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Articles 68431 - 68460 of 302499

Full-Text Articles in Physical Sciences and Mathematics

Restoring The Biodiversity Of The Roggeveld‐Renosterveld: Evaluation, Multiplication And Establishment Of Indigenous Plant Species On Old Agricultural Fields, J. C. Botha, C. F. Cupido, N. Visser Oct 2020

Restoring The Biodiversity Of The Roggeveld‐Renosterveld: Evaluation, Multiplication And Establishment Of Indigenous Plant Species On Old Agricultural Fields, J. C. Botha, C. F. Cupido, N. Visser

IGC Proceedings (1993-2023)

No abstract provided.


Effects Of Slope And Defoliation Intensity On The Effectiveness Of Desert Wheatgrass For Reduced Runoff And Soil Erosion Under Simulated Rainfall, Haitao Zuo, Juying Wu Oct 2020

Effects Of Slope And Defoliation Intensity On The Effectiveness Of Desert Wheatgrass For Reduced Runoff And Soil Erosion Under Simulated Rainfall, Haitao Zuo, Juying Wu

IGC Proceedings (1993-2023)

No abstract provided.


The Cause Of Grassland Desertification And Its Managing Strategies In Inner Mongolia, P. R. China (Session: A6), Zhaorigetu Chen, Hasibagan, Yuhai Bao, Mary Ann Rankin Oct 2020

The Cause Of Grassland Desertification And Its Managing Strategies In Inner Mongolia, P. R. China (Session: A6), Zhaorigetu Chen, Hasibagan, Yuhai Bao, Mary Ann Rankin

IGC Proceedings (1993-2023)

No abstract provided.


Seedling Recruitment In Steppe Communities, Na Zhao, Kun Wang, Zengwen Wang Oct 2020

Seedling Recruitment In Steppe Communities, Na Zhao, Kun Wang, Zengwen Wang

IGC Proceedings (1993-2023)

No abstract provided.


Perceiving Mathematics And Art, Edmund Harriss Oct 2020

Perceiving Mathematics And Art, Edmund Harriss

Mic Lectures

Mathematics and art provide powerful lenses to perceive and understand the world, part of an ancient tradition whether it starts in the South Pacific with tapa cloth and wave maps for navigation or in Iceland with knitting patterns and sunstones. Edmund Harriss, an artist and assistant clinical professor of mathematics in the Fulbright College of Arts and Sciences, explores these connections in his Honors College Mic lecture.


Polarization And Cross Section Of Midrapidity J/Ψ Production In P+P Collisions At √S=510  Gev, Mike Daugherity, Donald Isenhower, Rusty Towell Oct 2020

Polarization And Cross Section Of Midrapidity J/Ψ Production In P+P Collisions At √S=510  Gev, Mike Daugherity, Donald Isenhower, Rusty Towell

Engineering and Physics

The PHENIX experiment has measured the spin alignment for inclusive J/ψ→e+e− decays in proton-proton collisions at √s=510  GeV at midrapidity. The angular distributions have been measured in three different polarization frames, and the three decay angular coefficients have been extracted in a full two-dimensional analysis. Previously, PHENIX saw large longitudinal net polarization at forward rapidity at the same collision energy. This analysis at midrapidity, complementary to the previous PHENIX results, sees no sizable polarization in the measured transverse momentum range of 0.0


Human Rights And Social, Economic, & Environmental Justice: Ethics Of Samfundssind & Agape, Claire L. Dente Oct 2020

Human Rights And Social, Economic, & Environmental Justice: Ethics Of Samfundssind & Agape, Claire L. Dente

Sustainability Research & Practice Seminar Presentations

No abstract provided.


Evidence For Target Outer-Shell Excitation Mediated By Electron Correlation In Single-Electron-Capture Collisions Of Slow He²⁺ Ions With Ar Atoms, Z. Y. Song, X. C. Wang, Z. W. Li, K. L. Han, Daniel Fischer Oct 2020

Evidence For Target Outer-Shell Excitation Mediated By Electron Correlation In Single-Electron-Capture Collisions Of Slow He²⁺ Ions With Ar Atoms, Z. Y. Song, X. C. Wang, Z. W. Li, K. L. Han, Daniel Fischer

Physics Faculty Research & Creative Works

We have performed kinematically complete experiments on single-electron capture in slow He2+-Ar collisions. Besides the pure capture to the He+ (n = 2) level, capture into the deep He+ ( n= 1) state with simultaneous excitation of another target electron is also observed. In contrast to the pure capture, the total cross section for this two-electron transition decreases with increasing collision energy, and its angular-differential cross section exhibits a much slighter slope. We take these observations as evidence for electron capture mediated by electron-electron interactions.


A Model For The Anodic Carbonization Of Alkaline Polymer Electrolyte Fuel Cells, Qi-Hao Li, Ying-Ming Wang, Hua-Long Ma, Li Xiao, Gong-Wei Wang, Jun-Tao Lu, Lin Zhuang Oct 2020

A Model For The Anodic Carbonization Of Alkaline Polymer Electrolyte Fuel Cells, Qi-Hao Li, Ying-Ming Wang, Hua-Long Ma, Li Xiao, Gong-Wei Wang, Jun-Tao Lu, Lin Zhuang

Journal of Electrochemistry

The alkaline polymer electrolyte fuel cell (APEFC) has made appreciable progress in recent years but is still suffering performance loss during discharge with air as the oxidant. Several theories have been suggested to interpret the loss. However, efforts are still needed to reach a clear quantitative understanding. Based on the major experimental findings in combination with thermodynamics and kinetics of the reactions involved in the anode, this paper presents a model featuring layered carbonization in the anode and relevant grouped equations. The simulation results generated from the latter are compared with experiments, and possible principles to suppress the performance loss …


Research Progress Of Sulfur Cathode Catalytic Conversions For Lithium-Sulfur Batteries, Qin-Jun Shao, Jian Chen Oct 2020

Research Progress Of Sulfur Cathode Catalytic Conversions For Lithium-Sulfur Batteries, Qin-Jun Shao, Jian Chen

Journal of Electrochemistry

The electrochemical reduction of sulfur (S) takes place through multistep reactions when S is used as a cathode material. The complete discharge of S to form final product lithium sulfide (Li2S) is a two-electron reaction. The formation of low-order lithium polysulfides (LiPS) needs to overcome certain energy barriers. And the reduction of Li2S2 to Li2S is the rate-limited step. The reaction kinetic of sulfur cathode is the critical key to determine the electrochemical performance of Li-S batteries, such as specific energy, specific power and low temperature performance, etc. Accelerating the rate-limited step kinetics …


Facile Synthesis Of Nitrogen-Doped Graphene-Like Active Carbon Materials For High Performance Lithium-Sulfur Battery, Quan-Hua Meng, Wen-Wen Deng, Chang-Ming Li Oct 2020

Facile Synthesis Of Nitrogen-Doped Graphene-Like Active Carbon Materials For High Performance Lithium-Sulfur Battery, Quan-Hua Meng, Wen-Wen Deng, Chang-Ming Li

Journal of Electrochemistry

Lithium-sulphur (Li-S) battery is regarded as a promising energy storage device because of its high theoretical capacity. However, the low S utilization and short cycling life limit the commercial applications. In this work, nitrogen-doped graphene-like carbon (NGC) materials were synthesized by simply pyrolyzing and carbonizing the mixture of melamine (C3H6N6) and L-cysteine (C3H7NO2S). The graphene-like structure in NGC effectively buffered the volume change of S during the discharge/charge process and improved the cycling stability. Meanwhile, nitrogen-containing functional groups in NGC facilitated the transportation of ions and suppressed the …


Porous Electrodes In Electrochemical Energy Storage Systems, Wei-Xiao Ji, Gong-Wei Wang, Qiang Wang, Li-Jun Bai, De-Yang Qu Oct 2020

Porous Electrodes In Electrochemical Energy Storage Systems, Wei-Xiao Ji, Gong-Wei Wang, Qiang Wang, Li-Jun Bai, De-Yang Qu

Journal of Electrochemistry

Professor C.S. Cha was among the pioneers who have introduced modern electrochemistry to China. Under his leadership, the electrochemical research group in Wuhan University became one of the global powerhouses in fundamental and applied electrochemical researches. During the past many decades, Professor Cha and his colleagues in the university have educated and trained many students who have become part of the backbone of electrochemistry worldwide. In this review, we demonstrate the solid foundation laid by Professor Cha and his colleagues in Wuhan University, and the advancements made in the area of porous electrodes by the authors. All the authors in …


Progress And Prospects On Multifunctional Coating Separators For Lithium-Sulfur Battery, Zhuang-Zhuang Wei, Nan-Xiang Zhang, Feng Wu, Ren-Jie Chen Oct 2020

Progress And Prospects On Multifunctional Coating Separators For Lithium-Sulfur Battery, Zhuang-Zhuang Wei, Nan-Xiang Zhang, Feng Wu, Ren-Jie Chen

Journal of Electrochemistry

The development of advanced energy storage systems is crucial to meet the growing demand for electric vehicles, portable devices and renewable energy storage. Lithium-sulfur (Li-S) batteries, with their advantages of high specific energy, low cost of raw materials and environmental friendliness, are hotspots in the research field of new high performance batteries. However, there are still many problems which hinder the practical applications of lithium-sulfur batteries, such as the shuttle effect of soluble polysulfide intermediates, the growth of lithium dendrites, and the thermal stability and safety of lithium-sulfur batteries during use. The design of multifunctional coating separator is one of …


Electrochemical Engineering Of Carbon Nanodots, Lei Bao, Dai-Wen Pang Oct 2020

Electrochemical Engineering Of Carbon Nanodots, Lei Bao, Dai-Wen Pang

Journal of Electrochemistry

Aqueous batteries have been considered to be a competitive candidate for large-scale energy storage. However, most of aqueous batteries adopt inorganic electrode materials with metallic elements, which are based on the reversible insertion of metal ions, making their application being highly hindered by limited cycle life, environmental issue, high cost and low reserves. On the other hand, organic electrode materials offer the advantages of abundant reserves, tunable structures, renewability and environmental benignity. Furthermore, the wide internal space enables these organics to flexibly store various charge carriers. Organics have been investigated as the alternative to inorganic electrode materials. Herein, we review …


Humanistic Climate Philosophy: Erich Fromm Revisited, Nicholas Dovellos Oct 2020

Humanistic Climate Philosophy: Erich Fromm Revisited, Nicholas Dovellos

USF Tampa Graduate Theses and Dissertations

Given the current juncture in history, humanity is faced with the herculean task of adapting to a tumultuous present and a gimmer future. Should climate projections be accurate, there is little time to waste. This work makes the claim that we are not only in a political gridlock but also in an academic one. Researching climate philosophy from its inception, the concluding view is that no major progress, outside of a standardized descriptive analysis, has been achieved. Thus, the work evaluates an array of climate philosophers e.g. Stephen Gardiner, James Garvey, Peter Singer, Walter Sinnott-Armstrong, etc., with specific emphasis on …


"Authors On The Hill " Presents Prof. Giovanni Spani, Giovanni Spani Oct 2020

"Authors On The Hill " Presents Prof. Giovanni Spani, Giovanni Spani

Authors on the Hill

Professor Giovanni Spani of the World Languages, Literatures, and Cultures Department at the College of the Holy Cross will present his work on Dante's Florence, a multimedia educational app for Android and iOS.


Human Health And Wellness In Space: A Review Of Common Effects, Current Research, And Methods Of Prevention, Sonnet Xu, Rajendra Persaud, Nazrul I. Khandaker, Jasmin Budhan Oct 2020

Human Health And Wellness In Space: A Review Of Common Effects, Current Research, And Methods Of Prevention, Sonnet Xu, Rajendra Persaud, Nazrul I. Khandaker, Jasmin Budhan

Publications and Research

Space poses a threat to space crew wellness, where microgravity, isolation, radiation, and other conditions exert strain on human health. This study explores the changes to the human body in space and how it contributes to major threats to health during spaceflights. The effects of the hostile environment of outer space are all examined here, along with resultant changes to behavior, physiology, and the difficulty of remote diagnosis for health treatment in space. This review also considers the implications to the human cartilage, brain, and eyes along with the various other hazards and physiological alterations.

Human health in space is …


An Analysis Of Astrophotography: How Accurate Is The Photography Of Space?, Denice Morales, Rajendra Persaud, Nazrul I. Khandaker, Omadevi Sing, Matthew Khargie Oct 2020

An Analysis Of Astrophotography: How Accurate Is The Photography Of Space?, Denice Morales, Rajendra Persaud, Nazrul I. Khandaker, Omadevi Sing, Matthew Khargie

Publications and Research

The current research goal is to talk about astrophotography that is designed to interact with non-STEM majors in the natural sciences, and to teach future or beginner astronomers and citizen scientists. The course depends on constructivist tutorial strategies to instruct records, cut price and photo processing strategies, and at the same time address mathematical anxiety. The goal of the pathways is to create an awesome ride in the natural sciences, which has been traditionally linked to imparting pertinent education to a cohort of citizen scientists and novice astronomers - businesses which historically have analyzed an amazing volume of files (both …


Provable Security Of Symmetric-Key Cryptographic Schemes., Ashwin Jha Dr. Oct 2020

Provable Security Of Symmetric-Key Cryptographic Schemes., Ashwin Jha Dr.

Doctoral Theses

In this thesis, we provide quantitative and/or qualitative improvements in the provable security of several symmetric-key schemes, encompassing major information security goals, viz. data authentication, encryption, and authenticated encryption.AUTHENTICATION AND INTEGRITY: Among authentication schemes, we analyze the CBC-MAC family and counter-based MACs (XMACC, XMACR, PCS, LightMAC etc.), referred as the XMAC family. First, we revisit the security proofs for CBC-MAC and EMAC, and identify a critical flaw in the state-of-the-art results. We revise the security proofs and obtain significantly better bounds in case of EMAC, ECBC and FCBC. Second, we study the security of CBC-MAC family, when the underlying primitive …


Essays On Environmental And Health Economics., Prachi Singh Dr. Oct 2020

Essays On Environmental And Health Economics., Prachi Singh Dr.

Doctoral Theses

This thesis consists of three empirical essays that investigate issues in environmental and health economics. The main focus of this thesis is to study how environmental degradation or interventions in this domain can affect demographic and health outcomes of the population in developing countries. The first chapter explores the effect of an information campaign about arsenic contamination in Bangladesh on marriage market outcomes. This study finds that providing information about negative effects of arsenic consumption had an unintended consequence in the marriage market. Specifically, information about lower fertility, skin lesions, cancers and higher mortality related to arsenic exposure induced individuals …


Impacts Of Land-Use Change On The Menominee River In Jo Daviess County, Illinois, Preston J. Konop Oct 2020

Impacts Of Land-Use Change On The Menominee River In Jo Daviess County, Illinois, Preston J. Konop

Theses and Dissertations

This study addresses land-use changes in Jo Daviess County, Illinois, and their effects on the Menominee River. The Menominee River flows north to south through Jo Daviess County, and southern Grant County, Wisconsin. Many of the surrounding properties are agricultural and have undergone developmental and land-use changes that may affect the flood flashiness of the Menominee River. The concern with increasing flood flashiness of the Menominee River include more frequent flooding events, undercutting of riverbanks, and increased amounts of sediment transport from upstream locations into the Mississippi River. Increases in impermeable surfaces have led to greater amounts of runoff during …


Search For A Dark Leptophilic Scalar In E + E − Collisions, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, Milind Purohit, Et. Al. Oct 2020

Search For A Dark Leptophilic Scalar In E + E − Collisions, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, Milind Purohit, Et. Al.

Faculty Publications

Many scenarios of physics beyond the standard model predict the existence of new gauge singlets, which might be substantially lighter than the weak scale. The experimental constraints on additional scalars with masses in the MeV to GeV range could be significantly weakened if they interact predominantly with leptons rather than quarks. At an e+e collider, such a leptophilic scalar (ϕL) would be produced predominantly through radiation from a τ lepton. We report herein a search for e+e→ τ+τϕL, ϕL → l+l (l = …


Mars 2020: A Step Closer To The Red Planet, Kevin Ng, Matthew Khargie, Omadevi Singh, Sashi Singh, Nazrul I. Khandaker, Rajendra Persaud Oct 2020

Mars 2020: A Step Closer To The Red Planet, Kevin Ng, Matthew Khargie, Omadevi Singh, Sashi Singh, Nazrul I. Khandaker, Rajendra Persaud

Publications and Research

This research paper primarily focuses on the NASA Mars 2020 mission, but will also revisit and discuss past rover missions. As the Mars 2020 mission is ongoing, some information will be updated accordingly. For decades, humans have dreamed of the colonization of Mars for many reasons, such as some similarities shared by Earth and Mars or the close proximity to our planet. In fact, dozens of films, books, and articles have been written, especially in the past 2 decades, about the possibility. As technology advances, we develop newer equipment to hopefully make this possibility into a reality. Of course, placing …


Liquid Metal Electrodes For Electrochemical Energy Storage Technologies, Hao-Miao Li, Hao Zhou, Kang-Li Wang, Kai Jiang Oct 2020

Liquid Metal Electrodes For Electrochemical Energy Storage Technologies, Hao-Miao Li, Hao Zhou, Kang-Li Wang, Kai Jiang

Journal of Electrochemistry

Electrochemical energy storage technologies (ESTs) with low cost, long lifespan and high safety are of great importance for efficient integration of renewable energy into the grid. Liquid metal electrodes (LMEs) possessing the merits of high electronic conductivity, easy manufacture and amorphous structure is of great application value in the field of energy storage batteries. During charge-discharge processing, the LMEs could avoid the issues of structural deformation and dendrite growth in solid metal electrodes, which could effectively extend the cycle life of the LME based batteries. Moreover, LME based batteries are easy to be scaled up and less expensive, which are …


Cycling Performance And Solid-Electrolyte-Interphase Synergic Formation Of Silicon Nanoparticles In The Concentrated Electrolyte With Additives, Zeng-Hua Chang, Fu-Juan Han, Xi-Xin Yang, Jian-Tao Wang, Shi-Gang Lu Oct 2020

Cycling Performance And Solid-Electrolyte-Interphase Synergic Formation Of Silicon Nanoparticles In The Concentrated Electrolyte With Additives, Zeng-Hua Chang, Fu-Juan Han, Xi-Xin Yang, Jian-Tao Wang, Shi-Gang Lu

Journal of Electrochemistry

In this paper, the effects of additives on the cycling performance of silicon nanoparticles in LiFSI-(PC)3 based concentrated electrolytes were systematically studied. The structures of silicon nanoparticle electrodes and the evolution of solid-electrolyte-interphase were characterized by scanning electron microscopy (SEM), attenuated total reflection Flourier transformed infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The results indicated that the additives can efficiently improve the cycling performance of silicon nanoparticle electrodes. In LiFSI-(PC)3 concentrated electrolyte, the capacity became 574.8 mAh·g-1 after 300 cycles with the initial capacity of 3296.1 mAh·g-1. In contrast, the 3% LiDFOB, 3% FEC …


Research Progress Of Key Components In Lithium-Sulfur Batteries, Jia-Jia Chen, Quan-Feng Dong Oct 2020

Research Progress Of Key Components In Lithium-Sulfur Batteries, Jia-Jia Chen, Quan-Feng Dong

Journal of Electrochemistry

Due to the much higher theoretical specific capacity and energy density than the ones of traditional lithium ion battery, Li-S batteries have long been at the pinnacle in the realms of high-energy Li-metal batteries. However, the complicated electrochemical reactions on the sulfur cathode and Li anode, induced by the thermodynamic and kinetic behaviors of lithium polysulfides, are the intrinsic bottleneck to realize the full potential of Li-S batteries for practical application. In this review, we firstly discuss the roles, and thermodynamic and kinetic behaviors of polysulfides in the charging and discharging processes of Li-S batteries. Then, the functional design and …


Microgravity And Its Bearing With Space Flight-Related Research, Farhan Tanvir, Nazrul I. Khandaker, Rajendra Persaud, Jeff Guan Oct 2020

Microgravity And Its Bearing With Space Flight-Related Research, Farhan Tanvir, Nazrul I. Khandaker, Rajendra Persaud, Jeff Guan

Publications and Research

This study investigates the unique properties and applications of microgravity in the context of spaceflight research. Understanding and harnessing the behaviors of a microgravity environment opens up the doors to long-term space travel and consequently, future missions to other planets within our solar system. More specifically, simulating and conducting experiments in microgravity environments helps us explore its effects on the various necessary tasks and behaviors that are carried out during spaceflight. The most immediate and pronounced effects of microgravity are on human physiology. In particular, studies have shown that prolonged exposure to microgravity can result in a 20% decrease in …


Porous-Electrode Theory Of Lithium Ion Battery: Old Paradigm And New Challenge, Xiao-Xiao Wang, Zi-Rui Zhou, Qiang Shan, Zeng-Ming Zhang, Jun Huang, Yu-Wen Liu, Sheng-Li Chen Oct 2020

Porous-Electrode Theory Of Lithium Ion Battery: Old Paradigm And New Challenge, Xiao-Xiao Wang, Zi-Rui Zhou, Qiang Shan, Zeng-Ming Zhang, Jun Huang, Yu-Wen Liu, Sheng-Li Chen

Journal of Electrochemistry

A critical review on the porous electrode theory developed by Newman and his colleagues is presented. We propose several ideas for further development of this theory by analyzing its limitations. The classical Newman theory does not consider ion steric effect in describing ion transport in electrolyte solutions, which can be amended by a newly developed ion-vacancy coupled charge transfer model for ion transport in concentrated solutions. Ion transport in solid particles of active materials is essentially an ion-electron coupled transport process, and its rationality is verified by comparing the calculated and experimental diffusion coefficients of Li + ion in intercalation …


Research Progress Of High-Safety Phosphorus-Based Electrolyte, Zi-Qi Zeng, Xin-Ping Ai, Han-Xi Yang, Yu-Liang Cao Oct 2020

Research Progress Of High-Safety Phosphorus-Based Electrolyte, Zi-Qi Zeng, Xin-Ping Ai, Han-Xi Yang, Yu-Liang Cao

Journal of Electrochemistry

Lithium-ion batteries (LIBs) have emerged as the most widely used energy storage devices owing to their high energy density and excellent cycling stability. However, safety issues have become a critical obstacle for the large-scale applications of LIBs in the energy storage systems and electric vehicles (EVs). Currently, LIBs use a low flash- and boiling-point organic carbonate as the electrolyte, which is extremely likely to cause firing or explosion. Although some flame-retardant additives can inhibit the combustion of electrolyte to a certain extent, it brings little effect in practical application. Therefore, the development of nonflammable electrolytes is an essential solution to …


Preface To The Memorial Special Issue For Professor Chuansin Cha, Xin-Ping Ai, Han-Xi Yang, Lin Zhuang, Sheng-Li Chen Oct 2020

Preface To The Memorial Special Issue For Professor Chuansin Cha, Xin-Ping Ai, Han-Xi Yang, Lin Zhuang, Sheng-Li Chen

Journal of Electrochemistry

No abstract provided.