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1.
J Am Chem Soc ; 146(21): 14754-14764, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38754363

RESUMEN

Lithium-sulfur (Li-S) batteries are highly considered as next-generation energy storage techniques. Weakly solvating electrolyte with low lithium polysulfide (LiPS) solvating power promises Li anode protection and improved cycling stability. However, the cathodic LiPS kinetics is inevitably deteriorated, resulting in severe cathodic polarization and limited energy density. Herein, the LiPS kinetic degradation mechanism in weakly solvating electrolytes is disclosed to construct high-energy-density Li-S batteries. Activation polarization instead of concentration or ohmic polarization is identified as the dominant kinetic limitation, which originates from higher charge-transfer activation energy and a changed rate-determining step. To solve the kinetic issue, a titanium nitride (TiN) electrocatalyst is introduced and corresponding Li-S batteries exhibit reduced polarization, prolonged cycling lifespan, and high actual energy density of 381 Wh kg-1 in 2.5 Ah-level pouch cells. This work clarifies the LiPS reaction mechanism in protective weakly solvating electrolytes and highlights the electrocatalytic regulation strategy toward high-energy-density and long-cycling Li-S batteries.

2.
Chemistry ; 30(20): e202400045, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38298110

RESUMEN

Cinnamic ester is a common and abundant chemical substance, which can be extracted from natural plants. Compared with traditional esters, cinnamic ester contains α,ß-unsaturated carbonyl structure with multiple reactive sites, resulting in more abundant reactivities and chemical structures. Here, a versatile polymerization-induced emission (PIE) is successfully demonstrated through Barbier polymerization of cinnamic ester. Attributed to its abundant reactivities of α,ß-unsaturated carbonyl structure, Barbier polymerization of cinnamic esters with different organodihalides gives polyalcohol and polyketone via 1,2-addition and 1,4-addition, respectively, which is also confirmed by small molecular model reactions. Meanwhile, these organodihalides dependant polyalcohol and polyketone exhibit different non-traditional intrinsic luminescence (NTIL) from aggregation-induced emission (AIE) type to aggregation-caused quenching (ACQ) type, where novel PIE luminogens (PIEgens) are revealed. Further potential applications in explosive detection are carried out, where it achieves TNT detection sensitivity at ppm level in solution and ng level on the test paper. This work therefore expands the structure and functionality libraries of monomer, polymer and NTIL, which might cause inspirations to different fields including polymer chemistry, NTIL, AIE and PIE.

3.
Macromol Rapid Commun ; 45(11): e2400045, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38365211

RESUMEN

Non-traditional intrinsic luminescent (NTIL) polymer is an emerging field, and its color-tunable modification is highly desirable but still rarely investigated. Here, a click chemistry approach for the color-tunable modifications of NTIL polymers by introducing clickable polymerization-induced emission luminogen (PIEgen), is demonstrated. Through Cu-catalyzed azide-alkyne cycloaddition click chemistry, a series of PIEgens is successful prepared, which is further polymerized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Interestingly, after clickable modification, these monomers are nonemissive in both solution and aggregation states; while, the corresponding polymers exhibit intriguing aggregation-induced emission (AIE) characteristics, confirming their PIEgen characteristics. By varying alkynyl substitutions, color-tunable NTIL polymers are achieved with emission wavelength varying from 448 to 498 nm, revealing a series of PIEgens and verifying the importance of modification of NTIL polymers. Further luminescence energy transfer application is carried out as well. This work therefore designs a series of clickable PIEgens and opens a new avenue for the modification of NTIL polymers via click chemistry, which may cause inspirations to the research fields including luminescent polymer, NTIL, click chemistry, AIE and modification.


Asunto(s)
Química Clic , Color , Luminiscencia , Polimerizacion , Polímeros , Polímeros/química , Polímeros/síntesis química , Estructura Molecular , Catálisis , Sustancias Luminiscentes/química , Sustancias Luminiscentes/síntesis química , Azidas/química , Alquinos/química
4.
Int J Mol Sci ; 25(4)2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38396878

RESUMEN

Porcine epidemic diarrhoea virus (PEDV) is a coronavirus that can cause severe watery diarrhoea in piglets, with high morbidity and mortality rates, seriously hindering the healthy development of the global swine industry. In this study, we isolated a strain of PEDV from Tibetan pigs and named it CH/GS/2022. Subsequently, we screened the apoptosis signals of PEDV-infected IPEC-J2 cells and studied the correlation between apoptosis signals and cell apoptosis. The results showed that different infections of PEDV induced different degrees of apoptosis in cells, and PEDV-induced cell apoptosis was dose-dependent. We then detected the expression of the p53, p38, JNK, Bax, and Bcl-2 genes in the apoptosis signal pathway. The results showed that 24 h after PEDV infection, the expression of the p53, p38, JNK, and Bax genes in IPEC-J2 cells increased significantly, while the expression of the Bcl-2 gene decreased significantly (p < 0.05). Subsequently, we used Western blot to detect the protein levels of these five genes, and the results showed that PEDV infection upregulated the expression of p53, p38, JNK, and Bax proteins (p < 0.05) while downregulating the expression of Bcl-2 protein (p < 0.05). Thus, it was initially inferred that PEDV infection could regulate cell apoptosis by activating the p53, p38, and JNK signalling pathways. Finally, we further investigated the apoptosis of the cells through the use of inhibitors. The results indicated that the p53 inhibitor Pifithrin-α has a significant inhibitory effect on the expression of the p53 protein after PEDV infection and can reverse the expression levels of Bax and Bcl-2 proteins. This suggested that p53 is involved in PEDV-induced cell apoptosis. Similarly, the p38 MAPK inhibitor SB203580 has an inhibitory effect on the expression of the p38 protein and can reverse the expression levels of Bax and Bcl-2 proteins. This suggested that p38 is also involved in PEDV-induced cell apoptosis. On the other hand, the JNK inhibitor SP600125 has no inhibitory effect on the expression of the JNK protein after PEDV infection, but the expression levels of Bax and Bcl-2 proteins have changed. Furthermore, it is noteworthy that SP600125 can inhibit the activity of apoptotic proteins but not their levels, resulting in reduced cell apoptosis. These preliminary results indicated that JNK may be involved in PEDV-induced IPEC-J2 cell apoptosis.


Asunto(s)
Antracenos , Virus de la Diarrea Epidémica Porcina , Animales , Porcinos , Línea Celular , Virus de la Diarrea Epidémica Porcina/fisiología , Proteína X Asociada a bcl-2/genética , Proteína p53 Supresora de Tumor/genética , Tibet
5.
J Am Chem Soc ; 145(30): 16449-16457, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37427442

RESUMEN

Lithium-sulfur (Li-S) batteries afford great promise on achieving practical high energy density beyond lithium-ion batteries. Lean-electrolyte conditions constitute the prerequisite for achieving high-energy-density Li-S batteries but inevitably deteriorates battery performances, especially the sulfur cathode kinetics. Herein, the polarizations of the sulfur cathode are systematically decoupled to identify the key kinetic limiting factor in lean-electrolyte Li-S batteries. Concretely, an electrochemical impedance spectroscopy combined galvanostatic intermittent titration technique method is developed to decouple the cathodic polarizations into activation, concentration, and ohmic parts. Therein, activation polarization during lithium sulfide nucleation emerges as the dominant polarization as the electrolyte-to-sulfur ratio (E/S ratio) decreases, and the sluggish interfacial charge transfer kinetics is identified as the main reason for degraded cell performances under lean-electrolyte conditions. Accordingly, a lithium bis(fluorosulfonyl)imide electrolyte is proposed to decrease activation polarization, and Li-S batteries adopting this electrolyte provide a discharge capacity of 985 mAh g-1 under a low E/S ratio of 4 µL mg-1 at 0.2 C. This work identifies the key kinetic limiting factor of lean-electrolyte Li-S batteries and provides guidance on designing rational promotion strategies to achieve advanced Li-S batteries.

6.
J Am Chem Soc ; 145(50): 27531-27538, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38054906

RESUMEN

Single-atom catalysts exhibit promising electrocatalytic activity, a trait that can be further enhanced through the introduction of heteroatom doping within the carbon skeleton. Nonetheless, the intricate relationship between the doping positions and activity remains incompletely elucidated. This contribution sheds light on an inductive effect of single-atom sites, showcasing that the activity of the oxygen reduction reaction (ORR) can be augmented by reducing the spatial gap between the doped heteroatom and the single-atom sites. Drawing inspiration from this inductive effect, we propose a synthesis strategy involving ligand modification aimed at precisely adjusting the distance between dopants and single-atom sites. This precise synthesis leads to optimized electrocatalytic activity for the ORR. The resultant electrocatalyst, characterized by Fe-N3P1 single-atom sites, demonstrates remarkable ORR activity, thus exhibiting great potential in zinc-air batteries and fuel cells.

7.
Microb Pathog ; 181: 106185, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37269880

RESUMEN

Porcine Epidemic Diarrhoea (PED) is an acute, extremely infectious intestinal disease of pigs caused by the Porcine Epidemic Diarrhoea Virus (PEDV). The virus can affect pigs of all breeds and age groups and shows varying degrees of symptoms, with piglets, in particular, being infected with mortality rates of up to 100%. PEDV was first identified in China in the 1980s and in October 2010 a large-scale PED outbreak caused by a variant of PEDV occurred in China, resulting in huge economic losses. Initially, vaccination can effectively prevent the classical strain, but since December 2010, the PEDV variant has caused "persistent diarrhoea" with severe vomiting, watery diarrhoea, and high morbidity and mortality in newborn piglets as the dominant clinical features, with a significant increase in morbidity and mortality. This indicates that PEDV strains have mutated during evolution and that traditional vaccines no longer provide effective cross-immune protection, so it is necessary to optimize immunization programs and find effective treatments through epidemiological surveys of PEDV to reduce the economic losses caused by infections with mutated strains. This article reviews the progress of research on the aetiology, epidemiological characteristics, genotyping, pathogenesis, transmission routes, and comprehensive control of PEDV infection in China.


Asunto(s)
Infecciones por Coronavirus , Disentería , Virus de la Diarrea Epidémica Porcina , Enfermedades de los Porcinos , Animales , Porcinos , Virus de la Diarrea Epidémica Porcina/genética , Genotipo , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/veterinaria , Diarrea , China/epidemiología , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/prevención & control
8.
Curr Heart Fail Rep ; 20(1): 1-11, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36479675

RESUMEN

PURPOSE OF REVIEW: The purpose of this review was to synthesize the evidence on non-traditional biomarkers from proteomic and metabolomic studies that may distinguish heart failure (HF) with preserved ejection fraction (HFpEF) from heart failure with reduced ejection fraction (HFrEF) and non-HF. RECENT FINDINGS: Understanding the pathophysiology of HFpEF continues to be challenging. A number of inflammatory and metabolic biomarkers that have recently been suggested to be involved include C-reactive protein (CRP), interleukin-6 (IL-6), trimethylamine-N-oxide (TMAO), syndecan-1 (SDC-1), nitric oxide (NO), and tumor necrosis factor receptor-1 (TNFR-1). A systematic search was conducted using Medline, EMBASE, and Web of Science with search terms such as "HFpEF," "metabolomics," and "proteomics," and a meta-analysis was conducted. The results demonstrate significantly higher levels of TMAO, CRP, SDC-1, and IL-6 in HFpEF compared to controls without HF and significantly higher levels of TMAO and CRP in HFrEF compared to controls. The results further suggest that HFpEF might be distinguishable from HFrEF based on higher levels of IL-6 and lower levels of SDC-1 and NO. These data may reflect pathophysiological differences between HFpEF and HFrEF.


Asunto(s)
Proteína C-Reactiva , Insuficiencia Cardíaca , Humanos , Biomarcadores/metabolismo , Proteína C-Reactiva/metabolismo , Interleucina-6 , Péptido Natriurético Encefálico/metabolismo , Óxido Nítrico , Pronóstico , Proteómica , Volumen Sistólico/fisiología , Sindecano-1
9.
J Cutan Med Surg ; 27(2): 157-164, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36880965

RESUMEN

Atopic dermatitis (AD) is associated with various quality of life concerns including poor sleep. Sleep impairments in children with AD are associated with increased risk of short stature, metabolic syndrome, mental illness and neurocognitive dysfunction. Although the association between AD and sleep disturbance is well established, the specific types of sleep disturbance in pediatric AD patients and their underlying mechanisms are not fully understood. A scoping literature review was performed to characterize and summarize the types of sleep disturbance in children (less than 18 years of age) with AD. 31 papers met inclusion criteria and extracted data were analyzed in an iterative manner. Two types of sleep disturbances were found to be more prevalent in pediatric AD patients in comparison to controls. One category was related to loss of sleep (increased frequency or duration of awakenings, increased sleep fragmentation, delayed sleep onset, decreased total sleep duration, and decreased sleep efficiency). Another category was associated with unusual behaviors during sleep (restlessness/limb movement/scratching, sleep-disordered breathing including obstructive sleep apnea and snoring, nightmares, nocturnal enuresis and nocturnal hyperhidrosis). Some mechanisms underlying these sleep disturbances include pruritus and induced scratching and increased proinflammatory markers induced by sleep loss. Sleep disturbance appears to be associated with AD. We recommend clinicians to consider interventions that may reduce sleep disturbances in children with AD. Further investigation of these sleep disturbances is needed to elucidate pathophysiology, develop additional treatments, and reduce negative impacts on the health outcomes and quality of life in pediatric AD patients.


Asunto(s)
Dermatitis Atópica , Trastornos del Sueño-Vigilia , Niño , Humanos , Dermatitis Atópica/complicaciones , Dermatitis Atópica/epidemiología , Calidad de Vida , Prurito/etiología , Sueño , Trastornos del Sueño-Vigilia/etiología , Trastornos del Sueño-Vigilia/complicaciones
10.
Environ Geochem Health ; 45(11): 8187-8202, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37552412

RESUMEN

We aimed to characterize the association between air pollutants exposure and periodontal diseases outpatient visits and to explore the interactions between ambient air pollutants and meteorological factors. The outpatient visits data of several large stomatological and general hospitals in Hefei during 2015-2020 were collected to explore the relationship between daily air pollutants exposure and periodontal diseases by combining Poisson's generalized linear model (GLMs) and distributed lag nonlinear model (DLNMs). Subgroup analysis was performed to identify the vulnerability of different populations to air pollutants exposure. The interaction between air pollutants and meteorological factors was verified in both multiplicative and additive interaction models. An interquartile range (IQR) increased in nitrogen dioxide (NO2) concentration was associated with the greatest lag-specific relative risk (RR) of gingivitis at lag 3 days (RR = 1.087, 95% CI 1.008-1.173). Fine particulate matter (PM2.5) exposure also increased the risk of periodontitis at the day of exposure (RR = 1.049, 95% CI 1.004-1.096). Elderly patients with gingivitis and periodontitis were both vulnerable to PM2.5 exposure. The interaction analyses showed that exposure to high levels of NO2 at low temperatures was related to an increased risk of gingivitis, while exposure to high levels of NO2 and PM2.5 may also increase the risk of gingivitis and periodontitis in the high-humidity environment, respectively. This study supported that NO2 and PM2.5 exposure increased the risk of gingivitis and periodontitis outpatient visits, respectively. Besides, the adverse effects of air pollutants exposure on periodontal diseases may vary depending on ambient temperature and humidity.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Gingivitis , Enfermedades Periodontales , Periodontitis , Humanos , Anciano , Dióxido de Nitrógeno/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Conceptos Meteorológicos , Enfermedades Periodontales/etiología , Enfermedades Periodontales/inducido químicamente , Periodontitis/inducido químicamente , Gingivitis/inducido químicamente , Gingivitis/epidemiología , China , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis
11.
Angew Chem Int Ed Engl ; 62(43): e202309968, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37664907

RESUMEN

Lithium-sulfur (Li-S) batteries are promising due to ultrahigh theoretical energy density. However, their cycling lifespan is crucially affected by the electrode kinetics of lithium polysulfides. Herein, the polysulfide solvation structure is correlated with polysulfide electrode kinetics towards long-cycling Li-S batteries. The solvation structure derived from strong solvating power electrolyte induces fast anode kinetics and rapid anode failure, while that derived from weak solvating power electrolyte causes sluggish cathode kinetics and rapid capacity loss. By contrast, the solvation structure derived from medium solvating power electrolyte balances cathode and anode kinetics and improves the cycling performance of Li-S batteries. Li-S coin cells with ultra-thin Li anodes and high-S-loading cathodes deliver 146 cycles and a 338 Wh kg-1 pouch cell undergoes stable 30 cycles. This work clarifies the relationship between polysulfide solvation structure and electrode kinetics and inspires rational electrolyte design for long-cycling Li-S batteries.

12.
Angew Chem Int Ed Engl ; 62(48): e202313028, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37851474

RESUMEN

Coordination engineering for single-atom sites has drawn increasing attention, yet its chemical synthesis remains a tough issue, especially for tailorable coordination structures. Herein, a molecular recognition strategy is proposed to fabricate single-atom sites with regulable local coordination structures. Specifically, a heteroatom-containing ligand serves as the guest molecule to induce coordination interaction with the metal-containing host, precisely settling the heteroatoms into the local structure of single-atom sites. As a proof of concept, thiophene is selected as the guest molecule, and sulfur atoms are successfully introduced into the local coordination structure of iron single-atom sites. Ultrahigh oxygen reduction electrocatalytic activity is achieved with a half-wave potential of 0.93 V versus reversible hydrogen electrode. Furthermore, the strategy possesses excellent universality towards diversified types of single-atom sites. This work makes breakthroughs in the fabrication of single-atom sites and affords new opportunities in structural regulation at the atomic level.

13.
J Am Chem Soc ; 144(32): 14638-14646, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35791913

RESUMEN

Lithium-sulfur (Li-S) batteries have great potential as high-energy-density energy storage devices. Electrocatalysts are widely adopted to accelerate the cathodic sulfur redox kinetics. The interactions among the electrocatalysts, solvents, and lithium salts significantly determine the actual performance of working Li-S batteries. Herein, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), a commonly used lithium salt, is identified to aggravate surface gelation on the MoS2 electrocatalyst. In detail, the trifluoromethanesulfonyl group in LiTFSI interacts with the Lewis acidic sites on the MoS2 electrocatalyst to generate an electron-deficient center. The electron-deficient center with high Lewis acidity triggers cationic polymerization of the 1,3-dioxolane solvent and generates a surface gel layer that reduces the electrocatalytic activity. To address the above issue, Lewis basic salt lithium iodide (LiI) is introduced to block the interaction between LiTFSI and MoS2 and inhibit the surface gelation. Consequently, the Li-S batteries with the MoS2 electrocatalyst and the LiI additive realize an ultrahigh actual energy density of 416 W h kg-1 at the pouch cell level. This work affords an effective lithium salt to boost the electrocatalytic activity in practical working Li-S batteries and deepens the fundamental understanding of the interactions among electrocatalysts, solvents, and salts in energy storage systems.

14.
Allergol Immunopathol (Madr) ; 50(2): 7-15, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35257540

RESUMEN

BACKGROUND: As a systemic inflammatory reaction, sepsis is associated with various organ dysfunctions. The capillary leakage and the imbalance between T helper 17 and regulatory T (Th17/Treg) cells are associated with sepsis-induced lung injury. Taxifolin (TXL) has been found to play a vital role in regulating this diverse disease. However, the detailed functioning and mechanism of TXL in regulating sepsis-induced lung capillary leak remain elusive. METHODS: Balb/c mice were used to establish sepsis-induced lung injury model through administration of lipopolysaccharide (LPS). The structure of lung tissues was observed by using hematoxylin & eosin staining. Protein level and total cells in bronchoalveolar lavage fluid (BALF) were measured by bicinchoninic acid (BCA) protein assay kit and hematimetry assay, respectively. Quantitative real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay were employed to detect the level of inflammatory cytokines. The content of Th17 and Treg cells were measured by flow cytometry analysis. Western blot assay was used to determine the protein level of retinoid-related orphan receptor-γt (RORγt), Forkhead box P3 (Foxp3), Janus kinase 2 (JAK2), phospho(p)-JAK2, signal transducer and activator of transcription 3 (STAT3), and phospho(p)-STAT3. RESULTS: Taxifolin effectively prolonged the survival period of sepsis mice and alleviated LPS-induced lung injury in a dose-dependent manner. Moreover, TXL reduced LPS-induced increase in protein levels and T cell content in BALF, and effectively restored the wet:dry ratio of lung tissue and tissue permeability. Treating with TXL notably inhibited the production of pro-inflammatory cytokines induced by sepsis and influenced the balance between Th17 and Treg cells. Furthermore, TXL treatment suppressed the activation of JAK/STAT3 signaling pathway in a dose-dependent manner. CONCLUSION: Our findings revealed that TXL alleviated sepsis-induced capillary leak in the lungs of mice by regulating JAK/STAT3 signaling pathway.


Asunto(s)
Factor de Transcripción STAT3 , Sepsis , Animales , Modelos Animales de Enfermedad , Humanos , Pulmón/metabolismo , Ratones , Quercetina/análogos & derivados , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Células Th17
15.
Angew Chem Int Ed Engl ; 61(33): e202208042, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35679060

RESUMEN

Aqueous zinc-air batteries possess inherent safety and are especially commendable facing high-temperature working conditions. However, their working feasibility at high temperatures has seldom been investigated. Herein, the working feasibility of high-temperature zinc-air batteries is systemically investigated. The effects of temperature on air cathode, zinc anode, and aqueous electrolyte are decoupled to identify the favorable and unfavorable factors. Specifically, parasitic hydrogen evolution reaction strengthens at high temperatures and leads to declined anode Faraday efficiency, which is identified as the main bottleneck. Moreover, zinc-air batteries demonstrate cycling feasibility at 80 °C. This work reveals the potential of zinc-air batteries to satisfy energy storage at high temperatures and guides further development of advanced batteries towards harsh working conditions.

16.
Angew Chem Int Ed Engl ; 61(7): e202114671, 2022 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-34889012

RESUMEN

Lithium-sulfur (Li-S) batteries are deemed as future energy storage devices due to ultrahigh theoretical energy density. Cathodic polysulfide electrocatalysts have been widely investigated to promote sluggish sulfur redox kinetics. Probing the surface structure of electrocatalysts is vital to understanding the mechanism of polysulfide electrocatalysis. In this work, we for the first time identify surface gelation on disulfide electrocatalysts. Concretely, the Lewis acid sites on disulfides trigger the ring-opening polymerization of the dioxolane solvent to generate a surface gel layer, covering disulfides and reducing the electrocatalytic activity. Accordingly, a Lewis base triethylamine (TEA) is introduced as a competitive inhibitor. Consequently, Li-S batteries with disulfide electrocatalysts and TEA afford high specific capacity and improved rate responses. This work affords new insights on the actual surface structure of electrocatalysts in Li-S batteries.

17.
Angew Chem Int Ed Engl ; 61(42): e202208743, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-35961889

RESUMEN

The performance of rechargeable lithium (Li) batteries is highly correlated with the structure of solid electrolyte interphase (SEI). The properties of a working anode are vital factors in determining the structure of SEI; however, the correspondingly poor understanding hinders the rational regulation of SEI. Herein, the electrode potential and anode material, two critical properties of an anode, in dictating the structural evolution of SEI were investigated theoretically and experimentally. The anode potential is identified as a crucial role in dictating the SEI structure. The anode potential determines the reduction products in the electrolyte, ultimately giving rise to the mosaic and bilayer SEI structure at high and low potential, respectively. In contrast, the anode material does not cause a significant change in the SEI structure. This work discloses the crucial role of electrode potential in dictating SEI structure and provides rational guidance to regulate SEI structure.

18.
J Am Chem Soc ; 143(47): 19865-19872, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34761937

RESUMEN

Lithium-sulfur (Li-S) batteries constitute promising next-generation energy storage devices due to the ultrahigh theoretical energy density of 2600 Wh kg-1. However, the multiphase sulfur redox reactions with sophisticated homogeneous and heterogeneous electrochemical processes are sluggish in kinetics, thus requiring targeted and high-efficient electrocatalysts. Herein, a semi-immobilized molecular electrocatalyst is designed to tailor the characters of the sulfur redox reactions in working Li-S batteries. Specifically, porphyrin active sites are covalently grafted onto conductive and flexible polypyrrole linkers on graphene current collectors. The electrocatalyst with the semi-immobilized active sites exhibits homogeneous and heterogeneous functions simultaneously, performing enhanced redox kinetics and a regulated phase transition mode. The efficiency of the semi-immobilizing strategy is further verified in practical Li-S batteries that realize superior rate performances and long lifespan as well as a 343 Wh kg-1 high-energy-density Li-S pouch cell. This contribution not only proposes an efficient semi-immobilizing electrocatalyst design strategy to promote the Li-S battery performances but also inspires electrocatalyst development facing analogous multiphase electrochemical energy processes.

19.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2753-2759, 2021 Jun.
Artículo en Zh | MEDLINE | ID: mdl-34296572

RESUMEN

Through the investigation of a large number of both domestic and overseas literatures and related quality standards, chemical compositions, quality evaluation system and quality control methods of Succus Bambusae were systematic summarized in this study. There were abundant chemical constituents in Succus Bambusae, mainly including volatile ingredients, amino acids, flavonoids, trace elements and vitamins, with high medicinal and edible value. The quality control methods involved traditional morphological identification, spectroscopy, chromatography and other techniques. However, the current quality standards of Succus Bambusae are relatively low, lacking safety indicators, and cannot effectively ensure its quality, seriously affecting the safety and effectiveness of its clinical use. Therefore, it is particularly important to establish a set of highly sensitive and specific quality evaluation system for Succus Bambusae. In this paper, the current research status of the chemical compositions and quality standards of Succus Bambusae were reviewed, with the purpose of providing a basis for further improvement of its quality evaluation system.


Asunto(s)
Medicamentos Herbarios Chinos , Flavonoides , Control de Calidad
20.
Crit Rev Eukaryot Gene Expr ; 30(3): 253-264, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32749112

RESUMEN

This article serves to evaluate the association of polymorphisms of mismatch repair genes (hMLH1 and hMSH2) with breast cancer (BC) susceptibility through a meta-analysis. Our methods involved extensive research in Chinese and English databases that examined the association of hMLH1 and hMSH2 polymorphisms with susceptibility to BC, strictly abiding by established inclusion and exclusion criteria. Software Stata 12.0 was used for statistical data analysis. A total of 12 studies were available for meta-analysis, published between 2014 and 2017, of which respectively 9 studies explored the association of hMLH1 (rs1799977 A > G and rs63750447 T > A) and 3 studies explored the association of hMSH2 (rs4987188 [Gly322Asp] and rs17217772 [Asn127Ser]) with patients' susceptibility to BC. The results showed that both the rs1799977 A > G polymorphism GA + GG genotype (especially in the Caucasian population) and the rs63750447 T > A polymorphism TA + AA genotype in the hMLH1 gene increased patients' susceptibility to BC. The genotype detection method was selected as a target for subgroup analysis. According to studies where MassARRAY assay was conducted, the rs1799977 A > G polymorphism was correlated with BC susceptibility in the dominant model, while rs4987188 (Gly322Asp) and rs17217772 (Asn127Ser) of the hMSH2 gene presented no observable correlation with the risk for BC. Both the rs1799977 A > G and rs63750447 T > A polymorphisms in the hMLH1 gene showed a significant association with a markedly increased risk for BC, while rs4987188 (Gly322Asp) and rs17217772 (Asn127Ser) of the hMSH2 gene were not clearly correlated with BC susceptibility.


Asunto(s)
Neoplasias de la Mama/genética , Homólogo 1 de la Proteína MutL/genética , Proteína 2 Homóloga a MutS/genética , Adulto , Anciano , Anciano de 80 o más Años , Reparación de la Incompatibilidad de ADN , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Adulto Joven
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