PRODUCTION OF POROUS GLASS-CRYSTALLINE MATERIALS BASED ON GLASS CULLET AND CONVERTER SLAG

The study conducted the research aimed to obtaining a porous glass-crystalline materials based on glass cullet and converter slag, which was used as a gas-forming additive. In this work, the chemical and phase compositions of the studied slag were analyzed, and a differential thermal analysis of its sample was carried out. Converter slag was added to the composition of the masses in an amount of 2.5 to 30 wt%, the rest was glass cullet. Вurning of the samples was carried out in the temperature range of 850-925 ° C. For the samples under study, using a sand volumetric meter, the volume was determined and the swelling coefficient was calculated, the compressive strength was determined, and the type of structure, which depends on the average diameter of the prevailing pores, was analyzed. The dependence of the swelling coefficient of the investigated materials on the burdening composition and burning temperature has been established. To obtain porous materials with a swelling coefficient of 2.16-2.67 and uniform fine-porous structure (predominant pore size less than 0.5 mm), it is optimal to introduce converter slag into the composition of the masses in an amount of 10-15 wt%, and the recommended temperature range their burning 850-900 ° C. Analysis of the phase composition of the materials obtained indicates the presence of wollastonite as the main crystalline phase, which, due to the acicular structure of the crystals, has a reinforcing effect and contributes to an increase in strength characteristics. The developed porous glass-crystalline materials can be used as thermal insulation and aggregates in lightweight concrete.

Study of the Swelling of a Composite Based on Argan Nut, Urea-Formaldehyde and Water as a Non-Polluting Solvent

In the center and southwest of Morocco, there is an endemic tree «Argania Spinosa» known as the ironwood. The miraculous product of this millenary tree is argan oil. Known for its therapeutic and cosmetic properties. Only 20% of the fruit of the argan tree is intended for the manufacture of argan oil while the shell, which represents 80%, remains an unexploited resource. This hull, which is sold by farmers at low prices, is used as fuel for baths and Moorish bakeries. In order to value the shells; first, we sort, grind and sieve them. Second, we bind the particles into adhesive. Three biomaterials are based on three particle sizes of shell grains. The designed particles are bound with an adhesive powder that is produced from a pre-catalyzed urea-formaldehyde resin. Moreover, the water used is a non-polluting solvent. The biomaterials and two samples of Red and Beech Wood were immersed in water for 15 days, with mass measurements that were done on a daily basis. It was concluded that the swelling coefficient of the large distribution of biomaterial is smaller than the small distribution of biomaterial. However, Red and Beech Wood have the highest coefficient.

Development and optimization of fire-protective coating composition based on epoxypolymers

The object of research is intumescent fire retardant coatings based on epoxy resins. The research is aimed at the development of mathematical models of the dependence of the swelling rate of intumescent fire retardant coatings on their composition. Considering the complexity of the processes during the formation of a protective carbon layer, it is advisable to select the optimal ratio of the components of an intumescent fire retardant coating experimentally, followed by the construction of mathematical dependences of the swelling ratio on the coating composition. Therefore, experimental studies aimed at developing and optimizing the composition of an intumescent fire retardant coating based on epoxy polymers are an important task. The studies were carried out in accordance with the theory of planning experiments with the construction of an orthogonal compositional plan of the second order. A linear swelling factor was chosen as the response function. Compositions based on the ED-20 epoxy oligomer, cured with polyethylene polyamine and filled with ammonium polyphosphate, aluminum hydroxide, and graphite additive were used for the study. Based on the results of processing the experimental results, a regression equation was obtained and response surfaces were constructed that describe the dependence of the linear swelling coefficient Cs of an intumescent composition based on an epoxy oligomer on the content of ammonium polyphosphate, aluminum hydroxide and graphite additive. A complex relationship is shown between the content of components and the linear swelling coefficient Cs with different ratios of the components. The optimum by the linear swelling coefficient (Cs=68.1) content of the components in the epoxy polymer was determined, amounting to 20 wt. including for ammonium polyphosphate, 15 mass parts including for aluminum hydroxide and 3 mass parts for the graphite additive. However, with such a ratio, the «self-extinguishing» condition is not met (Cs=27 %). Filling the composition with ammonium polyphosphate in an amount of 26.3 mass parts including, aluminum hydroxide 25 mass parts and 3.5 mass parts including graphite additives allows to get an intumescent fire retardant coating with a swelling ratio Cs over 63 and a reduced level of flammability (Ci=31 %)

Thermodynamic Study of Fire-Protective Material

The paper considers the material for the protective coating of building structures made of wood. The possibility of chemical processes occurring in the material leading to its expansion has been studied. The coefficient of expansion of the material when heated is practically established. It has been established that the material can swell, both under the influence of flame and when the temperature rises at a low speed. Swelling coefficient at the same time it reaches 8. The temperature range of swelling is 150–250 С, which is confirmed by thermodynamic calculations and experimentally. The temperature at which the material begins to swell is lower than the temperature of thermal destruction of wood.

NANOCOMPOSITE MATERIALS FOR CORROSION PROTECTION OF PIPELINES

Polymer coating materials are used to protect inter-mine pipelines from corrosion. The presented article proposes new polymer-based nanocomposite materials for corrosion protection of pipelines. Keywords: polymer-based coating material, nanofiller, swelling coefficient.

Effect of Lentil’s Variety and Cultural Farming System on Nutritional Value and Physicochemical Sensory Properties as Related to Human Daily Coverage

The aim of this study is to determine if there is any influence of lentil variety and environment of cultivation in the chemical composition of seeds originating from organic and conventional farming systems. Particularly, an evaluation was made on the physicochemical properties of three lentil cultivars (‘Thessalia’, ‘Dimitra’, ‘Samos’) and also the effect of farming system towards the composition of seeds to be assessed for discovering the tendency which specific cultivar or farming system are most preferable for the consumers. For the evaluation of the physicochemical properties of lentil seeds: (a) Seed density, (b) Hydration coefficient, (c) Swelling coefficient, (d) pH and (e) Content in macro- and micronutrients (total nitrogen, phosphorus, potassium, calcium, magnesium, iron, zinc, manganese, and boron), were estimated. Multivariate statistical analysis was applied for every characteristic in order to determine similarities/ differences among the cultivars in both organic and conventional farming systems. In addition, Analysis of Variance (ANOVA) and Principal Component Analysis (PCA) were conducted. Regarding the three cultivars under evaluation, cv. ‘Dimitra’ is superior especially in the organic environment, followed by cv. ‘Thessalia’, whose nutritional value increases under organic farming conditions. While ‘Samos’ exhibited a slightly better performance under conventional conditions. Based on the results of this research, the interaction between the lentil cultivar and the cultivating environment can influence the nutritional value and the physicochemical properties of lentil’s seeds.

SWELLING OF THE SUBCUTANEOUS INTERSTITIUM UNDER THE INFLUENCE OF ISONIAZID AND DIFFERENT PH LEVELS

The article deals with the issues of interstitial conductivity for isoniazid and saline solution with different pH levels. Experimental studies were conducted to substantiate and explain the mechanisms of effectiveness of indirect endolymphatic drug administration. At the present stage, lymphotropic administration of anti-tuberculosis drugs occupies a worthy place in the complex therapy of patients with pulmonary and extrapulmonary tuberculosis. Lymphotropic therapy is an etio-pathogenetic method of treating patients and consists of regional subcutaneous injections of medicinal solutions with the use of lymphotropy factors, among which it is important to create an active functioning of the interstitial zones of lymphotropic administration, which determines the flow of drugs into the lymphatic channel. The influence of acidification and alkalinization of the medium on the hydrophilicity of the interstitium of the subcutaneous tissue of the parasternal zone, armpit, and interdigital spaces was studied. As incubation solutions, saline solution with pH 6.9, pH 7.4, pH 6.0 and 10% isoniazid solution (10%H) were used. It was found that the interstitial subcutaneous tissue of the lymphotropic injection zones is characterized by different intensity of swelling, which is probably due to the morphological features of the fiber, different content of loose connective and adipose tissues in it. The swelling coefficient is regulated by the pH level of incubation solutions and the chemical structure of the administered lymphotropically medicinal substance. Features of interaction between interstitial lymphotropic points and the drug should be taken into account when prescribing indirect endolymphatic therapy schemes. It is likely that the pH of the administered solutions must be maintained at the level of the physiological norm (7.4). Isoniazid in the lymphotropic points creates a depot that is more pronounced in the parasternal region.

Evaluation of the hygroscopicity and dimensional stability of silicone oil treated wood

Wood is a renewable natural lignocellulosic material. However, its hygroexpansion characteristics dramatically shorten its service life, and limit its application. In this study, wood was treated in a silicone oil bath at different temperatures to improve its dimensional stability. Results demonstrated that the silicone oil treatment decreased the tangential swelling coefficient by 13% when treated at 80 °C and by 34% when treated at 160 °C and the radial swelling coefficient by 12% when treated at 80 °C and by 49% when treated at 160 °C. Also, the moisture absorption was reduced by the treatment.

Effect of chemical modification on dimensional stability of Pinus radiata D. Don using acetic anhydride

Chemical modification is used to efficiently improve some properties of wood to make it suitable for specific end uses. Modification using acetic anhydride (AA) is found suitable to make the wood more stable dimensionally. Pinus radiata wood samples treated with pyridine catalyzed AA were exposed to four different treatment methods comprising vacuum dipping and full cell method (cured with and without chemical). Physical properties like weight percentage gain (WPG), bulking coefficient, swelling coefficient (S) due to the chemical, water absorption and anti-swelling efficiency (ASE) were assessed for a comparative analysis. Results indicated a significant reduction in water absorption of acetylated wood. The swelling coefficients of all the treatments were found in the range of 3.86–4.96, which was twice to three times less than in the control (11.72) attributing 55–64% improvement in dimensional stability. Samples treated with full cell method and cured in the chemical mixture showed minimum swelling coefficient and best anti-swelling efficiency. All the four treatment methods chosen for the study returned significantly better dimensional stability as compared to untreated wood.