling of spent lithium cobalt oxide (LiCoO2 ) batteries is one of the key tasks in realizing a global resource security strategy due to the rareness of lithium (Li) and cobalt (Co) resources. However, it is of great significance to develop the innovative recycle methods for spent LiCoO2 , simultaneously realizing the efficient recovery of valuable elements and the regeneration of high-performance LiCoO2 . Herein, a novel strategy of regenerating LiCoO2 cathode is proposed, which involves the preparation of micro-spherical aluminum (Al)-doped lithium-lacked precursor (Li2x Co1-x-y Al2/3y CO3, remarked as "PLCAC") via ammonium bicarbonate coprecipitation. The comprehensive conditions affecting particle growth kinetics, morphology and particle size the has been investigated in detail by physical characterizations and electrochemical measurements. And the optimized Al-doped LiCoO2 materials with high-density sphericity (LiCo1-z Alz O2 , remarked as "LCAO") shows a high initial specific capacity of 161 mAh g-1 at 0.1 C and excellent capacity retention of 99.5 % within 100 cycles at 1 C in the voltage range of 2.8 to 4.3 V. Our work provides valuable insights into the featured design of LiCoO2 precursors and cathode materials from spent LiCoO2 batteries, potentially guaranteeing the high-efficacy recycling and utilization of strategic resources.

2.
Chem Biodivers ; 21(2): e202301366, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38073179

RESUMEN

The interaction mechanism between trypsin and fulvic acid was analyzed by multispectral method and molecular docking simulation. The fluorescence spectra showed that fulvic acid induced static quenching of trypsin. The validity of this conclusion was further substantiated through the computation of the binding constants. The thermodynamic parameters show that the reaction is mainly controlled by van der Waals force and hydrogen bond force, and the reaction is spontaneous. In addition, based on the obtained binding distance, there may be a non-radiative energy transfer between the two. The ultraviolet spectrum showed that fulvic acid could shift the absorption peak of trypsin, indicating that fulvic acid had an effect on the secondary structure of trypsin. According to the synchronous fluorescence spectrum results, fulvic acid primarily interacts with tryptophan residues in trypsin and induces alterations in their microenvironment. Three-dimensional fluorescence spectrum and circular dichroism further proves this conclusion. The molecular docking simulation reveals that the interaction between the two groups primarily arises from hydrogen bonding and van der Waals forces. The findings suggest that FA has the ability to induce conformational changes in trypsin's secondary structure.


Asunto(s)
Benzopiranos , Simulación del Acoplamiento Molecular , Tripsina/química , Tripsina/metabolismo , Unión Proteica , Dicroismo Circular , Termodinámica , Espectrometría de Fluorescencia , Sitios de Unión , Enlace de Hidrógeno
3.
Chem Biodivers ; 21(2): e202301554, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38128109

RESUMEN

The interaction between chloramphenicol (CHL) and pepsin (PEP), as well as the impact of CHL on PEP conformation, were investigated using spectroscopic techniques and molecular docking simulations in this study. The experimental results demonstrate that CHL exhibits a static quenching effect on PEP. The thermodynamic parameters indicate that the reaction between CHL and PEP is spontaneous, primarily driven by hydrogen bonding and van der Waals forces. Moreover, the binding distance of r<7 nm suggests the occurrence of Förster's non-radiative energy transfer between these two molecules. In the synchronous fluorescence spectrum, the maximum fluorescence intensity of PEP produced a redshift phenomenon, indicating that CHL was bound to tryptophan residues of PEP. The addition of CHL induces changes in the secondary structure of PEP, as confirmed by the observed alterations in peak values in three-dimensional fluorescence spectra. The UV spectra reveal a redshift of 3 nm in the maximum absorption peak, indicating a conformational change in the secondary structure of PEP upon addition of CHL. Circular dichroism analysis demonstrates significant alterations in the α-helix, ß-sheet, ß-turn, and random coil contents of PEP before and after CHL incorporation, further confirming its ability to modulate the secondary structure of PEP.


Asunto(s)
Antibacterianos , Cloranfenicol , Antibacterianos/farmacología , Cloranfenicol/farmacología , Espectrometría de Fluorescencia , Pepsina A/química , Pepsina A/metabolismo , Simulación del Acoplamiento Molecular , Termodinámica , Dicroismo Circular , Sitios de Unión , Unión Proteica
4.
Small ; : e2308564, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38049201

RESUMEN

Lithium-sulfur batteries (LSBs) with ultra-high energy density (2600 W h kg-1 ) and readily available raw materials are emerging as a potential alternative device with low cost for lithium-ion batteries. However, the insulation of sulfur and the unavoidable shuttle effect leads to slow reaction kinetics of LSBs, which in turn cause various roadblocks including poor rate capability, inferior cycling stability, and low coulombic efficiency. The most effective way to solve the issues mentioned above is to rationally design and control the synthesis of the cathode host for LSBs. Transition metal phosphides (TMPs) with good electrical conductivity and dual adsorption-conversion capabilities for polysulfide (PS) are regarded as promising cathode hosts for new-generation LSBs. In this review, the main obstacles to commercializing the LSBs and the development processes of their cathode host are first elaborated. Then, the sulfur fixation principles, and synthesis methods of the TMPs are briefly summarized and the recent progress of TMPs in LSBs is reviewed in detail. Finally, a perspective on the future research directions of LSBs is provided.

5.
Small ; 19(52): e2304162, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37642534

RESUMEN

Ether-based electrolytes exhibit excellent performance when applied in different anode materials of sodium ion batteries (SIBs), but their exploration on cathode material is deficient and the degradation mechanism is still undiscovered. Herein, various battery systems with different operation voltage ranges are designed to explore the electrochemical performance of ether electrolyte. It is found for the first time that the deterioration mechanism of ether electrolyte is closely related to the "redox shuttle" between cathode and low-potential anode. The "shuttle" is discovered to occur when the potential of anodes is below 0.57 V, and the gas products coming from "shuttle" intermediates are revealed by differential electrochemical mass spectrometry (DEMS). Moreover, effective inhibition strategies by protecting low-potential anodes are proposed and verified; ethylene carbonate (EC) is found to be very effective as an additive by forming an inorganics-rich solid electrolyte interphase (SEI) on low-potential anodes, thereby suppressing the deterioration of ether electrolytes. This work reveals the failure mechanism of ether-based electrolytes applied in SIBs and proposes effective strategies to suppress the "shuttle," which provides a valuable guidance for advancing the application of ether-based electrolytes in SIBs.

6.
Molecules ; 28(6)2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36985629

RESUMEN

In the current study, the interaction of minocycline hydrochloride (MC) and trypsin (TRP) was studied using fluorescence spectroscopy, synchronous fluorescence spectroscopy, three-dimensional fluorescence spectroscopy, UV-Vis spectroscopy, and molecular docking simulation techniques. The results show that the fluorescence quenching of trypsin at different degrees can be caused by minocycline hydrochloride at different temperatures. According to the Stern-Volmer equation, the fluorescence quenching type was static quenching. By calculating critical distance, we concluded that there is a possibility of non-radiative energy transfer between minocycline hydrochloride and trypsin. The effect of minocycline hydrochloride on the secondary structure of trypsin was demonstrated using ultraviolet spectroscopy. Synchronous fluorescence spectroscopy showed that minocycline hydrochloride could bind to tryptophan residues in trypsin, resulting in corresponding changes in the secondary structure of trypsin. Three-dimensional fluorescence spectroscopy showed that minocycline hydrochloride had a particular effect on the microenvironment of trypsin that led to changes in the secondary structure of trypsin. The molecular docking technique demonstrated that the binding of minocycline hydrochloride and trypsin was stable. Circular dichroism showed that the secondary structure of trypsin could be changed by minocycline hydrochloride.


Asunto(s)
Minociclina , Simulación del Acoplamiento Molecular , Tripsina/química , Unión Proteica , Espectrofotometría Ultravioleta , Termodinámica , Dicroismo Circular , Espectrometría de Fluorescencia , Sitios de Unión
7.
Molecules ; 28(13)2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37446692

RESUMEN

Heavy metal pollution caused by industrial wastewater such as mining and metallurgical wastewater is a major global concern. Therefore, this study used modified lignite as a low-cost adsorbent for heavy metal ions. Pingzhuang lignite was dissolved and modified using Fusarium lignite B3 to prepare a biotransformed-lignite adsorbent (BLA). The O, H, and N contents of the BLA increased after transformation, and the specific surface area increased from 1.81 to 5.66 m2·g-1. Various adsorption properties were investigated using an aqueous solution of Cu(Ⅱ). The kinetic and isothermal data were well-fitted by pseudo-second-order and Langmuir models, respectively. The Langmuir model showed that the theoretical Cu(II) adsorption capacity was 71.47 mg·g-1. Moreover, large particles and a neutral pH were favorable for the adsorption of heavy metal ions. The adsorption capacities of raw lignite and BLA were compared for various ions. Microbial transformation greatly improved the adsorption capacity, and the BLA had good adsorption and passivation effects with Cu(II), Mn(II), Cd(II), and Hg(II). Investigation of the structural properties showed that the porosity and specific surface area increased after biotransformation, and there were more active groups such as -COOH, Ar-OH, and R-OH, which were involved in the adsorption performance.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes Químicos del Agua , Carbón Mineral , Aguas Residuales , Metales Pesados/análisis , Agua , Iones , Adsorción , Cinética , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno
8.
Entropy (Basel) ; 25(3)2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36981303

RESUMEN

Deep learning has led to significant progress in the fault diagnosis of mechanical systems. These intelligent models often require large amounts of training data to ensure their generalization capabilities. However, the difficulty of obtaining turbine rotor fault data poses a new challenge for intelligent fault diagnosis. In this study, a turbine rotor fault diagnosis method based on the finite element method and transfer learning (FEMATL) is proposed, ensuring that the intelligent model can maintain high diagnostic accuracy in the case of insufficient samples. This method fully exploits the finite element method (FEM) and transfer learning (TL) for small-sample problems. First, FEM is used to generate data samples with fault information, and then the one-dimensional vibration displacement signal is transformed into a two-dimensional time-frequency diagram (TFD) by taking advantage of the deep learning model to recognize the image. Finally, a pre-trained ResNet18 network was used as the input to carry out transfer learning. The feature extraction layer of the network was trained on the ImageNet dataset and a fully connected layer was used to match the specific classification problems. The experimental results show that the method requires only a small amount of training data to achieve high diagnostic accuracy and significantly reduces the training time.

9.
PLoS One ; 19(1): e0297139, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38277415

RESUMEN

In flexible job shop scheduling problem (FJSP), the collision of bidirectional rail guided vehicles (RGVs) directly affects RGVs scheduling, and it is closely coupled with the allocation of production equipment, which directly affects the production efficiency. In this problem, taking minimizing the maximum completion time of RGVs and minimizing the maximum completion time of products as multi-objectives a dual-resource integrated scheduling model of production equipment and RGVs considering conflict-free routing problem (CFRP) is proposed. To solve the model, a multi-objective improved discrete grey wolf optimizer (MOID-GWO) is designed. Further, the performance of popular multi-objective evolutionary algorithms (MOEAs) such as NSGA-Ⅱ, SPEA2 and MOPSO are selected for comparative test. The results show that, among 42 instances of different scales designed, 37, 34 and 28 instances in MOID-GWO are superior to the comparison algorithms in metrics of generational distance (GD), inverted GD (IGD) and Spread, respectively. Moreover, in metric of Convergence and Diversity (CD), the Pareto frontier (PF) obtained by MOID-GWO is closer to the optimal solution. Finally, taking the production process of a construction machinery equipment component as an example, the validity and feasibility of the model and algorithm are verified.


Asunto(s)
Algoritmos , Evolución Biológica , Benchmarking
10.
J Nanosci Nanotechnol ; 13(3): 2262-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23755676

RESUMEN

LiMn2O4 nanoparticles were prepared by solid state reaction with nano-size Mn3O4 precursor. Mn3O4 nanoparticles with the size of about 200 nm were prepared via controlled crystallization method, which were used as the precursor to prepare LiMn2O4 in nanometer size. The size of LiMn2O4 synthesized by the route is about 300 nm. Cyclic voltammetry shows two pairs of clearly-separated oxidation peaks, located at 4.07 and 4.19 V, and reduction peaks, located at 3.91 and 4.07 V. The as-synthesized LiMn2O4 nanoparticles exhibit good electrochemical performance with an initial discharge capacity of 125.9 mAh x g(-1) at a current density of 14.8 mA x g(-1). The LiMn2O4 nanoparticles show wonderful cycle ability and the capacity retention ratio is 92.1% after 650 cycles at the current density of 296 mA x g(-1).

11.
Math Biosci Eng ; 20(8): 15265-15308, 2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37679180

RESUMEN

In the intelligent manufacturing environment, modern industry is developing at a faster pace, and there is an urgent need for reasonable production scheduling to ensure an organized production order and a dependable production guarantee for enterprises. Additionally, production cooperation between enterprises and different branches of enterprises is increasingly common, and distributed manufacturing has become a prevalent production model. In light of these developments, this paper presents the research background and current state of distributed shop scheduling. It summarizes relevant research on issues that align with the new manufacturing model, explores hot topics and concerns and focuses on the classification of distributed parallel machine scheduling, distributed flow shop scheduling, distributed job shop scheduling and distributed assembly shop scheduling. The paper investigates these scheduling problems in terms of single-objective and multi-objective optimization, as well as processing constraints. It also summarizes the relevant optimization algorithms and their limitations. It also provides an overview of research methods and objects, highlighting the development of solution methods and research trends for new problems. Finally, the paper analyzes future research directions in this field.

12.
Biomimetics (Basel) ; 8(8)2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38132544

RESUMEN

In the realm of industrial robotics, there is a growing challenge in simplifying human-robot collaboration (HRC), particularly in complex settings. The demand for more intuitive teleoperation systems is on the rise. However, optimizing robot control interfaces and streamlining teleoperation remains a formidable task due to the need for operators to possess specialized knowledge and the limitations of traditional methods regarding operational space and time constraints. This study addresses these issues by introducing a virtual reality (VR) HRC system with five-dimensional capabilities. Key advantages of our approach include: (1) real-time observation of robot work, whereby operators can seamlessly monitor the robot's real-time work environment and motion during teleoperation; (2) leveraging VR device capabilities, whereby the strengths of VR devices are harnessed to simplify robot motion control, significantly reducing the learning time for operators; and (3) adaptability across platforms and environments: our system effortlessly adapts to various platforms and working conditions, ensuring versatility across different terminals and scenarios. This system represents a significant advancement in addressing the challenges of HRC, offering improved teleoperation, simplified control, and enhanced accessibility, particularly for operators with limited prior exposure to robot operation. It elevates the overall HRC experience in complex scenarios.

13.
Proc Natl Acad Sci U S A ; 106(50): 21230-5, 2009 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19955425

RESUMEN

Due to its numerous environmental extremes, the Tibetan Plateau--the world's highest plateau--is one of the most challenging areas of modern human settlement. Archaeological evidence dates the earliest settlement on the plateau to the Late Paleolithic, while previous genetic studies have traced the colonization event(s) to no earlier than the Neolithic. To explore whether the genetic continuity on the plateau has an exclusively Neolithic time depth, we studied mitochondrial DNA (mtDNA) genome variation within 6 regional Tibetan populations sampled from Tibet and neighboring areas. Our results confirm that the vast majority of Tibetan matrilineal components can trace their ancestry to Epipaleolithic and Neolithic immigrants from northern China during the mid-Holocene. Significantly, we also identified an infrequent novel haplogroup, M16, that branched off directly from the Eurasian M founder type. Its nearly exclusive distribution in Tibetan populations and ancient age (>21 kya) suggest that M16 may represent the genetic relics of the Late Paleolithic inhabitants on the plateau. This partial genetic continuity between the Paleolithic inhabitants and the contemporary Tibetan populations bridges the results and inferences from archaeology, history, and genetics.


Asunto(s)
Emigración e Inmigración , Genoma Mitocondrial/genética , Paleontología , Secuencia de Bases , China , Efecto Fundador , Variación Genética , Historia Antigua , Humanos , Datos de Secuencia Molecular , Tibet
14.
ACS Appl Mater Interfaces ; 13(37): 45068-45076, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34510893

RESUMEN

Ni-rich layered oxides have become the main force of cathode materials for EV cells with high energy density owing to their satisfactory theoretical capacity, cost-effectiveness, and low toxicity. However, the high-voltage stability of Ni-rich cathode materials still has not fulfilled the demand of power batteries due to their intrinsic structural and electrochemical instability. The commonly used modification procedures are achieved via a wet process, which may lead to surface lithium-ion deficiency, phase change, and high costs during manufacturing. Herein, we construct a multifunctional Ti-based interfacial architecture on the surface of LiNi0.6Co0.2Mn0.2O2 (NCM) cathode materials via a novel dry interface modifying process in which no solvent is employed. The Ti-based interfacial architecture accelerates the transportation of lithium ions and consequently stabilizes the interfacial structure. This approach significantly improves the cycling stability in half cells, with a 15% increase in capacity retention over 100 cycles at 1 C under a high voltage of 4.5 V. Impressively, few internal cracks are observed in a modified sample after 500 times of charge and discharge between 2.75 and 4.35 V at 1 C rate, and the capacity retention can reach 93%.

15.
ACS Omega ; 6(21): 13601-13610, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34095654

RESUMEN

A novel solar energy storage heating radiator (SESHR) prototype filled with low-temperature phase change material (PCM) has been developed to accommodate the urgent demand in thermal storage and the fluctuation in renewable energy utilization. This equipment integrated by several independent heat storage units (HSUs) and water and paraffin wax was used as a heat transfer fluid and an energy storage material, respectively. The experimental test platform for low-temperature SESHR was designed and established. The total storage/dissipation time, average storage/dissipation capacity, and the rate and overall thermal efficiency were investigated under different operating conditions. Experimental results showed that a higher temperature difference between the heat source and the melting point of the PCM could significantly improve the heat storage capacity and rate. The heat dissipation rate of the SESHR could be controlled by adjusting the opening ratio of the air convective channel. The average storage rate of the SESHR with 2#PCM reached 1106 W at a heat source temperature of 85 °C, and the average heat dissipation rate reached 80.7 W at 100% opening ratio when the SESHR was filled with 1#PCM.

16.
Sci Prog ; 103(4): 36850420967858, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33208048

RESUMEN

Semi-built-up crankshafts are universally manufactured by shrink-fitting process with induction heating device. The configurations of induction coil have a great impact on the distributions of eddy current and temperature of crankthrows. Most induction devices are apt to cause some undesirable phenomena such as uneven temperature distribution and irregular deformation after induction heating. This article proposes a modified configuration of induction heating coil according to the crankthrow geometry. By combining the heat conduction equation and the heat boundary conditions, a three-dimensional finite element model, which takes into account the nonlinearity of the material's electromagnetic and thermal physical properties in the heating process, was developed. The influence of several parameters, such as position and curvature of the arc coil, the current frequency and density, coaxiality of crankweb hole and coil, influencing the temperature distribution inside the crankthrow was also analyzed. The comparison with the numerical simulation results of the original configuration indicates that the modified configuration has better adaptability to the crankthrow. Also, it can help to improve the temperature distribution, and reduce the deformation of the shrink-fitting hole. This exploration provide an effective way for the enterprise to further enhance the shrink-fitting quality of crankshaft.

17.
Waste Manag ; 103: 52-60, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31865035

RESUMEN

Herein, a novel process involving ultrasound-assisted leaching developed for recovering Ni, Li, Co, and Mn from spent lithium-ion batteries (LIBs) is reported. Carbonate coprecipitation was utilized to regenerate LiNi0.6Co0.2Mn0.2O2 from the leachate. Spent cathode materials were leached in DL-malic acid and hydrogen peroxide (H2O2). The leaching efficiency was investigated by determining the contents of metal elements such as Li, Ni, Co, and Mn in the leachate using atomic absorption spectrometry (AAS). The filter residue and the spent cathode materials were examined using Fourier transform infrared (FTIR) and scanning electronic microscopy. The leaching efficiencies were 97.8% for Ni, 97.6% for Co, 97.3% for Mn, and 98% for Li under the optimized conditions (90 W ultrasound power, 1.0 mol/L DL-malic acid, 5 g/L pulp density, 80 °C, 4 vol% H2O2, and 30 min). The leaching kinetics of the cathode in DL-malic acid are in accordance with the log rate law model. The electrochemical analysis indicates that the LiNi0.6Co0.2Mn0.2O2 regenerated at pH 8.5 has good electrochemical performance. The specific capacity of the first discharge at 0.1 C is 168.32 mA h g-1 at 1 C after 50 cycles with a capacity retention of 85.0%. A novel closed-loop process to recycle spent cathode materials was developed, and it has potential value for practical application and for contributing to resource recycling and environmental protection.


Asunto(s)
Peróxido de Hidrógeno , Litio , Suministros de Energía Eléctrica , Electrodos , Malatos , Reciclaje
18.
ChemSusChem ; 13(4): 803-810, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-31756020

RESUMEN

The morphology and size of nanoelectrode materials determine their properties. Compared to the bulk structure electrodes, 1 D electrode materials for Li-ion batteries have been intensively studied owing to their excellent Li+ diffusion kinetics. It is generally accepted that smaller-sized electrode materials lead to better Li storage kinetics. In this study, this is found to not be the case in 1 D LiMn2 O4 positive materials. A facile strategy of manipulating the KMnO4 concentration is introduced to precisely fabricate 1 D LiMn2 O4 nanorods with four distinct diameter gradients from 30 to 170 nm. The role of 1 D crystal size in effecting interface chemical species and electrochemical performance is elucidated by comparative characterization methods. X-ray photoelectron spectroscopy (XPS) Ar-ion etching technology shows that the Mn2+ is electrochemically inactive on the surface of the sample, which explains the adverse effects observed on LiMn2 O4 nanorods with the minimum diameter of 30-40 nm, such as decreased discharge capacity. The LiMn2 O4 nanorod with a critical diameter of approximately 70-80 nm displays the highest discharge capacity and promising cycling performance. This work clarifies an important property that has previously been neglected and deepens the understanding for design of Mn-based positive materials.

19.
Waste Manag ; 78: 51-57, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32559940

RESUMEN

An effective and environmentally friendly recycling process designed for LiCoO2 cathode powders of spent Li-ion batteries using mixture of mild organic acids, citric acid (CA), tartaric acid (TA) and ascorbic acid (AA), to recover the metals. Almost complete dissolution of Li and nearly 90% dissolution of Co occurred in at 80 °C for 6 h. The reducing agent, ascorbic acid (AA), converts the dissolved Co(III) to Co(II) thereby selective recovery of Co as Co(II)-oxalate is possible. The formation of Co(III)-and Co(II) complex is evident from the UV-Vis spectra of the dissolved solution as a function of dissolution time. Thus, the reductive-complexing dissolution mechanism is proposed here. These mild organic acids are environmentally benign unlike the mineral acids.

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