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1.
ChemSusChem ; 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33258550

RESUMO

Lithium-sulfur battery (LSB) has become one of the most promising candidates for next-generation energy storage systems owing to its high theoretical energy density, environmental friendliness, and cost-effectiveness. However, its real-word applications are seriously restricted by its undesirable shuttle effect and lithium (Li) dendrite formation. In essence, uncontrollable anion transport is a key factor that causes both polysulfide shuttling and dendrite formation, which creates the possibility of simultaneously addressing the two critical issues in LSBs. An effective strategy to control anion transport is the construction of cation-selective separators. A significant progress has been achieved in the inhibition of the shuttle effect, whereas addressing the problem of Li dendrite formation by utilizing a cation-selective separator is still underway. From this viewpoint, this review analyzes the critical issues with regard to the shuttle effect and Li dendrite formation caused by uncontrollable anion transport, based on which the roles and advantages of cation-selective separators toward high-performance LSBs are presented. According to the separator construction principle, the latest advances and progress in cation-selective separators in inhibiting the shuttle effect and Li dendrite formation are reviewed in detail. Finally, some challenges and prospects are proposed for the future development of cation-selective separators. This review is anticipated to provide a new perspective for simultaneously addressing the two critical issues in LSBs.

2.
Bioorg Chem ; 103: 104230, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32916540

RESUMO

Inspired with an increasing environmental awareness, we performed an eco-friendly amenable process for the synthesis of silver nanoparticles (AgNPs) using the catkins of Piper longum as an alternative approach with the existing methods of using plant extracts. The fabrication of nanoparticles occurred within 10 min. This was initially observed by colour change of the solution. UV-visible spectroscopic studies (UV-Vis) were performed for further confirmation. The analysis elucidated that the surface plasmon resonance (SPR) was specifically corresponding to AgNPs. Fourier transform infrared spectrophotometry (FTIR) studies indicated that polyphenols could possibly be the encapsulating agents. The size and shape of the nanoparticles was analysed using Transmission electron microscopy (TEM). The nanoparticles were predominant spheres ranging between 10 and 42 nm at two different scales. The formation of elemental silver was confirmed further by X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRD). GC-MS analysis was used to identify the possible encapsulates on the nanoparticles. The antibacterial effect of the biosynthesized AgNPs was tested against two gram-positive (Bacillus cereus and Staphylococcus aureus), and five gram-negative (Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella typhi) bacteria. Outcomes of the study suggest that these pathogens were susceptible to the AgNPs. This is the first ever international report on correlating the antibacterial effect of silver nanoparticles using mathematical modelling with a conventional antimicrobial assay. The results indicate that nanoparticles of silver synthesized using catkin extract of P. longum can be exploited towards the development of potential antibacterial agents.

3.
Nanoscale ; 12(30): 15923-15943, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32510069

RESUMO

Electrochemical power sources, as one of the most promising energy storage and conversion technologies, provide great opportunities for developing high energy density electrochemical devices and portable electronics. However, uncontrolled ionic transport in electrochemical energy conversion, typically undesired anion transfer, usually causes some issues degrading the performance of energy storage devices. Nanochannels offer an effective strategy to solve the ionic transport problems for boosting electrochemical energy storage and conversion. In this review, the advantages of nanochannels for electrochemical energy storage and conversion and the construction principle of nanochannels are introduced, including ion selectivity and ultrafast ion transmission of nanochannels, which are considered as two critical factors to achieve highly efficient energy conversion. Recent advances in applications of nanochannels in lithium secondary batteries (LSBs), electrokinetic energy conversion systems and concentration cells are summarized in detail. Nanochannels exist in the above systems in two typical forms: functional separator and electrode protective layer. Current research on nanochannel-based LSBs is still at the early stage, and deeper and broader applications are expected in the future. Finally, the remaining challenges of nanochannel fabrication, performance improvement, and intelligent construction are presented. It is envisioned that this paper will provide new insights for developing high-performance and versatile energy storage electronics based on nanochannels.

4.
Pregnancy Hypertens ; 21: 132-138, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32512528

RESUMO

Preeclampsia (PE) is one type of hypertension during pregnancy that seriously threatens maternal and infant health. Trophoblast dysfunction, such as decreased proliferation and migration, is closely related to the occurrence and development of PE. MicroRNAs (miRNAs) have been proven to play an important role in many diseases, including PE. miR-384 was reported to play a regulatory role in promoting cell apoptosis and inhibiting proliferation, migration and invasion in a variety of tumors. Previously, we found that miR-384 is upregulated in the placenta and plasma in the context of PE. In this study, we elucidated the function of miR-384 in the trophoblast cell line HTR-8/SVneo and the trophoblastic tumor cell line JEG-3. Cell proliferation and migration were inhibited by miR-384 overexpression but promoted by miR-384 downregulation. Subsequently, polypyrimidine tract-binding protein 3(PTBP3) was found to be a direct target gene of miR-384. PTBP3 was downregulated in placental tissues from PE patients, and a negative correlation was found between PTBP3 and miR-384. Our results suggest that the miR-384/PTBP3 axis plays an important role in regulating trophoblast function during the progression of PE, and these data provide novel insight into the molecular pathogenesis of this disorder.

5.
Life Sci ; 220: 156-161, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30716338

RESUMO

Magnetic nanoparticles (MNPs) are promising candidates for drug delivery and treatment of various disorders. Toxicity evaluation is a critical point in the development of nanoformulations and therefore, draws considerable attention. Formulations involving individual or combinatorial nanoparticle suspensions might be used for targeted delivery and treatment. This might be a evaluated further for safety related issues considering future medications based on MNPs. Nanoparticle distribution in the body is dependent on its surface characteristics. Size, dose and routes of nanoparticle entry have to be taken into consideration for future assays.


Assuntos
Nanopartículas de Magnetita/toxicidade , Nanopartículas/efeitos adversos , Animais , Sistemas de Liberação de Medicamentos/efeitos adversos , Humanos , Nanopartículas de Magnetita/efeitos adversos , Nanopartículas/toxicidade , Preparações Farmacêuticas
6.
Nanomicro Lett ; 10(1): 1, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30393650

RESUMO

The requirement of energy-storage equipment needs to develop the lithium ion battery (LIB) with high electrochemical performance. The surface modification of commercial LiFePO4 (LFP) by utilizing zeolitic imidazolate frameworks-8 (ZIF-8) offers new possibilities for commercial LFP with high electrochemical performances. In this work, the carbonized ZIF-8 (CZIF-8) was coated on the surface of LFP particles by the in situ growth and carbonization of ZIF-8. Transmission electron microscopy indicates that there is an approximate 10 nm coating layer with metal zinc and graphite-like carbon on the surface of LFP/CZIF-8 sample. The N2 adsorption and desorption isotherm suggests that the coating layer has uniform and simple connecting mesopores. As cathode material, LFP/CZIF-8 cathode-active material delivers a discharge specific capacity of 159.3 mAh g-1 at 0.1C and a discharge specific energy of 141.7 mWh g-1 after 200 cycles at 5.0C (the retention rate is approximate 99%). These results are attributed to the synergy improvement of the conductivity, the lithium ion diffusion coefficient, and the degree of freedom for volume change of LFP/CZIF-8 cathode. This work will contribute to the improvement of the cathode materials of commercial LIB.

7.
Biomed Pharmacother ; 93: 490-497, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28672279

RESUMO

Endoplasmic reticulum stress (ERs) has been regarded as an important cause for the pathogenesis of non-small-cell lung cancer (NSCLC). ß-elemene is an active component in the essential oil extracted from a medicinal herb, Curcuma wenyujin, and has been reported to be effective against non-small-cell lung cancer (NSCLC). However, the potential effect and underlying mechanisms of ß-elemene on regulating ERs to inhibit NSCLC are still unclear. In the present study, A549 cells and Lewis tumor-bearing C57BL/6J mice were established to evaluate this effect. Visualsonics Vevo 2100 Small Animal Dedicated High-frequency Color Ultrasound was performed to observe tumor volume in vivo. 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) was used to evaluate cell vitality of A549 cells. Furthermore, western blotting (WB), immunohistochemistry (IHC) and quantitative reverse transcription polymerase chain reaction (q-PCR) were applied to detect the ERs-related proteins. Flow cytometry was also applied to detect cell apoptosis and assay kit for reactive oxygen species (ROS) generation. Our results showed that ß-elemene inhibited lung cancer tumor growth and cell vitality in a dose- and time-dependent manner. Not only that, ß-elemene could up-regulate ERs-related proteins like PERK, IRE1α, ATF6, ATF4, CHOP and down-regulate the Bcl-2 expression. More importantly, ERs inhibitor 4-PBA, IRE1α inhibitor STF-083010, ATF6 inhibitor Anti-ATF6 and PERK inhibitor GSK2656157 can all reduce the amplitude of protein expression changes and apoptosis rates, then weaken the anti-tumor effect of ß-elemene. Therefore, the present in vivo and in vitro study revealed that the anti-NSCLC effect of ß-elemene is closely related to the activation of ERs through PERK/IRE1α/ATF6 pathway, and this might be beneficial for clinical therapy of NSCLC.


Assuntos
Fator 6 Ativador da Transcrição/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Endorribonucleases/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Sesquiterpenos/farmacologia , eIF-2 Quinase/metabolismo , Células A549 , Animais , Antineoplásicos Fitogênicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos Endogâmicos C57BL , Modelos Biológicos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fator de Transcrição CHOP/metabolismo
8.
Nanomicro Lett ; 9(2): 22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30460318

RESUMO

High-voltage lithium-ion batteries (HVLIBs) are considered as promising devices of energy storage for electric vehicle, hybrid electric vehicle, and other high-power equipment. HVLIBs require their own platform voltages to be higher than 4.5 V on charge. Lithium nickel manganese spinel LiNi0.5Mn1.5O4 (LNMO) cathode is the most promising candidate among the 5 V cathode materials for HVLIBs due to its flat plateau at 4.7 V. However, the degradation of cyclic performance is very serious when LNMO cathode operates over 4.2 V. In this review, we summarize some methods for enhancing the cycling stability of LNMO cathodes in lithium-ion batteries, including doping, cathode surface coating, electrolyte modifying, and other methods. We also discuss the advantages and disadvantages of different methods.

9.
ACS Appl Mater Interfaces ; 6(2): 1106-12, 2014 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-24392810

RESUMO

A new type of three-dimensional (3D) NiO/ultrathin derived graphene (UDG) hybrid on commercial Ni foam (NF) for a binder-free pseudocapacitor electrode is presented. NiO nanoflakes are in situ grown by a chemical bath deposition (CBD) technique on the free-standing 3D UDG/NF scaffold, which is first prepared by a simple nanocasting process consisting of hydrothermal reaction and subsequent thermal transformation. The 3D UDG/NF scaffold with interconnected network affords a high conductivity due to the high graphitization degree and efficiently facilitates the electron transport to NiO. Moreover, the 3D NiO/UDG/NF hybrid allows for a thinner 3D active material layer under the same loading density, which could shorten the diffusion paths of ions. The NiO/UDG/NF hybrid is directly used as a binder-free supercapacitor electrode, which exhibited significantly improved supercapacitor performance compared to the bare CBD prepared NiO/NF electrode.

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