Everwide newsletter No.466

Experiment § AT-710 Automatic Potentiometric Titrator

Everwide has introduced an AT-710 automatic potentiometric titrator to enhance laboratory analysis efficiency and accuracy. This instrument is applied to the determination of Total Acid Number (TAN), Total Base Number (TBN), Epoxy Equivalent Weight (EEW), Hydroxyl Value (OH Value), and isocyanate group (–NCO) content (Figure 1). The AT-710 utilizes potentiometric titration for analysis. By monitoring changes in ion concentration in the solution via electrodes, the instrument can determine the progress of the reaction. As titrant is added stepwise, the system automatically records changes in both potential and titrant volume. When the reaction nears completion, a significant change in potential is observed, and the system uses differential calculation to precisely identify the equivalence point (Figure 2, blue curve). Taking the acid number determination as an example, the yellow curve illustrates the pH change as a function of the titrant volume. When the curve bends and corresponds to the peak of the blue curve, it clearly indicates that the reaction has reached its endpoint, i.e., the equivalence point. The system then automatically calculates the sample concentration based on these changes, making the analysis both rapid and accurate. We invited technical specialists from the manufacturer to conduct on-site calibration and operational training, covering practical operations such as electrode maintenance, software setup, titrant standardization, and troubleshooting (Figure 3). With the AT-710, our laboratory’s analytical accuracy and interpretation capabilities will continue to advance toward higher precision and efficiency.

   —Ms. Yi-Chen Li

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Activity § Three-day, two-night Jiaming Lake hike

Our company organized a three-day, two-night hiking trip to Jiaming Lake. This route is quite challenging and is open only to colleagues with prior hiking experience. A total of 12 people joined this adventure. We gathered at 3 a.m. to set off, ensuring we stayed together for safety. The hike was physically demanding, taking us past Xiangyang Mountain and Sancha Mountain, with every step testing our endurance and strength. On the third day, after hiking about 13 km, we finally reached the stunning Jiaming Lake, known as the "Angel's Tears." One colleague joked, “There were moments I wanted to give up, but thanks to everyone cheering me on along the way, standing here and looking back, I realize I’m stronger than I thought!”We also encourage our colleagues to participate in outdoor activities and connect with nature. In December, we’ll be hosting the “One-Day Double Hundred Peaks” event, and we will be sharing exciting moments from that adventure!

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Knowledge § Do thermosetting polymers exhibit shear yielding behavior?

When a material is subjected to stress, it undergoes strain. Once the stress reaches a maximum and then decreases while strain continues to increase, this indicates molecular chain sliding, a phenomenon known as shear yielding. Thermosetting polymers have a network structure. Under tensile loading, molecular chains break, creating voids that develop into cracks, leading to failure; therefore, shear yielding is not observed. However, in compressive experiments, the applied pressure suppresses void formation, allowing molecular chains to slide. As a result, shear yielding behavior can be observed under compression.

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Living § Hobbies often spring from daily life

I’ve always found that interests often come from the little things in everyday life. Back in college, I stumbled across videos of people making their own planners, and I got hooked. Watching them turn everyday life, work, or random sparks of inspiration into story-filled notebooks using photos, stickers, and handwritten notes was so fascinating—I just had to give it a try. That’s when I started to believe in my own hidden artistic side and eagerly dove in, finding my own way to capture life’s little moments. I’d snap photos on the fly, piecing together everyday campus life with pictures and words. Sometimes it was a meal with friends, or just little things around campus. Slowly but surely, I built a journal that felt like a personal record of my youth. I knew that if I didn’t capture these moments, they’d just fade away over time. Before I knew it, my journal was nearly complete. Flipping through it now, it feels like I can step right back into those moments—reliving the laughter, the hard work, and all the little emotions along the way. To me, it’s more than just a notebook; it’s a little treasure chest full of memories. Maybe someday, when I’m older, I’ll open it again and still feel that warmth from my younger years—and be reminded that every seemingly ordinary moment in life is actually worth holding onto.        —Ms. Chun-Ya Chang