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1.
Int J Genomics ; 2024: 3375173, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39105136

RESUMEN

The seeds of Camellia oleifera produce high amount of oil, which can be broadly used in the fields of food, industry, and medicine. However, the molecular regulation mechanisms of seed development and oil accumulation in C. oleifera are unclear. In this study, evolutionary and expression analyses of the MADS-box gene family were performed across the C. oleifera genome for the first time. A total of 86 MADS-box genes (ColMADS) were identified, including 60 M-type and 26 MIKC members. More gene duplication events occurred in M-type subfamily (6) than that in MIKC subfamily (2), and SEP-like genes were lost from the MIKCC clade. Furthermore, 8, 15, and 17 differentially expressed ColMADS genes (DEGs) were detected between three developmental stages of seed (S1/S2, S2/S3, and S1/S3), respectively. Among these DEGs, the STK-like ColMADS12 and TT16-like ColMADS17 were highly expressed during the seed formation (S1 and S2), agreeing with their predicted functions to positively regulate the seed organogenesis and oil accumulation. While ColMADS57 and ColMADS07 showed increasing expression level with the seed maturation (S2 and S3), conforming to their potential roles in promoting the seed ripening. In all, these results revealed a critical role of MADS-box genes in the C. oleifera seed development and oil accumulation, which will contribute to the future molecular breeding of C. oleifera.

2.
Angew Chem Int Ed Engl ; : e202408474, 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39034287

RESUMEN

Transition metal oxides (TMOs) are recognized as high-efficiency electrocatalyst systems for restraining the shuttle effect in lithium-sulfur (Li-S) batteries, owing to their robust adsorption capabilities for polysulfides. However, the sluggish catalytic conversion of Li2S redox and severe passivation effect of TMOs exacerbate polysulfide shuttling and reduce the cyclability of Li-S batteries, which significantly hinders the development of TMOs electrocatalysts. Here, through the anion-cation doping approach, dual incorporation of phosphorus and molybdenum into MnO2 (P,Mo-MnO2) was engineered, demonstrating effective mitigation of the passivation effect and allowing for the simultaneous immobilization of polysulfides and rapid redox kinetics of Li2S. Both experimental and theoretical investigations reveal the pivotal role of dopants in fine-tuning the d-band center and optimizing the electronic structure of MnO2. Furthermore, this well-designed configuration processes catalytic selectivity. Specifically, P-doping expedites rapid Li2S nucleation kinetics by minimizing reaction-free energy, while Mo-doping facilitates robust Li2S dissolution kinetics by mitigating decomposition barriers. This dual-doping approach equips P,Mo-MnO2 with robust bi-directional catalytic activity, effectively overcoming passivation effect and suppressing the notorious shuttle effect. Consequently, Li-S batteries incorporating P,Mo-MnO2-based separators demonstrate favorable performance than pristine TMOs. This design offers rational viewpoint for the development of catalytic materials with superior bi-directional sulfur electrocatalytic in Li-S batteries.

3.
Small ; : e2402527, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888122

RESUMEN

Aqueous zinc-iodine batteries are promising candidates for large-scale energy storage due to their high energy density and low cost. However, their development is hindered by several drawbacks, including zinc dendrites, anode corrosion, and the shuttle of polyiodides. Here, the design of 2D-shaped tungsten boride nanosheets with abundant borophene subunits-based active sites is reported to guide the (002) plane-dominated deposition of zinc while suppressing side reactions, which facilitates interfacial nucleation and uniform growth of zinc. Meanwhile, the interfacial d-band orbits of tungsten sites can further enhance the anchoring of polyiodides on the surface, to promote the electrocatalytic redox conversion of iodine. The resulting tungsten boride-based I2 cathodes in zinc-iodine cells exhibit impressive cyclic stability after 5000 cycles at 50 C, which accelerates the practical applications of zinc-iodine batteries.

4.
Adv Sci (Weinh) ; 11(20): e2307995, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38468444

RESUMEN

Heterogeneous structures and doping strategies have been intensively used to manipulate the catalytic conversion of polysulfides to enhance reaction kinetics and suppress the shuttle effect in lithium-sulfur (Li-S) batteries. However, understanding how to select suitable strategies for engineering the electronic structure of polar catalysts is lacking. Here, a comparative investigation between heterogeneous structures and doping strategies is conducted to assess their impact on the modulation of the electronic structures and their effectiveness in catalyzing the conversion of polysulfides. These findings reveal that Co0.125Zn0.875Se, with metal-cation dopants, exhibits superior performance compared to CoSe2/ZnSe heterogeneous structures. The incorporation of low Co2+ dopants induces the subtle lattice strain in Co0.125Zn0.875Se, resulting in the increased exposure of active sites. As a result, Co0.125Zn0.875Se demonstrates enhanced electron accumulation on surface Se sites, improved charge carrier mobility, and optimized both p-band and d-band centers. The Li-S cells employing Co0.125Zn0.875Se catalyst demonstrate significantly improved capacity (1261.3 mAh g-1 at 0.5 C) and cycle stability (0.048% capacity delay rate within 1000 cycles at 2 C). This study provides valuable guidance for the modulation of the electronic structure of typical polar catalysts, serving as a design directive to tailor the catalytic activity of advanced Li-S catalysts.

5.
ACS Nano ; 18(12): 8839-8852, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38465917

RESUMEN

Catalytic conversion of polysulfides emerges as a promising approach to improve the kinetics and mitigate polysulfide shuttling in lithium-sulfur (Li-S) batteries, especially under conditions of high sulfur loading and lean electrolyte. Herein, we present a separator architecture that incorporates double-terminal binding (DTB) sites within a nitrogen-doped carbon framework, consisting of polar Co0.85Se and Co clusters (Co/Co0.85Se@NC), to enhance the durability of Li-S batteries. The uniformly dispersed clusters of polar Co0.85Se and Co offer abundant active sites for lithium polysulfides (LiPSs), enabling efficient LiPS conversion while also serving as anchors through a combination of chemical interactions. Density functional theory calculations, along with in situ Raman and X-ray diffraction characterizations, reveal that the DTB effect strengthens the binding energy to polysulfides and lowers the energy barriers of polysulfide redox reactions. Li-S batteries utilizing the Co/Co0.85Se@NC-modified separator demonstrate exceptional cycling stability (0.042% per cycle over 1000 cycles at 2 C) and rate capability (849 mAh g-1 at 3 C), as well as deliver an impressive areal capacity of 10.0 mAh cm-2 even in challenging conditions with a high sulfur loading (10.7 mg cm-2) and lean electrolyte environments (5.8 µL mg-1). The DTB site strategy offers valuable insights into the development of high-performance Li-S batteries.

6.
Mitochondrial DNA B Resour ; 5(1): 422-423, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33366584

RESUMEN

Aquilaria sinensis is one of the most important agarwood-producing trees but critically endangered at present. In this study, we produced the complete chloroplast (cp) genome of A. sinensis via genome survey analysis. The assembled genome is 174,914 base-pairs (bp) in length, with one large single-copy region of 87,361 bp and one small single-copy region of 3347 bp separated by two inverted repeats of 42,103 bp. The genome contains a total of 142 genes, including 96 protein-coding genes, 8 rRNAs, and 38 tRNAs. The phylogenomic tree strongly supports Aquilaria as a monophyly and A. sinensis sister to A. yunnanensis.

7.
Adv Mater ; 32(7): e1906357, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31880000

RESUMEN

Lithium-sulfur (Li-S) batteries are considered to be one of the most promising candidate systems for next-generation electrochemical energy storage. The major challenge of this system is the polysulfide shuttle, which results in poor cycling efficiency. In this work, a highly N-doped carbon/graphene (NC/G) sheet is designed as a sulfur host, which combines the merits of abundant N active sites and high electrical conductivity to achieve in situ anchoring-conversion of lithium polysulfides (LiPSs). Such a host not only has strong binding with LiPSs but also promotes redox kinetics, which are revealed by both experimental investigations and theoretical studies. The sulfur cathode based on the NC/G host exhibits a high initial capacity of 1380 mA h g-1 and a superior cycle stability with a low capacity decay of 0.037% per cycle within 500 cycles at 2 C. Steady areal capacity with a high sulfur loading (5.6 mg cm-2 ) is also attained even without the addition of LiNO3 in the electrolyte. This work proposes and illustrates the importance of in situ anchoring-conversion of LiPSs, offering a new strategy to design multifunctional sulfur hosts for high-performance Li-S batteries.

8.
Chem Commun (Camb) ; 56(5): 786-789, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31845676

RESUMEN

Lithium-sulfur batteries are one of the most promising candidates for next-generation energy storage systems. The major challenge hindering their commercialization is the polysulfide shuttle effect, which causes a series of problems including the loss of active materials, corrosion of the lithium anode, low coulombic efficiency, and poor cycling performance. In this work, we develop a mesoporous silica-based cathode for efficient trapping of lithium polysulfides (LiPSs). This cathode material consists of mesoporous silica (HMS), highly dispersed NiO nanoparticles embedded in the silica structure, and a conductive polymer (polypyrrole-ppy) prepared by in situ polymerization. We employ the concept of both the physical and chemical entrapment of LiPSs, i.e., physically trapping LiPSs by spatial confinement of LiPSs in the silica porous structure and physical adsorption of LiPSs by the silica surface, and chemically binding LiPSs by highly dispersed NiO nanoparticles in the silica structure. The NiO/silica/ppy/S cathode exhibits good cycling stability and maintains over 700 mA h g-1 after 300 cycles. As far as we know, this is the first time that mesoporous silica has been directly employed as a sulfur host material, rather than an additive. The present study opens up a window for nanoporous silica to be employed as the sulfur host.

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