Helical Pitch Research Articles

Imaging with a twist: Three-dimensional insights of the chiral nematic phase of cellulose nanocrystals via SHG microscopy.

Cellulose nanocrystals (CNCs) are bio-based nanoparticles that, under the right conditions, self-align into chiral nematic liquid crystals with a helical pitch. In this work, we exploit the inherent confocal effect of second-harmonic generation (SHG) microscopy to acquire highly resolved three-dimensional (3D) images of the chiral nematic phase of CNCs in a label-free manner. An in-depth analysis revealed a direct link between the observed variations in SHG intensity and the pitch. The highly contrasted 3D images provided unprecedented detail into liquid crystal's native structure. Local alignment, morphology, as well as the presence of defects are readily revealed, and a provisional framework relating the SHG response to the orientational distribution of CNC nanorods within the liquid crystal structure is presented. This paper illustrates the numerous benefits of using SHG microscopy for visualizing CNC chiral nematic systems directly in the suspension-liquid phase and paves the road for using SHG microscopy to characterize other types of aligned CNC structures, in wet and dry states.

Evaluation of automatic tube current modulation in a CT scanner using a customised homogeneous phantom

Objective.The introduction of automatic tube current modulation (ATCM) has resulted in complex relationships between scanner parameters, patient body habitus, radiation dose, and image quality. ATCM adjusts tube current based on x-ray attenuation variations in the scan region, and overall patient dose depends on a combination of factors. This work aims to develop mathematical models that predict CT radiation dose and image noise in terms of attenuating diameter and all relevant scanner parameters.Approach.A homogenous phantom, equipped with the features to conduct discrete and continuous adaption tests, was developed to model ATCM in a Philips CT scanner. Scanner parameters were varied based on theoretical dose relationships, and a MATLAB script was developed to extract data from DICOM images. R statistical software was employed for data analysis, plotting, and regression modelling.Main Results.Phantom data provided the following insights: Median tube current decreased by 81% as tube potential varied from 80 kVp to 140 kVp. Doubling the DoseRight Index (DRI) from 12 to 24, at 24 cm diameter, produced a 294% increase in mA and a 46% decrease in noise. Mean mA increased by 53% whilst mean noise increased by 5.7% as helical pitch increased from 0.6 to 0.925. Changing rotation time from 0.33s to 0.75s gave a 56% reduction in mean mA and no change in image noise. Increasing detector collimation (n×T) resulted in higher tube currents and lower output image noise values, asnandTwere varied independently. Interpreting these results to apply transformations relevant to each independent variable produced models for tube current and noise with adjusted R-squared values of 0.965 and 0.912, respectively.Significance.The models developed more accurately predict radiation dose and image quality for specific patients and scanner settings. They provide imaging professionals with a practical tool to optimize scan protocols according to patient diameters and clinical objectives.

Synthesis and Properties of Highly Tilted Antiferroelectric Liquid Crystalline (R) Enantiomers.

This work reports the synthesis method and various properties of four rod-like antiferroelectric (R) laterally substituted enantiomers, with or without fluorine atoms used as substituents in the benzene ring. The influence of fluorine substitution on the mesophase temperature range was determined. The synthesized compounds are three-ring rod-like smectics with a chiral center based on (R)-(-)-2-octanol. Their chemical and optical purity was checked using high-performance liquid chromatography (HPLC). Two newly synthesized enantiomers and three previously reported (R) enantiomers were used to formulate two antiferroelectric mixtures. The mesomorphic behavior was characterized by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction (XRD). The helical pitch and tilt angle measurements were done using the selective light reflection phenomenon and the electro-optical method, respectively. All the enantiomers exhibit a wide temperature range of the antiferroelectric phase, with a high tilt angle. Furthermore, the enantiomer with lateral fluorine substitution in the ortho position has a very long helical pitch (more than 2.0 µm), relatively low enthalpy of melting point, and a tilt angle close to 45 degrees. The designed (R) enantiomers can be useful for formulating eutectic mixtures for further use in various devices, including photonics and optoelectronics.

Multi-stage and multi-colour liquid crystal reflections using a chiral triptycene photoswitchable dopant.

The photomodulation of the helical pitch of cholesteric liquid crystals results in dynamic and coloured canvases that can potentially be used in applications ranging from energy-efficient displays to colour filters, anti-counterfeiting tags and liquid crystal (LC) lasers. Here we report on the analysis of a series of photoswitchable chiral dopants that combine the large geometrical change and bistability of hydrazone switches with the efficient helical pitch induction of the chiral motif, triptycene. We elucidate the effects that conformational flexibility, dispersion forces and π-π interactions have on the chirality transfer ability of the dopant. We then use the irradiation time with visible light (442 nm) combined with a simple digital light processing microscope projection set-up to draw numerous stable multi-coloured images on an LC canvas, showcasing the fine control this dopant yields over the LC assembly.

Heat transfer enhancement of PCM in the triple-pipe helical-coiled latent heat thermal energy storage unit and complete melting time correlation

Secondary flows induced in helical-coiled pipes significantly enhance the thermal storage performance of latent heat thermal energy storage units. This paper presents a three-dimensional model of a triple-pipe helical-coiled system to investigate the melting characteristics of phase change material within it. A correlation for the complete melting time was developed based on the simulation results. The findings indicate that the thermal-hydraulic fields of the heat transfer fluids and phase change material deflect from the vertical central axis at cross-sections. The secondary flows within the inner pipe are more effective in enhancing melting than those in the outer pipe. Melting performance improves with increasing inner pipe diameter, coil diameter (from 100 mm to 160 mm), inclination angle, or heat transfer fluid temperature, or decreasing helical pitch. The inner pipe diameter, helical pitch and heat transfer fluid temperature exhibit more pronounced influences. An inner pipe diameter of 30 mm, a coil diameter of 160 mm, a helical pitch of 80 mm, an inclination angle of 90°, a heat transfer fluid temperature of 360 K, and a heat transfer fluid Reynolds number of 2000, respectively produce a faster melting process. The developed correlation for the triple-pipe helical-coiled pipe thermal storage unit accurately predicts 96 % of the 45 data within ±11 %.

Topological-charge-tunable and wavelength- switchable vortex laser enabled by a helically twisted high-absorption few-mode erbium-doped fiber.

Vortex beams carrying orbital angular momentum (OAM) offer a solution for enhancing spatial degrees of freedom, particularly in conjunction with wavelength division multiplexing, which can significantly boost data capacity for optical communication. Addressing the increasing demand for high information-carrying capacity, we present a dynamically tunable OAM laser source in this study. We demonstrate a ring-cavity vortex fiber laser employing intra-cavity mode conversion through a helically twisted high-absorption few-mode erbium-doped fiber (HA-FM-EDF). The constructed vortex fiber laser exhibits wavelength switchability via an integrated Sagnac loop, facilitated by a homemade ring-core fiber. Furthermore, topological-charge tunability is achieved through the utilization of twisted HA-FM-EDF with varying helical pitches. To our knowledge, this marks the first successful implementation of two-dimensional multiplexing of wavelength and OAM in a vortex fiber laser. The OAM laser serves as a versatile vortex source with high tunability and flexibility, holding significant potential for deployment in ultrahigh-speed/ultrahigh-capacity communications, ultrahigh-resolution imaging, and ultrahigh-sensitivity sensing applications.

CT imaging using variable helical pitch scanning for lower extremity arterial disease: Reduced contrast medium dose, improved image quality and diagnostic accuracy

ObjectivesThis study aimed to explore the feasibility of reducing contrast medium (CM) volume, improving image quality and diagnostic accuracy using variable helical pitch (VHP) scanning for patients with lower extremity arterial disease (LEAD). Materials and MethodsEighty patients who underwent lower extremity CT angiography (CTA) were prospectively enrolled and randomly assigned to either the VHP group (n = 40) or the conventional group (n = 40). Quantitative parameters and qualitative scores were compared between the two groups. Additionally, out of these patients, 72 arteries from 18 patients had DSA as the reference standard, and the diagnostic accuracy for the degree of vessel stenosis was assessed and compared. ResultsIn the VHP group, the contrast volume was significantly lower than in the conventional group (79.55 ± 11.87 mL vs. 89.63 ± 10.03 mL, p < 0.001), showing a reduction of 12.7 %. For all image quality characteristics, scores in VHP group were significantly superior to those in the conventional groups (all p < 0.05). Quantitative analysis revealed that images from the VHP group exhibited superior CT enhancement, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in the anterior tibial arteries (ATA) and dorsali pedis arteries (DPA) compared to the conventional group (all p < 0.001). Moreover, segment-based analysis showed the VHP group had significantly higher positive predictive value (PPV) and accuracy than the conventional group (PPV: 100 % vs. 76.19 %, p = 0.01; accuracy: 100 % vs. 84.38 %, p = 0.01, respectively). ConclusionsThe implementation of the VHP protocol led to a 12.7% decrease in contrast medium dosage compared to the conventional lower extremity CTA scanning protocol. Furthermore, it improved image quality and diagnostic accuracy, particularly for arteries below the knee.

Self‐Assembled Biconvex Microlens Array Using Chiral Ferroelectric Nematic Liquid Crystals

AbstractRecently, it is shown (Popov et al, Sci. Rep, 2017, 7, 1603) that chiral nematic liquid crystal films adopt biconvex lens shapes underwater, which may explain the formation of insect eyes, but restrict their practical application. Here it is demonstrated that chiral ferroelectric nematic liquid crystals, where the ferroelectric polarization aligns parallel to the air interface, can spontaneously form biconvex lens arrays in air when suspended in submillimeter‐size grids. Using Digital Holographic Microscopy, it is shown that the lens has a paraboloid shape and the curvature radius at the center decreases with increasing chiral dopant concentration, i.e., with decreasing helical pitch. Simultaneous measurements of the imaging properties of the lenses show the focal length depends on the pitch, thus offering tunability. The physical mechanism of formation of the self‐assembled ferroelectric nematic microlenses is also discussed.

Controlling the Helical Pitch of Foldamers Through Terminal Functionality: A Solid State Study.

Developing new methods to control the size and shape of the helical structures adopted by foldamers is highly important as the secondary structure displayed by these supramolecular scaffolds often dictates their activity and function. Herein, we report on a systematic study demonstrating that the helical pitch of ortho-azobenzene/2,6-pyridyldicarboamide foldamers can be readily controlled through the nature of the terminal functionality. Remarkably, simply through varying the end group of the foldamer, and without modifying any other structural features of the scaffold, the helical pitch can be over doubled in magnitude (from 3.4 Å to 7.3 Å). Additionally, crystallographic analysis of a library ten foldamers has identified general trends in the influence of a range of terminal functionalities, including carboxylbenzyl (Cbz), diphenylcarbamyl (N(Ph)2), ferrocene (Fc) and tert-butyloxycarbonyl (Boc), in controlling the folding behaviour of these supramolecular scaffolds. These studies could prove useful in the future development of functional foldamers which adopt specific sizes and shapes.

Possibility to measure the volume of coronary sinus in contrast-enhanced computed tomography.

Modern imaging techniques such as computed tomography (CT) can help in the assessment of coronary sinus volume in a vitro manner, but there is no comprehensive research on this topic so far. Hence, we decided to develop a methodology for measuring the volume of the coronary sinus in multi-detector CT and to try to apply it in practice. Forty-nine patients (22 men) were included in this research, with a mean age of 70.08 ± 13.6 years. Scanning with retrospective ECG-gating was performed using a Toshiba Aquilion 64 (slice: 0.5 mm; helical pitch: 12.8; rotation time: 0.4 s). 80 ± 20 cm3 of non-ionic contrast was administered to each patient. The volume of coronary sinus and other data measurements were performed using Vitrea 2 workstations. The organ volume measurement function was used to measure volume objects in CT scans. To standardise the measurements, they were all performed to the place where the vein of Marshall reaches the coronary sinus. In cases of loss of vein of Marshall, the first lateral vein was used as the junction between the coronary sinus and the great cardiac vein. The coronary sinus volume varied from 0.96 cm3 to 8.52 cm3. The average volume was 3.71 ± 1.64 cm3. There was a significant correlation between end diastolic volume and coronary sinus volume (r = 0.33, p = 0.02). In most cases the quality of visualisation was good - the average was calculated as 4.16 ± 0.87. The Thebesian valve was present in 22 cases (44.9%); however, no statistical relationship between the presence of the Thebesian valve and coronary sinus was observed. It is possible to visualise and calculate the volume of the coronary sinus in cardiac CT.

Numerical and experimental evaluation of the performance of agravitational vortex turbine rotor

In this study, the evaluation of the rotor performance of agravitational vortex turbine (TVG) for its application indistributed power generation is presented. A numerical analysiswas carried out on a specific configuration of a TVG,characterized by its spiral inlet and conical discharge. Thedimensions of the discharge chamber and the inlet channel, suchas the inlet channel width (w), length (L), and height (h), thedischarge cone height (H) and diameter (d), and the envelopeangle (γ) were determined through previous optimization studiesdocumented in the literature. These dimensions are related to thebasin diameter (D), which was set at 500 mm for this study. Theratios used, such as L/D, h/D, H/D, γ w/D and d/D were 1.518,0.565, 1.572, 92.41°, 0.362, and 0.108, respectively.The rotor has a curvature and a helical pitch angle of 68.8°, has 6blades, a rotor height of 200 mm and the middle section of therotor is 314.4 mm (0.4H) from the top of the discharge cone, withan lower and upper diameter of151.60 mm and 284.44 mm. Usinga three-dimensional computational domain and unsteady flowsimulations, efficiency curves as a function of angular velocitywere obtained. In addition, the TVG was manufactured andexperimental tests were carried out on a laboratory-scale testbench to validate its performance. These tests allowed us tocompare the experimental results (33.84% at 88 RPM) with thenumerical results (32.67% at 106,667 RPM), revealing adifference of 3.37% between the maximum efficiency values. Itis essential to continue the turbine optimization process to ensurethat the designed TVG plays a role in fostering sustainability andfacilitating the shift towards cleaner and sustainable energyalternatives.

Effect of spring-wire turbulators with different shapes on heat transfer improvement of solar air heaters; A numerical simulation

This study evaluates the heat transfer and performance characteristics of a solar air heater (SAH) equipped with spring-wire turbulators using a 3D verified CFD simulation process. Five different shapes of spring-wire (as shown in the graphical abstract) are investigated and compared to a flat SAH (without turbulator). The effects of helical diameter, pitch, and wire diameter on the performance of the system are comprehensively analyzed for all five mentioned geometries. The results reveal that the turbulator significantly enhances the thermal efficiency of the SAH within the absorber section. Rectangular cross section shape shows higher enhanced Nu number compared to the other cross section shapes. However, considering both heat transfer and pressure drop, the circular turbulator exhibits the optimal performance. Larger helical diameter, helical pitch and wire diameter, augments, decreases and increases the value of Nu/Nus respectively. Generally, higher increased Nu number also shows higher pumping power as well and that is why thermohydraulic performance parameter (THPP) is considered as well. Larger helical diameter, and helical pitch decreases and increases thermohydraulic performance respectively. For instance, the circular turbulator's THPP rises by approximately 17.5% as the pitch increases from 50 mm to 250 mm. However, the impact of wire diameter on THPP does not show a unified curve trend and depends on the shape of the turbulator. This study is remarkably useful for optimizing the performance of SAHs with turbulators, paving the way for enhanced device efficiency.

Helical-sampled fiber Bragg grating inscribed by a femtosecond laser in a ring core fiber.

The inscription of a helical-sampled fiber Bragg grating (HSFBG) in a ring core fiber (RCF) using a low repetition rate femtosecond laser point-by-point technique is demonstrated. The reflection spectrum exhibits several peak groups attributed to the helical-sampled structure, with the wavelength interval between different groups determined by the helical pitch. Meanwhile, the number and spacing of the peaks within each group are dictated by the RCF. An investigation into the effects of helical pitch, helical radius, and grating length of the HSFBG on the reflection spectra is conducted. Furthermore, thermal annealing experiments demonstrate that this HSFBG can survive at the temperatures up to 800°C.

Synthesis and Characterization of New Chiral Smectic Four-Ring Esters.

Orthoconic antiferroelectric liquid crystals (OAFLCs) represent unique self-organized materials with significant potential for applications in photonic devices due to their sub-microsecond switching times and high optical contrast in electro-optical effects. However, almost all known OALFCs suffer from low chemical stability and short helical pitch values. This paper presents the synthesis and study results of two chiral AFLCs, featuring a four-ring structure in the rigid core and high chemical stability. The mesomorphic properties of these compounds were investigated using polarizing optical microscopy and differential scanning calorimetry. Spectrometry and electro-optical studies were employed to estimate the helical pitch, tilt angle, and spontaneous polarization of the synthesized compounds and the prepared mixtures. All studied compounds exhibit enantiotropic chiral smectic mesophases including the SmA*, the SmC*, and a very broad temperature range of the SmCA* phase. Doping top-modern antiferroelectric mixture with synthesized compounds offers benefits such as increased helical pitch and tilt angle values without significantly influencing spontaneous polarization. This allows the prepared mixture to be regarded as an OAFLC with high optical contrast, characterized by an almost perfect dark state. These valuable physicochemical and optical properties suggest significant potential of studied materials for practical applications.

Dynamically crosslinked chiral optics sensing for ultra-sensitive VOCs detection

Chiroptical sensing with real-time colorimetrical detection has been emerged as quantifiable properties, enantioselective responsiveness, and optical manipulation in environmental monitoring, food safety and other trace identification fields. However, the sensitivity of chiroptical sensing materials remains an immense challenge. Here, we report a dynamically crosslinking strategy to facilitate highly sensitive chiroptical sensing material. Chiral nematic cellulose nanocrystals (CNC) were co-assembled with amino acid by a two-step esterification, of which a precisely tunable helical pitch, a unique spiral conformation with hierarchical and numerous active sites in sensing performance could be trigged by dynamic covalent bond on amines. Such a CNC/amino acid chiral optics features an ultra-trace amount of 0.08 mg/m3 and a high sensitivity of 60 nm/(mg/m3) for formaldehyde gas at a molecule level detection, which is due to the three synergistic adsorption enhancement of dynamic covalent bonded interaction, hydrogen bonded interaction and van der Waals interaction. Meanwhile, an enhancement hierarchical adsorption of CNC/amino acid chiral materials can be readily representative to the precise helical pitch and colorimetrical switch for sensitive visualization reorganization.

Numerical study of a CO2 swirl ejector with lubricating oil

At present, most simulations of ejectors ignore the presence of lubricating oil, which may affect the accuracy of the results. Additionally, there has been less research conducted on the influence of motive nozzles with swirl generators on the performance of ejectors. In this study, a heterogeneous mixture model was developed for a three-phase swirl ejector equipped with a motive nozzle featuring a swirl generator. This article examines the performance of swirl ejectors under supercritical conditions using three-dimensional numerical simulations conducted in ANSYS. The study explores swirl ejectors with varying helical angles of 77°, 64°, 58°, 50°, 37° . The study also takes into account the influence of lubricating oil to enhance the practicality of the research. Firstly, lubricating oil with a volume fraction of 2 % was introduced into both the motive and suction streams, followed by conducting an ejection analysis. The results indicate that the swirl enhances the entrainment ratio, and the swirl strength can be modified by changing the helical angle. A smaller helical angle results in greater swirl strength and a higher entrainment ratio. When the helical angle is 37° and the helical pitch is 20 mm, a swirl number of 0.42, an entrainment ratio of 0.998, and an effective entrainment ratio of 0.863 is achieved. However, when the oil circulation ratio in the suction stream is increased from 2 % to 10 % while keeping the oil circulation ratio of the motive stream constant, the entrainment ratio decreases.

Study on Structural Design and Motion Characteristics of Magnetic Helical Soft Microrobots with Drug-Carrying Function.

Magnetic soft microrobots have a wide range of applications in targeted drug therapy, cell manipulation, and other aspects. Currently, the research on magnetic soft microrobots is still in the exploratory stage, and most of the research focuses on a single helical structure, which has limited space to perform drug-carrying tasks efficiently and cannot satisfy specific medical goals in terms of propulsion speed. Therefore, balancing the motion speed and drug-carrying performance is a current challenge to overcome. In this paper, a magnetically controlled cone-helix soft microrobot structure with a drug-carrying function is proposed, its helical propulsion mechanism is deduced, a dynamical model is constructed, and the microrobot structure is prepared using femtosecond laser two-photon polymerization three-dimensional printing technology for magnetic drive control experiments. The results show that under the premise of ensuring sufficient drug-carrying space, the microrobot structure proposed in this paper can realize helical propulsion quickly and stably, and the speed of motion increases with increases in the frequency of the rotating magnetic field. The microrobot with a larger cavity diameter and a larger helical pitch exhibits faster rotary advancement speed, while the microrobot with a smaller helical height and a smaller helical cone angle outperforms other structures with the same feature sizes. The microrobot with a cone angle of 0.2 rad, a helical pitch of 100 µm, a helical height of 220 µm, and a cavity diameter of 80 µm achieves a maximum longitudinal motion speed of 390 µm/s.

Aptameric photonic structure-based optical biosensor for the detection of microcystin

An optical photonic biosensor for the detection of microcystin (MC) has been developed using an aptamer-immobilized interpenetrating polymeric network (IPNaptamer) intertwined with solid-state cholesteric liquid crystals (CLCsolids). The IPN was constructed with a polyacrylic acid hydrogel (PAA). Aptamer immobilization enhances polarity while blocking hydrogen bonding between the carboxylic groups of PAA-IPN hydrogel, thereby increasing the swelling ratio of the PAA-IPN hydrogel. This leads to an expansion in the helical pitch of the corresponding IPNaptamer-CLCsolid biosensor chip and results in a red-shift in the reflected color. Upon exposure to an aqueous MC solution, the IPNaptamer-CLCsolid biosensor chip exhibits aptamer-mediated engulfment of MC, resulting in reduced polarity of the IPNaptamer complex and a consequential blue-shift in the biosensor chip color occurred. The wavelength shift of the IPNaptamer-CLCsolid biosensor chip demonstrates a linear change with an increase in MC concentration from 3.8 to 150 nM, with a limit of detection of 0.88 nM. This novel optical biosensor is characterized by its low cost, simplicity, selectivity, and sensitivity, offering a promising strategy for designing similar toxin biosensors through the modification of biological receptors.

Left and Right‐Handed Light Reflection and Emission in Ultrathin Cellulose Nanocrystals Films with Printed Helicity

AbstractNatural polymers, particularly plant‐derived nanocelluloses, self‐organize into hierarchical structures, enabling mechanical robustness, bright iridescence, emission, and polarized light reflection. These biophotonic properties are facilitated by the assembly of individual components during evaporation, such as cellulose nanocrystals (CNCs), which exhibit a left‐handed helical pitch in a chiral nematic state. This work demonstrates how optically active films with pre‐programmed opposite handedness (left or right) can be constructed via shear‐induced twisted printing with clockwise and counter‐clockwise shearing vectors. The resulting large‐area thin films are transparent yet exhibit pre‐determined mirror‐symmetrical optical activity, enabling the distinction of absorbed and emitted circularly polarized light. This processing method allows for sequential printing of thin and ultrathin films with twisted layered organization and on‐demand helicity. The complex light polarization behavior is due to step‐like changes in linear birefringence within each deposited layer and circular birefringence, different from that of conventional CNC films as revealed with Muller matrix analysis. Furthermore, intercalating an achiral organic dye into printed structures induces circularly polarized luminescence while preserving high transmittance and controlled handedness. These results suggest that twisted sequential printing can facilitate the construction of chiroptical metamaterials with tunable circular polarization, absorption, and emission for optical filters, encryption, photonic coatings, and chiral sensors.

Responsive cellulose nanocrystal / acrylamide / poly (ethylene glycol) photonic films with chiral nematic structures by co-assembly and photopolymerization

Cellulose nanocrystals (CNCs), acrylamide (AAm) and poly (ethylene glycol) (PEG) can be co-assembled and photopolymerized into responsive, patterned photonic films with chiral nematic (N*) structures. Here, we report stimuli-responsive CNC/AAm/ PEG composite films (CFs) for use in humidity sensing. With the increase of AAm content, the CFs had an increased helical pitch and showed a red shift. With the adding of PEG, the CFs can quickly capture or release water molecules in air, which resulted in the changes of the helical pitch in N* structures and the structural color. After photopolymerization, the elastic modulus, hardness by nanomechanical testing and tensile strength of polymer films (PFs) were improved compared with CFs. The elastic modulus and hardness of PFs increased with the increase of AAm content. PFs and CFs showed different swelling properties in solutions with different EtOH / H2O ratio. Due to the swelling properties difference between CFs and PFs, partial photopolymerized photonic film showed photonic pattern. This research provides a new method to prepare photonic films with sensitive color response to humidity and photonic pattern, which has potential applications in the fields of sensing, anti-counterfeiting, and decoration.