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• 2018-12-10 03:10發(fā)布了問(wèn)答

  碳酸巖的新巖類型

  　

  637人看過(guò)

• 2018-11-29 16:46發(fā)布了問(wèn)答

  X射線熒光光譜儀的指標(biāo)信息

  　

  385人看過(guò)

• 2017-09-25 19:45發(fā)布了問(wèn)答

  x射線衍射的原理及可以解決的問(wèn)題

  要寫(xiě)讀書(shū)報(bào)告，想知道X射線衍射的原理以及可以解決的問(wèn)題。要詳細(xì)點(diǎn)的，別太籠統(tǒng)。謝謝！

  605人看過(guò)

• 2010-03-12 05:24發(fā)布了問(wèn)答

  掃描電鏡和化學(xué)成分分析

  請(qǐng)問(wèn)江蘇省內(nèi)有哪些學(xué)?？梢宰?掃描電鏡和化學(xué)成分分析（EDX或XPS）。

  736人看過(guò)

• 2009-08-12 18:58發(fā)布了問(wèn)答

  電子探針?lè)治鰡挝?

  哪個(gè)單位可以做電子探針顯微分析 主要是低合金鋼焊縫中微區(qū)成分分析

  681人看過(guò)

• 2009-02-19 16:10發(fā)布了問(wèn)答

  高手幫忙翻譯一工科英文??！高分大謝！

  Figure 2 SEM micrographs of worn seat insert surface of engine #6175 after 1474 hours of testing. The arrows and labels indicate the locations of EDX analysis. The same adhesion phenomenon occurs on the valve seat surfaces. Figure 4 show... Figure 2 SEM micrographs of worn seat insert surface of engine #6175 after 1474 hours of testing. The arrows and labels indicate the locations of EDX analysis. The same adhesion phenomenon occurs on the valve seat surfaces. Figure 4 shows SEM micrographs of the worn exhaust valve seat surface of engine #6175 after 1474 hours of testing. The valve material is Stellite 6 faced 23-8N (solution treated and aged). The arrows in Figure 4b indicate the locations of EDX analysis. Note the pits and deposits on the worn seat surface. Figures 5a shows the EDX spectrum of spot A on Figure 4b showing adhered insert material. Note molybdenum and manganese in the spectrum. Figure 5b shows the EDX spectrum of spot B in Figure 4b showing both adhered insert material and oil deposits. Note molybdenum.， phosphorous， chlorine， calcium， and zinc in the spectrum. Other valves from different engines labeled as "adhesion" in Table 2 share this typical adhesive phenomenon. The adhesive wear mode appears to predominate at valve seat interfaces with high asperity contact stresses or high combustion pressure. The surface roughness can contribute to adhesion significantly. Valves faced with Stellite alloy show less adhesive wear than unfaced valves， Table 2. The presence of high melting point phases， such as carbide or ceramic compounds in the contacting materials is believed to help prevent microwelding or adhesion related wear. Shear strain， also known as radial flow， is defined as the first derivative of the displacement， i.e.， . Figure 6 [8]. Shear strain controlled wear can characterized as a surface plastic deformation process. The wear is the result of the shear strain on the seat surface exceeding the plasticity limit of the material. The material is then detached or delaminated from the seating surface as wear particles. The typical appearance of shear strain controlled wear are ridges and/or radial flow of material on valve seats and inserts. Shear strain controlled wear sometimes is associated with adhesion. 展開(kāi)

  425人看過(guò)

• 2008-12-25 07:05發(fā)布了問(wèn)答

  為什么無(wú)線電波能繞過(guò)障礙物，而光波不能？

  為什么無(wú)線電波能繞過(guò)障礙物，而光波不能？為什么晶體可以作為X射線衍射的天然光柵，而普通光柵卻不能？為什么隔著山可以聽(tīng)到中波段的電臺(tái)廣播，而電視廣播卻很容易被高大建筑物擋??？ 我們明天要考的題?。“萃辛?；額?。?！

  808人看過(guò)

• 2008-01-13 08:57發(fā)布了問(wèn)答

  什么是衍射儀?

  　

  364人看過(guò)