Search Results (12)

The management of invasive alien species (IAS) generates large amounts of plant waste biomass that is commonly disposed of by burning or destruction, leading to environmental and economic drawbacks. At the same time, the production of synthetic dyes and pigments used in printing and graphic applications remains a significant source of pollution. In this context, the valorization of IAS biomass as a source of natural colorants represents a sustainable alternative aligned with circular economy principles. Here, biocompounds and natural dyes were extracted from four invasive or non-native plant species—Arundo donax, Phytolacca americana, Tradescantia fluminensis, and Eucalyptus globulus—using five solid–liquid extraction methods: infusion, infusion with heat, thermal agitation, Soxhlet extraction, and ultrasonic-assisted extraction. Extraction efficiency and color preservation were comparatively evaluated. Although Soxhlet extraction provided the highest extraction yield (up to 30.5%), infusion with heat proved to be the most suitable method for preserving color integrity and minimizing oxidation. Liquid dyes obtained by the selected extraction method were converted into solid pigments through a lake pigment precipitation process using aluminum potassium sulfate and sodium bicarbonate. The resulting pigments were characterized in terms of chemical composition, particle size, and chromatic properties, and subsequently formulated into oil-based inks using linseed oil as binder. Scanning electron microscopy revealed pigment particle sizes ranging from approximately 2.1 to 8.3 µm, depending on the plant source, and confirmed adequate ink penetration and distribution on commercial printmaking paper. The obtained pigments exhibited color tones ranging from yellow to brown and grey, mainly associated with the phenolic and tannin content of the original biomass. Printing tests demonstrated the suitability of the developed inks for manual printmaking techniques, highlighting the potential of IAS-derived pigments as sustainable alternatives for artistic and printing applications. Full article

Properties of surface anchoring depend on the absorbed exposure energy and various potential interactions associated with liquid crystal and azo dye layers. In this study, we investigate a model of dispersion, steric and photoinduced interactions with the goal of providing a qualitative and quantitative description of orientationally ordered hard uniaxial liquid crystals and azo dye molecules. By using the Onsager theory, we estimated the effect of excluded volume. Typical repulsive potentials between liquid crystal and azo dye molecules are displayed graphically. The presence of statistical dispersion in molecular alignment of liquid crystals leads to potential wells in dipole–dipole interactions. Our mean field theory investigation of dipole–dipole interactions shows that the anchoring free energy is governed by the net interaction energy associated with the averaged dipole moments of liquid crystal and azo dye molecules, photoaligned surface dipole moments, and local charge densities. We also use the Fokker–Planck equation to show that rotational diffusion is described by the effective mean field potential, which includes photoinduced and van der Waals interactions. Our findings underscore the potential of mean field theory for intermolecular couplings in photoaligned surfaces, opening up new pathways of molecular design for a broad range of parameters. Full article

The field of interior home design has witnessed a growing utilization of machine learning. However, the subjective nature of aesthetics poses a significant challenge due to its variability among individuals and cultures. This paper proposes an applied machine learning method to enhance manufactured custom doors in a proper and aesthetic home design environment. Since there are millions of possible custom door models based on door types, wood species, dyeing, paint, and glass types, it is impossible to foresee a home design model fitting every custom door. To generate the classification data, a home design expert has to label thousands of door/home design combinations with the different colors and shades utilized in home designs. These data train a random forest classifier in a supervised learning context. The classifier predicts a home design according to a particular custom door. This method is applied in the following context: A web page displays a choice of doors to a customer. The customer selects the desired door properties, which are sent to a server that returns an aesthetic home design model for this door. This door configuration generates a series of images through the Unity 3D engine module, which are returned to the web client. The customer finally visualizes their door in an aesthetic home design context. The results show the random forest classifier’s good performance, with an accuracy level of 86.8%, in predicting suitable home design, marking the way for future developments requiring subjective evaluations. The results are also explained using a feature importance graphic, a decision tree, a confusion matrix, and text. Full article

Pyroelectric materials have the ability to convert the environmental cold–hot thermal energy such as day–night temperature alternation into electrical energy. The novel pyro-catalysis technology can be designed and realized on the basis of the product coupling between pyroelectric and electrochemical redox effects, which is helpful for the actual dye decomposition. The organic two-dimensional (2D) graphic carbon nitride (g-C₃N₄), as an analogue of graphite, has attracted considerable interest in the field of material science; however, its pyroelectric effect has rarely been reported. In this work, the remarkable pyro-catalytic performance was achieved in the 2D organic g-C₃N₄ nanosheet catalyst materials under the continuous room-temperature cold–hot thermal cycling excitation from 25 °C to 60 °C. The pyro-catalytic RhB dye decoloration efficiency of the 2D organic g-C₃N₄ can reach ~92.6%. Active species such as the superoxide radicals and hydroxyl radicals are observed as the intermediate products in the pyro-catalysis process of the 2D organic g-C₃N₄ nanosheets. The pyro-catalysis of the 2D organic g-C₃N₄ nanosheets provides efficient technology for wastewater treatment applications, utilizing the ambient cold–hot alternation temperature variations in future. Full article

Actually, the quality of water is one of the most important indicators of the human environmental impact, the control of which is crucial to avoiding irreversible damage in the future. Nowadays, in parallel to the growth of the chemical industry, new chemical compounds have been developed, such as dyes and medicines. The increasing use of these products has led to the appearance of recalcitrant pollutants in industrial wastewater, and even in the drinking water circuit of our populations. The current work presents a photoreactor prototype that allows the performance of experiments for the decomposition of coloured pollutants using photocatalysis at the laboratory scale. The design of this device included the study of the photometric technique for light emission and the development of a software that allows monitoring the dye degradation process. Open-source hardware platforms, such as Arduino, were used for the monitoring system, which have the advantages of being low-cost platforms. A software application that manages the communication of the reactor with the computer and graphically displays the data read by the sensor was also developed. The results obtained demonstrated that this device can accelerate the photodegradation reaction in addition to monitoring the changes throughout the process. Full article

Due to population growth and industrial development consumption of non-renewable energy sources, and consequently pollution, has increased. In order to reduce energy utilisation and preserve the environment, developed and developing countries are increasingly trying to find solutions based on renewable energy sources. Cost-effective wastewater treatment methods using solar energy would significantly ensure effective water source utilisation, thereby contributing towards sustainable development goals. In this paper, special emphasis is given to the use of solar energy as the driving force of the process, as well as the use of highly active magnetic TiO₂-based catalysts. Therefore, in this study, we investigated the possibility of photocatalytic degradation of aqueous magenta graphic dye using titanium dioxide as a catalyst and DSD model in order to achieve the best process optimisation. TiO₂ was successfully coated with magnetic nanoparticles by one step process and characterized using different techniques (BET, SEM/EDS, FTIR, XRD). Based on DSD statistical method optimal reaction conditions were pH = 6.5; dye concentration 100 mg/L; TiO₂–Fe₃O₄ 0.6 g/L, at which the highest degree of magenta dye decolourisation was achieved (85%). Application of solar energy coupled with magnetic TiO₂ catalyst which could be recovered and reused makes this approach a promising alternative in green wastewater treatment. Full article

In this paper, we publish the algorithm to create a dual image manifested in the infrared and visible spectrum. To distinguish the information in the two light spectra, twin dyes are introduced for the inkjet plotter and printing realization for garment and canvas items. The graphics, invisible to the naked eye, are designed for the near infrared (NIR) spectrum and are suitable for urban security where surveillance cameras with IR detectors are installed. The duality of dyes is presented in tables, and the analysis is a basis for programming and developing new algorithms for the application of “Infrared Dyeing” on different materials and printing technologies. Through spectroscopy, this innovative solution demonstrates twin colorants by printing in one pass through the plotter such that one image remains visible, while the other one is hidden to the bare eye. The uniform and the school bag cover presented in this paper are kept simple in design because they incorporate information hidden to the naked eye but visible with surveillance cameras and all the other infrared detectors. The article provides mathematical models of duality coloring as a basis for programming the graphic prepress that merges both of the images, the visual one and the infrared one. A topic is the fusion of two images with colors that represent two graphs, with independent contents for the visual and near-infrared spectrum. Full article

In this paper, the fusion of four graphics into one integrated graphic is selectively observed in the visible and infrared spectrum. Each graphic represents its own information derived from the following sources: vector graphics, drawing, photograph and textual information. One graphic will be visible to the naked eye after the print. The other graphics will be observed with an NIR surveillance camera. These other graphics are nested into the selected visible graphics. All the graphics together make up a security print product with the characteristics of an individual solution with multilayered elements. Reprinting is possible only for the person in possession of the solution created according to the algorithm based on the INFRAREDESIGN^® method. When these graphics are printed on paper, it is impossible to produce an identical graphic prepress (C, M, Y, K) to produce forgery with the same dual properties in the visible and NIR spectrum. Full article

Over the last years, the documentation of Heritage has been increasingly enriched with new forms of data representation and contents deriving from technological applications on artifacts and the progress of computer graphics: if, on the one hand, 3D survey has become an effective tool supplementing and supporting traditional study activities, as it can generate accurate and high-resolution digital models (available especially when physical access to materials is not possible, but also for enhancement or to formulate hypothetic reconstruction), on the other, archaeometry investigations can provide all that information (about composition, firing temperature of clay, etc.) that autopsy, comparison, formal, contextual, or bibliographic analysis cannot do on their own. This paper aims to show the potentialities of combined use of these non-destructive and non-contact approaches on the archaeological artifacts preserved at the Regional Museum of Lipari "L. Bernabò Brea" for the analysis, diagnostic, fruition, and forthcoming restoration purposes. Different methodologies, such as laser-based surveying, sfm digital photogrammetry, and Raman spectroscopy have been, respectively, adopted and combined to get reconstruction and characterize several clay masks and two figured calyx-kraters. The latter technique, in particular, has proved to be useful in compositional analysis of dyes and pigments contained in the clay. Full article

In this paper, we present the development of a handheld common-path swept source optical coherence tomography (CP-SSOCT) guided microinjector system and demonstrated its utility by precisely injecting fluorescein dye in the subretinal layer of ex vivo bovine eyes. The system enables precise subretinal injection with micron-level injection depth control. This was achieved by using a high-resolution CP-SSOCT distal sensor and signal processing using a graphics-processing unit (GPU), which made a real-time smart motion control algorithm possible. The microinjector performance was first evaluated using a gelatin phantom in terms of its ability for dynamic depth targeting and injection depth. This is followed by using an ex vivo bovine eye model to perform multiple consecutive subretinal injections of fluorescein dye. The results validated the OCT guided injector’s ability to precisely guide and lock in the needle tip to the target depth during injection. The ex vivo evaluation tests demonstrate that an OCT-guided injector can consistently guide the injecting needle to the desired depth and is able to maintain the position with 9.38 μm average root mean square error during the injections. Full article

The non-destructive classification of plant materials using optical inspection techniques has been gaining much recent attention in the field of agriculture research. Among them, a near-infrared (NIR) imaging method called optical coherence tomography (OCT) has become a well-known agricultural inspection tool since the last decade. Here we investigated the non-destructive identification capability of OCT to classify diversely stained (with various staining agents) Capsicum annuum seed specimens of different cultivars. A swept source (SS-OCT) system with a spectral band of 1310 nm was used to image unstained control C. annuum seeds along with diversely stained Capsicum seeds, belonging to different cultivar varieties, such as C. annuum cv. PR Ppareum, C. annuum cv. PR Yeol, and C. annuum cv. Asia Jeombo. The obtained cross-sectional images were further analyzed for the changes in the intensity of back-scattered light (resulting due to dye pigment material and internal morphological variations) using a depth scan profiling technique to identify the difference among each seed category. The graphically acquired depth scan profiling results revealed that the control specimens exhibit less back-scattered light intensity in depth scan profiles when compared to the stained seed specimens. Furthermore, a significant back-scattered light intensity difference among each different cultivar group can be identified as well. Thus, the potential capability of OCT based depth scan profiling technique for non-destructive classification of diversely stained C. annum seed specimens of different cultivars can be sufficiently confirmed through the proposed scheme. Hence, when compared to conventional seed sorting techniques, OCT can offer multipurpose advantages by performing sorting of seeds in respective to the dye staining and provides internal structural images non-destructively. Full article

Cellulose fiber is a tremendous natural resource that has broad application in various productions including the textile industry. The dyes, which are commonly used for cellulose printing, are “reactive dyes” because of their high wet fastness and brilliant colors. The interaction of various dyes with the cellulose fiber depends upon the physiochemical properties that are governed by specific features of the dye molecule. The binding pattern of the reactive dye with cellulose fiber is called the ligand-receptor concept. In the current study, the three dimensional quantitative structure property relationship (3D-QSPR) technique was applied to understand the red reactive dyes interactions with the cellulose by the Comparative Molecular Field Analysis (CoMFA) method. This method was successfully utilized to predict a reliable model. The predicted model gives satisfactory statistical results and in the light of these, it was further analyzed. Additionally, the graphical outcomes (contour maps) help us to understand the modification pattern and to correlate the structural changes with respect to the absorptivity. Furthermore, the final selected model has potential to assist in understanding the charachteristics of the external test set. The study could be helpful to design new reactive dyes with better affinity and selectivity for the cellulose fiber. Full article