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1.
Sci Total Environ ; 921: 171109, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38387563

RESUMEN

Microplastics (MPs), an emerging environmental contaminant, have raised growing health apprehension due to their detection in various human biospecimens. Despite extensive research into their prevalence in the environment and the human body, the ramifications of their existence within the enclosed confines of the human eye remain largely unexplored. Herein, we assembled a cohort of 49 patients with four ocular diseases (macular hole, macular epiretinal membrane, retinopathy and rhegmatogenous retinal detachment) from two medical centers. After processing the samples with an optimized method, we utilized Laser Direct Infrared (LD-IR) spectroscopy and Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) to analyze 49 vitreous samples, evaluating the characteristics of MPs within the internal environment of the human eye. Our results showed that LD-IR scanned a total of 8543 particles in the composite sample from 49 individual vitreous humor samples, identifying 1745 as plastic particles, predominantly below 50 µm. Concurrently, Py-GC/MS analysis of the 49 individual samples corroborated these findings, with nylon 66 exhibiting the highest content, followed by polyvinyl chloride, and detection of polystyrene. Notably, correlations were observed between MP levels and key ocular health parameters, particularly intraocular pressure and the presence of aqueous humor opacities. Intriguingly, individuals afflicted with retinopathy demonstrated heightened ocular health risks associated with MPs. In summary, this research provides significant insights into infiltration of MP pollutants within the human eye, shedding light on their potential implications for ocular health and advocating for further exploration of this emerging health risk.


Asunto(s)
Enfermedades de la Retina , Contaminantes Químicos del Agua , Humanos , Cuerpo Vítreo/química , Microplásticos , Plásticos/análisis , Cromatografía de Gases y Espectrometría de Masas , Contaminantes Químicos del Agua/análisis
2.
J Am Chem Soc ; 146(5): 2967-2976, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38155548

RESUMEN

Cobalt-based spinel oxides (i.e., Co3O4) are emerging as low-cost and selective electrocatalysts for the electrochemical nitrate reduction reaction (NO3-RR) to ammonia (NH3), although their activity is still unsatisfactory and the genuine active site is unclear. Here, we discover that the NO3-RR activity of Co3O4 is highly dependent on the geometric location of the Co site, and the NO3-RR prefers to occur at octahedral Co (CoOh) rather than tetrahedral Co (CoTd) sites. Moreover, CoOhO6 is electrochemically transformed to CoOhO5 along with the formation of O vacancies (Ov) during the process of NO3-RR. Both experimental and theoretic results reveal that in situ generated CoOhO5-Ov configuration is the genuine active site for the NO3-RR. To further enhance the activity of CoOh sites, we replace inert CoTd with different contents of Cu2+ cations, and a volcano-shape correlation between NO3-RR activity and electronic structures of CoOh is observed. Impressively, in 1.0 M KOH, (Cu0.6Co0.4)Co2O4 with optimized CoOh sites achieves a maximum NH3 Faradaic efficiency of 96.5% with an ultrahigh NH3 rate of 1.09 mmol h-1 cm-2 at -0.45 V vs reversible hydrogen electrode, outperforming most of other reported nonprecious metal-based electrocatalysts. Clearly, this work paves new pathways for boosting the NO3-RR activity of Co-based spinels by tuning local electronic structures of CoOh sites.

3.
Front Pediatr ; 11: 1273413, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37854031

RESUMEN

Background: In order to understand the research hotspots and trends in the field of retinopathy of prematurity (ROP), our study analyzed the relevant publications from 2003 to 2022 by using bibliometric analysis. Methods: The Citespace 6.2.R3 system was used to analyze the publications collected from the Web of Science Core Collection (WoSCC) database. Results: In total, 4,957 publications were included in this study. From 2003 to 2022, the number of publications gradually increased and peaked in 2022. The United States was the country with the most publications, while Harvard University was the most productive institution. The top co-cited journal PEDIATRICS is published by the United States. Author analysis showed that Hellström A was the author with the most publications, while Good WV was the top co-cited author. The co-citation analysis of references showed seven major clusters: genetic polymorphism, neurodevelopmental outcome, threshold retinopathy, oxygen-induced retinopathy, low birth weight infant, prematurity diagnosis cluster and artificial intelligence (AI). For the citation burst analysis, there remained seven keywords in their burst phases until 2022, including ranibizumab, validation, trends, type 1 retinopathy, preterm, deep learning and artificial intelligence. Conclusion: Intravitreal anti-vascular endothelial growth factor therapy and AI-assisted clinical decision-making were two major topics of ROP research, which may still be the research trends in the coming years.

4.
Angew Chem Int Ed Engl ; 62(40): e202309732, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37580313

RESUMEN

Heteroatom doping has emerged as a highly effective strategy to enhance the activity of metal-based electrocatalysts toward the oxygen evolution reaction (OER). It is widely accepted that the doping does not switch the OER mechanism from the adsorbate evolution mechanism (AEM) to the lattice-oxygen-mediated mechanism (LOM), and the enhanced activity is attributed to the optimized binding energies toward oxygen intermediates. However, this seems inconsistent with the fact that the overpotential of doped OER electrocatalysts (<300 mV) is considerably smaller than the limit of AEM (>370 mV). To determine the origin of this inconsistency, we select phosphorus (P)-doped nickel-iron mixed oxides as the model electrocatalysts and observe that the doping enhances the covalency of the metal-oxygen bonds to drive the OER pathway transition from the AEM to the LOM, thereby breaking the adsorption linear relation between *OH and *OOH in the AEM. Consequently, the obtained P-doped oxides display a small overpotential of 237 mV at 10 mA cm-2 . Beyond P, the similar pathway transition is also observed on the sulfur doping. These findings offer new insights into the substantially enhanced OER activity originating from heteroatom doping.

5.
Adv Mater ; 35(42): e2305598, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37433070

RESUMEN

Hydrazine-assisted water electrolysis provides new opportunities to enable energy-saving hydrogen production while solving the issue of hydrazine pollution. Here, the synthesis of compressively strained Ni2 P as a bifunctional electrocatalyst for boosting both the anodic hydrazine oxidation reaction (HzOR) and cathodic hydrogen evolution reaction (HER) is reported. Different from a multistep synthetic method that induces lattice strain by creating core-shell structures, a facile strategy is developed to tune the strain of Ni2 P via dual-cation co-doping. The obtained Ni2 P with a compressive strain of -3.62% exhibits significantly enhanced activity for both the HzOR and HER than counterparts with tensile strain and without strain. Consequently, the optimized Ni2 P delivers current densities of 10 and 100 mA cm-2 at small cell voltages of 0.16 and 0.39 V for hydrazine-assisted water electrolysis, respectively. Density functional theory (DFT) calculations reveal that the compressive strain promotes water dissociation and concurrently tunes the adsorption strength of hydrogen intermediates, thereby facilitating the HER process on Ni2 P. As for the HzOR, the compressive strain reduces the energy barrier of the potential-determining step for the dehydrogenation of *N2 H4 to *N2 H3 . Clearly, this work paves a facile pathway to the synthesis of lattice-strained electrocatalysts via the dual-cation co-doping.

6.
Mol Med Rep ; 26(6)2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36196888

RESUMEN

An interested reader of an article published in the journal Circulation Research [Krishnamurthy P, Rajasingh J, Lambers E, Qin G, Losordo DW and Kishore R: L­10 inhibits inflammation and attenuates left ventricular remodeling after myocardial infarction via activation of STAT3 and suppression of HuR. Circ Res 104: e9­18, 2008] drew to our attention that data featured in their paper had appeared subsequently in the abovementioned article by Yin et al in Molecular Medicine Reports in 2014. Specifically, Fig. 1 in the Mol Med Rep paper included the same histograms as those featured in Fig. 2 in the Circ Res paper; Fig. 2 in the Mol Med Rep paper contained data derived from Fig. 1 in the Circ Res paper; and Figs. 3­5 in both papers shared a substantial amount of the same data. Following an internal investigation, the Journal was able to confirm that this accusation of plagiarism was well­founded. On those grounds, the Editor of Molecular Medicine Reports has decided to retract this paper. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor deeply regrets the grievance that this matter has caused to the authors of the previously published article, and also any inconvenience caused to the readership of the Journal.

7.
Front Nutr ; 9: 993896, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36082028

RESUMEN

Background: Total laparoscopic total gastrectomy (TLTG) for gastric cancer, especially with overlap esophagojejunostomy, has been verified that it has advantages of minimally invasion, less intraoperative bleeding, and faster recovery. Meanwhile, early oral feeding (EOF) after the operation has been demonstrated to significantly promote early rehabilitation in patients, particularly with distal gastrectomy. However, due to the limited application of TLTG, there is few related research proving whether it is credible or safe to adopt EOF after TLTG (overlap esophagojejunostomy). So, it is urgent to start a prospective, multicenter, randomized clinical trials to supply high level evidence. Methods/design: This study is a prospective, multicenter, randomized controlled trial with 200 patients (100 in each group). These eligible participants are randomly allocated into two different groups, including EOF group and delay oral feeding (DOF) group after TLTG (overlap esophagojejunostomy). Anastomotic leakage will be carefully observed and recorded as the primary endpoints; the period of the first defecation and exhaust, postoperative length of stay and hospitalization expenses will be recorded as secondary endpoints to ascertain the feasibility and safety of adopting EOF after TLTG (overlap esophagojejunostomy). Discussion: Recently, the adoption of TLTG was limited due to its difficult anastomotic procedure, especially in vivo esophagojejunostomy. With the innovation and improvement of operating techniques, overlap esophagojejunostomy with linear staplers simplified the anastomotic steps and reduced operational difficulties after TLTG. Meanwhile, EOF had received increasing attention from surgical clinicians as a nutrition part of enhanced recovery after surgery (ERAS), which had shown better results in patients after distal gastrectomy. Considering the above factors, we implemented EOF protocol to evaluate the feasibility and safety of adopting EOF after TLTG (overlap esophagojejunostomy), which provided additional evidence for the development of clinical nutrition guidelines. Clinical trial registration: [www.chictr.org.cn], identifier [ChiECRCT20200440 and ChiCTR2000040692].

8.
Transl Cancer Res ; 11(6): 1644-1651, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35836510

RESUMEN

Background: Our previous study found an association between the expression of hypoxia-inducible factor-1alpha (HIF-1α) and annexin A3 (ANXA3) in colon cancer. ANXA3 correlated with expansion of CD133+ tumor cells in hepatocellular carcinoma cancer stem-like cells (CSCs), for which CD133 has been recognized as a typical marker in many cancer cells, including: gastric cancer, lung cancer and colorectal cancer. But the expression and association of HIF-1α, ANXA3 and CD133 in colon cancer has not been reported. The purpose of the present study was to evaluate the correlation among the expression of HIF-1α, ANXA3 and CD133 in human colon cancer and to investigate its clinicopathological parameters. Methods: The data for 35 patients diagnosed with colon adenocarcinoma in The First Affiliated Hospital of Chongqing Medical University and who had undergone colectomy, tumor and adjacent normal colon tissues were collected. The expressions of HIF-1α, ANXA3, and CD133 were measured by immunohistochemistry in colon cancer and surrounding non-tumor tissues and measured by using a semiquantitative score system. Finally, relationships between HIF-1α, ANXA3, and CD133 immunohistochemical staining and clinicopathologic variables were analyzed using the Fisher's exact probability test. Associations between the expression levels of HIF-1α, ANXA3, and CD133 were analyzed by the Spearman's rank correlation. Results: The positive rate of expression of HIF-1α in colon cancer and normal colon tissue was 80% (28/35) and 14% (5/35), 77% (27/35) and 20% (7/35) for ANXA3, and 71% (25/35) and 23% (8/35) for CD133, respectively. The coefficient of correlation for the association among HIF-1α, ANXA3 and CD133 showed that the expression of HIF-1α was positively related with ANXA3 and CD133 in colon cancer tissues (r1=0.408, P1=0.015, r2=0.474, P2=0.004) and a positive correlation was observed between the expression of ANXA3 and CD133 (r3=0.409, P3=0.015). Expression of HIF-1α, ANXA3 and CD133 were associated with tumor size, lymphatic metastasis and clinic stage of colon cancer (all P<0.05). Conclusions: HIF-1α, ANXA3 and CD133 were overexpressed in human colon cancer and showed positive correlations among themselves. The expression of HIF-1α, ANXA3 and CD133 were closely related to the size of the tumor, lymphatic metastasis and clinical stage of colon cancer, which indicated that they could be promising biomarkers for the study of colon CSCs and treatment of colon carcinoma.

9.
Small ; 18(1): e2104958, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34825485

RESUMEN

The efficiency of CO2 electroreduction has been largely limited by the activity of the catalysts as well as the three-phase interface. Herein, a multiscale strategy is proposed to synthesize hierarchical nanofibers covered by carbon nanotubes and embedded with cobalt nanoparticles (Co/CNT/HCNF). The confinement effect of carbon nanotubes can restrict the diameter of the cobalt particles down to several nanometers and prevent the easy corrosion of these nanoparticles. The three-dimensional carbon nanofibers, in size range of several hundred nanometers, improve the electrochemically active surface area, facilitate electron transfer, and accelerate CO2 transportation. These cross-linked carbon nanofibers eventually form a freestanding Co/CNT/HCNF membrane of dozens of square centimeters. Consequently, Co/CNT/HCNF produces CO with 97% faradaic efficiency at only -0.4 VRHE cathode potential in an H-type cell. From the regulation of catalyst nanostructure to the design of macrography devices, Co/CNT/HCNF membrane can be directly used as the gas-diffusion compartment in a flow cell device. Co/CNT/HCNF membrane generates CO with faradaic efficiencies higher than 90% and partial current densities greater than 300 mA cm-2 for at least 100-h stability. This strategy provides a successful example of efficient catalysts for CO2 electroreduction and also has the feasibility in other self-standing energy conversion devices.

10.
Food Chem Toxicol ; 154: 112315, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34082049

RESUMEN

Acrylamide has a variety of toxicities, including carcinogenicity, and can be present in food via the Maillard reaction in processing of certain foods. Previous studies have demonstrated that co-existing Maillard reaction products (MRPs) ameliorated acrylamide-induced abnormal physiological status in mice. This study is focused on the effects on hematological parameters, erythrocyte osmotic fragility, oxidative stress in plasma and liver, and contents of 8-hydroxy-2-deoxyguanosine (8-OHdG) in mice exposed to acrylamide and to acrylamide and MRPs derived from arginine and glucose. Acrylamide alone caused significant increases in liver indexes, erythrocyte osmotic fragility, malonaldehyde level in liver and 8-OHdG level in testis, and significant decreases in weight gain, hematological parameters, levels of glutathione, glutathione peroxidase and total superoxide dismutase in plasma. Whether MRPs and acrylamide were physically mixed or when the solution is prepared from heating the mixture of arginine, glucose and acrylamide, the presence of MRPs effectively reduced the adverse changes caused by acrylamide. These results suggest that the toxicity of acrylamide to mice can be ameliorated by MRPs, the common compositions simultaneously generated with acrylamide in food matrix.


Asunto(s)
Acrilamida/toxicidad , Arginina/química , Glucosa/química , Reacción de Maillard , 8-Hidroxi-2'-Desoxicoguanosina/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Femenino , Glutatión/sangre , Glutatión Peroxidasa/sangre , Hemólisis/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos ICR , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/sangre , Testículo/efectos de los fármacos , Testículo/metabolismo
11.
Dalton Trans ; 49(4): 972-976, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31894797

RESUMEN

An HCBP1 peptide-ruthenium conjugate (Ru-ß-Ala-FQHPSFI) as a potential candidate for targeted therapy of hepatoma was synthesized. Ru-ß-Ala-FQHPSFI shows drastically enhanced cytotoxicity and high selectivity for hepatoma cells versus noncancer liver cells. Raman imaging shows that this peptide-based drug can be taken up well by the hepatoma cells compared with the bare ruthenium complex (Ru) and the opposite sequence peptide-ruthenium conjugate (Ru-ß-Ala-IFSPHQF). This study presents a new strategy for the construction of tumor-targeting metal-based anticancer therapeutics.


Asunto(s)
Carcinoma Hepatocelular/patología , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Neoplasias Hepáticas/patología , Oligopéptidos/química , Rutenio/química , Secuencia de Aminoácidos , Células Hep G2 , Humanos
12.
Polymers (Basel) ; 11(7)2019 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-31277462

RESUMEN

The quality of polyacrylonitrile (PAN) precursor has a great influence on the properties of the resultant carbon fibers. In this paper, a novel comonomer containing the sulfonic group, 2-acrtlamido-2-methylpropane acid (AMPS), was introduced to prepare P(AN-co-AMPS) copolymers using itaconic acid (IA) as the control. The nanofibers of PAN, P(AN-co-IA), and P(AN-co-AMPS) were prepared using the electrospinning method. The effect of AMPS comonomer on the carbon nanofibers was studied using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Raman spectrum. The structural evolutions of PAN-based nanofibers were quantitatively tracked by FTIR and XRD during the thermal oxidative stabilization (TOS) process. The results suggested that P(AN-co-AMPS) nanofibers had the lower heat release rate (ΔH/ΔT = 26.9 J g-1 °C-1), the less activation energy of cyclization (Ea1 = 26.6 kcal/mol and Ea2 = 27.5 kcal/mol), and the higher extent of stabilization (Es and SI) during TOS process, which demonstrated that the AMPS comonomer improved the efficiency of the TOS process. The P(AN-co-AMPS) nanofibers had the better thermal stable structures. Moreover, the carbon nanofibers derived from P(AN-co-AMPS) precursor nanofibers had the better graphite-like structures (XG = 46.889). Therefore, the AMPS is a promising candidate comonomer to produce high performance carbon fibers.

14.
Angew Chem Int Ed Engl ; 58(13): 4318-4322, 2019 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-30714282

RESUMEN

Recently, metal-free, heteroatom-doped carbon nanomaterials have emerged as promising electrocatalysts for the oxygen evolution reaction (OER), but their synthesis is a tedious process involving energy-wasting calcination. Molecular electrocatalysts offer attractive catalysts for the OER. Here, phytic acid (PA) was selected to investigate the OER activity of carbons in organic molecules by DFT calculations and experiments. Positively charged carbons on PA were very active towards the OER. The PA molecules were fixed into a porous, conductive hydrogel with a superhydrophilic surface. This outperformed most metal-free electrocatalysts. Besides the active sites on PA, the high OER activity was also related to the porous and conductive networks on the hydrogel, which allowed fast charge and mass transport during the OER. Therefore, this work provides a metal-free, organic-molecule-based electrocatalyst to replace carbon nanomaterials for efficient OER.

15.
Angew Chem Int Ed Engl ; 57(47): 15476-15480, 2018 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-30284359

RESUMEN

A facile route to scalable production of N and S co-doped, hierarchically porous carbon nanofiber (NSHCF) membranes (ca. 400 cm2 membrane in a single process) is reported. As-synthesized NSHCF membranes are flexible and free-standing, allowing their direct use as cathodes for efficient electrochemical CO2 reduction reaction (CO2 RR). Notably, CO with 94 % Faradaic efficiency and -103 mA cm-2 current density are readily achieved with only about 1.2 mg catalyst loading, which are among the best results ever obtained by metal-free CO2 RR catalysts. On the basis of control experiments and DFT calculations, such outstanding CO Faradaic efficiency can be attributed to the co-doped pyridinic N and carbon-bonded S atoms, which effectively decrease the Gibbs free energy of key *COOH intermediate. Furthermore, hierarchically porous structures of NSHCF membranes impart a much higher density of accessible active sites for CO2 RR, leading to the ultra-high current density.

16.
Oncol Lett ; 16(4): 4285-4290, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30214562

RESUMEN

Short-term efficacy, adverse effects and the impact on quality of life (QoL) of a concomitant treatment with intensity-modulated radiation therapy (IMRT) and temozolomide (TMZ) in patients with brain metastases (BMs) from lung adenocarcinoma were evaluated. This study sought to confirm the benefit of adding TMZ to IMRT in patients with BMs from lung adenocarcinoma. Nine patients were enrolled and received a dose of 30 Gy in 10 daily fractions to clinical tumor volume (CTV) according to IMRT, then additional dose of 9 Gy in 3 fractions of IMRT was delivered to gross tumor volume (GTV) only with concomitant TMZ (75 mg/m2/day) orally during RT for 3 weeks. One patient achieved complete response (CR) (11.1%), 6 patients obtained partial response (PR) (66.7%), and there were no patients in progression. Therefore, objective response (OR) reached 77.8%. The main adverse effects included neutropenia, anemia, vomiting, fatigue and dizziness. Grade ≥3 of hematologic toxicities did not occur. However, the other 9 patients who received only intensity-modulated radiation had much worse results. The CR was 0, PR rate was 44.4%, OR rate was 44.4%. The results indicated that the benefit of adding TMZ to IMRT was confirmed in patients with BMs from lung adenocarcinoma. The treatment was active, a significant OR was observed, and achieved an improvement in QoL demonstrated by QoL grade (p<0.05).

17.
Small ; 14(42): e1802755, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30260576

RESUMEN

Nonprecious transition metal phosphides (TMPs) have emerged as robust electrocalysts for the hydrogen evolution reaction (HER). However, the TMPs suffer from low activity for water dissociation, which greatly limits the efficiency for alkaline HER. Here, a facile yet robust strategy is reported to boost the HER of metal phosphides by coating defective TiO2 overlayers. The oxygen vacancies (Ov ) on defective TiO2 overlayers are found to possess high activity for adsorption and dissociation of water, thereby significantly promoting the initial Volmer step of HER to generate the reactive hydrogen atoms. Moreover, the porous (Co, Ni)2 P (i.e., Co2 P and Ni2 P) nanosheets provide enough active sites for adsorption and recombination of reactive hydrogen atoms to produce hydrogen gas. The catalytic synergy of (Co, Ni)2 P and Ov coupled with the hierarchically porous structure renders the porous (Co, Ni)2 P@0.1TiO2 nanosheet arrays excellent electrocatalysts for HER, showing a small overpotential (92 mV) to yield a current density of 10 mA cm-2 , a small Tafel slope (49 mV dec-1 ), and an outstanding stability. This work demonstrates a surface decoration route for enhancing the activity of nonprecious metal-based electrocatalysts for HER.

18.
ChemSusChem ; 11(22): 3905-3910, 2018 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-30118578

RESUMEN

Numerous catalysts have been successfully introduced for CO2 fixation in aqueous or organic systems. However, a single catalyst showing activity in both solvent types is still rare, to the best of our knowledge. We developed a core-shell-structured AgNW/NC700 composite using a Ag nanowire (NW) core encapsulated by a N-doped carbon (NC) shell at 700 °C. Through control experiments and density functional theory calculations, it was confirmed that Ag nanowires acted as the active sites for CO2 fixation and the uniformly coating of N-doped carbon created a CO2 -rich environment around the Ag nanowires, which could significantly improve the catalytic activity of Ag nanowires for electrochemical CO2 fixation. Under mild conditions, up to 96 % faradaic efficiency of CO, 95 % yield of Ibuprofen and 92 % yield of propylene carbonate could be obtained in the electrochemical CO2 direct reduction, carboxylation and cycloaddition, respectively, using the same AgNWs/NC700 catalyst. These results might provide an alternative strategy for efficient electrochemical fixation of CO2 .

19.
Chem Commun (Camb) ; 54(33): 4108-4111, 2018 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-29537037

RESUMEN

A novel Pt-NP@NCNF@CC composite was prepared by the electrospinning technique. It is a highly efficient and binder-free catalyst for the direct reduction and carboxylation of CO2 with halides. Formate with 91% Faradaic efficiency and 2-phenylpropionic acid with 99% yield could be obtained, respectively. Moreover, this catalyst has excellent stability and reusability.

20.
Nanoscale Res Lett ; 11(1): 204, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27083585

RESUMEN

Graphene coating is receiving discernable attention to overcome the significant challenges associated with large volume changes and poor conductivity of silicon nanoparticles as anodes for lithium-ion batteries. In this work, a tremella-like nanostructure of silicon@void@graphene-like nanosheets (Si@void@G) composite was successfully synthesized and employed as a high-performance anode material with high capacity, cycling stability, and rate capacity. The Si nanoparticles were first coated with a sacrificial SiO2 layer; then, the nitrogen-doped (N-doped) graphene-like nanosheets were formed on the surface of Si@SiO2 through a one-step carbon-thermal method, and the SiO2 layer was removed subsequently to obtain the Si@void@G composite. The performance improvement is mainly attributed to the good conductivity of N-doped graphene-like nanosheets and the unique design of tremella nanostructure, which provides a void space to allow for the Si nanoparticles expanding upon lithiation. The resulting electrode delivers a capacity of 1497.3 mAh g(-1) at the current density of 0.2 A g(-1) after 100 cycles.

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