正交试验法优化马兰头叶蛋白的提取工艺研究

采用碱提酸沉法从马兰头中提取蛋白质。在单因素试验的基础上,采用L9(34)正交试验设计,研究pH、温度、水解时间和料液比对马兰头蛋白提取率的影响。结果表明,在各影响因素中,影响程度依次为:pH>温度>水解时间>料液比,碱法提取马兰头蛋白的最佳工艺条件为:pH 9.0、提取温度50℃、水解时间60min、料液比1︰25(g/mL),在此条件下测得马兰头蛋白提取率为75.86%。     

八角茴香提取物对长角扁谷盗的触杀和驱避活性

为开发环境友好的植物源杀虫剂,以3种有机溶剂采用冷浸法对八角茴香干果中的生物活性物质进行提取,采用滤纸药膜法测定提取物对长角扁谷盗成虫的触杀和驱避活性.结果表明:处理剂量越高,试虫死亡速度越快;用148.63 μg/cm2剂量处理72 h后,甲醇、乙酸乙酯和石油醚提取物对试虫的致死率分别为87.85％、90.98％和94.44％;甲醇、乙酸乙酯和石油醚提取物处理长角扁谷盗成虫72 h后的LD5o分别为28.21、23.51和19.23 μg/cm2,触杀效果依次为:石油醚提取物＞乙酸乙酯提取物＞甲醇提取物.提取物的剂量越高,其驱避作用越大;在各提取物剂量为123.46 μg/cm2时,对长角扁谷盗处理72 h后的平均驱避率以乙酸乙酯提取物最高,达73.22％,驱避等级为Ⅳ级.     

Schllkopf手性试剂的合成工艺研究

介绍了Schllkopf手性试剂的合成工艺,以D-缬氨酸为原料,经保护,氯甲酸叔丁酯活化后,与甘氨酸甲酯盐酸盐反应得甲基-N-（叔丁氧基羰基）-D-缬氨酸甘氨酯;酯加热成环后,与三甲氧嗡四氟化硼盐反应得Schllkopf醚,总收率为51.8%。     

加热条件和轧制过程温度对35K盘条组织的影响

盘条表层的魏氏组织是35K冷墩盘条冷镦开裂的主要原因.为控制表层魏氏组织,首先在实验室模拟了加热炉的加热时间和均热温度,然后根据实验室的研究结果在工厂进行了不同轧制过程温度的试验.试验结果表明:当在加热时间80～90min、均热温度1160～1230℃、终轧温度820～840℃和吐丝温度800～820℃的条件下,所获得的盘条组织均匀、表层魏氏组织小于1级,有效地防止了冷镦开裂.     

关于用Protel 99 SE 绘制Word文档电路图的研究

本文针对电子类专业教师在用Word编辑类似考试试卷文档时,所面临的电路图难画问题,提出了利用Protel 99 SE电路设计软件画电路图,而后再将电路图调入word中的一种比较实用的图文混排方法。     

超声波辅助提取马兰叶中黄酮物质的条件研究

采用超声辅助乙醇提取马兰叶黄酮类化合物,最佳工艺条件为:乙醇体积分数80%,料液比1∶50(g/mL),提取温度30℃,提取时间40 min,颗粒度60目,提取3次。在此条件下,提取率达9.56%。该方法具有操作简单、提取时间短、提取率高,适于马兰叶总黄酮的提取。     

C10-polyacetylenes as allelopathic substances in dominants in early stages of secondary succession

cis-Dehydromatricaria ester (cis-DME) inSolidago altissima, andcis-matricaria ester (cis-ME),trans-matricaria ester (trans-ME), andcis-lachnophyllum ester (cis-LE) inErigeron spp. show strong growth inhibitory effects on other plants. Thecis- andtrans-DMEs were found in soil at the border ofS. altissima communities in concentrations that were inhibitory to test plants. Among four species ofErigeron, the most dominant plant,E floribundus, showed the highest concentrations of the esters. From the results of our experiments, we conclude that these polyacetylenes are probably allelopathic substances with ecological importance.     

大孔树脂纯化马兰总黄酮树脂吸附特性及工艺的研究

研究大孔树脂纯化马兰总黄酮树脂吸附特性及工艺条件及参数。文中分别进行静态吸附、静态解吸、静态吸附动力学过程(Lagergren准一级动力学方程)、静态吸附等温曲线(Langmuir和Freundich等温吸附方程)、动态吸附实验,从7种大孔树脂中筛选用于马兰总黄酮分离的最佳树脂,并系统研究最佳大孔树脂分离纯化的吸附性能和最优洗脱参数。结果表明:D101型大孔树脂为分离马兰黄酮类组分最佳树脂,其分离的最佳工艺为总黄酮浓度为9.36 mg/mL的样液,以3 BV/h的流速,控制pH值为4～5上柱,用75%乙醇以3 BV/h用量进行洗脱,可获得样品总黄酮纯度达70%以上。     

Lax-Phillips scattering theory and well-posed linear systems: a coordinate-free approach

We give a further elaboration of the fundamental connections between Lax-Phillips scattering, conservative input/state/output linear systems and Sz.-Nagy-Foias model theory for both the discrete- and continuous-time settings. In particular, for the continuous-time setting, we show how to locate a scattering-conservative L ²-well-posed linear system (in the sense of Staffans and Weiss) embedded in a Lax-Phillips scattering system presented in axiomatic form; conversely, given a scattering-conservative linear system, we show how one can view the space of finite-energy input-state-output trajectories of the system as the ambient space for an associated Lax-Phillips scattering system. We use these connections to give a simple, conceptual proof of the identity of the scattering function of the scattering system with the transfer function of the input-state-output linear system. As an application we show how system-theoretic ideas can be used to arrive at the spectral analysis of the scattering function.     

Schätzung der Entwicklungskosten von objektorientierter Software

Eingegangen am 29.04.1995, in überarbeiteter Form am 17.01.1996