Field Of Nano Research Articles

Advanced technologies for the development of infectious disease vaccines.

Vaccines play a critical role in the prevention of life-threatening infectious disease. However, the development of effective vaccines against many immune-evading pathogens such as HIV has proven challenging, and existing vaccines against some diseases such as tuberculosis and malaria have limited efficacy. The historically slow rate of vaccine development and limited pan-variant immune responses also limit existing vaccine utility against rapidly emerging and mutating pathogens such as influenza and SARS-CoV-2. Additionally, reactogenic effects can contribute to vaccine hesitancy, further undermining the ability of vaccination campaigns to generate herd immunity. These limitations are fuellingthe development of novel vaccine technologies to more effectively combat infectious diseases. Towards this end, advances in vaccine delivery systems, adjuvants, antigens and other technologies are paving the way for the next generation of vaccines. This Review focuses on recent advances in synthetic vaccine systems and their associated challenges, highlighting innovation in the field of nano- and nucleic acid-based vaccines.

Surface Modification of Gold Nanorods: Multifunctional Strategies and Application Prospects.

Gold nanorods (AuNRs), as an important type of gold nanomaterials, have attracted much attention in the nano field. Compared with gold nanoparticls, AuNRs have broader application potential due to their tunable localized surface plasmon resonance properties and anisotropic shapes. Yet, conventional synthesis methods using surfactants have limited the use of AuNRs in a variety of fields such as biomedical applications, plasma-enhanced fluorescence, optics and optoelectronic devices. To solve this problem and improve the stability and biocompatibility of AuNRs, researchers in recent years have used surface modification and functionalization to modify AuNRs, among which the introduction of organic ligands to prepare organic/gold hybrid nanorods has become an effective strategy. Organic materials have better toughness and easy processing, and by introducing organic ligands into the surface of AuNRs, the molecular-level composite of organic and inorganic materials can be realized, thus obtaining hybrid nanorods with excellent properties. This paper reviews the research progress of hybrid nanocomposites, and introduces the synthesis methods of AuNRs and the development of surface ligand modification, then summaries the applications of a wide variety of ligands. Also, the advantages and disadvantages of different ligands and their roles in further self-assembly processes are discussed.

Kretschmann configuration as a method to enhance optical absorption in two-dimensional graphene-like semiconductors

Objectives. The optical properties of two-dimensional semiconductor materials, specifically monolayered transition metal dichalcogenides, present new horizons in the field of nano- and optoelectronics. However, their practical application is hindered by the issue of low light absorption. When working with such thin structures, it is essential to consider numerous complex factors, such as resonance and plasmonic effects which can influence absorption efficiency. The aim of this study is the optimization of light absorption in a two-dimensional semiconductor in the Kretschmann configuration for future use in optoelectronic devices, considering the aforementioned phenomena. Methods. A numerical modeling method was applied using the finite element method for solving Maxwell’s equations. A parametric analysis was conducted focusing on three parameters: angle of light incidence, metallic layer thickness, and semiconductor layer thickness.Results. Parameters were identified at which the maximum area of absorption peak was observed, including the metallic layer thickness and angle of light incidence. Based on the resulting graphs, optimal parameters were determined, in order to achieve the highest absorption percentages in the two-dimensional semiconductor film.Conclusions. Based on numerical studies, it can be asserted that the optimal parameters for maximum absorption in the monolayer film are: Ag thickness <20 nm and angle of light incidence between 55° and 85°. The maximum absorption in the two-dimensional film was found only to account for a portion of the total absorption of the entire structure. Thus, a customized approach to parameter selection is necessary, in order to achieve maximum efficiency in certain optoelectronic applications.

Vibration of embedded restrained composite tube shafts with nonlocal and strain gradient effects

Torsional vibration response of a circular nanoshaft, which is restrained by the means of elastic springs at both ends, is a matter of great concern in the field of nano-/micromechanics. Hence, the complexities arising from the deformable boundary conditions present a formidable obstacle to the attainment of closed-form solutions. In this study, a general method is presented to calculate the torsional vibration frequencies of functionally graded porous tube nanoshafts under both deformable and rigid boundary conditions. Classical continuum theory, upgraded with nonlocal strain gradient elasticity theory, is employed to reformulate the partial differential equation of the nanoshaft. First, torsional vibration equation based on the nonlocal strain gradient theory is derived for functionally graded porous nanoshaft embedded in an elastic media via Hamilton’s principle. The ordinary differential equation is found by discretizing the partial differential equation with the separation of variables method. Then, Fourier sine series is used as the rotation function. The necessary Stokes' transformation is applied to establish the general eigenvalue problem including the different parameters. For the first time in the literature, a solution that can analyze the torsional vibration frequencies of functionally graded porous tube shafts embedded in an elastic media under general (elastic and rigid) boundary conditions on the basis of nonlocal strain gradient theory is presented in this study. The results obtained show that while the increase in the material length scale parameter, elastic media and spring stiffnesses increase the frequencies of nanoshafts, the increase in the nonlocal parameter and functionally grading index values decreases the frequencies of nanoshafts. The detailed effects of these parameters are discussed in the article.

Near-infrared Spectrum Characteristics of Micro-Nano Material Based Diffraction Optical Devices

Diffractive optics devices are optical devices in which the amplitude or phase of the incident light is spatially modulated periodically by a micro-nanomaterial based structure. The study of diffractive optics devices in the field of micro and nano can change the spectroscopic behavior of micro and nano diffractive optics devices by varying the microstructure of the structure and the optical wave properties, which can effectively and reasonably modulate the optical wave signal. To study the effect of different parameter structures on the performance of micro-nano diffraction optical devices, in this paper, two three-dimensional array structures of diffractive optical devices are proposed, which are a vertex-intersecting regular tetrahedron structure and a base-intersecting regular frustum structure. Using the Finite-Difference Time-Domain method, the spectroscopic images of the diffractive optics of the constructed micro-nano diffractive devices are studied in the near-infrared band by varying the height of the constructed structures, the type of structures, the wavelength of the incident light waves, and the polarization direction of the light waves in different 3D height coordinates. The effects of different parameter changes on the performance of the micro-nano diffractive optics devices were analyzed by image comparison. The results show that the best diffraction effect is achieved at a structure height of 0.9 μm for both models with different structure types. The study of both structures at this structure height reveals that the location of diffraction occurrence and the intensity of diffraction can be tuned by varying the structure and the relevant parameters such as the polarization of the light wave. This paper has some theoretical applications for the study of high-performance diffractive optics.

Controlled synthesis of nanoparticles of high-etropy materials. Optimization of traditional and creation of innovation strategies

In the last decade, the diversity of high-entropy materials (HEMs) has increased sharply, including due to the expansion of research into the field of amorphous, nano- and heterostructures. Interest in nanoscale HEMs is primarily associated with their potential application in various fields, such as renewable and green energy, catalysis, hydrogen storage, surface protection and others. The development of nanotechnology has made it possible to develop an innovative design of nanoscale HEMs with fundamentally new structures with unique physical and chemical properties. Problems of controlled synthesis with precisely specified parameters of chemical composition, microstructure and morphology are solved. At the same time, traditional technologies such as fast pyrolysis, mechanical alloying, magnetron sputtering, electrochemical synthesis, etc. are being modernized. Along with this, innovative synthesis technologies have appeared, such as carbothermic shock, the method of controlled hydrogen spillover. The review discusses various methods for the synthesis of nanoscale HEMs that have been developed in the last few 6–7 years for various applications. Some of them are modernization of traditional methods for producing HEM or nano-sized materials, while another group of techniques represents innovative solutions stimulated and inspired by the HEM phenomenon.

Graphene & its applications as field effect transistors

Graphene, owing to its excellent physical, mechanical, and electrical properties, as well as its outstanding optoelectronic properties, has garnered significant attention. Consequently, it has opened numerous opportunities for various types of future devices and systems. Graphene, a one-atom-thick layer of carbon atoms forming a honeycomb 2D crystal lattice, stands out as one of the most promising candidates in the field of nano- and microelectronics. This review provides an introduction to graphene, detailing its properties and its applications, particularly focusing on its utilization in the realm of Field Effect Transistors (FETs). Specifically, an analytical device model of heterostructure-based FETs is presented, which essentially comprises an array of nano ribbons clad. The model for Graphene Nano Ribbon (GNR) FETs includes Poisson's equation and can be employed to calculate the current-voltage characteristics and spatial distribution of electric potential along the channel.

Bibliometric visual analysis of the poly(vinylidene fluoride–trifluoroethylene) piezoelectric nanomaterial: research history, hotspots, and developmental trend

Introduction: Poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] stands out as an organic polymer with remarkable piezoelectric properties, coupled with high chemically stability and biocompatibility, rendering it the most promising organic piezoelectric nanomaterial. Therefore, we aim to explore its developmental history, find current research hotspots, and identify emerging trends.Methods: To comprehensively review the pertinent literature on poly(vinylidene fluoride-trifluoroethylene) or P(VDF-TrFE) in English from 1992 to 2022, we utilized the Web of Science Core Collection. Additionally, bibliometric tools such as CiteSpace, VOSviewer, Bibliometrics online analysis platforms (https://bibliometric.com), along with SCImage graphics, were employed to delineate historical features, track the evolution of active topics, and identify emerging trends on the P(VDF-TrFE) field.Results: The annual publication and citation counts for articles on P(VDF-TrFE) have exhibited consistent growth since 1992, with Asia, notably China, contributing the highest number of publications on P(VDF-TrFE) materials. Interestingly, researchers in the United States demonstrated the most robust international collaborations across various countries. Keywords were categorized into nine clusters: 0# vinylidene fluoride, 1# thin-film transient, 2# energy harvesting, 3# dielectric property, 4# thin film, 5# film, 6# mobile modeling, 7# growth, and 8# pyroelectric sensor. The performance of constituent materials in electronic energy-storage applications and current and future research in nanofields, including nanofilms, nanofibers, and nanogenerator, are considered hotspots and developmental trends, respectively. Among the most cited articles, these articles are commonly related to PVDF and P(VDF-TrFE) ferroelectricity.Conclusion: Therefore, we believe that the electromechanical coupling performance of P(VDF-TrFE) and the research in nano fields is research hotspot that will trend into the future.

Redistribution of hydrophobic hypericin from nanoporous particles of SBA-15 silica in vitro, in cells and in vivo

Nanoporous silica is nowadays used in various fields of nano- and micro-materials research. The advantage of nanoporous material is that it can be filled with various hydrophilic and hydrophobic molecules, which are then delivered to the target cells and tissues. In the present study, we have studied the interaction of nanoporous silica with hydrophobic and photodynamically active molecule - hypericin. Hypericin was adsorbed on/in SBA-15 silica, which led to the disappearance of its fluorescence due to hypericin aggregate formation. However, it was observed here that hypericin can be easily redistributed from these particles towards proteins and lipids in serum and cells in vitro and in vivo. Moreover, the charged surface character of SBA-15 pores forced the creation of protein/lipid corona on particles. Such complex enabled monomerization of hypericin on the surface of particles presented by fluorescence in the corona and singlet oxygen production suitable for photodynamic therapy (PDT). The PDT efficacy achieved by introducing the new construct into the PDT protocol was comparable to the efficacy of hypericin PDT. In conclusion, this study demonstrates a promising approach for the delivery of hydrophobic photosensitizers to cancer cells by nanoporous silica using fluorescence techniques.

Design and investigation of extended source F-type nano field effect transistor using non-equilibrium Green's function

In this manuscript, a novel semiconductor device termed an extended source F-type nano field effect transistor is proposed. The low bandgap material used at the source electrode is extended up to the drain electrode. At the drain electrode, extended material is confined by wide bandgap material to reduce the OFF-State current. For simulation, Schrodinger-Poisson equations are used to construct the Hamiltonian and non-equilibrium Green's function is used to evaluate the transport. For a thorough analysis, various materials are considered at source and drain electrodes. After investigation, the device is proposed with Si0.45Ge0.55 at the source electrode and SiC as confining material. The proposed device resulted in IOFF = 3.6 × 10−14 A/μm and ION = 8.27 × 10−4 A/μm. IDS-VGS characteristics are justified on basis of energy curve, transmission probability, and density of states at source and drain terminal. For the entire combination, device resulted in a subthreshold slope of approximately 60mV/dec. The proposed device can be used in the future to replace current field-effect transistors as it results in better characteristics than metal oxide semiconductor field effect transistors and will have a much simpler fabrication process than tunnel field-effect transistors.

The computational study of initial temperature/pressure and atomic doping effects on the growth of crack in graphene nanostructure: Molecular dynamics approach

Graphene is a two-dimensional material with excellent mechanical, electrical, and thermal properties made up of single layers of carbon atoms. Despite the fact that graphene is an emerging material, nowadays graphene has become the leader of the nano field, and with the discovery of its various properties, a tremendous transformation is taking place in nano science. In this study, the molecular dynamics method was used to examine the mechanical characteristics of graphene nanosheets. To achieve this, zig-zag and armchair-shaped graphene nanosheet samples were first simulated. In the second step of this research, by adding boron and nitrogen impurities inside the nanosheet structure, the growth of cracks in these structures was studied, and the effect of factors, such as temperature, pressure, and adding impurity atoms, such as nitrogen and boron were evaluated. In graphene nanosheets with zig-zag and armchair structures, the results demonstrate that the greatest fracture lengths were 28.91 Å and 23.6 Å, respectively. The crack length increased from 23.60 Å to 30.68 Å by increasing the temperature from 300 to 400 K. From 0 bar to 1 bar of pressure, the crack length went from 23.60 Å to 29.01 Å. The type of plates affected the mechanical properties in nanosheets, and nanosheets with armchair edges had better mechanical properties. Finally, the effect of impurities on graphene nanosheets was investigated. The simulations showed improved mechanical properties and resistance to crack growth in the presence of boron, nitrogen, or a combination of these atoms.

Angular orientation between the cores of iron oxide nanoclusters controls their magneto–optical properties and magnetic heating functions

Oriented attachment of nanobricks into hierarchical multi-scale structures such as inorganic nanoclusters is one of the crystallization mechanisms that has revolutionized the field of nano and materials science. Herein, we show that the mosaicity, which measures the misalignment of crystal plane orientation between the nanobricks, governs their magneto-optical properties as well as the magnetic heating functions of iron oxide nanoclusters. Thanks to high-temperature and time-resolved millifluidic, we were able to isolate and characterize (structure, properties, function) the different intermediates involved in the diverse steps of the nanocluster’s formation, to propose a detailed dynamical mechanism of their formation and establish a clear correlation between changes in mosaicity at the nanoscale and their resulting physical properties. Finally, we demonstrate that their magneto-optical properties can be described using simple molecular theories.

Cross-scale and cross-precision structures/systems fabricated by high-efficiency and low-cost hybrid 3D printing technology

Three-dimensional (3D) printing is widely used in many fields such as micro-optics, microbiology, and microfluidics. However, using existing technologies is a challenge to efficiently fabricate high-quality 3D structures with cross-scale and cross-precision. In this paper, we propose a low-cost hybrid processing technology that combines two-photon polymerization (TPP) and DMD micro stereolithography (DMDMSL) (TPP-DMDMSL). This low-cost hybrid processing technology is a two-part alignment achieved by combining marker positioning and image processing, and then by coordinating the transformation of processing data. Using the same mark as a bridge, the two independent technologies are linked to realize hybrid processing. The high synergetic combination of the two technologies is realized by using the mask as the benchmark and combining it with the flexible real-time transformation of processing data. The horizontal and vertical alignment accuracy is 2 µm and 3 µm, respectively. TPP-DMDMSL unites the high precision of TPP with the high efficiency of DMDMSL. Taking the aspheric lens as an example (radius = 163 µm, height = 33 µm), TPP-DMDMSL reduces the time from 4 h to 1 h. The maximum surface error is 0.22 µm, which does not affect the image quality according to the Rayleigh criterion. TPP-DMDMSL manufactures different types of structures. These results prove that TPP-DMDMSL can print multiple types of 3D structures across scales and precision, which is challenging or time-consuming with existing technologies. TPP-DMDMSL will likely be extended to more micro and nano fields based on the original general technology. TPP-DMDMSL provides strong basic techniques and ideas for integrated hybrid processing systems in the future.

Metal–insulator–metal waveguide structure coupled with T-type and ring resonators for independent and tunable multiple Fano resonance and refractive index sensing

This study proposes a metal–insulator–metal (MIM) waveguide structure coupled with symmetric T-type resonators for exciting double Fano resonances. Furthermore, the proposed structure can generate an additional independent Fano resonance mode when one of the T-type resonators is replaced with a ring resonator. We employed the finite difference time domain method to simulate the transmission spectrum of the structure and the electric field distribution at resonant wavelengths. The formation mechanism of the Fano resonance is explained using the standing wave theory and multimode interference coupled mode theory. After studying the sensing characteristics of the designed structure, we achieved a maximum sensitivity of 1012 nm/RIU and a figure of merit of 5.57 × 104, which is higher than that of most of the structures reported recently. The proposed structure has broad application prospects in the field of nano sensing.

Biorobotics: An Overview of Recent Innovations in Artificial Muscles

In this overview of recent developments in the field of biorobotics we cover the developments in materials such as the use of polyester fabric being used as artificial skin and the start of whole new ways to actuate artificial muscles as a whole. In this, we discuss all of the relevant innovations from the fields of nano and microtechnology, as well as in the field of soft robotics to summarize what has been over the last 4 years and what could be improved for artificial muscles in the future. The goal of this paper will be to gain a better understanding of where the current field of biorobotics is at and what its current trends in manufacturing and its techniques are within the last several years.

Multimode Fano Resonances Sensing Based on a Non-Through MIM Waveguide with a Square Split-Ring Resonance Cavity.

In this article, a non-through metal–insulator–metal (MIM) waveguide that can excite fivefold Fano resonances is reported. The Fano resonances are obtained by the interaction between the modes excited by the square split-ring resonator (SSRC) and the bus waveguide. After a detailed analysis of the transmission characteristics and magnetic field strength of the structure using the finite element method (FEM), it was found that the independent tuning of Fano resonance wavelength and transmittance can be achieved by adjusting the geometric parameters of SSRC. In addition, after optimizing the geometric parameters, the refractive index sensing sensitivity (S) and figure of merit (FOM) of the structure can be optimal, which are 1290.2 nm/RIU and 3.6 × 104, respectively. Additionally, the annular cavity of the MIM waveguide structure can also be filled with biomass solution to act as a biosensor. On this basis, the structure can be produced for optical refractive index sensing in the biological, micro and nano fields.

Tunability of resonator with pre-compressed springs on thermo-magneto-mechanical coupling band gaps of locally resonant phononic crystal nanobeam with surface effects

A locally resonant (LR) thermo-magneto-mechanical phononic crystal (PC) nanobeam by periodically attaching “vertical spring-precompressed spring-mass” resonators onto the surface of base nanobeam is proposed, which the corresponding band structure is calculated by extending surface elasticity theory and thermo-magneto-mechanical coupling constitutive model to plane wave expansion (PWE) method. In addition, the influencing rules of resonator, thermo-magneto-mechanical fields, surface effects and geometric parameters are discussed. Numerical results and further analysis demonstrate that more band gaps with lower starting frequency and wider frequency range can be opened by periodically adding resonators onto the surface of nanobeam. The horizontal springs with larger degree of pre-compression can obtain lower starting frequency of first band gap. The effect of operating temperature on band gaps can be regarded as the relation between operating temperature and Young’s modulus of epoxy. Moreover, a singular pre-stress is existed that makes the band gaps not easily opened, which keeps increasing by increasing operating temperature, magnetic field, the ratio between width and thickness or decreasing the ratio between lengths of Terfenol-D and epoxy. All the researches are expected to be applied to the active control of vibration propagation in the field of nano thermo-magneto-mechanical system.

Current Advances of Polysaccharide-Based Nanogels and Microgels in Food and Biomedical Sciences.

Polysaccharides are natural polymers with hydrophilic, biocompatible and biodegradable characteristics and have many opportunities in the food and pharmaceutical sectors. This review focuses on the field of nano and microstructures whose internal structure is based on networked polysaccharide chains in 3D i.e., polysaccharide nanogels (NGs) and microgels (MGs). As it is observed the number of articles on NGs and MGs in peer reviewed scientific journals has been increasing over the last two decades. At the same time, the relative contribution of polysaccharides in this field is gaining place. This review focuses on the different applied methods for the fabrication of a variety of polysaccharide-based NGs and MGs and aims to highlight the recent advances on the subject and present their potentials and properties with regards to their integration in aspects of medicinal and food sciences. The presentation of the recent advances in the application of polysaccharide NGs and MGs is divided in materials with potential as emulsion stabilizers and materials with potential as carriers of bioactives. For applications in the medical sector the division is based on the fabrication processes and includes self-assembled, electrostatically complexed/ionically crosslinked and chemically crosslinked NGs and MGs. It is concluded that many advances are expected in the application of these polysaccharide-based materials and in particular as nutrient-loaded emulsion stabilizers, viscosity modifiers and co-assembled structures in combination with proteins.

Trends in hyperspectral imaging: from environmental and health sensing to structure-property and nano-bio interaction studies.

Hyperspectral imaging (HSI) is a technique that allows for the simultaneous acquisition of both spatial and spectral information. While HSI has been known for years in the field of remote sensing, for instance in geology, cultural heritage, or food industries, it recently emerged in the fields of nano- and micromaterials as well as bioimaging and -sensing. Herein, the attractiveness of HSI arises from the suitability for generating knowledge about environment-specific optical properties, such as photoluminescence of optical probes in a biological sample or at a single-crystal/particle level, to be leveraged into better understanding of structure-property relationships and nano-bio interactions, respectively. Moreover, given its excellent spectral resolution, HSI is highly suitable for optical multiplexing in multiple dimensions, as sought after for, e.g., high throughput biological imaging by simultaneous tracking of multiple targets. Overall, HSI is an emerging technique that has the potential to transform analytical approaches from biomedicine to advanced materials research. This Trends Article provides insight into the potential of HSI, highlighting selected examples from well-established fields including environmental monitoring and food quality control to set the stage for the discussion of emerging opportunities at the micro- and nanoscale. Herein, special focus is set on photoluminescent micro- and nanoprobes for health and spectral conversion applications.

New progress in international nanotechnology research in the past ten years – visual analysis based on CitesSpace

With the continuous development of high-tech industry, Moore’s law is close to the limit. People urgently need nano science and technology to trigger a new scientific and technological revolution to meet the needs of life, military and so on. Nanotechnology covers almost all industries and has made achievements in the industries such as medical, materials, manufacturing, and information technology. It has changed the production and life of human beings and subverted many industries. In recent years, more and more people have conducted data mining on nanotechnology research. By combing the literature, this paper summarizes the core authors, keyword changes, important authors and emergent words of the existing literature. Contributing to analyzing the research status of this field and revealing research hotspots in this field. It is of great significance for scholars to sort out the development process of nano field and predict the future development trend. Using CitesSpace bibliometric analysis software, 44002 pieces of literature about nanotechnology in SCI and SSCI journals in the core collection of the Web of Science database were analyzed in this paper. The results indicated that countries such as the United States, Germany, China, and Japan have issued more articles; However, the centrality of articles published in European countries such as the UK, Germany, and France was relatively strong; High-yield units mainly included Chinese Acad Sci and Russian Acad Sci; The main research scholars were Wei Wang, Peixuan Guo, Thomas J Webster, Hao Yan; Research emergent words primarily included polymer, particle, dynamics, mechanical properties and silver nanoparticle. On this basis, countermeasure suggestions and prospects are proposed.