[en] 'Dirty bomb', one of the three nuclear and radiological terrorism attack events, is a kind of weapon using conventional explosive to disperse radioactive materials, which leads to harmful and serious environmental contamination with α, β, γ rays and neutron having high radioactivity activity. This paper mainly introduces the characteristics and hazards, and puts forward some recommendations to counter RDD based on current international and national situations in nuclear and radiological terrorisms. (authors)

[en] Detecting, monitoring, identifying and tracking radioactive material, for health physics, safeguards, homeland security and mapping its distribution have become high-priority tasks. It is of significant importance to design a coded aperture gamma radiation imaging system. In this paper, we determine the parameters of the coded-aperture system through existed coded aperture theories and simulation to achieve high sensitivity, large field of view, best image quality and also acceptable spatial resolution. (authors)

[en] The problem of neutron source energy spectrum was solved by measuring the etching track parameters in CR39 SSNTD. The new concept of amendments to etching thickness was put for ward. How to get the numerical value of characteristic parameters could be informed. The assumption of neutron source energy spectrum to be solved using CR39 SSNTD was possible changed into reality

[en] The problem of neutron source energy spectrum was solved by measuring the etching track parameters in CR39 SSNTD. The new concept of amendments to etching thickness was put forward. The Problem of getting the numerical value of characteristic parameters has been solved, so that the assumption of solving the neutron source energy spectrum using CR39 SSNTD could be turned into reality

[en] In this article, a summary of CdZnTe detector for astrophysics applications is provided. The main properties of CdZnTe crystal and the principle of CdZnTe detector are introduced. The applications of CdZnTe detector in the astrophysics are summarized. The characters of applications and the development trend are discussed at four aspects. (authors)

[en] Detecting, monitoring, identifying and tracking radioactive material, for health physics, safeguards, homeland security and mapping its distribution have become high-priority tasks. It is of significant importance to design a coded aperture gamma radiation imaging system. In this paper, we determine the parameters of the coded-aperture system through existed coded aperture theories and simulation to achieve high sensitivity, large field of view, best image quality and also acceptable spatial resolution. (authors)

[en] The track etch dynamics model of isotropic solid state nuclear track detector at a varied etching rate was set up. A set of formulas for etching parameters was given. The calculating precision was raised by using new model. There was better energy-resolution of α and proton spectrum

[en] The irradiance on the earth synchronous orbit and median orbit in the standard atmosphere was computed. The dynamic range and the sensitivity of the detector were drawn, and the feasibility was analyzed also. Detection of the irradiance and the power would not be effected when the detector on the ISGO or similar GPS constellation. (authors)

[en] The threat of nuclear terrorism is described, and the need of nuclear monitoring for counter nuclear terrorism is discussed. (authors)

[en] The damage effect math-model of initial nuclear radiation for neutron bomb nuclear explosion is studied. (authors)