bluuebunny/crossref_metadata_2025 huggingface dataset:
Toward a molecular understanding of the conductivity of lithium-ion conducting polyanion polymer electrolytes by molecular dynamics simulation
Authors: Hua Haiming , Huang Boyang , Yang Xueying , Cheng Jun , Zhang Peng , Zhao Jinbao
Published: October 2023

A comprehensive quantitative study on the structural factors to deepen the molecular understanding on the conductivity of lithium-ion conducting polyanions polymer electrolytes.
Mechanism of optical limiting in metalloporphyrins under visible continuous radiation
Authors: Zhang Qian , Lu Bishuai , Liu Shan , Lü Xiangfei , Cheng Xuemei
Published: October 2023

Both the Kerr effect and thermal nonlinear optical effects are studied simultaneously using cw lasers in metalloporphyrin compounds. The optical limiting performance of Zn-porphyrins is demonstrated and its dependence on sample position is examined.
Multivariate metal–organic frameworks generated through post-synthetic modification: impact and future directions
Authors: Smith Kyle T. , Stylianou Kyriakos C.
Published: October 2023

Reticular chemistry has proven to be invaluable over time, thanks to the structural versatility, and tailored porosity observed in structures like metal–organic frameworks (MOFs), covalent–organic frameworks (COFs), and metal–organic polyhedra (MOPs).
Binuclear cobalt(ii) and two-dimensional manganese(ii) coordination compounds self-assembled by mixed bipyridine-tetracarboxylic ligands with single-ion magnet properties
Authors: Wu Dong-Qing , Kumari Kusum , Wan Yi , Gao Xueling , Guo Mengxi , Liu Genyan , Shao Dong , Zhai Bin , Singh Saurabh Kumar
Published: October 2023

A rare binuclear cobalt(ii) and the first 2D manganese(ii) coordination compounds constructed by mixed bipyridine-tetracarboxylate were reported to exhibit field-supported slow magnetic relaxation behavior.
Regulating and identifying the structures of PdAu alloys with splendid oxygen reduction activity for rechargeable zinc–air batteries
Authors: Qiao Sicong , Shou Hongwei , Xu Wenjie , Cao Yuyang , Zhou Yuzhu , Wang Zhouxin , Wu Xiaojun , He Qun , Song Li
Published: October 2023

PdxAuy alloys with gradient elemental ratios are demonstrated to understand the synergism of the ensemble and ligand effects in catalyzing the ORR. This study provides valuable insights into the rational regulation and catalytic chemistry of alloys.
Stimuli-cleavable moiety enabled vinyl polymer degradation and emerging applications
Authors: Zheng Jie , Png Zhuang Mao , Quek Xian Chun Nicky , Loh Xian Jun , Li Zibiao
Published: October 2023

This review delves into degradable vinyl polymers with stimuli-cleavable moieties, their chemistry, mechanisms, and applications in environmental remediation, drug delivery, advanced functional materials, and surface modification.
Base-mediated carboxylation of C-nucleophiles with CO2
Authors: Luo Yanlong , Huang Wenbin
Published: October 2023

Carbon dioxide (CO2) is an available, abundant, and renewable C1 resource, which could be converted into value-added chemicals.
A novel label-free electrochemical immunosensor for the detection of heat shock protein 70 of lung adenocarcinoma cell line following paclitaxel treatment using l-cysteine-functionalized Au@MnO2/MoO3 nanocomposites
Authors: Chen Yi-An , Shie Ming-You , Ho Chia-Che , Ye Sheng-Wen , Chen I.-Wen Peter , Shih Yu-Yin , Shen Yu-Fang , Chen Yi-Wen
Published: October 2023

The future of precision medicine hinges on non-invasive cancer biomarker sensors. These sensors promise high accuracy, affordability, and time-efficiency, revolutionizing risk assessment, early detection, disease monitoring, and treatment evaluation.
N-(2-(Diphenylphosphino)ethyl)-2-alkyl-5,6,7,8-tetrahydro-quinolin-8-amines iron(ii) complexes: structural diversity and the ring opening polymerization of ε-caprolactone
Authors: Wang Yun , Zhang Wenjuan , Wang Xing , Zuo Weiwei , Xue Xiaopan , Ma Yanping , Sun Wen-Hua
Published: October 2023

A series of 2-alkylated N-(2-(diphenylphosphino)ethyl)-5,6,7,8-tetrahydro-quinolin-8-amines-iron(ii), activated with LiCH2SiMe3, efficiently initiated the ROP of ε-caprolactone with TOF up to 8.8 × 103 h−1, producing PCL within 9.21–24.3 × 104 g mol−1.
Mesoporous CeO2-supported ultrafine PdCu nanoparticle catalyst for selective hydrogenation of alkynols
Authors: Zhang Cheng , Zheng Yi , Li Jianfeng , Cao Hongzhang , Xu Yanhui , Liu Weisheng , Dong Zhengping
Published: October 2023

Bimetallic PdCu nanoparticles were anchored on mesoporous CeO2, the obtained PdCu@CeO2 catalyst showed high selectivity for alkynols hydrogenation to produce high value-added enols.
Integrated microfluidic devices for point-of-care detection of bio-analytes and disease
Authors: Behera Prateechee Padma , Kumar Natish , Kumari Monika , Kumar Sumit , Mondal Pranab Kumar , Arun Ravi Kumar
Published: October 2023

Micro- and nanofluidics have enabled the possibility of miniaturized analytical systems, which are commonly known as lab-on-a-chip (LOC) devices.
Effect of molar ratio and concentration on the rheological properties of two-component supramolecular hydrogels: tuning of the morphological and drug releasing behaviour
Authors: Hansda Biswanath , Mondal Biplab , Hazra Soumyajit , Das Krishna Sundar , Castelletto Valeria , Hamley Ian W. , Banerjee Arindam
Published: October 2023

Self-assembled supramolecular hydrogels offer great potential as biomaterials and drug delivery systems.
Promising approaches and kinetic prospects of the microbial degradation of pharmaceutical contaminants
Authors: Karishma S. , Yaashikaa P. R. , Kumar P. Senthil , Kamalesh R. , Saravanan A. , Rangasamy Gayathri
Published: October 2023

Pharmaceutical pollutants, stemming from waste disposal, animal discharge, and drug manufacturing, pose health risks to humans and animals through their biological activity.
GFRNet: Rethinking the global contexts extraction in medical images segmentation through matrix factorization and self‐attention
Authors: Chen Lifang , Wang Shanglai , Wan Li , Su Jianghu , Wang Shunfeng
Published: October 2023

Due to the large fluctuations of the boundaries and internal variations of the lesion regions in medical image segmentation, current methods may have difficulty capturing sufficient global contexts effectively to deal with these inherent challenges, which may lead to a problem of segmented discrete masks undermining the performance of segmentation. Although self‐attention can be implemented to capture long‐distance dependencies between pixels, it has the disadvantage of computational complexity and the global contexts extracted by self‐attention are still insufficient. To this end, the authors propose the GFRNet, which resorts to the idea of low‐rank matrix factorization by forming global contexts locally to obtain global contexts that are totally different from contexts extracted by self‐attention. The authors effectively integrate the different global contexts extract by self‐attention and low‐rank matrix factorization to extract versatile global contexts. Also, to recover the spatial contexts lost during the matrix factorization process and enhance boundary contexts, the authors propose the Modified Matrix Decomposition module which employ depth‐wise separable convolution and spatial augmentation in the low‐rank matrix factorization process. Comprehensive experiments are performed on four benchmark datasets showing that GFRNet performs better than the relevant CNN and transformer‐based recipes.
Network‐constrained unit commitment‐based virtual power plant model in the day‐ahead market according to energy management strategy
Authors: Pirouzi Sasan
Published: October 2023

Energy management of a virtual power plant (VPP) that consists of wind farm (WF), energy storage systems and a demand response program is discussed in the present study. The introduced strategy is realized at the electrical power transmission level and takes into account the collaboration between VPPs in day‐ahead energy and reserve markets. One notable feature of the proposed strategy is attempting to make the revenue of VPPs close to the operating cost of generating units as much as possible. The objective function is subjected to the network‐constrained unit commitment model, up and down reserve requirements and the proposed VPP constraints. This method is taking into account the uncertainty in system and VPP loads, day‐ahead market energy and reserve price and WF power generation. This strategy is applied as hybrid stochastic‐robust scheduling to the VPP at the electrical power transmission level, where the scenario‐based stochastic programming models the uncertainty of day‐ahead market prices, and the bounded uncertainty‐based robust optimization has been adopted to model the uncertainties related to the load and WF power. Scheme has been tested on IEEE systems. According to the obtained results, the proposed coordination of VPPs in the mentioned markets demonstrates capability of suggested strategy.
Frequency and polarisation selective surface for sub‐millimetre wave atmospheric remote sensing
Authors: Chen Zhaoran , Li Yuying , Huang Kaiyan , Zhao Guozhong , Deng Jinshan , Wang Zezhong , Hu Junjie , Yao Xiayuan
Published: October 2023

A novel Frequency and Polarisation Selective Surface (FPSS) is proposed, which separates two adjacent bands with a narrow transition zone by the staggered separation scheme and is suitable for atmospheric remote sensing. The traditional FSS is transparent in a particular frequency band for both the TE and TM polarisations, while it is opaque in another band for both orthogonal polarisations. The FPSS is introduced in a new splitting scheme that operates above 300 GHz. The channel 420–430 GHz of the TE polarisation and the channel 360–400 GHz of the TM polarisation transmit in the FPSS. In contrast, the band 360–400 GHz of the TE polarisation and the channel 420–430 GHz of the TM polarisation are reflected. The water vapour and the oxygen profiles are detected by the 380 GHz band and the 425 GHz band, respectively. The insertion loss is lower than 1 dB, and the reflection band rejection is superior to 10 dB in the experiment, which determine the sensitivities of the bright temperature by 1.5 (RMS K). The scattered wave of the FPSS is calculated through the far field pattern, the maximum of which is about 5%. The side effect of the scattered wave is able to be ignored in the optical path.
Radar active deception jamming recognition based on Siamese squeeze wavelet attention network
Authors: Wu Zhenhua , Wang Tengxin , Cao Yice , Zhang Man , Yang Lixia
Published: October 2023

Active deception jamming recognition has gained significant attention as a crucial aspect of modern electronic warfare, and a large quantity of jamming recognition methods based on either artificial or deep learning methods have been proposed to date. In actual complex battlefields, the abundant deceptive jamming signals are extremely difficult to obtain and the deceptive jamming signals leveraged by the adversarial jammers are often significantly influenced by noise. To address these challenges a Siamese squeeze wavelet attention network (SSWAN) for radar active deception jamming recognition method is proposed. By constructing a wavelet attention module (WAM), the fine‐grained time‐frequency texture features of echo and jamming signals are preferably extracted even under prohibitively strong noise scenarios. Specifically, the Siamese structure is employed as the main backbone network to measure the similarity between jamming signals and make full use of the training samples; besides, the squeeze learning module is embedded to maintain lightweight and prevent overfitting. Experimental results demonstrate that at a jamming‐to‐noise ratio (JNR) of −8 dB, the proposed method achieves recognition accuracies above 96.3% for 6‐class and multi‐class combinational active deceptive jamming types. Overall, compared to mainstream deep networks, the proposed method exhibits superior advantages in lower JNR ratio and small samples of actual battlefield scenarios.
Bottom-up dust nucleation theory in oxygen-rich evolved stars
Authors: Gobrecht David , Hashemi Seyyed Rasoul , Plane John Maurice Campbell , Bromley Stefan Thomas , Nyman Gunnar , Decin Leen
Published: October 2023

Context. Spinel (MgAl2O4) and krotite (CaAl2O4) are alternative candidates to alumina (Al2O3) as primary dust condensates in the atmospheres of oxygen-rich evolved stars. Moreover, spinel was proposed as a potential carrier of the circumstellar 13 μm feature. However, the formation of nucleating spinel clusters is challenging; in particular, the inclusion of Mg constitutes a kinetic bottleneck.

Aims. We aim to understand the initial steps of cosmic dust formation (i.e. nucleation) in oxygen-rich environments using a quantum-chemical bottom-up approach.

Methods. Starting with an elemental gas-phase composition, we constructed a detailed chemical-kinetic network that describes the formation and destruction of magnesium-, calcium-, and aluminium-bearing molecules as well as the smallest dust-forming (MgAl2O4)1 and (CaAl2O4)1 monomer clusters. Different formation scenarios with exothermic pathways were explored, including the alumina (Al2O3) cluster chemistry studied in Paper I of this series. The resulting extensive network was applied to two model stars, a semi-regular variable and a Mira-type star, and to different circumstellar gas trajectories, including a non-pulsating outflow and a pulsating model. We employed global optimisation techniques to find the most favourable (MgAl2O4)n, (CaAl2O4)n, and mixed (MgxCa(1−x)Al2O4)n isomers, with n = 1–7 and x∈[0..1], and we used high level quantum-chemical methods to determine their potential energies. The growth of larger clusters with n = 2–7 is described by the temperature-dependent Gibbs free energies.

Results. In the considered stellar outflow models, spinel clusters do not form in significant amounts. However, we find that in the Mira-type non-pulsating model CaAl2O3(OH)2, a hydroxylated form of the calcium aluminate krotite monomer forms at abundances as large as 2 × 10−8 at 3 stellar radii, corresponding to a dust-to-gas mass ratio of 1.5 × 10−6. Moreover, we present global minimum (GM) candidates for (MgAl2O4)n and (CaAl2O4)n, where n = 1–7. For cluster sizes n = 3–7, we find new, hitherto unreported GM candidates. All spinel GM candidates found are energetically more favourable than their corresponding magnesium-rich silicate clusters with an olivine stoichiometry, namely (Mg2SiO4)n. Moreover, calcium aluminate clusters, (CaAl2O4)n, are more favourable than their Mg-rich counterparts; the latter show a gradual enhancement in stability when Mg atoms are substituted step by step with Ca.

Conclusions. Alumina clusters with a dust-to-gas mass ratio of the order of 10−4 remain the favoured seed particle candidate in our physico-chemical models. However, CaAl2O4 could contribute to stellar dust formation and the mass-loss process. In contrast, the formation of MgAl2O4 is negligible due to the low reactivity of the Mg atom.
Trend of alternative and renewable energy source use in chosen EU countries
Authors: Culkova Katarina , Tausova Marcela , Taus Peter
Published: October 2023

Currently, one of the most discussed topics is the development of alternative energy sources. The assumption is that the trend in the use of alternative energy sources will continue and will increase every year. The aim of the book chapter is to evaluate the development trend in the use of renewable energy sources in selected countries. The book chapter describes the current situation in the use of renewable energy sources in the world, as well as in the selected countries. We decided to describe and analyze in more detail the use of renewable energy sources such as the wind, solar, water and geothermal energy in countries within Europe such as Italy, Germany and Austria. At the end, there is a comparison of selected indicators with reference to reserves in their use. The results show the share of renewable energy sources has increased; however, it is still necessary to meet the targets in the area of reducing emissions and to increase the production of electricity from renewable energy sources. The results can be used to meet new challenges for the functioning of the energy systems of the European Union, so that European Union could become a world leader in renewable energy sources.
Possibilities of managing electricity consumption through the application of time-classified tariffs
Authors: Kаdirov Kamoliddin , Muratov Khakim , Kushev Аlijon
Published: October 2023

This manuscript is devoted to the issue of smoothing the load schedule of enterprises in “peak” periods in return for using the results of energy audits and applying a system of time-classified tariffs. Considering the mentioned issue above, using the results of the energy inspection and using the system of time-classified tariffs will create an opportunity to achieve smoothing the load schedule of the electric power system during “peak” periods. The use of the time-classified tariff system by consumers will reduce the loading period of the electric power system and change its regimes.
Energy parameters of a hybrid counter-rotor hydraulic unit operating on the basis of solar and hydraulic energy
Authors: Bozarov Oybek , Aliyev Rayimjon , Kodirov Dilshod , Usarov Hamidillo
Published: October 2023

This article analyzes the prospects for using a combined hybrid solar photovoltaic and hydroelectric device and presents their characteristics and energy parameters. In particular, since the hydroelectric device consists of a counter-rotor hydraulic unit, the functional relationship between the dynamic parameters of the reactive and active impellers and the efficiency of the hydraulic unit was investigated. Based on the obtained graphs and analytical expressions, the relationship between the energy parameters of the jet nozzle hydraulic turbine and the design parameters of the hydraulic unit was analyzed.
A priori data on pre-sowing treatment and primary experiments on electric heating of onion seeds
Authors: Denmukhammadiev Aktam , Pardaev Abror , Sobirov Erkin
Published: October 2023

Currently, Uzbekistan is among the twenty most advanced countries in the cultivation of onions. The onion plant was interpreted as a symbol of life in ancient Greek mythologies. Onion is one of the most widely consumed foods in the world due to its essential health and preventive properties, as one of the most essential fruits in the kitchen in the daily diet. The article studies the methods of processing onions before planting based on an analysis of the countries of the world. The results of studies of the influence of various electrophysical parameters on onion seeds are presented analytically. The effective influence of the electric field strength on the health of seeds is explained. The authors also referred to the results and methods of scientific research conducted at NRU “TIIAME” and analyzed the electrical and mechanical properties of onion seeds based on specific experiments. In particular, we analyzed the mass of 1000 seeds, the filling factor of the cubic container, and the initial (primary) results of determining the electrical and thermal conductivity of soaked seeds. The article also provides information on the impact of alternating electric current on onion seeds, developed special electrodes for determining electrical resistance, and a methodology for conducting research experiments. An electrical circuit is presented that ensures the completeness of seed treatment. There are also materials on the positive effect of “electrically activated” water on the additional health of soaked onion seeds. It is shown that the necessary conditions have been created for the process of automated intelligent control of the temperature of soaked onion seeds.
Development of circuit solutions for a wind turbine on the basis of integrated membrane technologies for steam-gas thermal power plants
Authors: Mukhtarov Farrukh , Yarashev Siroj , Akhmedov Akhmad , Usmonov Nizomjon
Published: October 2023

Currently, one of the most promising and effective ways to ensure the necessary quality indicators of desalinated water is the use of devices based on membrane separation technology. At the same time, of great interest are the schemes of water treatment plant, composed only of membrane modules of various purposes: ultrafiltration, reverse osmosis, electrodeionization. The advantages of membrane technology are due to low reagent consumption, easy operation, compact equipment and small amount of highly mineralized wastewater. The increased attractiveness of membrane technologies (especially in recent years) is due to the increase in the prices of reagents, ionites, primary water and also to the tightening of the standards for saline effluent. Thus, the aim of this work is to develop scientific and technical approaches to the creation of water treatment plant on the basis of modern membrane technologies for steam-gas thermal power plant and to develop approaches to design, specialized water treatment plant for humidifying dry air-cooling fan cooling cooling systems.
Calculation of the drying process of dietary materials in solar dryers
Authors: Dadaev Gani , Sultanova Shakhnoza , Safarov Jasur , Mukhiddinov Qobiljon
Published: October 2023

The study introduces a systematic approach to mathematically and computationally model the intricate dynamics inherent in solar storage dryers. A notable contribution of this research lies in the establishment of a methodology for creating mathematical and computer models tailored specifically for solar storage dryers. By devising a structured framework for such modeling, the study endeavors to enhance the understanding of the drying process and its intricacies within the context of herbaceous dietary materials. Through this innovative approach, researchers seek to bridge the gap between theoretical insights and practical applications in the field of solar drying. The developed technique holds the potential to not only deepen our comprehension of drying processes but also pave the way for optimized drying strategies in the context of herbaceous dietary materials. This pioneering effort underscores the role of scientific inquiry in advancing sustainable and efficient practices within the realm of food processing and preservation.Empirical values of drying rate constants and their changes with time are shown. Empirical coefficients Ku1= 5.3956 1/day; ku2= 0.0148 1/day; kw1=0.9858; Kw2=-7.2359. Correlation coefficient matrices, showing the relationship between the drying rate constant and the main environmental factors, indicate that the relationship between the drying rate constant and temperature is non-linear. Approximation of the kinetic curves based on the dynamic mass transfer equation and the proposed empirical dependences of the drying rate constants on temperature has been carried out.
Study on main characteristics of HANWHA solar panels
Authors: Zikrillayev Khayrulla , Sodiqov Timur
Published: October 2023

In this article a Korean-made HANWHA solar panel is considered. Scientific research has been carried out in the first photovoltaic plant since this type of solar panels was installed at this plant. The scientific research based on the measurement, observation and monitoring methods were carried out in October 2022. It turned out that the characteristics of this solar panels are acceptable and can be used in the natural climate conditions of our country. But, in recent years the parameters of the characteristics of this panel have decreased. The average short circuit current value of this panel during the study was 3.5 Amps, which is about 60.18 % less than the nameplate value and the average power on the first and sixth day of the study was 99.60 and 91 Watt respectively, which differ by 8.63 %. After that the authors suggest that is necessary to increase the parameters of characteristics of this panels by applying new cleaning system.
Utilization of Solar Energy for Water Desalination and Purification Using Solar Concentrator
Authors: Navitski Pavel , Izzatillaev Jurabek , Al Dor Ali Al Taleb , Esley Ivan Samuel , Merheb Jonathan , Oliveira Lucas , Sallam Khaled A.
Published: October 2023

This paper focuses on a a solar energy-based project aimed at water desalination and purification. The project's objective is to establish an economically viable and sustainable approach to water heating and desalination, offering benefits to global communities. The project team has devised a solar heating system utilizing a Fresnel array-inspired setup, intended to complement a desalination system employing membrane distillation, which necessitates water heating. The primary focus has been on designing an efficient solar receiver to absorb solar energy for water heating. Moreover, the team has developed equations for concentrator mirror angles across various days, generating charts indicating optimal mirror angles and spacing between mirror rows for different solar times. Project outcomes involve applying heat transfer loss theory via conduction across individual receiver layers, conducting experiments to assess coating efficiency and receiver performance. The team successfully assembled the system with four parallel mirror rows, spaced at 1.5 feet intervals to minimize shadow casting. The solar receiver features two glass tubes, air gaps held by 3D-printed end caps, and an internal mesh turbulator to enhance heat transfer through flow turbulence. The ultimate objective was to heat water sufficiently for membrane distillation (around 40°-70°C). Experimental testing on a windy day with clouds resulted in a final water temperature of 38°C after 3 hours. Receiver efficiency, calculated by comparing solar energy incident on the pipe to energy transferred to water, was 17.5%. While not within the desired range, these promising results, considering surrounding conditions, deem the project successful in creating an efficient heating system for membrane distillation. Recommendations and improvements are possible, confirming the project as a successful proof of concept.
Study on thermal physical detail of gas block wall structure without single source
Authors: Matniyazov Bakdurdi , Aliyev Mashrab , Sagatov Bakhodir , Ziyaviddinov Dilshod
Published: October 2023

This article presents the results of theoretical and experimental studies carried out at the physical heat level in a sample of an outer wall with a small block of a non-code gas block in order to improve the energy efficiency of the outer walls of newly built residential and public buildings. As a result of the studies, the overall thermal conductivity resistance of the outer wall consisting of a non-code small block block, the thermal conductivity coefficient of the wall layers, the temperature flow passing through the wall, the temperature in the wall layers and the heat resistance of the wall for the summer season were revealed. The theoretical thermophysical studies carried out are comparable to experimental studies on the wall model, recommendations have been developed to improve the energy efficiency of the external walls of buildings under construction on the basis of modern projects.
The concept of improving the performance indicators of gas-cylinder vehicles
Authors: Bazarov Baxtiyor , Axmatjanov Ravshanjon , Tojiyev Jamshid , Azimov Akmal
Published: October 2023

This article presents the analysis of operational and environmental indicators of gas cylinder vehicles, their prospects and optimal installation of gas cylinder equipment. In order to improve the operational performance of gas cylinder gas-cylinder vehicles and ensure their environmental safety, the method of choosing gas cylinder equipment according to the technical specifications of the vehicle and setting the appropriate program settings in the optimal state is shown.
Study on differential transformer displacement sensors
Authors: Amirov Sulton , Sulliev Absaid , Sharapov Shukhrat
Published: October 2023

This paper studies magnetic circuits of known and developed differential transformer sensors of large linear motion, which refer to circuits with special structure of magnetic resistance parameters distribution of long ferromagnetic cores and magnetic capacitance between them. It is shown that in the known sensor the distribution of the working magnetic fluxes along the length of the ferromagnetic cores has a nonlinear character, as a result of which the dependence between the output signal in the form of the electromotive force and the input linear motion of the sensor also has a nonlinear character. It was found that by selecting the law of changing the working gap between the middle and inner cores along the length of displacement of the moving measuring winding by making the middle concentric core in the form of a paraboloid of rotation, a linear distribution of the working magnetic flows along the length of the ferromagnetic cores and linearity of the transformation characteristic of the differential transformer sensor of large linear displacements are achieved.
Study on hydraulic pressures in the roll squeezing process
Authors: Annaev Nuriddin , Rasulev Akmal
Published: October 2023

The results of the study of hydraulic phenomenon in the of roller squeezing process. Mathematical models of regularities of changes in filtration rates are found. Based on the analysis of the graphs obtained, the hydraulic pressure distributions are approximated by empirical formulas. Formulas are derived to determine the maximum value of hydraulic pressure and the angle at which this maximum is reached. A formula for calculating the part of the external pressure acting on the liquid is defined.
Hybrid Beam-Column Connection of Precast Concrete Structures: A Review
Authors: Septiarsilia Yanisfa , Iranata Data , Suswanto Budi
Published: October 2023

The use of precast concrete materials as structural elements has become common practice. Precast concrete material offers various advantages over cast in place concrete, including energy-saving, pollution reduction, increased labor productivity, high material durability, reduced formwork and scaffolding usage, faster construction, and the ability to carry out construction in any weather conditions. However, there are some disadvantages in assembling precast elements, particularly in connection areas, which serve as the main structure of a building. Several studies have been conducted to develop connection types for precast concrete. Some of these include dry connections and wet connections, each with their own advantages and disadvantages. To mitigate the weakness of both connection types, many studies are currently focusing on developing a combination of dry and wet connections known as Hybrid Connections. Various developments have been made in the Hybrid connection system.
Isolation and comparative study of various polymorphic forms of inulin
Authors: Rakhmonberdiev Gappar , Ibragimova Komila , Tilakov Jasur , Khusenov Arslon
Published: October 2023

Various forms of inulin, differing in structure and solubility in water, have been isolated and identified. A comparative reaction of periodate oxidation of α-, β- and γ-inulin was carried out. It was determined that the highest oxidation level and the rate of formation of aldehyde groups among the polymorphic forms of the polysaccharide are characteristic of α-inulin. Different forms of inulin, displaying variations in structure and solubility in water, have been successfully isolated and identified. To gain insights into their chemical properties, a comparative study involving periodate oxidation was conducted on α-, β-, and γ-inulin. The results of the study revealed that α-inulin exhibited the highest level of oxidation and the fastest rate of aldehyde group formation among the various polymorphic forms of the polysaccharide. This finding suggests that α-inulin possesses unique chemical reactivity and characteristics compared to the other forms studied. The investigation into the periodate oxidation of inulin polymorphic forms provides valuable information on their respective chemical profiles, aiding in the understanding of their diverse behaviors and potential applications in various fields. This research contributes to the broader knowledge of inulin's properties and may pave the way for its targeted use in specific applications based on its distinctive characteristics.
Study on Interplay of tension, deformation, and ore formation
Authors: Janibekov Bobir , Turapov Mirali , Tulyaganova Nargiza , Zokirov Otabek , Abdurasulov Dilfuza
Published: October 2023

This study undertakes an in-depth exploration of the intricate relationship between gold mineralization in the Tamdytau area within Central Kyzylkum and the underlying tectonic tension and deformation processes. Additionally, the research delves into the interconnection between occurrences of gold ore deposits in Western Uzbekistan and the prevailing regional fault systems. Through thorough investigation, the study unveils compelling insights. The findings demonstrate that a substantial portion, approximately 34%, of the gold ore deposits in the region are geographically situated within zones closely aligned with regional ore-controlling faults that exhibit a predominant northwestern strike. This correlation underscores the significance of these structural features in influencing the distribution of gold mineralization. Furthermore, a detailed analysis of gold ore distribution within the Tamdytau region discloses a noteworthy trend: over 80% of the ore occurrences are strategically located within areas characterized by relatively low shear stress values and stress neutralization conditions. This observation highlights the crucial connection between the geological stress environment and the formation of gold-rich mineralization. These revelations underscore the profound role played by tectonic processes, particularly tension and deformation, in shaping the presence of gold mineralization within the study area. The intricate interplay between geological factors and mineralization patterns has far-reaching implications for the understanding of gold deposition mechanisms and the potential for uncovering valuable resources within this region.
Synthesis of 1-nicotinoylo-3-(meta-nitrophenyl)- thiourea derivatives with anti-inflammatory activity
Authors: Makhsumov Abduhamid , Holboyev Yusubjon , Valeeva Nailya , Ismailov Boburbek , Askarov Ibragim
Published: October 2023

Thiourea derivatives are used in many industries: medicine, agriculture, engineering, rubber industry, organic synthesis. On their basis, various preparations for the needs of the national economy were obtained. The latest studies of thiourea derivatives, carried out at the present time, are prompted not only by theoretical, but also by practical needs. From this point of view, thiourea derivatives are of undoubted interest in substances with different biological activities. They are widely used in agriculture and have been used as herbicides, fungicides, insecticides, bactericides, dyes, growth stimulants, etc. Of particular interest is the use of these compounds in medicine as antitumor, antiviral, anti-inflammatory, antiarrhythmic, vasodilator and other drugs. Today, most of the derivatives of thiourea, urea, the search for new highly effective low-toxic biologically active compounds based on them is constantly ongoing, as can be judged by the large number of publications in the world scientific and patent literature. This article proposes a simple and convenient method for the preparation of 1-nicotinoyl-3-(m-nitrophenyl)-thioureas based on heterocyclic thioisocyanate with nitroaniline in a dimethylformamide medium, in rather high yields. And also studied the anti-inflammatory activity of the synthesized drug.
Modeling the extraction process of pomelo (citrus maxima (burm.) Merr.) Peel essential oil by steam distillation on a production scale (500kg/batch)
Authors: Thien Hien Tran , Thi Tuu Tran , Long Huynh Bao , Thi Ngoc Minh Ly
Published: October 2023

The development of larger-scale extraction processes depends on process kinetics. A production scale of around 500 kg/batch was used in this study to experimentally extract pomelo essential oil by steam distillation. In this study, three models including Model of simultaneous washing and diffusion, Model of instantaneous washing followed by diffusion, and Model of diffusion without washing are considered for evaluation. The most appropriate kinetic model kinetics were chosen using the coefficient of determination (R2) and percentage of variance (%q). The findings demonstrate that the analyzed model of concurrent washing and diffusion suited the experimental data. The results show that in this model, the value of R2 = 0.99795 and q = 0.89285 ± 0.0061, which has the highest value of the three models. The extraction process through this production system was successfully described using a kinetic model, which gave information on the extraction process.
Study on the biochemical indicators of carrot varieties and their scientific and practical importance in the preparation of juice in industry
Authors: Nematova Dildora , Merganov Avazkhan
Published: October 2023

In this article, agrobiological characteristics of local and foreign carrot varieties, their chemical composition, the method and recipes of juice preparation, the importance of homogenized and non-homogenized methods in juice extraction, the determination of tannin in the raw materials using a 3% iron (III) chloride solution, and its industrial importance in the preparation of various juices, information on the determination of total carbohydrate and acid content of juice using refractometer and saccharometer and pH meter equipment is given. Also, scientific and practical results and conclusions on the technological scheme and technology of preparation of “Parkhezbop”, “Popular”, “For children” with addition of special ingredients (ginger, natural honey, lemon juice) are described.
The use of a pulse-expansion module to increase the efficiency of natural feeding of fish by flying insects on artificial ponds
Authors: Ibragimov Matkarim , Kushnazarov Firdavs , Kushnazarov Farrukh
Published: October 2023

The article deals with the problems of providing feed in artificial ponds and fish farms, increasing the proportion of live feed in the fish diet due to flying insects of the base of internal artificial reservoirs. A review of equipment for feeding fish with flying mosquitoes and insects, in which different color stimuli, a fan and PWM are used to attract them, is carried out. The use of this electrical equipment leads to an increase in the productivity of artificial ponds and a reduction in the cost of artificial fish feed. UV LED strip. Thanks to RGB LEDs, the regulation of the chromaticity of their radiation is possible in a wide range by changing the currents passing through R-, G-, B-crystals by specialized PWM drivers of LEDs. The ambient air temperature is controlled by a digital temperature sensor.
Mapping groundwater vulnerability using drastic method
Authors: Nurfahasdi Meutia , Yofita Zega Agnes , Silalahi Agree Manganju Evannels , Singh Dally Raj , Babayev Aziz , Aitova Shakhlo
Published: October 2023

Preventive management and protection of groundwater were to create a groundwater vulnerability map. This map provided information distribution on the level of vulnerability to groundwater contamination in an area. The impact made considered in making regional decisions to create a sustainable development framework. The DRASTIC method is an instrument for evaluating the vulnerability of groundwater pollution. The DRASTIC methods can use evaluate vulnerabilities of groundwater contamination which seven parameters: the depth of the groundwater table (D), rainPL (R), aquifer media (A), soil texture (S), topography (T), the influence of unsaturated zones (I), and hydraulic conductivity (C). The additional parameter is the use of land resulting from vulnerability. The parameter data will be poured into a map using ArcGIS and analyzed using the DRASTIC rating index. Eight attributes are included in the modified DRASTIC model, including hydraulic conductivity of the aquifer, topography, impact of the vadose zone, depth to water table, net recharge, aquifer media, soil media, and aquifer media. In a GIS system, these layers were combined using the Raster Calculator tool. The modelx was further validated using fifteen groundwater composite samples that were also gathered. Based on the results of the analysis, groundwater vulnerability in Terjun’s landfill from the five parameters, the value of the DRASCTIC index is 137 which indicates the vulnerability of groundwater is at medium/moderate. Aquifers next to floodplain areas are very sensitive, whereas those next to terrace areas are less vulnerable, according to the results. The model's findings confirm that the topography, soil media, and aquifer depth indicated the strongest correlations with vulnerability. A positive association between the vulnerability classes and the three groundwater quality measures electrical conductivity was also found during the validation of the final DRASTIC map. Although the levels of contamination at this time are below acceptable bounds, the possibility of additional contamination cannot be completely eliminated and is really rather plausible.
Basis of the improved construction of cotton cleaning equipment
Authors: Ulugmuradov Xamroz , Abbazov Ilkhom , Sharopov Bobir , Muradov Rustam , Gapparova Maxfuza
Published: October 2023

In this article, the analysis of news on the development of the cotton industry in our republic is presented. In addition, based on theoretical studies and analyzes of cleaning processes used in foreign countries, ways to improve the cleaning efficiency of the pile drum, which is the main working organ of cotton cleaning equipment from small impurities. It is based on the need to carry out theoretical calculations of the cleaning surface to improve the cleaning efficiency of the cleaning equipment from small impurities. The results of the theoretical research on calculation of useful surfaces of mesh surfaces based on the calculation of the grid surface located in the lower part of pile barbars used in our Republic and abroad are presented. The need to develop new constructions to increase the use of mesh surfaces to 100% and its calculations were made.
Dust flow motions in dust collection equipment, droplet trajectories and dynamics based on the dust collection chamber’s technical characteristics
Authors: Olimova Nargiz , Alieva Rena , Boboev Sobirjon , Kaldybaev Rashid
Published: October 2023

In the article, the object of research is the mode of operation of the existing and created at the cotton cleaning enterprise dust collection equipment and the degree of change in the amount of dust in the air. The methods of research in which modern methods of determining the parameters and aerodynamics of dust collecting equipment, experiments to determine the degree of pollution of the dust flow and statistical data, the development of a mathematical model of the dust flow in the networks of dust collecting equipment, the trajectory of droplets and dynamics, based on the technical characteristics of dust and gas cleaning chamber are presented.
Theoretical analysis of the movement trajectory of a cotton piece thrown from the pile surface
Authors: Jumaniyazov Qadam , Xolmuratov Oybek , Egamberdiyev Fazliddin , Sharopov Bobur
Published: October 2023

The article contains information about the theoretical analysis of the trajectory of the cotton piece thrown from the surface of the piled drum in the 1XK aggregates available in cotton ginning enterprises. For this, in the recommended cleaning equipment, cotton pieces are dragged through the mesh surface by hanging the drum piles, and the separated impurities fall through the holes of the mesh surface. The piles eject the cotton piece at the appropriate speed. A piece of cotton moves in different trajectories depending on the value of the initial exit velocity and its mass. In this case, it is necessary to determine the impact zone of pile drums located in a row in the zone of cleaning cotton from small impurities. The results of theoretical studies on determining the mathematical model of the movement of cotton pieces along a drum with piles are presented. The problem of determining the impact zone of the next pile drum depending on the movement trajectory after the cotton piece is thrown from the surface of the pile drum in the process of cleaning cotton from small impurities has been solved. The value of the distance between the axis of pile drums was based on the analysis of the obtained trajectories of the movement of cotton particles and the constructed graphical relationships. In addition, the movement of cotton particles along the surface of the piles was analyzed. The results were obtained by analyzing the movement of a piece of cotton under the influence of external forces in order to ensure the transmission of small impurities separated from the mesh surface of the 1XK equipment, which is currently used in production, and the impact of the pile drum on the cotton flow.
Design and methods for calculating the parameters of a machine for cleaning wool from vegetable impurities
Authors: Djuraev Anvar , Elmonov Sirojiddin
Published: October 2023

The article presents an effective scheme and principle of operation of the device, working bodies, drive mechanisms of machines for cleaning wool from vegetable impurities. Theory - experimental studies have obtained the laws of motion of the peg feeder, saw cylinder, impact roller, take-off drum, motor shaft, the main parameters of the device for cleaning wool from plant impurities are substantiated. Based on the results of comparative production tests, recommendations were developed for introducing the developed machine into production.
Diastolic Augmentation with an External Pulsating Device To Treat Cardiogenic Shock
Authors: Trubov Nickolas , Phillips Steven J.
Published: October 2023

An 80 cc stroke volume pulsatile assist device (PAD) was modified and used in place of an intra-aortic balloon for diastolic augmentation when passage of the balloon proved impossible due to aorto-femoral obstruction. The PAD was attached via the usual 10 mm graft sutured end-to-side to the patient’ s left common femoral artery. Systemic heparinization prevented coagulation for 72 hours of PAD support after which time the patient had recovered and was discharged. Metabolic blood pressure was augmented 20–30 mm Hg and CVP reduced from 21 to 9 mm Hg. Pulmonary artery wedge pressure was reduced from 26 to 12 mg Hg and normal urine output was restored. Plasma free hemoglobin ranged from 5–41 mg% and platelet count from 92,000 to 188,000. No complications occurred. Timing was performed in the same manner as in surgery when the PAD is used in conjunction with the pump-oxygenator, and similar precautions were taken. The PAD appears to be an effective alternative counterpulsation in patients suffering from obstructive arteriosclerotic disease precluding the insertion of a balloon catheter.

Intra-aortic balloon pumping is an accepted mode of therapy for treatment of complicated myocardial infarction. 1,2 Some patients who would benefit from intra-aortic balloon pumping cannot have the procedure applied via the femoral artery because of severe arteriosclerotic occlusive disease. This can prevent passage of the balloon or result in complications of insertion. 3–5 A small group of patients in which intra-aortic balloon pump can be applied, develop varying degrees of ischemic neuropathy in the leg in which the balloon was inserted, because of subliminal occlusion by the balloon catheter of the femoral artery, reducing flow through that leg. Here we describe a patient in which an intra-aortic balloon could not be inserted and a Pulsatile Assist Device (PAD®)* was utilized for diastolic augmentation.6,7