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1.
Int J Mol Sci ; 25(10)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38791463

RESUMO

Mitochondrial protein homeostasis is crucially regulated by protein degradation processes involving both mitochondrial proteases and cytosolic autophagy. However, it remains unclear how plant cells regulate autophagy in the scenario of lacking a major mitochondrial Lon1 protease. In this study, we observed a notable downregulation of core autophagy proteins in Arabidopsis Lon1 knockout mutant lon1-1 and lon1-2, supporting the alterations in the relative proportions of mitochondrial and vacuolar proteins over total proteins in the plant cells. To delve deeper into understanding the roles of the mitochondrial protease Lon1 and autophagy in maintaining mitochondrial protein homeostasis and plant development, we generated the lon1-2atg5-1 double mutant by incorporating the loss-of-function mutation of the autophagy core protein ATG5, known as atg5-1. The double mutant exhibited a blend of phenotypes, characterized by short plants and early senescence, mirroring those observed in the individual single mutants. Accordingly, distinct transcriptome alterations were evident in each of the single mutants, while the double mutant displayed a unique amalgamation of transcriptional responses. Heightened severity, particularly evident in reduced seed numbers and abnormal embryo development, was observed in the double mutant. Notably, aberrations in protein storage vacuoles (PSVs) and oil bodies were evident in the single and double mutants. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of genes concurrently downregulated in lon1-2, atg5-1, and lon1-2atg5-1 unveiled a significant suppression of genes associated with brassinosteroid (BR) biosynthesis and homeostasis. This downregulation likely contributes to the observed abnormalities in seed and embryo development in the mutants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Autofagia , Brassinosteroides , Regulação da Expressão Gênica de Plantas , Mitocôndrias , Sementes , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Autofagia/genética , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/metabolismo , Mitocôndrias/metabolismo , Brassinosteroides/metabolismo , Proteases Dependentes de ATP/metabolismo , Proteases Dependentes de ATP/genética , Mutação , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Regulação para Baixo , Fenótipo , Serina Endopeptidases
2.
Heliyon ; 10(3): e24500, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38317906

RESUMO

In recent years, the centrifugal casting material Cr35Ni45Nb has been widely used in cracking furnace tubes. The common failure forms in the service process are carburizing cracking, bending, bulging, creep cracking, thermal fatigue cracking, thermal shock cracking, and oxidation, among which the inner wall oxidation and carburization of cracking furnace tubes cause the largest proportion of material failure. In this paper, we will discuss the inner wall oxidation behavior of cracking furnace tubes and its influence on the lasting strength of the furnace tubes. Several groups of endurance tests were designed for service furnace tubes, and the oxidation characteristics, oxide film rupture damage, and its influence on the endurance life of furnace tubes in different service times were analyzed by means of XRD, SEM, and so on. The results show that the oxide layer of the furnace tube is divided into two layers, the outer layer is repeatedly destroyed and rebuilt. With the continuous evolution of material structure, its properties also deteriorate, and its tensile strength, yield strength, elongation, and durable life all decrease significantly.

3.
Sensors (Basel) ; 24(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38203136

RESUMO

Most single-object trackers currently employ either a convolutional neural network (CNN) or a vision transformer as the backbone for object tracking. In CNNs, convolutional operations excel at extracting local features but struggle to capture global representations. On the other hand, vision transformers utilize cascaded self-attention modules to capture long-range feature dependencies but may overlook local feature details. To address these limitations, we propose a target-tracking algorithm called CVTrack, which leverages a parallel dual-branch backbone network combining CNN and Transformer for feature extraction and fusion. Firstly, CVTrack utilizes a parallel dual-branch feature extraction network with CNN and transformer branches to extract local and global features from the input image. Through bidirectional information interaction channels, the local features from the CNN branch and the global features from the transformer branch are able to interact and fuse information effectively. Secondly, deep cross-correlation operations and transformer-based methods are employed to fuse the template and search region features, enabling comprehensive interaction between them. Subsequently, the fused features are fed into the prediction module to accomplish the object-tracking task. Our tracker achieves state-of-the-art performance on five benchmark datasets while maintaining real-time execution speed. Finally, we conduct ablation studies to demonstrate the efficacy of each module in the parallel dual-branch feature extraction backbone network.

4.
Heliyon ; 9(11): e22254, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38058623

RESUMO

In the domestic petrochemical industry, mounded storage tanks (MSTs) are widely used to store hazardous chemicals. The shell of the mounded storage tank is completely covered by soil to effectively mitigate the effect of the external environment and prevent thermal-expansion-induced explosion of the stored material. Because mounded storage tanks are mostly underground, they are highly safe, provide effective land utilization, and are highly energy efficient. Furthermore, the impact radius in case of an explosion is less than that of aboveground tanks. However, adequate regulations and standards for safety management are yet to be established. This study established a novel method for the integrity management of mounded storage tanks through database construction, risk assessment, applicability monitoring, and testing. At the same time, the risk assessment method for mounded storage tank characteristics is constructed for the first time.

5.
Sci Rep ; 13(1): 18592, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37903981

RESUMO

Cracking furnaces, operating under high temperatures and in a hydrocarbon medium, subject their tubes to complex stresses such as internal pressure, self-weight, fatigue, and thermal shock during start-up and shutdown. As a result, these furnace tubes frequently experience failures characterized by cracks and corrosion perforation. The high-temperature environment, constantly evolving structure of the tubes, and the close arrangement of the cracks within the tube box hinder detecting the cracks using conventional single-detection methods is challenging. This paper breaks through the limitations of the traditional single detection method and studies the effectiveness of the combination of ultrasonic-guided wave and low-frequency electromagnetic detection methods. The experiment was carried out by deliberately making cracks and thinning defects caused by corrosion on the cracking furnace tube of Cr35Ni45Nb after two years of service. The experimental results show that the ultrasonic guided wave detection technology can quickly detect the defects running through the whole furnace tube and effectively identify the manufacturing defects. On the other hand, low-frequency electromagnetic detection makes it possible to scan suspicious local defects and make qualitative and quantitative analyses of defect signals. The combination of ultrasonic guided wave and low-frequency electromagnetic detection can realize the rapid location and comprehensive qualitative and quantitative analysis of furnace tube defects, thus making up for the defects missed detection caused by the lack of effectiveness of single detection and the resulting safety problems. The research results have great popularization value in practical engineering applications.

6.
Front Microbiol ; 14: 1111965, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36876084

RESUMO

Peanut stem rot, caused by Sclerotium rolfsii, considerably affects crop productivity. Application of chemical fungicides harms the environment and induces drug resistance. Biological agents are valid and eco-friendly alternatives to chemical fungicides. Bacillus spp. are important biocontrol agents that are now widely used against several plant diseases. This study aimed to evaluate the efficacy and mechanism of a potential biocontrol agent Bacillus sp. for controlling peanut stem rot caused by S. rolfsii. Here, we isolated a strain of Bacillus from pig biogas slurry that considerably inhibits the radial growth of S. rolfsii. The strain CB13 was identified as Bacillus velezensis on the basis of morphological, physiological, biochemical characteristics and phylogenetic trees based on the 16S rDNA and gyrA, gyrB, and rpoB gene sequences. The biocontrol efficacy of CB13 was evaluated on the basis of colonization ability, induction of defense enzyme activity, and soil microbial diversity. The control efficiencies of B. velezensis CB13-impregnated seeds in four pot experiments were 65.44, 73.33, 85.13, and 94.92%. Root colonization was confirmed through green fluorescent protein (GFP)-tagging experiments. The CB13-GFP strain was detected in peanut root and rhizosphere soil, at 104 and 108 CFU/g, respectively, after 50 days. Furthermore, B. velezensis CB13 enhanced the defense response against S. rolfsii infection by inducing defense enzyme activity. MiSeq sequencing revealed a shift in the rhizosphere bacterial and fungal communities in peanuts treated with B. velezensis CB13. Specifically, the treatment enhanced disease resistance by increasing the diversity of soil bacterial communities in peanut roots, increasing the abundance of beneficial communities, and promoting soil fertility. Additionally, real-time quantitative polymerase chain reaction results showed that B. velezensis CB13 stably colonized or increased the content of Bacillus spp. in the soil and effectively inhibited S. rolfsii proliferation in soil. These findings indicate that B. velezensis CB13 is a promising agent for the biocontrol of peanut stem rot.

7.
J Ethnopharmacol ; 309: 116330, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-36868438

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Clinopodium chinense Kuntze (CC), traditional Chinese medicine with anti-inflammatory, anti-diarrheal, and hemostatic activities, has been used to treat dysentery and bleeding diseases for thousands of years, which are similar to the symptoms of ulcerative colitis (UC). AIM OF THE STUDY: To obtain a novel treatment for UC, an integrated strategy was developed in this study to investigate the effect and mechanism of CC against UC. MATERIALS AND METHODS: The chemical characterization of CC was scanned by UPLC-MS/MS. Network pharmacology analysis was performed to predict the active ingredients and pharmacological mechanisms of CC against UC. Further, the results of network pharmacology were validated using LPS-induced RAW 264.7 cells and DSS-induced UC mice. The production of pro-inflammatory mediators and biochemical parameters was tested using the ELISA kits. The expression of NF-κB, COX-2, and iNOS proteins was evaluated using Western blot analysis. Body weight, disease activity index, colon length, histopathological examination, and metabolomics analysis in colon tissues were carried out to confirm the effect and mechanism of CC. RESULTS: Based on the chemical characterization and literature collection, a rich database of ingredients in CC was constructed. Network pharmacology analysis provided five core components as well as revealed that the mechanism of CC against UC was highly related to inflammation, especially the NF-κB signaling pathway. In vitro experiments showed CC could inhibit inflammation by LPS-TLR4-NF-κB-iNOS/COX-2 signaling pathway in RAW264.7 cells. Meanwhile, in vivo experimental results proved that CC significantly alleviated pathological features with increased body weight and colonic length, decreased DAI and oxidative damage, as well as mediated inflammatory factors like NO, PGE2, IL-6, IL-10, and TNF-ɑ. In addition, colon metabolomics analysis revealed CC could restore the abnormal endogenous metabolite levels in UC. 18 screened biomarkers were further enriched in four pathways including Arachidonic acid metabolism, Histidine metabolism, Alanine, aspartate and glutamate metabolism as well as the Pentose phosphate pathway. CONCLUSION: This study demonstrates that CC could alleviate UC by reducing systematic inflammation and regulating metabolism, which is beneficial for providing scientific data for the development of UC treatment.


Assuntos
Colite Ulcerativa , Colite , Camundongos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , NF-kappa B/metabolismo , Sulfato de Dextrana/toxicidade , Ciclo-Oxigenase 2/metabolismo , Cromatografia Líquida , Lipopolissacarídeos/farmacologia , Espectrometria de Massas em Tandem , Inflamação/patologia , Colo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Colite/metabolismo
8.
Nat Prod Res ; 37(2): 348-353, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34396839

RESUMO

The phytochemical investigation on the leaves of Psidium guajava Linn. led to the isolation and identification of 18 compounds, including six guavinoside (1-6), four flavonoids (7-10), eight triterpenoids (11-17) and one lignans (18). All chemical structures were elucidated via NMR spectroscopic methods, and further supported by comparison with literature data. Compounds 12, 14, 16 and 18 was isolated from the Myrtaceae family for the first time. The chemotaxonomic significance of these compounds was also discussed based on their structure types, as well as compounds-genus/family network analysis. The results showed that there were close chemotaxonomic relationships among the Myrtaceae, Asteraceae, and Lamiaceae families. Guavinosides A-F could be considered as valuable chemotaxonomic markers of Myrtaceae family, while guavinosides C-F might serve as chemotaxonomic markers for distinguishing the P. guajava.


Assuntos
Myrtaceae , Psidium , Humanos , Psidium/química , Folhas de Planta/química , Extratos Vegetais/química , Flavonoides/química
9.
J Econ Entomol ; 115(6): 1859-1868, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36124625

RESUMO

Antheraea pernyi Guérin-Méneville (Lepidoptera: Saturniidae) is of high economic value as a source of silk, food, and bioactive substances with medicinal properties. A. pernyi larvae are prone to A. pernyi vomit disease (AVD), which results in substantial economic losses during cultivation; however, the relationship between AVD and A. pernyi gut microbiota remains unclear. Here, we investigated the bacterial community in the midgut and feces of A. pernyi larvae with and without AVD using 16S rRNA gene sequencing with Illumina MiSeq technology. Compared with healthy larvae, intestinal bacterial diversity and community richness increased and decreased in larvae with mild and severe AVD, respectively. In addition, the proportion of gut Enterobacter Hormaeche and Edwards(Enterobacteriales: Enterobacteriaceae) and Enterococcus Thiercelin and Jouhaud (Lactobacillales: Enterococcaceae) was higher and lower, respectively, in larvae with mild AVD than those in healthy larvae. A. pernyi vomit disease infection significantly increased the genera with abundance <1%. In the gut of larvae with severe AVD, the proportion of Turicibacter Bosshard et al. (Erysipelotrichales: Turicibacteraceae) increased significantly to 81.53-99.92%, whereas that of Enterobacter decreased compared with healthy larvae. However, the diversity of fecal bacteria was similar between healthy larvae and those with mild AVD. Overall, the findings demonstrate that intestinal microflora in A. pernyi larvae are altered by AVD infection and may cause secondary bacterial infection. This is the first report of the presence of Turicibacter in the intestinal tract of lepidopterans.


Assuntos
Microbioma Gastrointestinal , Mariposas , Animais , Larva/genética , RNA Ribossômico 16S/genética , Mariposas/genética , Seda , Bactérias/genética
10.
Chem Biodivers ; 19(7): e202200383, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35739622

RESUMO

We used UV-guided method to isolate and identify 12 secondary metabolites from Meehania fargesii var. Radicans for the first time, including eight triterpenoids (1-8), two phenylpropanoid derivatives (9-10) and two flavone glycosides (11-12). Their structures were identified by NMR spectroscopic methods, as well as literature comparison. The identified compounds and positive drugs (amoxicillin, omeprazole and clarithromycin) were further analyzed for their in silico docking interactions with HtrA using igemdock. Docking studies revealed the high binding affinity of phytochemicals at significant sites with HtrA, compounds 11 and 12 exhibiting stronger binding ability than standard drug, 1 and 3-10 demonstrating comparable docking capacity to standard drugs. The chemotaxonomic relationships were carried out to exploring the possibilities of other medicinal plants against Hp-induced gastric carcinoma. The results demonstrated there are closely chemotaxonomic similarity among several genera of the Lamiaceae family as well as among Lamiaceae, Actinidiaceae and Rosaceae families, indicating a similar chemical compositions and anti-Hp-induces gastric carcinoma activity among them.


Assuntos
Carcinoma , Infecções por Helicobacter , Helicobacter pylori , Lamiaceae , Antibacterianos/farmacologia , Carcinoma/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Humanos , Simulação de Acoplamento Molecular , Compostos Fitoquímicos/farmacologia
11.
Neurochem Res ; 47(8): 2198-2210, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35513760

RESUMO

The antiknock additive methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic manganese(Mn) compound. Mn neurotoxicity caused by occupational Mn exposure (mostly inorganic MnCl2) is associated with motor and cognitive disturbances, referred to as Manganism. However, the impact of environmentally relevant Mn exposure on MMT-induced Manganism is poorly understood. In this investigation, we studied the effects of MMT on motor function and brain structure, and compared its effects with those of inorganic MnCl2. After adaptive feeding for 7 days, male and female Sprague-Dawley (SD) rats in the MMT-treated groups and positive control group were treated for 8 weeks with MMT (1, 2 and 4 mg/kg/i.g.) or MnCl2·4H2O (200 mg/kg/i.g.). Mn content in blood, liver, spleen and distinct brain regions was determined by inductively coupled plasma-mass spectrometer (ICP-MS). We found that MMT and MnCl2 exposure led to slower body-weight-gain in female rats, impaired motor and balance function and spatial learning and memory both in male and female rats. HE staining showed that MMT and MnCl2 led to altered structure of the substantia nigra pars compacta (SNpc), and Nissl staining corroborated MMT's propensity to damage the SNpc both in male and female rat. In addition, Immunostaining of the SNpc showed decreased TH-positive neurons in MMT- and MnCl2-treated rats, concomitant with Iba1 activation in microglia. Moreover, no statistically significant difference was noted between the rats in the H-MMT and MnCl2 groups. In summary, these findings suggest that MMT and MnCl2 exposure cause ultrastructural changes in the SNpc neurons culminating in altered motor behavior and cognition, suggesting that altered SNpc structure and function may underline the motor and cognitive deficits inherent to Manganism, and accounting for MMT and MnCl2's manifestations of atypical parkinsonism.


Assuntos
Intoxicação por Manganês , Manganês , Animais , Cloretos , Feminino , Masculino , Manganês/toxicidade , Compostos de Manganês , Ratos , Ratos Sprague-Dawley , Substância Negra
12.
Pest Manag Sci ; 78(6): 2693-2703, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35388600

RESUMO

BACKGROUND: The black carabid beetle Calosoma maximoviczi is a successful predator that serves as both a beneficial insect and a severe threat to economic herbivores. Its hunting technique relies heavily on olfaction, but the underlying mechanism has not been studied. Here, we report the electrophysiological, ecological and molecular traits of bioactive components identified from a comprehensive panel of natural odorants in the beetle-prey-plant system. The aim of this work was to investigate olfactory perceptions and their influence on the behaviours of C. maximoviczi. RESULTS: Among the 200 identified volatiles, 18 were concentrated in beetle and prey samples, and 14 were concentrated in plants. Insect feeding damage to plants led to a shift in the emission fingerprint. Twelve volatiles were selected using successive electrophysiological tests. Field trials showed that significant sex differences existed when trapping with a single chemical or chemical mixture. Expression profiles indicated that sex-biased catches were related to the expression of 15 annotated CmaxOBPs and 40 CmaxORs across 12 chemosensory organs. In silico evaluations were conducted with 16 CmaxORs using modelling and docking. Better recognition was predicted for the pairs CmaxOR5-(Z)-3-hexenyl acetate, CmaxOR6-ß-caryophyllene, CmaxOR18-(E)-ß-ocimene and CmaxOR18-tetradecane, with higher binding affinity and a suitable binding pocket. Lastly, 168Y in CmaxOR6 and 142Y in CmaxOR18 were predicted as key amino acid residues for binding ß-caryophyllene and tetradecane, respectively. CONCLUSION: This work provides an example pipeline for de novo investigation in C. maximoviczi baits and the underlying olfactory perceptions. The results will benefit the future development of trapping-based integrated pest management strategies and the deorphanization of odorant receptors in ground beetles. © 2022 Society of Chemical Industry.


Assuntos
Besouros , Receptores Odorantes , Animais , Besouros/genética , Besouros/metabolismo , Proteínas de Insetos/metabolismo , Odorantes , Plantas/metabolismo , Receptores Odorantes/química , Olfato
13.
Phys Chem Chem Phys ; 24(3): 1760-1769, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34985063

RESUMO

Sulfonated N-heterocyclic poly(aryl ether) proton-exchange membranes have potential applications in the fuel-cell field due to their favorable proton conduction capacity and stability. This paper investigates the changes in mass and performance decay, such as proton conduction and mechanical strength, of sulfonated poly(ether ether ketone)s (SPEEKs) and three sulfonated N-heterocyclic poly(aryl ether ketone) (SPPEK, SPBPEK-P-8, and SPPEKK-P) membranes in Fenton's oxidative experiment. The SPEEK membrane exhibited the worst oxidative stability. The oxidative stability of the SPPEK membrane is enhanced due to the introduction of phthalazinone units in the chains. The SPPEKK-P and SPBPEK-P-8 membranes exhibit better radical tolerance than the SPPEK membrane, with proton conductivity retention rates of 66% and 73% for 1 h oxidative treatment, respectively. In addition, the molecular chains of SPPEKK-P and SPBPEK-P-8 exhibit relatively little disruption. The pendant benzenesulfonic groups enhance the steric effects for reducing radical attacks on the ether bonds and reduce the hydration of molecular chains. The introduction of phthalazinone units decreases the rupture points in the main chain. Therefore, the radical tolerance of the membranes is improved. These results provide a reference for the design of highly stable sulfonated heterocyclic poly(aryl ether) membranes.

14.
Environ Sci Pollut Res Int ; 29(21): 31198-31216, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35001270

RESUMO

To assess the characteristics of household carbon emissions per capita (HCPC), this paper divided China's provinces into 4 groups based on the decoupling relationship between household consumption and related emissions. This classification helped to analyze the correlation and reflected the decoupling status between carbon emissions and household consumption and explored the effect of consumption growth on carbon emissions. Then, according to logarithmic mean divisia index (LMDI) model, HCPC in China's provinces was decomposed into four drivers including carbon coefficient, energy structure, energy consumption, and population structure effect. Through multi-regional (M-R) analysis, temporal evolution and spatial differences of these four drivers in both national and provincial level were studied. This comparison method introduced temporal and spatial decomposition results into the same framework, which may provide a new perspective for analyzing carbon emission trends. The results showed that (a) the HCPC in all 30 provinces increased significantly especially in Inner Mongolia, Tianjin, Xinjiang, Heilongjiang, and Beijing. Energy consumption effect was the leading factor promoting HCPC growth. Energy structure and population structure also promoted HCPC growth slightly, and carbon coefficient was the effect which had inhibitory effect on HCPC growth at regional level. (b) Spatial differences of HCPC between regions narrowed during this period. This is mainly due to the rapid growth of HCPC in region IV. Energy consumption effect was the dominant factor for the spatial differences. Based on the results, this paper proposed to adopt more effective measures to improve energy efficiency, develop clean energy, and optimize energy structure, especially in the provinces with faster growth in carbon emissions.


Assuntos
Carbono , Desenvolvimento Econômico , Pequim , Carbono/análise , Dióxido de Carbono/análise , China
15.
JACS Au ; 2(1): 150-158, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35098231

RESUMO

Tip-based photoemission spectroscopic techniques have now achieved subnanometer resolution that allows visualization of the chemical structure and even the ground-state vibrational modes of a single molecule. However, the ability to visualize the interplay between electronic and nuclear motions of excited states, i.e., vibronic couplings, is yet to be explored. Herein, we theoretically propose a new technique, namely, tip-enhanced fluorescence excitation (TEFE). TEFE takes advantage of the highly confined plasmonic field and thus can offer a possibility to directly visualize the vibronic effect of a single molecule in real space for arbitrary excited states in a given energy window. Numerical simulations for a single porphine molecule confirm that vibronic couplings originating from Herzberg-Teller (HT) active modes can be visually identified. TEFE further enables high-order vibrational transitions that are normally suppressed in the other plasmon-based processes. Images of the combination vibrational transitions have the same pattern as that of their parental HT active mode's fundamental transition, providing a direct protocol for measurements of the activity of Franck-Condon modes of selected excited states. These findings strongly suggest that TEFE is a powerful strategy to identify the involvement of molecular moieties in the complicated electron-nuclear interactions of the excited states at the single-molecule level.

16.
Clean Technol Environ Policy ; 24(4): 1219-1240, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34849112

RESUMO

Energy and environmental policies are important methods for the government to restrain carbon emissions growth. Identifying the potential dynamic trends of China's carbon emissions under different scenarios has important reference significance for the government's policy implementation. This paper firstly predicted China's carbon emissions from 2017 to 2040 based on three energy transition scenarios at the industrial level. Then, Logarithmic Mean Divisia Index decomposition model was applied to evaluate the driving forces of emissions changes during 1997-2040. Finally, the Spatial-Temporal Logarithmic Mean Divisia Index model was used to explore the emissions reduction potential and the potential reduction path at provincial level. The results showed that (1) as the reduction in energy intensity cannot offset the growth of industrial scale, the carbon emissions of all industries have shown an increasing trend from 1997 to 2017; (2) In the current policies scenario, China's carbon emissions cannot reach the peak before 2040. And only in the sustainable development scenario, the carbon emissions of the three industries will all reach the peaks before 2030. And the development of non-fossil energy will reduce carbon emissions by more than 30%; (3) Hebei, Shanxi, Inner Mongolia, Ningxia, and Heilongjiang are key provinces and improving energy efficiency of the secondary industry is a potential way to promote carbon emissions reduction. GRAPHICAL ABSTRACT: The framework and main content of this paper. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10098-021-02240-7.

17.
J Phys Chem Lett ; 12(37): 9094-9099, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34520213

RESUMO

Controlling the photon emission property of a single molecule is an important goal for nano-optics. We propose here a new mechanism for a single-molecule optical switch that utilizes the in situ electric field (EF) in biased metallic nanojunctions to control photon emission of molecules with through-space charge transfer (TSCT) excited states. The EF-induced Stark effect is capable of flipping the order of the bright noncharge transfer state and dark TSCT state, resulting in the anticipated switching behavior. The proposed mechanism was theoretically verified by scanning tunneling microscope-induced electroluminescence from a naphtalenediimide cyclophane molecule under experimentally accessible conditions. Simulations show that the proposed switching effect can be obtained by changing either bias polarity, which alters the polarization of the field, or tip-height, which affects the magnitude of the field. Our finding indicates that the in situ EF could play an important role in the design of optoelectronic molecular devices.

18.
ACS Nano ; 15(9): 15027-15038, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34469124

RESUMO

Lithium-sulfur (Li-S) batteries have attracted a great deal of attention for the next-generation energy storage devices due to their inherently high theoretical energy density, high natural abundance, and low cost. However, the dissolution of polysulfides in electrolytes and their undesirable shuttle behavior lead to poor cycling performance, which obstructs practical application. Herein, we report a dual-sulfur-fixing mechanism of epoxy/allyl compound/sulfur system to prepare poly(sulfur-random-4-vinyl-1,2-epoxycyclohexane) (SVE) copolymers as powerful cathode materials. Benefiting from the stable C-S bond and a uniform distribution of ultrafine Li2S/S8 in the SVE-based polymer matrix, the SVE electrodes exerted an embedding effect to reduce polysulfides migration. The thiosulfate/polythionate protective layer derived from the terminal hydroxyl group of SVE also ensured the cycle stability of SVE electrodes during cycling. As a result, optimized SVE electrodes deliver a high reversible specific capacity of 1248 mA h g-1 at rates of 0.1 C, together with a stable cycling performance of no capacity decay per cycle over more than 400 cycles. This work provides an effective strategy for the practical application of organosulfur polymers Li-S batteries and inspires the exploration of the reaction mechanism of epoxy/allyl compound/sulfur system.

19.
Sci Total Environ ; 773: 145026, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582330

RESUMO

CO2 emissions from electricity generation (CEE) in China increased from 935 Mt to 3511 Mt during the period 1997-2017, ignoring a slight decline from 2013 to 2015. To identify what resulted in this pattern and how to peak China's CEE in the future, this study first quantitatively evaluated the drivers of CEE. Then, considering both the energy transition and thermal power generation efficiency (TPGE) could make sense in CEE reduction, based on historical data from China's 30 provinces during 1997-2017, we established twelve scenarios, which were hybrids of four electricity mix scenarios (refer to International Energy Agency (IEA) and China National Renewable Energy Centre (CNRE)) and three TPGE scenarios (business-as-usual (BAU), median scenario, and best-available-technology (BAT)), to explore the impacts of energy transition and regional convergence in TPGE on CEE until 2040. The BAU scenario assumes the TPGE in all provinces develops as historical trends, while the median scenario and BAT scenario represent a form of weak and strong regional convergence in TPGE across provinces, respectively. The decomposition results showed that TPGE was a dominator in emissions reduction, followed by the share of renewables in electricity generation. The scenario analysis indicated that when the electricity mix changes with IEA's Current Policies scenario, the decline in CEE will be not persistent after 2017 unless a strong regional convergence in TPGE occurs. Moreover, under BAT scenario, with any case of electricity mix the CEE in 2040 is 31-54% lower than that under BAU scenario. The results also showed that more ambitious targets for developing low-carbon technologies could help the rapid decarbonization of China's electricity sector.

20.
Environ Sci Pollut Res Int ; 28(3): 3703-3718, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32926275

RESUMO

To evaluate the relationship between coal-related carbon emissions (CCE) and economic growth, this paper analyzed the decoupling relationship between CCE and economic growth from national and provincial perspectives during period 1997-2016 through Tapio Decoupling Index. Then, to recognize its spatial characteristics during 1997-2016, gravity model was adopted to study the geographical changes of CCE. Finally, to identify the changes of (CCE) in China and reveal its internal driving forces, this paper employs the logarithmic mean Divisia index (LMDI) decomposition analysis to decompose decoupling indicator into six effects including emission factors, energy intensity, fossil energy structure, energy consumption structure, activity, and population at national and provincial levels. The results reflect that (1) CCE of China rose by 168.37% from 1997 to 2016, and reached the peak of 7948.43 Mton in 2013. The center of gravity has shifted from (114.64 E, 34.70 N) to (113.48 E, 35.06 N). (2) The decoupling curve showed an inverted "U" shape. The economic growth of 18 provinces has achieved a strong decoupling from CCE by 2016. Only Xinjiang, Shanxi, and Shaanxi's economic growth has increased the dependence on CCE. (3) Activity and energy intensity effects were the dominant factors driving and curbing the increase of decoupling indicator respectively.


Assuntos
Carbono , Desenvolvimento Econômico , Carbono/análise , Dióxido de Carbono/análise , China , Carvão Mineral
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