Water Transport Research Articles

Changes in Cx43 and AQP4 Proteins, and the Capture of 3 kDa Dextran in Subpial Astrocytes of the Rat Medial Prefrontal Cortex after Both Sham Surgery and Sciatic Nerve Injury.

A subpopulation of astrocytes on the brain's surface, known as subpial astrocytes, constitutes the "glia limitans superficialis" (GLS), which is an interface between the brain parenchyma and the cerebrospinal fluid (CSF) in the subpial space. Changes in connexin-43 (Cx43) and aquaporin-4 (AQP4) proteins in subpial astrocytes were examined in the medial prefrontal cortex at postoperative day 1, 3, 7, 14, and 21 after sham operation and sciatic nerve compression (SNC). In addition, we tested the altered uptake of TRITC-conjugated 3 kDa dextran by reactive subpial astrocytes. Cellular immunofluorescence (IF) detection and image analysis were used to examine changes in Cx43 and AQP4 protein levels, as well as TRITC-conjugated 3 kDa dextran, in subpial astrocytes. The intensity of Cx43-IF was significantly increased, but AQP4-IF decreased in subpial astrocytes of sham- and SNC-operated rats during all survival periods compared to naïve controls. Similarly, the uptake of 3 kDa dextran in the GLS was reduced following both sham and SNC operations. The results suggest that both sciatic nerve injury and peripheral tissue injury alone can induce changes in subpial astrocytes related to the spread of their reactivity across the cortical surface mediated by increased amounts of gap junctions. At the same time, water transport and solute uptake were impaired in subpial astrocytes.

Investigation into transport behavior of platinum‐Nafion interface with functionalized graphene oxide

AbstractIn the catalytic layer of proton exchange membrane fuel cells, water molecules in ionomers tend to be accumulated at the ionomer/Pt interface, preventing oxygen from reaching the Pt surface to participate in chemical reactions. It is necessary to take measures to improve the water molecules distribution and proton transport performance in the ionomer on the Pt surface. In this work, the effect of “acid–base pair” functionalized graphene oxide (AB‐GO) as the additive on the distribution of water molecules and transport property in the ionomer is evaluated. The results demonstrate that with the addition of AB‐GO, the distribution uniformity of water molecules and hydronium ions in the ionomer on the Pt surface is improved. The connectivity of water cluster is also increased. When the doping ratio of BAF‐GO and TF‐GO is 1:3, the connectivity coefficient of water cluster is about 1.37 times that of Nafion ionomer without the doping.

Monitoring the Impact of Artificial Structure on Hydrogeological Environment: A Case Study of Hydraulic Tunnel at Pirot Hydropower Plant.

Artificial objects, particularly tunnels used for water transport under pressure, impact the geological and hydrogeological environment to a greater or lesser extent, and it is vital to assess their contributions to groundwater quality. Although tunnels are typically lined with concrete, their interaction with the hydrogeological environment intensifies over time. In this study, the detailed spatiotemporal monitoring of all hydrogeological features within the potential influence zone of the hydraulic tunnel of the Pirot Hydropower Plant has been conducted in order to determine the degree of interaction between the artificial object and the natural environment in real time, and to assess the correlation between monitored parameters. Natural conditions of the environment were defined, as well as potential changes through the observing groundwater regimes. The monitoring network included observations of groundwater regimes at seven springs located in close proximity to the hydraulic tunnel, within the tunnel, at three piezometers, and along the river, while methods employed were hydrological monitoring, physicochemical monitoring, and groundwater piezometer sensing. Cross-correlation analysis has been applied for assessing the impact of precipitation dynamics on the spring discharge regime. The results indicate a direct influence of the tunnel on the hydrogeological environment, proving the consistency and high correlation between the monitored parameters.

Penambahan Media Kapas Dan Kerikil Pada Multi Tray Aerator Untuk Pengolahan Air Daerah Rususnawa Untan Dalam Mengurangi Kandungan Logam Sebagai Pre-treatment Pada Sistem Membran RO

Rivers are surface water used for public purposes. Rivers are used for water storage, transportation, irrigation, livestock, industry, housing, water availability, fish rearing and recreation. Various activities carried out in the river cause pollution and have an impact on the decline in water quality, such as in Sepakat 2 river water which is used by the surrounding community for daily needs. The purpose of this study was to determine the Fe contained in Sepakat 2 river water and the effectiveness of using multi tray aerators with the addition of cotton and gravel media in reducing iron levels. Processing of Sepakat 2 river water through a pretreatment process using a 5-level multi tray aerator method and 6 perforated trays to drop water to the bottom of the container, then the water that has been aerated is collected in a box and deposited for 1 and 2 hours after which the water is taken and stored using a bottle container to be analyzed by the Pontianak Industrial Standardization and Services Center Laboratory. The results of this study are the quality of river water Sepakat 2 iron levels 6.37 mg / L before processing, after aeration 4.99 mg / L, after settling 1 and 2 hours with the same value of 5.09 mg / L. The efficiency of the multi tray aerator tool to reduce iron parameters from iron by 20.09%, TDS 52.1%, mercury (Hg) 43.08% and salinity is 63.3%.

Sustainable mega-seaports with integrated multi-energy systems: Life-cycle environmental and economic evaluation

Ports play a critical role in modern society by acting as crucial links between water and land transportation, and integrating transportation with energy systems. This integration results in a high demand for various types of energy uses, with polluting emissions produced by the diverse energy sources. Integrated renewable energy systems represent promising solutions to achieving high levels of energy supply while lowering carbon footprints. In this research, a framework is proposed for a port multi-energy system that encompasses solar energy, wind energy, a hydrogen system and a number of energy storage systems. The proposed framework is tailored for implementation at Ningbo Zhoushan Port, the largest port globally. Different system design schemes are compared based on the number and rated power of wind turbines. Then, a comprehensive life-cycle economic and environmental assessment of the system is conducted through simulation. The economic and environmental metrics such as LCOE, REF and CO2 emissions are considered. The outcomes demonstrate that the design scheme incorporating two wind turbines with high rated power outperforms others in both environmental and economic metrics. Over the life-cycle, the renewable energy fraction exceeds 72%, and the levelized cost of energy plummets to 0.46 yuan/kWh. The implementation of the proposed port integrated multi-energy system yields substantial environmental and economic benefits. Specifically, it allows for a reduction of 66.68% in CO2 emissions and a cost reduction of 70.94%. These outcomes highlight the potential that the proposed system holds for enhancing environmental sustainability and economic efficiency within the port context.

First Report of Ralstonia pseudosolanacearum Causing Bacterial Wilt in Ginger in Peru.

Around 90% of Peru's ginger (Zingiber officinale) production is concentrated in the Junín region, due to the optimal agroecological conditions for its cultivation. In March 2024, fields with ginger plants (cultivar Criollo) in Junín region, provinces Chanchamayo and Satipo, specifically in the cities of Pichanaqui and Satipo respectively, exhibited approximately 40% of plants with severe symptoms of a disease characterized initially by plant yellowing and rapid progressing to necrosis. Affected rhizomes showed dark vascular bundles with milky white exudates upon cutting, while stems displayed vascular necrosis hindering water and nutrient transport, often resulting in plant death. Fifteen plants were sampled and diseased vascular tissues from rhizomes and stems were cultured on nutrient agar (NA) and incubated at 28°C. After 72 h, all isolations resulted in colonies with typical characteristics of Ralstonia solanacearum species complex (RSSC) were produced, with appearing fluid, irregularly round, and creamy white. Three isolates were selected for the identification steps (UNALM-RP01 to 03) were identified by PCR using primers 759/760 (Opina et al. 1997) confirming as RSSC with a 282 bp amplification product. Additionally, isolates were assigned to biovar 3 based on their ability to metabolize three acid-producing disaccharides (maltose, lactose, cellobiose) and three hexose alcohols (mannitol, sorbitol, dulcitol) (Hayward, 1964). Phylotype I was identified by multiplex PCR (primers Nmult) with a 114 bp amplification product (Fegan and Prior 2005). For the identification of the sequevars of the three isolates, DNA was extracted and PCR with primers ENDO-F/R (Ji et al. 2007) were performed to amplify and sequence the partial gene sequence of egl gene with 681 bp in length. The phylogeny by Neighbor joining with 10,000 bootstraps clustered the UNALM isolates along other sequevar 30 of R. pseudosolanacearum. The sequences were deposited in Genbank under accessions PQ213016, PQ213017 and PQ213018. For pathogenicity tests, bacterial colonies of isolate UNALM-RP01 were scraped from the culture media with a sterile needle and introduced into the stems of three 2-month-old ginger plants (cultivar Gigante). The plants subsequently exhibited yellowing seven days post-inoculation. Additionally, the rhizomes showed internal discoloration and bacterial exudation. Three plants were used as a control, which were pierced with a sterilized needle and showed no symptoms. All tested plants were kept in a greenhouse with controlled temperature (20-40 °C) The pathogen was successfully re-isolated from infected plants on NA medium, presenting typical colonies of RSSC and identified via PCR with primers 759/760, fulfilling Koch's postulates. This represents the first case in Peru of ginger plants infected with a Ralstonia species, specifically R. solanacearum phylotype I, corresponding to R. pseudosolanacearum. This species of RSSC and sequevar is known for causing disease in ginger. Its presence in Peru, however, may be the result of the pathogen's introduction, as its geographical origin is associated with Asia (Fegan and Prior 2005). To our knowledge, this is the first report of R. pseudosolanacearum causing ginger wilt disease in Peru. In 2024, an estimated average yield loss of 30% has been attributed to wilt disease in the Junín region, posing a significant threat to cultivation. Urgent and effective disease management strategies are essential to control and mitigate further losses.

A novel mechanistic model for predicting shrinkage kinetics in plant-based foods by integrating solid matrix mobility and viscoelasticity

Deformation during drying is a major physical change influencing drying kinetics and final product quality. Therefore, accurate prediction of shrinkage kinetics is essential for determining the optimal drying conditions for these foods. Shrinkage kinetics is greatly influenced by their structural mobility (rubbery-glassy transition) and viscoelastic properties. The current deformation models lack a comprehensive integration of structural mobility and viscoelasticity concepts, resulting in limitation in attaining insights on physiochemical state variations and viscoelastic stresses developed during drying. In order to overcome this limitation, this study proposes a novel mechanistic shrinkage model that combines solid matrix mobility-based shrinkage velocity and viscoelasticity consideration, incorporating variable mechanical properties to simulate deformation arising from moisture loss and pressure gradient respectively. Comparison between predicted drying kinetics and shrinkage evolution with experimental observation yielded close agreement, achieving low mean absolute error values. As the drying process progressed, a distinct anisotropic shrinkage pattern emerged, which is attributed to varied structural mobility based on temperature and moisture distribution across the food sample. Notably, shrinkage driven by moisture loss significantly outweighed that induced by pressure, exerting a predominant influence on overall volume change. Furthermore, the model demonstrated heightened sensitivity to water transport parameters compared to mechanical factors, which indicates the significance of moisture dynamics in shaping the drying process. Combined consideration of physiochemical changes and viscoelastic concept in the developed deformation model extends new possibility towards optimizing the drying process as well as quality aspect evaluation.

Enhancing Functionality and Minimizing Damage of Air Valves in Pipelines Using FRP Sheets

Pipelines play a vital role in ensuring the efficient and secure transportation of water, making their performance to keep the water continuously going vital. This research explores the influence of air valves on the localized damage and overall functionality of the pipelines. Air valves are critical components that help stabilize pressure and prevent vacuum formation. However, their installation can introduce structural weaknesses in localized areas. The study employs FEM modeling alongside field data from a collapsed bridge to assess the performance and damage in the vicinity of air valves. The findings reveal that strategic redesigns, such as optimizing air valve placement and reinforcing surrounding areas, can significantly enhance performance while mitigating local damage. Additionally, the research highlights the effectiveness of repair methods in increasing pipeline resistance to bending stresses and compares various repair and design approaches, providing new insights into mitigating structural damage in aqueduct bridges. This study addresses a critical gap in the literature, offering a thorough approach to understanding and addressing air valve-related damage in engineering.

The importance of source data in river network connectivity modeling: A review

AbstractRiver network connectivity (RC) describes the hydrologic exchange of water, nutrients, sediments, and pollutants between the river channel and other “sites” via heterogenous flowpaths along the river corridor. As water moves downstream it carries these constituents, creating a stream‐to‐ocean continuum of connectivity that regulates global water, carbon, and nutrient cycling. River network connectivity models have developed over many decades, culminating in recent years with network‐scale RC models that explicitly simulate the transport and exchange of water and elements from headwaters to coasts, sometimes requiring models to contain tens of millions of river reaches. These advances provide transformative insights into the aggregate effects of RC on water and material transport across scales from local to global. Yet, recent reviews have pointed to several challenges that need to be overcome to continue advancing network‐scale RC modeling. In service of these goals, I summarize recent network‐scale RC maps and models to identify similarities and differences across the large‐scale RC modeling landscape. Although our computational and upscaling abilities have significantly improved and have revealed new insights, current models are still limited by the quantity, quality, resolution, and lack of standardization of the available in situ databases and source data maps necessary for the modeling. This suggests that we can extend recent advances if we keep improving these source datasets, while continuously revisiting our physics and theory to explain those new data. In doing so, we will continue to expand the role of network‐scale RC models in informing water quality modeling and management into the future.

Automatic Image Analysis Method as a Tool to Evaluate the Anisotropy of Autoclaved Aerated Concrete for Moisture and Heat Transport

In this article, the results of studies testing the anisotropy of autoclaved aerated concrete in terms of water and heat transport are presented. Using image analysis techniques, a study was conducted on four different samples of concrete produced in the same process. To ensure the comparability of results, the pictures were taken from a fixed distance with the same lens settings trimmed to a set size. Cross-sectional profiles of the material were examined and were arranged in two directions: perpendicular and parallel to the growth direction occurring in the autoclave. For each block, approximately 4750 objects were obtained, with an average of 2700 objects along the wall and 2050 across it. As a result of the comparative analysis, metrics concerning pores, significantly distinguishing the profile direction, were identified. These included the pore area (area), the maximum and minimum distance between points on the perimeter (Feret, MinFeret), lengths of the major and minor axes of the fitted ellipse (major, minor), and the ratio of the area of selection to its convex hull (solidity). As a reference, standard investigations were conducted for moisture transport using the time domain reflectometry setup and for thermal conductivity values using the steady-state heat flow plate apparatus.

Unlocking High Capacity and Reversible Alkaline Iron Redox Using Silicate-Sodium Hydroxide Hybrid Electrolytes.

Alkaline iron (Fe) batteries are attractive due to the high abundance, low cost, and multiple valent states of Fe but show limited columbic efficiency and storage capacity when forming electrochemically inert Fe3O4 on discharging and parasitic H2 on charging. Herein, sodium silicate is found to promote Fe(OH)2/FeOOH against Fe(OH)2/Fe3O4 conversions. Electrochemical experiments, operando X-ray characterization, and atomistic simulations reveal that improved Fe(OH)2/FeOOH conversion originates from (i) strong interaction between sodium silicate and iron oxide and (ii) silicate-induced strengthening of hydrogen-bond networks in electrolytes that inhibits water transport. Furthermore, the silicate additive suppresses hydrogen evolution by impairing energetics of water dissociation and hydroxyl de-sorption on iron surfaces. This new silicate-assisted redox chemistry mitigates H2 and Fe3O4 formation, improving storage capacity (199 mAh g-1 in half-cells) and coulombic efficiency (94 % after 400 full-cell cycles), paving a path to realizing green battery systems built from earth-abundant materials.

Rice homolog of Arabidopsis Xylem NAC domain 1 (OsXND1), a NAC transcription factor regulates drought stress responsive root system architecture in indica rice.

Rice yield is greatly constrained by drought stress. In Arabidopsis, XYLEM NAC DOMAIN 1 (XND1) gene regulates the xylem formation, efficiency of water transport, and the delicate equilibrium between drought tolerance and resistance to pathogens. However, diversity and the role of rice homologs of OsXND1 is not reported so far. This study hypothesized that the rice homolog of OsXND1 also regulates drought stress tolerance through modulation of root architecture. Initially, phylogenetic analysis identified two OsXND1 homologs (Os02g0555300 and Os04g0437000) in rice. Further, 14 haplotypes were identified in the OsXND1 of which Hap1 and Hap3 were major haplotypes. The association analysis of OsXND1 with 16 different traits, including 10 root traits, showed three SNPs (Chr02:20972728-Promoter variant; Chr02:20972791-5' UTR variant, and Chr02:20973745-3' UTR variant) were significantly associated with root area, root surface area, total root length, and convex hull area only under drought stress in indica rice. Besides, the superior haplotype of OsXND1 increased the root area, root surface area, total root length, and convex hull area by 46%, 40%, 38%, and 42%, respectively, under drought stress conditions. Therefore, the identified superior haplotype of OsXND1 can be utilized in haplotype breeding programs for the improvement of drought tolerance in rice.

Bifunctional Photothermal Evaporator Based on an MXene/Fe-MOF Collaborative Effect toward Efficient Solar Steam Generation and Simultaneous VOC Removal.

Solar-driven interfacial water evaporation has become one of the most promising approaches to effectively harvesting freshwater, yet the fabrication of high-performance and multifunctional solar interfacial evaporators (SIEs) still remains a huge challenge to date. In this study, a multifunctional MXene and Fe-MOF@cellulose acetate/polyvinylpyrrolidone (MXM@CP) SIE was prepared via a facile "electrospinning and suction filtration deposition" coupling strategy. Thanks to the incorporation of MXene, MXM@CP displayed excellent photothermal conversion performance. Together with the fast water transport channel provided by the porous cellulose acetate electrospinning substrate, a remarkable solar-driven water evaporation property was achieved for MXM@CP, showing a higher water evaporation rate of 1.1 kg m-2 h-1 under one sun irradiation. Moreover, the resultant composite film also exhibited excellent Fenton catalytic activity to effectively degrade volatile organic compounds (VOCs) due to the synergistic effect of the MXene and Fe-based MOF (Fe-MOF). Particularly, a relatively higher degradation rate of 82.8% was acquired for the resulting evaporator toward the benzene contaminant. These results provide new insights into the construction of high-performance and multifunctional SIEs toward clean freshwater collection from the VOC-contaminated water system.

Constructing multi-path channels in graphene oxide-based membrane for high-efficiency oil/water separation

Graphene oxide (GO) membranes have demonstrated significant potential for effective wastewater treatment; however, their tortuous and irregular water transport pathways through stacked nanosheets pose considerable challenges. In this study, we present a novel approach for fabricating faveolate-structured graphene oxide nanomesh (GONM) membranes, enhanced by the in situ growth of Co(OH)2 nanosheets to facilitate oil–water separation. The incorporation of in-plane pathways through the porous GONM, alongside the enlargement of interlayer pathways from Co(OH)2 growth, significantly improves water permeance. The nanopores present in the holey GONM reduce diffusion pathways, while intercalation of Co(OH)2 nanosheets increases channel sizes and stabilizes the GONM structure. By manipulating the mass ratio between GONM and cobalt salt, we optimized the membrane, achieving an exceptional water permeance of 224.2 L m-2h−1 bar−1, surpassing GO membranes. Additionally, the resultant membranes exhibit remarkable underwater anti-oil adhesion performance and efficient separation capabilities for a wide variety of oil-in-water emulsions, with separation efficiencies exceeding 99.1 %. This work provides valuable insights into the intentional manipulation of surface topography and hierarchical nanochannels in membrane materials, paving the way for high-efficiency water treatment solutions.

Tough, antimicrobial, recyclable hydrogel with tree-trunk-inspired core‐sheath structure for efficient all-day desalination

Solar-driven interfacial evaporation, an economically friendly freshwater harvesting technology, faces the challenge of achieving efficient all-day desalination. Inspired by the core‐sheath structure of tree trunks, herein, a hydrogel evaporator features internal vertical lamellar sodium alginate (SA) pores supported by aramid fiber (AF) networks and surface covered with a dense layer of copper sulfide (CuS) and was fabricated through freeze-drying-cycling alternating immersion method. The internal vertical SA lamellar structure endows the hydrogel with strong water transport capability, while the high photothermal conversion ability of the surface CuS layer enables rapid water evaporation. Therefore, as 2D evaporators, the evaporation rate in highly concentrated salt solutions (15 wt%) is up to 2.07 kg m-2 h-1 under 1.0 sun. As 3D evaporators, efficient evaporation is achieved throughout the day by compensating evaporation at the sides and top. Under the irradiation of 0.2 and 0.8 suns outdoors, the evaporation rate of the 3D evaporator can reach 7.47 kg m-2 h-1 and 12.60 kg m-2 h-1, respectively, and its total evaporation is 4.72 times higher than that of the 2D evaporator. Notably, the hydrogel evaporator has excellent anti-salt properties, antimicrobial properties, and recyclability. This work provides valuable guidance for designing and developing practical hydrogel evaporators.

Quantification of irrigation water transport processes in ZiZiphus jujuba garden using water stable isotopes

Quantification of irrigation water transport processes in ZiZiphus jujuba garden using water stable isotopes

Performance of normal-weight and lightweight 3D printed cementitious composites with recycled glass: Sorption and microstructural perspective

The development of sustainable mixtures has been a widely researched topic in the last decade, as the cement and concrete industries are among the most polluting sectors. Recycled materials can eliminate the need for extraction of natural materials through re-utilization of waste, reducing the environmental impact. To date, few studies have analyzed the effects of incorporating recycled glass aggregates on the water transport properties and microstructure of 3D printable mixtures.This study assesses the feasibility of incorporating recycled glass as a replacement for natural aggregate in 3D printable mixtures. For this purpose, three normal-weight and three lightweight mixtures containing 0, 50, and 100 vol.% of recycled glass aggregate as basalt aggregate replacement were evaluated in cast and printed samples. Expanded thermoplastic microspheres (ETM) were included to create the lightweight mixture composition. This experimental work evaluated the effects of incorporating recycled glass, ETM, and the impact of the printing process on the microstructure, sorption, and capillary water porosity (CWP).The printing process has proven to be an influential factor affecting the shape, size, and quantity of porosity. In addition, the printing process was demonstrated to be more influential on porosity formation than the inclusion of recycled glass or ETM. Incorporating recycled glass results in a slight decrease in the PHg porosity, more spherical pores, and lower anisotropic tendency. Furthermore, adding ETM has a filling effect, leading to a more compact microstructure.

TRANSPORT TECHNOLOGIES RELATED TO THE RESTORATION OF SHIP CARGO MECHANISMS WITH THE LATEST MODIFIED EPOXIES

The development of transport technologies today requires not only the creation of bases for the optimal technical use of vehicles, their technical operation, but also their maintenance and repair. One of the main tasks of transport technologies is the search for new promising scientific directions and their implementation in practice, as well as ensuring the effective use of the latest technologies and innovative methods for the construction or repair of water transport facilities. In this respect, the use of epoxy-based polymer composites is promising. They are characterised by improved adhesive and cohesive properties compared to other known oligomers, which determines the wide range of their application in water transport. In order to improve the properties of epoxy-based adhesives, additives of different physical nature are introduced into the epoxy matrix at the initial stage of moulding. This paper investigates the effect of the modifier d-ascorbic acid on the thermal properties of epoxies to obtain a material intended for the restoration of ship loading mechanisms. Based on the dynamics of heat resistance as a function of d-ascorbic acid concentration, the optimum content of the additive in the epoxy compound was determined, which is 1,25...1,50 pts.wt.for 100 pts.wt.of epoxy resin. The introduction of a modifier into the epoxy oligomer provides composites with the highest heat resistance values of all the materials studied. The heat resistance values increase from 341 K (for the epoxy matrix) to 352...354 K. The mechanism of increasing the heat resistance of an epoxy matrix in the presence of a modifier is substantiated, which involves the interaction of epoxy resin with an additive and a hardener as a result of chemical reactions. As a result of the reactions of structure formation of the compound based on epoxy oligomer and modifier in the presence of polyethylene polyamine, mainly strong chemical bonds of C-O, NH2, O-NH2, N=O, N-O-H, C=N type are formed, which largely determine the increase of cohesive strength of the newly formed modified epoxy matrices. It should be noted that it is the cohesive strength of the matrix that determines the thermal resistance of the material at elevated temperatures. It was found that the maximum glass transition temperature (333 K) was observed for the modified material containing d-ascorbic acid at 1,5 pts.wt. At this level of additive, the maximum values of both heat resistance and glass transition temperature were observed compared to the original epoxy matrix (327 K). At this modifier concentration, the cross-linking of the compound forms the most cross-linked structural network of an amorphous polymer with the highest number of chemical bonds.

Simultaneous measurement of SO2 and CO2 for sulfur content detection in marine diesel fuel using QCL absorption spectroscopy

Simultaneous measurement of CO2 and SO2 in ship exhaust gases is a common method for assessing compliance with sulfur emission standards. This study develops a new ship exhaust gas analyzer using time-division multiplexing of two quantum cascade lasers for simultaneous detection of the two gas species. A digital circuit integrated with a dual-channel waveform generator and a lock-in amplifier is developed to implement wavelength modulation spectroscopy (WMS) scheme. To enhance the measurement accuracy of SO2 with broadband absorption feature, a novel WMS approach that combines first-harmonic and normalized second-harmonic detection is introduced. A Kalman filter algorithm is employed to further refine the measurement precision. Experimental results show a 30.76% increase in detection accuracy. With a 1 s time resolution, the sensitivities of 13.4 ppb for SO2 and 9.81 ppm for CO2 are achieved. The effectiveness of the prototype for sulfur content detection is demonstrated, aiding emission management of water transport emissions.

Исследование подходов к обустройству инфраструктуры для временного отстоя вагонов на железных дорогах России в различные исторические периоды

Purpose: to determine the relevance of the problem of temporary storage of cars on Russian railways in various historical periods. Consider methodological approaches aimed at eliminating this problem, as well as technical and technological measures. Assess how well the problem of temporary storage of wagons has been developed to date. Methods: when performing the study, the method of retrospective analysis was used. To conduct a retrospective analysis, scientific publications, regulatory documents, educational publications and other literary sources were used. Results: using the provisions of literary sources, the negative impact of excess or concentration of cars in certain places of the railway network on the normal operation of railway transport as a whole has been confirmed. It has been established that the most typical problem of temporary parking of cars is for stations of the railway network located in areas interacting with water transport. For various historical periods, the applied methodological approaches and measures were identified aimed at organizing the temporary parking of cars in order to increase the efficiency of railway transport. Practical importance: the completed study confirmed the relevance of the problem of organizing temporary storage of cars on Russian railways in various historical periods. It has been established that for the current stage of development of railway transport, the most rational solution is the arrangement of special stations for the temporary storage of cars.