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Supplementary information and introduction of bi-material iBEM

Manipulation of the intersublattice interaction strengh (JRE-TM) in rare earth (RE)-transition metal (TM) alloys is a key issue to understand how efficiently the laser-induced angular momentum transfers from 3d to 4f spins and to have a better control of the ultrafast spin dynamics. In this work, the relationships between laser-induced demagnetization process and the intersublattice 3d-4f interaction for the GdCoFe alloys were systematically studied. The ultrafast two-stage demagnetization process could change into a one-stage mode as the angular momentum transferring channel between 3d and 4f spins is switched off, which could be modulated by JRE-TM. Furthermore, both the effective g-factor and damping constant deduced by the subsequently laser-induced magnetization precession process diverge at the angular momentum compensation point based on the ferromagnetic resonance method with the LLG equations. The results provide an alternative way to efficiently manipulate the ultrafast demagnetization time for practical applications.

A topic of ongoing debate in survey research is whether items measuring different constructs should be grouped by construct or intermixed. Previous researchers have failed to reach a consensus on whether grouping or intermixing measurement items leads to better construct validity. The inconsistency of their findings has to a large extent resulted from a tendency to confound true variance and systematic error variance. Drawing on measurement and cognitive theories, we propose that for established measures with satisfactory psychometric properties, grouped items capture less unsystematic and systematic error variance and more true variance than their intermixed counterparts. This argument is supported by the findings of a field experiment with 853 students in 142 project teams, who reported their teams’ relationship and task conflict on grouped and intermixed items. The theoretical and practical implications of these findings for researchers who use survey instruments are discussed.

Terahertz radiation generation from liquid water has long been considered to be impossible due to strong absorption. A few very recent works reported terahertz generation from water, but the mechanism is not clear and the efficiency demands to be enhanced. We show experimentally that strong single-cycle terahertz radiation with field strength of $\rm 0.2~MV cm^{-1}$ is generated from a water line/column of $\sim 200 \mu m$ in diameter irradiated by a mJ femtosecond laser beam. This strength is 100-fold higher than that produced from air. We attribute the mechanism to the laser-ponderomotive-force-induced current with the symmetry broken around the water-column interface. This mechanism can explain our following observations: the radiation can be generated only when the laser propagation axis deviates from the column center; the deviation determines its field strength and polarity; it is always p-polarized no matter whether the laser is p- or s-polarized. This study provides a simple and efficient scheme of table-top terahertz sources based on liquid water., Comment: 4 figures

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Pot experiments were performed to investigate the responses of nitrogen metabolism to copper stress in Luffa cylindrica roots. Four treatments were used, in which varying copper concentrations (25, 50, 75 and 100 µM ) were added to MS medium. The fresh weights of the roots decreased gradually with the increasing copper concentrations. At the lower concentrations, the ammonium and nitrite levels increased compared with the control, but the nitrate concentrations significantly decreased with 75 and 100 µM copper. Compared with the control, nitrate reductase activity levels gradually increased with increasing copper concentrations of up to 50 µM, and nitrite reductase activity levels significantly decreased. Copper stress led to variable increases in the activities of glutamine synthetase and glutamate synthase compared with the controls. The NADH- glutamate dehydrogenase (NADH-GDH) and NAD-glutamate dehydrogenase (NAD-GDH) activities were affected by the copper treatments, but that of NAD-GDH was significantly reduced by 100 µM copper. The activities of alanine aminotransferase (AlaAT) and aspartate aminotransferase (AspAT) showed varying changes following the copper treatments. The present results indicate that Luffa cylindrica shows altered activities of enzymes associated with nitrogen metabolism during copper stress, enabling it to monitor and adapt to changes in its N status and supply, thereby minimizing the harmful effects of the stress.

Narrow-band-gap semiconductor quantum dots (QDs) are considered as next-generation sensitizers for solar cells because of their extraordinary optical and electrical properties in terms of tuneable band gap, high molar extinction coefficient, and large intrinsic dipole moment, which may facilitate charge separation in solar cells. Moreover, theoretical photovoltaic conversion efficiency of QDs-sensitized solar cells can reach up to 44% in view of multiple exciton generation (MEG).(Published: 11 June 2013)Citation: Nano Reviews 2013, 4: 21080 - http://dx.doi.org/10.3402/nano.v4i0.21080

We presented that the relaxation of n coupling molecules in a molecular string exhibits n individual relaxation modes (RMs), each mode being characterized by a definite relaxation time and amplitude according to the string model. The n RMs behaving a single relaxation at high temperature, evolves to two relaxation species, at low temperature, with different temperature dependences for the respective relaxation times and amplitudes. Since the characteristics of the two relaxation species are in agreement with those exhibited by the universal alpha- and Johari-Goldstein (JG) beta-relaxations in glass dynamics, we provided a unified molecular level mechanism for these two processes., 9 pages, 2 figures

The string relaxation equation (SRE) of the string model for the glass transition contains the well-known Debye and Rouse-Zimm relaxation equations. However, its initial condition, necessary to the model predictions of glassy dynamics, such as the mechanism of the universal primary alpha- and Johari-Goldstein beta-relaxations in glassformers, has not been solved. In this paper, the special initial condition (SIC) of the SRE of straight strings for dielectric spectrum technique, which is one of the most common methods to measure the glassy dynamics, was tentatively calculated by a direct calculation method, finding that the method has not any practical feasibility. However, a recursive calculation method was developed that allows to obtain the SIC exactly. It should be expected that the obtained SIC would benefit the thorough solution of the general initial condition of the SRE of the string model for stochastically spatially configurating strings, as will be described in separate publications., 13 pages, 3 figures