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1.
Plant Cell ; 36(6): 2176-2200, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38345432

RESUMO

Phosphorus is indispensable in agricultural production. An increasing food supply requires more efficient use of phosphate due to limited phosphate resources. However, how crops regulate phosphate efficiency remains largely unknown. Here, we identified a major quantitative trait locus, qPE19, that controls 7 low-phosphate (LP)-related traits in soybean (Glycine max) through linkage mapping and genome-wide association studies. We identified the gene responsible for qPE19 as GLYCEROPHOSPHORYL DIESTER PHOSPHODIESTERASE2 (GmGDPD2), and haplotype 5 represents the optimal allele favoring LP tolerance. Overexpression of GmGDPD2 significantly affects hormone signaling and improves root architecture, phosphate efficiency and yield-related traits; conversely, CRISPR/Cas9-edited plants show decreases in these traits. GmMyb73 negatively regulates GmGDPD2 by directly binding to its promoter; thus, GmMyb73 negatively regulates LP tolerance. GmGDPD2 physically interacts with GA 2-oxidase 1 (GmGA2ox1) in the plasma membrane, and overexpressing GmGA2ox1 enhances LP-associated traits, similar to GmGDPD2 overexpression. Analysis of double mutants for GmGDPD2 and GmGA2ox1 demonstrated that GmGDPD2 regulates LP tolerance likely by influencing auxin and gibberellin dose-associated cell division in the root. These results reveal a regulatory module that plays a major role in regulating LP tolerance in soybeans and is expected to be utilized to develop phosphate-efficient varieties to enhance soybean production, particularly in phosphate-deficient soils.


Assuntos
Regulação da Expressão Gênica de Plantas , Glycine max , Fosfatos , Proteínas de Plantas , Glycine max/genética , Glycine max/metabolismo , Fosfatos/metabolismo , Fosfatos/deficiência , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Locos de Características Quantitativas/genética , Plantas Geneticamente Modificadas , Estudo de Associação Genômica Ampla
2.
Plant Physiol ; 192(2): 1099-1114, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36932694

RESUMO

Soybean (Glycine max) is a major grain and oil crop worldwide, but low phosphorus (LP) in soil severely limits the development of soybean production. Dissecting the regulatory mechanism of the phosphorus (P) response is crucial for improving the P use efficiency of soybean. Here, we identified a transcription factor, GmERF1 (ethylene response factor 1), that is mainly expressed in soybean root and localized in the nucleus. Its expression is induced by LP stress and differs substantially in extreme genotypes. The genomic sequences of 559 soybean accessions suggested that the allelic variation of GmERF1 has undergone artificial selection, and its haplotype is significantly related to LP tolerance. GmERF1 knockout or RNA interference resulted in significant increases in root and P uptake efficiency traits, while the overexpression of GmERF1 produced an LP-sensitive phenotype and affected the expression of 6 LP stress-related genes. In addition, GmERF1 directly interacted with GmWRKY6 to inhibit transcription of GmPT5 (phosphate transporter 5), GmPT7, and GmPT8, which affects plant P uptake and use efficiency under LP stress. Taken together, our results show that GmERF1 can affect root development by regulating hormone levels, thus promoting P absorption in soybean, and provide a better understanding of the role of GmERF1 in soybean P signal transduction. The favorable haplotypes from wild soybean will be conducive to the molecular breeding of high P use efficiency in soybean.


Assuntos
Glycine max , Fatores de Transcrição , Glycine max/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fósforo/metabolismo , Genótipo , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
3.
Opt Express ; 32(7): 12620-12635, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571080

RESUMO

A method based on deflectometry to measure the refractive index distribution of radial gradient refractive index (GRIN) lens is proposed in this paper. The method establishes the relationship between the refractive index distribution and the direction of light ray by deriving the propagation equation of light in a non-uniform medium. By measuring the deflection angle using the principle of deflectometry and the assumption of central refraction, the refractive index distribution of the radial GRIN lens is determined. The specific principle of refractive index measurement deflectometry (RIMD) is described in detail, and the correctness and accuracy of the method are verified through numerical simulations. Furthermore, the effects of calibration error, lens surface shape on the accuracy of the measurement results are analyzed. In the experimental section, the proposed method is applied to measure a radial GRIN lens, and the results are compared with the nominal parameters in terms of shape distribution and numerical values, demonstrating good consistency. The measurement error is controlled within the order of 10-3. This method enables rapid and convenient acquisition of full-field information of GRIN lens and holds promising potential for playing an important role in lens manufacturing and production.

4.
Opt Express ; 32(12): 21577-21593, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859508

RESUMO

Phase measuring deflectometry (PMD) is a key measurement technology for specular surfaces form measurement. Compared with conventional PMD techniques, the near optical coaxial PMD (NCPMD) can achieve compact configuration, light weight and reducing measurement error caused by shadows of the surface structures through utilizing a plate beamsplitter. However, the introduction of the plate beamsplitter will affect the measurement accuracy of the NCPMD system. The refraction of the plate beamsplitter needs to be considered. In this work, a virtual system of NCPMD was established, and an error model of the NCPMD system by considering the refraction influence of the plate beamsplitter was presented to analyze the shape reconstruction error caused by the plate beamsplitter. Moreover, the calibration method of the beamsplitter and the ray tracing algorithm to achieve error compensation of the beamsplitter were proposed. The proposed error compensation method can effectively improve the measurement accuracy of NCPMD system which has been confirmed by surface measurement experiments.

5.
Opt Lett ; 49(8): 2129-2132, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621093

RESUMO

This Letter presents the frequency-domain searching algorithm in deflectometry (FSAD). By encoding specialized multi-frequency fringe patterns and employing a correlation searching algorithm, the limitations of existing frequency-domain methods can be overcome to some extent, thereby separating front and back surface reflections to obtain complete measurement data. The principles of FSAD are described in detail. In the experiment, a piece of window glass with thickness of 10 mm and a square area of 96 × 96 mm is measured to verify the proposed method.

6.
Funct Integr Genomics ; 23(1): 37, 2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36639600

RESUMO

Carbonic anhydrases (CAs), as zinc metalloenzymes, are ubiquitous in nature and play essential roles in diverse biological processes. Although CAs have been broadly explored and studied, comprehensive characteristics of CA gene family members in the soybean (Glycine max) are still lacking. A total of 35 CA genes (GmCAs) were identified; they distributed on sixteen chromosomes of the soybean genome and can be divided into three subfamilies (α-type, ß-type, and γ-type). Bioinformatics analysis showed that the specific GmCA gene subfamily or clade exhibited similar characteristics and that segmental duplications took the major role in generating new GmCAs. Furthermore, the synteny and evolutionary constraints analyses of CAs among soybean and distinct species provided more detailed evidence for GmCA gene family evolution. Cis-element analysis of promoter indicated that GmCAs may be responsive to abiotic stress and regulate photosynthesis. Moreover, the expression patterns of GmCAs varied in different tissues at diverse developmental stages in soybean. Additionally, we found that eight representative GmCAs may be involved in the response of soybean to low phosphorus stress. The systematic investigation of the GmCA gene family in this study will provide a valuable basis for further functional research on soybean CA genes.


Assuntos
Anidrases Carbônicas , Glycine max , Glycine max/genética , Glycine max/metabolismo , Filogenia , Família Multigênica , Anidrases Carbônicas/genética , Anidrases Carbônicas/metabolismo , Biologia Computacional , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Genoma de Planta
7.
Plant Cell Environ ; 46(2): 592-606, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36419232

RESUMO

Phosphorus (P) deficiency seriously affects plant growth and development and ultimately limits the quality and yield of crops. Here, a new P efficiency-related major quantitative trait locus gene, GmEIL4 (encoding an ethylene-insensitive 3-like 1 protein), was cloned at qP2, which was identified by linkage analysis and genome-wide association study across four environments. Overexpressing GmEIL4 significantly improved the P uptake efficiency by increasing the number, length and surface area of lateral roots of hairy roots in transgenic soybeans, while interfering with GmEIL4 resulted in poor root phenotypic characteristics compared with the control plants under low P conditions. Interestingly, we found that GmEIL4 interacted with EIN3-binding F box protein 1 (GmEBF1), which may regulate the root response to low P stress. We conclude that the expression of GmEIL4 was induced by low-P stress and that overexpressing GmEIL4 improved P accumulation by regulating root elongation and architecture. Analysis of allele variation of GmEIL4 in 894 soybean accessions suggested that GmEIL4 is undergoing artificial selection during soybean evolution, which will benefit soybean production. Together, this study further elucidates how plants respond to low P stress by modifying root structure and provides insight into the great potential of GmEIL4 in crop P-efficient breeding.


Assuntos
Glycine max , Raízes de Plantas , Estudo de Associação Genômica Ampla , Fósforo/metabolismo , Raízes de Plantas/metabolismo , Locos de Características Quantitativas/genética , Glycine max/metabolismo , Proteínas de Plantas/metabolismo
8.
Opt Lett ; 48(7): 1714-1717, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221748

RESUMO

A method for the quantitative measurement of two-dimensional density field distributions based on deflectometry is proposed. With this method, from the point of view of the inverse Hartmann test, the light rays emitted from the camera reach the screen after being disturbed by the shock-wave flow field. After the coordinates of the point source are obtained by using the phase information, the deflection angle of the light ray can be calculated, and then the distribution of the density field can be determined. The principle of density field measurement deflectometry (DFMD) is described in detail. In the experiment, the density fields in wedge-shaped models with three different wedge angles are measured in supersonic wind tunnels, the experimental results from the proposed method are compared with the theoretical results, and the measurement error is found to be around 2.76 × 10-3kg/m3. This method has the advantages of fast measurement, a simple device, and low cost. It provides a new approach, to the best of our knowledge, to measuring the density field of a shock-wave flow field.

9.
Inorg Chem ; 62(32): 12620-12624, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37539839

RESUMO

A d-methionine-bonded nanosized arsenotungstate, Ba9K10H6[{As2W19O67(H2O)}2{AsW9O33}2{W3O6(H2O)(d-Met)}2{W2O4(OH)(d-Met)}]·60H2O [1; d-Met = d-methionine (C5H11NO2S)], is constructed without the use of lanthanide ions. The polyanion of 1 contains two {As2W19O67(H2O)}14- building blocks and two {B-ß-AsW9O33}9- subunits, integrated together with a {W2O4(OH)(d-Met)}2+ and two {W3O6(H2O)(d-Met)}5+ subclusters. Interestingly, 1 displays a highly reversible photocoloration property with a half-life (t1/2) time measured as about 0.793 min.

10.
J Periodontal Res ; 58(3): 520-528, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37042770

RESUMO

THE OBJECTIVE: This study aims to propose a new model to predict the specific treatment effectiveness at site level by analyzing massive amounts of periodontal clinical data with deep learning methods. THE BACKGROUND DATA DISCUSSING THE PRESENT STATUS OF THE FIELD: In light of the low accuracy of current tools, the proposed models cannot fully meet the needs of clinical effectiveness prediction and cannot be applied to on site level prognosis development and formulation of specific treatment plan. MATERIALS AND METHODS: Periodontal examination data of 9273 Chinese patients were extracted and used to propose a Sequence-to-Sequence model after performing data management and reconstruction. The model was optimized by introducing the Attention mechanism. RESULTS: In the test set, the model obtained an average site-level probing depth (PD) accuracy (defined as the proportion of sites with <1 mm deviation of the predicted result from the true value) of 92.4% and high sensitivity (98.6%) for the pocket closure variable. For sites with baseline PD <5 mm, the model achieved a prediction accuracy of 94.6%, while it decreased to 79.9% at sites with PD ≥5 mm. In contrast, for teeth with initial mean PD ≥5 mm, the prediction accuracy significantly differed between molars and non-molars. CONCLUSION: Our model is the first to predict the site-level effectiveness with high accuracy and sensitivity. Future prediction models should incorporate deep learning for improved clinical prediction.


Assuntos
Aprendizado Profundo , Humanos , Bolsa Periodontal/terapia , População do Leste Asiático , Prognóstico , Resultado do Tratamento
11.
Phys Chem Chem Phys ; 25(47): 32675-32687, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38010909

RESUMO

In this study, an efficient non-rare earth Mn4+-doped K3(NbOF5)(HF2) red fluorescent material was synthesized by using the coprecipitation method. Replacing KF with K2CO3 effectively solved the problem that KF was difficult to stir due to its strong water absorption. The sample was composed of rods. The excitation spectra consisted of two strong excitation peaks at 366 nm and 468 nm. The emission spectra consisted of a series of narrow-band emissions between 580 nm and 680 nm. Besides, the luminescence quantum efficiency (QE) reached 84.3% under the excitation of 468 nm. The fluorescent lifetime of K3(NbOF5)(HF2):Mn4+ was less than 4 ms, which can achieve fast response display in backlight display applications. The WLED was fabricated with K3(NbOF5)(HF2):Mn4+ and commercial YAG:Ce3+ and the commercial InGaN blue chip. At a 30 mA drive current, the WLED device exhibited excellent luminescence properties. The correlated color temperature (CCT) was 3853 K, the Ra was 90.1 and the luminous efficiency was 310.432 lm W-1. Therefore, K3(NbOF5)(HF2):Mn4+ has very broad prospects in WLED lighting and backlight display applications.

12.
BMC Musculoskelet Disord ; 24(1): 821, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848853

RESUMO

BACKGROUND: Treating complex cases of spinal tuberculosis (STB) that involve multiple vertebral bodies and cause destruction of the spinal structure, kyphotic deformity, and acute nerve injury can be challenging. This report describes the course of treatment and 5-year follow-up of a complex case of multisegmental STB. CASE PRESENTATION: This report describes a case of tuberculosis affecting the vertebrae extending from thoracic 12 to lumbar 5 in a 60-year-old woman who suffered sudden paralysis in both lower extremities. The patient underwent emergency posterior paraspinal abscess clearance, laminectomy with spinal decompression. Partial correction of the kyphotic deformity via long-segment fixation from the T9 vertebral body to the ilium in a one-stage posterior procedure. The patient's neurological status was diagnosed as grade E on the American Spinal Injury Association (ASIA) scale after the one-stage operation. Following standardized 4-combination anti-tuberculosis drug therapy for three months in postoperative patients, the patient underwent two-stage transabdominal anterior abscess removal, partial debridement of the lesion and bilateral fibula graft support. One year after the two-stage operation, the patient's visual analog scale (VAS) score of back pain was 1 point, and the patient's erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels returned to normal. Five years after the second-stage operation, the Oswestry disability index (ODI) of patient quality of life was 14 points. There was a 4-degree change in the Cobb angle over five years. During the five-year follow-up period, the grafted fibula did not experience any subsidence. CONCLUSION: For patients with spinal tuberculosis and acute paralysis, it is essential to relieve spinal cord compression as soon as possible to recover spinal cord function. For lesions that cannot be debrided entirely, although limited debridement combined with anti-tuberculosis drug therapy has the risk of sinus formation and tuberculosis recurrence, it is much safer than the risk of thorough debridement surgery. In this case, an unconventional long-segment fibula graft, pelvis-vertebral support, was an effective reconstruction method.


Assuntos
Cifose , Fusão Vertebral , Tuberculose da Coluna Vertebral , Feminino , Humanos , Pessoa de Meia-Idade , Tuberculose da Coluna Vertebral/complicações , Tuberculose da Coluna Vertebral/diagnóstico por imagem , Tuberculose da Coluna Vertebral/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Abscesso , Fíbula/diagnóstico por imagem , Fíbula/cirurgia , Qualidade de Vida , Resultado do Tratamento , Desbridamento/métodos , Fusão Vertebral/métodos , Cifose/cirurgia , Paralisia , Estudos Retrospectivos , Antituberculosos
13.
Opt Express ; 30(20): 35409-35430, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258493

RESUMO

As a highly accurate metrology, phase measuring deflectometry (PMD) can be used for in-situ surface shape measurement. However, due to the reflection off the back surface, PMD cannot measure both the front and back surfaces of the transparent planar element simultaneously. Therefore, this paper proposes a method for measuring the front and back surfaces of the transparent planar element. The phase distribution corresponding to the front and back surfaces can be firstly acquired by multi-frequency fringe deflectometry. Then, the front and back surface shapes can be obtained by inverse ray-tracing and nonlinear optimization. Numerical simulation and experiment verify the proposed method. The surface shape of window glass with a thickness of 10 mm is measured in the experiment. The surface shape error is around 50 nm in the root mean square with a diameter of 51 mm.

14.
Appl Opt ; 61(5): 1156-1163, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35201167

RESUMO

A camera calibration method for phase measuring deflectometry (PMD) based on the entrance pupil center (EPC) of the camera lens is proposed. In our method, the position of the entrance pupil of the camera lens is first measured; next the absolute coordinates of the EPC are calibrated by using a reference flat and an external stop that is mounted in front of the camera lens; then the EPC as the camera coordinates is used for PMD. The feasibility of the proposed method is verified by simulation. The surface shapes of a planar optical element and a planar window glass are separately measured in our experiments, and a subwavelength accuracy level is achieved. Meanwhile, the effects of the camera lens with different aperture settings on captured images are investigated (including exposure time, image contrast, and measurement accuracy). The experimental results show that the exposure time required declines with the decrease in the f-number, and the measurement accuracy is higher than others when the f-numbers are changed from f/5.6 to f/11.

15.
Planta ; 254(6): 110, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34716824

RESUMO

MAIN CONCLUSION: Soybean phosphorous efficiency QTLs were identified and candidate genes were predicted using chlorophyll fluorescence parameters through GWAS and RNA-seq. Phosphorus (P) is an essential nutrient element for crop growth and development, lack of P uptake seriously affects yield in various crops. Photosynthesis is the basis of crop production, while it is very sensitive to P deficiency. It is of great importance to study the genetic relationship between photosynthesis and P efficiency to provide genetic insight for soybean improvement. In this study, a genome-wide association study (GWAS) was performed using 292,035 SNPs and the ratios of four main chlorophyll fluorescence parameters of 219 diverse soybean accessions under P deficiency and normal P across three experiments. In total, 52 SNPs in 12 genomic regions were detected in association with the four main chlorophyll fluorescence parameters under sufficient or deficient P levels. Combined it with RNA-seq analysis, we predicted three candidate genes for the significant genomic regions. For example, the expression level of the candidate gene (Glyma.18g092900) in P deficiency tolerant accession was three times higher than that of P deficiency sensitive one under phosphorous deficiency condition. This study provides insight into genetic links between photosynthetic and phosphorous efficiency and further functional analysis will provide valuable information for understanding the underlying genetic mechanism to facilitate marker-assisted breeding in soybean.


Assuntos
Estudo de Associação Genômica Ampla , Glycine max , Clorofila , Fósforo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único/genética , RNA-Seq , Glycine max/genética
16.
J Virol ; 94(17)2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32554695

RESUMO

Accessory genes occurring between the S and E genes of coronaviruses have been studied quite intensively during the last decades. In porcine epidemic diarrhea virus (PEDV), the only gene at this location, ORF3, encodes a 224-residue membrane protein shown to exhibit ion channel activity and to enhance virus production. However, little is known about its intracellular trafficking or about its function during PEDV infection. In this study, two recombinant PEDVs were rescued by targeted RNA recombination, one carrying the full-length ORF3 gene and one from which the gene had been deleted entirely. These viruses as well as a PEDV encoding a naturally truncated ORF3 protein were employed to study the ORF3 protein's subcellular trafficking. In addition, ORF3 expression vectors were constructed to study the protein's independent transport. Our results show that the ORF3 protein uses the exocytic pathway to move to and accumulate in the Golgi area of the cell similarly in infected and transfected cells. Like the S protein, but unlike the other structural proteins M and N, the ORF3 protein was additionally observed at the surface of PEDV-infected cells. In addition, the C-terminally truncated ORF3 protein entered the exocytic pathway but it was unable to leave the endoplasmic reticulum (ER) and ER-to-Golgi intermediate compartment (ERGIC). Consistently, a YxxØ motif essential for ER exit was identified in the C-terminal domain. Finally, despite the use of sensitive antibodies and assays no ORF3 protein could be detected in highly purified PEDV particles, indicating that the protein is not a structural virion component.IMPORTANCE Coronaviruses typically express several accessory proteins. They vary in number and nature, and only one is conserved among most of the coronaviruses, pointing at an important biological function for this protein. PEDV is peculiar in that it expresses just this one accessory protein, termed the ORF3 protein. While its analogs in other coronaviruses have been studied to different extents, and these studies have indicated that they share an ion channel property, little is still known about the features and functions of the PEDV ORF3 protein except for its association with virulence. In this investigation, we studied the intracellular trafficking of the ORF3 protein both in infected cells and when expressed independently. In addition, we analyzed the effects of mutations in five sorting motifs in its C-terminal domain and investigated whether the protein, found to follow the same exocytic route by which the viral structural membrane proteins travel, is also incorporated into virions.


Assuntos
Infecções por Coronavirus/veterinária , Exocitose , Interações Hospedeiro-Patógeno , Fases de Leitura Aberta , Vírus da Diarreia Epidêmica Suína/genética , Doenças dos Suínos/metabolismo , Doenças dos Suínos/virologia , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Animais , Engenharia Genética , Redes e Vias Metabólicas , Plasmídeos/genética , Transporte Proteico , Proteômica , Suínos , Proteínas Virais/química , Proteínas Virais/genética
17.
Opt Express ; 29(18): 28427-28440, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34614974

RESUMO

A method based on 3D digital image correlation (DIC) to measure the shape of specular surface is proposed. The proposed active speckle deflectometry (ASD) utilizes a stereo-camera system to monitor the liquid crystal display (LCD), which is deliberately moved during the measurement. Another testing camera (TC) is used to capture the single-shot speckle pattern displayed on the LCD screen after reflection by the test surface. With this proposal, the movement of the LCD screen can be arbitrary as long as the TC can capture the reflection of speckle pattern. The distance as well as the direction of the movement is not required to be known. The coordinates of the point source are determined by applying the 3D DIC technique with the monitoring stereo-cameras (MSC) before and after the movement of the LCD screen, then the slope and surface shape are obtained. The measurement accuracy of this method is evaluated by measuring a flat glass with a diameter of about 80 mm, compared with the measurement results of interferometer, the shape measurement difference is 0.278um in root mean square (RMS). The shape of two wafers is also measured, and the measurement results are compared to that of the traditional phase measuring deflectometry (PMD). ASD has the advantages of fast measurement, low cost, arbitrary LCD movement, tolerance for the out-of-plane shape of the LCD screen. It provides a new method for specular surface measurement.

18.
Appl Opt ; 60(6): 1705-1709, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33690507

RESUMO

In this paper, a method for measuring the radius of mean curvature (Rm) of the spherical surface based on phase measuring deflectometry is proposed. With our method, the average of the Rm in a small region is constrained by a preknown radius of curvature (Rp), and the height of an anchor point in this region can be calculated with iterative and optimization methods. Then both the height and slope data of the spherical surface can be obtained, and the Rm of each point of the spherical surface can be calculated by a differential geometric method. The feasibility of the proposed method is verified by simulation. In the experiment, a spherical surface with 88.652 mm radius of curvature is measured to demonstrate the effectiveness of this method, which can be used to accurately measure the Rm of each point on the spherical surface by online or in situ measurement.

19.
Macromol Rapid Commun ; 41(7): e1900622, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32077181

RESUMO

The most daunting challenge of solid polymer electrolytes (SPEs) is the development of materials with simultaneously high ionic conductivity and mechanical strength. Herein, SPEs of lithium bis-(trifluoromethanesulfonyl)imide (LiTFSI)-doped poly(propylene monothiocarbonate)-b-poly(ethylene oxide) (PPMTC-b-PEO) block copolymers (BCPs) with both blocks associating with Li+ ions are prepared. It is found that the PPMTC-b-PEO/LiTFSI electrolytes with double conductive phases exhibit much higher ionic conductivity (2 × 10-4 S cm-1 at r.t.) than the BCP electrolytes with a single conductive phase. Concurrently, the storage moduli of PPMTCn -b-PEO44 /LiTFSI electrolytes are ≈1-4 orders of magnitude higher than that of the neat PEO/LiTFSI electrolytes. Therefore, simultaneous improvement of ionic conductivity and mechanical properties is achieved by construction of a microphase-separated and disordered structure with double conductive phases.


Assuntos
Nanopartículas/química , Polímeros/química , Condutividade Elétrica , Fontes de Energia Elétrica , Eletrólitos/química , Lítio/química , Compostos Organometálicos/química , Estresse Mecânico
20.
Opt Express ; 27(18): 25395-25409, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31510412

RESUMO

A method based on digital image correlation (DIC) for the surface shape measurement of specular surface by shifting a speckle pattern, which is displayed on an LCD screen, is proposed in this paper. With this method, the deformed information of test surface is encoded within the displacement distribution between the two recorded speckle images before and after the speckle pattern shifted. The displacement distribution is calculated by the DIC algorithm, then the slope data and the surface shape are obtained. The principle and algorithm of speckle pattern shifting deflectometry (SPSD) are described in detail. The correctness and feasibility of the proposed method are verified by simulation, and the source of error is analyzed as well. Finally, the shape of an acrylic plastic plate and a silicon wafer are measured. The experimental result of the proposed method is compared with that of PMD, and the figure error is around 1µm RMS with a measured diameter of about 100mm. This method has the advantages of fast measurement, simple device, low cost and needlessness of reference element. It provides a new approach to measure the shape of specular surface.

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