养分胁迫条件下石斛兰叶片 表面结构的电镜观察

本文运用扫描电镜(SEM)技术，对石斛兰在养分胁迫条件下叶片的表面结构作了扫描观察。发现当养分胁迫时，叶表面角质层花纹发生改变，叶片气孔形状，数量均受养分营养状况的制约。缺S时叶片角质层被剥蚀，缺K时叶片表面有结晶状物质。     

蜂窝移动通信的图表性能分析和智能调整专家系统

综合近半个世纪的研究结果表明，玉米抗旱性是玉米在水分胁迫环境下，体内细胞在结构、生理及生物化学上发生一系列适应性改变后，最终在植株形态和产量上的集中表现。因而在干旱条件下，根冠比、植株高度、叶片大小、叶着生姿态、叶片及叶片的蜡、角质层厚度、雄穗大小和ＡＳＩ等形态特征；叶水热、细胞的渗透调节能力，细胞内ＳＯＤ、ＰＯＤ、ＣＡＴ、ＬＯＸ、ＰＥＰｃａｓｅ和硝酸还原酶活性以及Ｖ－Ｃ、ＧＳＨ和Ｐｒｏ的变化，均     

基于场发射扫描电镜的4种唇形科植物腺毛形态观察研究

目的:对4种唇形科植物叶表面腺毛发育过程中形态结构变化,进一步探讨其内含物释放途径。方法:采用场发射扫描电子显微镜对薄荷、藿香、留兰香、东风菜叶片表面腺毛发育形态进行观察。结果:4种植物叶片表面均分布有盾状及头状两种类型腺毛,两种类型腺毛发育后期均被观察到不同类型形态坍塌,此外薄荷和东风菜盾状腺毛还被观察到有角质层开裂现象。结论:推测4种药用植物腺毛分泌物可能以分子形式直接渗透出松散角质层释放;薄荷和东风菜盾状腺毛内含物还可能通过角质层裂缝释放至植物体表面,该研究将为被毛药用植物腺毛"外在形"与成分"内在质"关系研究提供参考。     

桐油包膜肥料表面及界面微观形态结构的SEM研究

以桐油为主要成膜材料制备了桐油包膜尿素和桐油包膜复合肥料。用扫描电子显微镜(SEM)对包膜肥料的表面、界面及养分溶解释放后的表面进行了微观形态结构研究。结果表明：桐油能很好地分散并渗入尿素和NPK复合肥料的多孔表面形成附着良好的包膜层，在包膜率小于10％时包膜层厚度介于50～150μm之间。桐油包膜层表面具有特征的波纹状形貌，养分溶解释放后在包膜肥料的包膜层表面留下了水和养分溶液进出的凹陷通道。     

大直径硅（111）抛光片表面微结构研究

大直径硅（１１１）抛光片表面微结构研究＊＊国家自然科学基金资助项目贝红斌刘鸿飞（北京有色金属研究总院，北京１０００８８）本文利用自行研制成功的电化学扫描隧道显微镜（ＥＣ－ＳＴＭ）和扫描隧道谱（ＳＴＳ）对不同掺杂浓度大直径ｎ型硅（１１１）抛光片表面微缺...     

月桂醇硫酸钠对裸鼠表皮角质层脂质超微结构的影响

栖居陆地生命的表皮需要一屏障使机体免受机械、物理、化学和生物等因素的侵害，从而维持机体内环境的稳定。而构成表皮屏障功能的重要因素则是位于角质层的角质细胞和细胞间的脂质。研究表明，角质层脂质主要有脂肪酸、胆固醇和神经酰胺，是构成表皮屏障功能的重要因素。本实验旨在通过观察角质层脂质超微结构的变化，阐述表面活性剂月桂醇硫酸钠对表皮屏障功能的影响。     

Sm在GaAs（100）表面的吸附和界面反应的SRPES研究

利用同步辐射光发射研究了Ｓｍ／ＧａＡｓ（１０）界面形成．高分辨的芯能级谱结果表明，在低覆盖度下（＜０．１ｎｍ），Ｓｍ与衬底的作用较弱，形成较突出的金属／半导体界面．当Ｓｍ的覆盖度增加时，Ａｓ和Ｇａ的表面发射峰很快消失，表明Ｓｍ与Ｇａ发生置换反应而与Ａｓ形成化学键．同时，Ｇａ原子会向Ｓｍ膜体内扩散且偏析到Ｓｍ膜表面，而Ａｓ－Ｓｍ化合物只停留在界面区域．当Ｓｍ膜厚度达到０．５ｎｍ时，Ｓｍ膜开始金属化．结合理论模型，文中还详细地讨论了界面形成和界面结构．     

30CrMnSi断口表面的分形特征

３０ＣｒＭｎＳｉ断口表面的分形特征周善民王伟兰胡小波（南昌航空工业学院，南昌３３００３４）断口表面是粗糙的和不规则的，具有近似的自相似性质，可以看成是一种分形结构，分形维数Ｄ是断裂表面分形结构时粗糙度的一种度量。选用３０ＣｒＭｎＳｉ合金钢为研究对象，...     

Si3N4绝缘栅中两种表面基对pH—ISFET器件敏感特性的影响

在表面基模型理论基础上，本研究了含两种表面基的Ｓｉ３Ｎ４绝缘体主其两种表面基的比例系数对ｐＨ－ＩＳＦＥＴ器件敏感特性的影响。在硅西／胺基＝７／３附近时，得到电解液－绝缘体界面势对ｐＨ值的灵敏度最大，且线性响应范围宽。     

雷达罩壁双层FSS电结构设计与选择

研究了双层Ｙ形缝隙谐振表面应用于雷达罩ＦＳＳ设计时罩壁结构的平面波传输特性，分析了讨论了几种不同双层结构频率特性的差异并得到结论，嵌于介质层之间的ＦＳＳ结构可以获得较为稳定的谐振带宽，并且能够有效地缩减双层ＦＳＳ的结构传输系数谐振区域中的凹沟。     

Age-related leaf characteristics of surface features and ultrastructure of Dendropanax morbifera

Age-related morphological and anatomical changes were investigated by light and electron microscopy with juvenile and adult leaves of Dendropanax morbifera. Most juvenile leaves were glossy and palmate with five deep and narrow lobes divided nearly to two-thirds of the leaf base. Adult leaves were thick and possessed three lobes divided nearly to half of the leaf base. Stomata were ovoid and found on the abaxial surface. The epicuticular waxes of the plant included platelets, angular rodlets and threads. Platelets were attached to the surface at various angles. Distinct angular rodlets could be found on either the adaxial or the abaxial surface. Platelets on surface undulations occurred exclusively on the abaxial surface of adult leaves. Juvenile leaves were ca. 150?μm thick and had few intercellular spaces. Adult leaves were nearly two times thicker than juvenile leaves, and showed highly vacuolated cells and large intercellular spaces. The cuticle proper was apparent on the epidermis and showed distinctly alternating lamellate structures in juvenile leaves. The epidermal cell wall of adult leaves was covered with a cuticle layer for which a lamellate structure was not found. These results suggest that the species is heteroblastic in leaf characteristics with increasing leaf age.     

Surface replicas of normal and vitrified leaves of Datura insignis, Barb Rodr

Vitrification is a morphological and physiological disorder affecting plants during their in vitro vegetative propagation. Vitrified plants have a poor survival rate when transferred from in vitro to greenhouse conditions, a fact mainly due to water loss and dissecation. It has been shown that normal and vitreous leaves of Datura insignis differ in the frequency of normal and abnormal stomata. The purpose of this work was to compare the surface of normal and vitreous leaves of D. insignis, using a modification of the platinum/carbon replica method. Adaxial and abaxial leaf surfaces of normal plantlets have a smooth and homogenous cuticle. A granular aspect, probably due to leaf age, rarely occurs at the periphery of the epidermal cells. Both adaxial and abaxial leaf surfaces of vitrified plantlets show discontinuities in the cuticle, occurring at several regions of the outer periclinal cell walls. However, such discontinuities are most noticeable in the region between adjacent epidermal cells. Fibrils 20-30 nm thick show a random arrangement or an oriented pattern in cuticular discontinuities. In D. insignis vitrified plantlets, adaxial and abaxial leaf cuticle has discontinuities or gaps which may cause an increase in cuticular transpiration contributing to the low survival rate of vitrified plantlets.     

Bioinspired Directional Surfaces for Adhesion,Wetting, and Transport

In Nature, directional surfaces on insect cuticle, animal fur, bird feathers, and plant leaves are composed of dual micro‐nanoscale features that tune roughness and surface energy. Here, experimental and theoretical approaches for the design, synthesis, and characterization of new bioinspired surfaces demonstrating unidirectional surface properties are summarized. The experimental approaches focus on bottom‐up and top‐down synthesis methods of unidirectional micro‐ and nanoscale films to explore and characterize their anomalous features. The theoretical component focuses on computational tools to predict the physicochemical properties of unidirectional surfaces.     

稀土元素钕对油菜超微结构的影响

电镜观察表明：低浓度的钕对完全营养培养的油菜顶叶叶尖细胞的叶绿体片层结构有明赤的改善作用,而高浓度的钕会引起结构损坏。适当浓度的钕能对缺钙油菜苗受损的细胞有修复作用,这表明钕有部分替代钙的作用。钕对油菜主根根尖细胞的作用与对顶叶叶尖细胞作用类似,但对根细胞超微结构影响更为明显。     

恶性肿瘤病人放疗与化疗前后头发超微结构的改变

目的:比较放,化疗前后患者头发超微结构的改变,探讨放,化疗对头发表面超微结构的影响.方法:用扫描电镜观察18例患者放,化疗前后头发表面超微结构的改变,其中20例化疗患者分别采用CEF,NP,TP方案治疗,8例放疗患者分别为鼻,咽,喉.结果:放,化疗前,毛小皮细胞排列较规则,细胞表面光滑,无明显侵蚀现象;化疗后,接受CEF,TP治疗者,毛小皮细胞排列较不规则,大多数毛小皮翻翘,破裂,粘连,脱落;而NP治疗者,改变较少;放疗后局部毛小皮细胞排列紊乱,几乎都有不同程度的毛小皮翻翘与脱落改变.结论:放,化疗前后患者头发超微结构有较大的差异,化疗改变程度重于放疗.     

Observations of xenon gas-treated barley cells in solution by atomic force microscopy

Barley cells cut from a sprout were exposed to either air or high-pressure xenon gas for 3 days and the surface of those cells was observed by atomic force microscopy (AFM) to examine the effect of the gas treatment. This method enabled the direct observation of the fresh surface of the barley cells in solution at high resolution. The cuticle layer was preserved on the primary cell wall of 0.48 MPa xenon gas-treated barley cells, while air-treated barley cells lost the cuticle layer from the primary cell wall. These findings indicate that the high-pressure xenon gas treatment is effective to preserve the cuticle layer attached to the primary cell wall. AFM is a powerful tool for the observation of the surface structure of living plant cells in solution.     

木立芦荟发育过程中叶表皮角质膜和蜡质的变化

应用扫描电镜观察了不同发育阶段的木立芦荟叶表面角质膜、蜡质的形态结构。结果显示,在木立芦荟叶发育的早期,叶表面只有一层薄的角质膜,没有蜡质。随着叶的发育,角质膜逐渐增厚,在角质膜表面逐渐形成瘤状蜡质突起。当叶发育成熟时,表面覆盖有厚的角质膜,角质膜上分布有密集的瘤状蜡质。在叶表皮上分布有下陷的气孔,气孔上方的角质膜和蜡质呈筒状围绕在气孔四周。由于木立芦荟叶表气孔下陷,又覆盖着厚的角质膜和密集的蜡质．能有效地减少水分散失和增强叶片反射光辐射的能力,因此,芦荟能适应干旱、强光照的环境。     

CdF_2半导体膜中电子-表面声子强耦合对极化子性质的影响

采用改进的 Huybrechts线性组合算符和变分方法 ,研究了半导体膜内电子与表面光学声子强耦合、与体纵光学声子弱耦合对极化子性质的影响 ,得到了极化子的有效质量和自陷能随膜厚的变化规律 .对 Cd F2 半导体 ,计算了不同支声子与电子的相互作用对极化子有效质量和自陷能的贡献     

Numerical Analysis of Characterized Back Interface Traps of SOI Devices by R-G Current

Characterized back interface traps of SOI devices by the Recombination\|Generation (R\|G) current has been analyzed numerically with an advanced semiconductor simulation tool,namely DESSIS\|ISE.The basis of the principle for the R\|G current's characterizing the back interface traps of SOI lateral p\++p\+-n\++ diode has been demonstrated.The dependence of R\|G current on interface trap characteristics has been examined,such as the state density,surface recombination velocity and the trap energy level.The R\|G current proves to be an effective tool for monitoring the back interface of SOI devices.     

用于先进 CMOS电路的 150 mm硅外延片外延生长

随着大规模和超大规模集成电路特征尺寸向亚微米、深亚微米发展,下一代集成电路对硅片的表面晶体完整性和电学性能提出了更高的要求.与含有高密度晶体原生缺陷的硅抛光片相比,硅外延片一般能满足这些要求.该文报道了应用于先进集成电路的150mmP/P+CMOS硅外延片研究进展.在PE2061硅外延炉上进行了P/P+硅外延生长.外延片特征参数,如外延层厚度、电阻率均匀性,过渡区宽度及少子产生寿命进行了详细表征.研究表明:150mmP/P+CMOS硅外延片能够满足先进集成电路对材料更高要求,