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International Journal of Nuclear Security

No abstract provided.

Nuclear Power: Black Sky Liability Or Black Sky Asset?, Sherrell R. Greene

International Journal of Nuclear Security

Ready access to abundant electricity is a key enabler of modern life. During the past decade the vulnerability of Critical Infrastructure sectors in the U.S. to a variety of natural hazards and man-made threats has become increasingly apparent. The electrical infrastructure (the “Grid”) is the foundation for all other critical civil infrastructures upon which our society depends. Therefore, protection of the Grid is an energy security, homeland security, and national security issue of highest importance. Geomagnetic disturbances (GMD) induced by solar coronal mass ejections (CMEs), electromagnetic pulse (EMP) attacks, and cyber attacks are three events having the potential to plunge …

Student Competition Cover

International Journal of Nuclear Security

No abstract provided.

Improving Nuclear Safety, Security, And Nonproliferation In Northeast Asia Through Multinational Approach, Viet Phuong Nguyen

International Journal of Nuclear Security

No abstract provided.

Prospects For Cooperation On Tackling Nuclear And Radiological Terrorism In South Asia: India–Pakistan Nuclear Detection Architecture, Muhammad Umer Khan

International Journal of Nuclear Security

No abstract provided.

Modern Advancements In Post-Detonation Nuclear Forensic Analysis, S. Adam Stratz, Jonathan A. Gill, John D. Auxier Ii, Howard L. Hall

International Journal of Nuclear Security

Deterring nuclear terrorism is a critical national asset to support the preclusion of non-state actors from initiating a nuclear attack on the United States. Successful attribution of a detonated nuclear weapon allows for timely responsive measures that prove essential in the period following a nuclear event. In conjunction with intelligence and law enforcement evidence, the technical nuclear forensics (TNF) post-detonation community supports this mission through the development and advancement of expertise to characterize weapon debris through a rapid, accurate, and detailed approach. Though the TNF field is young, numerous strides have been made in recent years toward a more robust …

Evaluation Of Covert Plutonium Production From Unconventional Uranium Sources, Ondrej Chvala, Steven Skutnik, Tyrone Christopher Harris, Emily Anne Frame

International Journal of Nuclear Security

The potential for a relatively non-advanced nation to covertly acquire a significant quantity of weapons-grade plutonium using a gas-cooled, natural uranium-fueled reactor based on relatively primitive early published designed is evaluated in this article. The economic and technical issues that would influence the design decisions of a covert ²³⁹Pu production program are considered.

Several unconventional uranium acquisition approaches were explored. Methods for extracting uranium from enrichment tails, seawater, and coal ash sources were considered. The evaluation indicated that uranium extraction from coal ash or insitu leaching from underground deposits could be performed in economical manner that might be difficult …

Janus Realized: The Use Of Social Media As A Means Of Transparency Nuclear Communication To The Public, Frances Bachstein

International Journal of Nuclear Security

No abstract provided.

Addressing The Tunnel Threat At Nuclear Facilities: A Case Study, Md. Mobasher Ahmed

International Journal of Nuclear Security

No abstract provided.

Letter From The Editor

International Journal of Nuclear Security

No abstract provided.

Electrocatalytic Valorization Of Biomass Intermediates Via 1st-Row Transition Metal Electrocatalysts, Yujie Sun

Funded Research Records

No abstract provided.

Ph-Dependent Fluorescent Probe That Can Be Tuned For Cysteine Or Homocysteine, Yongkang Yue, Fangjun Huo, Xiaoqi Li, Ying Wen, Tao Yi, James C. Salamanca, Jorge O. Escobedo, Robert Strongin, Caixia Yin

Chemistry Faculty Publications and Presentations

The very close structural similarities between cysteine and homocysteine present a great challenge to achieve their selective detection using regular fluorescent probes, limiting the biological and pathological studies of these two amino thiols. A coumarin-based fluorescent probe was designed featuring pH-promoted distinct turn-on followed by ratiometric fluorescence responses for Cys and turn-on fluorescence response for Hcy through two different reaction paths. These specific responses demonstrate the activity differences between Cys and Hcy qualitatively for the first time. The probe could also be used for Cys and Hcy imaging in living cells.

Potency And Properties Of Hydrazide Compounds That Inhibit The Growth Of Mycobacterium Tuberculosis, Ronald Bartzatt

Chemistry Faculty Publications

Aims: To examine the properties of hydrazide compounds shown to inhibit Mycobacterium tuberculosis. To identify properties that affect efficiency of bacterial inhibition.

Study Design: Utilizing data from previous studies of compounds that inhibit Mycobacterium tuberculosis, then statistical and pattern recognition methods are applied to identify interrelationships.

Place and Duration of Study: Department of Chemistry, Durham Science Center, University of Nebraska at Omaha, from January 2016 to July 2016.

Methodology: Interrelationships of pharmacological properties were identified by use of various pattern recognition techniques, such as hierarchical cluster analysis and path analysis. Molecular properties and descriptors for all compounds were …

Special Issue On Interfacial Electrochemistry, Bing-Wei Mao

Journal of Electrochemistry

Interfacial electrochemistry is an area of electrochemical science featuring investigations on structures and properties of electrode-electrolyte interfaces at which diverse electrode processes take place. With rapid development of energy sciences, understanding the roles of complex electrochemical interfaces in energy electrochemical processes becomes increasingly important, while development and employment of in-situ and ex-situ techniques to characterize the interfacial structure and property, as well as their correlation are indispensible. This special issue emphasizes on lithium-based batteries, electrocatalysis and ionic liquid electrochemistry, and comprises nine papers, including seven research articles and two review articles, which reflect the latest progresses in fundamental and applied …

Lithium-Sulfur (Selenium) Batteries: Interface Issues And Solving Strategies, Nian-Wu Li, Ya-Xia Yin, Yu-Guo Guo

Journal of Electrochemistry

The stable interface is still a challenge for lithium-sulfur (selenium) batteries because of the low conductivity of sulfur (selenium), dissolution of polysulfide (polyselenide), volume expansion of sulfur (selenium), and lithium dendrite growth. This review describers some recent developments in lithium-sulfur (selenium) batteries and highlights our efforts in this field. The possible strategies for building stable interface in the lithium-sulfur (selenium) batteries including nano-restriction effect, chemical bonding, interface adsorption, surface coating, electrolyte optimization, and Lithium anode treatment have been discussed.

Syntheses Of Ag@Pd@Pt Nanoparticles With Tunable Shell Thickness For Electrochemical Oxidation Of Formic Acid, Xiao-Dong Lin, Du-Hong Chen, Zhong-Qun Tian

Journal of Electrochemistry

In an effort to lower cost of a catalyst, the silver (Ag) core with palladium (Pd) layer then platinum (Pt) island (Ag@Pd@Pt) nanoparticles were synthesized and the electrocatalytic activity of Ag@Pd@Pt nanoparticles on formic acid was compared with that of Au@Pd@Pt nanoparticles reported previously. The results showed that the existence of a small amount of Pt could significantly improve the activity of the catalyst. When the surface coverage of Pt approached 0.5 monolayers, the activity of Ag@Pd@Pt nanoparticles reached the maximum. Though the onset potential of the electro-oxidation was slightly more positive (about 50 mV), the overall electrocatalytic activity of …

Intrinsic Interfacial Property Between High-Voltage Lini0.5Mn1.5O4 Cathode And Electrolyte, Li Li, Jing-Jing Xu, Shao-Jie Han, Wei Lu, Li-Wei Chen

Journal of Electrochemistry

To obtain high energy density, developing high-voltage cathode materials is an effective approach. The cathode/electrolyte interface stability is the key factor for the cycle performance and safety performance of high-voltage lithium ion batteries. It is, therefore, of significant importance to study the stability of cathode/electrolyte interface. However, many reports have shown that at the cathode/electrolyte interface the cathodes were prepared by coating the mixture of active materials with a conductive additive and a binder on an Al current collector. The introduction of additives will interfere the surface morphology and component analyses, resulting in difficulty to acquire the intrinsic information at …

Lithium Plating Identification From Degradation Behaviors Of Lithium-Ion Cells, Jian-Bo Zhang, Lai-Suo Su, Xin-Yu Li, Hao Ge, Ya-Kun Zhang, Zhe Li

Journal of Electrochemistry

Lithium plating has huge impact on the lifetime and safety of lithium-ion cells. It is, therefore, necessary to identify lithium plating. In this study, the accelerated stress tests of lithium-ion cells were conducted under different conditions with multi-stress loads. Based on the different effects of the two major aging mechanisms, namely, SEI (Solid Electrolyte Interface) layer growth and lithium plating, on the degradation behaviors, two lithium plating identification methods of resistance-capacity plot and Arrhenius plot were employed. The experimental results revealed that the two identification methods are highly consistent with each other. Furthermore, the origins of capacity loss were distinguished …

Stm Investigation Of Oxygen Reduction Reaction On Solid Interface In Fuel Cell, Zhen-Feng Cai, Bing Sun, Wen-Jie Jiang, Ting Chen, Dong Wang, Li-Jun Wan

Journal of Electrochemistry

An electrocatalyst for oxygen reduction reaction (ORR) is an important component for fuel cells. An investigation at interfacial electrochemical reactions toward ORR at a molecular scale benefits mechanistic understanding as well as rational design of catalysts. Scanning tunneling microscopy (STM) has been proven to be a powerful tool to monitor chemical reactions and to provide in-situ information about the interfacial electrochemical reactions at a molecular level. This review summarizes the recent STM studies in monitoring the interface processes such as morphological changes, molecular changes, reaction intermediates, and oxidation products. The prospects of future development in this field are outlined.

A Study On The Oxidation Of Hydrogen Peroxide At Au(111) And Au(100) Electrodes, Yong-Li Zheng, Jie Wei, Yan-Xia Chen

Journal of Electrochemistry

The oxidation reactions of hydrogen peroxide (H₂O₂) at Au(111) and Au(100) electrodes in 0.1 mol·L^-1 HClO₄ were investigated by using rotating disk electrode system. It was found that H₂O₂ could be readily oxidized to O₂ at both Au(100) and Au(111) surfaces with the onset potential close to its equilibrium potential. In contrast, the onset overpotential for H₂O₂ reduction was above 0.4 V, while the onset overpotential for H₂O₂ oxidation at Au(100) was ca. 0.1 V more negative than that at Au(111), this is probably …

Hydrogen Evolution Properties On Individual Mos2 Nanosheets, Yu Gao, Juan Zhou, Yu-Wen Liu, Sheng-Li Chen

Journal of Electrochemistry

Molybdenum disulfide (MoS₂) has been acknowledged to play important roles in hydrogen evolution reaction (HER) for hydrogen energy technology. Both computational and experimental results have suggested that the promising catalytic activity of MoS₂ for the HER could be attributed to the sulfur edges of two-dimensional nanosheets, while their basal planes were catalytically inert. In order to verify this conclusion, we prepared single MoS₂ sheet electrodes which were made of individual MoS₂ sheets attached on the self-assembly monolayers (SAM) of SH(CH₂)₁₅COOH at Au ultramicroelectrodes (Au/SAM/MoS₂). The single MoS₂ sheet …

Electrochemical Behaviors And Determinations Of Terbutaline Sulfate At Poly Eriochrome Black T Modified Electrode, Yan-Jie Zheng, Hong Yao, Shao-Huang Weng, Hua-Ping Peng, Shi-Wen Gong, Li Huang, Qiang Dai, Xin-Hua Lin

Journal of Electrochemistry

The poly eriochrome black T modified electrode was prepared by electropolymerization. This modified electrode was characterized by scanning electron microscopy(SEM), electrochemical impedance spectroscopy(EIS) and cyclic voltammetry (CV). The electrochemical behaviors of terbutaline sulfate were studied by CV, while the recoveries were measured by differential pulse voltammetry (DPV). The modified electrode shows excellent electrocatalytic characteristics for terbutaline sulfate. In pH 7.0 phosphate buffer solution, the oxidation peak currents obtained by DPV were linear to the terbutaline sulfate concentrations over the range of 1.2x10^-7~2.0x10^-6 mol•L^-1. The detection limit was estimated to be 1.5x10^-8 mol•L^-1 and …

Chitosan/Nonahydrate Gel Derived Fe-N-Doped Porous Carbon Sheet As High-Efficient Orr Electrocatalyst, Fan-Lu Meng, Xin-Bo Zhang, Jun-Min Yan

Journal of Electrochemistry

The chitosan/nonahydrate gel was used as a precursor to realize the uniform mixture of N-polymer and metal salt. After lyophilization treatment, the gel went through heat treatment and acid etch. Accordingly, the Fe-N-doped porous carbon sheet with homogenous composition and microstructure was prepared. Compared with the commercial Pt/C catalyst, the Fe-N-doped porous carbon sheet exhibited more positive onset potential and half-wave potential, higher current density, and especially, excellent durability. The power density of 318 mW·cm^-2 was obtained in alkaline fuel cell with the Fe-N-doped porous carbon sheet as a cathode catalyst, which is higher than 267 mW·cm^-2 with …

Synthesis Of Ultrathin Co3O4 Nanoflakes Film Material For Electrochemical Sensing, Hui-Juan Wang

Journal of Electrochemistry

Ultrathin cobalt oxide (Co₃O₄ ) nanoflakes film material was synthesized by using an electro-deposited cobalt layer as a raw material through a simple oxidation method and followed by a heat treatment at 350 ^oC. The physical characterizations of the Co₃O₄ nanoflakes film were performed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM) technologies, and the electrochemical activity was measured by cyclic voltammetry (CV). As a promising material for electrochemical sensing, the as-synthesized ultrathin Co₃O₄ nanoflakes film material exhibited excellent electrochemical activity for H₂O …

An Stm Study On The Structure Of Pt(100)/Ionic Liquid Omipf6 Interface, Jin Peng, Mian-Gang Li, Li-Qiang Xie, Jia-Wei Yan, Bing-Wei Mao

Journal of Electrochemistry

Potential-dependent structures of Pt(100)/ionic liquid 1-methyl-3-octylimidazolium hexafluorophosphate (OMIPF₆) interface have been studied by electrochemical scanning tunneling microscopy (ECSTM). The cation OMI⁺ forms ordered structure on Pt(100) surface, which exists in a potential region of about 1.2 V. When the potential is more negative than -0.6 V, it can be seen that the ordered structure transforms to disordered structure. When the potential shifts positively to +0.6 V, the desorption of cations OMI⁺ occurs, which indicates that strong electrostatic repulsion is needed to overcome chemical interaction between OMIPF6 and Pt(100) surface, leading to the desorption. The above results …

Investigation On Laser Induced Deposition Of Cu-Based Materials At [Bmim]Bf4/Pt Electrode Interface, Min-Min Xu, Jin-Hua Mei, Jian-Lin Yao, Ren-Ao Gu

Journal of Electrochemistry

By controlling the negative potential, Cu-based materials were deposited at the [BMIm]BF₄/Pt electrode interface under the laser irradiation. The effects of laser power and irradiation time on the yield of deposition products were studied by using different laser powers and different irradiation time. The product yield could be directly determined by the size of deposition point through the observation from the optical microscope. Further mechanism study combined with the formula deduced that the thermal effect of the laser could make the electrode surface temperature rise 110 degrees, which can promote the occurrence of electrodeposition. By SEM characterization, the …

Legal And Regulatory Framework Of Nuclear Security In Indonesia, Dahlia Cakrawati Sinaga

International Journal of Nuclear Security

Nuclear security is one of the most important topics for regulatory purposes in Indonesia. Nuclear security measures exist to prevent, detect, and respond to unauthorized removal of radioactive material and the sabotage of nuclear and radiation facilities. Indonesia participates in bilateral and multilateral cooperation and international events such as the Nuclear Security Summit. Indonesia has also ratified several international instruments related to nuclear security. Based on commitment to international events and ratification, Indonesia has developed nuclear security infrastructures by strengthening legislation and regulation, enhancing building capacity, and strengthening equipment and facilities. Badan Pengawas Tenaga Nuklir (BAPETEN) is Indonesia’s nuclear energy …

Modified Fault Tree Method For Vulnerability Analysis Of Nuclear Medicine Facility Security System Case Study: Radiotherapy Facility, Sardjito General Hospital, Haryono Budi Santosa

International Journal of Nuclear Security

Assessing the vulnerability of physical protection systems (PPS) in nuclear medicine facilities is needed to prevent a security incident that could lead to the malicious use of nuclear material. Theft and sabotage of nuclear materials is becoming globally recognized. The current methods of assessing vulnerability tend to be oriented toward complex nuclear security; consequently, it is excessive to use such methods in simple facilities (i.e., radiotherapy facilities in hospitals).

The fault tree analysis is a method to assess vulnerability for a simple nuclear facility. The method’s primary events (i.e., basic events and undeveloped events) are able to accommodate fault causes …

Nuclear Security Culture And Batan’S Assessment: Batan’S Experience, Anhar R. Antariksawan

International Journal of Nuclear Security

Organizations should increase safety to minimize the harmful effects of nuclear materials. Additionally, organizations should take measures to protect security culture within the organization itself. This paper covers the National Nuclear Energy Agency of Indonesia’s (BATAN’s) promotion of nuclear security culture and self- assessment projects, which is based on the International Atomic Energy Agency’s (IAEA) methodology.

Opportunities And Challenges In Developing Nuclear Security In Africa, James Larkin Mfr

International Journal of Nuclear Security

Those involved in nuclear security recognize that regions of significant instability in Africa have an impact on the safety and security of the continent's nuclear material and un-enriched uranium; however, some countries outside of continental Africa have taken counterproductive approaches to this issue. Despite challenges, the nuclear security community continues to develop and apply appropriate levels of nuclear security where needed. The community also takes every opportunity to make significant contributions to the global discourse on nuclear security culture.