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The concept of oscillator problems finds its indispensable presence in numerous dynamical systems. Machine learning techniques for handling dynamical systems is a challenging and rapidly expanding field of research. In this regard, a machine learning approach, namely Symplectic Artificial Neural Network model, has been used for handling the non-linear systems arising in dusty plasma models. The primary objective of this article is to investigate, the dynamics of Van der Pol-Mathieu-Duffing Oscillator problems for different excitation functions using the meshfree Symplectic Artificial Neural Network algorithm. The numerical simulations and graphical representations are carried out to establish the accuracy of the presented algorithm. Also, the obtained simulation results are compared with the existing numerical solutions. In addition, the statistical assessment studies at various testing points confirm an excellent agreement between the present simulation results and the existing results. [ABSTRACT FROM AUTHOR]

The excitation function of the charged particle-induced reaction plays an important role in basic nuclear physics research, nuclear engineering design and nuclear technology applications, and which is also essential input information required in areas such as accelerator shielding and fusion reactor design, space radiation effects, radiation therapy and biomedical radioisotope production. In the field of tumor therapy, 211At is ideal targeted therapeutic nuclide for generating α-rays, which is prepared by α-particle bombardment of a bismuth target, and therefore the large-scale production of 211At nuclide relies on the information related to the data of 209Bi(α,2n)211At reaction excitation function and the thick target yield of the 211At nuclide. The production of 211At nuclide is accompanied with the production of 210At nuclide (the decaying substrates are highly toxic 210Po nuclides), and it is also necessary to analyze the data of excitation function for the 209Bi(α,3n)210At reaction and the thick target yield of the 210At nuclide for determining whether the prepared 211At product meets the requirements of the subsequent drug labelling. Based on the above background, the experimental data of 209Bi(α,2n)211At and 209Bi(α,3n)210At reaction excitation function in the Experimental Nuclear Reaction Database (EXFOR) were compiled and analyzed. However, there are still divergency in the experimental data of the reaction excitation functions, especially for the 209Bi(α,3n)210At reaction, and the analyzed available experimental data are discontinuous in some energy region. For providing the reasonable and continuous data of the above two reactions, the relevant theoretical calculations were carried out based on the EMPIRE code. Through the comparison between the experimental data and the EMPIRE calculation results, the reasonable forms of optical potential parameters and level density parameters are chosen. With the enhanced generalized superuid model (EGSM) for level density in the EMPIRE code, the evolution data of the excitation functions of the above two reactions are obtained, and both of them are in general agreement with the analyzed experimental data. Based on the evolution data of 209Bi(α,2n)211At reaction excitation function, the thick target yield of the medical radioisotope 211At was calculated, and it is in good agreement with the related experimental data. Besides, the thick target yield of 210At (the parent nucleus of the highly toxic nuclide 210Po) was also studied. And the results show that the thick target yield ratio of 210At to 211At is less than 10-5 at Eα

This study used the theoretical nuclear model codes COMPLET and TALYS-1.95 to make theoretical predictions of the medically important production cross-sections for Chromium-51, Manganese-54, Iron-59, Cobalt-59 and Cobalt-60 radionuclides produced in the interaction of alpha- projectile with Cobalt-59 target ≈ 25 – 172 MeV alpha-energies. The results were compared with the measured values in the EXFOR data library. Pearson's correlation coefficient indicates a strong and positive correlation between the predicted and the previously measured medically important production cross-sections for Chromium-51, Manganese-54, Iron-59, Cobalt-59, and Cobalt-60 radionuclides. Further, the results showed that except for Chromium-51, the COMPLET code predicts more successful outcomes than the TALYS-1.95.

Cross sections of the 86Sr(p,3n)84mY, 86Sr(p,αn)82mRb, and 86Sr(p,x)85gSr reactions were measured from their respective thresholds up to 16.2 MeV and from 23.0 to 44.1 MeV at FZJ, and from 14.3 to 24.5 MeV at LBNL, using 96.4% enriched 86SrCO3 as target material. Thin targets prepared by sedimentation were irradiated with protons in a stacked-form, and the induced radioactivity was measured by high-resolution γ-ray spectrometry. Nuclear model calculations based on the code TALYS reproduced our experimental cross section data well. From the excitation functions, the integral yields of the above three radionuclides were calculated. The yield of 85gSr via the natSr(n,γ) process was also measured using the TRIGA Mark-II reactor at AERE, Savar. A comparison of the reactor and cyclotron production of carrier-added 85gSr is given. The production possibilities of the three investigated radionuclides in no-carrier-added forms at a 30 MeV cyclotron via new routes are discussed.

Bearing is the most basic component of motor, and prone to failure. Bearing fault diagnosis is paramount for improving the reliability and safety in motor‐drive systems. Therefore, convolutional neural network (CNN) is proposed with Logistic chaotic map and its corresponding fault diagnosis approach, which can effectively advance the accuracy of bearing fault diagnosis. Specifically, the Logistic chaotic map and Sigmoid function are combined into a non‐monotonic excitation function, which is employed to the full connection layer of the CNN. The proposed chaotic CNN can solve two issues that the conventional neural network inclines to get the local minimum value and the gradient of Sigmoid excitation function disappears. It is applied to fault data from the center of Western Reserve University and from the American Society for Mechanical Failure Prevention technology (in noiseless and noisy conditions). The results indicate the diagnosis accuracy of the algorithm outperforms other classical bearing diagnosis algorithms. Moreover, the chaotic CNN exhibits better anti‐noise performance. [ABSTRACT FROM AUTHOR]

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Excitation functions for the formation of the radionuclides 51Cr, 52Mn and 54Mn via deuteron-induced activation of natural iron were measured up to deuteron energies of 35 MeV. The available experimental databases of the reaction products 51Cr, 52Mn and 54Mn were extended and compared with the nuclear model calculations using the TALYS code. The model calculations reproduce our measured data after a careful choice of the input model parameters. Some information obtained on competition between the emission of multinucleons and a bound α-particle. [ABSTRACT FROM AUTHOR]

This study focuses on the theoretical calculations of neutron-induced reaction cross-sections on several stable isotopes of cadmium within the energy range of 13–15 MeV. The nuclei produced in this process include 105Cd, 106Ag, 107Cd, 109Cd, and 110Ag. To calculate the reaction cross-sections for specific reactions such as 106Cd (n, 2n) 105Cd, 106Cd (n, p) 106Ag, 108Cd (n, 2n) 107Cd, 110Cd (n, 2n) 109Cd, and 110Cd (n, p) 110Ag, we employed the Alice 91-based computer code. The calculated results were then compared and tabulated alongside experimental data obtained from the International Atomic Energy Agency (IAEA) data source, EXFOR library. Additionally, we plotted the reaction cross-sections against neutron energy (excitation function) for each reaction channel. Our findings demonstrate a strong agreement between the calculated and experimental data within the specified neutron energy range. Furthermore, we introduced several statistical parameters to assess the fitting quality between the theoretically calculated and experimentally measured reaction cross-section values.

Excitation functions of the reactions 27Al(d,αp)24Na, 27Al(d,2p)27Mg and 27Al(d,p)28Al were measured by the activation technique up to deuteron energies of 37 MeV. The available experimental databases of the reaction products 27Mg and 28Al were extended and compared with the nuclear model calculations based on the code TALYS-1.8. Our measured data are reproduced well by the model calculations after adjustment of a few free input parameters. The cross-section ratio of the (d,αp) to (d,2p) process as a function of projectile energy was deduced from the measured data, and the result is interpreted in terms of competition between a proton and an α-particle emission.

In this paper, semantic segmentation based on a convolutional neural network is used to guide the image color restoration process. In order to avoid the problem of content mismatch, higher-order features are first extracted from the basic dimensions of the input image, and the convolutional operation is done on the feature map by the excitation function. Then the network parameters are optimized and updated by the backpropagation algorithm to minimize the error between the prediction result and the real result. Finally, in image processing, the dilated convolution technique is introduced to perform noise reduction on the semantic segmented image pixels to optimize the restoration quality. In order to prove the effectiveness of the method in this paper, an experimental analysis of the method is conducted. The experimental results show that the peak signal-to-noise ratio of the model proposed in this paper is higher than 42.986db on average, the structural similarity reaches 0.8%, and the fit is around 0.75. And its color difference can reach at least 11.2% with the increase of iterations. It indicates that the reduction algorithm of semantic segmentation and convolutional neural network greatly improves the accuracy of color reduction results and can obtain printmaking images with higher color quality.

The sub-barrier fusion hindrance has been observed in the domain of very low energies of astrophysical relevance. The measured fusion cross sections can be well estimated by using formula obtained by folding a Gaussian function for barrier height distribution with the expression for classical fusion cross section for fixed barrier. The parameters of the formula vary smoothly implying its usage in estimating the excitation function. In the present work, the effects of deformation and transfer on fusion reactions have been studied and the absence of neutron transfer channels has been correlated to the hindrance in heavy-ion fusion reactions. [ABSTRACT FROM AUTHOR]

The excitation functions of 69 Ga(α, n) 72 As, 69 Ga(α, 2n) 71 As, *Corresponding author:Email:rabirhanu@gmail.com, https://dx.doi.org/10.4314/eajbcs.v4i1.2S 69 Ga(α, 3n) Ga(α,x) 69 Ge, 69 Ga(α, x) 68 Ga and 69 Ga(α, x) 67 Ga reactions produced in the interaction of α-projectile with 69 Ga-target were studied at ≈ 10-50 MeV. The produced nuclei weredifferent isotopes of As, Ge, and Ga, some of which have important medical applications.The theoretical model predictionswere based on the statistical code COMPLETE, and thepredicted results were compared and discussed with existing experimental data. Goodagreement between the theoretical predictions and experimental results were obtained.Pearson's relational statistics showed moderate to strong positive correlations between thetheoretically predicted and experimentally measured reaction cross-sections. Furthermore,the present investigation revealed significant pre-compound contributions in the studiedenergy range. Therefore, it is important to consider the admixture of pre-equilibrium andequilibrium modes of reactions when predicting the reaction cross-sections.

Systematic measurements of nuclear reaction cross sections were done in the low energy range for the two reactions 45Sc(d,p)46Sc and 45Sc(α,n)48V. Thin foils of high-purity (99.95%) natural Sc targets (100% 45Sc), purchased from Good-Fellow, were irradiated with 10 and 20 MeV incident deuteron and α-particle energies, respectively, at beam current of 100 nA using MGC-20 cyclotron. For precise measurements, high-purity Ti and Cu foils were used for monitoring the actual deuteron and α-particle beam intensities, respectively. The conventional stacked-foil technique was applied for measurement and calculation of the cross section values using a high-resolution γ-ray spectrometer for measuring the radioactivity. Nuclear model code EMPIRE-3.2 was used for calculation of the investigated excitation functions. The obtained results were compared with the experimental values and TENDEL-2021 data which are based on TALYS-1.96 code calculations. The integrated yields for the two reactions, based on the proposed average excitation functions, were estimated. [ABSTRACT FROM AUTHOR]

• Activation cross sections of proton-induced reactions on manganese were measured up to 30 MeV. • The stacked-foil activation method and high-resolution gamma-ray spectrometry were used for the measurement. • Production cross sections of 51Cr and 54Mn were determined in this experiment. • The results were compared with the previous experimental data and the TENDL-2019 values. The excitation functions of the 55Mn(p,x)51Cr, 54Mn reactions were measured up to 30-MeV proton energy. The experiment was performed at the RIKEN AVF cyclotron using the stacked-foil activation technique. High-purity germanium (HPGe) detectors were used for the gamma-ray spectrometry. Obtained results were compared with previous experimental data and the prediction of the TALYS nuclear reaction model code available in the TENDL-2021 library. Physical thick target yields of 51Cr and 54Mn were derived from the measured cross sections. [ABSTRACT FROM AUTHOR]

• We conducted an experiment to measure activation cross sections of alpha-particle-induced reactions on natural tungsten. • The stacked-foil activation technique and high-resolution gamma-ray spectrometry were used for the measurement. • Production cross sections of 185,183m,183g,182gOs and 188g,186g,184g,183g,182g,181Re were determined up to 50 MeV. • The results were compared with the previous experimental data and the TENDL-2019 values. We measured activation cross sections of alpha-particle-induced reactions on natural tungsten targets. The stacked-foil activation technique and gamma-ray spectrometry were used. Production cross sections of 185,183m,183g,182gOs and 188g,186g,184g,183g,182g,181Re were determined. The results were compared with experimental literature data and the TENDL-2019 and TENDL-2021 values. The cross sections of the most reactions were determined for the first time. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) and machine learning (ML) methods have touched practically all aspects of our life. Their utility ranges from separating different quality agricultural produce to facial recognition to guiding us through most steps in our day-to-day life. In this perspective article, we demonstrate the utility of artificial neural network (ANN) method in fitting potential energy curves and surfaces and point out the potential applications to predicting and analyzing dynamical observables. Although the regression methods seem to be successful in fitting potential energy surfaces using limited ab initio data, the ANN method yields accurate fits of surfaces when enough number of ab initio points on the potential energy surface become available. The possibility of utilizing the ANN method for fitting excitation function data is pointed out and the implications are discussed. This perspective article illustrates how the artificial neural network can be used to interpolate accurately potential energy curves and surfaces for molecular systems and how the method can be extended to systems with avoided crossing of potential energy curves and to multidimensional excitation function data. [ABSTRACT FROM AUTHOR]

In view of several significant discrepancies in the excitation function of the 86Sr(p,n)86g+xmY reaction which is the method of choice for the production of the non-standard positron emitter 86Y for theranostic application, we carried out a careful measurement of the cross sections of this reaction from its threshold up to 16.2 MeV at Forschungszentrum Jülich (FZJ) and from 14.3 to 24.5 MeV at LBNL. Thin samples of 96.4% enriched 86SrCO3 were prepared by sedimentation and, after irradiation with protons in a stacked-form, the induced radioactivity was measured by high-resolution γ-ray spectrometry. The projectile flux was determined by using the monitor reactions natCu(p,xn)62,63,65Zn and natTi(p,x)48V, and the calculated proton energy for each sample was verified by considering the ratios of two reaction products of different thresholds. The experimental cross section data obtained agreed well with the results of a nuclear model calculation based on the code TALYS. From the cross section data, the integral yield of 86Y was calculated. Over the optimum production energy range Ep = 14 → 7 MeV the yield of 86Y amounts to 291 MBq/μA for 1 h irradiation time. This value is appreciably lower than the previous literature values calculated from measured and evaluated excitation functions. It is, however, more compatible with the experimental yields of 86Y obtained in clinical scale production runs. The levels of the isotopic impurities 87mY, 87gY, and 88Y were also estimated and found to be

Optical model potential and nuclear level density models have been used to study the production routes of radionuclides 68 G e and 82 S r because of their relatively long half-lives and use in 68 G e / 68 G a and 82 S r / 82 R b generators, which are used in PET imaging. The excitation function of the nuclear reactions 66 Z n (α , 2 n) 68 G e , 67 Z n (α , 3 n) 68 G e , 80 K r (α , 2 n) 82 S r , 82 K r (α , 4 n) 82 S r , 69 G a (p , 2 n) 68 G e , 71 G a (p , 4 n) 68 G e and 85 R b (p , 4 n) 82 S r for projectile energies ranging from threshold to 100 MeV have been determined using the nuclear reaction programming code TALYS1.96. α -induced reaction cross sections have been computed using Koning-Delaroche (KD) optical model potential (OMP) incorporating Watanabe's folding approach to α -nucleus potential and α -OMP of McFadden-Satchler. Moreover, the nuclear level densities from Hartree-Fock-Bogolyubov (HFB) Goriely's table and HFB Hilaire's combinatorial table have been suitably used to calculate level densities. The proton-induced reaction cross sections have been calculated using the KD OMP. Besides, nuclear level density from the phenomenological back-shifted Fermi gas model, generalized superfluid model, the microscopic nuclear level density of HFB Goriely's table, and HFB Hilaire's combinatorial table has been used for the calculation of level densities and the effect of these level density models on the calculated excitation function is studied. The examination of the consistent model with the measured nuclear reaction data available from Experimental Nuclear Reaction Data (EXFOR) is carried out by statistical analysis. Furthermore, the combination of nuclear model calculations compared with TALYS-based evaluated nuclear data library TENDL2021. The calculated excitation function for α -induced reactions determined using KD OMP incorporating α -potential of Watanabe and α -OMP of McFadden-Satchler produces agreement with EXFOR. [ABSTRACT FROM AUTHOR]

The hindrance in fusion of heavy-ion reactions crops up in the region of extreme sub-barrier energies. This phenomenon can be analyzed effectively using an uncomplicated straightforward elegant mathematical formula gleaned presuming diffused barrier with a Gaussian distribution. The mathematical formula for cross section of nuclear fusion reaction has been obtained by folding together a Gaussian function representing the fusion barrier height distribution and the expression for classical cross section of fusion assuming a fixed barrier. The variation of fusion cross section as a function of energy, thus obtained, describes well the existing data on sub-barrier heavy-ion fusion for lighter systems of astrophysical interest. Using this simple formula, an analysis has been presented from 16 O + 18 O to 12 C + 198 Pt, all of which were measured down to < 10 μ b. The agreement of the present theoretically calculated estimates with the measured values is excellent. The relatively smooth variation of the three parameters of this formula implies that it may be exploited to estimate the excitation function or to extrapolate cross sections for pairs of interacting nuclei which are yet to be measured. Possible extensions of the present methodology and its limitations have also been discussed. [ABSTRACT FROM AUTHOR]

The results of natW(p,xn)181;182m,g;183;184m,g;186Re reaction cross sections at the external proton beam of cyclotron C18/18 are presented. The excitation functions for the above mentioned radionuclides have been measured by the stacked-foil activation technique on high purity tungsten foils of natural isotopic composition. Due to the stacked-foil technique, measurements were performed for different proton energies from corresponding reaction thresholds up to 18 MeV. The spectrometric analyses of irradiated materials have been done by the High Purity Germanium (HPGe) detector. For all reactions, theoretical calculations of the excitation functions were calculated by TALYS 1.95 and EMPIRE 3.2 nuclear reaction codes. The obtained experimental results are compared with the theoretical models as well as with the available experimental data. [ABSTRACT FROM AUTHOR]

Activation cross sections of deuteron-induced reactions on natural gadolinium were measured up to 24 MeV. The stacked-foil activation technique and γ-ray spectrometry were used for the measurement. The production cross sections of 153,154m1,154m2,155,156,160,161Tb and 153,159Gd were determined. The cross sections were compared with previous experimental data and TENDL values. [ABSTRACT FROM AUTHOR]

Theoretical predictions were made using TALYS-1.95(G) and EMPIRE 3.2 reaction-model codes for 69Ge, 67Ge, and medically used 68Ge, 67Ga, 68Ga, 65Zn, 64Cu radionuclides produced in the interaction of α-projectile with 66Zn-target at 10–40 MeV α-energies. Pearson's statistical coefficients showed moderate to strong positive correlations between the theoretically predicted and experimentally measured production cross sections for radionuclides with practical medical applications. Furthermore, the present results indicated that a medium-sized cyclotron and a single α + 66Zn system (projectile + target system) might be an option for optimized production of 68Ge, 68Ga, 67Ga, 65Zn, and 64Cu radionuclides. [ABSTRACT FROM AUTHOR]

The excitation functions of 69Ga(α, n)72As, 69Ga(α, 2n)71As, 69Ga(α, 3n)70As, 69Ga(α, x)69Ge, 69Ga(α, x)68Ga and 69Ga(α, x)67Ga reactions produced in the interaction of α-projectile with 69Ga-target were studied at ≈ 10-50 MeV. The produced nuclei were different isotopes of As, Ge, and Ga, some of which have important medical applications. The theoretical model predictions were based on the statistical code COMPLETE, and the predicted results were compared and discussed with existing experimental data. Good agreement between the theoretical predictions and experimental results were obtained. Pearson's relational statistics showed moderate to strong positive correlations between the theoretically predicted and experimentally measured reaction cross-sections. Furthermore, the present investigation revealed significant pre-compound contributions in the studied energy range. Therefore, it is important to consider the admixture of pre-equilibrium and equilibrium modes of reactions when predicting the reaction cross-sections.

Cross sections of the 86Sr(p,3n)84mY, 86Sr(p,αn)82mRb, and 86Sr(p,x)85gSr reactions were measured from their respective thresholds up to 16.2 MeV and from 23.0 to 44.1 MeV at FZJ, and from 14.3 to 24.5 MeV at LBNL, using 96.4% enriched 86SrCO3 as target material. Thin targets prepared by sedimentation were irradiated with protons in a stacked-form, and the induced radioactivity was measured by high-resolution γ-ray spectrometry. Nuclear model calculations based on the code TALYS reproduced our experimental cross section data well. From the excitation functions, the integral yields of the above three radionuclides were calculated. The yield of 85gSr via the natSr(n,γ) process was also measured using the TRIGA Mark-II reactor at AERE, Savar. A comparison of the reactor and cyclotron production of carrier-added 85gSr is given. The production possibilities of the three investigated radionuclides in no-carrier-added forms at a 30 MeV cyclotron via new routes are discussed. [ABSTRACT FROM AUTHOR]

We perform a comprehensive analysis of complete fusion cross section data with the aim to derive, in a completely data-driven way, a model suitable to predict the integrated cross section of the fusion between light-to-medium mass nuclei at above barrier energies. To this end, we adopted a novel artificial intelligence approach, based on a hybridization of genetic programming and artificial neural networks, capable to derive an analytical model for the description of experimental data. The approach enables to perform a global search for computationally simple models over several variables and a considerable body of nuclear data. The derived phenomenological formula can serve to reproduce the trend of fusion cross section for a large variety of light to intermediate mass collision systems in an energy domain ranging approximately from the Coulomb barrier to the onset of multi-fragmentation phenomena. [ABSTRACT FROM AUTHOR]

Activation cross sections of alpha-particle-induced reactions on natural rhenium were measured. The stacked-foil activation technique and high-resolution gamma-ray spectrometry were used to derive the cross sections. The production cross sections of 190g, 189g, 188g, 187g, 186g, 185, 184Ir, 185Os, and 184g, 183gRe were determined up to 50 MeV. The cross sections of 185,184Ir were measured for the first time. The experimental results were compared with previous experimental data and theoretical calculations in the TENDL-2021 library. • The excitation functions of alpha-particle-induced reactions on natRe up to 50 MeV were measured. • The stacked-foil activation technique and gamma-ray spectrometry were used to derive the cross sections. • The production cross sections of 190g, 189g, 188g, 187g, 186g, 185, 184Ir, 185Os, and 184g, 183gRe were determined. • The results were compared with the previous experimental data and the TENDL data. [ABSTRACT FROM AUTHOR]

• Activation cross sections of 7Li-induced reactions on natCu were measured for possible monitor reactions. • The stacked-foil activation technique and high-resolution γ-ray spectrometry were used for the measurement. • Cross sections and thick target yields producing 69,68Ge, 67,66Ga and 69m,65Zn were determined. • Some reactions were found to be appropriate for the monitor reactions. Activation cross sections of 7Li-induced reactions on natCu were measured in order to investigate suitability of some reactions for monitoring experimental parameters. Cross sections producing 69,68Ge, 67,66Ga and 69m,65Zn were determined. Physical thick target yields were experimentally measured and compared with those calculated using the measured cross sections. The measured cross sections were verified by the agreements between the directly measured thick target yields and the thick target yields deduced from the measured cross sections. The 7Li-induced reactions on natCu for the production of 67,66Ga and 65Zn are suggested as monitor reactions. [ABSTRACT FROM AUTHOR]

BackgroundAccelerator-driven subcritical systems (ADS) are among the most promising options for next-generation nuclear power systems. Various radionuclides are produced during the process of protons bombarding the target in the ADS, and the cross-sections of various long-lived radionuclides have not been accurately measured. These long-lived nuclides are related to ADS radioactive waste treatment, therefore, accurate evaluation of long-lived radionuclides generated in ADS spallation targets is a key topic in applied research.PurposeThis study aims to determinate production cross-sections of natPb(p,x)207Bi and natPb(p,x)194Hg reactions according to measurement data, and compare them with existing experimental and theoretical results.MethodsThe proton activation method was employed to effectively estimate the cross section of long-lived nuclides produced by the interaction between protons and spallation target materials. Four proton-irradiated natural lead samples were irradiated with protons at energies of 40 MeV, 70 MeV, 100 MeV, and 400 MeV for 90 min, 75 min, 40 min, and 25 min, respectively. After cooling for approximately 20 a, the samples were measured using an ultralow background gamma spectrometer GeTHU in the China Jinping Underground Laboratory (CJPL), and the GeTHU detection efficiency was calculated using the Simulation and Analysis for Germanium Experiments (SAGE) simulation framework. Combined with the irradiation parameters of the samples, the total production cross-sections of the two nuclides were calculated using a cross-section calculation formula. Experimental results are evaluated and compared with those of existing studies.ResultsThe production cross-sections of natPb(p,x)207Bi reaction in the natural lead samples irradiated by protons with four different energies (40 MeV, 70 MeV, 100 MeV and 400 MeV) are calculated as (40.70±3.59) mb, (19.31±1.43) mb, (13.15±0.96) mb, and (2.90±0.22) mb, respectively. The calculated production cross-section of natPb(p,x)194Hg reaction in the natural lead sample irradiated by protons with an energy of 400 MeV is (57.07±7.83) mb. Based on the same samples, the measurement results of cross-section remain consistent within the error range. The cross-sections of natPb(p, x)207Bi are closer to TENDL's evaluated cross-sections. The cross-section of natPb(p, x)194Hg is consistent with the theoretical expectation of INCL++/ABLA. In addition, different sources that contribute to the total uncertainty of both reactions are explained in detail.ConclusionsThe production cross-sections of natPb(p,x)207Bi and natPb(p,x)194Hg reactions measured herein were calculated independently and showed good agreement with existing results. These results demonstrate that GeTHU is capable of measuring low-activity and long-lived radionuclides in the CJPL. Finally, the results of this study also provide the latest experimental evidence for the evaluation of radioactive waste in ADS.

• Activation cross sections of deuteron-induced reactions on natural chromium were measured up to 24 MeV. • The stacked-foil activation method and high-resolution gamma-ray spectrometry were used for the measurement. • Production cross sections of 48V, 51Cr, 52g,52m,54Mn were determined in this experiment. • The results were compared with the previous experimental data and the TENDL-2019 values. Radioisotopes in the transition elements such as 51Cr and 52gMn can be used for medical applications. Investigation on the production reactions of such radioisotopes is valuable. Therefore, excitation functions of the natCr(d,x)48V, 51Cr, 52g,52m,54Mn reactions were measured up to 24-MeV deuteron energy. The experiment was performed at the RIKEN AVF cyclotron. Stacked-foil activation method and gamma-ray spectrometry were used for the measurement. The results were compared with previous experimental data and the prediction values of TENDL-2019. Physical thick target yields of 51Cr and 52gMn were derived from the measured cross sections. [ABSTRACT FROM AUTHOR]

• The excitation functions of alpha-particle-induced reactions on natLa up to 50 MeV were measured. • The production cross sections of 139,138m,142Pr, and 141,139Ce were determined. • The results were compared with the previous experimental data and the TENDL data. • The physical yield of the medical radionuclide 142Pr was derived from the measured cross sections. We performed experiments to measure the activation cross sections of α-particle-induced reactions on natLa up to 50 MeV. The production cross sections of the medical radionuclide 142gPr and simultaneously formed 139,138mPr, and 141,139gCe were obtained. The stacked-foil activation method and the high-resolution γ-ray spectrometry were employed for the measurements. The results were compared with previous experimental data and theoretical values deduced by TALYS (TENDL library). The production cross section data for 139gCe and 138mPr were determined for the first time. [ABSTRACT FROM AUTHOR]

Activation cross-sections of the nuclear reactions natBa(p,x)135,132gLa, 135mBa and natCe(p,x)142,139,138mPr, 141,139,137mCe have been measured experimentally at the MGC-20 cyclotron, Cairo, Egypt, from their respective threshold energies up to about 14.7 MeV. Stacked foil irradiation technique and high-resolution gamma-ray spectroscopy were used. A comparison between the experimental and theoretical data derived from the nuclear model codes EMPIRE and TALYS (in the form of the TENDL library) was performed. The agreement in the low-energy region is fairly good. Integral yields of the produced radioisotopes were estimated from the present cross-section data and the results are discussed in terms of their production possibilities. [ABSTRACT FROM AUTHOR]

The excitation functions of 63Cu(p,n)63Zn, 65Cu(p,n)65Zn, 66Zn(p,n)66Ga, 67Zn(p,n)67Ga and 68Zn(p,n)68Ga reactions were computed using the TALYS-1.95 computer code from reaction threshold to 40 MeV energy to yield medically important radioisotopes. The influence of varying level density and effective imaginary potential on reaction cross-section has been investigated. Thus, investigated results have been discussed and compared with previously available experimental data. The analysis of the cross-sections at the maximum value of energy for different reactions exhibits that the (p,n) reaction is the most commonly occurring process. The results so obtained have been found in fair agreement with measured data within error bar limits. The compound and pre-compound nuclear reaction mechanisms have also been analyzed and found very significant for validation of the nuclear model with improved accuracy level. [ABSTRACT FROM AUTHOR]

A new proton-unbound isotope 204Ac was produced in the fusion-evaporation reaction Tm(40169Ca,5n)204Ac and identified via the recoil-α correlation at the gas-filled recoiled separators SHANS2 and SHANS. The excitation function for producing 204Ac was measured and the optimal beam energy was evaluated to be 212 MeV. Nineteen ER - α1 - α2 - α3 decay chains were observed for this isotope. Based on these chains, the α-particle energy and half-life of 204Ac were determined to be 7948(15) keV and 7.4−1.4+2.2 ms, respectively. Both are consistent with the theoretical prediction. The reduced α-decay width was deduced to be 49−15+10 keV, which indicates a favored α decay for 204Ac. In addition, more precise decay properties of Eα = 7883(15) keV and T1/2 = 7.7−1.6+2.7 ms were obtained for 205Ac.

SMB chromatography (simulated moving bed chromatography) is a separation science. The soft measurement modeling approach of SMB chromatographic separation process based on extreme learning machine (ELM) with variable excitation function was introduced as a method for determining component fineness and harvest of extract and residue. The soft-sensor model's supplemental variables, as well as the crucial economic and cultural forecasting indices, were chosen after reviewing the technique of SMB chromatographic separation. Second, five excitation functions (Sig, Sin, Hardlim, Tribas, and Radbas) are being used in the ELM neural network to generate the soft-sensor model, and the quantity of neurons in the hidden stratum of the ELM is determined.The simulation experiments consequences indicate that ELM neural network can availably achieve the accurate forecasting of key economic and technical indicators and fulfill the real-time, efficient and robust operation of SMB chromatographic separation process. [ABSTRACT FROM AUTHOR]

the Scandium-47 shows undertaking capability in therapeutic radionuclide, particularly in the single-photon emission computed tomography (SPECT) technique. In this study, for the production of the 47Sc, the proton interaction on natural titanium was investigated by the Karaj cyclotron. At first, the excitation functions for the production of 47Sc and accompanying impurities via proton bombardment of titanium targets were evaluated by three nuclear codes, TALYS-1.9, ALICE/ASH, and EMPIRE-3.2.2. The target thickness for the best range of suggested energy estimated through the stopping power using the SRIM-2013 code. The theoretical yields for each reaction were calculated using Simpson's integral. The natTi foil was irradiated by a 29.5 MeV incident proton beam in the Karaj Cyclotron. The total current irradiated on the target was 5 μA·h at the end of the bombardment. The liquid-liquid extraction (LLX) method was employed for the separation of radiochemical impurities. Quality control was performed by γ-ray spectrometry. The separation yield of scandium-47 was 95%. The results showed good agreement with simulated and published experimental data.

Activation cross sections of the α-particle-induced reactions on natCr were measured. A stacked foil activation technique and γ-ray spectrometry were used. Nickel-chromium alloy, nickel and titanium metallic foils were stacked as a target. The target was irradiated with a 51.2-MeV α-particle beam at the AVF cyclotron, RIKEN. The γ rays were measured for the irradiated foils using an HPGe detector. Production cross sections of 52gFe, 52g,54Mn, 48,51Cr and 48V radionuclides were determined. The cross sections determined in this experiment were compared with the literature data and found to be consistent with them. [ABSTRACT FROM AUTHOR]

Changes in the elements of the Earth system are closely related. Finding the key factors linked with hydrological changes is significant for in-depth analysis of hydrological changes. This study chooses polar motion, which is the movement of the Earth's rotational axis relative to its crust, as a key factor in the investigation of the physical processes of its interaction with several hydrological elements. First, the statistical relationships between polar motion and multi-hydrological elements (i.e., precipitation, evaporation, runoff, and terrestrial water storage) are investigated, using trend analysis, mutation analysis, cycle analysis, and correlation analysis methods, from basinal to global and from intra-annual to inter-annual scales. Second, their interactions are explored. The study quantifies the effect of hydrological changes on polar motion using the excitation function. It explores the effect of polar motion on hydrological changes based on the theory of equilibrium tides and atmospheric dynamics. The results show that they are significantly correlated and abruptly changed at a similar time. First, regional to global hydrological changes can significantly excite polar motion. From April 2002 to June 2020, the global terrestrial water storage decreased significantly (by approximately −4.68 mm yr−1), which significantly drove polar motion towards the direction of the Greenwich Meridian (by approximately 4.32 mas yr−1). Changes in regional terrestrial water storage also contributed significantly to directional changes in polar motion around 2005 and 2012. Second, polar motion can perturb the Earth's centrifugal force system and generate equilibrium tides, and thus further cause changes in sea-level pressure, wind, and water vapor transport. Results show that polar motion-induced water vapor flux divergences correlate significantly with actual precipitation and terrestrial water storage changes in the Yangtze River and the Pearl River basins. Their correlations are also significant when trends are removed, and the polar motion-induced changes are 4 to 14 months earlier. This study further demonstrates the relationship between polar motion and hydrological changes and helps to understand the related factors of hydrological changes in other Earth systems. [ABSTRACT FROM AUTHOR]

• Cross sections of alpha-particle-induced reactions on calcium were measured. • The stacked-foil activation technique and γ-ray spectrometry were used. • Production cross sections of 47,46,44m,44g,43Sc and 47Ca were derived up to 29 MeV. • The results were compared with the previous data and the TENDL-2019 values. Production cross sections of a medical radioisotope 47Sc via alpha-particle-induced reactions on natural calcium were measured up to 29 MeV. The stacked-foil activation technique and gamma-ray spectrometry were adopted for the experiment. Cross sections of simultaneously formed radionuclides 46,44m,44g,43Sc and 47Ca were also determined. Physical yields of the alpha-particle-induced reactions on natCa and 44Ca were deduced from the measured cross sections. [ABSTRACT FROM AUTHOR]

In order to solve the problem of low face recognition rate in controlled scene, an expression recognition algorithm based on residual rectification intensive convolutional neural network is proposed. This method takes convolutional neural network as the prototype. In the process of training model, the idea of residual network is introduced to correct the difference between the effect of test set and the effect of training set. The linear rectification operation of the residual block by the excitation function embedded in the convolution layer helps to express complex features. At the same time, the data intensive method is used to suppress the fast fitting of the deep neural network model during the training process, to improve its generalization performance on a given recognition task, and then to improve the robustness of the model learning effect. In the experiment, the method is applied to simulate the online teaching environment, and get effective facial expression recognition result in controlled scene. According to the experimental data, this method can effectively classify the facial image input under controlled conditions, and the highest accuracy is up to 91.7%. This research is helpful to the development of facial expression recognition and human-computer interaction. [ABSTRACT FROM AUTHOR]

Strip surface defects seriously impress the appearance of products, also lead to a decrease in wear resistance, corrosion resistance and the increase of fatigue strength of strip products, thus greatly reducing the service life of strip products. Therefore, a strip surface defect diagnosis algorithm by using on extreme learning machine (ELM) with variable excitation functions was proposed. Based on the neural network principle and the learning method of ELM, the seven excitation functions (Sigmoid, Sin, Hardlim, ReLu, Tanh, Morlet and Arctan) were used to establish the strip surface defect diagnosis model respectively. The neuron numbers of the hidden layer of ELM were analyzed experimentally. The simulation experiment results for the strip surface defect data set in UCI show that the ELM neural network can effectively diagnose the strip surface defect accurately. [ABSTRACT FROM AUTHOR]

The accelerator-driven subcritical system (ADS) is a competitive option for next-generation nuclear energy systems. Production cross sections of long-lived residual radioactive nuclides in a proton-nuclide reaction are basic quantities for the calculation of accumulated radioactivity in the use of ADS systems. This work presents the production cross sections of 102m Rh and 108m Ag in a natural lead ( nat Pb) target activated by 400 MeV protons. The nat Pb target was irradiated by a 400 MeV proton beam in NRC "Kurchatov Institute" and measured two decades later by a low background gamma spectrometer in China Jinping Underground Laboratory (CJPL). A spectrum analysis method based on simulated single-isotope spectrum and Bayesian peak fitting was employed to compute the activities and production cross sections of the residual nuclides. The experimentally measured cross-sections for 102m Rh and 108m Ag were 0.72 ± 0.05 mb and 0.76 ± 0.09 mb respectively. These values are approximately twice as high as those predicted by the QGSP&#95;INCLXX&#95;HP model and fall within the range predicted by the INCL4+ABLA and LAQGSM+GEM2 models for mass numbers A=102 and A=108. These findings offer new experimental insights for ADS research and provide a practical benchmark for theoretical models concerning proton-lead interactions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Excitation functions of the natFe (p, x) 52,54Mn, 55Co, 51Cr, 52Fe, and 46Sc reactions were measured at the proton energy of 87, 94 and 100 MeV, using the stacked foil activation technique followed by the off-line γ-ray spectrometry. The experiment was carried out on the separated sector cyclotron at the Institute of Modern Physics, Chinese Academy of Sciences. The natNi (p, x)57Ni and natAl (p, x)22Na reactions with known cross sections was used to monitor the proton beam intensity. The results from this work were compared with the existing literature data available in EXFOR data library and were found to be in good agreement. TALYS-1.95 is able to reproduce, in most cases, the experimental trend. Our experimental results were also compared with evaluated nuclear data from the ENDF/B-VIII.0, JENDL-4.0/HE, and PADF-2007 libraries as a function of proton energy, which reproduced the trend of the excitation functions of the experimental natFe (p, x) reaction cross-sections. These data expand our knowledge on the related excitation functions to confirm the existing trends and to give additional experimental values on a wider energy range. [ABSTRACT FROM AUTHOR]

Activation cross sections of proton-induced reactions on 141Pr were measured. Stacked foil activation technique and γ-ray spectrometry were adopted to derive the cross sections. The production cross sections of 141,140,139mNd, and 139Ce were determined up to 30 MeV. The physical yield of 140Nd was deduced using the measured cross sections of the 141Pr(p,2n)140Nd reaction. The physical yields of the proton- and deuteron-induced reactions on 141Pr and 3He-induced reaction on natCe for 140Nd production were compared. [ABSTRACT FROM AUTHOR]

Cross sections of alpha-particle induced reactions were determined on antimony targets using alpha-particle irradiation with a primary energy of 50 MeV. The standard stacked target technique, activation method and offline gamma-ray spectrometry were applied for determination of the reaction cross sections. Thin Sb targets prepared by vacuum evaporation onto Kapton backings were activated. Ti foils were inserted into the stack for monitoring the alpha-particle beam parameters and energy loss of the particles in the target by using the natTi(α,x)51Cr monitor reaction. Reaction cross sections for formation of 121,123,124,125,126I, 121m,g,123m,125mTe and 118m,120m,122gSb were determined and compared to the available literature data and theoretical estimation of the cross sections from the TENDL-2019 data library. [ABSTRACT FROM AUTHOR]

The activation cross sections of the alpha-particle-induced reactions on natural gadolinium up to 50 MeV were measured. The stacked foil technique, the activation method and the γ-ray spectrometry were used for the measurement. We determined the experimental production cross sections of 155,157,159Dy, 153,155,156g,160,161Tb and 153Gd. No previous experimental data of 155,159Dy, and 153Gd were found in the literature. The measured values were compared with the previous experimental data and the TENDL-2019 data. [ABSTRACT FROM AUTHOR]

• Activation cross sections of deuteron-induced reactions on praseodymium up to 24 MeV were measured. • The stacked-foil activation technique and the high-resolution γ-ray spectrometry were used. • Production cross sections of 141,140Nd, 142Pr, and 139Ce were determined. • The results were compared with the previous experimental data and the TENDL-2019 data. We measured activation cross sections of deuteron-induced reactions on 141Pr. The production cross sections of 141,140Nd, 142Pr, and 139Ce were determined up to 24 MeV using the stacked-foil activation technique and high-resolution γ-ray spectrometry. The derived cross sections were compared with experimental data studied earlier and theoretical model calculations. Our results are consistent with part of the previous data. [ABSTRACT FROM AUTHOR]

The (n,α) and (n,p) cross-sections and their isomeric ratios (σm/σg) were measured at 13–15 MeV for 92Mo and 95Mo by activation and off-line γ-ray spectrometry. The activated Mo samples combined with Al foils were used to obtain the cross-section values and the neutron flux, generated using the 3H(d,n)4He reaction. The cross-sections of the ground states were obtained using the metastable state absolute cross-sections and the residual nuclear decay rule. The excitation functions, total cross-sections, and isomeric ratios for the 92Mo(n,α)89m,gZr and 95Mo(n,p)95m,gNb reactions were calculated using the TALYS-1.95 software. 92Mo(n,α)89m + gZr and 95Mo(n,p)95m + gNb reaction excitation functions were obtained using the EMPIRE-3.2.3 package. These simulation results were compared with the corresponding experimental data and with the evaluated data from the ENDF/B-VIII.0, JEFF-3.3, CENDL-3, and ROSFOND libraries. Only partial agreements were observed. [ABSTRACT FROM AUTHOR]

For the first time, cross sections of the 151Eu(α, x n)155−x Tb (x = 2–6) reactions were measured by stack foil technique in the alpha particle range 60 → 19 MeV. Experimental excitation functions were compared with theoretical data from TENDL 2019 library and calculated by EMPIRE-3.2.3 code. Thick target yields for terbium radioisotopes were calculated. The possibility of the practical application of the studied reactions for the production of 152Tb and 149Tb was assessed. It was shown that higher energy of alpha particles is required to produce 149Tb. The production of 152Tb is affected by the influence of side reactions. It is possible to decrease the total content of impurities (153Tb+151Tb) at EOB to 18% of the activity of the 152Tb under 8-hour irradiation by limiting the energy range of incident particles to 42 → 34 MeV. The 152Tb yield will be 222 MBq/μA. [ABSTRACT FROM AUTHOR]