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1.
Bio/artificial hybrid nanosystems based on biological matter and synthetic nanoparticles (NPs) remain a holy grail of materials science. Herein, inspired by the well-defined metal–organic framework (MOF) with diverse chemical diversities, the concept of “armored red blood cells” (armored RBCs) is introduced, which are native RBCs assembled within and protected by a functional exoskeleton of interlinked MOF NPs. Exoskeletons are generated within seconds through MOF NP interlocking based on metal-phenolic coordination and RBC membrane/NP complexation via hydrogen-bonding interactions at the cellular interface. Armored RBC formation is shown to be generalizable to many classes of MOF NPs or any NPs that can be coated by MOF. Moreover, it is found that armored RBCs preserve the original properties of RBCs (such as oxygen carrier capability and good ex ovo/in vivo circulation property) and show enhanced resistance against external stressors (like osmotic pressure, detergent, toxic NPs, and freezing conditions). By modifying the physicochemical properties of MOF NPs, armored RBCs provide the capability for blood nitric oxide sensing or multimodal imaging. The synthesis of armored RBCs is straightforward, reliable, and reversible and hence, represent a new class of hybrid biomaterials with a broad range of functionalities.  相似文献   

2.
Windows play significant roles in commercial and residential buildings and automobiles, which direct and control light illumination, thermal insulation, natural ventilation, and aesthetics. Various approaches are attempted to make windows “smart” by tailoring their transparency and thermal insulation in response to environmental changes. Hence, there has been much effort to develop smart windows that can dynamically modulate the transmission and reflectance of the visible light and solar radiance into buildings according to weather conditions or personal preferences. Development of smart window materials is also beneficial to applications including wearable sensors, energy harvesting and storage, and medical devices. By carefully matching the refractive indices of nanoparticle (NPs) and polymer matrix, surface chemistry, and their mechanical properties, particle‐embedded polymer composites can exhibit synergistic effects with improved chemical and mechanical stability, enhanced dispersion of NPs, and optimized and stimuli‐responsive optical properties. Here, an overview of recent progresses in the development of smart windows based on electro‐, thermo‐, and mechanoactuations is provided. Additional functionalities, e.g., flexibility, stretchability, and mechanical/chemical stability, can also be achieved by careful choices of NPs and polymers.  相似文献   

3.
This review article summarizes recent progress in the fabrication methodologies and functional modulations of nanoparticle (NP)–polymer composites. On the basis of the techniques of NP synthesis and surface modification, the fabrication methods of nanocomposites are highlighted; these include surface‐initiated polymerization on NPs, in situ formation of NPs in polymer media, and the incorporation through covalent linkages and supramolecular assemblies. In these examples, polymers are foremost hypothesized as inert hosts that stabilize and integrate the functionalities of NPs, thus improving the macroscopic performance of NPs. Furthermore, due to the unique physicochemical properties of polymers, polymer chains are also dynamic under heating, swelling, and stretching. This creates an opportunity for modulating NP functionalities within the preformed nanocomposites, which will undoubtedly promote the developments of optoelectronic devices, optical materials, and intelligent materials.  相似文献   

4.
随着人类社会的发展,各种各样的媒体技术被广泛应用在生活、生产、军事等领域。在教学上,许多媒体正在发挥着越来越重要的作用,不断地将更多“新”的传播媒体引入教学应用,为教育传播的发展提供了巨大的机遇。“新媒体新技术”是一个相对的概念,新媒体新技术是建立计算机网络、数字化基础上的,为人民生活提供的不仅仅是新闻信息,更重要是在各个领域都发挥了举足轻重的作用,深受民众喜欢。  相似文献   

5.
The discovery of new lanthanide properties in layered rare‐earth hydroxides is tremendously important to developing novel materials with the advantages of both lanthanides and layered hydroxides. Herein, a polyethylenimine‐assisted hydrothermal route for preparing Ce‐doped layered yttrium hydroxide nanoplates (LYH:Ce NPs) is established, in which the Ce doping provides simultaneous control of the size and fluorescent properties. Typically, 10% Ce doping tailors the average particle size from 680 to 196 nm and induces bright blue luminescence with a quantum efficiency of over 10.0%. Owing to the much more efficient f–d Ce3+ transition, the LYH:Ce NPs show three orders of magnitude stronger photoluminescence than LYH:Eu and LYH:Tb NPs, and exhibit the properties required to fabricate switched “on/off” optical sensors by controlling the Ce3+ ? Ce4+ redox couple. Furthermore, by combining the merits of the luminescence of Ce3+ dopants and anion‐exchange ability of an LYH host, the LYH:Ce NPs exhibit the properties necessary for photofunctional materials for photosensitized singlet oxygen production.  相似文献   

6.
Electrets are normally applied for energy conversion from mechanical vibration sources in the environment to electrical power without any friction, which induces electric device sustainability and mechanically robust. It functions for electron storage and electrostatic/triboelectric effect, whose electrical/mechanical performance dramatically benefits energy harvesters, self-powered sensors, and even intelligent/sustainable systems. To summarize the progress of electret-based electronics, this review proposes three key issues around enhanced energy harvesting toward sensors and sustainable systems. First, with the properties of long-term charge storage characteristics and the contactless mechanism for energy harvesting, the enhancement effect in electret from MEMS devices, porous microstructure devices, and multilayer electret devices are carefully assessed with the output power from various devices. Second, the multi-functional applications aspect along with the triboelectric coupling effect and artificial piezoelectric materials are discussed as future electret devices, for example, polydimethylsiloxane materials. Third, more than energy harvesting, machine learning-enabled methodology in electret electronics can be more reliable and sustainable, dramatically contributing to the living standard of the society. Electret technologies on the future development trends are finally analyzed and strengthened toward multifunctional, sustainable, and intelligent systems along with the upcoming technologies in coupling mechanism, artificial composite materials, and machine learning in data fusion.  相似文献   

7.
High entropy materials made up of dissimilar elements have enormous potentials in various fields and applications such as catalysis, energy generation and bioengineering. Developments of facile rapid synthesis routes toward functional multicomponent nanoparticles (NPs) of metals and ceramics with control of single/mixed crystalline structure configurations as well as understanding their transformative behaviors to enable unexpected properties, however, has remained challenging. Here a transient laser heating strategy to generate high entropy metal alloy, oxide, and nitride nanoparticles (HE-A/O/N NPs) is described. Laser irradiation of the identical metal salt mixture under different millisecond heating times provides direct control of cooling rates and thereby results in HEA NPs with tunable single- and multiphasic solid solution characteristics, atomic compositions, nanoparticle morphologies, and physicochemical properties. Extending the elemental selection to nitride-forming precursors enables laser-induced carbothermal reduction and nitridation of high entropy tetragonal rutile oxide nanoparticlesNPs to the cubic rock salt nitride phase. The combination of laser heating with spatially resolved X-ray diffraction facilitates combinatorial studies of phase transitions and reaction pathways of multicomponent nanoparticles. These findings provide a general strategy to design nonequilibrium multicomponent metal alloys and ceramic materials amalgamations for fundamental studies and practical applications such as carbon nanotube growth, water splitting, and antimicrobial applications.  相似文献   

8.
This article addresses whether the discipline of communication can contribute answers to the question what a “good life” could be, particularly regarding recent developments in new communication technologies. It starts with the assumption that much of human striving results from 3 fundamental needs that new technologies promise to satisfy as they allow us to be online and connected with others almost all the time. It posits that new ways of using electronic media do both, satisfying and challenging human needs at the same time. It suggests that communication scholars should also focus on pressing societal problems, such as understanding the competent handling of these new technologies. Ultimately, it proposes to intensify our attempts to work more interdisciplinarily and more internationally.  相似文献   

9.
Slippery omniphobic covalently attached liquids enable smooth, transparent, pressure- and temperature-resistant, and liquid-repellent coatings. Patterned functionalization of such surfaces would drive technology developments and fundamental understandings in broad applications from biosensors to sustainable smart surfaces. Herein an additive microcontact printing approach in combination with the microdroplet-confined synthesis is developed to functionalize slippery surfaces tethered with “liquid-like” linear poly(dimethylsiloxane) by multifunctional polydopamine (PDA) arrays. Using glycerol and non-ionic surfactant Tween-20, microdroplet arrays containing dopamine monomers are printed onto the slippery surfaces and serve as microreactors for the in situ growth of PDA micropatterns. The confined growth approach enables tunable feature size, height, and morphology of the patterns, through which sub-micrometer PDA dot arrays over centimeter-square patterning area can be reliably achieved. Furthermore, the reactive and hydrophilic PDA micropatches allow further functionalization of the slippery surfaces with a diverse variety of materials, meanwhile the anti-fouling and dynamically dewetting “liquid-like” brushes permit minimum background contamination. Proof-of-concept demonstrations include PDA-initiated photografting for stimuli-responsive polymer functionalization, protein immobilization for microarray-based immunoassays, as well as sliding-induced selective dewetting of organic solutions to pattern photoluminescent perovskite microcrystals and nanoparticles. The current approach illustrates the potential for applying patterned slippery surfaces with multifunctional architectures in many fields.  相似文献   

10.
Fog formation decreases light transmission of optically clear materials. A promising approach to address this problem is to control the wetting properties of the material at extremes states, which requires imparting micro and nano morphology features on the surface. However, such features may affect the optical properties of the surface. In this work, superhydrophobic and superhydrophilic surfaces, with different morphology characteristics ranging from nanoscale to hierarchical micro-nanoscale are fabricated and evaluated in order to investigate which wetting extreme and surface morphology is more suitable to preserve the light-transmitting properties and exhibit antifogging functionalities. The performance of the aforementioned surfaces is compared for the first time in two different testing modes: under intense fog flow and no surface cooling, and under no-flow and surface cooling, which enhances dew condensation on the surfaces. It is demonstrated that superhydrophilic surfaces with nanoscale morphology maintain their optical transmittance under fog flow for more than 20 min. This duration is one of the longest reported in the literature revealing the long-term antifogging functionality of the proposed surfaces. Finally, by tailoring the morphology and the surface wetting properties, an optically switching surface (initially “milky” which becomes “clear”) when exposed to humidity is demonstrated.  相似文献   

11.
The ability to trigger changes to material properties with external stimuli, so-called “smart” behavior, has enabled novel technologies for a wide range of healthcare applications. Response to small changes in temperature is particularly attractive, where material transformations may be triggered by contact with the human body. Thermoreversible gelators are materials where warming triggers reversible phase change from low viscosity polymer solution to a gel state. These systems can be generated by the exploitation of macromolecules with lower critical solution temperatures included in their architectures. The resultant materials are attractive for topical and mucosal drug delivery, as well as for injectables. In addition, the materials are attractive for tissue engineering and 3D printing. The fundamental science underpinning these systems is described, along with progress in each class of material and their applications. Significant opportunities exist in the fundamental understanding of how polymer chemistry and nanoscience describe the performance of these systems and guide the rational design of novel systems. Furthermore, barriers to translating technologies must be addressed, for example, rigorous toxicological evaluation is rarely conducted. As such, applications remain tied to narrow fields, and advancements will be made where the existing knowledge in these areas may be applied to novel problems of science.  相似文献   

12.
Nanocomposites of metal nanoparticles (NPs) and bacterial nanocellulose (BC) enable fabrication of soft and biocompatible materials for optical, catalytic, electronic, and biomedical applications. Current BC–NP nanocomposites are typically prepared by in situ synthesis of the NPs or electrostatic adsorption of surface functionalized NPs, which limits possibilities to control and tune NP size, shape, concentration, and surface chemistry and influences the properties and performance of the materials. Here a self‐assembly strategy is described for fabrication of complex and well‐defined BC–NP composites using colloidal gold and silver NPs of different sizes, shapes, and concentrations. The self‐assembly process results in nanocomposites with distinct biophysical and optical properties. In addition to antibacterial materials and materials with excellent senor performance, materials with unique mechanoplasmonic properties are developed. The homogenous incorporation of plasmonic gold NPs in the BC enables extensive modulation of the optical properties by mechanical stimuli. Compression gives rise to near‐field coupling between adsorbed NPs, resulting in tunable spectral variations and enhanced broadband absorption that amplify both nonlinear optical and thermoplasmonic effects and enables novel biosensing strategies.  相似文献   

13.
Concave nanoparticles (NPs) with complex angled and non‐Platonic geometries have unique optical, magnetic, catalytic, and biological properties originating from the singularities of the electrical field in apexes and craters. Preparation of such particles with a uniform size/shape and core–shell morphology represents a significant challenge, largely because of the poor knowledge of their formation mechanism. Here, this challenge is addressed and a study of the mechanism of their formation is presented for a case of complex spiky morphologies that led us to the conclusion that NPs with concave geometries can be, in fact, supraparticles (SPs) produced via the self‐assembly of smaller convex integrants. This mechanism is exemplified by the vivid case of spiky SPs formed via the attachment of small and faceted Au NPs on smooth Au‐coated iron oxide (Fe3O4@Au) seeds. The theoretical calculations of energies of primary interactions—electrostatic repulsion and van‐der Waals repulsion, elaborated for this complex case—confirm experimental observation and the self‐limiting mechanism of SP formation. Besides demonstrating the mechanistic aspects of synthesis of NPs with complex geometries, this work also uncovers a facile approach for preparation of concave magnetoplasmonic particles. When combined with a spiky geometry, such bi‐functional magnetoplasmonic SPs can serve as a unique platform for optoelectronic devices and biomedical applications.  相似文献   

14.
Semiconducting polymer nanoparticles (SP NPs) are employed as efficient nanoagents for “all‐in‐one” theranostic nanoplatforms with dual photoacoustic imaging (PAI) and photothermal therapy (PTT) functions based on their photothermal conversion effect. However, the mechanisms of tuning the PTT efficiency are still elusive, though several SP NPs with high photothermal efficiency are reported. Herein, two donor–acceptor (D–A) SP NPs PTIGSVS and PIIGSVS with the same donor unit but different acceptor units are designed and synthesized. Through tuning the acceptor unit, PTIGSVS shows more planar backbone structure, stronger D–A strength, redshifted absorption, enhanced extinction efficient, weakened emission properties, and more efficient nonradiative decay in comparison to the polymeric analogue PIIGSVS . Thus, PTIGSVS NPs present much higher photothermal conversion efficiencies (74%) than PIIGSVS NPs (11%), resulting in significantly enhanced in vitro and in vivo PAI and PTT performance. This contribution demonstrates that PTIGSVS NPs are superior PA/PTT agents for effective cancer theranostic and shed light on understanding the relationship between molecular structures and photothermal effect of CPs.  相似文献   

15.
There is a constant drive for development of ultrahigh performance multifunctional construction materials by the modern engineering technologies. These materials have to exhibit enhanced durability and mechanical performance, and have to incorporate functionalities that satisfy multiple uses in order to be suitable for future emerging structural applications. There is a wide consensus in the research community that concrete, the most used construction material worldwide, has to be engineered at the nanoscale, where its chemical and physiomechanical properties can be truly enhanced. Here, an innovative multifunctional nanoengineered concrete showing an unprecedented range of enhanced properties when compared to standard concrete, is reported. These include an increase of up to 146% in the compressive and 79.5% in the flexural strength, whilst at the same time an enhanced electrical and thermal performance is found. A surprising decrease in water permeability by nearly 400% compared to normal concrete makes this novel composite material ideally suitable for constructions in areas subject to flooding. The unprecedented gamut of functionalities that are reported in this paper are produced by the addition of water‐stabilized graphene dispersions, an advancement in the emerging field of nanoengineered concrete which can be readily applied in a more sustainable construction industry.  相似文献   

16.
Flexible, material‐based, artificial muscles enable compliant and safe technologies for human–machine interaction devices and adaptive soft robots, yet there remain long‐term challenges in the development of artificial muscles capable of mimicking flexible, controllable, and multifunctional human activity. Inspired by human limb's activity strategy, combining muscles' adjustable stiffness and joints' origami folding, controllable stiffness origami “skeletons,” which are created by laminar jamming and origami folding of multiple layers of flexible sandpaper, are embedded into a common monofunctional vacuumed‐powered cube‐shaped (CUBE) artificial muscle, thereby enabling the monofunctional CUBE artificial muscle to achieve lightweight and multifunctionality as well as controllable force/motion output without sacrificing its volume and shape. Successful demonstrations of arms self‐assembly and cooperatively gripping different objects and a “caterpillar” robot climbing different pipes illustrate high operational redundancy and high‐force output through “building blocks” assembly of multifunctional CUBE artificial muscles. Controllable stiffness origami “skeletons” offer a facile and low‐cost strategy to fabricate lightweight and multifunctional artificial muscles for numerous potential applications such as wearable assistant devices, miniature surgical instruments, and soft robots.  相似文献   

17.
Wearable human‐interactive devices are advanced technologies that will improve the comfort, convenience, and security of humans, and have a wide range of applications from robotics to clinical health monitoring. In this study, a fully printed wearable human‐interactive device called a “smart bandage” is proposed as the first proof of concept. The device incorporates touch and temperature sensors to monitor health, a drug‐delivery system to improve health, and a wireless coil to detect touch. The sensors, microelectromechanical systems (MEMS) structure, and wireless coil are monolithically integrated onto flexible substrates. A smart bandage is demonstrated on a human arm. These types of wearable human‐interactive devices represent a promising platform not only for interactive devices, but also for flexible MEMS technology.  相似文献   

18.
With the emerging development of three-dimensional (3D) related technologies, 3D visual saliency modeling is becoming particularly important and challenging. This paper presents a new depth perception and visual comfort guided saliency computational model for stereoscopic 3D images. The prominent advantage of the proposed model is that we incorporate the influence of depth perception and visual comfort on 3D visual saliency computation. The proposed saliency model is composed of three components: 2D image saliency, depth saliency and visual comfort based saliency. In the model, color saliency, texture saliency and spatial compactness are computed respectively and fused to derive 2D image saliency. Global disparity contrast is considered to compute depth saliency. Particularly, we train a visual comfort prediction function to distinguish stereoscopic image pair as high comfortable stereo viewing (HCSV) or low comfortable stereo viewing (LCSV), and devise different computational rules to generate a visual comfort based saliency map. The final 3D saliency map is obtained by using a linear combination and enhanced by a “saliency-center bias” model. Experimental results show that the proposed 3D saliency model outperforms the state-of-the-art models on predicting human eye fixations and visual comfort assessment.  相似文献   

19.
《III》1996,9(5):51-57
MEMS are the manipulative little devices that have wormed their way to the top of the list of interesting “new” technologies this fall. When looking into the increasing number of MEMS initiatives, one conjectures that their popularity is because MEMS offer systems designers the opportunity to marry the “smaller, faster, smarter” philosophy with old fashioned facts of mechanical and human life.  相似文献   

20.
Our ambition here is to refine the various typologies that compose the mobility structure. We aim to complement the work done by Urry and investigate the role played in the structure of mobility by what we call the “network of personal technologies”. Our new model consists of four different levels: macro-mobilities, micro-mobilities, media mobility and disembodied mobilities. By “macro-mobilities,” we refer to the actions which imply consistent physical displacement, such as travels, tours and commuting. By “micro-mobilities,” we mean small-scale displacements, including bodily movements and emotions. With moving media, we refer both to the new mobility provided by the smartphone to the traditionally fixed media and to the penetration of these into public spaces. Finally, “disembodied mobility” designates the transformations that have taken place within the social order as earlier hierarchies of dimensions, values and meanings have been overturned. Hopefully, this new model will enable us to enhance the analysis of mobility structure by taking human beings and their bodies as a point of reference.  相似文献   

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