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为了深入研究中巴喀喇昆仑公路洪扎河以北地段的顺层岩质边坡弯曲失稳机制,采用材料力学压杆稳定及刚性体平衡原理,在D.S.Cavers的基础上考虑地震力作用,分析得到岩质边坡的三种弯曲模型(平面边坡的柔性弯曲、平面边坡的三铰梁模型、曲线边坡的三绞铰模型)的失稳公式,将地震与非地震作用下平面边坡的柔性弯曲进行对比分析。研究结果表明:当内摩擦角φj处于0°~15°范围时,若水平地震加速度方向与岩体弯曲方向相反,平面边坡柔性弯曲模型在地震作用下不易发生弯曲变形;若水平地震加速度方向与岩体弯曲方向一致,地震作用下平面边坡柔性弯曲模型的临界状态总长度l总比非地震作用下的l小,平面边坡在此方向的地震作用下更易发生柔性弯曲变形。 相似文献
995.
Muhammad Saqib Shahid Iqbal Asif Mahmood Raheel Akram 《International Journal of Food Properties》2016,19(4):745-751
The main objective of this research was to conduct a theoretical investigation into the antioxidant properties of chlorogenic acid. Calculations based on the density functional theory were performed using the B3LYP exchange-correlation functional and the 6-311G standard basis set to determine the theoretical parameters, such as bond dissociation enthalpy and spin density. H atom abstraction from ?OH groups was the most representative reaction pathway chosen for this study. From these calculations, it was estimated that bond dissociation enthalpies of hydroxyl groups were in the order of 3’-OH > 4’-OH > 2-OH > 1-OH. Spin densities of O-atoms of free radicals formed (after the removal of H atoms) from the hydroxyl groups of aromatic rings were lower than that of hydroxyl groups of alicyclic rings. On the basis of the calculated results, H atom abstraction from ?OH groups of aromatic ring should be the main mechanism for the antioxidant potential of chlorogenic acid. Moreover, a comparison of bond dissociation enthalpy values for different phenolic acid antioxidants showed that the chlorogenic acid is a potent antioxidant. This theoretical investigation might be helpful for the future applications of chlorogenic acid in the field of the pharmacy and food industries. 相似文献
996.
Syed M. Nasar‐Abbas Zill‐ e‐Huma Thi‐Huong Vu Muhammad Kamran Khan Henry Esbenshade Vijay Jayasena 《Comprehensive Reviews in Food Science and Food Safety》2016,15(1):63-72
Carob (Ceratonia siliqua L.) is well known for its valuable locust bean gum obtained from the carob seeds. Separation of seeds from the pod leaves behind the carob kibble which is a good source of dietary fiber, sugars, and a range of bioactive compounds such as polyphenols and pinitol. Bioactive compounds present in carob kibble have been found to be beneficial in the control of many health problems such as diabetes, heart diseases, and colon cancer due to their antidiabetic, antioxidant, and anti‐inflammatory activities. Carob kibble has substantial potential to be used as a food ingredient. This article focuses on the composition, health benefits, and food applications of carob kibble. 相似文献
997.
In nature, objects have partially weak texture and their shape reconstruction using focus based passive methods like shape from focus (SFF), is difficult. This article presents a new SFF algorithm which can compute precise depth of dense as well as weak textured objects. Segmentation is applied to discard wrong depth estimate and then later interpolating them from accurate depth values of their neighbors. The performance of the proposed method is tested, using different image sequences of synthetic and real objects, with varying textures. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc. 相似文献
998.
Nasir Abbas Muhammad Riaz Ronald J. M. M. Does 《Quality and Reliability Engineering International》2013,29(5):653-663
Control charts are the most extensively used technique to detect the presence of special cause variations in processes. They can be classified into memory and memoryless control charts. Cumulative sum and exponentially weighted moving average control charts are memory‐type control charts as their control structures are developed in such a way that the past information is not ignored as it is done in the case of memoryless control charts, like the Shewhart‐type control charts. The present study is based on the proposal of a new memory‐type control chart for process dispersion. This chart is named as CS‐EWMA chart as its plotting statistic is based on a cumulative sum of the exponentially weighted moving averages. Comparisons with other memory charts used to monitor the process dispersion are done by means of the average run length. An illustration of the proposed technique is done by applying the CS‐EWMA chart on a simulated dataset. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
999.
Asep Suhendi Muhammad Miftahul Munir Adi Bagus Suryamas Asep Bayu Dani Nandiyanto Takashi Ogi Kikuo Okuyama 《Advanced Powder Technology》2013,24(2):532-536
A new electrospray system has been successfully developed by employing a proportional–integral–derivative control action to maintain an electric current at a certain value. A polymer precursor solution containing polyethylene glycol was used to examine the performance of this system. The result showed that cone-jet geometry could be controlled easily by adjusting the electric current. The length of the cone-jet decreased as the electric current was increased, in a correlation that followed power law. We also found that the cone-jet observed during electrospraying was stable and robust with no disturbance during long periods of use (up to 4000 s). The present study is very useful for further development of high precision aerosol generators and particle synthesis. 相似文献
1000.
We derive analytic expressions for the polarization characteristics of light emerging from a magneto-optical medium possessing arbitrary contributions from linear and circular birefringence as well as magnetic circular dichroism. The medium is placed inside a static magnetic field. The rotation of the plane of polarization and the ellipticity of the resultant light exhibit interesting characteristics that can be a useful guide in the design and analysis of new photonic devices. Furthermore, the Jones matrices are derived in all cases, including for elliptical dichroism, indicating the role of hyperbolic trigonometric functions in modeling the effects of dichroism. Finally, implications for experimental detection of the polarization state and the limits on the performance of optical isolators are discussed. 相似文献