This research was aimed at estimating possible Coal workers’ pneumoconiosis (CWP) cases as of 2012, and predicting future CWP cases among redeployed coal workers from the Fuxin Mining Industry Group. This study provided the scientific basis for regulations on CWP screening and diagnosis and labor insurance policies for redeployed coal workers of resource-exhausted mines. The study cohort included 19,116 coal workers. The cumulative incidence of CWP was calculated by the life-table method. Possible CWP cases by occupational category were estimated through the average annual incidence rate of CWP and males’ life expectancy. It was estimated that 141 redeployed coal workers might have suffered from CWP as of 2012, and 221 redeployed coal workers could suffer from CWP in the future. It is crucial to establish a set of feasible and affordable regulations on CWP screening and diagnosis as well as labor insurance policies for redeployed coal workers of resource-exhausted coal mines in China.

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A new project, high intensity heavy ion accelerator facility (HIAF), is currently under design and construction in China. The HIAF front end, composed of electron cyclotron resonance (ECR) ion sources, low energy beam transport (LEBT) and radio frequency quadrupole (RFQ), will produce and provide beams of ions with a mass up to uranium at a beam energy of 0.5 MeV=u. The typical beam intensity is designed up to 2 emA for the uranium beam with a charge state of 35þ. This paper presents an overall design of the front end for HIAF and discusses several key issues in the design. By modeling the beam extraction from the ECR source, we got a reliable starting beam condition to perform the design. Transverse coupling of the beam from the source was elaborated. To relieve the coupling we implanted two solenoids after the source. Space charge effect in the charge state selection of the ion source was evaluated. An overall space charge compensation degree of no less than 70% was predicted. A beam dynamics simulation was performed by using the initial particle distribution obtained from the extraction modeling. The simulation resulted in development of a beam collimation system in the LEBT to confine the transverse emittance. The RFQ design will follow the development of LEAF-RFQ at Institute of Modern Physics, which has successfully commissioned with several beams and demonstrated as an excellent design. Recent beam commissioning results of LEAF-RFQ will also be presented in this paper.

A Low Energy high-intensity high-charge-state ion Accelerator Facility (LEAF), which mainly consists of a 45 GHz superconducting ECR ion source, LEBT and a 81.25 MHz 4-vane RFQ, was designed to produce and accelerate heavy ions, from helium to uranium with A/Q between 2 and 7, to the energy of 0.5 MeV/u. The typical beam intensity is designed up to 2 emA CW for the uranium beam. The project was launched in 2015 and has been successfully commissioned with He+ (A/Q=4), N2+ (A/Q=7) beam and accelerated the beams in the CW regime to the designed energy of 0.5 MeV/u. Beam commissioning results of He+ beam have been reported previously. This paper presents the details of N2+ commissioning and beam studies.