Zhang Qinglian, inorganic chemist and educator. Engaged in teaching and scientific research of inorganic chemistry for a long time. He has profound attainments in isotope chemistry and is the founder and pioneer of stable isotope discipline in China. He played an important role in the development and production of heavy water and lithium isotopes in China. In his later years, he studied the determination of atomic weight by isotope mass spectrometry. The atomic weight of indium measured by 199 1 year is114.818 0.003, which has been adopted as a new international standard.
Zhang Qinglian was born in a well-off family in Tangzhi Town, Changshu County, Jiangsu Province on July 3 1908. 14 years old, admitted to Suzhou Taowu Middle School, which is attached to St. John's University and once ranked first in the school's Chinese and English competitions. 1926 when I graduated from high school, I could have gone straight to the university for free because of my excellent grades. However, the patriotic teachers and students left school and set up a private Guanghua University because the American president insulted our national flag at 1925. This patriotic action was supported by Zhang Qinglian, who gave up the opportunity of free admission to St. John and was admitted to Guanghua University. Considering that he can find a job in a middle school and start a small chemical industry after graduating from the chemistry department, he chose chemistry. It took him only three and a half years to complete the required credits at Guanghua University, and he won the silver cup award with the first place when he graduated.
After graduating from college, Zhang Qinglian taught in Changshu Xiaoyou Middle School for one year. 193 1 was admitted to Tsinghua University graduate school. At that time, he saw the shortage of inorganic chemistry talents in China, so he chose inorganic chemistry as his major. Under the guidance of Professor Gao Chongxi, he completed three research papers on rare elements: inorganic synthesis, analysis and identification, and physical and chemical measurement. Finally, I got Geng Fund to study abroad at public expense with excellent results. Since many early American chemists had studied in Germany, he decided to go to Germany for further study. /kloc-in the autumn of 0/934, he entered the Department of Physical Chemistry of the University of Berlin. Since he has been studying in a domestic university for 13 semesters, he only needs to register for 3 semesters according to German regulations. He studied under inorganic chemist Li Sen ·e·H· Riesenfeld and then American Nobel Prize winner H·c· Yuri, which caused great shock in international academic circles because of the discovery of heavy hydrogen and the production of heavy water. According to Zhang Qinglian's existing scientific research foundation, Li Sen Felt suggested that he take the study of heavy water as the topic of his doctoral thesis. After he bought the first batch of heavy water products from Norway, he immediately began to measure the critical temperature of heavy water. Micro-method was used at that time. The inner diameter of the glass capillary is 0.3 mm, the constant temperature is 645K, and the pressure in the tube is above 20 MPa. The sealed pipeline often breaks, which brings difficulties to the experiment. Under the guidance of his tutor, he worked hard day and night to complete the determination of the critical temperature of heavy water in a short time. However, it seems an abnormal phenomenon that the freezing point and boiling point of heavy water are higher than that of light water, while the critical temperature of heavy water is 2.7℃ lower than that of light water. This result was published in the German Journal of Physical Chemistry in the spring of 1935, and was verified by another German scholar with the exact constant method four years later.
Zhang Qinglian published the two-phase density state diagram of light water and heavy water in the whole temperature range, which was quoted by the book Isotope Chemistry (1957) by Buloczky of the Soviet Union. He carefully designed an experiment. By comparing the vapor pressure difference between light water and heavy water, he observed that the vapor pressure difference had a turning point at 498K, and revealed the essence of this abnormal phenomenon. This paper is published at the same time as similar research work independently carried out by American laboratories, which verifies each other.
In order to measure the vapor pressure of semi-heavy water and heavy oxygen water, it is necessary to establish a method for simultaneous analysis of these two kinds of replacement water. He normalized deuterium with hydrogen sulfide and measured the density difference by float method to determine the density before and after normalization. The data of semi-heavy water and heavy oxygen water below 100℃ measured by this method, together with the vapor pressure data of heavy water, later became an important scientific basis for the production of heavy water by distillation.
/kloc-0 In the winter of 935, Zhang Qinglian collected snow water samples from Berlin and Sweden, and determined the contents of semi-heavy water and heavy oxygen water for the first time. It is observed that the content of semi-heavy water and heavy oxygen water is lower than that of ordinary water, and the difference of snow content is greater than that of rain content. On this basis, he put forward the distribution theory of hydrogen and oxygen isotopes in all walks of life of the earth for the first time by consulting the isotope content data of substituted water in rivers, lakes, oceans and plants, which had a far-reaching impact on later experiments and theoretical research.
During the two years of heavy water research in Zhang Qinglian, * * * published 10 paper, and the work with American laboratory colleagues constituted the classic literature of early heavy water properties research. When publishing articles, Li Sen Felt and Zhang Qinglian both showed a humble style, contending to put each other's names before their own, which showed mutual academic respect between teachers and students.
1936, Li Sen Felt was persecuted by the Nazis, and his teaching post was revoked, but Zhang Qinglian still insisted on doing research with him. In June of that year, Zhang Qinglian received a doctorate. Li Sen Felt was forced to leave Germany to work in the Institute of Physical Chemistry of the Science College of Sweden University. Zhang Qinglian went to Sweden as a visiting scholar and worked as a colleague for another year. He used gas mixture as simulated isotope mixed gas and studied the diffusion separation through the membrane wall.
During the three years of studying in Western Europe, Zhang Qinglian learned a lot from the lectures of many authoritative scientists, such as M Bodenstein, the founder of chemical kinetics, and O Hahn, the Nobel Prize winner. He listened to the academic reports of visiting first-class scientists, including Nobel Prize winners, in Berlin and the award-winning reports in Sweden. He also visited the laboratories of three winners G.Hertz, T.Svedberg and K.M.Siegbahn, as well as the famous Cavendish Laboratory in Cambridge and the Curie Radium Institute in Paris. These academic activities had an important influence on Zhang Qinglian's dedication to science and his continuous achievements in becoming a famous chemist and educator.
When Zhang Qinglian was in Sweden, he received a telegram from Zhuang Changgong, director of the Institute of Chemistry of Academia Sinica, and was hired as an associate researcher. This appointment was decided by Zhuang Changgong after reading his article in a magazine, which is very rare for a young man who has never met before. Therefore, Zhang Qinglian fully demonstrated his qualities and talents as a scientist in his early scientific research work.
1July, 937, Zhang Qinglian returned to Shanghai via the Atlantic Ocean, North America and the Pacific Ocean. It was at the beginning of Japan's invasion of China that the Institute of Chemistry was forced to stop working. Zhang Qinglian borrowed the laboratory of Guanghua University in the concession to study the synthesis of various complexes. The following year, he was hired as a professor by Guanghua University. He supervised the graduation thesis of two fourth-grade students, one was to synthesize complexes, and the other was to determine the solubility of sodium chloride in the mixed solution of light water and heavy water at 25℃ by semi-micro method. Both papers have achieved good results.
During 65438-0939, two professors left their posts, so the Chemistry Department of The National SouthWest Associated University, Kun hired Zhang Qinglian as a professor. He took office in Kunming via Vietnam. At that time, although many famous domestic scholars were concentrated in the National The National SouthWest Associated University, the conditions were very difficult and it was difficult to carry out scientific research. However, Zhang Qinglian, together with two Chinese and English research assistants assigned to him by Yang Shixian, head of the Department of Chemistry, used 1 10 grams of heavy water brought back from abroad and some timely glass instruments to complete two papers on the properties of heavy water. One of them is to raise the temperature for measuring the density of heavy water to 50℃ for the first time, which corrects the hypothesis that there is a maximum density near this temperature in the literature at that time. At the same time, two papers on the hydrodynamic effect of heavy water have been completed. In order to determine the normal boiling point of pure heavy ethanol hydrolyzed by aluminum ethoxide, a set of constant pressure device was made. However, the pure test solution at that time was only 1 ml. It requires skilled skills and orderly operation steps to read the data at the moment when the reading of the standard thermometer remains unchanged. He personally completed this determination and accurately determined the boiling point and density of heavy ethanol for the first time. This result has been included in byers Da Ji's Handbook of Organic Chemistry.
1943, under the difficult conditions caused by the war, all scientific research work in the Department of Chemistry of National Southwest Associated University was forced to stop. When Wu Xiang, who was in charge of academic exchanges between China and the United States, asked for a paper, he immediately promised to hand it in within three months. He thinks that the distribution constant of iodine in carbon tetrachloride and water at 25℃ is the classic data quoted in textbooks; If heavy water is used instead of light water, it is meaningful to study the isotopic effect of this distribution constant. So I installed a thermostat and did an experiment on iodine concentration every two days. One day, Rosty Yi prepared the equipment, took a pot of boiling water to the laboratory, and injected it into the thermostatic bath to make the water temperature reach the required temperature quickly. After constant temperature, the sealed tube was rotated to reach equilibrium, then 2ml of heavy water phase and 1ml of organic phase were taken out, and their iodine concentrations were determined with calibrated sodium thiosulfate solution, and the distribution constant of light water and heavy water changed to 85∶ 103, which fulfilled their promise as scheduled.
While working in National Southwest Associated University, Zhang Qinglian also instructed a teaching assistant of Guanghua University to measure the molar freezing point reduction constant of heavy water for the first time. Instruct a teaching assistant of Central University to complete the synthesis of complex. He synthesized the papers on heavy water published at home and abroad and wrote the book "Research on Heavy Water", which won the second academic prize of the Ministry of Education of the National Government 1943. At the same time, Wang Zhuxi, Wen Yiduo and other four professors of the General Assembly also won this honor.
1946, Tsinghua University moved back to Beiping to resume his studies, and the chemistry museum in the school was ransacked by the Japanese invaders. In this case, Zhang Qinglian still insists on scientific research. He and his teaching assistant raised the temperature range for measuring the density of heavy water to 95℃ and extended it to 100℃ for the first time. The paper on the accurate data obtained was originally sent to the British magazine Nature according to the newsletter, but the editorial department turned it into a text column, which showed the importance of this work.
1949 after the founding of People's Republic of China (PRC), Zhang Qinglian's teaching and scientific research activities received great attention and support, and achieved fruitful results.