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31.
含金刚烷聚合物的研究进展   总被引:3,自引:2,他引:1  
含金刚烷聚合物在气体分离、液晶显示材料、通讯技术、微电子、生物医学等高新技术领域已显示出潜在用途。文中对以金刚烷衍生物为单体的聚合物的合成、结构与性能等方面的研究进展做了分析和评述,对这一领域的发展趋势进行了展望。  相似文献   
32.
经对星 119井的压前、二次压裂后测试资料的试井分析 ,评价了高能气体压裂和二氧化碳酸冻胶压裂措施效果 ,确定了压后低产原因是由于储层渗透性差 ,不是油藏改造工艺问题 ,从而为该区的下一步勘探和开发提供科学依据。  相似文献   
33.
在轨航天器执行机构一般具有典型的非线性特性,直接影响飞行姿态控制性能。基于姿态控制系统模型,应用相平面分析方法,建立含继电器和时延两类非线性特性的执行机构开关线模型。以开关线模型为基础,根据相轨迹图求解极限环参数,获得姿态控制的稳态特性。仿真结果表明非线性姿态控制系统特性的计算模型和方法正确、有效。  相似文献   
34.
This paper examines the dynamic relationship between power spot prices and related trading volumes in one of the most emergent energy markets. Traditionally, investigating the bivariate stochastic processes has been dominated by linear econometrical methods that proved helpful especially in finance. However, when dealing with intradaily power data, we cannot rely on models developed for financial or other commodity markets. Therefore, wavelet transforms are applied for power markets data to search for and decode nonlinear regularities and hidden patterns existing between the variables. Given its ability to decompose the time series into their time scale components and thus to reveal structure at different time horizons, wavelets are useful in analyzing situations in which the degree of association between processes is likely to change with the time-horizon. Therefore, a wavelet-based cross-analysis is performed between prices and trading volume time series. On the same basis, causality tests and out-of-sample forecasting tasks are carried out to empirically the strong relationship between the two investigated time series.  相似文献   
35.
SmYbZr2O7 ceramic powders were pressureless-sintered at 1700 °C for 10 h to fabricate dense bulk materials. SmYbZr2O7 exhibited a single phase of defect fluorite-type structure. Hot corrosion tests between SmYbZr2O7 and V2O5 were carried out in an electric furnace at temperatures of 600–1000 °C for 2 h in air, respectively, and the reaction products were investigated using X-ray diffraction, laser Raman spectroscopy and scanning electron microscopy. The final corrosion products were composed of (Sm,Yb)VO4 and ZrV2O7 or m-ZrO2, depending upon the reaction temperature. Hot corrosion mechanisms were further discussed based on the thermal instability of ZrV2O7 at elevated temperatures.  相似文献   
36.
Sar? 85 (Linum usitatissimum L.) linseed variety was used in this study. Linseed was cultivated at 2008 (LS-08) and 2009 (LS-09) without fertilizer. In addition, at 2009 diammonium phosphate [(NH4)2HPO4] and ammonium nitrate (NH4NO3) were applied (LSF-09). The linseeds were analyzed for protein, ash and oil contents and fatty acid compositions. There were differences among harvesting years for oil, protein and ash contents of the seeds. The greater oil and protein contents were obtained during LS-08 compared with LS-09. There were no significant difference in protein and ash content between LS-09 and LSF-09 while a significant difference was observed in oil content. Seed protein, oil and ash contents were significantly affected by the harvesting year, but only oil content was affected by the fertilizer treatment. There are significant differences in palmitic, stearic, oleic, ??-linolenic and arachidic acid between LS-08 and LS-09. While palmitic, stearic, oleic acid decreased, ??-linolenic and arachidic acid increased during 2009 harvesting year. LSF-09 has the highest amount of ??-linolenic acid. The fertilizing treatment seems to have an increasing effect on the amount of ??-linolenic acid, while it has a decreasing effect on the oleic acid content.  相似文献   
37.
The current–voltage (I–V) characteristics of Polypyrrole(PPy)/p-Si/Al structure have been investigated as a function of temperature. A modified Norde function combined with conventional forward I–V method has been used to extract the junction parameters including the ideality factor, barrier height and series resistance. Norde function has been compared with the Cheung functions and it has been seen that there is a good agreement with both method for the barrier height values. However, the values of series resistance have very different especially towards to the lower temperatures. This is attributed to non-ideal I–V characteristics of the Au/PPy/p-Si/Al structure and non-pure Thermionic emission theory due to the low temperature effects.  相似文献   
38.
线材的氧化铁皮起着保护线材免锈蚀的作用,但是也需要在酸洗时容易除去。影响铁皮除去或结合力的主要是铁皮的厚度和其物相结构。通过对不同轧制条件下的氧化铁皮厚度、物相结构进行检测分析,研究了精轧温度和吐丝温度对φ12 mm SCM435氧化铁皮物相结构的影响。研究表明,随着精轧温度或吐丝温度的升高,SCM435线材的氧化铁皮厚度均会增加,且在800-900℃短时间就会生成较厚(约20μm)的氧化铁皮;由于Cr的氧化选择性,精轧温度在870℃以上,吐丝温度在810℃以上时,随精轧温度或吐丝温度升高,氧化铁皮中FeO比例提高;但是吐丝温度高于860℃后,物相结构的变化趋缓,FeO的比例变化不大。  相似文献   
39.
三山岛西岭金矿区位于渤海之滨,与北部海域金矿区相互连接,形成金资源量近千吨的巨型金矿床,矿床为地下与海底开采。区域内断裂发育,分布有NE向和NW向断裂,其中NE向断裂为控矿构造,而NW向断裂多具有不同程度的导水性,对矿床安全开采影响重大。基于矿区地质条件与地球物理特征,采用高精度磁测法和音频大地电磁(AMT)法在矿区东部进行了勘查试验,根据显示的磁性异常与电性异常,在平面上解译了NW向断裂(F-1、F-2)与NE向断裂(F-3、F-4),在L1剖面上解译了4条断裂,在L2剖面上解译了3条断裂。综合判断解译信息,NW向F-1断裂在平面与剖面上都反映良好。同时,与北部海域NW向构造研究资料进行对比分析,结果显示西岭矿区F-1推断断层与北部海域B-F4断层特征一致,吻合较好,推断西岭矿区NW向F-2断裂被F-3断裂错断。研究结果说明综合物探方法在该区域可行有效,为下一步钻孔验证NW向断裂存在,判断断裂富水及导水性质,以及未来矿床开发利用提供了地球物理依据。  相似文献   
40.
To explore the crucial driving forces and dynamics of the Chinese apparel industry cluster, the authors analysed current situations, characteristics and the dilemma in the Chinese apparel industry based on surveys conducted in the Yangtze River Delta. This study classified the factors impacting apparel industry cluster development into necessary conditions and evolutionary factors according to logistic differential equation, and proposed a dynamics model framework of apparel industry cluster with positive and negative feedback mechanism. The authors believe that the Chinese apparel industry cluster is an ecology system involving outsourcing, specialisation agglomerating, competition, resource complementary, etc. and has a quick response ability of adapting to environment.  相似文献   
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