摘要：Piezoelectric ceramic based high-temperature acoustic emission(AE)sensor is required urgently in the structural health monitoring of high-temperature *** this research,a series of 0.45(BiSc_(x)O_(3)-BiFe_(1-x)O_(3))-0.48PbTiO_(3)-0.07BaTiO_(3)(BSc_(x)Fe_(1-x)-PT-BT,n(Sc)/n(Fe)=0.4/0.6-0.6/0.4)ceramics with both high Curie temperature and large piezoelectric constant were *** structure and electrical properties of BSc_(x)Fe_(1-x)-PT-BT ceramics as a function of n(Sc)/n(Fe)have been systematically *** the ceramics possess a perovskite structure,and the phase approaches from the rhombohedral toward the tetragonal phase with the decrease of n(Sc)/n(Fe).The BSc_(0.5)Fe_(0.5)-PT-BT and BSc_(0.5)Fe_(0.5)-PT-BT piezoelectric ceramics exhibit good piezoelectricity(d_(33)=250-281 pC/N),high Curie temperature(T_(C)=430-450℃)and excellent temperature *** improvements are greatly attributed to the balance between rhombohedral and tetragonal phase near morphotropic phase boundary with dense microstructure of *** sensor based BSc_(0.5)Fe_(0.5)-PT-BT piezoelectric ceramic was designed,prepared and *** high-temperature stability of AE sensor was characterized through pencil-lead breaking with in situ high-temperature *** noise of AE sensor is less than 40 dB,and the acoustic signal is up to 90 dB at 200℃.As a result,AE sensors based on BSc_(x)Fe_(1-x)-PT-BT piezoelectric ceramics are expected to be applied into the structural health monitoring of high temperature fields.

摘要：The aramid fiber-reinforced composites(AFRC)can increase the durability of corresponding applications such as aerospace,automobile and other large structural parts,due to the improvement in hardness,heat build-up,wear properties and green environmental ***,because of its complex multiphase structure and unique heterogeneity and anisotropy,the poor compression fatigue resistance and the incident surface fibrillation are *** improve the assembly precision of AFRC,mechanical processing is necessary to meet the dimensional *** paper focuses on the influence of contour milling parameters on delamination defects during milling of AFRC laminates.A series of milling experiments are conducted and two different kinds of delamination defects including tearing delamination and uncut-off delamination are investigated.A computing method and model based on brittle fracture for the two different types of delamination are *** results can be used for explaining the mechanism and regularity of delamination *** control strategy of delamination defects and evaluation method of finished surface integrity are further *** results are meaningful to optimize cutting parameters,and provide a clear understanding of surface defects control.

摘要：Heterogeneous molecular catalysts,such as metal phthalocyanines,are efficient electrocatalysts for CO_(2) reduction reaction(CO_(2)RR).However,the rational design and synthesis of a molecular catalyst-based heterostructure for CO_(2)RR remains ***,we developed a crystalline bimetallic phthalocyanine heterostructure electrocatalyst(CoPc/FePc HS),which achieved an excellent CO_(2)-to-CO conversion efficiency(99%)and outstanding long-term stability after 10 h of *** functional theory calculations revealed that the enhancement of CO_(2)RR performance could be attributed to the distinct electron transfer pattern between FePc and *** heterostructural engineering in molecular catalysts would inspire a unique approach for improving CO_(2)RR performance.

摘要：This paper presents a series of first- and second-generation click-modified coumarin-based fluorescent probes for thiols. These molecules demonstrate high turn-on fluorescent response and good selectivity towards aromatic thiols over other relevant reac- tive sulfur species, reactive oxygen species and common nucleophiles. Moreover, probe la can detect thiols in the reduced rabbit plasma sample. Therefore, this approach provides a particularly impressive tool for detecting thiol in biological systems.

摘要：根据沿着重复轴的一种新动态 linearization 技术，双阶段的最佳的反复的学习控制为非线性、非仿射的分离时间的系统被介绍。双阶段显示二个最佳的学习阶段分别地被设计反复地改进控制输入顺序和学习获得。主要特征是控制器设计和集中分析仅仅取决于动态系统的 I/O 数据。换句话说，没有知道系统的任何另外的知识，我们能容易选择控制参数。模拟学习沿着重复轴说明介绍方法的几何集中，在哪个马路的一个例子控制为它的内在的工程重要性是引人注目的交通反复的学习。

摘要：During molten salt cleaning of remanufactured 27SiMn hydraulic support column,oxidation occurs on the surface of metal *** results in a change of the surface roughness of metal substrate after cleaning,which affects subsequent remanufacturing *** decrease the effect is very *** paper analyzed the oxidation mechanism of molten salt cleaning,explored the oxidation reaction that occurred during cleaning,and determined the key process parameters of cleaning that affecting oxidation *** using central composite experimental design method and taking surface roughness variation of 27SiMn steel samples before and after molten salt cleaning as response variable to optimize the key process parameters,the optimal parameters of molten salt for cleaning remanufactured 27SiMn hydraulic support column could be *** results show that the oxidation reaction of cleaning paint dirt can protect metal substrate from oxidation to a certain extent,and cleaning temperature and placement depth of metal substrate have a direct impact on the degree of oxidation *** the cleaning temperature is 300℃and the distance between paint dirt and free surface of molten salt is 0.5 times the height of the parts,the surface roughness variation is ***,the cleaning quality will be improved under such parameters.

摘要：This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eigenfunction expansions. A complex dispersion relation is adopted to describe the wave elevation and energy dissipation over submerged porous bars. In the analytical solution, no limitations on the bar number, bar size, and spacing between adjacent bars are set. The convergence of the analytical solution is satisfactory, and the correctness of the analytical solution is confirmed by an independently developed multi-domain BEM （boundary element method） solution. Numerical examples are presented to examine the reflection and transmission coefficients of porous bars, CR and Cv, respectively, for engineering applications. The calculation results show that when the sum of widths for all the porous bars is fixed, increasing the bar number can significantly improve the sheltering function of the bars. Increasing the bar height can cause more wave energy dissipation and lower CR and Cr. The spacing between adjacent bars and the spacing between the last bar and the vertical wall are the key parameters affecting CR and Ct. The proposed analytical method may be used to analyze the hydrodynamic performance of submerged porous bars in preliminary engineering designs.

摘要：There are various differences and contraries, sometimes, even a vehement collision between religion and science. However, to the understanding of objective things, the cognition principles which the two follow are almost unanimous. Basically, mature religions have established complete theology systems, which are one of the means of human cognition, considering objective reality as cognitive basis, following cognitive universal rules and full of rationality and Irrationality through the cognitive process as well as science.

摘要：在电催化CO_(2)还原(CO_(2)RR)过程中,催化剂的重构经常发生.虽然合理的界面结构与催化位点调控有利于构建优异的电催化剂,但是仍面临诸多挑战.本文通过电化学还原和原位锚定策略合成了单原子铋与铟基底协同的原子桥接结构,从而提高CO_(2)RR的电催化性能.原位结构分析和理论研究表明,多孔碳载体上负载的Bi-In协同位点能够打破原有的结构对称,通过σ键和π*负反馈键形成的电荷密度梯度有利于甲酸盐中间体的吸附,从而实现了高达95.1%的甲酸选择性和持续电解9 d的稳定催化.在太阳能电池驱动下,将5-羟甲基糠醛氧化与CO_(2)RR相耦合,实现了阴极生产甲酸和阳极产生2,5-呋喃二羧酸(88.2%)的高效太阳能-燃料转换选择性.该工作对原子桥连结构活性位点的电催化本质与协同作用机制的理解,为合理设计高性能CO_(2)RR电催化剂提供了重要思路.

摘要：With the gradual depletion of available ore at shallow depth,deep mines have been widely operated around the world and therefore need a longer distance to transport the backfill to the underground *** this case,the determination of pressure drop is more important in the pipeline transportation system *** the pilot loop systems require a large amount of capital and manual investment,even its results are reliable,there is an urgent need to find an alternative simple and cost-saving method to determine the pressure ***,laboratory L-pipe and a pilot-loop tests were employed to study the flow properties of cemented paste backfill cured at various solid and binder *** results indicate that the L-pipe test presented a similar trend to the loop test,but the L-pipe was characterized by higher pressure drop values for various solid and cement *** cement content increased beyond 0%,the paste in the L-pipe showed a slighter difference in pressure drop evolution compared to the paste in the *** results suggest that the simple L-pipe is a workable substitute for semi-industrial loop tests and can provide guidance for designing practical CPB pipeline systems in deep mines.