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1.
Small ; : e2311779, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38530085

RESUMEN

Micrometer-sized Si particles are beneficial to practical lithium-ion batteries in regard to low cost and high volumetric energy density in comparison with nanostructured Si anodes. However, both the issues of electrical contact loss and overgrowth of solid electrolyte interface for microscale Si induced by colossal volume change still remain to be addressed. Herein, a scalable and template-free method is introduced to fabricate yolk-shell structured Si anode from commercially available Si microparticles. The void is created via a one-step alkali etching process with the remaining silicon core as the yolk, and a double-walled shell is formed from simultaneous in situ growth of the conformal native oxide layer and subsequent carbon coating. In this configuration, the well-defined void spaces allow the Si core to expand without compromising structural integrity, while the double-walled shell acts as a static capsule to confine silicon fragments despite likely particle fracture. Therefore, electrical connectivity is maintained on both the particle and electrode level during deep galvanostatic cycling, and the solid-electrolyte interface is stabilized on the shell surface. Owing to the benefits of tailored design, excellent cycling stability (capacity retention of 95% after 100 cycles) and high coulombic efficiency (99.5%) are realized in a practical full-cell demonstration.

2.
Opt Express ; 32(3): 4603-4613, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297657

RESUMEN

The key to uncovering underlying fluid mechanisms lies in high-resolution and large-scale three-dimensional (3D) measurements of flow fields. Currently, the mainstream methods that are capable of volumetric measurements, such as tomographic background oriented schlieren and conventional plenoptic background oriented schlieren (plenoptic BOS), suffer system complexity and low axial resolution, respectively, prohibiting their application in high fidelity 3D flow measurement. This paper proposed an isotropic resolution plenoptic BOS (ISO plenoptic BOS) system that employed a mirror to create a second image view for the region of interest, thereby can achieve isotropic spatial resolution with only one camera. We comprehensively assessed the feasibility of the system by imaging the density field induced by candle flames, heat gun, and the Mach disk produced by the underexpanded jet through the high-pressure nozzle exit. All results proved that the dual-view plenoptic BOS system has higher axial resolution and can provide a more accurate 3D density field than the conventional system. As a BOS system that can achieve high-resolution volumetric imaging without the additional cost of cameras, data acquisition, hardware synchronization, and scanning, our ISO plenoptic BOS can expand the road to large-scale and high-resolution aerodynamic imaging.

3.
BMC Cancer ; 24(1): 133, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273249

RESUMEN

PURPOSE: There are limited and no standard therapies for recurrent glioblastoma. We herein report the antitumour activity and safety of sintilimab, bevacizumab and temozolomide (TMZ) in recurrent glioblastoma. METHODS: We retrospectively analysed eight patients with recurrent glioblastoma treated with sintilimab (200 mg) every three weeks + bevacizumab (10 mg/kg) every three weeks + TMZ (200 mg/m²orally) (5 days orally every 28 days for a total of four weeks). The primary objective was investigator-assessed median progression-free survival(mPFS). Secondary objectives were to assess the 6-month PFS, objective response rate (ORR) and duration of response (DOR) accroding to RANO criteria. RESULTS: The mPFS time for 8 patients was 3.340 months (95% CI: 2.217-4.463), The longest PFS was close to 9 months. Five patients were assessed to have achieved partial response (PR), with an overall remission rate of 62.5%, Four patients experienced a change in tumour volume at the best response time of greater than 60% shrinkage from baseline, and one patient remained progression free upon review, with a DOR of more than 6.57 months. The 6-month PFS was 25% (95% CI: 5.0-55.0%). Three patients had a treatment-related adverse events, though no grade 4 or 5 adverse events occurred. CONCLUSION: In this small retrospective study, the combination regimen of sintilimab, bevacizumab and TMZ showed promising antitumour activity in treatment of recurrent glioblastoma, with a good objective remission rate.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/uso terapéutico , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Bevacizumab/efectos adversos , Estudios Retrospectivos , Dacarbazina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología
4.
Environ Toxicol ; 37(8): 1853-1866, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35426242

RESUMEN

This study researched the function of long non-coding RNA LINC00365 in lung adenocarcinoma (LAD) progression. LINC00365, miR-429, and KCTD12 expression in the LAD clinical tissues and cells were detcetd by qRT-PCR and Western blot. LINC00365, miR-429, and KCTD12 effects on H1975 cells malignant phenotype were detected by cell counting kit-8 assay, clone formation experiment, Transwell experiment, and glycolysis. Dual luciferase reporter gene assay and RNA pull-down assay were implemented. LINC00365 effect on H1975 cells in vivo growth was detected. LINC00365 was low expressed in the LAD patients and cells, associating with poor outcome. LINC00365 up-regulation attenuated H1975 cells proliferation, migration, invasion, glycolysis and in vivo growth. LINC00365 inhibited KCTD12 expression by sponging miR-429. miR-429 up-regulation and KCTD12 down-regulation partial reversed LINC00365 inhibition on H1975 cells malignant phenotype. Thus, LINC00365 inhibited LAD progression and glycolysis via targeting miR-429/KCTD12 axis. LINC00365 might be a potential candidate for LAD target treatment clinically.


Asunto(s)
Adenocarcinoma del Pulmón , Adenocarcinoma , Neoplasias Pulmonares , MicroARNs , ARN Largo no Codificante , Adenocarcinoma/patología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Glucólisis/genética , Humanos , Neoplasias Pulmonares/patología , MicroARNs/genética , MicroARNs/metabolismo , Proteínas/genética , Proteínas/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
5.
BMC Evol Biol ; 16: 73, 2016 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-27068356

RESUMEN

BACKGROUND: The South China landmass has been characterized by a complex geological history, including mountain lifting, climate changes, and river capture/reversal events. To determine how this complexity has influenced the landmass's phylogeography, our study examined the phylogeography of Garra orientalis, a cyprinid widely distributed in South China, using sequences from the mitochondrial DNA control region and cytochrome b gene (1887 bp) and polymorphisms of thirteen microsatellite loci. RESULTS: In total, 157 specimens were collected from eight populations. All 88 mtDNA haplotypes were identified as belonging to three major lineages, and these lineages were almost allopatric in their distributions. The results of a statistical dispersal-vicariance analysis suggested that the ancestral populations of G. orientalis were distributed south of the Yunkai Mountains, including on Hainan Island. The mtDNA data revealed a strong relationship between phylogeny and geography. In the microsatellite analysis, a total of 339 alleles with an average of 26 alleles per locus were observed across thirteen microsatellite loci. A clustering algorithm for microsatellite data revealed an admixture-like genetic structure. Although the mtDNA and microsatellite data sets displayed a discordant population structure, the results of an approximate Bayesian computation approach showed that these two markers revealed congruent historical signals. The population history of G. orientalis reflects vicariance events and dispersal related to the complex geological history of South China. CONCLUSION: Our results (i) found that the discordances between mtDNA and microsatellite markers were accounted for by admixtures; (ii) showed that the Wuzhishan and Yinggeling mountain ranges and Qiongzhou Strait were important barriers limiting gene exchange between populations on both sides; (iii) indicated that during glaciation and inter-glacial periods, the strait and continental shelves were exposed and sank, which contributed with the dispersion and differentiation of populations; and (iv) displayed that the admixtures between lineages took place in coastal populations and then colonized the tributaries of the Pearl River.


Asunto(s)
Cyprinidae/genética , Animales , Teorema de Bayes , China , Citocromos b/genética , ADN Mitocondrial/genética , Genética de Población , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Filogenia , Filogeografía , Polimorfismo Genético
6.
Biochem Biophys Res Commun ; 457(4): 572-7, 2015 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-25603047

RESUMEN

In the past decade, monoclonal antibodies (mAbs) have revolutionized the treatment of non-Hodgkin lymphomas (NHLs). Although Fc-dependent mechanisms of mAb-mediated tumor clearance have been extensively studied, the ability of mAbs to directly evoke programmed cell death (PCD) and the underlying mechanisms involved remain unclear. It is well established that type II anti-CD20 mAb (Tositumomab) potently evoked PCD through a caspases-independent, lysosome-mediated process, which is related to homotypic adhesion (HA) in NHL cell lines. Herein, we reveal that the induction of ceramide generation by anti-CD20 mAbs directly correlates with their ability to induce PCD. The inhibition of ceramide abrogated Tositumomab-induced PCD indicating that ceramide is required for the execution of cell death. Further experimental results revealed that ceramide was generated downstream of mAb-induced HA and upstream of lysosome leakage. These findings provide further insights into a previously unrecognized role for ceramide generation in mediating PCD evoked by type II anti-CD20 mAbs in Burkitt's lymphoma cells. This newly characterized cell death pathway may potentially be exploited to eliminate malignant cells.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antígenos CD20/inmunología , Antineoplásicos/farmacología , Linfoma de Burkitt/tratamiento farmacológico , Ceramidas/inmunología , Lisosomas/efectos de los fármacos , Anticuerpos Monoclonales/inmunología , Antineoplásicos/inmunología , Linfoma de Burkitt/inmunología , Linfoma de Burkitt/patología , Caspasas/inmunología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , Lisosomas/inmunología , Lisosomas/patología , Transducción de Señal/efectos de los fármacos
7.
Phys Chem Chem Phys ; 17(27): 17562-5, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-26082288

RESUMEN

Yolk-shell Si@void@C nanocomposites are prepared via a facile method of resorcinol-formaldehyde coating and LiOH etching, without SiO2 pre-modification on Si particles, expensive carbon sources, or environmentally-unfriendly HF solutions. Profiting from these favorable features, Si@void@C nanocomposites exhibit considerable reversible capacities (628 mA h g(-1) after 100 cycles) and good rate performances.

8.
Chemistry ; 20(17): 5046-53, 2014 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-24644032

RESUMEN

Highly dispersed Ni nanoparticles (NPs) and abundant functional N-species were integrated into ultrathin carbon nanosheets by using a facile and economical sol-gel route. Embedded- and anchored-type configurations were achieved for the dispersion of Ni NPs in/on N-rich carbon nanosheets. The anchored-type composite exhibited outstanding pseudocapacitance of 2200 F g(-1) at 5 A g(-1) with unusual rate capability and extraordinary cyclic stability over 20 000 cycles with little capacitance decay. Aqueous asymmetric supercapacitors fabricated with this composite cathode demonstrated a high energy density of 51.3 Wh kg(-1) at a relatively large power density of 421.6 W kg(-1) , along with outstanding cyclic stability. This approach opens an attractive direction for enhancing the electrochemical performances of metal-based supercapacitors and can be generalized to design high-performance energy-storage devices.

9.
ACS Appl Mater Interfaces ; 16(7): 8802-8812, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38319879

RESUMEN

Silicon (Si) stands out as a highly promising anode material for next-generation lithium-ion batteries. However, its low intrinsic conductivity and the severe volume changes during the lithiation/delithiation process adversely affect cycling stability and hinder commercial viability. Rational design of electrode architecture to enhance charge transfer and optimize stress distribution of Si is a transformative way to enhance cycling stability, which still remains a great challenge. In this work, we fabricated a stable integrated Si electrode by combining two-dimensional graphene sheets (G), one-dimensional Si nanowires (SiNW), and carbon nanotubes (CNT) through the cyclization process of polyacrylonitrile (PAN). The integrated electrode features a G/SiNW framework enveloped by a conformal coating consisting of cyclized PAN (cPAN) and CNT. This configuration establishes interconnected electron and lithium-ion transport channels, coupled with a rigid-flexible encapsulated coating, ensuring both high conductivity and resistance against the substantial volume changes in the electrode. The unique multidimensional structural design enhances the rate performance, cyclability, and structural stability of the integrated electrode, yielding a gravimetric capacity (based on the total mass of the electrode) of 650 mAh g-1 after 1000 cycles at 3.0 A g-1. When paired with a commercial LiNi0.5Co0.2Mn0.3O2 cathode, the resulting full cell retains 84.8% of its capacity after 160 cycles at 2.0 C and achieves an impressive energy density of 435 Wh kg-1 at 0.5 C, indicating significant potential for practical applications. This study offers valuable insights into comprehensive electrode structure design at the electrode level for Si-based materials.

10.
Front Cardiovasc Med ; 11: 1393440, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39105079

RESUMEN

Introduction: Although angiotensin receptor-neprilysin inhibitor (ARNI) has shown promise in patients with heart failure and reduced ejection fraction (HFrEF), the treatment effect in HFrEF patients with end-stage renal disease (ESRD) undergoing dialysis is uncertain. This study aimed to examine the real-world effects of ARNI vs. angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEI/ARB) in this subpopulation. Methods: This multi-institutional, retrospective study identified 349 HFrEF patients with ESRD on dialysis, who initiated either ARNI or ACEI/ARB therapy. Efficacy outcomes included rates of hospitalization for heart failure (HHF) and mortality, as well as changes in echocardiographic parameters. Safety outcomes encompassed hypotension and hyperkalemia. Treatment effects were assessed using Cox proportional hazards models, with additional sensitivity analyses for robustness. Results: Out of 349 patients screened, 89 were included in the final analysis (42 in the ARNI group and 47 in the ACEI/ARB group). After 1 year of treatment, echocardiographic measures between the two groups were comparable. The primary composite rate of HHF or mortality was 20.6 events per 100 patient-years in the ARNI group and 26.1 in the ACEI/ARB group; the adjusted hazard ratio was 0.98 (95% CI: 0.28-3.43, P = 0.97). Their safety outcomes did not differ significantly. Sensitivity analyses, including repetitive sampling, propensity score matching, and extended follow-up, corroborated these findings. Conclusion: ARNI has proven effective in treating HFrEF patients; however, significant benefits were not observed in these patients with ESRD undergoing dialysis compared with ACEI/ARB in this real-world cohort. Future research employing a more extended follow-up period, larger sample size, or randomized design is warranted to investigate the treatment effects in this subpopulation.

11.
J Atheroscler Thromb ; 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38092392

RESUMEN

AIMS: Critical limb ischemia (CLI) is an emerging public health threat and lacks a reliable score for predicting the outcomes. The Age, Body Mass Index, Chronic Kidney Disease, Diabetes, and Genotyping (ABCD-GENE) risk score helps identify patients with coronary artery disease who have cytochrome P450 2C19 (CYP2C19) polymorphism-related drug resistance and are at risk for cardiovascular adverse events. However, its application to CLI remains unknown. In this study, we aim to validate a modified ACD-GENE-CLI score to improve the prediction of major adverse limb events (MALEs) in patients with CLI receiving clopidogrel. METHODS: Patients with CLI receiving clopidogrel post-endovascular intervention were enrolled prospectively in two medical centers. Amputation and revascularization as MALEs were regarded as the outcomes. RESULTS: A total of 473 patients were recruited, with a mean follow-up duration of 25 months. Except for obesity, old age, diabetes, chronic kidney disease (CKD), and CYP2C19 polymorphisms were significantly associated with MALEs. Using bootstrap regression analysis, we established a modified risk score (ACD-GENE-CLI) that included old age (≥ 65 years), diabetes, CKD, and CYP2C19 polymorphisms. At a cutoff value of 8, the ACD-GENE-CLI score was superior to the CYP2C19 deficiency only, and the conventional ABCD-GENE score in predicting MALEs (area under the curve: 0.69 vs. 0.59 vs. 0.67, p=0.01). The diagnostic ability of the ACD-GENE-CLI score was consistent in the external validation. Also, Kaplan-Meier curves showed that in CYP2C19 deficiency, the ABCD-GENE and ACD-GENE-CLI scores could all differentiate patients with CLI who are free from MALEs. CONCLUSIONS: The modified ACD-GENE-CLI score could differentiate patients with CLI receiving clopidogrel who are at risk of MALEs. Further studies are required to generalize the utility of the score.

12.
Front Chem ; 10: 882681, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35464200

RESUMEN

Silicon is considered as the most promising candidate for anodes of next generation lithium-ion batteries owing to its natural abundance and low Li-uptake potential. Building a macroporous structure would alleviate the volume variation and particle fracture of silicon anodes during cycling. However, the common approaches to fabricate macroporous silicon are complex, costly, and high energy-consuming. Herein, bamboo leaves are used as a sustainable and abundant resource to produce macroporous silicon via a scalable magnesiothermic reduction method. The obtained silicon inherits the natural interconnected network from the BLs and the mesopores from the BL-derived silica are engineered into macropores by selective etching after magnesiothermic reduction. These unique structural advantages lead to superior electrochemical performance with efficient electron/ion transport and cycling stability. The macroporous Si@C composite anodes deliver a high capacity of 1,247.7 mAh g-1 after 500 cycles at a current density of 1.0 A g-1 with a remarkable capacity retention of 98.8% and average Coulombic efficiency as high as 99.52% for the same cycle period. Furthermore, the rate capabilities of the Si@C composites are enhanced by conformal carbon coating, which enables the anode to deliver a capacity of 538.2 mAh g-1 at a high current density of 4.0 A g-1 after 1,000 deep cycles. Morphology characterization verifies the structural integrity of the macroporous Si@C composite anodes. This work demonstrated herein provides a simple, economical, and scalable route for the industrial production of macroporous Si anode materials utilizing BLs as a sustainable source for high-performance LIBs.

13.
ACS Appl Mater Interfaces ; 14(36): 40975-40984, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36049121

RESUMEN

Many challenges still exist in lithium-oxygen batteries (LOBs), particularly exploring an efficient catalyst to optimize the reaction pathway and regulate the Li2O2 nucleation. Pr6O11 has a unique 4f electronic structure and the highest oxygen ion mobility among rare earth oxides, exhibiting superior electronic, optical, and chemical properties. These unique properties might endow it with advanced catalytic activities for LOBs. This work reports two crystal forms of Pr6O11 as novel catalysts and regulates the oxygen vacancy (Vo) concentrations by feasible calcination. Thermogravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS) confirm the conversion from commercial Pr6O11 to cubic fluorite Pr6O11 and Vo-rich Pr6O11. Photographs, high-resolution transmission electron microscopy, selected area electron diffraction, XPS, and electron paramagnetic resonance robustly demonstrate the temperature-dependent evolution of Vo. Ex situ XPS, scanning electron microscopy, and electrochemical techniques are used to study the catalytic mechanism and electrochemical reversibility. It is found that an appropriate Vo concentration can boost O2 adsorption/desorption, accelerate electron transport, and reduce the reaction energy barrier. Vo-rich Pr6O11 optimizes the reaction pathway by offering an intermediate Li2-xO2 (with metalloid conductivity) and adjusting Li2O2 into vertically staggered nanoflakes, effectively avoiding the suffocation of the catalytic surface and presenting excellent capacity, cycling stability, and rate performance.

14.
ACS Appl Mater Interfaces ; 13(44): 52519-52529, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34719234

RESUMEN

The in situ growth of active materials on 3D current collectors (such as Ni foams) presents facile and efficient access to high-performance supercapacitors. However, the low surface area of current collectors limits the mass loading, microstructure, and capacitive performance of active materials thereon. Herein, we develop a novel surface modification with hierarchical N-rich carbon nanosheets on Ni foams via a simple sol-gel method. At the same time, its favorable effects on mass loading and utilization are demonstrated using NiCoMn-carbonate hydroxide (NCM) as a model active material. Specifically, the carbon modification greatly boosts the current collector's specific surface area and enables the growth of dense NCM nanoneedles with controllable mass loading ranging from 5.2 to 23.1 mg cm-2. Meanwhile, the correlation between mass loading and utilization is systematically studied, which shows the well-maintained energy storage efficiency due to the conducive surface modification. As a result, excellent performance with the ultrahigh area-specific capacity of 19.36 F cm-2 at 2 mA cm-2 in the three-electrode configuration and remarkable area-specific energy density of 1352 µW h cm-2 in the solid-state asymmetric device can be achieved, demonstrating a prospective pathway toward facile and effective current collector designs for high-energy/power-density supercapacitors.

15.
DNA Cell Biol ; 38(8): 808-813, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31335167

RESUMEN

This study aims to investigate whether a relationship exists between the C3435T polymorphism of ABCB1 gene and poststroke depression (PSD). A total of 82 PSD patients and 115 nondepression patient (NPSD) controls were included in this study. All patients were evaluated using the Hamilton Rating Scale for Depression to determine the severity of depression and complete the packet. PSD patients were diagnosed in accordance with the DSM-V criteria. The C3435T polymorphism of ABCB1 was genotyped through fluorescence in situ hybridization and chromosome karyotype analysis system. The PSD (n = 82) and NPSD groups (n = 115) had a total prevalence rate of 41.6%. The prevalence of PSD in men was 58.5%, whereas that in women was 41.5%, and no statistically significant difference existed between the two groups (χ2 = 1.009; p = 0.315). The CC, CT, and TT frequencies of the PSD group were 26.8%, 47.6%, and 25.6%, respectively, whereas those of the NPSD group were 42.6%, 45.2%, and 12.2%, respectively. Based on the CC genotype, the relative risk of homozygous mutant TT was 3.341 (χ2 = 7.869; p = 0.005; OR = 3.341), and the T allele frequency in the PSD group was 49.4% higher than that in the NPSD group. The locus gene frequency was 34.8%, and the relative risk of allele T relative to allele C was 1.830 (χ2 = 8.381; p = 0.004; OR = 1.830). A certain correlation exists between the C3435T gene polymorphism and PSD in the Han population in South Anhui Province, China, and further studies are needed to confirm our findings.


Asunto(s)
Depresión/genética , Polimorfismo Genético , Accidente Cerebrovascular/psicología , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Pueblo Asiatico/genética , China , Depresión/etiología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones
16.
Materials (Basel) ; 12(24)2019 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-31835409

RESUMEN

Nano-sized spinel LiMn2O4/carbon nanotubes (LMO/CNTs) composite is facilely synthesized via a one-step dynamic hydrothermal approach. The characterizations and electrochemical measurements reveal that LiMn2O4 particles with narrow size distribution are well dispersed with CNTs in the composite. The LMO/CNTs nanocomposite with 5 wt % CNTs displays a high specific discharge capacity of 114 mAh g-1 at 1C rate, and the retention rate after 180 cycles at room temperature reaches 94.5% in the potential window of 3.3 to 4.3 V vs. Li/Li+. Furthermore, the electrochemical performance of the composite with 5 wt % CNTs at elevated temperature (55 °C) is also impressive, 90% discharging capacity could be maintained after 100 cycles at 1C. Such excellent electrochemical performance of the final product is attributed to the content of CNTs added in the hydrothermal process and small particle size inherited from pretreated MnO2 precursor.

17.
ChemistryOpen ; 8(3): 298-303, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30886787

RESUMEN

In this work, we introduce Ni nanopyramid arrays (NPAs) supported amorphous Ge anode architecture and demonstrate its effective improvement in sodium storage properties. The Ni-Ge NPAs are prepared by facile electrodeposition and sputtering method, which eliminates the need for any binder or conductive additive when used as a Na-ion battery anode. The electrodes display stable cycling performance and enhanced rate capabilities in contrast with planar Ge electrodes, which can be owing to the rational design of the architectured electrodes and firm bonding between current collector and active material (i. e. Ni and Ge, respectively). To validate improvement of nanostructures on electrochemical performance, sodium insertion behavior of crystalline Ge derived from Mg2Ge precursor has been investigated, in which limited but effective enhancement of sodium storage properties are realized by introducing porous nanostructure in crystalline Ge. These results show that elaborately designed configuration of Ge electrodes may be a promising anode for Na-ion battery applications.

18.
Beilstein J Nanotechnol ; 10: 2207-2216, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31807406

RESUMEN

Transition metal compounds such as nickel cobalt sulfides (Ni-Co-S) are promising electrode materials for energy storage devices such as supercapacitors owing to their high electrochemical performance and good electrical conductivity. Developing ultrathin nanostructured materials is critical to achieving high electrochemical performance, because they possess rich active sites for electrochemical reactions, shortening the transport path of ions in the electrolyte during the charge/discharge processes. This paper describes the synthesis of ultrathin (around 10 nm) flower-like Ni1- x Co x S2 nanoflakes by using templated NiCo oxides. The as-prepared Ni1- x Co x S2 material retained the morphology of the initial NiCo oxide material and exhibited a much improved electrochemical performance. The Ni1- x Co x S2 electrode material exhibited a maximum specific capacity of 1066.8 F·g-1 (533.4 C·g-1) at 0.5 A·g-1 and a capacity retention of 63.4% at 20 A·g-1 in an asymmetric supercapacitor (ASC). The ASC showed a superior energy density of 100.5 Wh·kg-1 (at a power density of 1.5 kW·kg-1), an ultrahigh power density of 30 kW·kg-1 (at an energy density of 67.5 Wh·kg-1) and excellent cycling stability. This approach can be a low-cost way to mass-produce high-performance electrode materials for supercapacitors.

19.
Thorac Cancer ; 8(1): 46-50, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27910227

RESUMEN

BACKGROUND: The non-recurrent laryngeal nerve (NRLN) is a rare but potentially serious anomaly that is commonly associated with the aberrant right subclavian artery (ARSA). It is easy to damage during surgical resection of esophageal cancer, leading to severe complications. METHODS: Preoperative enhanced thoracic computed tomography (CT) scans of 2697 patients with esophageal carcinoma treated in our hospital between January 2010 and December 2013 were examined. We classified the positional relationship between the right subclavian artery and the membranous wall of the trachea into two types and used this method to predicate NRLN by identifying ARSA. RESULTS: Twenty-six patients (0.96%) were identified with ARSA, all of which were cases of NRLN by CT. NRLN was identified during surgery in the 26 patients, and a normal right recurrent laryngeal nerve was observed in 2671 patients. The ARSA was detected on the dorsal side of the membranous wall of the trachea in all 26 NRLN cases, while it was detected on the ventral side in all 2671 recurrent laryngeal nerve cases. CONCLUSION: Enhanced CT scanning is a reliable method for predicting NRLN by identifying ARSA. Preoperative recognition of this nerve anomaly allows surgeons to avoid damaging the nerve and abnormal vessels during esophagectomy.


Asunto(s)
Aneurisma/diagnóstico por imagen , Anomalías Cardiovasculares/diagnóstico por imagen , Enfermedades de los Nervios Craneales/diagnóstico por imagen , Trastornos de Deglución/diagnóstico por imagen , Neoplasias Esofágicas/cirugía , Nervio Laríngeo Recurrente/anomalías , Arteria Subclavia/anomalías , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Neoplasias Esofágicas/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodo Preoperatorio , Estudios Retrospectivos , Arteria Subclavia/diagnóstico por imagen
20.
ACS Appl Mater Interfaces ; 8(51): 35172-35179, 2016 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-27959502

RESUMEN

The challenging problems of SnO2 anode material for lithium ion batteries are the poor electronic conductivity and the low oxygen reutilization due to the irreversibility of Li2O generated in the initial discharge leading to a theoretical initial Coulombic efficiency (ICE) of only 52.4%. Different from these strategies, this work proposes a novel strategy to level up the oxygen reutilization in SnO2 by introducing Co3Sn2 nanoalloys which can release Co atoms to reversibly react with Li2O instead. According to this protocol, multi-yolk-shell SnO2/Co3Sn2@C nanocubes are designed and successfully prepared using hollow CoSn(OH)6 nanocubes as precursors followed a hydrothermal carbon coating and calcination treatment. The unique multi-yolk-shell nanostructure offers adequate breathing space for the volumetric deformation during long-term cycling. Moreover, the removal of Li2O allows a high electronic conductivity and resultant rate performance. As a result, the efficient reutilization of oxygen enables a high ICE of 71.7% and a reversible capacity of 1003 mA h g-1 after 200 cycles at 100 mA g-1. Cyclic voltammetry, cycling performance at different voltage windows, and X-ray photoelectron spectroscopy confirm the proposed mechanism. This strategy employing oxygen-poor metals or alloys provides a novel approach to enhance the oxygen reutilization in SnO2 for higher reversibility.

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