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Additional file 1: Figure S1. Rarefaction curves in all samples. Figure S2. Correlation and cluster analysis of nutritional components in medium based on Spearman correlation coefficient.

High-precision measurement of X-ray spectra is affected by the statistical fluctuation of the X-ray beam under low-counting-rate conditions. It is also limited by counting loss resulting from the dead-time of the system and pile-up pulse effects, especially in a high-counting-rate environment. In this paper a detection system based on a FAST-SDD detector and a new kind of unit impulse pulse-shaping method is presented, for counting-loss correction in X-ray spectroscopy. The unit impulse pulse-shaping method is evolved by inverse deviation of the pulse from a reset-type preamplifier and a C-R shaper. It is applied to obtain the true incoming rate of the system based on a general fast–slow channel processing model. The pulses in the fast channel are shaped to unit impulse pulse shape which possesses small width and no undershoot. The counting rate in the fast channel is corrected by evaluating the dead-time of the fast channel before it is used to correct the counting loss in the slow channel.

Some key temperature parameters in the process of controlled rolling and controlled cooling of N80 grade oil casing steel were simulated by heat treatment method, and the effects of different isothermal temperatures on the microstructure and mechanical properties of N80 grade oil casing steel were studied. The results show that when the isothermal temperature increases from 500 °C to 550 °C, the influence of different microstructure volume and grain size is not obvious; when the temperature reaches 600 °C, the ferrite grain coarsens obviously, the volume fraction of ferrite increases obviously, and the volume fraction of pearlite and bainite decreases obviously. In addition, when the isothermal temperature increases from 500 °C to 550 °C, the yield strength and tensile strength of the test steel increase slightly, and the plastic toughness increases obviously; but when the temperature increases to 600 °C, the yield strength and tensile strength of the test steel decrease obviously, and the plastic toughness continues to increase. The optimum isothermal treatment temperature of test steel is 550 °C.

This paper analyzes the intelligent and digital trend of remanufacturing industry, discusses the connotation and characteristics of additive remanufacturing technology, compares and analyzes the application status and application technology of additive remanufacturing technology in China’s military industry, points out that additive remanufacturing technology has broad application prospects in national defense science and technology, and brings higher military and economic benefits.

By analyzing the multi-year runoff and rainfall data at 15 hydrological stations from 1980 to 2007, as well as monthly runoff data from 1964 to 1984 at the Zipingpu hydrologic station, the relationship between precipitation and runoff has been established and the trend was explored. Based on the catastrophic floods of August 13 and August 18, 2010, characteristics and control factors on the post-seismic floods are summarized. Firstly, the Wenchuan earthquake and rupture zone provides the background for post-seismic floods to develop in the upper Minjiang River, which follows a post-seismic disaster-chain pattern: earthquake collapse to landslide debris flows to floods. Secondly, heavy rainfall controlled by the orographically-enhanced precipitation after the Wenchuan earthquake is the trigger factor for the development of devastating post-seismic floods. Thirdly, the post-seismic floods contain high sediment discharge, cause abrupt and severe damages, and have a large of volume and higher frequency.