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1.
Sci Rep ; 14(1): 8612, 2024 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616198

RESUMO

This study investigated the effects of Lactobacillus-fermented low-protein diet on the growth performance, nitrogen balance, fecal microbiota, and metabolomic profiles of finishing pigs. A total of 90 finishing pigs were assigned to one of three dietary treatments including a normal protein diet (CON) as well as two experimental diets in which a low-protein diet supplemented with 0 (LP) or 1% Lactobacillus-fermented low-protein feed (FLP). In comparison with CON, the LP and FLP significantly increased average daily gain (P = 0.044), significantly decreased feed to gain ratio (P = 0.021), fecal nitrogen (P < 0.01), urine nitrogen (P < 0.01), and total nitrogen (P < 0.01), respectively. The LP group exhibited increased abundances of unclassified_f_Selenomonadaceae, Coprococcus, Faecalibacterium, and Butyricicoccus, while the abundances of Verrucomicrobiae, Verrucomicrobiales, Akkermansiaceae, and Akkermansia were enriched in the FLP group. Low-protein diet-induced metabolic changes were enriched in sesquiterpenoid and triterpenoid biosynthesis and Lactobacillus-fermented low-protein feed-induced metabolic changes were enriched in phenylpropanoid biosynthesis and arginine biosynthesis. Overall, low-protein diet and Lactobacillus-fermented low-protein diet improved the growth performance and reduce nitrogen excretion, possibly via altering the fecal microbiota and metabolites in the finishing pigs. The present study provides novel ideas regarding the application of the low-protein diet and Lactobacillus-fermented low-protein diet in swine production.


Assuntos
Dieta com Restrição de Proteínas , Microbiota , Animais , Suínos , Metabolômica , Lactobacillus , Nitrogênio
2.
Appl Microbiol Biotechnol ; 108(1): 4, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38170312

RESUMO

The goal of this study was to characterize the fecal microbiota profiles of gestating sows, along with the fecal microbiota and milk fatty acid contents of lactating sows and their correlations with reproductive performance at different parities. The results showed that the microbiota of third parity gestating sows contained a greater abundance of Prevotella compared to the other two parity groups, while lactating sows exhibiting higher reproductive performance at fifth parity exhibited a greater abundance of Lactobacillus species. The lactating sows with higher reproductive performance also exhibited higher total monounsaturated fatty acid (MUFA) and higher total polyunsaturated fatty acid (PUFA) levels relative to sows with lower reproductive performance at all three analyzed parities, especially sows at fifth parity produced the lowest total saturated fatty acid (SFA) levels, and showed the highest C18:1n9c and C18:2n6c concentrations. In correlational analyses, the abundance of Oligella, Lactobacillus, and Corynebacterium was highly positively correlated with C18:1n9c, C18:2n6c, and C20:4n6. Overall, these results provide a rational basis for efforts to improve sow reproductive performance through the provision of precisely regulated nutrition. KEY POINTS: • Clear differences in the fecal microbiota were evident between sows of different parities. • Lactating sows with high reproductive performance showed distinct milk fatty acid profiles.


Assuntos
Microbiota , Leite , Gravidez , Feminino , Humanos , Animais , Lactação , Reprodução , Ácidos Graxos , Dieta/veterinária , Ração Animal/análise
3.
J Mol Graph Model ; 127: 108669, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38011826

RESUMO

Fragment-based drug design (FBDD) is one major drug discovery method employed in computer-aided drug discovery. Due to its inherent limitations, this process experiences long processing times and limited success rates. Here we present a new Fragment Databases from Screened Ligands Drug Design method (FDSL-DD) that intelligently incorporates information about fragment characteristics into a fragment-based design approach to the drug development process. The initial step of the FDSL-DD is the creation of a fragment database from a library of docked, drug-like ligands for a specific target, which deviates from the traditional in silico FBDD strategy, incorporating structure-based design screening techniques to combine the advantages of both approaches. Three different protein targets have been tested in this study to demonstrate the potential of the created fragment library and FDSL-DD. Utilizing the FDSL-DD led to an increase in binding affinity for each protein target. The most substantial increase was exhibited by the ligand designed for TIPE2, with a 3.6 kcalmol-1 difference between the top ligand from the FDSL-DD and top ligand from the high throughput virtual screening (HTVS). Using drug-like ligands in the initial HTVS allows for a greater search of chemical space, with higher efficiency in fragments selection, less grid boxes, and potentially identifying more interactions.


Assuntos
Desenho de Fármacos , Descoberta de Drogas , Ligantes , Descoberta de Drogas/métodos , Ensaios de Triagem em Larga Escala , Bases de Dados Factuais
4.
Front Psychiatry ; 14: 1254349, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034921

RESUMO

Introduction: Anxious individuals selectively attend to threatening information, but it remains unclear whether attentional bias can be generalized to traumatic events, such as the COVID-19 pandemic. Previous studies suggested that specific threats related to personal experiences can elicit stronger attentional bias than general threats. The current study aimed to investigate the relationship between content-specific attentional bias and trait anxiety during the COVID-19 pandemic. Methods: Attentional bias was assessed using the dot-probe task with COVID-19-related, general threat-related, and neutral words at two exposure times, 200 and 500 ms. Results: We found participants with high trait anxiety exhibited attentional bias toward COVID-19- related stimuli and attentional bias away from general threat-related stimuli, while participants with low trait anxiety showed attentional bias away from both types of stimuli. Discussion: Results suggest that individuals with high trait anxiety show a content-specific attentional bias to COVID-19-related information during the COVID-19 pandemic. Apart from the innate attentional bias toward biological threats, individuals with high trait anxiety may also learn from trauma and develop trauma-specific attentional bias.

5.
mSystems ; 8(6): e0098823, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38032191

RESUMO

IMPORTANCE: Our present study showed that dietary supplementation with feed fermented by Lactobacillus could promote the growth performance of pigs, regulate the microbiota, and inhibit the growth of harmful bacteria. It could prevent the accumulation of toxic substances and reduce odor emission from pig feces, thereby reducing environmental pollution. In addition, one key triumph of the present study was the isolation of Weissella cibaria ZWC030, and the strain could inhibit the production of skatole in vitro in our present results.


Assuntos
Lactobacillus , Microbiota , Suínos , Animais , Fermentação , Odorantes , Fezes/química
6.
Nat Commun ; 14(1): 4875, 2023 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573353

RESUMO

Clinical use of intraoperative auto-transfusion requires the removal of platelets and plasma proteins due to pump-based suction and water-soluble anticoagulant administration, which causes dilutional coagulopathy. Herein, we develop a carboxylated and sulfonated heparin-mimetic polymer-modified sponge with spontaneous blood adsorption and instantaneous anticoagulation. We find that intrinsic coagulation factors, especially XI, are inactivated by adsorption to the sponge surface, while inactivation of thrombin in the sponge-treated plasma effectively inhibits the common coagulation pathway. We show whole blood auto-transfusion in trauma-induced hemorrhage, benefiting from the multiple inhibitory effects of the sponge on coagulation enzymes and calcium depletion. We demonstrate that the transfusion of collected blood favors faster recovery of hemostasis compared to traditional heparinized blood in a rabbit model. Our work not only develops a safe and convenient approach for whole blood auto-transfusion, but also provides the mechanism of action of self-anticoagulant heparin-mimetic polymer-modified surfaces.


Assuntos
Anticoagulantes , Transtornos da Coagulação Sanguínea , Animais , Coelhos , Anticoagulantes/farmacologia , Fatores de Coagulação Sanguínea/metabolismo , Hemostasia , Heparina/farmacologia , Hemorragia/etiologia , Polímeros/farmacologia
7.
Eur J Pharmacol ; 957: 175961, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549730

RESUMO

Targeting HPV16 E6 has emerged as an effective drug target for the treatment/management of cervical cancer. We utilized pharmacophore-based virtual screening, molecular docking, absorption, distribution, metabolism and excretion (ADME) prediction, and molecular dynamics simulation approach for identifying potential inhibitors of HPV16 E6. Initially, we generated a ligand-based pharmacophore model based on the features of four known HPV16 E6 inhibitors (CA24, CA25, CA26, and CA27) via the PHASE module implanted in the Schrödinger suite. We constructed four-point pharmacophore features viz., three hydrogen bond acceptors (A) and one aromatic ring (R). The common pharmacophore feature further employed as a query for virtual screening against the ASINEX database via Schrödinger suite. The pharmacophore-based virtual screening filtered out top 2000 hits, based on the fitness score. We then applied the high throughput virtual screening (HTVS), standard precision (SP) and extra precision (XP). 1000 compounds were obtained from HTVS docking. Based on the glide score, they were further filtered to 500 hits by employing docking in standard precision mode. Finally, the best four hits and a negative molecule were identified using docking in XP mode. The four lead compounds and a negative molecule were then further subjected to ADME profile prediction by engaging Qikprop module. The ADME properties of the four lead molecules indicate good pharmacokinetic (PK) properties rather than the negative molecule. The binding stability of the HPV16 E6-hit complexes were investigated at a different time scale (100 ns) by using the desmond package and the results were examined using Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuation (RMSF) and it revealed the stability of the protein-ligand complex throughout the simulation. Key residues, CYS 51 and GLN 107, also play a crucial role in enhancing the stability of the protein-ligand complex during the simulation. Furthermore, the binding free energy of the HPV16 E6-leads complexes was analyzed by prime which revealed that the ΔGbind coulomb and ΔGbind vdW interactions are crucially contributes to the binding affinity. In order to validate the computational findings, the efficacy of benzoimidazole and benzotriazole were ascertained for regulating ME180 cervical cancer cell survival, migration and ability to release MMP-2.


Assuntos
Papillomavirus Humano 16 , Neoplasias do Colo do Útero , Humanos , Feminino , Simulação de Acoplamento Molecular , Ligação Proteica , Farmacóforo , Ligantes , Neoplasias do Colo do Útero/tratamento farmacológico , Detecção Precoce de Câncer
8.
Polymers (Basel) ; 15(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37447610

RESUMO

This research investigated a non-thermal, dielectric-barrier discharge (DBD) plasma-based approach to prepare poly(acrylic acid) (PAA) from acrylic acid in its liquid state at atmospheric temperature and pressure. Neither additives nor solvents were needed, and the polymerization was accomplished both as a film and inside a sheet of mesoporous paper. All prepared samples were characterized and the DBD plasma-initiated kinetics were analyzed for the polymerization of acrylic acid. Using FTIR semi-quantitative analysis, the degree of polymerization was monitored, and the reaction followed an overall second-order kinetic model with respect to the DBD-initiated polymerization. Additionally, the application of a PAA-modified paper as a water retention cloth or 'wet wipe' was investigated. The results showed that the PAA-modified paper substrates using DBD plasma increased water retention as a function of plasma treatment time.

9.
Sensors (Basel) ; 23(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37430800

RESUMO

Based on the principle of Contactless Conductivity Detection (CCD), a new contactless cross-correlation velocity measurement system with a three-electrode construction is developed in this work and applied to the contactless velocity measurement of gas-liquid two-phase flow in small channels. To achieve a compact design and to reduce the influence of the slug/bubble deformation and the relative position change on the velocity measurement, an electrode of the upstream sensor is reused as an electrode of the downstream sensor. Meanwhile, a switching unit is introduced to ensure the independence and consistency of the upstream sensor and the downstream sensor. To further improve the synchronization of the upstream sensor and the downstream sensor, fast switching and time compensation are also introduced. Finally, with the obtained upstream and downstream conductance signals, the velocity measurement is achieved by the principle of cross-correlation velocity measurement. To test the measurement performance of the developed system, experiments are carried out on a prototype with a small channel of 2.5 mm. The experimental results show that the compact design (three-electrode construction) is successful, and its measurement performance is satisfactory. The velocity range for the bubble flow is 0.312-0.816 m/s, and the maximum relative error of the flow rate measurement is 4.54%. The velocity range for the slug flow is 0.161 m/s-1.250 m/s, and the maximum relative error of the flow rate measurement is 3.70%.

10.
ACS Appl Mater Interfaces ; 15(31): 37845-37854, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37489898

RESUMO

Developing effective synthetic strategies as well as broadening functionalities for zwitterionic materials that comprise moieties with equimolar cationic and anionic groups still remains a huge challenge. Herein, we develop two zwitterionic vinylene-linked covalent organic frameworks (Zi-VCOF-1 and Zi-VCOF-2) that are a type of novel hydrophilic material. Zi-VCOF-1 and Zi-VCOF-2 are obtained directly through the convenient Knoevenagel condensation of new sulfonic-pyridinium zwitterionic monomers with aromatic aldehyde derivatives. This is the first report on zwitterionic COFs being constructed by the bottom-up functionalization approach from predesigned zwitterionic monomers. Both Zi-VCOFs exhibit a high photocatalytic hydrogen evolution rate (HER) because of their appropriate optical property and outstanding hydrophilicity. Specifically, Zi-VCOF-1 and Zi-VCOF-2 show photocatalytic HER of 13,547 and 5057 µmol h-1 g-1, respectively. Interestingly, the photocatalytic HER of Zi-VCOF-1 is about 2.68 times of that of Zi-VCOF-2, although they differ by only one methyl group in sulfonic-pyridinium zwitterionic pairs. The photocatalytic HER of Zi-VCOF-1 is not only the highest in the vinylene-linked COFs but also outstanding among the most reported COFs. This is the first application of zwitterionic COFs for photocatalytic hydrogen evolution, which would open a new frontier in zwitterionic COFs and be helpful for the design of other photocatalytic materials.

11.
ACS Appl Mater Interfaces ; 15(30): 36738-36747, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37487247

RESUMO

Shaping covalent organic frameworks (COFs) into macroscopic objects for practical application remains a huge challenge. Herein, a new thiadiazole-derived COF macroscopic ultralight aerogel (NNS-VCOF) was prepared through acid-catalyzed aldol condensation between 2,5-dimethyl-1,3,4-thiadiazole and a tritopic aromatic aldehyde derivative. NNS-VCOF aerogel shows extremely low density (ca. 0.020 g cm-3), excellent mechanical properties (compression modulus of 16.65 kPa), thermal insulation properties (low thermal conductivity of 0.03270 W m-1 K-1 at 25 °C), and flame retardancy (quickly self-extinguishing after ignition) due to its three-dimensional sponge-like architecture and special nitrogen heterocyclic framework. To our delight, NNS-VCOF aerogel not only can be used as an outstanding macroscopic material but also shows efficient photocatalytic hydrogen evolution properties in a powder state because of the superhydrophilicity and appropriate optical properties.

12.
Adv Fiber Mater ; : 1-43, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37361105

RESUMO

Hemodialysis, the most common modality of renal replacement therapy, is critically required to remove uremic toxins from the blood of patients with end-stage kidney disease. However, the chronic inflammation, oxidative stress as well as thrombosis induced by the long-term contact of hemoincompatible hollow-fiber membranes (HFMs) contribute to the increase in cardiovascular diseases and mortality in this patient population. This review first retrospectively analyzes the current clinical and laboratory research progress in improving the hemocompatibility of HFMs. Details on different HFMs currently in clinical use and their design are described. Subsequently, we elaborate on the adverse interactions between blood and HFMs, involving protein adsorption, platelet adhesion and activation, and the activation of immune and coagulation systems, and the focus is on how to improve the hemocompatibility of HFMs in these aspects. Finally, challenges and future perspectives for improving the hemocompatibility of HFMs are also discussed to promote the development and clinical application of new hemocompatible HFMs.

13.
Cell Biosci ; 13(1): 79, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147705

RESUMO

BACKGROUND: Where the gene is expressed determines the function of the gene. Neuregulin 1 (Nrg1) encodes a tropic factor and is genetically linked with several neuropsychiatry diseases such as schizophrenia, bipolar disorder and depression. Nrg1 has broad functions ranging from regulating neurodevelopment to neurotransmission in the nervous system. However, the expression pattern of Nrg1 at the cellular and circuit levels in rodent brain is not full addressed. METHODS: Here we used CRISPR/Cas9 techniques to generate a knockin mouse line (Nrg1Cre/+) that expresses a P2A-Cre cassette right before the stop codon of Nrg1 gene. Since Cre recombinase and Nrg1 are expressed in the same types of cells in Nrg1Cre/+ mice, the Nrg1 expression pattern can be revealed through the Cre-reporting mice or adeno-associated virus (AAV) that express fluorescent proteins in a Cre-dependent way. Using unbiased stereology and fluorescence imaging, the cellular expression pattern of Nrg1 and axon projections of Nrg1-positive neurons were investigated. RESULTS: In the olfactory bulb (OB), Nrg1 is expressed in GABAergic interneurons including periglomerular (PG) and granule cells. In the cerebral cortex, Nrg1 is mainly expressed in the pyramidal neurons of superficial layers that mediate intercortical communications. In the striatum, Nrg1 is highly expressed in the Drd1-positive medium spiny neurons (MSNs) in the shell of nucleus accumbens (NAc) that project to substantia nigra pars reticulata (SNr). In the hippocampus, Nrg1 is mainly expressed in granule neurons in the dentate gyrus and pyramidal neurons in the subiculum. The Nrg1-expressing neurons in the subiculum project to retrosplenial granular cortex (RSG) and mammillary nucleus (MM). Nrg1 is highly expressed in the median eminence (ME) of hypothalamus and Purkinje cells in the cerebellum. CONCLUSIONS: Nrg1 is broadly expressed in mouse brain, mainly in neurons, but has unique expression patterns in different brain regions.

14.
Nanomicro Lett ; 15(1): 109, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37071340

RESUMO

Realizing real-time monitoring of physiological signals is vital for preventing and treating chronic diseases in elderly individuals. However, wearable sensors with low power consumption and high sensitivity to both weak physiological signals and large mechanical stimuli remain challenges. Here, a flexible triboelectric patch (FTEP) based on porous-reinforcement microstructures for remote health monitoring has been reported. The porous-reinforcement microstructure is constructed by the self-assembly of silicone rubber adhering to the porous framework of the PU sponge. The mechanical properties of the FTEP can be regulated by the concentrations of silicone rubber dilution. For pressure sensing, its sensitivity can be effectively improved fivefold compared to the device with a solid dielectric layer, reaching 5.93 kPa-1 under a pressure range of 0-5 kPa. In addition, the FTEP has a wide detection range up to 50 kPa with a sensitivity of 0.21 kPa-1. The porous microstructure makes the FTEP ultra-sensitive to external pressure, and the reinforcements endow the device with a greater deformation limit in a wide detection range. Finally, a novel concept of the wearable Internet of Healthcare (IoH) system for real-time physiological signal monitoring has been proposed, which could provide real-time physiological information for ambulatory personalized healthcare monitoring.

15.
Sensors (Basel) ; 23(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36991758

RESUMO

The acquirement of the flow information in plate-fin heat exchanger (PFHE) is limited by its metal structure and complex flow condition. This work develops a new distributed optical measurement system to obtain flow information and boiling intensity. The system utilizes numerous optical fibers installed at the surface of the PFHE to detect optical signals. The attenuation and fluctuation of the signals reflect the variation of the gas-liquid interfaces and can be further used to estimate the boiling intensity. Practical experiments of flow boiling in PFHE with different heating fluxes have been carried out. The results verify that the measurement system can obtain the flow condition. Meanwhile, according to the results, the boiling development in PFHE can be divided into four stages with the increase in the heating flux, including the unboiling stage, initiation stage, boiling developing stage, and fully developed stage.

16.
RSC Adv ; 13(7): 4775-4780, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36760291

RESUMO

The relationship of the chiroptical response of a molecule to its absolution configuration does not exist now. In this letter, I intend to report a general rule with exceptions to predict the sign of optical rotation of chiral molecules with a RCHXY structure from their absolute configurations using the Hammett constant, σ p, which is based on the electron withdrawing/donating power of functional groups. In this rule, a priority list of functional groups based on the electron withdrawing powers of the groups are used. When the lowest priority group is in the back of the molecule, a clockwise arrangement of the other three priorities from the most electron withdrawing to the least withdrawing (1-2-3) is predicted to be dextrorotatory, the counterclockwise arrangement is predicted to be levorotatory.

17.
Entropy (Basel) ; 25(1)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36673289

RESUMO

Regularization with priors is an effective approach to solve the ill-posed inverse problem of electrical tomography. Entropy priors have been proven to be promising in radiation tomography but have received less attention in the literature of electrical tomography. This work aims to investigate the image reconstruction of capacitively coupled electrical resistance tomography (CCERT) with entropy priors. Four types of entropy priors are introduced, including the image entropy, the projection entropy, the image-projection joint entropy, and the cross-entropy between the measurement projection and the forward projection. Correspondingly, objective functions with the four entropy priors are developed, where the first three are implemented under the maximum entropy strategy and the last one is implemented under the minimum cross-entropy strategy. Linear back-projection is adopted to obtain the initial image. The steepest descent method is utilized to optimize the objective function and obtain the final image. Experimental results show that the four entropy priors are effective in regularization of the ill-posed inverse problem of CCERT to obtain a reasonable solution. Compared with the initial image obtained by linear back projection, all the four entropy priors make sense in improving the image quality. Results also indicate that cross-entropy has the best performance among the four entropy priors in the image reconstruction of CCERT.

18.
ACS Appl Bio Mater ; 6(1): 238-245, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36595712

RESUMO

Since the onset of the SARS-CoV-2 pandemic, the world has witnessed over 617 million confirmed cases and more than 6.54 million confirmed deaths, but the actual totals are likely much higher. The virus has mutated at a significantly faster rate than initially projected, and positive cases continue to surge with the emergence of ever more transmissible variants. According to the CDC, and at the time of this manuscript submission, more than 77% of all current US cases are a result of the B.5 (omicron). The continued emergence of highly transmissible variants makes clear the need for more effective methods of mitigating disease spread. Herein, we have developed an antimicrobial fabric capable of destroying a myriad of microbes including betacoronaviruses. We have demonstrated the capability of this highly porous and nontoxic metal organic framework (MOF), γ-CD-MOF-1, to serve as a host for varied-length benzalkonium chlorides (BACs; active ingredient in Lysol). Molecular docking simulations predicted a binding affinity of up to -4.12 kcal·mol-1, which is comparable to that of other reported guest molecules for this MOF. Similar Raman spectra and powder X-ray diffraction patterns between the unloaded and loaded MOFs, accompanied by a decrease in the Brunauer-Emmett-Teller surface area from 616.20 and 155.55 m2 g-1 respectively, corroborate the suggested potential for pore occupation with BAC. The MOF was grown on polypropylene fabric, exposed to a BAC-loading bath, washed to remove excess BAC from the external surface, and evaluated for its microbicidal activity against various bacterial and viral classes. Significant antimicrobial character was observed against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, bacteriophage, and betacoronavirus. This study shows that a common mask material (polypropylene) can be coated with BAC-loaded γ-CD-MOF-1 while maintaining the guest molecule's antimicrobial effects.


Assuntos
Anti-Infecciosos , COVID-19 , Estruturas Metalorgânicas , Humanos , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/química , Simulação de Acoplamento Molecular , Tensoativos , Polipropilenos , SARS-CoV-2
19.
Chemistry ; 29(1): e202202787, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36196504

RESUMO

The development of new vinylene-linked covalent organic frameworks (COFs) with special ionic structure and high stability is challenging. Herein, we report a facile, general method for constructing ionic vinylene-linked thiopyrylium-based COFs from 2,4,6-trimethylpyrylium tetrafluoroborate and other common reagents by means of acid-catalyzed Aldol condensation. Besides, pyrylium-, and pyridinium-based COFs also can be prepared from the same monomer under slightly different reaction conditions. The COFs exhibited uniform nanofibrous morphologies with excellent crystallinities, special ionic structures, well-defined nanochannels, and high specific surface areas.

20.
J Colloid Interface Sci ; 633: 1-10, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36427424

RESUMO

Problems such as cathode collapse caused by volume change and shuttle effect of lithium polysulfides (LiPSs) limit the commercialization of Lithium-Sulfur (Li-S). Herein, we developed a sulfhydryl-containing multifunctional binder prepared by the nucleophilic ring-opening reaction of thiocyclic carbonates with amino groups. The binders (CNP-T and CNP-F) form sulfur-containing polymers with sulfur through the wet-slurry process, thereby effectively suppressing the shuttle effect. The abundant polar functional groups (e.g., -NH2, -CS(NH)-) in CNP-T and CNP-F can effectively adsorb LiPSs to weaken the shuttle effect, which is confirmed by both density functional theory (DFT) and experimental results. At the same time, their own hyperbranched network structure can also limit the volume change of the sulfur cathode. Therefore, the Li-S battery exhibits an initial specific capacity of 924.02 mAh/g and a decay rate of 0.033% when cycled at 1C for 500 cycles.

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