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1.
Molecules ; 29(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731571

RESUMEN

The dyes in printing and dyeing wastewater are harmful to the human body and the environment. It is essential to develop practical and effective adsorbents to deal with them. In this study, an Fe-doped, ZIF-67 derived Fe/Co/C composite material with strong magnetism was successfully synthesized. The effects of pH, initial concentration, and adsorption time on the properties of the adsorbent were investigated. To further improve the removal efficiency and enhance the practicality, potassium peroxymonosulfate (PMS) was added to the system due to its Fenton-like effect. Then, an Fe/Co/C composite was used with PMS to remove Congo red (CR) with a 98% removal of 250 mg·L-1. Moreover, for its high saturation magnetization of 85.4 emu·g-1, the Fe/Co/C composite can be easily recovered by applying a magnetic field, solving the problem that powdery functional materials are difficult to recover and, thus, avoiding secondary pollution. Furthermore, since the composite material was doped before carbonization, this synthetic strategy is flexible and the required metal elements can be added at will to achieve different purposes. This study demonstrates that this Fe-doped, ZIF-67 derived magnetic material has potential application prospects for dye adsorption.

2.
J Colloid Interface Sci ; 670: 428-438, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38772259

RESUMEN

Although photocatalytic H2 production based on semiconductor materials has a wide potential application, it still facing challenges such as slow reaction kinetics or complex synthesis processes. To meet these challenges, the carbon dots loaded black g-C3N4 (CN-B-CDs) was synthesized by simple calcination method to achieve efficient photothermal-assisted photocatalytic H2 production. Photothermal imaging experiments confirmed the photothermal effect of CN-B and CDs as dual heat sources to increase the temperature of the composite system, thus improving the effective separation of photo-generated charges. In addition, multiple photocatalytic H2 production tests exhibited that CN-B-CDs photocatalysts not only have strong stability but also can accommodate a variety of complex water bodies, which displayed the potential for industrial application. This study combined the photothermal effect and the mechanism by which the CDs promote the charge transfer to design a new photocatalytic H2 production system and provided a new scheme for achieving efficient photothermal-assisted photocatalytic H2 production using carbon-based materials.

3.
J Colloid Interface Sci ; 669: 126-136, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38713952

RESUMEN

The shuttle effect and sluggish redox kinetics of polysulfides have hindered the development of lithium-sulfur batteries (LSBs) as premier energy storage devices. To address these issues, a high-entropy metal phosphide (NiCoMnFeCrP) was synthesized using the sol-gel method. NiCoMnFeCrP, with its rich metal species, exhibits strong synergistic effects and provides numerous catalytic active sites for the conversion of polysulfides. These active sites, possessing significant polarity, can bond with polysulfides. In situ ultraviolet-visible were conducted to monitor the dynamic changes in species and concentrations of polysulfides, validating the ability of NiCoMnFeCrP to facilitate the conversion of polysulfides. The batteries with the NiCoMnFeCrP catalyst as functional separators exhibited minimal capacity decay rates of 0.04 % and 0.23 % after 100 cycles at 0 °C and 60 °C, respectively. This indicates that the NiCoMnFeCrP catalyst possesses good thermal stability. Meanwhile, its area capacity can reach 4.78 mAh cm-2 at a high sulfur load of 4.54 mg cm-2. In conclusion, NiCoMnFeCrP achieves the objective of mitigating the shuttle effect and accelerating the kinetics of the redox reaction, thereby facilitating the commercialization of LSBs.

4.
Ecol Evol ; 14(5): e11437, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38756686

RESUMEN

In predator-prey interactions, the prey faces extreme challenges from predation, which drives the evolution of defense or anti-predator mechanisms. Compared with adult birds, nestlings are more vulnerable but not helpless. However, data on whether nestlings eavesdrop on the danger signals transmitted by other prey nestlings and the mechanisms of eavesdropping remain limited. In brood parasitism, common cuckoo (Cuculus canorus) nestlings, raised by host adults who are not closely related, offer an instructive system for studying the transmission and recognition of danger signals among nestlings of different species that share special relationships. We played back the distress calls of common cuckoo nestlings to nestlings of three sympatric host species (the oriental reed warbler Acrocephalus orientalis, which is a primary host of the common cuckoo, the reed parrotbill Paradoxornis heudei, an occasional host, and the vinous-throated parrotbill Sinosuthora webbiana, which is not parasitized in the study area) to investigate whether the host nestlings reduced their begging behavior. We also quantified the degree of inhibition toward begging behavior for these nestlings. The results revealed that, in response to the distress calls, the three sympatric host species markedly suppressed their begging behavior. This response can likely be attributed to the innate response of host nestlings caused by the general characteristics of distress calls, rather than the acoustic similarity and phylogenetic relationship between host nestlings and cuckoo nestlings. Furthermore, we observed that upon hearing the distress calls of cuckoo nestlings, the oriental reed warbler nestlings exhibited the greatest reduction in the total number of calls compared to the other two host species, potentially owing to stronger predation and parasitic pressures. This study suggests that host nestlings can detect danger signals emitted by parasitic nestlings; however, further investigation is needed to determine whether they can respond to distress calls from unfamiliar nestlings in different regions.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38605680

RESUMEN

OBJECTIVES: Based on the "linked lives" tenant of the life course perspective, this longitudinal study aims to examine the actor and partner effects of social participation on cognitive function in older Chinese couples. METHODS: A total of 1,706 couples aged 60 and older were included in the final analyses. Social participation was measured using 2 questions regarding types of activities and frequency. Cognitive function was measured using a combination of memory, orientation, visuoconstruction, attention, and calculation. The lagged-dependent APIM was used to model the dyadic associations between social participation and cognitive function. RESULTS: The time-averaged actor effects of both husbands' and wives' social participation on their own cognitive function were significant (p < .001 for both). The time-averaged partner effect of husbands' social participation on wives' cognitive function was significant (p < .001) but the reverse-the effect of wives' social participation on husbands' cognitive function-was not (p = .381). The time-specific actor and partner effects were not significant (p > .05 for all). DISCUSSION: Our findings indicate an asymmetrical pattern of actor-partner interdependence, where husbands' social participation may affect their wives' cognitive function on average, but wives' social participation does not affect their husbands' cognitive function. Clinical practitioners should invite both partners, especially husbands, to participate in social participation interventions to facilitate crossover benefits for wives. Moreover, policymakers should build more facilities to encourage older couples to engage in social activities to prevent cognitive decline.


Asunto(s)
Cognición , Participación Social , Esposos , Humanos , Masculino , Participación Social/psicología , Femenino , Anciano , Estudios Longitudinales , China , Esposos/psicología , Persona de Mediana Edad , Anciano de 80 o más Años , Envejecimiento/psicología , Relaciones Interpersonales , Pueblos del Este de Asia
6.
BMC Plant Biol ; 24(1): 224, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38539093

RESUMEN

BACKGROUND: Drought severely limits sunflower production especially at the seedling stage. To investigate the response mechanism of sunflowers to drought stress, we utilized two genotypes of sunflower materials with different drought resistances as test materials. The physiological responses were investigated under well-watered (0 h) and drought-stressed conditions (24 h, 48 h, and 72 h). RESULTS: ANOVA revealed the greatest differences in physiological indices between 72 h of drought stress and 0 h of drought stress. Transcriptome analysis was performed after 72 h of drought stress. At 0 h, there were 7482 and 5627 differentially expressed genes (DEGs) in the leaves of K55 and K58, respectively, and 2150 and 2527 DEGs in the roots of K55 and K58, respectively. A total of 870 transcription factors (TFs) were identified among theDEGs, among which the high-abundance TF families included AP2/ERF, MYB, bHLH,and WRKY. Five modules were screened using weighted gene coexpressionnetwork analysis (WGCNA), three and two of which were positively and negatively, respectively, related to physiological traits. KEGG analysis revealedthat under drought stress, "photosynthesis", "carotenoid biosynthesis", "starch and sucrose metabolism", "ribosome", "carotenoid biosynthesis", "starch and sucrose metabolism", "protein phosphorylation" and "phytohormone signaling" are six important metabolic pathways involved in the response of sunflower to drought stress. Cytoscape software was used to visualize the three key modules, and the hub genes were screened. Finally, a total of 99 important candidate genes that may be associated with the drought response in sunflower plants were obtained, and the homology of these genes was compared with that in Arabidopsis thaliana. CONCLUSIONS: Taken together, our findings could lead to a better understanding of drought tolerance in sunflowers and facilitate the selection of drought-tolerant sunflower varieties.


Asunto(s)
Arabidopsis , Helianthus , Humanos , Transcriptoma , Helianthus/genética , Helianthus/metabolismo , Resistencia a la Sequía , Perfilación de la Expresión Génica , Sequías , Arabidopsis/genética , Almidón/metabolismo , Carotenoides/metabolismo , Sacarosa/metabolismo , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas
7.
Inorg Chem ; 63(11): 5076-5082, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38447153

RESUMEN

Herein, two Laves intermetallic series, ZrCo1.75M0.25 and NbCo1.75M0.25 (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt), were synthesized, and their hydrogen evolution reaction (HER) activities were examined to reveal the influence of d electrons to the corresponding HER activities. Owing to the different electronegativity between Zr and Nb (χZr = 1.33; χNb = 1.60), Co and/or M elements receive more electrons in ZrCo1.75M0.25 than that of the Nb one. This leads to the overall weak H adsorption energy (ΔGHad) of ZrCo1.75M0.25 series compared to that of NbCo1.75M0.25 and rationalizes well the superior HER activity of the Rh member compared to that of the Pt one in the ZrCo1.75M0.25 series. Under industrial conditions (333 K, 6.0 M KOH), ZrCo1.75Rh0.25 only requires an overpotential of 110 mV to reach the current density of 500 mA/cm2 and can be operated at high current density over 400 h. This work demonstrates that with a proper combination between elements in intermetallic phases, one can manipulate d electrons of the active metal to be closer to the sweet spot (ΔGHad = 0). The Pt member may no longer exhibit the best HER activity in series, and all elements exhibit the potential to outperform the Pt member in the HER with careful control of the d electron population.

8.
Ecol Evol ; 14(2): e11063, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38380067

RESUMEN

Egg recognition and rejection are the most common and effective anti-parasitic strategies against avian brood parasitism in terms of maintaining stability over time and plasticity in response to environmental cues. Conversely, parasites have evolved multiple counter-adaptations to the anti-parasitic defenses of hosts. Among them, the crypsis hypothesis suggests that eggs that appear more cryptic in color and are closely matched to the environment are helping to counter the egg recognition strategy of the host. In this study, we investigated whether the egg recognition ability of Oriental reed warblers (Acrocephalus orientalis), a common host of common cuckoos (Cuculus canorus), changed during different reproductive stages by using model egg experiments. The effect of the crypsis hypothesis on the egg recognition ability of the hosts was also investigated by controlling the color contrast between the inside of the experimental nests and the model eggs. The results showed that the Oriental reed warbler retained strong egg recognition abilities, which were similar to the incubation stage (GLMMs: F 1,27 = 0.424, p = .521), even after entering the nestling stage and preferentially rejected model eggs with distinct contrasting colors (binomial test: Fisher's exact, p = .016). These results are consistent with the crypsis hypothesis. The present study suggests that the host retains a strong egg recognition ability even during the nestling stage and that cryptic-colored eggs that are closely matched with the breeding nest environment help counter the host's egg recognition abilities and increase the chances of successful parasitism by cuckoos. However, the effectiveness of cryptic egg may be weaker than mimic egg in countering egg recognition and rejection by hosts with open-cup nests.

9.
Adv Mater ; 36(18): e2312868, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38241728

RESUMEN

The intelligent construction of non-noble metal materials that exhibit reversible oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with bifunctional electrocatalytic performance is greatly coveted in the realm of zinc-air batteries (ZABs). Herein, a crafted structure-amorphous MnO2 lamellae encapsulated covalent triazine polymer-derived N, S, P co-doped carbon sphere (A-MnO2/NSPC) is designed using a self-doped pyrolysis coupled with an in situ encapsulation strategy. The customized A-MnO2/NSPC-2 demonstrates a superior bifunctional electrocatalytic performance, confirmed by a small ΔE index of 0.64 V for ORR/OER. Experimental investigations, along with density functional theory calculations validate that predesigned amorphous MnO2 surface defects and abundant heteroatom catalytic active sites collectively enhance the oxygen electrocatalytic performance. Impressively, the A-MnO2/NSPC-based rechargeable liquid ZABs show a large open-circuit potential of 1.54 V, an ultrahigh peak power density of 181 mW cm-2, an enormous capacity of 816 mAh g-1, and a remarkable stability for more than 1720 discharging/charging cycles. Additionally, the assembled flexible all-solid-state ZABs also demonstrate outstanding cycle stability, surpassing 140 discharging/charging cycles. Therefore, this highly operable synthetic strategy offers substantial understanding in the development of magnificent bifunctional electrocatalysts for various sustainable energy conversions and beyond.

10.
Adv Sci (Weinh) ; : e2400364, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38251278

RESUMEN

Sodium-ion batteries (SIBs) and sodium-ion capacitors (SICs) are promising candidates for cost-effective and large-scale energy storage devices. However, sluggish kinetics and low capacity of traditional anode materials inhibit their practical applications. Herein, a novel design featuring a layer-expanded MoS2 is presented that dual-reinforced by hollow N, P-codoped carbon as the inner supporter and surface groups abundant MXene as the outer supporter, resulting in a cross-linked robust composite (NPC@MoS2 /MXene). The hollow N, P-codoped carbon effectively prevents agglomeration of MoS2 layers and facilitates shorter distances between the electrolyte and electrode. The conductive MXene outer surface envelops the NPC@MoS2 units inside, creating interconnected channels that enable efficient charge transfer and diffusion, ensuring rapid kinetics and enhanced electrode utilization. It exhibits a high reversible capacity of 453 mAh g-1 , remarkable cycling stability, and exceptional rate capability with 54% capacity retention when the current density increases from 100 to 5000 mA g-1 toward SIBs. The kinetic mechanism studies reveal that the NPC@MoS2 /MXene demonstrates a pseudocapacitance dominated hybrid sodiation/desodiation process. Coupled with active carbon (AC), the NPC@MoS2 /MXene//AC SICs achieve both high energy density of 136 Wh kg-1 at 254 W kg-1 and high-power density of 5940 W kg-1 at 27 Wh g-1 , maintaining excellent stability.

11.
J Environ Sci (China) ; 138: 418-427, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38135407

RESUMEN

Bi2O2CO3(BOC)/Bi4O5Br2(BOB)/reduced graphene oxide (rGO) Z-scheme heterojunction with promising photocatalytic properties was synthesized via a facile one-pot room-temperature method. Ultra-thin nanosheets of BOC and BOB were grown in situ on rGO. The formed 2D/2D direct Z-scheme heterojunction of BOC/BOB with oxygen vacancies (OVs) effectively leads to lower negative electron reduction potential of BOB as well as higher positive hole oxidation potential of BOC, showing improved reduction/oxidation ability. Particularly, rGO is an acceptor of the electrons from the conduction band of BOC. Its dual roles significantly improve the transfer performance of photo-induced charge carriers and accelerate their separation. With layered nanosheet structure, rich OVs, high specific surface area, and increased utilization efficiency of visible light, the multiple synergistic effects of BOC/BOB/rGO can achieve effective generation and separation of the electron-holes, thereby generating more •O2- and h+. The photocatalytic reduction efficiency of CO2 to CO (12.91 µmol/(g·hr)) is three times higher than that of BOC (4.18 µmol/(g·hr)). Moreover, it also achieved almost 100% removal of Rhodamine B and cyanobacterial cells within 2 hours.


Asunto(s)
Electrones , Grafito , Temperatura , Oxígeno
12.
ACS Appl Mater Interfaces ; 16(1): 633-642, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38150331

RESUMEN

It is highly desirable to fabricate transition bimetallic alloy-embedded porous nanocarbons with a unique nanoarchitecture for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in rechargeable zinc-air batteries. In this work, we introduce a template-assisted in situ alloying synthesis of FeNi alloy nanoparticle-decorated coral-like nanocarbons (FeNi-CNCs) as efficient OER/ORR dual-functional electrocatalysts. The present materials are produced through polycondensation of a covalent triazine framework (CTF), the coordination of Ni and Fe ions, and sequential pyrolytic treatment. Through the pyrolysis process, the nanolamellar FeNi-CTF precursors can be facilely converted into FeNi alloy nanoparticle-decorated nanocarbons. These nanocarbons possess a distinctive three-dimensional (3D) coral-like nanostructure, which is favorable for the transport of oxygen and the diffusion of electrolyte. As a result, FeNi-CNC-800 with the highest efficiency exhibited remarkable electrocatalytic performance and great durability. Additionally, it also can be assembled into rechargeable zinc-air batteries that can be assembled in both liquid and solid forms, offering a superior peak power density, large specific capacity, and outstanding reusability during charging/discharging cycles (e.g., 5160 charging-and-discharging cycles at 10 mA cm-2 for the liquid forms). These traits make it a highly promising option in the burgeoning field of wearable energy conversion.

13.
J Psychosom Res ; 176: 111563, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38103280

RESUMEN

OBJECTIVE: Illness perceptions direct coping resources in the illness adaptation process. Previous studies regarding illness perception profiles have been conducted at the individual level, without considering the couple as a unit. This study aimed to investigate the dyadic topologies of illness perceptions in HIV-serodiscordant couples and the association between the identified profiles and individual- and couple-level outcomes. METHODS: A comprehensive examination was undertaken, encompassing 231 Chinese HIV-serodiscordant couples, who voluntarily participated in this cross-sectional study during the period spanning June to October 2022. To discern various patterns of illness perception, dyadic latent profile analyses were performed, followed by the implementation of one-way analyses of variance to investigate outcome differences at both the individual and couple levels across the identified profiles. RESULTS: We identified three distinct profiles of illness perception, namely the incongruent-but-low, congruent-but-high, and incongruent-and-high profiles. Except for the partner's sex (p < .01, Cramer' v = 0.214) and the education levels of persons living with HIV and their partners (both p < .01, Cramer' v = 0.236 for persons living with HIV and 0.198 for partners), no significant demographic differences across the various profiles were found. Furthermore, we observed significant differences in all outcomes among the different couple profiles (all p < .001). These differences were of medium-to-large magnitudes (partial η2 values ranging from 0.07 to 0.22). CONCLUSION: A couple-centered typological approach provides a useful way of identifying the couple's configuration of illness perceptions, which will inform the provision of tailor-made treatment for couples with different profiles.


Asunto(s)
Infecciones por VIH , Parejas Sexuales , Humanos , Estudios Transversales , VIH , Pueblos del Este de Asia
14.
Phys Chem Chem Phys ; 25(42): 29182-29191, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37870596

RESUMEN

In recent years, two-dimensional materials have aroused enormous interest owing to their superior electrochemical performance, abundant exposed active sites, high specific surfaces and so on. Unlike many stable allotropes, honeycomb hexagonal borophene is kinetically unstable. In this study, we introduce transition metal atoms (Cr, Fe and Co) to stabilize honeycomb hexagonal borophene, forming stable graphene-like TMB6 (TM = Cr, Fe and Co) monolayers. Moreover, we explored the possibility of superconductivity and the anchoring materials of lithium-sulfur batteries using the first-principles density functional theory (DFT) calculation. Our results show that CoB6 exhibited the best superconductivity with a superconducting transition temperature of 33.3 K. Furthermore, CoB6 and FeB6 are promising anchoring materials because of the suppression of lithium polysulfides shuttling in lithium-sulfur batteries because they can accelerate sulfur reduction reaction kinetics.

15.
J Mol Model ; 29(10): 314, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37707644

RESUMEN

CONTEXT: The adsorptions of toxic gases SO2 and H2S on 2D α/ß/γ-FeB6 monolayer were investigated using density functional theory calculations. To analyze the interaction between gas molecule H2S/SO2 and α/ß/γ-FeB6 monolayer, we calculated adsorption energy, adsorption distance, Mullikan charge, charge density difference, band structure, the density of states, work function, and theoretical recovery time. The adsorption energies show that H2S/SO2 is chemisorbed on α/ß-FeB6 while H2S/SO2 is physiosorbed on γ-FeB6 monolayer. As a result, γ-FeB6 has a short recovery time for H2S (5.71×10-8 s)/SO2 (1.94×10-5 s) due to modest adsorption. Therefore, γ-FeB6 may be a promising candidate for reusable H2S/SO2 sensors at room temperature. Although H2S is chemisorbed on α/ß-FeB6, as the working temperature rises to 500 K, the recovery time of α/ß-FeB6 for H2S can decrease to 1.13×10-1 s and 2.08×10-1 s, respectively, which are well within the detectable range. So, α/ß-FeB6 monolayer also may be a good candidate for H2S gas sensor. METHODS: Calculations were performed at GGA-PBE/DNP level using the Dmol3 module implemented in the Material Studio 2018 software package.

16.
Ann Behav Med ; 57(11): 978-987, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37435876

RESUMEN

BACKGROUND: Since HIV has evolved into a lifelong but manageable condition, improving the quality of life (QoL) of persons living with HIV (PLWHs) has become increasingly important. Living with HIV is life-altering and poses substantial challenges for both PLWHs and their partners, so identifying how HIV serodiscordant couples cope with HIV together is crucial. Here, Bodenmann's Systemic Transaction Model highlights common dyadic coping (CDC), which refers to both partners working together to alleviate the negative effects of stress. PURPOSE: We examined the mediating role of CDC in linking we-disease appraisal with relationship satisfaction and QoL. METHODS: We recruited a convenience sample of 231 HIV serodiscordant couples via local grassroots organizations between June and October 2022. Participants completed measures of we-disease appraisal, CDC, relationship satisfaction, and QoL. We examined the mediation effect of CDC on the association between we-disease appraisal and outcomes using the common fate mediation model. RESULTS: The mean age of PLWHs was 32.18 years (standard deviation = 8.61 years), and that of their partners was 32.55 years (standard deviation = 9.24 years). The average time since HIV diagnosis was 4.18 years. Most couples were same-sex male couples. We found that CDC mediated the effect of we-disease appraisal on relationship satisfaction. Moreover, CDC significantly mediated the effect of we-disease appraisal on the QoL of PLWHs and their partners. CONCLUSIONS: Our findings highlight the importance of CDC in dyadic illness management among Chinese HIV serodiscordant couples.


Numerous studies have shown that HIV serodiscordant couples may face HIV-related stress as a unit. Yet, it is not clear how the appraisal of HIV as a shared illness (i.e., we-disease appraisal) may influence relationship satisfaction and both partners' quality of life (QoL) via common dyadic coping (CDC) behaviors (e.g., collaboration). In this study, we collected data from 231 HIV serodiscordant couples. Participants completed reports of how they appraise HIV as a we-disease, their CDC behaviors, and their relationship satisfaction and QoL. We found that we-disease appraisal was positively associated with CDC, which in turn was positively associated with relationship satisfaction and both partners' QoL. Future couple-based interventions should incorporate psycho-educational components to raise awareness about we-disease appraisal, as well as skill-building components to encourage the use of CDC in clinical settings.

17.
ACS Nano ; 17(13): 12278-12289, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37377176

RESUMEN

A catalyst kinetics optimization strategy based on tuning active site intermediates adsorption is proposed. Construction of the M-OOH on the catalytic site before the rate-determining step (RDS) is considered a central issue in the strategy, which can optimize the overall catalytic kinetics by avoiding competition from other reaction intermediates on the active site. Herein, the kinetic energy barrier of the O-O coupling for as-prepared sulfated Co-NiFe-LDH nanosheets is significantly reduced, resulting in the formation of M-OOH on the active site at low overpotential, which is directly confirmed by in situ Raman and charge transfer fitting results. Moreover, catalysts constructed from active sites of highly efficient intermediates make a reliable model for studying the mechanism of the OER in proton transfer restriction. In weakly alkaline environments, a sequential proton-electron transfer (SPET) mechanism replaces the concerted proton-electron transfer (CPET) mechanism, and the proton transfer step becomes the RDS; high-speed consumption of reaction intermediates (M-OOH) induces sulfated Co-NiFe-LDH to exhibit excellent kinetics.

18.
PeerJ ; 11: e15275, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37159834

RESUMEN

Sunflower is an important oilseed crop across the world. It is considered as a moderately drought tolerant plant, however, its yield is still negatively affected by drought stress. Improving drought tolerance is of the outmost important for breeding. Although several studies have documented the relationship between the sunflower phenotype and genotype under drought stress, but relatively few studies have simultaneously investigated the molecular mechanisms of drought tolerance in the sunflower at different growth stages. In this study, we conducted quantitative trait locus (QTL) analysis for different sunflower traits during the germination and seedling stages. Eighteen phenotypic traits were evaluated under well-watered and drought stress conditions. We determined that the germination rate, germination potential, germination index, and root-to-shoot ratio can be used as effective indexes for drought tolerance selection and breeding. A total of 33 QTLs were identified on eight chromosomes (PVE: 0.016%-10.712% with LOD: 2.017-7.439). Within the confidence interval of the QTL, we identified 60 putative drought-related genes. Four genes located on chromosome 13 may function in both germination and seedling stages for drought response. Genes LOC110898128, LOC110898092, LOC110898071, and LOC110898072 were annotated as aquaporin SIP1-2-like, cytochrome P450 94C1, GABA transporter 1-like, and GABA transporter 1-like isoform X2, respectively. These genes will be used for further functional validation. This study provides insight into the molecular mechanisms of the sunflower's in response to drought stress. At the same time, it lays a foundation for sunflower drought tolerance breeding and genetic improvement.


Asunto(s)
Asteraceae , Helianthus , Helianthus/genética , Plantones/genética , Germinación/genética , Sequías , Proteínas Transportadoras de GABA en la Membrana Plasmática , Fitomejoramiento , Acuaporina 2
19.
Small Methods ; 7(9): e2300050, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37144659

RESUMEN

An electrical-biased or mechanical-loaded scanning probe written on the ferroelectric surface can generate programmable domain nanopatterns for ultra-scaled and reconfigurable nanoscale electronics. Fabricating ferroelectric domain patterns by direct-writing as quickly as possible is highly desirable for high response rate devices. Using monolayer α-In2 Se3 ferroelectric with ≈1.2 nm thickness and intrinsic out-of-plane polarization as an example, a writing-speed dependent effect on ferroelectric domain switching is discovered. The results indicate that the threshold voltages and threshold forces for domain switching can be increased from -4.2 to -5 V and from 365 to 1216 nN, respectively, as the writing-speed increases from 2.2 to 10.6 µm s-1 . The writing-speed dependent threshold voltages can be attributed to the nucleations of reoriented ferroelectric domains, in which sufficient time is needed for subsequent domain growth. The writing-speed dependent threshold forces can be attributed to the flexoelectric effect. Furthermore, the electrical-mechanical coupling can be employed to decrease the threshold force, achieving as low as ≈189±41 nN, a value smaller than those of perovskite ferroelectric films. Such findings reveal a critical issue of ferroelectric domain pattern engineering that should be carefully addressed for programmable direct-writing electronics applications.

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