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R语言作为GNU系统的一个自由,免费,源代码开放的软件,是一种适合推广应用于统计计算和统计制图的优秀工具.在地球化学大数据的趋势面分析中借助R语言软件,选择spatial库包来进行kriging分析和点模式分析;spatial库中的surf.gls方法用最小二乘法来拟合趋势面;使用anova方法比较多个嵌套模型的拟合优度,实现了趋势面函数模型的最优拟合,计算与绘图自动完成,增强了分析的可靠性.该文以安徽省全椒县中部地区主要商品粮基地215.86 km~2范围内586个土壤样品测试数据为例,通过对Zn, Cu及Zn/Cu比值的趋势面分析,求得三阶趋势面函数拟合度最优,三阶趋势面图形与地质环境条件基本吻合,证实了R语言的应用优势.  相似文献   
2.
邱志勇  潘胜  胡林  刘湘  周鲁卫 《物理学报》1997,46(2):314-323
对两类电流变液的介电性质的测量结果表明,强交流电场下电流变液经历介面极化;而且是一种非线性极化.根据海藻酸钠和NaY沸石电流变液的动态剪切应力与强电场介电谱相似这一事实,确定了这两种样品的流变学响应时间下限,它们分别是1ms和0.7ms.还发现NaY电流变液的动态切应力与非线性三次谐波的强度有关;一种高分子半导体电流变液的流变学响应基本不受样品含水量的影响.对上述实验结果进行了解释 关键词:  相似文献   
3.
The resonance effect of microcrystalline cellulose/castor oil electrorheological (ER) suspensions was studied in a compressed oscillatory squeeze flow under external electric fields. The resonance frequency first increases linearly with increasing external field, and then shift to high-field plateau. The amplitudes of resonance peak increase sharply with the applied fields in the range of 0.17-1.67 kV/mm. The phase difference of the reduced displacement relative to the excitation force inverses in the case of resonance. A viscoelasticity model of the ER suspensions, which offers both the equivalent stiffness and the viscous damping, should be responsible for the appearance of resonance. The influence of the electric field on the resonance frequency and the resonance hump is consistent qualitatively with the interpretation of our proposed model. Storage modulus G' was presented for the purpose of investigating this influence.  相似文献   
4.
沸石电流变液材料的研究   总被引:1,自引:0,他引:1  
系统地研究了沸石的由离子类型、数目、骨架的孔道大小和结构特性对沸石电流变液性能的影响. 证实了阳离子在电场中的迁移所引起的晶粒极化是Y,A和M等沸石电流变特性的基础,指出了较大的孔径和具有足够多易迁移的阳离子是该类沸石具有较好电流变性的的前提.根据NaZSM-5沸石在高电场中与其它沸石表现不同,具有屈服应力大而漏电流小的特点,提出了沸石晶粒极化还可能存在的另一种新的晶格变形机理.  相似文献   
5.
The resonance effect of microcrystalline cellulose/castor oil electrorheological (ER) suspensions was studied in a compressed oscillatory squeeze flow under external electric fields. The resonance frequency first increases linearly with increasing external field, and then shift to high-field plateau. The amplitudes of resonance peak increase sharply with the applied fields in the range of 0.17-1.67kV/mm. The phase difference of the.reduced displacement relative to the excitation force inverses in the case of resonance. A viscoelasticity model of the ER suspensions, which offers both the equivalent stiffness and the viscous damping, should be responsible for the appearance of resonance. The influence of the electric field on the resonance frequency and the resonance hump is consistent qualitatively with the interpretation of our proposed model. Storage modulus G′ was presented for the purpose of investigating this influence.  相似文献   
6.
Six different N-alkyl substituted acrylarnide nonionic hydrogels were prepared and their swelling characteristics were measured. Poly N-isopropyl acrylamide (PNIPA) and poly N-n-propyl-acrylamide (PNNPA) temperature sensitive hydrogels were chosen as the nonionic temperature sensitive hydrogels for concentration of very dilute aqueous protein solution. The separation properties of PNIPA and PNNPA hydr0gels with different network dimensions were studied and the modification of the hydrogels was surveyed in order to decrease their surface adsorption of protein molecules. The experimental results of the concentration of BSA (Bovin serum albumin) dilute aqueous solution by hydroxylpropyl methacrylate (HPMA) copolymerized PNIPA hydrogel were given. The value and the limitation of concentration of dilute aqueous protein solution by this method was evaluated.  相似文献   
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