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排序方式: 共有2521条查询结果,搜索用时 31 毫秒
311.
Wan-Li He Meng-Die Yu Ya-Jie Pang Hao Ren Jun-Liang Ma Cheng Shi 《Liquid crystals》2019,46(2):249-256
A composite system of Fe3O4 nanoparticle-doped chiral nematic liquid crystals (N*LC) with flexible display performance was proposed. Fe3O4 nanoparticle and the nanoparticle-doped N*LC composite were detailed prepared and investigated. The influence of nanoparticle doping amount and chiral compound content on the magnetic performance as well as electrical performance of the flexible device had been studied in detail. The most suitable N*LC composites for magnetic-driven display had been found. With the characteristics of simple preparation, good stability and high resolution, the Fe3O4 nanoparticle-doped N*LCs had promising applications for power-free magnetic-driven flexible LC paper or display board. 相似文献
312.
Wei-Xiu Pang Hong-Ye Wu Jian-Jun Zhao 《Phosphorus, sulfur, and silicon and the related elements》2019,194(1-2):69-75
The anharmonic force field and spectroscopy constants for CH2PCl are determined using CCSD(T), VPT2, and density functional theory employing cc-pVQZ basis sets. The molecule structure, rotational spectroscopic constants, and vibrational wave numbers are compared with the available experimental data. Anharmonicity constants, vibration-rotation interaction constants and cubic force constants are predicted. Vibrational wave numbers and rotational constants for CD2PCl are also determined using the same levels. The isotopic shifts of vibrational wave numbers are remarkable by D atom substitution for 1-chlorophosphaethene. 相似文献
313.
Wang Ke Liu Ning Li Jun-qiang Wang Han Fu Xiao-long Li Huan Fan Xue-zhong Pang Wei-qiang 《Structural chemistry》2019,30(4):1233-1241
Structural Chemistry - Three 2,3-bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol tetranitrate (SMX)–based propellants were firstly reported, then the specific impulses of SMX-based propellants... 相似文献
314.
Jiaji Cheng Haodong Wang Xu Wang Shaoxiang Li Yue Zhou Feng Zhang Yong Wang Wenjuan Qu Dong Wang Xiujiang Pang 《先进技术聚合物》2019,30(12):3091-3098
Ramie fiber (RF) with excellent tensile strength was treated by a flame retardant and obtained the modified RF (MRF) that is incombustible. Then, MRF was used to improve the performance of rigid polyurethane foams (RPUF). The mechanical properties of the composite were investigated by compressive strength test and shear stress test. The fire characteristics were studied using a cone calorimeter. And the thermal decomposition and flammable properties were further evaluated using thermogravimetric analysis and limiting oxygen index. The results showed that MRF improve the mechanical properties of RPUF and eliminate the harm of flammability of RF on the RPUF. 相似文献
315.
Block M Bachelet C Bollen G Facina M Folden CM Guénaut C Kwiatkowski AA Morrissey DJ Pang GK Prinke A Ringle R Savory J Schury P Schwarz S 《Physical review letters》2008,100(13):132501
A new long-lived isomeric state in (65)Fe has been discovered with Penning trap mass spectrometry and high-precision mass measurements of the neutron-rich isotopes (63-65)Fe and (64-66)Co have been performed with the Low-Energy Beam and Ion Trap Facility at the NSCL. For the new isomer in (65)Fe an excitation energy of 402(5) keV has been determined from the measured mass difference between the isomeric and ground states. The mass uncertainties of all isotopes have been reduced by a factor of 10-100 compared to previous results. In the case of (64)Co the previous mass value was found to deviate by about 5 standard deviations from the new measurement. 相似文献
316.
LiCaBO3 was synthesized by high-temperature solid-state reaction. The influence of different rare earth dopants, i.e. Dy3+, Tb3+, Tm3+ and Ce3+, on thermoluminescence (TL) of LiCaBO3 phosphor was discussed. We studied the TL properties and some dosimetric characteristics of Ce3+-activated LiCaBO3 phosphor in detail. The effect of the concentration of Ce3+ on TL was investigated, the result of which showed that the optimum Ce3+ concentration was 1 mol%. The TL kinetic parameters of LiCaBO3:0.01Ce3+ were studied by computer glow curve deconvolution (CGCD) method. The three-dimensional (3D) TL emission spectra were also studied, peaking at 431 and 474 nm due to the characteristic transition of Ce3+. We also studied the linearity, annealing condition, reproducibility, fading and different heating rate of the LiCaBO3:0.01Ce3+ phosphor. 相似文献
317.
318.
依据Landau-Lifshitz阻尼项和Gilbert阻尼项的磁矩转动方程,提出统一形式的磁化率张量表达式.基于等效磁导率将非晶丝中各向异性的电磁场求解问题转化为等效的各向同性问题,进而分析了套在绝缘磁环或导电磁环中非晶丝的阻抗.采用基于有限元的数值方法仿真磁环中非晶丝的阻抗,仿真结果验证了理论分析结论.理论分析和仿真实验均表明,外磁体的附加阻抗将严重降低阻抗变化率,破坏巨磁阻抗特性.为此,提出采用回路形式降低附加阻抗的方法,并基于仿真实验验证了该方法的有效性.
关键词:
巨磁阻抗效应
非晶材料
Maxwell方程
有限元 相似文献
319.
An incremental bundle method for portfolio selection problem under second-order stochastic dominance
Numerical Algorithms - We propose a preconditioner to accelerate the convergence of the GMRES iterative method for solving the system of linear equations obtained from discretize-then-optimize... 相似文献
320.