番荔枝属不同品种叶表面微形态的电镜观察

应用扫描电子显微镜对番荔枝属九个番荔枝品种的叶表面角质、蜡质、表皮毛、气孔等微形态进行了观察比较.结果显示：它们之间的叶表面表皮毛、角质、蜡质和气孔等微形态均有较大的差异.秘鲁番荔枝、AP杂交番荔枝、无核番荔枝上下表面均具有单列丝状毛,气孔只分布于下表面;普通番荔枝、圆滑番荔枝、粗鳞番荔枝叶表面均无表皮毛;秘鲁番荔枝、AP杂交番荔枝、普通番荔枝、粗鳞番荔枝上下表皮角质呈不规则的岛状突起,而圆滑番荔枝、无核番荔枝表面角质较平,角质膜形状不甚清晰;以上所述番荔枝叶表面都覆盖有密厚的针晶状蜡被;除圆滑番荔枝的气孔有副卫细胞外,其它气孔只有保卫细胞而无副卫细胞;刺番荔枝、山刺番荔枝、牛心番荔枝的叶表皮毛为短棍棒状,其表皮角质细胞呈乳突状或波状突起;山刺番荔枝的棒状毛顶端钝圆,而刺番荔枝与牛心番荔枝的棒状毛顶端尖锐;刺番荔枝和山刺番荔枝只有下表皮才具有棒状毛,其气孔形状近似圆形,孔口略内陷于表皮层,牛心番荔枝表面角质呈不规则波状突起,气孔细长稍突.由于这些不同的叶表面微形态是长期受各物种原产地的气候、环境条件影响所形成的,因此研究番荔枝品种的叶表面微形态结构,对正确引种和推广番荔枝果树种植有着重要的意义.     

12种苜蓿叶片表面微形态结构的比较

应用扫描电子显微镜对苜蓿的12个品种叶片表面气孔、表皮毛和蜡质微形态进行了观察比较.结果显示:不同品种苜蓿叶片表皮气孔开度和密度﹑表皮毛长度和密度、蜡质形态均有较大的差异.4、7和11号品种上下表皮气孔开度比较小;除4号品种叶片的上表皮有表皮毛外,其它品种均无表皮毛的存在,4、5、12号品种的下表皮毛密度较大、表皮毛较长;不同品种苜蓿的上表皮均有蜡质覆盖,且4、9和10号品种蜡质覆盖较密集,下表皮中只有2、4、5、6、7、9号品种存在蜡质,且2、5、6和7号品种蜡质覆盖较密集,叶片表面蜡质出现线状、螺旋桨状、垂直片状、网状和棒状5种形态.气孔的开度和密度及表皮毛的长度和密度、蜡质的分布与苜蓿的抗旱性强弱存在一定的相关性.     

中国栗属植物野生种形态特征分析

栗属植物3个种原产于中国.通过形态学调查和扫描电镜观察,对我国不同分布区域的栗属植物野生板栗、茅栗和锥栗进行研究比较,结果表明,3种栗属植物在树体特征、叶片形状、栗蓬及结实特性等方面存在差异.利用扫描电镜进一步对叶片的表面结构进行观察,发现分布同一地区的野生板栗、茅栗和锥栗在气孔密度与大小方面差异较大,茅栗的气孔开度小密度高、乳状突起数目较多且蜡质层较密集;分布不同地区的野生板栗,贵州野生板栗气孔开度小密度高、乳状突起数目较多且蜡质层密集的覆盖气孔周围.对野生栗属资源的特性研究将为自然分布的野生资源评价和利用提供参考.     

6个灰楸无性系叶片表皮微形态特征比较

为加快灰楸高抗品种选育进程,优化灰楸引种栽培管理方案.本研究采用扫描电镜技术对灰楸6个无性系叶片表皮微形态进行了观察.结果表明:灰楸无性系间表皮蜡质纹饰特征、蜡质纹饰分布量、气孔器类型、气孔器尺寸等微形态特征均有较大差异.07027、07028和07069无性系气孔器长度和宽度均较大,07027和07069无性系蜡质纹饰呈细条状,且分布量明显小于其他系号.07032和07040无性系气孔尺寸和开度较为适中,蜡质纹饰呈皱褶粗条状,大量密集于气孔器周围.此外,07032和07040无性系具有明显的气孔下陷特征.07029无性系气孔尺寸显著最小,蜡质纹饰分布较多,但非腺毛分布较为稀疏.根据与抗性相关的叶片解剖形态特征综合评价了灰楸无性系抗逆性,发现07032和07040无性系叶片微形态表现出优良的抗旱或抗寒能力,初步认为07032和07040无性系为灰楸优良高抗无性系.     

钡铁氧体厚膜的制备工艺研究

采用丝网印刷方法来制备钡铁氧体(BaFe12O19)厚膜,研究了轧制时间和取向磁场强度对BaFe12O19厚膜样品的微观结构和磁性能的影响规律。结果表明,随着轧制时间的增加,所制BaFe12O19厚膜样品表面的气孔数量和大小都逐渐减小,且剩磁比和矫顽力均逐渐增加;随着取向磁场强度的增加,厚膜样品中晶粒的分布具有各向异性,且剩磁比和矫顽力均随取向磁场强度的增加而逐渐增加。     

对杯状细胞分泌方式的扫描电镜观察

本文应用扫描电镜对家兔气管、支气管、十二指肠、回肠与胆囊上皮内杯状细胞的分泌方式和过程进行了观察。发现在休止期杯状细胞表面低于其相邻的上皮细胞,顶部有长而密集的微绒毛。以后随分泌颗粒的形成和增多,逐渐向细胞顶端转移、集聚并压挤细胞顶部的细胞膜,使之逐渐向外膨出,微绒毛亦相继变短、变粗、数目减少终于消失。在细胞表面的细胞膜上出现小孔。然后胞膜局部下陷,小孔增多,状如筛孔,最后细胞表面变平。根据上述现象推断杯状细胞是以胞吐方式进行分泌,其表面微绒毛起到膜储备的作用。     

扫描电镜下9种卷柏叶表皮特征的系统学意义

应用扫描电镜观察卷柏属(Selaginella)9种植物的叶表皮。结果显示:表皮细胞长条形或不规则多边形;垂周壁平直或波状;叶缘具或不具明显的刺结构;表皮细胞附属有鳞片状、颗粒状及瘤状突起等;气孔器多为不规则型,其大小、数量、分布及孔口是否光滑,气孔带是否有瘤状突起分布等特征在不同种间存在差异,尤其对卷柏属植物的表皮附属物瘤状突起进行了细致的观察,统计并测量其类型、分布、数量及大小,首次将其应用于卷柏属植物的分类鉴定中。为探讨种间亲缘关系提供更具针对性的微形态学资料。     

黑龙江苹果亚科植物叶表皮形态结构的研究

利用扫描电子显微镜对黑龙江苹果亚科14种植物叶表皮微形态进行比较研究。结果显示:(1)叶表皮细胞呈多边形或无规则形,垂周壁式样呈平直或弓形、浅波纹、深波纹;(2)除无毛花楸无表皮毛外,其它均具有表皮毛,类型均为单细胞不分支非腺毛;(3)叶表皮纹饰呈均匀分布蜡质纹饰和仅气孔周围有蜡质条纹;(4)气孔器均在下表皮分布,且气孔器类型为轮列型、无规则型或不典型辐射型;气孔外拱盖为单层或双层,内缘近平滑或不规则波状;保卫细胞两极仅在水榆花楸、毛山楂、黑果栒子和全缘栒子中出现"T"型加厚。研究表明,该亚科下5属间的叶表皮微形态特征存在一定差异,属内种间在气孔器、表皮毛以及表皮纹饰特征上存在一致性,为属间的系统分类和演化提供了形态结构的依据。     

镁/铝异种金属激光焊气孔形成原因研究

为了研究镁/铝异种金属激光焊接焊缝气孔的形成原因,对1.8mm厚AZ91镁合金和1.2mm厚6016铝合金板材进行了激光搭接焊试验。利用场发射扫描电镜及自带能谱仪,对镁/铝异种金属焊缝中存在气孔缺陷的平均区域、内部不同区域、周围区域以及母材的微观形貌与元素的分布情况进行了研究。结果表明,元素蒸发烧损、残留母材表面的氧化膜以及母材中存在的原始微气孔是镁/铝异种金属激光焊气孔产生的主要原因;采用添加材料激光焊接技术抑制元素蒸发烧损,焊前清除镁板和铝板上下表面的氧化膜,消除镁合金板材原始氢微气孔,是防止镁/铝异种金属激光焊气孔缺陷产生的重要措施。该研究对获得低气孔率镁/铝焊接接头及提高焊接质量是有帮助的。     

紫茎泽兰器官表面微形态的观察

紫茎泽兰为世界性的恶性杂草，严重影响了世界30多个国家的农、林、牧、副业的发展。本文利用扫描电子显微镜和光学显微镜对紫茎泽兰的茎、叶、花、果实及种子等各种器官表皮微形态特征进行了比较观察。结果表明：气孔器分布于叶的远轴面、茎表皮和总苞片的远轴面，其中在叶的远轴面上具两型性气孔器。单列多细胞表皮毛在叶的远轴面、茎表皮、总苞片的远轴面和花瓣的远轴面均有分布。具两列柄细胞的腺毛分布于总苞片的远轴面，而具单列柄细胞的腺毛见于花瓣的远轴面和茎表面。在花瓣的近轴面和柱头表面有长乳突状细胞。通过对其不同器官表面微形态性状的进一步统计分析表明，各种器官的表皮细胞大小、气孔开口度与间距、表皮毛与乳突状细胞的长度及间距等均存在显著性差异。上述观察结果，为进一步探讨外来恶性杂草紫茎泽兰的生态分布和生活习性，以及检疫部门鉴定该种植物提供重要依据。     

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.     

满江红叶片形态特征的环境扫描电子显微镜活体观察

为了克服水生植物含水量高,形貌容易变化的问题,本文利用环境扫描电子显微镜对水生蕨类植物满江红（Azolla imbricata）的形态结构进行了活体观察。满江红枝条顶端的叶片交互式覆瓦状排列,叶片圆形,几乎无气孔。位于茎中部和下部的叶片,2列互生,叶片对折抱茎,具有气孔。满江红叶片边缘具分泌细胞,幼叶的分泌细胞外具许多方形的盐结晶体,老叶的盐结晶体则脱落。结果发现,满江红具有向体外泌盐的功能。     

六种城市行道树叶表皮重金属元素含量及形态结构的研究

利用扫描电子显微镜(SEM)和X-射线能谱仪(EDS)对哈尔滨6种城市行道树叶表皮重金属(铬、镍、锌、铜、铅、镉)含量和形态结构特征进行了观察和分析。结果表明:交通流量大的路段、交通流量相对较小的路段、公园中的行道树叶表皮重金属含量(Cu、Zn除外)呈下降趋势;垂榆(Ulmus pumila var.pendula)中Cr元素含量较高,榆叶梅(Prunus triloba)Ni元素的含量较高,旱柳(Salix matsudana)Cd元素含量较高,小叶丁香(Syringa microphylla)和紫丁香(S.oblata)Pd元素含量较高。行道树叶表皮具有脊状突起和不规则排列的气孔;仅旱柳下表皮蜡质表层较厚;家榆(U.pumila)具有纤毛,小叶丁香具有腺毛,榆叶梅具有单细胞不分支的毛。通过对行道树叶表皮的重金属元素含量分析及形态结构的观察,探讨了城市行道树对重金属元素颗粒吸滞能力,为城市防污绿化树种的选择、生物监测和环境质量评价提供科学理论依据和参考价值。     

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.     

肉豆蔻科（Myristicaceae）3属国产种类的叶表皮形态观察

利用光学显微镜和扫描电子显微镜观察了肉豆蔻科（Myristicaceae）国产3属9种植物的叶表皮,研究各种的叶表皮细胞形状及垂周壁式样、表皮蜡质纹饰及表皮毛的具体特征,测量并统计了气孔器类型、气孔密度等指标。结果显示：所观察的种类表皮细胞排列都很整齐,表皮细胞多边形或不规则形,垂周壁垂直或呈波状。表皮细胞覆盖角质层且仅远轴面具气孔,气孔器类型多为平列型,2～5个副卫细胞,在红光树属发现4气孔或5气孔集生的现象;有些种具星状毛。肉豆蔻科植物气孔器、角质层纹饰和表皮毛特征在属之间差异比较明显,可以作为划分属的重要依据,具有重要的分类学意义。     

Optical Properties and Crystallization of Natural Waxes at Several Annealing Temperatures: a Terahertz Time-Domain Spectroscopy Study

The thermal analysis and optical properties of paraffin wax, beeswax, and liquid paraffin annealed at variable temperatures have been conducted using terahertz time-domain spectroscopy (THz-TDS) coupled with SEM methods. The characteristic optical properties of natural waxes can be used to analyze natural wax adulteration. The lamellar structure of paraffin wax and beeswax grew by a sheet of chain expansion. Furthermore, the crystallization process of paraffin wax can be assigned: rotator-solid transition and liquid-solid ones. According to the temperature-dependent refractive index curves, the refractive index of paraffin wax varies from large to small followed by rotator-liquid transition, untreated one, and liquid-solid one, respectively. The results indicated that THz-TDS has been proved to be of great potential in identification the crystallization of waxes.