Developing a new class of innovative high performance optical infrared imagers

Many materials and additives perform well as fire retardants and suppressants, but there is an ever-growing list of unfulfilled demands requiring new developments. This work explores the outstanding dispersant and adhesive performances of cellulose to create a new effective fire-retardant: exfoliated and reassembled graphite (ERG). This is a new 2D polyfunctional material formed by drying aqueous dispersions of graphite and cellulose on wood, canvas, and other lignocellulosic materials, thus producing adherent layers that reduce the damage caused by a flame to the substrates. Visual observation, thermal images and surface temperature measurements reveal fast heat transfer away from the flamed spots, suppressing flare formation. Pinewood coated with ERG underwent standard flame resistance tests in an accredited laboratory, reaching the highest possible class for combustible substrates. The fire-retardant performance of ERG derives from its thermal stability in air and from its ability to transfer heat to the environment, by conduction and radiation. This new material may thus lead a new class of flame-retardant coatings based on a hitherto unexplored mechanism for fire retardation and showing several technical advantages: the precursor dispersions are water-based, the raw materials used are commodities, and the production process can be performed on commonly used equipment with minimal waste.

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A three-dimensional hierarchical Fe2O3@NiO core/shell nanorod array on carbon cloth: a new class of anode for high-performance lithium-ion batteries

Nanoscale ◽

10.1039/c3nr02258g ◽

2013 ◽

Vol 5 (17) ◽

pp. 7906 ◽

Cited By ~ 126

Author(s):

Qin-qin Xiong ◽

Jiang-ping Tu ◽

Xin-hui Xia ◽

Xu-yang Zhao ◽

Chang-dong Gu ◽

...

Keyword(s):

Lithium Ion Batteries ◽

High Performance ◽

Three Dimensional ◽

Lithium Ion ◽

Nanorod Array ◽

Core Shell ◽

Carbon Cloth ◽

New Class

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Theoretical Studies of the Physical Properties of Rodlike and Related Polymers

MRS Proceedings ◽

10.1557/proc-134-621 ◽

1988 ◽

Vol 134 ◽

Cited By ~ 2

Author(s):

W. J. Welsh ◽

J. E. Mark ◽

Y. Yang ◽

G. P. Das

Keyword(s):

High Performance ◽

Liquid Crystalline ◽

Theoretical Work ◽

Environmental Resistance ◽

New Class ◽

Protonated Forms ◽

New Type ◽

Electrooptical Properties ◽

Cis And Trans ◽

Strong Acids

ABSTRACTThis review focuses on a new type of para-catenated aromatic polymer being used in the preparation of high-performance films and fibers of exceptional strength, thermal stability, and environmental resistance, including inertness to essentially all common solvents. Polymers of this type include the cis- and trans-poly(p-phenylene benzobisoxazole) (PBO), the cis- and trans-forms of the corresponding poly(pphenylene benzobisthiazole) (PBT), and the structurally similar poly(5,5ʹ-bibenzoxazole-2.2ʹ-diyl-l,3-phenylene) (AAPBO) and poly(2,5-benzoxazole) (ABPBO) and their sulfurcontaining analogues. Because of their rigidity, these polymers become highly oriented in solution and some display liquid crystalline behavior. The purpose of this paper is to summarize the authorsʹ theoretical work on the structures, conformational energies, intermolecular interactions, electronic properties, electrical conductivity, and electrooptical properties of these chains, including, in some cases, the so-called articulated forms and the protonated forms known to exist in strong acids. The emphasis is on how such studies provide a molecular understanding of the unusual properties and processing characteristics of this new class of materials.

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A new class of high-performance thermoset resins using dicyanoimidazole (DCI) as crosslinking group: A key demo of synthesis, curing behavior and thermal properties

Polymer ◽

10.1016/j.polymer.2021.124264 ◽

2021 ◽

pp. 124264

Author(s):

Zhengzhu Zhu ◽

Xian He ◽

Wei Tan ◽

Jinlang Hong ◽

Shenjun Liao ◽

...

Keyword(s):

Thermal Properties ◽

High Performance ◽

Curing Behavior ◽

Thermoset Resins ◽

New Class ◽

Group A

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MSV(L): Continuing the Legacy of Army Waterborne Capability

10.5957/smc-2021-113 ◽

2021 ◽

Author(s):

David Richard Toepler ◽

Nathan Leightner

Keyword(s):

United States ◽

United States Army ◽

High Performance ◽

The United States ◽

Engineering Management ◽

Fourth Quarter ◽

Detailed Design ◽

New Class ◽

Source Selection ◽

Primary Mission

The United States Army operates several classes of landing craft, which provide combatant commanders with waterborne maneuver capabilities essential for accomplishing a range of critical missions unique to the Army. These missions involve transport of personnel, cargo, and equipment from advanced bases and large sealift ships to ports, inland riverine regions, as well as remote undeveloped coastlines and beaches. Recognizing the significant roles these vessels play and will continue to play in achieving Army objectives, Army leadership allocated funding to design and build a new class of high performance landing craft: Maneuver Support Vessel (Light) (MSV(L)). The primary mission of MSV(L) is to conduct movement and maneuver of combat-configured Brigade Combat Team force elements such as one M1A2 main battle tank, or two Stryker vehicles, or four Joint Light Tactical Vehicles, each with its crew. MSV(L) will have beaching capability and be able to operate at speeds significantly in excess of any current Army landing craft. The Army Watercraft Systems organization was tasked with overseeing development of requirements and specifications, source selection and acquisition, along with contract, finance, and engineering management of the MSV(L) Program. A contract to develop the detailed design and build a series of vessels was awarded in September 2017. Launch of the initial vessel is planned during the fourth quarter of 2021.

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Tunable ultra-uniform Cs4PbBr6 perovskites with efficient photoluminescence and excellent stability for high-performance white light-emitting diodes

Journal of Materials Chemistry C ◽

10.1039/d1tc02210e ◽

2021 ◽

Author(s):

Yao Li ◽

Kaimin Du ◽

Manli Zhang ◽

Xuan Gao ◽

Yu Lu ◽

...

Keyword(s):

White Light ◽

High Performance ◽

Light Emitting Diodes ◽

Metal Halide ◽

Light Emitting ◽

New Class ◽

Halide Perovskites ◽

White Light Emitting Diodes ◽

Lead Halide ◽

Excellent Stability

Metal halide perovskites are a new class of promising materials in optoelectronic applications. As optoelectronic properties of the lead halide perovskites are determined largely by their morphology, the morphology of...

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Liquid crystal thermosets. A new class of high-performance materials

Liquid Crystals ◽

10.1080/02678292.2019.1641233 ◽

2019 ◽

Vol 47 (13) ◽

pp. 2016-2026 ◽

Cited By ~ 3

Author(s):

Francesco Vita ◽

Fabrizio C. Adamo ◽

Michela Pisani ◽

Leah M. Heist ◽

Ming Li ◽

...

Keyword(s):

Liquid Crystal ◽

High Performance ◽

New Class

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On the Use of a New Class of Simplified Multi-Window Iris Notch in the Design of Ultra-Compact High-Rejection Waveguide Filters for Satellite Links

Electronics ◽

10.3390/electronics9081221 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1221

Author(s):

Juan Luis Cano ◽

Angel Mediavilla ◽

Antonio Tazon

Keyword(s):

High Performance ◽

Symmetry Plane ◽

Pass Band ◽

Transmission Zero ◽

New Class ◽

X Band ◽

Waveguide Filters ◽

Field Symmetry ◽

Insertion Losses ◽

First Time

This work introduces a simplified multi-aperture iris notch suitable for designing waveguide filters having an extremely improved compactness/rejection ratio, regarding available solutions, and adequate pass-band performances. The proposed iris architecture, analyzed for the first time, exhibits a unique transmission zero in the waveguide mono-mode bandwidth which can be easily located below or above the pass-band. The frequency of this transmission zero is evaluated in terms of the iris dimensions thus providing useful guidelines for designing filters with suitable responses. As a consequence of this simplified topology, any designed filter can be easily manufactured by cutting along its E-field symmetry plane. This strategy greatly improves the filter’s insertion loss regarding classical implementations based on more complicated arrangements with piled thin metallic sheets. Two exemplary filters have been designed and tested to be used in a high-performance X-band SATCOM terminal with an 80% size reduction with respect to the existing systems. Both filters covering the Rx (7.25–75 GHz) and Tx (7.9–8.4 GHz) sub-bands show a reflection of −25 dB with insertion losses below 1 dB in the pass-band, whereas they present a very sharp out-of-band rejection of at least 90 dB, that is, a 600 dB/GHz slope at X band.

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