bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of the responsiveness of new potato hybrids to various doses of mineral fertilizers
Authors: Tulinov A G , Lobanov A Y
Published: June 2022

Potato is an agricultural crop with a high removal of mineral nutrition elements and is responsive to fertilizers. Therefore, it is necessary to provide a system of mineral fertilizers for it, which contributes to obtaining a high yield with good indicators of the quality of tubers and meeting the standards of sanitary and hygienic control for the content of nitrates in tubers. Studies of new potato hybrids for responsiveness to mineral fertilizers were carried out on experimental fields of the Institute of Agrobiotechnologies FRC Komi Science Center Ural Branch of the Russian Academy of Sciences (Russia, Republic of Komi, Syktyvkar). The object of the study is three mid-season hybrids that passed the competitive test based on the results of a four-year selection selection (2018-2021): 1992-14 (Udacha × Elmundo), 2000-60 (Colette × FZ 1867), 2139-5 (Courage × Aurora ). Hybrids were obtained from FRC Potato named after. A. G. Lorkha (Russia, Moscow region, township Korenevo). The zoned mid-early variety Nevsky was used as a standard. The study was carried out according to the following scheme: control - without fertilizers, dose 1 - N100P80K150, dose 2 - N150P120K225 and dose 3 - N200P160K300. As a result of studying the effect of mineral fertilizers in the cultivation of new promising potato hybrids, the highest complex efficiency of nitrogen, phosphorus and potassium doses in the combination of N100P80K150 was established. The use of this dose of fertilizers made it possible to obtain a significant increase in yield by 20-25% for the studied hybrids and standards, while the fractional composition of tubers changed in favor of the medium and large fractions, the content of dry matter, starch and vitamin C was maintained at the level of the variant without the use of fertilizers, while In this case, there was no excessive accumulation of nitrates in potato tubers.
The use of resource-saving technologies in crop production
Authors: Amirova E F , Aygumov T G , Kosnikov S N , Suchkov D K
Published: June 2022

Crop production is one of the most important branches of agricultural production, which ensures food security and independence of the state. The primary task of farmers is to supply the population with high-quality agricultural products. Agricultural production is associated with many factors, some of which have a negative impact on its development. The transition to energy and resource-saving technologies is an essential condition for the further development and functioning of the agricultural sector. The introduction of resource-saving technologies will ensure the preservation and restoration of soil fertility and the environment, the rational use of production resources and the full realization of the agricultural potential.
Genetic control of parameters of harvest structure elements in the corn diallel complex
Authors: Zaytsev S A , Guseva S A , Volkov D P , Nosko O S , Erohyna A V
Published: June 2022

The article discusses the results of the use of diallel analysis in the study of self-pollinated maize lines. The average values of the elements of the structure of the grain yield in self-pollinated lines, as well as the average group indicators of hybrids, are noted. The effects of the general and dispersion of the specific combinative ability of lines are revealed. The ranking of the average group values of hybrids by the weight of the cob was carried out, which made it possible to arrange the lines in the following sequence: CL 7 < X 46 < SE 19 < Od 28 < KS 25 < LV 32 < Bg 1266 < Om 255 < Uk12 D 2 < RSK 25 < Om 232 < Mk 130 U < RSK 3 s< RSK 7 < RN 26 < Mk 11. In 2016-2019 A significant influence on the manifestation of the weight of the cob, the weight of the grain from the cob, the yield of grain, the number of grains in a row and the grains on the cob of the paratypical component of the dispersion (E) was noted.
Scientific and technical basis for the implementation of combined technologies using solar and wind energy in the conditions of Turkmenistan
Authors: Saryyev Kakageldi , Nazarov Serdar , Matyakubov Amirhan
Published: June 2022

The article discusses issues related to uninterrupted power supply to settlements that are not connected to the central power supply system. The use of combined systems of photovoltaic solar and wind power plants in the conditions of Turkmenistan is explained in details and the importance of designing combined systems for power generation is proved. A software method is also proposed for the reliable execution of design and calculation works of combined plants in a short time. An analysis is given of the possibility of accumulating excess electricity generated during the day in accumulator batteries. The reasons for the need to use a combined system of photovoltaic solar and wind power plants are being carefully studied.
The mechanism of balanced development of the agro-industrial complex in the regional aspect
Authors: Dvoryadkina E B , Ermakova A M , Kustysheva I N , Kryakhtunov A V
Published: June 2022

The article examines the current level of the agro-industrial complex of the South of the Tyumen region. The main problems hindering the development of the industry are identified. Prospects and mechanisms of influence on the balanced development of the agro-industrial complex are revealed. The authors describe and give arguments for the positive impact of the balanced development of the agro-industrial complex on the economic component of the region.
Renewable and alternative energy sources. Green energy
Authors: Beksultanova A I , Dzhankhotova P M , Shardan S K
Published: June 2022

Environmental degradation and depletion of natural resources make us think about how we can get electricity and heat from renewable sources. This article discusses the theoretical foundations and characteristics of RES, analyzes foreign experience and Russian achievements in the organization and development of RES. The analysis showed that on a global scale, the key to energy policy is the transition from environmentally friendly fuels to clean renewable energy sources. Renewable energy sources account for more than a quarter (26%) of global electricity production. Over the past 20 years, the world’s electricity production based on renewable energy has increased more than 10 times, solar and wind energy are developing. Thanks to comprehensive policy measures, investments in research and development in the field of alternative energy in Europe, the USA, etc., renewable energy technology has become widespread. Thanks to technological advances in this area, these countries are currently facing a reduction in the cost of electricity generated using renewable energy sources. Despite the world experience, the obvious advantages of renewable energy sources (inexhaustibility of energy resources, environmental friendliness, lack of a fuel component in the cost of energy produced) and their huge potential in Russia, the development of unconventional energy has not been adequately developed. The share of RES in electricity production in the country is 0.2%
Solutions for the rational use of water in the conditions of the Republic of Uzbekistan
Authors: Kurbanbaev Sagit , Turlibaev Zakir , Urazimbetova Yulduz
Published: June 2022

The article studies data on the use of water in the territory under consideration and, on their basis, suggests ways of their rational use. Recommendations are given for the rational use of water, these are mainly measures to increase the efficiency of the on-farm network, improve the technique and technology of furrow irrigation, and introduce advanced systems of equipment and technology for irrigation.
Ecological monitoring of soils in urban and rural areas
Authors: Shvets N I , Sidorova K A , Yurina T A , Matveeva A A
Published: June 2022

The burden on the environment is increasing in direct proportion to the development of the scientific and technological revolution of mankind. Large industrial centers are characterized by the release of a diverse complex of pollutants into the environment, including HMs, which are deposited on the earth’s surface, polluting plants and soil. The article presents the results of determining the level of heavy metals in the soils of urban and rural areas. According to the data obtained, in the soils of household plots in the territories of rural settlements, a significant decrease in heavy metals to the MPC level was revealed in comparison with the same pollutants in urban household plots. When conducting a correlation analysis, a relationship was established between the value of the mobile form of the element in the soil and the gross forms of the studied HMs, however, the mobility of the elements in the soil is more variable in comparison with the indicators of urban areas.
Study of varieties of meadow clover by economically valuable characteristics
Authors: Kelekhsashvili L M , Lekova I A
Published: June 2022

The article evaluates the source material of clover according to a complex of economically valuable features. Perennial varieties of meadow clover with high winter hardiness, fodder and seed productivity, tolerance to major diseases have been studied. It was revealed that all the studied varieties are adapted to the conditions of the foothill zone of North Ossetia.
A chance to “cure” local climate systems and reconcile humanity with Nature
Authors: Kolokolov Yu , Monovskaya A
Published: June 2022

Sustainable development becomes illusive when the observed reality demonstrates extraordinary oscillations beyond habitual seasonal patterns. Sound estimations on climate destabilizations and their negative consequences as well as attempts to return to desirable seasons remain endless disputable until the uncertainties and oddities of local climate dynamics remain unclear. Per se, the clarification requires a physical meaning of the so-called interannual variability. At the same time, valid evidence to such point can be achieved only if there is a dynamical system describing local climate dynamics in both weather and climate terms simultaneously. Nothing success to satisfy this requirement existed before the rule of modes was discovered in 2014 (Kolokolov & Monovskaya) by the processing of temperature observations under the hypothesis that a local climate system represents a solar energy converter obeyed the astronomic-based hysteresis control with double synchronization. After, this hypothesis was verified completely and developed into the regulatory theory of local climate dynamics to analyze nonlinear stationary and nonstationary processes taking into account regularities of bifurcation scenarios and regulatory responses. The paper focuses on the aspects of this theory connecting with seasonal evolution rapidly and individually developing in local climate due to anthropogenic destruction of ecosystem equilibrium. In other words, Nature is the Great Dictator demanding from men to obey undeviatingly physical laws, among which “controlled chaos” and “democratic reforms” are absent. In practical application, it means that local climate systems need urgently careful cure to slow down global ecosystem collapse and to get a chance to reconcile humanity with Nature. The paper seems to be interesting to responsible researchers and practitioners oriented to efficient work to hold back from the destructive-for-human-activities transition towards a novel global climate.
Dynamics of population change, pollinators biodiversity and their role in managing the sustainability of biocenosis
Authors: Mishin I N
Published: June 2022

The article presents the results of long-term observations and a comparative analysis of changes in the biodiversity of insect pollinators and entomophilic plants of two closely spaced biocenoses (Test plots 1 and 2). In the initial period of observation, both sites had a comparable ecological state and relatively high biodiversity of pollinators and plants, Apidae (55%) prevailed in Test plot 2, and Diptera dominated in Test plot 1 (32.7%). The number of pollinators was approximately 44% higher in Test plot 2 than in Test plot 1. The number of pollinators, their species diversity and plants decreased fivefold in the biocenosis of Test plot 1 in the second observation period (after 15 years), signs of degradation of the phytocenosis of the Test plot 1 were observed. Woody vegetation and cereals predominated in the phytocenosis. The number of pollinators and their species diversity increased (approximately 2 times) in the biocenosis of Test plot 2, Apidae dominated in this area (about 32%). High number of legumes in the herbage and the intensive pollination activity of bees and other pollinators were undoubtedly one of the factors for a stable state of the biocenosis of Test plot 2. The article indicates that the controlled anthropogenic impact on biocenoses, in particular the creation of a dense grassy cover based on hybrid clover, the creation of nesting spots for bumblebees and single bees, the development of beekeeping will allow for targeted impact on biocenoses to create their stable state with a high level of biodiversity and productivity.
Features of the structure and formation of oil deposits in the sediments of the Bashkirian stage of small oil fields on the western slope of the South Tatar arch
Authors: Korolev E A , Morozov V P , Eskin A A , Gazeeva F M , Kalimulina A R
Published: June 2022

Oil-bearing carbonate complexes of the Bashkirian stage of low-amplitude brachianticlinal structures on the western slope of the South Tatar arch are considered. It has been established that the prospects for oil production are associated with the upper parts of the sections, where layers of algal-foraminiferal limestones - packstone occur, overlain by dense clayed mudstone-wackestone limestones. Oil deposits of the dome type, hydrodynamically isolated, are under the pressure of regional or bottom waters. Cap rocks, reservoir rock, water-oil contacts are clearly distinguished in the structure of deposits. The formation of the main elements of oil fields occurred at the stage of sedimentation due to eustatic fluctuations in the level of the epicontinental sea basin. At the stage of transgression, the formation of future reservoir rocks took place, at the stages of regression - cap rocks. The reservoir rocks acquired high capacitive-filtration properties during the period of migration of water-oil fluids. At this time, the dissolution of micritic calcite cement took place, the removal of the dissolved substance outside the reservoir bed, the filling of the void space with oil, and the displacement of residual water to the wings of uplifts. The next stage of transformation of reservoir rocks is associated with the processes of natural waterflooding of oil deposits. The penetration of regional pressure water into the oil reservoir contributed to the formation of local zones of water-oil contacts. Due to the oxidation of hydrocarbons inside the oil deposits in the OWC zone, bituminous and water-bearing subzones were formed. In the first one, intensive leaching of calcite occurred with the simultaneous formation of patchy-banded segregations of calcitized rocks, healing of cavern cavities with diagenetic dolomite and anhydrite. In the second subzone, the process of dissolution of bituminous films on the walls of caverns was going on, accompanied by secondary cementation of pre-existing cavities with diagenetic calcite and chalcedony, which determined the light color of reservoir rocks.
Stages of cross-border integration of border specially protected natural areas at the junctions of the state borders of the three countries in various parts of the planet
Authors: Novikov A N , Biksaleev A A
Published: June 2022

Cross-border environmental interaction of neighboring countries implies the coordinated functioning of their border “green” frames, which unite specially protected natural areas of various types. The methodological basis of the study is the following scientific concepts: territorial economic structures of Academician of the Russian Academy of Sciences P.Ya. Baklanova; polarized biosphere B.B. Rodoman; ring structures V.L. Martynov; trinitarian geography A.N. Novikov. The process of integrating “green” frameworks takes place in four stages and will end with the territorial organization of cross-border radial-circular structures. On planet Earth, at the junctions of the borders of the three countries, there is a process of formation of specially protected natural areas (SPNA), which become border contact links of the Central Active Zones (CAZ) of the I.C.-B.T.-L.R. These CACs extend their influence deep into the territories of each of the three countries, involving nearby protected areas in their sphere of influence and turning them into Radial Active Zones (RAZs). RAZ, closing on the periphery through the Edge Active Zones (EAZ), form radial-annular structures. The process of transboundary radial-ring integration goes through four stages: external environmental separation; stage of outwardly isolated growth; transboundary environmental and tourist contact; the stage of mutually coordinated territorial organization of border sectors into trans-border radial-ring “green” (environmental) frameworks in the I.C.-B.T.-L.R. format. The environmentally-centric I.C.-B.T.-L.R. that Russia and its neighbors are forming are at various stages of development. In modern conditions, for the formation of cross-border environmental policy, it is extremely important to take into account the existing international experience of consistent environmental integration of countries in the form of the formation of transboundary radial-ring “green” (environmental) frameworks.
Determination of the permissible duration of downtime electric power processes in agricultural production
Authors: Bakirov S M , Logacheva O V , Ivankina Y V , Loshkarev I Y , Shlyupikov S V
Published: June 2022

The article describes the impact of electric power processes in agriculture. The paper defines the value of the sensitivity of the agricultural process, which was defined as the ratio of productivity to the duration of the stop of the electrified process due to the failure of electrical equipment. The results of the research are demonstrated on the example of agricultural buildings in which various production processes take place, and graphical dependences of productivity on the duration of downtime of electric power equipment are also presented in the paper.
Producing marketable products by low-tempertature thermolysis of municipal solid waste
Authors: Sevostyanov V S , Shein N T , Sevostyanov M V , Shamgulov R Yu , Obolonsky V V
Published: June 2022

This article provides a method for recycling municipal solid waste (MSW) and industrial waste by low-temperature thermolysis. The proposed technology and technical devices make it possible to solve a range of scientific, technical, research, design, technological and environmental problems. The solutions take into account the conditions of existing production facilities and are aimed at eliminating the existing technical and technological constraints in resource-saving and energy-saving areas.
Thrust estimation for HTS-magnet based Magneto Plasma Dynamic Thrusters (MPDT)
Authors: Kumar Meena Lokesh , Anand A , Gour A S
Published: June 2022

At present time, electric propulsion is being considered for outer deep space missions. Magneto Plasma Dynamic Thrusters are capable of accelerating semi- neutral plasma gas (Xenon, Iodine, Argon, Ammonia, or Lithium) to a high exhaust velocity using combination of RF power & high magnetic fields. High Temperature Superconducting (HTS) coils can generate high magnetic field due to high operating current density at temperatures below its critical temperature(Tc). These superconducting coils can be cooled by using the cold of outer dark space. The use of 2nd Generation (2G) HTS coils can increase thrust, by increasing high magnetic field with very low power consumption. Thus, specific impulse due to the combination of RF plasma and HTS based superconducting high magnetic field is increased drastically. In this paper, the thrust calculation are carried out for MPDT for varying magnetic fields produced by superconducting coils. The estimation of exhaust velocity and thrust generated by plasma for an MPDT is of great challenge and is required to determine for calculating the life of mission as well as the distance of travel. These estimations are required to support the indigenous development of MPDT.
Experimental study on a helium-4 sorption cryocooler
Authors: Xi Xiaotong , Yang Biao , Gao Zhaozhao , Chen Liubiao , Zhou Yuan , Wang Junjie
Published: June 2022

The sorption cooler is one of the commonly used Sub-Kelvin temperature refrigeration technologies, used in space exploration and ground experiments to provide a low temperature below 1 K. In this paper, a sorption cooler using helium-4 as the working gas has been developed. At a heat sink temperature of 3 K, the lowest no-load temperature of the developed sorption cooler is 843 mK and the hold time below 1 K is 4 hours. The effects of different sorption pump temperatures and sorption pump cooling rates on the refrigeration performance were studied through experiments. The test results show that during the condensation process, when the temperature of the sorption pump is higher than 45 K, the pump temperature has little effect on the liquefaction efficiency, and speeding up the cooling rate of the sorption pump is conducive to obtaining a lower refrigeration temperature.
Investigation on the dynamic adsorption characteristics of activated carbon to Helium-4 for 4-20 K regenerator of cryocoolers
Authors: Yang Biao , Xi Xiaotong , Gao Zhaozhao , Chen Liubiao , Wang Junjie
Published: June 2022

With the advantages of long life and high reliability, cryocoolers gradually substitute cryogenic liquids to become a critical guarantee for the stable operation in space exploration. For cryocoolers, the regenerator is a key component that strongly influences its refrigeration performance. The specific heat of current commonly-used regenerator materials below 20 K is significantly lower than that of the working gas Helium-4, resulting in insufficient cold storage capacity of the regenerator and further limiting the cryocooler’s ability to obtain lower temperatures and larger cooling capacity. In this paper, activated carbon is used to absorb a part of helium in the regenerator to replace the traditional magnetic regenerator materials. By establishing a low-temperature dynamic adsorption model, the dynamic adsorption characteristics of activated carbon to Helium-4 in the temperature range of 4-20 K were studied, and the effect of its microscopic adsorption/desorption heat effect on the performance of the regenerator was investigated.
Development of Adiabatic Demagnetization Refrigerator for Future Astronomy Missions
Authors: Jin H. , Shen J. , Li C. Z. , Wang C. , Yu F. Q. , Zu H. Y. , Liu P. , Ding J. , Li K. , Wang Y. N. , Dai W. , Zhou Y. , Cui W.
Published: June 2022

The superconducting microcalorimeter provides astronomers with a new tool to probe the hot universe. This kind of detectors has superb energy resolution and high detection efficiency, which is important for diffuse X-ray detection. Astronomy missions, such as the Hot Universe Baryon Surveyor (HUBS) and Diffuse X-ray explorer (DIXE) proposed in China, is going to employ superconducting microcalorimeters. The superconducting microcalorimeter works in its superconducting transition region, which is at a very low temperature(<100 mK). Realization of such a low temperature in space is challenging. Adiabatic demagnetization refrigerator (ADR) is a good candidate for milli-Kelvin cooling system. Here we introduce our recent work on ADR design and construction. Most of the key components for building an ADR have been designed and fabricated. Recently we integrated all components and built a two stage ADR. Preliminary performance on each stages test has been conducted separately. In its performance test, starting from 4 K, the FAA stage could cool down to 156.7 mK and the GGG stage could reach 768.4 mK. This result shows promise for future development.
Design and analysis of 5 kW helium turbine for EAST cryoplant
Authors: Chen S X , Zhang Q Y , Fu B , Li S S , Fan C F , Zhang C J , Zong Y W
Published: June 2022

The helium turbine is an important core component in the refrigerator, which provides support and guarantee for the stable operation of the cryogenic system. This paper refers to the parameters of one of the four helium turbines in EAST, designs a 5 kW helium turbine. The overall structure of the turbine has been described, and the design and analysis of the impeller and bearing have been carried out. Through CFD analysis, the internal pressure and temperature change law of the flow is analyzed. The variable-condition operating characteristics of the turbine are predicted, and it is found that the turbine can maintain efficient operation within a wide range of mass flow changes. The bearing performance is calculated by solving the Reynolds equation. After determining the optimal bearing clearance 28 μm based on the principle of maximum stiffness, bearing performance parameters of load capacity and stiffness can be further calculated.
Experimental research on performance of an oil-free moving-coil symmetrical dual-piston linear compressor for the J - T throttle refrigerator
Authors: Liu Y L , Sun J , Xun Y Q , Chen H L , Huang Z J , Cai J H , Hong G T
Published: June 2022

In order to improve the efficiency of the Joule-Thomson (J-T) throttling refrigerator, an oil-free symmetrical dual-piston moving-coil linear compressor was developed, and its principle was demonstrated in detail. As the core component of the J-T throttling refrigerator, the linear compressor provides the pressure ratio and mass flow rate required by the throttling cycle. The linear compressor prototype was tested with nitrogen to evaluate its performance at different pressure ratios, strokes, and driving frequencies. Key performance parameters have been obtained, and the experimental results show that the input power is 175.2 W, the mass flow is 1.128 g/s, the unit power mass flow is 6.438 mg/s/W, the motor efficiency, volumetric efficiency, isentropic efficiency, and isothermal efficiency is 87.7%, 81.5%, 74.9%, and 63.7% at the design parameter (pressure ratio of 3.0, stroke of 10.0 mm, frequency of 60.0 Hz), respectively. The maximum mass flow rate is 1.742 g/s, and the maximum motor efficiency, volumetric efficiency, isentropic efficiency, and isothermal efficiency is 88.1%, 94.0%, 81.2%, and 73.4%, respectively. The symmetrical dual-piston linear compressor brings large-capacity and high efficiency, which provide a useful attempt and reference for the optimization of the linear compressors for the J-T throttling refrigerator.
Mathematic prediction and experimental research of gas thrust bearing for high-speed turbo-expander involving hydrogen, helium, nitrogen and air working fluids
Authors: Yan H , Zhang X H , Peng N , Zheng L W , Ke C L , Li K R , Liang Y W , Xiong L Y , Dong B , Li J , Liu I Q
Published: June 2022

High-speed turbo-expander is the key component of large-scale cryogenic liquefaction system and the gas thrust bearing is widely applied in turbo-expander due to the introducing exceptionally low contamination to the gas flow and low viscosity. However, the load capacity of gas bearing is low and it is often difficult to obtain the load capacity because of nonlinear problem. The paper establishes a mathematic prediction model to obtain the load capacity of gas thrust bearing directly and quickly. The model is universal for hydrogen, helium, nitrogen and air working fluids. A new dimensionless variable (Φ
t) is proposed and the function between the Φ
t and load capacity is found. Meanwhile, an experimental study is carried out to validate the mathematic prediction model. The results from the prediction model show good agreement with the experimental data. Based on the model, the load capacity for various working fluids is the same as long as the Φ
t is the same, which can be used to conduct experimental research on the replacement of potentially flammable such as hydrogen by inert gas.
A preliminary study of 4He convective heat switches
Authors: Yu F Q , Shen J , Zou A H , Li K , Wang C , Dai W
Published: June 2022

Heat switches are key components in sub-kelvin refrigeration. It is widely used in cryogenic systems, such as controlling thermodynamic cycle, coupling/decoupling redundant cryocoolers, accelerating the cooling of cryogenic components and so on. Convective heat switch features simple structure, no moving parts and great thermal conductance, which is mainly used to precool cryogenic components. In order to accelerate the pre-cooling of a test platform to 4K, the passive convective heat switch is investigated in this paper, which consists of a circuit comprising two identical stainless steel tubes and two copper cavities respectively connected to the cold and warm stages. The ON/OFF state of the switch is realized by the presence/absence of a gravity-driven convective helium-4 gas loop. Several convective heat switches with different cavity structures and charge pressures are designed and assembled. The preliminary experimental results on thermal conductance are presented. With a typical dimension of a cylindrical cavity with a diameter of 28mm and a height of 16.8mm, a stainless steel tube with a diameter of 9.6mm and a length of 72mm, thermal conductance of 40-50mW/K in ON state has been obtained.
Analysis of oxygen liquefaction with transient flow rates for ISRU systems
Authors: Grotenrath R. , Kashani A. , Hauser D. , Johnson W.L.
Published: June 2022

Human occupation of lunar and Martian surfaces requires in-situ resource utilization (ISRU) to create a sustainable environment with the limited resources available in space. Fuel and oxidizer generation is essential for developing a refuelling capability for spacecraft, significantly reducing the propellant mass required for landing. Liquefaction systems are a key step in producing and storing cryogenic liquids such as oxygen, hydrogen, and methane. All those fluids are critical to propulsion, life support, and other spacecraft systems. NASA has previously confirmed the presence of water on the Moon and an electrolysis process can be used to separate the oxygen from the hydrogen molecules. Oxygen has also been found within lunar regolith and can be separated through ISRU processes. The extracted oxygen gas can then be liquefied inside a storage tank with tube-on-tank heat exchangers for future use as an oxidizer for propellants. While steady state liquefaction performance is easy to model, power limitations and cyclical environments caused by the change in Sun exposure between day and night periods potentially call for transient operations. The following analysis was performed using the Thermal Desktop software to investigate how various transient gaseous oxygen (GOX) flow rates impact the production and storage of liquid oxygen (LOX) in a 1-g liquefaction system. Variations of sinusoidal and exponential step functions were selected to model potential GOX flow rates that could be experienced by ISRU systems on lunar or Martian surfaces. This early computational analysis provides some insight on how transient operations impact oxygen liquefaction systems and helps illustrate operational questions to explore experimentally throughout the design process.
Preliminary design of a helium cryogenic system for SAND detector at LBNF-DUNE near site
Authors: Wang L , Montanari D , Creus-Prats J , Lawrence A , Cline G , Delaney M , Adamowski M , Leitner M , Matichard F
Published: June 2022

The Long-Baseline Neutrino Facility (LBNF) is providing a helium cryogenic system to support the superconducting solenoid magnet of the System for on-Axis Neutrino Detection (SAND) for the Deep Underground Neutrino Experiment (DUNE) Near Site at Fermilab in Batavia, IL. The design started in 2020 and construction is set to begin in the mid 2020‘s.The helium cryogenic system primarily consists of a helium refrigerator system, distribution valve boxes, vacuum-jacketed helium and nitrogen transfer lines, warm gaseous helium transfer system, instruments and control system, and gaseous helium storage tanks. It is designed to provide supercritical helium at around 3 bara and 5 K with expansion from 3 to 1.2 bara in the SAND cryostat and 70K forced cold gas helium to cool the thermal shields of the SAND cryostat. The SAND superconductive magnet is indirectly cooled through a liquid helium thermosiphon cycle. A pair of 3 kA leads is cooled by the gas helium vaporized from the liquid helium reservoir in the cryostat turret. The helium system will share the liquid nitrogen tank and liquid nitrogen phase separator with the Near Site Liquid Argon system. The helium recycle compressor system, GHe tanks and LN2 tank will be located on the Surface. The cryogenic facilities including refrigerator cold box, valve boxes and LN2 phase separator will be located on the shaft cryo-mezzanine in the underground cavern. The shaft connecting surface and cavern is more than 60 meter deep. The helium vacuum-jacketed transfer line between the cold box and the SAND magnet is more than 50 meter long. This paper presents the preliminary design of the helium cryogenic system including the design scheme, process flow diagram, heat load estimates, layout plan and so on.
CFD Modelling of a Helium Cryogenic Pulsating Heat Pipe
Authors: Xu C , Pfotenhuaer J , Miller F
Published: June 2022

This paper explores the development of a 3D model using ANSYS Fluent to characterize the two-phase (gas/liquid) flow of helium in a cryogenic pulsating heat pipe. The model includes condensation and evaporation phenomena and uses the VOF model to capture aspects of the two phase flow. Temperature dependent properties were applied for helium in the range of 2.2 K and 20 K. Bubble formation and movement were observed, as well as flow direction at various times in each of the individual pipes. Grid independence tests were performed by plotting the average temperature of different sections. The influence of the number of turns on the performance of PHP is also investigated.
Development of a volatile organic compounds cryogenic condensation recovery system cooled by liquid nitrogen
Authors: Xu Hao , Xi Xiaotong , Xu Xiafan , Guo Jia , Chen Liubiao , Ji Wei , Wang Junjie
Published: June 2022

Volatile organic compounds (VOCs) are important precursors of ozone and PM2.5, and the reduction of VOCs emission is a key to control ozone and PM2.5 pollutions. For high-value VOCs such as oil gas, the cryogenic condensation method based on liquid nitrogen cooling is an effective way to recover VOCs. This method can achieve a refrigeration temperature of -170°C or even lower so that the treated exhaust gas concentration can satisfy the emission standard. In this paper, a thermodynamic model is established to calculate and analyze a designed three-stage condensation recovery VOCs system process based on liquid nitrogen cooling. A set of experimental equipment was further developed and tested. And the system process, calculation results, and experimental results are introduced.
Cryogenic test bench for the experimental investigation of cryogenic injection in rocket combusters under high-altitude conditions
Authors: Rees Andreas , Oschwald Michael
Published: June 2022

Due to current and future environmental and safety issues in space propulsion, typical propellants for upper stage or satellite rocket engines such as the toxic hydrazine are going to be replaced by green propellants like the combination of liquid oxygen and hydrogen or methane. The injection of that kind of cryogenic fluid into the vacuum atmosphere of space leads to a superheated state, which results in a sudden and eruptive atomization due to flash boiling. For a detailed experimental investigation of superheated cryogenic fluids the new cryogenic test bench M3.3 with a temperature controlled injection system at high-altitude conditions was built at DLR Lampoldshausen. First run-in tests as well as several measurement campaigns with liquid nitrogen as the test fluid showed the performance and suitability of the new test bench for the systematical investigation of cryogenic flash boiling. Besides new insights into the flash boiling process of cryogenic liquids, the experimental data of cryogenic flash boiling generated with this test bench provide a comprehensive database for the validation of numerical models and further numerical investigations.
Preliminary Structural Design and Analysis of the Horizontal Cold Box for CFETR 25 kW@4.5 K Helium Refrigerator
Authors: Zhang C J , Zhang Q Y , Zhu Z G , Yao D M , Yang P C , Zong Y W , Chen S X
Published: June 2022

The China Fusion Engineering Test Reactor cryogenic system mainly provides necessary supercritical helium for cooling superconducting coils and structure to transfer the static thermal load and the dynamic thermal load generated during plasma operation mode. According to the conceptual design of CFETR cryogenic system, the cooling capacity at 4.5 K is about 125 kW, with five 25 kW@4.5 K helium refrigerators in parallel. As one of the main components, a horizontal cold box provides a vacuum and insulating working environment for plate-fin heat exchangers, turbines, adsorbers, control valves and pipes. This paper presents a preliminary structural design for the 25 kW@4.5 K helium refrigerator horizontal cold box. The structural strength and static heat leakage of the cold box including support seats are analyzed through the finite element simulation method. The simulation results further verify the rationality and feasibility of the cold box structure design, and provide a certain reference for the subsequent detailed engineering design.
Operational experience with the Proto-DUNE NP02 and NP04 large volume liquid argon cryostats and their cryogenic systems at CERN
Authors: Bremer J. , Chalifour M. , Creus-Prats J. , Fabre C. , Montanari D. , Pezzetti M. , Resnati F. , Nessi M.
Published: June 2022

The far Detector of the Deep Underground Neutrino Experiment (DUNE) will be housed in several large volume (about 12.500 m3) liquid argon cryostats. The design principle of these large cryostats, and of the cryogenic system belonging to them, are investigated through the design, construction and operation of a series of prototype installations.

The Neutrino Platform 02 (NP02) and 04 (NP04) cryostats, placed at CERN, contain DUNE proto-type detectors, each of them housed in an about 600 m3 liquid argon bath. These cryostats, based on the membrane cryostat principle, and their cryogenic systems have been designed according to the DUNE principle. Measurements performed in these test stands shall confirm the foreseen heat loads into the cryostat systems entering via its walls, via detector cabling and via the cold electronics, shall confirm the low temperature gradient over the active detector volume and shall certify the liquid argon purification principle.

This paper introduces the requirements for the NP02 and NP04 cryostats and their cryogenic systems, describes the design principle applied to these two systems and gives an overview of the different modes in which the two systems have been operating. The experimental results are presented and discussed, and “lessons learned” for future installations are dawn.
Assessment of the operation safety margin of the HL-LHC superconducting recombination Dipole D2 in case of helium filling failure
Authors: Rousset B , Bancel F , Besson N , Bon-Mardion M , Claudet S , Goy T , Millet F , Nivelon P , Perin A
Published: June 2022

After the successful completion of the cryogenic performance tests of the He II heat exchanger prototype for the D2 recombination dipole of the future HL-LHC project at CERN, specific measurements were performed to determine the operation safety margin in case of abnormal operating conditions. This is particularly relevant in case of the failure of liquid helium supply in the He II cold source. For nominal operation, the liquid level is regulated at a constant value and it is not necessary to know its value very accurately. However, in case of a partial drying of the heat exchanger due to discontinuation of the helium liquid supply, it is essential to monitor the absolute value of the liquid level to anticipate any cooling malfunction. This paper describes the procedure for an accurate in-situ He II level measurement as well as for the heat loss and mass flow rate estimates in a He II phase separator. The operation safety margins of the He II heat exchanger prototype for the D2 magnet are then analyzed for the different operating conditions considered during the HL-LHC runs in case of non-nominal liquid level in the He II cold source.
Heat loads measurements at the XFEL cold linac
Authors: Ramalingam R , Bozhko Y , Barbanotti S , Schnautz T
Published: June 2022

The European X-Ray Free Electron Laser (EuXFEL) at DESY is in operation since the beginning of 2017. The free electron laser is based on a superconducting linear accelerator that delivers electrons to the undulator section with beam energy up to 17.5 GeV. The linear accelerator consists of 96 cryomodules; each 12 m long module is an assembly of 8 superconducting cavities and one superconducting magnet. This paper focusses on the measurement of the static and dynamic heat loads of the cryomodules assembled in the linac. Heat loads are an important parameter to evaluate the efficiency of the refrigerator system, the quality of the cryomodule assembly and installation and the accelerating cavity performances, being the dynamic heat loads proportional to the cavity quality factor (Q0, the ratio of the stored energy to the dissipated energy). The paper describes at first the procedure to measure the static heat load without beam energy and the dynamic heat loads at different beam energy levels. The measurement results are then summarized and compared with the XFEL design values.
Development of a cryocooler conduction-cooled 650 MHz SRF cavity operating at ∼10 MV/m cw accelerating gradient
Authors: Dhuley R.C. , Posen S. , Geelhoed M.I. , Thangaraj J.C.T.
Published: June 2022

SRF cavities for particle acceleration are conventionally operated immersed in a bath of liquid helium at 4.2 K and below. Although this cooling configuration is practically and economically viable for large scientific accelerator installations, it may not be so for smaller accelerators intended for industrial applications such as the treatment of wastewater, sludge, flue gases, etc. In this paper, we describe a procedure to operate SRF cavities without liquid helium that can be used to construct electron-beam sources for industrial applications of electron irradiation (1-10 MeV electron energy). In this procedure, an elliptical single-cell 650 MHz niobium-tin coated niobium cavity is coupled to a closed-cycle 4.2 K cryocooler using high purity aluminum thermal links. The cryocooler conductively extracts heat (RF dissipation) from the cavity without requiring liquid helium around the cavity. We present construction details of this cryocooler conduction-cooling technique and systematic experiments that have demonstrated ∼10 MV/m cw gradient on the cavity. By straightforward scaling up the cavity length and number of cryocoolers, the technique will provide the complete range of 1-10 MeV electron energy for industrial applications.
Cryogenic testing of a 25 kV RIS bushing
Authors: Fink Stefan , Fuhrmann Uwe , Zwecker Volker
Published: June 2022

High voltage bushings for cryogenic current or voltage leads must master safely the special thermal stress in addition to the high voltage requirements. Resin impregnated synthetic (RIS) bushings have proven their usability for room temperature high voltage application since few years. Such paper free bushings are less hygroscopic than paper based bushings, which can be an advantage for components exposed to cryogenic temperatures on one side and to air conditions on the other. A conventional 25 kV, 2 kA room temperature RIS bushing was assembled to an open bath cryostat and subjected to five thermal cycles. High voltage tests were successfully performed under cryogenic conditions. No degradation of the bushing was found after the thermo-mechanical stress of the fast cool downs and one fast warm up. This paper focuses on the thermal tests.
Low level RF development for ESS high beta cavity test
Authors: Dumbell K , Lewis J , Wheelhouse A , Pattalwar S , Moss A , Corlett P , Goudket P , Hitchen S , Jenkins C , Ellis M , Pendleton M , Smith P , May A , Wilde S , Oates A , Middleman K , Wilson J , Lowe M , Mason D , Sollars P , Pattalwar N , Hornickel P , Mutch J
Published: June 2022

Testing of superconducting cavities requires the use of a Self-Excited Loop or Phase Locked Loop in order to track a cavity’s resonant frequency under the disturbances of micro-phonics. Many laboratories have successfully developed their own Low Level RF solutions and have implemented these using Field Programmable Gate Array at the heart of the digital system. This approach has also been adopted at Daresbury Laboratory. However, the dedicated system was identified as a single point of failure in the complex operational testing infrastructure and an alternative, back-up, system was sought. Rather than duplicate the existing system another approach has been adopted making use of Commercial Off The Shelf hardware with minimal requirement for interconnect to the existing high power system. The solution is based around the NI (National Instruments Corporation) FlexRIO transceiver adapter NI-5782 connected to the NI-7962R FPGA module inside a PXI chassis. This system is capable of working directly at an Intermediate frequency of 37.5 MHz and only requires a simple up-converter / down-converter stage. Testing the high Q (typically 2 × 1010) cavities up to accelerating gradients of 22.5 MV/m has been successful.
Experimental study on the pool boiling heat transfer of slush nitrogen under triple point to atmospheric pressure
Authors: Wang Q D , Jiang Q K , Jin T
Published: June 2022

Slush nitrogen is a solid-liquid two-phase cryogenic fluid, with temperature of about 63.15 K under pressure between the triple point of nitrogen and atmospheric pressure. High-temperature-superconductor (HTS) cables generally require the cryogenic coolant such as subcooled liquid nitrogen. Compared with the subcooled liquid nitrogen, slush nitrogen has lower temperature, higher density and higher heat capacity, and is considered a promising coolant for HTS cables. In order to intuitively understand the boiling heat transfer characteristics of slush nitrogen, a pool of slush nitrogen of 0-30% solid volume fraction was prepared as coolant and was filled into a dewar, and helium was charged to change pressure from triple point to atmospheric pressure. Experiments under different pressure conditions were carried out to obtain the variation of boiling curves. The critical heat flux (CHF) of slush nitrogen was found to be reduced by increasing solid volume fraction, because of denser solid nitrogen with lower heat transfer capacity within the main boiling field. By fitting the result to Kutateladze Correlation which predicts CHF, while considering the influence of subcooling, the improved coefficients applicable for slush nitrogen are obtained with an accuracy of ±10%.
Epoxy Electret: A Remedy for Partial Discharge at Cryogenic Temperature
Authors: Haque Farhina , Park Chanyeop
Published: June 2022

Epoxy-based composites exhibit mechanical compatibility at cryogenic temperatures. Owing to these properties, composites based on epoxy are used as electrical insulators in high temperature superconducting (HTS) power applications. However, the inevitable presence of voids in solid insulators, triple points, and airgaps at high-voltage conductor-insulator interfaces increase electric fields locally. The intensified electric field around these defects and interfaces is the main cause of partial discharge (PD), which is a dielectric challenge for numerous power applications including HTS cables. Recently, electret has been introduced as a promising solution to mitigate PD activities caused by voids and triple points. In this work, we intend to report the PD mitigation performance of electrets fabricated from epoxy resin, which is suitable for cryogenic power applications.