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1.
Artigo em Inglês | MEDLINE | ID: mdl-32976693

RESUMO

The performance of Li-ion batteries (LIBs) is highly dependent on their interfacial chemistry, which is regulated by electrolytes. Conventional electrolyte typically contains polar solvents to dissociate Li salts. Herein we report a weakly solvating electrolyte (WSE) that consists of a pure non-polar solvent, which leads to a peculiar solvation structure where ion pairs and aggregates prevail under a low salt concentration of 1.0 M. Importantly, WSE forms unique anion-derived interphases on graphite electrodes that exhibit fast-charging and long-term cycling characteristics. First-principles calculations unravel a general principle that the competitive coordination between anions and solvents to Li ions is the origin of different interfacial chemistries. By bridging the gap between solution thermodynamics and interfacial chemistry in batteries, this work opens a brand-new way towards precise electrolyte engineering for energy storage devices with desired properties.

2.
Adv Mater ; 32(37): e2003012, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32761715

RESUMO

The lithium-sulfur (Li-S) battery is regarded as a promising high-energy-density battery system, in which the dissolution-precipitation redox reactions of the S cathode are critical. However, soluble Li polysulfides (LiPSs), as the indispensable intermediates, easily diffuse to the Li anode and react with the Li metal severely, thus depleting the active materials and inducing the rapid failure of the battery, especially under practical conditions. Herein, an organosulfur-containing solid electrolyte interphase (SEI) is tailored for the stabilizaiton of the Li anode in Li-S batteries by employing 3,5-bis(trifluoromethyl)thiophenol as an electrolyte additive. The organosulfur-containing SEI protects the Li anode from the detrimental reactions with LiPSs and decreases its corrosion. Under practical conditions with a high-loading S cathode (4.5 mgS cm-2 ), a low electrolyte/S ratio (5.0 µL mgS -1 ), and an ultrathin Li anode (50 µm), a Li-S battery delivers 82 cycles with an organosulfur-containing SEI in comparison to 42 cycles with a routine SEI. This work provokes the vital insights into the role of the organic components of SEI in the protection of the Li anode in practical Li-S batteries.

3.
ACS Cent Sci ; 6(7): 1095-1104, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32724844

RESUMO

Lithium-sulfur (Li-S) batteries have long been expected to be a promising high-energy-density secondary battery system since their first prototype in the 1960s. During the past decade, great progress has been achieved in promoting the performances of Li-S batteries by addressing the challenges at the laboratory-level model systems. With growing attention paid to the application of Li-S batteries, new challenges at practical cell scales emerge as the bottleneck. In this Outlook, the key parameters for practical Li-S batteries to achieve practical high energy density are emphasized regarding high-sulfur-loading cathodes, lean electrolytes, and limited excess anodes. Subsequently, the key scientific problems are redefined in practical Li-S batteries beyond the previous ones under ideal conditions. Finally, viable strategies are proposed to address the above challenges as future research directions.

4.
Adv Parasitol ; 110: 319-347, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32563330

RESUMO

The analysis of epidemiological data has played an important role for the academic research carried out by the National Institute of Parasitic Diseases, China CDC, since its foundation in 1950s. Those researches, e.g., the temporal-spatial patterns of disease transmission and the identification of risk factors, have contributed significantly to the national parasitic disease control and elimination programmes in China. With the development and application of epidemiological data analysis in the last decade, all research results improve our understanding of parasitic diseases epidemiology and related health issues through the application platform of epidemiological big data and analytical tools. In particular, implementation research on analytical predictions on disease outbreak or epidemic risks have provided references to the scientific guidance on effective preventions and interventions in the parasitic disease elimination in China, such as fliariasis, malaria and schistosomiasis. This review has reflected the function of data accumulation and application of temporospatial tools in parasitic diseases control, and the ways of the NIPD's sustained contributions to the disease control programmes in China.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32426911

RESUMO

Stable operation at elevated temperature is necessary for lithium metal anode. However, Li metal anode generally has poor performance and safety concerns at high temperature (>55 °C) owing to the thermal instability of the electrolyte and solid electrolyte interphase in a routine liquid electrolyte. Herein a Li metal anode working at an elevated temperature (90 °C) is demonstrated in a thermotolerant electrolyte. In a Li|LiFePO4 battery working at 90 °C, the anode undergoes 100 cycles compared with 10 cycles in a practical carbonate electrolyte. During the formation of the solid electrolyte interphase, independent and incomplete decomposition of Li salts and solvents aggravate. Some unstable intermediates emerge at 90 °C, degenerating the uniformity of Li deposition. This work not only demonstrates a working Li metal anode at 90 °C, but also provides fundamental understanding of solid electrolyte interphase and Li deposition at elevated temperature for rechargeable batteries.

6.
Adv Mater ; 32(24): e1908293, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32249530

RESUMO

Safe and high-energy-density rechargeable batteries are increasingly indispensable in the pursuit of a wireless and fossil-free society. Advancements in present battery technologies and the investigation of next-generation batteries highly depend on the ever-deepening fundamental understanding and the rational designs of working electrodes, electrolytes, and interfaces. However, accurately analyzing energy materials and interfaces is severely hindered by their intrinsic limitations of air and electron-beam sensitivity, which restrains the research of energy materials in a low-efficiency trial-and-error paradigm. The emergence of cryogenic electron microscopy (cryo-EM) has enabled the nondestructive characterization of air- and electron-beam sensitive energy materials in the microscale and nanoscale, and even at atomic resolutions, affording closer insights into the primary chemistry and physics of working batteries. Herein, the development of cryo-EM and the applications in detecting energy materials are reviewed and analyzed from its overwhelming advantages in disclosing the underlying mystery of energy materials. Critical sample preparation methods as the precondition for cryo-EM are compared, which strongly affect the characterization accuracy. Furthermore, new developments in the analysis of energy materials, especially bulk electrodes and interfaces in lithium metal batteries, are presented according to different functions of cryo-EM. Finally, future directions of cryo-EM for analyzing energy materials are prospected.

7.
Angew Chem Int Ed Engl ; 59(8): 3252-3257, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31756011

RESUMO

High-energy-density Li metal batteries suffer from a short lifespan under practical conditions, such as limited lithium, high loading cathode, and lean electrolytes, owing to the absence of appropriate solid electrolyte interphase (SEI). Herein, a sustainable SEI was designed rationally by combining fluorinated co-solvents with sustained-release additives for practical challenges. The intrinsic uniformity of SEI and the constant supplements of building blocks of SEI jointly afford to sustainable SEI. Specific spatial distributions and abundant heterogeneous grain boundaries of LiF, LiNx Oy , and Li2 O effectively regulate uniformity of Li deposition. In a Li metal battery with an ultrathin Li anode (33 µm), a high-loading LiNi0.5 Co0.2 Mn0.3 O2 cathode (4.4 mAh cm-2 ), and lean electrolytes (6.1 g Ah-1 ), 83 % of initial capacity retains after 150 cycles. A pouch cell (3.5 Ah) demonstrated a specific energy of 340 Wh kg-1 for 60 cycles with lean electrolytes (2.3 g Ah-1 ).

8.
Sci Rep ; 9(1): 19766, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31875029

RESUMO

Currently, little is known regarding the value of quantitative parameters derived from the intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) with integrated slice-specific shimming (iShim) sequence in detecting old myocardial infarction and myocardial fibrosis. This study was to investigate the value of IVIM-MRI with iShim sequence in diagnosing old myocardial infarction and fibrosis. Thirty-five patients with both old myocardial infarction and myocardial fibrosis and 12 healthy volunteers were prospectively enrolled to undergo cardiac diffusion-weighted imaging (DWI) using seven b-values (0, 20, 60, 80, 120, 200 and 600 s/mm2). The iShim sequence was used for IVIM data acquisition, and the diffusion parameters, D, D* and f values for IVIM, and conventional apparent diffusion coefficient (ADC) were evaluated on the anterior, posterior and lateral walls of the ventricular septum using the short axis of the heart. Significant differences were found in the D, D* and f values between healthy subjects and patients with old myocardial infarction and myocardial fibrosis (P = 0.000), with the median value of the D and f significantly smaller in the myocardial infarction and fibrosis than in the normal control but the median value of D* significantly greater in the myocardial infarction and fibrosis than in the normal control. In the receiver operating curve analysis, the areas under the curve were 0.939, 0.988 and 0.959 for the D, D* and f values, respectively. The sensitivities and specificities were 84.6% and 94.4% for D, 88.9% and 84.6% for D* and 100% and 93.1% for the f values, respectively. In conclusion, the IVIM-derived parameters (D, D* and f) obtained using the iShim DWI technique showed high capacity in diagnosing old myocardial infarction and myocardial fibrosis by providing diffusion and perfusion information, which may have great importance in future clinical practice.


Assuntos
Imagem de Difusão por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio , Adulto , Idoso , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
9.
World J Clin Cases ; 7(17): 2450-2462, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31559281

RESUMO

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) is widely accepted as an alternative to surgery for management of complications of portal hypertension. TIPS has been used to treat portal vein thrombosis (PVT) in many centers since the 1990s. Although TIPS has good therapeutic effects on the formation of PVT, the effect of PVT on TIPS stenting has rarely been reported. Patients with splenectomy and pericardial devascu-larization have a high incidence of PVT, which can markedly affect TIPS stent patency and increase the risk of recurrent symptoms associated with shunt stenosis or occlusion. AIM: To investigate the incidence of PVT after splenectomy and its influence on the patency rate of TIPS in patients with cirrhosis and portal hypertension. METHODS: Four hundred and eighty-six patients with portal hypertension for refractory ascites and/or variceal bleeding who required TIPS placement between January 2010 and January 2016 were included in this retrospective analysis. Patients without prior splenectomy were defined as group A (n = 289) and those with prior splenectomy as group B (n = 197). The incidence of PVT before TIPS was compared between the two groups. After TIPS placement, primary patency rate was compared using Kaplan-Meier analysis at 3, 6, 9 and 12 mo, and 2 and 3 years. The clinical outcomes were analyzed. RESULTS: Before TIPS procedure, the incidence of PVT in group A was lower than in group B (P = 0.003), and TIPS technical success rate in group A was higher than in group B (P = 0.016). The primary patency rate in group A tended to be higher than in group B at 3, 6, 9 and 12 mo, 2 years and 3 years (P = 0.006, P = 0.011, P = 0.023, P = 0.032, P = 0.037 and P = 0.028, respectively). Recurrence of bleeding and ascites rate in group A was lower than in group B at 3 mo (P ≤ 0.001 and P = 0.001), 6 mo (P = 0.003 and P = 0.005), 9 mo (P = 0.005 and P = 0.012), 12 mo (P = 0.008 and P = 0.024), 2 years (P = 0.011 and P = 0.018) and 3 years (P = 0.016 and P = 0.017), respectively. During 3-years follow-up, the 1-, 2- and 3-year survival rate in group A were higher than in group B (P = 0.008, P = 0.021, P = 0.018, respectively), but there was no difference of the incidence of hepatic encephalopathy (P = 0.527). CONCLUSION: Patients with prior splenectomy have a high incidence of PVT, which potentially increases the risk of recurrent symptoms associated with shunt stenosis or occlusion.

10.
Adv Mater ; 31(37): e1902785, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31379042

RESUMO

Lithium (Li) metal is regarded as a "Holy Grail" electrode for next-generation high-energy-density batteries. However, the electrochemical behavior of the Li anode under a practical working state is poorly understood, leading to a gap in the design strategy and the aim of efficient Li anodes. The electrochemical diagram to reveal failure mechanisms of ultrathin Li in pouch cells is demonstrated. The working mode of the Li metal anode ranging from 1.0 mA cm-2 /1.0 mAh cm-2 (28.0 mA/28.0 mAh) to 10.0 mA cm-2 /10.0 mAh cm-2 (280.0 mA/280.0 mAh) is investigated and divided into three categories: polarization, transition, and short-circuit zones. Powdering and the induced polarization are the main reasons for the failure of the Li electrode at small current density and capacity, while short-circuit occurs with the damage of the separator leading to safety concerns being dominant at large current and capacity. The electrochemical diagram is attributed from the distinctive plating/stripping behaviors of Li metal, accompanied by dendrites thickening and/or lengthening, and heterogeneous distribution of dendrites. A clear understanding in the electrochemical diagram of ultrathin Li is the primary step to rationally design an effective Li electrode and render a Li metal battery with high energy density, long lifespan, and enhanced safety.

11.
J Am Chem Soc ; 141(23): 9422-9429, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31117672

RESUMO

The stability of a battery is strongly dependent on the feature of solid electrolyte interphase (SEI). The electrical double layer forms prior to the formation of SEI at the interface between the Li metal anode and the electrolyte. The fundamental understanding on the regulation of the SEI structure and stability on Li surface through the structure of the electrical double layer is highly necessary for safe batteries. Herein, the interfacial chemistry of the SEI is correlated with the initial Li surface adsorption electrical double layer at the nanoscale through theoretical and experimental analysis. Under the premise of the constant solvation sheath structure of Li+ in bulk electrolyte, a trace amount of lithium nitrate (LiNO3) and copper fluoride (CuF2) were employed in electrolytes to build robust electric double layer structures on a Li metal surface. The distinct results were achieved with the initial competitive adsorption of bis(fluorosulfonyl)imide ion (FSI-), fluoride ion (F-), and nitrate ion (NO3-) in the inner Helmholtz plane. As a result, Cu-NO3- complexes are preferentially adsorbed and reduced to form the SEI. The modified Li metal electrode can achieve an average Coulombic efficiency of 99.5% over 500 cycles, enabling a long lifespan and high capacity retention of practical rechargeable batteries. The as-proposed mechanism bridges the gap between Li+ solvation and the adsorption about the electrode interface formation in a working battery.

12.
Adv Mater ; 31(19): e1808392, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30907487

RESUMO

The lithium (Li) metal anode is confronted by severe interfacial issues that strongly hinder its practical deployment. The unstable interfaces directly induce unfavorable low cycling efficiency, dendritic Li deposition, and even strong safety concerns. An advanced artificial protective layer with single-ion pathways holds great promise for enabling a spatially homogeneous ionic and electric field distribution over Li metal surface, therefore well protecting the Li metal anode during long-term working conditions. Herein, a robust dual-phase artificial interface is constructed, where not only the single-ion-conducting nature, but also high mechanical rigidity and considerable deformability can be fulfilled simultaneously by the rational integration of a garnet Al-doped Li6.75 La3 Zr1.75 Ta0.25 O12 -based bottom layer and a lithiated Nafion top layer. The as-constructed artificial solid electrolyte interphase is demonstrated to significantly stabilize the repeated cell charging/discharging process via regulating a facile Li-ion transport and a compact Li plating behavior, hence contributing to a higher coulombic efficiency and a considerably enhanced cyclability of lithium metal batteries. This work highlights the significance of rational manipulation of the interfacial properties of a working Li metal anode and affords fresh insights into achieving dendrite-free Li deposition behavior in a working battery.

13.
Folia Neuropathol ; 57(4): 357-365, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32337949

RESUMO

The purpose of this study was to evaluate whether FGD5-AS1 participates in oxygen-glucose deprivation and simulated reperfusion (OGD/R)-induced neurons injury and the detailed mechanism. An OGD/R model was established using the primary cortical neuron isolated from the brains of Sprague-Dawley rats. qRT-PCR and western blot were performed to de-tect the RNA and protein expression levels, respectively. Cell counting kit 8 (CCK8) and flow cytometry assays were used to evaluate the proliferation and apoptosis of neurons. The luciferase reporter assay was used to verify the interaction between lncRNA FGD5-AS1 and miRNA-223. We found that the expression of FGD5-AS1 is decreased in neurons suffering from OGD/R. Up-regulation of FGD5-AS1 could recover proliferation and inhibit apoptosis of OGD/R-injured neurons. In addition, the interaction between FGD5-AS1 and miRNA-223 were verified. The expression of miRNA-223 was negatively correlated with the level of FGD5-AS1. In turn, the expression of insulin-like growth factor-1 receptor (IGFIR, a target gene of miR-223) was positively associated with the level of FGD5-AS1. Simultaneously down-regulating miR-223 and over-expressing FGD5-AS1 as well as IGF1R exhibited an additional effect of extenuating OGD/R damage i.e. increasing neuron proliferation and reducing neuron apoptosis. In conclusion, our findings indicated that FGD5-AS1 may protect the neuron against OGD/R injury via acting as a ceRNA for miR-223 to mediate IGF1R expression, which contributes to a deeper understanding of ischemic stroke and provide a promising therapeutic target for this disease.


Assuntos
MicroRNAs/genética , Neurônios/metabolismo , Oxigênio/metabolismo , RNA Longo não Codificante/genética , Acidente Vascular Cerebral/genética , Animais , Apoptose/genética , Glucose/genética , Glucose/metabolismo , Ratos Sprague-Dawley , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Acidente Vascular Cerebral/metabolismo
14.
Sci Adv ; 4(11): eaat3446, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30430133

RESUMO

Lithium (Li) metal anodes have attracted considerable interest due to their ultrahigh theoretical gravimetric capacity and very low redox potential. However, the issues of nonuniform lithium deposits (dendritic Li) during cycling are hindering the practical applications of Li metal batteries. Herein, we propose a concept of ion redistributors to eliminate dendrites by redistributing Li ions with Al-doped Li6.75La3Zr1.75Ta0.25O12 (LLZTO) coated polypropylene (PP) separators. The LLZTO with three-dimensional ion channels can act as a redistributor to regulate the movement of Li ions, delivering a uniform Li ion distribution for dendrite-free Li deposition. The standard deviation of ion concentration beneath the LLZTO composite separator is 13 times less than that beneath the routine PP separator. A Coulombic efficiency larger than 98% over 450 cycles is achieved in a Li | Cu cell with the LLZTO-coated separator. This approach enables a high specific capacity of 140 mAh g-1 for LiFePO4 | Li pouch cells and prolonged cycle life span of 800 hours for Li | Li pouch cells, respectively. This strategy is facile and efficient in regulating Li-ion deposition by separator modifications and is a universal method to protect alkali metal anodes in rechargeable batteries.

15.
Medicine (Baltimore) ; 97(36): e11902, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30200075

RESUMO

This study aims to explore the possibility to apply intravoxel incoherent motion-magnetic resonance imaging (IVIM-MRI) in cardiac imaging.Multi-b-value diffusion-weighted imaging (DWI) sequence scanning was performed on 12 healthy volunteers. A double exponential model was adopted, and the b-value sequence was 0, 20, 60, 80, 120, 200, and 600 second/mm. The D-value, D*-value, and f-value of the anterior posterior and lateral walls of the ventricular septum were respectively measured on the short axis section of the heart, the parameters of the myocardium in different blood supply areas in each segment were recorded, and the measured data of these different segments were compared using analysis of variance.Among these 12 healthy volunteers, the D-value, D*-value, and f-value of these 72 segments were not exactly equal, the D-values of the myocardium in the 5th and 11th segment were lower than those in the 2nd, 3rd, 8th, and 9th segments, and the pairwise differences were statistically significant (P < .001). Furthermore, the difference in D-value between the 5th and 11th segments was not statistically significant (P = 1.000). The D*-value and f-value of the myocardium in the 5th and 11th segment were higher than those in the 2nd, 3rd, 8th, and 9th segments, and the pairwise differences were statistically significant (P < .001). Furthermore, the differences in D*-value and f-value between the 5th and 11th segments was not statistically significant (P = .214, .787).The intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) technique can quantitatively reflect the diffusion and blood perfusion status of the myocardium.


Assuntos
Técnicas de Imagem Cardíaca/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Coração/diagnóstico por imagem , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Adulto Jovem
16.
Angew Chem Int Ed Engl ; 57(43): 14055-14059, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30094909

RESUMO

The lithium metal anode is regarded as a promising candidate in next-generation energy storage devices. Lithium nitrate (LiNO3 ) is widely applied as an effective additive in ether electrolyte to increase the interfacial stability in batteries containing lithium metal anodes. However, because of its poor solubility LiNO3 is rarely utilized in the high-voltage window provided by carbonate electrolyte. Dissolution of LiNO3 in carbonate electrolyte is realized through an effective solvation regulation strategy. LiNO3 can be directly dissolved in an ethylene carbonate/diethyl carbonate electrolyte mixture by adding trace amounts of copper fluoride as a dissolution promoter. LiNO3 protects the Li metal anode in a working high-voltage Li metal battery. When a LiNi0.80 Co0.15 Al0.05 O2 cathode is paired with a Li metal anode, an extraordinary capacity retention of 53 % is achieved after 300 cycles (13 % after 200 cycles for LiNO3 -free electrolyte) and a very high average Coulombic efficiency above 99.5 % is achieved at 0.5 C. The solvation chemistry of LiNO3 -containing carbonate electrolyte may sustain high-voltage Li metal anodes operating in corrosive carbonate electrolytes.

17.
J Antibiot (Tokyo) ; 71(8): 731-740, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29691485

RESUMO

Biotransformation of wortmannilactone F (3) using the marine-derived fungus DL1103 generated wortmannilactone M (1), a novel analog of wortmannilactone, which was a reduction product of 3 at the C-3 carbonyl group. The in vitro inhibitory activities of 10 wortmannilactones, including 1, against electron transport enzymes indicated that all the wortmannilactones were selective inhibitors of NADH-fumarate reductase and NADH-rhodoquinone reductase. The structure-activity relationship analysis showed that the relative configuration of C1" and C5", the positions of double bonds, the oxygen atoms in the dihydropyran moiety, and the keto-carbonyl group in the oxabicyclo-[2.2.1]-heptane moiety were important to the inhibitory activity of wortmannilactones. In vivo studies indicated that 3 significantly decreased the number and size of adult worms in Trichinella spiralis-infected mice in a dose-dependent manner. Notable changes in the cuticle and microvilli of T. spiralis were also observed. Our data provided useful information in the research and development of polyketides with dihydropyran and oxabicyclo [2.2.1] heptane moieties as antihelminthics.


Assuntos
Anti-Helmínticos/farmacologia , Complexo de Proteínas da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Macrolídeos/farmacologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Quinona Redutases/antagonistas & inibidores , Trichinella spiralis/efeitos dos fármacos , Triquinelose/tratamento farmacológico , Animais , Modelos Animais de Doenças , Transporte de Elétrons/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Relação Estrutura-Atividade
18.
Adv Mater ; 30(25): e1707629, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29676037

RESUMO

Lithium metal batteries (such as lithium-sulfur, lithium-air, solid state batteries with lithium metal anode) are highly considered as promising candidates for next-generation energy storage systems. However, the unstable interfaces between lithium anode and electrolyte definitely induce the undesired and uncontrollable growth of lithium dendrites, which results in the short-circuit and thermal runaway of the rechargeable batteries. Herein, a dual-layered film is built on a Li metal anode by the immersion of lithium plates into the fluoroethylene carbonate solvent. The ionic conductive film exhibits a compact dual-layered feature with organic components (ROCO2 Li and ROLi) on the top and abundant inorganic components (Li2 CO3 and LiF) in the bottom. The dual-layered interface can protect the Li metal anode from the corrosion of electrolytes and regulate the uniform deposition of Li to achieve a dendrite-free Li metal anode. This work demonstrates the concept of rational construction of dual-layered structured interfaces for safe rechargeable batteries through facile surface modification of Li metal anodes. This not only is critically helpful to comprehensively understand the functional mechanism of fluoroethylene carbonate but also affords a facile and efficient method to protect Li metal anodes.

19.
Folia Neuropathol ; 56(1): 49-57, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29663740

RESUMO

Cerebral ischemia injury seriously endangers human health and its molecular mechanism is still not fully understood. microRNA-223 (miR-223) has been reported to be involved in many physiological functions but the specific role of miRNA-223 in ischemic neuronal injury is still unclear. An oxygen-glucose deprivation and simulated reperfusion (OGD/R) model was constructed here to investigate the possible role miR-223 played in ischemic neuronal injury. The expression of miRNA-223 in the OGD/R model and its effect on cell proliferation were studied by qPCR and CCK8 assay. We observed that miR-223 was significantly over-expressed after OGD/R treatment and it suppressed significantly cortical neurons proliferation. To further study the mechanism involved, we predicted and examined the potential targets of miR-223 by targetscan, qPCR, western blot and luciferase reporter assay. We found that the expression level of type 1 insulin-like growth factor receptor (IGF1R) was negatively associated with the level of miR-223. Furthermore, the relative luciferase activity of pmirGLO-WT was inhibited obviously, while no significant change was observed in the pmirGLO-Mut group, indicating that miR-223 could bind to IGF1R. Similar cell proliferation suppression caused by miR-223 antagomir was observed when IGF1R was silenced. On the contrary, when cortical neurons were co-treated with miR-223 agomir and the cDNA of IGF1R which did not contain 3'- untranslated region, the inhibition caused by miR-223 disappeared. Our results suggested that miR-223 may suppress proliferation of cortical neurons that were treated with OGD/R via inhibiting IGF1R expression.


Assuntos
Isquemia Encefálica/metabolismo , MicroRNAs/metabolismo , Neurônios/metabolismo , Receptores de Somatomedina/metabolismo , Animais , Regulação da Expressão Gênica/fisiologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Acidente Vascular Cerebral/metabolismo
20.
Angew Chem Int Ed Engl ; 57(19): 5301-5305, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29465827

RESUMO

Safe and rechargeable lithium metal batteries have been difficult to achieve because of the formation of lithium dendrites. Herein an emerging electrolyte based on a simple solvation strategy is proposed for highly stable lithium metal anodes in both coin and pouch cells. Fluoroethylene carbonate (FEC) and lithium nitrate (LiNO3 ) were concurrently introduced into an electrolyte, thus altering the solvation sheath of lithium ions, and forming a uniform solid electrolyte interphase (SEI), with an abundance of LiF and LiNx Oy on a working lithium metal anode with dendrite-free lithium deposition. Ultrahigh Coulombic efficiency (99.96 %) and long lifespans (1000 cycles) were achieved when the FEC/LiNO3 electrolyte was applied in working batteries. The solvation chemistry of electrolyte was further explored by molecular dynamics simulations and first-principles calculations. This work provides insight into understanding the critical role of the solvation of lithium ions in forming the SEI and delivering an effective route to optimize electrolytes for safe lithium metal batteries.

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