Micro & Nano Letters最新文献

{"title":"The Influence of Fibre Cross Section Shape and Fibre Surface Roughness on Composite Micromechanics","authors":"J. Thomason","doi":"10.3390/micro3010024","DOIUrl":"https://doi.org/10.3390/micro3010024","url":null,"abstract":"Many of the carbon and natural fibres used in composite reinforcement have a non-circular cross section. Recently non-circular, or flat, cross section glass fibre products have become commercially available. This paper explores the potential effects that such non-circular fibre cross section shapes may have on the micromechanics of stress transfer at the composite fibre–matrix interface and the resulting changes in composite strength performance. Analytical modelling is used to show how the critical fibre length in composites with non-circular fibres is always less when compared to circular fibres with an equal cross-sectional area. This can result in significant changes to the strength performance of discontinuous fibre reinforced composites. Additionally, it is shown that the surface roughness found on natural and carbon fibres, many of which are also non-circular in cross section, can decrease the critical fibre length still further. These effects have important consequences for the use of single fibre micromechanical tests used for the characterisation of interfacial strength.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"21 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81185477","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":"The gut microbiota diversity of five Orthoptera (Insecta, Polyneoptera) insects determined by DNA metabarcoding.","authors":"Yantong Liu, Lina Zhao, Zhongying Qiu, Hao Yuan","doi":"10.3897/BDJ.11.e98162","DOIUrl":"10.3897/BDJ.11.e98162","url":null,"abstract":"<p><p>Most orthopteran insects are phytophagous and some are important pests in agriculture and forests. Many intestinal microflora of Orthoptera insects have been reported, primarily from Acridoidea and there have been few reports of other taxa. In this study, we collected 15 individuals representing five species (<i>Ruspolialineosa</i>, <i>Tetrixjaponica</i>, <i>Erianthusversicolor</i>, <i>Gryllotalpaorientalis</i> and <i>Teleogryllusemma</i>) belonging to five orthopteran superfamilies (Tettigonioidea, Tetrigoidea, Eumastacoidea, Gryllotalpoidea and Grylloidea) to characterise and compare the gut microbiota with greater taxonomic width by performing sequencing analysis of the 16S rRNA V4 region in gut material. A total of 606,053 high-quality sequences and 3,105 OTUs were acquired from 15 gut samples representing 24 phyla, 48 classes, 69 orders, 133 families and 219 genera. Firmicutes and bacteria were the most abundant phyla, followed by Bacteroidetes, Cyanobacteria, Actinobacteria and Acidobacteria. At the genus level, <i>Serratia</i>, <i>Citrobacter</i>, <i>Wolbachia</i>, <i>Lactobacillus</i> and <i>Parabacteroides</i> were the most predominant genera in <i>R.lineosa</i>, <i>T.japonica</i>, <i>E.versicolor</i>, <i>G.orientalis</i> and <i>T.emma</i>, respectively. Both Principal Coordinates Analysis (PCoA) and heatmap results revealed significant differences in bacterial community composition across species. Additionally, alpha diversity analysis indicated the bacterial richness was significantly different amongst the five species.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"12 1","pages":"e98162"},"PeriodicalIF":1.3,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10848783/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86272741","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":"Facile preparation of zinc nanoparticles mediated by plant aqueous extract and assessment of the antioxidant, cytotoxicity and anti-human bone carcinoma properties","authors":"Tao Li,&nbsp;Maohua Li","doi":"10.1049/mna2.12156","DOIUrl":"https://doi.org/10.1049/mna2.12156","url":null,"abstract":"<p>In this study, the Zn nanoparticles were synthesized using the peel extract of <i>Citrus aurantium</i>. The nanoparticles were characterized by different chemical techniques including UV-Vis. and FT-IR spectroscopy, and SEM technique. The results revealed a spherical shape with an average size of 41.17 nm was identified for the green-synthesized nanoparticles. In the antioxidant test, the IC₅₀ of nanoparticles and butylated hydroxytoluene (BHT) against DPPH free radicals were 115 and 96 μg/mL, respectively. In the cellular and molecular part of the recent study, the treated cells with nanoparticles were assessed by the MTT assay for 48 h about the cytotoxicity and anti-human bone cancer properties on normal (HUVEC) and cancer cell lines, that is, A-673 and HS-729. The IC₅₀ of nanoparticles were 278 and 256 μg/mL against A-673 and HS-729 cell lines, respectively. The viability of malignant cell lines reduced dose-dependently in the presence of Zn nanoparticles. It seems that the anti-cancer effect of recent nanoparticles is due to their anti-oxidant effects. After evaluating the effectiveness of this formulation in clinical trial researches, it can be a good alternative to chemotherapy drugs.</p>","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"18 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12156","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50134579","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":"The New Italian Standard on the Life Assessment of Martensitic Steels—First Results of the Experimental Validation Activity of XRD by Testing P91 and P92 Samples from Interrupted Uniaxial Creep Tests","authors":"A. Tonti, Pietro De Blasi","doi":"10.3390/micro3010020","DOIUrl":"https://doi.org/10.3390/micro3010020","url":null,"abstract":"The Italian Thermotechnical Committee is drafting a new standard for the life assessment of creep-operated pressure equipment, including modern steam boilers. For the evaluation of the spent life ratio several methods are available, even if each of them is not exhaustive. It should be noted that the methods described must be considered in combination with NDTs and other kinds of tests, e.g., hardness tests. X-ray diffraction (XRD) is one of the methods that could be used to assess material evolution under creep conditions. The method allows for the study of phase transitions involving structural variations. It is possible to operate on both massive samples and powders. In this paper, work done with XRD, in the frame of a wider project regarding the study of the high-temperature behavior of welded martensitic steels, is presented. The results of the XRD analysis were compared with the results of the extraction replicas. This work concerns the controls of eight failed crept specimens submitted to XRD examinations. Eight XRD diagrams were produced and subsequently compared with 12 replicas for each specimen; that is, 96 extraction replicas were produced for this work. Then, around 5000 precipitates were analyzed for each specimen; therefore, for this work, around 40,000 precipitates were characterized with their chemical compositions. The average size of the precipitates was around 97 nm.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"5 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85159554","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":"Hydrofluoric Acid-Free Digestion of Organosilicon Nanoparticles for Bioanalysis by ICP-OES","authors":"Nooshin Yousefpour, O. Björnberg, I. Yao Mattisson, O. Axelsson","doi":"10.3390/micro3010019","DOIUrl":"https://doi.org/10.3390/micro3010019","url":null,"abstract":"A novel ICP-OES method has been developed for the determination of Si concentration, originating from polyorganophosphosilanes, in biological specimens that also contain metal ions. The method is free of hazardous hydrofluoric acid (HF) and involves digestion with HNO3/H2O2 prior to the analysis by ICP-OES. High and reproducible spike recovery was obtained from the controls.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"52 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73434982","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":"The Importance of Biofilms on Microplastic Particles in Their Sinking Behavior and the Transfer of Invasive Organisms between Ecosystems","authors":"C. Gaylarde, M. P. de Almeida, Charles V. Neves, José Antônio Baptista Neto, E. M. da Fonseca","doi":"10.3390/micro3010022","DOIUrl":"https://doi.org/10.3390/micro3010022","url":null,"abstract":"Although plastic is ubiquitous in marine systems, our current knowledge of its transport is limited. Recent studies suggest size-selective removal of small plastic particles (<5 mm) from the ocean surface as a result of the formation of a biofilm (the “plastisphere”) on the microplastic particle (MP) surface. This localized microenvironment can isolate the microcosm from the adjacent aqueous medium, and thus protect component alien species from the surrounding physico-chemical conditions. Apart from resulting in specific conditions for the transfer of alien species through the environment, the plastisphere can impact MP hydrodynamics and cause MPs to move through the water column, initially sinking. The importance of this phenomenon has not been previously considered for these particles. The size-dependent vertical movement of MPs through the water column determines their distribution, which will vary with time of exposure and colonization. Some plastisphere organisms have plastic-degrading activities, which could be harnessed in marine depollution strategies. This article seeks to increase our understanding of the role of biofilms in the biological dynamics and diffusion of plastic microparticles.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"77 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90447985","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 CdSTe QDs’ Crystal Size on Viability and Cytochrome P450 Activity of CHO-K1 and HEP-G2 Cells","authors":"L. Alamo-Nole, Adriana Ponton-Almodovar, Ivan Ortiz-Laboy","doi":"10.3390/micro3010021","DOIUrl":"https://doi.org/10.3390/micro3010021","url":null,"abstract":"In the last few years, quantum dots (QDs) have attracted research interest in different fields of science and technology. Despite their applications, it is essential to understand how nanomaterials (with different crystal sizes) are metabolized inside organisms. Thus, the focus of this study was on an evaluation of how crystal sizes of CdSTe QDs affect the viability and response of the cytochrome P450 system in CHO-K1 and HEP-G2 cells. CdSTe QDs were synthesized using a microwave-assisted system at different reaction temperatures (60, 120, 150, and 180 °C) to obtain different crystal sizes. The optical and structural characterization confirmed four crystal sizes from 3 to 8 nm. Fluorescence microscopy confirmed that CdSTe QDs are incorporated into both cell lines. Viability studies suggested that CHO-K1 cells are more sensitive than HEP-G2 cells to CdSTe QDs and Cd+2 ions. The responsible mechanisms for the toxicity of QDs and Cd+2 are apoptosis followed by necrosis. The activity of CYP 1A1, 1A2, and 3A4 isoenzymes suggests that the smallest CdSTe crystals are recognized in a manner similar to that of Cd+2. Furthermore, the largest CdSTe crystals can have different metabolic routes than Cd+2.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"16 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90847699","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":"Structural Consequences of Post-Synthetic Modification of Cu2P3I2","authors":"Gregory R. Schwenk, John T. Walters, H. Ji","doi":"10.3390/micro3010018","DOIUrl":"https://doi.org/10.3390/micro3010018","url":null,"abstract":"In an attempt to widen the family of Phosphorus Metal Halides (MxPyXz) and enable new applications, post-synthetic modifications to the MxPyXz, Cu2P3I2 have been reported. While such a technique suggests access to an entirely new family of MxPyXz-based materials, we report, in this work, that the ion-exchange process seemingly influences important properties such as the crystallographic pattern and vibrational modes.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"131 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82666670","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":"InGaAsSb/GaAsSb quantum dot structures","authors":"Mushtaq Obaid Oleiwi,&nbsp;Baqer O. Al-Nashy,&nbsp;Sadeq Kh. Ajeel,&nbsp;Amin H. Al-Khursan","doi":"10.1049/mna2.12159","DOIUrl":"https://doi.org/10.1049/mna2.12159","url":null,"abstract":"&lt;p&gt;This work studies the modal gain from &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;I&lt;/mi&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;n&lt;/mi&gt;\u0000 &lt;mi&gt;x&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;mi&gt;G&lt;/mi&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;a&lt;/mi&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;mi&gt;x&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;mi&gt;A&lt;/mi&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;s&lt;/mi&gt;\u0000 &lt;mi&gt;y&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;mi&gt;S&lt;/mi&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;b&lt;/mi&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;mi&gt;y&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msub&gt;\u0000 &lt;mo&gt;/&lt;/mo&gt;\u0000 &lt;mi&gt;G&lt;/mi&gt;\u0000 &lt;mi&gt;a&lt;/mi&gt;\u0000 &lt;mi&gt;A&lt;/mi&gt;\u0000 &lt;mi&gt;s&lt;/mi&gt;\u0000 &lt;mi&gt;S&lt;/mi&gt;\u0000 &lt;mi&gt;b&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$I{n_x}G{a_{1 - x}}A{s_y}S{b_{1 - y}}/GaAsSb$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; quaternary quantum dots (QD) structures at different mole fractions of the structure. The quaternary structures are more flexible in attaining lattice-matching systems. First, the In- and As-mole fractions are varied. Four In-mole fractions are studied &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 &lt;mi&gt;x&lt;/mi&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mo&gt;=&lt;/mo&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mn&gt;0.01&lt;/mn&gt;\u0000 &lt;mo&gt;,&lt;/mo&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mn&gt;0.03&lt;/mn&gt;\u0000 &lt;mo&gt;,&lt;/mo&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mn&gt;0.05&lt;/mn&gt;\u0000 &lt;mo&gt;,&lt;/mo&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$(x; = ;0.01,;0.03,;0.05,;$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and 0.07), and their emitted wavelengths cover the range &lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;571.4&lt;/mn&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;mn&gt;5000&lt;/mn&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mi&gt;nm&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$571.4 - 5000 {rm nm}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;. Both In- and the As-mole fraction increment results in a red-shifted wavelength. Doping is also investigated where the structures are exhibited five times increment of modal gain, and the wavelength is blue-shifted under doping. A multi-peak behaviour","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"18 2","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mna2.12159","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50140836","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":"Influence of the Chromium Content on the Characteristics of the Matrix, the Tantalum Carbides Population, and the Hardness of Cast Co(Cr)-0.4C-6Ta Alloys","authors":"P. Berthod, Merzouk Bouaraba, Junfu Cai","doi":"10.3390/micro3010017","DOIUrl":"https://doi.org/10.3390/micro3010017","url":null,"abstract":"The mechanical and chemical behaviors of cast cobalt-base superalloys are governed by the carbides and by a reactive element, which is often chromium. The content of this later element, which is efficient in resisting hot oxidation and also hot corrosion, may have consequences on the melting temperature, microstructure, and mechanical properties at high temperatures and at room temperature. Seemingly, the effect of chromium content on the microstructure and properties of cast equi-axed Co-Cr-Ta-C superalloys containing TaC as single reinforcing carbide and in high-enough quantities to achieve a high level of creep resistance has not been the subject of previous investigations. The present work is devoted to the exploration of this influence of Cr content on the as-cast microstructure of a model alloy in this category, as well as on its microstructure transformations at high temperatures. The work aims to help rate the Cr content to achieve the best characteristics in machinability and high-temperature properties. This is of great importance for fabricability (production cost) and sustainability in service (long enough lifetime performance). A series of six alloys derived from a rather well-known alloy and presenting various Cr contents were thus elaborated by casting. Their microstructures were investigated in their as-cast state as well as in an aged state resulting from a 4-day stage at 1400 K. Vickers indentation was also carried out to study how hardness may evolve with Cr content. It was seen that the higher the Cr content, the lower the solidus temperature, the coarser the TaC population, the harder the alloy, and the higher the risk of brittleness. In order to reach the best compromise, the preferred Cr weight content range, as identified by this work, is 20–30%; indeed, for such Cr contents: (1) the matrix is austenitic, then dense, and then hard and not brittle, and thus is mechanically resistant and tough; (2) the TaC carbides are script-shaped and resistant against morphology changes at high temperatures, and thus efficiently preserve interdendritic cohesion for a long time, and, consequently, (3) the alloys are machinable, have expected good toughness, and can be resistant against creep deformation as well as oxidation and corrosion at high temperatures thanks to the Cr content, allowing for chromium-forming behavior.","PeriodicalId":18398,"journal":{"name":"Micro & Nano Letters","volume":"59 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77249497","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}