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111.
基于Z-Tree实验平台利用研发投资自然博弈实验研究发现风险规避导致女性的研发投入强度低于男性,但女性在研发投资过程中愿意投入的研发努力程度高于男性。随着时间推移,男性的研发努力程度明显下降,但女性的研发努力程度反而上升。男性和女性在决策中均表现出心理账户效应,女性更加愿意通过努力来提高业绩。男性在投资中更多体现期权思想,而女性更多表现出长期倾向下的持续努力。文章在揭示性别因素影响研发投资机理基础上,为董事会性别多样性、分级董事会以及递延薪酬等治理机制发挥作用机理提供了新解释。研究结论可以为企业职位的性别配置、分级董事会以及激励契约设计提供借鉴。 相似文献
112.
石油作为重要战略资源,对其组分进行实时分析检测在石油化工领域有着重要意义.随着石油资源的不断开发,在已长时间开采油井的生产过程中以及新油井开采前,需要对井下原油组分进行分析检测,以判定开采的必要性.原油组分实时检测,在原油开采、生产、储运以及销售过程中都起着关键的作用,针对传统检测方法存在精度低、效率低等问题,近年来在... 相似文献
113.
食源性致病菌是引发和威胁公众健康的主要因素之一.由于食源性致病菌种类繁多,常规检测方法复杂耗时要求高,因此迫切需要一种更加快速精确的致病菌检测技术.在传统红外光谱检测致病菌的流程中,如经典的溴化钾压片法,除了压片本身的操作之外通常还需对样品进行冷冻干燥(约需2 d)等耗时前处理过程,因而不利于高通量快速检测.本研究利用... 相似文献
114.
The structural stability and magnetic properties of the icosahedral Ni13, Ni13^+1 and Ni13^-1 clusters have been obtained by utilizing all-electron density functional theory with the generalized gradient approximations for the exchange-correlation energy. The calculated results show that the ground states of neutral and charged clusters all favour a D3d structure, a distorted icosahedron, due to the Jahn-Teller effect. The radial distortions caused by doping one electron and by doping one hole are opposite to each other. Doping one electron will result in a 1/2 decrease and doping one hole will result in a 1/2 increase of the total spin. Both increasing interatomic spacing and decreasing coordination will lead to an enhancement of the spin magnetic moments for Nil3 clusters. 相似文献
115.
Mid-infrared generation based on a periodically poled LiNbO3 optical parametric oscillator 下载免费PDF全文
We report a nanosecond Nd:YVO_4-pumped optical parametric oscillator (OPO) based on periodically poled LiNbO_3 (PPLN). Tuning is achieved in this experiment by varying the temperature and period of the PPLN. The design of double-pass singly resonant oscillator (DSRO) and confocal cavity enables the OPO threshold to be lowered considerably, resulting in a simple, compact, all-solid-state configuration with the mid-infrared idler powers of up to 466mW at 3.41μm. 相似文献
116.
Many authors have suggested new forms to describe the surface anchoring energy of the liquid crystal-wall interface, replacing the Rapini-Papoular (RP) formula g s = (1/2) A sin2 theta. If the RP function is considered as the primary approximation, and a lowest order modification is included, then the surface anchoring energy can be represented by g s = (1/2) A sin2 theta(1 + zeta sin2 theta). zeta characterizes the modification to the RP formula and varies for the different energy forms. It is well known that the RP formula predicts a second order Freedericksz transition. This paper points out that the transition can be first order if the modification is taken into account, in which case at the threshold point the tilt angle of the director at the middle layer of the cell, thetam, is finite. The conditions for the existence of the first order transition are obtained; zeta < 0 is required for a first order transition. The approximate expression of the threshold field is also given. 相似文献
117.
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119.
Radial flow reactor operated at cross-flow heat transfer is focused for large scale methanol synthesis. The effects of operating conditions including the reactor inlet air temperature, the heating pipe temperature and the air flow rate on the cross-flow heat transfer were investigated and results show that the temperature profile of the area in front of the heating pipe is slightly affected by all the operating conditions. The main area whose temperature profile is influenced is located behind the heating pipe. The heat transfer direction is related to the direction of the flow. In order to obtain the basic parameters for radial flow reactor designing calculation, the dimensionless number group method was used for data fitting of the bed effective thermal conductivity and the wall heat transfer coefficient which were calculated by the mathematical model with the product of Reynolds number and Prandtl number. The comparison of experimental data and calculated values shows that the calculated values fit the experimental data satisfactorily and the formulas can be used for reactor designing calculation. 相似文献
120.
Ying Liang Delong Liu Hou Chen 《Journal of polymer science. Part A, Polymer chemistry》2013,51(9):1963-1968
Well‐defined high oil‐absorption resin was successfully prepared via living radical polymerization on surface of polystyrene resin‐supported N‐chlorosulfonamide group utilizing methyl methacrylate and butyl methacrylate as monomers, ferric trichloride/iminodiacetic acid (FeCl3/IDA) as catalyst system, pentaerythritol tetraacrylate as crosslinker, and L ‐ascorbic acid as reducing agent. The polymerization proceeded in a “living” polymerization manner as indicated by linearity kinetic plot of the polymerization. Effects of crosslinker, catalyst, macroinitiator, reducing agent on polymerization and absorption property were discussed in detail. The chemical structure of sorbent was determined by FTIR spectrometry. The oil‐absorption resin shows a toluene absorption capacity of 21 g g?1. The adsorption of oil behaves as pseudo‐first‐order kinetic model rather than pseudo‐second‐order kinetic model. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献