Since the rings of the angular contact ball bearings (ACBBs) are typical highly sensitive quenching thin-walled structure, the microstructure and properties variation of the rings during the heat treatment process are often difficult to be controlled precisely, and then the service life of the bearings is reduced. Therefore, in this study, the combination of the numerical simulation and experimental was carried out during the quenching and tempering process of ACBBs (7008C), the phase transformation of the inner and outer ring during the heat treatment process were explored, and the law of the microstructure evolution and the mechanical properties variation were revealed. Firstly, based on the multi-field coupling theory of temperature, microstructure and stress-strain field, the numerical simulation model of the heat treatment process of the bearing rings was established.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
April 2024
Metal nanostructure arrays with large amounts of nano-gaps are important for surface enhanced Raman scattering applications, though the fabrications of such nanostructures are difficult due to the complex and multiple synthetic steps. In this research, we report silver nanostructure array patterns (SNAPs) on silicon wafer, which is fabricated with semiconductor manufacturing technology, CuO electrochemistry deposition, and Ag In-situ oxidation-reduction growth. Benefiting from the dense and uniform distribution of Ag nanowires, the fabricated SNAPs demonstrate a very strong and uniform surface-enhanced Raman scattering (SERS) effect.
View Article and Find Full Text PDFAge and sex have effect on atherosclerosis. This study aimed to investigate their effect on non-stenotic intracranial atherosclerotic plaque (NIAP) in embolic stroke of undetermined source (ESUS) using high-resolution magnetic resonance imaging (HR-MRI). We retrospectively recruited consecutive ESUS patients who underwent intracranial HR-MRI to assess the plaque characteristics (remodeling index [RI], plaque burden [PB], fibrous cap [FC], discontinuity of plaque surface [DPS], intraplaque hemorrhage [IPH] and complicated plaque [CP]).
View Article and Find Full Text PDFTo evaluate the association of intracranial non-stenotic atherosclerotic plaque with cerebral small vessel disease (CSVD) imaging markers in a CSVD population using 3.0 T high-resolution magnetic resonance imaging (HRMRI), which was validated in embolic stroke of undetermined source (ESUS) cohort. We retrospectively recruited consecutive patients who were diagnosed with CSVD or ESUS from January 2015 to December 2019.
View Article and Find Full Text PDFObjective: To determine the characteristics of intracranial plaque proximal to large vessel occlusion (LVO) in stroke patients without major-risk cardioembolic source using 3.0 T high-resolution MRI (HR-MRI).
Methods: We retrospectively enrolled eligible patients from January 2015 to July 2021.
Background And Purpose: The association between nonstenotic plaque at the petrous internal carotid artery (ICA) and embolic stroke of undetermined source (ESUS) remains unknown. We aimed to test the hypothesis that the presence of a larger build-up of petrous plaque is more prevalent in the ipsilateral versus the contralateral side among ESUS patients without plaque in the intracranial and proximal ICA.
Methods: From a total of 243 patients with ESUS and 160 patients with small-vessel disease (SVD) without proximal ICA plaque, we enrolled 88 ESUS and 103 SVD patients without ipsilateral nonstenotic intracranial and proximal ICA plaque in the present study.
Background The potential causes or sources of embolic stroke of undetermined source (ESUS) vary. This study aimed to investigate the main cause of deep ESUS by evaluating nonstenotic intracranial atherosclerotic plaque. Methods and Results We retrospectively screened consecutive patients with unilateral anterior circulation ESUS.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
October 2022
A new MoWS two-dimensional nanosheets were prepared by the one-pot method. After certain Mo atoms in MoS were replaced by W ones in a hydrothermal reduction procedure, MoWS was formed on the Mo foil. Well enhanced MoWS nanosheets were prepared when the sodium tungstate concentration got under control.
View Article and Find Full Text PDFBackground And Purpose: The aim was to investigate the characteristics of non-stenotic intracranial plaque (NSIP) in embolic stroke of undetermined source (ESUS) subtypes by high-resolution magnetic resonance imaging.
Methods: Consecutive patients with ESUS who were mandatory for high-resolution magnetic resonance imaging were retrospectively enrolled. Based on the location and arterial supply of the infarct, the ESUS were categorized into three types: cortical ESUS, subcortical ESUS and mixed ESUS.
Objective: To assess (1) the association between atrial cardiopathy (AC) and non-stenotic intracranial complicated atherosclerotic plaque (NICAP) in patients with embolic stroke of undetermined source (ESUS) or small-vessel disease (SVD), and (2) the performance of previously proposed biomarkers to identify AC as the underlying aetiology in ESUS.
Methods: Based on our high-resolution MRI (HR-MRI) cohort, 403 subjects (243 ESUS and 160 SVD) were enrolled in the final analysis. All patients underwent intracranial HR-MRI to assess the presence of ipsilateral NICAP.
Spectrochim Acta A Mol Biomol Spectrosc
February 2022
Sensitive and selective detection of target analyte is very important in many fields such as commodity inspection and quality monitoring. In this work, based on the principle of competitive immunoassay, surface-enhanced Raman spectroscopy (SERS) was used to establish a rapid and highly sensitive method for the detection of trace amounts of bisphenol A in water. Here, Raman molecule 5,5-dithiobis-2-nitrobenzoic acid and anti-BPA antibody were conjugated with Au (core)@Ag (shell) nanoparticle to serve as SERS nanoprobe.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2022
Pesticide detection is of tremendous importance in agriculture, and Raman spectroscopy/Surface-Enhanced Raman Scattering (SERS) has proven extremely effective as a stand-alone method to detect pesticide residues. Machine learning may be able to automate such detection, but conventional algorithms require a complete database of Raman spectra, which is not feasible. To bypass this problem, the present study describes a transfer learning method that improves the algorithm's accuracy and speed to extract features and classify Raman spectra.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
July 2021
The silver nanoparticles have been frequently used in SERS detection, for their unique optical properties and sensitive surface Raman enhancement properties. However, as the preparation of silver nanoparticles will use polyvinylpyrrolidone (PVP) to achieve the effect of reducing agent and surfactant, the surface of the prepared silver nanoparticles will be wrapped by PVP, forming an insulating layer and an ill-defined AgNPs interface, which limits the plasmonic coupling between the laminates of AgNPs. This paper reported a simple method to remove PVP for high performance and reusable SERS substrate, and the residue of PVP was studied after clean centrifugal by ethanol or water.
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