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Probing The Extragalactic Mid-Infrared Background With Hawc, A. Albert, R. Alfaro, C. Alvarez, J. C. Arteaga-Velázquez, D. Avila Rojas, H. A.Ayala Solares, R. Babu, E. Belmont-Moreno, K. S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, O. Chaparro-Amaro, U. Cotti, J. Cotzomi, S. Coutiño De León, E. De La Fuente, R. Diaz Hernandez, M. A. Duvernois, M. Durocher, J. C. Diaz-Velez, K. Engel, C. Espinoza, K. L. Fan, M. Fernandez Alonso, N. Fraija, J. A. Garcia-Gonzalez, F. Garfias, M. M. Gonzalez, J. A. Goodman, J. P. Harding, S. Hernandez, D. Huang, F. Hueyotl-Zahuantitla, P. Huntemeyer, A. Iriarte, A. Jardin-Blicq, V. Joshi, D. Kieda, W. H. Lee, J. T. Linnemann, A. L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, E. Moreno, M. Mostafa, A. Nayerhoda, L. Nellen, M. Newbold, M. U. Nisa, R. Noriega-Papaqui, N. Omodei, A. Peisker, Y. Perez Araujo, E. G. Perez-Perez, C. D. Rho, D. Rosa-Gonzalez, H. Salazar, D. Salazar-Gallegos, F. Salesa Greus, A. Sandoval, J. Serna-Franco, A. J. Smith, Y. Son, R. W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, F. Urena-Mena, L. Villasenor, Xiaojie Wang, T. Weisgarber, E. Willox, H. Zhou, C. De Leon Jul 2022

Probing The Extragalactic Mid-Infrared Background With Hawc, A. Albert, R. Alfaro, C. Alvarez, J. C. Arteaga-Velázquez, D. Avila Rojas, H. A.Ayala Solares, R. Babu, E. Belmont-Moreno, K. S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, O. Chaparro-Amaro, U. Cotti, J. Cotzomi, S. Coutiño De León, E. De La Fuente, R. Diaz Hernandez, M. A. Duvernois, M. Durocher, J. C. Diaz-Velez, K. Engel, C. Espinoza, K. L. Fan, M. Fernandez Alonso, N. Fraija, J. A. Garcia-Gonzalez, F. Garfias, M. M. Gonzalez, J. A. Goodman, J. P. Harding, S. Hernandez, D. Huang, F. Hueyotl-Zahuantitla, P. Huntemeyer, A. Iriarte, A. Jardin-Blicq, V. Joshi, D. Kieda, W. H. Lee, J. T. Linnemann, A. L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, E. Moreno, M. Mostafa, A. Nayerhoda, L. Nellen, M. Newbold, M. U. Nisa, R. Noriega-Papaqui, N. Omodei, A. Peisker, Y. Perez Araujo, E. G. Perez-Perez, C. D. Rho, D. Rosa-Gonzalez, H. Salazar, D. Salazar-Gallegos, F. Salesa Greus, A. Sandoval, J. Serna-Franco, A. J. Smith, Y. Son, R. W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, F. Urena-Mena, L. Villasenor, Xiaojie Wang, T. Weisgarber, E. Willox, H. Zhou, C. De Leon

Physics Faculty Research & Creative Works

The extragalactic background light (EBL) contains all the radiation emitted by nuclear and accretion processes in stars and compact objects since the epoch of recombination. Measuring the EBL density directly is challenging, especially in the near-to-far-infrared wave band, mainly due to the zodiacal light foreground. Instead, gamma-ray astronomy offers the possibility to indirectly set limits on the EBL by studying the effects of gamma-ray absorption in the very high energy (VHE: >100 GeV) spectra of distant blazars. The High-Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is one of the few instrument's sensitive to gamma rays with energies above 10 TeV. …


Structure And Electronic Properties Of Amorphous Strontium Titanate, Julia E. Medvedeva, Bishal Bhattarai, Ivan A. Zhuravlev, Federico Motti, Piero Torelli, Anita Guarino, Andreas Klein, Emiliano Di Gennaro, Fabio Miletto Granozio Jul 2022

Structure And Electronic Properties Of Amorphous Strontium Titanate, Julia E. Medvedeva, Bishal Bhattarai, Ivan A. Zhuravlev, Federico Motti, Piero Torelli, Anita Guarino, Andreas Klein, Emiliano Di Gennaro, Fabio Miletto Granozio

Physics Faculty Research & Creative Works

Understanding the short-range structure of an amorphous material is the first step in predicting its macroscopic properties. Amorphous strontium titanate (a-STO) presents a unique challenge due to contradictory experimental findings regarding the local oxygen environment of titanium, concluded to be either tetrahedral or octahedral. To elucidate the discrepancy, 72 models of a-STO with density ranging from the crystalline value 5.12 to 3.07g/cm3 were prepared using ab initio molecular dynamics liquid-quench simulations and characterized by extended x-ray absorption fine structure (EXAFS) for both Ti and Sr K edge. An excellent agreement between the calculated and two independent experimental EXAFS measurements demonstrates …


Classification Of Alzheimer's Disease Via Vision Transformer: Classification Of Alzheimer's Disease Via Vision Transformer, Yanjun Lyu, Xiaowei Yu, Dajiang Zhu, Lu Zhang Jun 2022

Classification Of Alzheimer's Disease Via Vision Transformer: Classification Of Alzheimer's Disease Via Vision Transformer, Yanjun Lyu, Xiaowei Yu, Dajiang Zhu, Lu Zhang

Computer Science Faculty Research & Creative Works

Deep models are powerful in capturing the complex and non-linear relationship buried in brain imaging data. However, the huge number of parameters in deep models can easily overfit given limited imaging data samples. In this work, we proposed a cross-domain transfer learning method to solve the insufficient data problem in brain imaging domain by leveraging the knowledge learned in natural image domain. Specifically, we employed ViT as the backbone and firstly pretrained it using ImageNet-21K dataset and then transferred to the brain imaging dataset. A slice-wise convolution embedding method was developed to improve the standard patch operation in vanilla ViT. …


Classification Of Teleseismic Shear Wave Splitting Measurements: A Convolutional Neural Network Approach, Yanwei Zhang, Stephen S. Gao Jun 2022

Classification Of Teleseismic Shear Wave Splitting Measurements: A Convolutional Neural Network Approach, Yanwei Zhang, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Shear wave splitting (SWS) analysis is widely used to provide critical constraints on crustal and mantle structure and dynamic models. In order to obtain reliable splitting measurements, an essential step is to visually verify all the measurements to reject problematic measurements, a task that is increasingly time consuming due to the exponential increase in the amount of data. In this study, we utilized a convolutional neural network (CNN) based method to automatically select reliable SWS measurements. The CNN was trained by human-verified teleseismic SWS measurements and tested using synthetic SWS measurements. Application of the trained CNN to broadband seismic data …


Ultrasmall Nanodiamonds: Perspectives And Questions, Shery L.Y. Chang, Philipp Reineck, Anke Krueger, Vadym Mochalin Jun 2022

Ultrasmall Nanodiamonds: Perspectives And Questions, Shery L.Y. Chang, Philipp Reineck, Anke Krueger, Vadym Mochalin

Chemistry Faculty Research & Creative Works

Nanodiamonds are at the heart of a plethora of emerging applications in areas ranging from nanocomposites and tribology to nanomedicine and quantum sensing. The development of alternative synthesis methods, a better understanding, and the availability of ultrasmall nanodiamonds of less than 3 nm size with a precisely engineered composition, including the particle surface and atomic defects in the diamond crystal lattice, would mark a leap forward for many existing and future applications. Yet today, we are unable to accurately control nanodiamond composition at the atomic scale, nor can we reliably create and isolate particles in this size range. In this …


Ultrafast Error-Bounded Lossy Compression For Scientific Datasets, Xiaodong Yu, Sheng Di, Kai Zhao, Jiannan Tian, Dingwen Tao, Xin Liang, Franck Cappello Jun 2022

Ultrafast Error-Bounded Lossy Compression For Scientific Datasets, Xiaodong Yu, Sheng Di, Kai Zhao, Jiannan Tian, Dingwen Tao, Xin Liang, Franck Cappello

Computer Science Faculty Research & Creative Works

Today's scientific high-performance computing applications and advanced instruments are producing vast volumes of data across a wide range of domains, which impose a serious burden on data transfer and storage. Error-bounded lossy compression has been developed and widely used in the scientific community because it not only can significantly reduce the data volumes but also can strictly control the data distortion based on the user-specified error bound. Existing lossy compressors, however, cannot offer ultrafast compression speed, which is highly demanded by numerous applications or use cases (such as in-memory compression and online instrument data compression). In this paper, we propose …


Carbon Nanotube Encapsulated Metal Selenide Nanostructures For Efficient Electrocatalytic Oxygen Evolution Reaction, Harish Singh, Wipula P.R. Liyanage, Manashi Nath Jun 2022

Carbon Nanotube Encapsulated Metal Selenide Nanostructures For Efficient Electrocatalytic Oxygen Evolution Reaction, Harish Singh, Wipula P.R. Liyanage, Manashi Nath

Chemistry Faculty Research & Creative Works

Nickel selenide nanowires were grown inside carbon nanotubes through in situ encapsulation via one-step chemical vapor deposition. These NiSe2@CNT nanohybrids showed excellent electrocatalytic activity for water splitting with a low overpotential of 260 mV at 10 mA cm−2, high current density, and extended stability owing to the synergistic effect between NiSe2 and CNTs.


Examining Metal Contents In Primary And Secondhand Aerosols Released By Electronic Cigarettes, Kashala Fabrice Kapiamba, Weixing Hao, Stephen Adom, Wenyan Liu, Yue-Wern Huang, Yang Wang Jun 2022

Examining Metal Contents In Primary And Secondhand Aerosols Released By Electronic Cigarettes, Kashala Fabrice Kapiamba, Weixing Hao, Stephen Adom, Wenyan Liu, Yue-Wern Huang, Yang Wang

Chemistry Faculty Research & Creative Works

The usage of electronic cigarettes (ECs) has surged since their invention two decades ago. However, to date, the health effects of EC aerosol exposure are still not well understood because of insufficient data on the chemical composition of EC aerosols and the corresponding evidence of health risks upon exposure. Herein, we quantified the metals in primary and secondhand aerosols generated by three brands of ECs. By combining aerosol filter sampling and inductively coupled plasma mass spectrometry (ICP-MS), we assessed the mass of metals as a function of EC flavoring, nicotine concentration, device power, puff duration, and aging of the devices. …


Chiral Recognition Of Hydantoin Derivatives Enabled By Tetraaza Macrocyclic Chiral Solvating Agents Using 1H Nmr Spectroscopy, Jie Wen, Lei Feng, Hongmei Zhao, Li Zheng, Pericles Stavropoulos, Lin Ai, Jiaxin Zhang Jun 2022

Chiral Recognition Of Hydantoin Derivatives Enabled By Tetraaza Macrocyclic Chiral Solvating Agents Using 1H Nmr Spectroscopy, Jie Wen, Lei Feng, Hongmei Zhao, Li Zheng, Pericles Stavropoulos, Lin Ai, Jiaxin Zhang

Chemistry Faculty Research & Creative Works

Enantiomers of a series of hydantoin derivatives were prepared from d- and l-amino acids with p-tolyl isocyanate and 3,5-bis(trifluoromethyl)phenyl isocyanate as guests for chiral recognition by 1H NMR spectroscopy. Meanwhile, several tetraaza macrocyclic compounds were synthesized as chiral solvating agents from d-phenylalanine and (1S,2S)-(+)-1,2-diaminocyclohexane. An uncommon enantiomeric discrimination has been successfully established for hydantoin derivatives, representatives of five-membered N,N-heterocycles, in the presence of tetraaza macrocyclic chiral solvating agents (TAMCSAs) 1a-1c by means of 1H NMR spectroscopy. Several unprecedented nonequivalent chemical shifts (up to 1.309 ppm) were observed in the split 1H NMR spectra. To evaluate practical applications …


Characterization Of Competing Halogen- And Hydrogen-Bonding Motifs In Simple Mixed Dimers Of Hcn And Hx (X = F, Cl, Br, And I), Morgan A. Perkins, Gregory S. Tschumper Jun 2022

Characterization Of Competing Halogen- And Hydrogen-Bonding Motifs In Simple Mixed Dimers Of Hcn And Hx (X = F, Cl, Br, And I), Morgan A. Perkins, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

This work performs the first systematic comparison of hydrogen- and halogen-bonded configurations of the HCN/HX mixed dimer, where X = F, Cl, Br, and I. Eleven different minima have been characterized for these four heterogeneous dimers near the CCSD(T) complete basis set (CBS) limit. For each complex, two different hydrogen-bonded minima were identified: the global minimum where HX acts as the hydrogen bond donor and a local minimum where HX acts as the hydrogen bond acceptor. A halogen-bonded local minimum was also identified for all but the fluorine mixed dimer. To the best of our knowledge, three of the minima …


Preparation Of Carbon Aerogels From Polymer-Cross-Linked Xerogel Powders Without Supercritical Fluid Drying And Their Application In Highly Selective Co2adsorption, Rushi U. Soni, Vaibhav A. Edlabadkar, Daniel Greenan, Parwani M. Rewatkar, Nicholas Leventis, Chariklia Sotiriou-Leventis Jun 2022

Preparation Of Carbon Aerogels From Polymer-Cross-Linked Xerogel Powders Without Supercritical Fluid Drying And Their Application In Highly Selective Co2adsorption, Rushi U. Soni, Vaibhav A. Edlabadkar, Daniel Greenan, Parwani M. Rewatkar, Nicholas Leventis, Chariklia Sotiriou-Leventis

Chemistry Faculty Research & Creative Works

Carbon aerogels are well-known materials for their high porosity and high surface areas. They are typically made from pyrolysis of carbonizable polymeric aerogels. Here, we report an alternative route to monolithic carbon aerogels starting from xerogel powders. Use of powders speeds up solvent exchanges along sol-gel processing, and xerogelling bypasses the supercritical fluid drying step that is needed for making polymeric aerogels. Overall, this alternative route results in time, energy, and materials efficiency in the fabrication of carbon aerogels. Specifically, polymer-cross-linked silica xerogel powders were prepared via free-radical surface-initiated polymerization of acrylonitrile (AN) on a suspension of silica particles derived …


Analysis Of Federated Scheduling For Integer-Valued Workloads, Marion Sudvarg, Chris Gill Jun 2022

Analysis Of Federated Scheduling For Integer-Valued Workloads, Marion Sudvarg, Chris Gill

Computer Science Faculty Research & Creative Works

In federated scheduling of parallel real-time tasks on multiprocessor systems, high-utilization tasks are allocated dedicated processors on which they execute exclusively. Several methods exist for allocating a sufficient number of processors to guarantee that each task meets its deadline. In this paper, we propose two new strategies for allocating unit-speed cores to tasks with integer workload and deadline values. The first method can be performed in constant time for each high-utilization task, given the task's total workload, critical-path length, and deadline. The second method exploits the DAG structure of high-utilization tasks, providing a potentially better schedule in pseudo-polynomial time. We …


Pattern Recognition For Steam Flooding Field Applications Based On Hierarchical Clustering And Principal Component Analysis, Na Zhang, Mingzhen Wei, Baojun Bai, Xiaopeng Wang, Jian Hao, Shun Jia Jun 2022

Pattern Recognition For Steam Flooding Field Applications Based On Hierarchical Clustering And Principal Component Analysis, Na Zhang, Mingzhen Wei, Baojun Bai, Xiaopeng Wang, Jian Hao, Shun Jia

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Steam flooding is a complex process that has been considered as an effective enhanced oil recovery technique in both heavy oil and light oil reservoirs. Many studies have been conducted on different sets of steam flooding projects using the conventional data analysis methods, while the implementation of machine learning algorithms to find the hidden patterns is rarely found. In this study, a hierarchical clustering algorithm (HCA) coupled with principal component analysis is used to analyze the steam flooding projects worldwide. The goal of this research is to group similar steam flooding projects into the same cluster so that valuable operational …


Pattern Recognition For Steam Flooding Field Applications Based On Hierarchical Clustering And Principal Component Analysis, Na Zhang, Mingzhen Wei, Baojun Bai, Xiaopeng Wang, Jian Hao, Shun Jia Jun 2022

Pattern Recognition For Steam Flooding Field Applications Based On Hierarchical Clustering And Principal Component Analysis, Na Zhang, Mingzhen Wei, Baojun Bai, Xiaopeng Wang, Jian Hao, Shun Jia

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Steam flooding is a complex process that has been considered as an effective enhanced oil recovery technique in both heavy oil and light oil reservoirs. Many studies have been conducted on different sets of steam flooding projects using the conventional data analysis methods, while the implementation of machine learning algorithms to find the hidden patterns is rarely found. In this study, a hierarchical clustering algorithm (HCA) coupled with principal component analysis is used to analyze the steam flooding projects worldwide. The goal of this research is to group similar steam flooding projects into the same cluster so that valuable operational …


Synthesis, Physicochemical Characterization, And Catalytic Evaluation Of Fe3+-Containing Ssz-70 Zeolite, Christopher M. Lew, Cong Yan Chen, Gary J. Long, Fernande Grandjean, Andrew S. Ichimura, Dan Xie, Nicolás A. Grosso-Giordano, Khetpakorn Chakarawet, Howard S. Lacheen, Kurt O. Jensen, Abraham Martinez, Alexander Katz, Bi Zeng Zhan, Stacey I. Zones Jun 2022

Synthesis, Physicochemical Characterization, And Catalytic Evaluation Of Fe3+-Containing Ssz-70 Zeolite, Christopher M. Lew, Cong Yan Chen, Gary J. Long, Fernande Grandjean, Andrew S. Ichimura, Dan Xie, Nicolás A. Grosso-Giordano, Khetpakorn Chakarawet, Howard S. Lacheen, Kurt O. Jensen, Abraham Martinez, Alexander Katz, Bi Zeng Zhan, Stacey I. Zones

Chemistry Faculty Research & Creative Works

Whereas one-dimensional, 10-membered ring zeolites are typically used for hydroisomerization, Fe3+-containing SSZ-70 (Fe-SSZ-70) shows remarkable isomerization selectivity for a zeolite containing 12- and partially blocked 14-membered rings, in addition to 10-membered rings. Fe-SSZ-70 was compared to Al3+-containing SSZ-70 (Al-SSZ-70) in constraint index and n-decane hydrocracking tests. Fe-SSZ-70 exhibited a 74% total isomer yield (64% yield of monobranched isomers and 10% cracking yield) at 85% conversion compared to 49% total isomer yield (41% yield of monobranched isomers and 36% cracking yield) for Al-SSZ-70 at the same conversion. The selectivity to isomerization is attributed to the weaker acid …


Nonoscillatory Solutions Of Higher-Order Fractional Differential Equations, Martin Bohner, Said R. Grace, Irena Jadlovská, Nurten Kılıç Jun 2022

Nonoscillatory Solutions Of Higher-Order Fractional Differential Equations, Martin Bohner, Said R. Grace, Irena Jadlovská, Nurten Kılıç

Mathematics and Statistics Faculty Research & Creative Works

This paper deals with the asymptotic behavior of the nonoscillatory solutions of a certain forced fractional differential equations with positive and negative terms, involving the Caputo fractional derivative. The results obtained are new and generalize some known results appearing in the literature. Two examples are also provided to illustrate the results.


Analysis Of Ibnr Liabilities With Interevent Times Depending On Claim Counts, Daniel J. Geiger, Akim Adekpedjou Jun 2022

Analysis Of Ibnr Liabilities With Interevent Times Depending On Claim Counts, Daniel J. Geiger, Akim Adekpedjou

Mathematics and Statistics Faculty Research & Creative Works

We extend a recently proposed stochastic loss reserving model for liabilities from incurred but not reported (IBNR) micro-level claims. We propose viewing the number of claims from an event as a measure of catastrophic severity. This view covers catastrophes with arbitrarily many classes of magnitude. Our Markovian model allows the time between disasters to depend on the previous event's level of severity. Simultaneously, we let the discount rate vary in the same manner. First, we find the moments of IBNR liabilities in our model. Then, we permit a later time horizon for IBNR claims when considered jointly with incurred and …


Artificial Atoms From Cold Bosons In One Dimension, Fabian Brauneis, Timothy G. Backert, Simeon I. Mistakidis, Mikhail Lemeshko, Hans Werner Hammer, Artem G. Volosniev Jun 2022

Artificial Atoms From Cold Bosons In One Dimension, Fabian Brauneis, Timothy G. Backert, Simeon I. Mistakidis, Mikhail Lemeshko, Hans Werner Hammer, Artem G. Volosniev

Physics Faculty Research & Creative Works

We Investigate The Ground-State Properties Of Weakly Repulsive One-Dimensional Bosons In The Presence Of An Attractive Zero-Range Impurity Potential. First, We Derive Mean-Field Solutions To The Problem On A Finite Ring For The Two Asymptotic Cases: (I) All Bosons Are Bound To The Impurity And (Ii) All Bosons Are In A Scattering State. Moreover, We Derive The Critical Line That Separates These Regimes In The Parameter Space. In The Thermodynamic Limit, This Critical Line Determines The Maximum Number Of Bosons That Can Be Bound By The Impurity Potential, Forming An Artificial Atom. Second, We Validate The Mean-Field Results Using The …


A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai Jun 2022

A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Inaccessible pore volume (IAPV) can have an important impact on the placement of gelant during in situ gel treatment for conformance control. Previously, IAPV was considered to be a constant factor in simulators, yet it lacked dynamic characterization. This paper proposes a numerical simulation model of IAPV. The model was derived based on the theoretical hydrodynamic model of gelant molecules. The model considers both static features, such as gelant and formation properties, and dynamic features, such as gelant rheology and retention. To validate our model, we collected IAPV from 64 experiments and the results showed that our model fit moderately …


Equilibrium And Dynamic Surface Tension Behavior In Colloidal Unimolecular Polymers (Cup), Ashish Zore, Peng Geng, Michael R. Van De Mark Jun 2022

Equilibrium And Dynamic Surface Tension Behavior In Colloidal Unimolecular Polymers (Cup), Ashish Zore, Peng Geng, Michael R. Van De Mark

Chemistry Faculty Research & Creative Works

Studies of the interfacial behavior of pure aqueous nanoparticles have been limited due tothe difficulty of making contaminant-free nanoparticles while also providing narrow size distribu-tion. Colloidal unimolecular polymers (CUPs) are a new type of single-chain nanoparticle with a particle size ranging from 3 to 9 nm, which can be produced free of surfactants and volatile organic contents (VOCs). CUP particles of different sizes and surface charges were made. The surface tension behavior of these CUP particles in water was studied using a maximum bubble pressure tensiometer. The equilibrium surface tension decreased with increasing concentration and the number of charges present …


State-To-State Rate Coefficients For Hcs+In Rotationally Inelastic Collisions With H2at Low Temperatures, Otoniel Denis-Alpizar, Ernesto Quintas-Sánchez, Richard Dawes Jun 2022

State-To-State Rate Coefficients For Hcs+In Rotationally Inelastic Collisions With H2at Low Temperatures, Otoniel Denis-Alpizar, Ernesto Quintas-Sánchez, Richard Dawes

Chemistry Faculty Research & Creative Works

HCS+ ions have been detected in several regions of the interstellar medium (ISM), but an accurate determination of the chemical-physical conditions in the molecular clouds where this molecule is observed requires detailed knowledge of the collisional rate coefficients with the most common colliders in those environments. In this work, we study the dynamics of rotationally inelastic collisions of HCS+ + H2 at low temperature, and report, for the first time, a set of rate coefficients for this system. We used a recently developed potential energy surface for the HCS+-H2 van der Waals complex and …


Wavelet Power And Shannon Entropy Applied To Acoustic Emission Signals For Corrosion Detection And Evaluation Of Reinforced Concrete, Jinrui Zhang, Ziye Kang, Dongshuai Hou, Biqin Dong, Hongyan Ma Jun 2022

Wavelet Power And Shannon Entropy Applied To Acoustic Emission Signals For Corrosion Detection And Evaluation Of Reinforced Concrete, Jinrui Zhang, Ziye Kang, Dongshuai Hou, Biqin Dong, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Acoustic emission (AE) signals detected from corrosion test on a steel reinforced concrete beam subjected to the coupling effects of corrosive wet-dry cycles and static load are analyzed by power spectral density, wavelet transform, and Shannon entropy. The degradation process of the corroded reinforced concrete beam can be divided into four stages on the basis of the accumulated event number (AEN). Due to the difference of material properties, steel reinforcement and concrete matrix have distinguished AE features. The time-frequency characteristics of AE signals can reflect the microstructural degradation mechanism of steel corrosion and concrete cracking. The corrosion evaluation entails investigating …


Equilibrium And Dynamic Surface Tension Behavior In Colloidal Unimolecular Polymers (Cup), Ashish Zore, Peng Geng, Michael R. Van De Mark Jun 2022

Equilibrium And Dynamic Surface Tension Behavior In Colloidal Unimolecular Polymers (Cup), Ashish Zore, Peng Geng, Michael R. Van De Mark

Chemistry Faculty Research & Creative Works

Studies of the interfacial behavior of pure aqueous nanoparticles have been limited due tothe difficulty of making contaminant-free nanoparticles while also providing narrow size distribu-tion. Colloidal unimolecular polymers (CUPs) are a new type of single-chain nanoparticle with a particle size ranging from 3 to 9 nm, which can be produced free of surfactants and volatile organic contents (VOCs). CUP particles of different sizes and surface charges were made. The surface tension behavior of these CUP particles in water was studied using a maximum bubble pressure tensiometer. The equilibrium surface tension decreased with increasing concentration and the number of charges present …


Comprehensive Review Of Polymer And Polymer Gel Treatments For Natural Gas-Related Conformance Control, Ali Al Brahim, Baojun Bai, Thomas P. Schuman Jun 2022

Comprehensive Review Of Polymer And Polymer Gel Treatments For Natural Gas-Related Conformance Control, Ali Al Brahim, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Conformance problems often exist in natural gas-related activities, resulting in excessive water production from natural gas production wells and/or excessive natural gas production from oil production wells. Several mechanical and chemical solutions were reported in the literature to mitigate the conformance problems. Among the chemical solutions, two classes of materials, namely polymer gels and water-soluble polymers, have been mostly reported. These systems have been mainly reviewed in several studies for their applications as water shutoff treatments for oil production wells. Natural gas production wells exhibit different characteristics and have different properties which could impact the performance of the chemical solutions. …


Development And Application Of A 1d Compaction Model To Understand 65 Years Of Subsidence In The San Joaquin Valley, Matthew Lees, Rosemary Knight, Ryan G. Smith Jun 2022

Development And Application Of A 1d Compaction Model To Understand 65 Years Of Subsidence In The San Joaquin Valley, Matthew Lees, Rosemary Knight, Ryan G. Smith

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

High rates of land subsidence, caused by groundwater overdraft, are resulting in millions of dollars of infrastructure damage in California's San Joaquin Valley (SJV). In recent years, the use of interferometric synthetic aperture radar (InSAR) has enabled us to substantially improve our understanding of this subsidence. However, only very occasionally have the InSAR data been integrated with a physical model of subsurface compaction. Here, we have used InSAR and other data to parameterize and calibrate a 1D compaction model. We applied our model to a study area in the SJV where we had access to the necessary information on hydraulic …


Joint Control Of Manufacturing And Onsite Microgrid System Via Novel Neural-Network Integrated Reinforcement Learning Algorithms, Jiaojiao Yang, Zeyi Sun, Wenqing Hu, Louis Steinmeister Jun 2022

Joint Control Of Manufacturing And Onsite Microgrid System Via Novel Neural-Network Integrated Reinforcement Learning Algorithms, Jiaojiao Yang, Zeyi Sun, Wenqing Hu, Louis Steinmeister

Mathematics and Statistics Faculty Research & Creative Works

Microgrid is a promising technology of distributed energy supply system, which consists of storage devices, generation capacities including renewable sources, and controllable loads. It has been widely investigated and applied for residential and commercial end-use customers as well as critical facilities. In this paper, we propose a joint state-based dynamic control model on microgrids and manufacturing systems where optimal controls for both sides are implemented to coordinate the energy demand and supply so that the overall production cost can be minimized considering the constraint of production target. Markov Decision Process (MDP) is used to formulate the decision-making procedure. The main …


A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai Jun 2022

A Novel Numerical Model Of Gelant Inaccessible Pore Volume For In Situ Gel Treatment, Jianqiao Leng, Xindi Sun, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Inaccessible pore volume (IAPV) can have an important impact on the placement of gelant during in situ gel treatment for conformance control. Previously, IAPV was considered to be a constant factor in simulators, yet it lacked dynamic characterization. This paper proposes a numerical simulation model of IAPV. The model was derived based on the theoretical hydrodynamic model of gelant molecules. The model considers both static features, such as gelant and formation properties, and dynamic features, such as gelant rheology and retention. To validate our model, we collected IAPV from 64 experiments and the results showed that our model fit moderately …


Silverrush. Xii. Intensity Mapping For Ly Α Emission Extending Over 100-1000 Comoving Kpc Around Z ∼2-7 Laes With Subaru Hsc-Ssp And Chorus Data, Shotaro Kikuchihara, Yuichi Harikane, Masami Ouchi, Yoshiaki Ono, Takatoshi Shibuya, Ryohei Itoh, Ryota Kakuma, Akio K. Inoue, Haruka Kusakabe, Kazuhiro Shimasaku, Rieko Momose, Yuma Sugahara, Satoshi Kikuta, Shun Saito Jun 2022

Silverrush. Xii. Intensity Mapping For Ly Α Emission Extending Over 100-1000 Comoving Kpc Around Z ∼2-7 Laes With Subaru Hsc-Ssp And Chorus Data, Shotaro Kikuchihara, Yuichi Harikane, Masami Ouchi, Yoshiaki Ono, Takatoshi Shibuya, Ryohei Itoh, Ryota Kakuma, Akio K. Inoue, Haruka Kusakabe, Kazuhiro Shimasaku, Rieko Momose, Yuma Sugahara, Satoshi Kikuta, Shun Saito

Physics Faculty Research & Creative Works

We conduct intensity mapping to probe for extended diffuse Lyα emission around Lyα emitters (LAEs) at z ∼2-7, exploiting very deep (∼26 mag at 5σ) and large-area (∼4.5 deg2) Subaru/Hyper Suprime-Cam narrowband (NB) images and large LAE catalogs consisting of a total of 1540 LAEs at z = 2.2, 3.3, 5.7, and 6.6 obtained by the HSC-SSP and CHORUS projects. We calculate the spatial correlations of these LAEs with ∼1-2-billion-pixel flux values of the NB images, deriving the average Lyα surface brightness (SBLyα ) radial profiles around the LAEs. By carefully estimating systematics such as fluctuations of sky background and …


Aircraft-Engine Particulate Matter Emissions From Conventional And Sustainable Aviation Fuel Combustion: Comparison Of Measurement Techniques For Mass, Number, And Size, Joel C. Corbin, Tobias Schripp, Bruce E. Anderson, Greg J. Smallwood, Patrick Leclercq, Ewan C. Crosbie, Steven Achterberg, Philip D. Whitefield, Richard C. Miake-Lye, Zhenhong Yu, Andrew Freedman, Max B. Trueblood, David Satterfield, Wenyan Liu May 2022

Aircraft-Engine Particulate Matter Emissions From Conventional And Sustainable Aviation Fuel Combustion: Comparison Of Measurement Techniques For Mass, Number, And Size, Joel C. Corbin, Tobias Schripp, Bruce E. Anderson, Greg J. Smallwood, Patrick Leclercq, Ewan C. Crosbie, Steven Achterberg, Philip D. Whitefield, Richard C. Miake-Lye, Zhenhong Yu, Andrew Freedman, Max B. Trueblood, David Satterfield, Wenyan Liu

Chemistry Faculty Research & Creative Works

Sustainable aviation fuels (SAFs) have different compositions compared to conventional petroleum jet fuels, particularly in terms of fuel sulfur and hydrocarbon content. These differences may change the amount and physicochemical properties of volatile and non-volatile particulate matter (nvPM) emitted by aircraft engines. In this study, we evaluate whether comparable nvPM measurement techniques respond similarly to nvPM produced by three blends of SAFs compared to three conventional fuels. Multiple SAF blends and conventional (Jet A-1) jet fuels were combusted in a V2527-A5 engine, while an additional conventional fuel (JP-8) was combusted in a CFM56-2C1 engine. We evaluated nvPM mass concentration measured …


Natural Layered Mercury Antimony Sulfosalt Livingstonite With Anisotropic Optical Properties, Ravi P.N. Tripathi, Jie Gao, Xiaodong Yang May 2022

Natural Layered Mercury Antimony Sulfosalt Livingstonite With Anisotropic Optical Properties, Ravi P.N. Tripathi, Jie Gao, Xiaodong Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Naturally occurring layered mineral livingstonite is identified as a new type of van der Waals (vdW) heterostructure based 2D material, consisting of two commensurately modulated alternating layers of HgSb2S4 and Sb2S4. The heterostructures of livingstonite crystal are prepared as thin flakes via mechanical exfoliation method. The prepared livingstonite crystals are further investigated in the context of vibrational, linear, and nonlinear optical properties, including anisotropic Raman scattering, wavelength-dependent linear dichroism (LD) transition effect, birefringence, and anisotropic third-harmonic generation (THG). Owing to the monoclinic crystal structure, livingstonite crystals exhibit strong anisotropic vibrational and optical responses. In contrast to conventional vdW heterostructures, the …