Guangdong Medical University, formerly the Zhanjiang Branch of Sun Yat-sen Medical College founded in 1958, was upgraded to a five-year medical undergraduate institution and renamed Zhanjiang Medical College in 1964, renamed Guangdong Medical College in 1992, and renamed Guangdong Medical University in 2016. It was rated a national advanced unit in culture and education in 1960; two research achievements won National Science Conference awards in 1978; it gained master's-degree authorization in 1986 as a key construction university of Guangdong Province; won first prize in the Guangdong education evaluation in 1991; received "Excellent" in the Ministry of Education undergraduate teaching evaluation in 2005; established a postdoctoral research station in 2008; was listed by Guangdong in 2009 as a project construction unit for new doctoral-degree authorization within national quotas; established a Ministry of Education sci-tech novelty search workstation in 2012; and was approved as a doctoral-degree granting institution in 2013. Clinical medicine entered the ESI global top 1% in May 2015, the university entered the ESI global top 1% in January 2016, and pharmacology and toxicology entered the ESI global top 1% in July 2020. 

The customer purchased our WKT-A3 moisture analyzer. The WKT-A3 "Vision" Karl Fischer trace moisture analyzer uses the Karl Fischer coulometric principle to rapidly determine trace moisture down to 1 ppm, measuring trace moisture in solids, liquids and powders within 1 minute. The instrument has a built-in printer, stores 200 data sets, and supports real-time query and printing, with printed data covering all operations, formulas, calculations and reports required by numerous national standards! Its 5.7-inch (320*240 mm) LCD, friendly interface, keypad design, fault self-diagnosis, automatic interference deduction, reagent life reminder and other classic features make it simple and fast. The WKT-A3 complies with multiple national and international moisture measurement standards, with eight built-in moisture calculation formulas and 6 measurement methods for various industries, widely used in chemical, petroleum, pharmaceutical, electric power, food, scientific research and testing industries.

The customer purchased our instrument mainly for teaching, so during installation and commissioning we focused more on explaining the instrument's principles to the students, plus basic operation and maintenance. The customer mainly tests daily chemical products such as shampoo, shower gel and soap. Since some samples cannot dissolve completely in methanol, they cannot be tested directly (a Karl Fischer oven solution is required), but samples such as body oils can be tested with our instrument. We first completed the installation, then verified the instrument with deionized water: we injected 2 µL of deionized water into the reaction vessel and, after the reaction finished, read the result of 1952 µg, within range. We then tested the customer's sample; because its moisture was high, we took only 50 mg. After injecting the sample and entering the 50 mg mass once the reaction finished, the result was 89.2%—close to the customer's theoretical value and within range. High-moisture samples like this actually suit our volumetric moisture analyzer better, but because the customer also has samples with moisture of only a few hundred ppm, they chose our volumetric moisture analyzer.