bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of repeated sleep deprivation on brain pericytes in mice
Authors: Wu Yan , Li Pengfei , Bhat Narayan , Fan Hongkuan , Liu Meng
Published: August 2023

The damaging effects of sleep deprivation (SD) on brain parenchyma have been extensively studied. However, the specific influence of SD on brain pericytes, a primary component of the blood–brain barrier (BBB) and the neurovascular unit (NVU), is still unclear. The present study examined how acute or repeated SD impairs brain pericytes by measuring the cerebrospinal fluid (CSF) levels of soluble platelet-derived growth factor receptor beta (sPDGFRβ) and quantifying pericyte density in the cortex, hippocampus, and subcortical area of the PDGFRβ-P2A-CreERT2/tdTomato mice, which predominantly express the reporter tdTomato in vascular pericytes. Our results showed that a one-time 4 h SD did not significantly change the CSF sPDGFRβ level. In contrast, repeated SD (4 h/day for 10 consecutive days) significantly elevated the CSF sPDGFRβ level, implying explicit pericyte damages due to repeated SD. Furthermore, repeated SD significantly decreased the pericyte densities in the cortex and hippocampus, though the pericyte apoptosis status remained unchanged as measured with Annexin V-affinity assay and active Caspase-3 staining. These results suggest that repeated SD causes brain pericyte damage and loss via non-apoptosis pathways. These changes to pericytes may contribute to SD-induced BBB and NVU dysfunctions. The reversibility of this process implies that sleep improvement may have a protective effect on brain pericytes.
Multiscalar electrical spiking in Schizophyllum commune
Authors: Adamatzky Andrew , Schunselaar Ella , Wösten Han A. B. , Ayres Phil
Published: August 2023

Growing colonies of the split-gill fungus Schizophyllum commune show action potential-like spikes of extracellular electrical potential. We analysed several days of electrical activity recording of the fungus and discovered three families of oscillatory patterns. Very slow activity at a scale of hours, slow activity at a scale of 10 min and very fast activity at scale of half-minute. We simulated the spiking behaviour using FitzHugh–Nagume model, uncovered mechanisms of spike shaping. We speculated that spikes of electrical potential might be associated with transportation of nutrients and metabolites.
Calibration and validation of ultraviolet time-of-flight mass spectrometry for online measurement of exhaled ciprofol
Authors: Li Xiaoxiao , Chang Pan , Liu Xing , Zhao Zhongjun , Li Wenwen , Kang Yi , Duan Yixiang , Zhang Wensheng
Published: August 2023

Ciprofol in exhaled breath could be measured online by ultraviolet time-of-flight mass spectrometry (UV-TOFMS). This study presents the calibration method and validation results of UV-TOFMS for the quantification of ciprofol gas.
Dynamic hydrogen bubbling templated AgSn@SnOx electrocatalyst for selective electrochemical CO2 reduction: adjusting the binding energy of the HCOO* intermediate
Authors: El-Aqapa Hisham G. , Badawy Ibrahim M. , Khedr Ghada E. , Agour Ahmed M. , Sayed Doha M. , Taha Manar M. , Allam Nageh K.
Published: August 2023

Core–shell AgSn@SnOx catalysts demonstrated selective CO2RR towards HCOOH with a faradaic efficiency of 96 ± 4.9% and partial current density of −10.46 ± 0.35 mA cm−2 by adjusting the binding energy of the HCOO* intermediate.
Enhancing selectivity for semi-hydrogenation of Ni by periodic isolation in the MM′X structure
Authors: Liu Yinglei , Xu Changjin , Yang Bo , Meng Xiangying , Qin Gaowu , Li Song
Published: August 2023

Over-hydrogenation of ethylene on Ni atoms is suppressed by isolating Ni in the MM′X lattice.
MB3P2S10 (M = Rb, Cs): two new alkali metal thioboratephosphates with [B6P4S20] T3-supertetrahedra
Authors: Zhou Jiazheng , Su Xin , Luo Ling , Li Junjie , Yu Feng
Published: August 2023

Two new alkaline metal thioboratephosphates, RbB3P2S10 and CsB3P2S10, have been designed and fabricated by the flux method.
Synthesis of a water-soluble naphthalene-based macrocycle and its host–guest properties
Authors: Dong Ming , Qi Wanru , Sun Guang , Xu Kaidi , Ma Yixin , Lv Jing-Fang , Zhao Liya , Zhang Zhi-Yuan , Li Chunju
Published: August 2023

The synthesis of a naphthalene-based macrocycle bearing anionic carboxylato groups on the rims and its complexation with cationic guests in aqueous media have been reported.
Polarizability characteristics of twisted bilayer graphene quantum dots in the absence of periodic moiré potential
Authors: Liu Xiangyue , Wang Xian , Yu Shengping , Wang Guangzhao , Li Bing , Cui Tiantian , Lou Zhaoyang , Ge Hong
Published: August 2023

The largest interlayer polarizability and charge transfer driven by an external field occur in the mis-orientated structures with a size-dependent small angle corresponding to the first appearance of AB stacking.
A comprehensive review of bioleaching optimization by statistical approaches: recycling mechanisms, factors affecting, challenges, and sustainability
Authors: Naseri Tannaz , Beiki Vahid , Mousavi Seyyed Mohammad , Farnaud Sebastien
Published: August 2023

A serious environmental problem is associated with the accumulation of solid waste on the Earth.
Mediation of exciton concentration on magnetic field effects in NPB : Alq3-based heterojunction OLEDs
Authors: Song Jiayi , Wang Cheng , Guan Yunxia , Bao Xi , Li Wan Jiao , Chen Lijia , Niu Lianbin
Published: August 2023

Organic light-emitting diodes (OLEDs) are considered one of the most promising new display technologies owing to their advantages, such as all-solid-state, high color gamut, and wide viewing angle.
Effect of ionic liquids on the microstructure and combustion performance of Shengli lignite
Authors: Hou Xiaowei , Duan Hanyu , He Runxia , Zhou Huacong , Ban Yanpeng , Li Na , Zhi Keduan , Song Yinmin , Liu Quansheng
Published: August 2023

ILs promoted conversion of oxygen-containing groups to ether structures of lignite. Inhibition of combustion was related to content of ether structures.
Construction of composite films using carbon nanodots for blocking ultraviolet light from the Sun
Authors: Bai Yibing , Zhao Bin , Ni Jiaxin , Sun Lianhang , Wang Yuning , Wang Jing , Liu Yu , Han Shiyan , Gao Fugang , Zhang Chunlei
Published: August 2023

A robust carbon nanodot (CND)-based composite film (CND-film) was developed and successfully used to block short wavelength light.
Noble metal-free ternary cobalt–nickel phosphides for enhanced photocatalytic dye-sensitized hydrogen evolution and catalytic mechanism investigation
Authors: Cheng Zhixing , Xu Yiqin , Fei Bin
Published: August 2023

Transition metal phosphides, especially cobalt–nickel ternary phosphides (CoNiP), show remarkable promise as efficient and low-cost alternatives to noble metal catalysts for eosin-Y-sensitized photocatalytic hydrogen evolution.
Enhanced cycle life of starter lighting ignition (SLI) type lead–acid batteries with electrolyte modified by ionic liquid
Authors: Kędzior Paweł , Rzeszutek Waldemar , Wojciechowski Jarosław , Skrzypczak Andrzej , Lota Grzegorz
Published: August 2023

The addition of ionic liquids to the sulfuric acid electrolyte solution in a lead–acid battery inhibits corrosion of current collectors and sulfation of the negative electrode. This increases the service life of the entire device.
Estimating instantaneous frequency of multicomponent signal using optimization strategy in fractional domain
Authors: Xu Liyun , Li Wei
Published: August 2023

Estimating instantaneous frequencies (IFs) overlapped in both time and frequency domains is an important issue in time‐frequency (TF) analysis. In this letter, the TF information of the signal in fractional domain is combined with an optimization strategy to estimate the IF of multicomponent overlapping signals. The method converts the IF estimation into the problem of function fitting in the two‐dimensional plane. First, based on the fractional window function with a specific angle, the energy of the multicomponent signal is concentrated around a certain signal component to obtain a relatively high‐resolution TF representation in fractional domain. Second, the training data set is constructed by the obtained TF representation, which will be used to estimate the IF. At last, the IF curve of the signal component is fitted with an optimization function. Numerical experiments verify the effectiveness of the proposed method under the low SNR.
Performance evaluation of RW‐Quadrotor and Bi‐Quadrotor for payload delivery
Authors: Dalwadi Nihal , Deb Dipankar , Ozana Stepan
Published: August 2023

Payload delivery is one of the many Unmanned Aerial Vehicle (UAV) applications that save time, energy, and human resources. The present simulation study compares rotary‐wing quadrotors (RW‐Quadrotors) and tail‐sitter biplane quadrotors (Bi‐Quadrotors) under payload delivery conditions that help to choose the best UAV for the particular mission. A comparative study is performed based on (i) time taken to accomplish the given mission, (ii) trajectory tracking performance, (iii) motor speed throughout the entire flight envelope, and (iv) remains SoC (State of Charge) after the mission. Furthermore, a Backstepping Controller (BSC) and an Adaptive Backstepping Controller (ABSC) are developed for both UAVs to handle mass changes during flight while Genetic Algorithm (GA) is used for the gain optimization. MATLAB Simulink‐based numerical simulation reveals that the Bi‐Quadrotor has a lower average rotor speed than the RW‐Quadrotor. However, the Bi‐Quadrotor's SoC after the mission is higher than the RW‐Quadrotor, and it took less time to accomplish the mission. The ABSC designed for RW‐Quadrotor and Bi‐Quadrotor effectively handles mass change during the mission. However, the BSC controller increases energy consumption for the Bi‐Quadrotor in the presence of wind gusts.
Performance evaluation technique for screen‐to‐camera‐based optical camera communications
Authors: Yokar Vaigai Nayaki , Le‐Minh Hoa , Ghassemlooy Zabih , Woo Wai Lok
Published: August 2023

The increasing development and utilisation of optical camera communications offer an excellent opportunity for the implementation of the smartphone‐to‐smartphone‐based visible light communications (S2SVLC) system. In this study, the authors experimentally demonstrate that the S2SVLC system can support high‐quality multimedia transmissions by the investigation of the mean square error estimation, peak signal‐to‐noise (PSNR) degradation, bit error rate (BER), and data rate achieved. The experimental analysis has been carried out for different typical practical background illuminations (i.e., normal illumination and dark condition), distances, tilting, and rotation angles. The PSNR and BER are determined for different frame sizes in the S2SVLC system to provide an insight of system performance. Those results indicate that the data transmission at different conditions significantly impacts the system's performance.
Capacity of second spillway of Boguchanskaya HPP
Authors: Gouriev A. P. , Khanov N. V. , Fartukov V. A. , Zborovskaya M. I. , Abidov M. M.
Published: August 2023

The main problem in designing the discharge of water flow from the upstream to the downstream is to ensure the capacity of spillway structures. This article discusses the design options for the design top of the spillway: with water diversion through a short nozzle in the pressure mode and energy dissipation in stilling basin, with the pressure-free and pressure-free passage of water through spillway No. 2 and damping of the flow energy by jet discharge into the lower stream by the inclined face of the threshold in the stilling basin; with no pressure passage and pressure passage of water through spillway No 2 and energy dissipation of the flow by throwing the flow discharge into the downstream by the inclined face of the threshold of a stilling basin; with the passage of building expenses through the sill in no pressure and pressure-type short-nozzle modes, with the spillway No. 2’s horizontal water outlet at the level of 139.5 m, with a jet discharge by a toe-springboard at an angle of 35°, and with the outlet rib's mark of 143.8 m. This article aims to obtain the flow characteristics of the considered spillway option for the period of temporary operation of the hydrotechnical complex.
Investigations on determination of changes in inactive volume of water reservoirs (case study of South Surkhan water reservoir)
Authors: Gapparov Furkat , Mansurov Safar
Published: August 2023

The article develops the change of the reservoir’s useable volume under the effect of turbidity-sediments, considering the turbid discharges' hydrological regime into the reservoir, and proposes a computation technique. Field research was conducted in the South Surkhan reservoir. Based on the data collected from the field research, an electronic map of the reservoir bowl was made, and morphometric indicators were evaluated, considering the formation of muddy sediments in the reservoir. When the standard water level of the water reservoir is 415 meters, the designed water surface area is 65 km2, and the full volume is 800 mln. m3, and according to the results of field research, the full volume of the water reservoir at the level of the normal moisture level is 491.2 mln. m3, the water surface was 72.45 km2. It showed that the full volume of the reservoir was reduced by 38.6 percent compared to the design volume during the operation period, and the water surface area increased by 7.45 km2. The research results allow to determine the change in the useful volume of the reservoir under the influence of turbidity and sediments, to determine the morphometric indicators, and to use the water reserve effectively.
Influence of geographical location on reservoir vegetation formation
Authors: Khaydarov Aziz , Apakxujayeva Tursunoy , Atakulov Dinislam
Published: August 2023

The paper provides information on the vegetation cover area on the reservoir bottom. In the growing shortage of water resources, one of the important tasks is to improve methods for estimating reservoir volume. The vegetation cover of reservoirs influences the quality of the water supply. While the bottom of some reservoirs is drained, this bottom is covered with vegetation, but this trend is not observed in all reservoirs. The Talimarjan and Charvak reservoirs were selected as study sites. As a method, spatial data were selected that were collected using GIS. The results have shown that when the Talimarjan Reservoir is impounded, a considerable part of the reservoir is covered by vegetation of different species, while the bottom of the Charvak Reservoir remains without vegetation. The intensity of eutrophication processes in the reservoir may cause excess nutrients and change the reservoir’s water quality in the near future. To prevent such a situation, reducing the number of plants in the reservoir and increasing water exchange is necessary.
Effects of water level changes in reservoir basin on coastal erosion
Authors: Arifjanov Aybek , Luqmon Samiyev , Ibragimova Zaytuna , Ulashov Q. Ch.
Published: August 2023

In this article, the Chimkurgan reservoir built in the Kashkadarya basin, located in the Qamashi district of the Kashkadarya region, is selected. Considering the change in the water level of the Chimkurgan reservoir, the level of erosion of the shores in the zone of 14 m of water level change on the left bank of the reservoir was considered. Over time, the forces induced by water weaken the soil aggregates, negatively affecting the soil's stability. The density composition of the reservoir coastal soils was determined at the specified heights. The degree of erosion of the reservoir’s banks, depending on the soil type, was also considered. To the bottom of the reservoir, the degree of erosion of coastal soils was determined in the water level change zone at heights of 9 m, 11 m, 13 m, 15 m, 17 m, and 19 m, 22 m, 23 m. It was found that the types of soils obtained from the elevations in the specified place differ from each other. It was determined that the type of soil at these heights is clay, soft soil, and sand, and to a certain extent, the erosion of the banks differs depending on the type of soil.
Improvement of water distribution management methods for operating modes of machine channels
Authors: Glovatskiy Oleg , Djumanazarova Altingul , Saparov Amanbay , Nasirova Naira , Sultonov Akmal , Sattorov Akbarali
Published: August 2023

The ongoing research aims to improve the reliability of irrigation systems, improve methods for managing the water distribution of the operating modes of machine canals, and increase crop yields in the Nukus and Kegeyli regions of the Republic of Karakalpakstan. At present, increasing the efficiency of the operation of machine channels is associated with the development of energy and resource-saving technologies. Pumps that have been in operation for more than 25-30 years, due to physical and obsolescence, operate with low efficiency, emergencies associated with technological regimes with transients. The article analyzes changes in the processes of the hydrodynamics of control systems with optimization of sediment control on water supply structures, the danger of abrasive wear of the flow path of hydraulic units, and experimentally checks the mathematical model for managing the water distribution of operating modes. In this regard, the improvement of the design of elements and the modernization of individual units of pumping units will increase the efficiency of the entire system of machine water lifting. Recommendations are given on the inclusion of settling tanks in the composition of the head waterworks, carrying a large number of suspended sediments (more than 0.2–0.5 kg/m3) and systems for their purification.
Anti-shock pneumohydraulic damper
Authors: Jonkobilov U. , Jonkobilov S.
Published: August 2023

The article is devoted to the analytical calculation of the main parameters and dimensions of a pneumohydraulic hydraulic shock damper with a decrease in pressure installed at the beginning of a pressure pipeline to reduce the emergency consequences of the intensity of shock waves, taking into account the polytropic process of air in the damper. Based on the results of analytical studies of the wave equations of non-stationary pressure movements for the proposed hydraulic shock damper, dependences were obtained for calculating the maximum and minimum impact heads in the first period of pressure fluctuations, considering the polytropic index.

To substantiate the reliability of the proposed dependencies and the economic dimensions of the damper design, comparative calculations of analytical studies with experimental data and data from other authors were performed. Comparative calculations prove the reliability of the proposed dependences obtained by the analytical method of solutions to the known equations of motion of hydromechanics, continuity, and state of the air in the damper.
Fundamentals of hydraulic calculations of water softening structures in drip irrigation technology (in case of Zarafshan river)
Authors: Yangiev A. A. , Salyamova K. , Omarova G. , Adjimuratov D. S. , Azizov Sh. N. , Serikkhanov B.
Published: August 2023

This article presents the results of field studies on the study of the process of sediment settling in the settling tanks of the drip irrigation system carried out on farms in the Akdarya and Ishtikhan districts of the Samarkand region, which are supplied with water from the Zarafshan River. Calculation of the process of settling sediments in sedimentation tanks was carried out according to the method of A.G.Khachatryan, and a graph of the relationship between the length of the sedimentation tank and the degree of sediment clarification was determined. As a result, recommendations have been developed to substantiate the optimal parameters of sedimentation tanks for various natural conditions.
Calculation of release time of water in soil layer
Authors: Fatkhulloev A. , Otakhanov M. , Khoshimov A. , Bakhromova D.
Published: August 2023

This article discusses the importance and principles of drainage system design in irrigated land. Weather and the type of cultivated crop are analyzed as the main factors for the drainage system. Also, since there is no single empirical formula for determining the duration of groundwater discharge through ditches for designing efficient and sustainable drainage systems in areas where water-saving irrigation technologies are introduced, a certain new method for determining this time is presented as a recommendation.
Study of technology to reduce formation of collector-soil water in saline soil conditions
Authors: Urazkeldiyev Abduvokhid , Isabaev Khasimbek
Published: August 2023

This article presents the results of scientific research aimed at the rational use of water resources in the Khorezm region under the conditions of water shortage, prevention of secondary salinization of irrigated areas, reduction of water wastage from irrigation networks, and improvement of efficient water use technologies in reducing the water formed in collector-sink networks.
Influence of flood control facilities on water level in downstream of river system Sai Gon -Dong Nai
Authors: Markova Irina , Khanh Phan Khanh , Raimova Iqboloy
Published: August 2023

Ho Chi Minh City, Vietnam's largest city, located on the lower reaches of the Sai Gon-Dong Nai (SG-DN) river system, is facing increasingly severe flooding due to changes in river flow and water levels. This article presents the results of a study to assess the impact of hydraulic structures located in the upper reaches on the water level in the lower reaches of the SG-DN River. As part of a study to assess the impact of upstream reservoirs and flood control structures on the water level in the lower reaches of the SG-DN River, hydrological data of the river network were collected. A hydraulic model was developed based on a digital elevation model (DEM) using the software package Mike 11, Mike 21 and Mike Flood. The water level of the Sai Gon River from the upper reaches to the Thu Dau Mot measuring station depends on the Dau Tieng reservoir, and the Tri An reservoir directly affects the water level in the river section from behind the Tri An dam to the Dong Nai section in the Tam An - Long Phuoc area. In the sections of the Sai Gon and Dong Nai rivers, which are less affected by the two overlying reservoirs, it is necessary to develop preventive measures to supply sufficient fresh water to meet the population's and industries' needs. In areas prone to flooding and underflooding due to the operation of anti-flood locks, it is also necessary to reconstruct hydraulic structures (raise the elevations of foundations, expand drainage systems, build reservoirs for collecting flood water, etc.)
Hydraulically most advantageous pipe diameters for supplying water to reclaimed land
Authors: Dzhumagulova Nazira , Abdulameer Layth
Published: August 2023

Recently, some countries have been using treated wastewater to irrigate crops. In the administrative district of Kerbela, they also decided to borrow the experience of these countries, but on the condition that the treated wastewater would be environmentally safe in terms of sanitary and hygienic terms. It is necessary to comply with the requirements for the quality of water for irrigation of crops, and also not cause damage to the environment, soil and plants. From the treatment facilities of Kerbela 1000000 m3/day (1.16 m3/s) of water are formed, but the project provides for an increase to 400000 m3/day (4.63 m3/s) therefore, the selection of the diameter of the pipes for supplying water to the irrigation fields is provided for two flow rates. For preliminary calculation, the WaterCAD V8i simulation model was used, with the help of which the optimal pipe diameter and hydraulic characteristics of the flow were selected. Based on the results of the model, the optimal dimensions of the pipe diameter, modes of fluid movement and head loss are determined. The choice of pipe material was made from four types (ductile iron, GRP, concrete and plastic). The novelty of the work lies in the fact that for the first time a main scheme is being laid for transporting treated wastewater in this region and the hydraulic characteristics of water movement are being studied.
Recommendations for the assessment and forecast of shore deformations in the average flow of the Amudarya river
Authors: Norkulov Bekhzod , Nazaraliev Dilshod , Raimova Iqboloy , Vafoeva Ozoda
Published: August 2023

The paper presents the results of the field and numerical studies of the bank destruction in the middle section of the Amudarya River. The article presents the main factors of destruction of the banks during floods and low water flow. In addition, recommendations for protecting the coast from erosion are also developed. As a result of research into the process of intensive local reshaping of an easily eroded channel, hydraulic schemes have been developed for the occurrence of local bank erosion both in steady and unsteady motion in an open stream.

The recommendations are based on some patterns of interaction between the river channel and the flow during the period of low water and high-water flow. The external manifestation of this interaction is the coastal deformations, leading to the planned displacement of the channel.
Calculation of planned flows taking into account deformations of bottom sediments in a dam-free water intake
Authors: Bazarov Dilshod , Norkulov Bekhzod , Mamataliev Adkham , Vafoeva Ozoda , Nazarova Shokhida
Published: August 2023

The article presents the results of numerical studies carried out by the authors of the existing problems in assessing the intensity of channel processes in the territory of the damless water intake of the Amudarya river. As well as the development of hydraulic regimes and flow regimes of sediment flow for the proposed structures based on experimental and numerical studies for the proposed structures is the main goal of research work. In the course of numerical studies, depths, changes in water flow were determined which elements of flow in straight and curvilinear channels were initially. As part of the numerical studies, the flow spreading conditions (vectors of medium-depth velocities) in specific time intervals and transitions in the water intake area were studied.
Operation of locomotives of diesel traction on hilly section of railway
Authors: Ablyalimov Oleg , Avdeyeva Anna
Published: August 2023

The results of substantiation of the kinematic parameters of the logistics of freight trains and locomotives of diesel traction are presented, taking into account the stopping process at the intermediate and terminal stations of a virtual hilly section of the railway. Tabular and graphic data of the logistic kinematic parameters of the movement of the studied freight trains and locomotives of diesel traction are obtained, taking into account the organization of stops on a virtual hilly section of a high-speed railway, as well as regression equations for determining their of numerical values, which are recommended for implementation in the practice of the locomotive complex of the Uzbek railways.
Torsional oscillations of armature shaft of generator of main diesel locomotive in diesel start-up mode
Authors: Djanikulov A. T. , Abdulatipov U. I.
Published: August 2023

The article considers a mechanical model of torsional vibrations in the starting system of a diesel generator (DG) with two concentrated mass moments of inertia and a previously unaccounted factor of torsional vibrations between the traction generator and the crankshaft of a diesel locomotive of the UzTE16M type. For this model, the Lagrange method is used to derive a system of equations for mass oscillations along the generalized coordinates of "kinematic" and elastic oscillations between the masses of the armature of the traction generator and diesel engine with a variable mass moment of inertia. For the resulting system of equations, by the method of operational calculus, solutions were made for the accepted functions of mass moments of inertia, moments of driving forces, and resistances. Based on the developed model, it is recommended to determine the angular velocity of the diesel crankshaft which is currently used.
Beam vibration due movement of overweight cargoes on reinforced concrete bridges at different ground conditions
Authors: Berdibaev M. , Mardonov B. , Nishonov N. , Rakhimjonov Z.
Published: August 2023

The article deals with the vibrations of a reinforced concrete bridge whose supports are located in soils with different properties under the action of overweight cargoes. The assumption is made that the structure deformed in the elastic zone when Hooke's law is valid. The Fourier method is used to solve the problem. The results are presented as graphs of changes in stresses and deflections along the coordinate and time, which are accompanied by analysis. When a concentrated load is applied, depending on the stiffness coefficient of the connection between the supports and the ground, stresses exceeding the limit load can occur in the middle of the beam cross-section. Thus, in the calculations, it is necessary to consider the nature of the interaction of the supports with the surrounding soils when calculating the beams for the action of moving loads.
Calculation of Continuous Reinforced Concrete Bridges And Overpasses Inseismically Hazardous Areas
Authors: Shermukhamedov U.Z. , Karimova A.B , Zakirov B.S.
Published: August 2023

In recent years, in the Republic, the design and construction of continuous reinforced concrete bridges and overpasses were conducted at a colossal pace. Foreign advanced technologies, methods, and software systems were taken into account. Foreign experience in studying rubber-metal bearing parts of bridges and overpasses was analyzed. The article presents the calculation of a continuous reinforced concrete overpass for seismic impacts using the finite element method in the framework of the linear spectral theory. Numerical calculations have shown that the bearing part of the right end of the overpass does not allow the span to fall from the abutment because the maximum displacement of the rubber-metal bearing part is 0.2 m. As a result, the span structure and overpass supports have an overestimated margin of safety for an 8-point earthquake, according to MSK-64.
The effect of increasing loads on foundations of operating bridges
Authors: Salixanov S. S. , Zokirov F. Z. , Xakimova Y. T. , Ismailova G. B.
Published: August 2023

This article examines the road bridge over the Karadarya River on the 5th km of the exploited Andijan –Pakhtaabad route R135 Highway. In this case, the effect on the load-bearing capacity of its foundation on ShNQ 2.05.03-12, which is currently in effect, on the replacement of the bridge Intermediate Unit (highway bridge designed and built according to the temporary load classes N30 and NK-80, N10 and NG60) into the temporary load class A14 and NK-100, or on the load-bearing capacity of the Intermediate Unit in increasing its load capacity, was considered. Recommendations have also been made on the maximum increase in the class of permanent and temporary load falling on the foundation of this bridge, which is in operation.
Influence of engineering and geodynamic processes on stability of transport infrastructure
Authors: Djabbarov S. T. , Mukarramov R. H.
Published: August 2023

The article deals with the issues of the mechanism of development of landslides and the factors acting on them, the classification of engineering and geodynamic processes, the division of landslides by types and volumes, as well as the development of landslides by years, and periods (seasons) on the new railway line "Tashguzar-Baisun-Kumkurgan". The number of dangerous geological processes on the adjacent Tashguzar-Boysun-Kumkurgan railway from 2006 to 2020 was 370. In quantitative terms, their activity by year fell on 2007-2010, and the next phase continued in 2012-2014.
Calculation of mass transfer process in vertical sedimentation tank and construction of CFD model
Authors: Rizaev A.N. , Adilov K.A. , Xushvaqtov D.Q. , Ergashev Q.X. , Bakhramov U. , Rikhsikhodjaeva G.R. , Umarov U.V.
Published: August 2023

The development of a numerical model of mass transfer in a vertical pion is considered. The reconstruction was carried out in a room with a three-dimensional exchange of contaminants and a potential flow. Clear contrast plans were used for numerical integration. The results of the numerical study are presented in this paper. A quirk of the constructed numerical demonstration is the plausibility of agent-based calculation of structures in three-dimensional space. An auxiliary development of this work should be carried out by creating a mass transfer control model in settling tanks based on the model of a culminating liquid jet in a tornado vortex.
Mathematical modeling of structured and Newtonian fluids in associated layer
Authors: Kayumov Sh. , Mardanov A. P. , Tuychieva S. T. , Kayumov A. B.
Published: August 2023

In this paper, a mathematical model of the process of fluid filtration in underground layered formations is considered and numerically solved as raw material for generating electrical energy. The objects of the filter are anomalously structured and Newtonian fluids. Computational algorithms are built using iteration, direct and streaming differential sweep methods. An analysis of the numerical solution of the problem has been carried out. The number of flows between reservoirs was determined, as well as the position of the boundaries of disturbances, taking into account the dynamics of reservoir development.
Substantiation of technology of using collector-drainage water for cotton irrigation
Authors: Urunboev Sadriddin
Published: August 2023

The article has developed the optimal options for the use of collector-drainage water as an additional source in the active layer of soil during irrigation of collector-drainage water of cotton variety "An-Bayaut-2" in Saykhunabad district of Syrdarya region, which is 567 m3/ha. Innovative technologies for irrigating cotton with collector-drainage waters using the nuclear-physical method for determining the dynamics of water absorption in the active layer of soils with low salinity allow achieving water saving and a high yield of cotton 4.68 c/ha, saving 13-14% of river water and additionally net income in the amount of 1,150,000 UZS per hectare.
Hydraulic resistances of eroded riverbed and assessment of their sustainability
Authors: Baymanov Kenesbay , Shaniyazov Gulmurat , Uzakov Torebek , Baymanov Ruslan
Published: August 2023

In the world, due to the shortage of water resources, the most important issues are the rational use of water resources, the assessment, and the improvement of the capacity of riverbeds and channels. In this regard, research developments on improving the methods of the hydraulic calculation of the resistance and the stability of mobile river channels and channels are of particular importance. The results of some theoretical and experimental studies of hydraulic resistances and the stability of watercourses by scientists in the CIS and abroad are considered. The analysis of massive field data on the Darcy coefficient (Shezi) of earth channels covered in a sandy mobile bed is performed. With a change in the flow velocity field, the roughness of the channel surface changes, changing its size and shape, which determines the channel's resistance to flow movement. It is established that in stable channels with certain widths, the flow velocity is evenly distributed, having one maximum along the channel axis, and the movement is carried out in the form of a compact single jet along the flow cross-section. With changes in hydraulic conditions, the curvature of the isotopes is observed, the flow tends to split, and several closed systems of rotating the jet appear, which are signs of the development of channel deformations.
Monitoring agricultural land areas using GIS-online program EOS DA: case study of Andijan region
Authors: Oymatov Rustam , Musaev Ilhomjon , Bakhriev Mukhammad , Aminova Guljahon
Published: August 2023

This research aims to look at the use of Earth observing system data analytics (EOS DA), an interactive online system, for agricultural land monitoring in Uzbekistan. With the increasing relevance of digital technology in agriculture, there is a need to investigate innovative approaches for improving land quality monitoring and benchmarking crop conditions and productivity indicators, especially concerning degraded soil processes. The agricultural sector can benefit greatly from the start-up of interactive online digital technologies. Scientific and practical research can be advanced by leveraging existing crop monitoring and forecasting systems and adding components of digital agricultural production systems. Regular crop monitoring adds to higher production and land productivity, both of which are critical in modern agriculture. To reach these goals, modern technologies and the usage of geo-information and remote sensing data must be integrated. The primary goal of this project is to use EOS DA to assist in the continued improvement of agricultural land monitoring in Uzbekistan. The study intends to provide significant insights and recommendations for optimizing agricultural practices and maximizing land productivity by utilizing this interactive online approach. Integrating EOS DA and other geospatial data can result in more informed decision-making and better resource management in the agricultural industry. Finally, using EOS DA, this work aims to contribute to the continual improvement of agricultural land monitoring in Uzbekistan. The study intends to improve agricultural practices and promote sustainable land management in the country by leveraging the potential of interactive online tools and incorporating geospatial information.
Mathematical modeling of salt concentration change process in two-layer aqueous media
Authors: Daliev Sherzod , Karshiev Dilshod , Islamov Yuldosh , Sharipova Umida
Published: August 2023

A mathematical model was developed to monitor and predict changes in salt concentration in groundwater in a two-layer environment, representing the process of salinization and swamping. A qualitative analysis of scientific research on the problem is provided. Since the process is represented by a differential equation, effective numerical computational algorithms were developed to solve the problem of salt concentration change in groundwater based on a stable disclosure scheme with high-order accuracy relative to time and spatial variables. Mathematical models of salt transport during geo-filtration processes were improved, and computational algorithms were developed, taking into account such important parameters as the physical and mechanical properties: water loss coefficient, diffusion coefficients, and filtration rates depending on the water level. The results obtained based on these developed numerical algorithms were analyzed. Before introducing new technologies, recommendations were developed to predict changes in salt content in water using an effective numerical algorithm. Based on the laws of motion of wastewater flows, it was noted that it is possible to conduct experiments using algorithms to determine the changes in distance and velocity of wastewater propagation with water-soluble chemicals and active properties in soil layers.
Monitoring dynamics of green spaces in Surkhandarya region based on remote sensing data of climate change
Authors: Jumanov Azamat , Khudayberganova Marguba , Mirazimova Gulbahor , Radjabov Yorkinbek , Umarov Nurali , Samatova G.
Published: August 2023

Smallholder farmers in Uzbekistan have been facing severe climate-related hazards, particularly highly variable drought. Climate change-induced rise in temperature is the main impetus for more reforms and adoption of modern technologies in the agricultural sector. This article analyzes the data of 2 weather stations, including Kamashi and Shakhrisabz, in 2017, 2018, and 2019 to study the effects of climate change in the Surkhandarya region and its border areas. These weather stations provide temperature, precipitation, relative humidity, and humidity deficit information. In addition, Landsat 8 OLI images for the study area were used for land cover change analysis in 2010, 2015, and 2020. In addition, NDVI analysis for the studied area was also carried out. From these data, it can be concluded that intensive horticulture plantations implemented in the region effectively reduce climate change's impact on the agro-economic sector.
Numerical solution of problem of equilibrium of parallelepiped in stresses
Authors: Khaldjigitov Abduvali , Tilovov Otajon , Djumayozov Umidjon
Published: August 2023

Usually, planar and spatial problems of the theory of elasticity in stresses are solved using the Airy or Maxwell stress function, respectively. Solving a plane problem usually comes down to solving a biharmonic equation. In the spatial case, it can be solved by the Castigliano variational method. This work is devoted to the mathematical and numerical solution of the spatial problem of elasticity theory directly concerning stresses. In this case, the boundary value problem consists of three equilibrium equations and three Beltrami-Michell equations with the corresponding boundary conditions. At the same time, equilibrium equations are considered as missing boundary conditions. Symmetric finite-difference equations are constructed, and the problems of equilibrium of a parallelepiped under the action of domed and uniformly distributed loads are solved numerically. The reliability of the results obtained is substantiated by comparing the numerical results with the wellknown Filonenko-Borodich solution and with the results of solving the boundary value problem of the equilibrium of the parallelepiped with respect to displacements.
Impact of separately located obstacles on air flow movement calculation
Authors: Salokhiddinov A. , Savitskiy A. , Ashirova O. , Razzakov R.
Published: August 2023

In hydrodynamic calculations, the confederation of the right set of coordinates of a continuous medium (gas, liquid) becomes complicated because it makes the calculation mechanismspecific and tied only to a specific object. The paper is devoted to an improved method to calculate the small-scale circulation of the surface layer of the atmosphere in urban areas with many isolated buildings from each other. The proposed method will work for explicit and implicit schemes for calculating the transport equations and conservation of momentum of motion. It is designed to calculate the small-scale circulation of the surface layer of the atmosphere in urban areas with many isolated buildings from each other. The method allows for consideration of the interaction of a continuous medium flow with impenetrable obstacles discretely and randomly located inside the calculation area. This method will be helpful when calculating microcirculation in urban development.
Analysis of chlorophyll “a”, “b”, and carotenoids in leaves of oriental maple, biota, common oak, and chestnut trees resistant to harmful substances emitted by motor vehicles in Tashkent city
Authors: Khodjibabayev Husan , Ismailkhodjaev Bahadir , Abdukodirova Malokhat , Mavlyanova Dildora , Israilov Ibrokhim , Samandarov T.
Published: August 2023

The work is devoted to the composition of the atmospheric air on the main streets, the level of traffic on these streets, the selection of resistant species of phenol trees for growing ornamental trees, and the laws of changing the number of pigments in these trees depending on the streets and season in the Republic of Uzbekistan. At the same time, the types of ornamental trees and their resistance to pollution from the pollution of carbon dioxide, nitrogen oxides, and sulfur dioxide are mainly represented by atmospheric air pollution.
Comparison of operating costs of reinforced concrete bridges and overpasses with different static schemes
Authors: Shermukhamedov U. Z. , Karimova A. B. , Abdullaev A. R. , Khakimova Ya. T.
Published: August 2023

The article considers two options for the design of an overpass with a beam-cut and a beam-continuous static scheme. An inspection of the technical condition of beam-cut reinforced concrete bridges in operation in Tashkent built in 1970-90 was conducted. Estimating the maintenance costs of overpasses with different static schemes operating for the last 50 years shows that the continuous reinforced concrete option drastically reduces the cost of repair work in operation. This, in turn, has a cumulative effect on the development of the bridge-building industry in the Republic of Uzbekistan. The predicted operating costs of overpasses with different static schemes during operation for 50 years showed that in a continuous reinforced concrete option, 435,803,803 soums are saved annually. The most important thing is that the proposed solution dramatically reduces the cost of repair work. This, in turn, has a cumulative effect on the development of the bridge-building industry in the Republic of Uzbekistan.
Design characteristics of road embankments made of sandy soils
Authors: Kayumov A. D. , Kayumov D. A. , Ruziev I. I.
Published: August 2023

Sandy soils are widespread all over the world, including in Uzbekistan, and they are widely used in the construction of highways. Therefore, several regulatory documents have been developed that normalize their design characteristics.

However, in the existing regulatory documents, the design characteristics of sandy soils of road embankments of highways used in the design of road coverings (modulus of elasticity E, angle of internal friction φ, specific adhesion C) are not normalized depending on the degree of compaction, calculated humidity and the content of dusty and clay particles in such soils. To solve these problems, special laboratory and field studies were conducted, the results of which are given in this article.
Investigation of mechanical activation of steelmaking slag and obtaining fine filler
Authors: Turgunbayeva J. R. , Ismoilova G. B. , Juraev K. M.
Published: August 2023

The article presents the results of the mechanical activation of steel-smelting slag affecting the properties of the gypsum composition. As a result of the study, parameters were identified that characterize the reactivity of the slag during mechanical activation. It was established that the increase in the number of Bronsted active adsorption centers on the surface of the formed powders is responsible for their reactivity. However, the maximum increase in surface activity leads to a large percentage of residue on the sieve. Also, polynomial models were obtained that adequately describe the entire process of mechanical activation of waste from metallurgical production.
Modeling gas energy process of underground coal combustion
Authors: Yakubov S. I. , Turdiev M. Sh. , Temirova D. U. , Qurbonov A. R.
Published: August 2023

Protective coal pillars in underground mining are technological losses in the technology of extracting coal at the Angren deposit. During the mine operation, a significant part of the coal remains in the mine space. Extracting them is not possible with traditional energy-mechanical technologies. The paper considers a new extraction technology -energy-heat technological unmanned extraction of brown coal energy from the underground space of spent mine fields. The research results on the experimental sites of the technology of underground combustion of brown coal are presented. A simulation topological scheme of coal pillar combustion with a special chamber has been implemented. The burning rates of coal and heat fluxes in time are determined. The possibility of extracting the energy of coal in the form of a physical heat flow from the underground space of the mine to the daylight surface has been established.