Interminable surveillance and reconnaissance through various sophisticated multispectral detectors present threats to military equipment and manpower. However, a combination of detectors operating in ...different wavelength bands (from hundreds of nanometers to centimeters) and based on different principles raises challenges to the conventional single-band camouflage devices. In this paper, multispectral camouflage is demonstrated for the visible, mid-infrared (MIR, 3-5 and 8-14 μm), lasers (1.55 and 10.6 μm) and microwave (8-12 GHz) bands with simultaneous efficient radiative cooling in the non-atmospheric window (5-8 μm). The device for multispectral camouflage consists of a ZnS/Ge multilayer for wavelength selective emission and a Cu-ITO-Cu metasurface for microwave absorption. In comparison with conventional broadband low emittance material (Cr), the IR camouflage performance of this device manifests 8.4/5.9 °C reduction of inner/surface temperature, and 53.4/13.0% IR signal decrease in mid/long wavelength IR bands, at 2500 W ∙ m
input power density. Furthermore, we reveal that the natural convection in the atmosphere can be enhanced by radiation in the non-atmospheric window, which increases the total cooling power from 136 W ∙ m
to 252 W ∙ m
at 150 °C surface temperature. This work may introduce the opportunities for multispectral manipulation, infrared signal processing, thermal management, and energy-efficient applications.
Thermal camouflage has attracted increasing attention owing to the rapid development of infrared (IR) surveillance technologies. Various materials and systems have been developed to date, but the ...realization of high‐temperature thermal camouflage using ultrathin film/coating remains a great challenge; this is of great significance, especially for IR stealth in military equipment. This work demonstrates a series of ultrathin Ti3C2Tx MXene films (as low as 1 µm) with superior high‐temperature indoor/outdoor thermal camouflage performance: wide camouflage temperature range (from below −10 °C to over 500 °C), large reduction in radiation temperature (exceeding 300 °C for objects with temperatures over 500 °C), long‐term high‐temperature or fire stability, multifunctionality including disguised Joule heating capability, and high electromagnetic interference shielding efficiency. The superior high‐temperature thermal camouflage performance of the ultrathin MXene film is attributed to its low mid‐IR emissivity (0.19), which is comparable to that of stainless steel but far below that of other 2D nanomaterials, such as graphene. The multifunctional ultrathin MXene films prepared through simple vacuum‐assisted filtration provide a feasible method for efficient high‐temperature thermal camouflage using ultrathin films, demonstrating the great promise of MXene materials for thermal camouflage, IR stealth, counter‐surveillance, and security protection.
This work provides a facile strategy for efficient high‐temperature thermal camouflage using ultrathin MXene films/coatings; the performance of the MXene films/coatings is almost comparable to that of stainless steel and superior to that of other 2D nanomaterials as well as other reported film‐/coating‐based thermal camouflage materials/systems. The results of this work demonstrate the great promise of MXene materials for thermal camouflage, infrared stealth, counter‐surveillance, and security protection.
Infrared stealth technology plays a vital role in development of defense industry and new military equipment. The current study focused on a novel type of flexible and foldable composite films based ...on polyimide (PI)/phosphorene (PR) hybrid aerogel and phase change material (PCM) for infrared stealth and thermal camouflage applications. The composite films were successfully obtained by fabricating a PI/PR hybrid aerogel through prepolymerizaton, film casting, freeze-drying, and thermal imidization, followed by vacuum impregnation of polyethylene glycol (PEG) as a PCM into the aerogel framework. The combination of PI and PR nanoflakes endows the hybrid aerogel with an effective enhancement in mechanical properties, near infrared absorption, and infrared photothermal conversion. The resultant composite films not only present prominent tensile and fatigue-resistant performance but also exhibit a good thermal regulation capability with a high latent-heat capacity of over 150 J/g. More importantly, the composite films demonstrate good infrared stealth and thermal camouflage performance on the high-temperature targets through effective thermal buffer and insulation. With ultralight, flexible, foldable, shape-tunable, and thermal self-regulatory characteristics, the PI/PR aerogel/PEG composite films developed by this work exhibit great application potential in infrared stealth and thermal camouflage for new military equipment.
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•A flexible and foldable composite film was designed for infrared stealth and thermal camouflage.•The film was based on the polyimide/phosphorene hybrid aerogel and phase change material.•The introduction of phosphorene enhances infrared absorption and photothermal conservation.•The film exhibit a good thermal regulation ability to buffer thermal swings.•The film shows great potential for stealth and camouflage applications in new military equipment.
The paper presents an analysis of the operational properties of paint coatings foruse in military technology in the field of masking. The assessment of the propertieswas performed on the basis of ...measurements of the surface geometric structureand adhesion using the peel method. The measurements of specular gloss, colourin the range of 400-700 nm and reflectance in the range of 350-1200 nm weremade in relation to the requirements of the Polish Defence Standard NO-80-A200.Coating systems are characterised by their low roughness and good adhesion. Dueto their operational properties, the developed coating systems can be used onarmaments and military equipment.
It is a challenge to manufacture self-healing material that possesses rapid, efficient and multichannel self-healing capability. Herein, we design and synthesize a polymer/graphene based self-healing ...material with a cross-linking network structure via Diels-Alder (D-A) reaction. The as-prepared material can be healed after damage under the stimuli of heat, infrared light, and microwave with controlling the formation and cleavage of D-A bonds. And it exhibits rapid (IR light-5 s, Heat/Microwave-60 s), efficient (efficiencies are 90% after heat-healed, 106% after IR-healed, and 133% after microwave-healed, respectively), and multichannel self-healing ability (i.e. can be self-healed in multiple ways). Furthermore, functionalized graphene oxide (FGO) has high grafting rate of 47.5% for GO-FA (graphene oxide (GO) was functionalized by Furfurylamine, FA), and 85.3% for GO-MDA (GO was functionalized by 6-Maleimidocaproic acid, MDA). In addition, photo-thermal conversion efficiency of the self-healing material was calculated with the average value reached up to 59.8%. The outstanding self-healing performances suggest that this self-healing material has huge promising potential applications in military equipment, protective coating and building materials, etc.
The polymer/graphene based self-healing material with a cross-linking network via Diels-Alder reaction is prepared. It can be self-healed through three ways of heating, microwave radiation, infrared light irradiation rapidly and efficiently along with high healing efficiencies of 90% after heat-healed for 60 s, 106% after IR-healed for only 5 s, and 133% after microwave-healed for 60 s through controlling the formation and cleavage of Diels-Alder bonds. Display omitted
Satellite remote sensing is undergoing a revolution in terms of sensors and temporal coverage. The possibility of acquiring earth's surface video from space provides an opportunity to investigate ...broader applications of remote sensing. High-resolution spaceborne videos can become a vital factor in earth observation. Temporally continuous tracking of moving objects, i.e. vehicles, vessels, or even military equipment on Earth's surface demands high spatial resolution satellite videos. Detecting moving vehicles in the urban areas from space video can lead governments to a new era of traffic monitoring. Satellite videos will find many applications in the field of traffic monitoring. In this article, first, moving vehicles are detected using background subtraction with 94.7% accuracy. Afterwards, vehicles' trajectories, average velocities, dynamic velocities, and space-time diagram are estimated and trajectories are classified based on velocities. Finally, the total frame traffic density is computed.
The national defence industry concentrates on military, electronic, information and space technologies. In the near future, Ukraine's defence industry may become one of the most knowledge-intensive ...industrial sectors of the economy. Accordingly, the purpose of the study is to assess the capacity of Ukrainian defence enterprises to produce weapons and military equipment to ensure national security. The research aims not only to assess the problems of the defence industry under martial law but also to ensure the effective development of the defence industry sectors by identifying priority areas of funding.It was found that the current state of the Ukrainian defence industry does not meet the current realities of the time, especially in the context of Russia's full-scale invasion of Ukraine. The provision of equipment and weapons to military units is at a low level. It is found that the renewal of modern models of weapons and military equipment of the Armed Forces of Ukraine, before the full-scale invasion, was less than 1%, which in turn did not allow to compensate for the rate of ageing of existing weapons. The authors suggest ways to support the development of Ukraine's defence industry, in particular, through the creation of a Defence Industry Development Fund.The authors propose to create a Defence Industry Development Fund using public and private sources of funding not prohibited by the legislative framework of Ukraine, which will expand the capabilities of defence industry enterprises to produce weapons and military equipment. The creation of a system of multi-level continuous education in the defence industry and long-term conditions for the sustainable development of the defence industry's human resources will allow to engage in capacity building and reach a new level of support for the Armed Forces of Ukraine through the implementation of NATO standards.
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