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Articles 91 - 120 of 1024
Full-Text Articles in Geological Engineering
A Geomatic Appraisal On Restoration Of Tank Cascade Systems In Ambuliyar Watershed, Tamilnadu, Nasir N
A Geomatic Appraisal On Restoration Of Tank Cascade Systems In Ambuliyar Watershed, Tamilnadu, Nasir N
Theses and Dissertations
Tanks and earthen embankments used for water harvesting and storage have been a significant part of India's irrigation system since the 2nd and 3rd centuries. In Tamil Nadu, around 39,202 tanks have storage capacities of around 178.94 million cubic feet. However, they have been impacted by natural and anthropogenic threats such as soil erosion, siltation, inadequate rainfall, and drought. This study aims to determine the current storage capacity of tanks, estimate the loss in storage capacity/volume of silt, estimate the rate of siltation and life of tanks, identify soil erosion-prone zones, and map deteriorating parameters along supply channels.
The study …
Experimental Investigation Of Surfactant Impact On Surfactant-Oil-Brine System For Surfactant Enhanced Oil Recovery, Chananpat Worpattanaluk
Experimental Investigation Of Surfactant Impact On Surfactant-Oil-Brine System For Surfactant Enhanced Oil Recovery, Chananpat Worpattanaluk
Chulalongkorn University Theses and Dissertations (Chula ETD)
Enhanced Oil Recovery (EOR) is a vital technique for improving hydrocarbon extraction efficiency from mature or low-production reservoirs. Among various EOR methods, chemical flooding, particularly surfactant-based EOR, has gained attention due to its ability to reduce interfacial tension (IFT), to alter rock wettability, and to mobilize trapped oil. However, the performance of surfactant systems is highly sensitive to reservoir salinity, temperature, and rock-fluid interactions, leading to surfactant precipitation, adsorption losses, and interfacial tension reduction. Therefore, understanding the effects of salinity, surfactant concentration, and the role of scale inhibitors on the physicochemical stability of surfactant-oil-brine systems is essential for designing robust …
Evaluating Co2 Storage Criteria : Focusing On Thailand's Petroleum Basins For Carbon Storage, Paul Tivere Benjamin
Evaluating Co2 Storage Criteria : Focusing On Thailand's Petroleum Basins For Carbon Storage, Paul Tivere Benjamin
Chulalongkorn University Theses and Dissertations (Chula ETD)
Anthropogenic carbon dioxide (CO2) emissions from large point sources remain central to Thailand’s climate challenge, and geological carbon capture and storage (CCS) is now included in national mitigation plans. However, Thailand still lacks a transparent way to compare candidate saline aquifers and petroleum basins in terms of storage performance, containment, and socio-economic conditions, while allowing for uneven data quality. This thesis develops a Thailand-specific, two-stage framework that combines threshold-based screening with a multi-criteria ranking framework based on the Analytic Hierarchy Process (AHP) and Data Confidence Scores (DCS). Twenty-one criteria in three groups (capacity and injectivity, containment, and socio-economic constraints) were …
Simulation On Hydrogen Production From Mae-Moh Lignite Coal Gasification, Pitatchai Arunwong
Simulation On Hydrogen Production From Mae-Moh Lignite Coal Gasification, Pitatchai Arunwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hydrogen energy has attracted significant attention due to its cleanliness, efficiency, and sustainability. Gasification is considered one of the most promising thermochemical routes to convert coal into high-quality syngas, which can subsequently be utilized for hydrogen production. Mae-Moh lignite, a low-rank coal with low carbon content and high moisture and volatile matter, is selected as the feedstock for this study. This research aims to develop a comprehensive simulation model of a hydrogen production process, integrating gasification, water-gas shift (WGS), acid gas removal, and hydrogen purification using the software simulator. The model predicts hydrogen product gas composition from Mae-Moh lignite under …
Predictive Maintenance In Naval Vessel Propulsion Systems For Enhanced Marine Operations Using A Bigmm-Hmm Framework With Divergence-Based Clustering, Farshid Javadnejad, Hyoshin John Park, Samuel Kovacic, Andres Sousa-Poza
Predictive Maintenance In Naval Vessel Propulsion Systems For Enhanced Marine Operations Using A Bigmm-Hmm Framework With Divergence-Based Clustering, Farshid Javadnejad, Hyoshin John Park, Samuel Kovacic, Andres Sousa-Poza
Engineering Management & Systems Engineering Faculty Publications
This study introduces a BiGMM-HMM Integration Framework designed to improve predictive maintenance strategies for naval vessel propulsion systems, addressing the need for efficient and reliable operation in marine engineering applications. The framework effectively manages multimodal sensor data by leveraging a unique combination of Gaussian Mixture Models (GMMs) and Hidden Markov Models (HMMs) in a bidirectional architecture. It analyses the dynamic interactions between sensors and subsystems. Two preprocessing methods are evaluated: Method 1 focuses on subsystem interactions, employing divergence-based root cause analysis to identify key sensor variables by clustering of sensors and subsystems. In contrast, Method 2 processes the entire dataset …
Estimating Unconfined Compressive Strength (Ucs) Of Rocks From Measurement While Drilling (Mwd) Data, Can Erdem
Estimating Unconfined Compressive Strength (Ucs) Of Rocks From Measurement While Drilling (Mwd) Data, Can Erdem
Dissertations, Master's Theses and Master's Reports
Measurement-while-drilling (MWD) technology enables the real-time monitoring of drilling parameters during the drilling process. MWD data can provide valuable insight into the mechanical behavior of intact rocks and rock masses, which is essential for geotechnical applications such as foundation design and underground construction. The aim of this study is to correlate real-time drilling parameters, recorded using a laboratory-developed MWD system, with the unconfined compressive strength (UCS) of rocks. A custom laboratory MWD system was designed to simultaneously record four key drilling parameters: thrust (axial force, crowd), torque, penetration rate, and rotational speed. The custom-built MWD system was used to continuously …
Iron Ore Tailings Reprocessing By Electrostatic Separation Plus Two Stages Froth Flotation, Vincent Bailey Arohunmolase
Iron Ore Tailings Reprocessing By Electrostatic Separation Plus Two Stages Froth Flotation, Vincent Bailey Arohunmolase
Dissertations, Master's Theses and Master's Reports
The reprocessing of tailings is crucial for recovering valuable iron and reducing the environmental impact associated with tailings disposal. This study investigates the practicality of reprocessing tailings to enhance iron oxide content, combining electrostatic separation with a two-stage froth flotation process using oleic acid (direct flotation) and amine (reverse flotation). The primary goal is to efficiently recover valuable iron from tailings, thereby reducing waste and promoting sustainable resource utilization. The process aims to upgrade the iron oxide content to around 93-99% Fe2O3, making the recovered material suitable for the production of direct-reduced iron.
Electrostatic separation was …
Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones
Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones
Graduate Theses/Dissertations
Karst landscapes are abundant in Missouri, with features such as caves, springs, and sinkholes that form through the dissolution of limestone. Leith Creek is a small stream in Polk County, Missouri fed by two springs and the shallow unconfined Springfield Plateau aquifer, a highly karstified aquifer which is made up of limestone and minor interbedded shale-mudstone units. To determine if Leith Creek is gaining or losing, stream flow, water chemistry and temperature sensors were monitored. Stream flow results required multiple visits to take measurements while temperature sensors required two visits, one to install the dataloggers and another to remove the …
Cognitive Map Generation For Vision And Language Navigation, Alexander Sandoval Mesa
Cognitive Map Generation For Vision And Language Navigation, Alexander Sandoval Mesa
Dissertations and Theses
Visual-Language Navigation (VLN) presents significant challenges for autonomous agents, such as robots and virtual assistants, particularly in complex, dynamic environments where the seamless integration of visual perception and natural language understanding is critical. Traditional VLN systems often struggle with effectively aligning language instructions and visual scene understanding, limiting their adaptability and navigation efficiency.
This thesis proposes a novel Cognitive Map-based framework that addresses these challenges by transforming natural language navigation instructions into structured graph representations. The Cognitive Map consists of nodes representing waypoints, landmarks, decision points, and edges encoding spatial relationships and navigational actions. These maps are generated using Large …
Identifying Potential Risk Areas Close To The Oil And Gas Pipelines Due To Subsidence In Qazvin Plain, Mahmoud Rajabi, Sanaz Vajedian, Ryan Smith, Neil Grigg, Hossein Nahavandchi, Mehdi Goli
Identifying Potential Risk Areas Close To The Oil And Gas Pipelines Due To Subsidence In Qazvin Plain, Mahmoud Rajabi, Sanaz Vajedian, Ryan Smith, Neil Grigg, Hossein Nahavandchi, Mehdi Goli
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Surface displacement caused by natural and anthropogenic activities poses a significant risk to subsurface pipelines, particularly in areas experiencing subsidence. Stress and strain induced by deformation can lead to pipeline buckling and potential vulnerability. This study applies a multidisciplinary approach integrating interferometric synthetic aperture radar (InSAR) deformation analysis, well data, and geological context to assess the risk to oil and gas pipelines in Iran's Qazvin plain. The focus is on evaluating the impact of an unconfined aquifer, which has a lower risk of subsidence compared to a confined aquifer, on pipeline infrastructure. We analyzed multitemporal Sentinel-1 data collected between 2014 …
Integration Of Physics-Informed Neural Networks And Transfer Learning For Rainfall Induced Landslide Forecasting, Shian Cao, Weibing Gong
Integration Of Physics-Informed Neural Networks And Transfer Learning For Rainfall Induced Landslide Forecasting, Shian Cao, Weibing Gong
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Rainfall-induced landslides are a significant geological hazard, causing severe economic losses and casualties. Accurate forecasting of these events is particularly challenging due to the complex interactions of spatial and temporal factors governing slope stability. The Iverson model, which uses the Richards equation to describe water infiltration in unsaturated soils, is a widely adopted framework for analyzing rainfall-induced landslides. However, its reliance on traditional numerical methods limits its scalability and efficiency, particularly for complex boundary conditions and transient behaviors near slope failure. To address these limitations, we propose a physics-informed neural network (PINN) enhanced with transfer learning (TL-PINN) to solve the …
Enhancing Pillar Stability Assessment In Underground Limestone Mines Using Lamodel: Integrating Empirical Strength Equations For Improved Ground Control, Alim Elibol
Graduate Theses, Dissertations, and Problem Reports (ETD)
Underground stone mining accounts for approximately 21% of all underground mining operations in the United States, with more than 2,000 workers employed in this sector as of 2019. Ground control failures, particularly those involving massive pillar collapses and roof falls, pose significant safety hazards, contributing to 40% of fatalities and 15% of lost workdays since 2006. Several massive pillar collapses have occurred in active limestone mines from 2015 to 2021, and a fatal incident was reported in January 2022 in a mine operating within the Loyalhanna formation. Given these risks, accurate stability assessment tools are essential for improving mine safety. …
Applications Of Reservoir Simulation And Machine Learning In Subsurface Energy Systems For Decarbonization, Seyedmohammadmehdi Nassabeh
Applications Of Reservoir Simulation And Machine Learning In Subsurface Energy Systems For Decarbonization, Seyedmohammadmehdi Nassabeh
Theses: Doctorates and Masters
The transition to a low-carbon future necessitates innovative approaches to carbon management and hydrogen storage, particularly in the context of enhanced oil recovery (EOR) from hydrocarbon reservoirs. This study employs advanced analytics and machine learning techniques to optimize carbon management strategies. One key focus of this research is to evaluate the effectiveness of flue gas and CO2 in Water Alternating Gas (WAG) injection within a homogeneous fractured carbonate reservoir characterized by low porosity and permeability. A computational model was developed to depict the flow regime in the reservoir and simulate reservoir fluid behavior using Eclipse (E300) software, various hybrid EOR …
Bаsing Thе Sресifiс Сhаrасtеristiсs Оf Sаlinе Sоils Оn Thе Bаsis Оf Buildings Аnd Struсturеs In Thе Соnditiоns Оf Uzbеkistаn (Аs Аn Еxаmрlе Оf Thе Mirzасhоl Рlаins), Аbdubaki Djalilovich Kауumоv, Murad Kаmbаrоv, Olmos Zafarov, Zukhriddin Muradov, Islom Ilhom Ugli Ro‘Ziyev
Bаsing Thе Sресifiс Сhаrасtеristiсs Оf Sаlinе Sоils Оn Thе Bаsis Оf Buildings Аnd Struсturеs In Thе Соnditiоns Оf Uzbеkistаn (Аs Аn Еxаmрlе Оf Thе Mirzасhоl Рlаins), Аbdubaki Djalilovich Kауumоv, Murad Kаmbаrоv, Olmos Zafarov, Zukhriddin Muradov, Islom Ilhom Ugli Ro‘Ziyev
Technical science and innovation
This article comprehensively examines the physical-mechanical and chemical properties of saline soils and their changes under the influence of moisture, as well as the impact of these changes on the foundations of buildings and structures. The study analyzes the variation of salinity levels over time due to prolonged water exposure and its effects on the stability and safety of structures, highlighting critical issues observed in regions of our country where saline soils are prevalent. Based on engineering-geological and hydrogeological research, solutions to minimize the consequences of salinity, determine soil deformation and strength characteristics, and ensure the safety of structures are …
Development Of An Effective Container Design That Reliably Provides Isolation Of Water Inflow And Elimination Of Well Flooding, Tolib Olimovich Komilov Suffix, Sherali Hallokovich Umedov, Anvarkhoja Akbarkhodjayevich Rakhimov
Development Of An Effective Container Design That Reliably Provides Isolation Of Water Inflow And Elimination Of Well Flooding, Tolib Olimovich Komilov Suffix, Sherali Hallokovich Umedov, Anvarkhoja Akbarkhodjayevich Rakhimov
Technical science and innovation
Currently, the hydrocarbon extraction industry is one of the most high-tech and rapidly developing sectors globally. The primary priority of this industry is to improve the technical and economic indicators of drilling and well operation. A particularly pressing issue is reducing well waterlogging and effectively isolating water flows, which contributes to optimizing hydrocarbon resource development. The introduction of modern equipment into production processes increases the demand for hydrocarbon resources, further complicating the challenges faced by the industry. This article highlights the relevance of applying innovative technologies to address well complications. Specifically, a new technology for isolating water flows and eliminating …
Development Of The Principles Of Forming A Database For Geoinformation Mapping Of Tourism (As An Example Of Bostanlyk District Of Tashkent Region), Lola Xoji-Akbarovna Gulyamova, Risolat Raximjon Qizi Nizomova
Development Of The Principles Of Forming A Database For Geoinformation Mapping Of Tourism (As An Example Of Bostanlyk District Of Tashkent Region), Lola Xoji-Akbarovna Gulyamova, Risolat Raximjon Qizi Nizomova
Technical science and innovation
When creating tourist assessment maps for the purpose of tourist mapping, special attention is paid to determining the criteria for the formation of a database. To assess tourism opportunities in terms of natural conditions, ecology and socio-economic factors, data collection, their characteristics and requirements for them were studied. In order to improve the quality of sources of tourist assessment maps, parables of working with the internet and real-time removable data, creating a map based on social network data were considered. Proposals were made to create, manage and maintain a big data base. The ArcGIS program analyzed the possibilities of describing …
Qualitative Analysis Of The Circuits Of Autonomous Inverters With Shut-Off Valves, Shukhrat Badreddinovich Umarov
Qualitative Analysis Of The Circuits Of Autonomous Inverters With Shut-Off Valves, Shukhrat Badreddinovich Umarov
Technical science and innovation
The article presents the results of a qualitative analysis of circuits of autonomous current and voltage inverters with cut-off valves; the influence of the charge value of the switching capacitor in parallel and series equivalent circuits on the restoration of the switching properties of the thyristors of the inverter power circuit is studied. It is shown that due to the energy periodically accumulated in the inductive elements of the load, the voltage on the switching capacitor in the cut-off state is greater than in a conventional parallel autonomous current inverter. This circumstance ensures an increase in the switching stability of …
Application Of Satellite Interferometry To Tailings Damages To Determine Their Stability, Mukhlisa Khasanovna Rakhimova
Application Of Satellite Interferometry To Tailings Damages To Determine Their Stability, Mukhlisa Khasanovna Rakhimova
Technical science and innovation
In our country and abroad, the construction of special alluvial hydraulic structures - tailings storage facilities - is being carried out on a large scale for storing waste from the mineral enrichment process, the operation of which requires ensuring and observing strict technological control, failure of which leads to serious accidents and even disasters. Tailings dams play a critical role in the mining and metallurgy industry by providing safe storage of production waste. However, their stability and safety are a constant concern. Satellite interferometry (InSAR) is an innovative technology that can effectively monitor deformations and changes in the condition of …
Polyaxial Stress-Dependent Tensorial Permeability Variations Of A Columnar Jointed Rock Mass: Insights From 3d Distinct Element Method, Prasad Pothana, Vamegh Rasouli, Kegang Ling
Polyaxial Stress-Dependent Tensorial Permeability Variations Of A Columnar Jointed Rock Mass: Insights From 3d Distinct Element Method, Prasad Pothana, Vamegh Rasouli, Kegang Ling
Petroleum Engineering Student Publications
Stress-induced permeability changes in geological formations have implications for various geo-engineering applications. Fractures are the predominant fluid flow pathways within tight geological formations such as jointed basaltic rock mass. Three-dimensional permeability variations of a columnar jointed rock mass using the three-dimensional block distinct element method are investigated. First, a permeability tensor is constructed by simulating fluid flow through joint sets using cubic law and determining its principal components through eigenvector analysis. Subsequently, numerical simulations are conducted to gain insights into the impact of principal stresses on joint deformation and fluid flow. Joint deformation is controlled by the joint’s mechanical properties, …
Deciphering Mechanochemical Influences Of Emergent Actomyosin Crosstalk Using Qcm‑D, Emily M. Kerivan, Victoria N. Amari, William B. Weeks, Leigh H. Hardin, Lyle Tobin, Omayma Y. Al Azzam, Dana N. Reinemann
Deciphering Mechanochemical Influences Of Emergent Actomyosin Crosstalk Using Qcm‑D, Emily M. Kerivan, Victoria N. Amari, William B. Weeks, Leigh H. Hardin, Lyle Tobin, Omayma Y. Al Azzam, Dana N. Reinemann
Faculty and Student Publications
Purpose: Cytoskeletal protein ensembles exhibit emergent mechanics where behavior in teams is not necessarily the sum of the components’ single molecule properties. In addition, filaments may act as force sensors that distribute feedback and influence motor protein behavior. To understand the design principles of such emergent mechanics, we developed an approach utilizing QCM-D to measure how actomyosin bundles respond mechanically to environmental variables that alter constituent myosin II motor behavior.
Methods: QCM-D is used for the first time to probe alterations in actin-myosin bundle viscoelasticity due to changes in skeletal myosin II concentration and motor nucleotide state. Actomyosin bundles were …
Interpreting Strain Caused By Transient Well Testing, Soheil Roudini
Interpreting Strain Caused By Transient Well Testing, Soheil Roudini
All Dissertations
Understanding reservoir properties and structure is essential to managing subsurface operations, such as geologic storage of CO2 or production of water, hydrocarbons or heat. Previous work demonstrated the potential of analyzing strain data during transient well tests by estimating hydraulic diffusivity using a type-curve-like approach. The following dissertation aims to pursue this potential by developing and evaluating methods for interpreting strain tensor data to improve subsurface characterization. The research advances the classic, intuitive method of using type-curves to interpret well tests, but it also brings together modern computational methods from machine learning, proxy modeling and Bayesian inversion, and it …
Geochemical Evidence Of Drying During The 4.2 Ka Event In Sediment Cores From The Yucatán Peninsula, Mexico, Derek K. Gibson, Jonathan Obrist-Farner, Alex Correa-Metrio, Alejandra Rodriguez-Abaunza, Carlos Castañeda-Posadas
Geochemical Evidence Of Drying During The 4.2 Ka Event In Sediment Cores From The Yucatán Peninsula, Mexico, Derek K. Gibson, Jonathan Obrist-Farner, Alex Correa-Metrio, Alejandra Rodriguez-Abaunza, Carlos Castañeda-Posadas
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Tropical hydroclimate variability during the Middle and Late Holocene was investigated using geochemical indicators of local-scale precipitation and evaporation preserved in sediment cores from two sites in the Mexican Yucatán Peninsula. Scanning X-Ray fluorescence spectroscopy data show generally decreasing precipitation trends during the Early and Middle Holocene. During the transition between the Middle and Late Holocene, geochemical evidence of reduced watershed erosion and increased evaporation indicate that a centennial-scale drying event impacted the region between 4.3 and 4.0 ka (kilo-anum; thousand years before present). These findings suggest that the 4.2 ka drying event, which has been previously recorded in Europe, …
Characterization Of Non-Gaussianity In The Snow Distributions Of Various Landscapes, Noriaki Ohara, Andrew D. Parsekian, Benjamin M. Jones, Rodrigo C. Rangel, Kenneth M Hinkel, Rui A.P. Perdigão
Characterization Of Non-Gaussianity In The Snow Distributions Of Various Landscapes, Noriaki Ohara, Andrew D. Parsekian, Benjamin M. Jones, Rodrigo C. Rangel, Kenneth M Hinkel, Rui A.P. Perdigão
Michigan Tech Publications
Seasonal snowpack is an important predictor of the water resources available in the following spring and early-summer melt season. Total basin snow water equivalent (SWE) estimation usually requires a form of statistical analysis that is implicitly built upon the Gaussian framework. However, it is important to characterize the non-Gaussian properties of snow distribution for accurate large-scale SWE estimation based on remotely sensed or sparse ground-based observations. This study quantified non-Gaussianity using sample negentropy; the Kullback-Leibler divergence from the Gaussian distribution for field-observed snow depth data from the North Slope, Alaska; and three representative SWE distributions in the western USA from …
Collapse Of Pre-Covid-19 Differences In Performance In Online Vs. In-Person College Science Classes, And Continued Decline In Student Learning, Gregg R. Davidson, Hong Xiao, Kristin Davidson
Collapse Of Pre-Covid-19 Differences In Performance In Online Vs. In-Person College Science Classes, And Continued Decline In Student Learning, Gregg R. Davidson, Hong Xiao, Kristin Davidson
Faculty and Student Publications
Abstract: Studies comparing student outcomes for online vs. in-person classes have reported mixed results, though with a majority finding that lower-performing students, on average, fare worse in online classes, attributed to the lack of built-in structure provided by in-person instruction. The online/in-person outcome disparity was normative for non-major geology classes at the University of Mississippi prior to COVID-19, but the difference disappeared in the years after 2020. Previously distinct trendlines of GPA-based predictions of earned-grade for online and in-person classes merged. Of particular concern, outcomes for in-person classes declined to match pre-COVID-19 online expectations, with lower-GPA students disproportionally impacted. Objective …
Measuring Soil Salinity, Department Of Primary Industries And Regional Development, Western Australia
Measuring Soil Salinity, Department Of Primary Industries And Regional Development, Western Australia
Natural resources factsheets
To make sound decisions on managing saline sites, you need to know the source of salt, how salinisation is occurring, the landscape context, and most importantly, the actual salt concentration of the soil.
The most common 'measures' of salt concentration are actually estimates based on electrical conductivity of a soil and water solution. Soil salt content can be measured in a laboratory by measuring the total dissolved solids in a sample. In the field, salt concentration can also be estimated using electromagnetic induction-based soil sensors.
Topography Of The 410 And 660 Km Discontinuities Beneath The Tibetan Plateau And Adjacent Areas, Zexin Miao, Stephen S. Gao, Muchen Sun, Kelly H. Liu
Topography Of The 410 And 660 Km Discontinuities Beneath The Tibetan Plateau And Adjacent Areas, Zexin Miao, Stephen S. Gao, Muchen Sun, Kelly H. Liu
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
To investigate the three-dimensional spatial distribution of subducted oceanic slab segments and their consequential effect on the thermal and hydrous composition of the mantle transition zone (MTZ) beneath the entire Tibetan Plateau, we conducted a comprehensive analysis of approximately 655,000 P-to-s receiver functions (RFs), obtained from 735 broadband seismic stations. These RFs were utilized to delineate the 410 km (d410) and 660 km (d660) seismic discontinuities, which represent the upper and lower boundaries of the MTZ, respectively. The RFs were grouped within circular bins with a radius of 1 degree and stacked to image the discontinuities. The mean apparent depths …
Spatial And Temporal Variations Of Seismic Azimuthal Anisotropy Following The 2019 Ridgecrest Earthquake Sequence In Southern California, Yan Jia, Stephen S. Gao, Kelly H. Liu
Spatial And Temporal Variations Of Seismic Azimuthal Anisotropy Following The 2019 Ridgecrest Earthquake Sequence In Southern California, Yan Jia, Stephen S. Gao, Kelly H. Liu
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
To investigate the spatial and temporal variations of seismic azimuthal anisotropy in the vicinity of the conjugate fault network activated by the 4 July 2019 (UTC) M6.4 foreshock and the 6 July 2019 M7.1 mainshock in Ridgecrest, California, a total of 1,470 shear wave splitting measurements were obtained from local events recorded by five seismic stations over the period of July 2019 to January 2020. The results suggest a strong asymmetry in anisotropy forming mechanisms across the NW-SE striking Eastern Little Lake Fault, which is the main fault of the area. In the area located to the northeast of the …
Study Of The Physical-Chemical Properties Of Chitosan Synthesized By The Cryogenic Method From Apis Mellifera Bees, Dilnoza Sohibovna Isomitdinova, Gulnora Akmalovna Ikhtiyarova, Jahongir Mustaqim O’G’Li Sharopov
Study Of The Physical-Chemical Properties Of Chitosan Synthesized By The Cryogenic Method From Apis Mellifera Bees, Dilnoza Sohibovna Isomitdinova, Gulnora Akmalovna Ikhtiyarova, Jahongir Mustaqim O’G’Li Sharopov
Technical science and innovation
Chitosan was synthesized from Apis Mellifera dead bees by traditional and cryogenic methods, and the degree of deacetylation, viscosity, and molecular mass of the synthesized sample was studied. Chitosan was synthesized by deacetylation of chitin under cryogenic conditions. NaOH concentration 40%, temperature 90 ± 3 °C, time 120 min. The degree of deacetylation, and molecular mass was determined using an Ubbelode viscometer. DDA was determined by conductometric titration under standard conditions. The degree of deacetylation of Apis Mellifera chitosan was 87%. synthesized by cryogenic method DDA of chitosan was 83% synthesized by traditional method. Conducting the synthesis in liquid nitrogen …
Study Of The Synthesis Mechanism And Some Properties Of Oligomers Based On Epichlorohydrin And Diphenylguanidine, Rovshan Israilovich Ismailov, Normuhamad Edgarov, Alisher Israilovich Ismailov
Study Of The Synthesis Mechanism And Some Properties Of Oligomers Based On Epichlorohydrin And Diphenylguanidine, Rovshan Israilovich Ismailov, Normuhamad Edgarov, Alisher Israilovich Ismailov
Technical science and innovation
In this work, the synthesis and the scheme for obtaining an oligomer based on epiiodhydrin with diphenylguanidine were studied, the proportions of epiiodhydrin in the initial mixture, the yield of oligomers, and the reduced viscosity were studied. The results of spectroscopic and elemental analyzes are obtained, which show that changes in the ratio of monomers have almost no effect on the iodine content in the oligomer. This is apparently due to the fact that epiiodhydrin is much more active in reactions than amino compounds. By studying the degree of conversion on the viscosity of the oligomerization products, the effects on …
Justification Of The Effectiveness Of Software For The Design Of Open-Pit Mining, Tolib Olimovich Komilov, Bobirjon Nabijonovich Ashurov, Ulugbek Bakhtiyorovich Sattarov, Ma’Ruf Ixtiyorovich Karimov
Justification Of The Effectiveness Of Software For The Design Of Open-Pit Mining, Tolib Olimovich Komilov, Bobirjon Nabijonovich Ashurov, Ulugbek Bakhtiyorovich Sattarov, Ma’Ruf Ixtiyorovich Karimov
Technical science and innovation
The article notes that the economic feasibility of implementing a project based on deposits directly affects the economy of the country and the region, as well as the construction of new facilities, the use of the most balanced approaches and design solutions in a complex will allow achieving the set goal of increasing production volumes and bringing the enterprise to a new level of development. In order to achieve the above goals, it has been proven with the implementation of investment projects using software for the design of open-pit mining, it is possible to further develop the region, agriculture with …