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The Estuarine Ecological Knowledge Network Makes Progress: International Project Sites And Potential Ways Forward, Grant S. Mccall, Anthony Akpan, Doru Banaduc, Diego F. Figueroa, Nelson Fontoura, Robert Hitchcock, Sherman Horn, Devashish Kar, Thong Tran Jun 2022

The Estuarine Ecological Knowledge Network Makes Progress: International Project Sites And Potential Ways Forward, Grant S. Mccall, Anthony Akpan, Doru Banaduc, Diego F. Figueroa, Nelson Fontoura, Robert Hitchcock, Sherman Horn, Devashish Kar, Thong Tran

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Estuarine Ecological Knowledge Network (EEKN) brings together scientists and coastal fishing communities in seeking new ways forward for Earth's major river deltas and estuaries, including the Mississippi (United States), Rio Grande (United States), Danube (Romania/Ukraine), Ganges (India/Bangladesh), Niger (Nigeria), and Mekong (Vietnam) river deltas, and the Patos Lagoon (Brazil). Such environments are universally understood as crucial for the biological productivity of oceans and they are home to hundreds of millions of human inhabitants, many of whom directly depend on that marine richness in terms of the operation of their socioeconomic systems. As human-induced climate change and its consequences for …


Draft Final Blacktail Creek Remediation And Contaminated Groundwater Hydraulic Control Site Piezometer Installation And Monitoring Well Repair Plan, Pioneer Technical Services, Inc. Jun 2022

Draft Final Blacktail Creek Remediation And Contaminated Groundwater Hydraulic Control Site Piezometer Installation And Monitoring Well Repair Plan, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


2022 - Draft Final - Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Phase Iii Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc. Jun 2022

2022 - Draft Final - Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Phase Iii Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Iowa Waste Reduction Center Newsletter, June 2022, University Of Northern Iowa. Iowa Waste Reduction Center. Jun 2022

Iowa Waste Reduction Center Newsletter, June 2022, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Contents:

--- Your Guide to Small Business Assistance: Air Permit Applications& Emissions Reporting
--- Mapping of Rural Iowa Food Deserts
--- NoCoast Beer Co. Achieves Iowa Green Brewery Platinum Certification
--- IWRC’s Jennifer Trent to serve on the Des Moines Climate Action & Adaptation Plan Technical Advisory Group (TAG)
--- IWRC Welcomes New Environmental Intern: Sam Lueders
--- Industry News


Evaluating Loblolly Pine Bioenergy Development Potential Using Ahp Integrated Weighted Overlay And Network Optimization In Virginia, Usa, Huynh Truong Gia Nguyen, Erik Lyttek, Pankaj Lal, Taylor Wieczerak, Trang Luong Jun 2022

Evaluating Loblolly Pine Bioenergy Development Potential Using Ahp Integrated Weighted Overlay And Network Optimization In Virginia, Usa, Huynh Truong Gia Nguyen, Erik Lyttek, Pankaj Lal, Taylor Wieczerak, Trang Luong

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Bioenergy is an essential piece of the United States’ (US) energy portfolio. However, questions surrounding bioenergy sourcing and adoption at the producer level remain persistent challenges, hampering proliferation in areas not already available. To establish new industries, individual regions must be evaluated for various bioenergy feedstocks and incorporate elements for environmental, societal, and economic growth. This study assessed the overall potential for loblolly pine (Pinus taeda) in Virginia, US, for domestic bioenergy by utilizing stakeholder preferences for site selection and biomass potential from a regional growth and yield model. Our results show that bioenergy in the state requires widespread planting …


Planning Methodology For Alternative Intersection Design And Selection, Liran Chen May 2022

Planning Methodology For Alternative Intersection Design And Selection, Liran Chen

Dissertations

The recent publication of the 6th Edition of the Highway Capacity Manual included a chapter on Ramp Terminals and Alternative Intersections that introduces various alternative intersection designs and assesses the performance of Median U-turn, Restricted crossing U-turn and Displaced left-turn intersections. Missing from the literature is an alternative intersection selection tool for identifying whether an alternative intersection would be successful under local conditions. With limited information of organized alternative intersection research, most planners must rely heavily on their personal judgement while selecting the most suitable intersection designs. As appealing as alternative intersections are, there is no comprehensive methodology for planners …


Atmospheric Mercury Chemistry: Detection, Kinetics, And Mechanism, Na Mao May 2022

Atmospheric Mercury Chemistry: Detection, Kinetics, And Mechanism, Na Mao

Dissertations

The presence of mercury in the environment is of global concern due to its toxicity. The atmosphere is an important transient reservoir for mercury released by human activities and natural sources. The knowledge of atmospheric mercury chemistry is critical for understanding the global biogeochemical cycle. In the atmosphere, mercury primarily exists in three forms: gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particulate-bound mercury (PBM). Over the last decade, the existing knowledge of mercury cycle has dramatically changed: (1) There has been increasing evidence that current detection methods do not accurately quantify gaseous oxidized mercury and a technique which …


Reactive Iron Mineral Coatings In Redox Transition Zones Of A Site With Historical Contamination: Abiotic Attenuation, Xin Yin May 2022

Reactive Iron Mineral Coatings In Redox Transition Zones Of A Site With Historical Contamination: Abiotic Attenuation, Xin Yin

Dissertations

Reactive iron mineral coatings are found throughout reduction-oxidation (redox) transition zones and play a significant role in contaminant transformation processes. In this study, an 18.3-meter core is collected, subsampled, and preserved under anoxic conditions to maintain its original redox state. Screening analyses are conducted at sampling increments of 5.08 cm in depth for the following: elemental concentrations with X-ray fluorescence (XRF), sediment pH, sediment oxidation-reduction potential (ORP), total volatile organic carbon (TVOC) in the sample headspace, and abundant bacteria (16S rRNA sequencing). Using the Fe and S gradients correlated with microbial data, five RTZs are delineated. To characterize iron mineral …


Integration Of Sustainability Into Higher Education Policies: A Case Study Of The University Of South Florida, Mehmet Z. Apaydin May 2022

Integration Of Sustainability Into Higher Education Policies: A Case Study Of The University Of South Florida, Mehmet Z. Apaydin

USF Tampa Graduate Theses and Dissertations

Sustainability and the United Nations Sustainable Development Goals (SDGs) are not new notions for higher education institutions (HEIs). However, well-organized efforts to make campuses "sustainable" are not common, and the efforts are modest compared to the institutional capabilities. This thesis, a case study of the University of South Florida (USF), was designed to explore how sustainability values and SDGs are incorporated into higher education policies. To accomplish this, the study employed a mixed method design that includes a literature review, an overview of policies and implementations, document content analysis, a program and course inventory, a keyword analysis, and semi-structured interviews. …


Climate Change Impacts And Projections For The Greater Boston Area: Findings Of The Greater Boston Research Advisory Group Report, Ellen Douglas, Paul Kirshen May 2022

Climate Change Impacts And Projections For The Greater Boston Area: Findings Of The Greater Boston Research Advisory Group Report, Ellen Douglas, Paul Kirshen

School for the Environment General Publications

During the writing of the inaugural Boston Research Advisory Group (BRAG) report both NASA and NOAA announced that 2015 was the warmest year on record, beating the previous record set in 2014, by 0.29 °F. Just five years later (during the writing of this report), NASA announced that 2020 had tied 2016 for the warmest year, breaking the previous record by a stunning 1.84 °F, and that the last seven years have been the warmest seven-year period on record.

These observations support the assertion made in the sixth and most recent assessment by the Intergovernmental Panel on Climate Change , …


Where To Invest Project Efforts For Greater Benefit: A Framework Formanagement Performance Mapping With Examples For Potato Seed Health, C. E. Buddenhagen, Y. Xing, J. L. Andrade-Piedra, G. A. Forbes, P. Kromann, I. Navarrete, S. Thomas-Sharma, Robin A. Choudhury, K. F. Andersen Onofre, E. Schulte-Geldermann May 2022

Where To Invest Project Efforts For Greater Benefit: A Framework Formanagement Performance Mapping With Examples For Potato Seed Health, C. E. Buddenhagen, Y. Xing, J. L. Andrade-Piedra, G. A. Forbes, P. Kromann, I. Navarrete, S. Thomas-Sharma, Robin A. Choudhury, K. F. Andersen Onofre, E. Schulte-Geldermann

School of Earth, Environmental, & Marine Sciences Faculty Publications

Policymakers and donors often need to identify the locations where technologies are most likely to have important effects, to increase the benefits from agricultural development or extension efforts. Higher-quality information may help to target the high-benefit locations, but often actions are needed with limited information. The value of information (VOI) in this context is formalized by evaluating the results of decision making guided by a set of specific information compared with the results of acting without considering that information. We present a framework for management performance mapping that includes evaluating the VOI for decision making about geographic priorities in regional …


Comments On The Draft Butte Priority Soils Operable Unit (Bpsou) 2020 Groundwater Compliance And Interpretation Technical Memorandum (Dated May 12, 2022), Nikia Greene May 2022

Comments On The Draft Butte Priority Soils Operable Unit (Bpsou) 2020 Groundwater Compliance And Interpretation Technical Memorandum (Dated May 12, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Damming Sustainability: How Social And Environmental Networks Influence The Construction And Management Of Large Dams In The Amazon Basin, V. Miranda Chase May 2022

Damming Sustainability: How Social And Environmental Networks Influence The Construction And Management Of Large Dams In The Amazon Basin, V. Miranda Chase

Graduate Doctoral Dissertations

,p>Dams are powerful structures that engender a flood of controversies. These projects face great criticism from numerous groups, many of whom succeed in influencing such enterprises. This research is an in-depth study on dam-related social and environmental movements in the Amazon: how they are created and internally organized; how members share information and resources, how they identify alternatives; and how they design strategies and implement agendas. Social movements include, but are not limited to, domestic and international nongovernmental organizations (NGOs), academic researchers, journalists, religious organizations, grassroots associations, and large private foundations. They create formal or informal coalitions and design …


Understanding Environmental Justice Instruction In Higher Education: Activist Epistemic Orientations And A Continuum Of Community Engaged Curricular And Pedagogical Practice, Christopher James Rabe May 2022

Understanding Environmental Justice Instruction In Higher Education: Activist Epistemic Orientations And A Continuum Of Community Engaged Curricular And Pedagogical Practice, Christopher James Rabe

Graduate Doctoral Dissertations

Starting in the early 1980’s, the environmental justice (EJ) movement was critical in drawing much needed attention to how communities of color, low-income groups, Indigenous peoples, and other marginalized groups have experienced a disproportionate burden of environmental and ecological harms. The EJ movement sparked the birth of the EJ field of study. While originally focused on quantitative and distributional understandings of toxic waste in communities of color, the EJ field of study has since expanded to comprise community-based methodologies and new ways to understand justice, including participatory, recognition, and transformational approaches. The EJ field now represents multiple areas such as …


Public Preferences For Renewable Energy Options: A Choice Experiment In Rwanda, Sydney Oluoch, Pankaj Lal, Andres Susaeta, Rodrigue Mugabo, Michel Masozera, Jackline Aridi May 2022

Public Preferences For Renewable Energy Options: A Choice Experiment In Rwanda, Sydney Oluoch, Pankaj Lal, Andres Susaeta, Rodrigue Mugabo, Michel Masozera, Jackline Aridi

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Rwanda has seen impressive economic growth in the past few years resulting from policy driven initiatives. However, one of the key challenges to economic development in Rwanda has been the provision of reliable and cost-effective energy. As a result, the country has planned to expand its renewable energy portfolio to meet its energy demand and mitigate greenhouse gas (GHG) emissions. Meeting these goals requires a robust policy framework that considers the perspective of the public. Moreso, for women who have been disproportionately affected by climate change especially in developing countries. Gender equality is a key for the Rwanda strategy as …


Toxicological Responses To Sublethal Anticoagulant Rodenticide Exposure In Free‑Flying Hawks, Nimish B. Vyas, Barnett A. Rattner, J. Michael Lockhart, Craig S. Hulse, Clifford P. Rice, Frank Kuncir, Kevin Kritz May 2022

Toxicological Responses To Sublethal Anticoagulant Rodenticide Exposure In Free‑Flying Hawks, Nimish B. Vyas, Barnett A. Rattner, J. Michael Lockhart, Craig S. Hulse, Clifford P. Rice, Frank Kuncir, Kevin Kritz

United States Geological Survey: Staff Publications

An important component of assessing the hazards of anticoagulant rodenticides to non-target wildlife is observations in exposed free-ranging individuals. The objective of this study was to determine whether environmentally realistic, sublethal first-generation anticoagulant rodenticide (FGAR) exposures via prey can result in direct or indirect adverse effects to free-flying raptors. We offered black-tailed prairie dogs (Cynomys ludovicianus) that had fed on Rozol® Prairie Dog Bait (Rozol, 0.005% active ingredient chlorophacinone, CPN) to six wild-caught red-tailed hawks (RTHA, Buteo jamaicensis), and also offered black-tailed prairie dogs that were not exposed to Rozol to another two wild-caught RTHAs for 7 …


Draft Final Annual Operations And Maintenance (O&M) Report, Butte Treatment Lagoon (Btl) System – 2021, Pioneer Technical Services, Inc. May 2022

Draft Final Annual Operations And Maintenance (O&M) Report, Butte Treatment Lagoon (Btl) System – 2021, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Specific Properties And Combustion Characteristics Of Natural Coke From Adjacent Areas Of Jiangsu, Shandong, Henan And Anhui Provinces, Qin Yunhu, Wang Shuangmei, Zhu Shifei, Wu Guoqiang, Quan Jutao, Mao Lixin May 2022

Specific Properties And Combustion Characteristics Of Natural Coke From Adjacent Areas Of Jiangsu, Shandong, Henan And Anhui Provinces, Qin Yunhu, Wang Shuangmei, Zhu Shifei, Wu Guoqiang, Quan Jutao, Mao Lixin

Coal Geology & Exploration

It is particularly important to improve resource utilization efficiency against the background of carbon peak and carbon neutrality, but the natural coke has not been paid enough attention for a long time. The natural coke is abundant in China and is often found in the mining of coal mines in neighboring areas of Shandong, Henan and Anhui provinces. Due to the intrusion of magmatic rock, the original coal seam is baked and transformed into natural coke. In this study, samples of natural coke from various areas were collected to study its macroscopic and microscopic characteristics. The industrial analysis, geochemical parameters, …


Nanopore Structure And Surface Roughness In Brittle Tectonically Deformed Coals Explored By Atomic Force Microscopy, Zhang Ningyuan, Yao Suping May 2022

Nanopore Structure And Surface Roughness In Brittle Tectonically Deformed Coals Explored By Atomic Force Microscopy, Zhang Ningyuan, Yao Suping

Coal Geology & Exploration

The pore structure of coal is the key to coalbed methane (CBM) exploration and exploitation, and coal mining safety. Compared to primary coals, tectonically deformed coals (TDCs) have stronger heterogeneity and are of great importance in coal reservoir study. Here, the pore structure and surface roughness of brittle TDCs were obtained with atomic force microscopy (AFM) and NanoScope Analysis and Gwyddion software. The results show that tectonic deformation generally promotes the pore development in brittle TDCs, but the extent of tectonic impact varies greatly among different brittle TDCs. As a result, two stages in brittle TDCs were identified: weak brittle …


Evaluation Method And Application Of Fracturing Effect Based On Dynamic Permeability Change Of Coal Reservoir Hydraulic Fracturing, Shan Tuo, Sun Changyan, Wang Qian, Xie Xiangjun, Fan Yigang May 2022

Evaluation Method And Application Of Fracturing Effect Based On Dynamic Permeability Change Of Coal Reservoir Hydraulic Fracturing, Shan Tuo, Sun Changyan, Wang Qian, Xie Xiangjun, Fan Yigang

Coal Geology & Exploration

The fracturing construction curve is considered to be an important basis for reflecting the fracturing effect, while the dynamic change of reservoir permeability in the fracturing stage can more intuitively reflect the effect of fracture formation. In this paper, a quantitative evaluation method for reservoir dynamic permeability in fracturing stage was established based on the principle of well testing. Then, the method was applied to evaluate the fracturing effect of two coalbed methane (CBM) wells in a block in southern Junggar Basin, and the dynamic permeability curve of reservoir during fracturing stage is obtained. Meanwhile, the G-function method was …


Efficient Treatment Technology Of Incrementally Open Water Gushing Channel Under Dynamic Water Conditions, Pu Zhiguo, Ding Xiang, Li Zhe, Ji Zhuochen, Yan Xin, He Xiaolang, Ma Jianguo May 2022

Efficient Treatment Technology Of Incrementally Open Water Gushing Channel Under Dynamic Water Conditions, Pu Zhiguo, Ding Xiang, Li Zhe, Ji Zhuochen, Yan Xin, He Xiaolang, Ma Jianguo

Coal Geology & Exploration

In Yushen mining area of Shaanxi Province, a blasting expansion fissure on the eastern side of the Xiwan Open-pit Coal Mine communicates the water-bearing body of burnt rock outside the pit, and an incrementally open water gushing channel with a length greater than 65 m is formed. The water volume gushing from burnt rock stabilizes at about 400 m3/h and the flow velocity is as high as 0.36 m/s, resulting in a series of problems in ecology, environmental protection, economy and safety. To block the water gushing channel and solve the problem as soon as possible, a quick …


Optimization Calculation Of The Width Of Waterproof Coal Pillars In Fault Zones Based On Spatial Relationship Between Coal Strata And Fault, Wu Bin, Xie Daolei, Han Jing, Chen Qiang, Zhang Huide May 2022

Optimization Calculation Of The Width Of Waterproof Coal Pillars In Fault Zones Based On Spatial Relationship Between Coal Strata And Fault, Wu Bin, Xie Daolei, Han Jing, Chen Qiang, Zhang Huide

Coal Geology & Exploration

The appropriate setting width of the waterproof coal pillars is an important measure to prevent water inrush hazard during near fault mining. The working face 123up01(south) of Jining No.3 Coal Mine in Shandong Province is adjacent to F8 fault in the west. The fall of F8 fault is large, which may be conducted with the Ordovician limestone aquifer at the bottom. To ensure the safe mining in the working face, it is necessary to calculate the size of waterproof coal pillars of fault F8. In view of the actual occurrence of coal strata, the spatial relationship between fault …


Numerical Simulation Of Azimuth Electromagnetic Wave Response Of Complex Geological Model Of Horizontal Hole In Coal Mines, Zhang Yi, Kang Zhengming, Feng Hong, Han Xue, Chen Gang May 2022

Numerical Simulation Of Azimuth Electromagnetic Wave Response Of Complex Geological Model Of Horizontal Hole In Coal Mines, Zhang Yi, Kang Zhengming, Feng Hong, Han Xue, Chen Gang

Coal Geology & Exploration

The advance and accurate identification of the coal-rock interface is one of the key technologies to realize automatic tunneling and intellectualization of coal mines. Azimuth electromagnetic wave tool has a large detection range and can distinguish the lithologic interface and interface orientation. It has been successfully applied in oilfield logging, but there are few researches on the coal mine measurement environment. In order to study the detection performance of azimuth electromagnetic wave logging in the complex 3D model of coal mines, the finite element numerical simulation method is used to investigate the influence of the drilling fluid in the borehole …


3d Forward Modeling Of Dc Resistivity Method Based On Finite Element With Mixed Grid, Wang Xinyu, Wang Cheng, Mao Yurong, Yan Liangjun, Zhou Lei, Gao Wenlong May 2022

3d Forward Modeling Of Dc Resistivity Method Based On Finite Element With Mixed Grid, Wang Xinyu, Wang Cheng, Mao Yurong, Yan Liangjun, Zhou Lei, Gao Wenlong

Coal Geology & Exploration

The DC resistivity method is widely used in the mineral resources exploration and geological survey industries because of its high efficiency and low cost, such as non-ferrous metals and coal fields. However, in the process of borehole–to–surface and surface–to–borehole resistivity method exploration, the influence of borehole factors (borehole fluid resistivity and borehole diameter) on the apparent resistivity response in different exploration modes is unclear, and whether it will affect the interpretation of apparent resistivity data is an issue worth exploring. Therefore, we proposed a mixed grid finite element method to realize the 3D forward modeling of DC resistivity. Then we …


Preliminary Investigation Of Uranium Resource Evaluation Method Based On Natural Gamma Logging Data:A Case Study Of The Pengyang Uranium Deposit In Ordos Basin, Yu Reng’An, Sun Dapeng, Zhou Xiaoxi, Deng Fan, Si Qinghong, Hu Yongxing May 2022

Preliminary Investigation Of Uranium Resource Evaluation Method Based On Natural Gamma Logging Data:A Case Study Of The Pengyang Uranium Deposit In Ordos Basin, Yu Reng’An, Sun Dapeng, Zhou Xiaoxi, Deng Fan, Si Qinghong, Hu Yongxing

Coal Geology & Exploration

“Coal and uranium exploration” and “oil and uranium exploration” are current research hotspots. Using logging data of coal and oilfield drilling to further evaluate uranium resources remains a difficult problem. Taking the Pengyang uranium deposit in the Ordos Basin as an example, this article explores the method of evaluating uranium resources based on natural gamma logging data. According to the remarkable features of the natural gamma anomaly response in the sandstone-type uranium reservoirs in the study area, the natural gamma logging regression model of the quantitative gamma logging value of the uranium deposit in the Pengyang area was studied by …


Study And Application On Multi Branch Point Sampling Drilling Technology Of Coal Seam Floor Borehole, Chu Zhiwei, Long Weicheng, Jia Bingyi, Liu Fei May 2022

Study And Application On Multi Branch Point Sampling Drilling Technology Of Coal Seam Floor Borehole, Chu Zhiwei, Long Weicheng, Jia Bingyi, Liu Fei

Coal Geology & Exploration

According to the technical requirements of long-distance gas parameter measurement, gas extraction borehole design guidance, and extraction evaluation for broken soft coal seam, the multi branch point sampling drilling method of coal seam floor borehole was proposedand its sampling drilling process was formulated on the basis of analyzing existing problems of sampling and drilling technology. Furthermore, the key drilling technologies such as accurate drilling trajectory control and “mechanical + hydraulic” efficient slag removal were developed. The equipment of drilling and sealed sampling were introduced. The application test was carried out in a coal mine in Suzhou, Anhui Province, in which …


Simplified Internal Variable Gradient Model For Zonal Disintegration Of Rocks In Circular Underground Tunnels, He Ziguang, Zhao Fasuo, Chen Haoxiang, Wu Bo, Zhou Jingjing May 2022

Simplified Internal Variable Gradient Model For Zonal Disintegration Of Rocks In Circular Underground Tunnels, He Ziguang, Zhao Fasuo, Chen Haoxiang, Wu Bo, Zhou Jingjing

Coal Geology & Exploration

As one of the typical nonlinear phenomena of deep level surrounding rock masses, zonal disintegration has captured many attentions of geotechnical engineers in the past years. On the basis of the internal variable theory, the closed-form analytical solutions to stress, strain and displacement fields near circular tunnels are obtained. The gradient-dependent solutions are compared with the results of the classical elasticity theory, and the effects of microstructures on the stresses and deformation fields are investigated as well. It is noted that the stress and deformation fields derived from the gradient model show remarkable quasi-periodicity and fluctuation, which is consistent with …


Powder Discharge Characteristics Of Pneumatic Double Pipe Directional Drilling In Broken Soft Coal Seams And Its Application, Nie Chao, Wang Yi, Yao Yafeng, Hong Jianjun May 2022

Powder Discharge Characteristics Of Pneumatic Double Pipe Directional Drilling In Broken Soft Coal Seams And Its Application, Nie Chao, Wang Yi, Yao Yafeng, Hong Jianjun

Coal Geology & Exploration

To study the influence of casing, casing bit size and casing rotational speed on pulverized coal discharge in double pipe directional drilling technology, three kinds of casing and casing bits in different sizes are designed respectively against the background of pneumatic double pipe directional drilling in the broken soft coal seam, the changes of the discharge rate and outlet velocity of pulverized coal under different combinations are analyzed, and the influence law of different casing rotational speeds on the suspension rate and conveying trajectory of pulverized coal are obtained. The numerical simulation results show that the ø120/96 mm casing with …


Failure Analysis Of Deep Coal Seam Floor Considering Strain Softening Of Surrounding Rock And Formation Contact In Goaf, Yin Shangxian, Meng Haopeng, Qian Shuangbin May 2022

Failure Analysis Of Deep Coal Seam Floor Considering Strain Softening Of Surrounding Rock And Formation Contact In Goaf, Yin Shangxian, Meng Haopeng, Qian Shuangbin

Coal Geology & Exploration

In order to study the failure mode of the floor in deep coal seam mining, we proposed a FLAC3D finite difference numerical method considering the strain softening of surrounding rock and the contact of goafs .Through the qualitative analysis of Rankine’s earth pressure theory, the failure of the deep coal seam floor is studied based on the measured water conducting fracture zone of the floor in working face 2023 of Linxi Mine. The results show that the mechanical state of surrounding rock after plastic failure can be described more accurately by using the strain-softening constitutive relationship instead of the …


Temperature Field Analysis Of New Pipe Curtain Freezing Method In River Embankment Anti Seepage Reinforcement, Zhou Yuxuan, Hu Jun, Xiong Hui, Ren Junhao, Zhan Jianjian, Wang Zhixin May 2022

Temperature Field Analysis Of New Pipe Curtain Freezing Method In River Embankment Anti Seepage Reinforcement, Zhou Yuxuan, Hu Jun, Xiong Hui, Ren Junhao, Zhan Jianjian, Wang Zhixin

Coal Geology & Exploration

In order to explore whether the new pipe curtain freezing method can effectively strengthen the river embankment, this paper uses the finite element software to study the application of the new pipe curtain freezing method in anti-seepage and embankment reinforcement based on the temperature field, and sets up four analysis paths to deeply analyze the basic situation of the frozen soil curtain and the freezing effect characteristics of each path. The results show that the frozen soil curtain spreads around after it is formed at the freezing pipe. From the 8th day, the development of the frozen soil curtain on …