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1.
Chem Sci ; 15(32): 12973-12982, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39148777

RESUMO

The practical application of α-Fe2O3 in water splitting is hindered by significant charge recombination and slow water oxidation. To address this issue, a CoSAs-g-C3N4/Fe2O3 (CoSAs: cobalt single atoms) photoanode was fabricated in this study through the co-modification of CoSAs and g-C3N4 to enhance photoelectrochemical (PEC) water splitting. The coupling between g-C3N4 and α-Fe2O3 resulted in the formation of a heterojunction, which provided a strong built-in electric field and an additional driving force to mitigate charge recombination. Moreover, g-C3N4 served as a suitable carrier for single atoms, which effectively anchored CoSAs through N/C coordination. The highly dispersed CoSAs provided abundant active sites, which further promoted surface holes extraction and oxidation kinetics, resulting in higher PEC performance and photostability. This study indicates the benefits of these collaborative strategies and provides more efficient designs for solar energy conversion in PEC systems.

2.
Talanta ; 279: 126629, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39106649

RESUMO

Considering the excellent properties such as deep tissue penetration, high signal-to-noise ratio, and in-situ recharge and reactivation, near-infrared luminescence long afterglow nanoparticles show considerable promise for biological application, especially in multifunctional imaging, targeting, and synergistic therapeutic. In this paper, Zn3Ga4GeO11: 0.1 % Cr3+, 1 % Yb3+, 0.1 % Tm3+@Ag-FA (ZGGO@Ag-FA, ZGA-FA) nanoparticles were synthesized by in-situ growth of Ag nanoparticles on the surface of long afterglow nanoparticles, and further modified with folic acid. Through precise adjustments, the luminescent properties of ZnGa2O4 were enhanced and notably boosted the photothermal effect of Ag by leveraging the upconversion emission of ZGGO, with a photothermal conversion efficiency reaching about 59.9 %. The ZGA-FA nanoparticles are ultra-small, measuring less than 50 nm. The modification with folic acid provides the ZGA-FA nanoparticles with excellent tumor-targeting capabilities, demonstrating effective enrichment and retention in tumor tissues, thus enabling long-term imaging and therapy through in vivo re-excitation. Due to its stable photothermal effect, outstanding near-infrared (NIR) afterglow imaging, and red-light charged characteristics, combined with effective tumor-targeting abilities, the therapeutic strategy proposed by this study has significant potential for clinical applications.

3.
Nanomaterials (Basel) ; 14(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39120384

RESUMO

Mechanoluminescent (ML) materials can exhibit visible-to-near-infrared mechanoluminescence when responding to the fracture or deformation of a solid under mechanical stimulation. Transforming mechanical energy into light demonstrates promising applications in terms of visual mechanical sensing. In this work, we synthesized the phosphor CaZnOS:Tb3+, Sm3+, which exhibited intense and tunable multicolor mechanoluminescence without pre-irradiation. Intense green ML materials were obtained by doping Tb3+ with different concentrations. Tunable multicolor mechanoluminescence (such as green, yellow-green, and orange-red) could be realized by combining green emission (about 542 nm), attributed to Tb3+, and red emission (about 600 nm) generated from the Sm3+ in the CaZnOS substrate. The tunable multicolor ML materials CaZnOS:Tb3+, Sm3+ exhibited intense luminance and recoverable mechanoluminescence when responding to mechanical stimulation. Benefiting from the excellent ML performance and multicolor tunability in CaZnOS:Tb3+, Sm3+, we mixed the phosphor with PDMS and a curing agent to explore its practical application. An application for visual mechanical sensing was designed for handwriting identification. By taking a time-lapsed shot while writing, we easily obtained images of the writer's handwriting. The images of the ML intensity were acquired by using specific software to transform the shooting data. We could easily distinguish people's handwriting through analyzing the different ML performances.

4.
Dalton Trans ; 53(28): 11850-11857, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38949446

RESUMO

Lanthanide metal-organic frameworks (Ln-MOFs) have unique advantages in sensing due to their excellent optical properties. In this study, we synthesized a dicarboxylic acid ligand with amide groups and successfully synthesized a novel two-dimensional (2D) MOF with the molecular formula C42H31EuN4O10 (Eu-MOF) by a solvothermal method. Single-crystal X-ray diffraction showed that amide groups are exposed on the outside of the two-dimensional coordination layer, with the possibility of recognizing specific molecules through hydrogen bonding interactions. The ligand's "antenna effect" enables Eu-MOF to emit a strong luminescence characterized by the "f-f" transition. Further studies have revealed that Eu-MOF could be used as a bifunctional fluorescent probe for the selective detection of benzaldehyde and Fe3+. The sensing mechanism has been analyzed in detail through powder X-ray diffraction (PXRD) analysis, UV-vis spectroscopy, fluorescence lifetime measurement, and density functional (DFT) theory calculation. This design and research can provide a reference for subsequent related work.

5.
Inorg Chem ; 63(29): 13474-13483, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38976574

RESUMO

Traditional information encryption materials that rely on fluorescent/phosphorescent molecules are facing an increasing risk of counterfeiting or tampering due to their static reading mode and advances in counterfeiting technology. In this study, a series of Mg2-xZnxSnO4 (x = 0.55, 0.6, 0.65, 0.7 0.75, 0.8) that realizes the writing, reading, and erasing of dynamic information is developed. When heated to 90 °C, the materials exhibit a variety of dynamic emission changes with the concentration of Zn2+ ions. As the doping concentration increased, the ratio of the shallow trap to deep trap changed from 7.77 to 20.86. When x = 0.55, the proportion of deep traps is relatively large, resulting in a higher temperature and longer time required to read the information. When x = 0.80, the proportion of shallow traps is larger and the encrypted information is easier to read. Based on the above features, encryption binary codes device was designed, displaying dynamic writing, reading, and erasing of information under daylight and heating conditions. Accordingly, this work provides reliable guidance on advanced dynamic information encryption.

6.
Chem Sci ; 15(21): 8052-8061, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38817568

RESUMO

Room temperature phosphorescence (RTP) materials are increasingly recognized for their superior luminescent properties, which are pivotal in applications such as anti-counterfeiting, information storage, and optoelectronics. Despite this, the sensitivity of most RTP systems to humidity presents a significant challenge in achieving durable RTP performance in aqueous environments. This study proposes a strategy to enhance organic room-temperature phosphorescence through racemization. By incorporating external racemates of various chiral phosphors-NDBD-Ph, NDBD-Ph-Ph, NDBD-CH3, and NDBD-O-CH3-into a polyacrylonitrile (PAN) matrix, we significantly enhance the RTP properties (quantum yield, lifetime, and afterglow-time) of the resultant films. This enhancement can be attributed to the increased density of racemic molecules in the matrix and the increased spin-orbit coupling (SOC), facilitating the development of a long-lasting polymer RTP system in water. Notably, the racemic rac-NDBD-Ph@PAN film exhibits a persistent bright turquoise afterglow, even after immersion in water for a month. Furthermore, for the first time, we achieved an enhanced green to cyan RTP response to pH variations under both acidic and alkaline conditions (pH = 2-12), with the maximum phosphorescence emission intensity increasing up to threefold. The remarkable water stability, reversible response characteristics, and enhanced phosphorescence properties of this system offer promising potential for dynamic information encryption in aqueous environments.

7.
Inorg Chem ; 63(14): 6192-6201, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38518256

RESUMO

Fe2O3 is a promising semiconductor for photoelectrochemical (PEC) water decomposition. However, severe charge recombination problems limit its applications. In this study, a F-Fe2O3-x/MoS2 nanorod array photoanode was designed and prepared to facilitate charge separation. Detailed characterization and experimental results showed that F doping in Fe2O3 regulated the electronic structure to improve the conductivity of Fe2O3 and induced abundant oxygen vacancies to increase the carrier concentration and promote charge separation in bulk. In addition, the internal electric field between F-Fe2O3-x and MoS2 facilitated the qualitative transfer of the photogenerated charge, thus inhibiting their recombination. The synergistic effect between the oxygen vacancy and F-Fe2O3-x/MoS2 heterojunction significantly enhanced the PEC performance of Fe2O3. This study provides a universal strategy for designing other photoanode materials with high-efficiency charge separation.

8.
Hortic Res ; 11(1): uhad265, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298900

RESUMO

Peach (Prunus persica) landrace has typical regional characteristics, strong environmental adaptability, and contains many valuable genes that provide the foundation for breeding excellent varieties. Therefore, it is necessary to assemble the genomes of specific landraces to facilitate the localization and utilization of these genes. Here, we de novo assembled a high-quality genome from an ancient blood-fleshed Chinese landrace Tianjin ShuiMi (TJSM) that originated from the China North Plain. The assembled genome size was 243.5 Mb with a contig N50 of 23.7 Mb and a scaffold N50 of 28.6 Mb. Compared with the reported peach genomes, our assembled TJSM genome had the largest number of specific structural variants (SVs) and long terminal repeat-retrotransposons (LTR-RTs). Among the LTR-RTs with the potential to regulate their host genes, we identified a 6688 bp LTR-RT (named it blood TE) in the promoter of NAC transcription factor-encoding PpBL, a gene regulating peach blood-flesh formation. The blood TE was not only co-separated with the blood-flesh phenotype but also associated with fruit maturity date advancement and different intensities of blood-flesh color formation. Our findings provide new insights into the mechanism underlying the development of the blood-flesh color and determination of fruit maturity date and highlight the potential of the TJSM genome to mine more variations related to agronomic traits in peach fruit.

9.
Inorg Chem ; 63(8): 3921-3930, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335732

RESUMO

Metal-organic frameworks (MOFs) with multifunctional and tunable optical properties have unique advantages in the field of sensing, and the structure and properties of MOFs are significantly influenced by the ligands. In this study, a Y-type tricarboxylic acid ligand containing amide bonds was synthesized through functional guidance, and three isomorphic and heterogeneous three-dimensional MOFs (Eu-MOF, Tb-MOF, and Gd-MOF) were obtained by solvothermal reaction. Further studies revealed that both the Tb-MOF and Eu-MOF could selectively detect picric acid (PA). The luminescence quenching of the two MOFs by PA was attributed to competing absorption and photoelectron energy transfer mechanisms. In addition, due to the energy transfer between Tb and Rhodamine B, Rhodamine B was encapsulated into Tb-MOF. The obtained material exhibited a linear relationship between the temperature parameters I544/I584 and temperature within the range of 280-400 K, the correlation coefficient (R2) reached an impressive value of 0.999, and the absolute sensitivity of the sample used for temperature sensing was 1.534% K-1. What is more, the material exhibited a good response to trifluoroacetic acid vapor, which suggests the potential of the material for temperature sensing and detection of trifluoroacetic acid vapor. The designed and investigated strategy can also serve as a reference for further research on excellent multifunctional sensors.

10.
Inorg Chem ; 63(4): 1725-1735, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38225216

RESUMO

NaH2SIP was selected as an organic ligand (NaH2SIP = 5-sulfoisophthalic acid monosodium salt). We successfully constructed a new class of lanthanide coordination polymers Ln-HS ([Ln(SIP)(DMF)(H2O)4]DMF·H2O; Ln = Eu, Tb, Sm, and Dy) by a simple solvothermal synthesis method. They exhibited excellent photoluminescence properties for Ln3+ ions, where Eu-HS and Tb-HS exhibited high quantum yields of 13.70 and 42.38%, respectively. The codoped lanthanide coordination polymers obtained by doping with different ratios of Eu3+/Tb3+ serve as excellent ratiometric thermometers with high sensitivities in the physiological temperature range, with values of 16.8, 7.0, and 14.5%·K-1, respectively. The luminescent colors of Tb0.95Eu0.05-HS and Tb0.94Eu0.06-HS exhibit variations from green to yellow to orange, achieving visualized luminescence in a narrow temperature range. The composite film material Tb0.94Eu0.06-HS@PMMA demonstrates this color variation. Next, Tb0.5Sm0.5-HS obtained by Tb3+/Sm3+ codoping was investigated. The difference in the luminescence colors visible to the naked eye at different excitation wavelengths and the change in luminescence colors occur in a very narrow temperature range. All of them show the great value of the visualized luminescence in practical anticounterfeiting, with double anticounterfeiting function and high security.

11.
Inorg Chem ; 62(46): 19015-19024, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37919966

RESUMO

Highly efficient transformation of carbon dioxide (CO2) into value-added chemicals is considered a promising route for clean production and future energy sustainability, which is crucial for realizing a carbon-neutral economy. It remains a great challenge to develop highly stable and active catalysts with low-cost, environmentally friendly, and nontoxic materials for catalytic conversion of CO2. Herein, a precious-metal-free and heterogeneous MOF (LTG-FeZr) catalyst, composed of bis(terpyridine)iron(II) complexes and zirconium(IV) ions, was designed and prepared via a metalloligand approach. LTG-FeZr, with a robust framework and regular 1D channels not only can achieve the photocatalytic reduction of CO2 to HCOOH with a high conversion rate (up to 265 µmol·g-1·h-1) under visible-light irradiation but also exhibits exceptional catalytic activities toward the synthesis of cyclic carbonates via cycloaddition reactions of various epoxides and CO2 in the absence of light. Possible mechanisms for two different conversion processes of CO2 catalyzed by LTG-FeZr have been proposed. LTG-FeZr represents an ideal dual-function MOF platform for the catalytic conversion and utilization of CO2 in all weather conditions.

12.
Dalton Trans ; 52(47): 18082-18089, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37997171

RESUMO

One of the environmentally friendly methods is the intelligent utilization of natural one-dimensional nanomaterials as carriers to improve the CO2 catalytic performance of MOF materials. This paper reports an efficient composite catalyst preparation using a cheap and readily available magnesium-aluminosilicate nanometer, attapulgite (ATP), as a carrier for MOF materials. Due to its Lewis acidic site and unique alkaline pore structure, ATP exhibits excellent catalytic activity in the coupling reaction of CO2 with epoxy compounds, and its regular one-dimensional nanorod shape has tremendous potential as a carrier compared to other natural minerals. Given the diversity of MOF material types and structures, the design of this UIO-66/ATP nanocomposite catalyst provides both a new pathway for CO2 capture and conversion and a developmental space for the synthesis of such nanocomposites.

13.
Dalton Trans ; 52(43): 15907-15917, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37840534

RESUMO

The direct oxidative esterification of benzaldehydes and benzyl alcohols to high value-added aromatic esters under mild and green reaction conditions is significant in the fine chemical industry. The accurate design of catalysts with high catalytic performance is crucial for this process. Herein, 2,4,6-trimethylpyridine, benzoic anhydride, and terephthalaldehyde were used to prepare a covalent organic framework (COF) material, which was then used as a template to construct a mesoporous CeO2-supported Au nanoparticles catalyst. The obtained Au@CeO2 catalyst was thoroughly characterized, and it possessed a mesoporous structure with a high surface area. Meanwhile, the as-prepared Au@CeO2 exhibited excellent catalytic performance in the oxidative esterification of benzaldehydes and benzyl alcohols with methanol, affording the corresponding aromatic esters under mild and green reaction conditions. Furthermore, the Au@CeO2 catalyst could also be recycled. Therefore, this study provides a green and sustainable pathway for the synthesis of high-value-added esters through a direct oxidative esterification strategy.

14.
Dalton Trans ; 52(39): 14132-14141, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37747221

RESUMO

The optical characteristics of multimode luminescent materials like multimode luminescence (photoluminescence, afterglow, thermoluminescence) and a multi-excitation source (light, thermal, mechanical force) play crucial roles in optical data storage and readout, document security and anticounterfeiting. A higher level of advanced anticounterfeiting may rely on multimode anticounterfeiting materials that can realize multicolor luminescence. Here, a highly integrated multimode and multicolor Y7O6F9:Er3+,Eu3+ material is developed through multiplexing of dual lanthanides in fluorine oxide particles. In photoluminescence and photoluminescence/up-conversion luminescence modes, the material Y7O6F9:Er3+,Eu3+ has the characteristic of excitation wavelength and power dependence. In the photoluminescence mode, under excitation at 254 nm and 365 nm, Y7O6F9:Er3+ and Y7O6F9:Eu3+ showed bright red and green emissions, respectively. In the photoluminescence/up-conversion mode, under the increased excitation power from 0.2 to 2.0 W cm-2, the color of luminescence emission can be finely tuned from red to orange, yellow and green. Taking this unique excitation wavelength-power-dependent luminescence property into account, a multilevel anticounterfeiting device with the Lily pattern was designed. The device readily integrates the advantages of the excitation wavelength-dependent photoluminescence emissions and excitation power-dependent photoluminescence emissions in one overall device. These findings offer unique insight for designing highly integrated multimode, multicolor luminescence materials and advanced anticounterfeiting technology toward a wide variety of applications, particularly multilevel anticounterfeiting devices.

15.
Sci Rep ; 13(1): 15247, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709842

RESUMO

Members of the eukaryotic translation initiation complex are co-opted in viral infection, leading to susceptibility in many crop species, including stone fruit trees (Prunus spp.). Therefore, modification of one of those eukaryotic translation initiation factors or changes in their gene expression may result in resistance. We searched the crop and wild Prunus germplasm from the Armeniaca and Amygdalus taxonomic sections for allelic variants in the eIF4E and eIFiso4E genes, to identify alleles potentially linked to resistance to Plum pox virus (PPV). Over one thousand stone fruit accessions (1397) were screened for variation in eIF4E and eIFiso4E transcript sequences which are in single copy within the diploid Prunus genome. We identified new alleles for both genes differing from haplotypes associated with PPV susceptible accessions. Overall, analyses showed that eIFiso4E is genetically more constrained since it displayed less polymorphism than eIF4E. We also demonstrated more variations at both loci in the related wild species than in crop species. As the eIFiso4E translation initiation factor was identified as indispensable for PPV infection, a selection of ten different eIFiso4E haplotypes along 13 accessions were tested by infection with PPV and eight of them displayed a range of reduced susceptibility to resistance, indicating new potential sources of resistance to sharka.


Assuntos
Fator de Iniciação 4E em Eucariotos , Prunus , Alelos , Fator de Iniciação 4E em Eucariotos/genética , Fatores de Iniciação em Eucariotos/genética , Citoplasma , Prunus/genética
16.
Dalton Trans ; 52(33): 11649-11657, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37552091

RESUMO

In recent years, a series of persistent luminescence materials excitable by blue light have been developed and widely used in many fields such as optical information storage, AC-LEDs, anti-counterfeiting and bio-imaging. However, it is still a long-standing challenge to develop a superior red-emitting persistent phosphor that can be efficiently excited by blue light. In this work, a novel blue-light excited red-emitting persistent phosphor CaCd2Ga2Ge3O12:Pr3+ was successfully synthesized by using a solid-state method, showing excellent luminescence properties. Moreover, the phase purity, crystal structure, photoluminescence spectra, afterglow emission spectra, and three-dimensional thermoluminescence spectrum were successfully investigated. Under 294 nm excitation, photoluminescence spectra show a single orange emission and a series of peaks centered at 492, 537, 568, 614 and 664 nm, which correspond to the 3P0 → 3H4, 3P0 → 3H5, 3P2 → 3H6, 1D2 → 3H4, and 3P0 → 3F2 transitions of Pr3+, respectively. Interestingly, after blue light excitation, the afterglow luminescence exhibits red long emission, which is attributed to the 1D2 → 3H4 transition of Pr3+. Through thermoluminescence spectra and three-dimensional thermoluminescence spectra, we analyze the reasons for the different colors of photoluminescence and afterglow luminescence. The results imply that there are two types of traps, and the depth of shallow traps and deep traps is calculated to be 0.684 and 0.776 eV, respectively. It is worth noting that the photoluminescence is attributed to the 4f2 → 4f5d and f → f transitions of Pr3+, and the afterglow luminescence is ascribed to a tunneling-related process and the transition of electrons from the valence band to the conduction band. The obtained red-emitting persistent phosphors provide a promising pathway toward AC-LEDs, multi-cycle bio-imaging and other fields.

17.
Front Plant Sci ; 14: 1196754, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324711

RESUMO

Kernel-using apricot (Prunus armeniaca L.) is an economically important fruit tree species in arid areas owing to its hardiness and cold and drought tolerance. However, little is known about its genetic background and trait inheritances. In the present study, we first evaluated the population structure of 339 apricot accessions and the genetic diversity of kernel-using apricots using whole genome re-sequencing. Second, the phenotypic data of 222 accessions were investigated for two consecutive seasons (2019 and 2020) for 19 traits, including kernel and stone shell traits and the pistil abortion rate of flowers. Heritability and correlation coefficient of traits were also estimated. The stone shell length (94.46%) showed the highest heritability, followed by the length/width ratio (92.01%) and length/thickness ratio (92.00%) of the stone shell, whereas breaking force of the nut (17.08%) exhibited a very low heritability. A genome-wide association study (GWAS) using general linear model and generalized linear mixed model revealed 122 quantitative trait loci (QTLs). The QTLs of the kernel and stone shell traits were unevenly assigned on the eight chromosomes. Out of the 1,614 candidate genes identified in the 13 consistently reliable QTLs found using the two GWAS methods and/or in the two seasons, 1,021 were annotated. The sweet kernel trait was assigned to chromosome 5 of the genome, similar to the almond, and a new locus was also mapped at 17.34-17.51 Mb on chromosome 3, including 20 candidate genes. The loci and genes identified here will be of significant use in molecular breeding efforts, and the candidate genes could play essential roles in exploring the mechanisms of genetic regulation.

18.
ACS Appl Mater Interfaces ; 15(25): 30320-30331, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37312235

RESUMO

[Ru(Phen)3]2+ (phen = phenanthroline) as a very classical photosensitizer possesses strong absorption in the visible range and facilitates photoinduced electron transfer, which plays a vital role in regulating photochemical reactions. However, it remains a significant challenge to utilize more adequately and exploit more efficiently the ruthenium-based materials due to the uniqueness, scarcity, and nonrenewal of the noble metal. Here, we integrate the intrinsic advantages of the ruthenium-based photosensitizer and mesoporous metal-organic frameworks (meso-MOFs) into a [Ru(Phen)3]2+ photosensitizer-embedded heterometallic Ni(II)/Ru(II) meso-MOF (LTG-NiRu) via the metalloligand approach. LTG-NiRu, with an extremely robust framework and a large one-dimensional (1D) channel, not only makes ruthenium photosensitizer units anchored in the inner wall of meso-MOF tubes to circumvent the problem of product/catalyst separation and recycling of catalysts in heterogeneous systems but also exhibits exceptional activities for the aerobic photocatalytic oxidative coupling of amine derivatives as a general photocatalyst. The conversion of the light-induced oxidative coupling reaction for various benzylamines is ∼100% in 1 h, and more than 20 chemical products generated by photocatalytic oxidative cycloaddition of N-substituted maleimides and N,N-dimethylaniline can be synthesized easily in the presence of LTG-NiRu upon visible light irradiation. Moreover, recycling experiments demonstrate that LTG-NiRu is an excellent heterogeneous photocatalyst with high stability and excellent reusability. LTG-NiRu represents a great potential photosensitizer-based meso-MOF platform with an efficient aerobic photocatalytic oxidation function that is convenient for gram-scale synthesis.

19.
Inorg Chem ; 62(25): 9781-9791, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37307418

RESUMO

Lanthanide luminescent MOF materials show excellent luminescent properties. However, obtaining lanthanide luminescent MOFs with high quantum yield is a challenging research. A novel bismuth-based metal-organic framework [Bi(SIP)(DMF)2] was constructed by solvothermal method, utilizing 5-sulfoisophthalic acid monosodium salt (NaH2SIP) and Bi(NO3)3·5H2O. Thereafter, doped MOFs (Ln-Bi-SIP, Ln = Eu, Tb, Sm, Dy, Yb, Nd, Er) with different luminescent properties have been obtained by in situ doping with different lanthanide metal ions, among which Eu-Bi-SIP, Tb-Bi-SIP, Sm-Bi-SIP, and Dy-Bi-SIP have high quantum yield. What is special is that the doping amount of Ln3+ ions is very low, and the doped MOF can achieve high luminescence quantum yields. EuTb-Bi-SIP obtained by Eu3+/Tb3+ codoping and Dy-Bi-SIP exhibit good temperature sensing performance over a wide temperature range with the maximum sensitivity Sr of 1.6%·K-1 (433 K) and 2.6%·K-1, respectively (133 K), while the cycling experiments also show good repeatability in the assay temperature range. Finally, considering the practical application value, EuTb-Bi-SIP was blended with an organic polymer poly(methyl methacrylate) (PMMA) to produce a thin film, which shows different color changes at different temperatures.

20.
Sci Rep ; 13(1): 8907, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264078

RESUMO

To describe the spatiotemporal variations characteristics and future trends of urban air quality in China, this study evaluates the spatiotemporal evolution features and linkages between the air quality index (AQI) and six primary pollution indicators, using air quality monitoring data from 2014 to 2022. Seasonal autoregressive integrated moving average (SARIMA) and random forest (RF) models are created to forecast air quality. (1) The study's findings indicate that pollution levels and air quality index values in Chinese cities decline annually, following a "U"-shaped pattern with a monthly variation. The pollutant levels are high in winter and low in spring, and low in summer and rising in the fall (O3 shows the opposite). (2) The spatial distribution of air quality in Chinese cities is low in the southeast and high in the northwest, and low in the coastal areas and higher in the inland areas. The correlation coefficients between AQI and the pollutant concentrations are as follows: fine particulate matter (PM2.5), inhalable particulate matter (PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) values are correlated at 0.89, 0.84, 0.54, 0.54, 0.32, and 0.056, respectively. (3) In terms of short-term AQI predictions, the RF model performs better than the SARIMA model. The long-term forecast indicates that the average AQI value in Chinese cities is expected to decrease by 0.32 points in 2032 compared to the 2022 level of 52.95. This study has some guiding significance for the analysis and prediction of urban air quality.

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