Insight Into the Ultrastructure of Antennal Sensilla of Mythimna separata (Lepidoptera: Noctuidae)

The oriental armyworm, Mythimna separata (Walk), is one of the most serious pests of cereals in Asia and Australasia. The structure and distribution of the antennal sensilla of M. separata were studied by scanning electron microscopy and transmission electron microscopy. The results showed that antennae of both female and male M. separata are filiform in shape. Three groups and seven morphological sensillum types were recorded in both sexes, including uniporous sensilla (sensilla chaetica), multiporous sensilla (sensilla trichodea, basiconica, coeloconica, and styloconica), and aporous sensilla (sensilla squamiformia and Böhm bristles). S. trichodea, which were the most abundant sensilla, was made of three subtypes (ST I, ST II, and ST III) according to external features and two subtypes of s. basiconica (SB I and SB II) and s. coeloconica (SCo I and SCo II) were identified, respectively. Sexual dimorphisms in sensilla of M. separata were mainly perceived as the variations in the numbers of several sensilla subtypes. Also, the possible functions of the antennal sensilla were discussed. These results contribute to our understanding of the function of antennae in the behavior of M. separata.     

寒地油豆角花粉电镜观察与聚类分析

油豆角(Phaseolus vulgaris L.var.chinensis Hort.)是我国北方的"名优特"蔬菜。通过扫描电镜法来观察油豆角孢粉的不同形态,并应用数量分类方法分析油豆角遗传背景差异,油豆角育种提供参考依据。对东北地区主栽油豆角的20个品种的花粉进行扫描电镜观察,并用SPSS软件对观测到的6个亚显微性状进行聚类分析。结果表明,20份花粉分为三角形和近球形两类。花粉赤道轴长在27.43～58.78μm之间,属于小型花粉。萌发孔膜有突起和凹陷两种,覆盖纹饰主要是网孔纹饰,有的孔内有颗粒状附属物。聚类分析把供试材料分为四组,其中玻璃脆豆(7号)与其他油豆角的亲缘关系最远。     

4种禾本科小麦族植物微观形貌特征比较研究

[目的]研究小麦族4种植物花粉粒和气孔的微现特征的异同,并探讨花粉粒和气孔大小与染色体组倍数的关系。[方法]通过扫描电镜对二倍体长稳偃麦草、中阍偃麦草、普通小麦、和八倍体小偃麦的花粉粒和叶表面的微观形貌特征进行了比较。[结果]4种植物在花粉粒形态、大小、表面突起,萌发孔和叶表面气孔大小方面存在一定的差异,其中二倍体长穗偃麦草与其他3种植物的花粉粒和气孔的微观特征差异明显。可见,小麦族二倍体物种与六倍体物种、八倍体物种在花粉粒和气孔的微观特征方面有明显差异,但六倍体和八倍体物种之间差异不明显。[结论]用花粉粒和气孔的一些微观特征作为鉴别二倍体和六倍体、八倍体等染色体组倍数相差较大的物种有一定的依据。     

大型铁路轴承表面变质层研究

应用显微硬度、光学显微镜、X射线衍射、SEM及 AES等,分析与研究了大型铁路轴承(197 726)表面变质层的成分、组织与残余应力,发现变质层中硬度的变化与磨削热产生的相变及表层碳量下降有关,表面存在很大残余压应力,但分布不均匀。     

Visitors’ and residents’ perceptions of urban forests for leisure in Washington D.C

While there is an increasing number of studies on the experience of urban forests, few have examined the similarities and differences between first time visitors, repeat visitors, and local residents in their perceptions of urban forests for leisure. This study fills this research gap using Analysis of Covariance (ANCOVA) and Structural Equation Modeling (SEM), based on data collected on-site from a year-long survey of 1090 participants in Washington D.C. Results indicate that participants are generally positive on urban forests’ value for leisure and are highly satisfied with their leisure experience in the city, with “beliefs in parks and gardens” and “beliefs in street trees” being assessed the highest and lowest, respectively. The study also finds that interaction effects do exist between gender, season, location, and past experience, suggesting respondents’ visiting experience with urban forests is multidimensional, contextual, and situational. Specifically, the older the respondents are, the more positive their responses would be. A location with diverse and dense urban forests is more likely to stimulate positive perceptions, particularly for first timers. In addition, residents tend to focus on recreational aspects of urban forests as opposed to visitors, especially repeaters who are more likely to value the visual and aesthetic aspects of urban forests. This is not only evidenced by the ANCOVA results whereas fall and summer, the best seasons for pursuing outdoor activities, are highly positively perceived by residents, but also by the SEM analyses which show that street trees significantly contribute to repeaters’ satisfaction via their perceptions of “leisure value of urban forests” while no such relationship exists for first timers and residents. Urban parks and gardens are found to significantly and positively contribute to respondents’ visiting experience, which, in turn, leads to satisfaction for each respondent group. Finally, research limitations and theoretical, methodological, and managerial implications are discussed.     

五指毛桃花粉扫描电镜样品的制备

采用离心法和双固定临界点干燥法对五指毛桃(FicussimplicissimaLour)的花粉进行了制样研究.结果表明,双固定临界点干燥法效果较理想,花粉形态非常清晰、饱满、立体感强.     

Effects of amylose content,cooling rate and aging time on properties and characteristics of rice starch gels and puffed products

This study aimed at investigating the effects of amylose content (AC) of 0.12–19.00% w/w on dry basis, cooling rate (1, 3, 5, and 9 °C/min), and aging time (24, 48, and 72 h) on structure, physical properties and sensory attributes of rice starch-based puffed products. They had an influence upon the crystalline type, and the relative crystallinity (RC). The thermal and physical properties of starch gels were also determined. Amorphism was found for starch gels with 0.12% AC. The polymorphisms (B and V) and differential scanning calorimetric endotherms were found for those with AC ≥4.00%. The RC, retrogradation enthalpy (ΔH_r) and gel hardness increased with AC and aging time. The cooling rate did not affect RC, but increased ΔH_r and gel hardness. The higher AC and aging time resulted in higher hardness, fracturability, crispiness and bulk density, but lower expansion ratio and less oiliness of the puffed products. The hardness, fracturability, crispiness and bulk density of puffed products were well correlated with the RC of starch gel.     

特种经济动物纤维超微结构的研究

以银狐、蓝狐、南貉、美洲貉、紫貂、水貂为试验材料,观察特种经济动物狐、貉、貂毛绒纤维的超微结构,利用扫描电镜法比较其鳞片层结构特征。结果显示:银狐针毛翘角平均值为34.6°;鳞片高度平均值为10.88μm,鳞片厚度平均值为0.48μm,银狐绒毛翘角平均值为25.3°,鳞片高度平均值为11.59μm,鳞片厚度平均值为0.51μm;蓝狐针毛翘角平均值为33.1°,鳞片高度平均值为15.09μm,鳞片厚度平均值为0.63μm,蓝狐绒毛翘角平均值为25.0°,鳞片高度平均值为9.80μm,鳞片厚度平均值为0.55μm;南貉针毛翘角平均值为35.1°,鳞片高度平均值为14.54μm,鳞片厚度平均值为0.67μm,南貉绒毛翘角平均值为32.7°,鳞片高度平均值为16.41μm,鳞片厚度平均值为0.65μm;美洲貉针毛鳞片高度平均值为6.05μm,鳞片厚度平均值为0.26μm,美洲貉绒毛翘角平均值为25.5°,鳞片高度平均值为13.04μm,鳞片厚度平均值为0.51μm;紫貂针毛鳞片高度平均值为10.18μm,鳞片厚度平均值为0.54μm,紫貂绒毛鳞片高度平均值为9.24μm,鳞片厚度平均值为0.52μm;水貂针毛鳞片高度平均值为11.50μm,鳞片厚度平均值为0.60μm,水貂绒毛鳞片高度平均值为22.33μm,鳞片厚度平均值为0.59μm。不同种的动物纤维具有独特的形态特征,在超微结构上存在明显的差别。不同种的动物纤维,其鳞片翘角、鳞片高度、鳞片厚度差异显著(P<0.05),同一种动物纤维其针毛与绒毛的鳞片翘角、鳞片高度、鳞片厚度差异显著(P<0.05)。     

甘蔗渣制取活性炭的强度和稳定性研究

以甘蔗渣为原料,采用ZnCl2活化的方法制取生物活性炭。通过对比得率和碘值,优化了制取活性炭的活化剂浓度、炭化温度和炭化时间,并通过X射线衍射（XRD）、扫描电镜（SEM）和比表面积测定等仪器分析试验,探讨了活性炭制取过程中对强度和吸附稳定性的主要影响因素。结果表明,制取吸附稳定性好、强度高的活性炭优化条件为：活化剂ZnCl2浓度为2.0 mol·L^-1,活化剂与甘蔗渣的质量比为5∶1,活化时间为24 h,炭化温度为500 ℃,炭化时间为50 min,以N2作为保护气,流量为2.5 L·min-1。在上述条件下制得的活性炭的碘值为510 mg·g^-1,得率为35.4%,比表面积为653 m^2·g^-1,均孔径为2.4 nm,孔体积为 7.1×10^-2 cm^3·g^-1,可广泛应用于各种水处理领域。     

响应面法优化核桃青皮色素棉织物染色工艺

[目的]广泛开发具有保健功能的天然染料,选用核桃青皮对棉织物进行染色。[方法]通过紫外扫描图谱研究了核桃青皮染液的热稳定性,响应面法优化不同染液浓度、碱(碳酸氢钠)浓度、时间、温度下棉织物的染色工艺,以未染色棉织物为对照,总色差为指标,最后应用扫描电镜图谱分析棉织物染色前后形貌变化。[结果]核桃青皮染液在100℃内稳定性良好;模型优化的条件为染液浓度70mg/m L,碱浓度3.91%,时间102 min,温度100℃,此条件下,总色差为35.292,各因素中碱浓度是影响总色差值的最显著因素,染液浓度和碱浓度交互作用极显著(P0.01);扫描电镜图显示棉织物染色前后形貌未发生改变;由于媒染剂的络合作用,预媒染染色色牢度比直接染色普遍高1~2级,色牢度均达4级。[结论]响应面法可有效优化核桃青皮染液的棉织物染色工艺。