Paint Research Articles

First dating of a rock painting in Ẓufār (Sultanate of Oman): Low energy plasma oxidation radiocarbon sampling

We successfully measured four radiocarbon dates on two specimens of a black geometric rock painting with a fragment in jeopardy of naturally spalling off in the wall of a rock shelter in the Ẓufār region, in the south of the Sultanate of Oman. Extraction of carbon dioxide (CO2) for radiocarbon dating of the binder in the black pigment of the rock painting specimen was conducted in the plasma oxidation laboratory at the Office of Archeological Studies in Santa Fe, NM. The radiocarbon content was measured on the Swiss ETH-Zürich accelerator mass spectrometer MICADAS. The dates obtained agreed with one another within the statistical uncertainty and the average date of the four samples was 1500 ± 35 radiocarbon years BP. The calendric equivalents of the average date results in calendric calibration date ranges that span the mid-fifth through mid-seventh centuries (440–453 CE, 478–496 CE, and 534–646 CE). This research demonstrates that it is possible to date the black paintings of the Jebel al-Qara’ area of Oman; this is the first pictogram that was dated using radiocarbon dating in the region.

Performance study of an active solar water curtain heating system for Chinese solar greenhouse heating in high latitudes regions

Thermal preservation and heat storage performance cannot be fully realized in the traditional design of the Chinese solar greenhouse (CSG) north wall. To increase greenhouse thermal efficiency and maximize solar energy utilization, researchers have divided greenhouse into the independent solar heating system as well as the independent north wall heat preservation system. The wall-mounted solar heating system used water as a medium with the characteristics of chemical stability, liquidity preference and high specific heat capacity for heat transport and storage have been developed. To explore and create a better suitable greenhouse thermal environment, we proposed an active solar water curtain heating system with a non-woven fabric liner between the two-layer polyethylene film coated with black water-based paint. The greenhouse heating load was estimated based on energy balance theories during the nighttime and the water mass for heat transfer was calculated. Field tests were carried out to verify theories and investigate the thermal performance of the system. The average heat collection ratio was about 80.1 % and 63 % of the stored heat was released at night with the 3.6 °C improvement in interior air temperature and 6.6 % reduction in interior air relative humidity. The heating COP of the system was 12.5 on average and the energy saving rate was 92 %. Besides, the greenhouse with the solar heating system can save energy consumption cost about 348 USD yr−1 as the cost of solar heating system can be repaid in 1.4 years. The system combined the energy balance method to design with more efficient thermal performance, energy conservation, utilization of solar energy and affordable payback period thereby creating a suitable thermal environment in the Chinese solar greenhouse, which is recommended for practical application.

A study of aquatic macrophyte for remediation of chromium and cadmium in wastewater effluents in Yenagoa Metropolis, Niger Delta

Although aquatic macrophytes have been used individually for wastewater remediation, there is a dearth of studies comparing their efficiency level to determine the most effective for remediation of specific heavy metals. This study aimed to determine the most effective aquatic macrophyte amongst Eichhornia crassipes, Pistia stratiotes, Nymphaea nouchalli, Lemna minor and Ceratophyllum demersum for the remediation of Cr and Cd from wastewater effluents in Yenagoa Metropolis, Niger Delta. Wastewater samples from emulsion paint industries were collected from six locations (L1-L6) and analyzed for Cr and Cd concentration using Inductively Coupled Plasma Atomic Emission Spectroscopy. The wastewater samples were treated with these aquatic macrophytes and the concentration of Cr and Cd in the samples were assessed every two weeks for six weeks. Results showed that the mean Cr concentration (0.27mg/L) and Cd levels (0.080mg/L) in the wastewater samples were higher than the recommended WHO limits of 0.05 and 0.003mg/L respectively. The treated wastewater showed that Cr and Cd concentrations in the wastewater were reduced to minimum values by P. statiotes (0.003±0.001mg/L) and E. crassipes (0.000±0.000mg/L) respectively. The removal potentials of the macrophytes were in the order of P. stratiotes > E. crassipes > N. nouchalli > L. minor > C. demersum for Cr, and E. crassipes > P. stratiotes > N. nouchalli > C. demersum > L. minor for Cd. It was concluded that the most effective aquatic macrophyte for remediation of Cr was P. stratiotes (with 97% efficiency) and Cd was E. crassipes (87.5% efficiency). Therefore the macrophytes were considered good phytoremediators.

Synthesis of phase change microcapsules based dispersants for waterborne coatings and their effects on paint film properties

The hyperdispersant SSS-MPEGA-MA (SMM) is prepared through aqueous polymerization using sodium p-styrenesulfonate (SSS), polyethylene glycol monomethyl ether acrylate (MPEGA) and maleic anhydride (MA) as monomers for dispersing phase change microcapsules (PCM). It is also concluded that the best dispersion effect is achieved when the starting concentration of SMM dispersant in aqueous solution with a solid content of phase change microcapsules of 20% occupies 2% of PCM content. The phase change microcapsules are added to a waterborne varnish with a solid content of 20%, and after adding a certain mass of SMM dispersant dropwise, phase change performance is still found on the film, which is the best with a dispersant concentration of 2%. At the same time, the hyperdispersant SMM can make the phase change microcapsules evenly distributed on the water-based varnish, and the dispersion effect is good without affecting the properties of the paint film itself.

Properties of Emulsion Paints with Binders Based on Natural Latex Grafting Styrene and Methyl Methacrylate

Infrastructure developments in recent decades have led to increasing demand for high-performance paints for construction and decorative purposes. Emulsion paint is water-based paint that is commonly used for coating the internal and external surfaces of a building. The quality and performance of this emulsion paint are highly dependent on its constituent components, such as binders, pigment, solvents, and additives. Emulsion paints initially used conventional formaldehyde-based binders and were, for some reason, prohibited from being used in paints due to health and environmental issues. The development of bio-based paints with natural rubber latex (NRL) has the potential to be developed as an emulsion paint binder. The results showed that NRL grafting of styrene monomer or MMA showed much better resistance to wet scrub and abrasion than PVAc at a monomer concentration of 20%, for styrene, and 30%, for MMA, with washability values reaching each of 11 and 12 cycles at 4% binder concentration. The NgSt20-4 and NgMMA30-4 binders’ abilities to overcome wet scrub and abrasion increased with increasing paint binder concentrations, reaching 22 and 23 cycles at 10% binder concentration. Overall, the combination of NRL grafted with MMA monomer and 30% PVAc showed better performance and could compete with commercial binders such as PVAc. Adding methyl methacrylate monomer increases the adhesion and cohesion properties of the binder and increases the binder’s resistance to scrubbing and wet abrasion. However, the combination of NRL grafted MMA and 30% PVAc showed the same effectiveness as NRL grafted MMA without PVAc, with more economical production costs.

Enhancing the Mechanical Properties of Waterborne Polyurethane Paint by Graphene Oxide for Wood Products.

Water-based polyurethane paint is widely used for wood furniture by virtue of the eco-friendliness, rich gloss, and flexible tailorability of its mechanical properties. However, its low solution (water or alcohol) resistance and poor hardness and wear resistance limit its application. The emerging graphene oxide has a high specific surface area and abundant functional groups with excellent mechanical properties, endowing it with great potential to modify waterborne polyurethane as a nanofiller. In this study, graphene oxide prepared by Hummers' method is introduced in the chemosynthetic waterborne polyurethane through physical blending. The testing results demonstrate that the appropriate usage of graphene oxide at 0.1 wt% could obviously improve water absorption resistance and alcohol resistance, significantly enhancing the mechanical properties of waterborne polyurethane paint. The corresponding tensile strength, abrasion resistance, and pendulum hardness of the graphene oxide-modified paint film increase by 62.23%, 14.76%, and 12.7%, respectively, compared with the pristine paint film. Meanwhile, the composite paint film containing graphene oxide possesses superiority, including gloss, abrasion resistance, pendulum hardness, and tensile strength in contrast with the commercial paint. The use of graphene oxide to enhance the waterborne polyurethane possesses strong operability and practical value, and could provide useful reference for the modification of waterborne wood paint.

Quality improvement of long oil alkyd (LOA) resin requirements in the formulation of Hi-gloss paints

PurposeThis research aimed at lowering the non-volatile matter (NVM) of long oil alkyd (LOA) resin to meet the resin requirements in producing Hi-gloss paints. The research also aimed to assist Hi-gloss paint manufacturers who require solid resin content below 70%.Design/methodology/approachThe research utilised both the document review and experimental methods. The experimental method, which involved the blending process, was used in lowering the NVM of LOA resin, whereby eight experiments were conducted as reputations to obtain accurate data and results. A factorial design was used in the design of the experiment (DOE), where three factors were required to be evaluated: specific gravity, viscosity and NVM and two levels were required: weight of LOA and white spirit.FindingsThe NVM of LOA resin was successfully lowered, and different shades of paint were produced for reliability testing. The quality parameters of Hi-gloss paints that used the modified LOA were all found within the company's specifications compared to those with unmodified LOA, where some parameters were either above or below the specifications. However, all samples with the NVM of LOA used below 50% were found to be poor in terms of quality during the reliability testing. So, if the company had used the modified LOA resin in the production of Hi-gloss paints, it would have potentially saved 18,925.2 kg and 9,446.4 kg, respectively, of LOA just in producing Hi-gloss black and white paints only. Moreover, the cost of 1 kg of LOA is $2.3, which is equal to Tanzanian Shillings (Tshs) 5,290. The company would have potentially saved Tshs 100.114 million Tshs and Tshs 49.97 million Tshs in producing Hi-gloss black and white paints, respectively, making a total of Tshs 150.08 million per year. This was counted as a loss during that year because they did not use LOA resin with 50% NVM in production.Research limitations/implicationsThis study focused on LOA resin used in producing Hi-gloss paints. The study also did not consider other categories of alkyd resins used in producing paints and varnishes e.g. epoxy resin and short and medium oil alkyd resins.Originality/valueThis is probably the first alkyd resin improvement study conducted using white spirit as Tanzania's main agent or material. The study utilised vegetable oils such as coconut, sunflower and tobacco seeds.

Archaemineralogical study of plasters and paints from the Thracian tomb Maglizh (4th–3rd century BC), Bulgaria

Fragments of plasters and paints from the decoration of the chamber and the grave of the Thracian tomb Muglizh (4th–3rd century BC) were studied. It was established that the plasters are two or three-layered and consist of coarse plaster, pink colored plaster and white putty (stucco). The binder in all three layers is a lime prepared from organogenic limestone. Crushed materials from rocks and minerals were used as fillers in the coarse and pink plasters, and only white-colored minerals such as quartz, calcite, albite were used in the stucco. A mixture of red earth ocher and cinnabar was used as pigment in the red paint and pink plaster. For the black paint, a mixture of crushed charcoal and Egyptian blue was used. The binder in the red and black paints is lime. In pink paint, the binding material is gypsum, and the pigment is cinnabar.

Novel multifunctional acrylic paint from sugarcane bagasse: Photoluminescence, photochromism, hydrophobicity and anticorrosion

Novel graphene oxide-based waterborne acrylic emulsion paints were prepared for multifunctional smart coatings with long-persistent photoluminescence, anticorrosion, hydrophobic and photochromic properties. Environmentally friendly graphene oxide nanosheets were successfully prepared through ferrocene-catalyzed oxidation of sugarcane bagasse agricultural waste under muffled conditions. An acrylic polymer was combined with graphene oxide and lanthanide-doped strontium aluminate nanoparticles to create innovative photoluminescent paint for use in safety marking. The graphene oxide nanosheets were used in the acrylic paint as crosslinker, as well as drying and anticorrosive agent. Different concentrations of lanthanide-doped strontium aluminate nanoparticles were tested. As a result of its unique characteristics, graphene oxide has become an appealing reinforcing agent that can be used in protective paints. The produced acrylic/graphene oxide/lanthanide-activated aluminate coatings were applied onto tinplates. The dispersion of phosphor was improved in the paint matrix by using the phosphor in the nanoscale form (4–8 nm). The morphological properties of the graphene oxide nanosheets were studied. Different research analysis methods were used to examine the morphologies of the applied paints. Photoluminescence spectra and CIE Lab properties were used to analyze the applied paints transparency and colorimetric properties. The photoluminescent transparent paints showed green emission at 518 nm when excited at 365 nm. The prepared paints demonstrated high photostability and durability. Scratching resistance, hydrophobicity, and corrosion resistance were all examined.

On Not Looking Jewish: Visualizing Submerged Memories and Appearances

For more than 25 years, artist Barbara Loftus, born 1946, has developed a substantial body of work, across figurative painting, book works and creative documentary film, rooted in her experience as a second-generation Holocaust survivor. Loftus’s mother, Hildegard Basch [1917–2007], was born into an assimilated middle-class Jewish family but the securities of her comfortable life in Berlin were devastated by the catastrophic events of Nazi Germany. While Hildegard was able to take refuge in England in 1939, the rest of her family—Loftus’s grandparents Sigismund and Herta, and her uncle Heinz—were transported to Auschwitz Birkenau in 1942 and perished in the camp. In August 2021, cultural historian Annebella Pollen visited Loftus’ studio in Brighton, UK, to discuss the enduring themes of her artistic practice and, particularly Loftus’s use of photographs and dress as sources and methods for exploring Jewish identity and post-memory.

Corrosion Inhibition, Inhibitor Environments, and the Role of Machine Learning

Machine learning (ML) is providing a new design paradigm for many areas of technology, including corrosion inhibition. However, ML models require relatively large and diverse training sets to be most effective. This paper provides an overview of developments in corrosion inhibitor research, focussing on how corrosion performance data can be incorporated into machine learning and how large sets of inhibitor performance data that are suitable for training robust ML models can be developed through various corrosion inhibition testing approaches, especially high-throughput performance testing. It examines different types of environments where corrosion by-products and electrolytes operate, with a view to understanding how conventional inhibitor testing methods may be better designed, chosen, and applied to obtain the most useful performance data for inhibitors. The authors explore the role of modern characterisation techniques in defining corrosion chemistry in occluded structures (e.g., lap joints) and examine how corrosion inhibition databases generated by these techniques can be exemplified by recent developments. Finally, the authors briefly discuss how the effects of specific structures, alloy microstructures, leaching structures, and kinetics in paint films may be incorporated into machine learning strategies.

Many Amersfoort hands: Revisiting the making of Albert Eckhout’s Brazilian paintings (1641-1643)

Albert Eckhout’s twenty-one paintings, signed and dated 1641-1643, kept at the National Museum of Denmark, has stirred much speculation as to their making, meaning, and function. Eight impressive larger-than-life depictions of native Brazilian inhabitants and a huge dancing scene of the Tarairiu Indians were presented as gifts to the Danish King Frederik III (1609-1670) in 1654, together with twelve almost square still lifes of exotic fruits and vegetables from Brazil. The present was from the initiator of the paintings, Johan Maurits van Nassau-Siegen (1604-1679), the governor of the Dutch possessions in north-eastern Brazil. Following on the archival, historical and technical reports that have been presented over the years, a re-evaluation of the technical examinations combined with new comparative research points to a more complex genesis of the paintings. The canvases and ground layers suggest that the tall single-figure pieces were made in one batch, while the large dancing scene and the still-lifes were prepared in a small number of separate batches. Infrared imaging visualises different approaches in paint handling within the group of nine figure pieces. The working up of the final paint layer in the faces of the figures has been approached in two different ways, either opaquely or with semi-transparent layers in the shadow areas. Idiosyncratic manners of rendering the eyes complement these findings and reveal details hardly studied so far. The article concludes that the Tupi man, the Black man, and the Mulatto man are painted in a different and more transparent technique. Further, the manner of mixing black paint with white to render a nuanced whiteness of the eyes of the three figures, is not found in any of the other six paintings. These tall figures were painted by another hand than Eckhout, and most probably someone active in Jacob van Campen’s large Randenbroek workshop in Amersfoort. Here, together with the still anonymous painter, Eckhout completed the impressive series of large Brazilian figures and twelve still lifes around 1647-1650. This research exemplifies the seventeenth-century collaborative practice of working on larger commissions, yet all the works continue to demonstrate Eckhout’s legacy and how studies from his Brazilian sojourn were used by a larger community of artists in the Netherlands to satisfy the need for exotic images of the time.

Preparation of Low Volatile Organic Compounds Silver Paste Containing Ternary Conductive Fillers and Optimization of Their Performances.

Conductive silver paste is a key material in the fields of printed circuits and printed electronic devices. However, the preparation of conductive silver paste with low-cost and volatile organic compounds (VOCs) is still a challenge. In this work, conductive silver pastes with excellent comprehensive performances were developed by using water-borne polyurethane (WPU) as the bonding phase and using the ternary mixture of Ag microflakes (Ag MFs), Ag nanowires (Ag NWs), and Ag nanoparticles (Ag NPs) as the conductive phase. WPU endowed conductive silver pastes with the adhesion along with releasing a few VOCs during the curing. Results showed that a small amount of Ag NPs or Ag NWs dramatically enhanced the electrical conductivity of silver paste paint film filled only with Ag MFs. The electrical resistivity for optimal ternary mixture conductive silver paste was 0.2 × 10-3 Ω∙cm, and the conductive phase was composed of 20.0 wt% Ag MFs, 7.5 wt% Ag NWs, and 2.5 wt% Ag NPs. Meanwhile, the adhesive strength and hardness of silver paste paint film were effectively improved by increasing the curing temperature. The optimal overall performance of the conductive silver pastes was achieved at the curing temperature of 160 °C. Therefore, this work can provide a new route for preparing conductive silver pastes with high performances.

Performance analysis and experimental validation of a vee‐corrugated absorber integrated collector storage solar water heater

AbstractThis paper focuses on enhancing the energy collection efficiency of an integrated collector storage solar water heater (ICS SWH) by vee‐corrugating the absorber and optimizing the design for the vee‐included angle through simulation and experimental study. This paper presents an efficient algorithm for analyzing a vee‐corrugated absorber ICS SWH using Engineering Equation Solver Software. For validating this algorithm, two models of ICS SWH systems have been fabricated: one with a flat absorber and the other with a 60° vee‐included angle corrugated absorber with eight corrugations. The basic purpose of the fabrication of the flat absorber ICS SWH system was to approximate the absorptivity of the absorber. A typical value of 0.68 was estimated for the absorptivity of the aluminum absorber coated with nonselective black paint. After the experimental investigation of the 60° vee‐included angle ICS SWH system, it was found that the real‐time readings were in close agreement with the numerical model readings. For comparison with the previous work, a five‐corrugation system with an approximate 90° vee‐included angle with the same projected dimensions was modeled and the efficiencies of both the models for the time from 7 a.m. to 3 p.m. were calculated. The efficiency of the eight‐corrugation model was 42.56%, which was better than the previous work of the five‐corrugation model, with a 38.86% efficiency for the same ambient conditions. Also, it was theoretically deduced that we had an optimized system at 18 corrugations and a vee‐included angle of 28.78°.

Experimental evaluation and thermodynamic Gibbs free energy analysis of a double-slope U-shaped stepped basin solar still using activated carbon with ZnO nanoparticles

Solar distillation methods require expensive energy storage in the basin area to enhance productivity, confirming the cost-effectiveness of natural green dyes as an appealing process. The present study investigated the potential for enhancing productivity of a double-sloped U-shaped stepped basin solar still (DUSS) by covering its sides with matte black paint (BP) mixed with different concentrations of activated carbon nanoparticles (ACNPs). It was prepared from ACNP using Mangifera Indica (M) with Celostia Argentea (C), which consists of carbon powder with doped ZnO nanoparticles (Z) and discussed in the samples. In this case, a U-shaped stepped basin (USB) surface was coated with BP doping with different ratios of 5, 10, 15, 20, and 25 wt% for the ACNP. The USB coated with BP with ZMC was subjected to a thermodynamic study to calculate the entropy change using Gibbs free energy equation. Silver-colored steel balls (SBs) were used to increase convective heat transfer as they could absorb incident solar radiation and transfer it into the BP-ACNP and affect the thermal performance of the DUSS. It was found that ZMC leads to higher heat transfer with a potential of DUSS containing the BPACNP, resulting in an enrichment increase of 20% by weight and an average water temperature of 25%. The performance enhancement of the DUSS with USB-coated BPACNP integrated with SBs was 16.91% compared to the conventional double U-shaped stepped basin solar still (CDUSS). The proposed new design could increase the water temperature of the DUSS and enhance the performance to 14.92 l/m2day with an average daily efficiency of 38.73%. The results of the water quality analysis indicated that the produced distilled water is suitable for drinking. The theoretical and experimental results obtained for the BPACNP-SB integrated with the DUSS indicated an increased thermal conductivity.

Visual Inspection of the Heavy-Duty Paint Systems Used in Steel Bridges for Assessing the Level of Fire Damage

After a fire on a steel bridge, a visual inspection is necessary to rapidly determine the need for an emergency response to ensure the structural safety of the bridge and decide whether to re-open the bridge to traffic. In this study, the visual inspection methods of assessing the coated surface were reviewed, as they are crucial for the rapid estimation of the steel temperature reached during the fire, which, in turn, is required for the safety assessment of steel bridges after a fire. An electric furnace heating test was conducted on the steel specimens coated with four types of heavy-duty paint systems for steel bridges, viz., urethane, siloxane, ceramic, and fluorocarbon. The heating temperatures and durations used in the test were 100, 150, 200, 250, 300, 400, 500, and 600 °C at 30 and 60 min. Based on the heating temperature and duration, the paint-film surface conditions (discoloration, blistering, cracking, and delamination) were visually inspected for a qualitative analysis, and factors such as color difference, gloss retention, and pull-off adhesion were quantitatively analyzed. The visual inspection methods used to estimate the temperature of the paint film were reviewed. In addition, considering the reduction in the tension strength of the steel material and the coating durability performance according to the fire temperature, the determinants of the traffic stop–reopening timeline and the repair and reuse of the painting system based on the visual field inspection after a fire were suggested.

Design a low-cost, medium-scale, flat plate solar air heater: An experimental and simulation study

The most efficient solar air heater is expensive, and attempts to reduce costs lead to reduced efficiency. The current study presents a low-cost, medium-scale, flat plate solar air heater's design, simulation, and experimental thermal analysis. Carbon steel, thermocol, window glass, and aerosol spray paint were utilized for fabrication to decrease manufacturing costs. Initially, a mathematical model was developed, and experimental tests on this system were carried out with different absorber plates and glass covers in various weather conditions. The air mass flow rate of the collector is set at 0.073 kg/s. According to the experimental results, the solar air collector with a finned steel absorption plate, black paint, and double-glazing exhibit optimal performance. Under average solar radiation and ambient temperature of 910 W/m2 and 29.44 °C, respectively, the maximum thermal efficiency is 60.81 %, the average thermal efficiency is 56.01 %, and the average air temperature difference between the inlet and outlet is 40 °C. Whereas, for the solar air collector with plain steel absorber plate and single glazing, the least desirable performance was observed with a maximum collector efficiency of 45.76 %, an average thermal efficiency of 39.22 %, and an average air temperature difference of 20.14 °C between inlet and outlet under average solar radiation and ambient temperature of 810 W/m2 and 29.98 °C, respectively. Compared to the results, the thermal performance of solar air collectors with a finned steel absorption plate, black paint, and double-glazing was improved by 14 % to 20 % under different conditions. In addition, the solar air heater was designed, and a simulation study was performed in COMSOL Multiphysics software to find the temperature distribution of the glass cover and absorber plate. The experimental findings demonstrated that this convenient and cost-effective solar air collector was designed successfully and can be utilized in heating applications.

Nanoindentation of softening modern oil paints

A methodology was developed to address challenges associated with the use of nanoindentation to characterize small volumes of soft-matter thin films, encountered in many research fields including heritage conservation. The methodology is based on the use of a flat-punch indenter, whose radius is so dimensioned to be able to predict the effect of substrate rigidity using an existing solution independently of the film’s Poisson’s ratio and frictional characteristic. The film’s mechanical response is analyzed in a minimally strained condition at the onset of full contact to fulfill the solution’s assumption of linear viscoelasticity. The indentation response prior to full contact is corrected for the substrate effect using a model of structural compliance coupled with the solution. Homogeneity of the film material, further assumed by the solution, can thus be established based on its constant loss tangent response while deforming linear viscoelastically prior to full contact. This methodology was applied to minute volumes of bone black oil paints sampled from modern paintings by Karel Appel and Asger Jorn, across a range of relative humidities. The methodology not only differentiated between viscoelastic behaviors of these paints from the same period, but also facilitated the discovery that they possess softening points below the target humidity range of museums. The latter finding convincingly explains why these paints exhibit conservation problems even in a standard climate-controlled museum environment. The methodology can be applied to polymer coatings and thin biological tissues, whose Poisson’s ratios and frictional characteristics are not exactly known.

Plant growth acceleration using a transparent Eu3+-painted UV-to-red conversion film

The stimulation of photosynthesis is a strategy for achieving sustainable plant production. Red light is useful for plant growth because it is absorbed by chlorophyll pigments, which initiate natural photosynthetic processes. Ultraviolet (UV)-to-red wavelength-converting materials are promising candidates for eco-friendly plant cultures that do not require electric power. In this study, transparent films equipped with a UV-to-red wavelength-converting luminophore, the Eu3+ complex, were prepared on commercially available plastic films for plant growth experiments. The present Eu3+-based films absorb UV light and exhibit strong red luminescence under sunlight. Eu3+-painted films provide significant growth acceleration with size increment and biomass production for vegetal crops and trees in a northern region. The plants cultured with Eu3+-painted films had a 1.2-fold height and 1.4-fold total body biomass than those cultures without the Eu3+ luminophores. The present film can promote the plant production in fields of agriculture and forestry.

Trypillian settlement Bilche Zolote Park I (based on the materials of surveys conducted by Valentyna Kravets in 1952)

Bilche-Zolote Park I belongs to the Zalischyky group of sites, so to determine its place (micro-chronology) inside the group, paintings on ceramics were considered and a comparative analysis with the decor of vessels from other settlements was conducted. Special attention is paid to motifs, elements of ornament, and color solutions. Finds discovered in 1952 were put into scientific use. This material was systematized and supplemented with vessels already known in the literature, excavated at the end of the ХІХ century. The site has three different layers of Trypillia: BI–BII (Bilche-Zolote Park I), B II (Bilche-Zolote Park II), and C I (Bilche-Zolote Park III). Emphasis is placed on the lower layer of Bilche-Zolotye, which belongs to the time of Trypillia BI–BII, and exactly it was found by Valentyna Kravets and Igor Sveshnikov during surveys in 1952 when the Trypillian detachment of the Podillya Archaeological Expedition conducted research in Bilche-Zolote Park. It is noted that the results of the explorations have not been published, and the materials are stored in the holdings of the Archaeological Museum of the I. Krypiakevych Institute of Ukrainian Studies of the National Academy of Sciences of Ukraine. It is stated that the ceramic complex of Bilche-Zolote Park I shows similarities with other sites of the Zalischyky group. It is established that a comparison of motifs and elements of ornament demonstrates that the closest analogies are found among the ceramics of Zalischyky and Buchach. Upon closer inspection, it is noticeable that in terms of colors and motifs, ceramic ware of the Bilche-Golden Park I is more in line with Zalischyky one; in addition, some ornamental solutions (circles in the decoration of goblets, chess ornaments, and «grid») are found on the ceramics of these two settlements and are absent on other sites of this group. It is observed that in the ceramic complex of Bilche-Zolote Park I there are no such archaic styles as β (black and white painting, which forms a negative ornament, built of spirals and volutes) and the earliest variants of the α style, which, although in small number, are present in Zalischyky. It is concluded that the characteristics of the tableware of Bilche-Zolote Park I demonstrate its closer proximity to Zalischyky than to Buchach, which is one of the latest sites of the group. Key words: Bilche-Zolote Park, Trypillia, ceramic ware, painted ornament, Zalischyky group.