機械類科普英文文章
隨著全球化的不斷深入，我國技術對外交流不斷增多，對科技翻譯的需求必然日益增多。下面是小編帶來的，歡迎閱讀!
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What is Hydraulic?
A complete hydraulic system consists of five parts, namely, power components, the implementation of components, control components, no parts and hydraulic oil. The role of dynamic components of the original motive fluid into mechanical energy to the pressure that the hydraulic system of pumps, it is to power the entire hydraulic system. The structure of the form of hydraulic pump gears are generally pump, vane pump and piston pump. Implementation of components ***such as hydraulic cylinders and hydraulic motors*** which is the pressure of the liquid can be converted to mechanical energy to drive the load for a straight line reciprocating movement or rotational movement. Control components ***that is, the various hydraulic valves*** in the hydraulic system to control and regulate the pressure of liquid, flow rate and direction. According to the different control functions, hydraulic valves can be divided into the village of force control valve, flow control valves and directional control valve. Pressure control valves are divided into benefits flow valve ***safety valve***, pressure relief valve, sequence valve, pressure relays, etc.; flow control valves including throttle, adjusting the valves, flow diversion valve sets, etc.; directional control valve includes a one-way valve , one-way fluid control valve, shuttle valve, valve and so on. Under the control of different ways, can be divided into the hydraulic valve control switch valve, control valve and set the value of the ratio control valve. Auxiliary components, including fuel tanks, oil filters, tubing and pipe joints, seals, pressure gauge, oil level, such as oil dollars. Hydraulic oil in the hydraulic system is the work of the energy transfer medium, there are a variety of mineral oil, emulsion oil hydraulic molding Hop categories.
Hydraulic principle
It consists of two cylinders of different sizes and composition of fluid in the fluid full of water or oil. Water is called "hydraulic press"; the said oil-filled "hydraulic machine." Each of the two liquid a sliding piston, if the increase in the small piston on the pressure of a certain value, according to Pascal's law, small piston to the pressure of the pressure through the liquid passed to the large piston, piston top will go a long way to go. Based cross-sectional area of the small piston is S1, plus a small piston in the downward pressure on the F1. Thus, a small piston on the liquid pressure to P = F1/SI,Can be the same size in all directions to the transmission of liquid. "By the large piston is also equivalent to the inevitable pressure P. If the large piston is the cross-sectional area S2, the pressure P on the piston in the upward pressure generated F2 = PxS2 Cross-sectional area is a small multiple of the piston cross-sectional area. From the type known to add in a small piston of a smaller force, the piston will be in great force, for which the hydraulic machine used to suppress plywood, oil, extract heavy objects, such as forging steel.
History of the development of hydraulic
And air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdom in 1795 Joseph ***Joseph Braman ,1749-1814***, in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved.
World War I ***1914-1918*** after the extensive application of hydraulic transmission, especially after 1920, more rapid development. Hydraulic components in the late 19th century about the early 20th century, 20 years, only started to enter the formal phase of industrial production. 1925 Vickers ***F. Vikers*** the invention of the pressure balanced vane pump, hydraulic components for the modern industrial or hydraulic transmission of the gradual establishment of the foundation. The early 20th century Constantine ***G • Constantimsco*** fluctuations of the energy carried out by passing theoretical and practical research; in 1910 on the hydraulic transmission ***hydraulic coupling, hydraulic torque converter, etc.*** contributions, so that these two areas of development.
The Second World War ***1941-1945*** period, in the United States 30% of machine tool applications in the hydraulic transmission. It should be noted that the development of hydraulic transmission in Japan than Europe and the United States and other countries for nearly 20 years later. Before and after in 1955, the rapid development of Japan's hydraulic drive, set up in 1956, "Hydraulic Industry." Nearly 20 to 30 years, the development of Japan's fast hydraulic transmission, a world leader. Hydraulic transmission There are many outstanding advantages, it is widely used, such as general workers. Plastic processing industry, machinery, pressure machinery, machine tools, etc.; operating machinery engineering machinery, construction machinery, agricultural machinery, automobiles, etc.; iron and steel industry metallurgical machinery, lifting equipment, such as roller adjustment device; civil water projects with flood control the dam gates and devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power plant installations, nuclear power plants, etc.; ship deck crane ***winch***, the bow doors, bulkhead valves, such as the stern thruster ; special antenna technology giant with control devices, measurement buoys, movements such as rotating stage; military-industrial control devices used in artillery, ship anti-rolling devices, aircraft simulation, aircraft retractable landing gear and rudder control devices and other devices.
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3D列印機制作類骨材料
It looks like bone. It feels like bone. For the most part, it acts like bone. And it came off an inkjet printer***噴墨式印表機*** .
Washington State University researchers have used a 3-D printer to create a bone-like material and structure that can be used in orthopedic***整形外科的*** procedures, dental work and to deliver medicine for treating osteoporosis. Paired with actual bone, it acts as a scaffold for new bone to grow on and ultimately dissolves with no apparent ill effects.
The authors report on successful in vitro tests in the journal Dental Materials and say they're already seeing promising1 results with in vivo tests on rats and rabbits. It's possible that doctors will be able to custom order replacement2 bone tissue in a few years, said Susmita Bose, co-author and professor in WSU's School of Mechanical and Materials Engineering.
"If a doctor has a CT scan of a defect, we can convert it to a CAD file and make the scaffold according to the defect," Bose said.
The material grows out of a four-year interdisciplinary***各學科間的*** effort involving chemistry, materials science, biology and manufacturing. A main finding of the paper is that the addition ofsilicon3 and zinc4 more than doubled the strength of the main material, calcium5phosphate***磷酸鈣*** .
The researchers -- who include mechanical and materials engineering Professor Amit Bandyopadhyay, doctoral student Gary Fielding and research assistant Solaiman Tarafder -- also spent a year optimizing6 a commercially available ProMetal 3-D printer designed to make metal objects.
The printer works by having an inkjet spray a plastic binder7 over a bed of powder in layers of 20 microns, about half the width of a human hair. Following a computer's directions, it creates a channeled cylinder8***圓筒，汽缸*** the size of a pencil eraser.
After just a week in a medium with immature9 human bone cells, the scaffold was supporting a network of new bone cells.
The research was funded with a $1.5 million grant from the National Institutes of Health.