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1.
Angew Chem Int Ed Engl ; : e202402625, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709979

RESUMEN

The interfacial instability of high-nickel layered oxides severely plagues practical application of high-energy quasi-solid-state lithium metal batteries (LMBs). Herein, a uniform and highly oxidation-resistant polymer layer within inner Helmholtz plane is engineered by in situ polymerizing 1-vinyl-3-ethylimidazolium (VEIM) cations preferentially adsorbed on LiNi0.83Co0.11Mn0.06O2 (NCM83) surface, inducing the formation of anion-derived cathode electrolyte interphase with fast interfacial kinetics. Meanwhile, the copolymerization of [VEIM][BF4] and vinyl ethylene carbonate (VEC) endows P(VEC-IL) copolymer with the positively-charged imidazolium moieties, providing positive electric fields to facilitate Li+ transport and desolvation process. Consequently, the Li||NCM83 cells with a cut-off voltage up to 4.5 V exhibit excellent reversible capacity of 130 mAh g-1 after 1000 cycles at 25 °C and considerable discharge capacity of 134 mAh g-1 without capacity decay after 100 cycles at -20 °C. This work provides deep understanding on tailoring electric double layer by cation specific adsorption for high-voltage quasi-solid-state LMBs.

2.
J Am Chem Soc ; 145(47): 25632-25642, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37943571

RESUMEN

Owing to high ionic conductivity and mechanical strength, poly(vinylidene fluoride) (PVDF) electrolytes have attracted increasing attention for solid-state lithium batteries, but highly reactive residual solvents severely plague cycling stability. Herein, we report a free-solvent-capturing strategy triggered by reinforced ion-dipole interactions between Li+ and residual solvent molecules. Lithium difluoro(oxalato)borate (LiDFOB) salt additive with electron-withdrawing capability serves as a redistributor of the Li+ electropositive state, which offers more binding sites for residual solvents. Benefiting from the modified coordination environment, the kinetically stable anion-derived interphases are preferentially formed, effectively mitigating the interfacial side reactions between the electrodes and electrolytes. As a result, the assembled solid-state battery shows a lifetime of over 2000 cycles with an average Coulombic efficiency of 99.9% and capacity retention of 80%. Our discovery sheds fresh light on the targeted regulation of the reactive residual solvent to extend the cycle life of solid-state batteries.

3.
J Am Chem Soc ; 145(3): 1728-1739, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36640116

RESUMEN

Single-atom catalysts have been paid more attention to improving sluggish reaction kinetics and anchoring polysulfide for lithium-sulfur (Li-S) batteries. It has been demonstrated that d-block single-atom elements in the fourth period can chemically interact with the local environment, leading to effective adsorption and catalytic activity toward lithium polysulfides. Enlightened by theoretical screening, for the first time, we design novel single-atom Nb catalysts toward improved sulfur immobilization and catalyzation. Calculations reveal that Nb-N4 active moiety possesses abundant unfilled antibonding orbitals, which promotes d-p hybridization and enhances anchoring capability toward lithium polysulfides via a "trapping-coupling-conversion" mechanism. The Nb-SAs@NC cell exhibits a high capacity retention of over 85% after 1000 cycles, a superior rate performance of 740 mA h g-1 at 7 C, and a competitive areal capacity of 5.2 mAh cm-2 (5.6 mg cm-2). Our work provides a new perspective to extend cathodes enabling high-energy-density Li-S batteries.

4.
Nano Lett ; 22(13): 5553-5560, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35708317

RESUMEN

With the development of flexible devices, it is necessary to design high-performance power supplies with superior flexibility, durability, safety, etc., to ensure that they can be deformed with the device while retaining their electrochemical functions. Herein, we have designed a flexible lithium-ion battery inspired by the DNA helix structure. The battery structure is mainly composed of multiple thick energy stacks for energy storage and some grooves for stress buffers, which realized the spiral deformation of batteries. According to the results, the batteries exhibit less than 3% capacity degradation even after more than 31000 times of in situ dynamic mechanical loadings. Moreover, the mechanism of the battery with spiral deformability is further revealed. It is anticipated that this bioinspired design strategy could create unique opportunities for the commercialization of flexible batteries and fill the current gap in realizing battery-specific deformations to meet various requirements for future complex device designs.


Asunto(s)
Suministros de Energía Eléctrica , Litio , ADN , Iones , Litio/química
5.
Small ; 18(45): e2204745, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36148862

RESUMEN

Emerging directions in the growing wearable electronics market have spurred the development of flexible energy storage systems that require deformability while maintaining electrochemical performance. However, the traditional fabrication approaches of lithium-ion batteries (LIBs) are challenging to withstand long-cycle bending alternating loads due to the stress concentration caused by the nonuniformity of the actual deformation. Herein, inspired by kirigami, a segmented deformation design of full-cell scale thin-type flexible lithium-ion batteries (FLIBs) with large-scale manufacturing characteristics via the current collector's mechanical blanking process is reported. This strategy allows the battery's elliptical deformation of the actual state to be transformed into the circular strain of the ideal configuration, thereby dispersing the stress concentration on the top of the battery. According to the results, the designed battery maintains >95% capacity after >20 000 harsh in situ dynamic tests. In addition, finite element analysis further reveals the mechanism that the segmented deformation strategy bears the mechanical stress. This work can enlighten the rational design and customization of electrode patterns for high compatibility with various devices, thereby providing potential opportunities for the application of FLIBs.

6.
Support Care Cancer ; 29(3): 1369-1375, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32661697

RESUMEN

PURPOSE: Increasing evidence suggests that many adipokines are involved in cancer-related anorexia and cachexia syndrome (CACS), although the underlying mechanism remains to be clarify. Asprosin is a new peptide hormone mainly secreted by white adipose tissues that can increase appetite and body weight. In this cross-sectional study, we tested whether asprosin may intervene in the development of CACS. METHODS: The fasting plasma asprosin levels were determined via enzyme-linked immune-sorbent assay. Anorexia was determined using the anorexia/cachexia subscale (A/CS) of the functional assessment of anorexia/cachexia therapy (FAACT) questionnaire. The body composition was assessed using bioelectrical impedance analysis. The association of plasma asprosin with anorexia, cachexia, and nutritional status was analyzed. RESULTS: One hundred twenty treatment-naïve patients with pathological confirmed gastrointestinal or lung cancer and 14 mild gastritis patients were recruited. We found no significant difference in asprosin levels between subgroups of patients by age, sex, cancer types or stage. Correlation analysis suggested that asprosin levels were positively associated with body fat mass (r = 0.248, p = 0.043). No correlations were found between asprosin levels and hemoglobin, white blood cell count, blood platelet count, albumin, C-reactive protein, glucose, cholesterol, triglyceride, high density lipoprotein, low density lipoprotein, body mass index, body fat percentage, protein, skeletal muscle, muscle mass, lean body mass, and basal metabolic rate. Furthermore, asprosin levels were not significantly different between patients with or without cachexia. However, patients with anorexia had significantly lower asprosin levels compared with patients without anorexia. No significant difference in asprosin levels between gastritis and gastric cancer patients. Similarly, no significant change of asprosin levels occurred postoperatively in 10 gastric cancer patients. CONCLUSIONS: Patients with anorexia had significantly lower asprosin levels compared with patients without anorexia. We therefore speculated that asprosin might intervene in the development of cancer anorexia and serve as a potential therapeutic target.


Asunto(s)
Anorexia/terapia , Composición Corporal/genética , Peso Corporal/genética , Caquexia/terapia , Fibrilina-1/uso terapéutico , Proteína C-Reactiva/metabolismo , Estudios Transversales , Femenino , Humanos , Masculino
7.
Appl Microbiol Biotechnol ; 104(19): 8155-8170, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32830294

RESUMEN

Since the first discovery of old yellow enzyme 1 (OYE1) from Saccharomyces pastorianus in 1932, biocatalytic asymmetric reduction of activated alkenes by OYEs has become a valuable reaction in organic synthesis. To access stereocomplementary C=C-bond bioreduction, the mining of novel OYEs and especially the protein engineering of existing OYEs have been performed, which successfully achieved the stereocomplementary reduction in several cases and further raise the potential of applications. In this review, we analyzed the structures, active sites, and substrate recognition of OYEs, which are the bases for their substrate specificity and stereospecificity. Sequence similarity network of OYEs superfamily was also constructed to investigate the scope of characterized OYEs. The structure-guided engineering to switch the stereoselectivity of OYEs and thus access stereocomplementary bioreduction over the last decade (2009-2020) was then reviewed and discussed, which might give new insights into the mining and engineering of related biocatalysts. KEY POINTS: • The sequence similarity network of OYEs superfamily was constructed and annotated. • The structures and active sites of OYEs from different classes were compared. • "Left/right" binding mode was used to explain the stereopreferences of OYEs. • Structure-guided engineering of OYEs to switch their stereoselectivity was reviewed.


Asunto(s)
NADPH Deshidrogenasa , Ingeniería de Proteínas , Biocatálisis , Dominio Catalítico , NADPH Deshidrogenasa/metabolismo , Saccharomyces , Estereoisomerismo , Especificidad por Sustrato
8.
J Geriatr Psychiatry Neurol ; 32(6): 327-335, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31480988

RESUMEN

PURPOSE: The aim of this study was to investigate the association between preexisting cerebral abnormalities in patients with acute ischemic stroke upon their functional outcomes. METHODS: We recruited 272 patients with first-ever acute ischemic stroke. Cerebral abnormalities on magnetic resonance imaging included infarction, silent brain infarcts (SBI), enlarged perivascular spaces, white matter lesions (WMLs), global brain atrophy, and medial temporal lobe atrophy (MTLA). Functional outcomes were assessed using the instrumental activities of daily living (IADL) scale and basic activities of daily living (BADL) scale, at 3 and 6 months after the index stroke. RESULTS: Two hundred and fifty patients completed the 3-month follow-up and 246 patients completed the 6-month follow-up. Univariate analyses showed that patients with poor IADL and BADL were older, more likely to be men, had higher National Institutes of Health Stroke Scale (NIHSS) score on admission, more frequent atrial fibrillation, and large artery atherosclerosis subtypes. They also had more frequent cortical infarcts, subcortical infarcts, infratentorial infarcts, larger infarct volume, more frequent presence of SBI, severe WMLs, and MTLA. In multiple regression analyses, NIHSS on admission, subcortical region infarct and MTLA were significant predictors of poor IADL at 3 months. National Institutes of Health Stroke Scale on admission, SBI and MTLA were significant predictors of poor IADL at 6 months. National Institutes of Health Stroke Scale on admission and MTLA were significant predictors of poor BADL at 3 months. National Institutes of Health Stroke Scale on admission and SBI were significant predictors of poor BADL at 6 months. CONCLUSIONS: In patients with acute ischemic stroke, the presence of SBI, and severe MTLA represent significant predictors of poorer functional outcomes, thus highlighting the importance of preexisting cerebral abnormalities.


Asunto(s)
Isquemia Encefálica/fisiopatología , Cerebro/patología , Imagen por Resonancia Magnética/métodos , Accidente Cerebrovascular/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
9.
Stroke ; 49(12): 2983-2989, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30571427

RESUMEN

Background and Purpose- The aim of the study was to assess the effect of lesion severity in cortical cholinergic pathways in acute ischemic stroke patients on functional outcomes. Methods- The study sample consisted of 214 men (70.9%) and 88 women (29.1%) with acute ischemic stroke. We used the Cholinergic Pathways Hyperintensities Scale (CHIPS) to assess the severity of lesions in cortical cholinergic pathways using brain magnetic resonance imaging. The other magnetic resonance imaging parameters included infarction, white matter lesions, and medial temporal lobe atrophy. Functional outcome was assessed using the Lawton activities of daily living (ADL) scale at 3 and 6 months after the index stroke. We also assessed disability status using the modified Rankin Scale. Results- Univariate analysis showed that patients with poor functional outcomes were older, more likely to be men, had a higher National Institutes of Health Stroke Scale (NIHSS) score on admission, and had more frequent histories of previous stroke and infection complications. They also had significantly more frequent cortical infarcts, left subcortical infarcts, a larger infarct volume, more severe medial temporal lobe atrophy, and periventricular hyperintensities, and higher CHIPS scores. In the multiple regression analysis, model 1 showed that age and NIHSS score on admission were significant predictors of poor ADL at 3 months, with an R2 of 45.4% fitting the model. Age, NIHSS score on admission and stroke subtype were also significant predictors of poor ADL at 6 months, with an R2 of 37.9% fitting the model. In model 2, sex, previous stroke, NIHSS score on admission, right cortical infarcts, left subcortical infarcts and CHIPS score were significant predictors for poor ADL at 3 months, with an R2 of 53.5%. NIHSS score on admission, stroke subtype, and CHIPS score were significant predictors for poor ADL at 6 months, with an R2 of 40.2%. After adjustment for confounders, CHIPS score was also a significant predictor for poor modified Rankin Scale, both at 3 and 6 months. Even after removing patients with moderate-to-severe white matter lesions, higher CHIPS scores still correlated with poorer ADL and modified Rankin Scale both at both 3 and 6 months. Conclusions- In patients with acute ischemic stroke, cortical cholinergic pathways impairment is common, and the severity of lesions in the cortical cholinergic pathways may significantly predict a poorer functional outcome. Clinical Trial Registration- URL: http://www.chictr.org.cn/index.aspx . Unique identifier: ChiCTR1800014982.


Asunto(s)
Actividades Cotidianas , Núcleo Basal de Meynert/diagnóstico por imagen , Isquemia Encefálica/fisiopatología , Corteza Cerebral/diagnóstico por imagen , Accidente Cerebrovascular/fisiopatología , Anciano , Isquemia Encefálica/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Pronóstico , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/diagnóstico por imagen , Lóbulo Temporal/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen
10.
PLoS One ; 19(3): e0295051, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38470901

RESUMEN

Currently, most diagnoses of depression are evaluated by medical professionals, with the results of these evaluations influenced by the subjective judgment of physicians. Physiological studies have shown that depressed patients display facial movements, head posture, and gaze direction disorders. To accurately diagnose the degree of depression of patients, this paper proposes a comprehensive framework, Cross-Channel Attentional Depression Detection Network, which can automatically diagnose the degree of depression of patients by inputting information from the facial images of depressed patients. Specifically, the comprehensive framework is composed of three main modules: (1) Face key point detection and cropping for video images based on Multi-Task Convolutional Neural Network. (2) The improved Feature Pyramid Networks model can fuse shallow features and deep features in video images and reduce the loss of miniscule features. (3) A proposed Cross-Channel Attention Convolutional Neural Network can enhance the interaction between tensor channel layers. Compared to other methods for automatic depression identification, a superior method was obtained by conducting extensive experiments on the depression dataset AVEC 2014, where the Root Mean Square Error and the Mean Absolute Error were 8.65 and 6.66, respectively.


Asunto(s)
Juicio , Médicos , Humanos , Movimiento , Redes Neurales de la Computación , Postura
11.
Sci Rep ; 14(1): 11865, 2024 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789592

RESUMEN

Chest X-ray (CXR) is an extensively utilized radiological modality for supporting the diagnosis of chest diseases. However, existing research approaches suffer from limitations in effectively integrating multi-scale CXR image features and are also hindered by imbalanced datasets. Therefore, there is a pressing need for further advancement in computer-aided diagnosis (CAD) of thoracic diseases. To tackle these challenges, we propose a multi-branch residual attention network (MBRANet) for thoracic disease diagnosis. MBRANet comprises three components. Firstly, to address the issue of inadequate extraction of spatial and positional information by the convolutional layer, a novel residual structure incorporating a coordinate attention (CA) module is proposed to extract features at multiple scales. Next, based on the concept of a Feature Pyramid Network (FPN), we perform multi-scale feature fusion in the following manner. Thirdly, we propose a novel Multi-Branch Feature Classifier (MFC) approach, which leverages the class-specific residual attention (CSRA) module for classification instead of relying solely on the fully connected layer. In addition, the designed BCEWithLabelSmoothing loss function improves the generalization ability and mitigates the problem of class imbalance by introducing a smoothing factor. We evaluated MBRANet on the ChestX-Ray14, CheXpert, MIMIC-CXR, and IU X-Ray datasets and achieved average AUCs of 0.841, 0.895, 0.805, and 0.745, respectively. Our method outperformed state-of-the-art baselines on these benchmark datasets.


Asunto(s)
Radiografía Torácica , Humanos , Radiografía Torácica/métodos , Redes Neurales de la Computación , Enfermedades Torácicas/diagnóstico por imagen , Enfermedades Torácicas/diagnóstico , Algoritmos , Diagnóstico por Computador/métodos
12.
J Asian Nat Prod Res ; 15(11): 1173-8, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24168329

RESUMEN

Microbial biotransformation of acetyl-11-keto-boswellic acid by Cunninghamella elegans AS 3.1207 was carried out, and totally four transformed products were isolated. On the basis of the extensive spectral data, their structures were characterized as 7ß-hydroxy-11-keto-boswellic acid (1), 7ß,30-dihydroxy-11-keto-boswellic acid (2), 7ß,16α-dihydroxy-3-acetyl-11-keto-boswellic acid (3), and 7ß,15α,21ß-trihydroxy-3-acetyl-11-keto-boswellic acid (4), respectively. Among them, products 1 and 2 are the new compounds.


Asunto(s)
Cunninghamella/metabolismo , Triterpenos/metabolismo , Animales , Biotransformación , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Estereoisomerismo , Triterpenos/química
13.
Multimed Tools Appl ; 82(12): 18635-18652, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36467439

RESUMEN

A single network model can't extract more complex and rich effective features. Meanwhile, the network structure is usually huge, and there are many parameters and consume more space resources, etc. Therefore, the combination of multiple network models to extract complementary features has attracted extensive attention. In order to solve the problems existing in the prior art that the network model can't extract high spatial depth features, redundant network structure parameters, and weak generalization ability, this paper adopts two models of Xception module and inverted residual structure to build the neural network. Based on this, a face expression recognition method based on improved depthwise separable convolutional network is proposed in the paper. Firstly, Gaussian filtering is performed by Canny operator to remove noise, and combined with two original pixel feature maps to form a three-channel image. Secondly, the inverted residual structure of MobileNetV2 model is introduced into the network structure. Finally, the extracted features are classified by Softmax classifier, and the entire network model uses ReLU6 as the nonlinear activation function. The experimental results show that the recognition rate is 70.76% in Fer2013 dataset (facial expression recognition 2013) and 97.92% in CK+ dataset (extended Cohn Kanade). It can be seen that this method not only effectively mines the deeper and more abstract features of the image, but also prevents network over-fitting and improves the generalization ability.

14.
Res Aging ; 45(5-6): 410-422, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35503011

RESUMEN

Global events that prime thoughts of proximity to death (e.g., the COVID-19 pandemic) can compress individuals' perceptions of future time horizons, and previous studies have found that compressed time horizons can be beneficial for older adults' well-being. However, findings from recent studies are mixed, and studies of well-being during the early months of COVID-19 show that older adults have fared comparatively well. The current study examines relationships between Future Time Perspective (FTP), COVID-19 impact, and purpose in life (PIL) among older Canadian women (N = 190; ages 59+). We expected that total FTP would be positively associated with PIL but that FTP subscales would be associated with PIL in different ways; COVID-19 impact would not be associated with PIL, but COVID-19 impact would moderate the FTP-PIL relationship. We found partial support for these hypotheses, as well as prevalence of social connection themes in open-ended question responses regarding COVID-19 impact.


Asunto(s)
COVID-19 , Pandemias , Humanos , Femenino , Anciano , Canadá , Tiempo
15.
JMIR Public Health Surveill ; 9: e48449, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37560940

RESUMEN

BACKGROUND: Little is known about trends in or projections of the disease burden of dietary gastric and esophageal cancer (GEC) in China. OBJECTIVE: We aim to report GEC deaths and disability-adjusted life years (DALYs) from 1990 to 2019, predict them through 2044, and decompose changes in terms of population growth, population aging, and epidemiological changes. METHODS: We retrieved dietary GEC data from the Global Burden of Disease (GBD) online database and used joinpoint regression and age-period-cohort models to analyze trends in dietary GEC deaths and DALYs from 1990 to 2019 in China. We used a Bayesian age period cohort model of integrated nested Laplace approximations to predict the disease burden of GEC through 2044 and obtained the estimated population of China from 2020 to 2050 from the Global Health Data Exchange website. Finally, we applied a recently developed decomposition method to attribute changes between 2019 and 2044 to population growth, population aging, and epidemiological changes. RESULTS: The summary exposure values and age-standardized rates decreased significantly from 1990 to 1999, with percentage changes of -0.06% (95% CI -0.11% to -0.02%) and -0.05% (95% CI -0.1% to -0.02%), respectively. From 1990 to 2019, for dietary esophageal cancer, the percentage change in age-standardized mortality rate (ASMR) was -0.79% (95% CI -0.93% to -0.58%) and the percentage change in age-standardized DALY rate (ASDR) was -0.81% (95% CI -0.94% to -0.61%); these were significant decreases. For dietary stomach cancer, significant decreases were also observed for the percentage change in ASMR (-0.43%, 95% CI -0.55% to -0.31%) and the percentage change in ASDR (-0.47%, 95% CI -0.58% to -0.35%). In addition, data from both the joinpoint regression and annual percentage change analyses demonstrated significantly decreasing trends for the annual percentage change in ASMR and ASDR for GEC attributable to dietary carcinogens. The overall annual percentage change (net drift) was -5.95% (95% CI -6.25% to -5.65%) for dietary esophageal cancer mortality and -1.97% (95% CI -2.11% to -1.83%) for dietary stomach cancer mortality. Lastly, in 2044, dietary esophageal cancer deaths and DALYs were predicted to increase by 192.62% and 170.28%, respectively, due to age structure (121.58% and 83.29%), mortality change (76.81% and 92.43%), and population size (-5.77% and -5.44%). In addition, dietary stomach cancer deaths and DALYs were predicted to increase by 118.1% and 54.08%, with age structure, mortality rate change, and population size accounting for 96.71% and 53.99%, 26.17% and 3.97%, and -4.78% and -3.88% of the change, respectively. CONCLUSIONS: Although the predicted age-standardized rates of mortality and DALYs due to dietary GEC show downward trends, the absolute numbers are still predicted to increase in the next 25 years due to rapid population aging in China.


Asunto(s)
Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Adulto , Neoplasias Esofágicas/epidemiología , Neoplasias Gástricas/epidemiología , Teorema de Bayes , China/epidemiología , Carcinógenos
16.
Patterns (N Y) ; 4(6): 100732, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37409054

RESUMEN

Accurate early detection of internal short circuits (ISCs) is indispensable for safe and reliable application of lithium-ion batteries (LiBs). However, the major challenge is finding a reliable standard to judge whether the battery suffers from ISCs. In this work, a deep learning approach with multi-head attention and a multi-scale hierarchical learning mechanism based on encoder-decoder architecture is developed to accurately forecast voltage and power series. By using the predicted voltage without ISCs as the standard and detecting the consistency of the collected and predicted voltage series, we develop a method to detect ISCs quickly and accurately. In this way, we achieve an average percentage accuracy of 86% on the dataset, including different batteries and the equivalent ISC resistance from 1,000 Ω to 10 Ω, indicating successful application of the ISC detection method.

17.
J Am Chem Soc ; 134(23): 9708-20, 2012 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-22554044

RESUMEN

(17)O-(1)H double resonance NMR spectroscopy was used to study the local structure of zeolite H-Mordenite. Different contact times were used in cross-polarization magic angle spinning (CPMAS) NMR, CP rotational-echo double resonance (CP-REDOR) NMR, and heteronuclear correlation (HETCOR) NMR spectroscopy to distinguish between Brønsted acid sites with different O-H distances. The accessibility of the various Brønsted acid sites was quantified by adsorbing the basic probe molecule trimethylphosphine in known amounts. On the basis of these experiments, locations of different Brønsted acid sites in H-Mordenite (H-MOR) were proposed. The use of (17)O chemical shift correlations to help assign sites is discussed.

18.
Int J Oral Maxillofac Implants ; 37(5): 869-878, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36170301

RESUMEN

PURPOSE: To assess the effect of nongrafted and grafted materials on transalveolar sinus floor elevation (TSFE) with implant placement. MATERIALS AND METHODS: Relevant studies published between January 1, 1994, and July 31, 2021, were selected by searching Embase, PubMed/MEDLINE, Web of Science, and Cochrane Central Register of Controlled Trials. The study subjects were restricted to humans, and the language was limited to English. The study was confined to randomized controlled trials, controlled clinical trials, and observational studies (prospective and retrospective cohort) related to TSFE with and without bone-grafting materials. Two reviewers independently extracted study data and conducted quality assessments according to the Cochrane handbook and NOS scale. RevMan 5.3 and Stata 15.1 software were then used to analyze the research data that met the inclusion criteria. RESULTS: A total of nine articles were included, including 421 implants in the graft group and 502 implants in the nongraft group. Meta-analysis showed that there was no significant difference in the implant failure rate (RR = 1.03, 95% CI: 1.00, 1.06, P = .08) or marginal bone loss (SMD = 0.06, 95% CI: -0.23, -0.35, P = .69) between implants with and without graft materials after TSFE. The amount of endosinus bone gain in the nongraft group was significantly lower than that in the graft group (SMD = -1.07, 95% CI: -1.73: -0.41, P = .0001). CONCLUSION: TSFE in implants with or without grafting can achieve similar results, but there may be more bone gain in TSFE with grafting.


Asunto(s)
Implantes Dentales , Elevación del Piso del Seno Maxilar , Implantación Dental Endoósea/métodos , Humanos , Seno Maxilar/cirugía , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Elevación del Piso del Seno Maxilar/métodos
19.
J Colloid Interface Sci ; 622: 1020-1028, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35567950

RESUMEN

For micron-sized nickel-based hydroxides sheets, the reaction and migration of anions/water molecules in the inner region tends to lag behind those along the edge, which can cause structure mismatch and capacity degradation during cycles. Nanosizing and structure design is a feasible solution to shorten the ion/electron path and improve the reaction homogeneity. Herein, this study reports a novel three-stage strategy (self-assembly of NiMn-LDH/ppy-C - reduction to NiMn/ppy-C - in situ phase transformation into NiMn/NiMn-LDH/ppy-C) to reduce the sheet size of NiMn-LDH to nanometer. Triggered by electrochemical activation, NiMn-LDH nanosheets can hereby easily and orderly grow on the exposed active (111) crystal plane of Ni to establish NiMn-LDH/NiMn heterostructure around ppy-C. Importantly, nanosizing and hierarchical structure play a synergistic role to maintain structural integrity and to promote the electron/mass transfer kinetics. The NiMn/NiMn-LDH/ppy-C composite delivers superior cycling stability with almost no decay of capacity retention after 40,000 cycles at 5 A g-1. Our hierarchical morphology modulation provides an ingenious, efficient way to boost the performance of Ni-based layered hydroxide materials.

20.
Adv Sci (Weinh) ; 9(4): e2103964, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34821481

RESUMEN

Soluble redox mediators (RMs), an alternative to conventional solid catalysts, have been considered an effective countermeasure to ameliorate sluggish kinetics in the cathode of a lithium-oxygen battery recently. Nevertheless, the high mobility of RMs leads to serious redox shuttling, which induces an undesired lithium-metal degeneration and RM decomposition during trade-off catalysis against the sustainable operation of batteries. Here, a novel carbon family of graphdiyne matrix is first proposed to decouple the charge-carrying redox property of ferrocene and the shuttle effects. It is demonstrated that a ferrocene-anchored graphdiyne framework can function as stationary RM, not only preserving the redox-mediating capability of ferrocene, but also promoting the local orientated three-dimensional (3D) growth of Li2 O2 . As a result, the RM-assisted catalysis in lithium-oxygen battery remains of remarkable efficiency and stability without the depletion of oxidized RMs or lithium degradation, resulting in a significantly enhanced electrochemical performance.

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