Improved mass relations of mirror nuclei

In this study,we revisit the previous mass relations of mirror nuclei by considering 1/N-and 1/Z-dependent terms and the shell effect across a shell.The root-mean-squared deviation is 66 keV for 116 nuclei with neutron number N≥10,as com-pared with experimental data compiled in the AME2020 database.The predicted mass excesses of 173 proton-rich nuclei,including 98 unknown nuclei,are tabulated in the Supplemental Material herein with competitive accuracy.

The breaking of spin symmetry in the single-particle resonances in deformed nuclei

The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus structures.In this study,we solve the Dirac equation from the relativistic mean field (RMF) in complex momentum representation.We investigated SS and its breaking in single-particle resonant states within deformed nuclei,with a focus on the illustrative nucleus168Er.This was the initial discovery of a resonant spin doublet in a deformed nucleus,with the expectation of the SS approaching the continuum threshold.With increasing single-particle energy,the splitting of the resonant spin doublets widened significantly.This escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy levels increase.We also analyzed the width of the resonant states,showing that lower orbital angular momentum resonances possess shorter decay times and that SS is preserved within broad resonant doublets,as opposed to narrow resonant doublets.Comparing the radial density of the upper components for the bound-state and resonant-state doublets,it becomes evident that while SS is well-preserved in the bound states,it deteriorates in the resonant states.The impact of nuclear deformation (β_(2)) on SS was examined,demonstrating that an increase in β_(2) resulted in higher energy and width splitting in the resonant spin doublets,which is attributed to increased component mixing.Furthermore,the sensitivity of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in SS.This study provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay with the nuclear structure,thereby advancing our understanding of SS in the resonance state.

Systematic study on heavy-particle radioactivity of superheavy nuclei ^(297–300)119

In the current study,we examined every possible cluster-daughter combination in the heavy-particle decay of isotopes ^(297-300)119 and computed the decay half-lives using the modified generalized liquid drop model(MGLDM)with the preformation factor depending on the disintegration energy.The predicted half-life of every heavy cluster(Z_(C)≥32)was within the experimentally observable limits.These results aligned with the predictions of Poenaru et al.[Phys.Rev.Lett.107,062503(2011)]that superheavy nuclei(SHN)with Z>110 will release heavy particles with a penetrability comparable to or greater than theα-decay.The half-lives predicted using the MGLDM for clusters^(89)Rb,^(91)Rb,and^(92)Rb from parents^(297)119,^(299)119,and^(300)119,respectively,agreed with the predictions of Poenaru et al.[Eur.Phys.J.A 54,14(2018)].It was found that the isotopes of heavy clusters Kr,Rb,Sr,Pa,In,and Cd had half-lives comparable to theαhalf-life;and isotopes of clusters I,Xe,and Cs had the minimum half-life(10^(-14)s).These observations revealed the role of the shell closure(Z=82,N=82,and N=126)of the cluster and daughter nuclei in heavy-cluster radioactivity.We predicted that isotope ^(297,299)119 decayed by 4αdecay chains and isotope^(300)119 decayed by 6αdecay chains,while^(298)119 decayed by continuousαdecay chains.The predicted half-lives and modes of decay of the nuclei in the decay chains of^(297-300)119 agreed with the experimental data,proving the reliability of our calculations.The present study determined the most favorable heavy-cluster emissions from these nuclei and provided suitable projectile-target combinations for their synthesis.

On joint analysing XMM-NuSTAR spectra of active galactic nuclei

A recently released XMM-Newton note revealed a significant calibration issue between nuclear spectroscopic telescope array(NuSTAR)and XMM-Newton European Photon Imaging Camera(EPIC)and provided an empirical correction to the EPIC effective area.To quantify the bias caused by the calibration issue in the joint analysis of XMM-NuSTAR spectra and verify the effectiveness of the correction,in this work,we perform joint-fitting of the NuSTAR and EPIC-pn spectra for a large sample of 104 observation pairs of 44 X-ray bright active galactic nuclei(AGN).The spectra were extracted after requiring perfect simultaneity between the XMM-Newton and NuSTAR exposures(merging good time intervals(GTIs)from two missions)to avoid bias due to the rapid spectral variability of the AGN.Before the correction,the EPIC-pn spectra are systematically harder than the corresponding NuSTAR spectra by■subsequently yielding significantly underestimated cutoff energy E_(cut)and the strength of reflection component R when performing joint-fitting.We confirm that the correction is highly effective and can commendably erase the discrepancy in best-fitΓ,E_(cut),and R.We thus urge the community to apply the correction when joint-fitting XMM-NuSTAR spectra,but note that the correction is limited to 3–12 keV and therefore not applicable when the soft X-ray band data are included.Besides,we show that as merging GTIs from two missions would cause severe loss of NuSTAR net exposure time,in many cases,joint-fitting yields no advantage compared with utilizing NuSTAR data alone.Finally,We present a technical note on filtering periods of high background flares for XMM-Newton EPIC-pn exposures in the small window(SW)mode.

Opportunities for production and property research of neutron-rich nuclei around N=126 at HIAF

The study of nuclide production and its properties in the N=126 neutron-rich region is prevalent in nuclear physics and astrophysics research.The upcoming High-energy FRagment Separator(HFRS)at the High-Intensity heavy-ion Accelerator Facility(HIAF),an in-flight separator at relativistic energies,is characterized by high beam intensity,large ion-optical acceptance,high magnetic rigidity,and high momentum resolution power.This provides an opportunity to study the production and properties of neutron-rich nuclei around N=126.In this paper,an experimental scheme is proposed to produce neutron-rich nuclei around N=126 and simultaneously measure their mass and lifetime based on the HFRS separator;the feasibility of this scheme is evaluated through simulations.The results show that under the high-resolution optical mode,many new neutron-rich nuclei approaching the r-process abundance peak around A=195 can be produced for the first time,and many nuclei with unknown masses and lifetimes can be produced with high statistics.Using the time-of-flight corrected by the measured dispersive position and energy loss information,the cocktails produced from 208 Pb fragmentation can be unambiguously identified.Moreover,the masses of some neutron-rich nuclei near N=126 can be measured with high precision using the time-of-flight magnetic rigidity technique.This indicates that the HIAF-HFRS facility has the potential for the production and property research of neutron-rich nuclei around N=126,which is of great significance for expanding the chart of nuclides,developing nuclear theories,and understanding the origin of heavy elements in the universe.

RETRACTED: Nuclear Structure Study of Odd-Odd Yttrium Nuclei within Interacting-Boson Fermi-Fermion Model (IBFFM)

Short Retraction NoticeThe paper does not meet the standards of "Journal of Applied Mathematics and Physics". This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused.Editor guiding this retraction: Prof. Wen-Xiu Ma (EiC of JAMP)The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED".

Constraining nuclear symmetry energy with the charge radii of mirror-pair nuclei

The nuclear charge radius plays a vital role in determining the equation of state of isospin asymmetric nuclear matter.Based on the correlation between the differences in charge radii of mirror-partner nuclei and the slope parameter(L)of symmetry energy at the nuclear saturation density,an analysis of the calibrated slope parameter L was performed in finite nuclei.In this study,relativistic and nonrelativistic energy density functionals were employed to constrain the nuclear symmetry energy through the available databases of the mirror-pair nuclei^(36)Ca–^(36)S,^(38)Ca–^(38)Ar,and ^(54)Ni–^(54)Fe.The deduced nuclear symmetry energy was located in the range 29.89–31.85 MeV,and L of the symmetry energy essentially covered the range 22.50–51.55 MeV at the saturation density.Moreover,the extracted L_(s) at the sensitivity density p_(s)=0.10 fm^(-3) was located in the interval range 30.52–39.76 MeV.

A New Simulation Model for Recoil Analysis of Deep-Water Drilling Risers After Emergency Disconnection

The recoil response of a deep-water drilling riser following an ED(Emergency Disconnection)scenario is a transient and sensitive process.The recoiling displacement of the riser is the resultant of recoil motion and axial stretch.How-ever,it is typically represented by one variable in recoil simulations.As axial deformation is quite small compared with axial motion in the recoil process,it inevitably introduces numerical errors(i.e.,a large number annihilating a small number).Thus,it is hard to perform a quantitative analysis of axial deformation,although a consensus initial deformation is essential for recoil dynamics.Moreover,the triggered axial natural modes have never been examined before.In this study,the recoil response is decomposed into two parts:recoil motion and axial deformation,and a novel model is developed by Galerkin method.It has demonstrated that the initial stretch has a significant effect at the initial stage in recoil.The existing models underestimate the effects of axial deformation.The new model can capture information of triggered natural modes and figure out the modes undergoing dynamic compression.This study can be beneficial to overpull setting,determination of ED time and anti-recoil control optimization.

Temperature influences of the recoil characteristics for aluminum honeycomb buffer in the tether-net launcher

Fluctuations in outer space's temperature would affect the spacecraft's regular operation.This paper aims to study the temperature influences of the aluminum honeycomb buffer in the tether-net launcher.Firstly,a buffer structure was designed to attenuate the pyroshock generated by the pyrotechnic device.Secondly,the mechanical properties of aluminum honeycomb at different temperatures were obtained through quasi-static compression experiments.Then,the internal ballistic responses of the launcher were gained by the closed bomb tests and the equivalent classical interior ballistic model.Finally,the recoil performance of the launcher with aluminum honeycomb buffer at different temperatures was studied.It is revealed that the aluminum honeycomb crushing force gradually decreases with the temperature increases.The peak pressure,burning rate coefficient and velocity increase while the peak time decreases with the temperature increase for the interior ballistics.For the launcher recoil responses,the average launch recoil decreases if the aluminum honeycomb doesn't enter the dense stage.The impact acceleration,projectile velocity and displacement increase as the temperature increase.The paper spotlights the temperature's influence on the recoil characteristics of the aluminum honeycomb buffer,which provides a new idea for buffering technology of pyrotechnic devices in a complex space environment.

Nuclei Segmentation in Histopathology Images Using Structure-Preserving Color Normalization Based Ensemble Deep Learning Frameworks

This paper presents a novel computerized technique for the segmentation of nuclei in hematoxylin and eosin(H&E)stained histopathology images.The purpose of this study is to overcome the challenges faced in automated nuclei segmentation due to the diversity of nuclei structures that arise from differences in tissue types and staining protocols,as well as the segmentation of variable-sized and overlapping nuclei.To this extent,the approach proposed in this study uses an ensemble of the UNet architecture with various Convolutional Neural Networks(CNN)architectures as encoder backbones,along with stain normalization and test time augmentation,to improve segmentation accuracy.Additionally,this paper employs a Structure-Preserving Color Normalization(SPCN)technique as a preprocessing step for stain normalization.The proposed model was trained and tested on both single-organ and multi-organ datasets,yielding an F1 score of 84.11%,mean Intersection over Union(IoU)of 81.67%,dice score of 84.11%,accuracy of 92.58%and precision of 83.78%on the multi-organ dataset,and an F1 score of 87.04%,mean IoU of 86.66%,dice score of 87.04%,accuracy of 96.69%and precision of 87.57%on the single-organ dataset.These findings demonstrate that the proposed model ensemble coupled with the right pre-processing and post-processing techniques enhances nuclei segmentation capabilities.

Stability of Nuclei Based on the New Proton and Neutron Model

According to the new proton and neutron nuclear picture described earlier, the structure of the nucleus will also be given a new interpretation. The role of the delocalized electrons detached from the outer shell of neutrons is shown in the binding energy value of the nucleus. It is pointed out that the spatial arrangement of nucleons is also very important for the stability of nuclei according to the analyzation of the magic numbers from a geometric point of view.

Cyclic feeding regime may delay aging in animals by enhancing the hepatocytes nuclei structure

Background:The liver is fundamental for keeping up the entire body’s homeostasis.The liver hepatocytes have been shown to undergo genomic instability with aging.The stability of the hepatocytes depends on its nuclear architecture.Calorie restriction has been shown to extend life-span favorably and this may be through the reorganization of the nuclear structure.Objective:To study the effect of cyclic feeding regime on the chromatin assembly anchored to the nuclear membrane scaffold of rat models hepatocytes nuclei.Method:Rats models underwent cyclic feeding regime,after which nuclei were isolated;then,we investigated the chromatin decondensation and nuclear membrane disintegration of the hepatocytes using fluorescence imaging methods.Results:In 60 seconds,protease decondensed the chromatin and disintegrated the nuclear membrane structure of controls.After the first fasting,the time increased to 145 seconds in 3-month-old rats.The first refeeding increased the time to 156 seconds with a further rise to 340 seconds following the second fasting,then dropped to 116 seconds by the second refeeding.20 months old rats showed 186 seconds increase in the time of chromatin decondensation and nuclear membrane disintegration after the first fasting,with a decrease to 140 seconds observed after first refeeding.The second fasting increased the time to 165 seconds,which then slightly decreased to 163 seconds after the second refeeding.Conclusion:These results show that intermittent fasting may have acted on chromatin histone interactions and the structural lamin networks of the nuclear membranes in bringing about nuclear stability,which is essential for normal cellular function.

氨基质子转移成像对帕金森患者小脑微结构代谢变化的初步探究

目的 探讨利用MR氨基质子转移成像(amide proton transfer,APT)和弥散张量成像(diffusion tensor image,DTI)对帕金森病(parkinson’s disease,PD)患者小脑微结构变化的临床应用价值。方法 选取我院46例PD患者为PD组进行APT和DTI检查,并选取48例健康者作为对照组。根据APT和DTI分别对感兴趣区测出MTR值和FA值,并分析组间差异。以t检验评估其参数对PD是否有一定诊断价值。结果 PD组小脑髓质的FA值和ADC值与对照组相比FA值减低,ADC值增高,差异有统计学意义(P<0.001);PD组齿状核FA值低于对照组,MTR值低于对照组,差异有统计学意义(P<0.001)。PD组黑质FA值低于对照组,MTR值低于对照组,差异有统计学意义(P<0.001)。在ROC分析中齿状核与黑质在MTR值对PD具有一定的诊断准确性(P<0.05),小脑髓质、齿状核与黑质FA值对PD具有一定的诊断准确性(P<0.05)。结论 APT可以反映PD患者小脑微结构代谢的变化,其参考值可以作为PD患者评估指标。

小脑齿状核脑深部电刺激术对脑卒中后运动功能的改善作用

脑卒中可以导致长期运动障碍,降低生活质量。尽管传统康复治疗取得的进展为患者带来曙光,仍有众多患者面临康复治疗效果有限的问题。神经调控技术即显示出突破性治疗潜力。本文旨在概述脑卒中后神经可塑性机制,探究小脑齿状核脑深部电刺激术改善脑卒中后运动功能的作用机制、总结研究进展,以为临床实践提供科学依据及新的治疗视角。

An Efficient Method of Nuclei Extraction in Cotton

[Objective] The experiment aimed to study an efficient method of Nuclei extraction of cotton and provided technical support for constructing large-insert genomic library and sequencing complete genome. [Method] The cotton cotyledons germinated in dark moisture chamber for one week were chopped with a sharp sterile scalpel in a Petri dish which contained ice-cold nucleus isolation buffer (10 mmol/L MgSO4, 5 mmol/L KCl, 0.5 mmol/L HEPES, 1 mg/ml DTT, 0.25% Triton X-100 and 2% PVP40), then the nuclei were collected after selected through 100, 50 and 30 μm nylon meshes and centrifugation. Meanwhile, the tender leaves and cotyledons with different germination time in dark were treated by grinding method and sharp scalpel method. [Result] The chopping with a sharp scalpel method was very simple and rapid, which did not need grind and mercaptoethanol treatment and the successful extraction rate was 100%.[Conclusion] An efficient method of nuclei extraction of cotton with simple, high efficiency, rapid reaction and poison free were established.

适应火工装置冲击环境的铝蜂窝缓冲特性研究

针对火工装置发射过程中对卫星平台产生的冲击,设计了一种基于铝蜂窝的新型空间发射缓冲结构,通过火药密爆试验和铝蜂窝准静态压溃试验分别建立了空间火工发射装置内弹道模型和铝蜂窝压溃模型,在此基础上建立了发射后坐动力学模型,并重点研究了火药药量和铝蜂窝内径对发射后坐特性的影响。研究结果表明:当火药药量增大0.3 g,后坐力平均值增大了1.95%,牵引体发射速度增大了5.10%,后坐位移增大了7.64%,后坐力持续时间减小10.3%。当铝蜂窝内径从148 mm分别减小1 mm和2 mm时,后坐力平均值增大了4.06%和9.08%,牵引体发射速度增大了0.22%和0.54%,后坐位移增大了3.38%和15.24%。同时以上参数的合理选择可以有效降低发射后坐力并保证牵引体的发射性能。

后坐载荷施加方式对火炮动力学仿真影响研究

在火炮研发的初期阶段,进行总体方案论证对于确保设计的可靠性和安全性至关重要。考虑到研究条件的不同,利用动力学仿真软件对某大口径履带式自行火炮的发射过程稳定性进行了精确分析,在0°射角的标准射击姿态下模拟了无驻锄支撑2种情形,探讨了基于理论设计公式加载、基于解算曲线的载荷加载以及基于后坐制动图的载荷加载等3种不同后坐载荷施加方式对火炮动力学仿真影响。此外,还对未配备反后坐装置的火炮模型进行了仿真分析。研究通过将仿真结果与高速摄像捕获的实际射击试验数据对比,深入分析了不同模型的误差幅度及其成因。研究成果可以有效提升设计人员对动力学仿真结果误差范围的预测精度,为大口径火炮设计提供了重要的参考依据。

系统不确定的深海钻井立管解脱反冲智能控制

深海钻井立管系统紧急解脱后的反冲控制是深海油气钻探中的必备技术,但系统动力参数在多方面具有不确定性与难测性,给实际反冲控制带来了严峻挑战.建立系统模型不确定条件下的立管反冲智能自适应控制方法,通过反冲控制名义状态空间方程与闭环系统稳定性推导考虑模型不确定的修正控制输入,采用径向基(RBF)神经网络逼近模型不确定部分并选取满足李雅普诺夫(Lyapunov)稳定的权值自适应律,实现控制输入中对不确定部分的动态补偿.结果表明:该方法适用于实际反冲控制阀有调控速度限制的情况;张紧器刚度、阻尼、钻井液下泄摩擦力及立管浮力载荷等不确定性对反冲动力响应及控制效果均有一定影响;无论系统参数是否精确,经过RBF自适应控制后都降低了反冲初期振荡高度且降低了反冲触底风险.研究成果可有效解决工程背景下缺乏准确系统参数的立管反冲控制难题.

Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental results.The synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 d.The influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in detail.The reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

垂直弹射系统中缓冲及反后坐效应的建模方法

针对垂直弹射过程中,由缓冲以及弹射后坐引发的对发射性能与阵地产生的负面影响问题,从缓冲吸能角度,提出按缓冲器的塑性应变能-压缩量关系曲线拟合并求导解算缓冲力-压缩量关系模型的方法,有效规避了缓冲力波动所造成的拟合漂移问题,并据此构造了模拟缓冲器的线弹性-塑性弹簧模型;依据弹射试验数据,反演了反后坐效应的动态数据,据此构造了模拟反后坐效应的非线性粘弹性-塑性弹簧模型;通过力元、状态变量及牛顿迭代法的有机结合,在动力学模型中实现了上述二模型的高效解算。仿真结果表明:两模型计算稳定高效且缓冲特性与有限元仿真结果高度吻合、反后坐效应和试验数据符合良好,这验证了数据处理方法的有效性和建模方法的可信性,为后续含缓冲和反后坐效应的弹射动力学仿真提供了一种稳定而又可信的建模思路。