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1.
Small ; 20(15): e2306237, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009589

RESUMO

Manganese-based materials are regarded as the most prospective cathode materials because of their high natural abundance, low toxicity, and high specific capacity. Nevertheless, the low conductivity, poor cycling performance, and controversial energy storage mechanisms hinder their practical application. Here, the MnS0.5Se0.5 microspheres are synthesized by a two-step hydrothermal approach and employed as cathode materials for aqueous zinc-ion batteries (AZIBs) for the first time. Interestingly, in-depth ex situ tests and electrochemical kinetic analyses reveal that MnS0.5Se0.5 is first irreversibly converted into low-crystallinity ZnMnO3 and MnOx by in situ electrooxidation (MnS0.5Se0.5-EOP) during the first charging process, and then a reversible co-insertion/extraction of H+/Zn2+ occurs in the as-obtained MnS0.5Se0.5-EOP electrode during the subsequent discharging and charging processes. Benefiting from the increased surface area, shortened ion transport path, and stable lamellar microsphere structure, the MnS0.5Se0.5-EOP electrodes deliver high reversible capacity (272.8 mAh g-1 at 0.1 A g-1), excellent rate capability (91.8 mAh g-1 at 2 A g-1), and satisfactory cyclic stability (82.1% capacity retention after 500 cycles at 1 A g-1). This study not only provides a powerful impetus for developing new types of manganese-based chalcogenides, but also puts forward a novel perspective for exploring the intrinsic mechanisms of in situ electrooxidation behavior.

2.
Clin Exp Rheumatol ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008294

RESUMO

OBJECTIVES: Behçet's disease (BD) is a chronic inflammatory condition with recurrent skin lesions, uveitis, and oral and genital ulcers. Neutrophils are important in the pathogenis of BD, but their molecular mechanisms are unclear. METHODS: We performed weighted gene co-expression network analysis on the transcriptome of neutrophils from 10 BD patients and 10 healthy controls to identify hub genes and gene modules associated with BD. RESULTS: We found eight co-expression modules with different biological functions. The turquoise module was involved in response to hydrogen peroxide and reactive oxygen species, the blue module was involved in response to external stimulus and inflammatory response, and the brown module was involved in the type I interferon signaling pathway. We further identified hub genes and transcription factors in each module by using module membership and gene significance. CONCLUSIONS: Our results reveal novel gene modules and hub genes that are associated with neutrophil activation and dysfunction in BD, which could serve as potential biomarkers and therapeutic targets for this disease.

3.
Org Biomol Chem ; 22(19): 3986-3994, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695061

RESUMO

Algae-based marine carbohydrate drugs are typically decorated with negative ion groups such as carboxylate and sulfate groups. However, the precise synthesis of highly sulfated alginates is challenging, thus impeding their structure-activity relationship studies. Herein we achieve a microwave-assisted synthesis of a range of highly sulfated mannuronate glycans with up to 17 sulfation sites by overcoming the incomplete sulfation due to the electrostatic repulsion of crowded polyanionic groups. Although the partially sulfated tetrasaccharide had the highest affinity for the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, the fully sulfated octasaccharide showed the most potent interference with the binding of the RBD to angiotensin-converting enzyme 2 (ACE2) and Vero E6 cells, indicating that the sulfated oligosaccharides might inhibit the RBD binding to ACE2 in a length-dependent manner.


Assuntos
Enzima de Conversão de Angiotensina 2 , Antivirais , Micro-Ondas , Polissacarídeos , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Chlorocebus aethiops , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/química , Células Vero , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/síntese química , Humanos , Animais , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Ácidos Hexurônicos/síntese química , Sulfatos/química , Sulfatos/farmacologia , Sulfatos/síntese química , Tratamento Farmacológico da COVID-19 , Relação Estrutura-Atividade
4.
BMC Public Health ; 24(1): 460, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355487

RESUMO

BACKGROUND: The COVID-19 pandemic has imposed unprecedented stress and challenges upon medical staff, potentially resulting in posttraumatic growth (PTG). This scoping review aims to synthesize the existing knowledge on PTG among medical staff during the pandemic by identifying its current status and potential influencing factors. The findings may provide a foundation for future research and interventions to enhance the medical staff's psychological resilience and well-being. METHODS: Literature was systematically searched on PTG among medical staff during the COVID-19 pandemic from 01 January 2020 to 31 December 2022. The following databases were searched: PubMed, Web of Science, Embase, CINAHL, PsycINFO, Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Service System (SinoMed), and Wanfang Data. Eligibility criteria included: (1) medical staff as research subjects; (2) a focus on "posttraumatic growth" or "alternative posttraumatic growth" related to the COVID-19 outbreak and pandemic; (3) discussion of the situation and influencing factors of PTG; and (4) study types, such as qualitative, quantitative, and mixed methods. Two researchers independently selected and extracted study characteristics (study design, study population, region, measurement instruments, and primary outcomes) from the included literature. The data were synthesized qualitatively and descriptively. RESULTS: Thirty-six papers from 12 countries met the inclusion criteria. Moderate PTG levels were observed among healthcare workers during the COVID-19 pandemic, with emphasis on "interpersonal relationships," "changes in life philosophy," and "growth in personal competence." Influencing factors included trauma exposure, sociodemographics, psychological characteristics (resilience and positive qualities), coping, and social support. CONCLUSIONS: This review discovered moderate PTG levels among medical staff during the COVID-19 pandemic, with critical areas in interpersonal relationships, life philosophy, and personal competence. The identified influencing factors can inform future research and interventions to enhance healthcare workers' psychological resilience and well-being.


Assuntos
COVID-19 , Crescimento Psicológico Pós-Traumático , Resiliência Psicológica , Humanos , Pandemias , Corpo Clínico
5.
Clin Oral Investig ; 28(6): 352, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822874

RESUMO

BACKGROUND: The relationship between tooth colour and individual satisfaction in oral aesthetics has long been a topic of interest. In this study, we utilized the fuzzy analytic hierarchy process (FAHP) to investigate the impacts of sex and age on tooth colour preference. The findings of this study should provide a scientific basis for oral aesthetic practice. METHODS: In the current study, a random selection method was employed, and a survey was completed by 120 patients. To obtain tooth colour data, standard tooth colour charts were used. Smile photos were taken as template images using a single-lens reflex camera. The FAHP was utilized to conduct a weight analysis of tooth colour preferences among patients of different sexes and age groups. RESULTS: There were significant differences in tooth colour preference based on sex and age. Men tend to prefer the B1 colour, while women may prioritize the aesthetic effects of other colours. Additionally, as patients age, their preferences for tooth colour become more diverse. These findings offer valuable insights for oral aesthetics practitioners, enabling them to better address the aesthetic needs of patients across different sexes and ages. This knowledge can aid in the development of more personalized treatment plans that align with patients' expectations. CONCLUSION: In this study, we utilized scientific analysis methods to quantify the popularity of different tooth colours among various groups of people. By doing so, we established a scientific foundation for clinical practice. The findings of this study offer valuable insights for oral aesthetic research, enhancing our understanding of tooth colour. Additionally, these findings have practical applications in the field of oral medicine, potentially improving patients' quality of life and overall oral health.


Assuntos
Estética Dentária , Humanos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Fatores Sexuais , Fatores Etários , Cor , Inquéritos e Questionários , Sorriso , Idoso , Adolescente , Fotografia Dentária , Dente , Preferência do Paciente
6.
BMC Oral Health ; 24(1): 488, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658882

RESUMO

BACKGROUND: Orthodontics is a common treatment for malocclusion and is essential for improving the oral health and aesthetics of patients. Currently, patients often rely on the clinical expertise and professional knowledge of doctors to select orthodontic programs. However, they lack their own objective and systematic evaluation methods to quantitatively compare different programs. Therefore, there is a need for a more comprehensive and quantitative approach to selecting orthodontic treatment plans, aiming to enhance their scientific validity and effectiveness. METHODS: In this study, a combination of the analytic hierarchy process (AHP) and semantic analysis was used to evaluate and compare different orthodontic treatment options. An AHP model and evaluation matrix were established through thorough research and semantic analysis of patient requirements. This model considered various treatment factors. Expert panels were invited to rate these factors using a 1-9 scale. The optimal solution was determined by ranking and comparing different orthodontic treatment plans using the geometric mean method to calculate the weights of each criterion. RESULTS: The research indicates a higher preference for invisible correction compared to other orthodontic solutions, with a weight score that is 0.3923 higher. Factors such as comfort and difficulty of cleaning have been given significant attention. CONCLUSION: The Analytic Hierarchy Process (AHP) method can be utilized to effectively develop orthodontic treatment plans, making the treatment process more objective, scientific, and personalized. The design of this study offers strong decision support for orthodontic treatment, potentially improving orthodontic treatment outcomes in clinical practice and ultimately enhancing oral health and patients' quality of life.


Assuntos
Má Oclusão , Ortodontia Corretiva , Humanos , Ortodontia Corretiva/métodos , Má Oclusão/terapia , Planejamento de Assistência ao Paciente , Tomada de Decisões , Tomada de Decisão Clínica , Técnicas de Apoio para a Decisão
7.
Small ; 19(15): e2207975, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36631278

RESUMO

Transition metal selenides anodes with fast reaction kinetics and high theoretical specific capacity are expected to solve mismatched kinetics between cathode and anode in Li-ion capacitors. However, transition metal selenides face great challenges in the dissolution and shuttle problem of lithium selenides, which is the same as Li-Se batteries. Herein, inspired by the density functional theory calculations, heterogeneous can enhance the adsorption of Li2 Se relative to single component selenide electrodes, thus inhibiting the dissolution and shuttle effect of Li2 Se. A heterostructure material (denoted as CoSe2 /SnSe) with the ability to evolve continuously (CoSe2 /SnSe→Co/Sn→Co/Li13 Sn5 ) is successfully designed by employing CoSnO3 -MOF as a precursor. Impressively, CoSe2 /SnSe heterostructure material delivers the ultrahigh reversible specific capacity of 510 mAh g-1 after 1000 cycles at the high current density of 4 A g-1 . In situ XRD reveals the continuous evolution of the interface based on the transformation and alloying reactions during the charging and discharging process. Visualizations of in situ disassembly experiments demonstrate that the continuously evolving interface inhibits the shuttle of Li2 Se. This research proposes an innovative approach to inhibit the dissolution and shuttling of discharge intermediates (Li2 Se) of metal selenides, which is expected to be applied to metal sulfides or Li-Se and Li-S energy storage systems.

8.
Molecules ; 28(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36985464

RESUMO

In this work, CuS, Cu7S4, Cu9S5, Cu7.2S4, and Cu2S with the same morphology were successfully synthesized by the hydrothermal method. According to the calculation, their galvanostatic charge-discharge (GCD) curves were 43.29 (CuS), 86.3 (Cu7S4), 154 (Cu9S5), 185.4 (Cu7.2S4), and 206.9 F/g (Cu2S) at the current density of 1 A/g. The results showed that the energy storage capacity of copper sulfide with the same morphology increased with the increase of the copper sulfide stoichiometric coefficient. At the second part of this work, the agglomerated cuprous sulfide and the microporous cuprous sulfide were successfully prepared, respectively. In addition, the porous spherical cuprous sulfide was annealed to get nano cuprous sulfide. It is found that the specific capacity of the agglomerated structure is the highest, which had reached 206.9 F/g at the current density of 1 A/g, and 547.9 F/g at the current density of 10 A/g after activation.

9.
Breast Cancer Res ; 17(1): 138, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26526858

RESUMO

INTRODUCTION: Increased animal fat consumption is associated with increased premenopausal breast cancer risk in normal weight, but not overweight, women. This agrees with our previous findings in obesity-resistant BALB/c mice, in which exposure to a high saturated animal fat diet (HFD) from peripuberty through adulthood promoted mammary tumorigenesis. Epidemiologic and animal studies support the importance of puberty as a life stage when diet and environmental exposures affect adult breast cancer risk. In this study, we identified the effects of peripubertal exposure to HFD and investigated its mechanism of enhancing tumorigenesis. METHODS: Three-week-old BALB/c mice fed a low-fat diet (LFD) or HFD were subjected to 7,12-dimethylbenz[a]anthracene (DMBA)-induced carcinogenesis. At 9 weeks of age, half the mice on LFD were switched to HFD (LFD-HFD group) and half the mice on HFD were switched to LFD (HFD-LFD group). Tumor gene expression was evaluated in association with diet and tumor latency. RESULTS: The peripubertal HFD reduced the latency of DMBA-induced mammary tumors and was associated with tumor characteristics similar to those in mice fed a continuous HFD. Notably, short-latency tumors in both groups shared gene expression characteristics and were more likely to have adenosquamous histology. Both HFD-LFD and continuous HFD tumors showed similar gene expression patterns and early latency. Adult switch from HFD to LFD did not reverse peripubertal HFD tumor promotion. Increased proliferation, hyperplasia, and macrophages were present in mammary glands before tumor development, implicating these as possible effectors of tumor promotion. Despite a significant interaction between pubertal diet and carcinogens in tumor promotion, peripubertal HFD by itself produced persistent macrophage recruitment to mammary glands. CONCLUSIONS: In obesity-resistant mice, peripubertal HFD is sufficient to irreversibly promote carcinogen-induced tumorigenesis. Increased macrophage recruitment is likely a contributing factor. These results underscore the importance of early life exposures to increased adult cancer risk and are consistent with findings that an HFD in normal weight premenopausal women leads to increased breast cancer risk. Notably, short-latency tumors occurring after peripubertal HFD had characteristics similar to human basal-like breast cancers that predominantly develop in younger women.


Assuntos
Carcinogênese/metabolismo , Carcinoma Adenoescamoso/etiologia , Dieta Hiperlipídica/efeitos adversos , Neoplasias Mamárias Experimentais/etiologia , Animais , Carcinoma Adenoescamoso/metabolismo , Quimiocinas/metabolismo , Feminino , Glândulas Mamárias Animais/crescimento & desenvolvimento , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/metabolismo , Camundongos Endogâmicos BALB C , Maturidade Sexual , Transcriptoma , beta Catenina/metabolismo
10.
Phys Chem Chem Phys ; 17(24): 15764-70, 2015 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-26016643

RESUMO

Rutile TiO2 microspheres anchored by nanoneedle clusters, as a new class of anode materials, are successfully employed for sodium-ion batteries and manifested good energy storage behavior. The initial discharge capacity of 308.8 mA h g(-1) is obtained and a high reversible capacity of 121.8 mA h g(-1) is maintained after 200 cycles at a current density of 0.1 C, exhibiting a high capacity retention of 83.1%. All these merits are not only ascribed to the rutile TiO2 crystal structure, but also thanks to the porous morphology of hundreds of nanoneedle clusters in favor of sodium diffusion and accommodating the strain during the sodiation and desodiation processes. Therefore, it is highly expected that rutile TiO2, as a feasible electrochemical sodium storage material, can be a new promising candidate as an anode for sodium-ion batteries.

11.
Phys Chem Chem Phys ; 17(1): 159-65, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25372713

RESUMO

The ion-migration mechanism of Na3V2(PO4)2F3 is investigated in Na3V2(PO4)2F3-Li hybrid-ion batteries for the first time through a combined computational and experimental study. There are two Na sites namely Na(1) and Na(2) in Na3V2(PO4)2F3, and the Na ions at Na(2) sites with 0.5 occupation likely extract earlier to form Na2V2(PO4)2F3. The structural reorganisation is suggested to make a stable configuration of the remaining ions at the centre of Na(1) sites. After the extraction of the second Na ion, the last ion prefers to change occupation from 1 to 0.5 to occupy two Na(2) sites. The insertion of predominant Li ions also should undergo structural reorganization when the first Li ion inserts into the centre of Na(1) site theoretically forming NaLiV2(PO4)2F3, and the second ion inserts into two Na(2) sites to form NaLi2V2(PO4)2F3. More than a 0.3 Li ion insertion would take place in the applied voltage range by increasing the number of sites occupied rather than occupy the vacancy in triangular prismatic sites. An improved solution-based carbothermal reduction methodology makes Na3V2(PO4)2F3 exhibit excellent C-rate and cycling performances, of which the Li-inserted voltage is evaluated by first principles calculations.

12.
Langmuir ; 30(41): 12438-46, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25212063

RESUMO

The electrochemical properties of Na3V2(PO4)2F3 cathode utilized in the sodium ion battery are investigated, and the ion migration mechanisms are proposed as combined via the first principles calculations. Two different Na sites, namely, the Na(1) and Na(2) sites, could cause two sodium ions of Na3V2(PO4)2F3 to be extracted or inserted by a two-step electrochemical process accompanied by structural reorganization that could be responsible for the redox reaction of V(3+/4+). Because the calculated average voltage (V(avg)) of the second charging plateau is 4.04 V for the optimized system but 4.38 V for the unoptimized one, the reorganization of the cathode system can make a stable configuration and lower the extraction energy. Three designed pathways for sodium ions along the x, y, z directions in Na3V2(PO4)2F3, known as a 3D ions transport tunnel, have activation energies (Ea) of 0.449, 0.2, and 0.323 eV, respectively, by using DFT calculations, demonstrating the different feasibilities of the migration directions.

13.
Clin Exp Neuroimmunol ; 15(1): 55-60, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595690

RESUMO

We report a rare case of paraneoplastic neurological syndrome with dual seropositivity of anti-aquaporin-4 and myelin oligodendrocyte glycoprotein antibodies in a 40 year-old woman with metastatic triple-negative breast cancer. She received multiple lines of anti-neoplastic treatment, including immunotherapy with pembrolizumab, as well as cytotoxic chemotherapy. Paraneoplastic meningoencephalomyelitis developed 2 years after diagnosis of breast cancer and 1 year after discontinuation of immunotherapy with pembrolizumab. She first developed longitudinally extending transverse myelitis followed by left optic neuritis and meningoencephalitis with new enhancing lesions in the brain and spinal leptomeninges. Cerebrospinal fluid analysis during both episodes showed normal glucose and protein, and elevated white blood cell count. Cytology was negative for malignancy. Cerebrospinal fluid was positive for neuromyelitis optica immunoglobulin G antibody anti-aquaporin-4, and autoimmune myelopathy panel was positive for myelin oligodendrocyte glycoprotein antibody. The patient had significant clinical and radiographic improvement after completion of five cycles of plasmapheresis followed by intravenous immunoglobulin. She did not have recurrence of paraneoplastic syndrome with maintenance rituximab every 6 months and daily low-dose prednisone. She succumbed to progressive systemic metastatic disease 4.5 years after her breast cancer diagnosis. This case shows that these antibodies can occur concurrently and cause clinical features, such as both neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody disease, in a patient with a singular type of cancer. We highlight the importance of testing for paraneoplastic etiology in cancer patients with radiographic menigoencephalomyelitis or meningitis with atypical symptoms of meningeal carcinomatosis and/or cerebrospinal fluid profile negative for leptomeningeal carcinomatosis.

14.
Curr Med Sci ; 44(2): 328-332, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38517677

RESUMO

OBJECTIVE: This study aimed to investigate the incidence of enteral nutrition intolerance (ENI) in patients with sepsis and explore potential risk factors. METHODS: A case-control study was conducted in patients with sepsis who were receiving enteral nutrition (EN) at a tertiary hospital in China. The included patients were divided into the ENI group and the non-ENI group. Univariate and multivariate analyses were performed to identify the risk factors for ENI. RESULTS: A total of 859 patients were included in the study. Among them, 288 (33.53%) patients experienced symptoms of ENI, including diarrhea, vomiting, bloating, and gastric retention. Logistic regression analysis revealed that the Acute Physiology and Chronic Health Evaluation H (APACHE H) score, thoracocentesis, and usage of cardiotonic drugs (namely, inotropes) were independent predictors of the ENI. CONCLUSION: The incidence of ENI is relatively high in patients with sepsis, especially in those who have higher APACHE H scores, have undergone thoracocentesis, and have received inotropes.


Assuntos
Nutrição Enteral , Sepse , Humanos , Estudos de Casos e Controles , Estado Nutricional , Sepse/complicações , Sepse/epidemiologia , Fatores de Risco
15.
Phys Chem Chem Phys ; 15(34): 14357-63, 2013 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-23877439

RESUMO

A NASICON-structure Na3V2(PO4)3 cathode material prepared by carbothermal reduction method is employed in a hybrid-ion battery with Li-involved electrolyte and anode. The ion-transportation mechanism is firstly investigated in this complicated system for an open three-dimensional framework Na3V2(PO4)3. Ion-exchange is greatly influenced by the standing time, for example, the 1 hour battery presents a specific capacity of 128 mA h g(-1) while the 24 hour battery exhibits a value of 148 mA h g(-1) with improved rate and cycling performances over existing literature reported Li-ion batteries. In the hybrid-ion system, an ion-exchange process likely takes place between the two Na(2) sites in the rhombohedral structure. NaLi2V2(PO4)3 could be produced by ion-transportation since the Na(+) in the Na(1) site is stationary and the three Na(2) sites could be used to accommodate the incoming alkali ions; Li(x)Na(y)V2(PO4)3 would come out when the vacant site in Na(2) was occupied depending on the applied voltage range. The reported methodology and power characteristics are greater than those previously reported.

16.
J Colloid Interface Sci ; 641: 831-841, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36966572

RESUMO

Mo-based heterostructures offer a new strategy to improve the electronics/ion transport and diffusion kinetics of the anode materials for sodium-ion batteries (SIBs). MoO2/MoS2 hollow nanospheres have been successfully designed via in-situ ion exchange technology with the spherical coordination compound Mo-glycerates (MoG). The structural evolution processes of pure MoO2, MoO2/MoS2, and pure MoS2 materials have been investigated, illustrating that the structureofthenanospherecan be maintained by introducing the S-Mo-S bond. Based on the high conductivity of MoO2, the layered structure of MoS2 and the synergistic effect between components, as-obtained MoO2/MoS2 hollow nanospheres display enhanced electrochemical kinetic behaviors for SIBs. The MoO2/MoS2 hollow nanospheres achieve a rate performance with 72% capacity retention at a current of 3200 mA g-1 compared to 100 mA g-1. The capacity can be restored to the initial capacity after a current returns to 100 mA g-1, while the capacity fading of pure MoS2 is up to 24%. Moreover, the MoO2/MoS2 hollow nanospheres also exhibit cycling stability, maintaining a stable capacity of 455.4 mAh g-1 after 100 cycles at a current of 100 mA g-1. In this work, the design strategy for the hollow composite structure provides insight into the preparation of energy storage materials.

17.
J Colloid Interface Sci ; 611: 183-192, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34952272

RESUMO

With the fast development of flexible wearable electronics, mobile electronic equipment, electric tool and electric vehicles, high specific capacity, superior cycle stability and excellent fast-charge performance are required for lithium-ion batteries (LIBs). Nevertheless, commercial graphite with the limited theoretical capacity (372 mAh g-1) and short lifespan is difficult to satisfy the requirements of the new generation of LIBs. In this work, the three-dimensional flexible molybdenum oxynitride (MNO) thin films with non-binder were prepared by magnetron sputtering approach. The charge transfer resistance and Li-ion diffusion coefficient were measured by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV), and the results show that molybdenum nitride is helpful to increase the diffusion and electron transfer of Li-ion. The MNO thin film annealed at 300 °C with irregular aggregate matrix structure shows a discharge capacity of 413 mAh g-1 after 180 cycles at 1 A g-1. The outstanding rate performance and cycle stability suggest that these binder-free thin film electrodes, especially nitrides, offer great opportunity for energy storage systems with fast-charge capabilities.

18.
Org Lett ; 24(45): 8381-8386, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36346693

RESUMO

Pseudomonas aeruginosa is a leading cause of urinary tract, pulmonary, and wound infections and is becoming increasingly resistant to antibiotics. Here, we report the iodonium- and gold(I)-promoted bimodal glycosylation of glycosyl (Z)-ynenoates for highly ß-selective promoter-controlled synthesis and antigenic evaluation of a series of 1,2-cis-ß-linked mannuronic acid alginate glycans of P. aeruginosa up to a 24-mer, which represents the longest polymannuronic acid synthesized to date. By screening the six synthetic mannuronic acid alginate glycans with the mouse serum antibodies, we identified the mannuronic acid tetrasaccharide as the optimal antigen epitope for the development of vaccines against P. aeruginosa.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Camundongos , Animais , Infecções por Pseudomonas/prevenção & controle , Alginatos , Ácidos Hexurônicos
19.
Front Chem ; 8: 150, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32185164

RESUMO

In this study, two kinds of composites with the structure of graphene oxide (GO) sheets wrapped magnetic nanoparticles were investigated on their regeneration. The composites have a similar core-shell structure, but the interactions between the core and shell are quite different, which are electrostatic and covalent. They were characterized by scanning/transmission electron microscopy, power X-ray diffraction, and vibrating sample magnetometer analysis. Their morphologies and structures of the samples had been revealed using methylene blue and Pb(II) as adsorbates during regeneration. The results showed that the composites with covalent bonding interaction could maintain a stable core-shell structure and present a good regeneration performance for adsorption-desorption of methylene blue and Pb(II). The composites with electrostatic interaction could approximately preserve its core-shell structure and could be recyclable for adsorption-desorption of methylene blue, however, they would disintegrate its core-shell structure during adsorption/desorption of Pb(II), thus greatly decreasing their regeneration performance. The regeneration mechanisms of the composites were analyzed, which could provide a useful theoretical guide to design the GO sheets wrapped magnetic nanoparticles composites.

20.
Front Chem ; 8: 232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32296683

RESUMO

Polymer electrolytes for Li metal batteries (LMBs) should be modified to improve their ionic conductivity and stability against the lithium electrode. In this study, graphene oxide (GO) was modified by ion liquid (IL), and the IL modified GO (GO-IL) had been used as a filler for polyethylene oxide (PEO). The obtained solid polymer electrolyte (SPE) is of high ionic conductivity, low crystallinity and excellent stability against the lithium electrode. The PEO/GO-IL was characterized by various techniques, and its structure and performance were analyzed in detail. By addition of 1% GO-IL, the ionic conductivity of the PEO/GO-IL SPE reaches 1.8 × 10-5 S cm-1 at 25°C, which is 10 times higher than PEO (1.7 × 10-6 S cm-1), and the current density for stable Li plating/stripping in PEO/GO-IL can be increased to 100 µA cm-2 at 60°C. LiFePO4/Li cell (using PEO/GO-IL SPE) tests indicated that the initial discharge capacity can reach ~145 mA h g-1 and capacity retention can maintain 88% even after 100 cycles at a rate of 0.1C and at 60°C. Our creative work could provide a useful method to develop SPEs with excellent performance, thus accelerating the commercial application of LMBs.

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