[en] High-spin states in the odd-proton nuclei ^119,121,123I and ^121,127,131Cs are studied following heavy-ion fusion-evaporation reactions using beams provided by the Stony Brook Tandem-LINAC accelerator. Gamma-rays resulting from deexcitations of high-spin states are measured using an array of six Compon-suppressed germanium detectors. Experiments performed include excitation functions, angular distributions, γ-γ coincidence and pulsed-beam E_γ-t measurements. Following theoretical predictions of competing prolate and oblate potential-energy minima, experimental evidence is presented for the coexistence of prolate and oblate nuclear shapes in ^119,121,123I. Both prolate and oblate rotational bands are observed with the same single-quasiproton configuration in each nucleus. Rotational bands in the Z = 55 Cs isotopes are found to be prolate at low spins. At higher spins, these nuclei possesses different shapes ranging from prolate to oblate, depending on the neutron number N. These shape differences result from the alignment of an h_11/2 neutron pair. The systematic behavior of neutron alignment is investigated. The change in the signature splitting and B(M1)/b(E2) ratios for bands below and above the alignment indicates that the shape changes are consistent with the γ-driving properties of h_11/2 neutrons. Finally, non-collective states are observed to become yrast at moderate spins in ¹¹⁹I and ¹²¹I

[en] Highlights: •The catalytic effect of TPP on the reaction of CNE and DOPO is revealed. •The reaction condition is determined by APC. •The decomposition mechanism of DOPO in air and nitrogen is proposed. •The flame-retardant mechanism of DOPO beneath or at the edge of flame is proposed. -- Abstract: Phosphorus-containing epoxy resins were synthesized by o-cresol-novolac epoxy resin (CNE) and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) catalyzed by triphenyl phosphine (TPP). The reaction was characterized by FTIR, differential scanning calorimeter(DSC), Advanced Polymer Chromatography (APC) and HCl/acetone titration method. The results showed that the reaction of CNE and DOPO completed in 2 h at 130 °C with 1.5%TPP and the activation energy reduced from 162 kJ/mol to113 kJ/mol. The thermal properties and flame retardancy of the phosphorus-containing epoxy resins cured by phenol formaldehyde novolac resin(PN) were investigated by simultaneous thermal analyzer, cone calorimeter, limiting oxygen index (LOI) and vertical burning test (UL-94). The results revealed that the DOPO groups decomposed into phosphoric or polyphosphoric acid in air and decomposed into PO free radicals in nitrogen. The epoxy thermoset with 1.5% phosphorus content achieved UL94 V-1 rating and LOI 27% and the epoxy thermoset with 2.4% phosphorus content achieved UL94 V-0 rating and LOI 31%. The morphology of residues after cone calorimeter test was observed by scanning electron microscope (SEM). The results showed that the char of DOPO-CNE(2%P)/PN and DOPO-CNE(3%P)/PN present a compact and continuous surface.

[en] Atherosclerotic plaque rupture is the leading cause of mortality in cardiovascular disease. Intravascular ultrasound (IVUS) imaging is a powerful clinical technique that provides real-time cross-sectional images of the arterial wall and atherosclerotic plaques. However, it does not provide sufficient information about the histological composition of plaques to characterize their vulnerability. Arterial wall strain measurements may provide insights into plaque composition and vulnerability, complementing the information directly available in the IVUS echogram. We have developed a method to measure the transverse arterial wall strain tensor in response to luminal pressure change, by registering IVUS images acquired at different pressures. This method has been validated by using IVUS images with simulated motion and IVUS images of a vessel phantom. In this study, we further evaluate the method by assessing the correspondence of the calculated strain distribution and the histological composition of atherosclerotic coronary arteries from Sinclair miniature pigs following 12 months of a high fat diet. The images were acquired in situ using a clinical IVUS system and under computer-controlled pressurization. After image acquisition, the artery segments were fixed for histology to identify plaque components. The strain distributions were aligned with the corresponding histological sections. The stiffness of various components of the lesion, inferred from the wall strain distribution, was consistent with the tissue composition seen in the histological cross-sections. These findings suggest that strain measurements from IVUS are promising for assessing plaque vulnerability.

[en] Intravascular ultrasound (IVUS) elastography is a promising tool for studying atherosclerotic plaque composition and assessing plaque vulnerability. Current IVUS elastography techniques can measure the 1D or 2D strain of the vessel wall using various motion tracking algorithms. Since biological soft tissue tends to deform non-uniformly in 3D, measurement of the complete 3D strain tensor is desirable for more rigorous analysis of arterial wall mechanics. In this paper, we extend our previously developed method of 2D arterial wall strain measurement based on non-rigid image registration into 3D strain measurement. The new technique registers two image volumes acquired from the same vessel segment under different levels of luminal pressure and longitudinal stress. The 3D displacement field obtained from the image registration is used to calculate the local 3D strain tensor. From the 3D strain tensor, radial, circumferential and longitudinal strain distributions can be obtained and displayed. This strain tensor measurement method is validated and evaluated using IVUS images of healthy porcine carotid arteries subjected to a luminal pressure increase and longitudinal stretch. The ability of the algorithm to overcome systematic noise was tested, as well as the consistency of the results under different longitudinal frame resolutions.

[en] Objective: To explore the feasibility of CTA in the coronary arteries with the double low technology, namely lowkV (100 kV) and low concentration of iodine wcontrast agent (270 mgI/ml). Methods: In the inclusion criteria, 100 patients with coronary artery CTA examination are divided into A, B two groups. Croup B again divided into B1 and B2 group according to the tube voltage and different iodine contrast agent. A group of 30 cases applied the prospective heart switch control, using 100 kV, 270 mgI/ml Visipaque contrast medium, group B applied retrospective heart switch control, including B1 group of 35 cases with 100 kV, 270 mgI/ml Visipaque contrast medium, B2 group of 35 cases with 120 kV, 370 mgI/ml Iopromide contrast agent. Finally, Calonlate the effective radiation dose of groups. Results: The mean effective dose (ED) in group A is (1.32 ± 0.012) mSv, B1 is (5.55 ± 1.04) mSv, B2 group is (10.57 ± 1.07) mSv. Between group A and group B1, group A and group B2 and B1 and B2 group, there is statistically significant. Conclusion: Under the condition of body mass index of ≤ 25.0 kg/m² or less, the application of double low technology, low kV (100 kV), low concentration of iodine contrast agent, can effectively reduce the radiation dose. (authors)

[en] Gold nanoparticles (AuNPs) were functionalized with the indicator dye Arsenazo III via reductive synthesis of AuNPs in the presence of arsenazo III. The indicator dye is shown to be immobilized on the AuNPs via interaction between gold and sulfo groups. The functionalized AuNPs undergo aggregation in the presence of uranyl ion due to the coordination interaction between arsenazo III and uranyl ion. This is accompanied by a longwave shift of the surface plasmon resonance absorption band (from 535 nm to 548 nm) and an up to 46.8 % increase in absorbance. This finding forms the basis for a photometric assay for uranyl ion. It shows good selectivity and has a 0.5 μM detection limit. Applied to the determination of uranyl ion in spiked environmental water samples, the recoveries were between 97 and 106 % (author)

[en] Highlights: • Dissociation behaviors of methane hydrate are studied in a Cuboid Pressure Vessel. • The combination of depressurization and electrical heating is employed and evaluated. • The use of electrical heating could enhance the gas production significantly. • The effects of key parameters on gas production are investigated. The gas production behaviors of methane hydrate dissociation induced by depressurization and electrical heating are investigated in a Cuboid Pressure Vessel (CPV) with an effective volume of 1.5 L. The vertical well located at the axis of the vessel is used as the production well, and a resistance heating wire is distributed uniformly in the inner surface of the well for heat injection. Hydrate samples with the similar phase saturations are prepared and then decomposed under depressurization and electrical heating. A total of five experimental runs have been carried out with different production pressure (3.50, 4.50, and 5.50 MPa) and electrical heating power (0, 25, and 50 W). It is found that methane hydrate can be dissociated continuously in the CPV in each run, which proves the feasibility of the used method for hydrate exploitation in porous media. Compared with the pure depressurization case (run 3), both the gas production and hydrate dissociation rates could be increased to a much higher level when a relatively slow heat injection rate is supplied from the well. In addition, the net energy E_net can be recovered with a much faster rate under constant electrical heating rate, and the final amount of E_net is only a little lower than that of run 3. They all indicate that the production efficiency of depressurization can be greatly enhanced by employing the electrical heating simultaneously. A maximum E_net can be obtained in each case with constant electrical heating, and it is suggested that the production process should be terminated before E_net begins to drop. The gas production performance is generally more favorable under lower production pressure and a higher electrical heating rate.

[en] The radon concentration is higher in the underground facilities than in the open space. In order to protect people who live or work in the underground space from radiation hazard, the radon reduction practice has become a necessity. Presently, active carbon radon adsorption technique and electric radon elimination technique are the two main techniques used in the radon reduction area. Active carbon adsorption device would take too much space and be high energy consumption when high efficiency was needed. Electric radon elimination technique had high efficiency in eliminating combined type radon decay products, but it had no influence on the concentration of radon and uncombined type radon decay products. Based on the present technique, metal-organic frameworks (MOFs) and membrane gas separation module were introduced and the possibilities of these new materials and technique were also analyzed. (authors)

[en] In this work, we re-analyze the Fermi-LAT observation of NGC 1275 to search for axion-like particle (ALP) effects and constrain ALP parameters. Instead of fitting the observed spectrum with ALP models, we adopt an alternative method for the analysis of this source which calculates the irregularity of the spectrum. With the newly used method, we find no spectral oscillation for the NGC 1275 and rule out couplings $g_{a\gamma }>3\times {10}^{-12}{\text{GeV}}^{-1}$ around ALP mass of $m_a\sim 1$ neV at 95% confidence level, which is more stringent than the previous results. We also show that the constraints can be further improved by combining the observation of PKS 2155-304. We suggest that with more sources taken into account, we could obtain a much wider exclusion region.

[en] The modeling of Li-Paczyński macronova/kilonova signals gives a reasonable estimate on the neutron-rich material ejected during the neutron star mergers. Usually the accretion disk is more massive than the macronova ejecta, with which the efficiencies of converting the disk mass into prompt emission of three merger-driven GRBs can hence be directly constrained. Supposing the macronovae/kilonovae associated with GRB 050709, GRB 060614, and GRB 130603B arose from radioactive decay of the r -process material, the upper limit on energy conversion efficiencies are found to be as low as ∼10"−"6–10"−"4. Moreover, for all three events, neutrino annihilation is likely powerful enough to account for the brief gamma-ray flashes. Neutrino annihilation can also explain the “extended” emission lasting ∼100 s in GRB 050709, but does not work for the one in GRB 060614. These progresses demonstrate that the macronova can serve as a novel probe of the central engine activity.