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The cross-sections of the 187Re(n,γ)188mRe and 187Re(n,γ)188gRe reactions were measured at the four neutron energies of 13.5, 14.1, 14.4 and 14.8 MeV through the activation method and using off-line γ-ray spectrometry. The previously developed formulas were used to subtract the effects of γ rays with close energies and the contribution from the excited state. A high-resolution γ-ray spectrometer with high-purity germanium detector was used to measure the induced γ activities. The simulation computations of the excitation functions concerning the above-mentioned two nuclear reactions were performed by adopting the nuclear theoretical model program system Talys-1.9. The theoretical excitation curves in the incident neutron energy range from 2.53 × 10−8 to 20 MeV were acquired. The fitting line of our results in the neutron energy range of 13.5–14.8 MeV, within experimental uncertainty, agrees very well with the theoretical excitation curve based on the computer code Talys-1.9.

The objective of this study was to analyze the effects of additives (biochar (BC) and palygorskite (PG)) on predominant fungi succession throughout composting of corn stover/chicken manure mix to influence humic substances formation (HS). Results indicated that BC and PG promoted the polymerization of HS and formation of more humic acids (HA), and BC performed better than PG, 10% additive was better than 5%. ITS rRNA gene sequencing showed that predominant fungi succession was significantly affected by BC and PG in composting, correlation between HS formation and predominant fungi indicated that BC and PG boosted lignocellulose-degrading fungi which could break down fulvic acids (FA) and HM to form more HA. Fungi function analysis showed that 10% BC significantly increased saprotrophic fungi, and decreased pathogenic fungi. Therefore, addition of 10% BC was conductive to promote the formation of HA and improve compost quality.

The first experimental cross-section data for the 180Hf(n,γ)181Hf reaction have been measured within the neutron energies range of 13.5–14.8 MeV using the activation technique. The fast neutrons were produced by the T(d,n)4He reaction. Induced activities were measured by a high-resolution γ-ray spectrometer with high-purity germanium detector. The neutron fluence was determined by using the monitor reaction 93Nb(n,2n)92mNb. The neutron energies in the measurements were determined beforehand by the method of cross section ratios for the 90Zr(n,2n)89m+gZr and 93Nb(n,2n)92mNb reactions. The experimentally determined cross-section values were compared with the evaluation nuclear data in several major libraries of International Atomic Energy Agency and the theoretically calculated results by using the Talys1.8 code.

The cross sections of the 180Hf(n,p)180Lu and 90Zr(n,2n)89mZr reactions were measured around the neutron energies of 13.5–14.8 MeV by using the activation technique. The excitation functions of the above reactions in the neutron energies from the threshold to 20 MeV were calculated by using the nuclear theoretical model program system Talys-1.9 with the adjusted relevant parameters. The measured results were discussed and compared with previous experiments by other researchers and with the evaluated data of ENDF/B-VIII.0, CENDL-3.1, JEFF-3.3, JENDL-4.0u2, BROND-3.1 as well as the theoretical values based on Talys-1.9. The obtained experimental values at some neutron energies, within experimental error, are consistent with those of the fitting line of the results of previous experiments and are also consistent with those of theoretical excitation curve at the corresponding energies. The obtained theoretical excitation curves match well with most of the experimental data.