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Lorsqu’on libère le paysage du carcan esthétique dans lequel l’ont enfermé (au moins en France) les grands récits de ses origines (Briffaud, 2014), il permet d’embrasser la diversité des regards et des relations qui se nouent entre des individus et leurs environnements. Il devient alors le support privilégié d’une médiation paysagère et il peut s’ouvrir à d’autres disciplines qui en renouvellent l’interprétation. De ce point de vue, la perspective résidentielle développée par Tim Ingold se montre particulièrement riche dans la mesure où elle relève que de telles relations se tissent de façon dynamique dans l’engagement pratique des individus avec leurs environnements. Pour avoir accès aux subtilités de ces perspectives habitantes inséparables des contextes qui les font naître, il semble alors que l’engagement pratique du paysagiste aux côtés des habitants soit capital. C’est cette démarche (dans la continuité de l’approche ethnogéographique mêlant dépaysement et empaysement expérimentée par Dominique Henry [2012], dans les Pyrénées) qui a été choisie pour approcher les paysages du plateau de Millevaches et s’inscrire dans le tissu de relations complexes qui constitue le cœur d’une action paysagère. When we free the landscape from the aesthetic straightjacket in which it has been imprisoned (at least in France) by the great narratives of its origins (Briffaud, 2014), it becomes possible to embrace the diversity of perceptions and relationships formed between people and their environments. The landscape then becomes the best basis upon which to conduct landscape mediation and it can therefore be opened up to other disciplines and reinterpretations. In this regard, the dwelling perspective developed by Tim Ingold is particularly rich because it shows that such relationships are dynamically related to the practical involvement of individuals with their environments. To understand the subtleties of these dwelling perspectives, which are inseparable from the contexts that engender them, it seems that a practical engagement of the landscape architect with the inhabitants is crucial. It is this approach (consistent with the ethno-geographic approach combining disengagement from and engagement with the landscape experimented by Dominique Henry, 2012, in the Pyrenees) that was chosen to approach the landscapes of the Millevaches Plateau and to engage in the web of complex relationships at the heart of landscape action.

In the present research work, ternary composite g-C3N4-WO3/rGO was prepared by using ultrasonic assisted wet impregnation procedure. The prepared ternary composite was characterized by using FT-IR, powder XRD, SEM, and EDX techniques. FTIR studies confirmed the presence of characteristic bonds of the representative components in the composite by showing their characteristic peaks. The XRD pattern of ternary composite g-C3N4-WO3/rGO showed the presence of peaks responsible for monoclinic phase of pure tungsten oxide (WO3) and the characteristic peaks of graphitic C3N4 and GO. SEM studies of g-C3N4-WO3/rGO revealed the presence of randomly dispersed tungsten oxide particles in between agglomerated 2-D layers of carbon nitride and GO sheets. EDX data confirmed the phase purity in the form of elemental composition of the prepared composite and further provided At wt% of each element in the composite. Photocatalytic activity of the synthesized composite was evaluated by performing photocatalytic degradation test of methylene blue (MB). The rate of degradation was measured by using Shimadzu UV-1800 UV-Vis Spectrophotometer by recording the decreasing concentration of dye in terms of their absorbance values. The results exhibited that g-C3N4-WO3/rGO showed better degradation efficiency in 180 min. KEY WORDS: Impregnation, Composite, Photocatalyst, Degradation, Methylene blue Bull. Chem. Soc. Ethiop. 2023, 37(5), 1123-1131. DOI: https://dx.doi.org/10.4314/bcse.v37i5.5 &nbsp

The porosity of die-cast aluminum alloys is a determining factor for the quality of the product. In this paper, we studied the porosity of a selected part of a die-cast AlSi9Cu3(Fe) compressor part by computer tomography and metallography. In the case of this part, the achievable resolution by CT, a non-destructive testing method, was 30 μm—this method could not detect smaller cavities. Based on metallographic analysis, the percentage of defects larger than 30 μm ranges from 10 to 30% of the total number of defects, which represents 75–95% of the defective area (area ratio). Impregnation with methacrylate resin (used to seal cavities to prevent leakage) can be detected with UV-illuminated optical microscopic examination on metallographically prepared specimens. As confirmed by scanning electron microscopy, partial filling and partial impregnation can occur in a system of shrinkage cavities.

Актуальность работы связана с тем, что в настоящее время технологические процессы разведки, добычи, транспортировки георесурсов в нефтедобывающей, горнорудной, угольной, химической и других отраслях промышленности подвержены высокому уровню механизации и автоматизации с участием электрических машин. Надежность и безотказность работы этих машин зависят от состояния витковой изоляции, роль которой играет изоляция обмоток электродвигателей. Показатели надежности этого элемента обмоток закладываются в процессе их производства. При этом существенный вклад в упомянутые показатели вносит технологическая операция пропитки. От того, насколько качественно проведена данная операция, зависит вероятность скрытия дефектов в изоляции обмоток, тепловые свойства электродвигателей, влагостойкость и монолитность обмоток. Поэтому совершенствование процесса пропитки и повышение её эффективности являются весьма злободневными. Цель: создать математическую модель технологической операции пропитки с применением электростатической зарядки струи пропиточного состава и показать, что добиться снижения уровня индуцированного напряжения, используемого для электростатической зарядки струи пропиточного состава, можно путем усиления электрического поля в области сопла, из которого осуществляется полив лобовых частей обмотки пропиточным составом, за счет придания соплу определенной формы. Методы. При создании математической модели применялись классические методы решения дифференциальных уравнений, описывающих электромагнитные поля, и экспериментальные исследования, позволившие установить адекватность созданной модели. Результаты. Приведены результаты моделирования и исследований новой технологии пропитки обмоток электрических машин электростатически заряженной струей пропиточного состава. Создана математическая модель, связывающая коэффициент усиления поля на вершине эллипсовидного сопла с его геометрическими параметрами. Проведена экспериментальная проверка полученной модели, и показана адекватность модели экспериментальным результатам. Представлены данные практического применения полученной модели на заводских установках, показывающие реальную возможность снижения уровня напряжения на сопле и эффективность предлагаемой пропитки обмоток. Показаны преимущества предлагаемой технологии в сравнении с типовыми технологиями пропитки на основе данных, полученных в реальном производстве. Предлагаемая технология позволит существенно снизить вероятность заводского брака из-за витковых замыканий в обмотке, повысить показатели безотказности выпускаемых электродвигателей в процессе приработки и эксплуатации. Relevance of the work is related to the fact that currently the technological processes of exploration, extraction, transportation of georesources in the oil, mining, coal, chemical and other industries are subject to a high level of mechanization and automation involving electric machines. The reliability and trouble-free operation of these machines depend on the state of the winding insulation, the role of which is played by the insulation of the windings of electric motors. Reliability indicators of this element of the windings are laid in the process of their production. At the same time, a significant contribution to the mentioned indicators is made by the technological operation of impregnation. The probability of hiding defects in the insulation of the windings, thermal properties of electric motors, moisture resistance and solidity of the windings depend on how well this operation is carried out. Therefore, the improvement of impregnation and increase of its efficiency are very topical. The purpose of the work is to create a mathematical model of the technological operation of impregnation with the use of electrostatic charging of the impregnating composition jet; to show that it is possible to reduce the level of induced voltage used for electrostatic charging of the impregnating composition jet by strengthening the electric field in the nozzle area, from which the frontal parts of the winding are watered with impregnating composition, by giving the nozzle a certain shape. Methods. When creating a mathematical model, classical methods of solving differential equations describing electromagnetic fields were used, and experimental studies made it possible to establish the adequacy of the created model. Results. The results of modeling and research of a new technology of impregnation of windings of electric machines with an electrostatically charged jet of impregnating composition are presented. A mathematical model was developed linking the field gain at the top of an ellipsoid nozzle with its geometric parameters. The experimental verification of the obtained model was carried out and the adequacy of the model to the experimental results was shown. The data of practical application of the obtained model on real factory installations are presented, showing the real possibility of reducing the voltage level at the nozzle and the effectiveness of the proposed impregnation of the windings. The advantages of the proposed technology are shown in comparison with typical impregnation technologies based on the data obtained in real production. The proposed technology will significantly reduce the likelihood of factory defects due to winding circuits in the windings, will increase the reliability of manufactured electric motors in the process.

The study aimed to test the durability of coatings under natural conditions. The present study focused on the changes in wettability and additional properties of the coatings under natural conditions. The specimens were subjected to outdoor exposure and additionally immersed in the pond. Impregnating porous anodized aluminum is a popular production method for hydrophobic and superhydrophobic surfaces. However, prolonged exposure of such coatings to natural conditions causes leaching of the impregnate and, thus, the loss of hydrophobic properties. After the loss of hydrophobic properties, all kinds of impurities and fouling adhere better to the porous structure. Additionally, deterioration of anti-icing and anti-corrosion properties was observed. Finally, the self-cleaning, anti-fouling, anti-icing and anti-corrosion properties were comparable or even worse to those of the hydrophilic coating. In the case of superhydrophobic specimens, during outdoor exposure there was no loss of superhydrophobicity, self-cleaning and anti-corrosion properties. Still, despite this, the icing delay time dropped. During outdoor exposure, the structure, which initially had anti-icing properties, may degrade. Nevertheless, the hierarchical structure responsible for the superhydrophobic effect can still be preserved. The superhydrophobic coating initially had the best anti-fouling properties. However, the coating was also gradually losing its superhydrophobic properties during water immersion.

Актуальність теми: Проблема твердих побутових відходів є актуальною, оскільки її рішення пов'язане з необхідністю охорони навколишнього середовища та ресурсозбереження. Нині дедалі ширше застосування знаходять комбіновані пакувальні матеріали типу Tetra Pak. Зважаючи на те, що відходи упаковок Tetra Pak практично не розкладаються в природних умовах до 900 років, єдиний шлях їхньої утилізації – це вторинна переробка. Мета і задачі дослідження. Мета магістерської дисертації полягає в підвищенні ресурсозбереження у технології перероблення ламінованої макулатури за рахунок удосконалення технології розволокнення макулатури з відходів паковання для ефективного відокремлення целюлозного волокна від поліетиленової плівки і фольги. Для досягнення вказаної мети було поставлено наступні задачі: 1. проведення аналізу сучасного стану технологій переробки паковання типу Tetra Pak ; 2. дослідження впливу концентрації гідроксиду натрію та температури на процес просочення відходів паковання Tetra Pak; 3. дослідження паперотворних властивостей лабораторних зразків паперу виготовлених з відходів паковання типу Tetra Pak ; 4. порівняння паперотворних властивостей різних відходів паковань типу Tetra Pak; 5. розроблення удосконаленої технологічної схеми вузла розпускання відходів асептичного паковання. Обєкт дослідження – відходи паковання типу Tetra Pak. Предмет дослідження – технологічні процеси перероблення відходів споживання паковання Tetra Pak з-під рідких харчових продуктів; паперотворні властивості паперу отриманого з макулатури. Наукова новизна одержаних результатів: встановлено залежності відносного приросту маси зразків макулатури від концентрації гідроксиду натрію, тривалості просочення та температури гідроксиду натрію; отримано залежності розмелювальної здатності та паперотворних властивостей відходів паковання PurePak, Tetra Prisma Aseptic та Tetra Gemina Aseptic; удосконалено технологічну схему вузла розпуску відходів асептичного паковання. Практичне значення одержаних результатів. Підвищення ресурсозбереження у технології перероблення ламінованої макулатури дозволить отримати технологію більш ефективного використання макулатурної сировини у процесах виготовлення нової картонно-паперової продукції, водночас зберігаючи на достатньо високому рівні фізико-механічні показники якості. Апробація результатів дисертації. Основні положення дисертаційної роботи доповідалися та обговорювалися на ХХІV Міжнародної науково-практичної конференції студентів, аспірантів і молодих вчених «Ресурсозберігаючі технології та обладнання» (3 травня 2023 р., м. Київ, Україна). – С. 110-112; ХХІV Міжнародної науково-практичної конференції студентів, аспірантів і молодих вчених «Ресурсозберігаючі технології та обладнання» (3 травня 2023 р., м. Київ, Україна). – С. 147-150. Публікації. Мовчанюк О.М, Пономаренко Є.В. Вплив концентрації лугу на швидкість просочення відходів паковання Тетра Пак // Вчені записки Таврійського національного університету імені В.І. Вернадського. Серія «Технічні науки». – 2023. – Т. 34 (73). – № 2 та 2 тези доповідей на міжнародні конференції.

This study analyzed the mechanical and electrical characteristics of repair self-sensing composites. In order to ensure homogeneous dispersion of carbon nanotubes (CNTs) in the repair mortar, porous powder was impregnated with the liquid MWCNT, dried, and then pulverized. This CNT powder was named S-CNT, and a repair self-sensing cement composite was fabricated using it with different dosages, by weight, of 3, 6, and 9%. Mechanical and electrical performances of the developed materials were investigated through flexural, compressive, and bonding strengths, dry shrinkage, porosity, and fractional change in resistance (FCR) tests. There was little difference in terms of strength, between the three different composites made with the different dosages of S-CNT. The strength of the composite with 9% of S-CNT was even higher than that of the plain specimen. As a result of measuring drying shrinkage, conducted to evaluate the effect of improving dispersion, the length change rate decreased as the amount of S-CNT increased. As a result of the porosity results of the specimens incorporating the same mass of CNT as S-CNT, it was confirmed that the dispersibility was clearly improved. In addition, as an electrical characteristic, when the S-CNT mixed specimen was repeatedly loaded with a bending load, FCR appeared, confirming the self-sensing performance.

International audience; The incorporation of vertically aligned carbon nanotubes (VACNTs) between composites plies has been said to enhance the through-thickness strength, and it can also decrease the risk of interply delamination and reduce crack initiation. Thanks to these high mechanical performances, nano-engineered hybrid composites are seen as promising for highly demanding structural reinforcement applications. This paper is part of a study that focuses specifically on the methodology for transferring VACNTs onto a prepreg surface while maintaining their initial vertically aligned morphology. The chosen method involved bonding the VACNTs’ forest through capillary impregnation of the forest by the prepreg’s resin. Key parameters for an effective transfer and to achieve a partial capillary rise of the resin into the VACNTs will be discussed here.

The impregnation of poorly water-soluble drug onto the surface of a suitable pharmaceutical excipient, used as a hydrophilic carrier, can lead to the preparation of systems with improved dissolution properties due to the separation of drug crystal particles on the carrier surface. For this purpose, a method based on impregnation of hydrophilic matrix by the hydrophobic poorly water-soluble drug Meloxicam (MX) solution in volatile organic solvent was used. After the evaporation of the solvent, the method resulted in coverage of the carrier surface by drug crystals. The influence of the amount and concentration of the impregnating solution on the formed MX crystal size and the dissolution rate was evaluated. Firstly, the impregnation forming crystals on the planar surface was studied and the MX maximum dissolution flux from that surface was determined. The optimum preparation method was further used to produce a volume of impregnated granules. The dissolution performance of the granules was evaluated, and the dissolution kinetics was described by mathematical models. The polymorphic modification of impregnated API and influence of impregnated drug amount on the hydrophilic carrier surface coverage were considered. From the results of this work, it is clear that the impregnated drug amount and the number of impregnations cycles can be optimized to achieve maximum drug release rate.

The rheology of the polymer matrix plays a crucial role in determining the quality of thermoplastic laminates. To highlight this aspect, we prepared laminates based on polyamide 11 (PA11), a bio-based matrix with tricky rheology, and basalt fiber fabrics. The PA11 viscosity rapidly increases over time due to degradation phenomena. Samples were prepared by two procedures differing in terms of duration and intensity of the hot compaction step. Morphological analyses revealed that the fast procedure ensures a better impregnation of the fabrics, with a substantial reduction of the volume of voids (1%, against 9% of the slow procedure). This reflects in considerable increases of the flexural modulus (ca. + 20%) and strength (ca. + 60%) and a significant reduction the extent of impact damage. This study provides useful guidelines for a correct selection of the processing parameters based on the knowledge of the rheological behavior of the polymer matrix.

Copper modified titanium dioxide photocatalysts have been widely reported for their excellent performance in the wastewater treatment. However, there is lack of information on the effect of different synthesis methods towards the properties and catalytic activity of the photocatalyst. In this research, a series of copper-doped titanium dioxide (Cu-TiO2) photocatalysts were synthesized via three different methods of sonochemical, impregnation and physical mixing. Cu-TiO2 with varied molar ratios of Cu dopant to TiO2 TR595 (100:0, 99:1, 98:2, 97:3 and 96:4) were prepared. Comparison of physical-chemical properties and photocatalytic activity among the synthesized samples were made. X-ray diffraction analysis depicted the formation of TiO2 rutile phase in all samples. Besides, diffuse reflectance UV-visible analysis proved that the synthesized samples were active under visible light region. According to the Tauc plot and photoluminescence spectra, the band gap energies and recombination rate of electron-hole pairs of Cu-TiO2 samples decreased upon loading of Cu. Moreover, EDX analysis confirmed the existence of Ti and Cu in all the samples. The photocatalytic efficiencies of the synthesized samples were discovered through photodegradation of Rhodamine B organic dye under 6 hours of visible light irradiation. Amongst, Cu-TiO2 photocatalysts synthesized via sonochemical method with molar ratio of 98:2 produced the highest photocatalytic activity of 64.8% which attributed to the lowest recombination rate of photogenerated charge carriers and availability of large number of reactive oxidative species.

Decline in catalyst performance due to coke deposition is the main problem in diesel steam (SR) and autothermal reforming (ATR) reactions. Good redox potential and strong interaction of CeO2 with nickel increase activity and coke resistivity of Ni/Al2O3 catalysts. In this study, mesoporous Al2O3, CeO2/Al2O3, and CeO2/ZrO2/Al2O3 supported nickel catalysts were successfully synthesized. The highest hydrogen yield, 97.7%, and almost no coke deposition were observed with CeO2/ZrO2/Al2O3 catalyst (Ni@8CeO(2)-2ZrO(2)-Al2O3-EISA) in SR reaction. The second highest hydrogen yield, 91.4%, was obtained with CeO2/Al2O3 catalyst (Ni@10CeO(2)/Al2O3-EISA) with 0.3 wt% coke deposition. Presence of ZrO2 prevented the transformation of cubic CeO2 into CeAlO3, which enhanced water gas shift reaction (WGSR) activity. Ni@10CeO(2)/Al2O3-EISA did not show any decline in activity in a long-term performance test. Higher CeO2 incorporation (20 wt%) caused lower steam reforming activity. Change of synthesis route from one-pot to impregnation for the CeO2 incorporation decreased the number of acid sites, limiting cracking reactions and causing a significant drop in hydrogen production. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

The impregnation of elements made of wood is one of the most important stages of their maintenance and the modification of their parameters. Incorrectly prepared material is sensitive to moisture, fungi, algae or weather conditions. In the case of large wooden elements or ready-made installations, impregnation is often performed not indoors, but outdoors. Despite the obvious advantages, this solution also has a number of disadvantages. One of them is the long duration of the impregnation process, as well as the variability in the process parameters along with changing weather conditions. In addition, the final material properties may differ not only from batch to batch, but also within the batch. In order to eliminate these problems, the equipment for wood impregnation was modernized. As part of the work, models of installation elements were made, a computer simulation was performed, and the necessary design calculations were carried out. The work will be crowned with the practical implementation of the proposed solutions in test equipment and the verification of design assumptions. The effect of the modernization of the system was a significant shortening of the impregnation process, as well the ability to obtain a final product of higher quality.

In this study, the hybrid Entropy-TOPSIS method is applied to the problem of selecting an optimal impregnation material with maximum performance requirements. Swelling, shrinkage, bending strength, modulus of elasticity, compressive strength and shock strength values were used to rank the impregnation materials. Barite, boric acid, borax and their mixture were used to impregnation material. The impregnation materials used in the study generally increased the physical and mechanical properties of the spruce specimens, except swelling. The impregnation materials reduced the swelling of the specimens. According to the entropy method, the most important factor affecting the success of the impregnation process was the modulus of elasticity. According to the TOPSIS method, the most successful impregnation material was a mixture of barite and boric acid. Moreover, the proposed method was compared with other Multi-Criteria Decision-Making (MCDM) approaches and it can be used to ranking of impregnation materials with reliable accuracy.

In this work, La1−xSrxNi0.4Fe0.6O3-δ (0 ≤ x ≤ 0.2) oxides were synthesized and employed as the identical electrode of direct methane symmetrical solid oxide fuel cell (SSOFC). In addition, the phase structure, redox stability, electrical conductivity, chemical compatibility, and thermal expansion of La1−xSrxNi0.4Fe0.6O3-δ oxides were evaluated. The La2NiO4 phase occurs when the amount of doped Sr rises to 0.2. The composition of La0.9Sr0.1Ni0.4Fe0.6O3-δ (LSNF9146) boasts the highest conductivity of 463 S cm−1 with lowest activation energy of 0.066 eV as well as a relatively large thermal expansion coefficient. After treatment in methane for 10 h, the LSNF9146 oxide exhibits 33% lower carbon deposition than the LaNi0.4Fe0.6O3-δ (LNF46) oxide. Moreover, the impregnated LSNF9146 electrode demonstrates lower polarization resistance in both air and methane atmospheres. SSOFCs with impregnated LSNF9146 and LNF46 identical composite electrodes have the maximum power densities of 233 and 170 mW cm−2 at 850 °C in methane, respectively. These results prove that LSNF9146 is a promising symmetrical electrode with high catalytic activity, good redox stability, and coking resistance to direct methane SSOFCs.

In Drosophila melanogaster, pheromonal communication is mainly mediated through sex-specific cuticular hydrocarbons (and derived compounds) and the male lipidic pheromone 11 - cis - Vaccényl Acétate (cVA). When deposited together on the feeding substrate they attract conspecifics males and females, promoting mating and collective behaviors. Initially described as stereotyped, recent findings showed that adult response to pheromones could be plastic and depend on the juvenile experience of an individual (i.e. imprinting). In this context, we studied cVA imprinting through its aggregative effect in individuals whose imprinting has been manipulated.The first goal, behavioral, was to study long-range attraction of cVA (or not)-imprinted males and females presented with a dual food choice in a flight tunnel. Foods were either naturally labelled by conspecifics (depositing their pheromonal and microbial compounds) or manually enriched with cVA. This first experiment was completed by the analysis of labeled food headspaces to decipher sources and natures of volatiles odorant compounds attracting Drosophila. This experiment highlighted the necessity of an early larval contact with cVA to modulate adult attraction to the pheromone. However, manual larval exposure to cVA alone was not sufficient to fully restore adult attraction,which may indicate that other compounds are needed in the pheromone imprinting. Food choice finally appeared to be a sex-specific behavior dependent on the nature of the food labelling and the dual food choice presented.The second goal was to study the electrophysiological antennal response of cVA (or not)-imprinted males and females when presented with a short-range puff of the pheromone. Recording showed modulation of the peripheric response according to pre-imaginal exposure to cVA but not the sex. It seems that sex-specific long-range attraction in the flight tunnel is rather explained by the central dimorphism of cVA–neural olfactory system than by a different peripheral detection of the pheromone. Finally, the similarity of peripheric response in unimprinted and manually imprinted individuals to cVA alone support the hypothesis that larval imprinting to cVA needs additional parental compounds to be fully effective in adult., Chez Drosophila melanogaster, la communication phéromonale se fait majoritairement au moyen des hydrocarbures cuticulaires sexuellement spécifiques (et de produits dérivés) et du 11 - cis - vaccényl acétate (cVA), phéromone lipidique mâle. Leur dépôt conjoint sur la nourriture, véritable signature chimique de l’espèce, attire mâles et femelles conspécifiques et favorise accouplements et comportements collectifs. Initialement décrite comme stéréotypée, il a récemment été montré que la réponse adulte aux phéromones pouvait cependant être plastique et dépendre notamment de l’expérience juvénile d’un individu (i.e. imprégnation). Dans ce contexte, le phénomène d’empreinte au cVA a fait l’objet d’une analyse à travers l’étude du rôle agrégatif de la phéromone chez des individus dont l’imprégnation a été manipulée.La première échelle, comportementale, avait pour but d’étudier l’attraction à distance de mâles et femelles imprégnées ou non au cVA vers un choix de nourritures marquées au moyen d’un tunnel de vol. Le marquage était soit réalisé naturellement par les dépôts phéromonaux et microbiotiques de conspécifiques, soit manuellement par dépôt de cVA synthétique. Cette première expérience a fait l’objet d’une analyse complémentaire des espaces de tête des nourritures utilisées visant à étudier la nature et l’origine des odorants émis. Les résultats ont mis en évidence la nécessité d’un contact larvaire avec le cVA dans la modulation de l’attraction adulte à la phéromone, cependant l’exposition synthétique au cVA seul ne suffit pas à rétablir pleinement l’attraction naturelle, supposant que d’autres composés sont impliqués dans l’imprégnation. L’attractivité des nourritures apparait de plus dépendante du sexe de la Drosophile testée, de la nature du marquage présent sur la nourriture et du choix de nourritures proposées.La deuxième échelle, électrophysiologique, avait pour but d’étudier la réponse antennaire de mâles et femelles imprégnés ou non au cVA lors de la diffusion à courte distance de la phéromone. Les enregistrements ont mis en évidence l’existence de différences de réponses périphériques selon l’exposition pré-imaginale à la phéromone, mais pas selon le sexe. Il semble donc que les différences de comportements observables entre mâles et femelles en tunnel de vol s’expliquent par le dimorphisme central de circuiterie du cVA plutôt que par une détection périphérique différente de la phéromone. Finalement, l’absence de différence de réponses entre les individus non – imprégnés et synthétiquement imprégnés soutient davantage la nécessité de contact avec d’autres composés en plus du cVA pendant la période larvaire afin de permettre l’imprégnation totale à la phéromone.

In the field of hairpin stator technology, increasing demands are currently being made on the semi-finished product of insulated flat copper wire. In particular, the focus is on the electrical requirements against the background of increasing voltage levels to 800 V and more. The test procedures described in the standards IEC 60317 & 60851 for verifying the properties of insulated flat copper wires only partially map the requirements from the point of automotive industry. An example for insufficiently considered properties lays in the correlation between wire and insulation resin. In addition to electrical and thermal benefits, impregnation helps to mechanically stabilize the winding and protect it from ambient factors. Adhesion between the winding and the impregnating resin is a key parameter here, but is not considered in material pre-selection today. The adhesion of the impregnation resin to the insulated wire is essential to ensure the lifetime of electric motors. This paper describes a method for determining the adhesion of the impregnating resin to the insulation of the wire. It could be shown that there is a correlation between the material of the wire insulation and the impregnating resin in terms of adhesion. Further on the described method can be used for an application-oriented specification of insulated copper flat wires to ensure a consistent composition of the insulation material.

This study aimed to improve some surface properties such as color, gloss, and surface roughness changes of Oriental beech (Fagus orientalis L.) wood impregnated with some water repellent chemicals such as glycerol (GR) and glyoxal (GX) after weathering. Oriental beech wood specimens were impregnated with a 4 % aqueous solution of GR, GX, and a mixture of GR and GX (1:1; weight : weight) (GR+GX) and then exposed to weathering in Muğla Province in Turkey. Results showed that [delta]L* values of all wood specimens were decreased after weathering. Moreover, the decreases in the control specimen were higher than in the impregnated wood specimens. Oriental beech wood specimens showed a greenish and yellowish tendency, giving -[delta]a* and +[delta]b* values, respectively. Total color changes of GR impregnated Oriental beech was the lowest after weathering. The gloss of all Oriental beech test specimens decreased after weathering. The control specimen gave the lowest value in all three surface roughness parameters (Ra, Rz, and Rq) after weathering. Among the impregnated specimens, the groups impregnated with GR had, in general, the highest value in all three roughness degrees and showed the most negative results in surface roughness., Cilj ovog istraživanja bilo je poboljšanje nekih svojstava, npr. promjene boje, sjaja i hrapavosti površine drva kavkaske bukve (Fagus orientalis L.) impregnirane vodoodbojnim kemikalija kao što su glicerol (GR) i glioksal (GX) nakon izlaganja vremenskim utjecajima. Uzorci drva kavkaske bukve impregnirani su 4 %-tnom vodenom otopinom glicerola, glioksala i mješavine glicerola i glioksala (1 : 1; v : v) (GR + GX) te su zatim izloženi vremenskim uvjetima u provinciji Muğla u Turskoj. Rezultati su pokazali da su vrijednosti [delta]L* svojstava svih uzoraka drva nakon izlaganja vremenskim uvjetima smanjene. Nadalje, smanjenje tih vrijednosti na kontrolnim je uzorcima bilo veće nego na impregniranima. Uzorci drva kavkaske bukve pokazali su tendenciju povećanja zelenoga (-[delta]a*) i žutog tona (+[delta]b). Nakon izlaganja vremenskim utjecajima ukupne promjene boje ispitivanog drva kavkaske bukve impregniranoga glicerolom bile su najmanje. Sjaj svih uzoraka ispitivanog drva smanjio se nakon izlaganja vremenskim utjecajima. Pri izlaganju vremenskim uvjetima i nakon toga kontrolni je uzorak imao najmanju hrapavost površine za sva tri parametra hrapavosti (Ra, Rz, i Rq). Od impregniranih uzoraka najveće vrijednosti svih triju parametara hrapavosti imali su uzorci impregnirani glicerolom, koji su pokazali i najlošije rezultate hrapavosti površine.

Training of accelerator magnets is a costly and time consuming process. The number of training quenches must therefore be reduced to a minimum. We investigate training of impregnated Nb3Sn Rutherford cable in a small-scale experiment named BOX (BOnding Experiment). The test involves a Rutherford cable impregnated in a meandering channel simulating the environment of a canted-cosine-theta (CCT) coil. The sample is powered using a transformer and the Lorentz force is generated by an externally applied magnetic field. The low material and helium consumption enable the test of a larger number of samples. In this article, we present training of samples impregnated with alumina-filled epoxy resins, a modified resin with paraffin-like mechanical properties, and a new tough resin in development at ETH Zürich. These new data are compared with previous results published earlier. Compared to samples with unfilled epoxy resin, those with alumina-filled epoxy show favorable training properties with higher initial quench currents and fewer training quenches before reaching 80% of the critical current., IEEE Transactions on Applied Superconductivity, 33 (5), ISSN:1051-8223, ISSN:1558-2515

One of the most important industries is the extraction and processing of natural stone, which is characterized by a large number of types of facing stone with a wide color palette, which are known not only in Ukraine, but also in the world. From 255 deposits of facing stone as at 01.01.2021, 137 deposits are being developed, which are represented by such minerals as: granite, granodiorite, enderbite, granosienite, sienite, quartz sienite, monzonite, gabbro, anorthosite, labradorite, sandstone, basalt, marble, marbled limestone, limestone, andesite, tuff. A statistical analysis of the decorative stone market of Ukraine for 2019–2021 was carried out, which showed that in recent years there has been a decline in the volume of decorative stone exports in Ukraine. Every year, Ukraine is increasingly maintaining trade and economic relations in the field of natural stone mining and processing with many countries of the world. In order to reduce the negative effects of global processes, enterprise planning should be carried out through institutionalization, which will allow domestic natural stone companies to become more competitive both in the country and in the global market and have a stronger structure for pandemics and political situations, etc. This is achieved by introducing digital fairs rather than classical commercial methods. Global processes have also shown that, as in other industries, the natural stone industry needs to look for new markets and create alternatives. Sharing risk between alternative markets will strengthen the industry economically. Therefore, by reviewing these issues, increasing the number of companies that have completed their institutionalization and branding in the light of science and technology, as well as entering new markets through new remote marketing methods, will make the industry less affected by any crisis., Однією із важливих галузей промисловості є видобування та переробка природного каменю, яка характеризується великою кількістю видів каменю облицювального з широкою кольоровою палітрою, які відомі не тільки в Україні, але і у світі. З 255 родовищ каменю облицювального станом на 01.01.2021 р. розробляється 137 родовищ, які представлені такими корисними копалинами, як: граніт, гранодіорит, ендербіт, граносієніт, сієніт, кварцовий сієніт, монцоніт, габро, анортозит, лабрадорит, пісковик, базальт, мармур, мармуризований вапняк, вапняк, андезит, туф. Було проведено статистичний аналіз ринку декоративного каміння України за 2019–2021 рр., який показав, що протягом останніх років в Україні спостерігається спад обсягів експорту декоративного каменю. Україна з кожним роком все активніше підтримує торгово-економічні відносини у сфері видобування та обробки природного каменю з багатьма країнами світу. Для зменшення негативних наслідків глобальних процесів планування діяльності підприємств має здійснюватися шляхом інституціоналізації, що дозволить вітчизняним компаніям з виробництва природного каменю стати більш конкурентоспроможними як у країні, так і на світовому ринку та бути стійкими до пандемій та політичних ситуацій тощо. Це досягається впровадженням не класичних комерційних методів, а саме утворенням цифрових ярмарок. Також глобальні процеси показали, що, як і в інших галузях, у промисловості природного каменю необхідно шукати нові ринки та створювати альтернативи. Розподіл ризику між альтернативними ринками зміцнить галузь економічно. Тому, завдяки огляду цих питань, збільшення кількості компаній, які завершили свою інституціоналізацію та брендинг у світлі науки і технологій, а також вихід на нові ринки за допомогою нових методів дистанційного маркетингу зробить галузь менш постраждалою від будь-якої кризи.

The aim of this study was to determine some physical and mechanical properties of spruce (Picea orientalis) wood, which was impregnated with aqueous solutions of valonia (valex) (the extract of Quercus ithaburensis), pine bark powder (pinex) (Pinus brutia Ten.) and gallnut powder (galex) (Quercus infectoria Oliver) as a pre-treatment and then heat treated. Test specimens were prepared from sapwood of spruce wood and impregnated with 10% tannin solutions before heat treatment base on ASTM D 1413-76. After pre-impregnation processs, specimens subjected to heat treatment at 150 °C, 175 °C and 200 °C for 2 h. The effect of impregnation process and heat treatment temperature on the air-dried density, compressive strength paralell to the grain (CS), bending strength (MOR) and modulus of elasticity in bending (MOE) were analyzed. As results, impregnation solutions showed positive effects on mechanical strength in unheat-treated samples and determined that mecnaical strength loses due to heat treatment slightly limited at low temperatures. However, strength loses increased with increasing temperature. The highest strength loses were also determined in impregnated samples with galex extract and heat-treated samples at 200 °C., Bu çalışmanın amacı, ön işlem olarak meşe palamudu (valex) (Quercus ithaburensis), kızılçam kabuğu (pinex) (Pinus brutia Ten.) ve meşe mazısı (galex) (Quercus infectoria Oliver) ekstraktlarının sulu çözeltileri ile emprenye edildikten sonra ısıl işleme tabi tutulan ladin (Picea orientalis) odunun bazı fiziksel ve mekanik özelliklerinin belirlenmesidir. Test örnekleri, ladin ağacının diri odun kısmından hazırlanmış ve ısıl işlemden önce ASTM D 1413-76'ya göre %10 tanen çözeltileri ile emprenye edilmiştir. Ön emprenye işlemlerinden sonra, test örnekleri 150 °C, 175 °C ve 200 °C'de 2 saat süreyle ısıl işleme tabi tutulmuştur. Emprenye ve ısıl işlemin hava kurusu yoğunluk, liflere paralel basınç direnci (CS), eğilme direnci (MOR) ve eğilmede elastikiyet modülüne (MOE) etkileri analiz edilmiştir. Sonuç olarak, emprenye çözeltilerinin ısıl işlem uygulanmamış örneklerinde mekanik özellikleri olumlu etkilediği ve düşük sıcaklıklarda ısıl işlemden kaynaklanan direnç kayıplarını bir miktar sınırladığı tespit edilmiştir. Ancak artan sıcaklıkla beraber direnç kayıpları da artmıştır. En yüksek direnç kayıpları, galex ile emprenye edilmiş ve 200 °C'de ısıl işlem uygulanmış örneklerde tespit edilmiştir.

In this study, the effect of impregnation with natural extracts on decay resistance and color change of pine and beech wood was analyzed. Flowers of Rhododendron luteum and Rhododendron ponticum plants were extracted according to the decoction method and aqueous solutions were prepared at different concentration levels (2 %, 4 % and 7 %). In addition, ferrous sulfate, copper sulfate and aluminum sulfate mordants were added to the solution to improve the properties of the extracts. Then the wood specimens were impregnated with the prepared solutions. The results indicated that the effect of plant species on the mass loss of specimens exposed to T. versicolor (white-rot fungus) was insignificant. Non-mordant extracts had a slight effect on the mass loss of the specimens. However, in pine and beech specimens impregnated with mordant-added (especially ferrous sulfate-added) extracts, mass loss was significantly reduced and resistance to fungal rot was almost completely achieved. The concentration level did not have a significant effect on the mass loss of specimens treated with mordant-added extracts. After impregnation, the L* value of all specimens (especially those treated with ferrous sulfate-added extracts) decreased and the specimens darkened. The a* and b* values increased in specimens treated with non-mordant and aluminum sulfate-added extracts and these specimens tend to have a red-yellow color. The a* value decreased and the b* value increased in wood specimens treated with copper sulfate-added extracts. The green-yellow color trend of these specimens increased. Both the a* and b* values of the specimens treated with ferrous sulfate-added extracts decreased and the green-blue color tendency increased in these specimens. The increase in the concentration level positively affected the determined color changes. The total color change (ΔE*) was higher in wood specimens (especially pine) treated with ferrous sulfate-added R. ponticum extracts., U istraživanju je analiziran utjecaj impregnacije borovine i bukovine biljnim ekstraktima na otpornost na propadanje. Cvjetovi biljaka Rhododendron luteum i Rhododendron ponticum ekstrahirani su metodom dekocije te su pripremljene vodene otopine različitih koncentracija (2 %, 4 % i 7 %). Osim toga, otopini su dodani fiksatori željezov sulfat, bakrov sulfat i aluminijev sulfat radi poboljšanja svojstava ekstrakata. Zatim su uzorci uzoraka izloženih djelovanju T. versicolor (gljivi bijele truleži) bio neznatan. Ekstrakti bez fiksatora imali su mali učinak na gubitak mase uzoraka. Međutim, znatno je smanjen gubitak mase uzoraka borovine i bukovine impregniranih ekstraktima s dodatkom fiksatora (osobito željezova sulfata), a postignuta je gotovo potpuna otpornost na gljive truležnice. Koncentracija otopine nije imala znatniji utjecaj na gubitak mase uzoraka zaštićenih ekstraktima s dodatkom fiksatora. Nakon impregnacije smanjila se L* vrijednost svih uzoraka (posebno onih zaštićenih ekstraktima s dodatkom željezova sulfata) i uzorci su potamnjeli. Povećale su se vrijednosti a* i b* uzoraka impregniranih ekstraktima bez dodatka fiksatora i ekstraktima s dodatkom aluminijeva sulfata i ti su uzorci poprimili crvenožutu boju. Vrijednost a* uzoraka drva premazanih ekstraktima s dodatkom bakrova sulfata smanjila se, a vrijednost b* se povećala. Udio žutozelene komponente na tim se uzorcima povećao. Vrijednosti a* i b* uzoraka premazanih ekstraktima s dodatkom željezova sulfata smanjile su se i povećao se udio zelenoplave komponente. Povećanje koncentracije otopine kojom su uzorci impregnirani pozitivno je utjecalo na promjenu boje. Ukupna promjena boje (ΔE*) bila je veća na uzorcima drva (osobito borovim) impregniranim ekstraktima R. ponticum s dodatkom željezova sulfata.

A typical structure of thermal spray coatings consisted of molten particles, semi-molten particles, oxides, pores, and cracks. These factors caused the porosity of sprayed coatings, leading to a significant influence on the coating properties, especially their wear-corrosion resistance. In this study, a post-spray sealing treatment of Cr3C2-NiCr/Al2O3-TiO2 plasma-sprayed coatings was carried out, and then, their corrosion properties were evaluated, before and after the treatment. For the sealing process, aluminum phosphate (APP) containing Al2O3 nanoparticles (~10 nm) was used. The permeability of APP into the sprayed coating was analyzed by SEM-EDS. The treatment efficiency for porosity and corrosion resistance of sprayed coatings was evaluated by electrochemical measurements, such as the potentiodynamic polarization and electrochemical impedance spectroscopy. The wear-corrosion resistance of the coating was examined in 3.5 wt.% NaCl circulation solution containing 0.25% SiO2 particles. The sealing efficiency was evaluated by the percentage of the treated open pores in the coating. The obtained results showed that APP penetrated deeply through the coating and the incorporation of Al2O3 nanoparticles into APP sealant improved the sealing efficiency by 20% of open pores in comparison with the sealant without nano-Al2O3. The effect of the post-treatment on corrosion protection of the sprayed coating has been discussed.

Zeolites are wide used materials in a range of processes of chemical, petrochemical, and nutritional industry. They are the active catalysts and sorbents, in particular, zeolites are characterized by high efficiency towards extraction of heavy and radioactive metals from the aqua medium. An important factor of high zeolite catalyst activity is preserving the integrity of the crystal structure. The purpose of this research was to check out the features of MOR zeolite modifications with nickel by means of low temperature nitrogen adsorption/desorption, IR-spectroscopy, and X-Ray Diffraction (XRD). Using ion exchange and following calcination the hydrogen form of zeolite was obtained. The last was impregnated by nickel in quantity of 1, 5, and 15 wt. %. The investigations of nickel-modified samples demonstrated that MOR-type zeolite was relatively resistant to the used manipulations. However, the hysteresis loops of their isotherms are observed. The last can be connected with mesoporosity appearance. The degree of zeolite destruction is found out to increase with rise of nickel content in the samples. Based on IR spectra analysis by means of checking out the ratio between intensity of bands at 560 and 440 cm-1 using Gaussian function in Origin medium the same conclusions were drawn. Crystalline structure of mordenite was confirmed by using XRD method, but minor quantitative destruction cannot be recognized without application of methods of the internal and external standards. Цеоліти широко використовують у ряді процесів хімічної, нафтохімічної, харчової промисловості. Вони є ефективними каталізаторами та сорбентами, зокрема, відзначаються високою ефективністю щодо вилучення важких та радіоактивних металів із водного середовища. Важливим фактором високої активності цеолітних каталізаторів є збереження цілісності кристалічної структури. Метою даної роботи була оцінка особливостей модифікування нікелем цеолітів типу MOR методами РФА, ІЧ-спектроскопії та низькотемпературної адсорбції/десорбції азоту. Методом іонного обміну одержано водневу форму цеоліту, на яку просочуванням нанесено нікель у кількості 1, 5 та 15 % мас. Вивчення модифікованих нікелем зразків показали, що цеоліт типу MOR виявився відносно стійким до використаних маніпуляцій. Однак, для нього спостерігається петля гістерезису на ізотермі низькотемпературної адсорбції/десорбції азоту, що свідчить про утворення мезопористості. Знайдено, що ступінь руйнування цеоліту зростає зі збільшенням вмісту нікелю у зразках. Аналогічні висновки зроблено на основі аналізу ІЧ-спектрів шляхом оцінки співвідношення інтенсивності смуг поглинання при 560 та 440 см-1 за допомогою функції Гауса в середовищі Origin. Методом РФА підтверджено кристалічну структуру типу морденіту, однак незначні кількісні руйнування визначити не вдалося без застосування методів внутрішнього стандарту та зовнішнього еталону.

International audience; The preparation step of a catalyst is of primary importance as it may govern its performance. We report here the first direct multi-elemental imaging of an alumina-supported catalyst during the maturation process. Alumina extrudate support was impregnated with a nickel nitrate solution in the presence of citric acid as an organic additive. Wet extrudates were sampled, cut in half and imaged by Laser-Induced Breakdown Spectroscopy (LIBS) for varying maturation times. Results were validated by comparison with more conventional techniques such as Raman and Magnetic Resonance Imaging. This communication demonstrates the speed of acquisition, low detection limits and multi-elemental capabilities of LIBS to provide valuable information to understand the phenomena occurring during catalyst impregnation. The proposed approach allows one to shorten drastically the analysis time (by a factor of 30) and emphasizes LIBS imaging potential as a unique characterization technique able to simultaneously monitor the distribution of the metallic precursor, organic additive and support impurities.

Natural Ca-Bentonite from Ebenebe in Anambra State, Nigeria, was successfully impregnated with Ca (NO3)2, Zn (NO3)2 and KOH and further calcined under different conditions of temperature and time using standard methods. Both the natural and impregnated bentonite clays were characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Fluorescence Spectroscopy (XRF) and Scanning Electron Microscopy (SEM) and then applied as catalysts in transesterification reaction of refined castor oil. Viscosity reduction test was used to ascertain the best catalyst for the transesterification. FTIR spectra of the activated clay catalysts show the formation of new functional groups, as the intensity of the Al-O-H stretching group (3633cm-1) of the natural clay increased with slightly higher wavelengths of 3640cm-1, 3644cm-1, 3644cm-1, 3644cm-1, 3640cm-1and 3644cm-1 for CaB2, CaB3, ZnB2, ZnB3 KB400, and KB700 catalysts respectively. XRF result identified the natural bentonite clay as Ca-bentonite clay with Ca-oxide having the most dominant component of 76.71%. XRF chemical compositions of the six activated Ca-bentonite clay catalysts when compared to the natural Ca-bentonite clay confirmed successful impregnation. The SEM images of all the prepared catalysts showed that impregnation and calcination changed the surface morphology of the natural clay. Finally, transesterification reactions of refined castor oil samples were done with 3%w/w natural and impregnated Ca-bentonite catalysts, methanol to oil ratio of 6:1, 2 hours reaction time and 65oC reaction temperature. Results obtained showed a descending order of catalyst viscosity reduction ability to be KB700 > CaB3 > CaB2 > ZnB3 >NCB > ZnB2 > KB400.

Mangium (Acacia mangium Willd.) is a fast-growing wood that is widely grown in Indonesia. The impregnation method is needed to improve the qualities of the wood. In this study, TiO2 nanoparticle (79.17 nm) was produced using the hydrothermal method. The purpose of this study was to analyze the effect of TiO2 nanoparticle impregnation on the density and dimensional stability of mangium and the effectiveness of the presence of TiO2 nanoparticle in wood in degrading pollutants. The mangium samples (2 cm × 2 cm × 2 cm) were placed inside impregnation tube. The impregnation solutions included water (untreated), 1% TiO2 nanoparticle, and 5% TiO2 nanoparticles. The samples were analyzed for density, weight percent gain (WPG) dan bulking effect (BE). Samples were also analyzed by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). TiO2 nanoparticle resulted in an increase in density, WPG, and BE-treated mangium. Based on XRD and FTIR results, TiO2 nanoparticle was successfully impregnated into mangium wood. Scanning electron microscopy–energy-dispersive X-ray spectroscopy analysis indicated that TiO2 nanoparticle covered the surface of the wood cells. The TiO2-impregnated mangium wood has a higher photocatalyst activity than untreated, indicating better protection from UV radiation and pollutants.

Fast-growing Chinese fir wood has shortfalls such as loose structure and low strength because it grows faster than natural trees. Resin impregnation is a great way to increase the strength of fast-growing fir. However, the resin used for impregnation is a kind of urea-formaldehyde resin, phenolic formaldehyde resin, melamine formaldehyde resin, and the like, which introduce harmful substances such as formaldehyde or phenolic into the wood. In this paper, Chinese fir wood was impregnated with natural shellac polymer, and the effects of impregnation variables on the mechanical properties of the wood were examined. The increase in strength in compression perpendicular to grain (SCPG) of wood samples impregnated with 15% shellac solution achieved a maximum value of 39.01%, but the modulus of rupture (MOR) was slightly reduced. The effects of the impregnation pressure, time, and their interaction were investigated by the response surface method (RSM). ANOVA analysis revealed that the impregnation pressure and time and the interaction between the two seemed to have a significant effect on ∆SCPG. Based on the response face model, the corresponding optimal parameters obtained are 1.0 MPa and 16.0 min for impregnation pressure and time, respectively. By impregnating fir wood with the above optimal conditions, the SCPG increased by 85.78%, whereas the MOR decreased by the least amount.

Birch plywood has a wide range of applications for interior and exterior use. The demand for plywood with improved fire protection properties and good visual appearance is increasing year by year. The impregnation at high pressure of the whole plywood panels is one of the options to achieve it. The aim of this study was to develop good visual looking birch plywood product for interior design purposes as well evaluate different influencing factors to reaction to fire properties of fire-retardant treated birch plywood. This study consists of three parts. At the first stage, high pressure industrially impregnated plywood properties were studied by two influencing factors – distribution of fire retardant in plywood panel plane and sanding process influence on reaction to fire performance of product. At the second stage, seven different industrial finishing systems were selected for covering high-pressure impregnated birch plywood and their effect on fire reaction performance was studied. In addition, two surface coating systems were studied on standard birch plywood substrate. At the third stage, intumescent coating consumption effect on reaction to fire performance was studied. The reaction to fire performance of birch plywood was evaluated by performing a flammability test using the Single Burning Item test according to EN 13823:2010. It was found that high pressure impregnation of plywood cannot ensure even saturation of fire retardant throughout the sheet, which significantly affects the fire performance of product. The impact of different finishing materials to reaction to fire performance has been described by the results of this research.

The properties of three types of CoMo/USY catalysts with different synthesized methods have been studied. The sequential and co-impregnation methods followed by activation using calcination and reduction process have been conducted. The properties of the catalysts were examined using Fourier-transform-infrared (FTIR) spectroscopy, X-ray diffraction (XRD) with refinement, and surface area analyzer (SAA). The FTIR spectrum study revealed the enhanced intensity of its Bronsted acid site, and the XRD diffractogram pattern verified the composition of pure metals, oxides, and alloys in the catalyst. The SAA demonstrated the mesoporous features of the catalyst. Scanning electron microscopy showed an irregular particle morphology. Additional analysis using the transmission electron microscopy indicated that the metal has successfully impregnated without damaging the USY structure.

Preservation and improvement of quality indicators of any product is an urgent scientific and practical task for current production, including products from a natural facing stone. There are no similar deposits of natural facing stone in the world. Each of them is unique in its own way. However, most natural stone deposits are characterized by natural variability of quality indicators. First of all, after processing such stones there will be differences in color tone. It is possible to give a different colour tone by chemical treatment. Currently, there are many chemical methods of processing natural stone. However, most of them are insufficiently studied. Therefore, the assessment of the effect of chemical treatment on the surface of natural stone was investigated using infrared spectroscopy. Linear regularities of change of colour indicators of natural stone depending on its initial indicators after chemical treatment on the example of Pokostivskyi granodiorite (Gray Ukraine) and Bukivskyi gabbro (Galant) are established. In addition to the colour segmentation method, infrared spectroscopy was used to assess differences in the types of natural facing stone, which showed that Pokostivskyi granodiorite (Gray Ukraine) and Bukivskyi gabbro (Galant) have the same wavelengths belonging to the common rock-forming mineral plagiarism. The change in the absorption of infrared radiation is due to the effect of cavities and volumetric scattering of rays due to the passage through the crystallized film of chemical impregnating substances. For a certain type of natural stone, the change in absorption will be greater or less when a certain type of chemical treatment is used, which indicates a strong or weak bond between the chemical impregnating substances and the surface of the natural stone, respectively.

During leather finishing the surface of leather is coated with coloured binder systems. In conventional finishing, two to five grams of dyestuff are used per square foot of leather. Due to so-called overspray, 40-60 % of dyestuff is lost. To increase resource efficiency, we examine the impregnation of dyestuff-free leather coatings using supercritical CO2 at 100 bar and 40 °C as a solvent for Solvent Red 111. The focus of the investigation is the effect of the layer thickness on the colour intensity. Furthermore, the dyestuff absorption capacity of the binder layer is determined. As result, a layer thickness of 23 µm allows the maximum achievable colour intensity. The dyestuff absorption capacity at this thickness is 35 mg of dyestuff per square foot of leather. This results in a saving potential for dyestuff of over 95 %.

Fast-growing poplar with low wood density has been generally regarded as a low-grade wood species and cannot be used as a building material due to its poor fire resistance. As the fire resistance of wood materials is positively correlated with density, combined treatment using resin impregnation, which imparts thermal resistance, and compression, which improves density, appeared to be a route toward improved combustion performance. Fast-growing poplar wood was modified with a combination of borate-containing phenol–formaldehyde resin impregnation and compression in a transverse direction at varying intensities. The effects of the combined treatment on fire resistance were then examined and discussed. Char residue morphology analysis and microscopic observations were conducted to reveal the effects and mechanism of the combined treatment on fire resistance improvement. The test results showed that fire resistance was greatly improved, including the static and dynamic bending performance at elevated and high temperatures, as well as the combustion performance. The higher the compression ratio was, the better the fire resistance of the modified wood.

In this work, we present a systematic study on the influence of Cu2+ ion concentration in the impregnation solution on the morphology, structure, optical, semiconducting, and photoelectrochemical properties of anodic CuOx-TiO2 materials. Studied materials were prepared by immersion in solutions with different concentrations of (CH3COO)2Cu and subjected to air-annealing at 400 °C, 500 °C, or 600 °C for 2 h. The complex characterization of all studied samples was performed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), reflectance measurements, Mott–Schottky analyses, and photocurrent measurements. It was found that band gap engineering based on coupling CuO with TiO2 (Eg~3.3 eV) is an effective strategy to increase the absorption in visible light due to band gap narrowing (CuOx-TiO2 materials had Eg~2.4 eV). Although the photoactivity of CuO-TiO2 materials decreased in the UV range due to the deposition of CuO on the TiO2 surface, in the Vis range increased up to 600 nm at the same time.

Silica supported sulfuric acid (SSA) has been demonstrated to be capable of effectively removing phenyl VOCs through the reaction-type adsorption mechanism. The effects of the solvent (water, ethyl acetate) used to impregnate silica gel with H2SO4 solution in order to prepare SSA adsorbents have been studied. As-prepared two series SSA(E)-x and SSA(W)-x materials (x = 1, 2, 3, 4) were characterized by TG, SEM/EDS and N2 adsorption/desorption techniques, and their breakthrough adsorption performances were evaluated from experimental and theoretical aspects. The results showed that the H2SO4 loading amounts were 2.8, 4.0, 4.8 and 5.6 mmol g−1 respectively for both SSA(E)-x and SSA(W)-x when x equaled 1, 2, 3, 4. Among them, SSA(E)-4 was found to have a higher proportion of the C-state H2SO4 than SSA(W)-4. Both SSA(E)-x and SSA(W)-x exhibited significant removal capacity of gaseous o-xylene. The reactive temperature regions were determined to be 120–170 °C for SSA(E)-4 and 120–160 °C for SSA(W)-4 with a common optimum point of 160 °C. Both SSA(E)-x and SSA(W)-x adsorbents exhibited excellent recyclability and reuse performance. Further, the series SSA(E)-x materials outperformed the series SSA(W)-x on all adsorption performance metrics, suggesting that ethyl acetate is a preferred solvent for preparing the SSA materials in phenyl VOCs removal application.

Continuous compression moulding (CCM) is an efficient process for manufacturing endless fibre-reinforced thermoplastic composites, so called organic sheets. The semi-finished products are fully impregnated and consolidated and can be thermoformed into complex 3D-geometries. Applications benefit from excellent weight-specific features as well as functional integration. Nevertheless, limited production speed and lower than acceptable manufacturing quality are still a challenge, especially with the use of high shrinkage polymers. Hence, porosities and defects due to pressure drops inside the laminate during impregnation and solidification can cause degradation in material properties. With the integration of an active adaptive pressing tool and an inline pressure measurement system, the process can be optimised towards guided impregnation and improved pressure distribution. A calculation method based on the B-factor method by Mayer has been adapted for the CCM process in order to enhance the tool design. Both, production speed as well as organic sheet quality can be improved with the optimised processing system presented in the following work.

Osmotic dehydration (OD) is a method to partially reduce moisture of food, aiming to improve the shelf life and the stability of the products. The mass transfer that occurs during this process can be enhanced with the application of reduced pressure in the first minutes of the osmotic dehydration (pulsed vacuum osmotic dehydration - PVOD). The present work aimed to study the vacuum effect on the kinetics of osmotic dehydration of vegetables (carrot, eggplant and beetroot) in terms of water loss, solids gain and water activity, in ternary solution. Moreover, mathematical modeling of experimental data obtained from the osmotic processes, was employed for correlating the mass transfer of the food product under the different conditions. An intensification of mass transfer was observed for carrot and eggplant in the vacuum treatments. This was related to their porous structure. The present work demonstrated a lack of fit of Fick’s second law for describing the dehydration kinetics of the eggplant.

Photocatalytic reduction of carbon dioxide into methanol fuel over the Ni-doped TiO2 catalyst has been investigated. The experiments were carried out in a 50 ml batch reactor under UV irradiation. Ni/TiO2 photocatalysts were prepared by an impregnation method. The properties of the catalyst were characterized by X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflectance (UV–DR). Moreover, the effect of reaction time and Ni loading on the methanol conversion were investigated. The result indicated that the maximum of methanol production was obtained after the irradiation of 3 h and slightly reduced due to the methanol oxidation process. The Ni loading catalyst showed the higher methanol concentration than that over undoped TiO2 because Ni could trap the electron during irradiation and reduce electron–hole pair recombination by the p–n junction of TiO2. The highest methanol production rate of 272. 45 μ m ol/g cat was obtained over 4% wt Ni/TiO2 catalyst, which was 20 times higher methanol production rate than that over the commercial TiO2 catalyst (P25). Moreover, the stability of catalysts could be recycled four times with high activity of CO2 reduction to methanol. Therefore, 4% wt. Ni/TiO2 catalyst, low cost, showed better potential and activity in reducing CO2 emission to the environment.

Magnetic Graphene Oxide(MGO) impregnated Di(2-Ethyl Hexyl)Phosphoric Acid (D2EHPA) (DMGO) was prepared by multi-impregnation. The structures of GO and DMGO were characterized by FT-IR, TGA, EDX, SEM, and XRD. The adsorption capacity for U(VI) from aqueous solution is 154.4 mg/g at pH 5. The essential factors that affected U(VI) adsorption such as initial pH, contact time, and temperature were investigated. The adsorption is highly dependent on the solution pH. In addition, the adsorption isotherm and thermodynamics were investigated. The adsorptions of U(VI) from aqueous solution on DMGO was fitted to the Langmuir adsorption isotherms. The adsorption of U(VI) on DMGO is remarkably improved byGO impregnated with D2EHPA. Thermodynamic parameters further show that the sorption is an endothermic and spontaneous process. DMGO is a powerful promising sorbent for theefficient removal of U(VI) from aqueous solutions.

Some stages of the finishing technology of high thickness and surface density textiles such as drying and thermal fixing have a number of problems, especially when using solutions of aqueous polymer dispersions as an application. This manifests itself in the form of migration of particles of the dispersed phase to the surface of the textile web under the influence of heat flow and film formation. This results in deterioration of the operational and special properties of the finished product. A solution to this problem is to use ultra-high frequency electromagnetic radiation for drying. The process of drying and thermal fixing textile woven fabrics with surface density of 460 g/m2 from viscose filaments in the medium of electromagnetic radiation of microwave range was investigated. Structural analysis of the sections of the obtained fabrics proved the effectiveness of the new heat treatment method compared to convective drying. Некоторые этапы технологии заключительной отделки текстильных материалов большой толщины и поверхностной плотности – сушка и термофиксация – сопряжены с рядом проблем, особенно при использовании в качестве аппрета растворов водных дисперсий полимеров. Проявляется это в виде миграции частиц дисперсной фазы к поверхности текстильного полотна под действием теплового потока и образованию пленки. Это приводит к ухудшению эксплуатационных и специальных свойств готового изделия. Решением данной проблемы является использование для сушки электромагнитного излучения сверхвысокочастотного диапазона. Проведены исследования процесса сушки и термофиксации текстильных тканых полотен поверхностной плотностью 460 г/м2 из вискозных нитей в среде электромагнитного излучения СВЧ-диапазона. Структурный анализ срезов полученных полотен доказал эффективность применения нового способа термообработки в сравнении с конвективной сушкой.

The rise in global energy demand has encouraged exploring into other innovative methods of generating renewable fuels from different forms of waste. Due to its accessibility, culinary used vegetable oil is regarded as a potential source for profitable production of biodiesel. In the present study, the viability of producing biodiesel from used vegetable oil (UVO) by utilizing CaO catalyst (derived from the calcination of chicken eggshell and impregnated with KNO3 and NaNO3) was studied. Higher yield of biodiesel was obtained at methanol/oil mole ratio of (9–10) and CaO catalyst concentration of (2.0–3.0) wt/wt% Oil, for the three forms of catalyst used. Also, higher yield of biodiesel was obtained when CaO with impregnated KNO3 was used, followed by the operation involving CaO with impregnated NaNO3. At optimum conditions of methanol/oil mole ratio of 9 and catalyst concentration of 2.4 wt/wt% Oil, the yields of biodiesel obtained were 90% (for unimpregnated catalyst), 92% (using CaO impregnated with NaNO3) and 95% (using CaO impregnated with KNO3). The higher biodiesel yield obtained for CaO impregnated with KNO3 (compared to the yield from CaO impregnated with NaNO3) could be traced to a more reactive nature of potassium and arrangement of electrons of both potassium and sodium. The results of the tests and analysis on biodiesel properties reveal that quality biodiesel were produced from the three forms of catalyst used. This is because, each of the values of the properties considered falls within the ASTM standard.

The paper presents a new test stand for ivestigating the rate of penetration of transformer oil through electrotechnical pressboard. The stand consists of a pipe, to the lower end of which is glued a pressboard plate. The pipe is filled with insulating oil. A mirror is placed under the plate, which directs its image to the lens of the camera, which takes a series of photographs at a given time interval. After being saturated with the insulating oil, the pressboard changes colour from light to dark yellow. The absorbing time is defined as the time in which a dark yellow spot appears on the lower light surface of the pressboard after the pipe is filled with oil.A new way of determining capillary diameters has been developed when the number of capillaries is unknown and the volume of liquid flowing through them is not measurable. The distribution of the times of penetration of transformer oil through 2 mm thick electrotechnical pressboard was determined, the values of which range from about 220 min to about 550 min. It was found that the radii of capillaries through which the insulating oil penetrates are within the range from about 45 nm to about 70 nm. Due to the structure of the pressboard, which consists of cellulose fibres, arranged more or less tightly, there are capillaries in the structure of the board, each of which has sections of varying lengths of radii. This means that short sections of a single capillary can have radii both smaller than 45 nm and larger than 70 nm.The developed stand and the new analysis method can be used for testing various porous materials for penetration by various liquids.

Doğu Karadeniz Bölgesinde doğal olarak yetişen ve orman ürünleri sanayinde yoğun olarak kullanılan doğu ladini (Picea orientalis L.) ve doğu kayını (Fagus orientalis L.) odun örnekleri silikon bazlı emprenye maddelerinin %10 ve %50’ lik konsantrasyonlarında dolu hücre yöntemi ile emprenye edilmiş ve emprenye sonrasında odun özelliklerinde meydana gelen değişiklikler bazı fiziksel ve mekanik test yöntemleri ile belirlenmeye çalışılmıştır. Çalışmada kullanılan silikonlar ticari bir firmadan temin edilmiştir. Fiziksel özelliklerden yoğunluk, mekanik özelliklerden liflere paralel basınç direnci ve dinamik eğilme (şok) direnci testi yapılmıştır. Çalışmadaki tüm testler 10 tekrarlı yapılmış olup yoğunluk ve liflere paralel basınç direnci testleri için 2x2x3 cm, şok direnci için 2x2x30 cm boyutlarında örnekler kullanılmıştır. Sonuç olarak emprenye edilen örneklerin yoğunluk ve liflere paralel basınç direnci, kontrol örneklerine yakın bulunmuştur. Ancak emprenye edilen örneklerin şok direncinde azalmalar olduğu gözlenmiştir. Dinamik yüklerin etkisinde kalan köprü, merdiven, gibi yerlerde silikon bazlı emprenye maddeleriyle emprenye edilen ahşabın kullanılmaması önerilmektedir.

The data of studies on the effectiveness of impregnating Aquastat waste generated as a result of the development of limestone-shell rock deposits are presented. As a result of sand impregnation, the water absorption coefficient as a result underwent a significant decrease from 7 to 17 times, while the water absorption coefficient decreases from 32.5% for the initial to 1.9% impregnated. Even treatment with low concentrated (ρ = 1.17 g / cm3) calcium polysulfide solution made the water absorption coefficient to decrease to a value of 4.5%. As a result of impregnation of crushed stone from limestone-limestone with a solution of calcium polysulfide, the water absorption coefficient decreases from 25.0% for untreated to 5.2% for treated, and the decrease in the coefficient of water absorption is greater for concentrated solutions. It was found that a solution density of 1.24 g/cm3 is sufficient to reduce the water absorption coefficient to a value of 5.2%, the same as for a density value of 1.35 g/cm3. Comparison of the results of impregnation with «Aquastat» solution and sulfur melt showed that as a result of treatment with sulfur melt, the water absorption coefficient decreases by 13.3 and strength increases by 2 times, and as a result of impregnation with «Aquastat» solution decreases by 4.62%, strength increases by 1.35 times. Despite the high efficiency of sulfur melt processing, such treatment has drawbacks associated with the use of autoclave technology and high temperatures. The results of the modification of sand and crushed stone from shell rock by impregnating it with the «Aquastat» solution, a significant decrease in the water absorption parameter, an increase in compressive strength, revealed the possibility of using impregnated crushed stone as the layer material lying at the base of the road structures of local roads in the form of crushed stone and sand instead of the more expensive imported crushed stone.

A set of Cu-ZSM-5 samples (Si/Al = 25) was synthesized by wetness impregnation, aqueous phase ion exchange and solid-state ion exchange, SSIE. Copper(II) acetate was used as precursor during both wetness impregnation and aqueous phase ion exchange to prepare excessively-exchanged samples (i.e. Cu/Al > 1), whereas SSIE was carried out by sublimating copper(I) chloride. Additionally, a Cu-ZSM-5 sample with extremely low Al content (Si/Al = 500) was prepared by impregnation. The samples were tested in the catalytic decomposition of N2O, with the aim of studying possible effects of the preparation technique on the isothermal oscillatory behavior of the reaction rate in a series of tests carried out by varying both the temperature and the residence time. The SSIE sample led to a non-oscillating system, whereas the highest Cu content samples prepared by the two aqueous procedures exhibited clear oscillations of the reaction rate. The Cu-ZSM-5 with Si/Al = 500 was quite inactive, but, surprisingly, gave rise to oscillations of both unconverted N2O and produced O2 concentrations at the reactor outlet. A combined IR spectroscopy and H2-TPR study showed the role of oligomeric CuxOy species with extra-lattice oxygen close to the Al atoms on the observed oscillations. Such species are much more abundant in the samples prepared by either impregnation or ion-exchange, when Cu/Al > 1. In contrast, the sample prepared by SSIE resulted to be rich in Cu+ isolated species, active for the reaction, but not inducing oscillation.

To avoid the proneness to degradation due to coking in the operation of solid oxide fuel cells (SOFCs) directly running on methane (CH4) fuels, a modified porous anode of the Ni1&minus, XCoX/YSZ (yttria-stabilized zirconia) cermet prepared by an impregnation method is presented. The influence of the Co alloying content on the cermet microstructure, SOFC characteristics, and prolonged cell performance stability has been studied. Co was incorporated into Ni and formed a solid solution of Ni1&minus, XCoX alloy connected with the YSZ as the cermet anode. The porous microstructure of the Ni1&minus, XCoX/YSZ cermet anode formed by sintering exhibited a grain growth with an increase in the Co alloying content. The electrochemical performance of the cells consisting of the Ni1&minus, XCoX/YSZ cermet anode, the YSZ electrolyte, and the LSM (La0.8Sr0.2MnO3) cathode showed an enhancement by the Ni1&minus, XCoX impregnation treatment for the respective supply of H2 and CH4 to the anode. The cell using the Ni0.75Co0.25/YSZ cermet anode (the Ni0.75Co0.25 cell) showed the highest cell performance among the cells tested. In particular, the performance enhancement of this cell was found to be more significant for CH4 than that for H2, a 45% increase in the maximum power density for CH4 and a 17% increase for H2 at 750 &deg, C compared with the performance of the cell using the Ni/YSZ cermet anode. Furthermore, the prolonged cell performance stability with a continuous CH4 supply was found for the Ni0.85Co0.15 and Ni0.75Co0.25 cells at least for 60 h at 750 &deg, C. These enhancement effects were caused by the optimum porous microstructure of the cermet anode with the low anodic polarization resistance.

This study investigated the effect of pre-impregnation with water-repellent agents on the hygroscopicity and dimensional stability of fir (Abies bornmulleriana Mattf.) and aspen (Populus tremula L.) woods. After pre-vacuum treatment, the samples were impregnated at atmospheric pressure with paraffin, linseed oil and styrene, and then densified at compression rates of 20 % and 40 % at 120, 150 and 180 °C. The results showed that water repellents significantly affected the hygroscopicity and dimensional stability of the densified wood samples. Compression recovery rate (CRR), thickness swelling (TS), equilibrium moisture content (EMC), and water absorption (WA) values of the densified samples decreased with impregnation pretreatments. The linseed oil treatment gave more positive CRR and TS results than paraffin. Lower EMC and WA values were found in the paraffin-treated samples. However, the most successful results for all tested properties were determined in the styrene pretreated samples in which hygroscopicity decreased and dimensional stability increased (especially for aspen) due to increases in the compression rate and temperature related to densification conditions. In the styrene pretreated samples, the high temperature (180 °C) and compression rate (40 %) significantly reduced CRR, TS, EMC and WA, total dimensional stability was nearly achieved and the water repellent effectiveness was close to 100 %., U radu se prikazuje istraživanje utjecaja predimpregnacije drva jele (Abies bornmulleriana Mattf.) i jasike (Populus tremula L.) vodoodbojnim sredstvima na njihovu higroskopnost i dimenzijsku stabilnost. Nakon vakuumske obrade uzorci su pri atmosferskom tlaku impregnirani parafinom, lanenim uljem i stirenom. Zatim je provedeno ugušćivanje sa stupnjevima ugušćenja 20 i 40 % pri temperaturi od 120, 150 i 180 °C. Rezultati su pokazali da vodoodbojna sredstva značajno utječu na higroskopnost i dimenzijsku stabilnost uzoraka ugušćenog drva. Predimpregnacijom uzoraka smanjili su se stupanj povrata ugušćenja (CRR), debljinsko bubrenje (TS), ravnotežni sadržaj vode (EMC) i apsorpcija vode (WA) ugušćenih uzoraka. Postupkom s lanenim uljem smanjeni su povrat ugušćenja i debljinsko bubrenje u usporedbi s postupkom impregnacije parafinom. Na uzorcima impregniranim parafinom utvrđene su niže vrijednosti ravnotežnog sadržaja vode i apsorpcije vode. Međutim, najbolji rezultati svih istraživanih svojstava dobiveni su na uzorcima impregniranima stirenom, kojima se zbog povećanja brzine i temperature ugušćivanja smanjila higroskopnost i povećala dimenzijska stabilnost (posebice drva jasike). Na uzorcima impregniranima stirenom i ugušćenima pri temperaturi od 180 °C sa stupnjem ugušćenja 40 % znatno su se smanjili stupanj povrata ugušćenja, debljinsko bubrenje, ravnotežni sadržaj vode i apsorpcija vode te je postignuta gotovo potpuna dimenzijska stabilnost i učinkovitost odbijanja vode (blizu 100 %).

Jabon (Anthocephalus cadamba) is a fast-growing wood with low quality due to its low density and strength. The quality can be increased by modifying the wood through impregnation with various chemical compounds. In this study, jabon was impregnated with a solution of Fe and immersed in a strong base (NaOH) or a weak base (NH4OH) to form magnetite (Fe3O4) in-situ. This study analysed the use of NaOH and NH4OH in synthesising magnetic jabon wood and evaluated the wood’s characteristics. The impregnation process began with a vacuum of −0.5 bar for 0.5 h and then a pressure of 1 bar for 2 h. The samples subsequently underwent assessment of their dimensional stability, density, and characteristics. The results showed that impregnation with Fe solution followed by NaOH or NH4OH significantly affected the density and dimensional stability of the wood. The polymer weight gain was higher with NaOH, while the anti-swelling efficiency was higher with NH4OH. The density and bulking effect were increased, but the water uptake was decreased. Fourier transform infrared analysis showed the successful synthesis of magnetite. Scanning electron microscopy–energy-dispersive X-ray spectroscopy analysis revealed that magnetite covered the vessel fibre cell walls, and vibrating sample magnetometry analysis showed significant magnetic properties of the wood.