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1.
Small ; : e2307900, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334199

RESUMO

As a crucial component responsible for the oxygen reduction reaction (ORR), cobalt-rich perovskite-type cathode materials have been extensively investigated in protonic ceramic fuel cell (PCFC). However, their widespread application at a commercial scale is considerably hindered by the high cost and inadequate stability. In response to these weaknesses, the study presents a novel cobalt-free perovskite oxide, Ba0.95 La0.05 (Fe0.8 Zn0.2 )0.95 O3-δ (BLFZ0.95), with the triple-conducting (H+ |O2- |e- ) property as an active and robust air electrode for PCFC. The B-site deficiency state contributes significantly to the optimization of crystal and electronic structure, as well as the increase in oxygen vacancy concentration, thus in turn favoring the catalytic capacity. As a result, the as-obtained BLFZ0.95 electrode demonstrates exceptional electrochemical performance at 700 °C, representing extremely low area-specific resistance of 0.04 Ω cm2 in humid air (3 vol.% H2 O), extraordinarily high peak power density of 1114 mW cm-2 , and improved resistance against CO2 poisoning. Furthermore, the outstanding long-term durability is achieved without visible deterioration in both symmetrical and single cell modes. This study presents a simple but crucial case for rational design of cobalt-free perovskite cathode materials with appreciable performance via B-site deficiency regulation.

2.
Small ; 20(27): e2312091, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38308418

RESUMO

Grafted biopolymer binders are demonstrated to improve the processability and cycling stability of the silicon (Si) nanoparticle anodes. However, there is little systematical exploration regarding the relationship between grafting density and performance of grafted binder for Si anodes, especially when Si particles exceed the critical breaking size. Herein, a series of guar gum grafted polyacrylamide (GP) binders with different grafting densities are designed and prepared to determine the optimal grafting density for maximizing the electrochemical performance of Si submicroparticle (SiSMP) anodes. Among various GP binders, GP5 with recommended grafting density demonstrates the strongest adhesion strength, best mechanical properties, and highest intrinsic ionic conductivity. These characteristics enable the SiSMP electrodes to sustain the electrode integrity and accelerate lithium-ion transport kinetics during cycling, resulting in high capacity and stable cyclability. The superior role of GP5 binder in enabling robust structure and stable interface of SiSMP electrodes is revealed through the PeakForce atomic force microscopy and in situ differential electrochemical mass spectrometry. Furthermore, the stable cyclabilities of high-loading SiSMP@GP5 electrode with ultralow GP5 content (1 wt%) at high areal capacity as well as the good cyclability of Ah-level LiNi0.8Co0.1Mn0.1O2/SiSMP@GP5 pouch cell strongly confirms the practical viability of the GP5 binder.

3.
Small ; : e2403600, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949410

RESUMO

BiVO4-based photoanode is one of the most promising photoanodes for photoelectrocatalytic water splitting. However, the serious problem of interface charge recombination limits its further development. Here, a Mo:BiVO4/NiOx/CPF-TCzB/NiCoBi photoanode is constructed with double hole transport layer and an energy level gradient to achieve an effective photo-generated holes extraction and accumulation at the surface electrocatalyst. The conjugated polycarbazole framework CPF-TCzB is used as hole transport layer to eliminate the charge recombination center between Mo:BiVO4 and NiCoBi electrocatalyst and realize the extraction and storage of photo-generated hole; NiOx nanoparticles are further inserted between Mo:BiVO4 and CPF-TCzB to form a gradient energy level, eliminating the energy level barrier and optimizing band alignment. As a result, Mo:BiVO4/NiOx/CPF-TCzB/NiCoBi achieves a much higher photocurrent densities of 3.14 mA cm-2 than that of Mo:BiVO4 (0.42 mA cm-2) at 0.6 V versus RHE. This work provides an specific way to adjust the band structure of BiVO4-based photoanodes and realize efficient hole extraction and storage for PEC water splitting.

4.
Chem Rev ; 122(1): 957-999, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34709781

RESUMO

Atomically thin materials (ATMs) with thicknesses in the atomic scale (typically <5 nm) offer inherent advantages of large specific surface areas, proper crystal lattice distortion, abundant surface dangling bonds, and strong in-plane chemical bonds, making them ideal 2D platforms to construct high-performance electrode materials for rechargeable metal-ion batteries, metal-sulfur batteries, and metal-air batteries. This work reviews the synthesis and electronic property tuning of state-of-the-art ATMs, including graphene and graphene derivatives (GE/GO/rGO), graphitic carbon nitride (g-C3N4), phosphorene, covalent organic frameworks (COFs), layered transition metal dichalcogenides (TMDs), transition metal carbides, carbonitrides, and nitrides (MXenes), transition metal oxides (TMOs), and metal-organic frameworks (MOFs) for constructing next-generation high-energy-density and high-power-density rechargeable batteries to meet the needs of the rapid developments in portable electronics, electric vehicles, and smart electricity grids. We also present our viewpoints on future challenges and opportunities of constructing efficient ATMs for next-generation rechargeable batteries.

5.
Artif Organs ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660762

RESUMO

BACKGROUND: Vascular smooth muscle cells (VSMCs) are commonly used as seed cells in tissue-engineered vascular constructions. However, their variable phenotypes and difficult to control functions pose challenges. This study aimed to overcome these obstacles using a three-dimensional culture system. METHODS: Calf VSMCs were administered tumor necrosis factor-alpha (TNF-α) before culturing in two- and three-dimensional well plates and polyglycolic acid (PGA) scaffolds, respectively. The phenotypic markers of VSMCs were detected by immunofluorescence staining and western blotting, and the proliferation and migration abilities of VSMCs were detected by CCK-8, EDU, cell counting, scratch, and Transwell assays. RESULTS: TNF-α rapidly decreased the contractile phenotypic markers and elevated the synthetic phenotypic markers of VSMCs, as well as markedly increasing the proliferation and migration ability of VSMCs under two- and three-dimensional culture conditions. CONCLUSIONS: TNF-α can rapidly induce a phenotypic shift in VSMCs and change their viability on PGA scaffolds.

6.
Nano Lett ; 23(14): 6512-6519, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37405910

RESUMO

In this work, the impact of metallic and dielectric conducting substrates, gold and indium tin oxide (ITO)-coated glass, on the whispering gallery modes (WGMs) of semiconductor π-conjugated polymer microspheres is investigated. Hyperspectral mapping was performed to obtain the excitation-position-dependent emission spectra of the microspheres. Substrate-dependent quenching of WGMs sensitive to mode polarization was observed and explained. On a glass substrate, both transverse-electric (TE) and transverse-magnetic (TM) WGMs are quenched due to frustrated total internal reflection. On a gold substrate, however, only the TM WGMs are allowed in symmetry to leak into surface plasmons. An atomically flat gold substrate with subwavelength slits was used to experimentally verify the leakage of WGMs into the surface plasmon polaritons (SPPs). This work provides insight into the damping mechanisms of WGMs in microspheres on metallic and dielectric substrates.

7.
Small ; 19(39): e2300802, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37259273

RESUMO

Stable cycling of LiCoO2 (LCO) cathode at high voltage is extremely challenging due to the notable structural instability in deeply delithiated states. Here, using the sol-gel coating method, LCO materials (LMP-LCO) are obtained with bulk Mg-doping and surface LiMgPO4 /Li3 PO4 (LMP/LPO) coating. The experimental results suggest that the simultaneous modification in the bulk and at the surface is demonstrated to be highly effective in improving the high-voltage performance of LCO. LMP-LCO cathodes deliver 149.8 mAh g-1 @4.60 V and 146.1 mAh g-1 @4.65 V after 200 cycles at 1 C. For higher cut-off voltages, 4.70 and 4.80 V, LMP-LCO cathodes still achieve 144.9 mAh g-1 after 150 cycles and 136.8 mAh g-1 after 100 cycles at 1 C, respectively. Bulk Mg-dopants enhance the ionicity of CoO bond by tailoring the band centers of Co 3d and O 2p, promoting stable redox on O2- , and thus enhancing stable cycling at high cut-off voltages. Meanwhile, LMP/LPO surface coating suppresses detrimental surface side reactions while allowing facile Li-ion diffusion. The mechanism of high-voltage cycling stability is investigated by combining experimental characterizations and theoretical calculations. This study proposes a strategy of surface-to-bulk simultaneous modification to achieve superior structural stability at high voltages.

8.
Chemistry ; 29(34): e202300225, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-36967610

RESUMO

Boosting oxygen evolution reaction by local surface plasmon resonance (LSPR) provides breakthrough opportunities for the promotion of solar energy conversion; the potential of LSPR, however, has rarely been tapped and investigated. Here, we report the precise regulation of commercial Au nanoparticles plasmonic nanomaterial and OER electrocatalysts, viz., the NiCoOx electrocatalytic layer with hole transport ability and photothermal effect is prepared on the surface of Au nanoparticles by photoelectrodeposition. The NiCoOx layer not only increases the transmission distance of holes generated by plasmonic Au nanoparticles, but also reduce the agglomeration of plasmonic Au nanoparticles during long-time OER reaction, which greatly improves the OER catalytic ability. The current density of NiCoOx /Au anode achieves 16.58 mA cm-2 at 2.0 V versus RHE, which is about 6.5 times of pristine NiCoOx anode (2.56 mA cm-2 ) and 47 times of pristine Au anode (0.35 mA cm-2 ). More importantly, with the LSPR and photothermal effect of plasmonic Au nanoparticles, the NiCoOx /Au anode provides additional current density of 7.01 mA cm-2 after illumination, and maintains no attenuation for more than 2000 s. Benefiting from the solution of agglomeration problem of plasmonic Au nanoparticles in the long-time OER process and the effective utilization of generated holes of plasmonic Au nanoparticles, this design can provide guidance for the application of plasmonic materials in the field of electrocatalysis.

9.
Angew Chem Int Ed Engl ; 62(17): e202301570, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36850048

RESUMO

Zn electrodes in aqueous media exhibit an unstable Zn/electrolyte interface due to severe parasitic reactions and dendrite formation. Here, a dynamic Zn interface modulation based on the molecular switch strategy is reported by hiring γ-butyrolactone (GBL) in ZnCl2 /H2 O electrolyte. During Zn plating, the increased interfacial alkalinity triggers molecular switch from GBL to γ-hydroxybutyrate (GHB). GHB strongly anchors on Zn surface via triple Zn-O bonding, leading to suppressive hydrogen evolution and texture-regulated Zn morphology. Upon Zn stripping, the fluctuant pH turns the molecular switch reaction off through the cyclization of GHB to GBL. This dynamic molecular switch strategy enables high Zn reversibility with Coulombic efficiency of 99.8 % and Zn||iodine batteries with high-cyclability under high Zn depth of discharge (50 %). This study demonstrates the importance of dynamic modulation for Zn electrode and realizes the reversible molecular switch strategy to enhance its reversibility.

10.
Cancer ; 128(7): 1467-1474, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34910297

RESUMO

BACKGROUND: This multicenter clinical trial was designed to evaluate the efficacy and safety of thalidomide (THD) in preventing oral mucositis (OM) in patients with nasopharyngeal carcinoma (NPC) undergoing concurrent chemoradiotherapy (CCRT). METHODS: Patients with locally advanced NPC were randomly assigned to either a THD group or a control group. All 160 patients received radical intensity-modulated radiotherapy plus cisplatin-based concurrent chemotherapy and basic oral hygiene guidance. Patients in the THD group received additional THD at the beginning of CCRT. The primary end points were the latency period and the incidence of OM. The secondary end points were mouth and throat soreness (MTS), weight loss, short-term efficacy, and adverse events. RESULTS: The median latency period of OM was 30 and 14 days in the THD and control groups, respectively (hazard ratio, 0.32; 95% confidence interval, 0.23-0.35; P < .0001). The incidence of OM and severe OM (World Health Organization grade 3 or higher) was significantly lower in the THD group than the control group (87.5% vs 97.5% [P = .016] and 27.5% vs 46.3% [P = .014], respectively). THD treatment also remarkably reduced the intensity of MTS and the degree of weight loss. In comparison with the control group, the incidence of nausea, vomiting, and insomnia was significantly decreased, whereas the incidence of dizziness and constipation was obviously increased in the THD group. The objective response rates 3 months after CCRT were similar between the groups. CONCLUSIONS: THD prolonged the latency period, reduced the incidence of OM, and did not affect the short-term efficacy of CCRT in patients with NPC. LAY SUMMARY: Oral mucositis is the most common complication of nasopharyngeal carcinoma during chemoradiotherapy; it decreases the patient's quality of life, and ideal mucosal protective agents are lacking. A few basic research and preclinical studies have shown that thalidomide may be an approach to ameliorating oral mucositis. The results of the current study confirm that thalidomide has a protective effect against oral mucositis in patients who have received chemoradiotherapy for nasopharyngeal carcinoma.


Assuntos
Neoplasias Nasofaríngeas , Estomatite , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Cisplatino , Humanos , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Qualidade de Vida , Estomatite/etiologia , Estomatite/prevenção & controle , Talidomida/efeitos adversos
11.
Surg Endosc ; 36(4): 2524-2531, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34231062

RESUMO

BACKGROUND: Endoscopic thyroidectomy is widely performed as it does not result in neck scar. However, there is a paucity of reports pertaining to completely endoscopic lateral neck dissection (LND). In this study, we introduce our step-wise approach for performing endoscopic selective LND via the chest-breast approach. We refer to this approach as Qin's seven steps. METHODS: The Qin's seven steps are: (1) establishment of working space range; (2) dissection of lymph nodes between the SCM and the sternohyoid muscle (level IV) and exposure of omohyoid; (3) dissection of lymph nodes at level IV; (4) dissection of lymph nodes at level III; (5) dissection of lymph nodes at carotid triangle (level III); (6) exposure of accessory nerve and dissection of lymph nodes at level II a; (7) dissection of lymph nodes at level II b. We reviewed the clinical data of 35 patients with papillary thyroid cancer (PTC) who were operated using the Qin's seven steps. RESULTS: All 35 patients successfully underwent LND; bilateral LND was performed in 5 patients. The mean tumor size was 1.8 ± 1.0 cm; seven patients had multiple lesions. The mean number of retrieved lymph nodes in level II, III and IV were 8.8 ± 5.6, 6.1 ± 4.0 and 9.3 ± 5.1, respectively. As for complications, there were 3 cases of accessory nerve injury and 1 case of hypoglossal nerve injury. Internal jugular vein injury, cervical plexus injury and lymphatic leakage occurred in 2, 7, and 1 patients, respectively. CONCLUSION: The Qin's seven steps for performing endoscopic selective LND could be safely used in PTC patients with lateral lymph node metastasis. Satisfactory results were achieved in the short-term follow-up period. We recommend the use of Qin's seven steps for PTC patients who are not desirous of neck scar.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Carcinoma Papilar/cirurgia , Cicatriz/patologia , Humanos , Linfonodos/patologia , Esvaziamento Cervical/métodos , Estudos Retrospectivos , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos
12.
Surg Endosc ; 36(12): 9092-9098, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35732836

RESUMO

BACKGROUND: Recent years there have been witnessed considerable advances in endoscopic selective lateral neck dissection (LND). However, dissection of lymph nodes at level IV and level VI via the chest approach is inherently challenging. In this study, we used combined trans-oral and chest approach for endoscopic thyroidectomy in patients with cT1-2N1bM0 papillary thyroid carcinoma (PTC). METHODS: Clinical characteristics and surgical outcomes of ten patients with cT1-2N1bM0 PTC who underwent endoscopic thyroidectomy via combination of trans-oral and chest approach between September 2020 and September 2021 were retrospectively reviewed. RESULTS: All 10 patients successfully underwent total thyroidectomy and selective LND via chest approach, while central neck dissection (CND) and supplementary dissection of lymph nodes at level IV were performed via the trans-oral approach. The mean number of positive/retrieved level II, III-IV, and VI lymph nodes were 0.6 ± 1.0/9.8 ± 5.0, 4.6 ± 2.8/23.1 ± 4.7, and 4.9 ± 3.4/10.3 ± 4.6, respectively. Four patients developed transient hypoparathyroidism which spontaneously resolved within 1 month. Five patients developed numbness of lateral neck and ear and one patient experienced limb lift restriction. No other complications or tumor recurrence occurred during follow-up. CONCLUSION: It is feasible to perform total thyroidectomy, CND, and selective LND via combined trans-oral and chest approach, and satisfactory short-term outcomes were observed in this cohort. This approach may offer one more option for cT1-2N1bM0 PTC patients, especially those in whom metastatic lymph nodes at level IV or level VI are detected by preoperative examination.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Tireoidectomia , Câncer Papilífero da Tireoide/cirurgia , Carcinoma Papilar/cirurgia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Recidiva Local de Neoplasia/cirurgia , Esvaziamento Cervical/efeitos adversos , Linfonodos/patologia
13.
BMC Surg ; 22(1): 270, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831846

RESUMO

BACKGROUND: This study aimed to evaluate the feasibility and safety of the trans-oral endoscopic thyroidectomy vestibular approach (TOETVA) with neuroprotection techniques for the surgical management of papillary thyroid carcinoma (PTC). METHODS: Patients with PTC who underwent TOETVA between December 2016 and July 2020 were included in this study, and their relevant clinical characteristics, operational details, and surgical outcomes were reviewed and extracted from their medical records for further analysis. RESULTS: A total of 75 patients successfully underwent TOETVA with zero conversions. Unilateral lobectomy with isthmectomy and total thyroidectomy were completed for 58 and 17 patients, respectively, all using our unique neuroprotective procedure and ipsilateral central neck dissection (CND). The mean number of retrieved lymph nodes versus positive lymph nodes was 6.8 ± 3.7 vs. 1.5 ± 2.3. Postoperative complications included three cases of transient superior laryngeal nerve (SLN) palsy (4.0%), five cases of transient recurrent laryngeal nerve (RLN) palsy (6.7%), 14 cases of transient hypoparathyroidism (18.7%), two cases of numb chin (2.7%) and two cases of flap perforation (2.7%). The follow-up period for patients with PTC lasted for 15.6 ± 10.9 months, during which no other complications or tumor recurrence were observed. CONCLUSION: TOETVA can be safely performed for patients with PTC with satisfactory results during the short-term follow-up period. Our neuroprotection techniques can be integrated into TOETVA, which is worth recommending for PTC patients who desire better cosmetic surgical outcomes.


Assuntos
Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Tireoidectomia , Estudos de Viabilidade , Humanos , Neuroproteção , Complicações Pós-Operatórias/epidemiologia , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Resultado do Tratamento
14.
Sensors (Basel) ; 22(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36365851

RESUMO

Two-dimensional (2D) perovskite have been widely researched for solar cells, light-emitting diodes, photodetectors because of their excellent environmental stability and optoelectronic properties in comparison to three-dimensional (3D) perovskite. In this study, we demonstrate the high response of 2D-(PEA)2PbBr4 perovskite of the horizontal vapor sensor was outstandingly more superior than 3D-MAPbBr3 perovskite. 2D transverse perovskite layer have the large surface-to-volume ratio and reactive surface, with the charge transfer mechanism, which was suitable for vapor sensing and trapping. Thus, 2D perovskite vapor sensors demonstrate the champion current response ratio R of 107.32 under the ethanol vapors, which was much faster than 3D perovskite (R = 2.92).

15.
BMC Oral Health ; 22(1): 76, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35300666

RESUMO

BACKGROUND: Obesity and dental caries among children and adolescents are growing worldwide public health problems. They share some common and modifiable influences. The objective of this study was to evaluate the prevalence of obesity and dental caries among children and adolescents in Huizhou and explore the association between Body Mass Index (BMI) category and dental caries. METHODS: This cross-sectional study enrolled 105,181 students (55,500 males and 49,681 females) from 87 schools in Huizhou. Height and weight were measured, and BMI was calculated. Based on Chinese BMI standards, students were classified into underweight, normal weight, overweight, and obesity groups. Dental caries was diagnosed according to criteria recommended by World Health Organization (WHO). We used the Chi-square test to compare proportions of groups and performed Association Rules Mining to identify patterns and combinations of BMI categories and dental caries. Finally, a multilevel logistic regression model was applied to analyze the association between BMI category and dental caries when confounders were considered. RESULTS: The prevalence of underweight, overweight, and obesity among children and adolescents was 7.56%, 8.85%, and 2.95%, respectively. The overall prevalence of dental caries was 58.10%, with a lower prevalence among boys than girls. Students from primary schools and remote towns more easily suffer from dental caries. Caries prevalence of students belonged to underweight, normal, overweight, and obesity was 65.6%, 58.8%, 49.6%, and 46.1% individually. With increasing BMI levels, the prevalence of dental caries decreased. Further, this trend still exists in each subgroup of gender, educational stage, school type, and area. Association rules indicate underweight has a positive effect on the occurrence of dental caries, while overweight or obesity has a negative impact on the occurrence of dental caries. The three-level logistic regression model results show that BMI category is inversely associated with dental caries after adjusting confounders. CONCLUSION: Obesity is negatively associated with dental caries among children and adolescents in Huizhou. Further research is required to investigate how dietary habits, oral hygiene habits, and parental socioeconomic status mediate the association between BMI and dental caries.


Assuntos
Cárie Dentária , Adolescente , Índice de Massa Corporal , Criança , Estudos Transversais , Cárie Dentária/complicações , Cárie Dentária/epidemiologia , Feminino , Humanos , Masculino , Obesidade/complicações , Obesidade/epidemiologia , Sobrepeso/complicações , Sobrepeso/epidemiologia
16.
Angew Chem Int Ed Engl ; 61(29): e202205312, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35514288

RESUMO

Infinite coordination-polymer particles (CPPs) are promising materials for solar energy conversion with high efficiency. However, the range of organic ligands that may be used to create CPPs is limited, as are strategies for modification, thereby hindering the applications of such material. In this paper, competitive evolution-morphological and structural change from Zn-based crystallites to amorphous particles is described. Controlled contribution of organic linkers selectively derived six Zn-CPPs with multivariate characters. Based on the diversity of these substructures, hollow zinc oxide particles were initially formed by self-pyrolysis of CPPs and effectively modified by ultrathin doped nanosheets. The obtained double-sided heterojunctions offer fully-covered active sites, bringing together efficient light-excited charge-transfer nanochannels, which exhibit an excellent solar H2 -releasing activity (e.g., 4512.5 µmol h-1 g-1 ) and stable cyclability.

17.
Angew Chem Int Ed Engl ; 61(27): e202203698, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35441768

RESUMO

Capacity fading and voltage decay is one of the biggest obstacles for the practical application of Li-rich layered oxides due to the serious surface-related detrimental reactions. Herein, we develop a versatile and scalable method to construct a robust surface-integrated structure. All the designed samples deliver outstanding capacity and voltage stability, among which the Zn-treated sample possesses the best electrochemical performance. Its capacity retention is larger than 90 % after 400 cycles with a voltage decay ratio as small as 0.73 mV per cycle. What is more, the rules of surface-integrated structure with different cations in terms of capacity and voltage stability is further deciphered by combining with density function theory (DFT) calculations. It is found that to obtain advanced Li-rich layered oxide cathodes, cations in Li-sites should firstly ensure the binding energy of the surface-integrated structure in a lower level and then provide Bader charge for the nearest O atoms as small as possible.

18.
J Am Chem Soc ; 143(23): 8772-8779, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34085826

RESUMO

It has long been surmised that the circular polarization of luminescence (CPL) emitted by a chiral molecule or a molecular assembly should vary with the direction in which the photon is emitted. Despite its potential utility, this anisotropic CPL has not yet been demonstrated at the level of single molecules or supramolecular assemblies. Here we show that conjugated polymers bearing chiral side chains self-assemble into solid microspheres with a twisted bipolar interior, which are formed via liquid-liquid phase separation and subsequent condensation into a cholesteric lyotropic liquid crystalline mesophase. The resultant microspheres, when dispersed in methanol, exhibit CPL with a glum value as high as 0.23. The microspheres are mechanically robust enough to be handled with a microneedle under ambient conditions, allowing comprehensive examination of the angular anisotropy of CPL. The single microsphere is found to exhibit distinct angularly anisotropic birefringence and CPL with glum up to ∼0.5 in the equatorial plane, which is 2.5-fold greater than that along the polar axis. Such optically anisotropic solid materials are important for the application to next-generation microlight-emitting and visualizing devices as well as for fundamental optics studies of chiral light-matter interaction.

19.
J Gene Med ; 23(3): e3313, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33522046

RESUMO

BACKGROUND: Schizophrenia (SZ) is a serious hereditary mental disease with a low recovery rate, especially due to the lack of understanding about the cause of the disease. VRK2 is considered to be related to the pathogenesis of schizophrenia. In this study, we analyzed the correlation between VRK2, rs4380187 single-nucleotide polymorphism (SNP), and schizophrenia. METHODS: Peripheral blood DNA was extracted using a genomic DNA extraction kit. The DNA samples were genotyped using the Agena MassARRAY platform, and four genetic models were applied to compute the odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression. The p value was obtained by the chi-square and t test for independent samples. RESULTS: The C allele of rs4380187 SNP was significantly (p = 0.008) associated with decreased risk of SZ. The AA genotype of rs4380187 showed significantly (p = 0.009) lower frequency in cases with SZ than in controls and was associated with decreased risk of the disease. The frequency of the CA genotype of rs4380187 correlated with a 0.73-fold decreased risk of SZ (p = 0.033). In the co-dominant genetic model, the genotype of rs4380187 was associated with a decreased risk of SZ (p = 0.010). We also found that the log-additive model of rs4380187 significantly reduced the risk of SZ disease (p = 0.007). CONCLUSION: This study provides further evidence that rs4380187 SNP is associated with SZ. This genotype variation could be associated with the psychopathology and cognitive function in SZ.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/genética , Esquizofrenia/genética , Adulto , Alelos , Povo Asiático/genética , Biomarcadores , Estudos de Casos e Controles , China/epidemiologia , Feminino , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Razão de Chances , Adulto Jovem
20.
Small ; 17(2): e2006638, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33325635

RESUMO

Developing robust and highly efficient electrocatalysts for oxygen evolution reaction (OER) is critical for renewable, secure, and emission-free energy technologies. Perovskite Ba0.5 Sr0.5 Co0.8 Fe0.2 O3-δ (BSCF) has emerged as a promising OER electrocatalyst with desirable intrinsic activity. Inspired by the factor that substituting in transition-metal sublattice of the perovskite can further optimize the OER activity, herein, nickel-substituted BSCF is adopted, that is, Ba0.5 Sr0.5 Co0.8- x Fe0.2 Nix O3-δ (x = 0.05, 0.1, 0.2, denoted as BSCFNx, x = 5, 10, 20, respectively), as efficient and stable OER catalysts in alkaline solution. The phase structure, microchemistry, oxygen vacancy, and electrochemical activity of such samples are well-investigated. Endowed with an overpotential of only 278 mV at 10 mA cm-2 and a Tafel slope of merely 47.98 mV dec-1 , BSCFN20 exhibits the optimum OER activity. When constructing a two-electrode cell with BSCFN20 as anode and Pt/C as cathode (BSCFN20||Pt/C) for water splitting, it only requires a voltage of 1.63 V to achieve 50 mA cm-2 , and the BSCFN20||Pt/C remains stable within 80 h at 10 mA cm-2 , superior to the state-of-the-art RuO2 ||Pt/C counterpart. This work provides a feasible strategy for designing stable and highly active perovskite electrocatalysts for future energy storage and conversion.

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