Dark Blue Color Research Articles

Carbazole-Based Dual-Band Electrochromic Polymers: The Effect of Linkage Sites on Electrochromic Performance.

Dual-band electrochromic (EC) materials are expected to be utilized as building materials for energy saving, but their cycle stability is still an obstacle. Here, two D-A conjugated polymers, PDPPCz36 and PDPPCz27, based on diketopyrrolopyrrole and carbazole linked with different sites, are synthesized. Both of them exhibit dual-band EC behaviors with a dark blue color in the neutral state and high absorption in the near-infrared (NIR) region when oxidized. However, PDPPCz36 exhibits better cycle stability and a shorter response time than PDPPCz27. In the visible (VIS) region, the PDPPCz36 film exhibits an initial light modulation range (ΔT) of 43.0% and that of the PDPPCz27 film is 41.3%. After 100 cycles of redox, the ΔT of the PDPPCz36 film declines by 32%, while that of PDPPCz27 attenuates by more than 50%. A similar tendency is evident in the NIR region. Moreover, PDPPCz36 shows subsecond colored switch times both in the VIS (0.4 s) and NIR (0.7 s) regions, while those of PDPPCz27 are 2.1 and 1.6 s, respectively. Further research suggests that 3,6-linked carbazoles in PDPPCz36 simultaneously inhibit the side reaction and film aggregation, which leads to better redox stability and shorter response time in both EC tests and devices.

Predicting landslide extent of satellite images based on image classification extraction

Abstract Landslide is a common geological disaster and the most destructive natural disaster at home and abroad. Therefore, automatic interpretation of landslide high-risk areas and potential landslide areas through different models and methods is one of the basic ways to prevent and reduce possible disasters. In this study, we improve the NDWI method by using the multispectral image data from the French satellite SPOT 5. Combined with infrared band sensors, the Normalized Difference Water Index (NDWI) of large exposed landslides is extracted by improving the NDWI index method by utilizing the characteristics of near-infrared (NIR) and short-wave infrared (SWIR) bands and replacing the green-wave band or the mid-infrared (MIR) band with the short-wave infrared (SWIR) band, which can be applied to the water resources management of high-risk areas, potential landslide areas, and potential landslide areas, and the water environment monitoring of water resources and disaster emergency management. We calculate the 2014 satellite images with a total area of 11351.6 ha, and after the NDWI index, the dark blue color represents the high-risk landslide area of 1609.1 ha (14175%), the light blue color represents the potential landslide area of 3971.773 ha (34.989%), and the brown color represents the vegetation area of 5770.727 ha (50.836%).

The Potential of Transforming Growth Factor-Beta1 (TGFβ1) in Fibrotic Tissue of Leiomyoma Specimens

Background: Fibrosis can define as the development of excessive fibrous tissue in an organ or tissue. In the situation of the uterus, leiomyoma or scar tissue may involve fibrosis state. The main feature of fibrosis in myoma is the existence of disordered smooth muscle cells and collagen that can be recognized via histological examinations in addition to extracellular component deposition. Leiomyoma is the most public uterine disorder that is mainly consists of smooth muscle cells, myo-fibroblast, and an obvious content of extracellular matrix. The myofibroblast in myoma lesion produced an elevated content of ECM. This paper displays the fibrotic circumstantial in leiomyoma and the mechanisms related to deposition of ECM components. Methods: this study involved (50) patients of 18-80 years old women diagnosed with benign uterine fibroid. Tumor samples were attained by consent from women undergoing hysterectomy or myomectomy at the Al Karama Teaching Hospitals in Kut, Wasit Province, Iraq between October 2022 to March 2023. samples from normal and fibroid were subjected to routein histological processing and subsequently stained with routein stains for general description, Masson Trichrome stain, Van Gieson's stain to visualize collagen content and histochemical stain (Alcian Blue-Periodic Acid Schiff) to evaluate the profile of mucins secreted via tumor cells.Normal myometrium and myoma tissue expression of TGF β1 growth factor was compared using immunohistochemical staining. Qupath and Image J programs were used to analysis the content of fibrous tissue within normal and myoma tissue. Results: Microscopical results revealed that myoma have a proliferation of overlap fusiform cells organized in bundles alienated by variable amounts of connective tissue fibers, enclosed peripherally by a pseudo capsule. Special stained sections analysis revealed deposition of extracellular martix components specially collagen fibers that vary within each nodular fibroid (intrafascicular, interfascicular) enclosed myocytes that reflect the state of fibrosis that appears as blue – green colors enclosed in Masson's trichrome stain, while in Van Gieson's stain appears as red color. Proliferative tumor cells were revealed via Alcian Blue-PAS stain in dark blue color. results showed distribution of perivascular fibers in myoma as compared with normal adjacent myometrium, which appears in red color in Van Gieson's stain. Immunostaining recorded the significantly higher intensity of TGF-β in the leiomyoma tissue than in the normal myometrium (P < 0.05). The effects of the TGF-β1 inhibitor significantly differed between normal myometrium and leiomyoma tissue, with a greater decrease in cell survival in the leiomyoma tissue (P < 0.05). Conclusion: highly fibrous tissue contents showed within myoma and perivascular than adjacent myometrium, these fibrous tissues were detected via special colours in both Masson Trichrome and Van Gieson's stains. The fibrous tissue within leiomyoma showed higher intensity to TGF than normal myometrium.

A Network of Circular RNA and MicroRNA Sequencing Provides Insights into Pigment Deposition of Changshun Blue Eggshell Chickens.

Eggshell color plays important biological roles and attracts the attention of both egg retailers and researchers. However, whether non-coding RNAs are involved in pigment deposition among different eggshell colors remains unknown. In this study, RNA sequencing was used to analyse the uterine gland transcriptome (CircRNA and miRNA) of Changshun chicken blue-shell hens producing four different eggshell color eggs including dark blue PK(DB) and light blue (LB), dark brown and greenish (between blue and pink, DP) and pink (p). We found that miR-192-x, targeting SLC16a7, was expressed in DB, DP, and LB groups compared with the PK group, which indicates that miR-192-x may play a role in the blue eggshell color. KEGG and GO analyses showed that the "metabolic pathways" with targeted genes such BLVRA and HMOX1 were detected in dark and light blue color eggshell chickens, which confirms the different ratios of biliverdin and HO-1 involved in the deposition of blue color. As annotated by connectivity analysis, RASGRF1 and RASGRF2, belonging to the RASGRF family, are involved in the Ras signaling pathway, which plays an important role in cell growth, differentiation, metastasis and apoptosis. Our findings enrich the database of circRNA, miRNAs and genes for chicken uterine tissue, which will be useful in accelerating molecular selection for blue eggshell color layers.

Insights into the mechanism of color formation of the freshwater prawn (Macrobrachium rosenbergii) revealed by de novo assembly transcriptome analysis

Body color is an important visual indicator of crustacean quality and plays a major role in consumer acceptability, perceived quality, and the market price of crustaceans. The freshwater prawn (Macrobrachium rosenbergii) has two distinct phenotypic variations, characterized by dark blue and light yellow body colors. However, the underlying mechanisms regulating the body color of M. rosenbergii remain unclear. In this study, the composition of shell color parameters and pigment cells of raw and cooked dark blue and light yellow M. rosenbergii was investigated and the mechanisms associated with body color were elucidated by transcriptome analysis. The results showed significant differences in the raw shells of the dark blue and light yellow M. rosenbergii (L: 26.20 ± 0.53 vs. 29.25 ± 0.45; a: −0.88 ± 0.19 vs. 0.35 ± 0.18; b: 1.73 ± 0.20 vs. 3.46 ± 0.37; dE: 70.33 ± 0.53 vs. 67.34 ± 0.45, respectively, p = 0.000) as well as the cooked shells (L: 58.14 ± 0.81 vs. 55.78 ± 0.55; a: 19.30 ± 0.56 vs. 16.42 ± 0.40; b: 23.60 ± 0.66 vs. 20.30 ± 0.40, respectively, p < 0.05). Transcriptome differential gene analysis obtained 39.02 Gb of raw data and 158,026 unigenes. Comprehensive searches of the SwissProt, Nr, KEGG, Pfam, and KOG databases resulted in successful annotations of 23,902 (33 %), 40,436 (25.59 %), 32,015 (20.26 %), 26,139 (16.54 %), and 22,155 (14.02 %) proteins, respectively. By KEGG pathway analysis, numerous differentially expressed genes were related to pigmentation-related pathways (MAPK signaling pathway, Wnt signaling pathway, melanin production, tyrosine metabolism, and cell-cell communication process). Candidate DEGs that may be involved in body color included apolipoprotein D, crustacyanin, cytochrome P450, and tyrosinase, as verified by quantitative real-time PCR. The results of this study provide useful references to further elucidate the molecular mechanisms of color formation of M. rosenbergii and other crustaceans.

Near-infrared reflective Mg0.5Co0.5-xMnxAl2O4 black pigment synthesized by spray pyrolysis: Optimization of composition and calcination temperature

Co/Mn co-substituted MgAl2O4 pigments were spray pyrolysis, and their crystal structure and optical properties were characterized with changing the Co/Mn ratio and synthesis temperature. Regardless of the Co/Mn ratio, the resulting pigments showed spinel structured MgAl2O4 phase without any impurity phase. The synthesized Mg0.5Co0.5Al2O4 and Mg0.5Mn0.5Al2O4 showed a dark blue and brown color due to the visible light absorption by the 4A2(F) → 4T1(P) transition of Co2+ and the d-d transition of Mn2+, respectively. The black colored pigment was achieved by simultaneous substituting Co2+ and Mn2+ in the Mg2+ tetrahedral site in MgAl2O4. The optical band gap of the Mg0.5Co0.5-xMnxAl2O4 pigment decreased linearly from 3.08 eV (x = 0) to 2.46 eV (x = 0.4) as the Mn2+ content increased. As a result, Mg0.5Co0.1Mn0.4Al2O4 uniformly absorbed the entire visible light and had a black color (L* = 28.10, C* = 1.68). In terms of obtaining high near-infrared reflectance and good blackness, the optimal calcination temperature of Mg0.5Co0.1Mn0.4Al2O4 was determined to be 900 °C. The optimized Mg0.5Co0.1Mn0.4Al2O4 black pigment had a good LiDAR reflectance (38 % at 905 nm) and excellent chemical stability, and showed improved heat shielding performance compared to carbon black using in black vehicles.

Multienzyme cascades analysis of α-glucosidase by oxygen deficient MoO3-x

BackgroundRecently, the enzymatic cascade reactions during the cellular process are widely used for fabricating robust biosensors and they have attracted extensive attention in analyzing various clinical biomarkers. The enzymatic cascades analysis is commonly based on the peroxidase (POD)/oxidase coupled system. However, the requirement of harsh acidic environment, poor stability and interference from the oxidase further limit their analytical practicability. Herein, novel chromogenic nanomaterials with H2O2 sensitive features are urgently required to replace the POD nanozyme in enzymatic cascades based bioanalysis. ResultsHerein, oxygen deficient MoO3-x with H2O2 sensitive features and near-infrared (NIR) absorption band have been ultra-fast synthesized and utilized for the enzymatic cascades analysis of α-Glucosidase's activity, and inhibitors screening. With the addition of 4-nitrophenyl-α-d-glucopyranoside, the simultaneous presence of α-Glucosidase and glucose oxidase (GOx) would fade their dark blue color and decrease the NIR absorption. The α-Glucosidase's activity can be analyzed by the absorption at 770 nm, and their limit of detection is 8 × 10−5 U/mL, indicating the superior performance of the proposed colorimetric assay. Moreover, this proposed α-Glucosidase assay is further utilized for inhibitors screening. Moreover, the activity of α-Glucosidase can also be analyzed by the smartphone and microplate reader through the agarose-based colorimetric portable kit. SignificanceThis MoO3-x involved enzymatic cascades assay would facilitate for the development of bio-analysis related to H2O2 generation or consumption. Moreover, this bio-analysis strategy will contribute to the development of other H2O2 sensitive chromogenic nanomaterials for the analysis of certain biomolecules and biological enzymes.

Thermochromism and thermal crystal structure evolution of YIn0.9Mn0.1O3

YIn1-x Mn x O3 is a newly discovered inorganic blue pigment whose vivid blue color results from MnO5 trigonal bipyramidal (TBP) polyhedra. Recently, it has been reported that commercial YIn1-x Mn x O3 powders exhibit a temperature-induced color change, i.e. thermochromism. In this study, we investigate the thermochromism and temperature-induced crystal structure evolution of synthetic YIn0.9Mn0.1O3 powders. We observe that a vivid blue color at RT gradually changed to a dark blue color with increasing temperature. This thermochromism is mainly attributed to a broadening of optical absorption bands in the visible and UV regions, and can also be contributed to by an enhancement of the UV absorption. Our crystal structure analysis using powder synchrotron X-ray diffraction data not only confirms the thermal expansion and enhanced thermal vibrations of oxygen, but also reveals a temperature-induced deformation of the TBP polyhedra. Based on these results, we discuss a possible mechanism for the thermochromism of the YIn0.9Mn0.1O3 system.

Photocatalytic Activity and Electron Storage Capability of TiO2 Aerogels with Adjustable Surface Area

Nanostructuring of semiconductor photocatalysts is one important strategy to improve photocatalytic activities. An interesting nanostructuring strategy is the generation of mesoporosity, i.e. in aerogels. Aerogels are 3D nanostructures of interconnected porous networks with enormous porosity, ultra-low density, and high surface areas, which are higher than surface areas of particle systems.[1,2] The high surface area and presumably high amount of reactive sites and a good contact of the active material to the electrolyte, as well as short diffusion pathways for the minority charge carriers and an improved charge carrier separation are advantageous for photocatalytic applications.[3-5]TiO2 aerogels offer a higher density of photoexcited electrons compared to TiO2 nanoparticles.[5] Electrons in TiO2 are trapped close to the surface of the material and Ti3+ states are formed, which show a characteristic dark blue coloration, i.e. a broad absorption at a maximum of 650 nm.[6-8] Stored photoexcited electrons in TiO2 can be used for different dark reduction reactions.[7-10] A very promising reduction reaction using such stored photoexcited electrons is the nitrogen reduction reaction for the production of ammonia, which was first reported by Bahnemann et al. in 2011 for stored electrons in TiO2.[8] This reaction can pave the way to an energy efficient and decentralized production of ammonia, which is commonly produced via the extremely energy intensive Haber-Bosch process, which causes 2 % of the annual global energy consumption and 1.6 % of the global CO2 emissions.[11]Herein, we present the photocatalytic hydrogen evolution activity and electron storage capability of mesoporous TiO2 aerogels which were prepared via a novel acid-catalyzed sol-gel synthesis with subsequent supercritical drying.[12] The as-synthesized aerogel provided a surface area of 600 m2 g-1 which could be tailored by different heat treatments. The sacrificial hydrogen evolution activity of the aerogels decreased with increasing surface area and decreasing crystallinity. At the same time, the addition of an aqueous H2PtCl6 solution to the bluish dispersions in the dark resulted in the evolution of hydrogen without light irradiation, due to the reduction of Pt4+ to Pt0 and the formation of a Schottky contact. The intensity of that dark hydrogen evolution peak increased with increasing surface area. This reduction reaction could be used to quantify the amount of electrons stored in the aerogels. Furthermore, it could be shown that the electron storage capability depends on the hole acceptor concentration. The ability to reduce nitrogen to ammonia in the dark with the stored photoexcited electrons in such an aerogel will be presented. These results pave the way for future research on the optimization of aerogel properties depending on their future application together with optimization of photocatalytic nitrogen reduction and other reduction reactions with such aerogels.[1] S. Alwin et al. Mater. Renew. Sustain. Energy 2020, 9, 7[2] N. Hüsing et al. Angew. Chemie Int. Ed. 1998, 37, 22[3] M. L. Anderson et al. Adv. Eng. Mater. 2000, 2, 481[4] P. A. DeSario et al. J. Phys. Chem. C 2015, 119, 17529[5] D. A. Panayotov et al. J. Phys. Chem. C 2013, 117, 15035[6] D. Bahnemann et al. J. Phys. Chem. 1984, 88, 709[7] H. H. Mohamed et al. J. Phys. Chem. A 2011, 115, 2139[8] H. H. Mohamed et al. Chem. - A Eur. J. 2012, 18, 4314[9] H. H. Mohamed et al. J. Photochem. Photobiol. A Chem. 2011, 217, 271[10] H. H. Mohamed et al. J. Photochem. Photobiol. A Chem. 2012, 245, 9[11] K. Wang et al. Carbon Resour. Convers. 2018, 1, 2[12] A. Rose et al. ACS Appl. Energy Mater. 2022, 5, 14966

Tunable assembly of Ferric ion-dopamine molecules into hedgehog-like nanozyme for colorimetric and sensitive detection of acrylamide in thermally processed foods

The ferric ion-polydopamine coordination hedgehog-like superstructure (hedgehog-like Fe-PHS) was fabricated using the metal–ligand crosslinking strategy, which was used as a colorimetric sensor for acrylamide (AA) visual detection. The hedgehog-like Fe-PHS exhibited outstanding peroxidase-like activity toward the decomposition of H2O2 and production of hydroxyl radical (OH), and oxidized colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to blue oxTMB. The TMB oxidation was quenched by glutathione and then recovered via a thiol-ene Michael addition reaction between glutathione and AA. The increase in AA concentrations accelerated the TMB oxidation and recovered the dark blue color. Thus, the hedgehog-like Fe-PHS was used as a colorimetric sensor for detecting AA. A wide linear range from 0.75 to 36.00 µM (R2 = 0.9950) and a low limit of detection of 0.27 µM with excellent selectivity were obtained. AA was visually detected with “naked eye” using hedgehog-like Fe-PHS. Meanwhile, the hedgehog-like Fe-PHS colorimetric sensor was successfully applied for detecting AA in thermally processed foods, and its practical feasibility was verified using the HPLC method.

Four new saproxylic species of Paranura Axelson, 1902 (Collembola: Neanuridae: Neanurinae) from Japan.

Four new saproxylic species of the genus Paranura from Nagasaki, Nara, and Niigata provinces of Japan are described and illustrated in this paper. Paranura tsushimaensis sp. nov. is characterized by a dark blue body color, Abd. V four times as long as Abd. VI, 3+3 eyes, three ocular chaetae on the head, four ordinary chaetae De on Th. III, two ordinary chaetae Di on Abd. V, and all dorsal chaetae of Abd. VI in a unique reticulated plate. P. nakamurai sp. nov. is identified by its yellowish white body color, 2+2 eyes, tubercle Af on the head with two reticulated tubercles, and tubercles Di on Abd. V fused. P. alpicola sp. nov. is characterized by its yellow body color, 3+3 eyes, presence of complete chaetotaxy in the central area of the head, Th. IIIII with two and three ordinary chaetae De respectively, and tubercles Di on Abd. V separate. P. convallis sp. nov. is identified by its orange body color, 3+3 eyes, head without chaeta O, three mandibular teeth, and Th. IIIII with three and four ordinary chaetae De respectively. A key for all species of the genus Paranura is provided.

Enrichment of meat products with natural bioprotectors and antioxidants

In the course of scientific research the chemical composition, physico-chemical and antioxidant properties of local grape and secondary raw materials of winemaking industry were studied, the technology of sausage production with the addition of grape extract of high nutritional value was substantiated and developed. Information on the antioxidant activity of grape raw materials growing in the territory of the Republic of Bashkortostan has been obtained. The presence of biologically active substances with antioxidant and antioxidant properties in the grape extract is a promising factor for the introduction of the extract in food products, including meat products, to enrich them with antioxidants. Analyzing the results of the study, we can conclude that the use of 3% grape squeeze extract will enrich meat products with a sufficient amount of antioxidants of natural plant origin. In the course of research it was found that the extract from grape squeeze has a rich dark blue color due to the high content of anthocyanins, which can affect the organoleptic characteristics of the finished meat product, in connection with that the color characteristics of the minced meat samples were analyzed. An important indicator in our scientific research was the preservation of antioxidants in the process of preparation of the extract and introduction into the minced meat. In this regard, the degree of preservation of calculated and actual total content of antioxidants in different objects was further studied. The technology of obtaining new types of food products - sausages, based on the use of grape extracts has been scientifically substantiated. It has been established that within the framework of the modern theory of positive nutrition it is more reasonable to add grape squeeze extract instead of fatty meat raw materials. This allows to enrich sausage products not only with mineral substances, organic and polyunsaturated fatty acids, vitamins, amino acids, pectin substances, but also to obtain biologically valuable meat products based on secondary grape raw materials.

НАУЧНЫЙ АНАЛИЗ ФИОЛЕТОВОГО ВОСЬМИУГОЛЬНОГО СТОЛБЧАТОГО ИЗДЕЛИЯ, НАЙДЕННОГО НА МОГИЛЬНИКЕ ХЭЦЗЯ, СЯНЬЯН, ШЭНЬСИ, И СВЯЗАННЫЕ С ЭТИМ ВОПРОСЫ

In this paper, we chose late war purple octagonal prismatic ware excavated at the Hejia Cemetery in Xianyang as the object of study, and carried out scientific analysis using ultra-deep field microscopy, scanning electron microscopy and energy spectrum analysis, X-ray diffraction, and microscopic Raman spectroscopy. First of all, the features of the formation and weathering process were determined, then the samples of unweathered areas obtained by the sectioning method were examined, and it was confirmed that all 12 samples are barium copper silicate with the main phases of Chinese violet (BaCuSi2O6) and Chinese dark blue (BaCu2Si2O7) colors. Based on compositional characteristics, etc. it was also found that this group of purple octagonal vessels embodies two different manufacturing processes and may represent an evolution of the process from lead-barium glass to cupro-barium silicate. On this basis, issues such as the population, distribution area and functional characteristics of this type of dish are discussed in order to obtain new ideas and evidence for relevant research.

High-performance black electrochromic devices using benzothiadiazole viologen and trisaminocyclopropenium perchlorate with extremely low transmittance and good stability

To minimize the colored state transmittance of the device in the ultraviolet–visible (UV–Vis) region (300–800 nm), we applied the idea of spectral complementary absorption to design electrochromic devices with transparent to black transition. Benzothiadiazole viologen (BV) and trisaminocyclopropenium ions (TAC) organic materials with dark blue and red coloration states were selected to prepare electrochromic devices with extremely low transmittance, here TAC is used as electrochromic material for the first time. The electrochromic devices do not require any supporting electrolytes. By controlling the concentration ratio of two materials, we achieved the ultra-low transmittance (0.33%), extremely low relative luminance (%YL = 0.12%), and fairly high coloring efficiency (341.9 cm2/C) of the TB-1 (0.05 mol/L TAC, 0.05 mol/L BV) device. Meanwhile, the TB-2 (0.0375 mol/L TAC, 0.05 mol/L BV) device possesses high transmittance contrast (81.79%) and very good long-cycle stability (4000 cycles, 96.1%).

Phthalocyanine-Blue Nanoparticles for the Direct Visualization of Tumors with White Light Illumination.

The current standard of care for colon cancer surveillance relies heavily on white light endoscopy (WLE). However, dysplastic lesions that are not visible to the naked eye are often missed when conventional WLE equipment is used. Although dye-based chromoendoscopy shows promise, current dyes cannot delineate tumor tissues from surrounding healthy tissues accurately. The goal of the present study was to screen various phthalocyanine (PC) dye-loaded micelles for their ability to improve the direct visualization of tumor tissues under white light following intravenous administration. Zinc PC (tetra-tert-butyl)-loaded micelles were identified as the optimal formulation. Their accumulation within syngeneic breast tumors led the tumors to turn dark blue in color, making them clearly visible to the naked eye. These micelles were similarly able to turn spontaneous colorectal adenomas in Apc+/Min mice a dark blue color for easy identification and could enable clinicians to more effectively detect and remove colonic polyps.

Effect of acid and alkaline treatment on the adsorption capacity of cuttlefish bone

As a center of textile industry in Indonesia, city of Pekalongan faces environmental issue due to wastewater effluent from textile industry. The wastewater from textile industry contains dye, mostly synthetic dye, used for coloring the fabrics. One of the dyes commonly used is sulphur blue for producing dark blue color. One of simple methods to reduce the dye in the wastewater is adsorption. Cuttlefish bone was used as the adsorbent. It is abundantly available and cheap because it is a waste of fishing industry. The effect of acid and alkaline treatment to the cuttlefish bone on its adsorption capacity toward sulphur blue dye was investigated. The acid and alkaline treatments were conducted using hydrochloric and sodium hydrochloric solutions, respectively. The concentrations of both solutions were varied (0.0 N, 0.25 N, 0.5 N, 0.75 N, 1.0 N). The concentration of acid and alkaline affect the adsorption capacity of the cuttlefish bone. The cuttlefish bone treated with 0.25 N hydrochloric solution is able to reduce the concentration of the dye solution from 217.67 to 87.67 Pt-Co, while that treated with 0.25N sodium hydroxide solution lowers the concentration of the dye solution to 74.33 Pt-Co. The alkaline-treated cuttlefish bone showed higher adsorption capacity than the acid-treated cuttlefish bone.

Band-gap alteration of Zn2SnO4 nanostructures for optical and photo-luminescent applications

Present manuscript reports the hydrothermal synthesis of pristine (Zn2SnO4) and copper doped Zn2SnO4 spinals under subcritical conditions. XRD pattern identifies the cubic phase of pristine and its doped nanostructures. Tauc plot and density functional theory (DFT) studies claim the lowering of band gap values up to 2.5 eV upon the insertion of transition metal copper (Cu) into the host lattice. Blue shift occurs due to Moss−Burstein effect upon excess concentration of Copper is realized. Both pristine and Cu doped Zn2SnO4 present light green and dark blue colour upon the irradiation of different UV (252 nm and 365 nm) lamps, respectively. Besides this, Zn2SnO4 shows effectiveness in hosting Cu ions, thus could act as a prospective green/blue emitter.

Physical characterization of genipin complexes coupled with multivariate data analysis to assess formed pigments

The potential of electrophoretic mobility and dynamic light scattering (DLS) was investigated to assess pigment formation in aqueous solution after the genipin reaction with different amino acids by separate. Absorbance, mobility, hydrodynamic size, polydispersity index, and conductivity of the aqueous solutions were measured after the reaction. Only complexes derived from genipin and leucine, tyrosine, arginine, lysine, and glycine developed dark blue colors. From all measured variables, complex size was correlated with their blue color intensity, and darkest blue complexes showed the highest hydrodynamic size (1073–4179 nm). Moreover, size pigments below 1 µm were obtained for all amino acids at different concentrations of genipin and amino acid, except for arginine. A partial least squares (PLS) model for size was built and exhibited a good ability to describe the distribution in blue complexes formed after the reaction of genipin and excess of amino acid (mM): (R2adj = 0.88; RMSE = 0.94). Electrophoretic mobility and DLS coupled with multivariate analysis is a useful tool as it can give reliable assessment of the physical properties of aqueous solutions of genipin pigments.

Absence of near-ambient superconductivity in LuH2±xNy

A recent study demonstrated near-ambient superconductivity in nitrogen-doped lutetium hydride1. This stimulated a worldwide interest in exploring room-temperature superconductivity at low pressures. Here, by using a high-pressure and high-temperature synthesis technique, we have obtained nitrogen-doped lutetium hydride (LuH2±xNy), which has a dark-blue colour and a structure with the space group Fmbar{3}m as evidenced by X-ray diffraction. This structure is the same as that reported in ref. 1, with a slight difference in lattice constant. Raman spectroscopy of our samples also showed patterns similar to those observed in ref. 1. Energy-dispersive X-ray spectroscopy confirmed the presence of nitrogen in the samples. We observed a metallic behaviour from 350 K to 2 K at ambient pressure. On applying pressures from 2.1 GPa to 41 GPa, we observed a gradual colour change from dark blue to violet to pink-red. By measuring the resistance at pressures ranging from 0.4 GPa to 40.1 GPa, we observed a progressively improved metallic behaviour; however, superconductivity was not observed above 2 K. Temperature dependence of magnetization at high pressure shows a very weak positive signal between 100 K and 320 K, and the magnetization increases with an increase in magnetic field at 100 K. All of these are not expected for superconductivity above 100 K. Thus, we conclude the absence of near-ambient superconductivity in this nitrogen-doped lutetium hydride at pressures below 40.1 GPa.

Effect of Hyper-Cross-Linking on the Electrochromic Device Properties of Cross-Linkable Carbazole–Diphenylamine Derivatives

Triphenylamine derivatives are promising organic electrochromic (EC) materials due to their easy synthesis, low oxidation potentials, high charge-carrier mobilities, electrochemical stability, coloration efficiency, and tunability of EC properties via substitution. Further, the cross-linking strategy provides an added advantage to the small-molecule-based EC devices in terms of better-quality EC films with enhanced EC properties. Herein, we discuss the EC properties of two carbazole–diphenylamine derivatives, C-Sty2 and C-Sty3, with two and three thermally cross-linkable styryl units, respectively, following a donor−π–donor (D−π–D) design, where both the carbazole moiety and cross-linking styrene groups modulate the photophysical and EC properties. Both styryl derivatives formed rigid, uniform, and transparent films with high solvent resistance and exhibited excellent thermal and electrochemical stability upon cross-linking. C-Sty3, with three cross-linkable styryl units, could form more extended cross-links, leading to hyper-cross-linked films with distinct, regular, and porous morphology compared to C-Sty2. Spectroelectrochemical studies of the films showed a color change from a transparent colorless state to an initial light-yellow color and then a final dark-blue color with a color contrast of 65% at 890 nm for C-Sty2 and 78% at 850 nm for C-Sty3. The hyper-cross-linked films of C-Sty3 demonstrated enhanced coloration efficiency (248 cm2/C), optical contrast, and open-circuit memory compared to C-Sty2. Electrochemical impedance spectroscopy analysis showed lower solution and charge-transfer resistances (Rs and Rct, respectively) for hyper-cross-linked films of C-Sty3, indicating higher conductivity and ion diffusion compared to C-Sty2. Thus, a comparison of the EC properties of two polymers with the same electroactive groups reveals the significance of hyper-cross-linking in the EC properties of these cross-linked polymers. Furthermore, the EC properties of the hyper-cross-linked D−π–D derivative, C-Sty3, were compared to those of previously reported molecules, demonstrating the importance of highly branched conducting polymers for EC applications.