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Full-Text Articles in Physical Sciences and Mathematics

Differentiation Of Human, Dog, And Cat Hair Fibers Using Dart Tofms And Machine Learning, Laura Ahumada, Erin R. Mcclure-Price, Chad Kwong, Edgard O. Espinoza, John Santerre Dec 2023

Differentiation Of Human, Dog, And Cat Hair Fibers Using Dart Tofms And Machine Learning, Laura Ahumada, Erin R. Mcclure-Price, Chad Kwong, Edgard O. Espinoza, John Santerre

SMU Data Science Review

Hair is found in over 90% of crime scenes and has long been analyzed as trace evidence. However, recent reviews of traditional hair fiber analysis techniques, primarily morphological examination, have cast doubt on its reliability. To address these concerns, this study employed machine learning algorithms, specifically Linear Discriminant Analysis (LDA) and Random Forest, on Direct Analysis in Real Time time-of-flight mass spectra collected from human, cat, and dog hair samples. The objective was to develop a chemistry- and statistics-based classification method for unbiased taxonomic identification of hair. The results of the study showed that LDA and Random Forest were highly …

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Phosphorus And Its Role In Chemical Evolution, Asbel Gonzalez Sep 2023

Phosphorus And Its Role In Chemical Evolution, Asbel Gonzalez

PANDION: The Osprey Journal of Research and Ideas

Phosphorus is a minor element with a cosmic abundance of about 105.5 atoms per 1012 H atoms (Boudreaux, n.d.). Phosphorus was depleted as a volatile throughout the developing solar system, and as a result, volatile forms of phosphorus would have been minimal, even in the colder regions of the solar nebula. Despite its low abundance, phosphorus minerals play key roles in planetary petrology, including through the formation of phosphate minerals that trapped volatiles and rare Earth elements, and in the formation of metal phosphides that may have served as nucleation sites for kamacite and taenite crystal growth in minor planet …

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Exploring Students’ Epistemological Understanding Of Atomic Structure Models, Claire V. Ward, Morgan Balabanoff Sep 2023

Exploring Students’ Epistemological Understanding Of Atomic Structure Models, Claire V. Ward, Morgan Balabanoff

The Cardinal Edge

Developing a robust understanding of atomic structure and the nature of matter is foundational across chemistry and STEM courses. The development of this concept is challenging because it relies on models to illustrate something not directly observable. Scientific models are important tools used to explain phenomena, particularly phenomena that are not directly observable. In general chemistry, students are typically asked to consider four different models: (1) the particle model, (2) the nuclear model, (3) the Bohr model, and (4) the Quantum model. Each depiction has its own advantages and limitations, where instructors introduce each model to explain specific parts of …

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Exploring Retrieval Difficulties And Self-Confidence In An Assessment Of General Chemistry Students, Karen Julian, Morgan Balabanoff Sep 2023

Exploring Retrieval Difficulties And Self-Confidence In An Assessment Of General Chemistry Students, Karen Julian, Morgan Balabanoff

The Cardinal Edge

Developing self-assessment skills is an important aspect of learning. Framed by assessment developed for the year-long sequence of general chemistry, students were asked to rate their ability to answer conceptual questions. Using cognitive interviews, this study revealed that people rely on a range of characteristics other than content knowledge to assess their confidence, including doubt, retrieval difficulty, and test-taking methods. These findings imply that more explicit instruction may be required to encourage correct self-assessment. Students can develop their metacognitive skills and calibrate their perceived ability by completing examinations meant to emphasize content knowledge gaps.

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Principles Of Chemistry-1, Rajnish Singh Feb 2023

Principles Of Chemistry-1, Rajnish Singh

KSU Distinguished Course Repository

Principles of Chemistry, chem 1211, is a 3 credit hour course, the first in a two-semester sequence covering the fundamental principles and applications of chemistry for science majors. Course content includes electronic structure of atoms and molecules, bonding fundamentals, fundamentals of chemical reactions, and gas laws. The course is taught asynchronously and the final exam being a national exam offered by the American chemical society, (ACS), that has to be taken in person.

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Geothermal Energy And Its Impacts On The Environment, Aditi Gorthy, Nathan Tran, Laureen Pierre-Louis Jan 2023

Geothermal Energy And Its Impacts On The Environment, Aditi Gorthy, Nathan Tran, Laureen Pierre-Louis

Mako: NSU Undergraduate Student Journal

From the multitude of energy sources that we have developed throughout the eons, renewable energy or “clean energy” has been on the rise to combat global warming and climate change which burning nonrenewable sources of energy have contributed to. Before geothermal energy is used as part of the mainstream energy sources some aspects must be analyzed and resolved. Unfortunately, geothermal power plants still release pollutants, such as carbon dioxide and sulfur dioxide, into the environment and cause general environmental disruptions due to drilling and changes in land formations. Recent and future studies have been and should be conducted to find …

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Novel Technique In Production Of Pb (Ii)- Imprinted Polymers, Ehab Mohammed, Mostafa M. Elsheikh, Adham A. El-Zomrawy, Farag A. Ahmed Jan 2023

Novel Technique In Production Of Pb (Ii)- Imprinted Polymers, Ehab Mohammed, Mostafa M. Elsheikh, Adham A. El-Zomrawy, Farag A. Ahmed

Al-Azhar Bulletin of Science

Ion imprinting techniques were used to produce ion imprinted polymer (IIP) particles for the selective removal of Pb2+ from aqueous environments. As the Templating monomers, acrylic acid, acrylic amine ligand, and Methylene Bisacrylamide crosslinker were chosen. The imprinted polymer was prepared by free radical polymerization. By leaching with 0.1 M HCl, the (Pb2+) ion was removed from the template. The polymer particles were characterized by IR spectroscopy, Thermal analysis and potentiometric analysis. The produced polymer was mechanically crushed into fine particles, assembled into a sensor probe, and linked to a bare HB graphite pencil electrode (GPE). The sensor has a …

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Synthesis Of New Ligand-Based Phosphazo Ring And Its Transition Metal Complexes As Cancer Inhibitor: Spectroscopic, Dft, Antimicrobial, And Molecular Docking Investigations, Asmaa A. Hamed, Ahmed A. El-Sherif, Carmen M. Sharaby, Yousry A. Ammar, Mona F. Amine Jan 2023

Synthesis Of New Ligand-Based Phosphazo Ring And Its Transition Metal Complexes As Cancer Inhibitor: Spectroscopic, Dft, Antimicrobial, And Molecular Docking Investigations, Asmaa A. Hamed, Ahmed A. El-Sherif, Carmen M. Sharaby, Yousry A. Ammar, Mona F. Amine

Al-Azhar Bulletin of Science

A condensation between 2-sulfanilamidopyrimidine and a p-toluidine dimer of cyclodiazadiphosphetidine resulted in the formation of a new ligand, 2,2,4,4-tetrachloro-1,3-di-[p-tolyl]-2,4-di-[N-(pyrimidin-2-yl) benzenesulfonamide]-1,3,2,4-diazadiphosphetidine, (H2L). We investigated the chemical behavior of the newly prepared ligand was investigated by treating it with some chosen metal ions at a stoichiometric ratio of 1:2 (L:M), where M = Fe(III), Fe(II), Cu(II), Zn(II), Cd(II), and Ag(I), to provide colored complexes with accepted yields. Then, we characterized the ligand and related complexes using spectroscopic and analytical techniques. Investigations revealed that the geometrical structure of the complexes was octahedral, except for the silver complex was tetrahedral. From the spectral analyses, …

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Enhanced Adsorption Of Anionic Dyes Using Sr-Doped Zno Nanoparticles: Nonlinear Kinetics And Isotherm Studies, Mostafa H. Mohamed, Taha M. Elmorsi, H. M. Abdelbary Jan 2023

Enhanced Adsorption Of Anionic Dyes Using Sr-Doped Zno Nanoparticles: Nonlinear Kinetics And Isotherm Studies, Mostafa H. Mohamed, Taha M. Elmorsi, H. M. Abdelbary

Al-Azhar Bulletin of Science

Using a co-precipitation process, sr-doped ZnO was prepared and demonstrated to be effective in the removal of anionic congo red dye, since its surface positive charge was increased to 17.3 mV. To investigate the surface morphology and physicochemical characteristics of Sr-doped ZnO, FTIR spectroscopy, scanning electron microscopy (SEM), elemental analysis, and point of zero charges (pHPZC) were employed. We conducted batch adsorption experiments to investigate the effects of contact time (180 minutes), pH (3.5–11), adsorbent dosage (0.5–3.0 g L−1), and temperature (288–328 K). The kinetic study was modeled using several equations, including pseudo-firstorder (PFO), pseudo-second-order (PSO), Elovich, and intra-particle diffusion …

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Dr. Lawrence J. Berliner, Anit Tyagi May 2022

Dr. Lawrence J. Berliner, Anit Tyagi

DU Undergraduate Research Journal Archive

An interview with Dr. Lawrence J. Berliner.

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Strategic Consideration And Recommendation On Development Of Chemistry In China, Yanlin Cheng, Shuxian Wu, Qing Dai, Chunying Chen, Yuliang Zhao Mar 2022

Strategic Consideration And Recommendation On Development Of Chemistry In China, Yanlin Cheng, Shuxian Wu, Qing Dai, Chunying Chen, Yuliang Zhao

Bulletin of Chinese Academy of Sciences (Chinese Version)

Chemistry, as a central science linking all the other sciences, has played an influential role in promoting the development of the whole scientific and technological field and the prosperity of economy and society. Developed countries strongly support the development of chemistry and effectively promote the level of chemical research and chemical industry. Since the founding of the People's Republic of China, chemical research has been supported among the field of natural sciences, and its current level is at the forefront of the world. However, there are still problems in the field of chemistry research in China, such as insufficient major …

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Correlation Effects On Intramolecular C-H...Oh And O-H...O Hydrogen Bond Interactions In Azelaic Acid: An Ab Initio Study, Sabina Kalata, Alina Huang, Ruben Parra Aug 2021

Correlation Effects On Intramolecular C-H...Oh And O-H...O Hydrogen Bond Interactions In Azelaic Acid: An Ab Initio Study, Sabina Kalata, Alina Huang, Ruben Parra

DePaul Discoveries

Electron correlation effects on both conventional, O-H…O, and nonconventional, C-H…O, intramolecular hydrogen bonds present in a selected azelaic acid folded conformation were evaluated ab initio using HF and MP2 methodologies. The relative strength of the hydrogen bonds was examined through different indicators derived from geometry, vibrational frequencies, and electron density along the hydrogen bond path. The HF method results in weaker O-H…O and C-H…O hydrogen bonds when compared with the corresponding results using the MP2 method. Additionally, the stability of the folded azelaic conformation is found to depend on the level of theory used. Accordingly, the zero-point corrected energies of …

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Visualization Without Vision – How Blind And Visually Impaired Students And Researchers Engage With Molecular Structures, Croix J. Laconsay, Henry B. Wedler, Dean J. Tantillo Jul 2020

Visualization Without Vision – How Blind And Visually Impaired Students And Researchers Engage With Molecular Structures, Croix J. Laconsay, Henry B. Wedler, Dean J. Tantillo

Journal of Science Education for Students with Disabilities

This article examines the tools and techniques currently available that enable blind and visually impaired (BVI) individuals to visualize three-dimensional objects used in learning chemistry concepts. How BVI individuals engage with and visualize molecular structure is discussed and recent tactile (or haptic) and auditory methods for visualization of various chemistry concepts are summarized. Remaining challenges for chemistry education researchers are described with the aim of highlighting the potential value of educational research in further enabling BVI students to pursue careers in science, technology, engineering, and mathematics (STEM) fields.

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New Innovation In The Flipped Chemistry Classroom Jan 2020

New Innovation In The Flipped Chemistry Classroom

The Graduate Review

No abstract provided.

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Paradigms For Creating Activities That Integrate Mathematics And Science Topics, Janet Bowers, Kathy Williams, Antoni Luque, Devon Quick, Mary Beisiegel, Jody Sorensen, Joan Kunz, Diane Smith, Lori Kayes Jan 2020

Paradigms For Creating Activities That Integrate Mathematics And Science Topics, Janet Bowers, Kathy Williams, Antoni Luque, Devon Quick, Mary Beisiegel, Jody Sorensen, Joan Kunz, Diane Smith, Lori Kayes

Journal of Mathematics and Science: Collaborative Explorations

Research has shown that undergraduate students benefit from seeing examples of mathematics applied to real-world situations. This article describes three different paradigms for how math and discipline partner faculty worked together to create mathematical activities that illustrate applications of the topics being studied in precalculus and calculus. All three examples are discussed within the framework of PDSA cycles to describe the process by which the teams collaborated to plan, enact, study, and refine their lessons. Findings discuss both the difficulties of creating integrated activities (differences in terms and definitions between math and science faculty, different foregrounding of math versus science …

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Periodic Table Of Elements, Mendeleev's Periodic Table: History, Achievements And Problems, Boris Oksengendler, Kamil Mukimov, Renat Letfullin, Nigora Turaeva, Gulmurza Abdurakhmanov, Shavkat Yuldashev Jun 2019

Periodic Table Of Elements, Mendeleev's Periodic Table: History, Achievements And Problems, Boris Oksengendler, Kamil Mukimov, Renat Letfullin, Nigora Turaeva, Gulmurza Abdurakhmanov, Shavkat Yuldashev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

This paper, devoted to the yubilee of Mendeleev's table, deals with a set of historical and physico-chemical problems related it. Basing on the evolutional approach to the development of the concept of “elements and structure” and up to the appearance of the notion “complexity” we discuss the applicability of Mendeleev's table to the understanding of modern aspects of science such as “nano”, “fractals”, “synergetics” and “hirality”. The problems which are open for further research are revealed and the particular importance of their development for the condensed matter science of living and nonliving matter is pointed out.

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Chemical Composition And Suitability Of Some Turkish Thermal Muds As Peloids, Muazzez Çeli̇k Karakaya, Necati̇ Karakaya Jan 2018

Chemical Composition And Suitability Of Some Turkish Thermal Muds As Peloids, Muazzez Çeli̇k Karakaya, Necati̇ Karakaya

Turkish Journal of Earth Sciences

Thermal muds have been used in many spas for the treatment of different diseases as well as to clean and beautify the skin and in different forms such as mud baths, masks, and cataplasms. Mineralogical and chemical compositions and the possible toxicity of the peloids were investigated and compared with some limits to determine whether they have any health benefits and potential applications for pelotherapeutic treatments. The studied peloid samples were collected from 19 spas in different parts of Turkey and they were classified as neutral to slightly alkaline, with a high electrical conductivity value that had a high chlorine …

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Hydrogeology Of Salt Karst Under Different Cap Soils And Climates (Persian Gulf And Zagros Mts., Iran), Jiri Bruthans, Jiri Kamas, Michal Filippi, Mohammad Zare, Alan L. Mayo Jun 2017

Hydrogeology Of Salt Karst Under Different Cap Soils And Climates (Persian Gulf And Zagros Mts., Iran), Jiri Bruthans, Jiri Kamas, Michal Filippi, Mohammad Zare, Alan L. Mayo

International Journal of Speleology

Southern Iran hosts abundant salt karst phenomena in numerous salt diapirs. This paper provides a new insight into the relationships among climate, cap soil and salt karst hydrogeology. Cave systems were documented and mapped. Soil, drip, stream, and flood waters from different environments were studied at several diapirs. It was revealed that the soil water chemistry depends on both the climate and cap soil thickness. In semi-arid climates, a thick cap soil forms (>3 m) and water has very low TDS values (0.15 g/l). In arid climates, a shallow cap soil forms, and soil water is gypsum-saturated with low …

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The Chemistry Of The Flint Water Crisis, Ernest M. Oleksy Dec 2016

The Chemistry Of The Flint Water Crisis, Ernest M. Oleksy

The Downtown Review

Politics and science do not always go hand-in-hand. Nowhere was this more clear than in the Flint Water Crisis. Negligence towards growing levels of lead poisoning in drinking water led to incredibly deleterious effects on Flint's citizens. The chemistry of equilibrium and the shortcomings of local leaders led to Flint's water becoming a crisis.

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Serendipitous Discovery Of A New Method For The Catalytic Synthesis Of Indole-Fused Benzazepanes, Edward Gluzman, Paul A. Vadola Jul 2016

Serendipitous Discovery Of A New Method For The Catalytic Synthesis Of Indole-Fused Benzazepanes, Edward Gluzman, Paul A. Vadola

DePaul Discoveries

We report here on our investigations into the application of 1,5-hydride transfer cyclization mechanisms to the synthesis of 2,3-disubstituted benzofurans and indoles. We found that PtI4 in MeCN at 120 ºC was indeed capable of activating the alkyne, however, the expected 2,3-disubstituted indole product was not observed. Instead we isolated an indolyl-3-benzazepane via an unexpected intramolecular Steven’s rearrangement/ring expansion. While this transformation has been previously reported our method may prove to have increased substrate scope and more practical reaction conditions. Further studies are underway to optimize the reaction conditions and to fully explore the scope and mechanism of the …

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Ambiguity In Speaking Chemistry And Other Stem Content: Educational Implications, Mick D. Isaacson, Michelle Michaels Sep 2015

Ambiguity In Speaking Chemistry And Other Stem Content: Educational Implications, Mick D. Isaacson, Michelle Michaels

Journal of Science Education for Students with Disabilities

Ambiguity in speech is a possible barrier to the acquisition of knowledge for students who have print disabilities (such as blindness, visual impairments, and some specific learning disabilities) and rely on auditory input for learning. Chemistry appears to have considerable potential for being spoken ambiguously and may be a barrier to accessing knowledge and to learning. Educators in chemistry may be unaware of, or have limited awareness of, potential ambiguity in speaking chemistry and may speak chemistry ambiguously to their students. One purpose of this paper is to increase awareness of potential ambiguity in speaking chemistry and other STEM fields …

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Investigation Of Irrigation Water Quality Of Surface And Groundwater In The Kütahya Plain, Turkey, Berihu Abadi Berhe, Mehmet Çeli̇k, Uğur Erdem Dokuz Jun 2015

Investigation Of Irrigation Water Quality Of Surface And Groundwater In The Kütahya Plain, Turkey, Berihu Abadi Berhe, Mehmet Çeli̇k, Uğur Erdem Dokuz

Bulletin of the Mineral Research and Exploration

The Kütahya plain is one of the plains in Kütahya/Turkey, where drinking, agricultural and industrial water supplies are highly dependent on groundwater resources. The local population largely depends on water from alluvial shallow aquifer waters and some on the Felent and Porsuk rivers. Appraisal of surface and groundwater quality is extremely important to make sure the sustainable use of it for drinking, agricultural, and industrial purposes. The chemical quality of surface and groundwater of Kütahya plain has been studied in detail in order to have better understanding of potential water quality. A total of 21 groundwater samples and 6 surface …

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Learning Chemistry Through Experimentation, Brent Kamba `, Dr. Jennifer Nielson Apr 2015

Learning Chemistry Through Experimentation, Brent Kamba `, Dr. Jennifer Nielson

Journal of Undergraduate Research

There is a great need for students to learn scientific skills in Uganda. Very few students pass the national chemistry exams (about 40%) and even fewer go on to study science fields in higher education. The teaching methods in Uganda are a little bit old fashion where students often just learn facts and practise rote memorization. Rarely do they develop the critical and analytical skills to help them succeed in science jobs. Teachers also express that the curriculum is very theoretical, and not experimental.

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Fall 2014 Sep 2014

Fall 2014

Scientia

CSH progress notes; Alumna entrepreneur finds success at the intersection of chemistry and law; Lions, lycopods and laboratories: CSH students thrive in summer internships; Fielding a team for a mission to Mars; Professor Craig Klugman on the medical humanities; Lab Notes

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Chemistry Division, Marie Fraties-Block Jan 2012

Chemistry Division, Marie Fraties-Block

Sci-Tech News

No abstract provided.

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Beyond The Chemistry Web, Robert A. Buchanan Dec 2011

Beyond The Chemistry Web, Robert A. Buchanan

Sci-Tech News

No abstract provided.

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Beyond The Chemistry Web, Robert A. Buchanan Apr 2011

Beyond The Chemistry Web, Robert A. Buchanan

Sci-Tech News

An abstract is not essential for a column.

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An Activity Promoting The Practice Of Quantitative Literacy For Pre– And In–Service Teachers Of Mathematics And Science, Timothy L. Sorey, Teri Willard, Duane Sholz Dec 2009

An Activity Promoting The Practice Of Quantitative Literacy For Pre– And In–Service Teachers Of Mathematics And Science, Timothy L. Sorey, Teri Willard, Duane Sholz

Numeracy

The purpose of this article is to describe a hands-on, laboratory activity that provided pre-service teachers in mathematics and science methods courses, and also some in-service mathematics teachers, with the opportunity to exercise quantitative literacy (QL) skills. The focus of the activity is electrical resistance, more particularly the resistance (in ohms) that is painted on small resistors by the use of color-coded bands, one of which is a band for % error. The activity consists of four parts. In the first, student teams familiarize themselves with the code, measure the ohmage of resistors for which the codes are visible, and …

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Hydromination Of Alkynes, Enynes, And Dienes Using Titanium Catalysts, Taryn Palluccio Jan 2007

Hydromination Of Alkynes, Enynes, And Dienes Using Titanium Catalysts, Taryn Palluccio

Undergraduate Review

No abstract provided.

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Surge Of Green: A Sustainable Approach To Conductive Polymers, Bethany Masten Jan 2007

Surge Of Green: A Sustainable Approach To Conductive Polymers, Bethany Masten

Undergraduate Review

No abstract provided.

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