A convenient neutron source is made for calibration of neutron survey instruments and personal dosimeters that are used in various nuclear installations such as fuel reprocessing, waste management, fuel fabrication and oil and well logging facilities, etc. This source consists of a bare (241)Am-Be neutron source placed at the centre of a 15-cm radius stainless steel spherical shell filled with distilled water. This paper describes the standardisation of the source at Bhabha Atomic Research Centre, using De Pangher neutron long counter both experimentally and using the Monte Carlo simulation. The ratio of neutron yield of water moderated to the bare (241)Am-Be neutron source was found to be 0.573. From the simulation, the neutron-fluence-weighted average energy of water-moderated (241)Am-Be source (fluence-weighted average energy of 2.25 MeV, dose-weighted average energy of 3.55 MeV) was found to be nearly the same as that of a (252)Cf source (fluence-weighted average energy of 2.1 MeV, dose-weighted average energy of 2.3 MeV). This source can be used for calibration in addition to (252)Cf, to study the variation in response of neutron monitoring instruments.
Accurate prediction of physicochemical properties, such as electronic energy, enthalpy, free energy, and average vibrational frequencies, is critical for optimizing lithium-ion battery (LIB) performance. Traditional methods like density functional theory (DFT) are computationally expensive and inefficient for large-scale screening. In this study, we apply active learning on top of graph neural networks (GNNs) to efficiently predict these properties.
To explore the direct and indirect effects of organic fertilizer application on greenhouse gas emissions from agricultural soils, a total of 1228 groups of data from 129 published studies were selected. Meta-analysis was used to analyze the effects of organic fertilizer on global greenhouse gas emissions from agricultural soils and their influencing factors. Meanwhile, a structural equation model （SEM） was further constructed to quantify and determine the causal relationships between the factors.
In this study, strategies for meeting the carbon peak and carbon neutral targets are developed through an in-depth analysis of future energy demand and carbon emission scenarios in Jiangsu Province. The LEAP model was used to forecast energy demand and carbon emissions under different scenarios from 2021 to 2060. Under the baseline scenario, the energy demand of key industries in Jiangsu Province showed a high rate of growth, with energy consumption increasing by 2.
Département des sciences animales, Université Laval, Pavillon Paul-Comtois, 2425 rue de l'Agriculture, Québec, QC, G1V 0A6, Canada. Electronic address:
In late gestation, the increased energy demand to support the rapid fetal growth can induce an acute negative energy balance associated with a high risk of pregnancy toxemia, especially for prolific ewes (carrying two or more fetuses). The current study was conducted to evaluate the effects of dietary energy during the last 6 weeks prepartum on the energy metabolism dynamic responses and the newborn lamb metabolic profile in prolific ewes. Forty-five crossbred (Dorset × Romanov) ewes were randomly assigned to 1 of 3 dietary energy densities: E: 8.
This study assessed the supplemental effect of flushing Menz breeding rams with local agro-industrial by-products on their reproductive performance and semen quality. In a completely randomized design, rams ( 49) with an initial weight of 25.69+2.
