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981.
982.
Guizhong Xie Jianming ZhangYunqiao Dong Cheng HuangGuangyao Li 《International Journal of Solids and Structures》2014
This paper presents an improved exponential transformation for nearly singular boundary element integrals in elasticity problems. The new transformation is less sensitive to the position of the projection point compared with the original transformation. In our work, the conventional distance function is modified into a new form in the polar coordinate system. Based on the refined distance function, an improved exponential transformation is proposed in the polar coordinate system. Moreover, to perform integrations on irregular elements, an adaptive integration scheme considering both the element shape and the projection point associated with the improved transformation is proposed. Furthermore, when the projection point is located outside the integration element, another nearest point is introduced to subdivide the integration elements into triangular or quadrilateral patches of fine shapes. Numerical examples are presented to verify the proposed method. Results demonstrate the accuracy and efficiency of our method. 相似文献
983.
984.
当前,由于软件发行商通常不为应用程序和可执行文件(程序文件,共享库,脚本等)提供用以验证其可靠性的关键信息,所以计算机管理员想要自动辨别这些文件是否被第三方修改过变得十分困难.通过与民航飞行的安全性要求进行类比,分析了软件身份标签如何从身份鉴别、应用关联、防止篡改和未知威胁这四方面改善软件的安全性. 相似文献
985.
Ting Zhi Tao Tao Xiaoyan Liu Junjun Xue Jin Wang Zhikuo Tao Yi Li Zili Xie Bin Liu 《半导体学报》2021,42(12):57-61
Plasmonic nanolaser as a new type of ultra-small laser,has gain wide interests due to its breaking diffraction limit of light and fast carrier dynamics characters.Normally,the main problem that need to be solved for plasmonic nanolaser is high loss induced by optical and ohmic losses,which leads to the low quality factor.In this work,InGaN/GaN nanoplate plasmonic nanolaser with large interface area were designed and fabricated,where the overlap between SPs and excitons can be en-hanced.The lasing threshold is calculated to be ~6.36 kW/cm2,where the full width at half maximum (FWHM) drops from 27 to 4 nm.And the fast decay time at 502 nm (sharp peak of stimulated lasing) is estimated to be 0.42 ns.Enhanced lasing charac-ters are mainly attributed to the strong confinement of electromagnetic wave in the low refractive index material,which im-prove the near field coupling between SPs and excitons.Such plasmonic laser should be useful in data storage applications,bio-logical application,light communication,especially for optoelectronic devices integrated into a system on a chip. 相似文献
986.
Dimitrios Pavlidis Jefferson L. M. A. Gomes Zhihua Xie James R. Percival Christopher C. Pain Omar K. Matar 《国际流体数值方法杂志》2016,80(4):256-282
This paper develops methods for interface‐capturing in multiphase flows. The main novelties of these methods are as follows: (a) multi‐component modelling that embeds interface structures into the continuity equation; (b) a new family of triangle/tetrahedron finite elements, in particular, the P1DG‐P2(linear discontinuous between elements velocity and quadratic continuous pressure); (c) an interface‐capturing scheme based on compressive control volume advection methods and high‐order finite element interpolation methods; (d) a time stepping method that allows use of relatively large time step sizes; and (e) application of anisotropic mesh adaptivity to focus the numerical resolution around the interfaces and other areas of important dynamics. This modelling approach is applied to a series of pure advection problems with interfaces as well as to the simulation of the standard computational fluid dynamics benchmark test cases of a collapsing water column under gravitational forces (in two and three dimensions) and sloshing water in a tank. Two more test cases are undertaken in order to demonstrate the many‐material and compressibility modelling capabilities of the approach. Numerical simulations are performed on coarse unstructured meshes to demonstrate the potential of the methods described here to capture complex dynamics in multiphase flows. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
987.
Enzymatic Synthesis of Acylphloroglucinol 3‐C‐Glucosides from 2‐O‐Glucosides using a C‐Glycosyltransferase from Mangifera indica
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Dawei Chen Lili Sun Dr. Ridao Chen Dr. Kebo Xie Prof. Dr. Lin Yang Prof. Dr. Jungui Dai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):5873-5877
A green and cost‐effective process for the convenient synthesis of acylphloroglucinol 3‐C‐glucosides from 2‐O‐glucosides was exploited using a novel C‐glycosyltransferase (MiCGTb) from Mangifera indica. Compared with previously characterized CGTs, MiCGTb exhibited unique de‐O‐glucosylation promiscuity and high regioselectivity toward structurally diverse 2‐O‐glucosides of acylphloroglucinol and achieved high yields of C‐glucosides even with a catalytic amount of uridine 5′‐diphosphate (UDP). These findings demonstrate for the first time the significant potential of a single‐enzyme approach to the synthesis of bioactive C‐glucosides from both natural and unnatural acylphloroglucinol 2‐O‐glucosides. 相似文献
988.
New designed DNA light switch Ruthenium complexes as DNA photocleavers and Topoisomerase I inhibitors
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Xue‐Wen Liu Yang Xiao Wei‐Gen Peng Li‐Jin Zhao You‐Ming Shen Song‐Bai Zhang Ji‐Lin Lu 《应用有机金属化学》2018,32(4)
Two ruthenium complexes containing a new ligand phipz (phipz = 2‐(1,10‐phenanthroline)‐1H‐imidazo[4,5‐b]phenazine) were designed and synthesized. These complexes were found to inhibit the DNA supercoiled relaxation mediated by topoisomerase I (topo I), cleave DNA under irradiation and bind to calf thymus DNA through intercalative mode. Furthermore, complex 2 shows higher photocleavage activity, topo I inhibition activity and DNA affinity than complex 1 . Additionally, introduction of phenazine unit may be the reason that two complexes exhibit DNA ‘light switch’ behavior. The present work shows that two complexes might be potential as new DNA ‘light switches’, DNA photocleavers and topo I inhibitors. 相似文献
989.
Two new Zn2Dy2 complexes were constructed from Zn (II) salen‐type Schiff base complex fragment and 2,6‐pyridinedimethanol (H2pdm) or its Br‐substituted analogue (4‐bromopyridine‐2,6‐diyl)dimethanol (H2Brpdm); their molecular formulas are [Zn2Dy2(L)2(pdm)2(MeOH)2](ClO4)2 [ 1 , H2L = N, N′‐ bis(3‐methoxysalicylidene)‐1,3‐diaminopropane] and [Zn2Dy2(L)2(Brpdm)2(MeOH)2](ClO4)2 [ 2 ], the Dy (III) ions of which have a NO7 triangular dodecahedral coordination sphere. The two complexes show not only ferromagnetic interaction but also field‐induced single‐molecule magnet (SMM) behavior, which are rare Dy (III)‐containing cluster complexes with the NO7 triangular dodecahedral coordination sphere that can show good magnetic relaxation. The energy barrier value of complex 2 is higher than those of complex 1 and the Dy (III) complexes with the DyNO7 triangular dodecahedral coordination configuration reported in the literature. 相似文献
990.
Weihua Zhou Zoukangning Yu Ming Zhang Lifu Zhang Jingping Yin Qingyun Ai Liqiang Huang Feng Liu Jianrong Zeng Yiwang Chen 《Journal of Polymer Science.Polymer Physics》2019,57(14):941-951
In order to explore the role of fluorine atoms on photostability as well as morphology control of active layer in the presence of 1,4‐butanedithiol (BT), the four polymers with or without fluorine atoms in the backbones including polythieno[3,4‐b]thiophene/benzodithiophene, poly[(4,8‐bis‐(2‐ethylhexyloxy)‐benzo(1,2‐b:4,5‐b9)dithiophene)‐2,6‐diyl‐alt‐(4‐(2‐ethylhexanoyl)‐thieno[3,4‐b]thiophene‐)‐2‐6‐diyl)], poly[4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b;4,5‐b′]dithiophene‐2,6‐diyl‐alt‐(4‐(2‐ethylhexyl)‐3‐fluorothieno[3,4‐b]thiophene‐)‐2‐carboxylate‐2‐6‐diyl)], and poly[4,8‐bis‐(2‐ethyl‐hexyl‐thiophene‐5‐yl)‐benzo[1,2‐b:4,5‐b0]dithiophene‐2,6‐diyl]‐alt‐[2‐(20‐ethyl‐hexanoyl)‐thieno [3,4‐b]thiophen‐4,6‐diyl] were selected for comparison. It is found that the specimens containing fluorine atoms in polymer backbones showed of higher stability after illumination for 1 h in the presence of BT additive, contributing to the higher domain purity. The specific interaction between fluorine atoms and thiol groups was demonstrated by the appearance of novel absorption peak at 2663.1 cm?1, in addition to the broadening of peak at 2556.2 cm?1 ascribing to S? H stretching vibration as confirmed by Fourier transform infrared (FTIR) spectroscopy. The finding may guide the accurate use of thiols as effective solvent additive in morphology and stability optimization. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 941–951 相似文献