Rich Color Research Articles

Collaborative design of landscape and lighting to improve visitors’ satisfaction with nightscapes

Visitors’ satisfaction with the nightscapes of urban green spaces is currently poorly understood, with existing literature mainly focusing on visitors’ satisfaction with daytime landscapes. Moreover, the collaborative design of landscape and lighting—two important factors determining satisfaction—remains unclear. This study conducted surveys on visitors’ satisfaction with nightscapes through a comparative assessment referring to the Federation Internationale de Football Association (FIFA) World Cup Rules. Statistical analysis revealed that: (1) more open spaces, rich colours, and a higher brightness could improve visitors’ satisfaction with nightscapes, while dazzle lighting reduced it; (2) brightness was conducive to visitors’ satisfaction, while enhancing brightness reduced the capacity of a nightscape to uniformly support the four components of satisfaction; and (3) increasing vegetation coverage could enhance this capacity. These findings provide reliable evidence to guide collaborative design that simultaneously considers landscape characteristics and lighting features, which facilitates the improvement of visitors’ satisfaction with nightscapes.

Metabolomics Combined with Transcriptomics Reveals the Formation Mechanism of Different Colored Flowers of Cosmos bipinnata Cav

In nature, plants have rich and vivid colors. Flower color can confer economic and ornamental value to ornamental plants, and is one of the target traits for current directed breeding. Therefore, it is essential to understand the molecular regulatory mechanisms behind flower color formation in ornamental plants. However, in Cosmos bipinnata Cav., one of the most important ornamental plants, the metabolic pathways and molecular regulatory mechanisms underlying the formation of different flower colors are not yet clear, which greatly restricts the molecular breeding of flower color varieties. We selected three varieties of Cosmos bipinnata Cav. with white, pink, and red flowers as research materials, and identified significantly different metabolites among them through ultra performance liquid chromatography mass spectrometry (UPLC-MS/MS) analysis and principal component analysis (PCA). Then, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and transcriptome sequencing analysis in different colors flowers were used to reveal that the differential metabolites were enriched in flavonoid metabolic pathways and related structural genes were differentially expressed. Furthermore, we identified differentially expressed members of the MYB and bHLH transcription factor families, which play key roles in regulating the anthocyanin biosynthesis. By constructing a phylogenetic tree and performing a joint analysis of transcriptome and metabolome data, we further elucidated the molecular regulatory network underlying the formation of flower colors in Cosmos bipinnata Cav. This study not only provides a theoretical basis and gene resources for color-oriented breeding and the creation of new color varieties, but also offers new insights into the molecular mechanisms of flower color formation in plants.

Solution for Environmentally Friendly Silver Surface Magnetron Sputtering Color Titanium Film Layer Technology

Silver is an elegant white precious metal, but it is easily oxidized by O3, SO2, and H2S in the air, turning yellow or dark, which affects its decorative effect. The existing silver coating, primarily prepared through the electroplating process, poses serious environmental pollution problems. It is necessary to seek new, green, and environmentally friendly coating processes while also enhancing the color palette of silver jewelry coatings. Titanium film layers were deposited on Ag925 and Ag999 surfaces using magnetron sputtering coating technology. The effects of sputtering time, substrate surface state, reaction gas type and time, and film thickness on the color of the film layers were studied, and the anti discoloration performance of the obtained film layers under the optimal process was tested. The experimental results show that when the sputtering time varies from 5 to 10 minutes, injecting argon, oxygen, and nitrogen into the coating chamber yields rich colors such as purple with a red tint, blue, yellow green, yellowish purple, and blue purple. The precise control of gas injection time has a significant impact on the color of the film layer. In terms of anti tarnish performance, the film showed good stability in the artificial sweat immersion test. From an environmental perspective, the magnetron sputtering titanium film process has no harmful gas or liquid emissions, which aligns with the sustainable development trend of the jewelry industry and holds great promise for application. This study has improved the visual effect and practical performance of the product, providing important theoretical basis and experimental data support for the application of environmentally friendly silver surface vacuum magnetron sputtering titanium thin film coating technology.

Recent Advances of Electrode Materials Applied in an Electrochromic Supercapacitor Device.

An electrochromic supercapacitor device (ESD) is an advanced energy storage device that combines the energy storage capability of a supercapacitor with the optical modulation properties of electrochromic materials. The electrode materials used to construct an ESD need to have both rich color variations and energy storage properties. Recent advances in ESDs have focused on the preparation of novel electrochromic supercapacitor electrode materials and improving their energy storage capacity, cycling stability, and electrochromic performance. In this review, the research significance and application value of ESDs are discussed. The device structure and working principle of electrochromic devices and supercapacitors are analyzed in detail. The research progress of inorganic materials, organic materials, and inorganic/organic nanocomposite materials used for the construction of ESDs is discussed. The advantages and disadvantages of various types of materials in ESD applications are summarized. The preparation and application of ESD electrode materials in recent years are reviewed in detail. Importantly, the challenges existing in the current research and recommendations for future perspectives are suggested. This review will provide a useful reference for researchers in the field of ESD electrode material preparation and application.

Preparation of colorful glass/W/V2O5 electrochromic electrodes by magnetron sputtering

Abstract V2O5, an inorganic electrochromic (EC) material with rich color variation and natural abundance, has received extensive attention due to its polychromatic properties during the EC process. However, research on achieving multicolor tuning by combining the structural color generated from the light-matter interactions with the EC properties of V2O5 is rare. Here, based on the detailed investigation of the process parameters of V2O5, we propose a new optical design of the colorful EC electrode with the V2O5/W Fabry–Pérot cavity constructed by magnetron sputtering on the glass substrate. By varying the thickness of the top layer of V2O5, the reflective electrodes exhibit seven different initial colors. Importantly, the designed EC electrode exhibits a vivid and rich wide color gamut when applying a voltage of −0.6–1.6 V. After 200 cycles, the color of the EC electrode and device can still change, demonstrating the potential of the glass/W/V2O5 EC electrodes in the fields such as camouflage and anti-counterfeiting.

Transcriptome and Metabolome Insights into Key Genes Regulating Fat Deposition and Meat Quality in Pig Breeds.

Meat quality is a complex trait that exhibits significant variation across pig breeds, and the regulatory mechanisms governing pork meat quality are not fully elucidated. We compared the transcriptomics and metabolomics of the longissimus dorsi (LD) muscle between the Songliao Black Pig (SBP) and Large White × Landrace Pig (LWLDP) to investigate breed-specific differences in meat quality and underlying regulatory pathways. The results showed that SBP meat had a higher marbling score and backfat thickness, a richer color, a lower shear force, and reduced drip loss. Fatty acid (FA) analysis identified 15 significant FAs in the LWLDP, with docosahexaenoic acid (DHA) in the SBP, while amino acid (AA) analysis revealed no breed-based differences. Transcriptome analysis identified 134 upregulated and 362 downregulated genes in the SBP. Protein-protein interaction (PPI) network analysis found 25 key genes, which are associated with muscle development, fat deposition, and overall meat quality, while genes in the insulin signaling pathway, such as PPP1R3B, PPARGC1A, SOCS1, EIF4E, PRKAR2A, PRKAG2, and FASN, play a crucial role in balancing fat metabolism and catabolism. Metabolomic analysis identified 89 upregulated and 10 downregulated metabolites in the SBP, primarily involved in fructose and mannose metabolism, amino acid biosynthesis, nucleotide sugar metabolism, and glucagon signaling pathways. Gene-metabolite association analysis found that the PPP1R3B gene had a strong association with Thr-Leu, Maltol, D-myo-Inositol-4-phosphate, and Fructose-6-phosphate, while MYOG correlated with Mannose-6-phosphate, Fructose-1-phosphate, Mannose-1-phosphate, and Glucose-6-phosphate. In contrast, NR4A3 and PPARGC1A showed a strong negative correlation with most upregulated metabolites. In conclusion, this study identified functional genes, elucidated the mechanisms associated with meat quality traits, and identified gene-metabolite associations involved in energy metabolism, muscle development, and fat deposition, providing valuable insights into the molecular mechanisms that regulate meat quality between pig breeds.

Structurally Colored Physically Unclonable Functions with Ultra‐Rich and Stable Encoding Capacity

AbstractIdentity security and counterfeiting assume a critical importance in the digitized world. An effective approach to addressing these issues is the use of physically unclonable functions (PUFs). The overarching challenge is a simultaneous combination of extremely high encoding capacity, stable operation, practical fabrication, and a widely available readout mechanism. Herein this challenge is addressed by designing an optical PUF via exploiting the thickness‐dependent structural color formation in nanoscopic films of ZnO. The structural coloration ensures authentication using widely available bright‐field‐based optical readout, whereas the metal oxide provides a high degree of structural stability. True physical randomness in spatial position is achieved by physical vapor deposition of ZnO through stencil masks that are fabricated by pore formation in polycarbonate membranes via photothermal processing of stochastically positioned plasmonic nanoparticles. Structural coloration emerges from thin film interference as confirmed via simulation studies. The rich color variation and stochastic definition of domain size and geometry result in chaotic features with an encoding capacity that approaches (6.4 × 105)(2752×2208). Deep learning‐based authentication is further demonstrated by transforming these chaotic features into unbreakable codes without field limitations. This ultra‐rich encoding capacity, coupled with outstanding thermal and chemical stability, forms a new cutting edge for state‐of‐the‐art PUF‐based encoding systems.

Vegetation diversity in structure, species or colour: Coupling effects of the different characteristics of urban green spaces on preference and perceived restoration

The benefits of urban green spaces for human beings have become increasingly evident amid global urbanisation, which has exacerbated health issues. However, the effects of different characteristics of urban green spaces, such as vegetation structure, species and colour, on human health and well-being remain poorly understood. This study addressed this gap using a mixed design (between-subjects and within-subjects) and a 2 × 2 × 2 factorial design to combine structural diversity, species richness and colour diversity of vegetation. Participants experienced virtual scenes created on Mars to assess preference and perceived restoration. Through analysis of variance (ANOVA), beneficial features of urban green space and formulated equations using a linear regression model to explain the joint effects of these characteristics were identified. Results indicate that rich structure, species and colours of vegetation significantly enhance preferences and perceived restoration, with colour having the greatest impact ─ 2.55 times greater than structural diversity and species richness. However, the superposition of multiple features does not mean ‘the more the merrier’, as binary and ternary interactions can have synergistic and erosive roles. Therefore, medium complexity is most beneficial for improving health and well-being. Overall, urban green space construction should consider multiple dimensions for a harmonious relationship between humans and nature, promoting sustainable development.

Integrated Transcriptome and Metabolome Analysis Revealed Mechanism Underlying Anthocyanin Biosynthesis During Flower Color Formation in Lagerstroemia indica

Lagerstroemia indica is a widely used ornamental woody plant known for its summer flowering and significant ornamental and economic value. While L. indica boasts a variety of rich flower colors, the molecular mechanisms underlying this color formation remain unclear. In this study, we selected three different flower colors of L. indica—white (W), red (R), and purple (P)—for transcriptome and metabolome analysis. The metabolome analysis identified 538 flavonoids, with 22 anthocyanins highly accumulated in the red and purple flowers. RNA-seq analysis annotated a total of 35,505 genes. Furthermore, we identified 42 differentially expressed genes (DEGs) involved in anthocyanin biosynthesis, with their expression levels aligning with anthocyanin content. Correlation analysis revealed that 19 MYB and 11 bHLH transcription factors are likely involved in anthocyanin biosynthesis. Additionally, we identified 59 auxin biosynthesis and signaling-related genes that are positively correlated with anthocyanin-related genes and metabolites, suggesting that auxin may play a role in regulating anthocyanin biosynthesis in L. indica. This study provides valuable insights into the regulatory mechanisms underlying anthocyanin accumulation and color formation in L. indica petals and identifies several potential genes, laying the groundwork for further research on regulatory mechanisms and genetic improvement of L. indica.

Identification of Floral Fragrance Components in 20 Intersectional Hybrids of Paeonia in Luoyang Region

ABSTRACTIntersectional hybrids of Paeonia (Paeonia Itoh hybrids) have rich colours and strong fragrance, combining the advantages of sect. Moutan and sect. Paeonia, and have great economic value and development potential. However, there have been few studies on the floral fragrance components of intersectional hybrids of Paeonia. In this study, the types and contents of volatile components of 20 intersectional hybrids of Paeonia were conducted. A total of 53 floral volatiles were identified though gas chromatography–mass spectrometry (GC–MS) analysis, with linalool, nonanal and phenylethyl alcohol as the main floral components. Based on the compound contents and odour activity values (OAVs) analysis, the 20 cultivars were classified into four aroma types: a floral scent, a fresh floral scent, a floral with spicy scent and a fruity scent. ‘Magical Mystery Tour’ had the highest volatile compound contents and OAVs, and had potential for exploitation. This study provided a theoretical reference for the selection of parents for flower fragrance breeding of Paeonia Itoh hybrids.

Nanocomposite Hydrogel Enables Color‐Gated Organic Photoelectrochemical Transistor Biodetection

AbstractThe newly emerged organic photoelectrochemical transistor (OPECT) has been demonstrated promising in diverse sectors, yet its underlying operation rationale remains largely unexplored due to its short development time. Color, arising from the light‐matter interactions, is ubiquitous in nature. Here the concept of color‐gated OPECT biodetection based on a nanocomposite hydrogel is proposed and devised, which is exemplified by the automatic color change of Pt nanocubes (NCs)‐encapsulated hydrogel with Ag+‐responsiveness. Linking with a sandwich immunorecognition with labeled silver nanoparticles (Ag NPs), chemical etching‐released Ag+ can sensitively affect the Pt NCs‐catalyzed conversion of o‐phenylenediamine, leading to the color change of the nanocomposite hydrogel and thus the altered gating characteristics. This study features the concept of color‐gated OPECT biodetection and is expected to catalyze a new category of advanced “colored” optobioelectronics, given the rich color change from the light‐matter‐bio interactions.

Hydroxypropyl Cellulose-Based Meter-Long Structurally Colored Fibers for Advanced Fabrics.

Structurally colored fibers are attractive alternatives to chemically colored fibers due to their rich optical properties, color stability, and environmental friendliness. However, the fabrication of structurally colored fibers using cost-effective raw materials with the possibility to scale up remains challenging. Here, a simple and scalable approach is developed to fabricate continuous meter-long structurally colored fibers exhibiting brilliant structural colors across the visible spectrum and helix orientation-dependent polarization states. The fibers are fabricated by extrusion of concentrated aqueous solutions of chemically crosslinked hydroxypropyl cellulose (HPC). The wavelengths and polarization states can be tuned by solution concentration, relaxation time, and collector's surface energy. The HPC-based structurally colored fibers display excellent optical stability to mechanical straining, repeated drying/water impregnation, and prolonged heating at 150°C. It is demonstrated that the HPC-based structurally colored fibers can be woven into structurally colored fabrics with wavelength- and polarization-coded optical patterns. The current work presents a strategy to tune the chiral nematic order, which constitutes an important step toward mass production of structurally colored fibers with stable and rich optical properties using easily available raw materials.

Conservation of Yuan Dynasty Caisson Paintings in the Puzhao Temple, Hancheng, Shaanxi Province, China

Caisson paintings are an integral part of the unique interior decoration ceiling of traditional Chinese architecture. There are a large number of Yuan Dynasty caisson paintings in the Puzhao Temple, in Hancheng, Shaanxi Province, China. These caisson paintings have exquisite patterns and rich colors, which are rare artistic treasures of the Yuan Dynasty. In the history of nearly 700 years, due to various environmental and human factors, the caisson paintings have experienced various degradation; for example, the paper of the caisson paintings is acidified, the surface is polluted, the color is faded, mottled, and it is difficult to identify. Therefore, their protection is vital. In order to ensure the scientific and targeted development of the protection scheme, this study conducted a comprehensive and in-depth analysis of the paper fibers, pigments, adhesives, wood supports, and pollutants of the caisson paintings and carried out a series of protection experiments in the field and laboratory, providing a step-by-step review of the protection treatment application for the caisson paintings. Mechanical and wet cleaning were used to remove the pollutants. The caisson painting was deacidified with a barium hydroxide ethanol solution, and the paper and pigments of the caisson painting were strengthened with water-based fluorine. Several conservation problems, such as the removal of pollutants, the deacidification of acidified paper, and the reinforcement of flaking paper and pigments, were solved. Meanwhile, good conservation and restoration results for caisson paintings were obtained. This research method of combining theory and practice has greatly improved the scientificity and success rate of conservation work. These research results provide valuable experience and reference for other caisson paintings in similar environments.

Graphene oxide dispersed rose-petals based green chemistry synthesis of hybrid composite for novel spectroscopic applications

Rosa Santana family includes the rose, a highly prized decorative plant having symbolic, cultural, and commercial value. The exploration of graphene-based nanocomposites has expanded significantly, with recent research focusing on integrating these materials into natural and sustainable matrices. This study investigates the dispersion of graphene oxide (GO) within the biological structure of rose-petals, representing a novel approach to developing eco-friendly nanocomposites. The rich colours of the roses are ascribed to pigments such as flavanols, carotenoids, and anthocyanin. Carotenoids, which are found in natural colours including yellow, orange, violet, as well as another ingredient found in rose petals. By leveraging the inherent properties of rose petals, such as their unique properties and surface morphology and biocompatibility, this work highlights the potential of GO to enhance the mechanical, electrical, and optical characteristics of the composite. Advanced characterization techniques, including scanning electron microscopy (SEM), and electrochemical analysis, are employed to understand the interaction between GO and the rose petal substrate. The techniques of FT-IR, EDS, XRD, SEM, energy band gap, and CV were used in characterize the synthesis of doped graphene using rose petals extract. The findings underscore the synergistic effects of this natural-synthetic hybrid system, opening pathways to innovative applications in flexible electronics, biosensors, and sustainable material design. The novelty of this research lies in its foundational exploration of integrating graphene oxide with organic substrates like rose petals, offering a new direction for the development of environmentally benign graphene nanocomposites. Green chemistry based novel nanocomposite may open up new avenues for production of graphene oxide homogenious dispersion with rose-petal extract.

Molecular mechanism of flower colour formation in Rhododendron simsii Planchon revealed by integration of microRNAome and RNAomics.

Systems-wide understanding of gene expression profile regulating flower colour formation in Rhododendron simsii Planchon is insufficient. In this research, integration analysis of ribonucleic acid (RNA)omics and microRNAome were performed to reveal the molecular mechanism of flower colour formation in three R. simsii varieties with red, pink and crimson flowers, respectively. Totally, 3129, 5755 and 5295differentially expressed gene (DEG)s were identified through comparative transcriptome analysis between 'Red variety' and 'Pink variety' (1507 up-regulated and 1622 down-regulated), 'Red variety' and 'Crimson variety' (2148 up-regulated 3607 down-regulated), as well as 'Pink variety' and 'Crimson variety' (2089 up-regulated and 3206 down-regulated), which were involved in processes of 'catalytic activity', 'binding', 'metabolic process' and 'cellular process', as well as pathways of 'metabolic pathways', 'biosynthesis of secondary metabolites', 'plant-pathogen interaction' and 'phenylpropanoid biosynthesis'. A total of 215 miRNAs, containing 153 known miRNAs belonging to 57 families and 62 novel miRNA, were involved in flower colour formation. In particular, 55 miRNAs were significantly differently expressed. Based on miRNA-mRNA regulatory network, ath-miR5658 could affect the synthesis of pelargonidin, cyanidin and delphinidin through downregulating accumulation of anthocyanidin 3-O-glucosyltransferase; ath-miR868-3p could regulate isoflavonoid biosynthesis through downregulating expression of CYP81E1/E7; ath-miR156g regulated the expression of flavonoid 3',5'-hydroxylase; and ath-miR829-5p regulated flavonol synthasein flavonoid biosynthesis process. This research will provide important roles in breeding new varieties with rich flower colour.

How to Make Flower Borders Benefit Public Emotional Health in Urban Green Space: A Perspective of Color Characteristics

The emotional health benefits of urban green space have been widely recognized. Flower borders, as a perennial plant landscape, have gradually become a current form of plant application in urban green spaces due to their rich color configurations. However, the related research primarily focuses on the impact of urban green spaces on public health, with relatively little attention given to how the colors of flower borders affect public emotional health. This study explored the relationship between the flower borders color characteristics and the public emotional health. In this study, 24 sample images were used as experimental materials, which selected based on their color richness and harmony. Additionally, face recognition technology and online random questionnaires were utilized to measure the public basic emotions and pleasure, respectively. The result shows that, based on the HSV color model and expert recommendations, 19 color characteristics were identified. The correlation analysis of the results from the public emotion with these color characteristics revealed that 13 color characteristics correlated with public emotional pleasure. Among them, blue, neutral purple, and low saturation were positively correlated. Through factor analysis, these thirteen color characteristics were summarized and categorized into four common factors (F1–F4), three of which are related to color. They are “low saturation of blue-violet percentage” (F1), “color configuration diversity” (F2), “bright red percentage” (F3), and “base green percentage” (F4), with F1 having the largest variance explained (27.88%). Finally, an evaluation model of color characteristics was constructed based on the variance explained by these four factors, which was demonstrated to effectively predict the level of public emotional pleasure when viewing flower borders. The results shed light on the effects of color characteristics on public emotions and provide new perspectives for subsequent flower border evaluations. Our results provide a valuable reference for future flower border color design, aiming to better improve public emotional health.

A dual-color ratiometric fluorescence sensor of biogenic amines with dye encapsulated covalent organic framework for meat freshness

Developing sensitive, nondestructive and real-time methods for assessing meat freshness is vital for ensuring food safety. Traditional monochromatic fluorescent probes for monitoring meat freshness markers like biogenic amines often face challenges in sensitivity, interference, visualization and portability for practical applications. Herein, we constructed a new Ru-Flu@COF fluorescence sensor, by combining a green fluorescent dye-encapsulated covalent organic framework (Flu@COF) with a red fluorescent compound (Ru (bpy)32+), exhibiting a dual inverse ratiometric fluorescence signal towards essential biogenic amines His and NH3·H2O, thus achieving a rich color gradient and spoilage-sensitive color discrimination. The detection linear range for His and NH3·H2O was 0.6–200 μM and 0.5–60 mg/L, with limits of detection of 0.5 μM and 0.2 mg/L, respectively. Furthermore, Ru-Flu@COF gel labels together with a smartphone enable portable, in situ and naked-eye monitoring freshness of pork, fish and shrimp, where the freshness level can be visually identified through the gel label color from red (fresh) to orange (less fresh), yellow (spoilage) and green (severe spoilage). The proposed smart label has the advantages of high sensitivity, excellent visual discrimination and portability, and it can be a promising platform for in situ nondestructive monitoring freshness of various kinds of meat for food safety inspection in the future.

Seasonal variations in psychophysiological stress recovery from street greenery: A virtual reality study on vegetation structures and configurations

The benefits of street greenery for well-being in urban development are widely recognized. However, few studies have explored seasonal variations in the psychophysiological stress recovery effects of different street greenery. To address this gap, we conducted field research in the Guanzhong region of China and created virtual streetscapes representing different seasons using Mars 2020 software. This study categorized vegetation into various layers based on their biological attributes: deciduous and evergreen trees for the arbor layer, evergreen and colourful foliage hedges for the shrub layer, observable and unobservable flowering herbs for the herb layer. They were then classified into Tree, Tree-Shrub, Tree-Herb, and Tree-Shrub-Herb structures, all of which had different seasons and vegetation configurations. 1,136 participants were recorded for psychophysiological changes in different street greenery virtual reality scenarios. The results were as follows: 1. Streets with greenery exhibited greater stress recovery effects than those without greenery. Seasonally, the physiological stress recovery effects were greater in autumn and winter, and there was an interaction between season, structure, configuration factors. 2. Overall, the Tree-Shrub structure was most effective for stress recovery, the Tree-Shrub-Herb structure was least effective. However, the Tree-Shrub-Herb structure proved to be the best in winter. 3. Rich color and stable green coverage were most effective for improving psychological and physiological stress recovery, respectively. However, the optimal vegetation types and configurations for stress recovery vary with specific viewing periods within each season. These findings offer a theoretical foundation and practical reference for designing health-oriented street greenery and seasonal landscapes in future.

Electrochromic behaviors and applications of tetrasubstituted thienoviologen derivatives

Electrochromic materials have been widely used in various parts of life due to their advantages of energy conservation and rich colors. In this work, a series of novel viologen derivatives (tetrasubstituted thienoviologen derivatives, a–f) were designed and synthesized as electrochromic materials by decorating 4,4′,4″,4‴-(thiophene-2,3,4,5-tetrayl)tetrapyridine with different N-substituents (alkyl, benzyl and aryl). Electrochromic devices based on a–f exhibited a low working voltage of −1.4 V. The N-substituents markedly affected their electrochromic performance. The compounds with alkyl and benzyl substituents performed better than the compound with aryl substituent. Among them, compound c with benzyl substituent performed best with a high optical contrast (66 %), a high coloration efficiency (389 cm2/C), good cycling stability, and fast response time. Besides, compound c was also applicable to sodium carboxymethyl cellulose hydrogel ECD with good cycling stability and a broad absorption band (500–700 nm) in the visible region. The applications of compound c in electronic tags, functional displays and smart windows were explored, indicating it's a promising ECM with wide application prospects.

Selection and Validation of Reliable Reference Genes for Liquidambar formosana Leaves with Different Leaf Colors.

Liquidambar formosana Hance is renowned for its rich leaf color and possesses notable advantages, such as robust adaptability, strong resistance to diseases and pests, and rapid growth, making it a preferred choice for urban greening and carbon sequestration forest initiatives. The completion of whole-genome sequencing of L. formosana has spurred an increased interest in exploring the molecular mechanisms underlying seasonal changes in leaf color, marking a significant focus in L. formosana breeding research. However, there is currently a lack of stable reference genes suitable for analyzing the expression patterns of functional genes in L. formosana exhibiting varying leaf colors. This study selected five L. formosana varieties with significant differences in leaf colors. Through the RT-qPCR analysis, and evaluation using BestKeeper, geNorm, NormFinder, Delta Ct, and RefFinder, the expression stability of 14 candidate reference genes was examined. Consequently, two reference genes (LifEF1-α and LifACT) with stable expression, suitable for RT-qPCR of L. formosana with diverse leaf colors, were identified. The stability of these selected reference genes was further validated by examining the LifbHLH137 gene, which promoted the biosynthesis of anthocyanins. This advancement facilitated molecular biology and genetic breeding investigations of L. formosana, providing essential data for the precise quantification of functional genes associated with leaf color variation.