Characteristics Of Processes Research Articles

Separation and capture of CO2 from ambient air using TEPA-functionalized PAN hollow fibers

Solid amine sorbents have potential application in direct air capture of CO2 due to the advantages of low generation energy-demanding, and high adsorption capacity. Although the powdery solid amine sorbents exhibit high CO2 adsorption capacity, large pressure drop still limits their applicability. Structured solid amine are considered as good alternatives to solve this problem, but they still have the bottle-neck of insufficient CO2 adsorption capacity. To this end, we proposed solid amine hollow fiber to address these problems. In this work, tetraethylenepentamine (TEPA)-functionalized polyacrylonitrile (PAN) hollow fibers were fabricated via hydrolyzing nitrile groups on hollow fiber surface and then chemically grafting TEPA on it. The as-prepared PAN-TEPA hollow fiber was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET). In CO2 capture experiment, PAN-TEPA hollow fiber achieved high adsorption capacity under low CO2 concentration (5.07 mmol g−1, 5000 ppm, CO2-N2) source. The adsorption kinetics were studied, and Avrami fractional-order kinetics model fitted best with experimental curve. The adsorption capacities under low concentrations fitted well with Langmuir isotherm. Temperature-vacuum swing (TVS) desorption process was employed to rengenerate PAN-TEPA hollow fiber, and the regeneration conditions were screened. In direct air capture, PAN-TEPA hollow fibers had an adsorption capacity of 2.02 mmol g−1. CO2 Saturated PAN-TEPA hollow fibers could be efficiently regenerated by TVS desorption process. After 11 adsorption–desorption cyclic experiments, the decrease of breakthrough CO2 adsorption capacity is not obvious. Due to their characteristics in CO2 adsorption and desorption processes, PAN-TEPA hollow fiber is a potential sorbent for separation and capture of CO2 from ambient air.

Fluence and Temperature Dependences of Laser-Induced Ultrafast Demagnetization and Recovery Dynamics in L10-FePt Thin Film.

The fundamental mechanisms of ultrafast demagnetization and magnetization recovery processes in ferromagnetic materials remain incompletely understood. The investigation of different dynamic features which depend on various physical quantities requires a more systematic approach. Here, the femtosecond laser-induced demagnetization and recovery dynamics in L10-Fe0.5Pt0.5 alloy film are studied by utilizing time-resolved magneto-optical Kerr measurements, focusing on their dependences of excitation fluence and ambient temperature over broad ranges. Ultrafast demagnetization dominated by Elliott-Yafet spin-flip scattering, and two-step magnetization recovery processes are found to be involved in all observations. The fast recovery time corresponding to spin-lattice relaxation is much shorter than that of many ferromagnets and increase with excitation fluence. These can be ascribed to the strong spin-orbit coupling (SOC) demonstrated in FePt and the reduction of transient magnetic anisotropy, respectively. Surprisingly, the demagnetization time exhibits no discernible correlation with ambient temperature. Two competitive factors are proposed to account for this phenomenon. On the other hand, the spin-lattice relaxation accelerates as temperature decreases due to enhanced SOC at lower ambient temperature. A semiquantitative analysis is given to get a visualized understanding. These results offer a comprehensive understanding of the dynamic characteristics of ultrafast demagnetization and recovery processes in iron-based materials with strong SOC, highlighting the potential for regulating the magnetization recovery process through temperature and laser fluence adjustments.

Differentiating environmental scenarios to establish geochemical baseline values for heavy metals in soil: A case study of Hainan Island, China

Soil heavy metal distributions exhibit regional heterogeneity due to the complex characteristics of parent materials and soil formation processes, emphasizing the need for appropriate regional standards prior to assessing soil risks. This study focuses on Hainan Island and employs the Multi-purpose Regional Geochemical Survey dataset to establish heavy metal geochemical baseline and background values for soil using an iterative method. Geographical detector analysis reveals that parent materials are the primary factor influencing heavy metal distribution, followed by soil types and land use. Heavy metal geochemical baseline values are established for the island's three environments and administrative regions. Notably, a universal geochemical baseline value cannot adequately represent regional variations in heavy metal distribution, with parent materials playing a crucial role in various scenarios. Locally applicable values based on parent material are the most representative for Hainan Island. This study provides a reference framework for developing region-specific environmental baseline values for soil heavy metal assessments.

Improvement of technological processes of cultivation of vegetable crops in the Far East. Review

The results of the selection work of the Primorsky vegetable experimental station, work in the field of seed production of vegetable crops are presented, the characteristics of the negative processes occurring in the arable soils of the region and their removal by the developed ridgeridge technology of cultivation by technical means with a wide base are given. A comparative characteristic of the former and the wide-row version in terms of energy consumption and fuel consumption is givenAuthors´ Contribution: All authors contributed to the planning and setting up the experiment, aswell as in the analysis of experimental data and writing of the article.Based on the results of the selection work of the Primorsky Vegetable Experimental Station for the period 1993-2023, the station bred and released 56 varieties and hybrids of 19 main vegetable crops. The experience of the Primorsky branch of the Federal scientific vegetable center allows organizing production at a modern level, taking into account the rich experience of other regions of Russia. In conditions of monsoon climate and soils of heavy granulometric composition, with a general lack of heat, their fertility is negatively affected by a large number of external factors. To grow vegetables, a set of measures is needed for serious drainage and irrigation reclamation (creation of polder systems with the laying of systematic plastic drainage) against the backdrop of ridge-ridge cultivation technology, fine irrigation system). The developed wide-cut technology and a set of machines make it possible to introduce a resource-saving technology that saves energy costs and fuel.

Scheduling power-to-ammonia plants considering uncertainty and periodicity of electricity prices

Developing affordable and scalable energy storage solutions are essential to decarbonizing power systems. The conversion of renewable electricity into chemical energy carriers such as ammonia has attracted extensive attention from academia and industry. Many Power-to-Ammonia (PtA) plants have been conceptualized and developed worldwide in recent years. The PtA plant is an integration of multiple electrochemical processes, each with a distinct set of operational constraints and cost structure. One of the problems in the operation of PtA plants is the optimal scheduling of the hydrogen buffer in PtA plants considering the operational characteristics of electrochemical processes and the volatility and uncertainty of electricity prices. In this paper, a two-stage Markov-Decision-Process (MDP) approach is proposed. The computational challenges brought by the infinite optimization horizon and non-concavity of cost functions are resolved. The first stage solution is based on the periodic MDP approach, which captures the periodic structure of electricity prices. The second stage solution gives optimal real-time decisions based on a rolling-horizon MDP approach. Numerical results show that the accurate representations of the cost functions and the optimization horizon using the proposed method are necessary, while the linearization of cost functions and the truncation of the optimization horizon lead to notable deviations from the optimality.

Determination of the natural frequencies of the above-ground sections of pipelines transporting an incompressible fluid

Under certain conditions, above-ground sections of pipelines are subject to vibration. Increasing the vibration amplitudes beyond the limits can cause the object to fail. In order to assess the vibration resistance of pipelines and to find the most effective ways of detuning from the resonant frequencies of disturbances, it is necessary to determine the natural frequencies of oscillations and the characteristics of the oscillation processes. The authors of the article developed a mathematical model to determine the frequency of free vibrations of above-ground pipeline sections, taking into account the influence of internal pressure and the velocity of the pumped fluid. As a result, a numerical solution based on the Bubnov-Galerkin method was obtained and a sufficient number of series elements in the approximate solution was determined. The authors performed numerical experiments. These showed that the frequencies should be determined for each section under specific conditions according to the pumping mode.

Solvent extraction of superfine pulverized coal. Part 3. Small angle X-ray scattering characterization

Because of the unique physicochemical textures induced by reduced particle size, superfine pulverized coal presents attractive characteristics in different utilization processes, including solvent extraction. In this work, the synchrotron radiation-based small angle X-ray scattering (SAXS) with high precision was used to quantitatively characterize all the products during the coal extraction process, including raw coal, extract, and residue. In addition, the evolutions of pore structures (solid state) and aggregate configurations (liquid state) were focused on. The results show that the fractal dimensions of pore surfaces are mainly related to the pore sizes and corresponding quantity distributions. When the particle size is less than 14 μm, the comminution induced mechanical effect on the pore surface gradually changes from impact to polish during the superfine grinding. Additionally, the fractal dimension decreases with the decline of particle size and ash content, whilst increases for the lower ranked coals. As for the extraction process, the extraction effect of tetrahydrofuran on anthracite coal is relatively better, while pyridine is more effective for bituminous coal. The diverse driving force caused by particle size effect leads to different radii of the gyration of the extracted aggregates, indicating the selected bituminous coal has active sites that are susceptible to reacting with aromatic compounds, while anthracite has a large number of active sites that accept electrons. Finally, the surface fractal dimension of the extraction residue declines about 2% and 4% for HN and NMG coal respectively, and the decreasing trend declines for larger coal particles. Interestingly, this decreasing trend of bituminous coal is more evident, which indicates the pore surface of bituminous coal is easier to react with solvent. The research sheds light on thoroughly depicting the pore structure of coal and residue at a molecular level, which promotes a better understanding of the solvent extraction mechanisms. The results also provide a new perspective for constructing more comprehensive coal molecular models in the future.

Numerical simulation for peristaltic transport of radiative and dissipative MHD Prandtl nanofluid through the vertical asymmetric channel in the presence of double diffusion convection

This work's primary goal is to give a novel thorough investigation that examines the effects of the temperature- and concentration- dependent electrical conductivity on the peristaltic flow through the vertical asymmetric rotating channel filed with magnetic Prandtl nanofluid saturated in a porous medium. In addition to joule heating, viscous dissipation, and nonlinear thermal radiation, the fundamental characteristics of Brownian motion and thermophoresis processes are also considered when modelling the heat equation. Further, the influences of the double diffusion convection are examined, and the cases of biological scientific assumptions which is known as low Reynolds number and long wavelength are applied. The software Mathematica's built-in command (ND Solve function) is used to numerically solve the consequent nonlinear coupled differential equations system. The main findings showed that as the Soret and Dufour numbers increased, consequently increased the heat resistance, whereas the dissolvent concentrations and nanoparticle volume percentage had the reverse impact.

Volcano-sedimentary interactions – A key to understand Cretaceous paleoenvironments in the Paraná basin (southern Brazil)

The Lower Cretaceous in the Paraná Basin record a large volcanic event (Serra Geral Formation) that covered an active sedimentary system (Botucatu Formation), before the fragmentation of the southern Gondwana. Therefore, the fluvial-aeolian deposits underlying aeolian deposits of residual dunes, were gradually covered by volcanic flows. Intense basic and minor acidic magmatism covered an extensive continental aeolian environment. The interface between the two units shows an aeolian environment during the early stages of volcanism forming deposits and volcano-sedimentary features overlying and underlying the flows. In six outcrops on the southern portion of the current border of Paraná Basin, in Rio Grande do Sul state, these deposits and features were recognized, showing the complexity of the environment and the processes associated with lava flows and sediments. They were formed by the interaction of consolidated or unconsolidated sediments, saturated or not in the water, with basaltic or dacitic flows. Interaction features and deposits synchronous to volcanism (volcanoclastic), later or in intervals between volcanic events (epiclastic) and only cover, with absence of interactions, were identified. Through the distinctive characteristics of the interaction processes between the volcanic rocks and the sediments analyzed in the volcanic-sedimentary features and deposits, the morphology of the aeolian environment of Botucatu Formation could be, by analogy, compared to the current aeolian environments. The proposed paleoenvironment indicates a sedimentary environment with different domains, categorized by their water saturation. The different siliciclastic components found in each domain allowed the generation of different features and volcanic-sedimentary deposits evidencing aspects related to the presence or absence of water among the proposed domains.

ПРОСТРАНСТВЕННОЕ РАЗВИТИЕ КАК ФАКТОР ФОРМИРОВАНИЯ ИНВЕСТИЦИОННОЙ ПРИВЛЕКАТЕЛЬНОСТИ РЕГИОНА

The article examines the importance and role of investments, which are a key factor in the development of the region's economy. The main features of the concept of "investment" are highlighted and characterized. The analysis of the state of the problem is carried out on the basis of statistical data of the Federal State Statistics Service and data obtained from open sources, including official websites. 
 In the course of the study, a brief overview of scientific ideas about the content of the concept of "spatial development" was carried out. It was found that spatial development and investment attractiveness are closely related to each other. It is shown that when developing a spatial development strategy, it is necessary to apply a systematic approach taking into account the manifested interrelations of all elements 
 The interrelation of investment attractiveness and spatial development of the region is revealed on the example of the Voronezh region. One of the main characteristics of investment processes in the region is the structure of investments in fixed assets. The article analyzes data on investments in fixed assets, taking into account the investment activity of small businesses and the volume of investments not observed by direct statistical methods. The analysis of the state of the problem is carried out on the basis of statistical data of the Federal State Statistics Service, data obtained from open sources, including official websites. In the course of the study, investments in fixed assets in the Russian Federation and in the Voronezh region were analyzed. The assessment of the level of investment attractiveness is given, the main tasks of the coordination body for the investment development of the Voronezh region are briefly highlighted.
 The main factors that influenced the positive dynamics of investments are highlighted, as well as weaknesses in the strategic direction of enhancing investment activity in the region are identified. 
 From the results obtained, it can be concluded that the state of investment activity in the Voronezh region has unstable growth trends, in particular investments in fixed assets. The structure of industrial production is mainly focused on local markets.
 In conclusion, the main aspects of the relationship between investment attractiveness and spatial development of the region are summarized closely, closely related to each other. Recommendations are given to increase the investment attractiveness of the Voronezh region for further spatial development of the region. As a result of the study, the main factors that influenced spatial development as a factor in the formation of the investment attractiveness of the Voronezh region were identified.

Research on the effect of low-sulphur marine fuels on the dynamic characteristics of a CI engine

The implementation of low-sulphur, so-called modified marine fuels into operation requires prior laboratory engine tests to assess the energy, emission and structural effects of their usage. This type of research are carried out on the test bed of a diesel engine as a small-scale physical model that reproduces the adequate design and process (parametric) features of a full-size marine engine. Their key stage is to determine the energy characteristics of the engine in the steady state of operation determined on the basis of the analysis of the developed indicator diagram and the dynamic characteristics of the transient processes from idling to the reference steady state of load - and vice versa. In this way, the basic diagnostic parameters of the fuel usable quality are determined: the rate of pressure increase in the cylinder and the average deceleration of the engine crankshaft within the strenuous transient process. This article presents representative results of this type of research carried out on six different, low-sulphur marine fuels used to feed marine engines.

Critical View on Reliability of One-sample t-Test as a Tool for Business Decision-making

A lot of organizations rely on t-test and hypothesis testing to determine if they can bank on the observation results, they are obtaining, or if it is just unexpected luck or random happenstance. Small businesses find this statistical technique to be an economical and precise way to compare observations or two population groups for numerous different scenarios without resorting to expensive live test scenarios. From testing employee job satisfaction by gender to better understanding economic growth in one city compared to another to identifying if a certain customer segment spends more on specific products, the t-test is a useful statistical technique for businesses. This research suggests a structured analysis aimed to find out the limitations of the one-sample t-test. The results obtained prove that typical characteristics of business processes and the commonly used techniques in empirical research have significant influence on the reliability of the classic one-sample t-test for decision-making, and its nominal error probability is underestimated. In these regards, a set of simple and effective recommendations is given for researchers and decision-makers in order to avoid fatal mistakes in their activities. This piece fills the gap, which is important for further research in economic and managerial statistics.

Use of E-Recruitment Process with the Comparison of Traditional Recruitment Process in Bangladesh: A Case Study on BRAC Bank Ltd.

This paper discusses the comparison of e-recruitment and traditional recruitment processes and their merits and demerits. The figure of this process is arranged in such a way that in the static equilibrium, the e-recruitment process takes the horizontal position, while the traditional recruitment process takes the vertical position. Here are presented the characteristics of both e-recruitment and traditional recruitment processes that are used in Bangladesh for attracting and selecting qualified candidates through the analysis of a case of BRAC Bank Ltd. Obtained results proved to be in accordance with the motion of the real physical system. The difference between the two processes is illustrated in the figure and the merits and demerits of the two processes are discussed in the table.

Joint optimization of fleet-level sequential selective maintenance and repairpersons assignment for multi-state manufacturing systems

Due to limited maintenance resources, the joint optimization of fleet-level selective maintenance and repairpersons assignment aims to determine the optimal subset of maintenance actions for each repairperson to ensure that manufacturing systems in the fleet complete subsequent missions. However, related studies ignore the uncertain maintenance duration and flow dependency (a stochastic dependency caused by dynamic material flow) resulting in overestimation of system reliability and total profit. Therefore, this paper proposes a novel joint optimization model of fleet-level sequential selective maintenance and repairpersons assignment under flow dependency and uncertain maintenance duration. The model requires identifying a subset of maintenance actions, assigning the selected maintenance actions to repairpersons, and planning sequence of maintenance actions executed by each repairperson. Moreover, the degradation model of multi-state machines under flow dependency is established by analyzing dynamic characteristics of production processes. Further, the reliability of multi-state manufacturing systems considering the interaction among repairpersons, flow dependency, and uncertain maintenance duration is incorporated into the optimization model. The objective is to maximize the total profit under predetermined system reliability thresholds. Then, the optimization problem is solved by a tailored genetic algorithm with segment-based evolution strategy. Finally, numerical examples are given to verify the effectiveness of the proposed method.

Effects of temperature and pressure fluctuations on exergy loss characteristics of hydrogen auto-ignition processes

Intake temperature and pressure fluctuations prior to main ignition are one of the reasons affecting the efficiency of internal combustion engines. In this study, the effects of temperature and pressure fluctuations with varied amplitudes and frequencies on the exergy loss of hydrogen auto-ignition processes were numerically investigated in an adiabatic constant-volume system at engine-relevant conditions. The results revealed that the increase in temperature fluctuation amplitudes primarily decreases the exergy loss due to chemical reactions, and the exergy loss due to incomplete combustion remains unchanged. Specifically, the total exergy loss is reduced by approximately 1.5% with a temperature fluctuation amplitude of 100 K at a frequency of 2 ms−1. Furthermore, with the same temperature fluctuation amplitude, increasing the frequency of temperature fluctuation from 2 ms−1 to 7 ms−1 leads to a 0.7% increase in the total exergy loss. On the other hand, the effects of pressure fluctuation on the exergy loss of hydrogen auto-ignition processes are negligible compared with those of temperature fluctuation. Through chemical kinetic analysis, it is found that temperature fluctuation promotes the consumption pathway of O2 to generate OH, rather than the collision with H to produce HO2. Consequently, the reduced mole fraction of HO2 inhibits the related HO2-consumption reactions, including HO2+HOH + OH and HO2+HO2H2O2+O2. Moreover, with temperature fluctuation, due to the lower fraction of third-body collision molecules, H2O, the reactivity of the third-body reaction, H + O2+M=HO2+M, is decreased. The reduced reaction rates of these reactions lead to decreased total exergy loss, indicating that the fuel energy conversion process may benefit from temperature fluctuation.

MORPHOMETRIC CHARACTERISTICS OF THE MANDIBULAR CONDYLAR PROCESSES

Aim: to study the morphometric characteristics of the mandibular condylar processes to identify patterns and their classification. Materials and Methods: a study of 49 skeletonized and certified mandibular preparations was performed using a caliper and a depth gauge. During the study of the material, the forms and the main morphometric parameters of the condylar processes were determined and analyzed. Statistical data processing was carried out using the Microsoft Excel program. Results: The study of certified biological material yielded the main morphometric and morphofunctional parameters of the mandibular condylar processes. We revealed characteristic differences in the anatomical structures of the studied preparations. The main variants and types of combinations of forms of condylar processes were singled out: oval, hook-shaped, diamond-shaped, L-shaped. The lowest asymmetry index is characteristic of a combination of oval and diamond–shaped forms - 2.44%., and the highest asymmetry index is characteristic of diamond–shaped and L-shaped forms of condylar processes - 7.13%. Conclusion: The presented data can help practitioners to more accurately determine the target point for Gow-Gates anesthesia; to take into account the nature of the influence of structural changes in the joint on other elements of the dental apparatus, thus preventing functional diseases of the temporomandibular joint. The methodology of studying the main morphometric parameters on skeletonized preparations of the lower jaws can be adapted for the examination of living persons using diagnostic radiology.

A comprehensive field investigation of the dynamic break-up processes on the Chaudière River, Quebec, Canada

Abstract The Chaudière River in Quebec, Canada, is well known for its frequent ice jam flooding events. As part of a larger watershed research program, an extensive field campaign has been carried out during the 2018–2019 and 2019–2020 winter seasons to quantify the spatiotemporal characteristics of the break-up processes along the Chaudière River. The results showed that mid-winter ice jams have formed in the Intermediate Chaudière and persisted until spring break-up. Spring break-ups were initiated in the Upper Chaudière, and then, almost simultaneously, in the Intermediate and Lower Chaudière reaches. The break-up in the Intermediate Chaudière usually lasts longer than the rest of the river since the slope is much milder, and the occurrence of mid-winter ice jams has been seen to delay the ice clearing. A reach-by-reach characterization of the cumulative degree day of thawing and discharge thresholds for the onset of break-up has been identified. During the field campaign, 51 ice jams were documented together with their location, length, date of formation, and the morphological feature triggering jam formation. Break-up patterns, hydrometeorological thresholds of ice mobilization, and ice jam sites identified in this study can serve as a basis for the implementation of an early warning system.

A study of cloud microphysical processes and a mesoscale environment in a heavy rainfall case over Yan’an

A cloud-resolved numerical simulation was carried out for an extreme rainfall case in Yan’an, a city in arid and semi-arid regions in northwest China, on 3–4 September 2021, by using Mesoscale Weather Research and Forecasting Model. The Auto Weather Station and Doppler radar were applied to verify simulated results. The characteristics of mesoscale cloud environment and cloud microphysical processes were analyzed. Then, the quantitative rainwater mass budget and latent heat budget of microphysical conversions about water condensates calculated in Yan’an. The possible mechanism by which cloud microphysics affected the rainstorm was investigated and discussed. It was found that: (1) There was positive feedback between mesoscale cloud environment and cloud microphysical processes, especially diabatic heating processes due to ice phase particles conversions. (2) The process of snow conversions processes was the most important process of this heavy rainfall in Yan’an. It not only promoted the production of rain, but also contributed to the enhancement of updraft through latent heat release and produced positive feedback to other microphysical processes in cloud. (3) Heavy rainfall in arid regions of China is mostly cold-type precipitation, mainly manifested by snow-dominated cloud microphysical processes producing deep convection.

МОДЕЛИРОВАНИЕ СИСТЕМЫ ОЧИСТКИ СТОЧНЫХ ВОД ЖИВОТНОВОДЧЕСКИХ ФЕРМ НА ОСНОВЕ СЕТЕЙ ПЕТРИ

The development of animal husbandry on an industrial basis causes a sharp increase in the amount of highly polluted wastewater, the purification and disinfection of which is one of the most important tasks when deciding on their use in agriculture as fertilizer or discharge into reservoirs or irrigation fields. The effectiveness of such systems is achieved with the help of new ways of processing information and mathematical characteristics of technology processes. Based on the study of the main methods of creating discrete chemical and technological systems (CTS), the expediency of using the design of Petri nets (SP) to simulate the process of wastewater treatment of livestock farms (OSWF) was developed. To characterize the system, we use N–schemes, which are based on the mathematical system of the joint venture, which can form a network structure both in analytical form for automating work during analysis, and in graphical form to create visibility of the created model. Analyzing technological and chemical processes, it is important to take into account the formality condition of N–circuits, which assumes that the circuits do not take the properties of simulated systems in time, since the timing of the transition is taken to be zero. We took into account these conditions and proposed updated Petri nets that are focused on the analysis and simulation of discrete CTS, by changing the time delay of labels on transitions and positions, as well as by enabling transitions that are in priority. We have created a model in the form of a modified updated Petri net (SME). With the help of SCADA TRACE MODE technologies, we have developed a whole software package for the control system in the process of OSWF. This system can perform dispatching monitoring of the main parts of the control apparatus, as well as stop and analyze and monitor its condition, this is feasible both in general and within the framework of forecasting the occurrence of emergency situations.

Optimal Control of Technological Processes

The paper formulates conditions under which the roots closest to the imaginary axis (critical roots) of the characteristic equation of a linearized system are real for the maximum possible degree of stability of the closed-loop control system of a technological process with pure delay. For the parameters of the controllers corresponding to the maximum degree of stability, these roots are multiples. Their multiplicity order is one more than the number of coefficients in the transfer function of the controller. It is demonstrated that for a typical technological control object, these conditions are satisfied for all “serial” control laws. This allowed for obtaining analytical expressions for optimal settings and limiting degrees of stability as functions of object parameters for typical dynamic characteristics of technological processes. The paper considers the problem of robust stability for control systems with an object containing pure delay. It has been proven that in the maximum stability problem, the operations of maximizing over controller parameters and minimizing over the set of possible object parameters can be interchanged. Therefore, selecting robust settings amounts to determining the minimum of the maximum stability over the set of possible object parameter values. Controllers with such settings are suitable, without modification, for a whole class of technological processes.