Physical Sciences and Mathematics Commons^™

What Can General Chemistry Students Learn From External Representations Of Acid- Base Titrations?, Nicole Baldwin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Laboratory activities are a prevalent and essential part of chemistry learning because of their potential to help students develop problem solving abilities, visualize chemistry concepts learned in lecture, and gain practical skills. However, learning in the laboratory environment is not without its challenges. For example, cookbook-style chemistry laboratories can promote superficial learning, and cognitive overload can result from the study of new concepts and the use of new procedures in this environment. Multiple pedagogies and supports have been developed to address challenges such as these. The current research focuses upon external representations that are commonly used to support learning in …

What Do General And Organic Chemistry Students Consider When Making Decisions About Acids And Bases? A Phenomenographic Study, Sarah Wood

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Chemistry students often struggle in organic chemistry courses. In fact, these courses are viewed by some as “weed-out” classes. There are many fundamental concepts covered in general chemistry that contribute to students’ ability to succeed in organic chemistry. One of those fundamental topics, and the focus of this study, is the topic of acids and bases. Acid–base topics are featured in both general and organic chemistry courses, and the interests of this study lie not only within the realm of organic chemistry but also general chemistry.

The purpose of this study was to determine both undergraduate general and organic chemistry …

Using Two Simulation Tools To Teach Concepts In Introductory Astronomy: A Design-Based Research Approach, Pamela A. Maher

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Technology in college classrooms has gone from being an enhancement to the learning experience to being something expected by both instructors and students. This design-based research investigation takes technology one step further, putting the tools used to teach directly in the hands of students. The study examined the affordances and constraints of two simulation tools for use in introductory astronomy courses. The variety of experiences participants had using two tools; a virtual reality headset and fulldome immersive planetarium simulation, to manipulate a lunar surface flyby were identified using a multi-method research approach with N = 67 participants. Participants were recruited …

Structural Behavior Of Nbsexte2-X Superconductors Under High Pressure, Vahe Mkrtchyan

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Niobium chalcogenide compounds have recently gained a great deal of interest due to the fact that a superconducting phase coexists with the charge density wave state (CDW), as well as their potential for numerous applications. Two superconducting compositions, NbSexTe2-x (x=2, 1.5) were prepared by solid state route using high purity Nb, Se, and Te powders. Powder X-ray diffraction patterns collected at ambient conditions for NbSe2 and NbSe1.5Te0.5 showed a single phase with hexagonal crystal structure, with space group P63mmc. High-pressure X-ray diffraction measurements were performed at the Advanced Photon Source at Argonne National Laboratory to investigate structural stability up to …

Development And Testing Of An Assessment To Measure Spatial Thinking About Enhanced Greenhouse Effect, Heather Jean Skaza

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Americans, in general, do not behave in environmentally sustainable ways. We drive cars and fly in planes that emit planet-warming carbon. We purchase food in nearly indestructible packaging that is not recycled or repurposed. We do not consider the environmental impact of the “stuff” stuffed into our grocery and department stores, most of which is made of materials that had to be dug out of the ground, leaving rivers and skies full of pollution in its place. Citizens have a responsibility to understand complex global and local environmental problems. A person’s ability to think about the way that an environmental …

Estimation Of The Tax Rates Based On Vehicle Miles Traveled Using Stochastic Models, Pratik Verma

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In this thesis, we shall study the alternative revenue collection system which is based on the vehicle miles traveled (VMT). In various studies, it has been found that the existing revenue collection system based on gas/fuel tax is not an appropriate option in the longer run. The main reasons include no effective tax process for vehicles based on alternative fuel vehicle, no effective changes in tax due to economical inflation, and more highway expenditure than generated revenue. Our main objective is to estimate the VMT tax rates that should be charged in order to generate same amount of revenue generated …

What Can Biochemistry Students Learn About Protein Translation? Using Variation Theory To Explore The Space Of Learning Created By Some Common External Representations, Thomas J. Bussey

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Biochemistry education relies heavily on students' ability to visualize abstract cellular and molecular processes, mechanisms, and components. As such, biochemistry educators often turn to external representations to provide tangible, working models from which students' internal representations (mental models) can be constructed, evaluated, and revised. However, prior research has shown that, while potentially beneficial, external representations can also lead to alternative student conceptions.

Considering the breadth of biochemical phenomena, protein translation has been identified as an essential biochemical process and can subsequently be considered a fundamental concept for biochemistry students to learn. External representations of translation range from static diagrams to …

Assessing The Effect Of Simulation Models On Systems Learning In An Introductory Environmental Science Course, Heather J. Skaza

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While there is plenty of anecdotal evidence within the systems dynamics community supporting the use of systems simulations in the classroom to improve student understanding, there is little published, controlled, experimental research. This paper describes the results of a paired experiment testing the effect of using system dynamics simulations to increase systems understanding in an introductory environmental science course. We believed that the students using the systems simulations would demonstrate a greater systemic understanding of environmental issues than those who did not.

We conducted an experiment during the fall semester of 2009, with 304 students enrolled in four sections of …

Measuring The Environmental Attitudes Of Children In Grade 4: A Study In Clark County, Amir Khawaja

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The purpose of this study was to examine whether there is an increased positive effect on children's attitude when they are taught about the environment in an outdoor/hands-on setting versus an indoor traditional classroom setting. The study focused on grade four students in the Clark County School District. Half of the group was comprised of students that were taught about the environment using traditional classroom learning materials while the other half consisted of students that were taught using the outdoor/hands-on approach. In order to test the results, the students were given a survey. The questionnaire created by Malkus and Musser …