- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Introducing Manganese-Doped Lead Halide Perovskite Quantum Dots: A Simple Synthesis Illustrating Optoelectronic Properties of Semiconductors
摘要： Quantum dots (QDs) are considered useful for demonstrating quantum phenomena in undergraduate laboratories due to their monodisperse size and excellent optical properties. Although doping has an increasingly important role in QD fabrication in the semiconductor field, it has rarely been discussed in the context of the undergraduate laboratory. In this work, a simple synthesis and characterization method for Mn-doped CsPbCl3 QDs for an upper-level undergraduate inorganic chemistry laboratory is reported. The Mn-doped CsPbCl3 system benefits from a simplified synthesis and straightforward characterization. This experiment introduces QD research to students and offers opportunities for instructors to discuss many important concepts in inorganic chemistry, such as energy band theory, particle-in-a-box model, electron paramagnetic resonance, ligand field theory, and nanochemistry.
关键词： Inorganic Chemistry,Crystal Field/Ligand Field Theory,EPR/ESR Spectroscopy,Upper-Division Undergraduate,Hands-On Learning/Manipulatives,Laboratory Instruction,Nanotechnology
更新于2025-11-20 15:33:11
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Raman spectroscopy coupled with ambient ionization mass spectrometry: A forensic laboratory investigation into rapid and simple dual instrumental analysis techniques
摘要： We present a laboratory experiment, developed around a pair of instrumental analysis techniques, Raman spectroscopy and ambient ionization mass spectrometry (MS), conducted by senior chemistry undergraduate students for bulk analysis of over-the-counter drugs using benchtop versions of the two instruments, as well as trace analysis of illicit drugs utilizing the corresponding portable instruments. The identification and confirmation of seized drugs is a routine operation in forensic laboratories that can be simplified using these two instrumental techniques in tandem. Bulk samples are readily analyzed using conventional Raman spectroscopy followed by paper cone spray ionization (PCSI) MS, while trace analysis is allowed by a simple single-substrate dual-analyzer method using surface enhanced Raman spectroscopy (SERS) from paper followed by paper spray ionization (PSI) MS. The introduction of these novel strategies to the students exposed them to potential career paths in forensic science by means of a hands-on experience that provided fundamental knowledge about this set of analytical methods, including intercomparisons of their performance, as well as practical issues like costs, regulations and databases. The use of portable instrumentation represents an additional learning experience for the students, considering that it is cutting-edge technology that is just now being transferred from academic to industrial labs and that it allows a valuable discussion of the advantages and disadvantages of bringing the laboratory to the field.
关键词： Mass spectrometry,Hands-on learning,Forensic analysis,Drugs of abuse,Paper cone spray ionization,Paper spray ionization,Paper surface enhanced Raman spectroscopy,Raman spectroscopy,Ambient ionization,Laboratory instruction
更新于2025-09-23 15:21:01
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Simple Acid Vapor Method for Production of HCl and DCl Gas for IR Spectroscopy
摘要： We report here a method that utilizes the vapor pressure of HCl(g) above a concentrated HCl(aq) solution as an extremely simple and safe method to produce small amounts of HCl vapor in an IR gas cell. This vapor pressure approach can also be used to produce DCl(g) by introducing a few drops of concentrated DCl(aq) into the gas cell.
关键词： Physical Chemistry,Laboratory Instruction,IR Spectroscopy,Upper-Division Undergraduate,Hands-On Learning/Manipulatives
更新于2025-09-23 15:21:01
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Identification of Proteins Using Four Methods of Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry
摘要： An upper-division undergraduate- or graduate-level laboratory experiment, challenging students to identify bovine serum albumin, equine myoglobin, bovine calmodulin, and bovine cytochrome c, uses four methods of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS): linear positive, in-source decay, peptide mass fingerprint, and postsource decay. Individual hands-on experience with each method is provided in a three week experiment. The importance of sequencing proteins/peptides when identifying proteomic targets using MALDI-TOF MS is emphasized.
关键词： Mass Spectrometry,Hands-On Learning/Manipulatives,Upper-Division Undergraduate,Laboratory Instruction,Graduate Education/Research,Bioanalytical Chemistry,Biotechnology,Analytical Chemistry,Biochemistry
更新于2025-09-19 17:13:59
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Analytical Methods for Monitoring the Degradation of Plasmonic Nanoparticles in Solution: An Instrumental Analysis Laboratory Exercise
摘要： Nanoparticles are an increasingly important in chemistry research, but currently there are few opportunities for chemistry students to work with nanoparticles in undergraduate analytical courses. In this exercise, designed for an analytical or instrumental analysis lab course, students have the opportunity to work with solutions of silver nanoparticles and analyze them with two instrumental techniques. UV?vis spectrophotometry is utilized to monitor the optical behavior of silver nanoparticles over the course of the experiment. ICP-OES analysis determines the concentration of total silver species present in solution based on storage conditions. This exercise also introduces students to the concept of localized surface plasmon resonance and its role in producing the vivid colors often associated with plasmonic nanoparticles embedded in stained glass.
关键词： Upper-Division Undergraduate,Instrumental Methods,Collaborative/Cooperative Learning,Laboratory Instruction,Analytical Chemistry,Nanotechnology,Problem Solving/Decision Making
更新于2025-09-19 17:13:59
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Production and Evaluation of a Realistic Immersive Virtual Reality Organic Chemistry Laboratory Experience: Infrared Spectroscopy
摘要： Using virtual reality (VR) in educational settings is becoming increasingly popular. The feasibility of replacing an instrumentation-based organic chemistry lab with a VR experience has been evaluated. A VR laboratory experience was designed to teach students how to use an infrared spectrometer and elucidate an unknown structure from the resulting infrared spectrum. The resulting first-person VR experience is immersive and realistic, with a teaching assistant guiding the user along the steps required to complete the experiment, including feedback as needed. The VR experience was developed in WondaVR with selections made using gaze navigation. The resulting product was tested with a group of students, and the outcomes for short- and long-term recall were compared with a group of students that did the same experiment in a traditional lab. Results indicate that there are no significant differences in learning outcomes between the two groups, which indicates the possibility of using this tool to offer this organic chemistry lab experiment via distance education. Students that tried the VR experience reported a high degree of satisfaction with the product and no significant usability barriers. These VR experiences could be useful for students who are unable to be present in lab due to disabilities, attendance challenges such as pregnancy, or safety concerns.
关键词： Second-Year Undergraduate,Laboratory Instruction,Multimedia-Based Learning,Computer-Based Learning,Distance Learning/Self Instruction,Instrumental Methods,Student-Centered Learning,Organic Chemistry
更新于2025-09-12 10:27:22
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A Simple Synthetic Approach To Prepare Silver Elongated Nanostructures: From Nanorods to Nanowires
摘要： A procedure for one-pot preparation and characterization of silver 1D nanostructures is described. The main advantages of this synthetic approach are the simplicity and reproducibility, where the size of the final product can be controlled just by changing the reaction time. This experiment is designed as a laboratory introduction to colloidal chemistry for undergraduate and graduate students; they can appreciate the role of the different reagents in a relatively complex reaction and understand the relation between the morphology of a metal at the nanoscale and some macroscopic properties, such as its visible absorption spectrum (i.e., color).
关键词： Nanotechnology,Synthesis,Second-Year Undergraduate,UV?Vis Spectroscopy,Physical Chemistry,Laboratory Instruction,Hands-On Learning/Manipulatives,First-Year Undergraduate/General,Metals,Colloids
更新于2025-09-04 15:30:14
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Process Analytical Technology for Online Monitoring of Organic Reactions by Mass Spectrometry and UV–Vis Spectroscopy
摘要： Process analytical technologies (PATs) are used in the pharmaceutical and other industries to monitor chemical processes in real-time with analytical instrumentation. Each PAT analyzer brings its own advantages and disadvantages to the process, and multiplexing PAT analyzers can be advantageous as they can provide confirmatory measurements and increase the overall confidence of the analysis. In a pedagogical setting, online reaction monitoring enables the instructor to explain the fundamentals of instrumental techniques while highlighting pertinent real-world applications. Here we present a teaching laboratory exercise in which students monitor an amide bond formation reaction by flow UV?vis spectroscopy and by mass spectrometric analysis. The coupling of these two specific instruments allows students to investigate two instruments in one laboratory exercise, to explore the fundamentals behind each, and to contemplate the advantages and disadvantages of these instrumental methods. The coupling of the two instruments was aided by 3D printing which allowed students to explore how rapid prototyping can enable the development of innovative procedures.
关键词： Organic Chemistry,Mass Spectrometry,UV?Vis Spectroscopy,Laboratory Instruction,Instrumental Methods,Hands-On Learning/Manipulatives,Upper-Division Undergraduate,Analytical Chemistry,Reactions
更新于2025-09-04 15:30:14