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141.
微波等离子体处理对杉木表面性能的影响 总被引:18,自引:1,他引:18
为了解微波等离子体处理对杉木表面性能的影响,使用接触角测定评估表面润湿性,使用扫描电子显微镜观测表面处理前后的差异。结果表明,杉木表面轻微波等离子体处理后,接触角下降为零,即使处理条件十分微弱、处理效果仍然十分明显,这表明微波等离子体处理可显著提高木材表面的润湿性,微波等离子体处理使杉木表面形成粗化面,即表面明显有等离子体蚀刻过的痕迹并留下凹凸不平的坑洼,粗化面的形成可能是导致杉木表面接触角下降, 相似文献
142.
143.
利用扫描电镜对茶丽纹象甲(Myllocerinus aurolineatus Voss)(鞘翅目:象甲科)成虫的触角及感器进行了观察,比较研究了雌、雄成虫触角形态、感器分布和数量上的差异.结果表明,茶丽纹象甲雌、雄成虫触角均呈膝状,由柄节、梗节和7个鞭亚节组成,触角上均着生有5种感器,即毛形感器、刺形感器、棒形感器、叉形感器、鳞形感器以及少量表皮孔.其中,鳞形感器和刺形感器的数量最多,叉形感器在已有的象甲科资料中尚未见报道.毛形感器和叉形感器的数量和分布存在着明显的性别差异,主要表现为雄虫触角上毛形感器和叉形感器的数量显著多于雌虫. 相似文献
144.
Tissue architecture and soil fertility controls on decomposer communities and decomposition of roots
Jane Lindedam Jakob Magid Pernille Poulsen Jesper Luxhøi 《Soil biology & biochemistry》2009,41(6):1040-2060
Using complementary techniques we observed great differences in decomposition of mono- and dicot roots (Festuca rubra L., red fescue grass and Trifolium pratense L., red clover) in compost and soil of varying fertility which we attribute both to chemical characteristics and differences in tissue architecture. In our study the lignin contents were equal for the root materials while C-to-N ratios and cellulose-to-lignin ratios were higher in fescue roots. Pictures taken with a scanning electron microscope (SEM) showed that the rippled surface of fescue roots appeared largely intact even after prolonged incubation giving scant support to predominantly cocci bacteria, where an angular grid structure on the surface of intact clover roots rapidly yielded. The clover root cavities became deeper over time and seemed a favourable nest for colonising rod shaped bacteria. In addition the nodules on clover roots were abundantly covered by decomposers early on. SEM pictures as well as bands of microbial DNA from polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) on roots degraded in compost indicate that organisms colonising clover and fescue grass roots are inherently different and to a greater extent connected to the root material than the compost. Respiration data showed that soil fertility compared to root material played a smaller, albeit significant role in determining the decomposition pattern. There was no indication of N limitation in decomposition. On the contrary accumulated respiration was highest from infertile soils and had significantly lower T½ compared to nutrient rich soils, most likely due to a higher maintenance respiration and lower substrate use efficiency of the decomposers. DGGE showed that infertile soils as well as recalcitrant material both led to a larger diversity of decomposers compared to fertile soils or easily degradable materials. All together this study demonstrated a positive relationship between microbial diversity and stress resulting in higher diversity in the recalcitrant the roots and the infertile soils. 相似文献
145.
利用扫描电子显微镜对小麦胚乳发育过程中淀粉粒的形态和成熟胚乳中的A、B型淀粉粒进行观察。电子显微镜扫描结果显示,花后5~10d,糯小麦胚乳中可见到一些体积较小的A型淀粉粒,10~15d以A型淀粉粒数量增多和体积增大为主;B型淀粉粒在花后15d已经形成,但此时B型淀粉粒的数量少;花后20d—成熟前B型淀粉粒的数量和体积逐渐增长。糯小麦成熟籽粒胚乳中淀粉粒的直径分布为0.96~34.92μm。与普通小麦相比,糯小麦A型淀粉粒的形状较扁平;表面没有普通小麦光滑;B型淀粉粒的形状比普通小麦更无规则,且更容易发生聚集现象。另外,发现在A型淀粉粒上有许多孔洞;在5 000倍数下观察,发现这些孔洞结构从A型淀粉粒表面一直延伸到其内部。 相似文献
146.
Plasma treatment is a new physical sterilization technology.In this study the teliospores of Tilletia controversa Kühn(TCK) were treated with plasma,and then observed by Scanning Electron Microscope(SEM).The results showed that the teliospores were broken into pieces.It set up some bases for research on plasma treatment of masses of wheat seeds containing teliospores of TCK. 相似文献
147.
Pierre Laurent Suzanne Dunel-Erb Claudine Chevalier Jacques Lignon 《Fish physiology and biochemistry》1994,13(5):353-370
The aim of this work was to determine the kinetics of the dramatic development of the gill chloride cells (CCs) during adaptation
of the salmonid Oncorhynchus mykiss to an ion-poor environment.
To monitor cell division, the incorporation in the mitotic cell DNA of bromo-deoxyuridine (BrdUrd) was visualized with a monoclonal
antibody. The density of labelled nuclei was used as an index of cellular division (proliferation), concomitantly with morphometry
of phenotypic changes monitored with SEM.
In the filament epithelium, a phase of CC differentiation occurred within 12h after the transfer, followed by a delayed phase
of cell proliferation (48h). In the lamellar epithelium, the present study demonstrates the absence of cell proliferation
after ion-poor water transfer. The conclusion is that proliferation (mitosis) is important in the primary filament whereas
differentiation and migration (from the filament) is the main mechanism for the appearance of CCs on the secondary lamellae.
The present study suggests that cortisol promoted differentiation, but not division, of cells. CCs, presumably premature,
were stained by anti-cortisol monoclonal antibody indicating the presence of cortisol. No mature CCs were stained.
Growth hormone (oGH, ratGH) increased the rate of cell division both in lamellar and filament epithelium. 相似文献
148.
149.
银杏叶表皮发育的扫描电镜观察 总被引:6,自引:0,他引:6
银杏叶表皮发育成熟的方式是由叶基向叶缘逐渐推进的。叶脉处的表皮细胞分化生长明显较其它表皮细胞早,细胞形态也较特化。在表皮细胞分化成熟过程中,上表皮细胞形态变化不大,而下表皮细胞则特化较明显,成熟后外壁形成突起并形成纵向皱褶。气孔的发育过程是:保卫细胞形成后逐渐下陷,同时细胞壁加厚。其后副卫细胞外壁逐渐形成乳关谨指状突起并弯向气孔上方,同时细胞壁逐渐加厚,成熟后形成皱褶。在叶片生长过程中未见到有表皮 相似文献
150.
黄连解毒汤细粉及超细微粉组织特征扫描电镜观察 总被引:1,自引:0,他引:1
目的:比较黄连解毒汤中药细粉和超细微粉形态学上的差异。方法:黄连解毒汤中药分别进行普通粉碎和超微粉碎,利用扫描电镜对两种不同粉碎方式得到的粉末进行观察。结果:超细微粉碎颗粒大小均匀,电镜下观察基本无完整细胞存在。结论:黄连解毒汤经超微粉碎后,粉末颗粒细微均匀,复方均质度明显改善,绝大多数细胞破壁。 相似文献