Application of EEG multipole model in the diagnosis of Alzheimer''''s disease

In order to find the electroencephalogram （EEG） characteristic parameters typical of Alzheimer＇s disease （AD） and explore an effective diagnostic method, a new mobile current multipole model was proposed to simulate the AD patient＇s cortical dipole source activities. The indicators of goodness of fit （GOF） and DtononD （DD） were calculated from EEG samples to evaluate the performance of this model. Relevant results showed that this multipole model with higher GOFvalues and larger DD change well fitted the pathological electrical activities of cortical neurons aroused by AD＇s extended sulcus and gyrus in the cerebral cortex. Meanwhile, the products of DD mean ＆ standard variance were found in a clear linear correlation with the diagnostic data of mini-mental state examination （MMSE） used in AD clinics. Furthermore, by tracing this multipole model＇s indicators in typical patients and contrasting with the functional magnetic resonance image （fMRI） as AD progressed, we suggested that the DD index may be suitable for monitoring the AD developments as a new diagnostic parameter.     

磁水对玉米幼苗生理生化效应的初步研究

用不同磁场强度（０．０５Ｔ、０．１０Ｔ和０．１５Ｔ）的磁水处理玉米种子、幼苗，发现一定磁场强度的磁水能提高叶片中叶绿素含量、硝酸还原酶（ＮＲ）活性，但降低ＩＡＡ氧化酶活性、呼吸速度和电导率．结果表明：磁水具有增强玉米幼苗进行光合作用、氮代谢和抑制ＩＡＡ降解、提高其抗冻性的效应．     

α－FeOOH超微粒的制备及热处理

利用化学沉淀法制备了α－ＦｅＯＯＨ超微粒，将其在不同温度下于空气氛中进行热处理，并使用ｘ－ｒａｙ衍射和透射电镜及热重分析仪对样品进行了测试与分析．     

Recombination and linkage disequilibrium in Arabidopsis thaliana

Linkage disequilibrium (LD) is a major aspect of the organization of genetic variation in natural populations. Here we describe the genome-wide pattern of LD in a sample of 19 Arabidopsis thaliana accessions using 341,602 non-singleton SNPs. LD decays within 10 kb on average, considerably faster than previously estimated. Tag SNP selection algorithms and 'hide-the-SNP' simulations suggest that genome-wide association mapping will require only 40%-50% of the observed SNPs, a reduction similar to estimates in a sample of African Americans. An Affymetrix genotyping array containing 250,000 SNPs has been designed based on these results; we demonstrate that it should have more than adequate coverage for genome-wide association mapping. The extent of LD is highly variable, and we find clear evidence of recombination hotspots, which seem to occur preferentially in intergenic regions. LD also reflects the action of selection, and it is more extensive between nonsynonymous polymorphisms than between synonymous polymorphisms.     

Rapid reductive degradation of azo dyes by a unique structure of amorphous alloys

An Fe-based amorphous alloy was found to significantly enhance the reductive degradation of an azo dye in aqueous solution. The surface-area normalized rate constant was up to 2.0 L m-2 min-1 at room temperature,an order of magnitude larger than any previously reported value. The activation energy of the degradation process was calculated according to the Arrhenius equation,and a much lower value than those previously reported was obtained. Valence band measurement indicated that a depressed valence band maximum and a widened empty band were established in the amorphous ribbon. The unique structure of the amorphous alloy is important-it may reduce the activation energy of the degradation process and enhance the activity of the electrons,thus accelerating the degradation process.     

一维β-Fermi-Pasta-Ulam纳米单原子链中非线性参数作用的研究

运用发展的Ford-Kac-Mazur方法对一维β-Fermi-Pasta-Ulam纳米单原子链的运动方程进行了简化.通过数值计算,对系统在非线性相互作用下的傅里叶热传输定律进行了修正,同时对奇偶原子数晶格系统的局域能量密度进行了比较,发现奇数原子系统中明显存在离散呼吸子.     

竹子热水预抽提过程中糖组分的溶出规律

研究了不同工艺条件下竹子热水预抽提过程中主要糖类组分的溶出率,总糖和戊糖占抽提液中固形物的比例,以及糠醛、羟甲基糠醛的生成随H因子的变化规律.结果表明:为了获取最大量的糖、减少糠醛(F)和羟甲基糠醛(HMF)的生成量,lgH应控制在3.2～3.4的范围内;在获得相同最大量糖的前提下,热水预抽提的最高温度不应超过160℃;当lgH低于3.2～3.4的范围时,糖的溶出率较低;高于此范围,部分糖降解生成F和HMF,总糖占抽提液固形物的比例和糖组分溶出率下降;在总糖溶出率达到最大值时,相同H因子作用下,温度超过160℃会导致糖降解生成的F和HMF增多.关键词:竹子半纤维素;热水预抽提;H因子;糖溶出率;糠醛;羟甲基糠醛     

表面羟基对Pd/Zno复合材料光催化性能的影响

利用一锅水热法成功地制备了具有不同钯摩尔分数的Pd/ZnO复合物,采用X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、能量色散能谱(EDX)及X射线光电子能谱(XPS)等手段对产物进行了表征。结果表明,所得产物为部分钯颗粒负载在氧化锌的表面,剩余的钯则掺杂到了氧化锌的晶格中。XPS测试表明不同钯摩尔分数修饰的Pd/ZnO复合物中表面羟基发生变化,结合Pd/ZnO复合物光催化性能认为,在反应体系中加入适量的氯化钯溶液,可增加氧化锌表面羟基的含量,也能促进光生电子-空穴的分离,从而提高了Pd/ZnO复合物光降解效率。     

纯铝挤扭过程数值模拟研究

挤扭(twist extrusion,简称TE)工艺是一种通过材料的剧烈塑性变形,获得块体超细晶材料的有效方法。文章运用有限元分析方法对纯铝的TE过程进行模拟,分析速度场分布、等效应变以及载荷的变化规律;并探讨不同背压和摩擦条件对试样应变及载荷的影响。模拟结果表明,背压能显著提高应变量的大小,并能使试样更好地贴模;摩擦的增大能提高应变量,但载荷同时也显著增大。