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[en] Graphical abstract: A novel material based on the use of magnetic Fe3O4 nanoparticles coated with MMIP for preconcentration and determination of RhB in real samples prior to fluorospectrophotometry was developed. - Highlights: • A novel rhodamine B magnetic molecularly imprinted polymer by using Fe3O4 magnetite as the magnetically susceptible component was synthesized. • The MMIP had rapid adsorption and high selectivity towards rhodamine B. • Rhodamine B can be extracted selectively by MMIP from real samples. • The method provides the advantages of short analysis time and high sensitivity. - Abstract: A novel magnetic molecularly imprinted polymer (MMIP) was developed as an adsorbent to selectively remove rhodamine B from real samples. The polymer was characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermo-gravimetric analysis. Static adsorption, kinetic adsorption, and selective recognition experiments were also performed to investigate the specific adsorption equilibrium, kinetics, and selective recognition ability of the MMIP. The MMIPs had outstanding thermal stability, large adsorption capacity, and high competitive selectivity. When they were used as dispersed solid-phase extraction adsorbents in real samples, rhodamine B recovery was 79.97–81.88% and 75.56–79.74% in intra-day and inter-day reproducibility experiments with relative standard deviations lower than 2.62% and 4.28%, respectively. Extraction was optimized for yield and efficiency. Precision, accuracy, and linear working range were determined under optimal experimental conditions. The limits of detection and quantification were 1.05 and 3.49 μg L−1, respectively. These results suggest MMIPs may be used for determination of rhodamine B in real samples
Journal
[en] Objective: To examine the status quo of radiological protection for radiotherapy units in a certain province, investigate the existing problems and propose the corresponding suggestions. Methods: The sample of law enforcement files of radiotherapy units for a certain province in 2010, acquired by health supervision, was analyzed by statistic software of SPSS 13.0. Results: In 23 radiotherapy units, the rate of holding 'Radiation Treatment Permits' is 91.3%, radiation workers with 'Certificate of Radiation Workers' is 80.5%, occupational health examination is 95.9%, individual dose monitoring is 98.5%, the inspecting rate of radiotherapy equipments is 86.8%, the configuring rate of radiation dose scanners is 43.5%, personal alarm dosimeters is 73.9%, and the number of medical physics staffs is 36. Conclusion: There are still some organizations, workers and large medical equipments haven't obtained permissions. The medical physics staffs and associated equipments are not enough. Hospitals and health administrative departments need to improve the work of radiological protection and administration, especially speeding up the process of granting permits, completing the deposing of equipments and staffs, strengthening the propaganda and training of radiation protection knowledge and regulations, completing radiation protection management system. (authors)
Journal
Chinese Journal of Radiological Health; ISSN 1004-714X; 
; v. 22(5); p. 543-545
; v. 22(5); p. 543-545
[en] We consider a 5-dimensional scalar-tensor theory which is a direct generalization of the original 4-dimensional Brans-Dicke theory to five dimensions. By assuming that there is a hypersurface-orthogonal spacelike Killing vector field in the underlying 5-dimensional spacetime, the theory is reduced to a 4-dimensional theory where the 4-metric is coupled with two scalar fields. The cosmological implication of this reduced theory is then studied in the Robertson-Walker model. It turns out that the two scalar fields may account naturally for the present accelerated expansion of our universe. The observational restriction of the reduced cosmological model is also analyzed
Journal
[en] Using experimental phantom simulating thyroid nodules, investigation was made of the diagnostic value of ultrasound, CT and radionuclide imaging in thyroid nodules. The results showed that the detectability and accuracy of ultrasound, CT and radionuclide imaging were 90.9%, 91.4%, 84.8% and 100%, 92%, 100%, respectively. However, in ultrasound, there was 7.6% false positive. While in the radionuclide imaging, pinhole collimator was better than paralleled collimator for both planar and tomography imaging, especially in small thyroid nodules (< 5 mm). Thereby, it indicated that pinhole tomography do improve the detection of small thyroid nodules
Journal
Nuclear Techniques; ISSN 0253-3219; ; v. 21(11); p. 693-696
; v. 21(11); p. 693-696
[en] Layered double hydroxides (LDHs) are promising Faradaic materials for the construction of high-performance supercapacitors, due to their unique two-dimensional lamellar structures and remarkable stability. Herein, hierarchical porous NiCo LDHs integrated with flexible carbon nanotubes (CNT)/cotton fabric current collector, are realized by a facile method, which exhibits a high capacitance of 811 F g−1 at 0.1 A g−1 in a three-electrode mode. Moreover, the hybrid electrode has been assembled into a flexible supercapacitor device, where the mass capacitance reaches 47.25 F g−1 with a good cycling stability of 94% capacitance retention after 3000 cycles. The better flexibility and conductivity of the CNT, and highly intrinsic electrochemical activity of the NiCo LDHs as well as the superiority of the interwoven structure are responsible for the outstanding performance of the supercapacitor. The elaborate structural design can provide new insights into the construction of high-performance flexible supercapacitors.
Journal
[en] A recent study has found an explosive synchronization in a Kurammoto model on scale-free networks when the natural frequencies of oscillators are equal to their degrees. In this work, we introduce a quantity to characterize the correlation between the structural and the dynamical properties and investigate the impacts of the correlation on the synchronization transition in the Kuramoto model on scale-free networks. We find that the synchronization transition may be either a continuous one or a discontinuous one depending on the correlation and that strong correlation always postpones both the transitions from the incoherent state to a synchronous one and the transition from a synchronous state to the incoherent one. We find that the dependence of the synchronization transition on the correlation is also valid for other types of distributions of natural frequency. (general)
Journal
Communications in Theoretical Physics; ISSN 0253-6102; ; v. 61(2); p. 197-202
; v. 61(2); p. 197-202
[en] In this paper, we investigate the electron transfer (ET) in donor-acceptor model. The Langevin equation with random forces is used. The oscillations of the primary states observed in experimental data have been shown with this approach. And other features on the dependence of the rate of ET on temperature, free energy, and reorganization energy have also been clearly shown. (interdisciplinary physics and related areas of science and technology)
Journal
Communications in Theoretical Physics; ISSN 0253-6102; ; v. 61(5); p. 659-662
; v. 61(5); p. 659-662
[en] This paper reports on a novel method of endowing PET fabric with the properties of moisture absorption, perspiration and thermal conductivity. We firstly synthesized hydrophilic finishing agent with polyethylene glycol 400 (PEG) and isocyanatoethyl methacrylate. Then mercapto-functionalized reduced graphene oxide was dispersed into the hydrophilic finishing agent and applied on mercapto modified PET fabric to form chemical bonding through thiol–ene click chemistry under UV radiation. The process was confirmed by Fourier transforms infrared spectra and scanning electron microscope. Liquid moisture performance on the fabric was evaluated by Moisture Management Tester, and thermal conductivity is characterized by changes in the fabric temperature under a forward-looking infrared. The results revealed that the wetting time, absorption rate, spreading speed and max wetted radius of the treated fabric reached level 4 or above, and one-way transport capability achieved level 3. Besides, the thermal conductivity was obviously improved, indicating this fabric has great potential applications in sportswear fields.
Journal
[en] In this paper, functional polyimide (PI) fabric with high electrically conductive and electromagnetic shielding effect was prepared by nickel-tungsten-phosphorus (Ni-W-P) electroless plating. Firstly, a wave-absorbing and conductive polyaniline (PANI) layer was in-situ polymerized on the surface of fabric. Secondly, the PANI reduced the palladium ions to palladium particles acting as catalytically active sites. Finally, Ni-W-P electroless plating was initiated and formed a uniform and dense layer. The features of Ni-W-P alloy layer on PI fabric were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The thermal stability of the sample was also evaluated by thermogravimetric analysis (TGA). The results showed that the electrical conductivity was 0.08 Ω/sq and the outstanding electromagnetic shielding effectiveness (SE) could reach 103 dB. Moreover, the robust SE performance after multiple ultrasonic washing and bending tests also implied the resultant material had a great potential in the textile protection fields.
Journal
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