An important factor for the high performance of lightharvesting devices is the presence of surface trappings. Therefore, understanding and controlling the carrier recombination of the organic−inorganic hybrid perovskite surface is critical for the device design and optimization. Here, we report the use of aluminum zinc oxide (AZO) as the anode to construct a p−n junction structure MAPbBr 3 nuclear radiation detector. The AZO/MAPbBr 3 /Au detector can tolerate an electrical field of 500 V•cm −1 and exhibit a very low leakage current of ∼9 nA, which is 1 order of magnitude lower than that of the standard ohmic contact device. The interface state density of AZO/MAPbBr 3 contact was reduced from 2.17 × 10 10 to 8.7 × 10 8 cm −2 by annealing at 100°C under an Ar atmosphere. Consequently, a photocurrent to dark current ratio of 190 was realized when exposed to a green light-emitting diode with a wavelength of 520 nm (∼200 mW•cm −2). Simultaneously, a high X-ray sensitivity of ∼529 μC•Gy air −1 cm −2 was achieved under 80 kVp X-ray at an electric field of 50 V•cm −1. These results demonstrate the use of surface engineering to further optimize the performance of MAPbBr 3 detectors, which have many potential applications in medical and security detection with low radiation dose brought to the human body.

Purely organic 4HCB single crystals show a capability of directly detecting 241Am 5.49 MeV α particles and X-ray imaging under low-dose rate (below 50 μGyair s−1) exposure conditions.

This paper discusses a new method of background estimation in the energy‐dispersive X‐ray fluorescence (EDXRF) analysis, which is based on Fourier Transform (in this paper, we call it Fourier Transform background estimation method). Compared with the Sensitive Nonlinear Iterative Peak method, the new method has the feature of FWHM independence. It has been proved that a background can be estimated automatically and accurately by the new method in the synthesized spectrum and the spectra from measurement. Fourier Transform background estimation method can estimate the background accurately in the EDXRF spectrum using an X‐ray tube source. Copyright © 2011 John Wiley & Sons, Ltd.

Calculation method is a very important basic course of engineering, in the environment of engineering education, a large number of colleges and universities bring calculation methods into the category of professional compulsory courses. This course is not only theoretical, but also practical. Therefore, teachers are required to combine the two organically. The evaluation of teaching quality is of great practical significance to the cultivation of students and the optimization of curriculum. This paper establishes a more convenient and efficient teaching quality evaluation model of calculation method course by making corresponding evaluation index of calculation method course, and proves its excellence through experiments.