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GRO J1008-57, as a Be/X-ray transient pulsar, is considered to have the highest magnetic field in known neutron star X-ray binary systems. Observational data of the X-ray outbursts in GRO J1008-57 from 2017 to 2020 were collected by the Insight-HXMT satellite. In this work, the spin period of the neutron star in GRO J1008-57 was determined to be about 93.28 seconds in August 2017, 93.22 seconds in February 2018, 93.25 seconds in June 2019 and 93.14 seconds in June 2020. GRO J1008-57 evolved in the spin-up process with a mean rate of − ( 2.10 ± 0.05 ) × 10−4 s/d from 2009 – 2018, and turned into a spin down process with a rate of ( 6.7 ± 0.6 ) × 10−5 s/d from Feb 2018 to June 2019. During the type II outburst of 2020, GRO J1008-57 had the spin-up torque again. During the torque reversals, the pulse profiles and continuum X-ray spectra did not change significantly, and the cyclotron resonant scattering feature around 80 keV was only detected during the outbursts in 2017 and 2020. Based on the observed mean spin-up rate, we estimated the inner accretion disk radius in GRO J1008-57 (about 1 - 2 times of the Alfven radius) by comparing different accretion torque models of magnetic neutron stars. During the spin-down process, the magnetic torque should dominate over the matter accreting inflow torque, and we constrained the surface dipole magnetic field B ≥ 6 × 10 12 G for the neutron star in GRO J1008-57, which is consistent with the magnetic field strength obtained by cyclotron line centroid energy.

A new black hole X-ray binary (BHXRB) MAXI J1535-571 was discovered by MAXI during its outburst in 2017. Using observations taken by the first Chinese X-ray satellite, the Hard X-ray Modulation Telescope (dubbed as Insight-HXMT), we perform a joint spectral analysis (2-150 keV) in both energy and time domains. The energy spectra provide the essential input for probing the intrinsic Quasi-Periodic Oscillation (QPO) fractional rms spectra (FRS). Our results show that during the intermediate state, the energy spectra are in general consistent with those reported by Swift/XRT and NuSTAR. However, the QPO FRS become harder and the FRS residuals may suggest the presence of either an additional power-law component in the energy spectrum or a turn-over in the intrinsic QPO FRS at high energies.

We study the 2018 outburst of Aql X-1 via the monitor of all sky X-ray image (MAXI) data. We show that the outburst starting in February 2018 is a member of short-low class in the frame of outburst duration and the peak count rate although the outburst morphology is slightly different from the other fast-rise-exponential-decay (FRED) type outbursts with a milder rising stage. We study the partial accretion in the weak propeller stage of Aql X-1 via the MAXI data of the 2018 outburst. We report on the spectral analysis of 3 observations of Aquila X-1 obtained by Insight – hard X-ray modulation telescope (Insight-HXMT) during the late decay stage of the 2018 outburst. We discuss that the data taken by Insight-HXMT is just after the transition to the weak propeller stage. Our analysis shows the necessity of a comptonization component to take into account the existence of an electron cloud resulting photons partly up-scattered.

The objective of this study was to evaluate the effects of dietary linoleic acid (LA) on growth performance, antioxidant capacity, and lipid metabolism in pigeon squabs by supplementing LA in their parental diets. A completely randomized design that consisted of a control group, 1% dietary LA addition group (LA1%), 2% dietary LA addition group (LA2%), and 4% dietary LA addition group (LA4%) was used. Six squabs from each treatment were randomly sampled at the day of hatch and days 7, 14, and 21 after hatch. The results showed that parental dietary LA had no significant influence (P > 0.05) on body weight (BW) gain or relative organ weights (% of BW) in squabs. The activities of superoxide dismutase, catalase, and glutathione peroxidase in the LA1% were significantly increased (P

Background: Legume is well known for its high nutrition and health care values. Considering that starch is the main carbohydrate in legume, its properties directly affect the development and utilization of legume resources. Methods: Starches were extracted from the seeds and root tubers of five legumes. The morphological, structural and functional properties of the starches were investigated and compared using scanning electron microscopy, X-ray diffraction and attenuated total reflectance-Fourier transform infrared spectroscopy.Result: The granules of kudzu, broad bean and pigeon pea starches were kidney-shaped with a large size, while groundnut and white pea starches were small granules with a mixture of irregularly polyhedral and spherical shape. The five legume starches had different apparent amylose contents and exhibited remarkably different crystalline properties. Among the samples, the relative crystallinity of kudzu starch was the highest, while pigeon pea starch had the highest short-range ordered degree. The swelling power and water solubility of the five legume starches were also varied. Furthermore, white pea starch is more susceptible to acid and enzymatic hydrolysis than the four other starches. The results are important for the processing and utilization of legume starches and can provide reference for the development of legume-based functional food.

Pulmonary atresia with a ventricular septal defect and major aortopulmonary collateral arteries is an extremely rare congenital disorder characterized by a high risk of maternal mortality. We present the case of a 24-year-old primigravid woman with uncorrected pulmonary atresia, ventricular septal defect and major aortopulmonary collateral arteries who presented at 35+5 weeks’ gestation. Based on the pathophysiology of the congenital cardiac lesion, cesarean delivery was performed under epidural anesthesia under management by a multidisciplinary team. This report highlights the anesthesia management of a rare uncorrected congenital cardiac lesion for cesarean delivery.

Using isochronous mass spectrometry at the experimental storage ring CSRe in Lanzhou, the masses of $^{82}$Zr and $^{84}$Nb were measured for the first time with an uncertainty of $\sim 10$ keV, and the masses of $^{79}$Y, $^{81}$Zr, and $^{83}$Nb were re-determined with a higher precision. %The latter differ significantly from their literature values. The latter are significantly less bound than their literature values. Our new and accurate masses remove the irregularities of the mass surface in this region of the nuclear chart. Our results do not support the predicted island of pronounced low $\alpha$ separation energies for neutron-deficient Mo and Tc isotopes, making the formation of Zr-Nb cycle in the $rp$-process unlikely. The new proton separation energy of $^{83}$Nb was determined to be 490(400)~keV smaller than that in the Atomic Mass Evaluation 2012. This partly removes the overproduction of the $p$-nucleus $^{84}$Sr relative to the neutron-deficient molybdenum isotopes in the previous $\nu p$-process simulations.

International audience; The decay of the lightest nucleus with Tz=−3 , 22 Si, was studied by a silicon array. A charged-particle group at 5600 (70) keV in the decay-energy spectrum was identified experimentally as β -delayed two-proton emission from the isobaric analog state (IAS) of 22 Al. Experimental results of the IAS fed by a superallowed Fermi transition were compared with our large-scale shell-model calculations. The ground-state mass of 22 Si was obtained indirectly in the experiment for the first time. Two-proton separation energy for 22 Si is deduced to be −108 (125) keV, which indicates that it is a very marginal candidate for two-proton ground-state emission.

Short-lived 46 Cr, 50 Fe and 54 Ni were studied by isochronous mass spectrometry at the HIRFL-CSR facility in Lanzhou. The measured precision mass excesses ( M E ) of 46 Cr, 50 Fe and 54 Ni are − 29471 ( 11 ) keV , − 34477 ( 6 ) keV and − 39278 ( 4 ) keV , respectively. The superallowed 0 + → 0 + β -decay Q values were derived to be Q EC ( Cr 46 ) = 7604 ( 11 ) keV , Q EC ( Fe 50 ) = 8150 ( 6 ) keV and Q EC ( Ni 54 ) = 8731 ( 4 ) keV . The values for 50 Fe and 54 Ni are by one order of magnitude more precise than the adopted literature values. By combining the existing half-lives and branching ratios, we obtained the corrected F t values to be F t ( Fe 50 ) = 3103 ( 70 ) s and F t ( Ni 54 ) = 3076 ( 50 ) s . The main contribution to the F t uncertainties is now due to β -decay branching ratios, still, more high-precision measurements of the half-lives, the masses, and especially the branching ratios are needed in order to satisfy the requirements for a stringent CVC test.

Journal of physics / Conference Series 875, 012008 (2017). doi:10.1088/1742-6596/875/2/012008, Published by IOP Publ., Bristol

Accuracy of nuclear mass measurements in storage rings depends critically on the accuracy with which the revolution times of stored ions can be obtained. In such experiments, micro-channel plates (MCP) are used as timing detectors. Due to large phase space of injected secondary beams, a large number of ions cannot be stored in the ring and is lost within the first few revolutions. However, these ions interact with the detector and can saturate the MCP and thus deteriorate its performance. In order to eliminate such effects, a fast, pulsed high-voltage power supply (PHVPS) has been employed which keeps the detector switched-off during the first few revolutions. The new detector setup was taken into operation at the Experimental Cooler-Storage-Ring CSRe in Lanzhou and resulted in a significant improvement of the detector amplitude and efficiency characteristics.

In isochronous mass spectrometry (IMS) established in heavy-ion storage rings the revolution times of the stored secondary ions should be independent of their velocity spread. However, this isochronous condition is fulfilled only in first order and in a small range of revolution times. To correct for the non-isochronicity an additional measure of the velocity or magnetic rigidity of each stored ion is required. For this purpose two new time-of-flight (TOF) detectors were installed in a straight section of the experimental Cooler Storage Ring CSRe in Lanzhou. The performance of the new time-of-flight (TOF) detectors, which is crucial for the achievable efficiencies and mass resolving power, was significantly improved. The time resolution of the TOF detector in offline tests was σ = 18.5 ± 2 ps . The detector setup was put into operation with a stable beam of 78Kr.

To improve heat transfer performance and reduce erosion of economizers in coal-fired power plants, firstly the heat transfer and erosion characteristics is numerically studied for the single H-type finned oval tube with enhanced heat transfer structures including bleeding dimples, longitudinal vortex generators (LVGs), and compound dimple-LVG. The simulation results show that the oval tube with compound LVG-dimple achieves the highest overall heat transfer performance while the oval tube with LVG works most efficiently in the anti-wear performance. Then based on the H-type finned oval tube, the LVG structure on the first row of tubes together with hemisphere protrusions design, while the compound LVG-dimple on the rest tubes are also simulated. The optimized H-type finned oval tube bank heat exchanger is demonstrated of high performance on both heat transfer and anti-wear.

The periodic time modulations, found recently in the two-body orbital electron capture (EC) decay of both, hydrogen-like 140Pr58+ and 142Pm60+ ions, with periods near to 7 s and amplitudes of about 20%, were re-investigated for the case of 142Pm60+ by using a 245 MHz resonator cavity with a much improved sensitivity and time resolution. We observed that the exponential EC decay is modulated with a period T = 7.11 ( 11 ) s , in accordance with a modulation period T = 7.12 ( 11 ) s as obtained from simultaneous observations with a capacitive pick-up, employed also in the previous experiments. The modulation amplitudes amount to a R = 0.107 ( 24 ) and a P = 0.134 ( 27 ) for the 245 MHz resonator and the capacitive pick-up, respectively. These new results corroborate for both detectors exactly our previous findings of modulation periods near to 7 s , though with distinctly smaller amplitudes. Also the three-body β + decays have been analyzed. For a supposed modulation period near to 7 s we found an amplitude a = 0.027 ( 27 ) , compatible with a = 0 and in agreement with the preliminary result a = 0.030 ( 30 ) of our previous experiment. These observations could point at weak interaction as origin of the observed 7 s -modulation of the EC decay. Furthermore, the data suggest that interference terms occur in the two-body EC decay, although the neutrinos are not directly observed.

The low-energy astrophysical S factors of the Li 6 ( p , γ ) Be 7 reaction have been investigated on a 320 kV platform at the Institute of Modern Physics in Lanzhou. The experimental S factor of this reaction shows an interesting sizable drop contrary to any existing theoretical expectations at energies below 200 keV. Such drop has not been fully understood yet and may reflect a novel reaction mechanism. The appearance of an interesting new positive-parity 1 / 2 + or 3 / 2 + resonance at E c . m . ≈ 195 keV is discussed. This study shows the danger of extrapolating experimental data over too large an energy range and demonstrates the need for careful direct experimental studies of reaction cross sections at or near stellar energies. In addition, our new results are discussed in the framework of a SUSY assisted Big-Bang Nucleosynthesis ( BBN ) model.

'Zill;' mango was bagged with four types of bags: adhesive-bonded fabric bag, yellow/black double layer bag, single white layer bag and single yellow bag. The results showed that bagging with single white bag significantly reduced contents of chlorophylls and carotenoids and significantly increased contents of anthocyanins and flavonoids in peel than those of other treatments, and also showed higher peel lightness, chroma and hue angle than those of other treatments. All these changes after single white bagging resulted in purple-red in maturity green periods and pink in ripe periods. Fruit bagged with single white bag had highest contents of vitamin C, titratable acids, soluble solids, sucrose, glucose and fructose, while those bagged with yellow/black double layer bags had significantly lower contents of chlorophylls, carotenoids, anthocyanins, and flavonoids than those of other treatments. Though peel lightness and chroma were remarkable higher, hue angle was significantly lower than those of other treatments. Therefore, yellow/black double layer bags tended to produce fruits with light yellow peel color in maturity green periods and orange-yellow peel in ripe periods and also worse internal quality fruits. The results showed that single white bag could be a promising practice for mango production.

Background: Fragment yields exhibit a strong odd-even staggering (OES). This OES has been experimentally observed in different fragmentation reactions with different projectile-target combinations. However, the experimental data are still scarce for fragments close to drip lines and the origin of this OES is not well understood.Purpose: More experimental data are needed to explore the origin of this OES in fragment yields and to validate fragmentation reaction models, especially for nuclei close to the drip lines. To study the pronounced OES near the proton drip line, we measured the yields of ${T}_{z}=\ensuremath{-}1$ and ${T}_{z}=\ensuremath{-}3/2$ nuclei over a wide range of mass number.Methods: The combination of a fragment separator and a storage ring at the Heavy Ion Research Facility in Lanzhou has been used to measure the yields of ${T}_{z}=\ensuremath{-}1$ and ${T}_{z}=\ensuremath{-}3/2$ fragments, produced by $^{58}\mathrm{Ni}$ projectiles impinging on a beryllium target at an energy of about 463 MeV/nucleon.Results: A very strong OES is observed in the measured yields of both ${T}_{z}=\ensuremath{-}1$ and ${T}_{z}=\ensuremath{-}3/2$ fragments. Our experimental data demonstrate that the shell structure has a significant impact on the magnitude of this OES. A comparison of different fragmentation reaction data indicates that this OES is almost independent of the projectile-target combinations and the fragmentation energy between 140 and 650 MeV/nucleon.Conclusions: Our study reveals that the OES of fragment yields originates mainly from the OES of particle-emission threshold energies, which is very close to the OES of fragment yields when the Coulomb barrier is considered in particle-emission threshold energies.

HIAF (High Intensity heavy ion Accelerator Facility), a new facility planned in China for heavy ion related researches, consists of two ion sources, a high intensity Heavy Ion Superconducting Linac (HISCL), a 45 Tm Accumulation and Booster Ring (ABR-45) and a multifunction storage ring system. The key features of HIAF are unprecedented high pulse beam intensity and versatile operation mode. The HIAF project aims to expand nuclear and related researches into presently unreachable region and give scientists possibilities to conduct cutting-edge researches in these fields. The general description of the facility is given in this article with a focus on the accelerator design.

We have measured the rate of negative ion formation in F+-C60 collisions at different projectile velocities (v • 0.1 a.u to 0.4 a.u.). The measured rate has been found to decrease from 9.6% to 7.1% for projectile energy increasing from 7.3 keV to 18.3 keV. The fragmentation patterns of C60r+multicharged ions charged r+ formed in the collisions have been analyzed.

Relative yields of fragments following the 78Kr projectile fragmentation in a beryllium target were measured in a storage ring by using isochronous mass spectrometry (IMS). Odd–even staggering of the relative fragment yields is observed and can be explained by the odd–even staggering of the particle-emission threshold energies. IMS is a complementary technique to γ-ray spectroscopy for measuring isomeric ratios, in particular for nuclides with long lifetimes. It was found that the isomeric yield ratios in 53Fe are almost constant for different longitudinal momenta.

Strong odd-even staggering (OES) of the yields of fragments, produced by fragmenting Kr78 projectiles, has been measured by employing the combination of an in-flight fragment separator and a storage ring. It is shown that the OES of fragment yields of Tz=−1/2 and Tz=1/2 mirror nuclei critically depends on both pairing and shell structure, especially at the closed shells Z=20 and 28. A comparison of the relative OES of yields and of particle-emission threshold energies reveals unambiguously that the origin of the OES of fragment yields is mainly determined by the OES of the particle-emission threshold energies, which contain both pairing and shell effects.

International audience; The statistical dissociation of C702+ has been studied as a function of the internal energy using collision induced dissociation under energy control (CIDEC). Doubly charged ions C702+ were prepared in F+ (3 keV) + C70 → F− + C702+ collisions. Up to seven successive evaporation of C2 have been observed in a time range of 1.7 μs. The dissociation energies of C70-2m2+ (m=1-7) were determined using a statistical cascade model to reproduce the excitation energy distribution of C702+ parent ions for each dissociation channel. Results are in good agreement with previous theoretical calculations.

Physics letters / B 735, 327 - 331 (2014). doi:10.1016/j.physletb.2014.06.046, Published by North-Holland Publ., Amsterdam

In the last two decades a number of nuclear structure and astrophysics experiments were performed at heavy-ion storage rings employing unique experimental conditions offered by such machines. Furthermore, building on the experience gained at the two facilities presently in operation, several new storage ring projects were launched worldwide. This contribution is intended to provide a brief review of the fast growing field of nuclear structure and astrophysics research at storage rings., XVIth International Conference on Electro-Magnetic Isotope Separators and Techniques Related to their Applications, December 2--7, 2012 at Matsue, Japan

The accretion of hydrogen-rich material onto carbon-oxygen white dwarfs (CO WDs) is crucial for understanding type Ia supernova (SN Ia) from the single-degenerate model, but this process has not been well understood due to the numerical difficulties in treating H and He flashes during the accretion. For the CO WD masses from 0.5 to $1.378\,{M}_\odot$ and accretion rates in the range from $10^{-8}$ to $10^{-5}\,{M}_\odot\,\mbox{yr}^{-1}$, we simulated the accretion of solar-composition material onto CO WDs using the state-of-the-art stellar evolution code of {\sc MESA}. For comparison with the steady-state models (e.g \citet{nskh07}), we firstly ignored the contribution from nuclear burning to the luminosity when determining the Eddington accretion rate and found that the properties of H burning in our accreting CO WD models are similar to those from the steady-state models, except that the critical accretion rates at which the WDs turn into red giants or H-shell flashes occur on their surfaces are slightly higher than those from the steady-state models. However, the super-Eddington wind is triggered at much lower accretion rates, than previously thought, when the contribution of nuclear burning to the total luminosity is included. This super-Eddington wind naturally prevents the CO WDs with high accretion rates from becoming red giants, thus presenting an alternative to the optically thick wind proposed by \cite{hkn96}. Furthermore, the super-Eddington wind works in low-metallicity environments, which may explain SNe Ia observed at high redshifts., 14 pages, 4 figures, 1 table. Accepted for publication in ApJL

The cross section ratios of the double, triple and quadruplicate ionization to the single ionization of argon were measured by 1.5–7.5 MeV partially stripped oxygen ion (q = 1–4) bombardment. The Auger and the charge exchange processes are discussed and subtracted from the total multiple ionization ratios in order to study the mechanism of the direct multiple ionization of argon by partially stripped ions in the present energy range. It is found that the obtained ratios of the multiple ionization cross sections to those of the direct single ionization of argon agree well with the (νqeff)−2n+2 law for 1.5–7.5 MeV Oq+ (q = 1–4) impinging ions.

The double to single ionization cross section ratios of helium by partially stripped carbon ions have been measured for projectile charge states ranging from +1 to +4 and impact energies from 1.5 to 7.5 MeV. The effective charge effect in partially stripped ion-helium collision is presented. It is found that the effective charge qeff increases as the impinging energy increases and qeff shows a modest dependence upon the projectile charge state in the present energy range. The projectile charge state, projectile and target electronic state dependences of the effective charge effect is discussed using orbital interpenetrating. The nCTMC calculations were carried out to investigate the energy dependence of the effective charge. By introducing effective charge the cross section ratio of helium obtained in the present work is in good agreement with the ( V q eff ) −2 law.

The double and single ionization cross section ratios of helium by partially stripped carbon, oxygen and fluorine ions are measured for projectile charge states ranging from +1 to +4 and impact energies from 1.5 MeV to 7.5 MeV. The effective charge effect in partially stripped ion-helium collisions is studied. It is found that the effective charge qeff increases as the impinging energy increases and qeff shows a modest dependence upon the projectile charge state in the present energy range. The projectile charge state, projectile energy, projectile and target electronic state dependences of the effective charge effect may be explained using orbital interpenetrating.

Increasing interest has been seen in applying fuzzy set theory to power systems problems from the number of publications on this topic. As a relatively new research topic a need is felt to pay more attention to the understanding of the basic principles of the theory and the identification of problems suitable for solving by this method. This paper presents a survey of publications on applications of fuzzy set theory to power systems and the basic procedures for fuzzy set based methods to solve specific power systems problems. Simple numerical examples are used to show the practical procedures of problem formulation and solution. Theses examples are: generator maintenance scheduling, dynamic programming, and power system stabiliser. >

Knowledge of atomic masses is indispensable in nuclear structure and nuclear astrophysics. In the last two decades, majority of experimental data on nuclear masses stems from measurements of stored ions. The ions can be stored at low energies in a Penning trap or at significantly higher energies in a storage ring. In both cases revolution frequencies of ions trapped in a confining magnetic field are determined which enables high-precision mass measurements. In this contribution we sketch the experimental techniques and recent results. Future perspectives at the new generation radioactive beam facilities are outlined. © Copyright owned by the author(s).

The L X-rays of 71 Lu, 73 Ta and 79 Au were produced by 1.5–4.5 MeV alpha particle bombardment. The emitted L α , L γ1 and L γ2,3 lines were selected to convert X-ray production cross sections into ionisation cross sections. The ionisation cross sections obtained were compared with the predictions of the ECPSSR theory. A reasonable agreement of L 3 -subshell ionisation cross sections between the present experiment and the ECPSSR theory is found. The departures of the measured L 2 -subshell ionisation cross sections from the ECPSSR theory are discussed.

The M x-rays of Th and U have been produced by alpha particle bombardment in the energy range of 2.5-4.5 MeV. N6,7 → M5(Mα), N6 → M4(Mβ), N5 → M3(Mγ), N4 → M2 and N2 → M1 lines were selected to deduce M-subshell x-ray production cross sections. The radiative transition rates and the Coster-Kronig yields and M-subshell fluorescence yields were used to convert the x-ray production cross sections into M-subshell ionization cross sections. The deduced M-subshell ionization cross sections were compared with the ECPSSR predictions. The discrepancies of our experimental results from the theoretical calculations are discussed.

Masses of neutron-deficient Ni-58 projectile fragments have been measured at the HIRFL-CSR facility in Lanzhou, China employing the isochronous mass spectrometry technique. Masses of a series of short-lived T-z = -3/2 nuclides including the Cr-45 nucleus have been measured with a relative uncertainty of about 10(-6)-10(-7). The new Cr-45 mass turned out to be essential for modeling the astrophysical rp-process. In particular, we find that the formation of the predicted Ca-Sc cycle in X-ray bursts can be excluded.

We have measured the differential cross-sections in F3+–C60 collisions at low velocity (v=0.18 a.u.). Using coincidence measurements between the ejected electron number and recoil ions, we have estimated the initial charge state of C60 parent ions associated with neutral outgoing projectiles to range from 4+ to 7+. We found that the formation of anions is correlated with the strong excitation of C60 (average excitation energy about 160 eV). The cross-section of the production of the anion has been found to be 25 a.u. This value is in agreement with the scenario of anion formation in two steps. In the first step, F3+ ions are neutralized by multicollision on the C60 surface. In the second step and at the exit part of the collision, the electron attachment process occurs. For the production of a stable anion, the capture of electrons on carbon must occur directly to the ground states of F−, giving many electron vacancies on C60. This process explains the observation of strong electronic and vibronic excitations of C60 leading to electron emission and multifragmentation processes.