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Understanding Students’ Global Interdependence In Science Instruction, Walter S. Smith 2021 Texas Tech University

Understanding Students’ Global Interdependence In Science Instruction, Walter S. Smith

Journal of Global Education and Research

Multiple American educational organizations such as the National Education Association, Association for Supervision and Curriculum Development, and the Council of Chief State School Officers have advocated for globalizing the K-12 curriculum. The National Science Teaching Association (NSTA) in a position statement on international education and the Next Generation Science Standards have produced goals and standards for internationalizing the science curriculum by addressing topics such as climate change, environment, and disease that cross borders. In contrast to those pronouncements on the curriculum, this article views global science education through an instructional lens that focuses on a students’ global interdependence in science ...


Physical Chemistry, Ruth E. Stark 2021 CUNY City College

Physical Chemistry, Ruth E. Stark

Open Educational Resources

This is a provisional syllabus for Physical Chemistry I (Thermodynamics), to be taught using an OER Textmap in Fall, 2021.


Calibration Of Gas Flow Meters Using Choked Flow And An Evacuated Vessel, Max B. Trueblood, Otmar Schmid, Nicholas Altese, Christian J. Hurst, Wenyan Liu, Teresa Gelles, Steven C. Achterberg, Philip D. Whitefield, Donald E. Hagen 2021 Missouri University of Science and Technology

Calibration Of Gas Flow Meters Using Choked Flow And An Evacuated Vessel, Max B. Trueblood, Otmar Schmid, Nicholas Altese, Christian J. Hurst, Wenyan Liu, Teresa Gelles, Steven C. Achterberg, Philip D. Whitefield, Donald E. Hagen

Chemistry Faculty Research & Creative Works

The measurement of gas flow rates is of great importance in a wide range of modern technologies. This paper introduces a simple, yet accurate technique for in-house calibration of gas FMs (mass and volumetric) even under harsh environmental conditions such as encountered during field measurement campaigns. The method requires only readily available, low cost components: a vessel of known volume, an air pump, a pressure sensor and a metal plate orifice or a needle valve to act as a CO. The unique property of choked flow in the CO is used here for flow calibration. In the method presented here ...


Vermiculations In Painted Caves: New Inputs From Laboratory Experiments And Field Observations, Perrine Freydier, Eric Weber, Jérôme Martin, Pierre-Yves Jeannin, Béatrice Guerrier, Frédéric Doumenc 2021 Université Paris-Saclay, France

Vermiculations In Painted Caves: New Inputs From Laboratory Experiments And Field Observations, Perrine Freydier, Eric Weber, Jérôme Martin, Pierre-Yves Jeannin, Béatrice Guerrier, Frédéric Doumenc

International Journal of Speleology

Vermiculations are aggregates of small particles commonly found on cave walls. They are a major concern for the conservation of painted caves, as they can potentially alter valuable prehistoric cave paintings. A previous rheological study of fine sediment deposits on cave walls revealed that this material can undergo a solid-to-liquid transition triggered by variations in the chemical composition of the water film on the wall. Such a transition could occur at the origin of vermiculations by allowing the sediment to flow under low mechanical stress. In this work, we provide quantitative information on the conditions leading to this transition and ...


Novel Pilot Development Of A Closed-Loop Sustainable System Between Biogas Renewable Energy, Distilling, And Aquaculture By Vermiculture Of Stillage Wastes, Samuel C. Kessler 2021 University of Louisville

Novel Pilot Development Of A Closed-Loop Sustainable System Between Biogas Renewable Energy, Distilling, And Aquaculture By Vermiculture Of Stillage Wastes, Samuel C. Kessler

The Cardinal Edge

This study provides a mixed-methods approach in analyzing a potential closed-loop system between renewable biogas production from anaerobic digestion, vermiculture production, aquaculture production, and organic wastes with a particular focus on stillage wastes. Such system may hold significant promise for significantly reducing organic carbon and methane emissions from its components, and should be assessed for such. The 2021 IPCC report essentially identified methane reduction as the single fastest way to slow global warming (IPCC, 2021), making the study and implementation of methane-reducing systems and supportive policy for them critical. Knowledge gaps to implementing this system were qualitatively identified as disconnect ...


Analysis Of The Electronic Effects And Reactivity Of Benzhydrols In The Formation Of Benzhydryl Ethers, Katherine Quesada, Daniel Chabeda, Jaeger Johnson, Alex Shore 2021 Yale University

Analysis Of The Electronic Effects And Reactivity Of Benzhydrols In The Formation Of Benzhydryl Ethers, Katherine Quesada, Daniel Chabeda, Jaeger Johnson, Alex Shore

The Yale Undergraduate Research Journal

Benzhydryl ethers were synthesized through the use of microwave irradiation in a proto-ionic liquid solvent. The resulting products were separated from the reaction mixture by vacuum filtration with a silica gel plug. The products were analyzed using GCMS and 1 H NMR techniques to identify and quantify products. Analysis of the resultant data indicated the syntheses of the desired benzhydryl products were successful for 4,4-dimethoxybenzhydrol (conversion: 83% (1-propyl ether), 11% (2-propyl ether), 11% (menthyl ether)) and 4,4-dimethylbenzhydrol (conversion to desired product: 100% (1-propyl ether), 100% (2-propyl ether), 26% (menthyl ether)). However, the syntheses were unsuccessful for reactant 4 ...


Spectral Analysis Of A New Electronic Transition Of Platinum Fluoride, Ptf, Carol Welch 2021 University of Missouri, St. Louis

Spectral Analysis Of A New Electronic Transition Of Platinum Fluoride, Ptf, Carol Welch

Undergraduate Research Symposium

The electronic landscape of platinum containing molecules has been the focus of numerous spectroscopic studies in recent years, because of the difficulty in describing electronic structure theoretically due to electronic correlations and relativistic effects. A collective effort by spectroscopitsts and theoreticians to investigate the diatomic molecule platinum fluoride, PtF, has included research such as developing potential energy diagrams and performing analyses on rotational transitions with microwave spectroscopy. One group observed electronic transitions of PtF using laser vaporization/reaction with jet free expansion and laser induced spectroscopy. A highly effective method for observing and analyzing electronic transitions of small, metal-containing molecules ...


An Examination Of Factors Influencing Small Proton Chemical Shift Differences In Nitrogen-Substituted Monodeuterated Methyl Groups, Stuart J. Elliott, O. Maduka Ogba, Lynda J. Brown, Daniel J. O'Leary 2021 University of Liverpool

An Examination Of Factors Influencing Small Proton Chemical Shift Differences In Nitrogen-Substituted Monodeuterated Methyl Groups, Stuart J. Elliott, O. Maduka Ogba, Lynda J. Brown, Daniel J. O'Leary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Monodeuterated methyl groups have previously been demonstrated to provide access to long-lived nuclear spin states. This is possible when the CH2 D rotamers have sufficiently different populations and the local environment is chiral, which foments a non-negligible isotropic chemical shift difference between the two CH2 D protons. In this article, the focus is on the N-CH2 D group of N-CH2 D-2-methylpiperidine and other suitable CH2 D piperidine derivatives. We used a combined experimental and computational approach to investigate how rotameric symmetry breaking leads to a 1H CH2 D chemical shift ...


Bioaccessibility And Reactivity Of Alloy Powders Used In Powder Bed Fusion Additive Manufacturing, Yolanda S. Hedberg 2021 Western University

Bioaccessibility And Reactivity Of Alloy Powders Used In Powder Bed Fusion Additive Manufacturing, Yolanda S. Hedberg

Chemistry Publications

Exposure to metal particles via the inhalation route unavoidably takes place at occupational settings during additive manufacturing of metals and alloys. This calls for investigations on possible adverse health effects. This study focuses on virgin and reused powders of three iron- and nickel-based alloy powders (316L, IN718, 18Ni300) widely used in additive manufacturing, and dust powder of 18Ni300 generated during laser melting. Investigations were performed from a physico-chemical and toxicological perspective assessing their bioaccessibility in artificial lysosomal fluid (ALF, simulating lung exposure to respirable particles), corrosion behavior, surface morphology and composition, microstructure, hydrodynamic size distribution in ALF, and in-vitro toxicity ...


Evaluation Of The Potential Of Automated Sem-Eds Analysis For The Discrimination Of Inorganic Soil Particles, Anna S. Duggar 2021 The Graduate Center, City University of New York

Evaluation Of The Potential Of Automated Sem-Eds Analysis For The Discrimination Of Inorganic Soil Particles, Anna S. Duggar

Dissertations, Theses, and Capstone Projects

Soil, that complex mixture of minerals, organic particles, chemicals, and anthropogenic materials, is ubiquitous and easily transferred, which gives it forensic relevance. Forensic soil analysis has traditionally included the identification and comparison of both organic and inorganic components, the inorganic portion being most commonly examined by light microscopy and other instrumental techniques. Predominantly, the inorganic materials in soil are naturally-occurring minerals, contributed as grains from the surrounding bedrock, which gives a soil its regional character. That parent material then undergoes physical, chemical, and anthropogenic changes producing wide geographic variation within a single region. This variation forms the basis for potential ...


Don't Sell Them Short, There's More To Bacterial Natural Products Than Antibiotics, Alison Clare Domzalski 2021 The Graduate Center, City University of New York

Don't Sell Them Short, There's More To Bacterial Natural Products Than Antibiotics, Alison Clare Domzalski

Dissertations, Theses, and Capstone Projects

Recent genomic studies of microbiomes have revealed an overwhelming number of biosynthetic genes of unknown function. Most of these “cryptic” biosynthetic genes are not expressed in laboratory monocultures of individual microbes. Thus, there remains tremendous untapped potential for natural products discovery. Here we employ mixed microbial culture (MMC) as a simple yet powerful approach to awaken cryptic biosynthetic gene clusters. Our preliminary studies demonstrated that arrays of metabolites could be induced in MMCs upon environmental cues, such as surface adhesion. Using this system, we have screened, identified, and isolated bioactive bacterial metabolites, which were characterized structurally and biologically. Of the ...


Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles 2021 The Graduate Center, City University of New York

Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles

Dissertations, Theses, and Capstone Projects

Hypersurface Photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ~1 micrometer resolution in the x, y, and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface- initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block- copolymer brush patterns. Chapter 1 will review the advances in instrumentation architectures from our group that have made these ...


Evaluation Of Wind Data Reliability By Using Logarithmic And Power Laws: A Case Study In Southern Iraq, Ahmed B. Khamees, Saif F. Yaseen, Khalid S. Heni, Mudar Ahmed Abdulsattar 2021 Ministry of Science and Technology, Renewable Energy Directorate, Iraq

Evaluation Of Wind Data Reliability By Using Logarithmic And Power Laws: A Case Study In Southern Iraq, Ahmed B. Khamees, Saif F. Yaseen, Khalid S. Heni, Mudar Ahmed Abdulsattar

Karbala International Journal of Modern Science

In this study, two sites were investigated in the southern region of Iraq: Ali AL-Gharbi and AL-Salman in Mesan and AL-Muthana provinces, respectively. A theoretical extrapolation between wind speed and height was carried out for both locations each month using the Logarithmic Law. Power Law was also applied to achieve calculations of wind shear coefficient (α) by using the actual data collected from the meteorological mast installed in each site at three levels of 10 m, 30 m, and 50 m, at an interval of ten minutes. To compare the effects of each law, two laws are employed.


Polystyrene Molecular Weight Determination Of Submicron Particles Shell, Airat Z. Sakhabutdinov Dr.Sc., Professor, Safaa.M.R.H. Hussein Graduate Student, Alsu R. Ibragimova Researcher, Ph.D., Vladimir Kuklin Lead Engineer, Ph.D., Maxim Petrovich Danilaev D.Sc., Professor, L.Y. Zaharova Chief Researcher, D.Sc. 2021 Kazan National Research Technical University

Polystyrene Molecular Weight Determination Of Submicron Particles Shell, Airat Z. Sakhabutdinov Dr.Sc., Professor, Safaa.M.R.H. Hussein Graduate Student, Alsu R. Ibragimova Researcher, Ph.D., Vladimir Kuklin Lead Engineer, Ph.D., Maxim Petrovich Danilaev D.Sc., Professor, L.Y. Zaharova Chief Researcher, D.Sc.

Karbala International Journal of Modern Science

The method of determination of the molecular weight of the polystyrene, which is formed as the shell on the surfaces of submicron aluminum oxide particles is considered in the paper. This method is based on the sedimentation of submicron particles, covered by polymer molecules, in a solvent for polystyrene. It is shown that the average polystyrene molecular weight is 39500±11250 amu, when the polymer shells on the surfaces of submicron particles (Al2O3) are formed by the vapor-phase method.


Adaptive Reconstruction Of The Heterogeneous Scan Line Etm+ Correction Technique, Heba Kh. Abbas, Salema S. Salman, Rash Awad Abtan, Anwar H. Al-Saleh, Ali A. Al-Zuky 2021 Department of Physics, College of Science for Women, University of Baghdad, Baghdad, Iraq

Adaptive Reconstruction Of The Heterogeneous Scan Line Etm+ Correction Technique, Heba Kh. Abbas, Salema S. Salman, Rash Awad Abtan, Anwar H. Al-Saleh, Ali A. Al-Zuky

Karbala International Journal of Modern Science

ETM+ is a land-imaging sensor with great and wide use in many fields, however, after May 2003, because of a technical defect in the sensor´s system scan line corrector SLC, it started giving images of earth containing black gap lines at a 22% rate. These gaps made the process of analyzing and extracting accurate information from these images difficult and complicated. Therefore, scientists have developed many techniques to remove the gap lines from all ETM+ band-images and complete the missing data. In this study, three different ETM+ time images with a 16-day interval between them were used to fill ...


Two-Dimensional Quantitative Profiling Of Cell Morphology With Serous Effusion By Unsupervised Machine Learning Analysis, Safaa Al-Qaysi Ph.D., Ding Dai MD Ph.D., Heng Hong MD Ph.D., Yuhua Wen Ph.D., X.H. Hu Ph.D. 2021 Department of Physics, East Carolina University

Two-Dimensional Quantitative Profiling Of Cell Morphology With Serous Effusion By Unsupervised Machine Learning Analysis, Safaa Al-Qaysi Ph.D., Ding Dai Md Ph.D., Heng Hong Md Ph.D., Yuhua Wen Ph.D., X.H. Hu Ph.D.

Karbala International Journal of Modern Science

Cytological evaluation of serous effusion specimens is an important part of cancer diagnosis. In this study we performed two-dimensional (2D) morphometric features and clustering analysis for development of useful techniques for identification and differentiation of malignant and begin cells in serous effusion specimens extracted from ten patients with clinical symptoms of pleural and peritoneal effusion. Our findings show that the two-dimensional (2D) morphometric features and clustering analysis are useful techniques for identification and differentiation of malignant and begin cells in serous effusion specimens, which can lead to development of new methods for rapid cells profiling in clinical application.


Modeling Vitexin And Isovitexin Flavones As Corrosion Inhibitors For Aluminium Metal, Abdullahi Muhammad Ayuba, Umaru Umar 2021 Department of Pure and Industrial Chemistry, Bayero University, Kano, Nigeria

Modeling Vitexin And Isovitexin Flavones As Corrosion Inhibitors For Aluminium Metal, Abdullahi Muhammad Ayuba, Umaru Umar

Karbala International Journal of Modern Science

Theoretically, the aluminium corrosion inhibitive performance of vitexin (VTX) and isovitexin (SVT) were evaluated with a view of establishing the mechanism of the inhibition process. Calculations which include the consideration of several global descriptors were studied to describe and correlate the reactivity of the molecules with the computed descriptors. First and second-order condensed Fukui functions were employed to analyze local reactivity parameters, while simulations involving the adsorbed molecules on Al (1 1 0) surface were conducted through quench dynamic simulations and the mechanism of physical adsorption was established with SVT relatively been a better inhibitor on Al surface than VTX.


Editorial Board, 2021 Karbala International Journal of Modern Science

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.


High Speed Impact On Graphene Composites, Giovanny A. Espitia 2021 Kennesaw State University

High Speed Impact On Graphene Composites, Giovanny A. Espitia

Symposium of Student Scholars

Since the isolation of Graphene occurred in 2004, numerous studies attempting to exploit the properties of this carbon allotrope have been conducted. Graphene exists in a 2-D manner with sp2 bonds, which provides the allotrope with great electrical, conductive, and mechanical properties. In this paper however, we will focus on the latter in order to examine the feasibility of graphene composites for bulletproof material in the military. Pure graphene sheets count with high porosity density that leads to structural defects as well as poor mechanical properties due to physical contact being sole retainer. For this reason, the selected composite is ...


Investigating The Proton Transfer Dynamics And Vibrational Spectrum Of Hydrogen Oxalate Using Driven Molecular Dynamics Simulations, Martina Kaledin, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Dalton Boutwell, Martina Kaledin 2021 Kennesaw State University

Investigating The Proton Transfer Dynamics And Vibrational Spectrum Of Hydrogen Oxalate Using Driven Molecular Dynamics Simulations, Martina Kaledin, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Dalton Boutwell, Martina Kaledin

Symposium of Student Scholars

In this computational chemistry work, we describe ab initio calculations and assignment of infrared (IR) spectra of an intramolecular H-bonding system hydrogen oxalate, C2O4H. The mechanism and dynamics of proton transfer are of fundamental importance in chemistry and biology. In C2O4H, proton transfer occurs along the non-linear path. Previous experimental studies are signaling very strong coupling between OH stretch mode and low frequency motions. We calculated IR spectra at 300 K using the direct molecular dynamics (MD) method at the MP2/ aug-cc-pVDZ level of theory and assigned the prominent spectral features using ...


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