摘要：A novel methodology for the formulation design of the multi-component cement additive for the low early strength blend cement was presented by using engineering *** of cement additive such as triethanolamine,chloride,saccharide and a kind of divalent alcohol were simultaneously tested according to the arrangement of response surface *** models were established to express the quantitative relationship between the chemical components of cement additive and the compressive strength of treated blend *** effectiveness and the possible interactions of these four chemicals contributing to the strength development of blend cement were further explored by the pareto chart and the contour *** according the performance analysis of four chemicals,the optimized formulations were brought forward and were validated in practical trials by Turkey＇s multiple comparison.

摘要：To enhance the performance of the polyphenylene sulfone(PPSU) membrane,a novel mixed matrix membrane with hydrophilicity and antifouling properties was *** PPSU as the ba sic membrane material,polyvinyl pyrrolidone(PVP) as the porogen,N-Methyl pyrrolidone(NMP) as the solvent,and MOF-CAU-1(Al_(4)(OH)_(2)(OCH_(3))_4(H_2 N-BDC)_(3)·xH_(2) O) as the filler,PPSU/CAU-1 mixed matrix membrane(MMM) was prepared by an immersion precipitation and phase transformation *** changing the amount of MOF-CAU-1,the properties and performance of the MMM membrane were investigated in terms of hydrophilicity,pore morphology,surface roughness,and dye *** results show that the highest pure water flux of the mixed reached 47.9 L·m^(-2)·h^(-1), when the CAU-1 addition amount was 1.0 wt%, which was 23% higher than that of the pure PPSU *** the rejection rate and the antifouling performance of the MMM membrane also noticeably improved.

摘要：How to control the quality of the coatings has become a major problem during the plasma spraying. Because nozzle contour has a great influence on the characteristic of the plasma jet, two kinds of plasma torches equipped with a standard cylindrical nozzle and a converging-diverging nozzle are designed for low pressure plasma spraying（LPPS） and very low pressure plasma spraying（VLPPS）. Yttria stabilized zirconia（YSZ） coatings are obtained in the reducing pressure environment. The properties of the plasma jet without or with powder injection are analyzed by optical emission spectroscopy, and the electron temperature is calculated based on the ratio of the relative intensity of two Arlspectral lines. The results show that some of the YSZ powder can be vaporized in the low pressure enlarged plasma jet, and the long anode nozzle may improve the characteristics of the plasma jet. The coatings deposited by LPPS are mainly composed of the equiaxed grains and while the unmelted powder particles and large scalar pores appear in the coatings made by VLPPS. The long anode nozzle could improve the melting of the powders and deposition efficiency, and enhance the coatings＇ hardness. At the same time, the long anode nozzle could lead to a decrease in the overspray phenomenon. Through the comparison of the two different size＇s nozzle, the long anode is much more suitable for making the YSZ coatings.

摘要：Electrides are unique ionic compounds that electrons serve as the anions. Many electrides with fascinating physical and chemical properties have been discovered at ambient condition. Under pressure, electrides are also revealed to be ubiquitous crystal morphology, enriching the geometrical topologies and electronic properties of electrides. In this Review,we overview the formation mechanism of high-pressure electrides(HPEs) and outline a scheme for exploring new HPEs from pre-design, CALYPSO assisted structural searches, indicators for electrides, to experimental synthesis. Moreover, the evolution of electronic dimensionality under compression is also discussed to better understand the dimensional distribution of anionic electrons in HPEs.

摘要：Crimping is widely adopted in the production of large-diameter submerged-arc welding pipes. Traditionally, designers obtain the technical parameters for crimping from experience or by trial and error through experiments and the finite element(FE) method. However, it is difficult to achieve ideal crimping quality by these approaches. To resolve this issue, crimping parameter design was investigated by multi-objective optimization. Crimping was simulated using the FE code ABAQUS and the FE model was validated experimentally. A welding pipe made of X80 high-strength pipeline steel was considered as a target object and the optimization problem for its crimping was formulated as a mathematical model and crimping was optimized. A response surface method based on the radial basis function was used to construct a surrogate model; the genetic algorithm NSGA-II was adopted to search for Pareto solutions; grey relational analysis was used to determine the most satisfactory solution from the Pareto solutions. The obtained optimal design of parameters shows good agreement with the initial design and remarkably improves the crimping quality. Thus, the results provide an effective approach for improving crimping quality and reducing design times.

摘要：Electrochemical impedance spectroscopy(EIS) and electrochemical noise(EN) techniques were used to detect stress corrosion cracking(SCC) on 40Cr steel specimens exposed to the acidified chloride solution at ambient. To test these two techniques,slow strain rate tensile(SSRT) tests were performed with 40Cr specimen in the identical corrosive solution at room temperature. In impedance measurements,phase shifts in frequency range from 1 to 1 000 Hz show a clear difference between the stressed and non-stressed specimens,suggesting that stress corrosion cracks are detected by the impedance measurements. EN signals in the process of SCC were recorded and then analyzed by standard deviation(STD). On the other hand,the mechanical properties,such as maximum tensile strength(MTS) and fracture strain(FS) measured by the SSRT,decrease significantly when the specimens are exposed to the corrosive solution relative to that in an inert medium. The SSRT results are consistent with fractography of the tested specimens by scanning electron microscopy(SEM). Analysis of the fracture surface clearly shows intergranular attack,suggesting that stress corrosion cracks are formed.

摘要：In order to give a true reflection of the spatial structure of woven fabric, a circular mathematical model is established based on the Peirce＇s model and the principle of the coordinate transformation. The circular model uses arcs and tangent lines as the yarn flexion shape and selects the circle as the yarn cross-section. Then, a new elliptical cross-section mathematical model is rapidly built by the Jaeobian transformation of the circular model. The Matiab software is used for the 3D simulation. It is shown that 3D simulations of woven fabrics with different weft and warp yarn counts, weft and warp densities, structure phases, weaves and flattening coefficients are successfully realized by Matiab basing on the elliptical mathematical model.

摘要：A new composition of Portland cement clinker was studied, in which KH, SM and IM was 0.98,2.4 and 2.4 respectively as well as its meal added 1%CuO （in mass）. Fired at 1 200℃,1 350℃,1 400℃ and 1 450℃ for 30 min, the resultant mineral phases component and mineral morphology were analyzed. The performances of the cement which was made of clinker burned at 1 450℃ and fly ash were determined. By means of QXRD, XRD and optical microscopy, it is shown that the clinker burnt at 1 450℃ has the larger size crystals and distinct crystal interface, in which the C3S content is 73.37% and the mineral phases is dominantly C3S, following by minor C2S, C3A and tetracalcium aluminoferrite. The results reveal that a new type of high C3S content clinker can completely be made by traditional temperature-time schedule. The performances of the cement produced from this clinker with addtion of 50% fly ash and 5% gupsum were in agreement with the 32.5 strength grade of Portland fly-ash cement. The results also show that the clinker has a significant effect of saving energy and utilizing waste slag.

摘要：Laying head is a high-precision engineering device in hot-rolled high speed wire rod production line. Previously research works are focused on the laying pipe wear-resisting. Laying pipe curve design method based on wire rod kinematics and dynamics analyses are not reported before. In order to design and manufacture the laying pipe, the motion and force process of the wire rod in the laying pipe should be studied. In this paper, a novel approach is proposed to investigate the force modeling for hot-rolled wire rod in laying pipe. An idea of limited element method is used to analysis and calculates the forces between laying pipe inner surface and wire rod. The design requirements of laying pipe curve for manufacturing are discussed. The kinematics and dynamics modeling for numerical calculation are built. A laying pipe curve equation is proposed by discussing design boundary conditions. Numerical results with di erent laying pipe curves design parameters are plotted and compared. The proposed approach performs good result which can be applied for laying pipe curve design and analysis for engineering application.

摘要：At present,metal-organic framework(MOF)-derived nano-micro architectures are actively explored for electromagnetic(EM)wave absorption owing to their flexible composition and structural manipulation that enhance dielectric and magnetic ***,the basic design principles in MOF-derived microwave absorption materials have not been *** review is devoted to analyzing design principles in MOF-derived microwave absorption materials from the following perspectives:diverse monomers(ligands and ions of MOFs),topologies,chemical states,and physical *** derived essential information regarding the EM wave absorption mechanism and the structural-functional dependency is also comprehensively ***,a clear insight into the challenges and perspectives of the industrial revolution upgrading in this promising field is proposed.