It is said that large-scale 3D printing technology has been approved by the national acceptance, which indicates the large-scale 3D printing technology shall be applied for the research and production of printing size to the largest high-precision metal parts, such as aero-engines, etc.

It is predicted that such a large 3D printing technology is the most important application of critical engine components in the future, such as metal blades of aero-engines, space rocket fuel pump turbine and other processing requirements of high precision and complex machining of metal parts, including the material of tungsten heavy alloy, aluminum alloy, magnesium alloy, etc. A one-time high-precision molding will be shortened exponentially, so large-scale 3D printing technology is widely used in aero-engine, especially now aerospace equipment requires light weight but high reliability, longer cycle life and lower cost, etc.

At present, Chinese large-scale 3D laser printing technology is a kind of molding technology lying automatic by the metal powder accompanying with the laser melting, simply similar to playing candle. However, subject to the efficiency issue, the large-scale 3D printing technology is still only in the experimental stage but has not been dragged into batch production. Anyway, China has abundant of resource of metal, such as tungsten heavy alloy, aluminum alloy, magnesium alloy, etc., there will be no problem for them to be the leading edge in 3D printing technology. Nowadays, China has made considerable great success in using 3D printing technology for more than 20 products including aero-engines, rocket engines, launch vehicles, satellites, missiles, etc.

There is a lyric that sings: the water took time story away, and changed you and me. This song took many people’s green years, and also changed many faces. Those summer that decorated with braided hair and uniforms skirt, those long streets that the white shoes ever run, those talking and laughing sounded on daddy’s bicycles and those days you tenderly smiled to me when Phoenix flower fallen on your shoulders. All of these had been caught in the pages of heavy books, and soak in the time of formalin became the most permanent specimens in our hearts.

A WO₃–graphene photocatalyst has been developed that can degrade the dye Rhodamine B almost completely in 15 minutes. This is much faster than the degradation times that can be achieved by bare WO₃ or TiO₂. The catalyst consists of a porous WO₃ framework with a graphene film and is directly produced via electrospinning. The authors from China and the USA envision that this potent electrocatalyst can be used in environmental applications for the degradation of pollutants under visible light.

The superior properties of the photocatalyst can be explained by its components and structure. The WO₃ nanoframework efficiently absorbs visible light due to multiple reflections in the pores. A rapid charge transfer to graphene takes place, which avoids charge recombination. Additionally, graphene nanosheets are exposed on the surface. This enables π–π conjugation between graphene and dyes leading to high adsorption rates of the substrate on the catalyst material. These combined properties lead to enhanced dye degradation via photocatalysis.

Scientists proposed that WO₃–graphene composite can be used to address challenges in environmental remediation. In this context, they highlight that the facile preparation of the material via electrospinning is suitable for production on an industrial scale.

It was said that foreign media reported WU-14, a new Chinese hypersonic weapon speculated, had been tested 10 times the speed of sound super weapon by Chinese military on Jan. 9, 2014, whose purpose is to break the U.S. missile defense system.

Atsunori NEGISHI, Terunobu MAEDA
Hazama Corporation.
Technical Research Institute.

Abstract