James J. Sullivan

James Joseph Sullivan of Middletown, Delaware peacefully passed away on Sunday, May 10th, 2026. He was 84 years old. Jim was born in Pasadena, California to Bill and Thelma Sullivan. He studied math, physics, engineering, and business at Santa Clara University, Brown University, and the University of Delaware, earning a Bachelors and three Masters degrees in Physics, Electrical Engineering, and Business Administration. His career at Hewlett Packard’s Avondale, Pennsylvania Division of Analytical Instruments, spanned over 30 years and focused on detectors for gas chromatographs, particularly his invention of the atomic emission detector or AED. 

Jim was a family man and deeply devoted to his wife Gail Sullivan for 60 years whom he greatly missed after her passing in 2023. Jim and Gail loved taking their three children to museums, amusement parks, the UD pool, and to Holy Family Catholic Church on Sunday as well as to the Jersey Shore with Gail’s parents. Jim’s love of nature meant neighborhood bike rides, boating on the Delaware, and hiking at Iron Hill with his children. He was a tinkerer and once built a small boat in the basement with his son which they took to Lums Pond. He volunteered at church, particularly enjoying handing out pastries with Gail at Resurrection Church after mass, and at area public schools to support his children. He spent many nights helping with homework projects and many weekends supporting his kids in scouts, sports, and musical pursuits, always ready to be the chauffeur for adventures. In his retirement, he loved to read, write creative stories, and go on trail runs, eventually joining Trail Dawgs running club and completing countless 5K’s, half marathons, and marathons. He swam at the Senior Center in Newark and ran a creative writing group there called “the Scribblers”, volunteering his time to collect creative stories of seniors and “publish” them in a booklet sent out to the members. He could be counted on to write the Sullivan Family Christmas letter each year and send photos to maintain a connection with family all over the United States.    

Jim’s work and interests often took him around the globe as he spoke about his inventions at conferences and trained others in the use of the AED. His business cards described him as the “attack physicist,” a phrase which gives a glimpse into how funny Jim was. Upon retirement, he became a contractor for HP to continue to serve in the role of tech support for the AED. His business degree allowed him to pursue other patent ideas after leaving HP and culminated in him starting his Jindai Bio business. He continued to publish papers and chair committees for the Eastern Analytical Symposium until his early 70’s. He worked in China at one point and developed a deep interest in Asian culture and languages. Due to his travels, he could be heard speaking or reading Mandarin, Japanese, German, or French. He filled his home with souvenirs from this time and maintained friendships with scientists in several countries, notably Chinese friend and colleague Xiao-Jia Cai and English scientist Jim Lovelock. Jim loved learning and engaging in discussions about anything, not just physics, and books lined his shelves on topics such as cosmology, politics, art, creative writing, religion, and how to train for long distance running. His family and his caregivers, Agnes Fudzie and Kailon Rivera, will miss his smile, laugh, and dry humor, his Jeopardy-level vast knowledge of the world, his ready-to-go energy, and his inspiring zest for life no matter your age.  His love of science lives on in his three children who all chose STEM careers, particularly his daughter, Susan, who is an innovator like her dad, currently working in the area of artificial intelligence.  

He is survived by his son Gregory and his wife Jennifer Sullivan of Middletown, DE; his daughter Christine Sullivan of Portland, OR; his daughter Susan Sullivan and her partner Joseph Christ of Seattle, WA; his grandson Kirk Sullivan of Colorado Springs, CO; his grandson Mitchell Sullivan and his wife Kenzy Darrah of Middletown, DE; his granddaughter Audrey Sullivan of Portland, OR; and his great-grandchildren Kipp, Klaira, and Kit Sullivan of Aberdeen, NC; as well as his siblings Vicki Sullivan Bergstrom, Daniel Sullivan and Jerry Sullivan. 

Family and friends are invited to visit on Thursday May 21st, 2026 starting at 10:00AM at the Doherty Funeral Home, located at 3200 Limestone Road, Wilmington, DE. A funeral service will begin at 11:00AM. Interment will follow at All Saints Cemetery.

In lieu of flowers, donations in memory of Jim may be made to the Alzheimer’s Association, PO Box 96011, Washington, DC 20090-6011 (https://www.alz.org).

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