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Background: We sought to investigate epidemiologic features of Kawasaki disease (KD) in Shanghai from 2013 through 2017 and identify risk factors for coronary artery lesions (CAL). Methods: As in our previous three surveys, a set of questionnaires and diagnostic guidelines for KD were sent to 50 hospitals providing pediatric medical care in Shanghai. Medical records of KD patients diagnosed from January 2013 through December 2017 were retrospectively analyzed. Multivariate logistic regression analysis was performed to identify risk factors for CAL. Results: A total of 4,452 cases were enrolled. Male-to-female ratio was 1.7:1. The incidence of KD was 68.8 to 107.3 per 100,000 children aged 10 days, were independently associated with CAL. Conclusions: The incidence of KD in Shanghai had substantially increased while the proportion of CAL had substantially decreased as compared with our previous surveys. Higher platelet levels, lower albumin levels, male sex, incomplete KD, IVIG resistance, and receiving initial IVIG ≤4 days or >10 days, were risk factors for CAL.

The mass dependence of the transverse flow for $Z=1$--5 fragments from the collisions of $^{40}\mathrm{Ar}+^{27}\mathrm{Al}, ^{40}\mathrm{Ar}+^{48}\mathrm{Ti}$, and $^{40}\mathrm{Ar}+^{58}\mathrm{Ni}$ at 47 MeV/nucleon is investigated experimentally in this article. The transverse flow values are determined using the in-plane components of the fragment transverse momenta, where three conventional methods, i.e., the kinetic flow tensor method, the transverse momentum analysis method, and the azimuthal correlation method, are applied to reconstruct the reaction plane in an event-by-event basis. It is demonstrated from the comparison of the present experimental mass dependent flow measurements and the model simulations using an improved antisymmetrized molecular dynamics model that the experimentally observed abnormal $\ensuremath{\alpha}$ transverse flow enhancement is closely related to the reaction plane reconstruction procedure in the flow extraction. We further investigate the physical existence of the abnormal $\ensuremath{\alpha}$ flow behavior using a two-particle azimuthal correlation method, which allows us to provide the relative flow magnitude information with an identification of fragment charge number without the knowledge of the reaction plane differing from the three conventional methods. It is found that the relative flow magnitudes deduced from the two-particle azimuthal correlation functions with an identification of $Z$, with the correction for the recoil effect imposed by the momentum conservation, show a monotonically increasing trend as a function of fragment charge number, with no exception of the $\ensuremath{\alpha}$ flow enhancement. These results, in addition to those from the improved antisymmetrized molecular dynamics model simulations, definitely provide experimental evidences for the inexistence of the abnormal $\ensuremath{\alpha}$ flow behavior in the heavy-ion collisions at the present incident energy region in nature.

To study the β -delayed neutron decay of nuclei far from β stability line, a new β -delayed neutron detection system working with the continuous beam mode has been built at Peking University and tested with radioactive ion beams . To get fast timing signal for neutron Time-of-Flight (ToF) measurement and good spatial correlation between the implanted particles and the subsequent β particles, a double-sided silicon detector is sandwiched between two thin plastic scintillators , which constitute the implantation and β detection array. According to the test measurements with radioactive ion beams, this detection system has a high β coincident detection efficiency of 30 . 7 ( 5 ) % with much less disturbance from other unstable nuclei and the random background. After the time-walk correction and the flight path calibration, good energy resolution based on neutron ToF measurement can be obtained. The properties of this detection system make the study of β -delayed neutron decay of nuclei with very low beam intensity feasible.

A systematic program of investigations of nuclear reactions in laser-produced plasmas is addressed. Such reactions provide an important diagnostic tool for probing the dynamics and thermodynamics i...

Conductive and fluorescent hollow micro/nanospheres have attracted great attention owing to their potential applications such as environmental clean-up, energy storage, sensors, and medical diagnosis. We report novel, tunable, and uniform hollow microspheres of conjugated poly(aniline-co-3-amino-9-ethyl-carbazole) (PAC) copolymer synthesized by a template-free method, namely a simple chemical oxidative copolymerization of aniline and 3-amino-9-ethyl-carbazole. The molecular structure of the copolymers has been systematically characterized by UV–vis, ATR-IR, Raman, and solid-state 13C cross-polarization magic angle spinning NMR spectroscopies. The particle size and properties including dispersibility, thermostability, electrical conductivity, fluorescence emission and its sensitive quenching of PAC hollow microspheres can be significantly controlled by simply optimizing feed comonomer ratios and reaction parameters such as acidic media and oxidants used. The formation mechanism of PAC hollow microspheres and their sensitively and selectively sensing properties toward nitro-based explosives and Cu(II) ions with the limit of detection down to 5 μM and 5 nM are demonstrated, respectively. In particular, the limit of detection for Cu2+ is superior as compared to literature reports.

It remains a great challenge to cost-efficiently and cleanly synthesize sustainable polyesters based on both biomass-derived comonomers and biogenic catalysts because of the lack of clean, biogenic, and active catalysts so far. This work would like to address the tough problems of cleaner manufacturing and processing of the polyesters. We report the first example of the sustainable copolyesters from starch-based isosorbide/ethylene glycol and terephthalic acid by a highly active but environmentally benign Ti-Mg catalyst designed in our laboratory replacing current toxic catalysts. The optimal content of the Ti-Mg catalyst for productively synthesizing the copolyesters is down to 5 ppm that is just 1/30–1/75 content of traditional toxic catalysts including Sb2O3, GeO2, and pyridine reported heretofore. The copolyesters obtained by the Ti-Mg catalyst possess higher molecular weight up to Mn 25150, better performance, and are much more environmentally benign than most of similar copolyesters reported up to now. The copolyesters retain transparency owing to their irregular chain structure and random chain sequence and thus remain as a stable amorphous structure even after experiencing heating/cooling cycles. The Ti-Mg catalyst demonstrates 41–46 times higher catalytic activity than Sb2O3 catalyst and is active enough to catalyse the direct polycondensation between OH and COOH by eliminating water that is clearly distinguished from toxic methanol and corrosive HCl produced by polycondensation between OH and COOCH3/ COCl catalyzed with toxic Sb2O3/pyridine catalysts, achieving cost-efficient and cleaner synthesis of the copolyesters without toxic residues. A systematic environmental analysis of the Ti-Mg catalyst, the copolyesters, raw materials and catalytic process, has been estimated, signifying that the Ti-Mg catalyst replacing current Sb2O3, GeO2, and pyridine accomplishes the cleaner production of most polyesters without toxic discharge or other harmful environmental impacts.

$^{6}$He+$t$ cluster states of exited $^{9}$Li have been measured by 32.7 MeV/nucleon $^{9}$Li beams bombarding on $^{208}$Pb target. Two resonant states are clearly observed with the excitation energies at 9.8 MeV and 12.6 MeV and spin-parity of 3/2$^{-}$ and 7/2$^{-}$ respectively. These two states are considered to be members of K$^{\pi}$=1/2$^{-}$ band. The spin-parity of them are identified by the method of angular correlation analysis and verified by the continuum discretized coupled channels (CDCC) calculation, which agrees with the prediction of the generator coordinate method (GCM). A monopole matrix element about 4 fm$^{2}$ for the 3/2$^{-}$ state is extracted from the distorted wave Born approximation (DWBA) calculation. These results strongly support the feature of clustering structure of two neutron-rich clusters in the neutron-rich nucleus $^{9}$Li for the first time.

Nuclear liquid-gas phase transitions are investigated in the framework of static antisymmetrized molecular dynamics (static AMD) model under either a constant volume or a constant pressure. A deuteron quadrupole momentum fluctuation thermometer is applied to extract the temperature of fragmenting systems of $^{36}$Ar and $^{100}$Sn. A plateau structure of caloric curves is observed under a constant volume for those system with a density $\rho \leq$ 0.03 fm$^{-3}$. A clear backbending in the caloric curves, which indicates a first order phase transition, is observed under a constant pressure with all pressures studied. The similar behavior of caloric curves of $^{36}$Ar and $^{100}$Sn systems indicates that there is no strong system size effect under a constant volume or a constant pressure. Both the mass distributions and the light particle multiplicities show a strong $\alpha$ clusterization at low excitation energies in the static AMD simulations. The liquid-gas phase transition measures of the multiplicity derivative (dM/dT) and the normalized variance of $Z_{max}$ (NVZ) are applied. The experimental caloric curves are also compared with those of $^{100}$Sn of the static AMD simulations under both the constant volume and the constant pressure conditions. Discussions are presented with the available experimental results and those from the static AMD simulations. Large errors in the experimental temperature measurements and those in the reconstruction technique for the primary fragmenting source hinder to draw a conclusion whether the phase transition occurs under either a constant volume or a constant pressure. This study suggests that different measures for the liquid-gas phase transitions should be examined besides the caloric curves in order to draw a conclusion., Comment: 10 figures

The experimentally observed abnormal $\ensuremath{\alpha}$ flow behavior from heavy-ion collisions at intermediate energies is investigated using the events of $^{40}\mathrm{Ca}+^{40}\mathrm{Ca}$ at 35 MeV/nucleon simulated with an improved antisymmetrized molecular dynamics model with specific consideration of the Fermi motion in the nucleon-nucleon collision process. Its possible origins in the processes from the fragment formation to the experimental flow extraction, i.e., dynamical process, sequential decay, experimental detection, and data analysis, are closely examined. It is found that the observed abnormal $\ensuremath{\alpha}$ flow behavior originates from the reconstruction of reaction planes in the flow extraction. How the abnormal $\ensuremath{\alpha}$ flow behavior is generated from the reaction plane reconstruction procedure is discussed.

Albergo thermometers with double isotope, isotone, and isobar yield ratio pairs with one proton and/or neutron difference are investigated. Without any extra sequential decay correction, a real temperature value of $4.9\ifmmode\pm\else\textpm\fi{}0.5$ MeV is deduced from the yields of the experimentally reconstructed primary hot intermediate mass fragments (IMFs) from $^{64}\mathrm{Zn}+^{112}\mathrm{Sn}$ collisions at 40 MeV/nucleon using the Albergo thermometer for the first time. An experimental sequential decay correction from the apparent temperatures to the real ones for 12 other reaction systems with different neutron-proton ($N/Z$) asymmetries in the same experiment, $^{70}\mathrm{Zn}$, $^{64}\mathrm{Ni}$ on $^{112,124}\mathrm{Sn}$, $^{58,64}\mathrm{Ni}$, $^{197}\mathrm{Au}$, and $^{232}\mathrm{Th}$ at 40 MeV/nucleon, is performed using an empirical correction factor approach of Tsang et al. [Phys. Rev. Lett. 78, 3836 (1997)] with the deduced 4.9-MeV temperature value. The dependence of nuclear temperature on the source $N/Z$ asymmetry is further investigated using these deduced real source temperature values from the present 13 systems. It is found that the deduced real source temperatures at the present source $N/Z$ range show a rather weak dependence on the source $N/Z$ asymmetry. By comparison between our previous results and those from other independent experiments, a consistent description for the $N/Z$ asymmetry dependence of nuclear temperature is addressed.

It remains great challenges to fabricate advanced potentiometric sensors based on ion-selective electrodes (ISEs) with ultrasensitivity, high selectivity, long-term durability, and even reproducible potential. Sensing and transducing materials are vital components for substantial performance optimization. This review systematically summarizes the progress in ionophore, formulation, preparation, nanostructure, and electrochemical properties of state-of-the-art sensing membranes and ion-to-electron transducing layers for comprehensively stabilizing potential and enhancing the sensing performance. This article elaborates the development of cutting-edge solid-contact (SC)-ISEs including wearable chip and needle electrodes to achieve versatile applications like health and environmental monitorings, medical diagnosis, food and plant analysis. As an indispensable element in SC-ISEs, the transducing materials particularly including conducting polymers, noble metals and carbon nanomaterials for stabilizing potential are thoroughly expounded. It is suggested that the highly transducing materials with practical applicability should possess two key features including high hydrophobicity and strong adherence onto the electrode substrates and ion-selective membranes besides high ion and electron conductivity, which could be used to guide the design and fabrication of next-generation ISEs based on multifeatured composites. The current startup status and future research direction of calibration-free ISEs with excellent potential reproducibility that would become a major hotspot in the field soon are highlighted.

β-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of β-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror β decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

X. G. Cao, E. J. Kim, K. Hagel, M. Barbui, J. Gauthier, S. Wuenschel, G. Giuliani, M. R. D. Rodriguez, H. Zheng, M. Huang, A. Bonasera, R. Wada, N. Blando, G. Q. Zhang, C. Y. Wong A. Staszczak, Z. X. Ren, Y. K. Wang, S. Q. Zhang, J. Meng, J. B. Natowitz, Exclusive measurements for α and α conjugate exit channels are carried out for 35 MeV/nucleon 28Si induced reactions. Systematic analyses of these channels reveal high energy resonance structures in 7 de-excitation channels. The resonances are compared with results of several recent theoretical calculations for toroidal high-spin isomers. The possible underlying physics of these observations are discussed.

Investigating deuteron–deuteron (DD) fusion reactions in a plasma environment similar to the early stages of the Big Bang is an important topic in nuclear astrophysics. In this study, we experimentally investigated such reactions, using eight laser beams with the third harmonic impacting on a deuterated polyethylene target at the ShenGuang-II Upgrade laser facility. This work focused on the application of range-filter (RF) spectrometers, assembled from a 70 μm aluminum filter and two CR-39 nuclear track detectors, to measure the yields of primary DD-protons. Based on the track diameter calibration results of 3 MeV protons used to diagnose the tracks on the RF spectrometers, an approximate primary DD-proton yield of $$(8.5\pm 1.7)\times 10^6$$ was obtained, consistent with the yields from similar laser facilities worldwide. This indicates that the RF spectrometer is an effective way to measure primary DD-protons. However, due to the low yields of $${\hbox {D}}^{3}{\mathrm {He}}$$-protons and its small track diameter, CR-39 detectors were unable to distinguish it from the background spots. Using other accurate detectors may help to measure these rare events.

The poly(ester-co-ether)s (PEEs) comprising poly(butylene terephthalate) and poly(tetramethylene glycol) (PTMG) segments were cost-efficiently synthesized by direct esterification of terephthalic acid (TPA) and 1,4-butandiol (BDO)/PTMG with Mn of 1000 in one feeding step by a unique nontoxic Zr–Mg catalyst that is designed and synthesized in our laboratory, avoiding undesirable eco-hazardous cocatalyst and byproducts that must be produced when terephthaloyl chloride (TPC) and dimethyl terephthalate (DMT) were chosen. The structure of the Zr–Mg catalyst and PEEs was systematically analyzed by high-resolution 1H NMR, ATR-FTIR spectroscopies, and X-ray diffraction. The size-exclusion chromatography suggested that the weight-average molecular weight of the PEEs reaches up to 60 600 g/mol. In particular, the ether-segment retention, molecular weight, melt processability, and mechanical properties of the PEEs are significantly higher by Zr–Mg catalyst than by Ti–Mg and traditional tetrabutyl titanate (TBT) cata...

Two types of wedge-shaped CsI(Tl) crystals were designed to be placed behind an annular double-sided silicon detector to identify light charged-particles with the Δ E − E method. The properties of the CsI(Tl) detectors with different shapes and sizes were investigated using an α source and a radioactive beam of 15C. The larger crystal was found to have better energy resolution, smaller light output non-uniformity, as well as better particle identification capability, and was finally adopted to form the Δ E - E telescope. The performance of the two types of CsI(Tl) crystals are interpreted based on Geant4 simulation results.

In the integral benchmark experiment presented here, an aluminium (Al) slab sample (300 mm × 300 mm × 100 mm) was irradiated with Deuterium-Tritium (D-T) fusion neutrons. The neutrons leaking from the sample were detected by a BC501A organic liquid scintillator through the time-of-flight (TOF) method; the neutron energy spectra were derived from the as-obtained TOF curves by considering the detector efficiency. For comparison, some leakage neutron spectra were also simulated by combining a Monte Carlo neutron transport code with evaluated nuclear data from the ENDF/B-VIII.0, JENDL-4.0 and CENDL-3.1 libraries. All the calculated values agreed with the experimental data within 10%, except for a few energy ranges. The values predicted using the ENDF/B-VIII.0 library were lower and higher than the measured ones at below and higher above 4 MeV, respectively; the data based on the CENDL-3.1 and JEDNL-4.0 libraries exhibited some larger differences in the 9.5–12 MeV range at 120 ∘ . The possible causes of these discrepancies are also discussed.

The traditional isoscaling technique has been used to analyze all isotopically identified particles from 70 Zn+ 70 Zn and 64 Zn+ 64 Zn collisions at 35 MeV/u. Two additional techniques, using an energy-averaged ratio and using the data present in the tail of energy spectra, are compared to the traditional method and show similar results. Isoscaling fit parameters α and β are found both globally and for each individual series of constant Z and N . The data are then split up between emitted fragments and projectile-like fragments. Isoscaling values for the two different types of fragments are shown to be different, emphasizing the importance of experimentally distinguishing between projectile-like fragments and emitted fragments in order to achieve accurate isoscaling parameters.

Efficient sustainable synthesis of high-performance poly(trimethylene terephthalate) (PTT) with simultaneously high molecular weight, narrow molecular weight distribution, and tiny cyclic dimer suitable for high end applications at low cost still faces challenges. Novel nontoxic and 1,3-propanediol-soluble Ti/Mg bimetal catalyst mainly based on biobased 1,3-propanodiol and food grade materials has been productively synthesized and also carefully characterized. The Ti/Mg catalyst was found to be exceptionally active catalysts for the polycondensation of terephthalic acid and 1,3-propanediol from a renewable resource capable of producing high-molecular-weight PTT as an environmentally friendly and recyclable material in both laboratory reactor and continuous pilot plant. The high-quality PTT samples with the highest number-average molecular weight up to 68 870 g/mol ever reported so far, the narrowest molecular weight distribution index down to 1.92, and the second lowest cyclic dimer content down to 2.21% ...

The dependence of the nuclear temperature on the source neutron-proton ($N/Z$) asymmetry is experimentally investigated with the intermediate mass fragments (IMFs) generated from thirteen reaction systems with different $N/Z$ asymmetries, $^{64}\mathrm{Zn}$ on $^{112}\mathrm{Sn}$ and $^{70}\mathrm{Zn}, ^{64}\mathrm{Ni}$ on $^{112,124}\mathrm{Sn}, ^{58,64}\mathrm{Ni}, ^{197}\mathrm{Au}, ^{232}\mathrm{Th}$ at 40 MeV/nucleon. The apparent source temperatures for these systems are determined from the measured IMF yields from the intermediate velocity sources using eight carbon-related double isotope ratio thermometers. A rather weak $N/Z$ asymmetry dependence of the source temperature is qualitatively inferred from the extracted $N/Z$ asymmetry dependence of the apparent temperature and that of the relative temperature change by the sequential decay effects with the help of the theoretical simulations. The present result is compared with those from other available experiments.

A systematic study of system size, $N/Z$ asymmetry, and fragmenting volume effects as well as the Coulomb effect on experimental measures for the nuclear liquid-gas phase transition and the mechanism of phase transition are carried out in the framework of the statistical multifragmentation model (SMM). The measures examined here are the caloric curve, the specific heat capacity (${C}_{v}$), the multiplicity derivative ($dM/dT$), the moment parameters (${M}_{2}$ and ${\ensuremath{\gamma}}_{2}$), the fluctuation of maximum fragment charge number (NVZ), the Fisher exponent ($\ensuremath{\tau}$), and the Zipf's law parameter ($\ensuremath{\xi}$). A signal for the first-order phase transition for all the measures is observed. A stronger signal is observed in the system with smaller sizes or with more neutron rich or in smaller fragmenting volumes for the caloric curve, ${C}_{v}$, and $dM/dT$. The phase-transition temperatures are independent of the system size, $N/Z$ asymmetry, fragmenting volume, and Coulomb force, which indicates these measures give a solid signal for the liquid-gas phase transition in SMM. On the other hand, the phase transition temperature and its behavior of the others slightly depend on the size, the $N/Z$ asymmetry and the volume of the system. A negative heat capacity is observed for systems with ${A}_{s}\ensuremath{\ge}$ 100 without the Coulomb force but disappears with the Coulomb. An instructive picture is given in the charge distributions for the observed first-order phase transition.

Poly(1,5-diaminonaphthalene) microparticles with abundant reactive amino and imino groups on their surface were synthesized by one-step oxidative polymerization of 1,5-diaminonaphthalene using ammonium persulfate as the oxidant. The molecular, supramolecular, and morphological structures of the microparticles were systematically characterized by IR and UV-vis spectroscopies, elementary analysis, wide-angle X-ray diffractometry, and transmission electron microscopy. The microparticles demonstrate electrical semiconductivity and high resistance to strong acid and alkali, and strong adsorption capability for lead(II), mercury(II), and silver(I) ions. The experimental conditions for adsorption of Pb(II) were optimized by varying the persulfate/monomer ratio, adsorption time, sorbent concentration, and pH value of the Pb(II) solution. The maximum adsorption capacity is 241 mg·g−1 for particles after a 24 h-exposure to a solution at an initial Pb(II) concentration of 29 mM. The adsorption data fit a Langmuir isotherm and follow a pseudo-second-order reaction kinetics. This indicates a chemical adsorption that is typical for a chelation interaction between Pb(II) and amino/imino groups on the sorbent.

The experimental excitation function for the $7\ensuremath{\alpha}$ de-excitation of $^{28}\mathrm{Si}$ nuclei excited to high excitation energies in the collisions of 35 MeV/nucleon $^{28}\mathrm{Si}$ with $^{12}\mathrm{C}$ reveals resonance structures. The possibility that these structures may indicate the population of toroidal high-spin isomers such as those predicted by a number of recent theoretical calculations is discussed and the need for further investigations is emphasized.

The neutron yield in $^{12}$C(d,n)$^{13}$N and the proton yield in $^{12}C(d,p)^{13}$C have been measured by deuteron beam from 0.6 MeV to 3 MeV which is delivered from a 4-MeV electro static accelerator bombarding on the thick carbon target. The neutrons are detected at $0\degree$, $24\degree$, $48\degree$ and the protons at $135\degree$ in the lab frame. The ratios of the neutron yield to the proton one have been calculated and can be used as an effective probe to pin down the resonances. The resonances are found at 1.4 MeV, 1.7 MeV, 2.5 MeV in $^{12}C(d,p)^{13}$C and at 1.6 MeV, 2.7 MeV in $^{12}$C(d,n)$^{13}$N. This method provides a way to reduce the systematic uncertainty and helps to confirm more resonances in compound nuclei., Comment: 7 pages, 2 tables, 6 pages; submitted to Nuclear Science and Techniques (http://link.springer.com/journal/41365)

Heavy ion collisions near the Fermi energy produce a ‘freezout’ region where fragments appear and later decay, emitting mainly neutrons, protons, alpha particles, and gamma rays. These decay products carry information about the decaying nuclei. Fragmentation events may result in high yields of boson particles, especially alpha particles, and may carry important information about the nuclear Bose Einstein condensate (BEC). We study ‘in medium’ four α correlations and link them to the ‘fission’ of 16O in two 8Be in the ground state or 12C*(Hoyle state)+α. Using novel techniques for the correlation functions, we confirm the resonance of 16O at 15.2 MeV excitation energy, and the possibility of a lower resonance, close to 14.72 MeV. The latter resonance is the result of all α particles having 92 keV relative kinetic energies.

Scalable and transparent polyether-based waterborne polyurethane (WPU) thin films that adhere firmly to Al nanofilm but not to PET film without release agents have been designed and prepared. In order to realize cleaner production, eco-friendly acetyl tributyl citrate (ATBC) instead of toxic additives like N-methylpyrrolidone was introduced into polymerization system as both an effective dispersant of dimethylolpropionic acid crystal as hydrophilic chain extender and a viscosity thinner of the synthesized precursors to promote homogeneous hydrophilic extension reaction in the absence of toxic catalysts. The appropriate ATBC and dimethylolpropionic acid contents are critical to formation of stable translucent dispersion of the WPU with total hard segments as high as 56 wt% at –NCO/-OH molar ratio of 1.05. Molecular structure and ATBC existence of the WPU film have been characterized by IR, NMR, gas chromatography, and thermogravimetry, suggesting that ATBC will not release into the environment even if at 140 °C because of its high boiling point and ultralow volatility. The reserved ATBC in the WPU film also acts as an effective plasticizer and lubricant so that the WPU film can be quickly peeled off from PET. The lowest T-peel strength of 1.3 N m−1 on PET is achieved for the WPU film with a high tensile strength of 15.8 MPa and a medium elongation at break of 237%. The WPU films have tunable stickiness onto PET film from sticky to completely nonsticky. Importantly, the WPU films offer simultaneously strong adhesion to Al nanofilm and high thermal stability but high peelability from the PET, allowing to fabricate a stable holographic/photolithographic composite film by Al deposition at >1000 °C and ensure high flatness and luster of the composite film. Optimal formulations of WPU materials with high comprehensive performance including good film-processability, ultralow VOC emission, high mechanical and thermal properties, controllable surface tension, and tunable adhesion to Al nanofilm have been proposed for transferable holographic films.

Poly(m-phenylenediamine) (PmPD) microspheres were productively and sustainably synthesized by a facile one-step chemical oxidative polymerization of m-phenylenediamine with ammonium persulfate in pure water without any acid or alkali. A comprehensive characterization of the structures, morphology, and nature of PmPD microspheres suggested that they exhibited highly chemical/thermal resistance and strong Hg(II) adsorbability. The batch static sorption/desorption of mercury ions were systematically optimized by adjusting the sorption/desorption time and temperature, mercury-ion concentration, sorbent dosage, and the species, concentration and dose of desorbents. The microparticles exhibit high Hg(II) sorption capacity up to 1499.2 mg/g at an initial Hg(II) concentration of 1986 mg/L, high Hg(II) partition coefficient up to 5040 mg/(g.μM) at an initial Hg(II) concentration of 20 mg/L, and high initial sorption rate up to 763.3 mg/(g.min). The dynamic sorption results suggest that the breakthrough and saturation times of the column loaded with the microparticles toward 1.99 mM Hg(II) solution at the flow rate of 1 mL/min are 19.8 h and 58.0 h, respectively. After 5 dynamic sorption-desorption cycles, the column efficiency is still high, indicating good reusability. A sorption mechanism including the first reduction from mercury-ion to mercurous-ion by amino and imino groups, and the second complexation and ion exchange of mercurous-ions is proposed. Without the pollution caused by the preparation or part solubility of sorbents themselves, the PmPD microspheres are cost-effectively and eco-benignly applicable to elimination and recovery of mercury ions in wastewater. This generates a unique solution to sustainable problems of sorbents themselves.

The $\beta$ -delayed particle emission from 21Mg was studied at the Radioactive Ion Beam Line in Lanzhou (RIBLL1). Silicon array and high-purity germanium (HPGe) detectors were used to detect the charged particles and $\gamma$ -rays emitted from the decay. Half-life time of 21Mg was determined to be 121.9(6) ms. New levels (5.639(26) MeV and 6.644(34) MeV) in the nucleus 21Na were observed. An improved proton spectrum coincident with $\gamma$ -rays at 1.633 MeV was obtained. A new partial decay scheme was constructed based on the present measurement.

In this paper, the implantation-decay method is introduced to study the $$\beta $$ -delayed charged particle decay. A silicon detector array was used for the implantation of the incident beams and for the detection of the emitted particles. An experimental measurement on the $$\beta $$ -delayed particle emission from $$^{22}$$ Al was used to demonstrate the method. The half-life value, charged particle spectroscopy, $$\gamma $$ ray spectrum, and $$\gamma $$ particle coincidence for the decay process were obtained and compared with previous experimental results for $$^{22}$$ Al. The results show that the implantation-decay method, using a silicon detector array, is a suitable experimental method to study the $$\beta $$ -delayed charged particle decay for proton-rich nuclei.

The experimental measures of the multiplicity derivatives---the moment parameters, the bimodal parameter, the fluctuation of maximum fragment charge number (normalized variance of ${Z}_{\mathrm{max}}$, or NVZ), the Fisher exponent ($\ensuremath{\tau}$), and the Zipf law parameter ($\ensuremath{\xi}$)---are examined to search for the liquid-gas phase transition in nuclear multifragmention processes within the framework of the statistical multifragmentation model (SMM). The sensitivities of these measures are studied. All these measures predict a critical signature at or near to the critical point both for the primary and secondary fragments. Among these measures, the total multiplicity derivative and the NVZ provide accurate measures for the critical point from the final cold fragments as well as the primary fragments. The present study will provide a guide for future experiments and analyses in the study of the nuclear liquid-gas phase transition.

The quasielastic scattering angular distribution of 17C from a carbon target at 40MeV/nucleon was measured using the inverse kinematics method. The analysis of the experimental data was started using the optical model. The data were reproduced very well and the optical potential in the Woods-Saxon form was obtained. Within the framework of the coupled-channel method, the contribution from the inelastic channels to the experimental data is found significant at large angles. A systematic analysis of the elastic/quasielastic scattering of 11-13,17C + 12C was performed as well. The present work indicates that 17C is a normal nucleus whose radius is not anomalously large.

In this article, a mistake in the formulation of the modified Fisher model (MFM) derived in the pioneering works of the Purdue group is addressed and corrected by reversing the sign of the mixing entropy term in the original formulation. The errors in the results of the previous MFM-related studies, such as isotopic yield distribution, isobaric yield ratios, isoscaling, $m$ scaling, self-consistent determination of density, symmetry energy, and temperature, and density and temperature determination related to the intermediate mass fragment (IMF) freezeout, are quantitatively analyzed. It is found that the errors originating from the mistake in sign of the mixing entropy term are generally small and even have no effect in some cases.

When two heavy ions near the Fermi energy collide, a warm and low-density region can form in which fragments appear. This region is mainly dominated by proton (p) and alpha particles. In such an environment, the alphas interact with each other, and especially through strong resonances, form complex systems such as 8Be and 12C. Our experiments show that in the reactions 70(64)Zn(64Ni)+70(64)Zn(64Ni) at E/A=35 MeV/nucleon levels of 8Be appear around relative energies Eij=0.092 MeV, 3.03 MeV as well as above 10 MeV and 100 MeV. For the 3 alpha systems, multi resonance processes give rise to excited levels of 12C. In particular, the Hoyle state at 7.654 MeV excitation energy shows a decay component through the ground state of 8Be and also shows components where two different alpha couples are at relative energies consistent with the ground state of 8Be at the same time. A component where the three alpha relative energies are consistent with the ground state of 8Be (i.e., E12=E13=E23=0.092 MeV) is also observed at the 7.458 MeV excitation energy, which was suggested as an Efimov state., Comment: 8 pages, 5 figures

Resonance structures are observed in the excitation function of the 7α de-excitation of 28Si nuclei are observed in the collisions of 35 MeV/nucleon 28Si with 12C. These structures may indicate that toroidal high-spin isomers such as those predicted by recent theoretical calculations are populated.

Benchmarking of evaluated nuclear data libraries was performed for $\sim 14.8$ MeV neutrons on Gallium targets. The experiments were performed at China Institute of Atomic Energy(CIAE). Solid samples of natural Gallium (3.2 cm and 6.4 cm thick) were bombarded by $\sim 14.8$ MeV neutrons and leakage neutron energy spectra were measured at 60$^{\circ}$ and 120$^{\circ}$. The measured spectra are rather well reproduced by MCNP-4C simulations with the CENDL-3.1, ENDF/B-VII and JENDL-4.0 evaluated nuclear data libraries, except for the inelastic contributions around $E_{n} = 10-13$ MeV. All three libraries significantly underestimate the inelastic contributions. The inelastic contributions are further studied, using the Talys simulation code and the experimental spectra are reproduced reasonably well in the whole energy range by the Talys calculation, including the inelastic contributions., Comment: 12 pages, 7 figures

Symmetry energy, temperature and density at the time of the intermediate mass fragment formation are determined in a self-consistent manner, using the experimentally reconstructed primary hot isotope yields and anti-symmetrized molecular dynamics (AMD) simulations. The yields of primary hot fragments are experimentally reconstructed for multifragmentation events in the reaction system Zn 64 + Sn 112 at 40 MeV / nucleon . Using the reconstructed hot isotope yields and an improved method, based on the modified Fisher model, symmetry energy values relative to the apparent temperature, a sym / T , are extracted. The extracted values are compared with those of the AMD simulations, extracted in the same way as those for the experiment, with the Gogny interaction with three different density-dependent symmetry energy terms. The a sym / T values change according to the density-dependent symmetry energy terms used. Using this relation, the density of the fragmenting system is extracted first. Then symmetry energy and apparent temperature are determined in a self consistent manner in the AMD model simulations. Comparing the calculated a sym / T values and those of the experimental values from the reconstructed yields, ρ / ρ 0 = 0.65 ± 0.02 , a sym = 23.1 ± 0.6 MeV and T = 5.0 ± 0.4 MeV are evaluated for the fragmenting system experimentally observed in the reaction studied.

A novel polyfluoranthene (PFA) exhibiting strong visual fluorescence emission, a highly amplified quenching effect, and widely controllable electrical conductivity is synthesized by the direct cationic oxidative polymerization of fluoranthene in a dynamic interface between n-hexane and nitromethane containing fluoranthene and FeCl3, respectively. A full characterization of the molecular structure signifies that the PFAs have a degree of polymerization from 22–50 depending on the polymerization conditions. A polymerization mechanism at the interface of the hexane/nitromethane biphasic system is proposed. The conductivity of the PFA is tunable from 6.4 × 10−6 to 0.074 S cm−1 by doping with HCl or iodine. The conductivity can be significantly enhanced to 150 S cm−1 by heat treatment at 1100 °C in argon. A PFA-based chemosensor shows a highly selective sensitivity for Fe3+ detection which is unaffected by other common metal ions. The detection of Fe3+ likely involves the synergistic effect of well-distributed π-conjugated electrons throughout the PFA helical chains that function as both the fluorophore and the receptor units.

Strongly fluorescence-emitting oligofluoranthene nanorods efficiently synthesized by template-free oligomerization of fluoranthene in nitromethane demonstrate tunable conductivity and porous carbon formability., Strongly fluorescence-emitting oligofluoranthene (OFA) nanorods are readily synthesized by a direct template-free chemical oxidative oligomerization of fluoranthene in nitromethane containing ferric chloride as an oxidant. The OFAs likely consist of five fluoranthene units containing cyclic pentamers with crystalline order and tunable electrical conductivity across 12 orders of magnitude. The OFA nanorods are heat-resistant materials and efficient precursors for macroporous carbon materials with high carbon yield in argon at 1100 °C. In particular, the optimal ring-like pentamer shows 12.2 times stronger cyan fluorescence-emission than recognized highly fluorescent fluoranthene under the same conditions, which makes the OFAs into ideal strong fluorescent emitters, tunable conductors, and high carbon-yield precursors for the preparation of sensors and carbon materials. These findings demonstrate an advance in the direct synthesis of oligomers from fused-ring aromatic hydrocarbons and provide a potential direction to optimize the synthesis and functionalities of wholly aromatic nanomaterials.

The breakup reaction of $$^{9}\hbox {Li}$$ on a Pb target has been measured at 32.7 MeV/nucleon for the first time. Two peaks of $$^{6}\hbox {He}+\hbox {t}$$ coincident fragments at 9.8 and 12.5 MeV were observed and agreed with the results of the generator coordinate method calculation. The experiment was carried out thanks to a specially arranged detection system around zero degrees at the Heavy Ion Research Facility in Lanzhou, Radioactive Ion Beam Line in Lanzhou (HIRFL–RIBLL).

Hamamatsu R1924A is one of the most widely used photomultiplier tubes (PMTs) in nuclear physics. Since the active base suitable for R1924A is still not available in market, an active base is designed for Hamamatsu R1924A PMT, and the test results at high counting rates are presented. The active bases with two different sets of resistor chains were tested and compared by a frequency-controlled green straw hat LED light. A stable signal output up to 100 kHz is achieved using frequency-controlled LED pulsed light. The temperature of bases, which reflects the power consumption and is crucial for applications in vacuum, is also monitored with the same LED pulsed light. The temperature of the active base with smaller resistances reaches about twice of that of the active base with larger resistances in the resistor chain. For the applications in vacuum, the active base with resistance between the two sets of resistor chains may be preferable.

A detector setup for the measurement of angular distribution of heavy-ion elastic scattering at energies around Coulomb barrier on the radioactive ion beam line in Lanzhou at the heavy-ion research facility in Lanzhou is designed. The beam profile and the scattering angles on the target are deduced by two parallel plate avalanche counters, and four sets of detector telescopes (including double-sided silicon strip detectors) are placed systematically with the beam line, incorporating with Monte Carlo simulations. The data of $$^{16}\hbox {O}$$ on $$^{89}\hbox {Y}$$ target were analyzed to compare with the simulation results. It is found that the simulated distribution is agreeable with the experimental data. By assuming the pure Rutherford scattering at small scattering angles, the angular distribution of elastic scattering of $${}^{16}\hbox {O} + {}^{89}\hbox {Y}$$ at low energies can be reasonably obtained. It indicates that this set of detector setup can be used for the measurement of angular distributions of heavy-ion elastic scattering at energies around Coulomb barrier.

The de-excitation of alpha-conjugate nuclei produced in reactions of 35 MeV/nucleon 40Ca with 40Ca has been investigated. Particular emphasis is placed on examining the dynamics of collisions leading to projectile-like fragment exit channels. A general exploration of the reaction systematics reveals the binary dissipative character of the collisions and a hierarchy effect similar to that seen for heavier systems. Investigation of the subset of events characterized by a total alpha-conjugate mass (alpha particles plus alpha-conjugate fragments) equal to 40 and atomic number equal to 20 reveals a dominance of alpha-conjugate exit channels. The hierarchy effect for these channels leads to the production of alpha-clustered neck structures with potentially exotic geometries and properties.

Kawasaki disease (KD) is a kind of pediatric vasculitis of unknown etiology which mainly affects the development of coronary artery aneurysms. Few studies have explored the potential environmental risk factors on KD incidence. We performed a time-series analysis to investigate the associations between air pollution and temperature and KD in Shanghai, China. We collected daily-hospitalized KD patients that were admitted in major pediatric specialty hospitals located in the urban areas of Shanghai from 2001 to 2010. The over-dispersed generalized additive model was used to estimate the effects of air pollutants on KD incidence on each day. Then, this model was combined with a distributed lag non-linear model to estimate the cumulative effects of temperature over a week. There were positive but statistically insignificant associations between three major air pollutants and KD incidence. The association between daily mean temperature and KD was generally J-shaped with higher risks on hot days. The cumulative relative risk of KD at extreme hot temperature (99th percentile, 32.4 °C) over a week was 1.91 [95% confidence interval (CI): 1.13, 3.23], compared with the referent temperature (10.0 °C). This study suggested that a short-term exposure to high temperature may significantly increase the incidence of KD, and the evidence linking air pollution and KD incidence was limited.

The drift of the isospin degree of freedom (IDOF) is experimentally visualized through the wide-range angular distribution and the beam energy dependence of the isospin composition of light charged particles (LCP) produced in heavy ion collisions. It is evidenced that the net isospin transport is presented in the whole process from early dynamic emission to the statistical evaporation lasting to very late stage. Due to the long-time accumulation of the isospin effect, the angular distribution of the relative neutron excess summing over the LCPs is utilized as a sensitive probe to the symmetry energy. With S fixed at 28.3 MeV, a soft density dependence with L=33–61 MeV (0.95 confidential level) at ρ0 is circumstantially deduced using an improved quantum molecular dynamics transport model attached with a statistical emission afterburner.

Ratios of differential chemical potential values relative to the temperature, $({\ensuremath{\mu}}_{n}\ensuremath{-}{\ensuremath{\mu}}_{p})/T$, extracted from isotope yields of 13 reaction systems at 40 MeV/nucleon are compared to those of a quantum statistical model to determine the temperature and symmetry energy values of the fragmenting system. The experimental $({\ensuremath{\mu}}_{n}\ensuremath{-}{\ensuremath{\mu}}_{p})/T$ values are extracted based on the modified Fisher model. Using the density value of $\ensuremath{\rho}/{\ensuremath{\rho}}_{0}=0.56$ from the previous analysis, the temperature and symmetry energy values of $T=4.6\ifmmode\pm\else\textpm\fi{}0.4$ MeV and ${a}_{\mathrm{sym}}=23.6\ifmmode\pm\else\textpm\fi{}2.1$ MeV are extracted in a framework of a quantum statistical model. These values agree well with those of the previous work, in which a self-consistent method was utilized with antisymmetrized molecular dynamics simulations. The extracted temperature and symmetry energies are discussed together with other experimental values published in literature.