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21.
饲喂不同日粮的山羊尿沉渣晶体的化学组成和显微形态   总被引:2,自引:2,他引:0  
采集饲喂棉饼、玉米粉、麸皮、豆饼四种常见日粮的山羊尿样,应用化学定性分析、X-射线衍射物相分析、X-射线能谱分析和扫描电子显微镜观察等手段分别进行尿沉渣晶体的化学组成和显微形态的分析和观察。结果表明,饲喂棉饼日粮和麸皮日粮时山羊尿沉渣晶体的化学组成为磷酸钾镁,显微开矿为斜方柱状;饲喂玉米日粮时为碳酸镁,形态为长方柱状;饲喂豆饼日粮时为碳酸钙(方解石),形态为短方柱状。最后,还对几种尿沉渣晶体的生成  相似文献   
22.
AIM: To develop the cell model of polymer/liquid crystal and to study the effect of their elasticity on the adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs). METHODS: Using the method of solvent evaporation induced phase separation, the cell model of polymer/liquid crystal was constructed. The surface morphology and phase separation structure were determined by polarized optical microscopy (POM), scanning electron microscopy (SEM) and small angle X-ray scattering (SAXS). rBM-MSCs were separated and expanded by adherent culture. The surface markers of rBM-MSCs were detected by flow cytometry. The cells were induced to osteogenic differentiation and adipogenic differentiation for 2 weeks. After 3 passages, the cells were divided into 4 groups, including total PU control group, 10% membrane group, 30% membrane group and 50% membrane group. The cells were then incubated with rhodamine phalloidin for cytoskeleton staining and were observed under the confocal laser scanning microscope after cultured for 24 h. RESULTS: The cell model of polymer/liquid crystal was constructed successfully using the method of solvent evaporation induced phase separation. Flow cytometry results showed that the rBM-MSCs positively expressed CD29, CD44 and CD90, and negatively expressed CD34 and CD45. After stained with alizarin red S and oil red O, the calcium nodule and lipid droplets in rBM-MSCs were observed obviously. The cytoskeleton staining result indicated that the area in total PU control group, 10% membrane group and 30% membrane group were greater, and the actin microfilaments were also clearer than that in 50% membrane group. CONCLUSION: The cell model with suitable content of liquid crystal made a contribution to the rBM-MSCs' adhesion, but too much liquid crystal inhibits cell adhesion.  相似文献   
23.
Influence of one macromolecule-type retarder bone glue on the setting time, strength, ion concentration in liquid phase and supersaturation degree, crystal morphology of dehydrate and microstructure of hardened paste of building gypsum is investigated. Furthermore, internal cause of strength loss of building gypsum with addition of retarder is analyzed, The results indicate that bone glue could retard the hydration of building gypsum markedly, but its negative influence on the strength of building gypsum is far lower than that of low molecule-type retarders. Bone glue has a minor effect on crystal morphology of dehydrate and porosity of hardened paste, but it causes the large crystal size and coarsening of pore size distribution of hardened gypsum paste, which is the very intrinsic reason of strength loss of building gypsum.  相似文献   
24.
通过20L和1200L云室条件下的检测试验,对微米级和纳米级碘化银的成核率与核化速率进行了统计分析,实验证明纳米级碘化银冻结阂温高且成冰性能好,在人工影响闪电方面是一种较好的消雷催化剂。  相似文献   
25.
Novel 2-amino-4-(4-methoxyphenyl)-6-(piperidin-1-yl)pyridine-3,5-dicarbonitrile is synthesized using malononitrile, 4-methoxybenzaldehyde and piperidine as starting material in methanol by one-spot. The yield is 40% with three-component reaction at room temperature. The structure is confirmed by 1H NMR, MS and X-ray single crystal diffraction.  相似文献   
26.
A novel broadband substrate integrated waveguide bandpass filter was presented based on the highpass characteristics of substrate integrated waveguide(SIW) and the bandstop performance of butterfly radial slot photonic band gap(PBG) structure. In order to verify this idea,a wideband bandpass filter with 4.65 GHz center frequency and 40% fractional bandwidth was designed. The electromagnetic simulation results show good passband characteristics from 3.71 to 5.6 GHz, while the maximun insertion loss is about 0.40dB. An experimental filter prototype was fabricated with standard PCB process and measured by the vector network analyzer. The measured results show that, for the filter prototype, the passband is from 3.78 GHz to 5.76GHz, the fractional bandwidth is about 41%, the minimal insertion loss is about 0.72 dB and the maximun insertion loss is 1.65.dB The measured results are in good agreement with the simulated results.  相似文献   
27.
本文报道了药用植物鸭跖草的根、茎和叶的解剖结构。鸭跖草的木质部为六原型,韧皮部与木质部排列,根皮层中分布有粘液细胞和晶体细胞。其内皮层具凯氏带。茎中维管束散生,许多近表皮薄壁组织细胞中含有分散的或成束的多个晶体,茎中央薄壁组织中含有粘液细胞和单宁细胞。叶为两面叶,叶肉组织分栅栏组织和海绵组织,栅栏组织细胞一层,叶中含有粘液细胞和晶体细胞。  相似文献   
28.
蒙脱土/木材复合材料的结晶性能   总被引:1,自引:2,他引:1  
为了考察蒙脱土/木材复合材料的结晶性能,利用X射线衍射仪检测了以处理木材试样和蒙脱土为原材料、借助酚醛树脂制备的蒙脱土/木材复合材料,并将未处理试材、处理试材及复合材料进行比较后发现,试材经氢氧化钠、微波、氢氧化钠-微波、氢氧化钠-超声波处理后,相对结晶度降低;超声波处理后,相对结晶度增大。除氢氧化钠处理试材外,其他处理试材与蒙脱土形成的复合材料的结晶度均进一步降低。未处理材、处理材及复合材料结晶区晶层间距变化不明显。研究还发现,蒙脱土在复合材料中主要以插层型结构存在。   相似文献   
29.
顺式氯氰菊酯微乳液的微观结构   总被引:2,自引:0,他引:2  
利用粘度法和电导法研究了顺式氯氰菊酯微乳液微观结构的变化,对其形成机理进行了探讨,并用偏光显微镜和透射电镜等手段进行了表征。研究发现顺式氯氰菊酯微乳液体系随水相含量的增加分别形成了W/O型微乳液、层状液晶、双连续结构和O/W型微乳液;表面活性剂和醇分子之间依靠氢键和范德华力形成各向异性的类线形大分子,被破坏和重排是层状液晶结构区显示出异常流变特性和不规则电导率变化的主要原因。  相似文献   
30.
碘化钾-结晶紫体系分光光度法测定水中硒   总被引:8,自引:0,他引:8  
四价硒可以氧化广为和结晶紫形成离子缔合物,在546nm波长处该离子缔合物摩尔吸光系数可达1.3×105。本体系在磷酸介质中可避免Fe3+的干扰。本方法用于水中硒的直接测定。  相似文献   
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