Tired Research Articles

Technology for the production of road bitumen modifier using aluminosilicate microspheres extracted from ash and slag energy waste

The results of research on the development of technological solutions for the production of a new rubber-bitumen binder for asphalt concrete based on the use of industrial waste: used car tires, used car oil and microdispersed aluminosilicate spherical particles obtained from the processing of ash and slag waste (ASW) from thermal power plants are presented. The proposed technological solutions make it possible to obtain high-quality polymer additives for modifying the properties of road bitumen. The elements of novelty of the developed approach include the use, to obtain a granular modifier, of micro-sized hydrophobized aluminosilicate spheres, which are extracted as an additional product during the complex processing of ASW. The positive economic efficiency of technological solutions is ensured by the use of large rubber crumb (more than 8 mm) or rubber chips, their devulcanization together with hydrocarbon fractions of used engine oil and petroleum bitumen at a given temperature to form a gel-like mass, which is further subjected to mechanical grinding in a mill.

PENGARUH PENGUNGKAPAN ENTERPRISE RISK MANAGEMENT DAN KUALITAS LAPORAN KEUANGAN DENGAN UKURAN PERUSAHAAN SEBAGAI VARIABEL MODERASI PADA PERUSAHAAN PENERIMA CORPORATE IMAGE AWARD

This study aims to determine the effect of enterprise risk management disclosure on the quality of financial reports in companies receiving corporate image awards. This research was conducted on companies receiving the Corporate Image Award in the categories of national airlines, car tires, two-wheeled automotive, four-wheeled automotive, coal mining, oil & gas mining, and cement for the 2015-2019 period. This study uses purposive sampling technique and secondary analysis using quantitative methods. This observation uses the random effect method and multiple linear regression analysis which is used to test the hypothesis. The results of this study indicate that the disclosure of enterprise risk management has a negative effect on the quality of financial statements, and firm size can strengthen the effect of using enterprise risk management disclosures on the quality of financial statements.

Сomputational approach to thermal-stressed state modeling of tire based on the algorithm of its self-heating analysis. Part 2 – Practical results of applying the approach

Elastomers and their composites are widely used in modern innovative technology: for the production of aviation and automobile tires, anti-vibration elements (rubber, rubber-metal springs), dampers, elastomeric bearings. Also they are used in shaft suspensions, as spacers between structural parts, supporting parts and fasteners. Elastomeric elements of structures have a high dynamic load, in particular of a cyclic nature, which is accompanied by the formation of hysteresis loops and, as a result, the occurrence of the phenomenon of self-heating. An increase in temperature in the middle of materials causes significant changes in their mechanical properties, reduces strength characteristics, accelerates aging and degradation processes, and has a significant impact on fatigue processes. In addition, an increase in temperature causes an additional thermal stress state, capable of significantly changing the qualitative picture of the structure's deformation characteristics' distribution. Thus, the purpose of this study is development of approach to assessing the thermal stress state of structures made of elastomeric materials for the possibility of further analysis of its influence on the structure work as a whole. The appropriate approach was built on the basis of numerical modeling of thermal and deformation processes which takes place into the structure during operation. The proposed approach includes several related calculations by using FEM and is based on the fundamental approaches of the theories of elasticity and viscoelasticity, thermal conductivity and thermo-elasticity. Thus, the article presents an approach to the analysis of the thermal stress state of structural elements under operating conditions. This approach was applied to determine the thermo-strain-stress characteristics of a pneumatic tire and corresponding pictures of its distribution were obtained.

Techno-economic and carbon dioxide emission assessment of carbon black production

The over 15 million metric tonnes of carbon black produced annually emit carbon dioxide in the range of 29–79 million metric tonnes each year. With the renaissance of carbon black in many new renewable energy applications as well as the growing transportation sector, where carbon black is used as a rubber reinforcement agent in car tires, the carbon black market is expected to grow by 66% over the next 9 years. As such, it is important to better understand energy intensity and carbon dioxide emissions of carbon black production. In this work, the furnace black process is studied in detail using process models to provide insights into mass and energy balances, economics, and potential pathways for lowering the environmental impact of carbon black production. Current state-of-the-art carbon black facilities typically flare the tail gas of the carbon black reactor. While low in heating value, this tail gas contains considerable amounts of energy and flaring this tail gas leads to low overall efficiency (39.6%). The efficiency of the furnace black process can be improved if the tail gas is used to produce electricity. However, the high capital investment cost and increased operating costs make it difficult to operate electricity generation from the tail gas economically. Steam co-generation (together with electricity generation) on the other hand is shown to substantially improve energy efficiency as well as economics, provided that steam users are nearby. Steam co-generation can be achieved via back-pressure steam turbines so that the low-pressure exhaust steam (∼2 bar/120 °C) can be used locally for heating or drying purposes. Furthermore, the potential of utilizing hydrogen to reduce carbon dioxide emissions is investigated. Using hydrogen as fuel for the carbon black reactor instead of natural gas is shown to reduce the carbon dioxide footprint by 19%. However, current prices of hydrogen lead to a steep increase in the levelized cost of carbon black (47%).

PROCESSING OF LIQUID HIGH-ENERGY PRODUCTS WITH THE PRODUCTION OF GAS MIXTURES OF A GIVEN COMPOSITION

The article considers the problem of using waste as an energy resource. The possibility of processing liquid carbon-containing waste, which is formed during the processing of agricultural products, the use of fats in the food industry and oils in transport, is analyzed. An analysis of the volumes of such waste is presented. It is shown that sunflower processing is accompanied by the formation of about 7,000 tons/year of liquid carbon-containing waste. Technological processes of food industry generate about 1,000 tons of such waste per year. A significant source of waste generation is motor vehicle companies, the total resource of which for the introduction of competitive processing technology is currently about 100,000 tons of olives. A promising resource source for the proposed technology is the process of thermal destruction of used automobile tires, of which 250–300 thousand tons are generated annually in Ukraine. Possibilities of introducing the technology of thermal decomposition of liquid carbon-containing substances of various origins, as components of waste, to create gaseous products of a given composition with further use in the chemical industry and replacement of natural gas are considered. The thermal decomposition of hydrocarbons with stabilization of the process due to the introduction of a high-temperature plasma discharge source into it is among the most promising methods of performing such a task. The results of the development of the methodology for the analytical study of the composition of gaseous fuels are presented. The concept and schematic diagram of the experimental stand are presented. The results of test studies are presented. Bibl. 15, Fig. 5, Tabl. 5.

CONVERSION OF CARBON-CONTAINING RAW MATERIAL USING PLASMA TECHNOLOGIES

The state of development of plasma gasification technologies of carbon-containing raw materials in Ukraine is analyzed. It is shown that despite some pessimistic domestic assessments of the prospects for their development, the state of research and development in this field at the global level indicates the inevitable breakthrough directions for the development of such technologies and, first of all, in the field of hydrogen energy. In particular, this concerns the prospects of using such difficult-to-process raw materials for hydrogen production as, for example, sewage sludge or worn automobile tires. This will create an additional powerful effect from their implementation, bearing in mind the solution of complex environmental problems of modern Ukraine. The experimental part of this work is devoted to the study of the prospects of such processing, using the example of a laboratory version of a plasma chemical reactor, made according to the scheme of the process of inverted gasification of solid organic raw materials with the introduction of a plasma jet into the pyrolysis zone. The output of hydrogen depended on the raw material: the lowest one was from sewage sludge pellets, and the highest one was from rubber crumb of worn automobile tires; in the case of gasification of a mixture of sewage sludge pellets and rubber crumb, an intermediate value of this indicator was observed. It is important that the output of hydrogen was determined not so much by its content in the raw material, but by the reactivity of the latter, which also corresponded to the degree of use of water vapor. The level of reactivity determined the degree of use of water vapor in the case of pellets up to 29 %, and rubber crumb up to 56 % and, accordingly, the chemical efficiency of gasification reached 39 % and 55 %. It follows from the results of the research that in the conditions of relatively low temperatures in the experimental reactor, the mixing of pellets of sewage sludge and rubber crumb does not create a synergistic effect of advantages regarding the energy efficiency of the process. Bibl. 58, Fig. 4, Tab. 4.

Исследование физико-механических свойств материалов балластной призмы для скоростного и высокоскоростного движения

Purpose: To substantiate the relevance of conducting research on the properties of ballast materials. To describe the methodology for conducting laboratory tests and present the results of a study of the physical and mechanical properties of ballast materials for higher-speed and high-speed train traffic. To propose the design of a ballast section using used car tires. Methods: Carrying out laboratory tests of samples of gravel from basalt, granite and gabbro-diabase for abrasion in an abrasion-tester and for impact resistance in a PM drop-testing machine. Results: The weight loss has been determined after tests for abrasion in an abrasion-tester and after tests for impact strength on a drop-testing machine. The lowest weight loss has been recorded for a sample of basalt, an intermediate weight loss has been observed for a sample of gabbrodiabase, and the highest - for crushed granite. Practical significance: Basalt rocks have the lowest mass loss in both abrasion-tester and impact tests compared to gabbro-diabase and granite. The authors have proposed a variant of the ballast section design and experimentally substantiated the choice of ballast material for this design. The results obtained can be used to substantiate the choice of ballast material in the design and construction and in modeling the performance of ballast in the track.

MODERN METHODS OF MANUFACTURING SYNTHETIC RUBBER USED FOR THE PRODUCTION OF RUBBER PRODUCTS FOR WEAPONS AND MILITARY EQUIPMENT

The material of the tire in contact with the road and areas adjacent to it is subject to bending, compression, shear and stretching. Efforts change both in magnitude and direction. In the process of operation, the tire material is constantly exposed to oxygen, air and sunlight, contact with petroleum products and other materials that have a destructive effect. Taking into account the conditions of operation and work for automobile tires and rubber products used in the OSVT of the Armed Forces of Ukraine, the following requirements are imposed:  to be elastic and soften the shocks perceived by the wheel from the road, which reduces the load on the car parts and the road, increases the comfort of the ride and the safety of the transported goods;  to ensure the safety of car movement, including at high speeds;  have the necessary strength and wear resistance, which ensure a long service life;  be inexpensive and do not require scarce raw materials for production;  to ensure high passability, longitudinal and lateral stability of the car;  work reliably in different temperature regimes of the environment;  do not make significant noise while driving the car;  ensure reliable fastening on the wheel rim, convenience and ease of installation and disassembly operations from it; do not damage the road covering; The use of automobile tires with the specified properties will provide an opportunity for high-quality performance of combat and logistical tasks. During hostilities, the wear and tear of automobile tires and other rubber products used on automobiles and special military equipment significantly increases. The main type of tire damage in during the fightiny is rolling on paved roads with energy expenditure on internal friction during overloading of the tire material (hysteresis, which leads to its heating and reduced mechanical strength), the influence of external factors, intensity, etc. An urgent problem in the Armed Forces is the ut lisation of used and damaged car tires, taking into account the conduct of various combat operations. The development of methods of utilization and recycling of tires will provide an opportunity to solve logistical and environmental problems. Keywords: fuels and lubricants, technical fluids, automobile tires, rubber, polymers, armament military and special equipment.

Prevention of Equinus Deformity after External Fixation for Open Tibia Fractures: A Comparison between Plaster of Paris Backslab and Passive Ankle Physiotherapy.

Ankle equinus deformity is a common complication of prolonged external fixator use in tibia fractures with an incidence of 15%-16%. It affects gait and may lead to foot, leg, and back problems. Treatment of equinus deformity increases the cost of treatment of open tibia fractures and increases the time spent off work. Several preventive modalities have been suggested in literature with variable success, but no standard protocol exists. The aim of this study was to determine the most appropriate method of preventing equinus deformity of the ankle joint during the management of open tibia fractures with unilateral uniplanar external fixators by comparing plaster of paris (POP) backslab application with passive ankle physiotherapy using strips of car tyre inner tubing. The study was a prospective randomised study involving patients with open tibia fractures who were managed with external fixators at the Korle Bu Teaching Hospital between April 2020 and February 2021. Patients were randomised into two groups; one group had below knee POP backslab and the other group did passive ankle physiotherapy using a strip of car tyre inner tubing. The passive ankle range of motion was measured at the beginning and after 6 weeks using a goniometer. Fifty-six participants were recruited with 29 in the POP backslab group and 27 in the ankle physiotherapy group. The median age was 35.0 years. Male-to-female ratio was 4.6:1. Motor vehicle crash contributed to over 90% with 42.9% being motorbike riders. Initial and final mean ankle measurements for the POP backslab group were 6.79° and 10.14° for dorsiflexion and 29.93° and 34.52° for plantarflexion, respectively. The ankle physiotherapy group had initial and final dorsiflexion of 7.19° and 12.85° and plantarflexion of 30.44° and 34.52°, respectively. The ankle physiotherapy group had a better range of motion (47.37°) than the POP group (40.66°) with a P value of 0.008. One participant (3.7%) from the ankle physiotherapy group had equinus deformity compared with seven (24%) from the POP backslab group, a difference which gives a P value of 0.029. Passive ankle physiotherapy with car tyre inner tube is a better and cheaper modality of preventing ankle equinus deformity and maintaining ankle range of motion.

External tire noise: Determination of timbre parameters and unpleasantness factors, with a focus on truck tires

The Leon-T project aims to reduce emissions (noise and particles) from heavy goods vehicles (HGV) tires. This study was focused on the noise emitted by tires in suburban conditions (70 km/h). Its aim was to identify the sound parameters responsible for the unpleasantness of this noise. An initial experiment based on recordings (of passenger cars, light and heavy goods vehicles) highlighted the important timbre parameters used by listeners in two conditions (signals recorded at the roadside and modified to simulate the effect of a standard facade). For noises heard inside dwellings, it seems that intensity and tonality are the most important factors (unlike car tires, truck tires can emit noise with a strong tonal character). In a second experiment, signals were synthesised to simulate tire passing noises, with controlled loudness and tonality. Participants were asked to evaluate the unpleasantness of sounds. Results showed that the contributions of both factors to unpleasantness were equivalent. This could lead to the recommendation that tonality be considered in of tire noise regulations.

Swelling effect on the microwave pyrolysis of waste car tires

AbstractSwelling can change the mechanical properties and structural characteristics of waste car tires (WCTs), so that the rubber molecular chain stretching, porousness becomes larger, which is conducive to improving the mass transfer effect and pyrolysis efficiency. Based on the modification characteristics of swelling, the swelling effects of different swelling agents, temperatures, tire types, and particle sizes were investigated. The results showed that coal tar can effectively swell WCTs, and the higher temperature and smaller particle size, contribute to better swelling. When the temperature is 40°C and the particle size is 1 × 1 cm, the equilibrium mass absorption rate of WCTs can reach up to 1.67 g/g, and the swelling effect is the best. In addition, combined with the unique microwave advantages, the swelling rate was further accelerated, WCTs reached swelling saturation 58.5 h earlier than in natural swelling. Moreover, the swelling effect on the three‐phase product output of microwave pyrolysis of WCTs was investigated. After swelling treatment, we achieved the deeper pyrolysis degree of WCTs and the yield of pyrolysis oil was relatively increased by about 39.2%, while the yield of both gases and solids decreased.

Hydraulic and physical property characterizations of materials for the design of sustainable urban drainage systems

In the context of extreme weather events, i.e., floods, and increased population in urban areas, traditional drainage systems fall short. The need to develop alternative runoff-control in urban environments and promote the circular economy has prompted us to study various draining materials, some of them recycled that might be used in SUDS construction and technosols. These include recycled shatter brick, gravel for draining concrete, recycled rubber from car tires, and substrates with different proportions of organic matter like compost, coconut fiber, peat, and manure. Mechanical parameters like porosity, density, and uniformity coefficients (among others) were calculated to assess hydraulic conductivity in the laboratory under saturated and laminar flow conditions. Alternative methodologies were applied to adapt the materials and samples to current standards procedures (UNE and ISO). The results, based on Darcy's law, show values equivalent to those of natural coarse soils, ranging from 4.4·10−5 to 1.1·10−1 cm·s−1.

The Extraordinary World of Sulphur Part 1

Abstract Sulphur is a highly reactive element, and is therefore able to enter into a great variety of chemical combinations, resulting in the formation of compounds of widely differing properties. Reactions involving sulphur, and the compounds which they produce, have stimulated and inspired people throughout the ages. Sulphur has always been associated with volcanoes, fires and smells. However, its story goes much further. Sulphur is present in thousands of products of the chemical industry, which are in everyday use. These include car batteries, car tyres, matches, paints, paper, textiles, food, detergents and pharmaceuticals. In part 1 of this essay, the evolution of the role of sulphur in the history of mankind is explained, through the eyes of etymology, geology, literature, art, and chemistry. In part 2 the role of sulphur in biochemistry and chemical technology is reviewed. In so doing, a case is established, to show that sulphur is the most extraordinary substance known to Man.

ПРОГНОЗИРОВАНИЕ НАГРУЗОЧНЫХ И ЖЕСТКОСТНЫХ ХАРАКТЕРИСТИК ПНЕВМАТИЧЕСКИХ ШИН МЕТОДАМИ КОМПЬЮТЕРНОГО МОДЕЛИРОВАНИЯ

Methods are considered for calculation of load and stiffness characteristics of pneumatic tires of radial and diagonal design, as well as modeling of flat and curvilinear motion of a car wheel with pneumatic tires. The calculated values of load characteristic and radial stiffness of 235/55R17 passenger tire and 46/90R57 all-steel truck tire obtained by finite element modeling in MSC.Marc software package are compared with the results of Biderman model calculation. In a quasi-static setting, the rolling process of the wheel with the 235/55R17 passenger car tire is analyzed in flat motion at a speed of 90 km/h and a rotational speed of 10.1–13.5 Hz. The following load and stiffness characteristics of the tire affecting smooth running, stability and controllability of the wheel are determined: dependence of the rolling radius on torque, circumferential stiffness, dependence of traction with the road surface on the amount of slip, coefficient of slip resistance, dependencies of lateral force and stabilizing torque on the angle of lateral skid.

Application of Various Brands of Silica Fillers in the Formulation of Treads of Car Tires

Application of Various Brands of Silica Fillers in the Formulation of Treads of Car Tires

Influence of tyre construction parameters on cavity noise amplification and its impact on electric vehicles

When the tyre rolls over a macro uneven road surface, it starts to vibrate which is responsible for cavity noise excitation. This excitation range typically lies between 180-250 Hz for passenger car tyres. With the rise of electric vehicles in the market, vehicle interior noise is becoming a key demand from OEMs across the globe. It is therefore paramount to understand how tyre parameters such as cavity, construction, compounds and reinforcements excite this cavity noise under tyre operating conditions such as inflation pressure, pre-load and vehicle speeds. External cavity noise reduction methods such as foam technology in tyres can help reduce this excitation. However, this also leads to other challenges such as increased product costs. This investigation therefore, shows possible solutions to minimize the impact of cavity noise amplification.

Current Performance of Floor Impact Sound Insulation in Wooden Apartment Buildings in Hokkaido

In Hokkaido, Japan, technological developments have been introduced to improve the floor impact sound insulation performance in wooden apartment buildings. However, such technological developments are not widely used, especially in rental properties. To effectively disseminate the required technology, it is vital to report examples of implementation. Therefore, we measured the performance of five types of wooden apartment buildings with high sound insulation performance and analyzed the results. The main results are listed below. (1) A relatively high performance was obtained by installing a floating floor and an independent ceiling. (2) For heavy weight floor impact sound insulation of a car tire source, a floating floor with a surface density of 60 kg/m2 or higher could achieve a performance of Li,Fmax,r,H(1)-60 or higher. However, in the case of a rubber ball source, vibration radiation noise from the wall surface of the lower floor is large, so it is necessary to consider vibration countermeasures. (3) For light weight floor impact sound insulation, sufficient performance cannot be obtained even with a floating floor. Therefore, carpet or wooden soundproof flooring should be used. (4) The light weight floor impact sound pressure level is high when the floor area of the sound receiving room is small.

Experimental investigation of road surface parameters affecting tire/road noise

It is known that tire/road noise is strongly affected by the properties of the road surface such as its profile and sound absorption coefficient. Several parameters, represented by mean profile depth (MPD), have been proposed or standardized as surface profile parameters, but none of them clearly explains the relationship with tire/road noise generation. This study attempted to identify a new surface parameter that correlates more closely with tire/road noise. Surface profile measurements and close proximity (CPX) measurements were conducted on several road surfaces with different properties on test tracks. Tire P1, the reference tire for the CPX method, and two types of passenger car tires were used for the CPX measurements. According to our experience, the variation of the peak height of the road surface with distance is closely related to the excitation input to the tires and thus noise generation. Therefore, we devised a road profile parameter to quantitatively evaluate the variation of peak height. A relatively strong correlation was observed between this parameter and the CPX level. The validity of this parameter will be verified by further measurements on general roads in the future.

Investigating Recycling Methods of End-of-Life Car Tires

In this research work, the amount of rubber dust formed as a result of the friction of the tires used on vehicles in a large city on the road was determined and it was shown that every day, approximately 5 grams of toxic rubber dust is swallowed by each of the city's population. This environmental disaster and its elimination ways of lifting have been investigated. Special compositions were prepared based on tires that were out of use and turned into waste. The optimal recipe was selected by using these compositions to prepare polymer asphalt concrete. tire recycling is of great economic importance. So, more than 80% of oil refinery products are used for their preparation, so by using them after use, we have solved both environmental and economic issues The study showed that if we add rubber scraps with 5 mass particles up to 1 mm to oil road bitumen, we can increase the main indicators of the obtained polymer bitumen composition by 2b time

Urbanization and Water Containers Influence the Mosquito Community with Consequences for Aedes aegypti.

We aimed to determine how the degree of urbanization in a Neotropical city influences Aedes aegypti (L.), a pantropical vector of urban yellow fever, dengue, Zika and Chikungunia, via other mosquito species, whether they are competitors or predators, native to the area or invasive. We conducted experiments twice a month during one year in the city of Kourou, French Guiana, on three sites characterized by increasing percentages of imperviousness (i.e., 0.65%, 33.80% and 86.60%). These sites were located in a ≈5ha forest fragment, a residential area with gardens, and in the older part of the city, respectively, and correspond to slightly, moderately and highly urbanized sites. There, we monitored twice a month during one year a total of 108 mosquito communities inhabiting four types of containers (i.e., a tank bromeliad, dry stumps of bamboo, ovitraps and car tires) installed in a random block design. In the tanks of the bromeliad, likely due to the acidity of the water, the immatures of native mosquito species prevailed, particularly Wyeomyia pertinans (Williston) in the slightly urbanized site. The general pattern was very similar in the three other types of containers where Limatus durhamii Théobald dominated in the slightly urbanized site, so that the abundance of Ae. aegypti immatures was low compared to those of native species. Yet, Ae. aegypti strongly dominated in the two more urbanized sites. These findings open up perspectives for vector management, including the conservation and/or the augmentation of natural enemies through modifications to landscape features.