Structural and biochemical mechanism responsible for the stay-green phenotype in common wheat

In order to increase the supply of assimilated carbon to grain, a new stay-green wheat cultivar, Chuannong17 (CN17), with delayed leaf senescence, carrying wheat-rye 1RS.1BL translo- cated chromosome was developed. CN17 exhibited distinct differences in net photosynthetic rate (Pn), chlorophyll (Chl) content, malondialdehyde (MDA) content, activity of both superoxide dismutase (SOD) and catalase (CAT) during the grain filling stage, and flag leaf senescence compared with the control. The new cultivar maintained longer and higher photosyn- thetic competence compared with the control, and this aspect correlated with the difference in chloro-plast development. Moreover, the stay-green pheno-type of CN17 was also observed under natural growth conditions. Consequently, the coordination of the physiological, biochemical, and structural aspects in the stay-green cultivar produced higher seed weights and per-plant yield compared with the control cultivar.     

Development of novel and sensitive sensors based on microcantilever of atomic force microscope

Recently, the development of sensors based on microfabricated cantilevers of atomic force microscope (AFM) has attracted considerable attention from the designers of novel physical, chemical, and biological sensors. Many kinds of sensors have been developed taking the advantages of its high-resolution imaging, force measurement and force sensitivity, such as immunosensor and DNA biosensor and the sensors for detection of intermolecular interaction. This paper reviews the progress made in this field and discusses the signal transfer principles by which the design of the sensors is achieved.     

AB环量子点结构的电子输运

用格林函数方法研究了嵌在介绍AB环一臂中量子点的电子输运性质，数值计算表明：沿着每一共振峰，其输运相位连续的增加π，在两共振峰间的某个位置，其输运相位突然减小π，从而每一共振峰具有相同的相行为，理论结果与实验观测较好的相符。     

Effect of alkyl substitutions on self-assembly

The self-assemblies of 4-hexadecyloxybenzoic acid and 3,4,5-trihexadecyloxybenzoic acid have been studied by using scanning tunneling microscopy (STM). The well-ordered assemblies with different arrangement have been investigated. The structural change is attributed to the different number of substituted alkyl chains on periphery.     

氢原子中电子运动图形的绘制

本文研究了氢原子中电子运动波函数和电子云图像的绘制方法，给出了BASIC语言编写的绘图程序以及绘制的波函数和电子云的立体、等值、界面图。     

钒刚玉光学和磁学性质的理论研究

根据完全对角化方法和一种类晶体场模型 ,统一地解释了α- Al_2 O_3:V~(3 ) 的光谱、电子顺磁共振g因子和零场分裂D值 .理论计算值与实验符合得很好 .此外 ,导出的V~(3 ) 位置的位移量 0 .0 0 86nm与浓缩红宝石中Cr3 位置的位移量 0 .0 0 6nm相接近 .     

多孔氧化铝膜的制备及其表征

在硫酸、磷酸及草酸溶液中 ,通过阳极氧化铝箔制备出了多孔氧化铝模板 ,用阶梯降压法将氧化铝层与铝基底分离 .透射电镜结果表明 :这种膜的孔间距 ,孔径以及晶胞尺寸均随所加氧化电压的增加而增加 .通过 FT- IR谱发现 ,在阳极氧化过程中 ,电解液阴离子也参与了多孔膜的形成 .XRD谱证明形成了无定形氧化铝     

微波ECR等离子体溅射沉积T_t薄膜的结构研究

用电子回旋共振(ECR)等离子体溅射方法在室温基片上沉积出的T_i薄膜的结构是用X RD和TEM进行分析的。结果表明所沉积的T_i薄膜是平均粒径,晶粒尺寸分布很窄的稳定fcc结构。在实验过程中发现可以通过对工作参数的调整控制薄膜的晶粒尺寸。我们还讨论了ECR等离子体对薄膜结构和晶粒尺寸的影响。     

东方杯叶吸虫精巢和精子发生的超微结构研究

本文应用透射电镜研究了东方杯叶吸虫精巢和精子的超微结构及精子发生过程,并与体外培养成虫进行比较,提出一种精子结构模式图。精子的形成经历了由精原细胞,初级精母细胞、次级精母细胞、精子细胞和精子的发育等过程。精子细胞形成后,胞质突起形成一分化区,并发育成精子鞘,核向鞘中旋转、浓缩和迁移,两根鞭毛轴丝由鞘中基体发出;鞭毛为9+“1”结构。体外培养成虫尚有几种不正常的成熟精子,可作为体外培养的评价指标。     

nm级制造用三维微定位的扫描探针显微镜

介绍一种用于ｎｍ级制造具有ｘｙｚ三维微定位能力的扫描探针显微镜（ＳＰＭ）．采用电磁足周期性地夹紧与松开，结合压电陶管的轴向伸缩变形的微位移爬行器构成三维微定位机构．扫描范围可达２０μｍ×２０μｍ，且探针可在样品表面ｘ和ｙ方向上１０ｍｍ×１０ｍｍ范围内实行ｎｍ级的定位．探针在ｚ方向接近样品表面也可自动进行．给出了微定位器的运动分辨率、速度与工作频率，以及在扫描道显微（ＳＴＭ）方法下测得的高定向石墨表面原子图像