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1.
In this study, a fingerprint-activity relationship modeling between chemical fingerprints and antirheumatic activity was established, and multivariate statistical analysis was used to evaluate the quality of Taxilli Herba (TH) from different hosts. Characteristic fingerprints of 20 batches of TH samples were generated by high-performance liquid chromatography coupled with triple quadrupole-time of flight tandem mass spectrometry (HPLC-Triple TOF-MS/MS), and the similarity analysis was calculated based on thirteen common characteristic peaks by hierarchical clustering analysis (HCA). Subsequently, nine efficacy markers were discovered by combining fingerprints and antirheumatic activity through grey correlation analysis (GCA) and bivariate correlation analysis (BCA). Meanwhile, the content of 5 constituents in 9 markers was determined by high-performance liquid chromatography coupled with triple quadrupole-linear ion trap tandem mass spectrometry (HPLC-QTRAP-MS/MS). The comprehensive quality of TH was assessed using multivariate statistical analysis, including principal components analysis (PCA) and technique for order preference by similarity to ideal solution (TOPSIS). The results showed that a high dose of TH extract could markedly ameliorate arthritis damage compared to other doses, with flavonoids playing an important role in the antirheumatic activity. The comprehensive quality of samples from Morus alba L. (SS) was superior to those from Liquidambar formosana Hance (FXS). The present study will demonstrate the markers associated with efficacy, and provide an applicable strategy for more comprehensive quality control and evaluation of TH.  相似文献   
2.
The cable net supported glass curtain wallas the most advanced technique in dot point supported glass curtain wall, is widely used in China. Because of its large deflection and high nonlinearity under wind load, the dynamic performance of the cable net is greatly different from that of the conventional linear structures. The continuous membrane theory is used to construct the nonlinear vibration differential equation of the cable net, and the harmonic balance method is used to solve the analytic formula of the nonlinear frequency. In order to verify the accuracy of the above analytic formula, the results of the formula and the nonlinear FEM time-history method are compared and found to be in good agreement. Furthermore, the nonlinear vibration differential equation and the nonlinear frequency obtained in this paper are the basis for the wind-induced response analysis of a cable net under fluctuating wind load.  相似文献   
3.
李承跃  J.P.Allain  邓柏权 《中国物理》2007,16(11):3312-3318
This paper explores the effect of a liquid lithium curtain on fusion reactor plasma, such curtain is utilized as the first wall for the engineering outline design of the Fusion Experimental Breeder (FEB-E). The relationships between the surface temperature of a liquid lithium curtain and the effective plasma charge, fuel dilution and fusion power production have been derived. Results indicate that under normal operation, the evaporation of liquid lithium does not seriously affect the effective plasma charge, but effects on fuel dilution and fusion power are more sensitive. As an example, it has investigated the relationships between the liquid lithium curtain flow velocity and the rise of surface temperature based on operation scenario II of the FEB-E design with reversed shear configuration and high power density. Results show that even if the liquid lithium curtain flow velocity is as low as 0.5 m/s, the effects of evaporation from the liquid lithium curtain on plasma are negligible. In the present design, the sputtering of liquid lithium curtain and the particle removal effects of the divertor are not yet considered in detail. Further studies are in progress, and in this work implication of lithium erosion and divertor physics on fusion reactor operation are discussed.[第一段]  相似文献   
4.
伴有热污染的气幕上吸罩流场特性分析   总被引:1,自引:0,他引:1  
传统排风罩和气幕上吸罩是两种工作原理不同的局部排风设备。建立了气幕上吸罩流场模型并确定了边界条件,采用数值计算的方法,模拟了气幕上吸罩速度场和温度场。提出把控制点(面)速度作为评价流场控制能力强弱的一个参数,并依此定量比较了传统上吸罩和气幕上吸罩的控制效果。结果表明:送风射流装置可以把热污染气流控制在较小的范围内;在模拟实验条件下,在控制点达到相同的控制风速时,气幕式上吸罩所需吸气量为传统吸气罩吸气量的77%~86%。  相似文献   
5.
反应器内液滴粘壁对半干法烟气脱硫效率和运行稳定性具有重要影响.本文采用数值方法研究了不同贴壁风风速和风口高度对反应器内液滴粘壁现象的影响规律.结果表明,贴壁风对减轻液滴粘壁具有一定作用.贴壁风风速越高,液滴贴壁数量越少.贴壁风衰减较快,其风口高度存在最佳值,贴壁风风口与液滴喷射口的高度距离是按照液滴直线运动粘壁时液滴高度行程的1.2倍.  相似文献   
6.
An experimental and numerical analysis of the interaction between a plane horizontal water flow in a rectangular channel (free water current) and a plane thin water jet (water jet curtain) is presented; the jet flows out vertically from either a slot nozzle in the bottom of the channel or the crest of a rigid spillway at a velocity appreciably (several times) greater than the water velocity in the channel. Numerical calculations were carried out using the STAR-CD software package preliminarily tested against the experimental data obtained. The dependence of the water level in the channel at a certain distance ahead of the jet barrier on the main jet parameters and the water flow rate in the horizontal channel is studied. It is found that in the region of the interface between the flows both steady and unsteady (self-oscillatory) flow patterns can be realized. Steady stream/jet interaction patterns of the “ejection” and “ejection-spillway” types are distinguished and a criterion separating these regimes is obtained. The notion of a rigid spillway equivalent to a jet curtain is introduced and an approximate dependence of its height on the relevant parameters of the problem is derived. The possibility of effectively controlling the water level ahead of a rigid spillway with a sharp edge by means of a plane water jet flowing from its crest is investigated. The boundary of transition to self-oscillation interaction patterns in the region of the flow interface is determined. The structure of these flows and a possible mechanism of their generation are described. Within the framework of the inviscid incompressible fluid model in the approximate formulation for a “thin” jet, an analytical dependence of the greatest possible depth of a reservoir filled with a heavy fluid at rest and screened by a vertical jet barrier on the jet parameters is obtained.  相似文献   
7.
新型单帘航摄焦平面快门   总被引:1,自引:1,他引:1  
快门是控制感光介质曝光量的重要组件,为使航摄快门适应面阵CCD相机对空间结构上的要求,同时做到幅面曝光时间均匀、曝光时间调节范围大、并且曝光时间连续可调,设计了新型帘幕式快门。在分析了快门的曝光原理的基础上推导出快门有效曝光时间计算公式,并结合快门的有效曝光时间计算公式设计了单帘式快门,采用帘幕环绕面阵CCD的快门结构形式,快门帘幕采用四辊轴的结构形式,并利用正时带实现了快门的曝光功能,利用高斯误差合成对快门系统的精度进行了分析计算,得到系统的曝光精度为0.057。实验结果显示,快门能够实现1/50~1/250 s的曝光时间调节范围,通过光电法实验测得快门的曝光精度达到0.056,满足0.1的曝光精度指标要求。  相似文献   
8.
研制了一个改进的激波管设备,对马赫数为1.2的弱激波冲击作用下空气中SF6气柱和气帘界面的演变过程进行了初步的实验研究。通过设计激波管实验段、烟雾发生器、气体箱、进气吸气系统和激波管尾段,控制混合气体中SF6的峰值浓度和初始气流速度,建立了稳定、可重复的无膜气柱和气帘初始界面形成技术。利用高速摄影技术,在水平面内观测了气柱和气帘的初始界面图像,沿垂直方向观测了界面RM(Richtmyer-Meshkov)不稳定性的演变过程。气柱演变图像显示了典型的对涡结构,气帘演变图像显示了早期的多蘑菇形结构和后期的相邻波长干扰效应。图像后处理表明,气柱的高度和宽度、气帘的宽度均随时间单调增加,且宽度比高度增加快得多。从二维涡量动力学方程出发,对图像中涡的演变过程进行了初步解释。  相似文献   
9.
在分析热对流、传导和辐射等热力学传导要素的基础上,介绍了中空玻璃、真空玻璃、吸热玻璃、热反射镀膜玻璃、低辐射镀膜玻璃、智能幕墙层等的节能效果,最后给出了玻璃幕墙上窗的结构形式及选材.  相似文献   
10.
为解决玻璃幕墙人工清洗工作量大,危险性高的问题,设计了这一玻璃幕墙清洗机器人。系统以STC12C5A60S2单片机为主控制器,通过控制42HS4817A4型号步进电机带动微型直线滑台,实现机器人玻璃面上下机械运动,最大运行速度约60mm/s,采用12V减速直流电机,5V马达,20ml量程注射器,PJYS40-15-N型号真空吸盘的组合,实现机器人脚吸附和脱离玻璃面,多次试验,稳定吸附结果高达95%以上。采用PT2262和PT2272无线发射接收器,实现无线遥控操作。试验结果表明,该系统制作成本低, 轻量化设计灵活性好,具有一定的实用价值。  相似文献   
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