Micro & Nano Letters最新文献

{"title":"Machine Learning-Augmented Micro-Defect Detection on Plastic Straw","authors":"Zhisheng Zhang, Peng Meng, Yaxin Yang, Jian Zhu","doi":"10.3390/micro3020032","DOIUrl":"https://doi.org/10.3390/micro3020032","url":null,"abstract":"Plastic straws are well-known tools to assist human beings in drinking fluid, but most of them have micro-defects including black spot defects, head problems, pressure tube defects, and sealing wrinkles. The manual detection of these defects has drawbacks such as low efficiency, a high false detection rate, and excessive labor. This paper proposed machine vision-based detection with self-adaption and high-accuracy characteristics. A serial synthesis of algorithms including homomorphic filtering, Nobuyuki Otsu, and morphological opening operations is proposed to obtain plastic straws with binary images with good performance, and it was further found that the convolutional neural network can be designed to realize the real-time recognition of black spot defects, where the corner detection algorithm demonstrates the linear fitting of the edge point of the straw with the effective detection of sealing wrinkle defects. We also demonstrated that the multi-threshold classification algorithm is used to detect defects effectively for head problems and pressure tube defects. The detection system based on machine vision successfully overcomes shortcomings of manual inspection, which has high inspection efficiency and adaptively detects multiple defects with 96.85% accuracy. This research can effectively help straw companies achieve high-quality automated production and promotes the application of machine vision in plastic straw defects with the aid of machine learning.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87778011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nanometals and Metal Ion Pollution from Dental Materials in Dental Environment","authors":"A. C. B. Fernandes, R. França","doi":"10.3390/micro3020031","DOIUrl":"https://doi.org/10.3390/micro3020031","url":null,"abstract":"The dental environment is being polluted with metals from dental materials in many ways, mainly due to aerosol-generating procedures; this could affect the long-term well-being of dentists, dental students, and dental personnel. The current dental pollution incorporates metallic nanoparticles, which are highly reactive and quickly become airborne, especially those particles that become unbound in the bulk composition. In addition, liquid mercury or mercury vapors may be released from dental amalgam, causing concerns in the dental community. In our study, we reviewed the behavior of metallic elements present in dental materials, their routes of exposure, and their potentially toxic effects on the dental team. This review found that skin and lung disorders are the most harmful effects of metallic exposure for dentists, dental students, and dental personnel. Therefore, chronic exposure to low concentrations of metals in the dental environment, especially in nanosized forms, should be further investigated to improve the environmental matrix, material choice, and safety protocols.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"43 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88511061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Properties of Mechanochemically Synthesized Famatinite Cu3SbS4 Nanocrystals","authors":"E. Dutková, J. Kováč, J. Kováč, J. Hejtmánek, P. Levinský, A. Kashimbetova, M. Sayagués, M. Fabián, Z. Lukáčová Bujňáková, M. Baláž, Katarína Gáborová, V. Puchý, L. Čelko","doi":"10.3390/micro3020030","DOIUrl":"https://doi.org/10.3390/micro3020030","url":null,"abstract":"In this study, we report the optoelectric and thermoelectric properties of famatinite Cu3SbS4 that was mechanochemically synthesized in a planetary mill from powder elements for 120 min in an inert atmosphere. The tetragonal famatinite Cu3SbS4 was nanocrystalline with a crystallite size of 14 nm, as endorsed by Rietveld refinement. High-resolution transmission electron microscopy showed several crystallites in the range of 20–50 nm. Raman spectroscopy proved the purity of the synthesized famatinite Cu3SbS4 and chemical-state characterization performed by X-ray photoelectron spectroscopy confirmed that the prepared sample was pure. The Cu1+, Sb5+, and S2− oxidation states in Cu3SbS4 sample were approved. The morphology characterization showed homogeneity of the prepared sample. The photoresponse of Cu3SbS4 was confirmed from I–V measurements in the dark and under illumination. The photocurrent increase reached 20% compared to the current in the dark at a voltage of 5 V. The achieved results confirm that synthesized famatinite Cu3SbS4 can be applied as a suitable absorbent material in solar cells. The performed thermoelectric measurements revealed a figure of merit ZT of 0.05 at 600 K.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"27 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86145389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Designing Viscoelastic Gelatin-PEG Macroporous Hybrid Hydrogel with Anisotropic Morphology and Mechanical Properties for Tissue Engineering Application","authors":"K. Dey, S. Agnelli, L. Sartore","doi":"10.3390/micro3020029","DOIUrl":"https://doi.org/10.3390/micro3020029","url":null,"abstract":"The mechanical properties of scaffolds play a vital role in regulating key cellular processes in tissue development and regeneration in the field of tissue engineering. Recently, scaffolding material design strategies leverage viscoelasticity to guide stem cells toward specific tissue regeneration. Herein, we designed and developed a viscoelastic Gel-PEG hybrid hydrogel with anisotropic morphology and mechanical properties using a gelatin and functionalized PEG (as a crosslinker) under a benign condition for tissue engineering application. The chemical crosslinking/grafting reaction was mainly involved between epoxide groups of PEG and available functional groups of gelatin. FTIR spectra revealed the hybrid nature of Gel-PEG hydrogel. The hybrid hydrogel showed good swelling behavior (water content > 600%), high porosity and pore interconnectivity suitable for tissue engineering application. Simple unidirectional freezing followed by a freeze-drying technique allowed the creation of structurally stable 3D anisotropic macroporous architecture that showed tissue-like elasticity and was capable of withstanding high deformation (50% strain) without being damaged. The tensile and compressive modulus of Gel-PEG hybrid hydrogel were found to be 0.863 MPa and 0.330 MPa, respectively, which are within the range of normal human articular cartilage. In-depth mechanical characterizations showed that the Gel-PEG hybrid hydrogel possessed natural-tissue-like mechanics such as non-linear and J-shaped stress-strain curves, stress softening effect, high fatigue resistance and stress relaxation response. A month-long hydrolytic degradation test revealed that the hydrogel gradually degraded in a homogeneous manner over time but maintained its structural stability and anisotropic mechanics. Overall, all these interesting features provide a potential opportunity for Gel-PEG hybrid hydrogel as a scaffold in a wide range of tissue engineering applications.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"19 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86474001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Digitally Based Precision Time-Domain Spectrometer for NMR Relaxation and NMR Cryoporometry","authors":"J. Webber, Pavel Demin","doi":"10.3390/micro3020028","DOIUrl":"https://doi.org/10.3390/micro3020028","url":null,"abstract":"NMR Relaxation (NMRR) is an extremely useful quantitative technique for material science, particularly for studying polymers and porous materials. NMR Cryoporometry (NMRC) is a powerful technique for the measurement of pore-size distributions and total porosities. This paper discusses the use, capabilities and application of a newly developed compact NMR time-domain relaxation spectrometer suitable for studying both solid and liquid samples (Mk3 NMR Relaxation spectrometer & Cryoporometer, Lab-Tools (nano-science), Ramsgate, Kent, UK. (2019)). This highly compact precision NMR Spectrometer is based on a Field Programmable Gate array (FPGA) module and custom surface mount low-noise NMR receiver and NMR linear transmitter. A high proportion of the RF circuitry is in a digital form, implemented as firmware in the FPGA, which gives the instrument an excellent long-term stability. It also includes an on-chip Linux computer. The FPGA module is credit-card sized, and both the NMR receiver and NMR transmitter are even smaller. The software, including the top-level NMR pulse sequence definitions, are written in an array processing language, Apl. The spectrometer comes complete with a Graphical User Interface (GUI) for control and on- and offline curve fitting and data analysis. The recent development of the Lab-Tools Peltier thermo-electrically cooled NMR variable-temperature (V-T) probe that cools the sample below −60 °C is also discussed. This Peltier cooling gives the precision temperature control and smoothness needed by NMR Cryoporometry (10 mK near the probe liquid bulk melting point). This enables the NMRC measurement of pore-size distributions in porous materials, for the unusually wide pore-size range of sub-nano to over 1 micron-sized pores. The NMR Spectrometer’s unusually small size, ability to measure solids, low noise and high performance make it particularly suitable for material science studies both in the field and in university, research institute, company and even school laboratories. A human portable version now exists. Use of the controlling GUI is described, and results from example NMR Relaxation and NMR Cryoporometric measurements are given.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"14 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76669771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Functionalized CdSSe Quantum Dots in the CYP450 Activity of HEPG2 Cells","authors":"L. Alamo-Nole, Jury Cruz-Hernandez","doi":"10.3390/micro3020027","DOIUrl":"https://doi.org/10.3390/micro3020027","url":null,"abstract":"Quantum dots (QDs) have different properties: high electron density, magnetic moment, phosphorescence, photoluminescence (fluorescence), and strong optical absorption. The layer or ligands on the QDs surface has a vital role because they allow the stabilization and practical uses on different matrixes. Ligand exchange is a commonly carried out methodology to incorporate functional groups that alter the solubility, introduce electron transfer partners, integrate biological receptors, or improve the properties of the QDs surface. CdSSe QDs were synthesized using a microwave system using thioglycolic acid (TGA) as a sulfur source and cover agent. The TGA ligand was interchanged with cysteine (Cys), glutamic acid (GA), glutathione (GTO), glutaraldehyde (GLT), and lysine (Lys). The viability and response of the CYP1A1, CYP1A2, and CYP3A4 isoenzymes were directly measured in HEP-G2 cells after exposure to CdSSe-TGA, CdSSe-Cys, CdSSe-GA, CdSSe-GTO, CdSSe-GLT, and CdSSe-Lys. CdSSe and CdSSe-GTO (10 mg/L) decrease viability by around 65%. The response of the cytochrome isoenzymes is based on the organic ligand on the surface of the CdSSe QDs. Changes in CYP 1A1 could be related to carcinogenic xenobiotics. Fluorescence microscopy shows CdSSe QDs on and inside HEPG2 cells. The results confirm that apoptosis and necrosis are the principal mechanisms of decreased viability.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"73 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82876200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the biological activity of nanoemulsions fabricated by walnut oil (Juglans regia L.)","authors":"Somayeh Khezri,&nbsp;Sara Karimian,&nbsp;Ehsan Yousefi,&nbsp;Ali Es-haghi","doi":"10.1049/mna2.12161","DOIUrl":"https://doi.org/10.1049/mna2.12161","url":null,"abstract":"<p>Herbal medicines are currently attracting much attention as a potential cancer treatment. <i>Juglans regia</i>’s wide variety of anticancer actions have been demonstrated. The aim of this study is evaluating the cytotoxic and antioxidant effects of walnut oil (<i>J. regia</i>) nanoemulsion (WO-NE) on CT26 colon cancer cell line. The dimensions and structure of the nanoemulsion were studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The 1,1-Diphenyl-2-picrylhydrazyl (DPPH) technique was used to determine whether or not the nanoemulsions had any antioxidant properties. The cytotoxic effects of 3-[4,5-dimethylthiazol-2-yl-2-5-[diphenyltetrazolium bromide] (MTT) on CT26 colon cancer cells and umbilical vein endothelial cells (HUVEC) as normal cells were measured. The DPPH experiment demonstrated that the manufactured nanoemulsion had the ability to scavenge free radicals in a dose-dependent manner, with an IC₅₀ of approximately 500 µg/mL. The WO-NE were found to be toxic to both HUVEC and CT26 cancer cells, with an IC₅₀ of 10 ± 2.6 µg/mL for the CT26 and 160 ± 7.1 µg/mL for the HUVEC after 24 h of incubation. For comparison the effects of walnut oil also have been investigated. Due to their antioxidant and anticancer capabilities, the WO-NE synthesized here have been proposed for future study as potential anti-tumour agents.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"18 4","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12161","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50149287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodic Approach of Atomic-Force Microscopy (AFM) to Study Morphological Changes of Cells and Model Systems","authors":"V. Binyukov, E. Mil, L. Matienko, A. Albantova, A. Goloshchapov","doi":"10.3390/micro3020026","DOIUrl":"https://doi.org/10.3390/micro3020026","url":null,"abstract":"For the first time AFM (atomic-force microscopy) was used to record significant changes in the geometric parameters of the image of erythrocytes in vitro under conditions of glycolytic starvation (ATP (Adenosine triphosphate) deficiency). The difference in the action of antioxidants, phenosan K, and Ihfan-10 on erythrocytes that we detected with AFM seems to be mainly due to their difference in hydrophobicity. We used the AFM method to research the self-organization of the components of the active center of P450 (Porphyrin-450) metalloenzymes that are part of a class of hemoproteins with functions of affinity to molecular oxygen O2. Stable supramolecular nanostructures in the form of triangular prisms based on the iron porphyrin complex with amino acids due to self-assembly involving intermolecular hydrogen bonds were received. A possible scheme for the formation of such structures is proposed.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"73 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86246504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Mode of Preparation of Titanium Dioxide Nanotube Arrays on Their Photocatalytic Properties: Application to p-Nitroaniline Degradation","authors":"Nisreen Alshibeh Alwattar, F. Vacandio, L. Vassalo, T. Djenizian, B. Coulomb, J. Boudenne","doi":"10.3390/micro3010025","DOIUrl":"https://doi.org/10.3390/micro3010025","url":null,"abstract":"The aim of this study was to investigate the photoactivity of dioxide titanium (TiO2) nanotube films depending on different structure factors including pore size, tube length, tube wall thickness and crystallinity. Aqueous p-nitroaniline was used as a probe to assess the photocatalytic activity of titanium dioxide nanotube layers under UV irradiations. Self-organized titanium dioxide nanotube thin films were prepared by electrochemical anodization of titanium (Ti) foils and Ti thin films sputtered onto silicon (Si). The amorphous as-formed titanium nanotube layers were then annealed at different temperatures ranging from 450 to 900 °C in order to form crystalline phases. The structure and the morphology of the films were characterized by surface analysis techniques and scanning electron microscopy, respectively. The photocatalytic activity of the resulting TiO2 thin films was evaluated by monitoring the UV degradation of p-nitroaniline by UV spectrophotometry and by determining nitrification yields of by ion chromatography. The highest photocatalytic activity was exhibited for titanium nanotubes annealed at 450 °C. The presence of rutile -obtained for an annealing temperature of 900 °C—appeared to reduce the photodegradation yield of p-nitroaniline. Finally, the TiO2 nanotubes obtained from Ti foils revealed the most efficient photocatalytic properties.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82123689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of multilayer graphene doping concentrations on detection properties of MLG/Mg2Si/Si heterojunction photodetector","authors":"Hong Yu,&nbsp;Xichen Xiong,&nbsp;Zhangjie Mo,&nbsp;Rui Deng,&nbsp;Li Li,&nbsp;Deliang Chen","doi":"10.1049/mna2.12160","DOIUrl":"https://doi.org/10.1049/mna2.12160","url":null,"abstract":"<p>This paper presents a structural model for a photodetector (PD) with a multilayer graphene (MLG)/Mg₂Si/Si heterojunction and an examination of the impacts of MLG doping concentrations on the detection abilities of these PDs. The results show that under the conditions of different thicknesses of the monolayer, five-layer, and 10-layer grapheme (Gr), the detection properties of heterojunction PDs degrade as the doping concentrations of the MLG layer increase from 10¹³ to 10¹⁷ cm⁻³, respectively. The electric field intensity at the heterojunction MLG/Mg₂Si interface diminishes as MLG doping concentrations increase. The effectiveness of photo-generated carrier separation and transfer in the space charge area at the MLG/Mg₂Si interface therefore declines. The detection properties are outstanding when the MLG doping concentration is 10¹³ cm⁻³. The maximum values of peak responsivity, external quantum efficiency (EQE), detectivity (D*), and on/off ratio are found to be 0.81 A/W, 103.28%, 6.1×10¹⁰ Jones, and 610.5, respectively. A minimum peak noise equivalent power (NEP) of 1.64×10⁻¹¹ WHz^−1/2 is obtained. The results also show that PD has a great potential as a replacement for other visible and near-infrared (NIR) poisonous devices. The facts presented above provide a theoretical framework for the fabrication and application of optoelectronic devices.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"18 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12160","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50139930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}