摘要：A simplified method was proposed for the design of concrete lining in underground rock cavern/tunnel against shock loading. The loading may result from the detonation of explosives on ground surface or ground penetration projectiles exploding adjacent to the cavern/tunnel. The resulting problem necessitates the solution of the dynamics of a beam loaded by a transient pressure uniformly distributed over the span. According to mechanical characteristics of the system with rock bolt and shotcrete, a dynamic support design method based on equivalent single degree of freedom （SDOF） was put forward. The SDOF method was applied to obtaining the maximum displacement at the mid-span of the beam, which is often the controlling factor in the blast-resistant design. In the formulation of the problem, the proposed method combines the phenomena of spalling and structural dynamics theory. An example is provided to demonstrate the applicability of this simplified method.

摘要：The electrochemical oxidation behavior of pyrite in bioleaching system of Acidthiobacillusferrooxidans was investigated by cyclic voltammetry （CV）, polarization curve and electrochemical impedance spectroscopy （EIS）. The results show that in the presence or absence of A. ferrooxidans, the oxidation reaction of pyrite is divided into two steps： the first reaction step involves the oxidation of pyrite to S, and the second reaction step is the oxidation of S to SO4^2-. The oxidation mechanism of pyrite is not changed in the presence of A. ferrooxidans, but the oxidation rate of pyrite is accelerated. With the extension of reaction time of A. ferrooxidan with pyrite, the polarization current density of pyrite increases and the breakdown potential at which the passive film dissolves decreases. The impedance in the presence ofA. ferrooxidans is obviously lower than that in the absence of A. ferrooxidans, further indicating that microorganism accelerates the corrosion process of pyrite.

摘要：The NiS/CQDs nanocomposite (CQDs represents carbon quantum dots), with a mass ratio of NiS/CQDs to be 1.19:1 based on the ICP result, was obtained via a facile hydrothermal method from a mixture of CQDs, Ni(OAc)2 and Na2S. The self-assembly of ZnIn2S4 microspheres on the surface of NiS/CQDs was realized under microwave conditions to obtain a ternary NiS/CQDs/ZnIn2S4 nanocomposite. The as-obtained NiS/CQDs/ZnIn2S4 nanocomposite was fully characterized, and its photocatalytic hydrogen evolution under visible light irradiation was investigated. The ternary NiS/CQDs/ZnIn2S4 nanocomposite showed superior photocatalytic activity for hydrogen evolution than ternary CQDs/NiS/ZnIn2S4, which was obtained by deposition of NiS in the preformed CQDs/ZnIn2S4. The superior photocatalytic performance of ternary NiS/CQDs/ZnIn2S4 is ascribed to the introduction of CQDs, which act as a bridge to promote the vectorial transfer of photo-generated electrons from ZnIn2S4 to NiS. This result suggests that the rational design and fabrication of ternary CQDs-based systems are important for the efficient photocatalytic hydrogen evolution. This study provides a strategy for developing highly efficient noble-metal-free photocatalysts for hydrogen evolution using CQDs as a bridge to promote the charge transfer in the nanocomposite.

摘要：The layout of the buckets for tunnel boring machine(TBM)directly affects the muck removal efficiency of cutterhead during *** order to improve the muck removal performance for TBM,the optimal design of bucket layout was *** whole muck transfer process was simulated by discrete-element method(DEM),including the muck falling,colliding,pilling up,shoveling and transferring into the *** muck model was established based on size distribution analysis of muck samples from the water-supply tunnel project in Jilin Province,***,the influence of the bucket number and the interval angle between buckets on muck removal performance was *** results indicated that,as the number of buckets increased from four to eight,the removed muck increased by 29%and the residual volume decreased by 40.5%,and the process became *** interval angles between buckets were corresponding to different removed muck irregularly,but the residual muck number increased generally with the *** optimal layout of buckets for the cutterhead in this tunnel project was obtained based on the simulation results,and the muck removal performance of the TBM was verified by the actual data in the engineering construction.

摘要：The design of metallic materials with high strength,high ductility,and high thermal stability has always been a long-sought goal for the materials science ***,the trade-off between strength and ductility remains a ***,we proposed a new strategy to design and fabricate bulk amorphous-crystalline dual-phase superior alloys out of the Al_(80)Li_(5)Mg_(5)Zn_(5)Cu_(5)multicomponent *** nano-amorphous phase revealed unexpected thermal stability during fabrication and mechanical testing above the crystallization *** true fracture strength of the Al_(80)Li_(5)Mg_(5)Zn_(5)Cu_(5)nano-amorphous-crystal dual-phase multicomponent alloy was increased from 528 to 657 MPa,and the true strain was increased from 18%to 48%.In addition,the alloy yielded a strength 1.5 times higher than that of the commonly used high-strength aluminum alloys at 250℃.This strategy provided a new approach and concept for the design of high-performance alloys to ensure strength-plasticity balance.

摘要：Collision and security issues are considered as barriers to RFID *** this paper,a parallelizable anti-collision based on chaotic sequence combined dynamic frame slotted aloha to build a high-efficiency RFID system is *** the tags parallelizable identification,we design a Discrete Markov process to analyze the success identification *** a mutual authentication security protocol merging chaotic anti-collision is *** theoretical analysis and simulation results show that the proposed identification scheme has less than 45.1%of the identification time slots compared with the OVSF-system when the length of the chaos sequence is *** success identification rate of the proposed chaotic anti-collision can achieve 63%when the number of the tag *** test the energy consumption of the presented authentication protocol,which can simultaneously solve the anti-collision and security of the UHF RFID system.

摘要：In this paper, we present a novel design scheme of temperature-jump(T-jump) area for microfluidic *** simulation and experimental research of thermal characteristics of the solution in microchannels is *** simulation of the temperature-jump microchannel is analyzed to study the heat transfer characteristics by comparing performance of three proposed *** of the power requirement is discussed in the dimensional design of microheater. Temperature-sensitive fluorescent dye is applied to investigate the temperature field of microchannel heated by a designed microheater. It is found that the T-jump microfluidic device can provide rapid heating for solutions with strong convection heat transfer ability.

摘要：Acidic oligosaccharide sugar chain （AOSC）, a D-mannuronic acid oligosaccharide, derived from brownalgaepolysaccharide, has been completed Phase I clinical trial in china as an anti-Alzheimer＇s Disease （AD） drug candidate. The identification of AOSC-binding protein（s） in neurons is very important for understanding its action mechanism. To determine the binding protein（s） of AOSC in neurons mediating its anti-AD activities, confocal microscopy, affinity chromatography, and liquid chromatography-tandem mass spectrometry （LC-MS/MS） analysis were used. Confocal microscopy analysis shows that AOSC binds to SH-SY5Y cells in concentration-, time-, and temperature-dependent fashions. The AOSC binding proteins were purified by affinity chromatography and identified by LC-MS/MS analysis. The results showed that there are 349 proteins binding AOSC, including clathrin, adaptor protein-2 （AP-2） and amyloid precursor protein （APP）. These results suggest that the binding/entrance of AOSC to neurons is probably responsible for anti-AD activities.

摘要：In this paper,we propose a homogenization theory for designing graded viscoelastic sonic crystals（VSCs） which consist of periodic arrays of elastic scatterers embedded in a viscoelastic host *** extend an elastic homogenization theory to VSC by using the elastic-viscoelastic correspondence principle and propose an analytical effective loss factor of *** results of VSC and the equivalent structure calculated by using the finite element method are in good *** to the relation of the effective loss factor to the filling fraction,a graded VSC plate is easily and quickly ***,the graded VSC may have potential applications in the vibration absorption and noise reduction fields.

摘要：The effect of sodium hexametaphosphate（SHMP） on the separation of serpentine from pyrite and its mechanism were studied systematically through flotation tests,sedimentation tests,surface dissolution,ζ potential tests,adsorption measurements,and infrared spectroscopic *** results show that the SHMP could significantly reduce the adverse effect of serpentine on the flotation of pyrite and make the mixed sample of pyrite and serpentine more disperse in the alkaline condition,thus improve the adsorption of xanthate on *** action mechanism of the SHMP is that it lowers the pH value at the isoelectric point of serpentine and enhances the negative charge through the dissolution of magnesium from the surface of serpentine and adsorbing on the surface of *** changes the total interaction energy between serpentine and pyrite from gravitational potential energy to repulse potential energy,according to the calculation of the EDLVO theory.