Near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) have enormous potential for all kinds of applications, both non-destructive testing and biological applications. The development of broadband NIR phosphors with good thermal stability for a wide range of applications remains a challenge. This work successfully synthesized a layered structure ultra-broadband NIR phosphor Sr3Ga2Ge4O14:Cr3+ (SGGO:Cr3+) under 431 nm excitation and achieved a spectrum adjusted from 750 nm to 900 nm in a two-stage ultra-broadband emission with a full width at half maximum (FWHM) varying between 257 and 336 nm by controlling the Cr3+ concentration. In particular, SGGO:0.15Cr(3+) has a FWHM of 257 nm and the internal quantum efficiency (IQE) of 36.67%, while the emission intensity at 423 K remained at 76% of room temperature. Finally, SGGO:0.03Cr(3+) and SGGO:0.15Cr(3+) phosphors were used with 430 nm blue light chips to produce NIR pc-LEDs devices and applied to night vision and human palm penetration, as well as plant illumination, revealing the potential of SGGO:Cr3+ for multiple ap-plications. The potential of SGGO:Cr3+ for a variety of applications was demonstrated.(c) 2022 Elsevier Ltd. All rights reserved.

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

Currently, near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) have become a research hotspot, however, the NIR phosphors continue to face the problems of narrowband emission and poor thermal stability. Therefore, in order to solve these problems, La3SnGa5O14:xCr3+ phosphors with ultra-broadband NIR emission were obtained by multiple lattice sites occupation, featuring ultra-broadband emission in the range of 650–1300 nm with full width at half-maximum (FWHM) up to 333 nm under 437 nm excitation. By tuning the concentration of Cr3+, the FWHM value can reach 333–417 nm La3SnGa5O14:Cr3+ also exhibits favorable thermal stability, maintaining 90.5% and 67% of the initial intensity at 373 K and 423 K, respectively. The NIR pc-LEDs were manufactured by combining the blue light chip with La3SnGa5O14:Cr3+ phosphor. When the NIR pc-LED was switched off, no image could be generated from the infrared camera. Instead, the image captured by the infrared camera was visible in the light of the NIR pc-LED lamp. Such results imply that La3SnGa5O14:Cr3+ may be a prospective candidate for future biological accurate nondestructive detection and night-vision technology.

Excited states in Ba-131 and Ce-133 were studied using in-beam gamma-ray spectroscopy through the Sn-122(C-13, 4n) Ba-133 and Te-125(C-12, 4n) Ce-133 reactions, respectively. A strongly coupled band, associated with the nu g(7/2) [404]7/2(+) configuration, was identified in Ba-131 and Ce-133. It is the first time to observe the nu g(7/2) [404]7/2(+) bands in the N = 75 isotones. The signature partners exhibit considerable energy splitting in comparison with those in the pi g(7/2) [404]7/2(+) bands in the odd-A Ta and Re isotopes. Extensive cranked shell model and quasiparticle-plus-triaxial-rotor model calculations reveal the origin of the signature splitting, which depends not only on the triaxiality, but also on the configuration mixing with nearby low- j orbitals.

The beta-delayed two-proton (beta 2p) decay of S-27 was studied using a state-of-the-art silicon array and Clover-type HPGe detectors. An energy peak at 6372(15) keV with a branching ratio of 2.4(5)% in the decay-energy spectrum was identified as a two-proton transition via the isobaric-analog state in P-27 to the ground state of Al-25 in the beta decay of S-27. Two-proton angular correlations were measured by the silicon array to study the mechanism of two-proton emission. Based on experimental results and Monte Carlo simulations, it was found that the main mechanism for the emission of beta 2p by S-27 is of sequential nature.

A detailed beta-decay spectroscopic study of Al-22 was performed at the Radioactive Ion Beam Line in Lanzhou. With the beta-gamma-particle coincidence measurement by a high-resolution DSSD particle detection array and a high efficiency gamma-ray detection array, total eight excited states in Mg-22 fed by Gamow-Teller transitions was newly identified. The one-proton, two-proton, and a decays of the IAS at 14046(5) keV in Mg-22, which were partly observed in different experiments before, were identified simultaneously in the present work, providing accurate spectroscopic information about its decay. A more complete beta-decay scheme of Al-22 was constructed and compared to the shell-model calculations with the USD-type Hamiltonians, USDC and USDB.

The beta decay of P-26 was used to populate the astrophysically important E-x = 5929.4(8) keV, J(pi) = 3(+) state of Si-26. Both beta-delayed protons at 418(8) keV and gamma rays at 1742(2) keV emitted from this state were measured simultaneously for the first time, and the corresponding absolute intensities have been estimated as 11.1(12)% and 0.59(44)%, respectively. The half-life of P-26 has been determined to be 43.6(3) ms, which is in good agreement with previous experimental results. Besides, shell-model calculations with weakly bound effects were performed to investigate the decay properties of other resonant states and a spin-parity of 4(+) rather than 0(+) is favored for the E-x = 5945.9(40) keV state. Combining the experimental results and theoretical calculations, the Al-25(p, gamma) Si-26 reaction rate in explosive hydrogen burning environments was calculated. The new determined total reaction rate is consistent with previous studies at T > 0.2 GK.

The mass of P-27 is expected to impact the X-ray burst (XRB) model predictions of burst light curves and the composition of the burst ashes, but large uncertainties and inconsistencies still exist in the reported P-27 masses. We have used the beta-decay spectroscopy of S-27 to determine the most precise mass excess of P-27 to date to be -659(9) keV, which is 63 keV (2.3 sigma) higher and a factor of 3 more precise than the value recommended in the 2016 Atomic Mass Evaluation. Based on the new P-27 mass, the Si-26(p, gamma)P-27 reaction rate and its uncertainty were recalculated using Monte Carlo techniques. We also estimated the previously unknown mass excess of S-27 to be 17678(77) keV, based on the measured beta-delayed two-proton energy and the Coulomb displacement energy relations. The impact of these well-constrained masses and reaction rates on the modeling of the explosive astrophysical scenarios has been investigated by post-processing XRB and hydrodynamic nova models. Compared to the model calculations based on the masses and rates from databases, the abundance of A = 26 in the burst ashes is increased by a factor of 2.4, while no substantial change was found in the XRB energy generation rate or the light curve. Our calculation also suggests that S-27 is not a significant waiting point in the rapid proton capture process, and the change of the Si-26(p, gamma)P-27 reaction rate is not sufficiently large to affect the conclusion previously drawn on the nova contribution to the synthesis of galactic Al-26. (C) 2020 The Author. Published by Elsevier B.V.

Complete fusion (CF) cross section measurement for the weakly bound Be- 9 projectile interacting with the intermediate mass target Y-89 has been extended to energies greater than the fusion barrier, by implementing off-line characteristic gamma-ray detection techniques. The available experimental data for the Be-9 + Y-89 reaction system were compared with the theoretical predictions, using the PLATYPUS code that is based on a classical dynamical model. By introducing the breakup probability that deduced in the literature from the fitting of the experimental data, the model managed to reproduce the CF cross sections of Be-9 beam with targets of different atomic mass. Through the study, it is revealed that the extended CF excitation function for the Be-9 + Y-89 system is consistent with the systematical behavior that the prompt-breakup probability at above-barrier energies is roughly independent of the target in the reactions induced by the same weakly bound projectiles.

Complete fusion (CF) cross section measurement for the weakly bound 9Be projectile interacting with the intermediate mass target 89Y has been extended to energies greater than the fusion barrier, by implementing off-line characteristic γ -ray detection techniques. The available experimental data for the 9Be + 89Y reaction system were compared with the theoretical predictions, using the PLATYPUS code that is based on a classical dynamical model. By introducing the breakup probability that deduced in the literature from the fitting of the experimental data, the model managed to reproduce the CF cross sections of 9Be beam with targets of different atomic mass. Through the study, it is revealed that the extended CF excitation function for the 9Be + 89Y system is consistent with the systematical behavior that the prompt-breakup probability at above-barrier energies is roughly independent of the target in the reactions induced by the same weakly bound projectiles.

β decay of ^26P was used to populate the astrophysically important E_x=5929.4(8) keV J^π=3^+ state of ^26Si. Both β-delayed proton at 418(8) keV and gamma ray at 1742(2) keV emitted from this state were measured simultaneously for the first time with corresponding absolute intensities of 11.1(12)% and 0.59(44)%, respectively. Besides, shell model calculations with weakly bound effects were performed to investigate the decay properties of other resonant states and a spin-parity of 4^+ rather than 0^+ was favored for the E_x=5945.9(40) keV state. Combining the experimental results and theoretical calculations, ^25Al(p,γ)^26Si reaction rate in explosive hydrogen burning environments was calculated and compared with previous studies.

Background: beta-decay spectroscopy provides valuable nuclear physics input for accurate modeling of nova and x-ray burst observables and a stringent test for shell-model theories far from the stability line. The decay scheme of S-27 is complicated and far from being understood due to a lack of experimental data prior to this work. Purpose: We aim to experimentally constrain the thermonuclear Si-26(p, gamma)P-27 reaction rate and to probe the possible mirror asymmetry in S-27 and Na-27 decays. Method: The S-27 ions were collected by double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors, so the positrons, protons, and gamma rays emitted in the decay were measured simultaneously. Results: The precise resonance energy and the ratio between gamma and proton partial widths of the key 3/2(+) resonance were obtained, thereby determining the Si-26(p, gamma)P-27 reaction rate based mainly on experimental constraints. The half-life of S-27, the excitation energies, beta-feeding intensities, log ft values, and Gamow-Teller transition strengths for the states of P-27 populated in the beta decay of S-27 were determined. A more complete S-27 P-decay scheme was constructed and compared to the beta decay of mirror nucleus Na-27 and to the shell-model calculations with the universal sd (USD) Hamiltonian taking into account the shift of single-particle energies and the reduction of two-body matrix elements. Conclusions: This work yields a new Si-26(p, gamma)P-27 reaction rate two orders of magnitude lower than the rate recommended in the reaction rate libraries at around 0.1 GK. Experimental evidence for the observation of mirror asymmetries for the Gamow-Teller transitions of S-27 and Na-27 is also provided. The shell-model calculations using a modified USD interaction related to the weakly bound proton 1s(1/2) orbit give a reasonable description of the decay properties of S-27.

Background: Beta-decay spectroscopy provides valuable nuclear physics input for thermonuclear reaction rates of astrophysical interest and stringent test for shell-model theories far from the stability line. Purpose: The available decay properties of proton drip-line nucleus $^{27}$S is insufficient to constrain the properties of the key resonance in $^{26}$Si$(p,\gamma)^{27}$P reaction rate and probe the possible isospin asymmetry. The decay scheme of $^{27}$S is complicated and far from being understood, which has motivated but also presented challenges for our experiment. Method: The $^{27}$S ions were implanted into a double-sided silicon strip detector array surrounded by the high-purity germanium detectors, where the $\beta$-delayed protons and $\gamma$ rays were measured simultaneously. Results: The improved spectroscopic properties including the precise half-life of $^{27}$S, the excitation energies, $\beta$-decay branching ratios, log~$ft$ values, and $B$(GT) values for the states of $^{27}$P populated in the $\beta$ decay of $^{27}$S were measured and compared to the $^{27}$Mg mirror states and the shell-model calculations. The present work has expanded greatly on the previously established decay scheme of $^{27}$S. Conclusions: The precise proton-separation energy of $^{27}$P, the energy and the ratio between $\gamma$ and proton partial widths of the $3/2^+$ resonance were obtained, thereby determining the $^{26}$Si$(p,\gamma)^{27}$P reaction rate based mainly on experimental constraints. The first evidence for the observation of a large isospin asymmetry for the mirror decays of $^{27}$S and $^{27}$Na is also provided. The experimental spectroscopic information can be reproduced by the shell-model calculation taking the weakly bound effect of the proton $1s_{1/2}$ orbit into account.

The cross sections of complete fusion and incomplete fusion for the $ ^{9} $Be + $ ^{197} $Au system, at energies not too much above the Coulomb barrier, were measured for the first time. The online activation followed by offline $\gamma$-ray spectroscopy method was used for the derivation of the cross sections. A slightly higher value of ICF/TF ratio has been observed, compared to other systems reported in the literature with $ ^{9} $Be beam. The experimental data were compared with coupled channel calculations without taking into account the coupling of the breakup channel, and experimental data of other reaction systems with weakly bound projectiles. A complete fusion suppression of about 40\% was found for the $ ^{9} $Be + $ ^{197} $Au system, at energies above the barrier, whereas the total fusion cross sections are in agreement with the calculations.

Two novel single crystal superalloys were designed to obtain affordable third generation single crystal superalloys. Creep tests and long-term thermal exposure were utilized to evaluate the microstructure and creep properties of the experimental alloys. Moreover, the role of Re in the microstructure and creep performance was investigated. Interestingly, the results showed that the two experimental alloys with different addition of Re demonstrated similar creep properties under the condition of 1120 degrees C/137 MPa. The alloy with 1 wt% Re owned much better microstructural stability for the rare presence of the TCP phase. However, With higher volume fraction of the gamma' phase and denser gamma/gamma' interfacial dislocation networks, the alloy with 2 wt% Re addition is believed to be provided with better precipitation strengthening and interfacial strengthening effects, which strongly guarantee the mechanical properties and hinder superdislocations shearing into the gamma' phase. Affected by the synergistic effects of their strengthening and weakening factors, the two experimental alloys exhibited few difference in creep rupture life under elevated-temperature and low stress condition. Important guidance for the further designs of single crystal alloys could be summarized from the present study.

Grain boundary character distribution (GBCD) of solution heat treated 2024 Al alloy was analyzed by electron backscattered diffraction, and intergranular corrosion (IGC) susceptibility and corrosion weight loss of the 2024 Al were investigated according to ASTM G110-92. The grain boundaries are composed of 12.17% low angle (Sigma 1) boundaries, 10.87% low coincidence site lattice (Sigma 3-Sigma 29) boundaries and 76.96% random (R) boundaries. After corrosion for 6 h, the corroded boundary proportions of Sigma 1, Sigma 3, Sigma 5-Sigma 29 and R boundaries were 10.71%, 11.11%, 21.95% and 25.14%, respectively. This shows that the GBCD has a great effect on IGC susceptibility of the solution treated 2024 Al, and both Sigma 1 and Sigma 3 boundaries exhibit much higher IGC resistance than Sigma 5-Sigma 29 and R boundaries. Among all the boundaries, the R boundaries have the highest IGC susceptibility.

The origin of Galactic $^{26}$Al is a long-standing question in nuclear astrophysics. The $^{26}$Si$(p,gamma)^{27}$P reaction has been thought to be important in the sequence that bypasses the production of this galactic $gamma$-ray emitter $^{26}$Al. Its reaction rate is dominated by a key $3/2^+$ proton resonance in $^{27}$P at the explosive hydrogen-burning temperature. However, the current recommended rate in REACLIB still has large uncertainties. In this work, the precise $beta$-decay spectroscopy of the drip-line nucleus $^{27}$S was studied by an implantation-decay method, where the $beta$-delayed protons and $gamma$ rays were measured simultaneously. We observed for the first time $beta$-delayed $gamma$ ray at 1125(2)~keV from $^{27}$S decay, corresponding to the and exit channel of the astrophysically important $3/2^+$ resonance in $^{26}$Si$(p,gamma)^{27}$P reaction. To date, the most precise proton-separation energy and mass excess of $^{27}$P is determined, and the ratio between $gamma$ and proton partial widths is pinned down experimentally for the first time. A precise thermonuclear $^{26}$Si$(p,gamma)^{27}$P rate is obtained based on these experimental observations. In the temperature region of $0.06sim0.3$~GK, the reaction rate is significantly lower than the recommended one, up to two orders of magnitude around 0.1~GK. The astrophysical impact of this new rate has been examined by the hydrodynamic simulations of novae outbursts, and it turns out that no significant change in the element production in the Mg-P mass region was found. The well-constrained rate effectively eliminates the uncertainty resulting from $^{26}$Si$(p,gamma)^{27}$P reaction in the model prediction of the nova contribution to the synthesis of Galactic $^{26}$Al.

Corrosion behaviors of pure Cu and Cu-Ni-Zn alloy were investigated in 3.5% NaCl solution and artificial seawater by electrochemical impedance spectroscopy and potentiodynamic polarization technologies, and the corrosion morphologies were observed by field emission scanning electron microscopy. The results revealed that Cu-Ni-Zn alloy possessed better corrosion resistance than that of pure Cu in both 3.5% NaCl solution and artificial seawater. The corrosion morphology displayed the corrosion product films on Cu-Ni-Zn alloy were more compact and uniform than that on the pure Cu in both 3.5% NaCl and artificial seawater media.