Physical Sciences and Mathematics Commons^™

Temporal Variations Of Water Productivity In Irrigated Corn: An Analysis Of Factors Influencing Yield And Water Use Across Central Nebraska, Tony Carr, Haishun Yang, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

Water Productivity (WP) of a crop defines the relationship between the economic or physical yield of the crop and its water use. With this concept it is possible to identify disproportionate water use or water-limited yield gaps and thereby support improvements in agricultural water management. However, too often important qualitative and quantitative environmental factors are not part of aWP analysis and therefore neglect the aspect of maintaining a sustainable agricultural system. In this study, we examine both the physical and economic WP in perspective with temporally changing environmental conditions. The physical WP analysis was performed by comparing simulated maximum attainable …

Use Of Water Indices Derived From Landsat Oli Imagery And Gis To Estimate The Hydrologic Connectivity Of Wetlands In The Tualatin River National Wildlife Refuge, Debra Sue Blackmore

Dissertations and Theses

This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent …

Advances In Mobile Video Networking, Qi Wang, Guojun Wang, Chrisos Grecos, Ansgar Gerlicher

All Faculty Scholarship for the College of the Sciences

Video applications have been increasingly dominating worldwide mobile network traffic in the last years. The growing popularity of smart phones and other mobile devices, on demand and surveillance video services, multimedia social networking, the latest advances in video coding and transmission, and the significant increase in mobile network capacity have all contributed to this global phenomenon. Both challenges and opportunities have emerged in multiple research disciplines involving video signal processing, 4G such as LTE (Long Term Evolution) and even 5G mobile networks, mobile cloud computing, Big Visual Data, mobile user experience, and so on. Research in these leading-edge areas has …

Comparing Hurricane And Extratropical Storm Surge For The Mid- Atlantic And Northeast Coast Of The United States For 1979–2013, James F. Booth, H E Rieder, Y Kushnir

Publications and Research

This letter examines the magnitude, spatial footprint, and paths of hurricanes and extratropical cyclones (ETCs) that caused strong surge along the east coast of the US between 1979 and 2013. Lagrangian cyclone track information, for hurricanes and ETCs, is used to associate surge events with individual storms. First, hurricane influence is examined using ranked surged events per site. The fraction of hurricanes among storms associated with surge decreases from 20%–60% for the top 10 events to 10%–30% for the top 50 events, and a clear latitudinal gradient of hurricane influence emerges for larger sets of events. Secondly, surges on larger …

High-Resolution Signatures Of Oxygenation And Microbiological Activity In Speleothem Fluid Inclusions, Nigel Blamey, Penelope J. Boston, Laura Rosales-Lagarde

International Journal of Speleology

Speleothems frequently host “fossil” fluids that were trapped in small inclusions during growth. Such fluids may provide valuable clues to past microbial, geochemical, and climatic processes during their formation. However, one difficulty is to understand which gases represent background atmosphere and fluids within a given cave system at a particular time, and which may be the product of post-trapping residual microbial activity or abiotic chemical reactions? Do we have any hope of sorting out these differences? The success depends on a quantitative understanding of the gas composition trapped in the inclusions and an understanding of the interactions of cave mineralogy, …

The Pinchot Wire: Private Cash, Public Lands - Why The Katahdin Woods And Waters National Monument Matters, Char Miller

Pomona Faculty Publications and Research

Here’s how President Obama celebrated the National Park Service’s 100th birthday: with the stroke of his pen, he established the Katahdin Woods and Waters National Monument in Maine, one of the most innovative initiatives in U.S. environmental history. That’s because the 87,500-acre park, which encompasses some of the Pine Tree State’s most remarkable forests and waterways, is a gift of the Quimby family and comes with a $40 million endowment, a private-public partnership without parallel.

A Study Of Chemistry: For Wind Ensemble, Morgan Duff

Mahurin Honors College Capstone Experience/Thesis Projects

Many musicians have a limited understanding of chemistry, while many chemists aren't familiar with details of music theory or composition. Through the composition of a four-part musical work based entirely on several broad areas of chemistry, certain relationships have been shown between music and chemistry. Because of the overlap between certain scientific concepts and many aspects of music theory, it is possible for members of both fields to use what they already know in order to gain a deeper understanding of the other, very different, subject. Because everyone has learning strengths in differing areas, I believe the use of disciplinary …

Enhancement Of Hopping Conductivity By Spontaneous Fractal Ordering Of Low-Energy Sites, Tianran Chen, Brian Skinner

Physics & Engineering Faculty Publications

Variable-range hopping conductivity has long been understood in terms of a canonical prescription for relating the single-particle density of states to the temperature-dependent conductivity. Here we demonstrate that this prescription breaks down in situations where a large and long-ranged random potential develops. In particular, we examine a canonical model of a completely compensated semiconductor, and we show that at low temperatures hopping proceeds along self-organized, low-dimensional subspaces having fractal dimension d = 2. We derive and study numerically the spatial structure of these subspaces, as well as the conductivity and density of states that result from them. One of our …

A Landscape Approach To Determining And Predicting Juvenile Coho Salmon (Oncorhynchus Kisutch) Movement Timing And Growth Patterns Prior To Ocean Entry, Amelia Lee Johnson

Dissertations and Theses

Coho salmon (Oncorhynchus kisutch) rely on unique habitats during the winter season, which may dictate how much individuals may grow and when migration from freshwater rearing habitat to the ocean occurs. Here I analyze movement timing and growth patterns for coho salmon through a field-based study and a literature review. For the field portion, I examined hatchery-stocked juvenile coho salmon across four stream basins in the Russian River watershed, California to determine the relative importance of climate, landscape, and fish size metrics in predicting movement and growth patterns over a winter rearing and spring smolt outmigration time period …

Representations And Models For Large-Scale Video Understanding, Du Le Hong Tran

Dartmouth College Ph.D Dissertations

In this thesis, we investigate different representations and models for large-scale video understanding. These methods include a mid-level representation for action recognition, a deep-learned representation for video analysis, a generic convolutional network architecture for video voxel prediction, and a new high-level task and benchmark of video comprehension. First, we present EXMOVES, a mid-level representation for scalable action recognition. The entries in EXMOVES representation are the calibrated outputs of a set of movement classifiers over spatial-temporal volumes of the input video. Each movement classifier is a simple exemplar-SVM trained on low-level features. Our EXMOVES requires a minimal amount of supervision while …

Chemistry And Biochemistry News, Georgia Southern University

Biochemistry, Chemistry & Physics: News & Publications (2012-2023)

• Faculty Awards for 2015-2016
• Georgia Southern's Elite 8 for REU-2016

Study On The Application Of Information Technology In Inland Maritime Supervision, Chong He

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Responsibilities Of Flag State In Monitoring Ships For The Implementation Of Bwm Convention, Shaojun Du

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

A Critical Review Of Existing Chinese Maritime Surveillance Capability : Research On Developing An Unmanned Aerial Vehicle (Uav) Maritime Surveillance System For China Msa, Ziyang Zhong

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Tianjin Port Emissions Control Area, Yongming Zhang

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

The Oil Spill Risk Assessment And Research On The Oil Pollution Emergency Plan In Cnooc(Huizhou) Logistics Base Wharf, Hui Yi

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Ship Emission Control And Onboard Management, Yongjian Yang

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Study On The Impact And Countermeasures Of Ship Oil Pollution In Port Caofeidian, Dejin Yang

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Ship Pollution Risk Assessment Of Taicang Port, Shuai Shuai

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Research On Supervision Countermeasures On Ship Sewage Pollution, Baoxing Shen

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Special Issue: Photoelectrochemistry And New Types Of Solar Cells, Chang-Jian Lin, Yong-Fang Li

Journal of Electrochemistry

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Cathode Buffer Layer For Improving Photovoltaic Performance Of Planar P-I-N Perovskite Solar Cells, Xiao-Dong Liu, Yong-Fang Li

Journal of Electrochemistry

Organic/inorganic hybrid metal halide perovskite semiconductor materials have drawn great attention for the application in solar cells in recent years because of their combined superior photoelectrical properties of inorganic semiconductors (with high dielectric constant and high charge carriers mobility) and organic semiconductors (with good solution processability and high absorbance). The power conversion efficiency (PCE) of the organometal halide perovskite solar cells (pero-SCs) based on CH₃NH₃PbI₃ has been increased dramatically in a few years from 3.8% to a certified 22.1%, primarily owing to the development of new interfacial materials, careful optimization of morphology, and perovskite crystallization …

Application Of Metal-Organic Frameworks In Dye-Sensitized Solar Cells, Ya-Feng Li, Qing-Qing Sun, Ming-Deng Wei

Journal of Electrochemistry

To assemble dye-sensitized solar cells (DSSCs) with high efficiencies, their photoanodes should have large specific surface area to establish a large adsorption amount of dyes and good light-harvesting ability. From this point of view, it will be an interesting topic to explore the application of metal-organic frameworks (MOFs) in the field of DSSCs due to their huge specific surface area. This paper introduces the application of MOFs in photovoltaic devices briefly, and then summaries our approaches in using MOFs in the study of DSSCs, including the pre-treatment and the post-treatment of photoanode, the preparation of photoanode materials and the light …

Fabrications Of Three Copper Sulfide Counter Electrodes And Their Influences On Photovoltaic Properties In Qdsscs, Xiao-Dan Hong, Zi-Jie Xu, Fa-Yin Zhang, Yu-Peng Li, Mei-Dan Ye, Chang-Jian Lin, Wen-Xi Guo

Journal of Electrochemistry

Quantum dot-sensitized solar cells (QDSSCs) have attracted intensive attention in scientific and industrial fields due to their high molar extinction coefficient, spectral tunability by particle size, ease of fabrication, and low cost. In the past years, semiconductor metal sulfides have attracted extensive attention because of their attractive physical and chemical properties for potential applications in many fields,such as PbS, CuS, CoS and CdS. In particular, copper sulfides have become a promising candidate for counter electrode materials in QDSSCs for their outstanding electrochemical and catalytic properties. In order to explore more stable and efficient copper sulfide counter electrode materials, in this …

Photoelectrochemical Water Splitting Cells: Methods For Improving Performance Of Electrodes And Recent Progress On Photocathodes, Kai-Jian Zhu, Wen-Jun Luo, Zhong-Jie Guan, Xin Wen, Zhi-Gang Zou, Wei Huang

Journal of Electrochemistry

Photoelectrochemical water splitting can convert solar energy into hydrogen which is an ideal way to utilize and store solar energy. A p-n tandem cell is considered as the most promising solar water splitting cell due to its high theory conversion efficiency, low cost and photoelectrode material flexibility. However, solar conversion efficiency of a tandem cell is still low in the experiment because of poor performance in a single photoelectrode. In this review, we have introduced some effective approaches to improve the performances of photoelectrodes by reducing recombination of photogenerated carriers in the bulk or on the surface, and suppressing back …

Theoretical Study Of Photoelectrochemical Reactions And Ec-Sers On Spr Metallic Electrodes Of Silver And Gold, Yuan-Fei Wu, Ran Pang, Meng Zhang, Jian-Zhang Zhou, Bin Ren, Zhong-Qun Tian, De-Yin Wu

Journal of Electrochemistry

At present photoelectrochemistry has received much concern back to nanostructures of noble metals from semiconductor electrodes. This is due to the surface plasmon resonance (SPR) effect of metallic nanostructures, which can effectively convert the far-field light to the near-field light and concentrate the photonic energy to the local surface area with high energy density. Thus, the different enhancement mechanisms, such as the local optical field enhancement, the formation of light generated hot carriers (hot electron-hole pairs), or the photothermal effect, have been proposed in literatures. On the basis of the SPR enhancement effect, the surface-enhanced Raman spectroscopy (SERS) can be …

Prospects Of D-Π-A Structured Porphyrins And Their Photoelectrochemical Application, Shuang-Shuang Liu, Jian-Feng Lu, Ming-Kui Wang

Journal of Electrochemistry

Porphyrins and their metalloderivatives are a class of compounds exhibiting a wide variety of interesting and highly useful properties, such as chlorophyll. Porphyrins are particularly interesting in photoelectrochemical applications due to their structural similarity to chlorophylls in natural photosynthetic systems, as well as their strong and tunable absorption properties. Recently, various porphyrins have been extensively studied for their applications in solar cells, photocatalytic hydrogen production, optical information storage and others. This review will focus on the unique physical and chemical properties of D-π-A structured porphyrins, and their photovoltaic performances in dye-sensitized solar cells. A brief discussion in the future development …

Preparations And Photoelectrochemical Properties Of Phosphate Modified Rgo-Biobr Nanocomposites, Shuang-Ying Chen, Zhi-Jun Li, Xu-Liang Zhang, Kang Hu, Rui Yan, Li-Qiang Jing

Journal of Electrochemistry

The RGO-BiOBr nanocomposites have been successfully synthesized by a hydrothermal process, and then modified with phosphorous acids. The photoelectrochemical properties of the fabricated RGO-BiOBr nanocomposite films were studied. The results indicate that the photocurrent densities of RGO-BiOBr were much larger compared with those of the bare BiOBr, and interestingly, the photocurrent densities were further improved after phosphate modification. Based on the analyses of the produced hydroxyl radical amounts, the enhanced photocurrent densities could be attributed to the introduction of RGO and to the formed negative fields of modified phosphate groups, which are favorable for electrons to be transferred and for …

Solvent Effect On The Anticorrosive Properties And Active Coating Area Of A Long Alkyd Varnish, Saadawy M., Abd-El-Nabey B.A., Gomaa A.Z., Ashour M.

Journal of Electrochemistry

The effects of solvent nature and composition on the anticorrosive properties of a long alkyd varnish after different days of immersion in 0.5 mol•L^-1 NaCl were studied using electrochemical impedance spectroscopy. The protection efficiencies of the long alkyd varnishes containing different solvents increased with increasing the volatility of solvent or the composition of a given volatile solvent, which was confirmed with the observations using scanning electron microscopy and energy-dispersive X-Ray spectroscopy. The delaminated area, the area where the organic coating is detached from the metal surface leaving it unprotected, was found to decrease by increasing the volatility of solvent.

Activation Effect Of Nano-Carbon Derived From Co2 On Lead Electrode In Sulfuric Aqueous Solution, Yu-Qiao Song, Hua Zhu, Guang-Jin Zhao, Wen-Long Wu, Shou-Bin Zhou, Di-Hua Wang

Journal of Electrochemistry

Serious sulfation of the negative plate is one of the most popular reasons of the early failure of lead-acid battery. Addition of nano-carbon was proved to be effective for recovering the sulfated electrode and the property of the carbon material always plays an important role. In this work, a new kind of nano-carbon material with high electrical conductivity and good adsorption capability for heavy metal cations, which is electrochemically prepared from CO₂ in molten carbonates, was tested as activation additive for the sulfated lead electrode by cyclic voltammetry and SEM measurements. The results showed that the as-prepared carbon can …