By building a schlieren optical system, the visualization of a 40 KHz sound wave is realized. By using the schlieren system, the demonstration of acoustic reflection, interference and diffraction can be easily realized. At the same time, the visual acoustic field provides another simple way for the measurement of sound velocity. In this paper, the…

A common procedure when conducting physics experiments is to repeat a measurement several times to calculate the mean and standard deviation. That might be the only instruction we give to students as a means to minimize random errors. However, that technique does not guarantee that the answer will be correct. It might give the same wrong answer…

We have investigated the motion of water flow through glass tubes of different shapes by calculating the value of the Reynolds number denoted as Re. We know that at a given flow rate the value of Re determines the type of flow being classified as laminar, transitional or tubulent. The dependence of Re in different configurations of glass tubes as…

The goal of this laboratory exercise is to give upper-level undergraduate students an introduction to sterile technique in mammalian cell culture and metabolism. The experiment can be completed within a 3-h lab period and can be performed either in conjunction with other biochemistry/metabolism experiments or used as a stand-alone experiment. In…

Kundt's tube is a popular experiment commonly used in schools, in which standing sound waves are made visible inside a glass tube. A fine powder is stirred up in areas of high sound particle velocities, so that one can measure the wavelength of the sound waves by examining the patterns created. In this way, the 'invisible' can be made visible.…

Chemical screening libraries often feature natural product extracts (NPEs) due to the intriguing biological activities they possess and the structural diversity found in their individual components. A research project originally designed to create an extract library of every specimen in the University of Rhode Island (URI) Heber W. Youngken Jr.…

Understanding the abstract principles of statistical experimental design can challenge undergraduate students, especially when learned in a lecture setting. This article presents a concrete and easily replicated example of experimental design principles in action through a hands-on learning activity for students enrolled in an experimental design…

X-ray crystallography provides structural information of molecules at the atomic level, being a central technique at the forefront of science and technology. However, crystallography teaching is not usually implemented in biochemistry lab classes due to its complex execution by nonexpert users. Here, we report the basic step-by-step workflow…

This laboratory experiment, designed for undergraduate nonmajors or advanced high school students, attempts to demystify the technique of spectrophotometry by utilizing a hands-on, real-world approach. Modification of the reaction for the formation of Fe[(bpy)[subscript 3]][subscript 2+] allows students to interact with vitamin C, a compound with…

Picture boards as a visual support aid for in-lab demonstrator briefings were deployed for a single experiment in both the first and second year undergraduate practical classes. The boards are easy to create and provide an alternative, more accessible and 'presentation friendly' perspective of the laboratory manual associated with an experiment.…

Flavonoids have been studied extensively for their antioxidant properties. Specifically, the flavonoids in tea, such as catechin and epigallocatechin gallate, have been shown to have positive health effects. These compounds are also oxidizable, so the concentrations of these compounds in a given kind of tea can be determined using cyclic…

This innovative comprehensive experiment is a compulsory course for third-year undergraduate students in the eight-year training program leading to a Doctor of Medicine degree or Doctor of Philosophy degree at Peking University Health Science Center (PKUHSC). There is a critical educational need to prepare these students for the increasing…

The importance of understanding factors that contribute to surface wettability is highlighted in this new organic chemistry laboratory experiment, which aims to introduce the application of organic chemistry at the interface of polymer chemistry and material science. Polydimethylsiloxane (PDMS), a hydrophobic silicon-based rubber, is polymerized…

We propose to reconsider the well-known experiment about the interference of white light from a thin soap film by adopting as an illuminating source the RGB triad produced by a LED projector. The interference pattern shows up in a particularly fascinating way and it contains direct, essential information about both the wave nature of light and of…

Differential equations are widely used tools for modelling the world around us, making a course in differential equations a natural place for students to connect concrete mathematical applications to abstract concepts. Since students grasp the concepts better by applying them, introducing differential equations through modelling becomes essential.…