Crystalline (<italic>E</italic>)-4-fluoro-cinnamaldehyde malononitrile undergoes a [2+2] photocycloaddition, leading to robust photomechanical response and improved force generation by nanowire ceramic composites.

Wastewater analysis of pathogens, particularly SARS-CoV-2, is instrumental in tracking and monitoring infectious diseases a population. This method can be used to generate early warnings regarding the onset an disease predict associated infection trends. Currently, wastewater SARS-CoV-2 almost exclusively performed using polymerase chain reaction for amplification-based detection viral RNA at centralized laboratories. Despite development several biosensing technologies offering point-of-care...

Expo parks are characterized by dense crowds and a high risk of accidents. A multi-robot patrolling system equipped with multiple sensors can provide personalized services to visitors quickly locate emergencies, effectively accelerating response times. This study focuses on developing efficient strategies for systems. In expo parks, this requires solving the traveling salesman problem (MTSP) addressing obstacle avoidance in static environments. The main challenge is plan paths allocate tasks...

Abstract Nanostructured materials have enabled new ways of controlling the light–matter interaction, opening routes for exciting applications, in display technologies and colorimetric sensing, among others. In particular, metallic nanoparticles permit production color structures out colorless materials. These plasmonic structural colors are sensitive to environment thus offer an interesting platform sensing. Here, a self‐assembly aluminum close proximity mirror is spaced by ultrathin poly( N...

Abstract Porous anodic aluminum oxide (AAO) membranes template the growth of photochromic crystalline nanowires. The resulting organic–inorganic composite can function as a photomechanical bending actuator. In order to investigate how nanostructural properties both organic and inorganic components affect response, mechanical are characterized using variety methods. There is significant variation in morphology elastic modulus for two commercially available AAO templates with nominally...

Photomechanical materials perform mechanical work in response to illumination. Photoisomerization-based photomechanical may operate different regimes depending on the intensity of illuminating light. We examine photoresponse liquid crystalline azo-acrylate networks and show that a material property, characteristic material, defines boundaries between regimes. Asymptotic analysis indicates whereas at low relative light levels, photostress is proportional intensity, high it fluence. Model...

The determination of the mechanical properties materials is important for creation physical models and describing mechanisms converting diverse stimuli into response. It critical design nanoscale transducers, sensors, actuators such as motors, pumps, artificial muscles medical microrobots. This paper reports measurement five independent elastic constants a transversely isotropic liquid crystal elastomer. We express EL, ET, G12, k12, G23 in terms strains stresses, then measure these determine...

Room-temperature longwave infrared (LWIR) detectors are preferred over cryogenically cooled solutions due to the cost effectiveness and ease of operation. The performance present uncooled LWIR such as microbolometers, is limited by reduced sensitivity, slow response time, lack dynamic spectral tunability. Here, we a graphene-based efficient room-temperature detector with high detectivity fast time utilizing its tunable optical electronic characteristics. inherent weak light absorption...

Hybrid organic-inorganic composites based on organic photochromic crystals embedded in inorganic templates provide a new approach to photomechanical materials. Diarylethene (DAE) nanowire grown Al

We demonstrate a small optical bench footprint laser assembly based on the pulsed Nd:YAG head SSY-1 for pumping cholesteric liquid crystal (CLC) lasers and illustrate its performance using low molecular weight CLC samples doped with fluorescent dye PM597. A lasing threshold, narrow line, far-field interference patterns of were observed SSY-1-based as pump. The emission characteristics are similar to those comparable materials pumped by an order magnitude physically larger many orders more...

Fascination with nature's color palette has propelled mankind's efforts to imitate and surpass it. Apart from the traditional interests in brighter more fade-resistant colors, present time adds need for doing so without impacting environment based on nontoxic materials. Although most commercial colorants are chemical pigments that absorb wavelengths of light matching their electronic molecular transitions, development nanofabrication techniques last decades spurred researchers study...

We developed and implemented an experimental setup for the generation of high-energy high-order harmonics in argon gas nonlinear experiments extreme ultraviolet (XUV) spectral range. High-order were generated by loosely focusing a laser pulse centered around 800 nm into cell filled with phase-matching condition. The wavefront distortions driving corrected deformable mirror, XUV conversion efficiency was significantly improved due to excellent beam profile at focus. A high-damage-threshold...

Cholesteric liquid crystals are frequently produced by the addition of chiral dopants to achiral nematic hosts. We report here synthesis and performance obtained from bio-betulin a fermentation process. An important aspect this work is point out that process used obtain starting materials much easier cheaper when carried in large volumes than isolating it natural product. The indistinguishable those commercially available synthetic betulin.

An improved particle swarm optimization method is proposed for the design of ultra-thin diffractive optical elements (DOEs) enabling multicolour beam shaping functionality. We employ pre-optimized initial structures and adaptive weight strategy in algorithm to achieve better identical performance multiple colours. Accordingly, a DOE light from green blue LEDs has been designed fabricated. Both experiment numerical simulations have conducted results agree well with each other. 15.66% average...

In this paper, we propose a suitable surface energy expression for cholesteric liquid crystals. We show that there exists symmetry allowed term chiral nematics doesn’t appear in the traditional Rapini-Papoular form. discuss some consequences of new anchoring term.

Abstract This paper first analyzes the definition of computer VR technology and transmission information data, then expounds how to use establish a complete digital media design system; Finally, deeply application in system, including detailed discussion planning user interaction, dissemination mode reception mode. According current situation development China, is introduced improve operation process media, so that system can be improved.

With regard to optical diffusers, the configuration parameters is determined according need of application including beam shape, homogeneity, diffusing angle, transmittance etc. Differentiating with conventional diffuser design methods such as diffractive element (DOE) methods, we proposed a method microlens array (MLA) configured random-distributed parameter for generation large angle and uniform intensity distribution. And discussed relation between homogeneity random distribution type...

It has been demonstrated in the past that high fluxes of extreme ultraviolet (XUV) light could be obtained by driving harmonic generation (HHG) with energy lasers.However, peak intensity at focal point a femtosecond laser more than 100 mJ can too for phase-matched HHG gases.We propose method to optimize spatial profile off-focus locations avoid fully ionizing target atoms.The beam before or after depends on wavefront quality and near field distribution.The spot diameter reaches three times...

Cholesteric liquid crystals are tunable self-assembled photonic bandgap materials. Because of their unusual properties and potential for applications in photonics, optical have received considerable attention. Models describing light propagation cholesterics typically focus primarily on structure anisotropy. Here we the chirality constituents, discuss its consequences dielectric other than material structure.

We are interested in understanding the behavior of nematics inhomogeneous external fields, and investigating possibility field induced biaxiality. report results our studies optical response nematic 4-cyano-4′-pentylbiphenyl (5CB) sandwiched between two circular glass substrates, with homeotropic alignment, to a spatially varying magnetic at room temperature. The radially symmetric is generated by ring rare earth magnets. describe experimental setup, preliminary results, indicate future...

Holographic diffuser with designed beam shaping functionality is of significance for various applications in lighting and display industry. We investigate the efficient optimization on a Computer Generated Hologram (CGH) design, to enable holographic multi-band shaping. Both synthetic experimental demonstrations are presented.

Symmetry arguments constitute one of the most powerful tools physics. As shown by Emmy Noether, continuous symmetries correspond to physical conservation laws. In analogy with dimensional arguments, symmetry can also be used predict behaviour systems. Mistaking symmetries, on other hand, lead grave errors. this paper, we describe and give examples certain types which useful in general and, particular, field liquid crystals. using phenomena, totalitarian principle, made popular Murray...

Increasingly important photomechanical materials produce stress and mechanical work when illuminated. We propose experimentally accessible performance metrics for photostress photowork, enabling comparison of performance. relate these to material properties, providing a framework the design optimization materials.

Much is known about the Freedericksz transition induced by uniform electric and magnetic fields in nematic liquid crystals. In this work, we are interested effects of a spatially varying field on transition. Specifically, study director configuration homeotropic cell with cylindrical symmetry. The experiment conducted ring magnet which provides radial magnitude monotonically decreasing to zero at center. positioned central plane ring, normal parallel normal. Interference patterns between...