CABI - CAB Abstracts

The process of laser welding of sheets of HSLA (high-strength low-alloy steel), DP600 (dual-phase steel) and TRIP steels was investigated. A weld was successfully made in a double-sided hot-dip galvanized sheet with a thickness of 0.78–0.81 mm using a laser power of 2 kW per pass without any pretreatment of the weld zone. Microstructure studies revealed the presence of martensitic and ferritic phases in the weld zone, which could be associated with a high rate of its cooling. This made it possible to obtain good strength of the weld, while maintaining sufficient ductility. A relationship between the microstructural features and mechanical properties of welds made in the investigated steels has been established. The highest hardness was found in the alloying region of steels due to the formation of martensite. The hardness test results showed a very narrow soft zone in the heat affected zone (HAZ) adjacent to the weld interface, which does not affect the tensile strength of the weld. The ultimate tensile strength of welds for HSLA steel was 340–450 MPa, for DP600 steel: 580–670 MPa, for TRIP steel: ~700 MPa, respectively, exceeding the strength of base steels.

The strong interdependency between economic growth and conventional energy consumption have led to significant environmental impact, especially with respect to greenhouse gas emissions. Conventional energy-intensive industries release increasing quantities every year, which has prompted global leaders to consider new approaches based on sustainable consumption. The main purpose of this research is to propose a new energy index that accounts for the complexity and interdependences between the research variables. The methodology is based on Principal Component Analysis (PCA) and combines the key components determined into a score that allows for both temporal and cross-country comparisons. All data analyses were performed using IBM SPSS Statistics 25™. The main findings show that most countries improved their economic performance since 2014, but the speed of the improvement varies a lot from one country to another. The final score determined reflects the complex changes taking place in each country and the efficiency of the governmental measures for sustainable economic growth based on low energy consumption and low environmental pollution.

Construction is a complex activity, characterized by high levels of capital investment, relatively long delivery durations, multitudinous risks and uncertainties, as well as requiring the integration of multiple skills delivering a huge volume of tasks and processes. All of these must be coordinated carefully if time, cost, and quality constraints are to be met. At the same time, construction is renowned for performing poorly regarding sustainability metrics. Construction activity generates high volumes of waste, requires vast amounts of resources and materials, while consuming a significant proportion of total energy generated. Digitalization of the construction workplace and construction activities has the potential of improving construction performance both in terms of business results as well as sustainability outcomes. This is because, to put it simply, reduced energy usage, for example, impacts economic and “green” performance, simultaneously. Firms tinkering with digitalization, however, do not always achieve the hoped-for outcomes. The challenge faced is that a digital transition of construction firms must be carried out at a strategic level—requiring a comprehensive change management protocol. What then does a digital strategy entail? This study puts forward an argument for the combined economic and sustainability dividends to be had from digitizing construction firm activities. It outlines the requirements for achieving digitalization. The elements of a comprehensive digitalization strategy are cataloged, while the various approaches to developing a digitalization strategy are discussed. This study offers practitioners a useful framework by which to consider their own firm-level efforts at digitalization transition.

Lead and zinc are heavy metals with toxic properties. These chemical elements are found in wastewater. The article deals with the removal of lead(II) and zinc(II) ions from polluted water using adsorption. As object of researches was selected natural polymer - fibber hemp (Cannabis sativa L.). Big quantities of fibber hemp are produced as waste in textile, agricultural industry, and therefore their usage could help to solve two problems - reducing quantity of fibber hemp as waste and reducing of water pollution by heavy metals. Pb(II) and Zn(II) ions adsorption with fibber hemp was investigated for contact time, pH, and heavy metal ions concentration impact. Pb(II) and Zn(II) ions biosorption rate was highest within the first hour, with optimal their biosorption recorded at pH = 5.0. Highest lead and zinc ions removal efficiency was recorded after 240-480 min and reached 60.5 and 61.7 % respectively. This study demonstrated the applicability and effectiveness of fibber hemp in lead and zinc ions removal, which could be applied for the sewage treatment plant in small scale.

The aim of this study is to reduce the phosphate concentration in treated wastewater using a small amount of the reactive filter media, Filtralite P. Biologically treated wastewater was passed through a filter with 215 g of Filtralite P. In the laboratory, the phosphate removal efficiency was 51% at a flow speed of 0.87 m/h. Under real conditions, in an experimental stand filled with 0.5 m3 of Filtralite P, the phosphate removal efficiency was 85% and the removal efficiency of total suspended solids was 57% after a 5-month period. The residual phosphate concentration in the filtrate from the experimental stand was 1 mg/L of PO4-P after the 5-month period. The experimental filtration plant was buried in the ground, and it did not freeze and worked well under winter conditions. The results of this study can be useful in the design and development of tertiary wastewater treatment plants in view of their sustainability potential.

In this study, coir fibers were successfully modified with henna (derived from the Lawsonia inermis plant) using a high-energy ball-milling process. In the next step, such developed filler was used as a reinforcing filler in the production of rigid polyurethane (PUR) foams. The impact of 1, 2, and 5 wt % of coir-fiber filler on structural and physico-mechanical properties was evaluated. Among all modified series of PUR composites, the greatest improvement in physico-mechanical performances was observed for PUR composites reinforced with 1 wt % of the coir-fiber filler. For example, on the addition of 1 wt % of coir-fiber filler, the compression strength was improved by 23%, while the flexural strength increased by 9%. Similar dependence was observed in the case of dynamic-mechanical properties — on the addition of 1 wt % of the filler, the value of glass transition temperature increased from 149 °C to 178 °C, while the value of storage modulus increased by ~80%. It was found that PUR composites reinforced with coir-fiber filler were characterized by better mechanical performances after the UV-aging.

Today, sustainability, sustainable development and clean environment come to the fore worldwide. Consequently, the concept of sustainability has been introduced in project management. Sustainability issues have gained particular attention in the real estate sector. However, despite the fact that this sector has a huge impact on the environment and society, real estate projects are most commonly chosen taking into account only their risk and return, and a very limited number of indices and methods are available to assess their sustainability. Moreover, all of the existing indices and models for assessing the sustainability of an investment project take into account only three dimensions of sustainability—environmental, social and economic. Therefore, the novelty of this work lies in constructing a real estate sustainability index (RESI) relying on an additional sustainability aspect—i.e., a technological dimension. The developed sustainability index could be useful in evaluating and comparing real estate projects. It would also promote technological progress and investments in new technologies within projects as sustainability is also considered in a new, technological dimension. A research study was carried out between September 2020 and December 2020. Following an analysis of the literature and different sustainability-related standards relevant for the real estate industry, sustainability criteria were chosen and then grouped into four (environmental, social, economic and technological) categories. The selection and ranking of the most relevant sustainability criteria were performed through a survey. The index was compiled by applying multi-criteria decision making methods.

The problems of developing online decision support systems concern the complexity of the transportation management processes, the multi‐dimensionality of data warehouses (DWs), and the multi‐criteria of decision making. Such issues arise in the management processes by supporting them with adaptable information and communication infrastructure for the management of the freight’s transportation processes. Our research domain involves the assurance of infrastructure for the provision of smart services for the operative management of multi‐modal transportation of freights under the conditions of the heterogeneity of communication channels and multi‐criteria decision support. The complexity of managing multi‐modal transportation processes raises some problems for ensuring the infrastructure for finding more optimal management solutions by the requirements of green development. This research aims to develop the approach for providing the infrastructure of intelligent smart services for adaptable implementation in management processes of online multi‐modal freight transportation. The objectives are forwarded to construct the multi-criteria decision‐making components and integrate them into the multi‐layered, computer‐based information management of intelligent systems. We present the steps of extension of the structure of the knowledge‐based system with a multi‐criteria decision support method, and the possibilities to work under the conditions of wireless networks and the recognition of context‐aware situations The results are demonstrated for the analysis of alternatives by assessing the multi‐modal transportation corridors between the East and West regions of Europe, and the opportunities to evaluate them for more effective managerial perspectives under sustainable development requirements.

A new adhesive material and a restoration technology for marine equipment units are proposed. The optimal content of hardeners of different nature is found, and the effect of temperature conditions used for crosslinking epoxy resin DER-331, on the adhesive properties of the polymeric material is determined. The polymerization of the epoxy oligomer DER-331 and polyethylene polyamine (PEPA) hardener at a temperature T = 413 ± 2 K is found to enhance the adhesive properties of the polymeric material by 3.2–3.6 times, as compared to polymer GEN-150. In addition, the separation pattern of metal surfaces was analyzed, which allowed for an in-depth evaluation of the adhesive strength at separation and its variation upon increasing the content of hardeners introduced. Based on complex studies, it is shown that the developed polymeric adhesive should be used in the restoration of marine transport units, in particular, wheel fit in the compressor section of turbocharger.

The paper analyzes the main issues of power market development for clean energy production within the broader framework of ensuring the country’s energy security. In addition, special attention is paid to the technologies aimed at reducing emissions of toxic substances and greenhouse gases by the fossil-fired power plants. Even though the future electricity markets would most likely depend on the high shares of renewable energy sources (RES) in the electricity system, energy efficiency such as the one based on the near-zero emission technologies might also play a crucial role in the transition to the carbon-free energy future. In particular, there are the oxy-fuel combustion technologies that might help to reduce the proportion of unburned fuel and increase the efficiency of the power plant while reducing the emissions of flue gases. Our paper focuses on the role and the place of the near-zero emission technologies in the production of clean energy. We applied economic and mathematical models for assessing the prospects for applying oxy-fuel combustion technology in thermal power plants, taking into account the system of emission quotas and changes in the fuel cost. Our results demonstrate that at the current fuel prices, it is advisable to use economical combined cycle gas turbines (CCGT). At the same time, when quotas for greenhouse gas emissions are introduced and fuel costs increase by 1.3 times, it becomes economically feasible to use the oxy-fuel combustion technology which possesses significant economic advantages over CCGT with respect to the capture and storage of greenhouse gases.