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1.
Inorg Chem ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39178151

RESUMO

This article describes a new kind of afterglow material, ScBaZn3GaO7:Bi3+, which was synthesized through a high-temperature solid-phase method. Its crystal structure, photoluminescent characteristics, and afterglow characteristics were studied and analyzed. Upon excitation at 344 nm, ScBaZn3GaO7:Bi3+ exhibits broadband emission with a central wavelength located at 571 nm (fwhm = 172.98 nm). The sample exhibits an internal quantum efficiency of 65.1%. The bright yellow persistent luminescence of the ScBaZn3GaO7:Bi3+ sample was observed after 365 nm irradiation. Thermoluminescence spectroscopy revealed four primary traps within ScBaZn3GaO7:Bi3+, with depths of 0.676, 0.794, 0.882, and 0.972 eV. The traps located at energy levels of 0.676 and 0.794 eV were identified as the key contributors to the sample's afterglow. Finally, the ScBaZn3GaO7:Bi3+ sample was combined with a UV-LED chip to fabricate a high-power warm white-light-emitting diode (WLED) device, indicating the potential application prospect of ScBaZn3GaO7:Bi3+ phosphor in single-phase warm WLEDs.

2.
Opt Lett ; 48(4): 872-875, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36790963

RESUMO

Recycling Pb from lead acid batteries is rather important in environmental protection, but current strategies need a high temperature or produce secondary pollution. Herein, we present a green reactant recycling method to synthesize PbI2 micro-crystals by extracting the Pb from waste lead acid batteries. Systematical characterizations indicate that the as-prepared PbI2 micro-crystals show high purity, high crystal quality with a 2H-hexagonal crystal structure, and excellent optical properties with a bandgap of 2.3 eV. Based on the recycled 2H-PbI2 micro-crystals, a symmetrically structured ITO/PbI2/ITO photodetector is fabricated. Under 10 V bias voltage, the device reveals a distinct photo-response to UV-visible light and superior performance, with a dark current of 1.06 nA, an on-off ratio of 103, a responsivity of 15.5 mA/W, and a detectivity of 4.7 × 1010 Hz1/2 W-1. In addition, the photodetector also exhibits relatively rapid response speeds of 69 ms (rise time) and 64 ms (decay time). Our study provides an innovative and green strategy for producing a UV-visible photodetector based on recycled lead acid batteries, which is significant in environmental protection and the recycling economy.

3.
Int J Mol Sci ; 23(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35457178

RESUMO

Being an invasive plant, Polygonum cuspidatum is highly resilient and can survive in unfavorable environments for long periods; however, its molecular mechanisms associated with such environmental resistance are largely unknown. In this study, a WRKY transcription factor (TF) gene, PcWRKY11, was identified from P. cuspidatum by analyzing methyl jasmonate (MeJA)-treated transcriptome data. It showed a high degree of homology with WRKY11 from Arabidopsis thaliana, containing a WRKY domain and a zinc finger structure and II-d WRKY characteristic domains of HARF, a calmodulin-binding domain (C-motif), and a putative nuclear localization signal (NLS) through sequence alignment and functional element mining. qPCR analysis showed that the expression of PcWRKY11 can be induced by NaCl, osmotic stress, and UV-C. In this study, we also found that overexpression of PcWRKY11 in A. thaliana could significantly increase salt tolerance. To explore its possible molecular mechanism, further investigations showed that compared with the wild type (WT), under salt stress, the transgenic plants showed a lower malondialdehyde (MDA) content, higher expression of ascorbate peroxidase (APX) and superoxide dismutase (SOD), and higher enzyme activity of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT). Moreover, the transgenic plants also showed higher expression of Δ1-pyrroline-5-carboxylate synthase (AtP5CS), and higher contents of proline and soluble sugar. Taken together, these results indicate that PcWRKY11 may have a positive role in plants' adaptation to salinity conditions by reducing reactive oxygen species (ROS) levels and increasing osmosis substance synthesis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fallopia japonica , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fallopia japonica/genética , Fallopia japonica/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Opt Lett ; 46(4): 737-740, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33577502

RESUMO

The surface plasmon resonance (SPR) of metal nanostructures is known to affect the optical properties of solid luminescent materials. Ag nanoparticles were first used to obtain a wider color gamut in rare-earth-doped phosphor-in-glass for application as color filters for white light emitting diodes. The existence of Ag nanocrystallites at nanometer scale and the independent integrity of the phosphor luminescence center in the amorphous glass environment were demonstrated. Using UV-Vis spectroscopy, the localized SPR absorption band was observed at 480 nm, and the optical properties of the nanostructures were found to be dependent on the annealing temperature. Hence, an expansion of the color gamut from 79.07% to 93.31% was realized by the coefficient effect of Nd3+ active ions and Ag nanoparticles. These results suggest that Nd3+-ion-co-doped phosphor-in-glass modified by Ag nanoparticles could be potentially applied as a novel optical material with a wide color gamut.

5.
Int J Mol Sci ; 21(11)2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32512879

RESUMO

Nitrogen (N) is an essential macronutrient for plant growth. Plants absorb and utilize N mainly in the form of nitrate (NO3-) or ammonium (NH4+). In this study, the nitrate transporter DsNRT3.1 (also known as the nitrate assimilation-related protein DsNAR2.1) was characterized from Dianthus spiculifolius. A quantitative PCR (qPCR) analysis showed that the DsNRT3.1 expression was induced by NO3-. Under N-starvation conditions, the transformed Arabidopsis seedlings expressing DsNRT3.1 had longer roots and a greater fresh weight than the wild type. Subcellular localization showed that DsNRT3.1 was mainly localized to the plasma membrane in Arabidopsis root hair cells. Non-invasive micro-test (NMT) monitoring showed that the root hairs of N-starved transformed Arabidopsis seedlings had a stronger NO3- and NH4+ influx than the wild-type seedlings, using with NO3- or NH4+ as the sole N source; contrastingly, transformed seedlings only had a stronger NO3- influx when NO3- and NH4+ were present simultaneously. In addition, the qPCR analysis showed that the expression of AtNRT2 genes (AtNRT2.1-2.6), and particularly of AtNRT2.5, in the transformed Arabidopsis differed from that in the wild type. Overall, our results suggest that the heterologous expression of DsNRT3.1 affects seedlings' growth by enhancing the NO3- and NH4+ uptake in N-starved Arabidopsis. This may be related to the differential expression of AtNRT2 genes.


Assuntos
Compostos de Amônio/metabolismo , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Nitratos/metabolismo , Sequência de Aminoácidos , Proteínas de Transporte de Ânions/química , Arabidopsis/classificação , Proteínas de Arabidopsis/química , Transporte Biológico , Expressão Gênica , Transportadores de Nitrato , Filogenia , Plântula/genética , Plântula/metabolismo
6.
Plant Cell Rep ; 37(3): 443-452, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29307003

RESUMO

KEY MESSAGE: Suppression of AtVHA-c5 expression results in changes in H+ and Na+ fluxes of roots, and increase sensitivity to salt in Arabidopsis. Vacuolar-type H+-ATPase (V-ATPase), a multisubunit endomembrane proton pump, is essential in plant growth and response to environmental stresses. In the present study, the function of Arabidopsis V-ATPase subunit c5 (AtVHA-c5) gene in response to salt stress was investigated. Subcellular localization showed that AtVHA-c5 was mainly localized to endosomes and the vacuolar membrane in Arabidopsis. The analysis of quantitative real-time PCR showed that expression of AtVHA-c5 gene was induced by NaCl stress. Histochemical analysis revealed that AtVHA-c5 was expressed in the root epidermis of untreated Arabidopsis and in the whole root elongation zone after NaCl treatment. Phenotypic analysis showed that the atvha-c5 mutant is sensitive to high NaCl as compared to the wild type. The non-invasive micro-test technology measurement demonstrated that the net H+ and Na+ efflux in the root elongation zone of the atvha-c5 mutant was weaker than that of the wild type under NaCl treatment, suggesting that H+ and Na+ fluxes in atvha-c5 roots are impaired under NaCl stress. Moreover, compared to the wild type, the expression of AtSOS1 (salt overly sensitive 1) and AtAHA1 (plasma membrane H+-ATPase 1) were down-regulated in atvha-c5 roots under NaCl stress. Overall, our results indicate that AtVHA-c5 plays a role in Arabidopsis root response to NaCl stress by influencing H+ and Na+ fluxes.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Cloreto de Sódio/farmacologia , ATPases Vacuolares Próton-Translocadoras/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Hidrogênio/metabolismo , Mutação , Epiderme Vegetal/genética , Epiderme Vegetal/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Tolerância ao Sal/genética , Sódio/metabolismo , Estresse Fisiológico , ATPases Vacuolares Próton-Translocadoras/metabolismo , Vacúolos/genética , Vacúolos/metabolismo
7.
Int J Mol Sci ; 19(6)2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29794972

RESUMO

Plant SWEETs (Sugars Will Eventually be Exported Transporters) affect the growth of plants by regulating the transport of sugar from source to sink and its intracellular transport between different organelles. In this study, DsSWEET17 from Dianthus spiculifolius was identified and characterized. Real-time quantitative PCR analysis revealed that the expression of DsSWEET17 was affected by exogenous application of fructose and glucose as well as under salt, osmotic, and oxidation stress. Colocalization experiments showed that the DsSWEET17-GFP (green fluorescent protein) fusion protein was localized to the FM4-64-labeled tonoplasts in Arabidopsis. Compared to the wild type, the transgenic Arabidopsis seedlings overexpressing DsSWEET17 had longer roots, greater fresh weight, and a faster root growth upon exogenous application of fructose. Furthermore, transgenic Arabidopsis seedlings had significantly higher fructose accumulation than was observed for the wild-type seedlings. The analysis of root length revealed that transgenic Arabidopsis had higher tolerance to salt, osmotic, and oxidative stresses. Taken together, our results suggest that DsSWEET17 may be a tonoplast sugar transporter, and its overexpression affects sugar metabolism and confers multiple stress tolerance in Arabidopsis.


Assuntos
Arabidopsis/genética , Dianthus/genética , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Vacúolos/metabolismo
8.
Int J Mol Sci ; 19(2)2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29414886

RESUMO

Plant SWEETs (sugars will eventually be exported transporters) play a role in plant growth and plant response to biotic and abiotic stresses. In the present study, DsSWEET12 from Dianthus spiculifolius was identified and characterized. Real-time quantitative PCR analysis revealed that DsSWEET12 expression was induced by sucrose starvation, mannitol, and hydrogen peroxide. Colocalization experiment showed that the DsSWEET12-GFP fusion protein was localized to the plasma membrane, which was labeled with FM4-64 dye, in Arabidopsis and suspension cells of D. spiculifolius. Compared to wild type plants, transgenic Arabidopsis seedlings overexpressing DsSWEET12 have longer roots and have a greater fresh weight, which depends on sucrose content. Furthermore, a relative root length analysis showed that transgenic Arabidopsis showed higher tolerance to osmotic and oxidative stresses. Finally, a sugar content analysis showed that the sucrose content in transgenic Arabidopsis was less than that in the wild type, while fructose and glucose contents were higher than those in the wild type. Taken together, our results suggest that DsSWEET12 plays an important role in seedling growth and plant response to osmotic and oxidative stress in Arabidopsis by influencing sugar metabolism.


Assuntos
Metabolismo dos Carboidratos , Dianthus/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Pressão Osmótica , Estresse Oxidativo , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Transporte Biológico , Dianthus/genética , Frutose/metabolismo , Glucose/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Plântula/genética , Plântula/metabolismo , Sacarose/metabolismo , Transcriptoma/genética
9.
Opt Lett ; 42(3): 478-481, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28146506

RESUMO

Two types of engineered nodules in Ta2O5/SiO2 high-reflection coatings were prepared using electron beam evaporation and an ion-assisted deposition processes to facilitate poor and good boundary continuity, respectively. The influence of nodular boundary continuity on their nanosecond laser damage characteristics was investigated through experimental studies, combined with 3D finite-difference time domain simulations and photo-thermal micro-characterizations. Better boundary continuity led to improved mechanical stability and higher ejection fluence of nodules, in accordance with the thermomechanical damage model. In contrast, the ejected nodules that initially had better boundary continuity exhibited higher localized absorption and lower damage growth fluence, which is attributed to the creation of mechanically induced electronic defects or stronger electric field intensity enhancement at the ejected nodules.

10.
Appl Opt ; 56(4): C188-C192, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28158072

RESUMO

The influence of coating thickness on laser-induced damage (LID) characteristics of anti-reflection (AR) coatings irradiated by 1064 nm nanosecond laser pulses was investigated. Two HfO2/SiO2 AR coatings with different physical thicknesses, 0.7 and 2.7 µm, were prepared and tested. To study the effect of coating thickness on a laser-induced damage threshold (LIDT) in isolation, electric field intensities (EFIs) at the substrate-coating interface were kept the same by using proper AR designs. Moreover, 2 nm artificial gold particles with a density of 10 mm-2 were implanted into the substrate-coating interface to achieve reliable experimental results. An optical microscope (OM) and a scanning electron microscope (SEM) were used for an online LIDT test and offline LID morphology observation, respectively. The typical LID morphology of thicker AR coatings was flat bottom craters with diameters of 20-50 µm, which can be easily observed by an online OM. For thinner AR coatings, hemispherical craters with diameters down to 1 µm were found as typical LID morphology by a SEM. However, these tiny craters could not be observed by an online OM. Moreover, such tiny craters did not grow with subsequent pulses, so they did not degrade the functional laser damage resistance of the thin AR coatings. When identified with an online OM, the LIDT of thinner AR coatings is found to be about two times higher than the thicker ones, and large delamination was mainly found as the LID morphology of AR coatings with high fluence. When observed with a SEM, the LIDT of thin AR coatings with tiny craters was over 60% lower than the LIDT of thick AR coatings, which agrees with the model that less energy is required to form smaller LID craters of thinner coatings.

11.
Int J Mol Sci ; 18(4)2017 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-28420173

RESUMO

Dianthus spiculifolius, a perennial herbaceous flower and a member of the Caryophyllaceae family, has strong resistance to cold and drought stresses. To explore the transcriptional responses of D. spiculifolius to individual and combined stresses, we performed transcriptome sequencing of seedlings under normal conditions or subjected to cold treatment (CT), simulated drought treatment (DT), or their combination (CTDT). After de novo assembly of the obtained reads, 112,015 unigenes were generated. Analysis of differentially expressed genes (DEGs) showed that 2026, 940, and 2346 genes were up-regulated and 1468, 707, and 1759 were down-regulated in CT, DT, and CTDT samples, respectively. Among all the DEGs, 182 up-regulated and 116 down-regulated genes were identified in all the treatment groups. Analysis of metabolic pathways and regulatory networks associated with the DEGs revealed overlaps and cross-talk between cold and drought stress response pathways. The expression profiles of the selected DEGs in CT, DT, and CTDT samples were characterized and confirmed by quantitative RT-PCR. These DEGs and metabolic pathways may play important roles in the response of D. spiculifolius to the combined stress. Functional characterization of these genes and pathways will provide new targets for enhancement of plant stress tolerance through genetic manipulation.


Assuntos
Temperatura Baixa , Dianthus/fisiologia , Secas , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Transcriptoma , Análise por Conglomerados , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Fenótipo , Mapeamento de Interação de Proteínas
12.
Appl Opt ; 53(4): A96-102, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24514256

RESUMO

The influence of the incidence angle and polarization state on the damage site characteristics of fused silica under 355 nm laser irradiation was investigated. The initial damage morphologies and growth behaviors of the damage sites on the exit surface at incidence angles of 0° and 45° as well as in P and S states were compared to investigate the effects of various angles and polarization states. The relationships between the size of the initial damage sites and the laser fluence, as well as the growth threshold, were discussed. The damage morphologies of the craters and cracks at different incidence angles and polarization states were then investigated. Finally, the growth characteristics of the lateral size, crater depth, and crack depth were compared and analyzed.

13.
Int J Biol Macromol ; 270(Pt 2): 132450, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772462

RESUMO

A comparative transcriptomic and metabolomic analysis of Polygonum cuspidatum leaves treated with MeJA was carried out to investigate the regulatory mechanisms of its active compounds. A total of 692 metabolites and 77,198 unigenes were obtained, including 200 differentially accumulated metabolites and 6819 differentially expressed genes. We screened potential regulatory transcription factors involved in resveratrol and flavonoids biosynthesis, and successfully identified an MYB transcription factor, PcMYB62, which could significantly decrease the resveratrol content in P. cuspidatum leaves when over-expressed. PcMYB62 could directly bind to the MBS motifs in the promoter region of stilbene synthase (PcSTS) gene and repress its expression. Besides, PcMYB62 could also repress PcSTS expression and resveratrol biosynthesis in transgenic Arabidopsis thaliana. Our results provide abundant candidate genes for further investigation, and the new finding of the inhibitory role of PcMYB62 on the resveratrol biosynthesis could also potentially be used in metabolic engineering of resveratrol in P. cuspidatum.


Assuntos
Acetatos , Ciclopentanos , Fallopia japonica , Regulação da Expressão Gênica de Plantas , Metaboloma , Oxilipinas , Proteínas de Plantas , Resveratrol , Fatores de Transcrição , Transcriptoma , Resveratrol/metabolismo , Resveratrol/farmacologia , Fallopia japonica/metabolismo , Fallopia japonica/genética , Acetatos/farmacologia , Acetatos/metabolismo , Metaboloma/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Oxilipinas/farmacologia , Oxilipinas/metabolismo , Transcriptoma/efeitos dos fármacos , Ciclopentanos/farmacologia , Ciclopentanos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Aciltransferases/genética , Aciltransferases/metabolismo , Perfilação da Expressão Gênica , Plantas Geneticamente Modificadas/genética , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/efeitos dos fármacos
14.
RSC Adv ; 14(7): 4543-4555, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38312726

RESUMO

Due to their high wavelength selectivity and strong anti-interference capability, solar-blind UV photodetectors hold broad and important application prospects in fields like flame detection, missile warnings, and secure communication. Research on solar-blind UV detectors for amorphous Ga2O3 is still in its early stages. The presence of intrinsic defects related to oxygen vacancies significantly affects the photodetection performance of amorphous Ga2O3 materials. This paper focuses on growing high quality amorphous Ga2O3 films on silicon substrates through atomic layer deposition. The study investigates the impact of annealing atmospheres on Ga2O3 films and designs a blind UV detector for Ga2O3. Characterization techniques including atomic force microscopy (AFM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) are used for Ga2O3 film analysis. Ga2O3 films exhibit a clear transition from amorphous to polycrystalline after annealing, accompanied by a decrease in oxygen vacancy concentration from 21.26% to 6.54%. As a result, the response time of the annealed detector reduces from 9.32 s to 0.47 s at an external bias of 10 V. This work demonstrates that an appropriate annealing process can yield high-quality Ga2O3 films, and holds potential for advancing high-performance solar blind photodetector (SBPD) development.

15.
Materials (Basel) ; 16(3)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36770153

RESUMO

Inorganic scintillators are of great significance in the fields of medical CT, high-energy physics and industrial nondestructive testing. In this work, we confirm that the Pb4Lu3F17: Re (Re = Tb, Eu, Sm, Dy, Ho) crystals are promising candidates for a new kind of scintillator. Detailed crystal structure information is obtained by the Rietveld refinement analysis. Upon X-ray irradiation, all these scintillators exhibited characteristic 4f-4f transitions. The Ce and Gd ions were verified to be useful for enhancing the scintillation intensity via introducing energy transfer processes. The integrated scintillation intensity of the Pb4Lu3F17: Tb/Ce is about 16.8% of the commercial CsI (Tl) single crystal. Our results manifested that Pb4Lu3F17: Re has potential application in X-ray detection and imaging.

16.
Nanoscale ; 15(9): 4361-4366, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36752142

RESUMO

Excitation-dependent dynamic multicolor luminescent materials show potential for promising applications in the field of anti-counterfeiting. However, for most ultraviolet (UV)-excited lanthanide-doped materials, more than two types of activators are incorporated to realize multicolors. In this study, for the first time, KLu3F10:Tb crystals were used to realize excitation-dependent multicolor emissions. The morphology was modified by tuning the surface-coated citric acid (CA) content. During hydrothermal reactions, fluorine vacancy defects are formed on the crystal surface, and carboxyl groups (-COOH) are coated on the crystal surface to maintain the charge balance. Under 254 nm UV excitation, typical Tb3+ green emissions were observed, while a strong broadband emission peaking at 442 nm appeared in addition to these Tb3+ emissions under 365 nm excitation. The energy transfer (ET) process between the defect state and Tb3+ is clarified. This work may promote the development of single-type activator-doped multicolor luminescent materials for high-level anti-counterfeiting.

17.
Front Genet ; 14: 1289811, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075688

RESUMO

Reynoutria japonica Houtt. is an important medical plant with a long history of thousands of years in China, however, its mitochondrial genome (mitogenome) has not been reported yet. In this work, we reported and analyzed the R. japonica mitogenome. The main results include: The R. japonica mitogenome was 302,229 bp in length and encoded 48 genes, including 27 protein-coding genes (PCGs), 3 rRNA genes, and 18 tRNA genes. Repeat sequence analysis revealed that there were 54 repeat sequences ranging from 193 bp to 1,983 bp in the R. japonica mitogenome. Relative synonymous codon usage (RSCU) analysis showed that leucine (900, 11.01%) and serine (732, 8.96%) were the two most abundant amino acids, and the codons with RSCU values showed the preference of A or T ending when greater than 1. The RNA editing sites of PCGs in the R. japonica mitogenome were characterized, and 299 RNA editing sites were found. Extensive sequences transfer between mitochondrion and chloroplast were found in R. japonica, where 11 complete plastid-derived tRNA genes stayed intact in the R. japonica mitogenome. Three genes (ccmFC, cox1, and nad1) were seen to play essential roles in the evolution through selection pressure analysis. The phylogenetic analysis showed that Fallopia multiflora was the closest species with R. japonica, in consistency with the results of chloroplast genome. Overall, the current work presents the first mitogenome of R. japonica and could contribute to the phylogenetic analysis of the family Polygonaceae.

18.
Materials (Basel) ; 15(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36499845

RESUMO

The hot stamping technology of aluminum alloy is of great significance for realizing the light weight of the automobile body, and the proper process parameters are important conditions to obtain excellent aluminum alloy parts. In this paper, the thermal deformation behavior of 6016 aluminum alloy at a high temperature is experimentally studied to provide a theoretical basis for a finite element model. With the help of blank stamping finite element software, a numerical model of a 6016 aluminum alloy automobile windshield beam during hot stamping was established. The finite element model was verified by a forming experiment. Then, the effect of the process parameters, including blank holder force, die gap, forming temperature, friction coefficient, and stamping speed on aluminum alloy formability were investigated using Taguchi design, grey relational analysis (GRA), and analysis of variance (ANOVA). Stamping tests were arranged at temperatures between 480 and 570 °C, blank holder force between 20 and 50 kN, stamping speed between 50 and 200 mm/s, die gap between 1.05 t and 1.20 t (t is the thickness of the sheet), and friction coefficient between 0.15 and 0.60. It was found that the significant factors affecting the forming quality of the hot-stamped parts were blank holder force and stamping speed, with influence significance of 28.64% and 34.09%, respectively. The optimal parameters for hot stamping of the automobile windshield beam by the above analysis are that the die gap is 1.05 t, the blank temperature is 540 °C, the coefficient of friction is 0.15, stamping speed is 200 mm/s, and blank holder force is 50 kN. The optimized maximum thickening rate is 4.87% and the maximum thinning rate is 9.00%. The optimization method used in this paper and the results of the process parameter optimization provide reference values for the optimization of hot stamping forming.

19.
Dalton Trans ; 51(31): 11703-11712, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35852240

RESUMO

A series of Rb1-yKyNa3(Li3SiO4)4:Eu2+(0 ≤ y ≤ 1) phosphors were successfully synthesized through a high-temperature solid-state reaction. The introduction of K+ into the RbNa3(Li3SiO4)4:Eu2+ phosphor to partially or completely replace Rb+ allows the emission spectrum to be modulated from blue (λ = 473 nm, FWHM = 22.5 nm) to a narrow cyan band (λ = 485 nm, FWHM = 21.1 nm). As the K+ ion content increases, the space group of the phosphor evolves from I4/M to I41/A. The complete replacement of Rb+ by K+ results in the KNa3(Li3SiO4)4:Eu2+ cyan phosphor, which shows excellent thermal stability (the comprehensive emission loss is only 8% at 150 °C) and can be used to fill the cyan light gap in white LED devices. By adding the KNa3(Li3SiO4)4:Eu2+ cyan phosphor in packaging with yellow and red phosphors, the color rendering index is increased from 90.2 to 97.1 and the correlated color temperature improved to 3658 K. These results indicate that the cyan phosphor has important application value in full-spectrum white LEDs.

20.
Genes (Basel) ; 13(11)2022 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-36360217

RESUMO

Reynoutria japonica Houtt., a traditional medicine herb of the Polygonaceae family, has been used since ancient times in China due to its various pharmacological effects. Chloroplast genomes are conservative and play an essential role in population diversity analysis. However, there are few studies on the chloroplast genome of R. japonica. In this study, the complete chloroplast genomes of three R. japonica from different regions were performed by next-generation sequencing technology. The results revealed that the lengths of the three chloroplast genomes are between 163,371~163,372 bp, and they have a highly conserved structure with a pair of inverted repeat (IR) regions (31,121 bp), a large single-copy (LSC) region (87,571~87,572 bp), and a small single-copy (SSC) region (13,558 bp). In total, 132 genes were annotated, including 8 rRNA genes, 37 tRNA genes, and 87 protein-coding genes. The phylogenetic analysis strongly revealed that 13 populations of R. japonica form a monophyly, and Fallopia multiflora (Polygonaceae) is its closest species. The two species diverged at ~20.47 million years ago, and R. japonica in China could be further divided into two major groups based on genetic structure analysis. In addition, several potential loci with suitable polymorphism were identified as molecular markers. Our study provides important genetic resources for further development and utilization of R. japonica germplasm, as well as some new insights into the evolutionary characteristics of this medicinal plant.


Assuntos
Genoma de Cloroplastos , Filogenia , Reynoutria , RNA de Transferência/genética , Sequenciamento de Nucleotídeos em Larga Escala
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