 |
After years of research, Chinese scientists have made a series of significant advances in the preparation and mechanism study of metallic glass, and succeeded in preparing amorphous alloy materials for satellite solar cells and other stretching mechanisms.
Amorphous alloys, also known as metallic glasses, are distinguished from crystals by their special atomic arrangement, exhibiting exceptionally high strength, large elastic deformability, low thermal expansion coefficient, and other specific energies. They have been valued by scientists in various countries and become the most active material sciences today. One of the research fields gestates the third material industrial revolution following steel and plastics. Since the late 1980s, the United States, Japan, and the European Union have all stepped up their support for this area and set up major research projects.
Since 2007, under the support of the Ministry of Science and Technology and the National Natural Science Foundation of China, scientists from Beijing University of Aeronautics and Astronautics, Institute of Physics of the Chinese Academy of Sciences, Institute of Metals, Beijing University of Science and Technology, and Tsinghua University have formed a national "973" program." The project research team of several key fundamental issues for high-performance lightweight amorphous alloys has initiated scientific research in the field of high-performance amorphous alloys.
Zhang Tao, a 47-year-old professor at Beijing University of Aeronautics and Astronautics and the chief scientist of the "973" project, is one of the pioneers of massive non-metallic alloys. In the late 1980s and early 1990s, when he studied in Japan, he discovered and discovered rare-earth-based and zirconium-based bulk amorphous alloys, which became the beginning of the study of bulk amorphous alloys and attracted the attention of the international material community. He also made iron, nickel, copper and other alloys into high-strength metallic glass.
"Compared with the corresponding crystalline alloys, amorphous alloys have high strength, low melting point, good fluidity, etc., and can be formed almost like plastics, enabling the precise preparation of parts with complex shapes in a short process," said Zhang Tao.
In 2003, Zhang Tao returned to the motherland and established an amorphous alloy laboratory at Beihang. In recent years, his team has further discovered a variety of new amorphous alloy systems, and has made progress in the formation mechanism of metallic glass, successfully prepared aluminum, magnesium, titanium and other light alloys into metal glass.
Large-scale solar cell array stretching mechanisms, space probes, disk compression and extension rods and other components are key components of satellites and require high strength and high elasticity. Since China does not have such high-performance materials, these components often rely on imports. Zhang Tao's team successfully prepared amorphous alloy materials for satellite solar array extensions, creating possibilities for applications. In the laboratory, the reporter saw a disc press rod for a satellite solar cell made of titanium-based metallic glass. A 20 cm long spiral disc press rod can be opened up to 2 meters in length.
"This means that China's large-scale solar array, in the future may be inserted with metal glass made of 'Chinese-style wings' to fly into space." Zhang Tao said with pleasure.
Scientists have also used metal glass powders for lubrication and other fields, using their high hardness, high elasticity, and low coefficient of friction to improve the performance of lubricating oils.
“The study of metallic glass is still in its infancy, and there are still a large number of basic and applied issues to be studied.†Zhang Tao said that the research group will conduct more research on aerospace and other fields while strengthening basic research.
Introduction
BMI(Body Mass Index) is a person's weight in kilograms divided by the square of height in meters.
In general, BMI is an inexpensive and easy-to-perform method of screening for weight category, for example underweight, normal or healthy weight, overweight, and obesity.
About Materials and Shape of Case
The BMI calculator is ABS case, PVC coated fiberglass tape.
BMI tape measure has several kinds of case shapes-round shape, heart shape, and drip shape. Today we will introduce this round and biggest one for you.
About Language Version of Wheel Plate
This is the most popular English version.
We have Spanish version and other language versions.
About Tape Sizes
The tape both sides with 150cm, one side for male and the other side for female.
To check your waist size, the tape marked with 3 colors zones (green for healthy, orange for over weight, red for over obese)
There are 2 widths for the tapelines: 13mm and 7.5mm
On the case, there is a wheel which can be rotate. Body height data in cm and inch marked on wheel, and weight data on the case, when we rotate the wheel, we can match the height and weight, then check the BMI arrow point to which section(there are 5 sections:underweight,healthy,overweight,obese and very obese)
For example, you are 160cm height and weight 55kgs, match them, then check the BMI arrow point to healthy.
BMI Categories
Less than 20: Underweight
From 20 to 25: HEALTHY
From 25 to 30: OVERWEIGHT
From 30 to 40: OBESE
More than 40: VERYOBESE
Spanish BMI Tape Measure,Medical BMI Measuring Tape,Body BMI Tape Measure
Wintape Measuring Tape Company , https://www.wintapetape.com