粘胶基碳纤维孔洞形成过程的研究

采用透射电镜摄取了制取粘胶基碳纤维的不同热处理过程中（100～1300℃）纤维内部的也洞分布状况,用小角X-ray散射测定了孔径尺寸和分布比例,对孔洞的变化作了定量分析。结果表明碳纤维部分来源于粘胶原丝,在处理过程中又有新的孔洞产生。     

电容式板材在线测厚仪

文中介绍了基于虚拟仪器概念的电容式板材在线测厚仪,分析了电容测微技术,虚拟仪器、实时数据采集与控制等技术难点。     

几项栽培措施对香料烟生长及产质量的影响

通过田间试验,研究了揭膜中耕、栽植方式和烯效唑喷施等措施对香料烟生长和产、质量的影响。结果表明,揭膜中耕和烯效唑喷施可促进茎的横向生长,降低株高,减小叶面积;栽植方式对香料烟生物学性状影响不大。这些措施可增加烟株干物质量、叶绿素含量、根系活力和根冠比;烟叶总糖含量降低,烟碱和钾含量提高,内在化学成分得到改善,糖碱比趋于协调。与对照相比,揭膜中耕后,烟叶产值提高16.9%,烯效唑喷施浓度以15 mg/kg效果最好,其产值提高7.6%。      

热作用致良性前列腺增生组织对激光的光穿透深度变化的比较研究

【摘要】 目的 研究热作用下人良性前列腺增生(BPH)组织对532, 670, 830和1064 nm的激光的光学特性的变化及其差异。方法 实验采用双积分球测量系统以及反向倍增法获取BPH组织的光学特性。结果 在20℃到80℃的温度范围内,BPH组织对532, 670, 830和1064 nm的光学穿透深度都是随着激光波长的增大而增大的,其对532, 670, 830和1064 nm的光学穿透深度都是随着热作用温度的变化而改变的,随着热作用温度的升高,BPH组织对1064 nm的光学穿透深度的变化显著地较其对532, 670, 830 nm的光学穿透深度的变化都要大得多(P﹤0.05),其对532, 670, 830和1064 nm的光学穿透深度的最大值分别在50, 50, 50和70, 70℃,其值分别为(0.404±0.010), (0.539±0.014), (0.699±0.018)和(5.917±0.148) mm,最小值分别在20, 20, 80和60℃,其值分别为(0.251±0.006), (0.449±0.011), (0.621±0.016)和(1.542±0.039) mm。结论 热作用下BPH组织对不同波长的激光的光学穿透深度的变化的测量结果可为的激光的光热治疗BPH提供一点有益的参考数据。     

瑞士乳杆菌对高达干酪蛋白水解的影响

研究高达干酪在4℃条件下成熟16周过程中瑞士乳杆菌对蛋白水解的影响。制作4个高达干酪样品,2个为对照样品,不添加瑞士乳杆菌;另2个为试验样品,添加瑞士乳杆菌KLDS 1.0432。在干酪成熟过程中每隔一段时间测定pH4.6水溶性氮(SN-pH4.6)、12%三氯乙酸氮(SN-TCA)、5%磷钨酸氮(SN-PTA),并进行SDS凝胶电泳。结果显示:对照样品和试验样品的SN-pH4.6和SDS凝胶电泳没有显著差别,但是试验样品中的SN-TCA和SN-PTA比对照样品高。     

中间主应力对垂直井井壁坍塌压力的影响

运用线弹性本构模型来分析垂直井井壁应力分布,并分别用Mohr-Coulomb准则、Drucker-Prager准则和Mogi-Coulomb准则3个强度准则来计算平谷地应力测量与监测钻孔维持井壁稳定所需的最小钻井液液柱压力。通过对比分析得出考虑中间主应力的作用,会使岩石强度得到加强,使得维持井壁稳定所需的最小液柱压力降低;3个准则得出的最小液柱压力在与深度的对应图中表现出一致的变化趋势,说明3个准则有各自的适用性;比较而言Mohr-Coulomb准则偏于保守,Drucker-Prager准则偏于危险,而Mogi-Coulomb准则要优于前两个准则。     

基于空间关系的手绘草图检索

手绘草图是人类最自然的人机交互方式,在普适计算模式下手绘草图将得到越来越多的应用,手绘草图的检索也成为一个新的课题。本文提出一种高效的草图检索方法,该方法以独立于用户绘制习惯的手绘草图统一表示为基础,以手绘草图空间关系为检索相似度匹配特征,并采用特征点调整的相关反馈机制优化检索结果。实验表明本文提出的方法具有很好的检索效果。     

Instrumental stability requirements for exoplanet detection with a nulling interferometer: variability noise as a central issue

We revisit the nulling interferometer performances that are needed for direct detection and the spectroscopic analysis of exoplanets, e.g., with the DARWIN [European Space Agency-SCI 12 (2000)] or TPF-I [JPL Publ. 05-5, (2005)] missions. Two types of requirement are found, one concerning the mean value of the instrumental nulling function (nl(lambda)) and another regarding its stability. The stress is usually put on the former. It is stringent at short wavelengths but somewhat relaxed at longer wavelengths. The latter, which we call the variability noise condition, does not usually receive enough attention. It is required regardless of telescope size and stellar distance. The results from three nulling experiments performed in laboratories around the world are reported and compared with the requirements. All three exhibit 1/f noise that is incompatible with the performances required by the mission. As pointed out by Lay [Appl. Opt. 43, 6100-6123 (2004)], this stability problem is not fully solved by modulation techniques. Adequate solutions must be found that are likely to include servo systems using the stellar signal itself as a reference and internal metrology with high stability.     

我国主要动力用煤的着火特性试验及分析

利用沉降炉试验系统对41个动力用煤的煤样进行了着火特性的试验研究,并在深入分析煤粉着火的过程及试验数据基础上,提出了直接应用煤质分析数据(工业分析)就可计算煤种的着火特性指标——着火判别指数δ,δ与试验数据的相关系数达到了0.958。     

Effects of Current Density on the Microstructure and the Corrosion Resistance of Alumina Coatings Embedded with SiC Nano-particles Produced by Micro-arc Oxidation

To improve the surface corrosion resistance of the alumina films fabricated by micro-arc oxidation (MAO),Al2O3 coatings at different current densities (5,7 and 10 A/dm 2) were produced on aluminum alloys by adding SiC nano-particles into electrolyte during MAO process.The morphology and phase composition of the coatings were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD),respectively.Furthermore,the corrosion performance of the coatings was evaluated via a three-electrode sys...