closed cycle
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2021 ◽  
Vol 14 (4) ◽  
pp. 418-424
A. B. Dolgushin ◽  
A. A. Tsukanov ◽  
A. D. Petrov

The life of a modern person today cannot be imagined free from an urgent and urgent problem – the problem of waste recycling. At the same time, the environmental situation in large cities, including industrial enterprises, is mainly determined by the state of the waste treatment system. These include solid municipal waste, as experts call the garbage that is formed daily in everyday life and makes a long way from the garbage chute to the yard container and further to the city dump.At the moment, the infrastructure for collecting and processing secondary raw materials (glass, plastic, paper, batteries, etc.) is developing on the territory of many CIS countries, including Russia, while there are no reception points for textile waste of production and consumption in sufficient quantities, unlike in European countries. There are retail outlets that accept unnecessary textiles from the population, and in return provide discounts on their products. However, taking into account the volume of textile waste generation (about 4.2–4.8 million tons per year), the existing textile waste collection system, which collects only about 0.4% of textile waste, is clearly insufficient. Based on the identified problems, the authors of this article give a socio-ecological and economic assessment of the problem of handling textile waste of consumption in Russia. The analysis of the relationship of the problems of textile waste management to the UN Sustainable Development Goals is carried out. The international experience of applying the principles of the closed-cycle economy in relation to textile waste is considered and recommendations for the transition of the Russian textile industry to a closed-cycle economy are formed.

Neeraj Kumar Rajak ◽  
Neha Kondedan ◽  
Husna Jan ◽  
Muhammed Dilshah U ◽  
Navya S. D. ◽  

Abstract We present high resolution thermal expansion measurement data obtained with high relative sensitivity of ΔL/L = 10-9 and accuracy of ±2% using closed cycle refrigerators employing two different dilatometers. Experimental details of the set-up utilizing the multi-function probe integrated with the cold head of two kinds of closed cycle refrigerators, namely, pulse tube and Gifford-McMahon cryocoolers, has been described in detail. The design consists of decoupling the bottom sample puck and taking connections from the top of the multi-function probe to mitigate the vibrational noise arising from the cold heads, using which smooth and high quality thermal expansion data could be obtained. It was found that dilatometer #2 performs a better noise mitigation than dilatometer #1 due to the constrained movement of the spring in dilatometer #2. This was confirmed by finite element method simulations that were performed for understanding the spring movement in each dilatometer using which the effect of different forces/pressures and vibrations on the displacement of the spring was studied. Linear thermal expansion coefficient α obtained using both dilatometers was evaluated using derivative of a polynomial fit. The resultant α obtained using dilatometer #2 and either of the closed cycle cryostats on standard metals silver and aluminium showed excellent match with published values obtained using wet cryostats. Finally, thermal expansion measurements is reported on single crystals of two high temperature superconductors YBa2Cu3-xAlxO6+δ and Bi2Sr2CaCu2O8+x along the c-axis with very good match found with published data obtained earlier using wet liquid helium based cryostats.

А. Х. Аласханов

В работе приводятся возможности расширения сырьевой базы для получения качественных и прочных строительных композитов. Приводится понятие о ресурсном цикле, основанном на природном круговороте веществ (ПКВ) и обеспечивающем безотходный замкнутый цикл производства композитов. Обозначена актуальность и перспективность перехода на энерго- и ресурсосберегающие технологии безотходного производства. The paper presents the possibilities of expanding the raw material base to obtain high-quality and durable building composites. The concept of a resource cycle based on the natural cycle of substances (PCR) and providing a waste-free closed cycle for the production of composites is given. The relevance and prospects of the transition to energy- and resource-saving technologies of waste-free production are indicated.

PRX Quantum ◽  
2021 ◽  
Vol 2 (4) ◽  
Samarth Vadia ◽  
Johannes Scherzer ◽  
Holger Thierschmann ◽  
Clemens Schäfermeier ◽  
Claudio Dal Savio ◽  

2021 ◽  
Vol 6 (5) ◽  
pp. 437-444
K. A. Filiptsova ◽  
N. A. Orlyk ◽  
A. I. Bosenko

The purpose of the study was to investigate the peculiarities of changes in the general functional condition of the brain of highly qualified female athletes specializing in karate, in terms of omega potential indicators and to assess the adaptive capability of the central nervous system during physical load. Materials and methods. The study involved 14 highly qualified female athletes aged 17-22 years – representatives of the Odessa Regional Karate Federation. Determination of the dynamics of infraslow bioelectrical processes of the brain, namely omegapotential, was carried out according to the method of O. G. Sychov et al. (1980) at rest, after performing a test in one squat, with dosed physical load in a closed cycle (with reverse) and during the recovery period after exercise. Results and discussion. According to the results of anthropometric and physiometric measurements, the height of the studied girls specializing in karate, on average, was 164.43±0.86 cm, and body weight – 56.36±2.23 kg. The thorax circumference at rest was 84.86±1.57 cm, at the inhale – 89.57±1.49 cm, at the exhale – 82.5±1.57 cm. The average value of vital capacity of the lungs was 3457.14±101.93 ml, wrist dynamometry – 23.36±1.02 kg, back dynamometry – 63.57±3.53 kg. The analysis of the results of the study of infraslow brain processes showed that in the initial state the omega potential value ranged from 10 to 59 mV, which indicated the optimal baseline level in most female athletes before exercise. In the state of relative rest, the average omega potential values (21-40 mV) were found in 79% of the surveyed girls, high (41-60 mV) and low (up to 20 mV) – in 14% and 7%, respectively. The results of study of omega potential dynamics when tested in one squat indicate isolated cases of adequate responses and optimal activation of adaptive systems of the body to the functional load. In most female athletes, the violation of chemo-metabolic, neurohumoral and hormonal processes were observed after performing the test of one squat. The peculiarities of omega-potential dynamics, which were noted during the performance of dosed physical load in a closed cycle (with reverse), indicate a gradual decrease in the studied indicators relative to the initial state during the performance of bicycle ergometric load, especially during the period of reverse (heart rate = 150-155 beats / min) and at the end of testing. At the same time, the depth of shifts also increased, which reflects the significant tension on the central nervous system and other body systems of female athletes in response to physical load. After performing exercise at the 2nd and 5th minutes of rest, no recovery of infraslow bioelectrical processes to the initial level was recorded, which indicates the development of overstrain of adaptive mechanisms. Conclusion. Testing of qualified female athletes specializing in karate, using a functional test conducted in one squat, according to the data of average group indicators of omega potential revealed a violation of chemo-metabolic, neurohumoral and hormonal processes. The study of individual data shows that in most of the surveyed there are various violations of these body systems. The dynamics of infraslow bioelectrical processes in the brain of female athletes during testing using bicycle ergometric load in a closed cycle (with reverse) is characterized by a steady decrease in omega potential throughout the test, which reflects the overstrain of regulatory mechanisms and deep mobilization of functional capabilities. The restoration of the level of omega potential to the initial level at the 5th minute of the post-exercise period does not occur

Nour El Houda Chaher ◽  
Abdallah Nassour ◽  
Moktar Hamdi ◽  
Michael Nelles

AbstractNowadays, Tunisia faces challenging environmental and energy issues which relate mainly to the implementation of an appropriate solid waste management system capable of dealing with the high production of biowaste on the one hand, and the increased need for water and energy resources on the other. Therefore, the current study is intended to develop a closed cycle technical concept treating mainly food waste (FW) through combined biological processes. In this approach, FW anaerobic digestion (AD) was destined to provide a valuable input material for FW in vessel-composting by exploiting the produced digestates. To this end, the gathered AD-effluents of three systems (D1, D2, D3) were entirely analyzed to select, as a further step, the most suitable one to be subject of the suggested post-treatment. Hence, several physiochemical parameters were examined as key performance indicators. It mainly consisted of moisture content, pH, C:N ratio and heavy metals contents. The current findings depicted that the generated digestates were characterized by a high moisture content which inspired its utilization as an unconventional moisturizing agent (MA) aiming to reduce the fresh water consumption during the composting process. Thus, two experimental setups were carried out to evaluate the effect of the selected digestate on FW-in-vessel composting process performance, as a non-standard MA inserted to A2, comparing to the unamended one (A1) which was moistened by fresh water. In fact, basing on the above-mentioned criteria, the relatively high C:N ratio (of around 15), as well as the relatively significant rate of the required macro- and micro-nutrients promoted the exploitation of biochar-rich digestate (D3) as not only an efficient unconventional MA, but also as a composting process booster. Furthermore, the results revealed that the addition of D3 improved significantly the composting process performance in terms of steering parameters including the attained temperature, MC and pH. When it comes to the maturity and stability assessment, the decreased profiles of C:N ratio, the nitrification index (NI), as well as the respiration activity (AT4) ascertained the fulfilment of the required conditions for both A1 and A2 to produce stable and mature end-products. However, regarding the compost quality, the examined concentrations of heavy metals met the requirement set by German standards and attested that both A1 and A2 generated highly-qualified products, rated as class B and A, respectively. Furthermore, it is noteworthy to mention that even the AD-effluents which were classified as an “inappropriate substrate” to be inserted to the composters, met the required criteria to be applied directly to land as a highly-qualified liquid biofertilizer. This latter ascertained, additionally, the efficiency and feasibility of the suggested closed cycle for a sustainable FW management. Graphic Abstract

A. I. Sukhorukov ◽  
E. A. Zakharova

By methods of analysis and synthesis the article studies the problem of developing closed cycle economy in the field of hard communal waste treatment (HCW). Dynamics of waste making up was analyzed and its physical and mechanic properties and chemical composition were provided. The article gives economic tools, functions and classification of these tools that are necessary to organize the process approach to management. The authors put forward a promising scheme of treating HCW built on the basis of European experience and worked out the acute functional-structural scheme of the treatment system by the HCW complex, which demonstrates key business processes and tools of management. Such complex approach to describing the system of HCW treatment can simplify digital modeling of multi-variant business processes, such as burial of waste at waste-grounds, utilization at waste-burning plants, sorting and recycling at waste-recycling enterprises. Digital modeling with successful automated functional and cost analysis can give an opportunity to decrease uncertainty in the field of economic efficiency of managerial decision-making for rational HCW treatment and development of closed cycle economy in this sphere. A correct choice of approaches to the development of closed cycle economy in the field of HCW treatment can reduce the load on nature and support health of people.

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