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The yields of 85Krm, 87Kr and 88Kr of neutron-induced fission of 239Pu are important nuclear parameters. They have a moderate half-life, are β- decay and emission γ-rays with a certain probability, so it is appropriate to use γ-ray spectrum method to determine their yield. At present, there are few experimental data with large deviation abroad and no experimental results have been reported in China. The yield measurements of 85Krm, 87Kr and 88Kr of thermal-neutron-induced fission of 239Pu were carried out based on the irradiation of plutonium target by Xi’an Pulsed Reactor rabbit system. The purified plutonium solution was then titrated and dried to prepare the silica-encapsulated plutonium target. Three kinds of measurement experiments were designed: γ-ray nondestructive method for the relative yield of 88Kr and 99Mo, gas-solid separation method for 85Krm, 87Kr and 88Kr and γ-ray nondestructive method for the relative yield of 85Krm, 87Kr and 88Kr. After the target irradiation and cooling, the fission products were measured by the above-mentioned methods. The efficiency of the three kinds of experimental samples was calibrated by the equivalent efficiency curve method. The plan source of organic glass package was used to equate the efficiency calibration of quartz tube source, and the plan source of stainless steel package with the same thickness and material as the measuring source was used to equate the efficiency calibration of 50 mL gas source. By Monte Carlo simulation, the suitable equivalent position was selected, and the efficiency value was fine corrected (less than 0.8%). The uranium target was prepared in the same way of plutonium target. The relative yields of 85Krm, 87Kr and 88Kr of 235U fission induced by thermal neutron measured by gas-solid separation after irradiation are consistent with the recommended values of the evaluation database, which indicates that the release rates of 85Krm, 87Kr and 88Kr in the plutonium target are the same. After modified by the influence of non-primary neutron field and non-primary isotope, the fission yields of 85Krm, 87Kr and 88Kr were obtained based on the measured relative yield with reference product 99Mo and the yield of 99Mo given by ENDF/BⅧ.0 evaluation database. The measured yields are (0.559±0.020)%, (0.992±0.034)% and (1.264±0.037)%, respectively, which are consistent with the evaluation value of the database and the uncertainty is significantly reduced compared with other literature value. In this paper, the retrieval and deduction methods of γ-ray energy peak interference ratio in measurement are universal, but the uncertainty of theoretical yield may be added. The experimental method in this paper can also provide reference for the measurement of fission product yield at different neutron energy points.

Controlling the optical activity of halide perovskite materials through modulation of the coordination configurations of the metal ions is important. Herein, a novel manganese‐based halide, specifically diaquatetrakis(methyldiphenylphosphine oxide)manganese(II) tetrachloridomanganate(II), [Mn(C13H13OP)4(H2O)2][MnCl4] or [Mn(MDPPO)4(H2O)2][MnCl4] (MDPPO is methyldiphenylphosphine oxide), was synthesized through the solvothermal reaction of MnCl2 with the neutral molecule MDPPO. In this compound, [Mn(MDPPO)4(H2O)2]2+ acts as the cation, while [MnCl4]2− serves as the anion, enabling the co‐existence of tetrahedral and octahedral structures within the same system. Remarkably, the compound exhibits efficient red‐light emission at 662 nm, distinct from the green‐light emission typically observed in MnX4‐based halides. Theoretical calculations show that the red emission comes from the charge transfer from the MDPPO to the Mn2+ of [MnCl4]2−. This work provides a new perspective for the design and synthesis of red‐light‐emitting manganese‐based halides with unique structures. [ABSTRACT FROM AUTHOR]

Organic carbon in grassland mainly exists in the soil, and root production and turnover play important roles in carbon input into the soil. However, the effects of climate change on plant root dynamics in desert steppe are unknown. We conducted an experiment in a desert steppe, which included ambient temperature (T0); temperature increased by 2 °C (T1); temperature increased by 4 °C (T2); natural precipitation (P0); precipitation increased by 25% (P1); precipitation increased by 50% (P2); and the interaction between warming and increased precipitation. Plant community aboveground characteristics; root production; and root turnover were measured. We found that the root length production of the T0P2; T1P1; T2P0; and T2P1 treatments were significantly higher than that of the T0P0 treatment, with an increment of 98.70%, 11.72%, 163.03%, and 85.14%, respectively. Three treatments with temperature increased by 2 °C (T1P0; T1P1; and T1P2) and significantly increased root turnover rate compared to the T0P0 treatment, with increases of 62.53%, 42.57%, and 35.55%, respectively. The interaction between warming and increased precipitation significantly affected the root production of the community (p < 0.01), but this interaction was non-additive. Future climate warming will benefit the accumulation of root-derived carbon in desert steppe communities. [ABSTRACT FROM AUTHOR]

The article raises the issue regarding the possibilities of using musical noise instruments in the process of mass art education. The relevance of the topic is predetermined by these facts: a) insufficient attention of representatives of musical education to the use of musical noise instruments; b) the growing importance of this type of instrument in academic and popular music; c) increasing interest of modern youth in instrumental music making; b) the low degree of development of the theory and methodology of playing musical noise instruments. The goal of the work is to consider the phenomenon of musical noise instruments from the education viewpoint as well as to determine their pedagogical potential. The content of the article. Based on the analysis of special literature, the classification concept “musical noise instruments” has been specified. Their mechanical, acoustic, plastic, cultural and educational properties have been characterised. The features of musical noise instruments that determine the possibility and expediency of their use in the practice of musical education have been determined. The results of the study. It is proposed to understand “musical noise instruments” as acoustic mechanical devices that allow creating more or less plastic broadband and colour noises. It has been established that musical noise instruments have an important educational value, which can be explained by a number of factors: a) these instruments belong to the oldest sound generation devices in the history of mankind, familiarity with them serves to expand cultural knowledge and gnostic motivation for art education; b) mastery of them opens the way for developing traditions of the native national art and the wealth of other national cultures; c) musical noise instruments primarily serve to reproduce the musical rhythm in all its expressiveness and structural complexity; involvement of schoolchildren in playing music with musical noise instruments promotes the development of their musical and rhythmic abilities, perceptions and skills; d) since the role of musical noise instruments today has significantly increased in the practice of classical, jazz and popular music, the acquaintance of students with these instruments should be considered as one of the ways to master the poetics and artistic language of modern music in its various style and genre manifestations; e) musical noise instruments have a high potential in attracting preschool children and primary school pupils to active ensemble music playing. Modern pedagogy of higher education should study and develop the didactic capabilities of musical noise instruments in training future teachers of musical art: the formation of their sense of rhythm, texture, architectonics, timbre palette, intonational expressiveness; arranging skills, expanding musical and cultural experience. These tasks require an appropriate technique, the development of which is the author’s further task.