Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Langmuir ; 40(36): 18896-18905, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39192730

RESUMEN

Constructing a heterostructure is regarded as one of the most favorable approaches to attaining the separation ability of photogenerated carriers and strengthening photocatalysis efficiency. In this study, a CdS/Bi2MoO6 type-II heterostructure was constructed through a hydrothermal technique. The photocatalytic test result shows that the degradation efficiency of rhodamine B (RhB) and tetracycline (TC) over CS/BMO-1 was 100 and 92% under visible light, respectively, which is the highest compared to other samples. The exceptional photocatalytic efficiency is principally associated with generating an inherent electric field within a type-II heterostructure, effectively restraining the recombination of photogenerated electron hole pairs. The intermediate products during the photocatalytic degradation of RhB and TC were identified through liquid chromatography-mass spectrometry, and the hypotheses were formulated regarding the corresponding photodegradation mechanisms. Furthermore, the outcomes of capture tests exhibited that the primary active species were •O2- and h+, and a mechanism of the photocatalytic degradation procedure has been proposed.

2.
Front Neurosci ; 18: 1181670, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38737099

RESUMEN

Given its high morbidity, disability, and mortality rates, ischemic stroke (IS) is a severe disease posing a substantial public health threat. Although early thrombolytic therapy is effective in IS treatment, the limited time frame for its administration presents a formidable challenge. Upon occurrence, IS triggers an ischemic cascade response, inducing the brain to generate endogenous protective mechanisms against excitotoxicity and inflammation, among other pathological processes. Stroke patients often experience limited recovery stages. As a result, activating their innate self-protective capacity [endogenous brain protection (EBP)] is essential for neurological function recovery. Acupuncture has exhibited clinical efficacy in cerebral ischemic stroke (CIS) treatment by promoting the human body's self-preservation and "Zheng Qi" (a term in traditional Chinese medicine (TCM) describing positive capabilities such as self-immunity, self-recovery, and disease prevention). According to research, acupuncture can modulate astrocyte activity, decrease oxidative stress (OS), and protect neurons by inhibiting excitotoxicity, inflammation, and apoptosis via activating endogenous protective mechanisms within the brain. Furthermore, acupuncture was found to modulate microglia transformation, thereby reducing inflammation and autoimmune responses, as well as promoting blood flow restoration by regulating the vasculature or the blood-brain barrier (BBB). However, the precise mechanism underlying these processes remains unclear. Consequently, this review aims to shed light on the potential acupuncture-induced endogenous neuroprotective mechanisms by critically examining experimental evidence on the preventive and therapeutic effects exerted by acupuncture on CIS. This review offers a theoretical foundation for acupuncture-based stroke treatment.

3.
Zhen Ci Yan Jiu ; 49(1): 71-78, 2024 Jan 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38239141

RESUMEN

Acupuncture has a positive effect in the treatment of ischemic stroke (IS). A number of studies have confirmed that the role of acupuncture in the treatment of IS, which is closely related to its functions of regulating mitochondrial functions. In the present article, we review the mechanisms of acupuncture underlying improvement of mitochondria in the treatment of IS from 4 aspects: 1) protecting mitochondrial structure integrity, 2) regulative effect on mitochondrial functional activities, including regulating energy metabolism, reducing oxidative stress, suppressing calcium overload, and regulating mitochondrial membrane potential changes, 3) regulating mitochondrial quality control system, including promoting mitochondrial biosynthesis, regulating mitochondrial dynamics and apoptosis, and 4) regula-ting mitochondria-related apoptosis pathways. All of these may provide a theoretical basis for acupuncture in the treatment of IS and a reference for further research.


Asunto(s)
Terapia por Acupuntura , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Neuronas/metabolismo , Estrés Oxidativo , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/terapia
4.
Small ; 19(36): e2301166, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37140076

RESUMEN

Li metal anode has been recognized as the most promising anode for its high theoretical capacity and low reduction potential. But its large-scale commercialization is hampered because of the infinite volume expansion, severe side reactions, and uncontrollable dendrite formation. Herein, the self-supporting porous lithium foam anode is obtained by a melt foaming method. The adjustable interpenetrating pore structure and dense Li3 N protective layer coating on the inner surface enable the lithium foam anode with great tolerance to electrode volume variation, parasitic reaction, and dendritic growth during cycling. Full cell using high areal capacity (4.0 mAh cm-2 ) LiNi0.8Co0.1Mn0.1 (NCM811) cathode with the N/P ratio of 2 and E/C ratio of 3 g Ah-1 can stably operate for 200 times with 80% capacity retention. The corresponding pouch cell has <3% pressure fluctuation per cycle and almost zero pressure accumulation.

5.
Water Res ; 226: 119199, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36244145

RESUMEN

When allocating water resources, stakeholders (such as water departments, agricultural sector actors, and farmers) aim to maximize their benefits. This leads to conflicts between water savings, food security, and profit growth, causing major challenges for water managers. A hydro-economic model was developed to alleviate groundwater sustainability, food security, and economic growth (GFE) conflicts through crop pattern optimization. This model combines groundwater, agronomic, and economic sub-models to simulate spatiotemporal variations in groundwater level, irrigation requirement, crop production, and net profit. The NSGA-II algorithm was used to maximize net profits while minimizing groundwater extraction and food reduction through crop pattern optimization in irrigation areas and under crop production constraints. Then, using the Baoding Plain as the study area, three scenarios with no external water supply and nine scenarios with an external water supply of 0.3, 0.6, and 0.9 km3/y were designed. The present crop pattern caused a groundwater decline of 0.32 m/y and an overdraft of 0.61 km3/y. The three scenarios without external water supply showed different options for maximizing net profit, minimizing groundwater extraction, and minimizing food reduction without affecting food production, food self-sufficiency or groundwater sustainability. All three scenarios cannot simultaneously satisfy the GFE target. With an external water supply of 0.3 km3/y, only one scenario met the GFE target; with that of 0.6 km3/y, all scenarios met the GFE target; and with that of 0.9 km3/y, groundwater levels increased, profits overflowed, and food overproduction occurred.


Asunto(s)
Agua Subterránea , Recursos Hídricos , Abastecimiento de Agua , Agricultura , Modelos Económicos , Agua
6.
Nanoscale ; 13(23): 10320-10328, 2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-33988212

RESUMEN

The shuttle effect derived from the dissolution of lithium polysulfides (LIPs) seriously hinders commercialization of lithium-sulfur (Li-S) batteries. Hence, we skillfully designed 1D cowpea-like CNTs@Bi composites with a double adsorption structure, where the bismuth nanoparticles/nanorods are encapsulated in the cavities of CNTs, avoiding the aggregation of bismuth nanoparticles during cycling and improving the conductivity of the electrode. Meanwhile, the sulfur was evenly distributed on the surface of bismuth nanoparticles/nanorods, ensuring effective catalytic activity and displaying high sulfur loading. Under the synergetic effects of the physical detention of abundant pores and chemical adsorption of bismuth, LIPs can be minimised, effectively curbing the shuttle effect. Benefiting from the above advantages, the CNTs@Bi/S cathodes exhibit a high capacity of 1352 mA h g-1, long cycling lifespan (708 mA h g-1 after 200 cycles at 1 C) and excellent coulombic efficiency. As the anodes of lithium-ion batteries (LIBs), the CNTs@Bi composites also show excellent performance due to the encapsulated structure to accommodate the serious volume change. This work offers an innovative strategy for improving the performances of the Li-S batteries and LIBs.

7.
Angew Chem Int Ed Engl ; 59(17): 6665-6674, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-31587466

RESUMEN

Electroplating has been studied for centuries, not only in the laboratory but also in industry for machinery, electronics, automobile, aviation, and other fields. The lithium-metal anode is the Holy Grail electrode because of its high energy density. But the recyclability of lithium-metal batteries remains quite challenging. The essence of both conventional electroplating and lithium plating is the same, reduction of metal cations. Thus, industrial electroplating knowledge can be applied to revisit the electroplating process for lithium-metal anodes. In conventional electroplating, some strategies like using additives, modifying substrates, applying pulse current, and agitating electrolyte have been explored to suppress dendrite growth. These methods are also effective in lithium-metal anodes. Inspired by that, we revisit the fundamental electroplating theory for lithium-metal anodes in this Minireview, mainly drawing attention to the theory of electroplating thermodynamics and kinetics. Analysis of essential differences between traditional electroplating and plating/stripping of lithium-metal anodes is also presented. Thus, industrial electroplating knowledge can be applied to the electroplating process of lithium-metal anodes to improve commercial lithium-metal batteries and the study of lithium plating/stripping can further enrich the classical electroplating technique.

8.
Angew Chem Int Ed Engl ; 58(19): 6200-6206, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-30715775

RESUMEN

Progress in lithium-metal batteries is severely hindered by lithium dendrite growth. Lithium is soft with a mechanical modulus as low as that of polymers. Herein we suppress lithium dendrites by forming soft-hard organic-inorganic lamella reminiscent of the natural sea-shell material nacres. We use lithium as the soft segment and colloidal vermiculite sheets as the hard inorganic constituent. The vermiculite sheets are highly negatively charged so can absorb Li+ then be co-deposited with lithium, flattening the lithium growth which remains dendrite-free over hundreds of cycles. After Li+ ions absorbed on the vermiculite are transferred to the lithium substrate, the vermiculite sheets become negative charged again and move away from the substrate along the electric field, allowing them to absorb new Li+ and shuttling to and from the substrate. Long term cycling of full cells using the nacre-mimetic lithium-metal anodes is also demonstrated.

9.
Small ; 14(19): e1800133, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29638037

RESUMEN

Nanostructured carbon materials play essential roles in electrochemical energy storage devices. However, scalable production of high surface area carbon with a cost-effective process while controlling the morphology is challenging. Herein, a one-step procedure to produce carbon sheets with very high specific surface area up to 3411 m2 g-1 by direct pyrolysis of dipotassium ethylene diamine tetraacetate is reported. Unlike that of biomass-pyrolyzed carbons, the surface area of prepared carbon sheets is not sensitive to pyrolysis conditions (e.g., heating temperature and time), which makes the production robust and scalable. Moreover, the pore structure is stable against posttreatments, including solvent washing, which are detrimental to that of graphene-based soft sheet assemblies. When used as supercapacitor electrodes, the ultrahigh surface area carbon sheets (HSACS) show a high specific capacitance of 268 F g-1 at 5 mV s-1 , and retain 70% of the capacitance at 100 times higher scan rate in 6 m KOH aqueous electrolyte. Furthermore, the HSACS also exhibit a high specific capacitance of 266 F g-1 within a 1.6 V symmetric supercapacitor potential window in 2 m Li2 SO4 aqueous electrolyte. The symmetric supercapacitor delivers a maximum specific energy of 23.6 W h kg-1 and high power density of 6.4 kW kg-1 .

10.
Chemistry ; 22(7): 2339-44, 2016 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-26751009

RESUMEN

Nitrogen-doped mesoporous hollow carbon spheres (NHCS) consisting of hybridized amorphous and graphitic carbon were synthesized by chemical vapor deposition with pitch as raw material. Treatment with HNO3 vapor was performed to incorporate oxygen-containing groups on NHCS, and the resulting NHCS-O showed excellent rate capacity, high reversible capacity, and excellent cycling stability when tested as the anode material in lithium-ion batteries. The NHCS-O electrode maintained a reversible specific capacity of 616 mAh g(-1) after 250 cycles at a current rate of 500 mA g(-1) , which is an increase of 113 % compared to the pristine hollow carbon spheres. In addition, the NHCS-O electrode exhibited a reversible capacity of 503 mAh g(-1) at a high current density of 1.5 A g(-1) . The superior electrochemical performance of NHCS-O can be attributed to the hybrid structure, high N and O contents, and rich surface defects.

11.
Vet Parasitol ; 206(3-4): 297-303, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25458119

RESUMEN

Artemisinin (ART) is a sesquiterpene lactone isolated from Artemesia annua L., and well-known for the antimalarial treatment. Recently many reports show the effectiveness of ART in the control of poultry coccidiosis, but the mechanism remains unclear. In this study, we found that ART could effectively improve the pathological alterations in chicken ceca infected by E. tenella with decreased number of second generation merozoites (SGM). In addition, ART significantly reduced mitochondrial membrane potential by 47.4% and notably increased apoptotic rate by 61.9% in SGM. Morphological analysis showed that SGM with ART treatment represented some apoptotic features such as the condensability of chromatin, increase of cytoplasmic density and the marginalization of heterochromatin. We also found that ART treatment significantly increased caspase-3 activity whereas reduced Bcl-2 activity in cecum tissues compared with the infection group by immunohistochemical analysis. These results suggest the anticoccidial effects of ART are closely related to facilitate apoptosis in both merozoites and the infected host cells. This study makes a better understanding of ART against poultry coccidiosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Pollos/parasitología , Coccidiosis/tratamiento farmacológico , Eimeria tenella/efectos de los fármacos , Enfermedades de las Aves de Corral/tratamiento farmacológico , Animales , Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Ciego/patología , Coccidiosis/parasitología , Coccidiostáticos/uso terapéutico , Femenino , Masculino , Merozoítos/efectos de los fármacos , Enfermedades de las Aves de Corral/parasitología , Enfermedades de las Aves de Corral/patología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA