摘要：Ce element was introduced to modify Al−2%Fe(mass fraction)binary *** microstructures,crystallization behavior,electrical/thermal conductivities and mechanical properties of these alloys were systematically *** results indicated that the appropriate Ce addition decreased the recalescence temperature and growth temperature of Al−Fe eutectic structure,improved the morphology and distribution of Fe-containing phase,and simultaneously increased the conductivity and mechanical *** annealed treatment improved the thermal conductivity of these alloys due to the decreasing concentration of point *** process further broke up the coarser Fe-containing phases into finer particles and made the secondary phases uniformly distributed in theα(Al)*** subsequent annealing treatment and rolling deformation,the thermal conductivity,ultimate tensile strength and hardness of the Al−2%Fe−0.3%Ce(mass fraction)alloy reached 226 W/(m·K),(182±1.4)MPa and HBW(49.5±1.7),respectively.

摘要：Roof pre-splitting is an effective method to control the roof with potential rock burst *** this study,three-point bending tests were carried out by using fine sandstone specimens with different pre-cracked lengths as test objects,and digital speckle correlation method(DSCM)and acoustic emission(AE)technology were used to track the entire process of crack *** effect of pre-cracks on the fracture of rock beams was evaluated,and the mechanical mechanism of the rock beam fracture process was *** rock beam pre-splitting design method was developed,and the application effect of the method was proved by the microseismic monitoring data obtained from the 10303 working face of Jining No.2 coal mine in *** results show that the loading time history curve of pre-cracked beams exhibits obvious residual *** with the intact rock beam,the tensile strength,and maximum tensile strain of 35 mm pre-cracked rock beam are decreased by 32.4% and 33.1%,respectively and the acoustic emission b value is increased by 30.2%.According to the pre-splitting design method of rock beam,the maximum and average microseismic energy of the 10303 working face after pre-splitting construction are reduced by 25.6% and 6.4%,respectively,with excellent prevention and control effect of thick roof.

摘要：As high-rise cooling towers are constantly emerging,wind effects on this kind of wind-sensitive structures have attracted more and more attention,especially in typhoon prone *** Type B turbulent flow fields under the normal wind and typhoon are simulated by active wind tunnel technology,and rigid-pressure-measurement model and aero-elastic-vibration-measurement model of a large cooling tower are *** stagnation point,peak suction point,separation point and leeward point of the throat position shell are selected to analyze pressure coefficient,probability distribution,peak factor,power spectral density and dynamic amplification factor under normal wind and *** is clarified that there exists a significant non-Gaussian characteristic under typhoon condition,which also exists in structural response *** response ratio of the total response is higher during typhoon *** maximum value of dynamic amplification coefficient under typhoon field is up to 1.18 times over that under normal *** findings of this study are expected to be of interest and practical use to professional and researchers involved in the wind-resistant designs of super-large cooling towers in typhoon prone regions.

摘要：Extremely small-sized iron oxide nanoparticles(ESIONPs)with sizes less than 5 nm have shown great promise as T_(1)contrast agents for magnetic resonance imaging(MRI).However,their facile and scalable production with simultaneously endowed biocompatible surface chemistry remains difficult to be *** this study,by using the coprecipitation method implemented in a specially designed gas/liquid mixed phase fluidic reactor,polyglucose sorbitol carboxymethyether(PSC)coated ESIONPs were continuously synthesized with controllable particle sizes ranging from 1.8 to 4 *** the differently sized ESIONPs,the 3.7-nm ESIONPs exhibit the best performance as T_(1)MRI contrast agent,featuring a high r_(1) value of 4.11(mmol L^(−1))^(−1)s^(−1)and low r_(2)/r_(1) ratio of 7.90 under a clinical 3 T MR scanning,as well as the excellent T_(1)MRI contrast effect in not only water but also the cellular environment and blood ***,the ESIONPs possess long-term stability and good dispersity in aqueous dispersions,making them ideal candidates as safe and effective T_(1)-weighted MRI contrast agent for real clinical use.

摘要：Flexible and wearable sensors have drawn ex-tensive concern due to their wide potential applications inwearable electronics and intelligent robots. Flexible sensorswith high sensRivity, good flexibility, and excellent stabilityare highly desirable for monitoring human biomedical signals,movements and the environment. The active materials and thedevice structures are the keys to achieve high *** nanomaterials, including carbon nanotubes （CNTs）,graphene, carbon black and carbon nanofibers, are one of themost commonly used active materials for the fabrication ofhigh-performance flexible sensors due to their superiorproperties. Especially, CNTs and graphene can be assembledinto various multi-scaled macroscopic structures, includingone dimensional fibers, two dimensional films and three di-mensional architectures, endowing the facile design of flexiblesensors for wide practical applications. In addition, the hybridstructured carbon materials derived from natural bio-mate-rials also showed a bright prospect for applications in flexiblesensors. This review provides a comprehensive presentation offlexible and wearable sensors based on the above variouscarbon materials. Following a brief introduction of flexiblesensors and carbon materials, the fundamentals of typicalflexible sensors, such as strain sensors, pressure sensors,temperature sensors and humidity sensors, are ***, the latest progress of flexible sensors based on carbonmaterials, including the fabrication processes, performanceand applications, are summarized. Finally, the remainingmajor challenges of carbon-based flexible electronics are dis-cussed and the future research directions are proposed.

摘要：Because of their boundary-free and long-rangedisordered microstructure,Fe-based metallic glasses(MGs)exhibit an ultra-low pinning effect on the magnetic domain and unparalleled soft-magnetic properties[1-3],and thus are increasingly used in electric devices for the energy-saving and high-efficiency requirements[4,5].

摘要：Lithium(Li) metal is widely considered as a promising anode for next-generation lithium metal batteries(LMBs) due to its high theoretical capacity and lowest electrochemical potential. However, the uncontrollable formation of Li dendrites has prevented its practical application. Herein, we propose a kind of multifunctional electrolyte additives(potassium perfluorinated sulfonates) from the multi-factor principle for electrolyte additive molecular design(EDMD) view to suppress the Li dendrite growth. The effects of these additives are revealed through experimental results, molecular dynamics simulations and firstprinciples calculations. Firstly, K^(+)can form an electrostatic shield on the surface of Li anode to prevent the growth of Li dendrites. Secondly, potassium perfluorinated sulfonates can improve the activity of electrolytes as co-conductive salts, and lower the electro-potential of Li nucleation. Thirdly, perfluorinated sulfonate anions not only can change the Li^(+)solvation sheath structure to decrease the desolvation energy barrier and increase the ion migration rate, but also can be partly decomposed to form the superior solid electrolyte interphase(SEI). Benefited from the synergistic effects, an outstanding cycle life over250 h at 1 m A cm^(-2) is achieved in symmetric Li||Li cells. In particular, potassium perfluorinated sulfonate additives(e.g., potassium perfluorohexyl sulfonate, denoted as K+PFHS) can also contribute to the formation of high-quality cathode electrolyte interphase(CEI). As a result, Li||LiNi_(0.6)Mn_(0.2)Co_(0.2)O_(2) full cells exhibit significantly enhanced cycling stability. This multi-factor principle for EDMD offers a unique insight on understanding the electrochemical behavior of ion-type electrolyte additives on both the Li metal anode and high-voltage cathode.

摘要：The energy crisis and global warming become severe issues. Solar-driven CO2 reduction provides a promising route to confront the predicaments, which has received much attention. The photoelectrochemical（PEC） process,which can integrate the merits of both photocatalysis and electrocatalysis, boosts splendid talent for CO2 reduction with high efficiency and excellent selectivity. Recent several decades have witnessed the overwhelming development of PEC CO2 reduction. In this review, we attempt to systematically summarize the recent advanced design for PEC CO2 reduction. On account of basic principles and evaluation parameters, we firstly highlight the subtle construction for photocathodes to enhance the efficiency and selectivity of CO2 reduction, which includes the strategies for improving light utilization, supplying catalytic active sites and steering reaction ***, diversiform novel PEC setups are also *** exploited setups endow a bright window to surmount the intrinsic disadvantages of photocathode, showing promising potentials for future applications. Finally, we underline the challenges and key factors for the further development of PEC CO2 reduction that would enable more efficient designs for setups and deepen systematic understanding for mechanisms.

摘要：Pt/Au/WO_3 bimetallic catalysts were prepared by impregnation of Pt onto preformed Au/WO_3,obtained by a hexadecyl trmethyl ammonium bromide（CTAB）-assisted one-pot synthesis *** resulting Pt/Au/WO_3 catalysts exhibited remarkable synergistic effects for selective hydrogenolysis of glycerol to 1,3-propanediol. The characterization results showed that doping of Au promoted the reduction of both Pt and W at low temperatures and uniform dispersion of Pt on the WO_3 support. Furthermore, more low-valence Pt species were produced on the WO_3 surface after introduction of Au. These changes in electronic properties resulted in enhancement of both glycerol conversion and selectivity for 1,3-propanediol.

摘要：An optimized compound 9-(9,9-dimethylacridin-10(9 H)-yl)-6 H-benzo[c]ch-romen-6-one(MAB) was designed and synthesized based on our previously reported TADF emitter 6-(9,9-dimethylacridin-10(9 H)-yl)-3-methyl-1 H-isochromen-1-one(MAC) to further improve the performance of thermally activated delayed fluorescence(TADF)emitters. With the additional phenyl in coumarin-contained plane, MAB possesses an extended distribution of the lowest unoccupied molecular orbitals(LUMO), and thus realizes reduced electron exchange between the frontier molecular orbitals and a stretched molecular dipole moment compared with MAC. MAB based organic light-emitting diode(OLED)exhibits a remarkable maximum external quantum efficiency(EQE) of 21.7%, which is much better than the maximum EQE of MAC-based OLED with a value of 12.8%. Our work proves that extending the distribution of LUMO is a simple but effective method to improve the efficiency of TADF emitter.