In modern times, with the rapid development of technology, science and economy, applications of electromagnetic (EM) wave absorption in both commercial and military fields have increased. Meanwhile, the problems brought by EM wave absorption have gradually become obvious, such as signal interference, back-radiation of microstrip radiators and so on. Furthermore, the impact of EM wave radiation on human health has also attracted much public attention. In this regard, the application of EM wave absorbing materials has become a focus of current research. Due to their unique chemical, physical, and mechanical properties, carbon nanotubes (CNTs), through certain modifications for light mass, wide range and strong absorption, have great potential to be used as excellent EM wave absorbents. This review highlights recent research into the modification of CNTs, with special emphasis on their EM wave absorbing ability.

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Pedestrians are vulnerable road users of the traffic system. In China, many pedestrians lack a knowledge of traffic rules and are not fully aware of safety problems. A high-risk area for pedestrians, the unsignalized midblock crosswalk is a conflict zone between pedestrians and through vehicles. In this paper, behaviors and traffic characteristics of pedestrians walking through the unsignalized midblock crosswalk without being disturbed by other pedestrians are analyzed. The data, including pedestrian speed, waiting delay, and clustering, are obtained by counting and measuring with a video camera. Pedestrian behaviors are analyzed with the use of comparisons between various categories and through statistics analysis. Pedestrian behaviors are interpreted further by analyzing pedestrians’ tactics when they cross the street and the valid gap in the vehicle flow, based on observations and measurements of pedestrians starting to walk across and of vehicle arrivals. Finally, the similarities and differences between this research and other research is explained by comparing pedestrian speed studies. Results of this research will not only help improve research on pedestrian characteristics at interrupted pedestrian facilities but will also help in developing traffic safety audit work and related countermeasures.

Transmission of a quantum state is essential for performing quantum information processing tasks. The communication channel will be inevitably immersed in its surrounding environment under realistic conditions. In this paper, we investigate the influence of environment noise on the transmission fidelity when transferring a quantum state through a spin chain. The non-Markovian open system dynamics is systematically analyzed by using the quantum state diffusion equation method. With each spin immersed in its own finite temperature and non-Markovian heat bath, we consider three types of system–bath interaction: dephasing, dissipation and spin-boson. The transmission fidelity is found to decrease with the increasing bath temperature and system–bath coupling strength. Interestingly, we find that the bath non-Markovianity can help enhancing the transmission fidelity.

Shortcuts to adiabaticity" represents a strategy for accelerating a quantum adiabatic process, is useful for preparing or manipulating a quantum state. In this paper, we investigate the adiabaticity in the dynamics of an XY spin chain. During the process of cutting one long chain into two short chains, a "shortcut" can be obtained by applying a sequence of external pulses. The fidelity which measures the adiabaticity can be dramatically enhanced by increasing the pulse strength or pulse duration time. This reliability can be kept for different types of pulses, such as random pulse time interval or random strength. The free choice of the pulse can be explained by the adiabatic representation of the Hamiltonian, and it shows that the control effects are determined by the integral of the control function in the time domain.

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