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1.
BMC Genomics ; 25(1): 67, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233751

RESUMEN

BACKGROUND: Rye (Secale cereale), one of the drought and cold-tolerant crops, is an important component of the Triticae Dumortier family of Gramineae plants. Basic helix-loop-helix (bHLH), an important family of transcription factors, has played pivotal roles in regulating numerous intriguing biological processes in plant development and abiotic stress responses. However, no systemic analysis of the bHLH transcription factor family has yet been reported in rye. RESULTS: In this study, 220 bHLH genes in S. cereale (ScbHLHs) were identified and named based on the chromosomal location. The evolutionary relationships, classifications, gene structures, motif compositions, chromosome localization, and gene replication events in these ScbHLH genes are systematically analyzed. These 220 ScbHLH members are divided into 21 subfamilies and one unclassified gene. Throughout evolution, the subfamilies 5, 9, and 18 may have experienced stronger expansion. The segmental duplications may have contributed significantly to the expansion of the bHLH family. To systematically analyze the evolutionary relationships of the bHLH family in different plants, we constructed six comparative genomic maps of homologous genes between rye and different representative monocotyledonous and dicotyledonous plants. Finally, the gene expression response characteristics of 22 ScbHLH genes in various biological processes and stress responses were analyzed. Some candidate genes, such as ScbHLH11, ScbHLH48, and ScbHLH172, related to tissue developments and environmental stresses were screened. CONCLUSIONS: The results indicate that these ScbHLH genes exhibit characteristic expression in different tissues, grain development stages, and stress treatments. These findings provided a basis for a comprehensive understanding of the bHLH family in rye.


Asunto(s)
Genoma de Planta , Secale , Secale/genética , Filogenia , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/química , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
Sci Total Environ ; 916: 170199, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266729

RESUMEN

Herein, the adsorption performance of sulfate ion in water on aluminum nitride nanotube(AlNNT) under the influence of an electric field was investigated using the density functional theory (DFT) calculation method. The model structure stability, adsorption energy, electronic and thermodynamic properties of sulfate ion adsorbed on the surface of AlNNT were studied. The calculation results indicate that sulfate ion reacts with multi-atoms on the surface of AlNNT, forming ionic bonds and undergoing chemical adsorption. As the electric field intensity increases, the adsorption energy and the transfer of electrons from sulfate ion to AlNNT increase, leading to a higher degree of hybridization of atomic orbitals and enhanced multi-atom interactions. Additionally, the thermodynamic data suggests that the adsorption between sulfate ion and AlNNT under electric field can occur spontaneously, the process of which is exothermic. The results of present study are expected to propose a novel method for separation and removal of sulfate pollutants from water.

3.
Langmuir ; 39(45): 16035-16047, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37910596

RESUMEN

In this study, calculations based on density functional theory (DFT) were utilized to examine how electrostatic fields affect the electrical and optical characteristics of g-C3N4/TiO2 heterostructures. The binding energy, density of states, difference in charge density, and optical absorption spectra of the heterostructure were calculated and analyzed to reveal the mechanism of the influence of the external electric field (EF) on the properties of the heterostructure. The results show that the binding energy of the heterogeneous structure is reduced due to the imposed electric field in X- and Y-directions, and the optical absorption spectrum is slightly enhanced, but the BG and charge transfer number are basically unchanged. On the contrary, applying the electric field in the Z-direction increases the binding energy of the heterogeneous structure, decreases the BG, increases the number of charge transfers, and red shifts the optical absorption spectrum, which improves the photocatalytic ability of the g-C3N4/TiO2 heterostructure.

4.
Int J Neurosci ; : 1-11, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37902510

RESUMEN

Neurodevelopment can be precisely regulated by epigenetic mechanisms, including DNA methylations, noncoding RNAs, and histone modifications. Histone methylation was a reversible modification, catalyzed by histone methyltransferases and demethylases. So far, dozens of histone lysine demethylases (KDMs) have been discovered, and they (members from KDM1 to KDM7 family) are important for neurodevelopment by regulating cellular processes, such as chromatin structure and gene transcription. The role of KDM5C and KDM7B in neural development is particularly important, and mutations in both genes are frequently found in human X-linked mental retardation (XLMR). Functional disorders of specific KDMs, such as KDM1A can lead to the development of neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). Several KDMs can serve as potential therapeutic targets in the treatment of neurodegenerative diseases. At present, the function of KDMs in neurodegenerative diseases is not fully understood, so more comprehensive and profound studies are needed. Here, the role and mechanism of histone demethylases were summarized in neurodevelopment, and the potential of them was introduced in the treatment of neurodegenerative diseases.

5.
J Mol Model ; 29(9): 286, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37610510

RESUMEN

CONTEXT: Pectin methylesterase inhibitor (PMEI) can specifically bind and inhibit the activity of pectin methylesterase (PME), which has been widely used in fruit and vegetable juice processing. However, the limited three-dimensional structure, unclear action mechanism, low thermal stability and biological activity of PMEI severely limited its application. In this work, molecular recognition and conformational changes of PME and PMEI were analyzed by various molecular simulation methods. Then suggestions were proposed for improving thermal stability and affinity maturation of PMEI through semi-rational design. METHODS: Phylogenetic trees of PME and PMEI were established using the Maximum likelihood (ML) method. The results show that PME and PMEI have good sequence and structure conservation in various plants, and the simulated data can be widely adopted. In this work, MD simulations were performed using AMBER20 package and ff14SB force field. Protein interaction analysis indicates that H-bonds, van der Waals forces, and the salt bridge formed of K224 with ID116 are the main driving forces for mutual molecular recognition of PME and PMEI. According to the analyses of free energy landscape (FEL), conformational cluster, and motion, the association with PMEI greatly disrupts PME's dispersed functional motion mode and biological function. By monitoring the changes of residue contact number and binding free energy, IG35M/ IG35R: IT93F and IT113W/ IT113W: ID116W mutations contribute to thermal stability and affinity maturation of the PME-PMEI complex system, respectively. This work reveals the interaction between PME and PMEI at the gene and protein levels and provides options for modifying specific PMEI.


Asunto(s)
Hidrolasas de Éster Carboxílico , Filogenia , Hidrolasas de Éster Carboxílico/genética , Simulación por Computador , Mutación
6.
Sensors (Basel) ; 23(14)2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37514559

RESUMEN

In most of the piezoelectric stacked motors studied, the stator usually adopts two compound modes to drive the rotor to do step motion. This design method not only improves the utilization rate of the stator but also improves the torque output to a certain extent and increases the output displacement. In this study, a new type of multi-degree of freedom piezoelectric actuator is proposed for the utilization of a stator. The actuator realizes three compound vibration modes of bending-longitudinal-bending on a single stator, which changes the two compound modes of longitudinal bending and also changes the single motion mode of the stepper motor along a straight line. The rotor is set as a ball to drive it to rotate. The designed motor presents a different driving signal under which the rotor will no longer be accompanied by a return displacement. The finite element method is used to complete the design analysis, and the experimental analysis of the designed motor is carried out after the prototype is made. The multi-degree-of-freedom piezoelectric actuator can achieve a speed of 8.56 mm/c and a driving load of 1200 g at a voltage of 400 v and a working frequency of 42.7 kHz.

7.
Langmuir ; 39(22): 7648-7659, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37222045

RESUMEN

To improve the methane (CH4) storage performance of graphene oxide (GO), molecular dynamics (MD) simulations and density functional theory (DFT) calculation were employed to investigate the effect of electric field (EF) on the adsorption and desorption performances of monolayer graphene modified with three oxygen-containing functional groups (hydroxyl, carboxyl, and epoxy) as the CH4 storage material. Through the calculation and analysis of the radial distribution function (RDF), adsorption energy, adsorption weight percentage, and the amount of CH4 released, the mechanisms of influence on adsorption and desorption performances caused by an external EF were revealed. The study results showed that the external EF can significantly enhance the adsorption energy of CH4 on hydroxylated graphene (GO-OH) and carboxylated graphene (GO-COOH), making it easier to adsorb CH4, and improve the adsorption capacity. Whereas the EF severely weakened the adsorption energy of CH4 on epoxy-modified graphene (GO-COC) and reduced the adsorption capacity of GO-COC. For the desorption process, applying the EF can decrease the CH4 release of GO-OH and GO-COOH but increase the CH4 release of GO-COC. To sum up, when an EF is present, the adsorption properties of -COOH and -OH and desorption properties of -COC will be improved, but the desorption properties of -COOH and -OH and the adsorption properties of -COC will be weakened. The findings in this study are expected to propose a novel non-chemical method to improve the storage capacity of GO for CH4.

8.
Foods ; 12(5)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36900444

RESUMEN

The leaves of Engelhardia roxburghiana Wall (LERW) has been used as sweet tea in China throughout history. In this study, the ethanol extract of LERW (E-LERW) was prepared and the compositions were identified by HPLC-MS/MS. It indicates that astilbin was the predominant component in E-LERW. In addition, E-LERW was abundant in polyphenols. Compared to astilbin, E-LERW presented much more powerful antioxidant activity. The E-LERW also had stronger affinity with α-glucosidase and exerted more vigorous inhibitory effect on the enzyme. Alloxan-induced diabetic mice had significantly elevated glucose and lipid levels. Treatment with E-LERW at the medium dose (M) of 300 mg/kg could reduce the levels of glucose, TG, TC, and LDL by 16.64%, 12.87%, 32.70%, and 22.99%, respectively. In addition, E-LERW (M) decreased food intake, water intake, and excretion by 27.29%, 36.15%, and 30.93%, respectively. Moreover, E-LERW (M) therapy increased the mouse weight and insulin secretion by 25.30% and 494.52%. With respect to the astilbin control, E-LERW was more efficient in reducing the food and drink consumption and protecting pancreatic islet and body organs from alloxan-induced damage. The study demonstrates that E-LERW may be a promising functional ingredient for the adjuvant therapy of diabetes.

9.
J Neuropathol Exp Neurol ; 82(5): 412-418, 2023 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-36921281

RESUMEN

Abnormal histone methylation plays a key role in glioma development but the clinical value of specific alterations is still unclear. Here, the potential significance of histone H3 lysine 36 dimethylation (H3K36me2) was investigated as a biomarker for glioma. Seventy-three glioma patients were included in the study and the level of H3K36me2 in the tumor tissues was determined by immunohistochemistry. The χ2 test was used to explore the influence of clinical and pathological characteristics on H3K36me2 levels. The Kaplan-Meier method was used to estimate progression-free survival (PFS) and overall survival (OS). COX regression was used to explore the relationship between H3K36me2 levels and glioma prognosis. The results indicated that the H3K36me2 level increases with glioma grade. The proportion of high H3K36me2 levels was lower in glioma patients under the age of 52 years. H3K36me2 levels were negatively correlated with IDH1 mutation and MGMT promoter methylation, and positively correlated with p53 expression. Thus, high H3K36me2 levels positively correlated with poor prognosis of gliomas. In conclusion, H3K36me2 may be considered as a potential biomarker for glioma diagnosis, grading, and prognosis, but the overall clinical value of H3K36me2 determination deserves further investigation. These results may have important implications for accurate diagnosis and future precision treatment of gliomas.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Persona de Mediana Edad , Histonas/genética , Lisina/genética , Neoplasias Encefálicas/genética , Metilación de ADN , Glioma/genética , Pronóstico , Biomarcadores/metabolismo , Clasificación del Tumor , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Mutación
10.
Chemosphere ; 311(Pt 1): 137011, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36330976

RESUMEN

In this article, molecular dynamics simulations were used to examine the feasibility of capacitive deionization (CDI) system combined with a functionalized nanoporous graphene (NPG) membrane for removing methanol from water. The radial distribution function of electrode-methanol and methanol-water, the self-diffusion coefficient of methanol and water, the water density near the membrane, the interaction energy between methanol and membrane, the hydrogen bond structure between methanol and water, and the 2D density map of methanol molecules near the membrane under different electric field (EF) (to simulate the effect of capacitance) were examined to evaluate the separation performance of NPG membranes with hydrogen-passivated pores for methanol. The findings show that an EF with appropriate strength can decrease the amount of water molecules near methanol, increase the self-diffusion coefficient of methanol and water, increase hydrophobicity of hydrogenated pores, decrease the interaction between the NPG membrane and methanol, and weaken hydrogen bond interaction between water and methanol molecules. All these findings suggest that an appropriate EF can improve the NPG membrane's permeability to methanol, and verify the feasibility of CDI system combined with hydrogenated NPG membrane to remove methanol from water. This study is expected to propose a potential CDI application technology, and also give a novel idea for the removal of small organic molecules in water by functionalized NPG membrane.


Asunto(s)
Grafito , Nanoporos , Purificación del Agua , Agua , Metanol , Electrodos
11.
Front Genet ; 13: 967113, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105095

RESUMEN

Recently, the species of the insect order Phasmatodea, have attracted the interest of more and more enthusiasts. Here, we obtained the complete mitochondrial genome of Ramulus irregulatiter dentatus (R. irregulatiter dentatus), which belongs to the subfamily of Phasmatidae, detected by Illumina next-generation sequencing. The entire mitochondrial genome is 16,060 bp in length and contains a standard set of 13 protein-coding genes, 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and a putative A + T-rich region. The base composition and codon usage were typical of Phasmatodea species. The mitochondrial gene organization (37 genes) was consistent with that of other Phasmatidae. A phylogenetic tree was built from the sequence information of the 13 protein-coding genes by Bayesian analyses. The newly sequenced R. irregulatiter dentatus was most closely related to the family Phasmatidae. The complete mitochondrial genome of R. irregulatiter dentatus also provides valuable molecular information for future studies on Phasmatidae insect taxonomy and a framework to unveil more of their cryptic and unknown diversity, so that it can be used to control forest pests and protect crops.

12.
Curr Protein Pept Sci ; 23(10): 684-696, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36121086

RESUMEN

As an important pectin enzyme, pectin methylesterase (PME) can hydrolyze methyl esters, release methanol and reduce esterification. It is essential in regulating pollen tube development, root extension, and fruit ripening. Pectin methylesterase inhibitors (PMEI) can specifically bind PME and inhibit its activity, which jointly determines the esterification degree of pectin. PMEI has important application prospects in plant pest control, fruits and vegetable processing fields. In this paper, the gene families, crystal structures, molecular recognition, and applications in plants and industry are reviewed for the PME and PMEI systems. Finally, the semi-rational design of PMEI is discussed and discussed prospected.


Asunto(s)
Hidrolasas de Éster Carboxílico , Pectinas , Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Pectinas/química , Pectinas/metabolismo , Plantas/metabolismo , Inhibidores Enzimáticos/química
13.
Life (Basel) ; 12(9)2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36143446

RESUMEN

Environmental factors are the major constraints in sustainable agriculture. WRKY proteins are a large family of transcription factors (TFs) that regulate various developmental processes and stress responses in plants, including cotton. On the basis of Gossypium raimondii genome sequencing, WRKY TFs have been identified in cotton and characterized for their functions in abiotic stress responses. WRKY members of cotton play a significant role in the regulation of abiotic stresses, i.e., drought, salt, and extreme temperatures. These TFs either activate or repress various signaling pathways such as abscisic acid, jasmonic acid, salicylic acid, mitogen-activated protein kinases (MAPK), and the scavenging of reactive oxygen species. WRKY-associated genes in cotton have been genetically engineered in Arabidopsis, Nicotiana, and Gossypium successfully, which subsequently enhanced tolerance in corresponding plants against abiotic stresses. Although a few review reports are available for WRKY TFs, there is no critical report available on the WRKY TFs of cotton. Hereby, the role of cotton WRKY TFs in environmental stress responses is studied to enhance the understanding of abiotic stress response and further improve in cotton plants.

14.
Org Biomol Chem ; 20(35): 7011-7016, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36000782

RESUMEN

Herein, an economical copper-catalyzed reaction of α,ß-unsaturated N-tosylhydrazones with diaryliodonium salts to construct both N-arylpyrazoles and diaryl sulfones has been developed. Both the p-toluenesulfonyl anion and the 3-arylpyrazole intermediates were formed in situ from N-tosylhydrazones. Subsequently, the former reacted rapidly with diaryliodonium salts to give diaryl sulfones and aryl iodide intermediates, and the latter reacted with aryl iodide to give N-arylpyrazoles under copper-catalyzed conditions. Using unsymmetrical mesityl phenyliodonium salts as substrates, mesityl p-toluenesulfide was obtained as the major product. This reaction took full advantage of the "waste" part of substrates to form an extra diaryl sulfone.


Asunto(s)
Cobre , Sales (Química) , Catálisis , Yoduros , Sulfonas
15.
Neoplasma ; 69(5): 1019-1028, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35900318

RESUMEN

Systematic treatments including chemotherapy, endocrine therapy, and HER2-targeted therapy are important therapeutic approaches to breast cancer. However, drug resistance is a major barrier to achieving a cure in breast cancer (BC) patients. Hence, it is urgent to gain insight into the drug-resistance mechanisms in order to improve the prognosis of BC patients. Genetic alternations, epigenetic alternations, and other non-genetic mechanisms such as BC stem-like cells, metabolic reprogramming, and tumor microenvironment contribute to drug resistance of BC. With the development of single-cell sequencing of circulating tumor cell and next-generation sequencing of matched pre- and post- progression tumor biopsies or ctDNA from BC patients with drug resistance, new mechanisms of resistance are being discovered. An increasing number of microRNAs and long non-coding RNAs have been found to be associated with the drug resistance of BC. However, there are few reports on the role of circular RNAs (circRNAs) as master regulators of drug resistance. Therefore, there is still much to say in the field of drug resistance-related circRNAs. In this review, we mainly focus on literature evidence for the detailed mechanisms associated with systematic treatments' resistance of BC and how circRNAs intensify or weaken drug resistance. Exogenous expression of tumor suppressive circRNAs or knockdown of oncogenic circRNAs has been verified to reverse drug resistance of BC cells, which highlights that circRNAs may function as potential biomarkers and/or therapeutic targets of BC. Treatment targeting abnormally expressed circRNAs alone or combined with other systemic treatments may be a promising approach to conquering drug resistance.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Biomarcadores , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Humanos , MicroARNs/genética , Pronóstico , ARN Circular/genética , Microambiente Tumoral
16.
Sci Total Environ ; 848: 157710, 2022 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-35908697

RESUMEN

Ozone is the main role of ozone-based advanced oxidation process for organic wastewater treatment, which is usually added in water by aeration. However, the low solubility of ozone in water seriously affects the degradation efficiency. In this article, the external electrostatic field (EF) was proposed to improve the ozone solubility in water. The mass transfer characteristics of ozone in a gas-liquid two-phase system under EF were studied by molecular dynamics (MD) simulation. The microscopic mechanism of ozone mass transfer in water promoted by external EF was revealed by analyzing Gibbs dividing surface (GDS) interface structure, interfacial water molecular orientation, surface tension, liquid phase viscosity, hydrogen bond network and ozone self-diffusion coefficient. Our findings reveal that EF can enhance the thickness of GDS region (from 0.4648 nm to 0.4996 nm when EF is 0.2 V/nm) as well as its ozone content. The dipole moment orientation of water molecules also tends to point in the EF direction due to the influence of EF, making the difference in dipole moment orientation of water molecules in the first and second layers of GDS region gradually disappear. In addition, compared with the absence of EF, the existence of external EF can decrease the surface tension (from 77.6162 mN/m to 73.3480 mN/m when EF is 0.2 V/nm) at the gas-liquid interface and the viscosity of liquid phase (from 0.293 mPa·s to 0.162 mPa·s when EF is 0.2 V/nm), break the network of hydrogen bond in liquid phase, and increase the mobility of ozone (self-diffusion coefficient of ozone changes from 1.3232 × 10-6 cm2·s-1 to 1.8812 × 10-6 cm2·s-1 when EF is 0.2 V/nm). All these properties changes indicate that the presence of external EF enhances the ability of ozone to penetrate the interface of the two-phase system, and then improves the ozone mass transfer efficiency in water.


Asunto(s)
Ozono , Agua , Simulación de Dinámica Molecular , Ozono/química , Solubilidad , Electricidad Estática , Agua/química
17.
Micromachines (Basel) ; 13(6)2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35744516

RESUMEN

In view of the frequent safety problems of electric vehicles, the research on accurately obtaining the rotor position of the motor through the resolver is an important means to improve the functional safety of the system. The commonly used resolver decoding method involves the resolver decoding chip method and software decoding method, but few studies integrate the two decoding methods. A single method of motor rotor position acquisition cannot meet the requirements of system functional safety. To fill this gap, this paper proposes a method to simultaneously integrate hardware decoding and software decoding in the motor control system. The decoding chip and software decoding obtain the angle data at the same time, and they provide redundancy to improve the functional safety of the electronic control system. Finally, the effectiveness of the proposed simultaneous operation of hardware decoding and software decoding is verified by experiments.

18.
Micromachines (Basel) ; 13(6)2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35744568

RESUMEN

Piezoelectric-driven multi-degree-of-freedom motors can turn off self-lock, withstand high and low temperatures, are small in size and compact in structure, and can easily achieve miniaturization. However, they have a short life cycle and limited applications. In addition, high-intensity operation will result in a decrease in their stability. Electromagnetic-driven multi-degree-of-freedom motors, on the other hand, are simple and highly integrated, but they are large in volume and lack positioning accuracy. Therefore, combining the two drive modes can achieve complementary advantages, such as improving the motor's torque, accuracy, and output performance. Firstly, the structure of the hybrid drive motor is introduced and its working principle is analyzed. The motor can achieve single and hybrid drive control, which is beneficial to improving the performance of the motor. Secondly, the influence of magnetization mode, permanent magnet thickness, slot torque, and stator mode on the motor is analyzed. Thirdly, the structure of the motor is determined to be 6 poles and 15 slots, the thickness of the permanent magnet is 12 mm, and the radial magnetization mode is used. Finally, the mixed torque and speed of the motor in the multi-degree-of-freedom direction are tested by experiments, which indirectly verifies the rationality of the structure design.

19.
Micromachines (Basel) ; 13(6)2022 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35744581

RESUMEN

Temperature rise has always been one of the main researchfocusesof the motor. When the temperature is too high, it will have a serious impact on the stability and reliability of motor performance. Due to the special structure of electromagnetic piezoelectric hybrid drive motor (EPHDM), the loss and temperature distribution of electromagnetic drive part and piezoelectric drive part werestudied. By analyzing the operation principle of the motor, the loss of each part wasresearched. On this basis, the loss of the electromagnetic driving part and piezoelectric driving part werecomputed by using the coupling iterative calculation method. The temperature contour map of the motor wasanalyzed by simulation, and the temperature characteristics of each part of the motor werestudied. Finally, the experimental verification of the prototype, the reliability of the theoretical model, and simulation results wereproved. The results showed that the temperature distribution of the motor is reasonable, the winding temperature is relatively high, and the core temperature and piezoelectric stator temperature are relatively low. The analytical and experimental methods are provided for the further study of heat source optimization.

20.
Micromachines (Basel) ; 13(5)2022 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-35630128

RESUMEN

Laser detection technology has manypromising applications in the field of motor speed and position measurement. Accurate and fast measurement of position information of spherical rotor is very important for motor control. In this paper, we propose a method for non-contact measurement of the angular velocity of a multi-DOF spherical motor using the Doppler effect of the laser, and further obtain the position information of the motor rotor. The horizontal laser beam from the laser generator is divided into a reference beam I and a measurement beam II through a beam splitter, and the measurement beam II reflects and undergoes Doppler effect after irradiating the rotating motor. The two beams pass through the photoelectric conversion module to obtain the corresponding frequency difference signals to derive the angular velocity and position information of the motor rotor. The correctness of the method is verified experimentally. The results show that the coordinate error of Z and Y axes is less than 2 mm, thatthe error of Z-axes is less than 0.2 mm, and that the method can better measure the spherical rotor position information of the motor.

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