Experimental § Ultrasonic vibration cleaning machine
There are many ultrasonic vibration cleaners on the market, and similar products are also commonly found in household appliances in addition to industrial use. The key to the cleaning performance of the ultrasonic oscillator is the combination of the bottom of the stainless steel sink and the vibration head. Most of this place uses epoxy resin to closely fit the two together, and after the vibrating head is energized, a high-frequency shock wave is generated, and then transmitted to the bottom of the sink through the resin, so that the water in the sink can generate high-frequency vibration to achieve the effect of cleaning items ( Picture left, cleaning tank and shaking head). The characteristics of the resin are very important, because it needs to have good shock wave conductivity in order to efficiently transmit the shock wave without losing too much power, and in addition, it must also have good temperature resistance and insulation resistance because, in that way, it can be ensured that there is no danger of electric shock caused by the leakage of trace current during use. Especially in the absence of water and air heating, the temperature of the shaking head may rise to 160°C! Many cheap resins have lost their adhesion at this time, which will cause the vibration head to fall. We have developed a special adhesive for ultrasonic cleaning machines and the performances are better than those on the market, especially the high-temperature reliability, which greatly improves the safety of the cleaning machine.
─Author: Mr. Geng-Chang, Shi
Activity § Continuous trials and trials
This August is really stressful enough! TS16949, which has worked hard for a long time, enters the final stage: First, the consultant teacher will do a mock audit for us. Next, the certification company conducts an initial document review on us. Auditors go to the company to inspect the actual documents, which is completely different from the ISO9001 method. Fortunately, there are not many documents that need to be revised. The document review has been successfully passed, and the certification is expected to be carried out for 3 days in early October. The next day, we accepted an audit in English from a Japanese customer, and colleagues who knew a little bit of Japanese and English participated in it. In addition to documents, customers also go to the production line to learn about them, and they will give suggestions on the shortcomings and continue to encourage us: "You are doing a good job!" Everyone is very nervous to pass these trials and discover areas for improvement. For a whole month, we are almost dying of heat. Let's meet for a rest during the Mid-Autumn Festival, and work hard until October after eating moon cakes!
Knowledge § Comparison of the characteristics of free radicals and cations
In addition to free-radical polymerized acrylic system light-curing adhesives, cationic polymerized epoxy resin-based light-curing adhesives have also been promoted in many fields. Cationic polymerization and the aforementioned radical polymerization are very different in reaction characteristics. The characteristics of free radical polymerization: the life of free radicals is very short, only about tens of ns (10 minus 9 seconds). In other words, the light-curing resin of the acrylic system will generate free radicals to polymerize when the light is illuminated, and the free radicals will disappear immediately when the light is stopped, and no further reaction can be made. The characteristics of cationic polymerization: the light-curing resin of the epoxy system will produce cations to polymerize when illuminated, and the cations will not disappear immediately when the light is stopped. The life span of cations can be as long as two or three days after the light is stopped. The cations generated during illumination will continue to react within a certain period of time after the illumination is stopped to improve the properties of the cured product, and the temperature can also be increased to achieve the purpose of post-curing. This feature is called live polymerization. As for the ability of living polymerization, it is closely related to the composition of the formulation and can be observed by DSC.
Living § "True Fresh" or "Fake Fresh" (1)
At the end of July, I took sixth-grade children to Yilan to participate in the one-week national exhibition of primary and secondary subjects, which is the annual science education event.
Our topic is: "True Fresh" or "Fake Fresh" ~ The truth about fruits and vegetables washed at 50℃ to keep them fresh. I chose this topic because a customer sent me a document that the Japanese scholar Mr. Ichimasa Hirayama suggested that washing at 50°C can prolong the preservation of fruits and vegetables, and he also mentioned that washing corn and tomatoes at 50°C can increase the sweetness. Is it possible to extend the freshness of fruits and vegetables washed at 50℃? As soon as I hear this argument, I call it impossible! The climate in Taiwan is hot and humid, if washed with water at 50°C, it will rot, but why is the Internet spread so prevalent? When I talked about this to my child, my son said, "You will know the answer by experimenting!" So we started. First, I asked my colleague to buy eight cooking-related books published by this Japanese scholar on the Internet, and I also asked friends who understand Japanese to help us study and explain. During the experiment with my son, I accidentally discovered that Taiwan's Aiwen mangoes really have "warm soup treatment" after they are harvested because the mango contains anthracnose spots, it can kill germs without harming the flesh after being treated in a warm soup at 50°C for 1 minute, which can really extend the freshness. Figure 1, 2 and related documents are from the 72nd issue of Tainan District Agricultural Information Monthly: http://www.everwide.com.tw/manuals/news72.pdf After having the documentary proof, we took red amaranth for the experiment. After washing with 50℃ warm water for 1 to 2 minutes, then put it in the refrigerator for 14 days. Leafy vegetables that have not been washed or washed at 25°C have withered long ago (photo 3, right), but red amaranth washed at 50°C is still very vital (photo 3, left). Regarding the experiment, there is more interesting sharing, and I look forward to it.
─Author: Miss. Miao-Ling, Lin
