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21.
22.
特征X射线能谱法测定Fe^+注入小麦种子的深度 总被引:5,自引:2,他引:3
用110keV Fe^+离子束垂直注入小麦种胚后,在扫描电子显微镜上沿种子纵沟剖面,在不同深度上测量Fe元素被激发出的特征X射线强度分布,结果表明分布呈指数衰减,与晶体中的热扩散分布相类似,并对此进行了讨论。 相似文献
23.
含氟聚酰亚胺的辐射交联及其交联度的XPS表征 总被引:2,自引:0,他引:2
含氟聚酰亚胺(FPI)是一种耐高温、耐水解的新型聚酰亚胺。到目前为止,尚未见文献报道它的辐射交联。本文发现它能在高温辐射下交联,交联后的含氟聚酰亚胺的玻璃化转变温度以及高温力学性能有明显提高。本文还首次用XPS方法做了它的交联度表征。用XPS方法求得FPI的凝胶化剂量为50Mrad。 相似文献
24.
Calcining of the mixture of BaCO3 and TiO2 with a ratio 1:4 at different temperatures was carried out to synthesize BaTi4O9 powders. Phase evolution of the samples was studied using the differential thermal analysis (DTA) and X-ray diffractometry
(XRD). Both techniques confirmed that the formation of BaTi4O9 started around 1000 °C. The XRD peaks showed that BaTi4O9 was most pronounced at 1250 °C. X-ray line broadening methods were employed to study the variation of particle size and microstrain
of the BaTi4O9 powders. The Voigt function in a single line and the pseudo-Voigt function in the variance methods were used in our case.
We found that both functions resulted in the same trends, i.e., the particle size increased with the temperature with the
biggest size of 180 and 160 nm, whilst the microstrain yielded the opposite trend with the lowest values of 6.2 × 10–3 and 1.1 × 10–3. The scanning electron microscopy (SEM) study revealed the size of the large particles formed, due to agglomeration, to be
about 0.5–1.9 μm. Furthermore, it was shown that irregular shapes of BaTi4O9 powders necked to each other appeared at 1000 °C and grew into ellipse and rod shapes at 1250 °C.
Electronic Publication 相似文献
25.
本文阐述了一种新型的X射线聚束装置─—X射线透镜的聚束原理。给出了透镜的基本设计方法,并对它应用于X射线光刻研究领域的前景作了展望。 相似文献
26.
The hydration phase and pore structure formation in the blends of sulfoaluminate-belite cement with Portland cement 总被引:1,自引:0,他引:1
Sulfoaluminate-belite (SAB) cements are an attractive class of low-energy cements from the viewpoint of saving energy and releasing less CO2 into the atmosphere during their production. Their hydraulic activity, however, does not match that of the ordinary Portland cement (PC) and needs improvement before they can be used on their own. However, SAB cements when blended with PC have the potential to be used effectively in traditional applications as shown by this study. Mortars made with blends of SAB cements and PC, and a cement-to-sand ratio of 1:3 by weight and a water-to-cement ratio of 0.5, indicate a superior protection against corrosion of steel to those made with blends of PC and blast-furnace slag (BFSPC). The prepared mortars were stored at 20 °C for 90 days under either a 60% relative humidity (RH)-dry air, or 100% RH-wet air conditions. With further improvement in the SAB cement quality through better understanding of their characteristics, a genuine competition between SAB/PC and BFSPC can be expected in practice. 相似文献
27.
Qing YangKaibin Tang Chunrui WangJian Zuo Daoyuan ZhangYitai Qian 《Thin solid films》2003,436(2):203-207
SnS2 films have been deposited on glass and alumina plate substrates by the reactions between an organotin precursor [tetrabuyltin, (CH2CH2CH2CH3)4Sn] and carbon disulfide in n-hexane at the temperature range 180-200 °C for 10-40 h. The reaction system was oxygen free and applied at a moderate temperature. The films so prepared were characterized by techniques of X-ray diffraction, Scanning electron microscopy, Raman and Mössbauer spectroscopies. The films deposited on glass as well as on alumina plate have an average thickness of 30 μm, but have different rose-like morphologies, which are influenced by both the anisotropic growths of crystals and the different substrate structures. Photoluminescence measurements show that the films have an emission peak at approximately 590 nm. 相似文献
28.
Kazufumi Ogawa 《Polymer International》1992,28(1):25-33
Studies have been carried out on KrF excimer laser light (EX), X-ray or electron beam (EB) induced polymerization of 10,12-pentacosadiynoic acid (PDA) Langmuir-Blodgett (LB) films in relation to molecular density or molecular arrangement of the films using X-ray diffraction analysis, infrared (IR) spectroscopy and Raman spectroscopy. The molecular arrangement or density of the PDA LB films was controlled by subphase conditions when the films were built up, such as pH, temperature of a subphase or salt concentration in the subphase. Polymerization sensitivity of the PDA LB film was affected by the arrangement or molecular density. On low density (A type) films the polymerization occurred by irradiation with EX, X-ray or EB, but on high density (B type) films the polymerization occurred only when the irradiation was carried out by high energy beams such as X-ray or EB. Decomposition of polymerized films was observed further by excessive irradiation of EX or X-ray, but not on the B type films. It was revealed by X-ray diffraction analysis that in the A type film, the PDA molecules bent to a larger extent than those in the B type film and the polymerization proceeded topochemically, that is, the thickness decreased little after EB irradiation in a helium atmosphere. On the other hand, in the B type film, the thickness decreased by about 10% as a result of EB irradiation. By IR reflection-absorption (RA) and Raman measurements, it was confirmed that conjugated diacetylenic bonds disappeared and conjugated double and new conjugated triple bonds appeared after high energy beam irradiations. These results support the supposition that 1,4-polymerization, i.e. polydiacetylene type polymerization, occurs easily in the A type film and 1,2- or 3,4-polymerization, i.e. polyacetylene type polymerization, occurs in the B type film, and that the polymerized A type film was decomposed at the polydiacetylenic bond when the irradiation continued further. It was also shown that the polyacetylene type polymer was obtained only when the B type film was irradiated with the high energy beam. 相似文献
29.
The LiPO3-Y(PO3)3 system has been studied for the first time. Microdifferential thermal analysis (μ-DTA), infrared spectroscopy (IR) and X-ray diffraction were used to investigate the liquidus and solidus relations. The only new compound observed within this system is LiY(PO3)4, melting incongruently at 1104 K. An eutectic appears at 4±1 mol% Y(PO3)3 at 933 K. LiY(PO3)4 crystallizes in the monoclinic system C2/c with a unit cell: a=16.201(4) Å, b=7.013(2) Å, c=9.573(2) Å, β=125.589(9)°, Z=4 and V=884.5 Å3, which is isostructural to LiNd(PO3)4. The infrared absorption spectrum indicates that this salt is a chain polyphosphate. 相似文献
30.
The degradation behaviour of Kodar [poly(1,4-cyclohexylene dimethyl-eneterephthalate)] was investigated in air using thermogravimetry, differential thermal analysis and wide angle X-ray diffraction studies. The rates of crystallization and degradation were influenced by thermal exposure and polychromatic irradiation (Λ > 290 nm) for different time intervals. The crystallinity changes (Xc%) and activation energies (ΔE) for the systems have been determined. 相似文献