A laboratory exercise for the synthesis of a sulfonated styrene-"co"-maleic anhydride polymer and its application as a stain blocker on nylon-6,10, is described. The effectiveness of the sulfonated polymer to prevent the conjugate base of an acid dye from staining the polyamide is demonstrated. This experiment is designed for…

To study the absorption of ultrasound in plexiglas we propose to use gadgets that are available to each student: an ultrasound humidifier, a liquid crystal display of a pad, a polaroid analyzer, a digital camera, a multimeter with thermocouple, and a stopwatch. These devices allow us to visualize a region in plexiglas where ultrasound is absorbed…

Oscillations and resonance are essential topics in physics that can be explored theoretically and experimentally in the classroom or teaching laboratory environments. However, one of the main challenges concerning the experimental study of resonance phenomena via forced oscillations is the control of the oscillation frequency, which demands an…

Newton's law of cooling describes an object whose temperature decreases exponentially with time. Because of its many applications, it is a frequent topic of introductory physics labs. In this article, I describe an experiment designed for the freshman year algebra-based physics course that applies this law to answering the question, "Why…

"N"-Formamides are important intermediates in the synthesis of many pharmacologically active compounds and are used as protecting groups for amines or as catalysts in different reactions. The current "N"-formylation experiment is designed as a part of an introductory organic chemistry course for undergraduate students. The…

Laboratory education is a defining feature of chemistry degree courses, with one of the fundamental aims being acquiring competency in a range of chemistry-specific practical skills, yet there are still limited reports of direct assessment of these skills. Here, we present the development, implementation, and evaluation of a station-based…

The Tesla coil is one of the most famous and popularly recognizable high voltage devices. Utilizing the fame of recognizability of the Tesla coil in a "Build Your Own" laboratory exercise is a great way to create a successful and highly interesting learning activity. Classical Tesla coils utilize a spark gap as the primary switch,…

Recently available local positioning systems (LPS) have the potential to be used for interactive physics laboratory activities and classroom demonstrations. The Pozyx LPS combines multiple sensors with position data for any object that one of the devices is attached to. Devices referred to as "tags" (Fig. 1[a]) are mobile devices that…

Aim of the present study is to analyze science teacher candidates' laboratory videos by using Many-facet Rasch model. Survey method was used in the study. The study was conducted in 2017-2018 academic year spring semester. Rasch model's surfaces are respectively: 9 juries, 13 science activities and 19 criteria. FACETS program was used for data…

This laboratory experiment describes the production and purification of plasmid DNA for undergraduate biochemistry and biotechnology courses. This experiment performed in a one-week period includes the protocols for plasmid pVAX1-LacZ production in "Escherichia coli" DH5[alpha] cells and subsequent purification of supercoiled pVAX1-LacZ.…

When student projects require an analytical step that is robust and sufficiently selective, high performance thin layer chromatography (HPTLC) is a method to be considered. However, for student laboratories not equipped for HPTLC, sample application as a sharp narrow band is a hurdle. The low eluting power of water on reversed phase plates can be…

A six-laboratory session biofilm-focused biochemistry laboratory module is described. Through just six four-hour laboratory sessions over three weeks, students first master background knowledge and fundamental experimental techniques to explore questions involving bacterial biofilms at the interface of microbiology and biochemistry and then…

This technology report outlines the design and construction of a simple Arduino-based pH sensor using universal pH paper; it can be assembled for less than $40 and is ideal for use in laboratory classrooms teaching students with visual disabilities. The device is simple to construct and suitable for adoption in school chemistry laboratories…

The study of gels and their properties is a compelling topic both technologically and scientifically, and should therefore be emphasized in chemistry and material science syllabuses. In the present laboratory experiment, we propose two experiences, aimed at introducing gelation and gel transport properties using silica gels made from sodium…

A laboratory exercise on the interaction between the herbicide pendimethalin (PM) and goat serum albumin (GSA), a carrier protein present in mammalian blood circulation, is described. Fluorescence spectroscopy was used to study the binding reaction between PM and GSA. Titration of a constant amount of the protein (GSA) with increasing ligand (PM)…