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Fissile material dissolved in the molten salt is employed in molten salt reactor(MSR), which circulates through the primary loop. Considering the flow characteristic of fuel in MSR, the neutron poison calculation model such as Xe is different from traditional solid reactor. As an important neutron poison, 135Xe is free to migrate with the flow of molten salt in MSR. The helium bubble system of molten salt reactor can blow the fission products of krypton, xenon and other gases out of the reactor core to improve the neutron economy. The recent TENDL2021 nuclear data library estimates the thermal neutron absorption cross section of 135Xem, which is much higher than 135Xe thermal neutron absorption cross section. In order to predict the effect of xenon on core reactivity more accurately, the effect of 135Xem thermal neutron absorption cross section was added into the Xe poison model based on the lumped volume method. The migration model is made up of cover gas calculation model and xenon worth calculation model. In order to calculate the xenon worth, the loop void fraction was calculated firstly, and the loop void fraction was inserted into the xenon worth calculation model. According to the rate balance equations and mass transfer equations, the concentration of xenon in loop could be calculated to compute the xenon worth. Firstly, the model results considering the flow effect of fuel salt were verified with the experimental results of 8 MW molten salt reactor experiment (MSRE). As the results shown, with the increase of loop void fraction, the steadystate xenon worth increases first and decreases later, which is in good agreement with experimental results of MSRE. Then the influence of fuel salt types and 135Xem on steadystate xenon worth was considered in this paper. The steadystate xenon worth of the 233U system with and without 135Xem is made and compared to a 235U system, indicating that the influence of 135Xem on xenon worth cannot be ignored, which is much higher with the increase of power. Finally, the contribution of graphite, fuel salt and helium bubble to Xe worth was evaluated by the interaction between graphite and helium bubble, indicating that the interaction between helium bubble and graphite cannot be ignored.

Objective * To establish the reference intervals of serum anti-Müllerian hormone (AMH) in healthy women of childbearing age in different age groups in Shanghai. Methods * A total of 239 healthy women of childbearing age, who accepted staff physical examination in International Peace Maternity and Child Health Hospital, Shanghai Jiao Tong University School of Medicine, during July 2019, were enrolled and detected for serum AMH level using chemiluminescence immunoassay. After the outlier exclusion, 234 subjects were finally included and divided into six age groups. The reference intervals of serum AMH in healthy women of childbearing age in different age groups in Shanghai were established. The natural logarithm of serum AMH level and age were fitted by quadratic regression model. Results * The reference interval of serum AMH level was expressed as M(P5-P95), which were 4.76 (0.96-14.17) ng/mL in women aged 19-24 years, 6.03 (1.38-16.56) ng/mL in women aged 25-29 years, 4.30 (0.95-10.73) ng/mL in women aged 30-34 years, 2.40 (0.33-9.27) ng/mL in women aged 35-39 years, 1.04 (0.05-4.00) ng/mL in women aged 40-44 years, and 0.21 (0.01-3.04) ng/ mL in women aged 45-49 years. After logarithmic transformation, serum AMH level and age could well obey the quadratic regression model (R²=0.502). Conclusion * The reference intervals of serum AMH level established for the first time in healthy women of child-bearing age in Shanghai may provide the basis for the evaluation of ovarian reserve function of women of different ages. [ABSTRACT FROM AUTHOR]

To reveal the effects of different fertilization regimes on weed communities in wheat fields under a rice-wheat rotation system, a survey was conducted before wheat harvest in 2014 after a 4-year- long-term recurrent fertilization scheme. Weed species types, density, height and diversity index under different fertilization and straw-returning schemes in wheat fields were studied and complemented with a canonical correspondence analysis on weed community distribution and soil nutrient factors. Twenty weed species were recorded among 36 wheat fields belonging to 19 genera and 11 families. Beckmannia syzigachne, Hemistepta lyrata, Malachium aquaticum and Cnidium monnieri were widely distributed throughout the sampled area. Long-term fertilization appeared to reduce weed species richness and density, particularly for broadleaf weeds, but increased weed height. Diversity and evenness indices of weed communities were lower and dominance indices were higher in fields where chemical fertilizers were applied alone or combined with organic fertilizers, especially, where organic-inorganic compound fertilizer was used, in which it readily caused the outbreak of a dominant species and severe damage. Conversely, diversity and evenness indices of weed communities were higher and dominance indices were lower when the straw was returned to the field combined with chemical or organic fertilizers, in which weed community structures were complex and stable with lower weed density. Under these conditions weeds only caused slight reduction of wheat growth. [ABSTRACT FROM AUTHOR]