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Full-Text Articles in Physical Sciences and Mathematics

Analysis And Application Of Key Influencing Factors Of Cbm Well Fracturing Effects In Shizhuang Area, Qinshui Basin, Xue Haifei, Zhu Guanghui, Wang Wei, Lu Xiaoxia, Wang Minghao, Wang Yanbin Aug 2019

Analysis And Application Of Key Influencing Factors Of Cbm Well Fracturing Effects In Shizhuang Area, Qinshui Basin, Xue Haifei, Zhu Guanghui, Wang Wei, Lu Xiaoxia, Wang Minghao, Wang Yanbin

Coal Geology & Exploration

CBM fracturing effect has many influencing factors. Development effect with the same technology is different in different area. Based on a large amount of geological and engineering data in Shizhuang block, it was found that high geo-stress affects fracture extension and support in CBM fracturing, and difference between horizontal stress affects fracture direction and morphology. Coal seam with poor coal structure can produce large amount of gum during fracturing, which will block the diversion channel and result in poor fracturing effect. Engineering factors affecting fracturing effect mainly include the fracturing fluids performance, displacement, prepad fluid proportion and hole enlargement ratio. …


Corrosion Behavior Analysis Of Sucker Rod For Coalbed Methane Wells In The Eastern Block Of Ordos Basin, Pang Bin, Wang Hanxiang, Lan Wenjian Aug 2019

Corrosion Behavior Analysis Of Sucker Rod For Coalbed Methane Wells In The Eastern Block Of Ordos Basin, Pang Bin, Wang Hanxiang, Lan Wenjian

Coal Geology & Exploration

In order to make clear the corrosion rule of sucker rod for coalbed methane wells in the eastern block of Ordos basin, the paper summarizes the corrosion types and corrosion intensities of the sucker rod, based on the test of produced gas, produced water, corrosion products and weight loss of sucker rod. The paper analyzes the effect of different drainage stages, coal seam and mineralization degree of water on the corrosion. The results of the research indicate that corrosion is mainly caused by CO2 and H2S originated from No.5 coal seam and No.11 coal seam. The corrosion …


Shale Gas Potential Of Yanguanjie Formation And Longtan Formation In Central And Southeastern Hunan Province, Cao Taotao, Deng Mo, Liu Hu, Huang Yanran, Stefan Andrew Hurssthouse Aug 2019

Shale Gas Potential Of Yanguanjie Formation And Longtan Formation In Central And Southeastern Hunan Province, Cao Taotao, Deng Mo, Liu Hu, Huang Yanran, Stefan Andrew Hurssthouse

Coal Geology & Exploration

In order to reveal the shale gas potential and exploration direction of the marine-continental transitional shale in central and southeastern Hunan, samples were collected from the Lower Carboniferous Yanguanjie Formation and Upper Permian Longtan Formation, measurements were conducted on TOC, Rran, kerogen carbon isotope, maceral composition, X-ray diffraction, scanning electron microscopy, porosity, permeability and methane sorption capacity. The results indicate that Yanguanjie Formation and Longtan Formation shale are at the mature stage, and mainly dominated by type Ⅲ kerogen. The Longtan shale generally has higher TOC content, while Yanguanjie shale has usually low TOC content. The minerals are …


Application Of Seismic Exploration Technology In Forecasting Unconventional Gas Enrichment Area Of Coal Measures, Wang Shuwei Aug 2019

Application Of Seismic Exploration Technology In Forecasting Unconventional Gas Enrichment Area Of Coal Measures, Wang Shuwei

Coal Geology & Exploration

For forecasting unconventional gas enrichment area in coal measures of eastern Ordos basin, seismic exploration was used to forecast the gas in this new field. First of all, it took the post-stack impedance inversion to forecast the lithology of the reservoir, it can get the number of sample points from the impedance threshold, and get the thickness of time by cal-culating the sampling rate, after that it can get the strata thickness by multiplying the thickness of time and the velocities of strata; second, it took the pre-stack AVO inversion to forecast the lithology gas-bearing properties of the reservoir, based …


A Method Of Random Noise Suppression Based On Compressed Sensing, Yang Liangang, Li Lingyun, Yang Yumei, Qu Yuanji, Yan Ke Aug 2019

A Method Of Random Noise Suppression Based On Compressed Sensing, Yang Liangang, Li Lingyun, Yang Yumei, Qu Yuanji, Yan Ke

Coal Geology & Exploration

With the development of high precision seismic exploration technology, the use of high fidelity methods to improve the SNR of seismic data becomes the key to denoising. Curvelet threshold method can effectively suppress random noise, but at the same time the method is easy to produce pseudo Gibbs shock phenomenon, resulting in local distortion of the signal, thus affecting the processing effect. To solve this problem, a method of seismic signal denoising based on compressing sensing(CS) is presented in this paper. The method uses the difference between sparse representation of random noise and effective signal in curvelet sparse domain to …


Structural Optimization And Simulation Analysis Of High Reliability Wire-Line Coring Drilling Tools For Submarine Drilling Rigs, Wang Jialiang, Peng Fenfei, Wan Buyan, Zhou Yun Aug 2019

Structural Optimization And Simulation Analysis Of High Reliability Wire-Line Coring Drilling Tools For Submarine Drilling Rigs, Wang Jialiang, Peng Fenfei, Wan Buyan, Zhou Yun

Coal Geology & Exploration

In order to improve the working reliability of wire-line coring drilling tools used in submarine drilling rigs, based on the particularity of submarine environment, from the aspect of improvement of the single action performance of the single action mechanism and the working reliability of the suspension mechanism, the structural optimization of the single action mechanism was carried out, the numerical simulation analysis of the suspension mechanism was conducted by using ABAQUS simulation. The results show that the improved bearing assembly structure can restrain sea water corrosion, improve the centering effect of arbor and enhance the flexibility of bearing assembly. The …


A Pipeline Robot Detection Image Enhancement Method Based On Image Fusion And Improved Threshold, Yuan Mingdao, Tan Cai, Li Yang, Xu Yunqian, Zhang Xuhui, Yang Jingxue Aug 2019

A Pipeline Robot Detection Image Enhancement Method Based On Image Fusion And Improved Threshold, Yuan Mingdao, Tan Cai, Li Yang, Xu Yunqian, Zhang Xuhui, Yang Jingxue

Coal Geology & Exploration

Pipeline robot detection technology can quickly, accurately and intuitively identify the structure and hidden functional troubles of pipeline. However, due to the restriction of the pipeline environment, the detected images have problems such as uneven illumination, low contrast and blurred details. Therefore, an enhancement technique for detected image of pipeline robot is proposed. First, the contrast limited adaptive histogram equalization(CLAHE) and homomorphic filtrate(HF) are applied to deal with the problem of uneven illumination and low contrast, and the result images of the two methods are fused. Secondly, the fusion images are transformed by the Nonsubsampled Contourlet Transform(NSCT), and the improved …


Multi-Level Governance Of Climate Change Adaptation: United Nations Negotiations And Adaptation Project Implementation In Nicaragua And Samoa, Anna E. Mcginn Aug 2019

Multi-Level Governance Of Climate Change Adaptation: United Nations Negotiations And Adaptation Project Implementation In Nicaragua And Samoa, Anna E. Mcginn

Electronic Theses and Dissertations

The rapid entry into force of the Paris Agreement reaffirmed, with certainty, that the international community would continue its efforts to mitigate greenhouse gas emissions and adapt to climate change impacts opening a new era of international cooperation on climate change. This thesis explores how both negotiations around climate change adaptation and adaptation project implementation have evolved in this post-Paris Agreement era (from adoption in December 2015 to present). Using the United Nations Framework Convention on Climate Change’s (UNFCCC) Adaptation Fund as the central lens, the chapters explore international negotiations around the Fund as well as two Adaptation Fund funded …


Our Envirome, Spring/Summer 2019, Issue 40 Aug 2019

Our Envirome, Spring/Summer 2019, Issue 40

Sustain Magazine

No abstract provided.


Plastic Pollution, Fall/Winter 2019, Issue 39.3 Aug 2019

Plastic Pollution, Fall/Winter 2019, Issue 39.3

Sustain Magazine

No abstract provided.


Plastic Pollution, Fall/Winter 2019, Issue 39.2 Aug 2019

Plastic Pollution, Fall/Winter 2019, Issue 39.2

Sustain Magazine

No abstract provided.


Plastic Pollution, Fall/Winter 2019, Issue 39 Aug 2019

Plastic Pollution, Fall/Winter 2019, Issue 39

Sustain Magazine

No abstract provided.


Do Corporate Owned Adaptive Learning Platforms Perpetuate Banking Style Learning? Integrating Technology For Activism Into Transformational Sustainability Education, Tina M. Garner Aug 2019

Do Corporate Owned Adaptive Learning Platforms Perpetuate Banking Style Learning? Integrating Technology For Activism Into Transformational Sustainability Education, Tina M. Garner

Leadership for Sustainability Education Comprehensive Papers

We live in a world that tends to be controlled by corporations. The public school system should be wary of the problems that corporate control has on education. Even though public schools should not have corporate influence, the fact remains that they do, and this perpetuates Freire's banking style learning. Through time, the corporate influence in education was through educational materials such as book sales. Since the decline of the use of books and the growth of the use of technologies, corporations have followed suit through the sales of Adaptive Learning Platforms. Through leveraging the technology which students enjoy using, …


Visualizing The Fate And Distribution Of Pahs In Spartina And Avicennia Tissues From Barataria Basin, La, Kristina Jeannette Sebastian Aug 2019

Visualizing The Fate And Distribution Of Pahs In Spartina And Avicennia Tissues From Barataria Basin, La, Kristina Jeannette Sebastian

LSU Master's Theses

During crude oil spill events, vegetation in marsh environments sequester polycyclic aromatic hydrocarbons (PAHs) from the crude oil by partitioning from the air phase through the waxy cuticle on the leaf surface. Recent studies from Macondo oil-impacted marshes have demonstrated that cycling of low molecular weight petrogenic PAHs occurs through the cuticle and other leaf tissue. At present, our understanding of how PAHs travel through the cuticle is coarse and limited by grab samples across the entire leaf, which preventing a full understanding the dynamics of PAH cycling in this environment. Multiphoton (MP) confocal microscopy visualizes the distribution of PAHs …


Coarse Root, Forest Litter, And Soil Organic Matter Contributions To Carbon Sequestration In Loblolly Pine (Pinus Taeda) Plantations In East Texas, William Wedge Aug 2019

Coarse Root, Forest Litter, And Soil Organic Matter Contributions To Carbon Sequestration In Loblolly Pine (Pinus Taeda) Plantations In East Texas, William Wedge

Electronic Theses and Dissertations

Understanding ecosystem carbon dynamics is of increasing importance with atmospheric carbon dioxide (CO2) concentrations on the rise. Land management strategies, such as land use conversion, effect ecosystem carbon cycling dynamics and can alter the quantity of carbon sequestered in vegetation and soils. In East Texas and much of the southern United States, there has been a trend of converting marginal pastureland into loblolly pine (Pinus taeda) plantations. This afforestation, like all other land use conversions, leads to a redistribution of carbon in vegetation and soil carbon sinks. In 2003, five marginal pasturelands in East Texas were afforested with loblolly pine …


Evaluation Of Biodegradability Characteristics Of Cellulose-Based Film As Per Is/Iso 14855-1, Narayan C. Saha Dr, Gaurav Madhu Dr, Diksha B. Kadu Ms Aug 2019

Evaluation Of Biodegradability Characteristics Of Cellulose-Based Film As Per Is/Iso 14855-1, Narayan C. Saha Dr, Gaurav Madhu Dr, Diksha B. Kadu Ms

Journal of Applied Packaging Research

Biodegradable polymers (especially those derived from plant sources) begin their lifecycle as renewable resources, usually in the form of starch or cellulose. In this paper, the evaluation of biodegradability of cellulose-based polymer film under controlled composting conditions as per the guidelines of IS/ISO 14855 (Part-1) standard has been described. Microcrystalline cellulose (MCC) powder was taken as positive-control polymer. The apparatus used to analyse the degree and rate of biodegradation was developed indigenously. The validation of the biodegradability testing apparatus was also performed as per the prescribed test method given in IS/ISO 14855-1.


Policy Options To Streamline The Carbon Market For Agricultural Nitrous Oxide Emissions, Meredith T. Niles, Hannah Waterhouse, Robert Parkhurst, Eileen L. Mclellan, Sara Kroopf Aug 2019

Policy Options To Streamline The Carbon Market For Agricultural Nitrous Oxide Emissions, Meredith T. Niles, Hannah Waterhouse, Robert Parkhurst, Eileen L. Mclellan, Sara Kroopf

College of Agriculture and Life Sciences Faculty Publications

The majority of emissions of nitrous oxide – a potent greenhouse gas (GHG) – are from agricultural sources, particularly nitrogen fertilizer applications. A growing focus on these emission sources has led to the development in the United States of GHG offset protocols that could enable payment to farmers for reducing fertilizer use or implementing other nitrogen management strategies. Despite the development of several protocols, the current regional scope is narrow, adoption by farmers is low, and policy implementation of protocols has a significant time lag. Here we utilize existing research and policy structures to propose an ‘umbrella’ approach for nitrogen …


Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell Aug 2019

Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell

2019 Cohort

Microgrids can take power from other energy sources and share their loads meaning there is a less reliance on diesel power generation. Wind mill power generators, solar power (for the summer) and battery storage are fantastic elements for providing consistent power in the Arctic. These power systems have been tried and proven, in all conditions, over many years. Geothermal is another green efficient way to heat homes and businesses in the Arctic. When I worked for Dome Petroleum in McKinley Bay NWT, I was fortunate to work in the most extreme winter weather the Arctic can produce. With global warming …


Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell Aug 2019

Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell

Head and Heart Posters 2019

Microgrids can take power from other energy sources and share their loads meaning there is a less reliance on diesel power generation. Wind mill power generators, solar power (for the summer) and battery storage are fantastic elements for providing consistent power in the Arctic. These power systems have been tried and proven, in all conditions, over many years. Geothermal is another green efficient way to heat homes and businesses in the Arctic. When I worked for Dome Petroleum in McKinley Bay NWT, I was fortunate to work in the most extreme winter weather the Arctic can produce. With global warming …


Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell Aug 2019

Microgrid Technology And The Arctic: Green Renewable Technology Does Relate To The Land, Gerry Dell

Learning with your Head & Heart

Microgrids can take power from other energy sources and share their loads meaning there is a less reliance on diesel power generation. Wind mill power generators, solar power (for the summer) and battery storage are fantastic elements for providing consistent power in the Arctic. These power systems have been tried and proven, in all conditions, over many years. Geothermal is another green efficient way to heat homes and businesses in the Arctic. When I worked for Dome Petroleum in McKinley Bay NWT, I was fortunate to work in the most extreme winter weather the Arctic can produce. With global warming …


Subsurface Mimo: A Beamforming Design In Internet Of Underground Things For Digital Agriculture Applications, Abdul Salam Aug 2019

Subsurface Mimo: A Beamforming Design In Internet Of Underground Things For Digital Agriculture Applications, Abdul Salam

Faculty Publications

In underground (UG) multiple-input and multiple-output (MIMO), the transmit beamforming is used to focus energy in the desired direction. There are three different paths in the underground soil medium through which the waves propagates to reach at the receiver. When the UG receiver receives a desired data stream only from the desired path, then the UG MIMO channel becomes three path (lateral, direct, and reflected) interference channel. Accordingly, the capacity region of the UG MIMO three path interference channel and degrees of freedom (multiplexing gain of this MIMO channel requires careful modeling). Therefore, expressions are required for the degree of …


Modeling Irrigation Behavior In Groundwater Systems, Timothy Foster, Nicholas Brozovic, Adrian P. Butler Aug 2019

Modeling Irrigation Behavior In Groundwater Systems, Timothy Foster, Nicholas Brozovic, Adrian P. Butler

Daugherty Water for Food Global Institute: Faculty Publications

Integrated hydro-economic models have been widely applied to water management problems in regions of intensive groundwater-fed irrigation. However, policy interpretations may be limited as most existing models do not explicitly consider two important aspects of observed irrigation decision making, namely the limits on instantaneous irrigation rates imposed by well yield and the intraseasonal structure of irrigation planning. We develop a new modeling approach for determining irrigation demand that is based on observed farmer behavior and captures the impacts on production and water use of both well yield and climate. Through a case study of irrigated corn production in the Texas …


Water Productivity In Meat And Milk Production In The Us From 1960 To 2016, Mesfin Mekonnen, C.M.U. Neale, Chittaranjan Ray, Galen E. Erickson, Arjen Y. Hoekstra Aug 2019

Water Productivity In Meat And Milk Production In The Us From 1960 To 2016, Mesfin Mekonnen, C.M.U. Neale, Chittaranjan Ray, Galen E. Erickson, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Global demand for livestock products is rising, resulting in a growing demand for feed and potentially burdening freshwater resources to produce this feed. To offset this increased pressure on water resources, the environmental performance of livestock sector should continue to improve. Over the last few decades, product output per animal and feedstuff yields in the US have improved, but before now it was unclear to what extent these improvements influenced the water productivity (WP) of the livestock products. In this research, we estimate changes in WP of animal products from 1960 to 2016. We consider feed conversion ratios (dry matter …


Effects Of Human Demand On Conservation Planning For Biodiversity And Ecosystem Services, Keri B. Watson, Gillian L. Galford, Laura J. Sonter, Insu Koh, Taylor H. Ricketts Aug 2019

Effects Of Human Demand On Conservation Planning For Biodiversity And Ecosystem Services, Keri B. Watson, Gillian L. Galford, Laura J. Sonter, Insu Koh, Taylor H. Ricketts

Rubenstein School of Environment and Natural Resources Faculty Publications

Safeguarding ecosystem services and biodiversity is critical to achieving sustainable development. To date, ecosystem services quantification has focused on the biophysical supply of services with less emphasis on human beneficiaries (i.e., demand). Only when both occur do ecosystems benefit people, but demand may shift ecosystem service priorities toward human-dominated landscapes that support less biodiversity. We quantified how accounting for demand affects the efficiency of conservation in capturing both human benefits and biodiversity by comparing conservation priorities identified with and without accounting for demand. We mapped supply and benefit for 3 ecosystem services (flood mitigation, crop pollination, and nature-based recreation) by …


Aligning Evidence Generation And Use Across Health, Development, And Environment, Heather Tallis, Katharine Kreis, Lydia Olander, Claudia Ringler, David Ameyaw, Mark E. Borsuk, Diana Fletschner, Edward Game, Daniel O. Gilligan, Marc Jeuland, Gina Kennedy, Yuta J. Masuda, Sumi Mehta, Nicholas Miller, Megan Parker, Carmel Pollino, Julie Rajaratnam, David Wilkie, Wei Zhang, Selena Ahmed, Oluyede C. Ajayi, Harold Alderman, George Arhonditsis, Ines Azevedo, Ruchi Badola, Rob Bailis, Patricia Balvanera, Emily Barbour, Mark Bardini, David N. Barton, Jill Baumgartner Aug 2019

Aligning Evidence Generation And Use Across Health, Development, And Environment, Heather Tallis, Katharine Kreis, Lydia Olander, Claudia Ringler, David Ameyaw, Mark E. Borsuk, Diana Fletschner, Edward Game, Daniel O. Gilligan, Marc Jeuland, Gina Kennedy, Yuta J. Masuda, Sumi Mehta, Nicholas Miller, Megan Parker, Carmel Pollino, Julie Rajaratnam, David Wilkie, Wei Zhang, Selena Ahmed, Oluyede C. Ajayi, Harold Alderman, George Arhonditsis, Ines Azevedo, Ruchi Badola, Rob Bailis, Patricia Balvanera, Emily Barbour, Mark Bardini, David N. Barton, Jill Baumgartner

Rubenstein School of Environment and Natural Resources Faculty Publications

Although health, development, and environment challenges are interconnected, evidence remains fractured across sectors due to methodological and conceptual differences in research and practice. Aligned methods are needed to support Sustainable Development Goal advances and similar agendas. The Bridge Collaborative, an emergent research-practice collaboration, presents principles and recommendations that help harmonize methods for evidence generation and use. Recommendations were generated in the context of designing and evaluating evidence of impact for interventions related to five global challenges (stabilizing the global climate, making food production sustainable, decreasing air pollution and respiratory disease, improving sanitation and water security, and solving hunger and malnutrition) …


The Spirulina Strategy, Singapore Management University Aug 2019

The Spirulina Strategy, Singapore Management University

Perspectives@SMU

This is an adapted version of the SMU Case, “Navigating an Eternal Ocean: EnerGaia’s Emergent Strategy in the Market for Spirulina" written by Research Fellow Ryan Merrill and Assistant Professor Simon Schillebeeckx. To see the full case, please click on the following link: https://cmp.smu.edu.sg/case/3986

EnerGaia began life trying to address nutrition issues in the developing world. The prospect of profit is testing its founder to balance both or choose one over the other


Consumer Preferences For Sustainable Rice Practices In Nigeria, Glory Esohe Okpiaifo Aug 2019

Consumer Preferences For Sustainable Rice Practices In Nigeria, Glory Esohe Okpiaifo

Graduate Theses and Dissertations

Improving the sustainability of rice production is important given its position as a global staple and its environmental footprint. The adoption of sustainable practices can generate positive externalities such as lower environmental pollution and improved working conditions for rice industry workers that could be capitalized via the design of consumer-based marketing strategies. The Sustainable Rice Platform (SRP) initiative aims at advancing the adoption of sustainable practices in rice production. We assess consumers’ perceptions of the SRP sustainability indicators using the Best-Worst Scaling approach to rank SRP sustainability attributes according to their preference shares and examine the effects of demographic characteristics …


On The Path To A Resilient Urban Food System In A Rural State: A Mixed-Method Needs Assessment Of Urban Producers And County Extension Agents In Arkansas, Catherine Elizabeth Dobbins Aug 2019

On The Path To A Resilient Urban Food System In A Rural State: A Mixed-Method Needs Assessment Of Urban Producers And County Extension Agents In Arkansas, Catherine Elizabeth Dobbins

Graduate Theses and Dissertations

This project utilized a mixed-method needs assessment approach to urban agriculture in Arkansas, a predominately-rural state. Chapter II was a qualitative study, using semi-structured, in-depth interviews, that investigated the perceptions, needs, and experiences of Arkansas urban farmers and their interactions with the University of Arkansas Division of Agriculture Cooperative Extension Service (CES). Interviews were conducted with 16 urban farmers in Northwest and Central Arkansas. The interview data revealed individualized needs based on the size, years in operation, and mission of each urban farmer interviewed. General needs were determined, such as market pricing, co-ops, and access to appropriate equipment, but generally …


Apartment Residents' Understanding Of And Satisfaction With Water Savings Devices, David Farmer Aug 2019

Apartment Residents' Understanding Of And Satisfaction With Water Savings Devices, David Farmer

Electronic Theses and Dissertations

As the human population increases, the way we use and manage our supply of drinking water becomes even more important. The purpose of this study was to determine residents’ satisfaction level of and performance rating of new water savings devices installed in their apartments. Specifically the investigation focused on ratings of shower heads, kitchen faucet aerators, bath faucet aerators, and fill valve and flapper systems.

This quantitative survey included residents at 4 apartment complexes in Tennessee using a paper questionnaire (N = 626). The participants were grouped by age, ethnicity, gender, and whether or not they had experienced both nonrestrictive …


Effect Of Hydroculture Methods On Tomato Root Morphology And Anatomy, Lia Maclellan Aug 2019

Effect Of Hydroculture Methods On Tomato Root Morphology And Anatomy, Lia Maclellan

Honors College

Three methods of hydroculture were compared for their effects on the root anatomy and morphology of tomato (Solanum lycopersicum cv. Defiant). A hydroponic deep water culture method, an ebb-flood system using expanded clay pellets as a solid medium and an aeroponic sub-mist system were compared, with a solid peat/perlite medium for control. The treatments were found to have significant effects on plant root and shoot length, as well as root and shoot biomass. Root morphology was visually distinct among treatments, and all methods of hydroculture were associated with a significant increase in vascular tissue in plant roots compared with the …