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Articles 40861 - 40890 of 302505

Full-Text Articles in Physical Sciences and Mathematics

Long-Term Socio-Ecological Research In The Biosphere Reserve In Mapimi, Mexico: A Multidimensional Participatory Observatory Of Rangeland/Pastoral Systems, V. M. Reyes Gómez, Elisabeth Huber-Sannwald, N. Martínez Tagüeña, I. Espejel Carvajal, S. Lucatello, M. A. Bowker, C. L. Lauterio Martínez Oct 2021

Long-Term Socio-Ecological Research In The Biosphere Reserve In Mapimi, Mexico: A Multidimensional Participatory Observatory Of Rangeland/Pastoral Systems, V. M. Reyes Gómez, Elisabeth Huber-Sannwald, N. Martínez Tagüeña, I. Espejel Carvajal, S. Lucatello, M. A. Bowker, C. L. Lauterio Martínez

IGC Proceedings (1993-2023)

Since the creation of the UNESCO Biosphere Reserve Mapimi (BRM) in Mexico 45 years ago, pastoralism has undergone a series of transformations. Upon the arrival of the Spaniards, horse breeding flourished until 1900; thereafter extensive cattle production lasted for six decades. Only recently, farmers have adopted alternative management types for organic meat production. National and international efforts to achieve the Sustainable Development Goals (SDGs) require basic, applied, and participatory research efforts. In the socio-ecological pastoral system BRM, first halophytic ecosystems were examined for their ecohydrological role in rangeland productivity. In 1996, a long-term ecological research site was installed to monitor …

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Re-Envisioning Global Rangeland Stewardship: An Ecosystem Services Assessment Framework, David D. Briske Oct 2021

Re-Envisioning Global Rangeland Stewardship: An Ecosystem Services Assessment Framework, David D. Briske

IGC Proceedings (1993-2023)

Rangeland stewardship may be enhanced by transforming the global narrative from one of ‘resource scarcity and unpredictability’ to one of ‘global rangeland value’. This may be accomplished by devising a stewardship strategy founded on a more complete accounting of rangeland ecosystem services to inform land use planning and decision making. An ecosystem services framework may provide the necessary feedbacks to identify and assess potential tradeoffs among ecosystem services prior to implementing land use actions and policy. The ultimate goal of this alternative stewardship strategy would be to provide optimal combinations of ecosystem services to meet the needs of global citizens, …

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Mongolian Herders’ Evaluation Of Rangeland Ecosystems Services, Values, And Changes Over The Past Decade, T. Ulambayar, B. Yunden, N. Davaasuren, S. Balt, D. Davaajav, B. Zambuu Oct 2021

Mongolian Herders’ Evaluation Of Rangeland Ecosystems Services, Values, And Changes Over The Past Decade, T. Ulambayar, B. Yunden, N. Davaasuren, S. Balt, D. Davaajav, B. Zambuu

IGC Proceedings (1993-2023)

Mongolia's rangeland is one of the largest remaining contiguous ecosystems encompassing 2.6% of the global grasslands, and almost three-fourths of the country's territory provides essential ecosystem services (ESS) for over 3 million Mongolians and 71 million livestock. The well-being of 171,605 pastoral households directly depends on the rangelands receiving provisional services in the forms of nutrition, material use and energy, regulatory services, and cultural services. This study explored herders' perceptions of these ESS, their evaluation for ESS values, and observations of ESS change for the last decade. The study found that Mongolian herders have more benefits from provisional ESS (on …

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Conceptualizing Pastoral Development Based On Carbon Sequestration: The Case Of Yabelo District In The Southern Ethiopian Rangelands, D. L. Coppock Oct 2021

Conceptualizing Pastoral Development Based On Carbon Sequestration: The Case Of Yabelo District In The Southern Ethiopian Rangelands, D. L. Coppock

IGC Proceedings (1993-2023)

Major challenges for rangeland stewardship in the developing world include how to mitigate the spread of pastoral poverty and environmental degradation. Arresting such trends requires a scale of investment, policy incentives, and institutional commitments not previously observed in pastoral development. Indeed, such a rangeland revolution requires several global events to set the stage, namely: (1) Creation of markets for diverse ecosystem services; (2) recognition that improved rangeland stewardship is vital to mitigate climate change; and (3) distribution of green climate funds in support of local projects. New approaches for pastoral development projects are also needed. Previous projects have largely focused …

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Wildlife Conservation And The Role Of The Indigenous Communities Living Around Conservation Areas, N. Parmisa, K. A. Galvin Oct 2021

Wildlife Conservation And The Role Of The Indigenous Communities Living Around Conservation Areas, N. Parmisa, K. A. Galvin

IGC Proceedings (1993-2023)

The Indigenous Kenyan Maasai community has coexisted with the wildlife surrounding it for decades from Nairobi National Park, Maasai Mara and Amboseli. These parks border Maasai lands. Although the northern, eastern, and western perimeters of the Nairobi National Park are fenced, the southern part is not. It is at this point that the Maasai community’s land meets the park. This area also acts as a wildlife dispersal area where wildlife can freely migrate to other parks, including Maasai Mara and Amboseli. The park is only 117sq kms and its vitality depends on the plains to the south where the Maasai …

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Whose Knowledge Counts?: Irrigation Development In Turkana, Kenya (1963-2019), G. L. Akall Oct 2021

Whose Knowledge Counts?: Irrigation Development In Turkana, Kenya (1963-2019), G. L. Akall

IGC Proceedings (1993-2023)

Irrigation has long been promoted in Africa’s drylands as a means to improve food security and livelihoods. Turkana County, one of the driest regions of Kenya, has a long history of irrigation interventions, extending from the colonial era to the present. The recent discovery of two huge water aquifers in the arid Turkana region, Kenya’s Vision 2030 and devolution has fed into enthusiasm for irrigation as an excellent solution to the multiple problems in the region against other activities like pastoralism. This is in spite of a history of failed irrigation developments in Turkana (Hogg 1987). This paper explores the …

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Co-Produced Research Supports Pastoralists To Pursue Transformative Social And Ecological Change In Rangelands, R. S. Reid, K-A. S. Kassam, T. Pickering, A. Yasin, Chantsallkham Jamsranjav, Khishigbayar Jamiyansharav, Tungalag Ulambayar, Corrine N. Knapp Oct 2021

Co-Produced Research Supports Pastoralists To Pursue Transformative Social And Ecological Change In Rangelands, R. S. Reid, K-A. S. Kassam, T. Pickering, A. Yasin, Chantsallkham Jamsranjav, Khishigbayar Jamiyansharav, Tungalag Ulambayar, Corrine N. Knapp

IGC Proceedings (1993-2023)

Over the last two decades, pastoralists and researchers have formed powerful alliances to transform how we think about and do research-with-action in rangelands. These alliances promote faster learning about problems and their potential solutions by bringing together diverse partners and their different ways of understanding important issues. They also ensure research is fully relevant to real problems, so it supports pastoralists to act on both old and new issues that they face. While these approaches can be contentious when perspectives and experiences do not align, team members are finding them transformative, if they commit to working together over the long …

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Land Use Planning For Resilient Pastoral Rangelands: Greater Serengeti Mara Ecosystem, Y. M. Said, B. J. Graae, M. Nielsen, H. P. Hartstean Oct 2021

Land Use Planning For Resilient Pastoral Rangelands: Greater Serengeti Mara Ecosystem, Y. M. Said, B. J. Graae, M. Nielsen, H. P. Hartstean

IGC Proceedings (1993-2023)

Greater Serengeti Mara Ecosystem (GSME) encompasses large protected areas of savanna with iconic wildlife surrounded by pastoralists and farms. GSME is facing severe pressure from human-induced changes due to rapid increase in population and climate variability. We undertook surveys with local communities to understand the potential impacts of these changes on wildlife and livelihoods of communities. We visited eight villages in Kenya and Tanzania and discussed with local communities and leaders, park management on drivers of change, and wishes for future development. To facilitate the conversation, we developed posters with four scenarios as a basis for discussions and a board …

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Producing Useful Knowledge For Sustainable Development, K. A. Galvin Oct 2021

Producing Useful Knowledge For Sustainable Development, K. A. Galvin

IGC Proceedings (1993-2023)

Africa makes a relatively minor contribution to global greenhouse gas emissions compared with developed nations, yet the African continent will be increasingly vulnerable to climate change processes in the coming decades. Critical challenges include meeting basic needs for food, water, shelter, and other necessities without undermining biodiversity and ecosystem services. Coordination efforts to address multiple global change related stressors has generally occurred at the national level and taken an external approach, with national governments favoring collaboration with foreign-based NGOs and other international institutions. However, the involvement of actors at the local level correlates with decisions that are better adapted to …

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Evolutionary Design Of Search And Triage Interfaces For Large Document Sets, Jonathan A. Demelo Oct 2021

Evolutionary Design Of Search And Triage Interfaces For Large Document Sets, Jonathan A. Demelo

Electronic Thesis and Dissertation Repository

This dissertation is concerned with the design of visual interfaces for searching and triaging large document sets. Data proliferation has generated new and challenging information-based tasks across various domains. Yet, as the document sets of these tasks grow, it has become increasingly difficult for users to remain active participants in the information-seeking process, such as when searching and triaging large document sets. During information search, users seek to understand their document set, align domain knowledge, formulate effective queries, and use those queries to develop document set mappings which help generate encounters with valued documents. During information triage, users encounter the …

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A Clark-Ocone Type Formula Via Itô Calculus And Its Application To Finance, Takuji Arai, Ryoichi Suzuki Oct 2021

A Clark-Ocone Type Formula Via Itô Calculus And Its Application To Finance, Takuji Arai, Ryoichi Suzuki

Journal of Stochastic Analysis

No abstract provided.

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Relationships Among Toilet Sharing, Water Source Locations, And Handwashing Places Without Observed Soap: A Cross-Sectional Study Of The Richest Households In Bangladesh, Mazbahul G. Ahamad, Mark Burbach, Fahian Tanin Oct 2021

Relationships Among Toilet Sharing, Water Source Locations, And Handwashing Places Without Observed Soap: A Cross-Sectional Study Of The Richest Households In Bangladesh, Mazbahul G. Ahamad, Mark Burbach, Fahian Tanin

School of Natural Resources: Faculty Publications

Background: A high percentage of the richest households in Bangladesh lack soap at their handwashing places, a problem that is typically considered to be one of the poor. Objective: We investigated toilet sharing practices, locations of water sources, and relevant sociodemographic factors associated with the observed handwashing places that lack soap in the richest (ninth wealth decile) households in Bangladesh. Methods: We used data from the 2017-18 Bangladesh Demographic and Health (BDHS) Survey. Logistic regression technique was used to investigate how toilet sharing practices, water source locations, and different sociodemographic factors were associated with observed handwashing places without soap. Results: …

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Comments On The Holographic Description Of Narain Theories, Anatoly Dymarsky, Alfred D. Shapere Oct 2021

Comments On The Holographic Description Of Narain Theories, Anatoly Dymarsky, Alfred D. Shapere

Physics and Astronomy Faculty Publications

We discuss the holographic description of Narain U(1)c × U(1)c conformal field theories, and their potential similarity to conventional weakly coupled gravitational theories in the bulk, in the sense that the effective IR bulk description includes “U(1) gravity” amended with additional light degrees of freedom. Starting from this picture, we formulate the hypothesis that in the large central charge limit the density of states of any Narain theory is bounded by below by the density of states of U(1) gravity. This immediately implies that the maximal value of the spectral gap for primary fields is ∆1 = …

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Mgrre_Pureoilscouttickets_Robertson_1_21127021230000, Mgrre Oct 2021

Mgrre_Pureoilscouttickets_Robertson_1_21127021230000, Mgrre

Legacy Scout Tickets from Pure Oil Company

No abstract provided.

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Ferromagnetic Resonances In Single-Crystal Yttrium Iron Garnet Nanofilms Fabricated By Metal-Organic Decomposition, Szu Fan Wang, Kayetan Chorazewicz, Suvechhya Lamichhane, Ronald A. Parrott, Stefano Cabrini, Peter Fischer, Noah Kent, John H. Turner, Takayuki Ishibashi, Zachary Parker Frohock, Jacob J. Wisser, Peng Li, Ruthi Zielinski, Bryce Herrington, Yuri Suzuki, Mingzhong Wu, Keiko Munechika, Carlos Pina-Hernandez, Robert Streubel, Allen A. Sweet Oct 2021

Ferromagnetic Resonances In Single-Crystal Yttrium Iron Garnet Nanofilms Fabricated By Metal-Organic Decomposition, Szu Fan Wang, Kayetan Chorazewicz, Suvechhya Lamichhane, Ronald A. Parrott, Stefano Cabrini, Peter Fischer, Noah Kent, John H. Turner, Takayuki Ishibashi, Zachary Parker Frohock, Jacob J. Wisser, Peng Li, Ruthi Zielinski, Bryce Herrington, Yuri Suzuki, Mingzhong Wu, Keiko Munechika, Carlos Pina-Hernandez, Robert Streubel, Allen A. Sweet

Robert Streubel Papers

Tunable microwave and millimeter wave oscillators and bandpass filters with ultra-low phase noise play a critical role in electronic devices, including wireless communication, microelectronics, and quantum computing. Magnetic materials, such as yttrium iron garnet (YIG), possess ultra-low phase noise and a ferromagnetic resonance tunable up to tens of gigahertz. Here, we report structural and magnetic properties of single-crystal 60 and 130 nm-thick YIG films prepared by metal-organic decomposition epitaxy. These films, consisting of multiple homoepitaxially grown monolayers, are atomically flat and possess magnetic properties similar to those grown with liquid-phase epitaxy, pulsed laser deposition, and sputtering. Our approach does not …

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Structural And Morphological Properties Of Wool Keratin And Cellulose Biocomposites Fabricated Using Ionic Liquids, Karleena Rybacki, Stacy A. Love, Bailey Blessing, Abneris Morales, Emily Mcdermott, Kaylyn Cai, Xiao Hu, David Salas-De La Cruz Oct 2021

Structural And Morphological Properties Of Wool Keratin And Cellulose Biocomposites Fabricated Using Ionic Liquids, Karleena Rybacki, Stacy A. Love, Bailey Blessing, Abneris Morales, Emily Mcdermott, Kaylyn Cai, Xiao Hu, David Salas-De La Cruz

College of Science & Mathematics Departmental Research

In this study, the structural, thermal, and morphological properties of biocomposite films composed of wool keratin mixed with cellulose and regenerated with ionic liquids and various coagulation agents were characterized and explored. These blended films exhibit different physical and thermal properties based on the polymer ratio and coagulation agent type in the fabrication process. Thus, understanding their structure and molecular interaction will enable an understanding of how the crystallinity of cellulose can be modified in order to understand the formation of protein secondary structures. The thermal, morphological, and physiochemical properties of the biocomposites were investigated by Fourier transform infrared (FTIR) …

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Confirmation Of Carbon Emissions In Coal Mining Areas And Research On Low-Carbon Green Development Path, Wang Meng, Ma Ruying, Dai Xuguang, Shan Yadi Oct 2021

Confirmation Of Carbon Emissions In Coal Mining Areas And Research On Low-Carbon Green Development Path, Wang Meng, Ma Ruying, Dai Xuguang, Shan Yadi

Coal Geology & Exploration

Analysis was carried out on the issues such as unclear boundaries of carbon emission sources in coal mining areas, lack of accounting models, and development directions in the context of carbon neutrality. Based on the previous researches and through literature review, data collection and other methods, the boundaries of carbon emission sources in coal mining areas have been clarified and accounting model has been established, clarifying the low-carbon and green development direction of coal mining areas. The sources of carbon emissions(CH4 and CO2) in coal mining areas are divided into two major categories: natural emission and anthropogenic …

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Mine Water Inflow Modes And Scientific Design Of Drainage Boreholes In Roof Confined Aquifer Of Coal Seam, Hu Weiyue, Ji Yadong, Huang Huan Oct 2021

Mine Water Inflow Modes And Scientific Design Of Drainage Boreholes In Roof Confined Aquifer Of Coal Seam, Hu Weiyue, Ji Yadong, Huang Huan

Coal Geology & Exploration

Aiming at the uncertainty of mine water inflow mode, this paper analyzes the spatiotemporal variation characteristics of mine water inflow at first, and get a conclusion that the mine water is composed of static storage and dynamic recharge. And the static storage is mainly affected by weighting interval, the aquifer thickness of caving and fracture zone height and specific yield; the dynamic recharge is mainly affected by caving and fracture zone height and specific yield, hydraulic gradient in permeable flow field and discharge section area. According to the spatial relationships between water conducted fissure and roof aquifer of coal seam, …

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Research On Three-Component Response Of Ground-Airborne Tem Considering Emission Current Waveform, Hou Yanwei, Guo Jianlei, Si Yinnyu, Jiang Tao Oct 2021

Research On Three-Component Response Of Ground-Airborne Tem Considering Emission Current Waveform, Hou Yanwei, Guo Jianlei, Si Yinnyu, Jiang Tao

Coal Geology & Exploration

The ground-airborne TEM has received more and more attention in coal goaf exploration and other fields. In order to provide a theoretical basis for the processing and interpretation of ground-airborne transient electromagnetic data, it is necessary to study the influence of the transmitted current waveform parameter on the three-component response characteristics of ground-airborne TEM. Taking trapezoidal waves as an example, this article firstly studies the frequency distribution of different emission current waveform, and then investigates the effects of the rising edge time, pulse width and turn-off time of the transmitted waveform on the three-component magnetic field response of ground-air transient …

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Coupling Simulation Of Groundwater Dynamics And Solute Transfer In The Process Of Deep Reinjection Of Mine Water, Zhao Chunhu, Yang Jian, Wang Shidong, Zhou Jianjun, Xu Feng, Liu Ji Oct 2021

Coupling Simulation Of Groundwater Dynamics And Solute Transfer In The Process Of Deep Reinjection Of Mine Water, Zhao Chunhu, Yang Jian, Wang Shidong, Zhou Jianjun, Xu Feng, Liu Ji

Coal Geology & Exploration

The deep well reinjection of mine water is a main form of "transfer storage" treatment of mine water. According to the geological and mine water characteristics of the coal mine area in Ordos Basin, the paper puts forward the basis for selecting the target layer of mine water reinjection from the perspective of good matching between groundwater and mine water in the target layer of reinjection, the water isolation of upper and lower strata, permeability and sealing of the reinjection layer. Based on Darcy's law of groundwater and Dupuit's theory, a mathematical model of steady flow of water injection well …

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Heavy Metal Pollution Characteristics And Source Analysis Of Water Drainage From A Mine In Inner Mongolia, Wang Tiantian, Jin Dewu, Yang Jian Oct 2021

Heavy Metal Pollution Characteristics And Source Analysis Of Water Drainage From A Mine In Inner Mongolia, Wang Tiantian, Jin Dewu, Yang Jian

Coal Geology & Exploration

Heavy metal pollution evaluation and its source analysis are essential to mine water reuse and protection of ecological environment in mining areas. The objective of this paper is to study heavy metal pollution characteristics and source of heavy metal in mine water. A coal mine from Inner Mongolia Province was chosen as the study area and 49 water samples including surface water, quaternary groundwater, confined groundwater and mine water were collected. Primarily, we detected the concentrations of Zn, Pb, Fe, Mn, As, Cu, Cd, Cr, Hg and Se of water samples to explore heavy metal pollution characteristics and excessive situation. …

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Hydrochemical Characteristics And Genetic Mechanism Of High Tds Groundwater In Xinjulong Coal Mine, Zhang Yuzhuo, Xu Zhimin, Zhang Li, Lyu Weikui, Yuan Huiqing, Zhou Lijie, Gao Yating, Zhu Lulu Oct 2021

Hydrochemical Characteristics And Genetic Mechanism Of High Tds Groundwater In Xinjulong Coal Mine, Zhang Yuzhuo, Xu Zhimin, Zhang Li, Lyu Weikui, Yuan Huiqing, Zhou Lijie, Gao Yating, Zhu Lulu

Coal Geology & Exploration

Based on historical water quality data and sampling test results, using Piper three-line diagram, correlation analysis, hydrogen and oxygen isotope, Gibbs diagram, ion ratio and saturation index, etc., the hydrochemical characteristics and genetic mechanism of the groundwater with high TDS in Xinjulong Coal Mine area were explored. The results show that with the proceeding of mine construction and coal mining, the water chemistry environment in the study area has changed. The water chemistry type is no longer a single SO4-Na type, with SO4·HCO3-Na and SO4-Ca·Mg type appearing in the deep limestone water. …

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Optimization Of Regional Advanced Coal Floor Water Hazard Prevention And Control Technology And Its Application, Zheng Shitian, Ma Hewen, Ji Yadong Oct 2021

Optimization Of Regional Advanced Coal Floor Water Hazard Prevention And Control Technology And Its Application, Zheng Shitian, Ma Hewen, Ji Yadong

Coal Geology & Exploration

In order to optimize the grouting process, improve the effect of the technology, and promote its application, this paper presents an investigation on the application of the regional advanced coal floor water hazard prevention and control technology in Huaibei mining area. The investigation shows that the pressure control in low pressure diffusion and medium pressure strengthening stages plays a major role in controlling the total grouting volume, which directly affects the limestone aquifer reformation. The prediction formula for grouting volume for strata with different karst fractures can provide guidance to the grouting engineering design. In addition, the horizontal layout method …

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Statistical Regularity Of Physical And Mechanical Indexes Of Secondary Red Clay In Chenggong District, Kunming, Gao Haiyan, Zhang Jiaming Oct 2021

Statistical Regularity Of Physical And Mechanical Indexes Of Secondary Red Clay In Chenggong District, Kunming, Gao Haiyan, Zhang Jiaming

Coal Geology & Exploration

In order to analyze the statistical regularity of physical and mechanical indexes of secondary red clay in Chenggong District, Kunming, the index data of 275 groups of secondary red clay samples from 69 geotechnical investigation boreholes in Wujiaying area of Chenggong are taken as the research object. Based on the statistical analysis principle, the variation range, average value, standard deviation, coefficient of variation of 13 indexes and the correlation between indexes and depth are analyzed by SPSS statistical analysis software, and the physical and mechanical properties of secondary red clay are summarized. Then, the linear empirical formula between indexes is …

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Performance Deterioration Law Of Retarded Cement Slurry And Its Mixed Slurry In Freezing Borehole Mud Replacement, Li Qiang, Wang Yansen, Wang Chunlin, Xu Shengji, Fan Zhiqiang Oct 2021

Performance Deterioration Law Of Retarded Cement Slurry And Its Mixed Slurry In Freezing Borehole Mud Replacement, Li Qiang, Wang Yansen, Wang Chunlin, Xu Shengji, Fan Zhiqiang

Coal Geology & Exploration

The mud replacement of freezing hole has become a necessary part of freezing shaft sinking in rock strata, but in the lowering process, the freezing pipe is prone to excessive slurry viscosity resistance, and even be locked, leading to borehole failure. In order to deeply understand the performance deterioration law of cement slurry and its mixture in deep hole environment, the laboratory tests of retarded cement slurry and mixed slurry are carried out respectively, taking the apparent viscosity as the measurement index and considering the factors such as curing time, temperature, water loss state and volume ratio of mixed slurry. …

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Research On The Integrated Electric Exploration System For Coal Mines And Its Application, Liu Baobao, Guo Chun, Yang Haitao Oct 2021

Research On The Integrated Electric Exploration System For Coal Mines And Its Application, Liu Baobao, Guo Chun, Yang Haitao

Coal Geology & Exploration

In order to overcome the shortcomings of the existing electrical prospecting technology in coal mines, such as multiple construction of electrical sounding, electrical profile and electrical penetration and a scarcity of data collected, an integrated electrical prospecting system is successfully designed, absorbing the idea of parallel electrical data acquisition, and applying the "rectangular wave" electrode layout mode combined with the "multi device data extraction" technology. The experimental results show that the system can complete the original data acquisition of electrical sounding, electrical profile, electrical perspective and other electrical construction methods with one-time wiring and one-round power supply, and extract the …

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Application Of Air Foam Composite Directional Drilling Technology In Broken Soft Coal Seams, Liu Jianlin, Fang Jun, Chu Zhiwei, Yang Weifeng Oct 2021

Application Of Air Foam Composite Directional Drilling Technology In Broken Soft Coal Seams, Liu Jianlin, Fang Jun, Chu Zhiwei, Yang Weifeng

Coal Geology & Exploration

In order to meet the requirements of air screw motor cooling and lubrication, coal dust removal treatment at the orifice and water outlet disposal in the air directional drilling, an air foam composite directional drilling technology for broken soft coal seams has been developed based on the analysis of drilling slag migration characteristics of air directional drilling. The key technologies such as stable and efficient foaming, "mechanical + foam" composite slag discharge and "air + foam" composite drilling were integrated. The technology was also equipped with directional drillrig, foam generation perfusion system, air screw motor, special-shaped drill pipe and measurement …

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Medium Characteristics And Hydrodynamic Evolution Law Of High Salinity Mine Water Recharge In Deep Well, Liu Qi, Wang Weijun, Luo Bin, Wang Houzhu, Zhang Zhijun Oct 2021

Medium Characteristics And Hydrodynamic Evolution Law Of High Salinity Mine Water Recharge In Deep Well, Liu Qi, Wang Weijun, Luo Bin, Wang Houzhu, Zhang Zhijun

Coal Geology & Exploration

The treatment and discharge of high salt mine water is one of the important factors affecting efficient coal mining in recent years. It is a worth exploring method to reduce the discharge of mine water by selecting the appropriate aquifer under the floor of the coal seam and transferring the high salt mine water to other places. Taking the X mine in the Ordos Basin as an example, the Baotashan sandstone and the deep Liujiagou Formation sandstone formation below the coal seam have transfer storage space. By mercury intrusion experiment and rock mechanics analysis, the two groups of formations were …

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Mine Water Drainage Pollution In China's Coal Mining Areas And The Construction Of Prevention And Control Technical System, Sun Yajun, Xu Zhimin, Li Xin, Zhang Li, Chen Ge, Zhao Xianming, Gao Yating, Liu Qi, Zhang Shangguo, Wang Weijun, Zhu Lulu, Wang Sheng Oct 2021

Mine Water Drainage Pollution In China's Coal Mining Areas And The Construction Of Prevention And Control Technical System, Sun Yajun, Xu Zhimin, Li Xin, Zhang Li, Chen Ge, Zhao Xianming, Gao Yating, Liu Qi, Zhang Shangguo, Wang Weijun, Zhu Lulu, Wang Sheng

Coal Geology & Exploration

Mining activities are bound to produce enormous mine water drainage. Mine water in China shows relatively poor water quality and high cost of water treatment and other problems. Firstly, the main characteristics of mine water quality in China's typical mine areas are clarified in this paper: conventional ions are the main chemical components causing poor mine water quality; mine water has a small proportion of toxic and harmful substances, which is generally better than the quality standard of class Ⅲ groundwater. Secondly, some scientific issues on the formation and evolution of mine water quality are discussed in detail, including the …

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Distribution Characteristics And Paleo-Climatic Significance Of Continental Climate-Sensitive Sediments In The Late Cretaceous In China, Bin Xu, Fang Xiang, Shuxia Li Oct 2021

Distribution Characteristics And Paleo-Climatic Significance Of Continental Climate-Sensitive Sediments In The Late Cretaceous In China, Bin Xu, Fang Xiang, Shuxia Li

Coal Geology & Exploration

The Cretaceous is a typical period for studying the greenhouse climate and the earth system interactions, and the world's most extensive terrestrial strata are mainly in East Asia, especially in China. Continental sediments can effectively reflect the paleo-climate change, but the previous studies of the Late Cretaceous paleo-climate, based on the combined characteristics of continental climate-sensitive sediments, were barely found in China. To obtain the Late Cretaceous paleo-climate characteristics of China, the distribution characteristics of different continental climate-sensitive sediment types in the early, middle and Late Cretaceous in China were studied in detail. According to the distribution and combination characteristics …

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