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1.
J Org Chem ; 89(10): 6783-6792, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38661714

RESUMO

Tetrazoles and their derivatives are essential for compound synthesis due to their versatility, effectiveness, stability in air, and cost-efficiency. This has stimulated interest in developing techniques for their production. In this work, four compounds, tetrazolo[1,5-c]pyrimidin-5-amine (1), N-(4-azidopyrimidin-2-yl)nitramide (2), tetrazolo[1,5-c]pyrimidin-5(6H)-one (3), and tetrazolo[1,5-a]pyrimidin-5-amine (4), were obtained from commercially available reagents and straightforward synthetic methodologies. These new compounds were characterized by infrared (IR), 13C, and 1H NMR spectroscopy, differential scanning calorimetry (DSC), and single-crystal X-ray diffraction. The solvent, temperature, and electron-donating group (EDG) factors that were responsible for the steering of azido-tetrazole equilibrium in all compounds were also studied. In addition, the detonation performance of the target compounds was calculated by using heats of formation (HOFs) and crystal densities. Hirshfeld surface analysis was used to examine the intermolecular interactions of the four synthesized compounds. The results show that the excellent properties of 1-4 are triggered by ionic bonds, hydrogen bonds, and π-π stacking interactions, indicating that these compounds have the potential to be used in the development of high-performance energetic materials. Additionally, DFT analysis is in support of experimental results, which proved the effect of different factors that can influence the azido-tetrazole equilibrium in the synthesized pyrimidine derivatives in the solution.

2.
BMC Plant Biol ; 24(1): 334, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664603

RESUMO

BACKGROUND: B-box (BBX) proteins are a type of zinc finger proteins containing one or two B-box domains. They play important roles in development and diverse stress responses of plants, yet their roles in wheat remain unclear. RESULTS: In this study, 96 BBX genes were identified in the wheat genome and classified into five subfamilies. Subcellular localization prediction results showed that 68 TaBBXs were localized in the nucleus. Protein interaction prediction analysis indicated that interaction was one way that these proteins exerted their functions. Promoter analysis indicated that TaBBXs may play important roles in light signal, hormone, and stress responses. qRT-PCR analysis revealed that 14 TaBBXs were highly expressed in seeds compared with other tissues. These were probably involved in seed dormancy and germination, and their expression patterns were investigated during dormancy acquisition and release in the seeds of wheat varieties Jing 411 and Hongmangchun 21, showing significant differences in seed dormancy and germination phenotypes. Subcellular localization analysis confirmed that the three candidates TaBBX2-2 A, TaBBX4-2 A, and TaBBX11-2D were nuclear proteins. Transcriptional self-activation experiments further demonstrated that TaBBX4-2A was transcriptionally active, but TaBBX2-2A and TaBBX11-2D were not. Protein interaction analysis revealed that TaBBX2-2A, TaBBX4-2A, and TaBBX11-2D had no interaction with each other, while TaBBX2-2A and TaBBX11-2D interacted with each other, indicating that TaBBX4-2A may regulate seed dormancy and germination by transcriptional regulation, and TaBBX2-2A and TaBBX11-2D may regulate seed dormancy and germination by forming a homologous complex. CONCLUSIONS: In this study, the wheat BBX gene family was identified and characterized at the genomic level by bioinformatics analysis. These observations provide a theoretical basis for future studies on the functions of BBXs in wheat and other species.


Assuntos
Germinação , Família Multigênica , Dormência de Plantas , Proteínas de Plantas , Triticum , Triticum/genética , Triticum/fisiologia , Dormência de Plantas/genética , Germinação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Simulação por Computador , Filogenia
3.
ACS Appl Mater Interfaces ; 16(5): 5989-5998, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38271587

RESUMO

In recent years, solid electrolytes (SEs) have been developed a lot due to the superior safety of solid-state batteries (SSBs) upon liquid electrolyte-based commercial batteries. Among them, garnet-type Li7La3Zr2O12 (LLZO) is one of the few SEs that is stable to lithium anode with high Li+ conductivity and the feasibility of preparation under ambient air, which makes it a promising candidate for fabricating SSBs. However, high sintering temperature (>1200 °C) prevents its large-scale production, further hindering its application. In this work, the Li5AlO4 sintering aid is proposed to decrease the sintering temperature and modify the grain boundaries of LLZO ceramics. Li5AlO4 generates in situ Li2O atmosphere and molten Li-Al-O compounds at relatively low temperatures to facilitate the gas-liquid-solid material transportation among raw LLZO grains, which decreases the densification temperature over 150 °C and strengthens the grain boundaries against lithium dendrites. As an example, Ta-doped LLZO ceramics without excessive Li sintered with 2 wt % Li5AlO4 at 1050 °C delivered high relative density > 94%, an ionic conductivity of 6.7 × 10-4 S cm-1, and an excellent critical current density (CCD) of 1.5 mA cm-2 at room temperature. In comparison, Ta-doped LLZO with 15% excessive Li sintered at 1200 °C delivered low relative density < 89%, a low ionic conductivity of ∼2 × 10-4 S cm-1, and a poor CCD of 0.5 mA cm-2. Li symmetric cells and Li-LFP full cells fabricated with Li5AlO4-assised ceramics were stably cycled at 0.2 mA cm-2 over 2000 h and at 0.8C over 100 cycles, respectively.

4.
Anal Methods ; 15(42): 5692-5699, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37861716

RESUMO

Colloidal gold immunoassay is the most widely used method in the field of drug detection. However, this method often has poor quantitative identification ability and low analytical sensitivity, which is not suitable for the analysis of hair poisoning ingredients. In order to solve these limitations, we developed an immunochromatographic test strip for simultaneously screening multiple drugs in this study. This hand-held test strip used fluorescent nanoparticles loaded with lanthanide chelates as the signal carrier of fluorescence reading, and conducted quantitative testing of various drugs based on the competitive immune reaction between the analyte and antigen. Under the optimal conditions, the competition curves of morphine (MOP), methamphetamine (MET) and ketamine (KET) were obtained on a single band. The detection limit (LOD) of this analytical method was 100-1000 times lower than that of colloidal gold test strips. The detection limits of MOP, MET and KET were 0.06 ng mL-1, 0.1 ng mL-1 and 1.0 ng mL-1, respectively. No cross-reaction was observed when morphine, methamphetamine and ketamine were tested simultaneously with this method. And 184 hair samples were tested simultaneously, and the detected amount was very close to the results of LC-MS. The immunochromatographic strip showed good stability in repeated tests, and the coefficient of variation was less than 15%. Fluorescence immunochromatography strips and handheld strip readers have the characteristics of portability, speed, ease of operation and high sensitivity, and may become powerful tools for screening drug abuse in hair in forensic medicine.


Assuntos
Ketamina , Elementos da Série dos Lantanídeos , Metanfetamina , Morfina/análise , Limite de Detecção , Metanfetamina/análise , Cromatografia de Afinidade/métodos , Coloide de Ouro/química , Cabelo/química
5.
Chem Commun (Camb) ; 59(87): 13018-13021, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37842776

RESUMO

One of the most common problems with sulfide solid-state electrolytes is weak water stability. We report a re-sintering method to recover the ionic conductivity of argyrodite Li5.4PS4.4Cl1.6 solid-state electrolyte, which has been exposed to moisture for 10 h, from 1.06 to 6.97 mS cm-1.

6.
Bioorg Chem ; 140: 106822, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37666111

RESUMO

Pyrimidine which is an important constituent of the genetic material of deoxyribonucleic acid, is identified with a large number of biological activities. Based on this, pyrimidine-derived Schiff bases (1-6) of hydroxy-1-naphthaldehyde were synthesized by using the condensation method. In addition, the molecular docking studies against topoisomerase II DNA gyrase, human hematopoietic cell kinase, urate oxidase from Aspergillus flavus, and cyclin-dependent kinase 8 to explore the antibacterial, antioxidant, antifungal, and anticancer properties respectively and binding affinities through bioinformatics approaches to determine the interaction among active molecules with the receptor. Hence, the computational docking analyses identified that all synthesized pyrimidine Schiff bases (1-6) are active and exhibited better binding affinities as compared to the standard drugs. Furthermore, all the prepared materials were characterized by using nuclear magnetic resonance, infrared, and elemental analysis. Additionally, the phase-transition and thermal decomposition temperatures were determined by differential scanning calorimetry and thermo-gravimetric analysis measurements. Moreover, the structures of pyrimidine-derived Schiff bases 1, 2, 3, 4, and 5 were also confirmed by the X-ray single-crystal diffraction technique. The pyrimidine-derived Schiff bases 5 possess significant antibacterial, antioxidant, antifungal, and anticancer agent properties which confirms its promising biological activities over standard drugs.


Assuntos
Antifúngicos , Antioxidantes , Humanos , Antifúngicos/farmacologia , Simulação de Acoplamento Molecular , Bases de Schiff/farmacologia , Pirimidinas/farmacologia , Antibacterianos/farmacologia
7.
ACS Appl Mater Interfaces ; 15(30): 36289-36300, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37470362

RESUMO

NASICON-type Li1.3Al0.3Ti1.7(PO4)3 (LATP) has attracted a lot of attention because of its high ionic conductivity and stability to air and moisture. However, the size effect of LATP primary particles on ionic conductivity is ignored. In this study, different sizes of LATP particles are prepared to investigate the morphology, relative density, and ionic conductivity of the LATP solid electrolyte. The influences of particle size and sintering temperature on the microstructure, phase composition, and electrical properties of LATP ceramics were systematically studied. The medium-sized LATP particle (2 µm) presents a great microstructure with a high relative density of over 97%, the highest ionic conductivity of 6.7 × 10-4 S cm-1, and an activation energy of 0.418 eV. The Li-Li symmetric cells and Li-LFP batteries delivering good electrochemical performance were fabricated with highly conductive LATP ceramics. These results make significant strides in elucidating the relationship between the particle sizes of LATP and its electrochemical performance.

8.
Biomed Mater ; 18(4)2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37144422

RESUMO

Increased life expectancy has resulted in an increase in osteoporosis incidence worldwide. The coupling of angiogenesis and osteogenesis is indispensable for bone repair. Although traditional Chinese medicine (TCM) exerts therapeutic effects on osteoporosis, TCM-related scaffolds, which focus on the coupling of angiogenesis and osteogenesis, have not yet been used for the treatment of osteoporotic bone defects.Panax notoginsengsaponin (PNS), the active ingredient ofPanax notoginseng, was added to a poly (L-lactic acid) (PLLA) matrix. Osteopractic total flavone (OTF), the active ingredient ofRhizoma Drynariae, was encapsulated in nano-hydroxyapatite/collagen (nHAC) and added to the PLLA matrix. Magnesium (Mg) particles were added to the PLLA matrix to overcome the bioinert character of PLLA and neutralize the acidic byproducts generated by PLLA. In this OTF-PNS/nHAC/Mg/PLLA scaffold, PNS was released faster than OTF. The control group had an empty bone tunnel; scaffolds containing OTF:PNS = 100:0, 50:50, and 0:100 were used as the treatment groups. Scaffold groups promoted new vessel and bone formation, increased the osteoid tissue, and suppressed the osteoclast activity around osteoporotic bone defects. Scaffold groups upregulated the expression levels of angiogenic and osteogenic proteins. Among these scaffolds, the OTF-PNS (50:50) scaffold exhibited a better capacity for osteogenesis than the OTF-PNS (100:0 and 0:100) scaffolds. Activation of the bone morphogenic protein (BMP)-2/BMP receptor (BMPR)-1A/runt-related transcription factor (RUNX)-2signaling pathway may be a possible mechanism for the promotion of osteogenesis. Our study demonstrated that the OTF-PNS/nHAC/Mg/PLLA scaffold could promote osteogenesis via the coupling of angiogenesis and osteogenesis in osteoporotic rats with bone defects, and activating theBMP-2/BMPR1A/RUNX2signaling pathway may be an osteogenesis-related mechanism. However, further experiments are necessary to facilitate its practical application in the treatment of osteoporotic bone defects.


Assuntos
Osteogênese , Osteoporose , Ratos , Animais , Engenharia Tecidual/métodos , Alicerces Teciduais , Osso e Ossos/metabolismo , Poliésteres/farmacologia , Osteoporose/terapia , Osteoporose/metabolismo
9.
Chem Commun (Camb) ; 59(47): 7220-7223, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37221931

RESUMO

A novel efficient method is proposed to synthesize a large amount of Li5.4PS4.4Cl1.6 precursor in only 5 minutes with a conductivity of 20 mS cm-1 after sintering, which can replace the common ball-milling method. The ASSBs show excellent electrochemical performance with high loading (20 mg cm-2) and great capacity retention (80% after 200 cycles). This is important for the industrial production of sulfide solid electrolytes for fabricating Ah-level ASSBs.


Assuntos
Eletrólitos , Lítio , Condutividade Elétrica , Sulfetos
10.
ACS Appl Mater Interfaces ; 15(16): 20064-20074, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37043701

RESUMO

Lithium-sulfur (Li-S) batteries have shown exceptional theoretical energy densities, making them a promising candidate for next-generation energy storage systems. However, their practical application is limited by several challenging issues, such as uncontrollable Li dendrite growth, sluggish electrochemical kinetics, and the shuttling effect of lithium polysulfides (LiPSs). To overcome these issues, we designed and synthesized hierarchical matrixes on carbon cloth (CC) by using metal-organic frameworks (MOFs). ZnO nanosheet arrays were used as anode hosts (CC-ZnO) to enable stable Li plating and stripping. The symmetric cell with CC-ZnO@Li was demonstrated to have enhanced cycling stability, with a voltage hysteresis of ∼25 mV for over 800 h at 1 mA cm-2 and 1 mAh cm-2. To address the cathode challenges, we developed a multifunctional CC-NC-Co cathode host with physical confinement, chemical anchoring, and excellent electrocatalysis. The full cells with CC-ZnO@Li anodes and CC-NC-Co@S cathodes exhibited excellent electrochemical performance, with long cycling life (0.02% and 0.03% capacity decay per cycle when cycling 900 times at 0.5 C and 600 times at 1 C, respectively) and outstanding rate performance (793 mAh g-1 at 4 C). Additionally, the pouch cell based on the flexible CC-ZnO@Li anode and CC-NC-Co@S cathode showed good stability in different bending states. Overall, our study presents an effective strategy for preparing flexible Li and S hosts with hierarchical structures derived from MOF, which can pave the way for high-performance Li-S batteries.

11.
ACS Appl Mater Interfaces ; 15(4): 5345-5356, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36657037

RESUMO

Solid-state batteries based on a metallic Li anode and nonflammable solid electrolytes (SEs) are anticipated to achieve high energy and power densities with absolute safety. In particular, cubic garnet-type Nb-doped Li7La3Zr2O12 (Nb-LLZO) SEs possess superior ionic conductivity, are feasible to prepare under ambient conditions, have strong thermal stability, and are of low cost. However, the interfacial compatibility with Li metal and Li dendrite hazards still hinder the applications of Nb-LLZO. Herein, a quick and efficient solution was applied to address this issue, generating a nano-Li3PO4 pre-reduction layer from the reaction of H3PO4 with the ion-exchanged passivation layer (Li2CO3/LiOH) on the surface of Nb-LLZO. A lithiophilic, electrically insulating interlayer is in situ created when the Li3PO4 modified layer interacts with molten Li, successfully preventing the reduction of Nb5+. The interlayer, which mostly consists of Li3P and Li3PO4, also has a high shear modulus and relatively high Li+ conductivity, which effectively inhibit the growth of Li dendrites. The Li|Li3PO4|Nb-LLZO|Li3PO4|Li symmetric cells stably cycled for over 5000 h at 0.05 mA cm-2 and over 1000 h at a high rate of 0.15 mA cm-2 without any short circuits. The LiFePO4 and S/C hybrid solid-state batteries using the modified Nb-LLZO electrolyte also demonstrated good electrochemical performances, confirming the practical application of this interfacial engineering in various solid-state battery systems. This work offers an efficient solution to the instability issue between the Nb-LLZO SE and metallic Li anode.

12.
Bull Cancer ; 109(10): 1007-1016, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35940943

RESUMO

OBJECTIVE: High expression of Holliday Junction-Recognizing Protein (HJURP) has been shown to be a marker of poor prognosis in ovarian cancer. The objective of this study was to investigate the molecular mechanisms of HJURP in ovarian cancer (OC) progression. PROCEDURES: Gene Expression Profiling Interactive Analysis (GEPIA) was used to analyze the gene expression profile. Real-time quantitative PCR (qRT-PCR) was used to detect the expression level and correlation of HJURP and centromere protein-A (CENP-A) in OC tissues and cell lines. CCK-8 assay was used to detect cell proliferation. The expression level of apoptosis-related proteins and cell cycle-related proteins were detected by western blotting. Cell cycle and mitochondrial content were determined by flow cytometry. RESULTS: The results showed that HJURP was up-regulated in OC tissues and cell lines, while the cell proliferation was inhibited after transfecting by si-HJURP. Knockdown of HJURP promoted cell apoptosis. Meanwhile, low-expression of HJURP could down-regulate cell replication cycle-related proteins (Cyclin-dependent kinase 2, cyclinD1 and Cyclin-dependent kinase 4) and make cell replication stay in the S phase. Moreover, further studies showed that HJURP was positively correlated with CENP-A in OC tissues. Finally, the rescue experiment further verified that HJURP targeted regulation of CENP-A in OC. CONCLUSIONS: The study indicated that HJURP plays a significant role in OC and could target CENP-A to regulate OC cell growth. These findings provide a clue to the diagnosis and treatment of OC.


Assuntos
Proteína Centromérica A , Centrômero , Proteínas Cromossômicas não Histona , Proteínas de Ligação a DNA , Neoplasias Ovarianas , Linhagem Celular Tumoral , Proliferação de Células , Centrômero/metabolismo , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , DNA Cruciforme , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Neoplasias Ovarianas/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-35839326

RESUMO

Li7La3Zr2O12 (LLZO) is one of the most promising candidate solid electrolytes for high-safety solid-state batteries. However, similar to other solid electrolytes containing volatile components during high-temperature sintering, the preparation of densified LLZO with high conductivity is challenging involving the complicated gas-liquid-solid sintering mechanism. Further attention on establishing low-cost laborastory-scale preparation craft platform of LLZO ceramic is also required. This work demonstrates a "pellet on gravel" sintering strategy, which is performed in a MgO crucible and box furnace under ambient air without any special equipment or expensive consumables. In addition, the competition between lithium loss from the sintering system and internal grain densification is critically studied, whereas the influences of particle surface energy, Li-loss amount, and initial excess Li2O amount are uncovered. Based on the sintering behavior and mechanism, optimized craft platform for preparing dense LLZO solid electrolytes including mixing, calcination, particle tailoring and sintering is provided. Finally, exemplary Ta-doped LLZO pellets with 2 wt % La2Zr2O7 additives sintered at 1260-1320 °C for 20 min deliver Li+ conductivities of ∼9 × 10-4 S cm-1 at 25 °C, relative densities of >96%, and a dense cross-sectional microstructure. As a practical demonstration, LLZO solid electrolyte with optimized performance is applied in both Li-Li symmetric cells and Li-S batteries. This work sheds light on the practical production of high-quality LLZO ceramics and provides inspiration for sintering ceramics containing volatile compounds.

14.
ACS Appl Mater Interfaces ; 14(25): 28873-28881, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35714059

RESUMO

Improving the electrochemical kinetics and the intrinsic poor conductivity of transition metal dichalcogenide (TMD) electrodes is meaningful for developing next-generation energy storage systems. As one of the most promising TMD anode materials, ReS2 shows attractive performance in potassium-ion batteries (PIBs). To overcome the poor kinetic ion diffusion and limited cycling stability of the ReS2-based electrode, herein, the interlayer distance expanding strategy was employed, and reduced graphene oxide (rGO) was introduced into ReS2. Few-layered ReS2 nanosheets were grown on the surface of the rGO with expanded interlayer distance. The prepared ReS2 nanosheets show an expanded distance (∼0.77 nm). The synthesized EI-ReS2@rGO composites were used in PIBs as anode materials. The K-ion storage mechanism of the ReS2-based anode was investigated by in situ X-ray diffraction (XRD) technology, which shows the intercalation and conversion types. The EI-ReS2@rGO nanocomposites show high specific capacities of 432.5, 316.5, and 241 mAh g-1 under 0.05, 0.2, and 1.0 A g-1 current densities and exhibit excellent reversibility at 1.0 A g-1. Overall, this strategy, which finely tunes the local chemistry and orbital hybridization for high-performance PIBs, will open up a new field for other materials.

15.
Front Plant Sci ; 13: 870586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35620700

RESUMO

Wheat is one of the most widely cultivated food crops worldwide, and the safe production of wheat is essential to ensure food security. Soil salinization and drought have severely affected the yield and quality of wheat. Valine-glutamine genes play important roles in abiotic stress response. This study assessed the effect of the gene TaVQ14 on drought and salt stresses resistance. Sequence analysis showed that TaVQ14 encoded a basic unstable hydrophobic protein with 262 amino acids. Subcellular localization showed that TaVQ14 was localized in the nucleus. TaVQ14 was upregulated in wheat seeds under drought and salt stress. Under NaCl and mannitol treatments, the percentage of seed germination was higher in Arabidopsis lines overexpressing TaVQ14 than in wild-type lines, whereas the germination rate was significantly lower in plants with a mutation in the atvq15 gene (a TaVQ14 homolog) than in WT controls, suggesting that TaVQ14 increases resistance to salt and drought stress in Arabidopsis seeds. Moreover, under salt and drought stress, Arabidopsis lines overexpressing TaVQ14 had higher catalase, superoxide dismutase, and proline levels and lower malondialdehyde concentrations than WT controls, suggesting that TaVQ14 improves salt and drought resistance in Arabidopsis by scavenging reactive oxygen species. Expression analysis showed that several genes responsive to salt and drought stress were upregulated in Arabidopsis plants overexpressing TaVQ14. Particularly, salt treatment increased the expression of AtCDPK2 in these plants. Moreover, salt treatment increased Ca2+ concentrations in plants overexpressing TaVQ14, suggesting that TaVQ14 enhances salt resistance in Arabidopsis seeds through calcium signaling. In summary, this study demonstrated that the heterologous expression of TaVQ14 increases the resistance of Arabidopsis seeds to salt and drought stress.

16.
ACS Appl Mater Interfaces ; 14(22): 25490-25500, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35608938

RESUMO

Nickel-rich layered cathode LiNi0.8Co0.1Mn0.1O2 (NCM811) is the most promising cathode material due to its high specific capacity and lower cost than lithium cobalt oxides. However, NCM811 suffers from structural instability and capacity degradation during charge-discharge cycles. Herein, we report a strategy to construct a conductive network by employing a holistic Ge coating, which interconnects Mg-doped NCM811 particles. Dopant Mg ions, serving as a "pillar" in the Li slab of NCM811, substantially enhance the structural reversibility. The Ge particles are not only coated on the electrode surface but also enter into the electrode pores to form a multidimensional conductive structure, which improves the conductivity of the electrode and slows down the interface side reaction, thus minimizing the irreversible loss of NCM811 upon long cycling. The modified NCM811 electrode delivers a high discharge capacity (∼204 mAh g-1 at 0.1C), excellent rate performance (∼155 mAh g-1 at 10C), and high capacity retention (83% after 200 cycles) even at 4.4 V. Additionally, a cylindrical full battery with graphite/modified NCM811 undergoes 1000 cycles with 86% capacity retention at 2C.

17.
Adv Sci (Weinh) ; 9(17): e2105538, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35415972

RESUMO

Lithium-sulfur (Li-S) batteries have attracted considerable attention over the last two decades because of a high energy density and low cost. However, the wide application of Li-S batteries has been severely impeded due to the poor electrical conductivity of S, shuttling effect of soluble lithium polysulfides (LiPSs), and sluggish redox kinetics of S species, especially under high S loading. To address all these issues, a Ni-CeO2 heterostructure-doped carbon nanofiber (Ni-CeO2 -CNF) is developed as an S host that combines the strong adsorption with the high catalytic activity and the good electrical conductivity, where the LiPSs anchored on the heterostructure surface can directly gain electrons from the current collector and realize a fast conversion between S8 and Li2 S. Therefore, Li-S batteries with S@Ni-CeO2 -CNF cathodes exhibit superior long-term cycling stability, with a capacity decay of 0.046% per cycle over 1000 cycles, even at 2 C. Noteworthy, under a sulfur loading up to 6 mg cm-2 , a high reversible areal capacity of 5.3 mAh cm-2 can be achieved after 50 cycles at 0.1 C. The heterostructure-modified S cathode effectively reconciles the thermodynamic and kinetic characteristics of LiPSs for adsorption and conversion, furthering the development of high-performance Li-S batteries.

18.
ACS Appl Mater Interfaces ; 13(47): 56109-56115, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34788007

RESUMO

Lithium metal has been perceived as an extremely attractive anode due to its superior energy density and low redox potential. However, great challenges affiliated with the operating security of Li metal batteries (LMBs) posed by growing Li dendrites hamper the widespread application of rechargeable LMBs. In this study, hierarchical hairball-like boron nitride (h-BN) was fabricated on a Li metal anode using the pulsed laser deposition (PLD) method. The chemically inert and mechanically robust dielectric h-BN coating on the Li anode can act as an interfacial layer conducive to enhancing the stability and extending the battery lifetime of LMBs by suppressing the formation and propagation of dendrites during the recurrent plating and stripping process. Moreover, the h-BN layer favors the drift of Li ions and mitigates electrolyte depletion, therefore demonstrating a reduced polarization in the voltage profiles, which further facilitates the uniform deposition of Li ions during battery operation. As proof, the Li/BN || BN/Li symmetrical cells can circulate steadily for 1800 h with no observable polarization at constant current density. Thus, the three-dimensional h-BN interface layer is efficacious for Li dendrite suppression during the practical application of LMBs, and it may also be promising for tackling dendrite issues in other metal ion battery systems.

19.
Plant Physiol Biochem ; 169: 343-359, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34837867

RESUMO

GATA transcription factors have been reported to function in plant growth and development and during various biotic/abiotic stresses in Arabidopsis and rice. However, the functions of wheat GATAs, particularly in the regulation of seed dormancy and germination, remain unclear. Here, we identified 78 TaGATAs in wheat and divided them into five subfamilies. Sixty-four paralogous pairs and 52 orthologous pairs were obtained, and Ka/Ks ratios showed that the TaGATAs had undergone strong purifying election during the evolutionary process. Triplet analysis indicated that a high homologue retention rate could explain the large number of TaGATAs in wheat. Gene structure analysis revealed that most members of the same subfamily had similar structures, and subcellular localization prediction indicated that most TaGATAs were located in the nucleus. Gene ontology annotation results showed that most TaGATAs had molecular functions in DNA and zinc binding, and promoter analysis suggested that they may play important roles in growth, development, and biotic/abiotic stress response. We combined three microarray datasets with qRT-PCR expression data from wheat varieties of contrasting dormancy and pre-harvest sprouting resistance levels during imbibition in order to identify ten candidate genes (TaGATA17/-25/-34/-37/-40/-46/-48/-51/-72/-73) that may be involved in the regulation of seed dormancy and germination in wheat. These findings provide valuable information for further dissection of TaGATA functions in the regulation of seed dormancy and germination, thereby enabling the improvement of wheat pre-harvest sprouting resistance by gene pyramiding.


Assuntos
Germinação , Oryza , Regulação da Expressão Gênica de Plantas , Germinação/genética , Dormência de Plantas/genética , Sementes/genética , Triticum/genética
20.
Angew Chem Int Ed Engl ; 60(47): 25122-25127, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34637181

RESUMO

K metal is the optimal anode for K-ion batteries because of its high capacity and low operating potential, but it suffers from fast capacity fading and safety issues due to an unstable solid electrolyte interphase (SEI) and continuous K-dendrite growth. Herein, to obtain promising potassium-metal batteries, a 3D polyvinyl-alcohol (PVA)-borax layer is designed, which enables a dendrite-free K-plating/stripping process. The protective layer possesses good wettability, high K-ion diffusivity, and good structural stability, which enables a "uniform and underneath plating" behavior, therefore exhibiting a stable electrochemical performance. As a result, Cu current collector with PVA-borax (PVA-borax@Cu) exhibits a stable cycling lifetime for 700 h at 0.5 mA cm-2 and 500 h at 1 mA cm-2 at 10 % depth of discharge (DOD) without dendrite formation. Even at a high utilization of 25 % DOD and 50 % DOD, the PVA-borax@Cu shows a stable cycle for 180 h and 100 h, respectively.

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