Previous educational articles on microfluidic technology mainly focused on continuous microfluidics, so we set up an undergraduate laboratory experiment to introduce droplet microfluidics to students. Students can understand the concept of microfluidic channels and the principles of droplet microfluidics, prepare polydimethylsiloxane (PDMS)…

Electrocatalytic hydrogenation of acetol (IUPAC: 1-hydroxy-2-propanone), a species formed upon thermal liquefaction of biomass, can be achieved using inexpensive objects: filter paper, coins, batteries, salts, and water. This simple example demonstrates that "green" chemical transformations can be achieved with familiar items and helps…

A series of hands-on experiments including the synthesis and application of flexible, conductive silver-nanopaste were designed to gain knowledge of conductive soft nanomaterial and the synthesis and the application of silver nanopaste (Ag nanopaste). The aim of this laboratory experiment is to provide undergraduate/graduate students an…

Interfacial solar vapor generation has recently drawn much attention because of its high solar-to-vapor generation efficiency. Here we introduce the basic experimental procedures and analysis for undergraduates to perform such an experiment to catch up with the cutting-edge research wave. Interfacial solar vapor generation employs an interfacial…

Fast, reliable, well-resolved latent fingerprints can be planted by applying a thin coating of a 50:50 mixture of hand lotion and food-grade protein powder. Fingerprints can be revealed with iodine fuming or ninhydrin staining. This low-cost alternative to commercial latent print pads can be used in a variety of classroom or public settings where…

A simple bioassay was designed for the detection of adenosine, a human metabolite involved in several physiological processes, on the basis of the functionalization of gold nanoparticles with DNA oligonucleotides selectively binding adenosine. The test was possible thanks to the selective and sensitive binding of adenosine by two DNA…

Electrochemical analysis is an important skill to teach in chemistry curricula because it is a critical tool in current high-impact chemical research. Electrochemistry enables researchers to analyze a variety of systems extending from molecules to materials that encompass research themes ranging from clean energy to substrate activation in…

Reviews the Hafele-Keating experiment on relativistic changes in eastward and westward moving cesium atomic clocks. Recommends the use of the Sagnac effect to remove the east-west time asymmetry and of the general-relativistic effect to elucidate the clock-rate changes. (CC)

In this simple experiment for an undergraduate laboratory a laser beam is passed through the mixing zone of two liquids with different refractive indices. The spatial variation of the refractive index, at different times during the mixing, can be determined from the observed deflection of the beam. (Author)

Presents a procedure by which cytokinins are used to induce a population of dividing and differentiating cells on the cut surface of the roots of an intact plant. Includes the method used, results, and suggestions for a variety of variables that may be tested. (RT)

Discusses procedures of using the selective absorption properties of manganese dioxide to prepare a short-lived source from the cerium-144/praseodymium-144 system. (CC)

A simple experiment is proposed that can provide the student with some insight into the chemical properties of solids. It also demonstrates the relationship between the Gibbs free energy of formation of an ionic solid and the emf of an electrochemical cell. (DF)

This procedure, using polystyrene spheres of specified diameter, renders the Millikan oil drop experiment more accurate than the conventional procedure of the polystyrene spheres, eliminates size estimation error, and removes the guesswork involved in assigning proper index integers to the observed charges. (MLH)