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Since 2020, covalent organic frameworks (COFs) are emerging as robust catalysts for the photosynthesis of hydrogen peroxide (H2O2), benefiting from their distinct advantages. However, the current efficiency of H2O2 production and solar-to-chemical energy conversion efficiency (SCC) remain suboptimal due to various constraints in the reaction mechanism. Therefore, there is an imperative to propose efficiency improvement strategies to accelerate the development of this reaction system. This comprehensive review delineates recent advances, challenges, and strategies in utilizing COFs for photocatalytic H2O2 production. It explores the fundamentals and challenges (e.g., oxygen (O2) mass transfer rate, O2 adsorption capacity, response to sunlight, electron-hole separation efficiency, charge transfer efficiency, selectivity, and H2O2 desorption) associated with this process, as well as the advantages, applications, classification, and preparation strategies of COFs for this purpose. Various strategies to enhance the performance of COFs in H2O2 production are highlighted. The review aims to stimulate further advancements in utilizing COFs for photocatalytic H2O2 production and discusses potential prospects, challenges, and application areas in this field.
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The development of efficient and low-cost catalysts for cathodic oxygen reduction reaction (ORR) in Zn-air battery (ZAB) is a key factor in reducing costs and achieving industrialization. Here, a novel segregated CoNiPt alloy embedded in N-doped porous carbon with a nanoflowers (NFs)-like hierarchy structure is synthesized through pyrolyzing Hofmann-type metal-organic frameworks (MOFs). The unique hierarchical NFs structure exposes more active sites and facilitates the transportation of reaction intermediates, thus accelerating the reaction kinetics. Impressively, the resulting 15% CoNiPt@C NFs catalyst exhibits outstanding alkaline ORR activity with a half-wave potential of 0.93 V, and its mass activity is 7.5 times higher than that of commercial Pt/C catalyst, surpassing state-of-the-art noble metal-based catalysts. Furthermore, the assembled CoNiPt@C+RuO2 ZAB demonstrates a maximum power density of 172 mW cm-2 , which is superior to that of commercial Pt/C+RuO2 ZAB. Experimental results reveal that the intrinsic ORR mass activity is attributed to the synergistic interaction between oxygen defects and pyrrolic/graphitic N species, which optimizes the adsorption energy of the intermediate species in the ORR process and greatly enhances catalytic activity. This work provides a practical and feasible strategy for synthesizing cost-effective alkaline ORR catalysts by optimizing the electronic structure of MOF-derived catalysts.
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Solar-driven carbon dioxide (CO2) methanation holds significant research value in the context of carbon emission reduction and energy crisis. However, this eight-electron catalytic reaction presents substantial challenges in catalytic activity and selectivity. In this regard, researchers have conducted extensive exploration and achieved significant developments. This review provides an overview of the recent advances and challenges in efficient selective photocatalytic CO2 methanation. It begins by discussing the fundamental principles and challenges in detail, analyzing strategies for improving the efficiency of photocatalytic CO2 conversion to CH4 comprehensively. Subsequently, it outlines the recent applications and advanced characterization methods for photocatalytic CO2 methanation. Finally, this review highlights the prospects and opportunities in this area, aiming to inspire CO2 conversion into high-value CH4 and shed light on the research of catalytic mechanisms.
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Artificial photosynthesis for hydrogen peroxide (H2O2) presents a sustainable and environmentally friendly approach to generate clean fuel and chemicals. However, the catalytic activity is hindered by challenges such as severe charge recombination, insufficient active sites, and poor selectivity. Here, a robust strategy is proposed to regulate the electronic structure of catalyst by the collaborative effect of defect engineering and dopant. The well designed oxygen-doped CdS nanorods with S2- defects and Cd2+ 4d10 electron configuration (CdS-O,Sv) is successfully synthesized, and the Cd2+ active sites around S defects or oxygen atoms exhibit rapid charge separation, suppressed carrier recombination, and enhanced charge utilization. Consequently, a remarkable H2O2 production rate of 1.62 mmol g-1 h-1 under air conditions is acquired, with an apparent quantum yield (AQY) of 9.96% at a single wavelength of 450 nm. This work provides valuable insights into the synergistic effect between defect and doping on catalytic activity.
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The most challenging obstacle for photocatalysts to efficiently harvest solar energy is the sluggish surface redox reaction (e. g., oxygen evolution reaction, OER) kinetics, which is believed to originate from interface catalysis rather than the semiconductor photophysics. In this work, we developed a light-modulated transient photocurrent (LMTPC) method for investigating surface charge accumulation and reaction on the W-doped bismuth vanadate (W : BiVO4) photoanodes during photoelectrochemical water oxidation. Under illuminating conditions, the steady photocurrent corresponds to the charge transfer rate/kinetics, while the integration of photocurrent (I~t) spikes during the dark period is regarded as the charge density under illumination. Quantitative analysis of the surface hole densities and photocurrents at 0.6â V vs. reversible hydrogen electrode results in an interesting rate-law kinetics switch: a 3rd-order charge reaction behavior appeared on W : BiVO4, but a 2nd-order charge reaction occurred on W : BiVO4 surface modified with ultrathin Bi metal-organic-framework (Bi-MOF). Consequently, the photocurrent for water oxidation on W : BiVO4/Bi-MOF displayed a 50 % increment. The reaction kinetics alternation with new interface reconstruction is proposed for new mechanism understanding and/or high-performance photocatalytic applications.
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Objective: Glioblastoma is the most common and aggressive type of the central nervous system cancers. Although radiotherapy and chemotherapy are used in the treatment of glioblastoma, survival rates remain unsatisfactory. This study aimed to explore differentially expressed genes (DEGs) based on the survival prognosis of patients with glioblastoma and to establish a model for classifying patients into different risk groups for overall survival. Methods: DEGs from 160 tumor samples from patients with glioblastoma and 5 nontumor samples from other patients in The Cancer Genome Atlas database were identified. Functional enrichment analysis and a protein-protein interaction network were used to analyze the DEGs. The prognostic DEGs were identified by univariate Cox regression analysis. We split patient data from The Cancer Genome Atlas database into a high-risk group and a low-risk group as the training data set. Least absolute shrinkage and selection operator and multiple Cox regression were used to construct a prognostic risk model, which was validated in a test data set from The Cancer Genome Atlas database and was analyzed using external data sets from the Chinese Glioma Genome Atlas database and the GSE74187 and GSE83300 data sets. Furthermore, we constructed and validated a nomogram to predict survival of patients with glioblastoma. Results: A total of 3572 prognostic DEGs were identified. Functional analysis indicated that these DEGs were mainly involved in the cell cycle and focal adhesion. Least absolute shrinkage and selection operator regression identified 3 prognostic DEGs (EFEMP2, PTPRN, and POM121L9P), and we constructed a prognostic risk model. The receiver operating characteristic curve analysis showed that the areas under the curve were 0.83 for the training data set and 0.756 for the test data set. The predictive performance of the prognostic risk model was validated in the 3 external data sets. The nomogram showed that the prognostic risk model was reliable and that the accuracy of predicting survival in each patient was high. Conclusion: The prognostic risk model can effectively classify patients with glioblastoma into high-risk and low-risk groups in terms of overall survival rate, which may help select high-risk patients with glioblastoma for more intensive treatment.
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Single component white-light-emitting (SCWLE) materials are extremely desired in the field of solid-state lighting. However, pure-phosphorescent SCWLE has rarely been reported. Herein, one halogen-bonding-containing MOF [Cd(5-BIPA)(phen)] (1) has been synthesized, which shows efficient white-light emission originating from dual phosphorescence bands with different wavelengths and lifetimes. The fabrication of a phosphor-converted white-light-emitting diode device driven by pulsing current enables this MOF to be a promising phosphor.
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A broad light-harvesting range and efficient charge separation are two main ways to enhance the visible photocatalytic performance of semiconductors. Herein, an ionic porphyrin MOF [In(TPyP)]·(NO3) (1) (TPyP = 5,10,15,20-tetrakis(4-pyridyl)-21H,23H-porphyrin) was synthesized via in situ metalation. The orderly arranged porphyrin photosensitizer and the internal electric field between the MOF host and NO3- guests enable effective visible light response and electron-hole separation. Consequently, the as-synthesized MOF shows efficient photocatalytic degradation of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) organic pollutants. It can degrade 99.07% of RhB within only 20 minutes under visible light irradiation (λ > 420 nm) with a high chemical reaction rate constant of 0.2400 min-1. The photocatalytic activity of the title MOF is more efficient than those of other reported MOFs, COFs and even inorganic semiconductors. The reusability, energy level, band gap, charge distribution and main degradation mechanisms of the photocatalyst were well studied.
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Free amino acids (FAAs) are believed to play important roles in osmoregulation and buffer capacity in some aquatic animals, such as fishes. However, the potential roles of FAAs have not been systematically summarized and characterized until now. In the present study, the meta-analysis was conducted to investigate the relationships between FAAs and environmental salinities. Twenty published documents were included, accounting for 106 study cases. The effect sizes of total free amino acids (TFAAs), total essential amino acids (TEAAs), and total non-essential amino acids (TNEAAs) to salinity increase were calculated and determined by the restricted maximum likelihood (REML) method. It clearly showed that the elevated salinities significantly induced the contents of TFAAs, TEAAs, and TNEAAs at the ratio of 36%, 27%, and 29%, respectively. Faced to the salinity changes, the contents of FAAs in fishes under freshwater and seawater varied significantly, while the individuals under brackish water displayed relatively constant contents of FAAs. When salinity elevated, the contents of 17 amino acids in muscles significantly increased, suggesting the important roles of FAA metabolism in osmoregulation in fishes. The results also indicated that the effect sizes of TFAAs were positively related to the rates of salinity increases, and exhibited a significant quadratic linear relationship with temperatures. Additionally, the contents of FAAs also showed positive correlation with osmotic pressure, concentrations of plasma Na+, Cl-, and urea, implying their potential roles of FAAs in osmoregulation in fishes. These findings suggested that elevated salinities greatly induced the contents of FAAs in fishes, making a great contribution to maintaining the homeostasis of fishes in response to environmental salinity changes.
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Osmorregulação , Salinidade , Animais , Aminoácidos/metabolismo , Peixes/fisiologia , Brânquias/metabolismo , Osmorregulação/fisiologia , Equilíbrio Hidroeletrolítico/fisiologiaRESUMO
The development of efficient enzyme immobilization to promote their recyclability and activity is highly desirable. Zeolitic imidazolate framework-8 (ZIF-8) has been proved to be an effective platform for enzyme immobilization due to its easy preparation and biocompatibility. However, the intrinsic hydrophobic characteristic hinders its further development in this filed. Herein, a facile synthesis approach was developed to immobilize pepsin (PEP) on the ZIF-8 carrier by using Ni2+ ions as anchor (ZIF-8@PEP-Ni). By contrast, the direct coating of PEP on the surface of ZIF-8 (ZIF-8@PEP) generated significant conformational changes. Electrochemical oxygen evolution reaction (OER) was employed to study the catalytic activity of immobilized PEP. The ZIF-8@PEP-Ni composite attains remarkable OER performance with an ultralow overpotential of only 127â mV at 10â mA cm-2 , which is much lower than the 690 and 919â mV overpotential values of ZIF-8@PEP and PEP, respectively.
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Estruturas Metalorgânicas , Zeolitas , Estruturas Metalorgânicas/química , Zeolitas/química , Enzimas Imobilizadas/química , Pepsina A , ÍonsRESUMO
Thyroid carcinoma (THCA) has been increasing in incidence greater than other cancers. Long noncoding RNAs (lncRNAs) were reported to play crucial roles in THCA development. Our study aimed to explore the underlying mechanism of lncRNA thymidylate synthetase opposite strand RNA (TYMSOS) in THCA. TYMSOS and myristoylated alanine rich protein kinase C substrate like 1 (MARCKSL1) were upregulated whereas miR-130a-5p was downregulated in THCA cells and tissues. The results of loss-of-function assays showed that TYMSOS knockdown inhibited cell metastasis and epithelial-mesenchymal transition (EMT) in THCA. TYMSOS was primarily distributed in the cytoplasm of THCA cells, as shown by FISH assay. RNA pulldown and luciferase reporter assay further showed that TYMSOS binds with miR-130a-5p. Luciferase reporter assay also revealed that MARCKSL1 is targeted by miR-130a-5p. Rescue assay showed that the suppression of TYMSOS downregulation on THCA cell malignant behaviors was reversed by MARCKSL1 overexpression. Additionally, overexpressing MARCKSL1 offset the inhibition of TYMSOS downregu-lation on the PI3K/Akt signaling pathway. TYMSOS knockdown inhibits the growth of THCA tumors, as in vivo assays showed. Collectively, TYMSOS facilitates THCA progression by sponging miR-130a-5p and upregulating MARCKSL1 to activate the PI3K/Akt signaling pathway, providing new avenues for THCA treatment.
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Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Neoplasias da Glândula Tireoide , Humanos , Transição Epitelial-Mesenquimal/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Timidilato Sintase/genética , Timidilato Sintase/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Linhagem Celular Tumoral , RNA Longo não Codificante/genética , Transdução de Sinais/genética , Neoplasias Hepáticas/genética , Neoplasias da Glândula Tireoide/genética , Movimento Celular/genética , Proteínas de Ligação a Calmodulina/genética , Proteínas de Ligação a Calmodulina/metabolismoRESUMO
Renewable solar-driven carbon dioxide (CO2 ) conversion to highly valuable fuels is an economical and prospective strategy for both the energy crisis and ecological environment disorder. However, the selectivity and activity of current photocatalysts have great room for improvement due to the diversification and complexity of products. Here, an ambient-stable 2D/2D Co2 P@BP/g-C3 N4 heterojunction is designed for highly selective and efficient photocatalytic CO2 reduction reaction. The resulting Co2 P@BP/g-C3 N4 material has a remarkable conversion of CO2 to carbon monoxide (CO) with an ≈96% selectivity, coupled with a dramatically increased CO generation rate of 16.21 µmol g-1 h-1 , which is 5.4 times higher than pristine graphitic carbon nitride (g-C3 N4 ). In addition, this photocatalyst exhibits good ambient stability of black phosphorus (BP) without oxidation even over 180 days. The excellent photocatalytic selectivity and activity of Co2 P@BP/g-C3 N4 heterojunction are attributed to its lower energy barriers of *COOH, *CO, and *+CO in the process of CO2 reduction, coupled with rapid charge transfer at the heterointerfaces of BP/g-C3 N4 and Co2 P/BP. This is solidly verified by both density functional theory calculation and mechanism experiments. Therefore, this work holds great promise for an ambient-stable efficient and high selectivity photocatalyst in solar-driven CO2 conversion.
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R2PCF2H ligands and their R2P(O)CF2H precursors were synthesized from R2P(O)H with TMSCF3 by simply modulating the H2O concentration via deoxydifluoromethylation and difluoromethylation. The air sensitive R2PCF2H phosphines can be stabilized in Cu(I) clusters as ligands. Within these Cu(I) clusters, the Sonogashira cross-coupling reaction can proceed fast and efficiently using terminal alkynes and aryl iodides within 15 min at room temperature under air to give a variety of diaryl(alkyl)acetylenes in good yields (49 examples, yields of ≤99%). Six of the internal alkynes present in drug precursors can be obtained using this protocol in good yields. The mechanism is proposed on the basis of control experiments.
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Iodetos , Fosfinas , Alcinos , Catálise , Hidrocarbonetos Fluorados , Ligantes , Paládio , SilanosRESUMO
Herein, we developed an efficient and transition-metal-free multicomponent coupling reaction for the synthesis of aroyloxyl alkyl iodides. In the reaction among 2,4,6-triarylboroxines, THF, TMSCF3, LiOH, and NaI, five-component reactions could be precisely controlled by modulating CF3SO2Na, supplying one type of aroyloxyl alkyl iodides in moderate to high yields. The reaction exhibits good functional group tolerance and a wide substrate scope and can be easily transformed into other useful compounds. The mechanism is proposed on the basis of the control experiments.
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Iodetos , Hidrocarbonetos Fluorados , Iodetos/química , SilanosRESUMO
Presented here are the synthesis and gas-phase photocatalytic CO2 reduction of an anionic porous Zn-metalated porphyrin metal-organic framework (MOF) induced by an ionic liquid. The desired CO2 affinity and deep conduction band position of the MOF catalyst provide strong kinetic and thermodynamic advantages for photocatalytic CO2 to CH4 conversion with high selectivity (â¼70%) in H2O vapor.
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Chinese cabbage (Brassica rapa L. subsp. pekinensis) is one of the vegetables with the largest cultivated area in China and has been a great addition to the daily diet of Chinese people. A genetic map has been constructed in our previous study using the F2 population of two inbred lines of Chinese cabbage, namely "G291" (a hairy line) and "ZHB" (a hairless line), based on which a candidate gene related to trichome traits was identified on chromosome A06 with a phenotypic variance of 47%. A molecular marker was found to co-segregate with the trichome traits of the F2 population, which is in the 5'-flanking region of BrGL1, and a corresponding patent has been granted (NO. CN 108545775 B). Transcriptome analysis was carried out on the cotyledon, the first true leaf and the leaf closest to each inflorescence of F2 individuals of "G291 × ZHB" with or without trichomes, respectively. Ten pathways, including 189 DEGs, were identified to be involved in the development of trichomes in Chinese cabbage, which may be specifically related to the development of leaf trichomes. Most of the pathways were related to the biosynthesis of the secondary metabolites, which may help plants to adapt to the ever-changing external environment. DEGs also enriched the "plant-pathogen interaction" pathway, which is consistent with the conclusion that trichomes are related to the disease resistance of plants. Our study provides a basis for future research on the occurrence and development of trichomes in Chinese cabbage.
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Brassica rapa , Brassica , Humanos , Brassica rapa/genética , Tricomas/genética , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica , Brassica/genética , Folhas de Planta/genética , TranscriptomaRESUMO
Molecule-based crystalline materials with angle-dependent polarized emission have attracted considerable attention owing to their extensive applications in displays and anticounterfeiting. Herein, one anionic metal-organic framework (MOF) {[Zn2.5(µ3-OH)(NDC)2(HNDC)](HPIM)}n was constructed on the basis of an excellent photoactive ligand naphthalene-1,4-dicarboxylic acid (H2NDC). The protonated 2-propylimidazole (HPIM) guests residing in the nanochannels of MOF can be exchanged by a D-π-A cationic dye. The resulted host-guest system shows a rare example of ratiometric fluorescent polarizations and highly enhanced photoelectron performance in comparison with the pristine MOF.
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Metal-organic frameworks (MOFs) or coordination polymers (CPs)-based phosphorescence materials may provide a powerful route for photoelectric and optical recording devices. Herein, two phosphorescence ligands, iso-phthalic acid (IPA) and 2-methylimidazole (MIM), were selected to construct an nonporous CP {Zn(IPA)(MIM)2} (1) with a long-lived phosphorescence lifetime up to 552 ms. By the doping of Eosin Y (EY) dye molecules under an in situ process, the phosphorescence emission color of 1 can be expressly tuned from green to red. The light-harvesting range can also be vastly broadened from the UV to the visible region (550 nm). Photoelectron measurements reveal that the synergistic effect of bias voltage and illumination can greatly restrain electron-hole recombination for the generation of additional free charges.
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The relationship between the aggregation states of pyrene-based linkers and the photoluminescence/photoelectric performance was well studied by the formation of an anionic metal-organic framework, [BMI]2[Mg3(TBAPy)2(H2O)4]·2dioxane, which shows highly enhanced light-harvesting and photoelectric conversion efficiency by the encapsulation of D-π-A cation dyes.
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To characterize trace elements from inhalable particles and to estimate human health risks, airborne particles at an urban area of Ningbo city during haze and non-haze periods from November 2013 to May 2014 were collected by a nine-stage sampler. Seventeen trace elements (Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd and Pb) were measured by inductively coupled plasma mass spectrometry (ICP-MS). The concentrations of trace elements are in the ranges of 0.51 ng m-3 (Co) ~ 1.53 µg m-3 (K) for fine particles (Dp < 2.1 µm), and 1.07 ng m-3 (Co) ~ 4.96 µg m-3 (K) for coarse particles (2.1 µm < Dp < 9.0 µm) during the haze days, which are 1.15 -4.30 and 1.23- 7.83-fold as those of non-haze days, respectively. These elements could be divided into crustal elements (Na, Mg, Al, Ca, Ti, Fe and Co), non-crustal elements (Cu, Zn, Cd and Pb) and mixed elements (K, V, Cr, Mn, Ni and As) according to their enrichment factor values (EFs) and size distribution characteristics. Five emission sources of trace elements were identified by positive matrix factorization (PMF) modeling. The main sources of trace elements in fine particles are traffic emission (21.7%), coal combustion (23.6%) and biomass burning (32.1%); however, soil dust (61.5%), traffic emission (21.9%) and industry emissions (11.8%) are the main contributors for coarse particles. With the help of the multiple-path particle dosimetry (MPPD) model, it was found that deposition fractions of seventeen measured elements in the pulmonary region were in the range of 12.4%-15.1% and 6.66% -12.3% for the fine and coarse particles, respectively. The human health risk assessment (HRA) was employed according to the deposition concentration in the pulmonary region. The non-carcinogenic risk (HI) was below the safety limit (1.00). Nonetheless, the excess lifetime carcinogenic risk (ELCR) for adults increased by 2.42-fold during the haze days (2.06 × 10-5) as compared to that of non-haze days (8.50 × 10-6) in fine particles. Cr (VI) and As together contributed 96.5% and 96.3% of the integrated cancer risks during the haze and non-haze periods, respectively. Moreover, the related ELCR values in coarse particles were 36.7% and 62.8% of those in the fine particles for the non-haze period and haze period, respectively.