超声波辅助提取竹叶黄酮的研究

以青竹叶为原料、乙醇为萃取剂,利用超声波辅助提取其中的黄酮类物质。研究了溶剂浓度、料液比、搅拌速度、超声波功率、萃取时间、萃取次数等因素对产物得率的影响。结果表明:常温下,乙醇浓度为75%,料液比为1∶15(g/mL),搅拌速度为80r/min,超声功率为30 W,单次萃取时间为25 min,萃取3次,黄酮提取率最高为2.91%。与常规提取方法相比,超声波法具有省时节能、提取率高等优势。对油脂氧化抑制作用研究表明,竹叶黄酮具有良好的抗氧化性,可以作为天然绿色的抗氧剂进行开发。     

病虫害防治新探索

通过对化学方法进行病虫害防治可导致环境及人类为害的分析,提出了利用物理学中共振原理进行病虫害防治的新思路,探讨了其应用前景。     

Application of Pushover Method to Seismic Performance Evaluation of Tall Piers for Bridge

For bridge with tall piers, the influence of higher modes on structural responses becomes more evident. Modified MPA method(MMPA) which is based on MPA theory and the concept of “equivalent mode height” is presented. To verify the effectiveness and the degree of accuracy of this method, several Pushover methods including MPA and MMPA methods were adopted to analyze tall piers for bridge, and then compares the results with that in dynamic time-history analysis. It is shown that MPA and MMPA methods can improve computational accuracy comparing with other normal Pushover methods when seismic intensity is lower, whereas the computational accuracy for MMPA methods is superior to that in MPA analysis with the seismic intensity becoming larger.     

Comparison Analysis of Calculation Methods of Seismic Displacement for the Isolation System Based on Pure Rolling

With the isolation system based on pure rolling as the object of study, the computer program was develeped to calculate its seismic displacement based on its characteristics. And then, experiment method and theory analysis method were adopted to analyze the new computer program and the traditional calculation method’s rationality in contrast. It is shown that the computer program is reasonable, and its results are relatively accurate and conservative. The traditional calculation method based on the rigid-plastic relation of force and displacement is illogical, and its results are relatively small. When subjected to earthquakes, the structures maximum relative displacement would be larger than the earths maximum absolute displacement.     

QRS complexes detection using quadratic b-spline wavelet transform algorithm

Aiming at the low accuracy and low adaptability of wave detection, a QRS complexes detection algorithm is proposed based on quadratic b-spline wavelet, while combined with binary search algorithm and arc approximating curve algorithm. The signal is decomposed with quadratic b-spline wavelet through Mallat algorithm and the R wave is detected by adjusting the threshold with binary search and modulus maximumizing. The T wave and P wave are detected by using arc approximating curve algorithm based on the least square. This algorithm is certified with the ECG signals from MIT-BIH database and is demonstrated that the algorithm enhanced the adaptability of R wave detection and improved the accuracy of T wave and P wave detection. The simulation experiment shows that the improved algorithm can effectively improve the automatic detection capabilities of ECG signals.     

带有次线性可乘白噪音的广义波方程的随机吸引子

说明带有次线性可乘白噪音扰动的广义波方程的解生成随机动力系统,证明了此随机动力系统存在吸收所有有界集的紧随机集,且此随机动力系统存在全局吸引子.     

淫羊藿总黄酮提取方法的比较研究

为了比较不同提取方法对中药淫羊藿总黄酮含量的影响,试验采用水煎、超声波和回流法进行总黄酮的提取,采用紫外分光光度法测定其含量。结果表明:回流组和超声3组总黄酮含量极显著高于超声2组、超声1组和水煎组(P<0.01),超声2组总黄酮含量极显著高于超声1组和水煎组(P<0.01),超声1组总黄酮含量极显著高于水煎组(P<0.01)。说明采用回流法(用80%乙醇回流)提取淫羊藿总黄酮的提取率最高,水煎法提取率最低。     

地质构造对汶川大地震山地灾害发育的影响

通过对汶川大地震灾区的调查和遥感解译,在GIS平台上对4945个灾害点进行统计,分析了山地灾害与地震烈度、距中央断裂带距离、岩性等地质构造因素的关系,研究了地震条件下地质构造对山地灾害发育的影响。结果表明:(1)地震能量主要沿中央断裂带释放,在短轴方向上能量衰减很快,灾害密度在距中央断裂0～12km范围内较大,然后锐减,灾害点呈条带状分布与中央断裂走向一致。中央断裂带逆冲走滑造成其上盘灾害发育明显高于下盘,而前山断裂带逆冲走滑与中央断裂的影响叠加造成中央断裂下盘灾害发育密度呈先降低后升高再降低的变化特点。(2)灾害总数的99.29%集中分布在地震烈度Ⅶ度及其以上地区,中央断裂带两侧高地震烈度的Ⅺ和Ⅹ区灾害不仅数量多,密度大,而且灾害规模也大,反映地震能量在形成灾害方面具有重要作用。(3)灾害密度顺序为:硬岩岩层偶滑岩层易滑岩层较易滑岩层,当软硬岩层相间时,特别是硬岩在上时,在地震波的作用下容易发生开裂、崩塌和滑坡,且分别在硬质岩层和软弱岩层中较为发育。     

利用脉搏波参数间接测定大鼠动脉血压的一种方法

通过提取动脉脉搏波特征参数,建立了间接测定大鼠动脉血压的多元回归方程。结果表明:脉搏波周期、K值、脉搏波波图面积等参数与动脉收缩压有较好的相关性,与颈动脉有创血压测定法数值比较,有较小差异(P>0. 05),表明所筛选的脉搏波特征参数能准确地反映动脉的每搏收缩压值,但与舒张压相关性较差。该方法简便、准确、稳定性好,便于长期动态观察。     

水中爆破对海洋生物及海洋环境的影响研究

本文主要根据１９８３年６月在莱州湾现场模拟水中爆破勘探石油对水产资源的影响实验，分别实验了爆破所产生的声压波对鱼、虾、蟹、贝类和浮游生物的影响，采集并分析了爆炸前后的海水样品。由实验结果得出，水中爆破对海水水质的影响主要因素是：悬浮物、无机氮等。水中爆破所产生的声压波对海洋生物有一定的致死作用，但致死范围不大，而对水产资源的幼体和浮游生物伤害较大。