ECONOMIC AND ECOLOGICAL ASPECTS OF THE USE OF NEW CRYOGENIC AVIATION FUELS

Until recently, the high rates of aircraft engine engineering’s development were ensured by the technological solutions improvement and the desire to approximate as much as possible the ideal thermodynamic cycle of turbojet engines. The traditional fuel for turbojet engines is an aviation kerosene – Jet-A fuel group and their regional analogies. The traditional way of aircraft engines efficiency increasing is a raising of a temperature in front of the high-pressure turbine. New alloys and technologies allow to increase the aircraft engines efficiency to a certain level. Raising the temperature in the combustion chamber by 50 degrees increases the efficiency, which leads to a 5% reduction in fuel consumption. However, this approach is technology limited and does not provide innovative solutions. The aircraft engine engineering’s development tempo in the 21st century continues to accelerate. The main driver of such processes in recent years is the tightening of economic and environmental requirements. Many aircraft manufacturers are actively looking for ways to reach a new qualitative level in terms of turbojet engines economic efficiency and meeting strict environmental requirements. The paper considers the feasibility of using new cryogenic fuels in aircraft turbojet engines, and possible ways for aircraft industry successful development.

A Grounded Theory on Sustainable Circular Public Procurement in Germany: Specific Product Case and Strategies

By using its purchasing power to procure environmentally friendly goods and services, the public sector can significantly contribute to sustainability in production and consumption. The sector’s support is also needed for the development of a circular economy (CE), but the absence of a suitable procurement practice often constitutes a barrier. A pressing example for a global need to develop the CE further exists in the tyre context. By the end of 2030, the number of end-of-life tyres (ELT) is expected to rise significantly. This article analyses the role and situation of public procurement and the necessity of quality infrastructure elements to support a sustainable tyre CE in the European Union’s member state Germany. It relies on a multiple case case study-based Grounded Theory approach and 22 interviews with public procurement professionals. Five types of barriers for sustainable circular tyre procurement were identified, concerning regulatory, technical, social, market, and ecological aspects. Possible strategies to overcome them were developed, leading to 14 recommendations for German policymakers and public procurement organisations. In particular, the recommendations focus on the two quality infrastructure elements ‘standards’ and ‘labelling’, with four standardization aspects and eight labelling topics in total.

Environmental management in the hotel and restaurant complex

In the current context, significant changes are taking place in the structure of Ukrainian industry. Powerful productions of some spheres of activity lose their urgency and, on the contrary, acquire the development of power of other branches, namely, craft productions, to the composition of which the company belongs. The result of the activity of the businesses complex is the formation of significant volumes of food waste (about 160 thousand ton), discharges of concentrated wastewater, wastewater discharges. The wastes of the restaurant industry have a wide nomenclature and a specific composition, under the conditions of their placement in the components of the environment form the ecological aspects of the negative effects. Food wastes of facility in this branch contain a significant amount of nutrients, organic substances and require complex processes of their processing. Meanwhile, according to their composition, production wastes can be involved in the transfer process with the removal of secondary raw materials and energy sources. Thus, there is a need to improve existing and new technologies for the transfer of hazardous waste in order to reduce the load on the environment. The results of the analysis of world and domestic developments in the field of technologies for the utilization of food waste allowed to determine the main methodological approaches to the transition. In the case of the utilization of food waste, biotechnological methods represent a significant interest. Thus, the work is devoted to the connection of the actual scientific-practical task, which consists in the scientific substantiation and improvement of the technology of the transfer of the population's needs.

Life form, diversity, and spatial distribution of macroalgae in Komodo National Park waters, East Nusa Tenggara

Komodo National Park is one of the favorite destinations for both domestic and international marine tourism. Marine tourism activities have caused environmental changes and impact on fisheries and marine resources. Macroalgae were also affected by the environmental changes, so management of macroalgae was required. Ecological data of macroalgae can be used as baseline data for coastal area management. The study aimed to determine the life form, species composition, spatial distribution, and ecological aspects of macroalgae assemblages in Komodo National Park waters. The study was conducted in September 2013, in eight locations, namely Setuga, Komodo Karang Makasar, Padar Kecil, Padar, Papagarang, Mangaitan, and Muntia island. Macroalgae samples were collected by the quadratic transect method. The data analyzed were Sorensen’s similarities. A total of 42 species of macroalgae were recorded, consisting of three Phylum: Chlorophyta (19 species), Ochrophyta (8 species), and Rhodophyta (15 species). Epilithic was the dominant life form of macroalgae. In general, macroalgae can be stably attached to hard substrates. The highest macroalgae diversity was found on Mangaitan Island (22 species). Halimeda and Amphiroa were macroalgae that can be found in almost all locations. Setuga Island had similar macroalgae with both Mangaitan and Muntia islands. The differences in the number of macroalgae species were influenced by environmental pressure, topography, and substrate profile. Management of macroalgae resources was needed to maintain the sustainability of the macroalgae ecosystem.

ECOLOGICAL ASPECTS OF MORPHOGENESIS OF CONNECTIVE TISSUE COMPONENTS OF THE PANCREAS OF A RACCOON DOG IN POSTNATAL ONTOGENESIS OF THE RADIATION FACTOR

There have been no studies devoted to the study of the pancreas of a raccoon dog living in a contaminated area in the world. Therefore, the aim of our research was to study the connective tissue components of the pancreas in a raccoon dog at different stages of postnatal ontogenesis. The material for the study was raccoon dogs seized from former settlements, in the vicinity of lakes Zhartai, Vyura, Gnezdnoye and the Nesvich River in the exclusion zone (30 – kilometer exclusion zone of the Chernobyl nuclear power plant). As a result of the studies, the features of the morphofunctional state of the pancreatic stroma under the influence of the radiation factor were revealed.

The Ecological Aspects of Urban Structure of Balige District Kabupaten Toba, Indonesia

Balige is the capital of Toba Samosir Regency. Balige District continues to develop dynamically, marked by the development and changes of the physical city structure Balige. It is about the real implications of a city’s physical growth and development that move dynamically, which can be seen from urban, suburban, and rural land-use patterns. The aim is to determine the ecological aspects of urban structures in the Balige District. The method used in selection is done through secondary data that does not directly provide data to researchers or analyzed documents and concluded. Initially, Balige City was centered on the pier up to Sisingamangaraja’s field, evidenced by water transportation still used today. However, the result of the study showed changes in the pattern of land use due to economic growth and social transformation.

Ecological Aspects of Urban Structure of The Pangururan District

Urban structure is a city-forming arrangement that has many meanings depending on the indicators used. Ecological approach as one of the indicators is defined as a study of the spatial and temporal relationships of humans which are influenced by forces, selective, distributive, and accommodative of the environment. Pangururan district located in Samosir Regency, North Sumatra Province, Indonesia is one of the areas that is becoming the main focus of tourism development in Indonesia. This has led to the development of the city. The research was conducted using qualitative methods with data collection methods through literature studies and aerial observations. This study aims to determine how the structure of the Pangururan District is analyzed using the ecological theory of urban structure.