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Iterative Bayesian Monte Carlo for nuclear data evaluation

nuclear Science and Techniques 2022年第4期33卷 105-135页

作者： Erwin Alhassan Dimitri Rochman Alexander Vasiliev Mathieu Hursin Arjan JKoning Hakim Ferroukhi Laboratory for Reactor Physics and Thermal-Hydraulics Paul Scherrer Institute5232 VilligenSwitzerland division Large Research Facilities(GFA) Paul Scherrer InstituteVilligenSwitzerland Ecole Polytechnique Federale de Lausanne LausanneSwitzerland nuclear Data Section International Atomic Energy Commission(IAEA)ViennaAustria division of Applied nuclear Physics Department of Physics and AstronomyUppsala UniversityUppsalaSweden

In this work,we explore the use of an iterative Bayesian Monte Carlo(iBMC)method for nuclear data evaluation within a TALYS Evaluated nuclear Data Library(TENDL)*** goal is to probe the model and parameter space of the TALYS code system to find the optimal model and parameter sets that reproduces selected experimental *** method involves the simultaneous variation of many nuclear reaction models as well as their parameters included in the TALYS ***‘best’model set with its parameter set was obtained by comparing model calculations with selected experimental *** experimental data types were used:(1)reaction cross sections,(2)residual production cross sections,and(3)the elastic angular *** improve our fit to experimental data,we update our‘best’parameter set—the file that maximizes the likelihood function—in an iterative *** was determined by monitoring the evolution of the maximum likelihood estimate(MLE)values and was considered reached when the relative change in the MLE for the last two iterations was within 5%.Once the final‘best’file is identified,we infer parameter uncertainties and covariance information to this file by varying model parameters around this *** this way,we ensured that the parameter distributions are centered on our *** proposed method was applied to the evaluation of p+^(59)Co between 1 and 100 ***,the adjusted files were compared with experimental data from the EXFOR database as well as with evaluations from the TENDL-2019,JENDL/He-2007 and JENDL-4.0/HE nuclear data libraries.

关键词： Iterative Bayesian Monte Carlo(iBMC) nuclear reaction models Model parameters Adjustments Bayesian calibration nuclear data TALYS

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Defect types and room temperature ferromagnetism in N-doped rutile TiO_2 single crystals

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Chinese Physics B 2014年第6期23卷 519-523页

作者：秦秀波李东翔李瑞琴张鹏李玉晓王宝义 Key Laboratory of nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences division for nuclear Technology and Application Institute of High Energy Physics Chinese Academy of Sciences School of Mathematics and Physics Anshun University School of Physical Engineering Zhengzhou University

The magnetic properties and defect types of virgin and N-doped TiO2 single crystals are probed by superconducting quantum interference device （SQUID）, X-ray photoelectron spectroscopy （XPS）, and positron annihilation analysis （PAS）. Upon N doping, a twofold enhancement of the saturation magnetization is observed. Apparently, this enhancement is not related to an increase in oxygen vacancy, rather to unpaired 3d electrons in Ti3＋, arising from titanium vacancies and the replacement of O with N atoms in the futile structure. The production of titanium vacancies can enhance the room temperature ferromagnetism （RTFM）, and substitution of O with N is the onset of ferromagnetism by inducing relatively strong ferromagnetic ordering.

关键词： N doping titanium vacancies replacement of 0 with N atoms ferromagnetism

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Mechanical properties of(B_(4)C+Al_(2)O_(3))/Al neutron absorbing materials with various microstructures constructed by hot forging,rolling and extrusion

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Science China(Technological Sciences) 2022年第5期65卷 1206-1209页

作者： ZAN YuNing LI XinNan ZHOU Cong LIU ZhenYu WANG QuanZhao XIAO BoLü MA ZongYi Key Laboratory of nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China nuclear Equipment division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing100840China

Neutron absorbing materials(NAMs)are necessary in the nuclear industry for the storage and transportation of spent *** all the NAMs,B_(4)C/Al composites are widely used because of the specific neutron absorption capacity[1–4].Compared with traditional low-strength functional NAMs such as B_(4)C/1100Al and B_(4)C/6061Al,NAMs with enough high-temperature(350℃)strength are competent for further structural usage and exhibit huge advantages in the dry storage of spent fuel because of heat transfer ability and weight reduction[5].

关键词： absorbing strength enough

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Optimizing the use of open chambers to measure ammonia volatilization in field plots amended with urea

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Pedosphere 2021年第2期31卷 243-254页

作者： Márcio R.MARTINS Leonardo F.SARKIS Selenobaldo A.C.SANT’ANNA Camila A.SANTOS Karla E.ARAUJO Ricardo C.SANTOS Ednaldo S.ARAÚJO Bruno J.R.ALVES Claudia P.JANTALIA Robert M.BODDEY Mohammad ZAMAN Segundo URQUIAGA Embrapa Agrobiology Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Federal Rural University of Rio de Janeiro(UFRRJ) Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Agroscope Research Division Agroecology and EnvironmentClimate and Agriculture GroupReckenholzstrasse 191Zurich 8046(Switzerland) Soil and Water Management&Crop Nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureP.O.Box 100Vienna A-1400(Austria)

Measuring ammonia(NH_(3))volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen(N)losses in *** small area of chambers used for NH_(3)volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are *** aims were:i)to investigate the effect of using multiple open chambers on the variability in the measurement of NH_(3)volatilization in urea-amended field plots and ii)to define the critical period of NH_(3)-N losses during which the concentration of sampling effort is capable of reducing *** use of only one chamber covering 0.015%of the plot(51.84 m^(2))generates a value of NH_(3)-N loss within an expected margin of error of 30%around the true *** reduce the error margin by half(15%),3–7 chambers were required with a mean of 5 chambers per *** the sampling efforts in the first two weeks after urea application,which is usually the most critical period of N losses and associated errors,represents an efficient strategy to lessen uncertainty in the measurements of NH_(3)*** strategy enhances the power of detection of NH_(3)-N loss abatement in field experiments using chambers.

关键词： chamber method experimental error gas emission low-cost chamber nitrogen cycling nitrogen loss soil variability

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Spectroscopy of Low-lying States in Odd-Z Odd-A Nuclei Beyond Lead

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原子核物理评论 2016年第2期33卷 141-145页

作者： U.Jakobsson J.Uusitalo K.Auranen H.Badran B.Cederwall D.M.Cox T.Grahn P.T.Greenlees R.Julin S.Juutinen A.Herzán J.Konki M.Leino M.Mallaburn J.Pakarinen P.Papadakis J.Partanen P.Rahkila M.Sandzelius J.Sarén C.Scholey J.Sorri S.Stolze KTH The Division of Nuclear PhysicsAlba Nova University Center University of Jyvaskyla Department of Physics

Low-lying states in odd-Z odd-mass nuclei at the proton drip-line beyond lead have recently been studied through fusion-evaporation reactions using a gas-filled recoil separator. Isomeric 1/2+and13/2+states have been observed in odd-mass astatine and francium nuclei. The systematic behaviour of the level energies of these states have been studied and a similarity between the 1/2+state in astatine and francium has been found. Furthermore, the 13/2+state has been observed in the francium nuclei with an oblate behaviour suggesting a coupling of the i13/2proton to the 2p- 2h intruder excitation.

关键词： nuclear spectroscopy isomeric states Z > 82

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A simple and easy method to measure ammonia volatilization:Accuracy under field conditions

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Pedosphere 2021年第2期31卷 255-264页

作者： Márcio R.MARTINS Leonardo F.SARKIS Roni F.GUARESCHI Camila A.SANTOS Selenobaldo A.C.SANT’ANNA Mohammad ZAMAN Claudia P.JANTALIA Bruno J.R.ALVES Robert M.BODDEY Ednaldo S.ARAÚJO Segundo URQUIAGA Embrapa Agrobiology Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Agroscope Research Division Agroecology and EnvironmentClimate and Agriculture GroupReckenholzstrasse 191Zurich 8046(Switzerland) Federal Rural University of Rio de Janeiro(UFRRJ) Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Soil and Water Management&Crop Nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureP.O.Box 100Vienna A-1400(Austria)

Field studies on soil ammonia(NH_(3))volatilization are restricted in many countries owing to the high costs commonly demanded for accurate *** assessed the accuracy of a simple,open chamber design to capture NH_(3)under field conditions,as affected by different chamber placement ***-15 N was surface applied to lysimeters installed in the spaces between maize *** chambers made from plastic bottles were installed on each lysimeter with variations in i)N rates(3,8,13,and 18 g m^(-2)),ii)the height of the chamber above the soil surface(0,5,and 10 mm),and iii)chamber relocation(static ***).Reference lysimeters without chambers were used to measure NH_(3)losses by^(15)*** of NH_(3)-N accounted for more than 50%of the applied *** of the chambers had no impact on their NH_(3)-trapping efficiencies,proving to be an unnecessary *** in the height of the chambers above the soil surface affected the capture of NH_(3),but the results still maintained high linearity with the NH_(3)losses quantified by the reference method(R^(2)>0.98).When the same placement scheme used in the introductory study describing the chamber was utilized(static and touching the soil surface),we found a trapping efficiency of 60%,which was very similar to that(57%)obtained in the previous *** results show that this simple,open chamber design can be used with satisfactory accuracy under field conditions,provided that simple,standardized procedures are warranted.

关键词： ammonia collector chamber method field sampler gas emission low-cost chamber nitrogen cycling

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Effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony

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Chinese Medical Journal 2004年第4期117卷 516-520页

作者：支力大华伟张澍史蓉芳王方正陈新 division of Clinical Electrophysiology Department of nuclear Medicine

Background Right ventricular apical pacing has been reported to reduce cardiac performance. But there are few reports on the effects of dual chamber (DDD) pacing on cardiac function compared to sinus rhythm. In this study, we evaluated the effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony using equilibrium radionuclide angiography. Methods Ten patients implanted with a right atrial and ventricular DDD pacemaker underwent equilibrium radionuclide angiography. The scintigraphic data were obtained during sinus rhythm and pacing rhythm. Cardiac function parameters were obtained semimanually. Phase analysis was used to study the ventricular activation sequence and ventricular synchrony. Results The left ventricular 1/3 ejection fraction decreased significantly during pacing compared with that during sinus rhythm[ (23.4 +/- 6.1)% vs (27.7 +/- 4.5) %, P = 0.01]. Regional ejection fraction also decreased during pacing, although the difference was not statistically significant. Phase analysis showed that the right ventricle was activated earlier than the left ventricle during pacing, and that the phase shift was significantly greater during pacing than that during sinus rhythm[ 64.13degrees +/- 16.80degrees vs 52.88degrees +/- 9.26degrees, P = 0. 007 ]. The activation of both ventricles occurred simultaneously during sinus rhythm, with the activation sequence from proximal septum or base of left ventricle to apex. The earliest activation during pacing occurred at the right ventricular apex, and subsequently spread to the base and left ventricle. Conclusion Right atrial and ventricular DDD pacing impairs left ventricular systolic function and ventricular synchrony.

关键词： equilibrium radionuclide angiography · phase analysis · cardiac pacing · cardiac function

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Effects of electron radiation on commercial power MOSFET with buck converter application

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nuclear Science and Techniques 2017年第3期28卷 30-34页

作者： Sheik Fareed Ookar Abubakkar Nor Farahidah Zabah Yusof Abdullah Dhiyauddin Ahmad Fauzi Norasmahan Muridan Nurul Fadzlin Hasbullah Department of Electrical and Computer Engineering International Islamic University Kuala Lumpur 53100Malaysia Industrial Technology division Agency Nuclear MalaysiaKuala Lumpur 43000 Malaysia

Microelectronic power converters such as buck and boost converter are required to be tolerant to radiations including electron radiation. This paper examines electron radiation effects on the Ⅰ-Ⅴ characteristics of VDMOSFET and its corresponding effects in buck converter. Analysis of the electrical characteristics shows that after irradiation the threshold voltage and drain current for all VDMOSFETs degraded more than two orders of magnitude. The impact of this electrical degradation has been investigated in an application of typical buck converter circuit. The buck converter with n-channel switching transistor shows that after irradiation its output voltage increased with the drain current in the n-channel ZVN4424 A VDMOSFET, while the buck converter with p-channel switching transistor shows its output voltage decreased with the drain current in the p-channel ZVP4424 A VDMOSFET after irradiation.

关键词： VDMOSFET I–V characteristics Drain current Buck converter Electron radiation

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Monte Carlo Study of CO-NO Catalytic Surface Reaction Including CO-CO Repulsion

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Chinese Physics Letters 2006年第4期23卷 1034-1037页

作者： Waqar Ahmad Musa Kaleem Baloach Physics Research division Pakistan Institute of Nuclear Science and Technology PO Nilore Islamabad Pakista Department of Chemistry Gomal University D.I. Khan Pakistan

The CO-NO reaction on a catalytic surface is studied by using Langmuir-Hinshclwood thermal mechanism with Monte Carlo computer simulation. In this model, a novel concept of CO CO repulsion is introduced, which has experimental evidence due to the formation of dipoles when these molecules are chemisorbed on the surface. The system is investigated by applying two approaches of NO dissociation. In the first ***, NO always decomposes into N and O before adsorption on the surface, In the second case, NO adsorbs on the surface molecularly and then dissociates into N and O if a vacancy is present in its adjacent neighbourhood. The steady state reactive window （i.e. the continuous production of CO2 and N2） is obtained only with the diffusion of N-atoms on the surface, which extends with CO-CO repulsion in the first, case. Itowever, in the second case, reactive window is obtained with CO-CO repulsion alone, The reactive window width in this case is reasonably large. The first-order phase transition is eliminated in both the cases with CO-CO repulsion.

关键词： KINETIC PHASE-TRANSITIONS SQUARE LATTICE HEXAGONAL SURFACES REACTIONMODEL NITRIC-OXIDE SIMULATION MECHANISM

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Capsaicin(CAP) exerts a protective effect against ethanol-induced oxidative gastric mucosal injury by modulating the chemokine receptor 4 (CCR4)/Src/p47phox signaling pathway both in vitro and in vivo

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Chinese Journal of Natural Medicines 2025年第2期23卷 191-202页

作者： Zhiru Yang Haolin Guo Pengfei Zhang Kairui Liu Junli Ba Xue Bai Shiti Shama Bo Zhang Xiaoning Gao Jun Kang School of Life Sciences Tianjin University School of Traditional Chinese Medicine Beijing University of Chinese Medicine Tianjin Pharmaceutical and Cosmetic Evaluation and Inspection Center Institute for TCM-X MOE Key Laboratory of Bioinformatics Bioinformatics Division BNRist Department of Automation Tsinghua University Institute of Biomedical Research Henan Academy of Sciences

Ethanol(EtOH) is a common trigger for gastric mucosal diseases, and mitigating oxidative stress is essential for attenuating gastric mucosal damage. Capsaicin(CAP) has been identified as a potential agent to counteract oxidative damage in the gastric mucosa; however, its precise mechanism remains unclear. This study demonstrates that CAP alleviates EtOH-induced gastric mucosal injuries through two primary pathways: by suppressing the chemokine receptor 4(CCR4)/Src/p47phox axis, thereby reducing oxidative stress, and by inhibiting the phosphorylation and nuclear translocation of nuclear factor-κB p65(NF-κB) p65, resulting in diminished inflammatory responses. These findings elucidate the mechanistic pathways of CAP and provide a theoretical foundation for its potential therapeutic application in the treatment of gastric mucosal injuries.

关键词： Capsaicin Chemokine signaling Gastric mucosal damage NF-κB p65

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