TLDR: This page contains those Top Posts that would otherwise be hard to find in a chronological Blog Roll. For the latest posts, click the blog roll.
Research and the Betterment of Society
Cleaning Research Group – The CRG studies all aspects of industrial cleaning processes, cleaning solvents, detergent formulations, cleaning equipment, blend formulations, and validation techniques. We have contracted with industry and government agencies to study replacement technologies for better performance, improved worker safety, and environmental sustainability.
Product Quality Cleaning Workshops – The PQCWs are a main outlet for the research performed by the Cleaning Research Group at Sam Houston State University. To receive bottom-line-relevant training in a hands-on environment, get on the mailing list for the PQCW.
Glove Selection – Perhaps your lab is typical in selecting nitrile gloves for everything. Changes are made when one loses a finger (of a glove) in a beaker of solvent. This is not the best practice, but many will not believe me when I say that there is an “easy alternative” to the “lost-finger” selection scheme.
Contact Angle Measurement – Measurement of contact angles often provides valuable information as to the cleanliness of a surface as well as the ease of wetting of a surface with a coating such as paint or other organic species. Previous methods based on use of a sessile drop were subject to considerable operator error. In order to minimize such errors, the computer-based analysis of drop shape has been developed. The use of such software which is Windows-compatible and easy to learn, is described, giving results where operator-error is minimized. The method has considerable potential for Quality Control in surface finishing.
Solvent Substitution (Part 1) (Part 2) – Part one of this article examines two cleaners including a hydrofluoroether (HFE) and a hydrofluorocarbon (HFC) currently being considered as potential replacements for flammable solvents. Cleaning efficacy, short-term and long-term materials compatibility, corrosion, drying times, flammability, environment, safety and health (ES&H) issues and accelerated aging studies are among the tests that are being conducted and that are used to screen candidate solvents. Part two, appearing in the October issue features the results, which are compared to the traditionally used isopropyl alcohol, which serves as the baseline cleaner.
Teaching and Education
You are reading my personal blog. My university page, the Cleaning Research Group page, and the Product Quality Cleaning Workshop pages are hosted at the University.
Excel Boot Camp Videos – I am creating a series of Excel tutorial videos on YouTube to help my students (and anyone else) learn Excel for scientific data analysis. To find all the tutorial posts use the Excel Boot Camp Tag.
Physical Chemistry Lecture Videos – My students captured my lectures for the 2017-2018 academic year and posted them the the Physical Chemistry at Sam Channel.
Forensic Chemistry Lecture Videos – Jessy Stone created the Forensic Chemistry at Sam Channel as an SHSU Honors Contract for the course – an activity that supplements the material for the student and enhances the skills that they take away from the course.
Personal Details
Perhaps, you have some questions like “What is Pchem?”, “Why does DW love it?”, and “Who is DW?”.
Nerd Fun
Yes, my hobby is Excel.
PChem4all - Dr. Williams' Science Blog 
Hello, I watched your course on ” Projection Operator Applied to Vibrations and Atomic Orbitals ” in youtube. It’s really great excellent your explanation. You easily explain the vibration of the water molecule through a simple addition of vectors but can we do this for polyatomic molecules like (NH3, CH4, CH4Cl,…)
Thanks for useful courses on Youtube
Hi Ahmed. YES you can do the vector cancellation method on three dimensional molecules like NH3 etc. But it is more difficult to visualize. Thank you so much for the kind words about the videos! Keep “pchemming”