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101.
Jianmei Liu Hong Wang Zhi Ma Qianheng Duan Yangyang Fei Xiangdong Meng 《Entropy (Basel, Switzerland)》2022,24(7)
In this paper, we consider the optimization of the quantum circuit for discrete logarithm of binary elliptic curves under a constrained connectivity, focusing on the resource expenditure and the optimal design for quantum operations such as the addition, binary shift, multiplication, squaring, inversion, and division included in the point addition on binary elliptic curves. Based on the space-efficient quantum Karatsuba multiplication, the number of CNOTs in the circuits of inversion and division has been reduced with the help of the Steiner tree problem reduction. The optimized size of the CNOTs is related to the minimum degree of the connected graph. 相似文献
102.
This paper investigates superconvergence properties of the local discontinuous Galerkin methods with generalized alternating fluxes for one-dimensional linear convection-diffusion equations. By the technique of constructing some special correction functions, we prove the(2k + 1)-th-order superconvergence for the cell averages, and the numerical traces in the discrete L~2 norm. In addition, superconvergence of orders k + 2 and k + 1 is obtained for the error and its derivative at generalized Radau points. All the theoretical findings are confirmed by numerical experiments. 相似文献
103.
WU Meng YANG Gui-zhong WANG Meng WANG Wei-zhi WANG Min LIU Tian-xi Key Laboratory of Molecular Engineering of Polymers of Ministry of Education 《高等学校化学研究》2008,24(5):653-657
Poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene](MEH-PPV)solutions with different concen-trations were prepared in chloroform for different ultrasonication times.The ultraviolet absorption and photoluminescence(PL)spectra of the MEH-PPV solutions were measured,and the electronic states of the polymer chains under different experimental conditions were studied.The results showed that the effects of ultrasonication on the dilute and concentrated solutions were different.After ultrasonication,the intensity of the absorption peak at 280 nm significantly decreased,relative to the absorption peak at 500 nm for both dilute and concentrated solutions,indicating that the proportion of the two excited states in the polymer chains had changed.For dilute MEH-PPV solutions,the blue-shifted absorption(at about 500 nm)and PL spectra show that ultrasonication also led to polymer chain degradation and thus shortened the effective conjugation length.For concentrated solutions,however,the peak positions of the absorption spectra remained unchanged.In addition,the effects of the solution temperatures on the optical spectra for the MEH-PPV solutions were also discussed. 相似文献
104.
Ali Diyapoglu Tao-Ho Chang Pi-Fang Linda Chang Jyh-Herng Yen Hsin-I Chiang Menghsiao Meng 《Molecules (Basel, Switzerland)》2022,27(15)
Plant-parasitic nematodes infect a diversity of crops, resulting in severe economic losses in agriculture. Microbial volatile organic compounds (VOCs) are potential agents to control plant-parasitic nematodes and other pests. In this study, VOCs emitted by a dozen bacterial strains were analyzed using solid-phase microextraction followed by gas chromatography–mass spectrometry. Fumigant toxicity of selected VOCs, including dimethyl disulfide (DMDS), 2-butanone, 2-pentanone, 2-nonanone, 2-undecanone, anisole, 2,5-dimethylfuran, glyoxylic acid, and S-methyl thioacetate (MTA) was then tested against Caenorhabditis elegans. DMDS and MTA exhibited much stronger fumigant toxicity than the others. Probit analysis suggested that the values of LC50 were 8.57 and 1.43 μg/cm3 air for DMDS and MTA, respectively. MTA also showed stronger fumigant toxicity than DMDS against the root-knot nematode Meloidogyne incognita, suggesting the application potential of MTA. 相似文献
105.
This paper researches the fixed-time leader-following consensus problem for nonlinear multi-agent systems (MASs) affected by unknown disturbances under the jointly connected graph. In order to achieve control goal, this paper designs a fixed-time consensus protocol, which can offset the unknown disturbances and the nonlinear item under the jointly connected graph, simultaneously. In this paper, the states of multiple followers can converge to the state of the leader within a fixed time regardless of the initial conditions rather than just converging to a small neighborhood near the leader state. Finally, a simulation example is given to illustrate the theoretical result. 相似文献
106.
107.
报道了一种宽温度适应范围的微型化人眼安全激光器。采用中心波长940 nm的二极管作为泵浦源,Er3+/Yb3+共掺磷酸盐玻璃作为增益介质,Co2+: MgAl2O4作为被动调Q晶体,研究了微型激光器的结构和激光在宽温度范围下的输出特性。当泵浦能量9 mJ,重复频率10 Hz,泵浦脉宽5 ms时,获得了单脉冲能量130 J,脉宽5.5 ns,峰值功率大于20 kW的激光输出,光束质量因子为1.3。采用真空封装工艺,在-40~50 ℃温度范围内,自然冷却方式下激光器稳定输出,功率不稳定性波动小于5%。 相似文献
108.
109.
阳庆国 黄显宾 刘冬兵 母健 但加坤 丰树平 谢旭东 邓武 叶雁 谭伯仲 卫兵 张思群 任晓东 欧阳凯 李勇 任济 丁渝 田青 王礼权 李恪宇 敬域堃 汪凌芳 余冰 王勐 彭其先 李泽仁 《强激光与粒子束》2016,28(04):040101
在聚龙一号脉冲功率装置上首次完成了对带正弦扰动铝套筒Z箍缩的X射线背光照相实验。实验采用千焦耳激光器(1053 nm, 1 kJ, 1 ns)驱动固体靶材产生X射线, 然后利用基于球面晶体的单色背光照相技术以及直接点投影背光照相技术, 成功观测到约7.5 MA电流驱动条件下, Z箍缩铝套筒的外边界不稳定性发展情况。该实验验证了在聚龙一号装置上联合千焦耳激光器开展X射线背光照相实验的能力, 为后续精密Z箍缩物理研究奠定了基础。 相似文献
110.
为了研究超高速碰撞产生闪光辐射的速度及角度效应, 利用建立的瞬态光纤高温计测量系统结合二级轻气炮加载系统, 进行了6种实验条件下的超高速碰撞实验。每组实验使用一组光纤探头, 基于实验所获原始数据结合标定, 通过Matlab编程处理得到了给定实验条件及光纤探头安装条件下, 超高速碰撞LY12铝靶产生的闪光辐射与碰撞速度和弹丸入射角度的关系。实验结果表明, 超高速碰撞LY12铝靶产生的闪光辐射在温度峰值出现前近似与碰撞速度和弹丸入射角度(弹道与靶板平面的夹角)正弦乘积的平方成正比;碰撞闪光辐射在温度峰值出现后近似与碰撞速度和弹丸入射角度正弦乘积的0.75次幂成正比, 与理论推导结果基本吻合。 相似文献