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71.
The minimal dilaton model(MDM) extends the Standard Model by one singlet scalar called dilaton and one top quark partner called t. In this work we investigate the t-induced radiative correction to the Higgs-strahlung production process e+e-→ Zh at future Higgs factory. We first present the analytical calculations in detail and show how to handle the ultraviolet divergence. Then we calculate the correction numerically by considering the constraints from precision electroweak data. We find that, for sin θL= 0.2 and mt = 1200 Ge V, the correction is 0.26% and 2.1% for (se+e)~(1/2)-= 240 Ge V, 1 Te V respectively, and a larger value can be achieved as sin θLincreases.  相似文献   
72.
We investigate the one-loop contributions to the mass of the SM-like Higgs boson in the MSSM considering the effect of slepton flavor mixing, which is parametrized by the dimensionless parameter δXY (X,Y=L,R) in the slepton mass matrices. For the surviving samples under the experimental constraints, we calculate the corrections to the mass of the SM-like Higgs boson in terms of δXY. We find that the mass correction Δmh can even be larger than 10 GeV for large δRL or δLR. Moreover, Δmh has strong sensitivity to δRL or δLR, while the weak sensitivity to δLL or δRR, since δRL or δLR enters directly into the coupling of Higgs boson with sleptons in the calculations of Higgs boson self-energies.  相似文献   
73.
研究了环境相对湿度、 温度、 溶液浓度、 纺丝电压和接收距离对聚甲醛(POM)电纺纤维表面孔形貌的影响. 结果表明, 空气中一定含量的水对孔的形成至关重要; 纺丝液浓度对孔的大小有影响. 并对POM 纤维表面成孔的可能机理进行了分析.  相似文献   
74.
Three FeIII2LnIII2 tetranuclear heterometallic clusters, [H4LGd(H2O)Tp*Fe(CN)3]2·8H2O·2MeOH (1) and [H4LLn(MeOH)Tp*Fe(CN)3]2·6MeOH·2MeCN (Ln?=?Tb and Dy for 2 and 3, respectively, H6L = N,N′-(2,6-pyridine-dicarboxyl)-disalicylhydrazide, Tp* = hydridotris(3,5dimethylpyrazol-1-yl)-borate), were synthesized by use of the [(Tp*)Fe(CN)3]? unit as a metalloligand toward LnCl3 and H6L species. Structural analyses reveal that FeIII and LnIII ions in all complexes are connected to each other by one cyanide to form a heterobinuclear unit of [Ln(H4L)][(Tp*)Fe(CN)3], which is dimerized through Ln–N–C?=?O–Ln interaction. Magnetic susceptibility measurements show weak antiferromagnetic interactions between cyano-bridged FeIII and GdIII ions and amide-bridged GdIII ions are operative. Complex 1 displays the magnetocaloric effect with ?ΔSmmax = 12.70 J·kg?1·K?1 at 4.0 K for ΔH?=?7 T. No single-molecule magnetic properties are observed for 2 or 3 down to 1.8 K.  相似文献   
75.
Considering that capillary force is one of the most important forces between nanoparticles and atomic force microscope (AFM) tips in ambient atmosphere, we develop an analytic approach on the capillary force between an AFM tip and a nanoparticle. The results show that the capillary forces are considerably affected by the geometry of the AFM tip, the humidity of the environment, the vertical distance between the AFM tip and the nanoparticle, as well as the contact angles of the meniscus with an AFM tip and a nanoparticle. It is found that the sharper the AFM tip, the smaller the capillary force. The analyses and results are expected to be helpful for the quantitative imaging and manipulating of nanoparticles by AFMs.  相似文献   
76.
利用多元散射校正提高油菜籽脂肪酸近红外分析精度   总被引:4,自引:0,他引:4  
近红外光谱技术可对完整油菜籽进行快速无损检测分析,但因受样品装填密度、颗粒大小及分布不均匀等物理因素的影响,光谱测量散射误差较大.本文利用MSC技术、相关分析和微分预处理光谱数据,结合PLS回归建模和交叉验证方法,建立了油菜籽脂肪酸近红外光谱分析模型.研究表明,MSC校正和其它光谱预处理方法相结合显著地提高了模型的分析精度,减少了模型的PLS主因子数.  相似文献   
77.
A novel dinuclear copper(Ⅱ) complex [CuL(NO3)]2·2MeOH was obtained by the coordination reaction of Cu(NO3)2·3H2O with ligand HL (HL=N-(methyl-2-benzimidazol- methylidene)-2-hydroxyaniline). The single-crystal X-ray analysis has revealed that the complex crystallizes in triclinic, space group P with a=9.535(3), b=10.009(3), c=10.666(4) , α=104.303(4), β=100.105(4), γ=115.917(4)o, V=839.0(5) 3, C16H16CuN4O5, Mr=407.87, Z=2, Dc=1.614 g/cm3, F(000)=418, μ=1.338 mm-1, R=0.0543 and wR=0.0980. The basic dinuclear copper(Ⅱ) complex units [CuL(NO3)]2 are formed by NO3- as co-bridging ligands and L as NNO tridentate chelate coordinating to the copper ions. The ladder-like one-dimensional chain motifs are formed by O…H-O and O…H-N hydrogen bonds from methanol molecules connecting the dinuclear copper(Ⅱ) units.  相似文献   
78.
孟丽娜  张明江  郑建宇  张朝霞  王云才 《物理学报》2011,60(12):124212-124212
利用外部光注入混沌激光器产生了完全符合美国联邦通信委员会关于室内无线通信频谱限定的超宽带(UWB)微波信号.基于外部光注入光反馈半导体激光器的速率方程组,理论研究了外部及内部参量对半导体激光器输出混沌UWB脉冲信号的影响.研究表明,UWB信号的-10 dB带宽随着光注入强度、注入失谐量以及线宽增强因子的增大而增大,随着激光器偏置电流的增大而减小.同时,UWB信号的中心频率在5–8 GHz范围内变化.在实验中,通过设定其他参量和调节光注入强度,得到中心频率及带宽可调谐的混沌UWB微波信号,传输速率达到500 Mbit/s.实验结果与理论分析相符合. 关键词: 半导体激光器 混沌激光 光生微波技术 超宽带信号  相似文献   
79.
本文报道了两条温和、高效、实用的实验室合成对氯代醌基碳糖苷化合物的方法:其一是以芳香碳糖苷1a (1b)为初始原料,在硝酸铵催化下,与N-氯代丁二酰亚胺(NCS)反应获得对氯代芳香碳苷2a (2b),继而经硝酸铈铵(CAN)氧化,得到氯代醌基糖苷3a (3b),总收率为88% (84%);另一路线是通过三甲基氯硅烷在三氟化硼•乙醚作用下对苯醌碳苷4a (4b)的催化加成和水解反应,获得对氯代氢醌基碳苷5a (5b),总收率为82% (76%), 而它与氯代醌基糖苷3a (3b)可以通过氧化与还原反应得以相互转化。  相似文献   
80.
In this paper, a new theoretical model for Rayleigh backscattering (RB) analysis of fiber Raman amplifiers is proposed. The model includes all the interactions among the pumps, signals, and all orders of RB. The results show that the higher order RB has a negligible influence on the performance of the amplifier. The co-propagating and counterpropagating RB power of the signal grow quadratically with the net-gain of the amplifier. The signal to double Rayleigh backscattering noise ratio (OSNRDRB ) of backward-pumped FRAs is better than that of the forward-pumped ones at high net-gain level (> 13 dB), while at low net-gain level the OSNRDrb of the forward-pumped FRAs is slightly better than that of the backward-pumped ones.  相似文献   
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