天麻中天麻素的提取工艺

目的考察影响天麻中天麻素的提取因素。方法采用正交试验法,以提取液中醇浸膏收率及天麻素的含量为考察指标。结果提取的最佳条件70℃下,用40%乙醇提取3次,每次2h,6倍量乙醇。结论所用工艺稳定可行。     

真空冷冻干燥超细天麻粉体的研制

真空冷冻干燥(简称冻干FD)是发展近代生物医药工程与中药现代化的关键高新技术,近年来,日本将中国名贵中药天麻制成超细粉体胶囊(粉体中心粒径D50～50μm),用来取代西药治疗失眠,取得很好效果,无毒副作用.据近年研究表明,在中药粉体的中心粒径达到10 μm～15 μm的细度以下时,人体对其有效成份的吸收率将会更好.在此研制的鲜天麻真空冷冻干燥超细粉,按粒子分布曲线(用Mastersizer-2000型激光衍射仪检测)与4000倍扫描电子显微镜检测,其粉体中心粒径高达D50=12.996μm,部分还进入亚微米级.本文对其研制方法、技术、设备及检测质量控制等作了阐述.     

Efficient and accurate waveguide mode computation using BI‐RME and Lanczos methods

In this paper, a special purpose algorithm for solving large eigenvalue problems based on the Lanczos method is successfully applied to an engineering problem: the electromagnetic analysis and design of passive waveguide devices. For dealing with such complex problems, the boundary integral‐resonant mode expansion (BI‐RME) technique has been recently proposed. This technique solves integral equations (IEs) through the well‐known method of moments (MoM), thus leading to structured eigenvalue problems. These problems frequently become very large when solving complex arbitrary geometries with high accuracy. In such cases, the eigenvalue problem cannot be efficiently solved with standard methods by means of personal computers, essentially due to CPU time and memory allocation requirements. In this paper, we propose an alternative technique, based on the Lanczos method, for the fast and accurate solution of large BI‐RME generalized eigenvalue problems. The novel theoretical aspects of this approach, as well as the impacton the original BI‐RME formulation, are described. Comparative benchmarks are also successfully presented for the full‐wave analysis and design of real passive microwave devices. Copyright © 2005 John Wiley Sons, Ltd.     

复合保鲜剂对鲜切天麻贮藏品质的影响

目的通过探究复合保鲜剂对鲜切天麻保鲜效果的影响,为鲜切天麻采后保鲜提供参考依据。方法以鲜切天麻为实验材料,采用四因素三水平正交实验考察茶多酚、柠檬酸、抗坏血酸、壳聚糖复配对鲜切天麻感官评价的影响,以鲜切天麻感官评价为控制指标,筛选出适宜鲜切天麻的复合保鲜剂配方。结果复合保鲜剂的最佳配方为茶多酚质量分数1.25%,柠檬酸质量分数0.50%,抗坏血酸质量分数0.20%,壳聚糖质量分数0.90%。与采用清水处理相比较,该复合保鲜剂在4℃下贮藏15d,能有效维持鲜切天麻的硬度和色差L*值,延缓其天麻素和多糖含量的下降,保持鲜切天麻PPO活性和POD活性。结论复合保鲜剂能有效地保持鲜切天麻的商品价值,可用于鲜切天麻采后保鲜。     

基于几何结构的自适应空域错误隐藏算法

针对视频传输时容易发生损坏或丢失数据的问题,提出一种基于几何结构的自适应空域错误隐藏算法,以提高恢复图像质量。利用受损宏块的相邻2层像素提取几何结构,依据受损块相邻像素区分平滑块和边缘块。对平滑块采用双线插值,对边缘块根据内外两层的转折点寻找边缘方向,从而划分区域插值运算。实验结果表明,对于不同宏块丢失率和不同的视频序列,该算法所恢复的视频序列的峰值信噪比比双线插值、方向插值算法提高了0.5 dB~3 dB,不仅避免了虚假边缘,而且也提高了方向插值的准确性,改善了恢复图像的主观效果。     

浅谈发电企业一体化信息门户平台的建设

通过开发电厂企业信息门户及应用系统整合项目,叙述该项目启动的原因并提出方案。通过门户的建设．从信息资源分析和规划、应用集成和BI集成三个方面来将分散的应用、开发、安全、数据进行统一,建立企业一体化信息门户平台,使信息门户平台能够更好地解决信息化建设中各类资源的整合问题。     

基于Web服务的B2B电子商务的集成

介绍了Web服务及其关键技术,描述了如何应用Web服务技术实现电子商务各环节企业间无缝的整合,并通过具体实例讨论了如何利用Web服务实现各个企业间信息系统的无缝整合．     

牛膝中三萜皂苷类化合物的电喷雾电离串级质谱研究

采用大孔树脂柱层析分离方法分离提取牛膝 (Achyranthesbientata BI)中的三帖皂苷类化合物。通过相对分子质量及电喷雾电离多级串连质谱 (ESI-MSn)技术分别对牛膝提取物中的有效成分牛膝皂苷 (相对分子质量 95 6)、牛膝皂苷 (相对分子质量 794)进行定性分析 ,并提出了其电喷雾质谱碎裂机理。该方法样品处理简单 ,分析速度快且灵敏度高 ,适用作为牛膝有效成分三萜皂苷类物质鉴定的依据。     

基于Excel的OLAP的应用研究

针对目前OLAP在实际应用中存在的问题,本文引入了Excel分析软件,提出了一种基于Excel的OLAP。给出了一个完整的OLAP解决方案。这一方案将用户熟悉的Excel环境与OLAP技术完美结合起来,充分发挥用户分析数据的主动性。实际应用中的结果表明,提高了企业对现有的信息数据的利用效率,提高了企业决策分析的能力。     

Identification,characterisation and inhibition of Geotrichum pseudocandidum spoilage microbe in Gastrodia elata tuber

Gastrodia elata tuber is vulnerable to spoilage after harvested. A fungal strain Geotrichum pseudocandidum causing the spoilage was isolated from Gastrodia elata tuber and identified in this study. The log phase of the strain growth during incubation at 28 °C was from 24 to 48 h. The pH for highest spore production and largest colony formation were 5–6 and 7–9, respectively, while the temperature for them was 20–30 °C. Antifungal natamycin and tea polyphenols extract inhibited the stain at minimum inhibitory concentration of 0.25 and 0.5 mg mL⁻¹, respectively. A short-time heating treatment at temperature at 65 °C for 10 min also effectively prevented the strain growth. As tea extract is a GRAS (generally recognised as safe) food ingredient, the tea extract treatment could be a safe and non-thermal treatment to prevent the spoilage of Gastrodia elata tuber with less loss of heat-sensitive bioactives and other nutrients.