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Study On The Effect Of Coal Microscopic Pore Structure To Its Spontaneous Combustion Tendency, Xianwei Dong, Gaojing Li, Xuanmeng Dong, Fusheng Wang

Journal of Sustainable Mining

Coal is a porous medium. Due to the large number of pores in coal and the pore size on its surface, usually ranging from millimeter to nanometer, it is difficult to measure and analyze the microscopic pore structure of coal. In order to investigate the effect of the microscopic pore structure of coal on its spontaneous combustion tendency, coal samples from different coal mines of the Kailuan Group were selected as the research objects, and the data of the microscopic pore distribution of three different coal samples were measured by using mercury injection apparatus. The regression analysis of microscopic pore …

Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 50 – Zelia (Dated June 22, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 93 – Soudan Dump (Dated June 23, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Comments On The Draft Butte Priority Soils Operable Unit (Bpsou) 2021 Draft Site- Wide Surface Water Monitoring Data Summary Report (Dated April 4, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Potential Economic And Environmental Benefits Of Faecal Sludge Derived Compost And Char Briquettes: The Case Of Dar Es Salaam, Tanzania, Isabela T Mkude, Richard Kimwaga, Sara Gabrielsson

Tanzania Journal of Science

The concept of resource recovery, particularly from waste has recently gained much attention and popularity. The aim of this study was to quantify the potential economic and environmental benefits of recovering nutrients and energy from faecal sludge (FS). The empirical data were collected from three unplanned settlements of Dar es Salaam City at Keko, Kipawa and Manzese. Two scenarios were developed to recover nutrients and energy. The estimations of potential amounts of compost and char briquettes were performed by using the resource value mapping (REVAMP) tool. Results from REVAMP indicated daily economic benefits across the study areas ranging between 680 …

Impact Of Radio Operating Environments On Broadband Connectivity, Libe V Massawe, Peter J Chitamu

Tanzania Journal of Science

Broadband connectivity and services commonly referred to as the Internet is the key enabling facility for the modern digital economy and the driver for the Fourth Industrial Revolution (4IR or Industry 4.0). In Tanzania, there are over 49% Internet subscriptions for mobile broadband services using 3G UMTS and 4G standards infrastructure, which are predominantly available in urban areas. The non-urban areas remain mostly 2G coverage areas and lack mobile broadband connectivity and services. Transforming existing 2G mobile networks to broadband infrastructure can be achieved by swapping 2G sites with 3G or 4G sites or incrementally replacing 2G sites with 3G …

Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 32 – Corra-2 Dumps (Dated June 20, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

An Integrated Approach For Dynamic Process Modeling And Optimization Of Wastewater Treatment Facilities, Komal Rathore

USF Tampa Graduate Theses and Dissertations

The subareas of process systems engineering including process modeling, simulation, and optimization are becoming progressively substantial for understanding processes, making decisions, improving efficiency, and complying with stricter environmental and safety legislation. Additionally, the availability of user-friendly flowsheet simulators and computational resources with the current trend of data collection and analysis has allowed for a more accurate representation of complex processes such as wastewater treatment systems. Despite all the progress in the areas of process modeling and simulation, the first-principle mechanistic models for wastewater treatment processes are at best employed during the design stage, and therefore, not used optimally for day-to-day …

Assessing The Human-Health Risk Of Exposure To Pathogens From Beach Sands, Javier Federico Gallard-Góngora

USF Tampa Graduate Theses and Dissertations

Fecal contamination at recreational beaches impacts the health of beachgoers, through the introduction of disease-causing microorganisms, and the well-being of communities dependent on income from recreational beach activities. Beach ecosystems are also impacted by sewage through the introduction of nutrients that can cause abnormal increases in autochthonous microorganisms which can impact the population of larger organisms in the ecosystem. Fecal contamination is introduced into sand via untreated sewage, direct deposition of human feces into sand, runoff, and deposition of animal feces into sand. The introduction of fecal contamination into sand exposes individuals to pathogens (disease causing microorganisms) which can result …

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.

Final Revised Butte Reduction Works (Brw) Phase Iii Qapp, Nikia Greene, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Multiple Solar Receivers Arrangement For High-Temperature Power Generation And Applications, Diego Jesus Guillen Perez

USF Tampa Graduate Theses and Dissertations

This dissertation presents an investigation of the specification and operation of multiple central solar receivers (CSR) sharing a heliostat field and an analysis of the receiver's thermal performance. A heliostat field was modeled in which different parts of the field aimed at different external or cavity receivers located on the same tower. Optical and thermal performance are analyzed, including the receivers' heat flux, solar thermal efficiency, and annual energy output. Some of the contributions of this research are:

1. Propose a novel configuration for a CSP power generation system using two receivers in a single central tower suitable …

Approval On The Draft Butte Priority Soils Operable Unit (Bpsou) Blacktail Creek Piezometer Installation And Monitoring Well Repair Plan (Dated June 10, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Biomass Residues Improve Soil Chemical And Biological Properties Reestablishing Native Species In An Exposed Subsoil In Brazilian Cerrado, Thaís Soto Boni, Engil Isadora Pujol Pereira, Adriana Avelino Santos, Ana Maria Rodrigues Cassiolato, Kátia Luciene Maltoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Revegetation of exposed sub-soil, while a desirable strategy in the recovery processes, often fails due to extreme soil chemical properties, such as low organic matter and pH levels inhospitable to biological activities such as nutrients cycling and plant establishment. This is the case for approximately 800 ha of the Cerrado biome in Brazil, where erecting the embankment of a hydroelectric dam in the 1960’s stripped vegetation, soil, and subsoil layers thereby distorting the soil properties. This work evaluates the effectiveness of restoration management (RM) treatments, to restore the soil quality, including biological activity and chemical attributes. In a factorial scheme, …

Final 2022 Residential Metals Abatement Program (Rmap) Park Soil Sampling Field Sampling Plan (Fsp) Submittal #6 [Covering Stodden Park, Baptist Student Union, Minor Park, Blacktail Lane, Earth Lane, Fleecer Drive, Boulevard (Josette), Boulevard (Lasalle), And Sesame- Sage], Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoon System – First Quarter 2022, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

The Ddt-Induced Decline Influenced Genetic Diversity In Naturally Recovered Peregrine Falcons (Falco Peregrinus) Nesting Within The Alaska Arctic And Eastern Interior, Sarah A. Sonsthagen,, Ted Swem, Skip Ambrose, Melanie J. Flamme, Clayton M. White, George K. Sage, Sandra L. Talbot

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We assessed the influence of the severe mid-20th century population decline on genetic diversity in nonaugmented Peregrine Falcon Falco peregrinus populations nesting within the Alaska Arctic and eastern Interior. Microsatellite and mitochondrial DNA (mtDNA) data were analysed for Peregrine Falcons sampled from three periods: pre-decline, decline and post-decline. The influence of the decline on genetic diversity differed between the two locales. The Alaska Arctic was characterized by shifts in mtDNA haplotype frequencies, increased inbreeding coefficient, reduction in effective population size and increase in private haplotypes, and a signature of post-decline population growth was detected; by contrast, the eastern Interior showed …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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, …

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 …

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, …

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 …