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Articles 57631 - 57660 of 294441

Full-Text Articles in Physical Sciences and Mathematics

Induced Spin Textures At 3D Transition Metal–Topological Insulator Interfaces, Slimane Laref, Sumit Ghosh, Evgeny Y. Tsymbal, Aurelien Manchon Jun 2022

Induced Spin Textures At 3D Transition Metal–Topological Insulator Interfaces, Slimane Laref, Sumit Ghosh, Evgeny Y. Tsymbal, Aurelien Manchon

Department of Physics and Astronomy: Faculty Publications

While some of the most elegant applications of topological insulators, such as the quantum anomalous Hall effect, require the preservation of Dirac surface states in the presence of time-reversal symmetry breaking, other phenomena such as spin-charge conversion rather rely on the ability for these surface states to imprint their spin texture on adjacent magnetic layers. In this Rapid Communication, we investigate the spin-momentum locking of the surface states of a wide range of monolayer transition metals (3d-TM) deposited on top of Bi2Se3 topological insulators using first-principles calculations. We find an anticorrelation between the magnetic moment …

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Effect Of Kaolin On Biogenic Coalbed Methane Production And The Response Of Microbial Community, He Huan, Huang Xinying, Huang Zaixing, Zhang Qian, Chen Zihao, Zhao Han, Ren Hengxing, Huang Guanhua Jun 2022

Effect Of Kaolin On Biogenic Coalbed Methane Production And The Response Of Microbial Community, He Huan, Huang Xinying, Huang Zaixing, Zhang Qian, Chen Zihao, Zhao Han, Ren Hengxing, Huang Guanhua

Coal Geology & Exploration

Kaolin is a common inorganic mineral in nature, which can promote the growth and metabolism of microorganisms. There is a large amount of kaolin in coal, however, there are few reports about its bio-gas production of coal. In order to investigate the effect of kaolin on biogas production, the coal obtained from Yulin, Shaanxi Province was taken as the research object, domesticated microorganisms were taken as the research flora, and different qualities of kaolin were added into the culture media to make biological simulation of gas production. The changes of CH4 content, volatile fatty acids (VFAs) concentration, coenzyme F …

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Mesoscopic Law Of Stress And Fracture Evolution Of Coal Seams Hydraulic Fracturing, Li Quangui, Deng Yize, Hu Qianting, Zhang Yuebing, Song Mingyang, Liu Jichuan, Shi Jialin Jun 2022

Mesoscopic Law Of Stress And Fracture Evolution Of Coal Seams Hydraulic Fracturing, Li Quangui, Deng Yize, Hu Qianting, Zhang Yuebing, Song Mingyang, Liu Jichuan, Shi Jialin

Coal Geology & Exploration

Hydraulic fracturing is a technology to increase coal seam permeability, and its stress evolution characteristics and the judgment of fracture morphology and propagation range are particularly important. In this paper, based on directional fracturing, a fluid-structure coupling model of hydraulic fracturing is established by using the discrete element numerical method. The effects of fracturing flow, Poisson’s ratio, natural fracture density on stress evolution and fracture evolution, and their mesoscopic laws are investigated by means of the stress path and crack hot spot diagram. The results show that the stress evolution direction and the final stress path curve shape are obviously …

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Influence Of Fracture Types Of Main Roof On The Stability Of Surrounding Rock Of The Gob-Side Coal-Rock Roadway In Inclined Coal Seams And Its Engineering Application, Gao Lin, Liu Pengze, Zhang Pandong, Wu Guiyi, Kang Xiangtao Jun 2022

Influence Of Fracture Types Of Main Roof On The Stability Of Surrounding Rock Of The Gob-Side Coal-Rock Roadway In Inclined Coal Seams And Its Engineering Application, Gao Lin, Liu Pengze, Zhang Pandong, Wu Guiyi, Kang Xiangtao

Coal Geology & Exploration

Due to the asymmetry and heterogeneity of surrounding rock structure, the surrounding rock of the gob-side coal-rock roadway in inclined coal seams presents more serious deformation and failure under the influence of driving and mining. To reveal the influence of different main roof fracture types on the stability of surrounding rock of the gob-side coal-rock roadway in inclined coal seams, the deformation characteristics of surrounding rock under four main roof fracture types of this kind of roadway are studied by numerical simulation. The results show that the influence degree from highest to lowest of the position of the fracture line …

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Research On Dynamic Response Characteristics Of Typical Ground Fissure Sites In Hebei Plain, Cui Siying, Deng Yahong, Cao Ge, Yu Shuangrui, Mu Huandong, Li Yanjie Jun 2022

Research On Dynamic Response Characteristics Of Typical Ground Fissure Sites In Hebei Plain, Cui Siying, Deng Yahong, Cao Ge, Yu Shuangrui, Mu Huandong, Li Yanjie

Coal Geology & Exploration

Ground fissures in the Hebei Plain are widely distributed and cause severe disasters, seriously impacting local engineering construction and people’s life. The research on ground fissures in the Hebei Plain focuses mainly on the development characteristics, genesis mechanism, and distribution. However, there is little research on the dynamic characteristics of the site in this area. In order to study the influence of ground fissures on the dynamic response of the site in the Hebei Plain, this study conducted microtremor testing on typical earth fissures caused by tectonics, earthquakes, and ancient rivers. It determined the dynamic response characteristics of earth fissure …

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Influence Of Pipeline Crossing On Riverbed Scouring Depth Of Coal Measure Soil, Wang Xinlong, Sun Pinghe, Zhao Mingzhe, Wang Jingyuan, Xing Shikuan Jun 2022

Influence Of Pipeline Crossing On Riverbed Scouring Depth Of Coal Measure Soil, Wang Xinlong, Sun Pinghe, Zhao Mingzhe, Wang Jingyuan, Xing Shikuan

Coal Geology & Exploration

For the purpose of studying the influence of pipeline crossing on the riverbed scouring depth of the coal measure soil, different pipeline depths, pipe diameters and scouring velocity were set up to carry out scour simulation tests based on the clay and sandy riverbed model test equipment. The SPSS software was used to perform multiple linear regression analysis on the riverbed scouring depth and the above factors. The results show that the pipeline depth, pipe diameter and scouring velocity are responsible for 71.4% to 80.6% of the change of scour depth. The burial depth significantly and negatively affects the scouring …

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Techniques For Prevention And Control Of Ordovician Limestone Water Disasters Based On Modified Water Inrush Coefficient Method, Li Kai, Li Xiaolong Jun 2022

Techniques For Prevention And Control Of Ordovician Limestone Water Disasters Based On Modified Water Inrush Coefficient Method, Li Kai, Li Xiaolong

Coal Geology & Exploration

There are technical problems in preventing and controlling Ordovician limestone water disasters during mining above ultra-thin aquifuges, such as those of the lower coal group in Weibei Coalfield. At Sangshuping Coal Mine, horizontal directional drilling technology was used to develop water prevention and control ideas of Ordovician limestone top utilization and grouting transformation. Firstly, considering the loss of water resistance in the floor failure zone, the water inrush coefficient method was used to determine the critical thickness of Ordovician limestone top utilization and grouting transformation. The directional drilling exploration was carried out by drilling from the two opposite ends of …

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Optimization Design Of High Loess Slope Based On Combination Of Wide And Narrow Platform：A Case Study Of An Industrial Square In Zichang City, Nan Ning, Li Peng, Su Shengrui, Dong Fu, Ma Chi Jun 2022

Optimization Design Of High Loess Slope Based On Combination Of Wide And Narrow Platform：A Case Study Of An Industrial Square In Zichang City, Nan Ning, Li Peng, Su Shengrui, Dong Fu, Ma Chi

Coal Geology & Exploration

The construction of a coal mine industrial square in a mountainous area or hilly area will face the problem of high slopes. The unreasonable high slope design causes serious waste of land resources, environmental damage and an increase in investment, and also brings huge potential safety risks to the infrastructure. Based on this, with a high slope in a coal mine industrial square in Zichang City of Shaanxi Province as an example, the field investigation, theoretical analysis and numerical simulation were used to investigate the influence of different numbers, positions and widths of wide platforms on the stress, strain field …

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Conical Source Transient Electromagnetic Response Characteristics With Overburden Based On Occam Constrained Inversion, Li Zhe, Yang Haiyan, Yue Jianhua, Liu Zhixin, Jiang Zhihai, Su Benyu, Zhang Hua, Wang Ling, Yang Fujie Jun 2022

Conical Source Transient Electromagnetic Response Characteristics With Overburden Based On Occam Constrained Inversion, Li Zhe, Yang Haiyan, Yue Jianhua, Liu Zhixin, Jiang Zhihai, Su Benyu, Zhang Hua, Wang Ling, Yang Fujie

Coal Geology & Exploration

The overburden thickness and conductivity can affect transient electromagnetic response in shallow subsurface investigation. In order to further verify the overburden detection effect with a conical source device, combining all-time apparent resistivity conversion of transient electromagnetic field, the electromagnetic response characteristics of the underlying strata influenced by the overburden was studied by introducing an Occam inversion with stratum information constraints. The results indicate that electromagnetic response intensity of the target layer is related to the resistivity ratio of the overburden to the target layer. With the overburden resistivity gradually increasing, the resistivity fitting degree between inversed data and real value …

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Q-P Curve Equation Of Geothermal Well Recharge Test In The Urban Area Of Mei County, Western Guanzhong, Shen Xiaolong, Li Hao, Wang Wei, Cheng Zhouying Jun 2022

Q-P Curve Equation Of Geothermal Well Recharge Test In The Urban Area Of Mei County, Western Guanzhong, Shen Xiaolong, Li Hao, Wang Wei, Cheng Zhouying

Coal Geology & Exploration

Clarifying the relationship between recharge pressure (p) and recharge volume (Q) is crucial for regional green and sustainable geothermal development in geothermal well recharge. The preliminary data of well G102 recharge test in Mei County in the western Guanzhong area were optimized, and three sets of data were determined to clarify this relationship. According to the data, the Q-p curve was drawn. Based on the characteristics of five types of curves in the pressurized water test, it was judged that the curves might be parabolic, logarithmic, and hower function. Therefore, three types of curves were drawn, …

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Experimental Study On The Migration And Distribution Law Of Pulverized Coal In Roadway During Coal And Gas Outburst, Zhang Chaolin, Wang Yibo, Wang Enyuan, Zeng Wei, Wang Peizhong Jun 2022

Experimental Study On The Migration And Distribution Law Of Pulverized Coal In Roadway During Coal And Gas Outburst, Zhang Chaolin, Wang Yibo, Wang Enyuan, Zeng Wei, Wang Peizhong

Coal Geology & Exploration

Coal and gas outburst is one of the geological disasters that seriously threaten coal mine safety production, and its main disaster forms are gas suffocation, impact and burial of pulverized coal. In this paper, the coal and gas outburst experiments under different gas pressures were carried out using the self-developed multi-functional test system for coal and gas outburst simulation. The results show that the gas entrains the pulverized coal and sprays into the roadway in a jet shape after the outburst is triggered. The gas expansion energy is under the pressure of 0.35 MPa and the initial acceleration of outburst …

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Cross Wavelet Analysis Between Layered Monitoring Data Of Stratum Deformation And Groundwater Level Regime, Kong Xiangru Jun 2022

Cross Wavelet Analysis Between Layered Monitoring Data Of Stratum Deformation And Groundwater Level Regime, Kong Xiangru

Coal Geology & Exploration

Land subsidence is usually caused by over-exploitation of groundwater, and its occurrence and development have a certain lag relative to the change in groundwater level. Obtaining the accurate lag time of land subsidence has always been an important topic in land subsidence research. Based on the layered monitoring data of the long-time series of land subsidence and groundwater level regime from 2008 to 2018 by Land Subsidence Monitoring Station in Pinggezhuang, Beijing, the lag effect between stratum deformation in layers at different depths and groundwater level regime is analyzed in this paper by adopting methods of Mann Kendall trend test, …

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Research On Interpolation Error Analysis Of Geological Modeling Of Intelligent Working Face, An Lin, Han Baoshan, Li Peng, Dai Zhenhua, Wang Xinmiao Jun 2022

Research On Interpolation Error Analysis Of Geological Modeling Of Intelligent Working Face, An Lin, Han Baoshan, Li Peng, Dai Zhenhua, Wang Xinmiao

Coal Geology & Exploration

Working face modeling generally obtains the actual distribution of the working face through detection methods such as three-dimensional seismic, tunnel and borehole surveys, and then it establishes the corresponding model using interpolation algorithms. During the modeling process, sampling data are the foundation and interpolation is the necessary way to realize the working face model. The interpolation algorithm and the amount of sampled data affect the accuracy of the face model to varying degrees. Quantitative research on the factors affecting the accuracy of the face model will provide important reference value for the optimization of the interpolation algorithm and the amount …

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Table Of Contents, The Editors Jun 2022

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Numerical Simulation Of Gas Production For Multilayer Drainage Coalbed Methane Vertical Wells In Southern Qinshui Basin, Liu Shiqi, Fang Huihuang, Sang Shuxun, Hu Qiujia, Duan Weiying, Jia Huimin, Mao Chonghao Jun 2022

Numerical Simulation Of Gas Production For Multilayer Drainage Coalbed Methane Vertical Wells In Southern Qinshui Basin, Liu Shiqi, Fang Huihuang, Sang Shuxun, Hu Qiujia, Duan Weiying, Jia Huimin, Mao Chonghao

Coal Geology & Exploration

With the development of CBM (coalbed methane) exploitation, multilayer drainage of the CBM well has received wide attention. The production control technology is the key to ensure high and stable gas production of CBM well multilayer drainage. However, the complex geological conditions of multiple coal seams increase the difficulty of production control of multilayer drainage. Numerical simulation technology is an effective method to study the production control technology of CBM well multilayer drainage. The scientific and reliable simulation results can provide a basis for production control. In this study, considering the influence of temperature effect, shrinkage effect of coal matrix, …

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Sequence-Paleogeography And Coal Accumulation Of The Paleogene Hunchun Formation In The Hunchun Basin, Hou Haihai, Li Qiangqiang, Shao Longyi, Fan Xuejie, Liang Guodong, Li Yanan Jun 2022

Sequence-Paleogeography And Coal Accumulation Of The Paleogene Hunchun Formation In The Hunchun Basin, Hou Haihai, Li Qiangqiang, Shao Longyi, Fan Xuejie, Liang Guodong, Li Yanan

Coal Geology & Exploration

The Hunchun Basin is an important coal-bearing region in Jilin Province, northeastern China. The analysis of the sedimentary paleogeography of the Paleogene Hunchun Formation and coal-accumulation law in the sequence framework provides a theoretical basis for future coal and coalbed methane exploration. The lithofacies, sedimentary systems, sequence paleogeography, and coal accumulation characteristics were analyzed based on regional geology, drilling cores and well logging data. The results show five rock types, including gravel, sandstone, siltstone, mudstone, and combustible organic rock, and twelve lithofacies. The Hunchun Formation was divided into three third-order sequences by three sequence interfaces, including the regional unconformity surface, …

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Stress Sensitivity Characteristics Of Deep Coal Reservoirs And Its Influence On Coalbed Methane Productivity, Liu Shunxi, Fan Kunyu, Jin Yi, Yu Zhenfeng, Dong Jiabin, Wang Changzheng Jun 2022

Stress Sensitivity Characteristics Of Deep Coal Reservoirs And Its Influence On Coalbed Methane Productivity, Liu Shunxi, Fan Kunyu, Jin Yi, Yu Zhenfeng, Dong Jiabin, Wang Changzheng

Coal Geology & Exploration

Deep coal reservoirs are in a high in-situ stress environment, and their permeability change characteristics are quite different from those of shallow ones. In order to study the effect of the effective stress on the permeability difference of deep coal reservoirs and the characteristics of stress sensitivity anisotropy, the samples from 1 200 m to 1 700 m of the No.15 coal seam in the Hengling block in the Qinshui Basin are taken as the research objects. The overburden porosity and permeability experiments are used to study the permeability changes of parallel and vertical bedding samples under different effective stress …

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High-Pressure Jet Disturbance Grouting Technology For Water And Sand Inrush In Roadway Tunneling And Its Application, Zhao Baofeng, Zhu Mingcheng, Li Debin Jun 2022

High-Pressure Jet Disturbance Grouting Technology For Water And Sand Inrush In Roadway Tunneling And Its Application, Zhao Baofeng, Zhu Mingcheng, Li Debin

Coal Geology & Exploration

In order to control the water and sand inrush in roadway tunneling under weak consolidated formation conditions, taking water and sand inrush during the No.2 coal seam roadway tunneling in Maiduoshan Coal Mine of Ningdong Coalfield as the research object, the problems of large amount of engineering, long period of surface treatment and high risk of underground treatment were solved. The construction of the blocking body at the water and sand inrush point was completed by using the water-retaining wall construction technology, high-pressure jet disturbance grouting technology, the integration of drilling and grouting technology, and the pressure control and slurry …

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Recognition Of Land Use On Open-Pit Coal Mining Area Based On Deeplabv3+ And Gf-2 High-Resolution Images, Zhang Chengye, Li Feiyue, Li Jun, Xing Jianghe, Yang Jinzhong, Guo Junting, Du Shouhang Jun 2022

Recognition Of Land Use On Open-Pit Coal Mining Area Based On Deeplabv3+ And Gf-2 High-Resolution Images, Zhang Chengye, Li Feiyue, Li Jun, Xing Jianghe, Yang Jinzhong, Guo Junting, Du Shouhang

Coal Geology & Exploration

A highly efficient means is provided by remote sensing and deep learning to keep tracking of land use in open-pit coal mining area. Based on the high–resolution images from the domestic GF-2 satellite, a DeepLabv3+ model was utilized to achieve recognition of land use on open-pit coal mining area. In addition, a comparison was made among Deeplabv3+, U-Net, FCN, Random Forest, Support Vector Machine, and Maximum Likelihood Method. Firstly, samples data from high-resolution images were produced and sensitivity tests were conducted to determine the optimal cutting size and mode of the sample. Then, the deep neural network model (DeepLabv3+) was …

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Typical Characteristics Of Geological Hazards And Ecological Environment Of Coal Base In The Bends Area Of The Yellow River, Shen Yanjun, Yang Bohan, Wang Shuangming, Kou Haibo, Chen Xing, Xu Yali, Han Senlei Jun 2022

Typical Characteristics Of Geological Hazards And Ecological Environment Of Coal Base In The Bends Area Of The Yellow River, Shen Yanjun, Yang Bohan, Wang Shuangming, Kou Haibo, Chen Xing, Xu Yali, Han Senlei

Coal Geology & Exploration

“The ecological protection and high-quality development of the Yellow River Basin” has now been upgraded to a major national strategy. The bends area (the “几” shaped area, also known as the Jiziwan area) is an important part of the Yellow River Basin, and it is also an important gathering area of China’s coal energy. Now the region has six large modern coal bases, coal production accounts for about 40% of the country, in China’s energy security supply security occupies the “ballast” position. However, the region is located in the western arid-semi-arid region, with fragile ecological environment and poor anti-disturbance ability, …

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Risk Assessment Of Floor Water Inrush By Weighted Rank Sum Ratio Based On Combination Weighting, Yao Hui, Yin Shangxian, Xu Wei, Zhang Runqi, Jiang Zhiting Jun 2022

Risk Assessment Of Floor Water Inrush By Weighted Rank Sum Ratio Based On Combination Weighting, Yao Hui, Yin Shangxian, Xu Wei, Zhang Runqi, Jiang Zhiting

Coal Geology & Exploration

Deep mining of the coal seam causes frequent water hazards in the coal mine floor. As the disadvantages of traditional water inrush risk assessment methods, such as single evaluation index and deviation of the evaluation results from reality are gradually revealed, many new assessment methods are emerging. In this paper, Donghuantuo Coal Mine, a North China type coalfield, in Hebei province is taken as the research object. The evaluation factor sets including aquifer capacity, aquifuge capacity, geological conditions and coal seam conditions are selected, and with ten evaluation factors being considered, a floor water inrush risk evaluation index system applicable …

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Transport Mechanism Of Ammonia Nitrogen In The Simulated Gob Area Packed With Coal Gangue, Li Yusong, Lu Yucan, Cao Qiong, Zhao Li, Zhu Kaipeng, Zhang Qing, Yu Hongfei, Zhang Lei Jun 2022

Transport Mechanism Of Ammonia Nitrogen In The Simulated Gob Area Packed With Coal Gangue, Li Yusong, Lu Yucan, Cao Qiong, Zhao Li, Zhu Kaipeng, Zhang Qing, Yu Hongfei, Zhang Lei

Coal Geology & Exploration

In many coal mining areas in western China, waste water produced during coal mining is often dominant in mine water, resulting in high ammonia nitrogen content. The pretreatment of mine water by filling gangue in coal mine gob areas has become an important measure for the resource utilization of mine water and gangue. The research took the coal gangue from Baode Coal Mine of Shenhua Shendong Coal Group Corporation as the filling medium and the ammonia nitrogen in mine water as the research object. Based on CXTFIT2.1, column simulation experiments were carried out to study the migration mechanism of ammonia …

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Modeling Studies Of Gravity Wave Dynamics In Highly Structured Environments: Reflection, Trapping, Instability, Momentum Transport, Secondary Gravity Waves, And Induced Flow Responses, Wenjun Dong, David C. Fritts, Michael P. Hickey, Alan Z. Liu, Thomas S. Lund, Shaodong Zhang, Yanying Yan, Fan Yang Jun 2022

Modeling Studies Of Gravity Wave Dynamics In Highly Structured Environments: Reflection, Trapping, Instability, Momentum Transport, Secondary Gravity Waves, And Induced Flow Responses, Wenjun Dong, David C. Fritts, Michael P. Hickey, Alan Z. Liu, Thomas S. Lund, Shaodong Zhang, Yanying Yan, Fan Yang

Publications

A compressible numerical model is applied for three-dimensional (3-D) gravity wave (GW) packets undergoing momentum deposition, self-acceleration (SA), breaking, and secondary GW (SGW) generation in the presence of highly-structured environments enabling thermal and/or Doppler ducts, such as a mesospheric inversion layer (MIL), tidal wind (TW), or combination of MIL and TW. Simulations reveal that ducts can strongly modulate GW dynamics. Responses modeled here include reflection, trapping, suppressed transmission, strong local instabilities, reduced SGW generations, higher altitude SGW responses, and induced large-scale flows. Instabilities that arise in ducts experience strong dissipation after they emerge, while trapped smaller-amplitude and smaller-scale GWs can …

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Data-Driven Analytical Predictive Modeling For Pancreatic Cancer, Financial & Social Systems, Aditya Chakraborty Jun 2022

Data-Driven Analytical Predictive Modeling For Pancreatic Cancer, Financial & Social Systems, Aditya Chakraborty

USF Tampa Graduate Theses and Dissertations

Pancreatic cancer is one of the most deathly disease and becoming an increasingly commoncause of cancer mortality. It continues giving rise to massive challenges to clinicians and cancer researchers. The combined five-year survival rate for pancreatic cancer is extremely low, about 5 to 10 percent, owing to the fact that a large number of the patients are diagnosed at stage IV when the disease has metastasized. Our study investigates if there exists any statistical significant difference between the median survival times and also the survival probabilities of male and female pancreatic cancer patients at different cancer stages, and irrespective of …

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Mentoring Undergraduate Research In Mathematical Modeling, Glenn Ledder Jun 2022

Mentoring Undergraduate Research In Mathematical Modeling, Glenn Ledder

Department of Mathematics: Faculty Publications

In writing about undergraduate research in mathematical modeling, I draw on my 31 years as a mathematics professor at the University of Nebraska–Lincoln, where I mentored students in honors’ theses, REU groups, and research done in a classroom setting, as well as my prior experience. I share my views on the differences between research at the undergraduate and professional levels, offer advice for undergraduate mentoring, provide suggestions for a variety of ways that students can disseminate their research, offer some thoughts on mathematical modeling and how to explain it to undergraduates, and discuss the challenges involved in broadening research participation …

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Sedimentary Characteristics And Associated Carbon And Nutrients Of Overbank Sediments Deposited During The 2018, 2019, And 2020 Floods In Embanked Floodplains Along The Lower Mississippi River Near Natchez, Mississippi, Rachel Kelk Jun 2022

Sedimentary Characteristics And Associated Carbon And Nutrients Of Overbank Sediments Deposited During The 2018, 2019, And 2020 Floods In Embanked Floodplains Along The Lower Mississippi River Near Natchez, Mississippi, Rachel Kelk

Master's Theses

The Lower Mississippi River (LMR) experienced major floods in 2018, 2019, and 2020. Sediment deposition in the embanked floodplains during floods represent important storage and sequestration opportunities for carbon and nutrients from ~40% of the continental USA. This research aims to compare depositional thicknesses, organic matter (OM), carbon (C), nitrogen (N), phosphorous (P) concentrations, and grain sizes in floodplain sediments deposited by the combined 2018-19 floods to the 2020 flood along the LMR near Natchez, Mississippi. Greater depositional thicknesses in 2018-19 are best explained by their combined flood durations; the 2019 flood was the longest in recorded history. Slightly higher …

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Student Self-Grading Form, Brett Whysel Jun 2022

Student Self-Grading Form, Brett Whysel

Open Educational Resources

This is a word document that students use at the beginning, midpoint, and end of a semester to set relevant goals, measure progress towards goals, and self-grade. It is intended to build motivation, metacognition, and accountability. Instructors may use it on its own or to supplement other assessment tools, and improve the accuracy, validity, and fairness of final grades.

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Carbon Nanotube Encapsulated Metal Selenide Nanostructures For Efficient Electrocatalytic Oxygen Evolution Reaction, Harish Singh, Wipula P.R. Liyanage, Manashi Nath Jun 2022

Carbon Nanotube Encapsulated Metal Selenide Nanostructures For Efficient Electrocatalytic Oxygen Evolution Reaction, Harish Singh, Wipula P.R. Liyanage, Manashi Nath

Chemistry Faculty Research & Creative Works

Nickel selenide nanowires were grown inside carbon nanotubes through in situ encapsulation via one-step chemical vapor deposition. These NiSe2@CNT nanohybrids showed excellent electrocatalytic activity for water splitting with a low overpotential of 260 mV at 10 mA cm−2, high current density, and extended stability owing to the synergistic effect between NiSe2 and CNTs.

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Reducing Opioid Use Disorder And Overdose Deaths In The United States: A Dynamic Modeling Analysis, Erin J. Stringfellow, Tse Yang Lim, Keith Humphreys, Catherine Digennero, Celia Stafford, Elizabeth Beaulieu, Jack Homer, Wayne Wakeland, Multiple Additional Authors Jun 2022

Reducing Opioid Use Disorder And Overdose Deaths In The United States: A Dynamic Modeling Analysis, Erin J. Stringfellow, Tse Yang Lim, Keith Humphreys, Catherine Digennero, Celia Stafford, Elizabeth Beaulieu, Jack Homer, Wayne Wakeland, Multiple Additional Authors

Complex Systems Faculty Publications and Presentations

Opioid overdose deaths remain a major public health crisis. We used a system dynamics simulation model of the U.S. opioid-using population age 12 and older to explore the impacts of 11 strategies on the prevalence of opioid use disorder (OUD) and fatal opioid overdoses from 2022 to 2032. These strategies spanned opioid misuse and OUD prevention, buprenorphine capacity, recovery support, and overdose harm reduction. By 2032, three strategies saved the most lives: (i) reducing the risk of opioid overdose involving fentanyl use, which may be achieved through fentanyl-focused harm reduction services; (ii) increasing naloxone distribution to people who use opioids; …

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Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins Jun 2022

Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins

USF Tampa Graduate Theses and Dissertations

The Southwest of the United States is currently in a megadrought phase. Recent studies have shown that three of the most severe droughts of the last two millennia have occurred in the last 120 years, while geo-archaeological evidence suggests there were five megadroughts just from 150 to 950 CE. To try to better understand the causes of the droughts across the Southwest, a 110-cm long ice core was drilled from an ice deposit in a lava tube (Cave 29) from El Malpais National Monument in west-central New Mexico. The δ18O values in the ice core (ranging from −11.78 to −3.54‰) …

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