The tube spread around strong cooling technology is new technology of the making semisolid slurry and semisolid billet in Semi-Solid Processing. The technologic parameter of its on the A356 Alloy is researched in the ...
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ISBN:
(纸本)9780878492039
The tube spread around strong cooling technology is new technology of the making semisolid slurry and semisolid billet in Semi-Solid Processing. The technologic parameter of its on the A356 Alloy is researched in the article. It is showed by the result of the experimentation: that the fine and form verge on rotundity crystal grain is made at 180L/h and at 640-650 degrees C. It has met all the conditions in the semi-solid processing on semisolid billet. Semi-solid forming technology has been called the "new metal processing technology in the 21st century", which in foreign countries has certain industrial applications. In 1996 in the United States the sales of semi-solid casting was up to 1 billion dollars. But the industrial application in China is almost empty, one of the most important reasons is: the preparation of slurry or billet is too complicated or cost of production is too high, so that semi-solid forming technology in China has suffered serious setbacks on the road of industrialization. According to this situation, we have done a little attempts on manufacturing slurry and billet of semi-solid forming and have developed a new technology of spread around strong cooling whose intellectual property rights belong to us, equipment production is simple and the process is easy to control and the semi-solid slurry is east to prepare continuously. It will be discussed in this paper that process parameters of the single-tube strong cooling impacts on the microstructure of semi-solid
The failure mechanism of lead-free solder interconnections of chip scale package-sized Ball Grid Array (BGA) component boards under thermal cycling was studied by employing cross-polarized light microscopy, scanning e...
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The failure mechanism of lead-free solder interconnections of chip scale package-sized Ball Grid Array (BGA) component boards under thermal cycling was studied by employing cross-polarized light microscopy, scanning electronic microscopy, electron backscatter diffraction, and nanoindentation. It was determined that the critical solder interconnections were located underneath the chip corners, instead of the corner most interconnections of the package, and the highest strains and stresses were concentrated at the outer neck regions on the component side of the interconnections. Observations of the failure modes were in good agreement with the finite element results. The failure of the interconnections was associated with changes of microstructures by recrystallization in the strain concentration regions of the solder interconnections. Coarsening of intermetallic particles and the disappearance of the boundaries between the primary Sn cells were observed in both cases. The nanoindentation results showed lower hardness of the recrystallized grains compared with the non-recrystallized regions of the same interconnection. The results show that failure modes are dependent on the localized microstructural changes in the strain concentration regions of the interconnections and the crack paths follow the networks of grain boundaries produced by recrystallization.
Nano-catalyst was prepared in the lab. Non-thermal plasma was generated by dielectric barrier discharge (DBD). Through nano-catalyst coupled with non-thermal plasma, a series of experiments for toluene decomposition w...
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ISBN:
(纸本)9783037851920
Nano-catalyst was prepared in the lab. Non-thermal plasma was generated by dielectric barrier discharge (DBD). Through nano-catalyst coupled with non-thermal plasma, a series of experiments for toluene decomposition were carried out. Based on reactor input energy density and removal efficiency and energy efficiency and inhibition for O-3 formation, the load amount MnOx catalyst on the surface of gamma-Al2O3 pellets were compared in the experiment. The results show the catalysis performance of 10 wt% MnOx/gamma-Al2O3 coupled with non-thermal plasma resulted in higher removal efficiency of toluene and better energy efficiency. At the same time, 10 wt% MnOx/gamma-Al2O3 operated on a better inhibition for O-3 formation in the gas exhaust.
There are limited treatment options for cartilage defects in clinical practice because of the lack of suitable biomaterials. Here, we evaluated the effects of collagen type II sponge on the articular cartilage repairi...
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There are limited treatment options for cartilage defects in clinical practice because of the lack of suitable biomaterials. Here, we evaluated the effects of collagen type II sponge on the articular cartilage repairing process using a cartilage injury of a rabbit knee joint model. We showed that the home-made collagen type II sponges appeared to have a suitable pore size of 93.26 +/- 38.4 mu m for chondrocyte growth. MRI with H&E staining results demonstrated that the effusion absorption in the collagen type II sponge treated group was quicker than that of the control group. Moreover, sporadic cartilage signals first appeared at 6 weeks in the collagen type II sponge treated group. Safranin O staining and immunohistochemical analysis confirmed that the newly formed cartilage expresses glycosaminoglycan and type II collagen matrix. Using Sirius red polarized light staining, we showed that the newly formed cartilage-like areas from the collagen type II treated group are significantly greater than those of the control group. Taken together, our data demonstrated that the home-made collagen type II sponge is able to promote cartilage repair in the cartilage injury of a rabbit knee joint model. (C) 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 96B: 267-275, 2011.
Objective There are limited treatment options for cartilage defects in clinical practice due to the lack of suitable ***, we evaluated the effects of type Ⅱ collagen sponge on the articular cartilage repairing proces...
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Objective There are limited treatment options for cartilage defects in clinical practice due to the lack of suitable ***, we evaluated the effects of type Ⅱ collagen sponge on the articular cartilage repairing process using a cartilage injury of a rabbit knee joint *** showed that the type Ⅱ collagen sponges generated from our modified method appeared to have a suitable pore size of 93.26 ± 38.4 micron for chondrocyte *** with H&E staining results demonstrated that the effusion absorption in the type Ⅱ collagen sponge treated group was quicker than that of the control group.
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