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Research subject. Volcanogenic formations of the northern part of the Tagil megazone.Material and methods. Volcanites of the Tagil paleo-island arc system and its frames were studied, including basalts and andesibasalts of the following formations: Khomas’inskaya O1-2, Shemurskaya O3-S1, Pavdinskaya S1, Imennovskaya S1-2, Turinskaya S2-D1, Perevozskaya D1, Krasnotur’inskaya D1, Limkinskaya D2-3, as well as dolerites of the Ivdel complex D3. Silicate (XFA) analyses and determination of rare elements by ICP-MS method were performed. The obtained data was analyzed using discrimination and spider diagrams, as well as indicator geochemical parameters.Results. The geochemical parameters reflecting the degree of depletion of the host rocks of magmatic chambers, as well as the influence of fluids released during the dehydration of rocks of subducted slabs, quite definitely demonstrate an increase in the role of subducted material in the composition of island-arc magmas. This allows the onset of the subduction process, sharp changes in the conditions of its functioning and the time of its completion to be determined.Conclusions. The obtained geochemical data confirms the existing concepts about the onset of the subduction process at the end of the Middle – beginning of the Upper Ordovician, restructuring (jumping?) of the subduction zone in the Lower Devonian and completion in the Upper Devonian.

The increase in the transit and carrying capacity of cargo intensive sections and directions of railways is achieved by introducing into circulation of cargo trains of increased weight and length, which in turn leads to a change in longitudinal dynamics of movement and emergence of additional loads on rolling stock and the railway track.In this regard in relation to Russian conditions, to ensure the required volumes of transportation with a preset level of safety, it is necessary to revise the current standards designed for maximum longitudinal compression forces of 50 tf, which are currently more than doubled in heavy trains.Based on the analysis of existing regulatory documents, domestic and foreign experience, it was possible to substantiate the necessity to improve the longitudinal dynamics of trains and to propose some ways to achieve it. are proposed. The simulation of collision of a free running platform wagon with standard draft gears of Sh-1-TM type with a gondola cars’ cut also equipped with standard draft gears of Sh-1-TM type was carried out to identify accident modes. The study has allowed to conclude on the expediency of increasing the energy intensity of draft gear through new design solutions, as well as on reducing longitudinal forces through adoption of floating centre beams.

In this work, we analyse and structure the information on the distribution of noble metals during pyrometallurgical processing of copper-sulphide and copper-nickel concentrates, available in domestic and foreign scientific sources. The data on the influence of oxygen partial pressure in the system and, consequently, the matte composition, process temperature, and the phase composition of slag on the distribution of platinum group metals, gold, and silver between the smelting products were analysed. Broad-ranging information on the distribution of the examined metals between matte and slag in the processing of copper-sulphide and copper-nickel concentrates was studied. It was established that the distribution of noble metals between the products of smelting using modern analytical methods is still in its early stages. Contradictory information on the behaviour of gold, silver, and platinum group metals during the pyrometallurgical processing of copper-sulphide and copper-nickel concentrates is presented in literature due to the variations in the experimental procedures, preparation, and analysis of test samples, and, as a result, further interpretation of the obtained results. Furthermore, no data on the influence of such technological parameters as magnetite content in the slag phase, the relationship between copper and nickel in the initial furnace charge and obtained mattes on the distribution of gold, silver, and platinum group metals between the products of smelting are available. In addition, no information on the distribution of noble metals during the pyrometallurgical slags depletion obtained in oxidative smelting of copper-nickel production has been published. Thus, it was decided to perform further research on establishing optimal technological conditions for oxidising smelting of copper-sulphide and copper-nickel concentrates, as well as pyrometallurgical depletion of slags, allowing for the highest extraction rates of noble metals into the target product.

A study of the geochemical features and isotopic (Sm‒Nd and U‒Pb) age of dolerites of the Ivdel complex on the eastern slope of the Northern Urals within the Tagil island-arc mega zone has been carried out. It was found that the magmatic formations composing it are of Famennian age and, therefore, were formed after the closure of the subduction zone. The rocks of the Ivdel complex show a similarity to volcanics of both convergent and divergent settings and were likely formed from the products of partial melting of the depleted supra-subduction upper mantle. Famennian hypabyssal–subvolcanic and volcanogenic complexes, similar to the Ivdel one, are also known in island-arc blocks in the Subpolar and Southern Urals.

The Devonian strata of the Tagil Megazone were studied on the eastern slope of the Northern Urals. It was established that Devonian sedimentary-volcanogenic formations were formed within three paleoenvironments: the shelf zone of the extinct Silurian island arc, the intra-arc trough, and the active island arc. The volcanics are similar in composition to the modern island-arc rocks. This zoning was disrupted during the Givetian owing to the formation of grabens and the eruption of basalts with intraplate geochemical characteristics. The volcanic island-arc activity was renewed in the late Givetian and the early Frasnian. The evolution of the island arc was completed in the late Frasnian–early Famennian owing to its accretion to the continental margin.

To increase the competitive advantages of rail freight transportation, the long-term development program of the Russian Railways provides for an increase in the speed of freight trains. The design speed of freight cars currently operating on the railway network is mainly 120 km/h, and the permitted speed is limited to 90 km/h. One of the possible solutions to the problem is the introduction of freight cars with an increased speed. At JSC “VNIIZHT” and JSC “VNIKTI”, work is being carried out on the selection of structures, the development of safety requirements, theoretical and experimental studies of freight traffic at increased speeds. In 2017—2018 at the Belorechenskaya—Maikop high-speed test range of the North Caucasian Railway, specialists of JSC “VNIIZHT” carried out running tests of a prototype of a platform car for transporting containers with a design speed of 160 km/h, developed by JSC “VNIKTI”. In the design of the platform car, a bogie is used, which is an analogue of the bogie of trailed cars of electric trains ED4 and ED9, with the selection of the stiffness of the springs in the spring suspension steps to comply with the difference in the level of the automatic coupler from the rail head in the “container” and “gross” modes. Analysis of the results of running tests allows determining the ways to improve the design of the bogie. To select design solutions for the purpose of ensuring safety, a review of the studies of domestic scientists aimed at studying the dynamic properties of railway rolling stock with various designs of the carriage part was carried out. Tests were carried out on prototypes of rolling stock having different elastic-dissipative connections in the “body-bogie-wheelsets” system. Based on the results of the analysis, design solutions have been determined that allow achieving satisfactory dynamic qualities for a freight car at a speed of up to 140 km/h. The adopted design solutions were tested on the basis of the results of theoretical studies of the dynamic properties of a platform car with a new bogie, carried out by the method of computer simulation. Increasing the flexibility of the spring suspension and the horizontal connection of the body with the bogie made it possible to improve the dynamic qualities of freight cars. To assess the safety during certification, it is required to develop a standard that would take into account the design features of car bogies, designed for increased speed.

In the context of the life-extension program for the No. 3 unit of the Smolensk NPP, the life-exhausted RBMK-1000 control and protection system, the safety control systems of the power unit, and the analog-relay control apparatus of the technological equipment of the block control board (reactor and turbine departments) have been replaced with systems and software-hardware suites (SHS) developed by NIKIET. NIKIET has completed the full cycle of work from the structural development of the systems and SHS to implementation followed by follow-up support services. Based on experience in modernization of special RBMK CPS and SCS-T systems and the process control and protection systems of the technological equipment of reactor installations developed by NIKIET, a unique automated digital control system with a single multi-level and decentralized structure of a complex of technical means was created, which secures not only safe and reliable operation of the entire power unit but also the fulfillment of key requirements of the system. Currently, the fundamental solutions implemented in this system are used as standards for the development of automated monitoring and control systems for other facilities, specifically, reactor installations with fast reactors (BREST, MBIR).

Introduction. The problem of fire and explosion safety of liquefied hydrocarbon gas transportation arose in the 1970s. The task was set to design new generation tanks having improved technical and economic parameters and indicators to ensure fire and explosion safety. The co-authors have conducted the analysis of regulatory documentation covering the fire and explosion safety of hydrocarbon gas transportation tanks, which shows the absence of any unified policy in the design of cars designated for hazardous cargoes. Hence, a number of models, having no or insufficiently effective protective devices, are produced. Therefore, the issues of fire and explosion safety were understudied in the earlier research works on design of railroad cars, and the problem has not been resolved. Principal actions aimed at the fire and explosion safety of hydrocarbon gas transportation tanks were implemented by the Russian University of Transport (MIIT). Statistical information on fire hazardous failures and fleet tank accidents, as well as their detailed investigation has been collected. Tank barrel vulnerabilities have been identified; reliability and durability assessment methods have been developed. Priorities for improving the pressurized tank design are outlined. The following items of work have been performed: ● analysis of statistical data on hazardous cargo transportation accidents, ● development of fire hazard emergency scenarios; ● improvement of “Railroad car analysis and design regulations”, ● development of mathematical models designated for the analysis of tanks, ● identification of an unstable temperature field inside a tank barrel, if in the seat of fire, using non-linear heat conduction equations and the finite element method (FEM), ● identification of the stress-strain state of a tank barrel during a fire. Conclusions. Following the completion of the work performed by the Russian University of Transport (MIIT), hydrocarbon gas tanks have obtained a better barrel emergency impact protection. A unified policy in the design of cars for hazardous cargoes is needed and regulatory documentation requirements must be harmonized.

Relevance and methods. The article considers the possibility of using the analysis of digital images for a comprehensive assessment of the physical characteristics of grain: vitreous and linear dimensions.Results. A comparative characteristic of instrumental and organoleptic methods for determining these indicators by the following criteria is given: stability of results, speed of measurements and data processing. An algorithm has been developed that combines the ability to programmatically determine glassiness and linear dimensions of wheat grains based on their digital images. A relationship was found between an increase in the vitreous nature of the sample and an increase in the stability of the results.

The chronic kidney diseases are recognized as one of leading problems of modern health care due to high prevalence and unfavorable prognosis. The article considers modern classification of predictors of chronic kidney diseases. It is emphasized that none of known modern classifications of chronic kidney diseases predictors don't take into account medical care accessibility to patients in disease condition as a predictor. It is proposed to consider accessibility of medical care from perspective of macrolevel social factors that represent the most widely background health predictors. The original typology of accessibility of nephrological medical care to patients with chronic kidney disease is proposed, which is implemented through prevention and/or minimization of predictors of the onset of chronic kidney diseases, management of disease progression and nephroprotection modifiable predictors, and renal replacement therapy for patients with chronic kidney disease. The one of reasons of limited accessibility of renal replacement therapy for patients with chronic kidney diseases is transportation problem that is solved in the Saratov region through organization of transportation of dialysis patients and development of domiciliary methods of renal replacement therapy. The restriction of medical care accessibility to patients is considered as an obligatory predictor of the onset, progression and unfavorable prognosis of chronic kidney diseases.

For the first time, the time of completion of the formation of calc-alkaline volcanic complexes of the Devonian Island Arc (Franian) in the Northern Urals was determined. It is shown that the late Devonian volcanic rocks of the Limka series have geochemical characteristics that bring them closer to the rocks of developed island arcs and active continental margins. The detected delay of the final episode of calc-alkaline volcanism in the Northern Urals in comparison with the similar event in the southern Urals may be due to the oblique nature of the subduction.

The date of cessation of calc-alkaline volcanic complex accumulation within the Devonian (Frasnian) island arc in the Northern Urals was determined for the first time. It was demonstrated that the geochemical characteristics of the Late Devonian volcanic rocks of the Limka Formation are similar to those of the rocks of mature island arcs and active continental margins. A certain delay in the final episode of the calc-alkaline volcanism in the Northern Urals as compared to a similar event in the Southern Urals is probably due to oblique subduction.

Absolute differential cross sections for elastic $p^7$Be and $p^8$B small-angle scattering were measured in inverse kinematics at an energy of 0.7 GeV/u at GSI Darmstadt. The hydrogen-filled ionization chamber IKAR was used as an active target to detect the recoil protons. The projectile tracking and isotope identification were performed with multi-wire proportional chambers and scintillation detectors. The measured cross sections were analysed using the Glauber multiple-scattering theory. The root-mean-square (rms) nuclear matter radii $R_{\rm m} = 2.42 (4)$ fm for $^7$Be and $R_{\rm m} = 2.58 (6)$ fm for $^8$B were obtained. The radial density distribution deduced for $^8$B exhibits a proton halo structure with the rms halo radius $R_{\rm h} = 4.24 (25)$ fm. A comparison of the deduced experimental radii is displayed with existing experimental and theoretical data., 18 pages, 6 figures. arXiv admin note: text overlap with arXiv:1803.02044

Introduction. The work is devoted to the results of many years of research to ensure the fire and explosion safety of tanks for liquefied petroleum gases, conducted by the Moscow state University of Railways (MIIT), together with other organizations.Methods. On the basis of statistical data, the main scenarios of emergency situations were determined.Experimental and theoretical studies of the behavior of tanks under emergency conditions associated with dynamic and thermal effects were carried out. Numerous experiments were carried out both on full-scale samples and on models using the theory of similarity. The results of the ex¬periments are used both for verification of theoretical models and for specification of parameters of the calculation schemes.The mathematical models developed in the framework of theoretical research were implemented in the form of a package of computer programs and used later to select the parameters of the means of protection.Results. In terms of protection against thermal effects, the following were proposed: safety valves, fire-retardant coatings, upgraded versions of control, drain and safety valves using design solutions adopted in nuclear engineering. In particular, the use of fire-resistant coatings SGKprovides an increase of 2.5-3.5 times the time of the accident-free stay of the tank in the fire.A new layout of the drain-filling pipes is recommended, which significantly reduces the proba¬bility of breakage of the elements of the drain-filling fittings. The design of safety arcs and nodes for connection of arc elements with the shell is proposed.Conclusion. On the basis of the whole complex of the conducted researches the family of tanks for the transportation of liquefied hydrocarbon gases was developed, the production of which was carried out at the enterprises of Russia, Ukraine, Japan, Poland.However, there is a problem of contradictions in the regulatory documentation on the issues of fire and explosion safety of tanks, which requires the formation of a unified technical policy in this area.

Results of investigations of the angular and energy distributions of prompt neutrons from 239Pu fission observed on WWR-M type research reactor (Gatchina) are presented. Peculiarities observed in both angular and energy distributions of prompt neutrons can be explained by assuming the existence of neutrons emitted near the instant of fissioning nucleus rupture. Anisotropy of the angular distribution of prompt neutrons in the frame of the center of mass of fission fragments (ψ(0°)/ψ(90°) ≈ 1.07–1.09) should also be taken into consideration.

Cambrian igneous formations in the Northern Urals were identified and described for the first time. It was established that the Timanide orogeny terminated in the Early Cambrian and was followed by continental rifting above a mantle plume in the Late Cambrian.

An experiment devoted to studying neutron–neutron angular correlations in the slow-neutroninduced fission of 233U, 235U and 239Pu nuclei was performed. The experimentally determined angular dependence of the number of neutron–neutron coincidences was compared with the results of a Monte Carlo simulation for various values of the neutron-detection threshold in the range between 490 and 2080 keV. It was found that the experimental angular distributions in question can be described well under the assumption that 2% to 5% of all prompt fission neutrons are emitted isotropically in the laboratory frame. Probably, such neutrons can be interpreted as so-called scission neutrons directly associated with the nuclear-rupture instant. Energy distributions of this component were also obtained from the present analysis.

It is shown that the Riphean sediments of the Bashkir and Isherim anticlinoria of the Ural mobile belt were formed in different settings. Sediments of the Bashkir Anticlinorium are autochthonous and were formed in the eastern (in present-day coordinates) Baltica from proximal siliciclastics, whereas the complexes of the Isherim Anticlinorium did not belong to it. Geochemical features of the Middle and lower Upper Riphean metapelites of the Isherim Anticlinorium and U–Pb isotope ages of detrital zircons from sandstones suggest that their provenances were the northern and northwestern parts of Baltica. In the Late Riphean (?)–Vendian, the Isherim block migrated along the Timan margin of Baltica into the present-day position.

The U–Pb isotope data and corresponding ages of detrital zircons from rocks of the basal complexes of the Uralides of different segments of the Ural Fold Belt are considered. It was established that complexes of ancient domains of the East European Platform (Volga-Uralia, Sarmatia, Kola, etc.) seem to have been the main provenance areas of the clastic material for the Southern, Middle, and Northern Urals. This means that there were relatively remote and local (igneous formations of the pre-Uralides) provenance areas. Rift rock associations of the Uralides of the Subpolar and Polar Urals were formed mainly through erosion of local provenance areas (predominantly, Late Riphean–Vendian island-arc and orogenic magmatic complexes of the Proto-Uralides–Timanides). Detrital zircons of Riphean age dominate in rocks of the basal complexes of the Uralides. A source for them could have been rock complexes of Svecofennian-Norwegian Orogen and Cadomides of the Scythian-Turan Plate, intraplate magmatic formations, and metamorphic complexes, as well as blocks accreted to the margin of the East European Platform in the Late Precambrian–Cambrian and later detached and displaced during the Ordovician rifting and spreading. In general, the basal complexes of Uralides were formed owing to supply of clastic material from both remote and local sources. Despite the appearance of information of a totally new level (U–Pb isotope ages of detrital zircons, their Lu–Hf systematics, and the distribution features of rare earth and trace elements), the contribution of these sources to the formation of the Late Cambrian–Early Ordovician clastic strata is hardly possible at present to evaluate.

The article is devoted to autonomy of patient as applied to postmortem donors of organs. The conclusion is made on the basis sociological approach and analysis of legal concepts of «medical service», «medical intervention» and «patient» as related to postmortem organ donorship, about priority of assessment of this particular issue. The attempts of applying regulations of the law on funeral business to postmortem organ donors is inadmissible. The suggestion is developed to consider consent presumption of posthumous organ donorship as a form of transition from autonomy of particular patient to autonomy of society given population support.

Collisional and transport parameters for Cu are computed using the average atom model. Transition metals such as copper are difficult to model within the framework of the average atom model due to the presence of a narrow band of 3d electrons that mix and hybridize with the broad 4s band of nearly-free electrons. With electron temperature increasing, the 3d electrons play a key role in the thermodynamics and transport properties of Cu (Lin et al 2008 Phys. Rev. B 77 075133), as well as the stability of the lattice (Loboda et al 2011 High Energy Density Phys. 7 361). In this work, the average atom model was used to track the average energy of the 3d band and its evolution with electron temperature. At room temperature, its center is at ∼6 electron volts (eV), a few electron-volts below the Fermi energy, and with electron temperature increasing it sinks relative to it. At electron temperature of about 8 eV the 3d electrons leave the conduction band and become bound. A long-standing problem related to the average ion charge observed by conduction band electrons is addressed and successfully resolved. A work-around has been found that predicts the correct average ion charge, Z ˉ , by formally introducing a third group of electrons: quasi-bound electrons. Benchmarking with published data is made that shows good agreement.

New data on composition and age of Precambrian granites and volcanic rocks in the southern part of the Lyapin structure (Northern Urals) are considered. The geochemical features of the igneous rocks are similar to those of the rocks formed in both divergent and convergent environments. In the Late Precambrian (583–553 Ma), the investigated area is assumed to have been a part of the active margin above the mantle plume.

Single-phased La 0.95 Ln 0.05 InO 3 ( Ln – Dy, Ho), La 0.90 Dy 0.05 Ho 0.05 InO 3 , LaInO 3 ceramic samples as well as the La 0.95 Ln 0.05 In 0.98 Sb 0.02 O 3 ( Ln – Dy, Ho), La 0.90 Dy 0.05 Ho 0.05 In 0.98 Sb 0.02 O 3 , LaIn 0.98 Sb 0.02 O 3 samples with additional impurity LaSbO 3 phase were prepared by solid-state reactions method. Their excitation and photoluminescence (PL) spectra were measured at room temperature. It was established that PL bands intensity of spectra obtained for samples of nominal composition La 0.95 Dy 0.05 In 0.98 Sb 0.02 O 3 , La 0.95 Ho 0.05 In 0.98 Sb 0.02 O 3 , La 0.90 Dy 0.05 Ho 0.05 In 0.98 Sb 0.02 O 3 is much higher than that of single-phase La 0.95 Dy 0.05 InO 3 , La 0.95 Ho 0.05 InO 3 , La 0.90 Dy 0.05 Ho 0.05 InO 3 solid solutions. It may be probably explained by sensitizing effect of Sb 3+ ions on Dy 3+ , Ho 3+ ions photoluminescence. Although it can’t be excluded that the reason could be higher PL of Dy 3+ and Ho 3+ ions in impurity matrix than in LaInO 3 -based matrix. It was observed in the PL spectrum of La 0.90 Dy 0.05 Ho 0.05 In 0.98 Sb 0.02 O 3 sample that under the excitation by λ ex = 320 nm an intense simultaneous emission of blue, green and yellow light took place.

Angular and energy distributions of prompt neutrons from the spontaneous fission of 252Cf have been measured. The yield of “scission” neutrons has been estimated by comparing the measured distributions with calculations within the model of emission of neutrons from completely accelerated fragments. It has been shown that the best description of measured angular and energy distributions of fission neutrons is achieved under the assumption that neutrons with a higher (about 6–8%) probability are emitted along the fission axis in the center-of-mass system of fission fragments.

We analyzed the distribution of wide range of trace elements in low-carbon shales of various Riphean, Vendian and Lower Paleozoic lithostratigraphic units of the South, Central, and southern part of the Northern Urals (Satka, Bolshoy Inzer, Suran, Yusha, ZigazinoKomarovo, Vels, Buton, Bezgodovo, and other suites). It was determined that they significantly differ in content of the trace elements. In the most cases, the concentration of trace elements in these shales is roughly comparable with those found in well-known geochemical units, such as the Post-Archean Australian Shale (PAAS), or is lower. Alternatively, obtained data showed significant differences between the Urals low-carbon black shales and the Vendian and Cambrian black shales from China, and other black shale formations, characterized by higher concentration of many trace elements. We consider the probable important role of the geodynamic position of black shale formation, variation in the bioproductivity, association with specific rock complexes, and extent of secondary transformations in variability of geochemical composition of the black shale sediments.

The Tagil structure representing a large fragment of the Paleozoic island arc on the eastern slope of the Urals has been sufficiently well studied in its southern part (Middle Urals). In contrast, reliable data on the age and geochemical properties of various, including granitoid, rock complexes available for its northern part are scarce. The first data on the U–Pb LA–ICP–MS age of zircons from quartz diorites of the Man’ya massif of the Petropavlovsk Complex (436 ± 3 Ma, MSWD = 1.3), tonalites of the same complex (439.4 ± 1.3 Ma, MSWD = 1.3), granites of the Yuzhno-Pomur massif of the Severorudnichnyi Complex (422.4 ± 3 Ma, MSWD = 1.5), and titanite of the same massif (423.4 ± 4.4 Ma, MSWD = 0.84) have been obtained. Based on these data combined with the geochemical properties of the host rocks, the conclusion that they were crystallized at the initial stages of the formation of comagmatic volcanic series is supported; by their composition, granitoids correspond to island arc igneous rocks.

The absolute differential cross sections for small-angle proton elastic scattering off the nuclei $^{12,14-17}$C have been measured in inverse kinematics at energies near 700 MeV/u at GSI Darmstadt. The hydrogen-filled ionization chamber IKAR served simultaneously as a gas target and a detector for the recoil protons. The projectile scattering angles were measured with multi-wire tracking detectors. The radial nuclear matter density distributions and the root-mean-square nuclear matter radii were deduced from the measured cross sections using the Glauber multiple-scattering theory. A possible neutron halo structure in $^{15}$C, $^{16}$C and $^{17}$C is discussed. The obtained data show evidence for a halo structure in the $^{15}$C nucleus.

This paper discusses the scientific rationale for methods of platinum metals sorption centralization from saturated solutions with a high content of macrocomponents. Methods of sorption centralization of platinum and iridium using local anionites such as AH-31, AB-17-8, Purolite S985 are described. The sorbents used were conditioned to remove organic and mineral impurities. The sorption isotherms of platinum group metals 1/EC=f(1/Cp) at a temperature of 20 °C and a duration of 24 h were plotted. The data on the sorption recovery of platinum and iridium from individual and combined sulfate-chloride solutions were determined. Isotherms of iridium sorption from sulfate-chloride solution are formed. Results of the apparent sorption equilibrium constant and values of standard Gibbs energy (ΔG, kJ/mol) of ion exchange for sorption of platinum and iridium from individual and combined sulfate-chloride solutions are presented. Linearized isotherms and kinetic curves of joint sorption of platinum and iridium from sulfate-chloride solution are described. Comparative sorption of the platinum-group metals (PGM) by anionites AB-17-8 and Purolite S985 from sulfate-chloride solutions is shown. The sorption diagram of platinum and iridium from sulfate-chloride product solutions is presented. It has been revealed that complete recovery is achieved using chelation ion-exchange resin Purolite S985, with recovery of Pt up to 95% and Ir more than 73%. The sorption process is accompanied by intradiffusion constraints that are confirmed by the analysis of kinetic curves using Schmukler and Boyd–Adams models.