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1.
Chinese Journal of Cardiology ; (12): 742-749, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-984712

RESUMO

Objective: To explore the long-term clinical efficacy of transcatheter repair of mitral paravalvular leak (PVL) post surgical mitral valve replacement. Methods: This study is a retrospective study. Patients who completed transcatheter repair of paravalvular leak after surgical mitral valve replacement at Shanghai Chest Hospital, Shanghai Jiaotong University School of Medicine from March 2010 to December 2018 were included. Technical success was defined as the occluder being stably implanted in the paravalvular leak site without affecting the function of the mitral valve and surrounding tissues; and there were no intervention-related complications, such as new hemolysis or aggravated hemolysis, and echocardiography confirmed mitral paravalvular regurgitation reduced by more than 1 grade. Patients were followed up at 30 days, 1, and 3 years after the intervention. The main endpoints were all-cause death and re-surgery due to interventional failure or serious complications. The occurrence of occluder-mediated hemolysis and chronic renal insufficiency was recorded, and patients were monitored with echocardiography during follow up. Results: A total of 75 patients were included, aged (54.3±22.9) years old, and 38 patients were males. All patients had decreased cardiac function and/or hemolysis before intervention. Procedural success was achieved in 54 patients (72.0%). Incidence of device-mediated hemolysis was 18.7% (14/75). During the follow-up period, all-cause death occurred in 7 patients (9.3%), and 3 were cardiac deaths.The 3-year event-free survival rate was 81.3% (61/75). The need for cardiac surgery was 9.3% (7/75): 3 cases due to severe device-mediated hemolysis, 2 cases due to prosthetic valve failure and 2 cases due to moderate to severe residual regurgitation. The echocardiography follow-up results showed that the position of the occluder was stable, there was no impact on the artificial valve function and surrounding structures, and the residual regurgitation was stable without progressive increase in event-free patients. Compared with pre-intervention, the left ventricular end systolic diameter ((33.9±7.4)mm vs. (38.3±8.9) mm, P=0.036), end diastolic diameter ((53.7±8.3) mm vs. (58.4±9.1) mm, P=0.045) and left atrial diameter (59.3 (44.5, 90.7) mm vs. 64.3 (44.8, 96.6) mm, P=0.049) were significantly reduced, pulmonary artery systolic pressure was also significantly decreased ((36.5±15.8) mmHg vs. (46.3±14.9) mmHg, P=0.022, 1 mmHg=0.133 kPa). There was no significant difference between 3 years and 1 year after transcatheter repair of mitral paravalvular leak post surgical mitral valve replacement (all P>0.05). Conclusion: Transcatheter repair of mitral paravalvular leak post surgical mitral valve replacement is an effective treatment option in selective patients.


Assuntos
Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Valva Mitral/cirurgia , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Estudos Retrospectivos , Hemólise , China , Insuficiência da Valva Mitral/cirurgia , Resultado do Tratamento , Cateterismo Cardíaco , Falha de Prótese
2.
Pacing Clin Electrophysiol ; 45(4): 535-555, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35032332

RESUMO

The left atrial appendage closure (LAAC), the efficacy and safety of which has been proved by a number of randomized controlled trials and registries, is recommended by several guidelines to prevent stroke in high-risk patients with non-valvular atrial fibrillation. However, current guidelines only discuss the indications and contraindications of LAAC, as an emerging technology, there still lacks comprehensive recommendations involved with LAAC, including devices, image assessment modality, identification and treatment of complications, perioperative medication, and postoperative management. Therefore, the Chinese Society of Cardiology (CSC) of Chinese Medical Association (CMA) and the Editorial Board of Chinese Journal of Cardiology jointly issued the expert consensus statement on LAAC in the prevention of stroke in patients with atrial fibrillation after comprehensive discussion by experts with different backgrounds. This consensus provided three levels of recommendations to guide and standardize the clinical application of LAAC based on existing evidence and clinical practice experience, including appropriate (more potential benefits or fewer harms), uncertain (somehow reasonable but need more evidence), and inappropriate (unlikely to benefit, or have more complications).


Assuntos
Apêndice Atrial , Fibrilação Atrial , Procedimentos Cirúrgicos Cardíacos , Acidente Vascular Cerebral , Apêndice Atrial/cirurgia , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , China , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/prevenção & controle , Resultado do Tratamento
3.
BMC Cardiovasc Disord ; 22(1): 4, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996365

RESUMO

BACKGROUND: Risk stratification in non-ST segment elevation myocardial infarction (NSTEMI) determines the intervention time. Limited study compared two risk scores, the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) risk scores in the current East Asian NSTEMI patients. METHODS: This retrospective observational study consecutively collected patients in a large academic hospital between 01/01 and 11/01/2017 and followed for 4 years. Patients were scored by TIMI and GRACE scores on hospital admission. In-hospital endpoints were defined as the in-hospital composite event, including mortality, re-infarction, heart failure, stroke, cardiac shock, or resuscitation. Long-term outcomes were all-cause mortality and cardiac mortality in 4-year follow-up. RESULTS: A total of 232 patients were included (female 29.7%, median age 67 years), with a median follow-up of 3.7 years. GRACE score grouped most patients (45.7%) into high risk, while TIMI grouped the majority (61.2%) into medium risk. Further subgrouping the TIMI medium group showed that half (53.5%) of the TIMI medium risk population was GRACE high risk (≥ 140). Compared to TIMI medium group + GRACE < 140 subgroup, the TIMI medium + GRACE high-risk (≥ 140) subgroup had a significantly higher in-hospital events (39.5% vs. 9.1%, p < 0.05), long-term all-cause mortality (22.2% vs. 0% p < 0.001) and cardiac death (11.1% vs. 0% p = 0.045) in 4-year follow-up. GRACE risk scores showed a better predictive ability than TIMI risk scores both for in-hospital and long-term outcomes. (AUC of GRACE vs. TIMI, In-hospital: 0.82 vs. 0.62; long-term mortality: 0.89 vs. 0.68; long-term cardiac mortality: 0.91 vs. 0.67, all p < 0.05). Combined use of the two risk scores reserved both the convenience of scoring and the predictive accuracy. CONCLUSION: GRACE showed better predictive accuracy than TIMI in East Asian NSTEMI patients in both in-hospital and long-term outcomes. The sequential use of TIMI and GRACE scores provide an easy and promising discriminative tool in predicting outcomes in NSTEMI East Asian patients.


Assuntos
Infarto do Miocárdio sem Supradesnível do Segmento ST/epidemiologia , Sistema de Registros , Medição de Risco/métodos , Terapia Trombolítica/métodos , Idoso , China/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/tratamento farmacológico , Infarto do Miocárdio sem Supradesnível do Segmento ST/mortalidade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo
4.
ACS Appl Mater Interfaces ; 13(46): 54997-55006, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34756035

RESUMO

Nickel-rich layered oxides have been regarded as a potential cathode material for high-energy-density lithium-ion batteries because of the high specific capacity and low cost. However, the rapid capacity fading due to interfacial side reactions and bulk structural degradation seriously encumbers its commercialization. Herein, a highly stable hybrid surface architecture, which integrates an outer coating layer of TiO2&Li2TiO3 and a surficial titanium doping by incorporated Ti2O3, is carefully designed to enhance the structural stability and eliminate lithium impurity. Meanwhile, the surficial titanium doping induces a nanoscale cation-mixing layer, which suppresses transition-metal-ion migration and ameliorates the reversibility of the H2 → H3 phase transition. Also, the Li2TiO3 coating layer with three-dimensional channels promotes ion transportation. Moreover, the electrochemically stable TiO2 coating layer restrains side reactions and reinforces interfacial stability. With the collaboration of titanium doping and TiO2&Li2TiO3 hybrid coating, the sample with 1 mol % modified achieves a capacity retention of 93.02% after 100 cycles with a voltage decay of only 0.03 V and up to 84.62% at a high voltage of 3.0-4.5 V. Furthermore, the ordered occupation of Ni ions in the Li layer boosts the thermal stability by procrastinating the layered-to-rock salt phase transition. This work provides a straightforward and economical modification strategy for boosting the structural and thermal stability of nickel-rich cathode materials.

5.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3370-3376, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34658224

RESUMO

We examined the distribution of melanin during the development of the larvae of Schizothorax o'connori except the eyes with histological method. The results showed that after hatching, the appearance sequence of melanin in different organs were following an order of the outer membrane of neurocranium, the pericardial cavity and the dorsal skin, and the peritoneum and the spinal cord. Specifically, melanin appeared in the outer membrane of neurocranium around 5 DAH (days after hatching), in the pericardial cavity and the back skin at 7 DAH, and in the peritoneum and the spinal cord at 10 DAH. Melanin was found in the skin and internal organs (the outer membrane of neurocranium, the pericardial cavity, the peritoneum, the spinal cord) of S. o'connori at 10 DAH, which was mainly distributed on the back. The appearance and distribution of melanin in the postembryonic development of S. o'connori might be related to the high ultraviolet radiation. Our results could provide reference for further research on the UV protection mechanism of melanin for fish and provide theoretical support for the optimization of rearing conditions for larvae in the plateau.


Assuntos
Cyprinidae , Melaninas , Animais , Larva , Raios Ultravioleta
6.
ACS Appl Mater Interfaces ; 13(8): 10064-10070, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33591734

RESUMO

A binder is an important component in lithium-ion batteries and plays a significant role in maintaining the properties of active substances. Most studies in the field of binders have only focussed on physical properties such as bonding performance. Here, a polyacrylic acid-modified binder was designed and adapted to Li[Ni0.8Co0.1Mn0.1]O2, which enhanced the electrochemical stability of Li[Ni0.8Co0.1Mn0.1]O2 from 30.2 to 66.6% (300 cycles at 1 C). We for the first time discovered that this was caused by a chemical reaction between polyacrylic acid and the residual lithium on the surface during the cycling, which formed a lithium propionic acid coating layer and maintained the stability of the layered structure.

7.
Adv Sci (Weinh) ; 7(11): 1903279, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32537402

RESUMO

Metal sulfides have been intensively investigated for efficient sodium-ion storage due to their high capacity. However, the mechanisms behind the reaction pathways and phase transformation are still unclear. Moreover, the effects of designed nanostructure on the electrochemical behaviors are rarely reported. Herein, a hydrangea-like CuS microsphere is prepared via a facile synthetic method and displays significantly enhanced rate and cycle performance. Unlike the traditional intercalation and conversion reactions, an irreversible amorphization process is evidenced and elucidated with the help of in situ high-resolution synchrotron radiation diffraction analyses, and transmission electron microscopy. The oriented (006) crystal plane growth of the primary CuS nanosheets provide more channels and adsorption sites for Na ions intercalation and the resultant low overpotential is beneficial for the amorphous Cu-S cluster, which is consistent with the density functional theory calculation. This study can offer new insights into the correlation between the atomic-scale phase transformation and macro-scale nanostructure design and open a new principle for the electrode materials' design.

8.
ACS Appl Mater Interfaces ; 12(9): 10240-10251, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32027108

RESUMO

Ni-rich cathodes LiNixCoyAl1-x-yO2 (0.8 < x < 1) with high energy density, environmental benignity, and low cost are regarded as the most promising candidate materials for next-generation lithium batteries. Unfortunately, capacity fading derived from unstable surface properties and intrinsic structural instability under extreme conditions limits large-scale commercial utilization. Herein, an interface-regulated Ni-rich cathode material LiNi0.87Co0.10Al0.03O2 with a layer (R3̅m) core, a NiO salt-like (Fm3̅m) phase, and an ultrathin amorphous ion-conductive LiBO2 (LBO) layer is constructed by gradient boron incorporation and lithium-reactive coating during calcination. The ultrathin LBO layer not only exhausts residual lithium species but also acts as a layer for Li+ transport and insulation of detrimental reaction. The NiO salt-like phase in the subsurface could enhance the structural stability of the layer core for the pillar effects. With the positive role provided by the functional hybrid surface layer and boron doping, the modified cathode exhibits enhanced Li+ conductivity, structural stability, reversibility of the H2-H3 phase transition, suppressed side reactions, ameliorated transition-metal dissolution, and excellent electrochemical performance. Especially, a 1% wt boron-modified cathode delivers a discharge capacity of 211.99 mA h g-1 in the potential range of 3.0-4.3 V at 0.2 C and excellent cycle life with a capacity retention of 89.43% after 200 cycles at 1 C.

9.
ACS Appl Mater Interfaces ; 12(7): 8146-8156, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31916744

RESUMO

Injection of phase transition from a layered to rock-salt phase into the bulk lattice and side reactions on the interfacial usually causes structure degradation, quick capacity/voltage decay, and even thermal instability. Here, a self-formed interfacial protective layer coupled with lattice tuning was constructed for Ni-rich cathodes by simultaneous incorporation of Zr and Al in a one-step calcination. The migration energy between Zr and Al from the surface into the bulk lattice induces dual modifications from the surface into the bulk lattice, which effectively decrease the formation of cation mixing, the degree of anisotropic lattice change, and the generation of microcracks. With the stabilization role provided by the doped Zr-Al ions and protective function endowed by the surface layer, the modified cathode material exhibits significantly enhanced capacity and voltage retention. Specifically, the capacity retention for the modified cathode material reaches 99% after 100 cycles at 1 C and 25 °C in a voltage range of 3.0-4.3 V, which outperformed that for the pristine cathode (70%). The declination values of the average voltage for the modified cathode are only 0.025 and 0.097 V after 100 cycles at 1 C in voltage ranges of 3.0-4.3 and 2.8-4.5 V, respectively, which are much lower than those for the pristine cathode (0.230 and 0.405 V). The synchronous accomplishment of modification from the surface into the bulk lattice for Ni-rich materials with multiple elements in a one-step calcination process would provide some referenced value for the preparation of other cathode materials.

10.
Angew Chem Int Ed Engl ; 59(4): 1491-1495, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31677318

RESUMO

Demands for large-scale energy storage systems have driven the development of layered transition-metal oxide cathodes for room-temperature rechargeable sodium ion batteries (SIBs). Now, an abnormal layered-tunnel heterostructure Na0.44 Co0.1 Mn0.9 O2 cathode material induced by chemical element substitution is reported. By virtue of beneficial synergistic effects, this layered-tunnel electrode shows outstanding electrochemical performance in sodium half-cell system and excellent compatibility with hard carbon anode in sodium full-cell system. The underlying formation process, charge compensation mechanism, phase transition, and sodium-ion storage electrochemistry are clearly articulated and confirmed through combined analyses of in situ high-energy X-ray diffraction and ex situ X-ray absorption spectroscopy as well as operando X-ray diffraction. This crystal structure engineering regulation strategy offers a future outlook into advanced cathode materials for SIBs.

11.
Chinese Journal of Cardiology ; (12): 373-377, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-941119

RESUMO

Objective: To investigate the influencing factors of in-stent restenosis (ISR) following successful stent implantation in patients with ablation-associated severe pulmonary vein stenosis (PVS) who undergo atrial fibrillation ablation. Methods: Data of patients who underwent pulmonary vein angiography to confirm PVS after radiofrequency ablation for atrial fibrillation (AF) and received pulmonary vein stenting at Shanghai Chest Hospital from March 2010 to December 2017 were retrospectively analysed. All patients were followed up for a long period of time (pulmonary vein contract-enhanced CT within 6 to 12 months after operation was performed, and pulmonary angiography was performed if CT indicated stenosis>50%). The incidence of ISR was recorded. According to angiography, the patients were divided into ISR group and non-ISR group. The clinical and intraoperative imaging characteristics and interventional data were compared between the two groups. Logistic regression was used to analyse the influencing factors of ISR. Results: A total of 47 patients ((47.1±12.2) years old) were enrolled in this study, including 28 males(59.6%). There were 19 cases in ISR group and 28 cases in non-ISR group. Compared with the non-ISR group, the ISR group received more pulmonary vein isolation ((2.8±0.9) vs. (1.8±1.3), P=0.02), and the interval between last ablation and stenting was longer ((19.4±9.6) vs. (13.0±12.4), P=0.03). The incidence of ISR in patients with stent diameter≤8 mm was significantly higher than those with stent diameter>8 mm (33.3%(20/60) vs. 8.1%(3/37), P<0.01). Logistic regression analysis found that the number of radiofrequency ablation>1 (OR=2.1, 95%CI 1.3-3.9, P=0.02), and the time from the last ablation to stent placement>12 months (OR=1.5, 95%CI 1.1-2.5, P=0.03), reference diameter of stenosed distal vessel (OR=0.7, 95%CI 0.5-0.9, P=0.04), post procedural minimal luminal diameter (OR=0.4, 95%CI 0.2-0.8, P=0.02) and stent diameter (OR=0.6, 95%CI 0.3-0.9, P=0.03) were independent factors of ISR. Conclusions: The greater number of radiofrequency ablations and the longer time from the last ablation to stent placement increase the risk of ISR. The larger reference diameter of the stenosed distal vessel, stent diameter and post procedural minimal luminal diameter are the protective factors of ISR.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibrilação Atrial , Ablação por Cateter , China , Constrição Patológica , Reestenose Coronária , Veias Pulmonares , Estudos Retrospectivos , Estenose de Veia Pulmonar , Stents , Resultado do Tratamento
12.
Adv Sci (Weinh) ; 6(13): 1801908, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31380176

RESUMO

Spinel-type LiMn2O4 cathode materials commonly suffer from manganese dissolution due to the severe interfacial side reactions especially at elevated temperature. Here, a 3D hollow fusiform LiMn2O4 cathode material is reported with preferentially exposed stable {111} facets and seamless outer structure, which is clearly confirmed by microfocused ion beam scanning electron microscopy, high-resolution transmission electron microscopy as well as scanning transmission electron microscopy with atomic resolution. Owing to the optimal geometrical structure design and the preferentially exposed stable {111} facets, the electrode delivers excellent rate capability (107.6 mAh g-1 at 10 C), remarkable cycling stability (83.3% capacity retention after 1000 cycles at 1 C), and outstanding high-temperature performance. Together with the analyses of electrochemical behaviors, in situ X-ray diffraction at different temperatures, and ex situ X-ray photoelectron spectra, the underlying working mechanism for suppressing manganese dissolution is clearly articulated. These findings could provide significant guidelines for precisely designing highly stable cathode materials for LIBs.

13.
ACS Appl Mater Interfaces ; 11(30): 26938-26945, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31271031

RESUMO

Composite cathodes have attracted great attention due to the integrated advantages of each pure structure. Also, the component ratio deserves a careful modulation to further improve the corresponding electrochemical performance. Mn-based layer-tunnel hybrid composite became a focus in sodium-ion batteries due to the superiority in terms of high performance, low cost, and nontoxicity. In the previous reports, the structure modulation was carried out via changing the synthesis condition, varying the transition-metal-element ratio, and different ion doping. Also, it is still challenging to explore a more feasible method to simplify the adjustment process. Herein, we introduced Mg2+ into Na sites or transition-metal sites in Na0.6MnO2 and first discovered the doping-site-variation-induced structural adjustment phenomenon. Specifically, Mg doping in transition-metal sites could be beneficial for the growth of the P2-type structure, while layer/tunnel component ratio decreased when locating Mg2+ in Na sites. The P2-O2 phase transformations could be effectively suppressed by locating Mg2+ in both sites in high-voltage regions and thus improve the cycling performance. The designed material, Na0.6Mn0.99Mg0.01O2, could attain a decent capacity of 100 mA h g-1 at 1000 mA g-1 and a satisfied retention of 76.6% after 500 cycles. Additionally, ex situ X-ray diffraction analysis experiments verify the excellent structural stability of Mg-substituted samples during charge-discharge processes. Moreover, the Na0.6Mn0.99Mg0.01O2 also displays superior sodium-ion full-cell properties when merged with hard carbon anode. Thus, this research may indicate a proper novel thread for designing high-performance composite electrodes.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-821659

RESUMO

Objective To understand the epidemic status of clonorchiasis sinensis in western region of Jilin Province, so as to provide the evidence for formulating the planning and strategy of prevention and control of the disease. Methods In 2017, the areas where the residents had the customs of eating Sashimi were selected as the research areas in the western region of Jilin Province, and according to the cluster sampling, 25 villages in 25 towns (each village per town) of 5 counties in the region were selected as the investigation points. The basic information of crowd was collected by a questionnaire investigation. The Kato-Katz method was used for etiological examinations. The results were analyzed statistically. Results A total of 4 980 people in the 25 villages were investigated, and 1 220 people were infected with Clonorchis sinensis. The average infection rate was 24.50%. There was a significant difference among different counties (cities, districts) in the infection rate of C. sinensis (P < 0.01), and the infection rate in Daan City was the highest (53.82%). In addition, there were significant differences between/among the gender, nation, age, educational level, and occupation in the infection rate (all P values < 0.01). The infection rate of the male was higher than that of the female, the rate of Han was higher than that of other ethnic groups, the rate of the high age group was higher than that of the low age group, the rate of the college degree group was higher than that of the other educational level groups, the rate of the cadre was higher than that of the other occupation groups, and the rate of the group who had vermifuge before the investigation was lower than that of the group who did not have vermifuge. Conclusions The western region of Jilin Province is still the highincidence area of clonorchiasis sinensis. Therefore, the comprehensive control and prevention measures, such as giving vermifuge and health education, should be strengthened in key population and areas in the future.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-743443

RESUMO

Imaging techniques play a vital role in evaluating myocardial damage in patients with myocardial infarction. Accurate evaluations of postinfarction function and scar can help identify high-risk patients and provide prognosis information, which contributes much to clinical practice. The assessment of myocardial damage mainly includes overall evaluations of ventricular function and remodeling and targeted characterization of myocardial infarction including infarct size, myocardial viability and microvascular obstruction. Echocardiography, cardiac magnetic resonance, CT and nuclear examinations are most common imaging techniques currently. This review is to update evidence on applications of these modalities in evaluation of postinfarction myocardial damage and offer some helps to health workers.

16.
Adv Mater ; : e1803765, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30144167

RESUMO

As one of the most promising cathodes for rechargeable sodium-ion batteries (SIBs), O3-type layered transition metal oxides commonly suffer from inevitably complicated phase transitions and sluggish kinetics. Here, a Na[Li0.05 Ni0.3 Mn0.5 Cu0.1 Mg0.05 ]O2 cathode material with the exposed {010} active facets by multiple-layer oriented stacking nanosheets is presented. Owing to reasonable geometrical structure design and chemical substitution, the electrode delivers outstanding rate performance (71.8 mAh g-1 and 16.9 kW kg-1 at 50C), remarkable cycling stability (91.9% capacity retention after 600 cycles at 5C), and excellent compatibility with hard carbon anode. Based on the combined analyses of cyclic voltammograms, ex situ X-ray absorption spectroscopy, and operando X-ray diffraction, the reaction mechanisms behind the superior electrochemical performance are clearly articulated. Surprisingly, Ni2+ /Ni3+ and Cu2+ /Cu3+ redox couples are simultaneously involved in the charge compensation with a highly reversible O3-P3 phase transition during charge/discharge process and the Na+ storage is governed by a capacitive mechanism via quantitative kinetics analysis. This optimal bifunctional regulation strategy may offer new insights into the rational design of high-performance cathode materials for SIBs.

17.
ACS Appl Mater Interfaces ; 10(33): 27821-27830, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30063329

RESUMO

Nickel-rich layered oxides are regarded as very promising materials as cathodes for lithium-ion batteries because of their environmental benignancy, low cost, and high energy density. However, insufficient cycle performance and poor thermotic characteristics induced by structural degradation at high potentials and elevated temperatures pose challenging hurdles for nickel-rich cathodes. Here, a protective pillaring layer, in which partial Ni2+ ions occupy Li slabs induced by gradient Mn4+, is integrated into the primary particle of LiNi0.815Co0.15Al0.035O2 to stabilize the surface/interfacial structure. With the stable outer surface provided by the enriched Mn4+ gradient concentration and the pillar effect of the NiO-like phase, Mn-incorporated quaternary cathodes show enhanced structural stability and improved Li+ diffusion as well as lithium-storage properties. Compared with the severe capacity fade of a pure layered structure, the cathode with gradient Mn4+ exhibits more stable cycling behavior with a capacity retention of 80.0% after 500 cycles at 5.0 C.

18.
ACS Appl Mater Interfaces ; 10(12): 10147-10156, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29504762

RESUMO

Sodium-ion batteries (SIBs) have been regarded as a promising candidate for large-scale renewable energy storage system. Layered manganese oxide cathode possesses the advantages of high energy density, low cost and natural abundance while suffering from limited cycling life and poor rate capacity. To overcome these weaknesses, layer-tunnel hybrid material was developed and served as the cathode of SIB, which integrated high capacity, superior cycle ability, and rate performance. In the current work, the doping of copper was adopted to suppress the Jahn-Teller effect of Mn3+ and to affect relevant structural parameters. Multifunctions of the Cu2+ doping were carefully investigated. It was found that the structure component ratio is varied with the Cu2+ doping amount. Results demonstrated that Na+/vacancy rearrangement and phase transitions were suppressed during cycling without sacrificing the reversible capacity and enhanced electrochemical performances evidenced with 96 mA h g-1 retained after 250 cycles at 4 C and 85 mA h g-1 at 8 C. Furthermore, ex situ X-ray diffraction has demonstrated high reversibility of the Na0.6Mn0.9Cu0.1O2 cathode during Na+ extraction/insertion processes and superior air stability that results in better storage properties. This study reveals that the Cu2+ doping could be an effective strategy to tune the properties and related performances of Mn-based layer-tunnel hybrid cathode.

19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-695736

RESUMO

Drug-coated balloons (DCB) have emerged as a new application in percutaneous coronary intervention. It is developed to circumvent some of the limitations faced by drug-eluting stents (DES). DES has some limitations, as follows: it could not be implanted in some lesions; bleeding risks are associated with prolonged dual antiplatelet therapy; risks of late and very late stent thrombosis increase. Many clinical trials had confirmed the efficacy and safety of DCB, particularly, the application of DCB in coronary small vessel diseases. This review discussed the basic concept, development, evolution of DCB and some clinical studies associated with the application of DCB in coronary small vessel diseases.

20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-711404

RESUMO

Objective To evaluate the safety of influenza vaccine and 23-valent pneumococcal polysaccharide vaccine (PPV23) immunized alone or in combination in elderly people and to raise the awareness of vaccine safety among the elderly. Methods From October 2014 to September 2015,454 eld-erly people who were over 60 years old and immunized with influenza vaccine and PPV23 alone or in combi-nation were recruited in this study and divided into five groups. Local and systemic reactions occurred within one month after vaccination were recorded. Results (1) Incidences of adverse reactions among all subjects and people vaccinated with influenza vaccine alone,domestic PPV23 alone,imported PPV23 alone,domes-tic PPV23 combined with influenza vaccine and imported PPV23 combined with influenza vaccine were 10.13%,5.35%,11.63 %,9.52%,17.24% and 12.63%,respectively. Local reaction,injection site pain and mild reaction were the common reactions to vaccination. All reactions occurred within seven days and most of them occurred within 30 minutes to one day after vaccination(82.61%). All subjects recovered within seven days and most of them recovered within one day (84.78%). (2) Compared with the people immunized with domestic or imported PPV23 or influenza vaccine alone,those immunized in combination had higher incidences of reactions to vaccination. Among the three single vaccination groups, domestic PPV23 group had the highest incidence of reactions,followed by imported PPV23 and influenza vaccine groups,but no significant difference was found among them(P>0.05). The incidence of responses to influenza vaccine combined with domestic PPV23 was higher than that to influenza vaccine combined with imported PPV23, but no significant difference was found between them (P>0.05). (3) In each group,women,people aged≥70 years or with chronic diseases had a higher incidence of responses to vaccination than men,people aged 60 to 69 years or without chronic diseases,respectively (P>0.05). Conclusion Immunization with influ-enza vaccine and PPV23 alone or in combination is safe and tolerable in elderly people regardless of gender, age,or whether they are suffering from chronic diseases or not. Both domestic and imported PPV23 have the feature of good safety.

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