[en] This paper reports a 3-d numerical simulation system to analyze the complicated flow in plasma reactors for coal gasification, which involve complex chemical reaction, two-phase flow and plasma effect. On the basis of analytic results, the distribution of the density, temperature and components' concentration are obtained and a different plasma reactor configuration is proposed to optimize the flow parameters. The numerical simulation results show an improved conversion ratio of the coal gasification. Different kinds of chemical reaction models are used to simulate the complex flow inside the reactor. It can be concluded that the numerical simulation system can be very useful for the design and optimization of the plasma reactor

[en] A novel spectrum-fingerprint anti-counterfeiting fiber was developed by using Sr₂ZnSi₂O₇:Eu²⁺,Dy³⁺ and polyacrylonitrile (PAN) as main raw materials by wet spinning. The microstructure, phase structure and spectral properties of the fiber were studied by SEM, XRD and Fluorescence spectrophotometer. The results show that the Sr₂ZnSi₂O₇:Eu²⁺,Dy³⁺/PAN spectrum-fingerprint anti-counterfeiting fiber has similar luminescence characteristics to those of Sr₂ZnSi₂O₇:Eu²⁺,Dy³⁺, the excitation wavelength of which is near 360 nm and the strongest emission peak is 470 nm. Although the addition amounts of luminescent material had no effect on the luminous wavelength of the fiber obviously, it had a great influence on the luminescence intensity of the fiber. Sr₂ZnSi₂O₇:Eu²⁺,Dy³⁺/PAN composite fiber keeps the basic characteristics of spectrum-fingerprint anti-counterfeiting fiber and is a new potential anti-counterfeiting fiber with higher anti-counterfeiting force. (paper)

[en] The mortar loses strength under acid rain conditions, causing cracking, weight loss and damage to the structure. This paper studies the effects of graphenene nanoplatelets(GNP) mortar under simulated acid rain conditions. A control sample without GNP and the addition of GNP were ranging from 0.2% to 0.6% by weight of ordinary Portland cement were prepared. In different corrosion days, the mechanical properties of the GNP cement mortar were measured, scanning electron microscopy also applied. Results showed that the mechanical properties of cement mortar added with graphene are improved. Compared with the control sample, the compressive strength and flexural strength of specimens containing 0.2wt% GNP are increased by 10% and 8%, respectively. Adding GNP can improve the acid resistance and durability of cement mortar. (paper)

[en] Bi₂Sr_2-xLa_xCu₁O_6+δ (La-2201) thin films were successfully prepared on (100) SrTiO₃ and (100) LaAlO₃ substrates by in-situ dc-magnetron sputtering process. A series compensated 2201 targets of La³⁺ substitution contents for Sr²⁺ were studied for growing 2201 phase thin films. The superconducting zero resistance temperature T_c,0 reached 19 K. x-ray diffraction analyses showed that films oriented with c-axis perpendicular to the substrate surface and their lattice parameters are around 2.43-2.46 nm. φ-scan and rocking curve show a good epitaxial growth and crystallisation of the films

[en] In order to find out the light color mixing mechanism of rare earth luminescent materials used in anti-counterfeiting fibers, we prepared three kinds of rare earth luminescent materials according to RGB tri-primary color, and mixed it together to form different mixtures in certain proportion. The phase structures of the luminescent material monomers were measured by x-ray diffractometer. The photochromic properties of the luminescent materials were tested and analyzed by fluorescence spectrophotometer. The results show that the light color mixing was consistent with the blending principle of additive color, but not the same because of the photochromic properties of rare earth luminescent materials, and we explored the reasons in the light wavelength and intensity. It was found that the enhancement of the luminescence intensity of the mixture on account of the superimposing of luminescence. (paper)

[en] FLASH radiotherapy, as a technology of radiation therapy, is mainly characterized by ultra-high dose rate radiation. Due to the unique characteristic, it has become a hot spot in the field of radiotherapy. This paper summarized the findings of previous studies, including the challenges of clinical applications, the technical complexity, and the possible biological mechanisms underlying FLASH radiotherapy, which are important for clinical decisions. (authors)

[en] Highlights: • A shape-memory piezoelectric nanogenerator (sm-PENG) integrated with fixation splint was proposed with good flexibility. • The sm-PENG is fabricated by thermo forming technology. This novel structure can better meet the requirement of therapy. • The effect of self-powered pulsed direct current stimulation can enhance osteogenesis was studied for the first time. Promoting the differentiation of osteoblasts is critical to maintain bone homeostasis for treatment osteoporosis and fracture healing. For these orthopedic diseases, a portable, highly patient compliance therapy device remains a great challenge. Here, we proposed a biomechanical-energy-driven shape memory piezoelectric nanogenerator (sm-PENG) that integrated with fixation splint to promote osteogenic differentiation. The pulsed direct current (DC) generated from the sm-PENG effectively promote MC3T3-E1 preosteoblast cell proliferation, orientation and increase intracellular calcium ion. At the same time, the ALP activity of cells is also improved by pulsed-DC under long-term culture conditions. Ultimately, increasing calcium deposition, extracellular matrix mineralization and osteogenesis. Our work demonstrates the potential of sm-PENG as a power source for pulsed-DC stimulation of bone repair, and shows great prospect self-powered and portable electronic medical device.