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• 2018-12-05 08:04发布了问答

  水晶的晶晶怎么组词

  　

  435人看过

• 2016-04-04 02:45发布了问答

  为什么同一元素的一次特征x射线与荧光x射线的波长相同

  　

  466人看过

• 2011-04-23 21:43发布了问答

  请翻译一下这段英文1，谢谢

  Materials For the present study， the matrix was ABS supplied by Formosa Co. The reinforcements were polyacrylonitrile based high strength CFs. The properties of materials used were given in Table 1. Carbon fibre surface treatment Carbon fi... Materials For the present study， the matrix was ABS supplied by Formosa Co. The reinforcements were polyacrylonitrile based high strength CFs. The properties of materials used were given in Table 1. Carbon fibre surface treatment Carbon fibres were oxidised by boiling in HNO3 under reflux for 5 h (T5120uC). Afterwards， the nitric acid oxidised fibres were washed with distilled water to neutral pH. Fibre surface composition The fibres were characterised by X-ray photoelectron spectroscopy (ESCA 300， Scienta， Sweden) to determine the level of functionalisation of the modified fibres. An initial survey scan was performed to determine the detectable elements， followed by high resolution scans. The entire X-ray photoelectron spectrum was energy referenced to the C1s peak of graphite (bending energy5284?5 eV). Composite preparation Before processing， ABS pellets and CFs were dried in a vacuum oven for 4 h at 80uC. Composites containing 0， 5， 10， 15， 20， 25 and 30 wt-% SCF were prepared by melt mixing in a co-rotating twin screw extruder (Thermoprism TSE 16 TC， L/D:24). The ABS pellets and CFs were fed from the main and side feeders respectively. The molten composite obtained from the die of the extruder was water cooled and pelletised. The extrusion conditions were arranged， as shown in Table 2. The viscosity of the melt containing CFs depends on the viscosity of the polymer matrix as well as the processing temperature. To avoid unfavourable shearing conditions， the melt temperature is kept as high as possible regarding thermal degradation. Before PA6 was blended to promote interfacial adhesion， vacuum drying of the ABS and PA6 pellets was carried out at 80uC for 4 and 12 h respectively. The 0， 10， 20 and 30 wt-% PA6 containing batches were fed through the main feeder to the twin screw extruder. The extrudate was water cooled and chopped into small pellets. The produced ABS/PA6 pellets were vacuum dried again at 80uC for 12 h. To prepare the SCF reinforced ABS/PA6 composites， the blend was introduced into the twin screw extruder from the main feeder， and SCFs were fed from the side feeder. The twin screw extruder was operated at the same processing conditions used during the blend preparation. The extrudate was again water cooled and chopped into small pellets. The extrusion grades of resin were used to make the extrudate form fully. The specimens for the mechanical characterisation experiments were moulded using a laboratory scale injection moulding machine (microinjector， model 1998; Daca Instruments) at a barrel temperature of 230uC and mould temperature of 80uC. The injection moulding machine used in this study was a laboratory type microinjector. The principle of the operation is that the preweighed (，2?5 g) raw material is loaded into the cylindrical barrel and allowed to melt at a preset barrel temperature for 1 min.Then the molten plastic is pushed through an injection tip by a piston. 展开

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