Physical Sciences and Mathematics Commons^™

About Time: Visualizing Time At Burning Man, Gordon D. Hoople, Austin Choi-Fitzpatrick, Nathaniel Parde, Diane Hoffoss, Max Mellette, Rachel Nishimura, Virginia Gutman

The STEAM Journal

About Time was a 30 foot long, 3000 pound wooden sundial that went up in flames at Burning Man 2019. The piece reflected on the role time plays in our lives. We organize our lives around time—are enslaved to time—and yet we know so little about it. Physicists and philosophers continue to grapple with deep puzzles of time—Is time a fundamental quantity, independent of human actions or observations or is it an emergent property of our perception? This installation projected time using two sundials: a horizontal dial which swept time out across the desert floor and an …

Quantitative Metrics For Mutation Testing, Amani M. Ayad

Dissertations

Program mutation is the process of generating versions of a base program by applying elementary syntactic modifications; this technique has been used in program testing in a variety of applications, most notably to assess the quality of a test data set. A good test set will discover the difference between the original program and mutant except if the mutant is semantically equivalent to the original program, despite being syntactically distinct.

Equivalent mutants are a major nuisance in the practice of mutation testing, because they introduce a significant amount of bias and uncertainty in the analysis of test results; indeed, mutants …

Bio-Inspired Learning And Hardware Acceleration With Emerging Memories, Shruti R. Kulkarni

Dissertations

Machine Learning has permeated many aspects of engineering, ranging from the Internet of Things (IoT) applications to big data analytics. While computing resources available to implement these algorithms have become more powerful, both in terms of the complexity of problems that can be solved and the overall computing speed, the huge energy costs involved remains a significant challenge. The human brain, which has evolved over millions of years, is widely accepted as the most efficient control and cognitive processing platform. Neuro-biological studies have established that information processing in the human brain relies on impulse like signals emitted by neurons called …

Electrochemical Preparation And Photocatalytic Performance Of Lanio3/Tio2 Nanotube Arrays, Cheng Gong, Ze-Yang Zhang, Si-Wan Xiang, Lan Sun, Chen-Qing Ye, Chang-Jian Lin

Journal of Electrochemistry

The LaNiO₃/TiO₂ nanotube arrays were prepared by pulse electrodeposition combined with high temperature annealing. The LaNiO₃ nanoparticles modified on the TiO₂ nanotube arrays had small particle size (< 10 nm), uniform distribution and controllable loading. Some LaNiO3 nanoparticles were deposited inside the TiO₂ nanotubes. The UV-visible absorption spectra displayed that the absorption band edge of LaNiO₃/TiO₂ nanotube arrays was obviously red-shifted as compared with that of TiO₂ nanotube arrays, and the visible light absorption was enhanced significantly. The photocatalytic degradation results of rhodamine B (RhB) under visible light showed that the LaNiO₃/TiO₂ nanotube arrays prepared by pulse electrodeposition for 500 cycles had …

Electrochemical Cycling Stability Of Polyaniline Films In Different Color Ranges, Kun Xu, Kai-Ling Zhou, Hao Wang, Jing-Bing Liu, Hui Yan

Journal of Electrochemistry

The electrochromic behaviors of polyaniline films were investigated by potential step and cyclic voltammetry coupled with UV viscosity photometer. The polyaniline films show colorful changes from pale yellow to green and then to blue. Electrochromic stability, electrochemical behavior, coloring performance, optical properties and surface formations of the produced films were studied in detail. The working electrode was the flexible PANI electrode, and the counter electrode and the reference electrode were a platinum sheet and Ag/AgCl, respectively. The in situ optical transmittance of the PANI film at 650 nm was measured using an ultraviolet-visible-near-infrared spectrophotometer (Shimadzu UV-3101PC) combining with a square …

Transient Electrochemical Surface-Enhanced Raman Spectroscopic Study In Electrochemical Reduction Of P-Nitrothiophenol, Yun Ling, Jing Tang, Guo-Kun Liu, Cheng Zong

Journal of Electrochemistry

P-nitrothiophenol (PNTP) is one of the most common probe molecules studied by surface-enhanced Raman spectroscopy (SERS). The research in electrochemical reduction behavior of PNTP will help understanding the mechanism for the nitrobenzene reduction. In this paper, we used transient electrochemical surface-enhanced Raman spectroscopy (TEC-SERS) to study the SERS of PNTP with cyclic voltammetry and chronoamperometry on gold electrodes. The results show that the TEC-SERS provide a time resolution that equals the transient electrochemical methods, and we concluded that the reaction was so quick that we did not observe the spectral information of intermediate species described in the literatures with a …

Quantitative Detection Of Levofloxacin Hydrochloride By Differential Pulse Stripping Voltammetry With Electrodeposited Bismuth Film Electrodes, Zi-Ying Guo, Zuo-Peng Li, Jiang Li, Jian-Guo Zhao, Feng Feng

Journal of Electrochemistry

In this study, differential pulse stripping voltammetry was developed for the quantitative detection of levofloxacin hydrochloride indirectly. Levofloxacin hydrochloride contains organic amine, which can be precipitated upon interaction with Zn(SCN)₄^2-. By means of differential pulse stripping voltammetry, the concentration of Zn²⁺ can be determined using an in-situ formed bismuth film electrode, which allows determining indirectly the amount of levofloxacine hydrochloride. The linearity equation, I = 1.1401c - 0.5309 with the correlative coefficient R = 0.9979, was presented in the experiment. The results showed that this approach is very sensitive, having a limitation of detection of 3.18 …

Polyaniline Coated Hollow Sulfur Prepared Using Sublimate 2,4,6-Tri(Propan-2-Yl)-1,3,5-Trioxane As Template For Sulfur Electrode, Zhang-Feng Li, Xiao-Rui Wang, Wen-Sheng Tian, Jin-Ze Yang, Ping Zhang, Li-Ping Ma, Yang Chen, Xiao-Li Cui, Zhi-Yu Jiang

Journal of Electrochemistry

An advance method for preparing polyaniline-coated hollow sulfur material using sublimate material ADD(2,4,6-tri(propan-2-yl)-1,3,5-trioxane) as a template was developed for lithium-sulfur battery. At first, the smashed ADD particles were coated by a sulfur layer through the reaction of Na₂S₂O₃ with diluted HCl. Then polyaniline layer was coated again on the surface of sulfur layer through the reaction of aniline with (NH₄)₂S₂O₈. After being dried at 60 ^oC for 12 h, the ADD in such a composite evaporated totally, and resulted in the formation of polyaniline-coated hollow sulfur …

Electrochemical Determination Of Trace Copper Ions In Drinking Water Source, Jing-Ji Peng, Hong Zheng, Yi-Song Zou, Guo-Kun Liu, Dong-Xing Yuan

Journal of Electrochemistry

Aiming at the on-site and quick safety evaluation of the dissolved trace copper ions (Cu²⁺) in drinking water source, an electrochemical detection platform was developed on the basis of the square wave anodic stripping voltammetry using the gold nanoparticles (Au NPs) modified glassy carbon electrode, where Au NPs were deposited via electrochemical cyclic voltammetry. The proposed method displayed the limit of detection as low as 1.3 μg·L^-1 in the linear range of 2 ~ 50 μg·L^-1. The proposed method was applied to the determination of Cu²⁺ in the midstream of Minjiang River, one of …

Bipolar-Membrane Electrodialysis Method To Treat Industrial High Saline Perfume Wastewater, Jian Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

Large amount of organic saline wastewater is generated from various chemical industries. The contents of organic saline wastewater are more and more complicated as they are created from different types of industries. Directly discharging the organic saline wastewater without pre-treatment can generate severe environmental problem and waste useful resources. It is necessary to use an economical method to treat the organic saline wastewater and recover the salt into useful materials to achieve resource reuse. Bipolar-membrane electrodialysis (BMED) is one of the methods that can remove salt from the wastewater and convert it into certain acid and base with higher value …

Electrochemical Behaviors Of Azopurine On Gold Electrodes, Ming-Xue Li, Hang Shi, Jia Liu, Meng Zhang, Jian-Zhang Zhou, De-Yin Wu, Zhong-Qun Tian

Journal of Electrochemistry

In this paper, we studied the electrochemical behaviors of azopurine on polished gold electrodes with cyclic voltammetry (CV). On the basis of analyzing scan rate and peak current, it was supposed that the redox process belonged to a reversible process controlled by adsorption in 0.2 mol·L^-1 PBS (pH = 4.0 ~ 10.0) solutions. The potentials of redox peaks moved more negatively with increasing pH value. This proved that the H⁺ proton has participcted in the electrochemical reaction. The further data analysis and the calculation of surface adsorption excess demonstrated that the reaction was a two-proton and two-electron process. …

Study On Electro-Sorption Of Heavy Metals And Sulfamethoxazole On Activated Carbon Fibers, Wen-Jun Zhao, Bing-Xin Jia, Ya-Nan Zhang, Jiu-Nian Guan, Jiao Qu, Ying Lu

Journal of Electrochemistry

To study the optimal removal condition, adsorption mechanism and comparative analysis of the three typical cationic pollutants, i.e., Zn(II), anionic pollutant Cr(VI) and molecular pollutant sulfamethoxazole (SMX), using self-made upflowed electro-sorption device for adsorptions of above three pollutants by modified activated carbon fiber were researched. The activated carbon fiber (ACF) was modified by hydrochloric acid. The ACF morphology and structure before and after modification were characterized by SEM, BET and FTIR. The characterization results show that the modified ACF had fewer surface impurities than the modified surface and the gully is more obvious, the specific surface area was increased by …

Electrochemical Sensor Based On Magnetic Electrode Modified With Magnetic Molecularly Imprinted Nanoparticles Immobilized Hemoglobin For Determination Of Hydrogen Peroxide, Yang Yuan, Jia-Xin Wang, Yu-Hua Cao

Journal of Electrochemistry

In this work, the surface-imprinted technique was used to prepare magnetic hemoglobin (Hb) imprinted nanoparticles, using Fe₃O₄@SiO₂ NPs as the carrier, Hb as the template molecule, and tetraethyl orthosilicate (TEOS) as the imprinted polymer monomer. The nanoparticles had a core-shell structure, with magnetic Fe₃O₄ NPs as the core and Hb imprinted polymers as the shell. Therefore, Hb could be concentrated and fixed on the surface of the magnetic imprinted nanoparticles (MMIPs NPs). Furthermore, MMIPs NPs were immobilized with chitosan (CS) on the surface of a magnetic electrode to constitute Hb enzyme-like biosensor …

Ionic Liquid Assisted Synthesis Of Porous Carbons From Rice Husk For Supercapacitors, Han-Fang Zhang, Feng Wei, Jian Sun, Meng-Ying Jing, Xiao-Jun He

Journal of Electrochemistry

It is still a challenge to prepare carbon materials with high specific surface area at low cost from renewable resources. Herein, the authors report an efficient approach to synthesize porous carbons (PCs) from rice husk with ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF₆)) as a template and an activation agent. The as-made PCs featured the high specific surface area up to 1438 m²·g^-1. As electrodes for supercapacitors, PCs showed a high specific capacitance of 256 F·g^-1 at 0.05 A·g^-1 in 6 mol·L^-1 KOH aqueous electrolyte and a good rate performance of 211 F·g …

An Aptasensor Based On Aunps/Pani/Tnts Nanocomposite For Electrochemical Detection Of Tobramycin, Yong-Ling Nong, Ni-Na Qiao, Ying Liang

Journal of Electrochemistry

A novel well-constructed electrochemical aptamer-based sensor for the detection of tobramycin was presented, using differential pulse voltammetry (DPV) as a detection technique and methylene blue（MB） as an electrochemical indicator. A glassy carbon electrode modified with a nanocomposite of Au nanoparticles/polyaniline/titania nanotubes (AuNPs/PANI/TNTs) was constructed as the electrode scaffold. The nanocomposite was characterized by transmission electron microscopy and X-ray photoelectron spectroscopy in detail. The results of cyclic voltammetry and electrochemical impedance measurements demonstrated that the AuNPs/PANI/TNTs nanocomposites can improve greatly the electron transfer on the interface. For the detection of tobramycin, the DPV results showed a linear relationship between the current …

Morphology Controlled Preparations And Electrochemical Properties Of Znco2O4 Electrode Materials For Supercapacitors, Yue-Shen Zhou, Meng Li, Shuang Wu, Zhao-Lei Li, Yan-Min Gao

Journal of Electrochemistry

In this work, hydrothermal reaction and high temperature were used to grow ZnCo₂O₄ active materials on Ni foam. The crystal stuctures and surface morphlogies of four samples were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The electrochemical performances were characterized by cyclic voltammetry (CV)、galvanostatic charge/discharge (GCD) testing and electrochemical impedance spectroscopy (EIS) on an electrochemical station. It can be seen that active materials tended to form denser stuctures with an increasing amount of NH₄F in the solution system and four different morphologies of ZnCo₂O …

Zif-67-Derived Ag/Co-Embedded N-Enriched Mesoporous Carbon For Oxygen Reduction Reaction, Zheng-Ling Di, Jing Zhu, Lei Dai, Wei Meng, Yue-Hua Li, Zhang-Xing He, Ling Wang

Journal of Electrochemistry

Nitrogen-doped porous carbon materials are considered as one of the most promising catalysts for oxygen reduction reaction (ORR). Herein, in order to further improve the activity of the nitrogen-doped porous carbon, Ag/Co bimetal is embedded into nitrogendoped porous carbon to form Ag/Co-embedded nitrogen-doped porous carbon material (AgCo@NC). The AgCo@NC was derived by the wet impregnation of Ag+ into ZIF-67 precursor, followed by chemical reduction and a subsequent pyrolysis process under Ar atmosphere at different temperatures (500 ℃, 600 ℃, 700 ℃). The morphologic characterization shows that the Ag/Co nanoparticles were successfully embedded in the mesoporous carbon framework with abundant nitrogen …

Electrochemical Properties Of Sulfur In Different Carbon Support Materials, Bo Zhang, Jia Liu, Xiao-Chen Liu, De-Jun Li

Journal of Electrochemistry

In order to investigate the effect of carbon structure on electrochemical performance of sulfur/carbon composite in lithium-sulfur battery, in this paper, sublimation sulfur was incorporated into three types of carbon materials, namely, graphene, carbon black and porous carbon. The three sulfur/carbon composites were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray diffraction (XRD) techniques, and their electrochemical performances were also studied. The results showed that the sulfur/porous carbon composite offered an initial discharge capacity of 1623.2 mA·h·g^-1 and remained 845 mA·h·g^-1 after 100 cycles. Compared with graphene and carbon black, the mesopores and micropores in porous …

Generating Energy Data For Machine Learning With Recurrent Generative Adversarial Networks, Mohammad Navid Fekri, Ananda M. Ghosh, Katarina Grolinger

Electrical and Computer Engineering Publications

The smart grid employs computing and communication technologies to embed intelligence into the power grid and, consequently, make the grid more efficient. Machine learning (ML) has been applied for tasks that are important for smart grid operation including energy consumption and generation forecasting, anomaly detection, and state estimation. These ML solutions commonly require sufficient historical data; however, this data is often not readily available because of reasons such as data collection costs and concerns regarding security and privacy. This paper introduces a recurrent generative adversarial network (R-GAN) for generating realistic energy consumption data by learning from real data. Generativea adversarial …

Protein And Polysaccharide-Based Magnetic Composite Materials For Medical Applications., Elizabeth J Bealer, Kyril Kavetsky, Sierra Dutko, Samuel Lofland, Xiao Hu

Faculty Scholarship for the College of Science & Mathematics

The combination of protein and polysaccharides with magnetic materials has been implemented in biomedical applications for decades. Proteins such as silk, collagen, and elastin and polysaccharides such as chitosan, cellulose, and alginate have been heavily used in composite biomaterials. The wide diversity in the structure of the materials including their primary monomer/amino acid sequences allow for tunable properties. Various types of these composites are highly regarded due to their biocompatible, thermal, and mechanical properties while retaining their biological characteristics. This review provides information on protein and polysaccharide materials combined with magnetic elements in the biomedical space showcasing the materials used, …

Comprehensive Evaluation Technology And Application Of Grouting Reinforcement Effect For Broken Coal And Rock Mass, Wang Xiaolei, Ji Zhigang, Luo Wenqiang

Coal Geology & Exploration

Grouting reinforcement of broken coal and rock mass plays an important role in controlling the stability of surrounding rocks, and the grouting effect detection is an important link to ensure the grouting engineering to meet the requirements. The evaluation index was quantitatively analyzed by slurry filling rate method, mechanical parameter method, segmented water injection method, geological radar method, drilling television method and core inspection method. The comprehensive evaluation form of grouting effect was put forward, and the application research was carried out. The results show:The rate of filling slurry and coring was more than 90%; After grouting, the compressive strength …

Microscopic Fabric Characteristics Of Typical Red Soft Rock In Badong Formation Under Uniaxial Compression Test, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen

Coal Geology & Exploration

Red silty mudstone and argillaceous siltstone are the representatives of special rock and soil in Badong Formation, are easy to disintegrate when encountering water. According to the uniaxial compression test of rock samples, a numerical model of medium and soft rock uniaxial compression test was established based on PFC_2D program. With the characteristics of stress-strain curve, subsection quantitative parameter calibration method was used to calibrate the microscopic parameters of soft rock samples. The adjustment method and the ratio of tangential bond strength(σ_c/τ_c) control specimen under uniaxial compression failure mode. The uniaxial compression test of silty …

Combined Cbm Production Behavior And Development Strategy Of Multiple Coal Seams In Zhijin Block, Guo Tao, Gao Xiaokang, Meng Guixi, Xiao Cui

Coal Geology & Exploration

Aiming at the problems that the CBM layers are numerous and thin, it is difficult to develop it effectively in south China, on the basis of the actual production data of CBM wells in Zhijin block, the production characteristics and the influencing factors of gas production of the directional wells for co-extraction of different seams and the horizontal wells for thin seams were analyzed, and corresponding suggestions for CBM development were put forward. The analysis indicated that the gas production of co-extraction of different seams was quite different, was influenced by the liquid-supplying capacity of formation, the height of desorbing …

Analysis Of Suitable Development Technology Of Cbm(Gas) In Guizhou, Xu Xiaoqian, Meng Yingfang, Duan Zhengpeng, Li Guohong, Li Qingsong

Coal Geology & Exploration

In recent years, technical bottlenecks have been encountered in the practice of CBM exploration and development in Guizhou Province, selecting suitable development technology is one of the key issues. Based on the background that CBM exists in thin coal seams and geological structures are complicated in Guizhou, combined with successful development and utilization of CBM, the CBM development and utilization technology suitable for complex geological conditions in Guizhou was put forward. Air drilling is recommended for drilling in Guizhou, according to different distance of thin seams, such as optical casing composite fracturing and salvageable bridge plug fracturing can be used. …

Evaluation Of Coalbed Methane Drainage Effect For Multi-Target Seams In Jincheng Region, Yang Jianchao, Li Guihong, Liu Yuhui, Li Guofu, Wang Chaoshuai, Sun Tianyu

Coal Geology & Exploration

The study of the multi-target seams drainage effect on coalbed methane wells has great value, including coal safe mining, underground gas control, determination of development technical indicators, single well production, rational division of development layer, efficient development of coalbed methane, and development of medium and long-term coalbed methane development planning. Taking Chengzhuang mine of Jincheng as an example, the sampling data of the extraction effect in the middle and late stages of development are compared with the original gas content of the adjacent wells to evaluate the extraction effect, and the main control factors affecting the drainage effect are analyzed …

Key Technology Of Drilling In-Seam Directional Borehole Of 3 000 M In Underground Coal Mine, Shi Zhijun, Dong Shuning, Yang Junzhe, Xu Chao, Hao Shijun, Li Quanxin, Chen Dianfu, Yao Ke, Liu Jianlin, Tian Dongzhuang

Coal Geology & Exploration

The pre-mining gas governance mode in Baode coal mine requires that long directional borehole of more than 3 000 m can be drilled along coal seam. In view of the existing technology and equipment, there are technical problems in the construction of ultra-long directional borehole, such as the difficulty of sliding drilling, the large hydraulic pressure consumption in inlet waterway, the limited transmission distance of wireline MWD signal, and incapability of flushing liquid recycle. The technology of friction reduction in sliding drilling based on the hydraulic thrust of DHM and the torsion penetration of the ultra-long drilling tool, the technology …

Extension Model Of Fracturing Cracks Of Translayer Horizontal Well In Roof Of Soft Coal Reservoir, Wang Zhirong, Hu Kai, Yang Jie, Chen Lingxia

Coal Geology & Exploration

In order to study the propagation rules of hydraulic fracturing crack formed by a horizontal well in roof to coal seam, taking the Permian-Carboniferous coal field in North China as an example, through the classical theory of fracture mechanics, damage mechanics and fluid mechanics, combined with field actual data, the modeling and verification of the space-time evolution law of the crack propagation distance and fracturing time were carried out. Firstly, considering the additional stress of perforation, the characteristics of primary fracture and the permeability characteristics of rock formation, the calculation formula of cracking pressure of vertical hydraulic fracture caused by …

Technology Feasibility Of Gas Drainage With Comb-Shaped Long Borehole In Floor Instead Of Translayer Borehole, Li Hong, Liu Mingju, Hao Guangsheng, Deng Qigen, Dong Yanjun

Coal Geology & Exploration

Drainage technology of translayer borehole in floor roadway and directional long hole are the most important gas control measures in high gas and outburst-prone mining face at present. The coal seam in Zhaozhuang mine has the characteristics of being soft and low gas permeability. It is difficult to drill and form holes in a coal seam. For gas control, the major method is to drill a translayer borehole to eliminate gas outburst, supplemented by in-seam gas drainage boreholes. However, there are shortcomings such as large engineering volume, long construction period and high cost of drilling in floor rock roadway. The …

An Improved Method For Characterizing Coal Metamorphism By Xrd, Wang Chao, Zhao Younan, Wang Zhenwei, Lu Zhaolin

Coal Geology & Exploration

At present, the X-ray measurement method of coal metamorphism has the problem that the γ band is not well divided, the δ peak information is not used, and the background of the bottom is unreasonable. The X-ray diffraction pattern of coal with different metamorphosed degrees is compared and studied. It is proposed to correct the metamorphic coefficient formula by using the information of the slope of the 002 peak, the extended half-height width and the δ peak without deducting the so-called background information. The calculation of the XRD patterns of coal samples with different degrees of metamorphism is verified. The …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.