Next-to-leading order QCD effect of W′W' on top quark Forward-Backward Asymmetry

We present the calculations of the complete next-to-leading order (NLO) QCD corrections to the total cross section, invariant mass distribution and the forward-backward asymmetry ($\rm A_{FB}$) of top quark pair production mediated by $W'$ boson. Our results show that in the best fit point in the parameter space allowed by data at the Tevatron, the NLO corrections change the new physics contributions to the total cross section slightly, but increase the $\rm A_{FB}$ in the large invariant mass region by about 9%. Moreover, we evaluate the total cross section and charge asymmetry ($\rm{A}_{\rm{C}}$) of top pair production at the LHC, and find that both total cross section and $A_{\rm C}$ can be used to distinguish NP from SM with the integrated luminosity increasing.Comment: 24 pages, 9 figures, 1 tabl

Multistaged discharge constructing heterostructure with enhanced solid-solution behavior for long-life lithium-oxygen batteries.

Inferior charge transport in insulating and bulk discharge products is one of the main factors resulting in poor cycling stability of lithium-oxygen batteries with high overpotential and large capacity decay. Here we report a two-step oxygen reduction approach by pre-depositing a potassium carbonate layer on the cathode surface in a potassium-oxygen battery to direct the growth of defective film-like discharge products in the successive cycling of lithium-oxygen batteries. The formation of defective film with improved charge transport and large contact area with a catalyst plays a critical role in the facile decomposition of discharge products and the sustained stability of the battery. Multistaged discharge constructing lithium peroxide-based heterostructure with band discontinuities and a relatively low lithium diffusion barrier may be responsible for the growth of defective film-like discharge products. This strategy offers a promising route for future development of cathode catalysts that can be used to extend the cycling life of lithium-oxygen batteries

Interlayer Coupling of Co/NM/FM(NiFe and Co) Nano-Sandwich Films

AbstractCu/Co, Cu/NiFe, Ta/NiFe bilayers and Co/Cu/Co, Co/Cu/NiFe, Co/Ta/NiFe sandwich films were deposited by a magnetron sputtering method. Magnetic properties were evaluated by VSM and spin valve magnet oresistance was investigated by a four-probe method to study the interlayer coupling of the two magnetic layers. It has been found that the interlayer coupling depended not only on the layer thickness of the nonmagnetic spacer but also on the nature of the spacer. The interlayer coupling was reduced as the spacer layer thickness increased. The result was consistent with those from observations of the magnetic domain for the trilayers by means of Lorentz Electron Microscope. The trilayers with Cu spacer layer have shown a stronger coupling than those with Ta spacer layer

Divergent and Stereoselective Synthesis of β-Silyl-α-Amino Acids through Palladium-Catalyzed Intermolecular Silylation of Unactivated Primary and Secondary C−H Bonds

A general and practical Pd^(II)-catalyzed intermolecular silylation of primary and secondary C−H bonds of α-amino acids and simple aliphatic acids is reported. This method provides divergent and stereoselective access to a variety of optical pure β-silyl-α-amino acids, which are useful for genetic technologies and proteomics. It can also be readily performed on a gram scale and the auxiliary can be easily removed with retention of configuration. The synthetic importance of this method is further demonstrated by the late-stage functionalization of biological small molecules, such as (−)-santonin and β-cholic acid. Moreover, several key palladacycles were successfully isolated and characterized to elucidate the mechanism of this β−C(sp^3)-H silylation process

The influence of knowledge-based HRM practices on productivity of knowledge workers: A Study on Malaysian universities

Knowledge workers have contributed significantly to the development of nations. There are various researches that extensively recognized the positive impact of knowledge-based HRM practices on knowledge worker's productivity. While there are studies regarding knowledge-based HRM practices across different countries and industries, however, there is dearth of research regarding the impact of knowledge-based HRM practices on universities' knowledge workers. Therefore, the aim of this current study was to fill up the gap by analysing the influence of various knowledge-based HRM practices on the productivity of knowledge workers in universities. This study investigated HRM practices namely knowledge-based recruiting practices, knowledge-based training and development practices, knowledge-based performance appraisal practices and knowledge-based compensation practices on the quality and quantity of the productivity of knowledge workers. Herzberg's Two-Factor Theory, Expectancy Theory, and MacGregor's Theory X and Theory Y were used as underpinning theories to support the proposed conceptual model. Eight hypotheses were developed based on the proposed research model and standard instrument was used to obtain data. By employing non-probability sampling method, a total of 129 knowledge workers in Selangor and Kuala Lumpur participated in survey. The data were collected at one point of time across the sample population. The data obtained were assessed using SPSS and Partial Least Square Structural Equation Modelling (PLS-SEM). Results revealed the positive and significant influence of knowledge-based recruiting practices and knowledge-based compensation practices on quality and quantity of knowledge workers' productivity. Knowledge-based training and development practices were found to have their positive and significant impact on quantity of knowledge workers' productivity but not on quality of knowledge workers' productivity. Additionally, knowledge-based performance appraisal was not found to have its positive as well as significant impact on quality and quantity of knowledge worker's productivity

Design Change Model for Effective Scheduling Change Propagation Paths

Changes in requirements may result in the increasing of product development project cost and lead time, therefore, it is important to understand how requirement changes propagate in the design of complex product systems and be able to select best options to guide design. Currently, a most approach for design change is lack of take the multi-disciplinary coupling relationships and the number of parameters into account integrally. A new design change model is presented to systematically analyze and search change propagation paths. Firstly, a PDS-Behavior-Structure-based design change model is established to describe requirement changes causing the design change propagation in behavior and structure domains. Secondly, a multi-disciplinary oriented behavior matrix is utilized to support change propagation analysis of complex product systems, and the interaction relationships of the matrix elements are used to obtain an initial set of change paths. Finally, a rough set-based propagation space reducing tool is developed to assist in narrowing change propagation paths by computing the importance of the design change parameters. The proposed new design change model and its associated tools have been demonstrated by the scheduling change propagation paths of high speed train’s bogie to show its feasibility and effectiveness. This model is not only supportive to response quickly to diversified market requirements, but also helpful to satisfy customer requirements and reduce product development lead time. The proposed new design change model can be applied in a wide range of engineering systems design with improved efficiency

Reconsideration of Second Harmonic Generation from neat Air/Water Interface: Broken of Kleinman Symmetry from Dipolar Contribution

It has been generally accepted that there are significant quadrupolar and bulk contributions to the second harmonic generation (SHG) reflected from the neat air/water interface, as well as common liquid interfaces. Because there has been no general methodology to determine the quadrupolar and bulk contributions to the SHG signal from a liquid interface, this conclusion was reached based on the following two experimental phenomena. Namely, the broken of the macroscopic Kleinman symmetry, and the significant temperature dependence of the SHG signal from the neat air/water interface. However, because sum frequency generation vibrational spectroscopy (SFG-VS) measurement of the neat air/water interface observed no apparent temperature dependence, the temperature dependence in the SHG measurement has been reexamined and proven to be an experimental artifact. Here we present a complete microscopic analysis of the susceptibility tensors of the air/water interface, and show that dipolar contribution alone can be used to address the issue of broken of the macroscopic Kleinman symmetry at the neat air/water interface. Using this analysis, the orientation of the water molecules at the interface can be obtained, and it is consistent with the measurement from SFG-VS. Therefore, the key rationales to conclude significantly quadrupolar and bulk contributions to the SHG signal of the neat air/water interface can no longer be considered as valid as before. This new understanding of the air/water interface can shed light on our understanding of the nonlinear optical responses from other molecular interfaces as well