Experiment § How to detect molecular weight?
Gel Permeation Chromatography (GPC) is often used to detect molecular weight distribution (Figure 1). The experimental method is first to dissolve the test object in an appropriate solvent and then drive it into the instrument from the sample injection port (B). The pump (A) of the instrument will send the sample to the temperature-controlled column (C). After the sample components are separated, they will be detected by the detector (D). The principle of separation is to use the gel particles filled in the column. These particles have many holes of different sizes (Figure 2). Substances with small molecular weight in the sample will diffuse in many small holes, so it takes a long time to flow out of the column, and there are fewer holes for macromolecules to enter, so they flow out of the column quickly (Figure 3). In other words, the shorter the retention time in the column, the greater the molecular weight, and the longer the lag time, the lower the molecular weight. The lag time of GPC is related to the molecular weight, and the signal size is associated with the concentration of the substance. We use GPC chromatograms for incoming inspection of some raw materials and shipment inspection of some products. Figure 4 is a typical UV gel spectrum. The molecular weights of toluene, monomers A, B, and oligomers are 92, 156, 258, and 2000~3000, respectively. For known substances, the spectrum interpretation is not difficult; but for unknown substances, GPC only provides the characteristics of molecular weight. What does each signal represent? It takes professional knowledge to cooperate with FTIR, GC-Mass, and other instruments to have a reasonable answer.
─Author: Miss Hui-Fang, Lai
Activity § Manufacturing Department education and training
Since 2007, the Manufacturing Department has educated, and trains every Thursday from 8 to 9 am. Classes include machine teaching, external training to internal training, reading experience reports, fire fighting, poison drills, etc. Early courses mainly were static lectures. Later, the colleagues who listened to the lectures were asked to write their experiences. This year, the colleagues who listened to the lectures were asked to give written suggestions and scores to the lecturers, which agitated many sparks. In addition to internal training, more than 550 people in the manufacturing department have received external training in the past three years. They are good students in many training units. TTQS emphasizes planning, design, execution, inspection, and achievement and evaluation of five essential elements. In the past, we didn't know these links. We only implemented them with enthusiasm. What is the most significant result of our recent review of the training in the manufacturing department? Everyone put forward many opinions, but one thing is recognized as the most valuable: training can enable production colleagues to build up engineers' awareness and professional dignity. Want to know what classes we have this year, what the lecture notes and exam questions look like? Please click the link: http://everwide.com.tw/download/Training.pdf
Knowledge § What are the common fillers? What is its role?
Filler definition: For the sake of strength improvement or cost reduction, inactive substances added to plastics are generally called fillers. Typical fillers are calcium carbonate, talc powder, quartz powder, mica powder, alumina, aluminum hydroxide, titanium dioxide, barium sulfate, kaolin, etc. Its functions are as follows: 1. Improve specific properties. For example: reduce hardening shrinkage and thermal expansion coefficient, resist cracking, increase hardness, increase specific gravity, increase thermal conductivity, etc. 2. Improvement of processability. For example: improve viscosity, impart anti-sagging characteristics, provide abrasive cutting, and other properties. 3. Reduce cost considerations. For example: changing the proportion of resin, designing incremental resin, etc. The properties of several fillers are as follows: silver for electrical conductivity; zinc oxide for electromagnetic shielding; alumina for heat conduction; aluminum hydroxide for flame suppression and fire extinguishing; calcium carbonate for cost reduction; barium sulfate for specific reuse; Talc for grinding and processing.
Living § Books for summer work-study students
In recent years, the company has provided Huawei University of Science and Technology with work-study opportunities to have little work experience. We gave each of the 5 summer work students 4 books. The first one is "Winning in Influence." According to research, knowledge, and skills account for only 15% of success factors, and the other 85% are achieved through communication and coordination, establishing cooperative relationships, and using the power of the group to achieve success. We use this book to remind students of the importance of interpersonal relationships. The second book is "the problem behind the problem": I hope that when we face various problems, we will not be confused by the appearance of the problem, and we will not forget responsibility. We should look for the real reason behind the problem and think about what I can do to improve it? Only by understanding individual responsibility and taking the initiative can the problem be solved. The third book, "How Do You Define Yourself?" is the life story of British organization master Han Di. We grew up, go to school, take exams, work to make money, get married, and have children. But why do you want to do this? How to look at these things? It depends on our outlook on life. Schools and society seem to be failing to teach such an important matter. We hope that by relying solely on the book's title, students will not forget to define themselves. The fourth book is "Return to Zero, Start Over." We all have an inferiority complex, sadness, aging, the death of relatives, negative emotions, etc. Compared with the rules of etiquette and rational analysis we have learned, these things are more fundamental: Where do we come from? Where will it go in the future? The positioning of spirituality may be the cornerstone of everything. Understanding the importance of working with others, cultivating a responsible character, thinking about how to define oneself, and knowing the existence of one's soul, are things we want to share with work-study students. Descartes said, "I think; therefore I am." I believe these four books are a beginning, a chance, and a journey of thinking and existence.
─Author: Mr. Jin-Lei, Chen
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