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1.
Sci Total Environ ; 927: 172292, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588741

RESUMO

Trace element pollution has emerged as an increasingly severe environmental challenge owing to human activities, particularly in urban ecosystems. In farmlands, invasive species commonly outcompete native species when subjected to trace element treatments, as demonstrated in experiments with individual invader-native pairs. However, it is uncertain if these findings apply to a wider range of species in urban soils with trace elements. Thus, we designed a greenhouse experiment to simulate the current copper and zinc levels in urban soils (102.29 mg kg-1 and 148.32 mg kg-1, respectively). The experiment involved four pairs of invasive alien species and their natural co-existing native species to investigate the effects of essential trace elements in urban soil on the growth and functional traits of invasive and native species, as well as their interspecific relationship. The results showed that adding trace elements weakened the competitiveness of invasive species. Nonetheless, trace element additions did not change the outcome of competition, consistently favoring invasion successfully. Under trace element addition treatments, invasive species and native species still maintained functional differentiation trend. Furthermore, the crown area, average leaf area and leaf area per plant of invasive species were higher than those of native species by 157 %, 177 % and 178 % under copper treatment, and 194 %, 169 % and 188 % under zinc treatment, respectively. Additionally, interspecific competition enhanced the root growth of invasive species by 21 % with copper treatment and 14 % with zinc treatment. The ability of invasive species to obtain light energy and absorb water and nutrients might be the key to their successful invasion.


Assuntos
Espécies Introduzidas , Poluentes do Solo , Oligoelementos , Oligoelementos/análise , Poluentes do Solo/análise , Solo/química , Ecossistema , Plantas/efeitos dos fármacos , Cobre , Zinco
3.
Sci Signal ; 17(829): eadk8249, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530880

RESUMO

Mutations in the gene encoding the lysosomal enzyme glucocerebrosidase (GCase) are responsible for Gaucher disease (GD) and are considered the strongest genetic risk factor for Parkinson's disease (PD) and Lewy body dementia (LBD). GCase deficiency leads to extensive accumulation of glucosylceramides (GCs) in cells and contributes to the neuropathology of GD, PD, and LBD by triggering chronic neuroinflammation. Here, we investigated the mechanisms by which GC accumulation induces neuroinflammation. We found that GC accumulation within microglia induced by pharmacological inhibition of GCase triggered STING-dependent inflammation, which contributed to neuronal loss both in vitro and in vivo. GC accumulation in microglia induced mitochondrial DNA (mtDNA) leakage to the cytosol to trigger STING-dependent inflammation. Rapamycin, a compound that promotes lysosomal activity, improved mitochondrial function, thereby decreasing STING signaling. Furthermore, lysosomal damage caused by GC accumulation led to defects in the degradation of activated STING, further exacerbating inflammation mediated by microglia. Thus, limiting STING activity may be a strategy to suppress neuroinflammation caused by GCase deficiency.


Assuntos
Doença de Gaucher , Doença de Parkinson , Animais , Camundongos , alfa-Sinucleína/metabolismo , Doença de Gaucher/genética , Doença de Gaucher/patologia , Glucosilceramidas/metabolismo , Inflamação/metabolismo , Lisossomos/metabolismo , Microglia/metabolismo , Doenças Neuroinflamatórias , Doença de Parkinson/metabolismo
4.
Microorganisms ; 12(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38543528

RESUMO

Endophytes play an important role in helping plants resist heavy metal stress. However, little is known about the effects of different heavy metals on the diversity and composition of endophyte communities. In this study, we used 16S and ITS amplicon sequencing to reveal the structure and function of endophytes in Symphytum officinale under different heavy metal stressors. The results showed that the endophytic fungal diversity decreased compared with the control under the different heavy metals stressors, while the diversity of endophytic bacteria showed an increasing trend. The biomarker analysis indicated that Zn and Pb stress led to obvious branches. Specific OTUs analysis showed that there were 1224, 597, and 1004 OTUs specific under Zn, Pb, and Cd stress in the bacterial community and 135, 81, and 110 OTUs specific under Zn, Pb, and Cd stress in the fungal community. The co-occurrence network showed changes in microbial interactions under heavy metal contamination conditions, suggesting that endophytic bacteria play an important role in the resistance of host plants. The Spearman analysis showed that the correlation between endophytic bacteria and endophytic fungi in relation to heavy metal transport exhibited variations. Our results expand the knowledge of the relationships of plant-microbe interactions and offer pivotal information to reveal the role of endophytes under different heavy metal stress conditions.

5.
J Colloid Interface Sci ; 661: 740-749, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38325172

RESUMO

Perovskite nanocrystals (PNCs) have attracted extensive attention for their potential applications in biology. However, only a handful of PNCs have been scrutinized in the biological domain due to issues such as instability, poor dispersion, and size inhomogeneity in polar solvents. The development of dual-functional perovskite nanomaterials with hydrogen sulfide (H2S) sensing and antibacterial capabilities is particularly intriguing. In this study, we prepared chiral quasi-two-dimensional (quasi-2D) perovskite nanomaterials, Bio(S-PEA)2CsPb2Br7 and Bio(R-PEA)2CsPb2Br7, that were uniformly dispersed in aqueous media. The effective encapsulation of methoxypolyethylene glycol amine (mPEG-NH2) improved water stability and uniformity of particle size. Circular dichroism (CD) signals were created by the successful insertion of chiral cations. These perovskites as probes showed a rapid and sensitive fluorescence quenching response to H2S, and the effect of imaging detection was observed at the Escherichia coli (E. coli) level. As antibacterial agents, their pronounced positive charge properties facilitated membrane lysis and subsequent E. coli death, indicating a significant antibacterial effect. This work has preliminary explored the application of chiral perovskites in biology and provides insight into the development of bifunctional perovskite nanomaterials for biological applications.


Assuntos
Compostos de Cálcio , Sulfeto de Hidrogênio , Óxidos , Polietilenoglicóis , Titânio , Sulfeto de Hidrogênio/farmacologia , Escherichia coli , Água , Antibacterianos/farmacologia
6.
Int J Biol Sci ; 20(3): 987-1003, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250160

RESUMO

Fibroblast activation and proliferation is an essential phase in the progression of renal fibrosis. Despite the recognized significance of glutamine metabolism in cellular growth and proliferation, its precise pathophysiological relevance in renal fibrosis remains uncertain. Therefore, this study aims to investigate the involvement of glutamine metabolism in fibroblast activation and its possible mechanism. Our findings highlight the importance of glutamine metabolism in fibroblast activation and reveal that patients with severe fibrosis exhibit elevated serum glutamine levels and increased expression of kidney glutamine synthetase. Furthermore, the deprivation of glutamine metabolism in vitro and in vivo could inhibit fibroblast activation, thereby ameliorating renal fibrosis. It was also detected that glutamine metabolism is crucial for maintaining mitochondrial function and morphology. These effects may partially depend on the metabolic intermediate α-ketoglutaric acid. Moreover, glutamine deprivation led to upregulated mitochondrial fission in fibroblasts and the activation of the mammalian target of rapamycin / mitochondrial fission process 1 / dynamin-related protein 1 pathway. Thus, these results provide compelling evidence that the modulation of glutamine metabolism initiates the regulation of mitochondrial function, thereby facilitating the progression of renal fibrosis. Consequently, targeting glutamine metabolism emerges as a novel and promising avenue for therapeutic intervention and prevention of renal fibrosis.


Assuntos
Glutamina , Nefropatias , Humanos , Dinâmica Mitocondrial , Mitocôndrias , Fibrose
7.
J Exp Clin Cancer Res ; 43(1): 35, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287371

RESUMO

BACKGROUND: Hepatocellular Carcinoma (HCC) is a matter of great global public health importance; however, its current therapeutic effectiveness is deemed inadequate, and the range of therapeutic targets is limited. The aim of this study was to identify early growth response 1 (EGR1) as a transcription factor target in HCC and to explore its role and assess the potential of gene therapy utilizing EGR1 for the management of HCC. METHODS: In this study, both in vitro and in vivo assays were employed to examine the impact of EGR1 on the growth of HCC. The mouse HCC model and human organoid assay were utilized to assess the potential of EGR1 as a gene therapy for HCC. Additionally, the molecular mechanism underlying the regulation of gene expression and the suppression of HCC growth by EGR1 was investigated. RESULTS: The results of our investigation revealed a notable decrease in the expression of EGR1 in HCC. The decrease in EGR1 expression promoted the multiplication of HCC cells and the growth of xenografted tumors. On the other hand, the excessive expression of EGR1 hindered the proliferation of HCC cells and repressed the development of xenografted tumors. Furthermore, the efficacy of EGR1 gene therapy was validated using in vivo mouse HCC models and in vitro human hepatoma organoid models, thereby providing additional substantiation for the anti-cancer role of EGR1 in HCC. The mechanistic analysis demonstrated that EGR1 interacted with the promoter region of phosphofructokinase-1, liver type (PFKL), leading to the repression of PFKL gene expression and consequent inhibition of PFKL-mediated aerobic glycolysis. Moreover, the sensitivity of HCC cells and xenografted tumors to sorafenib was found to be increased by EGR1. CONCLUSION: Our findings suggest that EGR1 possesses therapeutic potential as a tumor suppressor gene in HCC, and that EGR1 gene therapy may offer benefits for HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Regulação Neoplásica da Expressão Gênica , Glicólise , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/metabolismo , Sorafenibe/farmacologia
8.
Chemosphere ; 349: 140789, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38013025

RESUMO

Two sulfate-reducing wetland bioreactors (SRB-1 filled with lignocellulosic wastes and SRB-2 with river sand) were applied for synthetic acid mine drainage treatment with bio-waste fermentation liquid as electron donor, and the influence of filling substrates on sulfate reduction, sulfur transformation and microbial community was studied. The presence of lignocellulosic wastes (mixture of cow manure, bark, sawdust, peanut shell and straw) in SRB-1 promoted sulfate reduction efficiency (68.9%), sulfate reduction rate (42.1 ± 11 mg S/(L·d)), dissolved sulfide production rate (27.4 ± 7 mg S/(L·d)), and particularly caused high conversion ratio of sulfate reduction into dissolved sulfide (66.4%). In comparison, the relatively low sulfate reduction efficiency (42.9%), sulfate reduction rate (27.0 ± 10 mg S/(L·d)), dissolved sulfide production rate (5.6 ± 3 mg S/(L·d)) and low dissolved sulfide conversion efficiency (21.2%) occurred in SRB-2. Mixed organic substrates including easily assimilated electron donors (in manure) and lignocellulosic matter were effective to promote quick start and long-term microbial sulfate reduction. More than 98% of produced dissolved sulfide was oxidized dominantly by photoautotrophic green sulfur bacteria (genera Chlorobium and Chlorobaculum), of which 64.6% and 54.5% was converted into elemental sulfur for SRB-1 and SRB-2. The oxidation of sulfide into elemental sulfur for potential recovery rather than sulfate is preferred. Diverse sulfate reducing bacteria and sulfide oxidizing bacteria co-existed in the treatment system, which led to a sustainable sulfur transformation. High metal removal efficiency for Fe (99.6%, 92.5%), Cd (99.9%, 99.9%), Zn (99.4%, 98.5%), Cu (94.5%, 94.6%) except for Mn (9.3%, 3.6%) was achieved, and effluent pH increased to 6.5-7.7 and 6.7-7.7 for SRB-1 and SRB-2, respectively. Microbial community was regulated by filling substrates. Synergism between lignocellulosic decomposing bacteria and sulfate reducing bacteria played a vital role in lignocellulosic bioreactor treating AMD, in addition to fermentation liquid serving as effective electron donor.


Assuntos
Chlorobi , Microbiota , Biodegradação Ambiental , Sulfatos , Esterco , Áreas Alagadas , Reatores Biológicos/microbiologia , Bactérias , Ácidos , Sulfetos , Enxofre , Oxirredução
9.
Sci Total Environ ; 912: 169100, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38086483

RESUMO

Common reed (Phragmites australis) is a widely utilized plant for wetland restoration and construction, facing challenges posed by high salinity as a stressor. Among the diverse P. australis lineages, functional traits variation provides a valuable genetic resource for identifying salt-tolerant individuals. However, previous investigations on P. australis salt tolerance have been restricted to regional scales, hindering the identification of key functional traits associated with salt tolerance in natural habitats. To address this gap, we conducted a greenhouse experiment to assess and compare the salt tolerance of four major temperate P. australis lineages worldwide. We utilized the maximum quantum yield of photosystem II (Fv/Fm) as a health indicator, while final biomass and wilt status served as indicators of salt tolerance across lineages. Our findings revealed significant differentiation in plant functional traits among different lineages, but no significant effect of interaction between salinity and lineage on most traits. Correlation analyses between salt-tolerance indicators and functional traits in the control group indicated that biomass, leaf width, and relative leaf water content are potential predictors of salt tolerance. However, ecological strategies, physiological traits, and latitudinal origin did not exhibit significant correlations with salt tolerance. Our study provides valuable indicator traits for effectively screening salinity-tolerant genotypes of P. australis in field settings, and holds significant potential for enhancing wetland construction and biomass production in marginal lands.


Assuntos
Tolerância ao Sal , Áreas Alagadas , Humanos , Plantas , Poaceae , Fenótipo
10.
BMC Public Health ; 23(1): 2423, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053120

RESUMO

BACKGROUND AND AIM: The health implications of BMI and MetS in lactating women are significant. This study aims to investigate the relationship between risk of Mets in lactation and BMI in four stages: pre-pregnancy, prenatal period, 42 days postpartum, and current lactation. METHODS AND RESULTS: A total of 1870 Lactating Women within 2 years after delivery were included from "China Child and Lactating Mother Nutrition Health Surveillance (2016-2017)". Logistic regression model and Restricted cubic spline (RCS) were used to estimate the relationship between BMI and risk of MetS. ROC analysis was used to determine the threshold for the risk of MetS. Chain mediating effect analysis was used to verify the mediating effect. BMI of MetS group in all stages were higher than non-MetS group (P < 0.0001). There were significant positive correlations between BMI in each stage and ORs of MetS during lactation (P < 0.05). The best cut-off values for BMI in the four stages were 23.47, 30.49, 26.04 and 25.47 kg/m2. The non-linear spline test at BMI in 42 days postpartum, current and MetS in lactation was statistically significant (P non-linear = 0.0223, 0.0003). The mediation effect of all chains have to work through lactation BMI. The total indirect effect accounted for 80.95% of the total effect. CONCLUSIONS: The risk of MetS in lactating women is due to a high BMI base before pregnancy and postpartum. High BMI in all stages of pregnancy and postpartum were risk factors for MetS in lactation. BMI during lactation plays a key role in the risk of MetS.


Assuntos
Síndrome Metabólica , Feminino , Humanos , Gravidez , Índice de Massa Corporal , Aleitamento Materno , População do Leste Asiático , Lactação , Síndrome Metabólica/epidemiologia
11.
Front Immunol ; 14: 1326667, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155975

RESUMO

Lung cancer is a chronic wasting disease with insidious onset and long treatment cycle. Exosomes are specialized extracellular vesicles, at first exosomes were considered as a transporter of cellular metabolic wastes, but recently many studies have identified exosomes which contain a variety of biologically active substances that play a role in the regulation of cellular communication and physiological functions. Exosomes play an important role in the development of lung cancer and can promote metastasis through a variety of mechanisms. However, at the same time, researchers have also discovered that immune cells can also inhibit lung cancer through exosomes. In addition, researchers have discovered that some specific miRNAs in exosomes can be used as markers for early diagnosis of lung cancer. Engineering exosomes may be one of the strategies to enhance the clinical translational application of exosomes in the future, for example, strategies such as modifying exosomes to enhance targeting or utilizing exosomes as carriers for drug delivery have been explored. but more studies are needed to verify the safety and efficacy. This article reviews the latest research on exosomes in the field of lung cancer, from the mechanism of lung cancer development, the functions of immune cell-derived exosomes and tumor-derived exosomes, to the early diagnosis of lung cancer.


Assuntos
Exossomos , Vesículas Extracelulares , Neoplasias Pulmonares , MicroRNAs , Humanos , Neoplasias Pulmonares/patologia , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , MicroRNAs/metabolismo , Comunicação Celular
12.
Small ; : e2307446, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37941471

RESUMO

The zinc dendrite growth generally relies upon a "positive-feedback" mode, where the fast-grown tips receive higher current densities and ion fluxes. In this study, a self-limiting polyacrylamide (PAM) hydrogel that presents negative feedback to dendrite growth is developed. The monomers are purposefully polymerized at the dendrite tips, then the hydrogel reduces the local current density and ion flux by limiting zinc ion diffusion with abundant functional groups. As a consequence, the accumulation at the dendrite tips is restricted, and the (002) facets-oriented deposition is achieved. Moreover, the refined porous structure of the gel enhances Coulombic Efficiency by reducing water activity. Due to the synergistic effects, the zinc anodes perform an ultralong lifetime of 5100 h at 0.5 mA cm-2 and 1500 h at 5 mA cm-2 , which are among the best records for PAM-based gel electrolytes. Further, the hydrogel significantly prolongs the lifespan of zinc-ion batteries and capacitors by dozens of times. The developed in situ hydrogel presents a feasible and cost-effective way to commercialize zinc anodes and provides inspiration for future research on dendrite suppression using the negative-feedback mechanism.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38029370

RESUMO

With the pursuit of high energy and power density, the fast-charging capability of lithium-metal batteries has progressively been the primary focus of attention. To prevent the formation of lithium dendrites during fast charging, the ideal solid electrolyte interphase should be capable of concurrent fast Li+ transport and uniform nucleation sites; however, its construction in a facile manner remains a challenge. Here, as Al3+ has a higher charge and Al metal is lithiophilic, we tuned the Li+ solvation structure by introducing LiNO3 and aluminum ethoxide together, resulting in the dissolution of LiNO3 and the simultaneous generation of fast ionic conductor and lithiophilic sites. Consequently, our approach facilitated the deposition of lithium metal in a uniform and chunky way, even at a high current density. As a result, the Coulombic efficiency of the Li||Cu cell increased to over 99%. Moreover, the Li||LiFePO4 full cell demonstrated significantly enhanced cycling performance with a remarkable capacity retention of 94.5% at 4 C, far superior to the 46.1% capacity retention observed with the base electrolyte.

14.
J Sci Food Agric ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38029376

RESUMO

BACKGROUND: Rancidity causes unpleasant tastes and smells, and the degradation of fatty acids and natural antioxidants, so that an oil is unfit to be consumed. Natural antioxidants, including tocopherols, polyphenols (sesamol, canolol, ferulic acid, caffeic acid, etc.), ß-carotene, squalene and phytosterols, contribute to delay the oxidation of vegetable oils. However, studies on the combination of natural antioxidants to lengthen the shelf life of unsaturated fatty acid-rich blended oil have not been reported. RESULTS: All of the composite antioxidants had the potential to significantly improve the oxidation stability of blended oil. Blended oil G with 0.05 g kg-1 ß-carotene, 0.25 g kg-1 sesamol and 0.25 g kg-1 caffeic acid showed the best anti-autooxidation. It is also effective in improving the oxidative stability of vegetable oils containing various fatty acids. The oxidation stability index of the blended oil containing the optimum composition of natural antioxidants was 2.17-fold longer than that of the control sample. After the end of accelerated oxidation, the oil's peroxide value, p-anisidine value and total oxidation value were 6.59 times, 12.26 times and 6.65 times lower than those of the control sample, respectively. CONCLUSION: (1) The combination of natural antioxidants ß-carotene (0.05 g kg-1 ), sesamol (0.25 g kg-1 ) and caffeic acid (0.25 g kg-1 ) enhances the oxidative stability of unsaturated fatty acid-rich blended oils. (2) ß-Carotene is the main antioxidant in the early stages of oxidation. (3) Sesamol and caffeic acid are the main antioxidants in the middle and late stages of oxidation. © 2023 Society of Chemical Industry.

15.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796098

RESUMO

It is of great significance to study the mechanical behavior and permeability properties of hydrate-bearing sediments for a safe, efficient, and sustainable exploitation of hydrate. However, most of the studies conducted so far have focused only on a single stress field or seepage field, which is detached from practical engineering. In this paper, a new integrated experimental system (IES) was proposed, which realizes the coupling study of stress and seepage. The main body of IES is a triaxial subsystem and a seepage subsystem. The triaxial subsystem can realize in situ synthesis and triaxial shear of hydrate-bearing sediments (HBS). Stable seepage can be effectively formed using a constant pressure infusion pump and a back pressure valve. A series of shear-seepage coupling tests were carried out to verify the effectiveness of the IES and explore the stress-seepage coupling characteristics of HBS. The results show that stress has a significant influence on permeability, and its essence is the stress compression on the seepage channel. The stress-strain relationship, volume response, and permeability are related to each other. The permeability will be affected by the coupling of hydrate saturation (pore plugging), effective confining pressure (pore compression), and shear (fracture generation).

16.
Int Immunopharmacol ; 124(Pt B): 111005, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37804656

RESUMO

Human inactivated rabies virus (RABV) vaccines have been widely used worldwide over 30 years. The mechanisms of humoral immunity elicited by previously reported rabies candidate vaccines have been fully investigated, but little is known about the cellular immunity profiles. Herein, the recombinant RABV rLBNSE-IL-33 overexpressing the mouse interleukin-33 (IL-33) proliferated well in Neuro-2a cells and had no effects with the parent virus on growth kinetic in vitro and viral pathogenicity in mice. The rLBNSE-IL-33 experienced more antigen presentations by MHC-II on DCs and activated more CD4+ T cells which helped recruit more CD19+CD40+ B cells in blood and promote rapid and robust IgG1 antibodies responses at initial infection stage compared with the parent rLBNSE strain. Simultaneously, the rLBNSE-IL-33 were also presented by MHC-I to CD8+ T cells which contributed to produce high levels of IgG2a. The rLBNSE-IL-33 elicited significantly high levels of RABV-specific IFN-γ secreting memory CD4+ T cells, more RABV-specific IL-4 and IFN-γ secreting memory CD8+ T cells in spleens at early infection stage in mice. Altogether, overexpression of IL-33 in rLBNSE-IL-33 enhanced early antigen presentation, markedly promote CD4+, memory CD4+ and CD8+ T cells-mediated responses and provided a 100 % protection from lethal RABV challenge in mice. These findings provided an alternative novel therapy and vaccine strategy in future.


Assuntos
Vacina Antirrábica , Vírus da Raiva , Raiva , Humanos , Animais , Camundongos , Raiva/prevenção & controle , Interleucina-33 , Apresentação de Antígeno , Linfócitos T CD8-Positivos , Anticorpos Antivirais , Antígenos Virais , Imunidade Celular
17.
Materials (Basel) ; 16(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37687611

RESUMO

Cu-15Ni-8Sn alloy is the best choice to replace beryllium bronze alloy. This alloy has unparalleled application value in aerospace, ocean engineering, electronic information, equipment manufacturing, and other fields. However, the application of Cu-15Ni-8Sn alloy is challenged and limited because of a series of problems in its preparation and processing, such as easy segregation, difficult deformation, and discontinuous precipitation. It is an effective way to improve the comprehensive properties of Cu-15Ni-8Sn alloy using alloying design and process optimization to control the as-cast, deformed, and heat-treated microstructures. At present, it is a hot spot for scholars to study. In this paper, the grade generation, system evolution, and preparation technology development of Cu-15Ni-8Sn alloy are comprehensively reviewed. The phase transformation sequence of the Cu-15Ni-8Sn alloy is discussed. The influence of the type, amount, and existing form of alloying elements on the strength of Cu-15Ni-8Sn alloy and its mechanism are systematically summarized. Furthermore, the latest research progress on the effects of solid solution, cold deformation, and aging on the phase structure transformation and mechanical properties of Cu-15Ni-8Sn alloy is summarized. Finally, the future development trend of the Cu-15Ni-8Sn alloy is projected. The research results of this paper can provide a reference for the control of the microstructure and properties of high-performance Cu-15Ni-8Sn alloys used in key fields, as well as the optimization of the preparation process and alloy composition.

18.
Front Plant Sci ; 14: 1184584, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692418

RESUMO

Introduction: As precipitation patterns are predicted to become increasingly erratic, the functional maintenance of warm-temperate forests constitutes a key challenge for forest managers. In this study, 2-year-old Quercus acutissima seedlings were selected to elucidate the mechanisms whereby they respond to soil water fluctuations and the drought hardening effects on plant carbohydrate dynamics. Methods: Seedlings were trained under different soil water conditions for 2 months: drought (D), well-watered (W), 1-month drought and then 1-month well-watered (D-W), and 1-month well-watered and then 1-month drought (W-D). The functional traits involved in water- and carbon-use strategies were explored at the end of the hardening period. Compared with seedlings in group W, seedlings in groups D, D-W, and W-D had increased potential for carbon uptake (i.e., light saturated point, maximum ribulose-1,5-bisphosphate (RuBP) saturated rate, and electron transport rate) and water uptake (i.e., fine root-to-coarse root ratio) and downregulated growth and mitochondrial respiration to decrease carbon consumption. After water fluctuation hardening, we performed a successional dry-down experiment for 1 month to detect carbohydrate dynamics and explore the acclimation caused by prior hardening. Results and discussion: Our results revealed that there were more soluble sugars allocated in the leaves and more starch allocated in the stems and roots of seedlings hardened in the D, W-D, and D-W treatments than that of seedlings hardened in the W treatment. No significant changes in total non-structural carbohydrates were found. In addition, we found near-zero (seedlings trained by D and D-W treatments) or negative (seedlings trained by W-D treatment) growth of structural biomass at the end of the dry-down experiment, which was significantly lower than that of W-hardened seedlings. This suggests that there was a shift in allocation patterns between carbon storage and growth under recurrent soil drought, which can be strengthened by drought memory. We conclude that Q. acutissima seedlings adjusted water- and carbon-use strategies in response to water fluctuations, whereas stress memory can enhance their overall performance in reoccurring drought. Therefore, taking advantage of stress memory is a promising management strategy in forest nurseries, and drought-trained seedlings might be more suitable for afforestation practices in sites characterized by fluctuating soil water content, considering the ongoing global climatic changes.

19.
ACS Appl Mater Interfaces ; 15(28): 33682-33692, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37427424

RESUMO

Sodium-ion batteries (SIBs) have garnered extensive attentions in recent years as a low-cost alternative to lithium-ion batteries. However, achieving both high capacity and long cyclability in cathode materials remains a challenge for SIB commercialization. P3-type Na0.67Ni0.33Mn0.67O2 cathodes exhibit high capacity and prominent Na+ diffusion kinetics but suffer from serious capacity decay and structural deterioration due to stress accumulation and phase transformations upon cycling. In this work, a dual modification strategy with both morphology control and element doping is applied to modify the structure and optimize the properties of the P3-type Na0.67Ni0.33Mn0.67O2 cathode. The modified Na0.67Ni0.26Cu0.07Mn0.67O2 layered cathode with hollow porous microrod structure exhibits an excellent reversible capacity of 167.5 mAh g-1 at 150 mA g-1 and maintains a capacity above 95 mAh g-1 after 300 cycles at 750 mA g-1. For one thing, the specific morphology shortens the Na+ diffusion pathway and releases stress during cycling, leading to excellent rate performance and high cyclability. For another, Cu doping at the Ni site reduces the Na+ diffusion energy barrier and mitigates unfavorable phase transitions. This work demonstrates that the electrochemical performance of P3-type cathodes can be significantly improved by applying a dual modification strategy, resulting in reduced stress accumulation and optimized Na+ migration behavior for high-performance SIBs.

20.
Environ Sci Technol ; 57(26): 9884-9893, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37319319

RESUMO

Transition metal sulfides have exhibited remarkable advantages in gaseous elemental mercury (Hg0) capture under high SO2 atmosphere, whereas the weak thermal stability significantly inhibits their practical application. Herein, a novel N,N-dimethylformamide (DMF) insertion strategy via crystal growth engineering was developed to successfully enhance the Hg0 capture ability of MoS2 at an elevated temperature for the first time. The DMF-inserted MoS2 possesses an edge-enriched structure and an expanded interlayer spacing (9.8 Å) and can maintain structural stability at a temperature as high as 272 °C. The saturated Hg0 adsorption capacities of the DMF-inserted MoS2 were measured to be 46.91 mg·g-1 at 80 °C and 27.40 mg·g-1 at 160 °C under high SO2 atmosphere. The inserted DMF molecules chemically bond with MoS2, which prevents possible structural collapse at a high temperature. The strong interaction of DMF with MoS2 nanosheets facilitates the growth of abundant defects and edge sites and enhances the formation of Mo5+/Mo6+ and S22- species, thereby improving the Hg0 capture activity at a wide temperature range. Particularly, Mo atoms on the (100) plane represent the strongest active sites for Hg0 oxidation and adsorption. The molecule insertion strategy developed in this work provides new insights into the engineering of advanced environmental materials.


Assuntos
Mercúrio , Molibdênio , Dissulfetos , Sulfetos
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