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1.
Artículo en Inglés | MEDLINE | ID: mdl-39262374

RESUMEN

Conductive hydrogels have been increasingly employed to construct wearable mechanosensors due to their excellent mechanical flexibility close to that of soft tissues. In this work, piezoelectric hydrogels are prepared through free radical copolymerization of acrylamide (AM) and acrylonitrile (AN) and further utilized in assembling flexible wearable mechanosensors. Introduction of the polyacrylonitrile (PAN) component in the copolymers endows the hydrogels with excellent piezoelectric properties. Meanwhile, significant enhancement of mechanical properties has been accessed by forming dipole-dipole interactions, which results in a tensile strength of 0.51 MPa. Flexible wearable mechanosensors are fabricated by utilizing piezoelectric hydrogels as key signal converting materials. Self-powered piezoelectric pressure sensors are assembled with a sensitivity (S) of 0.2 V kPa-1. Additionally, resistive strain sensors (gauge factor (GF): 0.84, strain range: 0-250%) and capacitive pressure sensors (S: 0.23 kPa-1, pressure range: 0-8 kPa) are fabricated by utilizing such hydrogels. These flexible wearable mechanosensors can monitor diverse body movements such as joint bending, walking, running, and stair climbing. This work is anticipated to offer promising soft materials for efficient mechanical-to-electrical signal conversion and provides new insights into the development of various wearable mechanosensors.

2.
Sci Rep ; 14(1): 10741, 2024 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730036

RESUMEN

The majority of pigeon paramyxovirus type 1 (PPMV-1) strains are generally non-pathogenic to chickens; however, they can induce severe illness and high mortality rates in pigeons, leading to substantial economic repercussions. The genomes of 11 PPMV-1 isolates from deceased pigeons on meat pigeon farms during passive monitoring from 2009 to 2012 were sequenced and analyzed using polymerase chain reaction and phylogenetic analysis. The complete genome lengths of 11 isolates were approximately 15,192 nucleotides, displaying a consistent gene order of 3'-NP-P-M-F-HN-L-5'. ALL isolates exhibited the characteristic motif of 112RRQKRF117 at the fusion protein cleavage site, which is characteristic of velogenic Newcastle disease virus. Moreover, multiple mutations have been identified within the functional domains of the F and HN proteins, encompassing the fusion peptide, heptad repeat region, transmembrane domains, and neutralizing epitopes. Phylogenetic analysis based on sequences of the F gene unveiled that all isolates clustered within genotype VI in class II. Further classification identified at least two distinct sub-genotypes, with seven isolates classified as sub-genotype VI.2.1.1.2.2, whereas the others were classified as sub-genotype VI.2.1.1.2.1. This study suggests that both sub-genotypes were implicated in severe disease manifestation among meat pigeons, with sub-genotype VI.2.1.1.2.2 displaying an increasing prevalence among Shanghai's meat pigeon population since 2011. These results emphasize the value of developing pigeon-specific vaccines and molecular diagnostic tools for monitoring and proactively managing potential PPMV-1 outbreaks.


Asunto(s)
Columbidae , Genoma Viral , Enfermedad de Newcastle , Virus de la Enfermedad de Newcastle , Filogenia , Animales , Columbidae/virología , China/epidemiología , Virus de la Enfermedad de Newcastle/genética , Virus de la Enfermedad de Newcastle/aislamiento & purificación , Virus de la Enfermedad de Newcastle/clasificación , Enfermedad de Newcastle/virología , Enfermedad de Newcastle/epidemiología , Genotipo , Granjas , Carne/virología
3.
Small ; : e2312124, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751072

RESUMEN

Rechargeable metal batteries have received widespread attention due to their high energy density by using pure metal as the anode. However, there are still many fundamental problems that need to be solved before approaching practical applications. The critical ones are low charge/discharge current due to slow ion transport, short cycle lifetime due to poor anode/cathode stability, and unsatisfied battery safety. To tackle these problems, various strategies have been suggested. Among them, electrolyte additive is one of the most widely used strategies. Most of the additives currently studied are soluble, but their reliability is questionable, and they can easily affect the electrochemical process, causing unwanted battery performance decline. On the contrary, insoluble additives with excellent chemical stability, high mechanical strength, and dimensional tunability have attracted considerable research exploration recently. However, there is no timely review on insoluble additives in metal batteries yet. This review summarizes various functions of insoluble additives: ion transport modulation, metal anode protection, cathode amelioration, as well as battery safety enhancement. Future research directions and challenges for insoluble solid additives are also proposed. It is expected this review will stimulate inspiration and arouse extensive studies on further improvement in the overall performance of metal batteries.

4.
J Colloid Interface Sci ; 662: 976-985, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38382380

RESUMEN

Thermosensitive hydrogels have found extensive applications in soft devices, but they often suffer from limited functionalities, low response rate and small response amplitude. In this work, double layered asymmetrical hydrogels composed of a thermosensitive layer and a non-thermosensitive layer are developed to simultaneously achieve high-performance mechanosensing and actuating properties in a single hydrogel. In thermosensitive layer, thermosensitive microgels are introduced to construct hierarchical structure, which accounts for the enhanced thermosensitive behaviors by cooperative responsiveness. In non-thermosensitive layer, poly(acrylamide-co-acrylic acid) (P(AM-co-AA)) hydrogel is constructed. KCl is introduced as conductive component. Mechanosensors for monitoring various mechanical stimuli in daily life have been fabricated utilizing such hydrogels and high gauge factors (GF) have been achieved, 0.38 for resistive strain sensors, 9.40 kPa-1 for piezoresistive pressure sensors and 3.92 kPa-1 for capacitive pressure sensors. Because of the asymmetrical structure, such hydrogels also exhibit outstanding actuating properties with a fast response rate of 863°/min and a bending amplitude about 360°. Interestingly, grasping-releasing of target objects utilizing an octopus-shaped hydrogel actuator and temperature alerting based on hydrogel actuator are also demonstrated. Overall, the double layered asymmetrical ionic hydrogels have provided a new clue to construct hydrogel devices with multiple functionalities and enhanced response properties.

5.
ACS Omega ; 9(1): 1134-1142, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38222537

RESUMEN

We have reported the synthesis of epitope-imprinted mesoporous silica (EIMS) with an average pore size of 6.2 nm, which is similar to the geometrical size of the target protein, cytochrome C (Cyt c, 2.6 × 3.2 × 3.3 nm3), showing great recognition and large-scale adsorption performance. The characteristic fragment of Cyt c was used as a template and docked onto the surface of C16MIMCl micelles via multiple interactions. Nitrogen adsorption-desorption and transmission electron microscopy confirmed the successful preparation of EIMS. Due to the ordered pore structure, larger pore size, and high specific surface area, the prepared EIMS show superior specificity (IF = 3.8), excellent selectivity toward Cyt c, high adsorption capacity (249.6 mg g-1), and fast adsorption equilibrium (10 min). This study demonstrates the potential application of EIMS with a controllable pore size for high-effective and large-scale separation of Cyt c, providing a new approach for effective biomacromolecular recognition.

6.
J Occup Environ Hyg ; 21(2): 108-118, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37812187

RESUMEN

The application and removal of personal protective equipment (PPE) by health care workers (HCWs) is pivotal to their health and safety and the comprehensive efficacy of hospital infection control measures. This investigation was orchestrated to elucidate the challenges that HCWs may encounter during the donning and doffing of PPE. A total of 110 participants from a tertiary hospital in China were engaged. The study employed fluorescent markers to mimic the exposure of HCWs to tainted body fluids, quantified the contamination outcomes, and evaluated adherence to procedures for donning and doffing. Factors including gender, educational background, and the timing of the most recent instruction on PPE donning and doffing were found to influence the occurrence of contamination points (p < 0.05). No significant differences were identified in contamination frequency when assessing age, body mass index (BMI), occupation, educational background, positional title, working tenure, and experience in managing respiratory infectious diseases (p > 0.05). Predominant contamination sites for fluorescent marker residue included the shoulder (32.73%), neck (21.82%), forearm (16.36%), chest (12.73%), and abdomen (11.82%), with the shoulder being the most contaminated body part. A majority of HCWs exhibited susceptibility to errors during the removal of protective clothing, boot covers, and gloves. The contamination frequency was observed to be correlated with the timing of the last PPE training, educational background, and gender. In acknowledging the intricacy of PPE removal and the deficiencies in HCWs' removal techniques, there emerges a perpetual necessity to refine training methodologies and perpetuate regular PPE instruction.


Asunto(s)
Fiebre Hemorrágica Ebola , Dispositivos de Protección Respiratoria , Humanos , Centros de Atención Terciaria , Guantes Protectores , Transmisión de Enfermedad Infecciosa de Paciente a Profesional , Equipo de Protección Personal , Personal de Salud/educación , China
7.
Angew Chem Int Ed Engl ; 63(4): e202316904, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38059793

RESUMEN

Aqueous zinc ion batteries are gaining popularity due to their high energy density and environmental friendliness. However, random deposition of zinc ions on the anode and sluggish migration of zinc ions on the interface would lead to the growth of zinc dendrites and poor cycling performance. To address these challenges, we developed a fluorinated solid-state-electrolyte interface layer composed of Ca5 (PO4 )3 F/Zn3 (PO4 )2 via an in situ ion exchange strategy to guide zinc-ion oriented deposition and fast zinc ion migration on the anode during cycling. The introduction of Ca5 (PO4 )3 F (FAP) can increase the nucleation sites of zinc ions and guide the oriented deposition of zinc ions along the (002) crystal plane, while the in situ formation of Zn3 (PO4 )2 during cycling can accelerate the migration of zinc ions. Benefited from our design, the assembled Zn//V2 O5 ⋅ H2 O batteries based on FAP-protected Zn anode (FAP-Zn) achieve a higher capacity retention of 84 % (220 mAh g-1 ) than that of bare-Zn based batteries, which have a capacity retention of 23 % (97 mAh g-1 ) at 3.0 A g-1 after 800 cycles. This work provides a new solution for the rational design and development of the solid-state electrolyte interface layer to achieve high-performance zinc-ion batteries.

8.
Micromachines (Basel) ; 14(8)2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37630035

RESUMEN

This study examines the impact of surface defects on the electro-explosive properties of metal explosive foil transducers. Specifically, it focuses on the effects of defects in the bridge foil and their influence on the electrical explosion time and transduction efficiency. To analyze these effects, a current-voltage simulation model is developed to simulate the behavior of a defective bridge foil. The simulation results are validated through experimental current-voltage measurements at both ends of the bridge area. The findings reveal that the presence of through-hole defects on the surface of the bridge foil leads to an advancement in the electrical explosion time and a reduction in the transduction efficiency of the bridge foil. A performance comparison is made between the defective bridge foil and a defect-free copper foil. As observed, a through-hole defect with a radius of 20 µm results in a 1 ns advance in the blast time and a 1.52% decrease in energy conversion efficiency. Similarly, a through-hole defect with a radius of 50 µm causes a 51 ns advancement in the blast time and a 13.96% reduction in the energy conversion efficiency. These findings underscore the detrimental effects of surface defects on the electro-explosive properties, emphasizing the importance of minimizing defects to enhance their performance.

9.
Mater Horiz ; 10(9): 3680-3693, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37365987

RESUMEN

Aqueous zinc-ion batteries (ZIBs) are promising candidates for next-generation energy storage systems due to their intrinsic safety, environmental friendliness, and low cost. However, the uncontrollable Zn dendrite growth during cycling is still a critical challenge for the long-term operation of ZIBs, especially under harsh lean-Zn conditions. Herein, we report nitrogen and sulfur-codoped carbon quantum dots (N,S-CDs) as zincophilic electrolyte additives to regulate the Zn deposition behaviors. The N,S-CDs with abundant electronegative groups can attract Zn2+ ions and co-deposit with Zn2+ ions on the anode surface, inducing a parallel orientation of the (002) crystal plane. The deposition of Zn preferentially along the (002) crystal direction fundamentally avoids the formation of Zn dendrites. Moreover, the co-depositing/stripping feature of N,S-CDs under an electric field force ensures the reproducible and long-lasting modulation of the Zn anode stability. Benefiting from these two unique modulation mechanisms, stable cyclability of the thin Zn anodes (10 and 20 µm) at a high depth of discharge (DOD) of 67% and high Zn||Na2V6O16·3H2O (NVO, 11.52 mg cm-2) full-cell energy density (144.98 W h Kg-1) at a record-low negative/positive (N/P) capacity ratio of 1.05 are achieved using the N,S-CDs as an additive in ZnSO4 electrolyte. Our findings not only offer a feasible solution for developing actual high-energy density ZIBs but also provide in-depth insights into the working mechanism of CDs in regulating Zn deposition behaviors.

10.
Talanta ; 261: 124617, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37187026

RESUMEN

A novel immobilized metal affinity chromatography (IMAC) functional composite, mNi@N-GrT@PDA@Ti4+, was fabricated based on ultrathin magnetic nitrogen-doped graphene tube (mNi@N-GrT) after chelated Ti4+ with polydopamine, following as a magnetic solid-phase extraction sorbent for rapidly selective enrichment and mass spectrometry identification of phosphorylated peptides. After optimized, the composite exhibited high specificity in the enrichment of phosphopeptides from the digest mixture of ß-casein and bovine serum albumin (BSA). The robust method presented the low detection limits (1 fmol, 200 µL) and excellent selectivity (1:100) in the molar ration mixture of ß-casein and BSA digests. Furthermore, the selective enrichment of phosphopeptides in the complex bio-samples, was successfully carried out. The results showed that 28 phosphopeptides were finally detected in mouse brain, and 2087 phosphorylated peptides were identified in the HeLa cells extracts with specific selectivity of 95.6%. The enrichment performance of mNi@N-GrT@PDA@Ti4+ was satisfactory, suggesting that the functional composite provided a potential application in the enrichment of trace phosphorylated peptides from the complex biological matrix.


Asunto(s)
Grafito , Fosfopéptidos , Humanos , Animales , Ratones , Fosfopéptidos/análisis , Caseínas/química , Grafito/química , Titanio/química , Células HeLa , Albúmina Sérica Bovina/química , Cromatografía de Afinidad/métodos
11.
Small ; 19(23): e2207093, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36890773

RESUMEN

Lithium metal batteries (LMBs) are promising for next-generation high-energy-density batteries owing to the highest specific capacity and the lowest potential of Li metal anode. However, the LMBs are normally confronted with drastic capacity fading under extremely cold conditions mainly due to the freezing issue and sluggish Li+ desolvation process in commercial ethylene carbonate (EC)-based electrolyte at ultra-low temperature (e.g., below -30 °C). To overcome the above challenges, an anti-freezing carboxylic ester of methyl propionate (MP)-based electrolyte with weak Li+ coordination and low-freezing temperature (below -60 °C) is designed, and the corresponding LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) cathode exhibits a higher discharge capacity of 84.2 mAh g-1 and energy density of 195.0 Wh kg-1 cathode than that of the cathode (1.6 mAh g-1 and 3.9 Wh kg-1 cathode ) working in commercial EC-based electrolytes for NCM811‖ Li cell at -60 °C. Molecular dynamics simulation, Raman spectra, and nuclear magnetic resonance characterizations reveal that rich mobile Li+ and the unique solvation structure with weak Li+ coordination are achieved in MP-based electrolyte, which collectively facilitate the Li+ transference process at low temperature. This work provides fundamental insights into low-temperature electrolytes by regulating solvation structure, and offers the basic guidelines for the design of low-temperature electrolytes for LMBs.

12.
Environ Sci Pollut Res Int ; 30(9): 23747-23763, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36327079

RESUMEN

As a core driver for the high-tech enterprises, green technology innovation is crucial, even with high financial risk. Against this background, this paper empirically examines the impact of risk-taking on green technology innovation of high-tech enterprises, taking Chinese A-share listed companies from 2007 to 2020 as the research sample and considering the moderating effect of financial mismatch. Findings show the following: First, the effect of risk-taking on green technology innovation of high-tech enterprises is insignificant in most cases, and the inhibitory effect of financial mismatch is partly supported. Second, financial mismatch only counter-regulates the inhibitory effect of systematic risk-taking on the number of invention patents granted in the eastern sample. Third, the effect of risk-taking on green technology innovation is significantly heterogeneous in terms of property rights and regional heterogeneity, regardless of considering the moderating effect of financial mismatch or not. Finally, the policy implementations point out that the government should create a favorable investment environment, financial institutions should adjust the way of capital allocation, while high-tech enterprises should broaden the financing channels to enhance their risk-taking ability, and promote green technological innovation to achieve high-quality economic development.


Asunto(s)
Desarrollo Económico , Invenciones , Tecnología , China , Asunción de Riesgos
13.
Curr Biol ; 32(24): 5235-5249.e7, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-36402137

RESUMEN

Increasing nitrogen (N) deposition often tends to negatively impact the functions of belowground ectomycorrhizal networks, although the exact molecular mechanisms underlying this trait are still unclear. Here, we assess how the root-associated fungus Clitopilus hobsonii establishes an ectomycorrhiza-like association with its host tree Populus tomentosa and how this interaction is favored by organic N over mineral N. The establishment of a functional symbiosis in the presence of organic N promotes plant growth and the transfer of 15N from the fungus to above ground plant tissues. Genomic traits and in planta transcriptional signatures suggest that C. hobsonii may have a dual lifestyle with saprotrophic and mutualistic traits. For example, several genes involved in the digestion of cellulose and hemicellulose are highly expressed during the interaction, whereas the expression of multiple copies of pectin-digesting genes is tightly controlled. Conversely, the nutritional mutualism is dampened in the presence of ammonium (NH4+) or nitrate (NO3-). Increasing levels of NH4+ led to a higher expression of pectin-digesting genes and a continuous increase in hydrogen peroxide production in roots, whereas the presence of NO3- resulted in toxin production. In summary, our results suggest that C. hobsonii is a facultative ectomycorrhizal fungus. Access to various forms of N acts as an on/off switch for mutualism caused by large-scale fungal physiological remodeling. Furthermore, the abundance of pectin-degrading enzymes with distinct expression patterns during functional divergence after exposure to NH4+ or organic N is likely to be central to the transition from parasitism to mutualism.


Asunto(s)
Compuestos de Amonio , Micorrizas , Micorrizas/fisiología , Nitrógeno/metabolismo , Simbiosis , Nitratos , Compuestos de Amonio/metabolismo , Raíces de Plantas/metabolismo
14.
Front Cell Dev Biol ; 10: 942225, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36003146

RESUMEN

Pancreatic adenocarcinoma (PAAD) is one of the deadliest malignancies. Aging is described as the degeneration of physiological function, which is complexly correlated with cancer. It is significant to explore the influences of aging-related genes (ARGs) on PAAD. Based on The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) datasets, we used univariate Cox regression analysis and acquired eight differentially expressed ARGs with prognostic values. Two molecular subtypes were identified based on these ARGs to depict PAAD patients' overall survival (OS) and immune microenvironments preliminarily. Cluster 1 had a poor OS as well as a worse immune microenvironment. Through least absolute shrinkage and selection operator (LASSO) regression analysis, we constructed a seven-ARG risk signature based on the TCGA dataset and verified it in Gene Expression Omnibus (GEO) and International Cancer Genome Consortium (ICGC) to predict the prognoses, immune microenvironments, signal pathways, tumor mutations, and drug sensitivity of PAAD patients. The high-risk group possessed an unfavorable OS compared with that of the low-risk group. We also verified the independence and clinical availability of the risk signature by Cox regression analyses and the establishment of a nomogram, respectively. The higher risk score was associated with several clinical factors such as higher grade and advanced tumor stage as well as lower immunoscore and cluster 1. The negative associations of risk scores with immune, stroma, and estimate scores proved the terrible immune microenvironment in the high-risk group. Relationships between risk score and immune checkpoint gene expression as well as signal pathways provided several therapeutic targets. PAAD patients in the low-risk group possessed lower tumor mutations as well as a higher susceptibility to axitinib and vorinostat. The high-risk group bore a higher TMB and cisplatin and dasatinib may be better options. We used immunohistochemistry and qPCR to confirm the expression of key ARGs with their influences on OS. In conclusion, we identified two ARG-mediated molecular subtypes and a novel seven-ARG risk signature to predict prognoses, immune microenvironments, signal pathways, tumor mutations, and drug sensitivity of PAAD patients.

15.
Micromachines (Basel) ; 13(6)2022 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-35744468

RESUMEN

Laser shaping technology and its applications have gained widespread attention in different fields. Using laser repair technology prolongs the service life of micro-explosive products and reduces the production cost, as well as enables the recycling of resources. Although most research mainly focuses on aspheric surface shaping and testing technology, only a few studies on repair technology for micro-explosive products using laser shaping have been reported. To promote the better application of laser shaping technology in the production and repair process of micro-explosive components, this work mainly studied the effect of laser shaping on the repair of an explosive bridge film to enhance the ignition performance and prevent damage. Different processes were used to repair the metal film using laser shaping and non-shaping, respectively. Furthermore, we investigated the similarities and differences of a laser-damaged film surface before and after shaping, and the influence of laser energy parameters on the microstructure and ignition properties of the repaired region. Additionally, we obtained a reasonable repair scheme by analyzing the temperature field variation from the simulation. The results show that the damage caused by the non-shaping and shaping lasers can be repaired using the heat flow and vaporization methods, respectively. By controlling the process parameters, the quality of repair can be improved and the production cost of the bridge film can be reduced.

16.
Dis Markers ; 2022: 5634887, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36618967

RESUMEN

Pancreatic cancer (PC) is a fatal tumor with high mortality. Pyroptosis plays a tumor suppressor role as a novel cell death. However, the influences of the pyroptosis-related lncRNAs (PRlncRNAs) on the prognosis and tumor microenvironment (TME) infiltration have not been fully studied in PC. Using coexpression analysis and univariate Cox regression analysis, we identified seventeen prognostic PRlncRNAs from The Cancer Genome Atlas (TCGA) dataset, which were all expressed differently in normal and tumor samples. A seven-PRlncRNA risk signature was constructed and validated using the least absolute shrinkage and selection operator (LASSO) regression. Furthermore, we verified its independence and created a nomogram to validate the clinical viability of the risk signature. We then identified its relationship with clinical factors and evaluated its values in TME infiltration, functional enrichment, tumor mutation, and therapeutic responses in PC. Lower ImmuneScore, ESTIMATEScore, and advanced tumor stage were connected with high-risk score. The low-risk group was characterized by better OS, elevated immune activation, and higher susceptibility of pazopanib and sunitinib. The high-risk group possessed a worse immune infiltration and poor survival, with higher tumor mutations and lapatinib and paclitaxel that may be better choices in this group. In conclusion, we developed an original seven-PRlncRNA risk signature to predict prognosis, TME infiltration, tumor mutation, and therapeutic options for PC patients.


Asunto(s)
Neoplasias Pancreáticas , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Piroptosis/genética , Microambiente Tumoral/genética , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas
17.
Talanta ; 239: 123143, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34923255

RESUMEN

Chiral metal-organic frameworks (CMOFs) served as chiral stationary phases (CSPs) show great potential in enantioseparation field. However, their performance improvement are still hindered by the difficult column packed and high back pressure due to the irregular morphology and broad size scope of CMOF particles. Here, the size and morphology of achiral Co-MOF-74 were effectively adjusted by controlling the synthetic route, temperature, the ratio of reactants and the amount of 2-methylimidazole (2-MI) at first. As a result, the uniformly spherical crystals in size of about 5 µm with good dispersion were obtained. Subsequently, a simple, green post-synthetic modification strategy was proposed for the fabrication of l-tyrosine functionalized Co-MOF-74, namely Co-MOF-74-L-Tyr in H2O by incorporating l-tyrosine into the parent framework of Co-MOF-74 to construct chiral microenvironment. The homochiral Co-MOF-74-L-Tyr CSP gave superior enantioseparation performance for the eight chiral drugs and drug intermediates, such as nitrendipine, nimodipine, benzoin, 2,2'-furoin and bi-2-naphthol to the commercial columns under normal phase condition. The good repeatability and stability of this CSP was verified by the replicate enantioseparation for nimodipine and flavanone. Furthermore, the Co-MOF-74-L-Tyr packed column was successfully applied to detect the product N-1-(1-naphthyl)ethyltosylamide (HR-8) in the asymmetric reductive amination reaction. The size/morphology-controlled synthesis coupled with the green post-synthetic modification approach paves the way to fabricate target chiral MOFs with pre-designed functional groups, which is an effective complement for the preparation of CSPs in chiral chromatography.


Asunto(s)
Estructuras Metalorgánicas , Cromatografía Líquida de Alta Presión , Estereoisomerismo
18.
Small ; 17(43): e2103679, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34580989

RESUMEN

As one of the most efficient electrochemical energy storage devices, the energy density of lithium-ion batteries (LIBs) has been extensively improved in the past several decades. However, with increased energy density, the safety risk of LIBs becomes higher too. The frequently occurred battery accidents worldwide remind us that safeness is a crucial requirement for LIBs, especially in environments with high safety concerns like airplanes and military platforms. It is generally recognized that the catastrophic thermal runaway (TR) event is the major cause of LIBs related accidents. Tremendous efforts have been devoted to coping with the TR concerns in LIBs, and thus enhance battery safety. This review first gives an introduction to the fundamentals of LIBs and the origins of safety issues. Then, the authors summarize the recent advances to improve the safety of LIBs with a unique focus on thermal-responsive and fire-resistant materials. Finally, a perspective is proposed to guide future research directions in this field. It is anticipated this review will stimulate inspiration and arouse extensive studies on further improvement in battery safety.


Asunto(s)
Suministros de Energía Eléctrica , Litio , Iones
19.
Chem Commun (Camb) ; 57(80): 10343-10346, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34528980

RESUMEN

Herein, a rapid approach toward the size/morphology-controlled synthesis of [Cu(L-mal)(bipy)·2H2O] (CuLBH) was developed by adjusting the concentrations of 2-methylimidazole (2-MI) and copper ions. The chiral separation efficiency test indicated that the nano-diameter CuLBH exhibited better selective potential towards (±)-1-(1-naphthyl)ethanol (NE) by providing more fully exposed recognition sites. In order to further improve the selectivity for NE enantiomers and avoid the aggregation of MOF nanoparticles, the nanosized CuLBH-decorated carboxylated cellulose (CC) composite CC-CuLBH was designed by controlling the ratio of the solvent and Cu2+, which exhibited much higher enantioselectivity than those of pristine CC and even nano CuLBH.


Asunto(s)
Celulosa/química , Etanol/análogos & derivados , Estructuras Metalorgánicas/química , Nanopartículas/química , Naftalenos/aislamiento & purificación , Adsorción , Celulosa/síntesis química , Cobre/química , Etanol/química , Etanol/aislamiento & purificación , Estructuras Metalorgánicas/síntesis química , Naftalenos/química , Tamaño de la Partícula , Extracción en Fase Sólida , Estereoisomerismo
20.
Chemphyschem ; 22(16): 1675-1683, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34142761

RESUMEN

The unique physical structure and abundant surface functional groups of MXene make the grafted organic molecules exhibit specific electrical and optical properties. This work reports the results of first-principles calculations to investigate the composite systems formed by different organic molecular monomers, namely acrylic acid (AA), acrylamide (AM), 1-aziridineethanol (1-AD) and glucose, and Ti3 C2 MXene saturated with different functional groups, namely -OH, -O and -F. The results show that the interaction between organic molecules and the MXene surface depends on the type of functional groups of the organic molecules, while the strength of the interaction is determined by the type of surface functional groups and the number of hydrogen bonds. The bare Ti3 C2 and Ti3 C2 (OH)2 can readily form strong chemical and hydrogen bonds with AA and AM molecules, leading to strong adsorption energy and a large amount of charge transfer, while the interaction between organic molecules and MXene saturated by -F or -O groups mainly exhibits physical interactions, accompanied by low adsorption energy and a small amount of charge transfer. This research provides theoretical guidance for the synthesis of high-performance MXene organic composite systems.

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