Large Diffusion Research Articles

Precipitation governing vegetation patterns in an arid or semi-arid environment.

In an arid or semi-arid environment, precipitation plays a vital role in vegetation growth. Recent researches reveal that the response of vegetation growth to precipitation has a lag effect. To explore the mechanism behind the lag phenomenon, we propose and investigate a water-vegetation model with spatiotemporal nonlocal effects. It is shown that the temporal kernel function does not affect Turing bifurcation. For better understanding the influences of lag effect and nonlocal competition on the vegetation pattern formation, we choose some special kernel functions and obtain some insightful results: (i) Time delay does not trigger the vegetation pattern formation, but can postpone the evolution of vegetation. In addition, in the absence of diffusion, time delay can induce the occurrence of stability switches, while in the presence of diffusion, spatially nonhomogeneous time-periodic solutions may emerge, but there are no stability switches; (ii) The spatial nonlocal interaction may trigger the pattern onset for small diffusion ratio of water and vegetation, and can change the number and size of isolated vegetation patches for large diffusion ratio. (iii) The interaction between time delay and spatial nonlocal competition may induce the emergence of traveling wave patterns, so that the vegetation remains periodic in space, but is oscillating in time. These results demonstrate that precipitation can significantly affect the growth and spatial distribution of vegetation.

Mathematical analysis of the dynamics of some reaction-diffusion models for infectious diseases

We study some reaction-diffusion systems for infectious diseases and investigate how the dynamics is impacted by the movement of populations and spatial heterogeneity of the environment. General conditions for the existence, uniqueness and stability of the coexistence steady states are established. Our analysis revealed two mechanisms for the coexistence of strains: (i) when the ratio of the transmission probability of two strains falls into some intermediate ranges; (ii) when the diffusion rate of two strains falls into proper ranges. Interestingly, when there is no coexistence of strains, it is possible for the “weak” strain to be dominant for some intermediate range of diffusion rates, in strong contrast to small and large diffusion cases where the “weak” strain always goes extinct.

The unexpected magnetism in 2D group-IV-doped GaN for spintronic applications

In this study, we systematically investigated the structural and magnetic properties of group-IV-doped monolayer GaN by first-principles calculations. Among the group-IV element, only Ge and Sn atoms with large atomic radii can form a buckling substituted doping structure with an in-plane magnetic moment of 1 μB per dopant. The compressive strains enhance the in-plane magnetic anisotropy, while tensile strains tend to destroy the magnetic moment of dopants. Both Ge and Sn atoms can stay on the same side of monolayer GaN to form anti-ferromagnetic semiconductors due to the large diffusion barrier for crossing to the monolayer GaN. The intrinsic Ga or N vacancies will eliminate the magnetic moments of group-IV dopants due to the charge transferring from the dopants to intrinsic vacancies. The N-rich growth conditions and a plentiful supply of Ge or Sn dopants to fill the intrinsic vacancies help to maintain the magnetic properties of group-IV-doped monolayer GaN.

Nanostructured Spinel Manganates and Their Composites for Electrochemical Energy Conversion and Storage

AbstractSpinel manganates (AMn2O4; A = Co, Ni, Cu, Zn, and Fe; collectively referred to as AMO) are promising electrode materials for water electrolyzers, pseudocapacitors, and batteries owing to their inherent advantages such as valence variability, high catalytic activity, conductivity, stability, low‐cost, and environmental friendliness. Nanostructured materials, with a large surface area and short ion diffusion length, offer great potential for achieving enhanced electrochemical performance. This review summarizes spinel manganates with various nanostructured morphologies and discusses the impact of the structure and composition on the electrochemical performance. The review demonstrates that nanostructured spinel manganates with preferred A‐site cation significantly improve the thermodynamics and electrochemical reaction kinetics at solid–liquid and solid–solid interfaces. Notably, faceted, hollow, 1D nanostructured CoMn2O4 and its nanocomposites (CoMn/CoMn2O4 and NiMn2O4/C) exhibit outstanding electrochemical performance. The review also provides an overview of the importance of energy conversion and storage, and the advantages of spinel manganates as electrode materials. Additionally, the review describes feasible methods of synthesizing AMO nanostructures and nanocomposites. The insights provided in this review are expected to contribute to the synthesis of spinel manganates with desired morphologies and compositions, enabling the future development of efficient electrode materials for energy conversion and storage devices.

A Deformation–Diffusion-Coupled Constitutive Theory for Hydrogels by Considering the Preparation Conditions

Hydrogels are excellent soft materials that can absorb large amounts of water and have applications ranging from biocompatible sensors to soft robots. Experiments have demonstrated that the equilibrium swelling state of hydrogels strongly depends on their preparation and external conditions, such as the as-prepared water content, cross-linking density, and temperature. However, traditional theories based on Flory’s work have failed to capture these dependence effects. In particular, these theories ignore the existence of solvents in the as-prepared state of hydrogels, making them unable to characterize the sensitivity of the swelling and mechanical behaviors to the as-prepared water content. In this study, we propose a constitutive theory that considers the preparation conditions based on statistical thermodynamics. Our theory can precisely predict the swelling ability of hydrogels under diverse preparation conditions and capture the phase transitions of temperature-sensitive hydrogels. We further derived the governing equations for large deformations and solvent diffusion considering their strong coupling effects. Based on our theory, the inhomogeneous deformation-induced solvent migration and delayed fracture of hydrogels were investigated. From theoretical investigations, we revealed the underlying mechanism of these interesting hydrogel behaviors. The theoretical results were further used to guide the design of diverse intelligent structures that can be applied as soft actuators, flexible robots, and morphing the growth of plants.

Impact of Spatial Memory on a Predator–Prey System with Allee Effect

Recently, spatial memory and Allee effect have been widely investigated in population models, independently. This paper introduces these two aspects to a predator–prey system, and studies the interaction of two species. Allee effect causes bistability, and the predator-free steady-state is always locally stable. Prey-taxis can play a stable role in positive constant steady-state, and spatial memory delay generates the inhomogeneous Hopf bifurcation and even stability switching. In the absence of spatial memory delay, the stronger the predator is subject to the Allee effect, the larger the prey-taxis coefficient is required to keep two species coexist in a stable spatially homogenous form. With the same prey-taxis coefficient, the critical threshold of spatial memory delay corresponding to large predator diffusion coefficient is distinctly bigger than the one corresponding to small predator diffusion coefficient. Moreover, the amplitudes of spatial patterns, which reflect the degree of inhomogeneity, oscillate as spatial memory delay varies.

Vacuum diffusion bonding between equiatomic CoCrNi-based concentrated solid solution alloys system and 316 stainless steel by spark plasma sintering

Spark plasma sintering (SPS) is a new method for diffusion bonding of dissimilar metals. In this study, equiatomic CoCrNi-based concentrated solid solution alloys (CSSAs) system (CoCrFeNiMn, CoCrFeNi, and CoCrNi) were successfully joined to 316 stainless steels by SPS diffusion bonding, and the effect of bonding temperature and concentration on diffusion behavior and tensile property of bonded joints were investigated. The tensile strength of the CSSAs/316SS joints were gradually increased with increasing bonding temperature. In addition, the tensile strength of the joints bonded at 0.8Tm were all exceeded 80% of that in 316SS. Meanwhile, the bonding at 0.8Tm seemed to have sufficient diffusion and grain growth at the interface, resulted in the disappearance of voids and the increase in strength of joint. In CoCrNi/316SS joint, large element concentration variation would amplitude in the diffusion zone, could result in rapid diffusion of atoms and large diffusion distance. The diffusion distance of diffusion zone in the CoCrNi/SS joint was increased by nearly two times compared to traditional diffusion bonding. Furthermore, it suggests that the continuous FCC solid solution structure was generated in the diffusion zone, which was beneficial to the increase of tensile property in joints. The tensile strength and elongation of diffusion bonded CSSAs/316SS joints were increased compared to laser beam welded joints.

Anomalous Dependence of Translational Diffusion on the Water Mole Fraction for Solute Molecules Dissolved in a 1-Butyl-3-methylimidazolium Tetrafluoroborate/Water Mixture.

Translational diffusion coefficients of carbon monoxide (CO), diphenylacetylene (DPA), and diphenylcyclopropenone (DPCP) were determined in mixtures of 1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim]BF4) and water using transient grating spectroscopy at different mole fractions of water (xw). While DPA exhibited a larger diffusion coefficient than DPCP at low water mole fractions (xw < 0.7), as observed for conventional liquids and ionic liquids (ILs), it was smaller at high mole fractions (xw > 0.9). The apparent molecular radius of DPA determined using the Stokes-Einstein equation at xw > 0.9 is close to the radius of an IL cluster in a water pool as determined from small-angle neutron scattering experiments (J. Bowers et al., Langmuir, 2004, 20, 2192-2198), suggesting that the DPA molecules are trapped in IL clusters in the water pool and move together. The solvation state of DPCP in the mixture was studied using Raman spectroscopy. Dramatically strong water/DPCP hydrogen bonding was observed at higher water mole fractions, suggesting that DPCP is located near the cluster interfaces. The large diffusion coefficient of DPCP suggests that hopping of DPCP between IL clusters occurs through hydrogen bonding with water.

Na3V2O2(PO4)2F nanoparticles@reduced graphene oxide: a high-voltage polyanionic cathode with enhanced reaction kinetics for aqueous zinc-ion batteries

Na3V2O2(PO4)2F is characterized by a high theoretical specific capacity, high-voltage plateaus, large ion diffusion channels, and stable three-dimensional structure, which is a promising cathode candidate for rechargeable aqueous zinc-ion batteries (AZIBs). Nevertheless, the low electronic conductivity hinders its cycling and rate performance. In this work, a facile microwave-assisted solvothermal approach with postheat treatment has successfully produced Na3V2O2(PO4)2F nanoparticles with the dimension of 20–50 nm wrapped by reduced graphene oxide (rGO). The high pseudocapacitive contribution, high diffusion coefficient, low electrochemical impedance, favorable electrode wettability, and stable structure can be obtained by optimizing the chemical components of electrolyte and the content of rGO, facilitating the Zn2+ storage performance. Hence, Na3V2O2(PO4)2F@rGO delivers excellent electrochemical properties such as a high capacity of 127.0 mAh g−1 at 0.5C, a stable capacity of 63.9 mAh g−1 at 30C after 5000 cycles, and a high average voltage plateau of 1.50 V in hybrid aqueous electrolyte (2 M zinc trifluoromethane sulfonate (Zn(OTf)2) and 4 M lithium trifluoromethane sulfonate (LiOTf)). Furthermore, exceptional cycling performance in the soft-pack batteries with the size of 3 × 3.5 cm2 includes a reversible capacity of 84.1 mAh g−1 at 10C after 1000 cycles. In situ X-ray diffraction, ex situ X-ray photoelectron spectroscopy, transmission electron microscopy, and scanning electron microscopy reveal reversible Zn2+ insertion/extraction process.

Research Progress on the Synthesis of Nanosized and Hierarchical Beta Zeolites

Beta zeolite, a crystal material with a three-dimensional twelve-ring cross-channel structure, has many advantages, such as high Brønsted acid concentration, high Si/Al ratio, thermal/hydrothermal stability, and large surface area. Due to these advantages, beta zeolite shows excellent catalytic performance in petroleum refining and petrochemical processes. However, traditionally microporous beta zeolite has strong steric hindrance and diffusion restrictions, which hinder large molecules from passing through its internal channels. In addition, carbon deposition occurs, resulting in catalyst deactivation. The main strategy to solve this problem is to prepare nanosized or hierarchical beta zeolites, which allow for large molecule conversion and shortening diffusion pathways. Therefore, researchers have explored different synthesis strategies to prepare beta zeolite with different particle sizes and porosities to obtain better zeolite catalysts. This paper briefly describes the recent research progress in the preparation of nanosized and hierarchical beta zeolite. Additionally, the mechanisms of various preparation methods, structural characteristics, and applications of the materials are introduced in detail. Furthermore, the main problems existing in its industrial application are describing by comparing the advantages and disadvantages of the different methods to prepare optimally nanosized and hierarchical zeolite to meet the requirements of industrial development.

Effects of diffusion and advection on predator-prey dynamics in closed environments

We investigate the dynamics and the asymptotic profiles of positive steady states of a specialist predator-prey model and a generalist predator-prey model in closed advective environments. The threshold dynamics are determined by the mortality rate of the specialist predators and the predation rate of the generalist predators, respectively. We demonstrate that, no matter how large advection and diffusion rates are, the specialist predators can successfully invade as long as the mortality rate is sufficiently small, while the generalist predators can take-over the prey if the predation rate is relatively large. Finally, we explore the impacts of diffusion and advection on the asymptotic profiles of positive steady states. Our results imply that large advection rates and small diffusion rates will lead to the concentration of the species at the downstream or the upstream. Moreover, if the diffusion rates are large, then the densities of the species will be less spatial heterogeneous.

Analysis of a diffusive host–pathogen epidemic model with two‐stage mechanism in a spatially heterogeneous environment

Due to the spatial heterogeneity present in many aspects of disease transmission, the rate of transmission of infectious diseases, human birth/mortality rate, and the mobility ability of infected humans should be different in different geographical locations. On the other hand, infected humans may exhibit distinct differences in symptoms during the different stages of the disease transmission. This paper aims to study threshold dynamics of a reaction–diffusion host–pathogen model governed by two‐stage mechanism and no flux boundary condition. In the model, we use bilinear and saturated incidence mechanism to model the interactions between host populations and pathogens and assume that (i) the parameters are spatially dependent and (ii) infected individuals in the first stage can random walk, while in the second stage, the diffusion rates are neglected. By carrying out strict analysis, the paper establishes the threshold‐type results with the basic reproduction number. Specifically, in a homogeneous case that all parameters are constants, we establish the global attractivity of the endemic equilibrium. To investigate the effects of small or large diffusion rates of susceptible individuals on the disease transmission in a heterogeneous environment, we explore the asymptotic profile of positive steady state whenever it exists. Our numerical results validate the theoretical results and indicate the importance of the infected humans in the second stage and pathogens in the environment in disease transmission, which greatly contribute to disease spread in a bounded domain and should not be ignored.

Two-dimensional VSe2/CNT functional materials boosted polysulfide conversion for high stability lithium-sulfur battery

Lithium-sulfur batteries are considered one of the most likely next-generation batteries to be commercialized because of their high theoretical energy density, but severe shuttle effects affect their practical application. Herein, two-dimensional layered vanadium diselenide is combined with carbon nanotubes (2D-VSe2/CNT) to act as advanced sulfur host to suppress the shuttling of lithium polysulfides. 2D-VSe2/CNT possesses sulfiphilic surface and high electrical conductivity, which is beneficial for chemisorption of polysulfides as well as the nucleation and growth of Li2S. In addition, the fast kinetic response is confirmed by the higher current density and the large lithium ion diffusion coefficient. Furthermore, VSe2/CNT/S cathode shows ultra-stable cycling performance with a capacity decay rate of only 0.03% after 500 cycle at 0.5C.

Detonation peninsula of different stoichiometric ammonia/hydrogen/air mixtures under engine-relevant conditions

This study numerically investigates the detonation development of carbon-free fuels, namely ammonia and hydrogen (NH3 and H2), using one-dimensional (1D) simulations under the end-gas autoignitive conditions relevant to internal combustion (IC) engines. Five stoichiometric NH3/H2/air mixtures with different NH3/H2 blending ratios are studied. A 1D hot spot with varied lengths and temperature gradients is used to induce different ignition modes. The detonation peninsulas are quantitatively identified by two non-dimensional parameters, namely the resonance parameter, ξ, and the reactivity parameter, ε. Increasing the H2 blending ratio up to 80% results in a unique horn-shaped detonation peninsula, i.e., the magnitude of the upper and lower ξ limits, ξu,l, near the leftmost boundaries of the detonation peninsula of the rich-H2 mixtures becomes larger by an order of magnitude as compared to those of the lean-H2 mixtures. Such behavior is attributed primarily to the large heat diffusion of hydrogen, leading to rapid heat dissipation of the hot spot and the significantly decreased transient ξ over time, thus promoting detonation development. The analysis reveals that the characterization of detonation propensity in the rich-H2 mixtures needs to account for the fast heat diffusion of the initial hot spot, in which the initial magnitude of ξ is not representative of its detonability. As such, a correction factor, β, weighted by the ignition Damköhler number, is proposed to resolve the discrepancy of the ξu,l limits between different NH3/H2/air mixtures. With this correction, the transient magnitudes of ξ, ξt, prior to the main ignition are well predicted such that a unified shape of the detonation peninsula for different NH3/H2/air mixture compositions is achieved.

Experimental measurements of the moisture diffusion and strength damage mechanism of dense asphalt mixtures

ABSTRACT Moisture migration in pavement leads to the loss of strength of asphalt mixture. However, moisture profile measurement inside of the mixture can be challenging. In this paper, a new experimental method is proposed to measure the moisture profile; this method is based on the principle that white anhydrous copper sulfate powder turns blue with water. The influences of asphalt content, gradation, indoor compaction, temperature and pressure on moisture diffusion depth and strength loss are also discussed. The results show that the proposed method successfully reveals the moisture profile of the asphalt mixture. High temperature and pressure accelerate the moisture diffusion process. A large filler-bitumen ratio and high content of coarse aggregate result in a large diffusion depth. The rolling compacted mixture demonstrates better resistance to moisture diffusion than the Marshall mixture. It is inferred that the rainfall’s influence on the asphalt layer is mainly within a depth of 23 mm below the surface. The strength attenuation of asphalt mixture after damage is mainly affected by compaction method and external pressure, while filler-bitumen ratio affects the attenuation trend of the mixture strength. The proposed method in this paper has the advantages of easy operation and in-field application potential.

PH-depended behaviors of electrolytes in nanofluidic salinity gradient energy harvesting

Transmembrane ion transportation in the nanofluidic salinity gradient energy conversion process is significantly regulated by the ion characteristics and concentration-depended physical and chemical properties of the electrolyte solution. In this paper, considering the Born and dielectrophoretic forces and nonhomogeneous electrolyte solution, impacts of various electrolytes on the nanofluidic energy conversion performance are systematically investigated under various solution pHs. When the solution pH is less than the isoelectric point (IEP), with BeCl2 solution employed, where the anion diffusion and concentration coefficient are much larger than those of the anion, significant transmembrane anion diffusion exists, leading to the highest osmotic current and maximum power output, even when the solution pH > IEP where the nanochannel is negatively charged, the ion selectivity is still not altered. At pH < IEP, 2:1 electrolytes, where the cation has small ion diffusion coefficient and the anion has larger diffusion coefficient and hydrated radius could result in upgraded energy conversion performance; At pH > IEP, 1:1 electrolytes where the cation has large ion diffusion coefficient and the anion has small diffusion coefficient and large hydrated radius are more appealing. In addition, the relationships between ion characteristics, power extracted, and energy conversion efficiency are further obtained via machine learning.

Large Diffusion of Severe Acute Respiratory Syndrome Coronavirus 2 After the Successive Epidemiological Waves, Including Omicron, in Guinea and Cameroon: Implications for Vaccine Strategies.

We aimed to estimate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence among the general population in Conakry, Guinea and Yaounde, Cameroon after the coronavirus disease 2019 Omicron wave. We conducted population-based, age-stratified seroprevalence surveys in Conakry and Yaounde (May and June 2022). We collected demographic and epidemiologic information and dried blood spot samples that were tested for SARS-CoV-2 immunoglobulin G (IgG) antibodies using recombinant nucleocapsid and spike proteins with Luminex technology. Samples were obtained from 1386 and 1425 participants in Guinea and Cameroon, respectively. The overall age-standardized SARS-CoV-2 IgG seroprevalence against spike and nucleocapsid proteins was 71.57% (95% confidence interval [CI], 67.48%-75.33%) in Guinea and 74.71% (95% CI, 71.99%-77.25%) in Cameroon. Seroprevalence increased significantly with age categories. Female participants were more likely than male participants to be seropositive. The seroprevalence in unvaccinated participants was 69.6% (95% CI, 65.5%-73.41%) in Guinea and 74.8% (95% CI, 72.04%-77.38%) in Cameroon. In multivariate analysis, only age, sex, and education were independently associated with seropositivity. These findings show a high community transmission after the different epidemiological waves including Omicron, especially among people aged >40 years. In addition, our results suggest that the spread of SARS-CoV-2 has been underestimated as a significant proportion of the population has already contracted the virus and that vaccine strategies should focus on vulnerable populations.

On Urgently Tackling the Mosquito-Borne Diseases in the European Union

Context: According to a recent Lancet report the world is dangerously close to reaching climate-driven points of no return. Climate change, together with other drivers, contributed to a large diffusion of mosquito-borne diseases (MBDs) in the last decades. The intensity of such a phenomenon led various mosquito species to migrate to new areas, outside their historical habitats. Europe is among the affected territories. Moreover, the problem is projected to rise and expand within the continent, including populations who have never been exposed to MBDs and impacting the whole society, especially the most vulnerable groups. As Europe is a relatively new area for the diffusion of MBDs, no strong and unified measures have been put into practice yet. Meanwhile, MBDs surveillance experiences implemented across Europe report gaps, such as the absence of entomological research and legal support, the capacity limitation for surveillance, and variability in entomological and epidemiological surveillance systems. Hence, it could be necessary to use the experiences from Latin America, Asia and Africa. Given the aforementioned overview, this policy brief aims to provide policy options in order for the European Union to address MBDs, with a particular emphasis on strengthening surveillance across the Member. States given recent attention drawn to this issue by the ECDC’s 2021 report on vector control and surveillance. Policy Options and recommendations: This advisory group conducted a non-systematic literature review to determine three policy options, with a specific focus on surveillance, to address the issue of MBDs. 1. Surveillance systems for mosquitoes and MBDs should be implemented in all member states, and case definitions for these MBDs should be harmonised to enable coordination and consistency of MBDs surveillance across the European Union (EU). 2. Create an EU-level networks umbrella for financial and organisational coordination of Member States (MS)’ multi-sectoral collaboration on MBDs surveillance. 3. Developing the competencies for surveillance and research professionals for mosquitoes and MBDs surveillance.

Chitosan-based hollow nanofiber membranes with polyvinylpyrrolidone and polyvinyl alcohol for efficient removal and filtration of organic dyes and heavy metals

Due to their large specific surface area and numerous diffusion channels, hollow fibers are widely used in wastewater treatment. In this study, we successfully synthesized a chitosan (CS)/polyvinylpyrrolidone (PVP)/polyvinyl alcohol (PVA) hollow nanofiber membrane (CS/PVP/PVA-HNM) via coaxial electrospinning. This membrane demonstrated remarkable permeability and adsorption separation. Specifically, the CS/PVP/PVA-HNM had a pure water permeability of 4367.02 L·m−2·h−1·bar−1. The hollow electrospun nanofibrous membrane exhibited a continuous interlaced nanofibrous framework structure with the extraordinary advantages of high porosity and high permeability. The rejection ratios of CS/PVP/PVA-HNM for Cu2+, Ni2+, Cd2+, Pb2+, malachite green (MG), methylene blue (MB) and crystal violet (CV) were 96.91 %, 95.29 %, 87.50 %, 85.13 %, 88.21 %, 83.91 % and 71.99 %, and the maximum adsorption capacities were 106.72, 97.46, 88.10, 87.81, 53.45, 41.43, and 30.97 mg·g−1, respectively. This work demonstrates a strategy for the synthesis of hollow nanofibers, which provides a novel concept for the design and fabrication of highly efficient adsorption and separation membranes.

STRESS-DEFORMED STATE OF VERTICAL CILINDRICAL METAL SHELL UNDER TEMPERATURE CLIMATE IMPACT

Vertical cylindrical containers are widely used for storage of granular bulk materials. The enclosing side surface of such containers is made in the form of cylindrical metal circular shells with a wall thickness that is constant or piecewise constant along the height of the shell. Known designs for storage of bulk materials of the reservoir type with the installation of a cylindrical shell on the annular foundation with hinged fixed attachment of the shell to the foundation. Thin-walled shells are made suspended from the supporting structures of the storage facilities. To stabilize the cylindrical shape of the shell and its position in space, the suspended shells are pre-tensioned in the vertical direction. During operation, storage facilities are empty and filled with bulk materials, exposed to the environment in the form of wind and temperature climatic influences. The object of study of this work is the enclosing structures of storages of granular bulk materials in the form of vertical circular cylindrical thin-walled metal shells, in the general case of piecewise constant thickness, subject to temperature and climatic influences of the environment ‒ changes in the temperature of the outside air, direct and diffuse solar radiation. The subject of the study is the components of the stress-strain state of the shell due to changes in temperature and climatic influences. The performed studies of the temperature fields of storage shells on models and full-scale objects made it possible to substantiate the assignment of the temperature field of cylindrical storage shells by Fourier series. One-sided solar heating of cylindrical storage shells completely illuminated by the sun induces in the shell wall a flat temperature field symmetrical with respect to the normal of incidence of sunlight, which can be represented by a Fourier series with five terms of the cosine expansion series. In the presence of a structure located next to the shell, which covers half of the shell along the entire height in the circumferential direction, the temperature field is described by a Fourier series containing 10 harmonics of expansion in sines and cosines. The small thickness of the shell, the significant radius of curvature of the shells, the large thermal diffusivity of metals provides a small variability of the temperature of the shell over the thickness, the ability to describe the stress-strain state of the shell, the momentless theory and a simple edge effect. Formulas are obtained in Fourier series for the forces of a momentless state, the residuals of which at the joints of shell chords of different thicknesses and in the support zones are eliminated by a simple edge effect.