摘要：An industrial scale propylene production via oxidative dehydrogenation of propane （ODHP） in multi-tubular re- actors was modeled. Multi-tubular fixed-bed reactor used for ODHP process, employing 10000 of small diameter tubes immersed in a shell through a proper coolant flows. Herein, a theory-based pseudo-homogeneous model to describe the operation of a fixed bed reactor for the ODHP to correspondence olefln over V2O5/γ-Al203 catalyst was presented. Steady state one dimensional model has been developed to identify the operation parameters and to describe the propane and oxygen conversions, gas process and coolant temperatures, as well as other pa- rameters affecting the reactor performance such as pressure. Furthermore, the applied model showed that a double-bed multitubular reactor with intermediate air injection scheme was superior to a single-bed design due to the increasing of propylene selectivity while operating under lower oxygen partial pressures resulting in propane conversion of about 37.3%. The optimized length of the reactor needed to reach 100% conversion of the oxygen was theoretically determined. For the single-bed reactor the optimized length of 11.96 m including 0.5 m of inert section at the entrance region and for the double-bed reactor design the optimized lengths of 5.72 m for the first and 7.32 m for the second reactor were calculated. Ultimately, the use of a distributed oxygen feed with limited number of injection points indicated a significant improvement on the reactor performance in terms of propane conversion and propylene selectivity. Besides, this concept could overcome the reactor run- away temperature problem and enabled operations at the wider range of conditions to obtain enhanced propyl- ene production in an industrial scale reactor.

摘要：Wounds heal through a complex process including four *** interruption or interference in healing process can prevent wound *** is one of the most common complications preventing wounds from *** this study,we investigated the fibroblast cell morphology and behavior of a gelatin-based hydrogel containing anthocyanin to determine whether it can be used for early detection of *** experimental results ascertained that 6 h after culturing the fibroblasts,they could be well attached to the surface of the hydrogel,and 48 h after seeding,they were spread over the surface and connected with each *** the addition of a low dose of anthocyanin,the vitality of the cell increased,and the results of the ATR-FTIR analysis showed that anthocyanin could eliminate remaining glutaraldehyde free *** also could change its color after the addition of bacterial ***,hydrogels containing black carrot anthocyanin may be a potential therapeutic and diagnostic strategy to promote wound healing and early detection of infection.

摘要：Core discing often occurs in deep rocks under high-stress conditions and has been identified as an important characteristic for deep rock *** paper presents the formation mechanism of core discing ***,the interaction between diamond drill bits and rock was analyzed based on numerical modeling.A novel drill bit with an inner conical crown for the mitigation of core discing was designed and verified by simulation *** mitigation method was applied in the cavern B1 of CJPL-Ⅱand satisfactory results had been *** percentage of core discing had been obviously decreased from 67.8%when drilling with a rectangular crown drill bit,to 26.5%when an inner conical crown drill bit had been *** paper gives full insight into core discing characteristics and provides a new method for core discing mitigation;it will potentially contribute to stress measurement in deep rock engineering.

摘要：The spiral has been studied for the first time in the book “About the spirals”, by Archimedes （Greece, 287-212 BC）. In America, the design of spirals seems to have been used previous to Archimedes＇ time, although in the Northwest of Argentina the appearance of this figure in ceramics can be dated between the years 800 and 1,400 （AD）. The spiral is found in cave paintings, in pumpkin carvings and in pottery, particularly those painted inside of plates （pucos in Quechua language）.There can be seen simple linear spirals, double spirals and spirals filled with squares, spirals in two, facing each other symmetrically, as well as spirals joined to bodies of animals. The number of spires detected in the largest spiral is 12, a number of evidently sacred characteristics. When there are several spirals in an earthenware vessel, it can be seen that all of them spin to the same side whether it is clockwise or not. This could have been caused by the predominance of the use of either one hand or the other by the ancient artist. This paper is produced with computer methods used to design spirals in the computer, either Archimedes or the logarithmic ones. Finally, the book： “Man and his symbols” of the psychiatrist Carl Gustav Jung （1875-1961） help to understand this congruencies. In this paper, Mathematics is complemented with the Archeology of art and Psychology.

摘要：This article delivers a robust overview of potential electrode materials for use in symmetrical solid oxide fuel cells(S-SOFCs),a relatively new SOFC *** this end,this article provides a comprehensive review of recent advances and progress in electrode materials for S-SOFC,discussing both the selection of materials and the challenges that come with making that *** article discussed the relevant factors involved in developing electrodes with nano/***,e.g.,non-cobalt and lithiated materials,are only a few of the electrode types now being ***,the phase structure and microstructure of the produced materials are heavily influenced by the synthesis *** into the possibilities and difficulties of the material are *** achieve the desired microstructural features,this article focuses on a synthesis technique that is either the most recent or a better iteration of an existing *** portion of this analysis that addresses the risks associated with manufacturing and the challenges posed by materials when fabricating S-SOFCs is the most *** article also provides important and useful recommendations for the strategic design of electrode materials researchers.

摘要：Role based access control is one of the widely used access control *** are investigations in the literature that use knowledge representation mechanisms such as formal concept analysis(FCA),description logics,and Ontology for representing access control ***,while using FCA,investigations reported in the literature so far work on the logic that transforms the three dimensional access control matrix into dyadic formal *** transformation is mainly to derive the formal concepts,lattice structure and implications to represent role hierarchy and constraints of *** this work,we propose a methodology that models RBAC using triadic FCA without transforming the triadic access control matrix into dyadic formal *** discussion is on two lines of *** present how triadic FCA can provide a suitable representation of RBAC policy and we demonstrate how this representation follows role hierarchy and constraints of RBAC on sample healthcare network available in the literature.

摘要：A computer program was developed in C++language to predict the effect of soil bulk density on draft force on bottoms,share thickness,stresses distribution and maximum deflection on standards,bending stresses distribution on side plates,diameter of shear pins,and tensile stress on hitch *** was found that,as soil bulk density increased,stresses distribution and maximum deflection on standards,bending stresses distribution on side plates,diameter of shear pins,and tensile stress on hitch bar *** diameter of shear pin should be larger to meet wide range of soil density.

摘要：Beams,plates,and shells,as the fundamental mechanical structures,are widely used in microelectromechanical systems(MEMS)and nanoelectromechanical systems(NEMS)as sensors,actuators,energy harvesters,and among *** understand the electromechanical coupling of these dielectric structures is of crucial for designing,fabricating,and optimizing practice devices in these *** we demonstrate the electromechanical coupling in flexoelectric circular plate,in which higher-order strain gradients were considered to extend the classical electromechanical properties to isotropic materials,in which the non-uniform distribution of the electric potential along the radial direction was *** solutions for the vibration modes of the flexoelectric circular plates showed that the dynamic modes were totally different from the piezoelectric circular plates owing to the inversion symmetry breaking by the strain *** electromechanical coupling dynamic modes are sensitive to bending,twisting modes owing to the sensitivity of the flexoelectric effect to *** work provides a fundamental understanding of the electromechanical coupling in flexoelectric circular plate,which is helpful in designing novel flexoelectric circular plate-based devices,such as flexoelectric mirrors.

摘要：The quest for low‐cost yet efficient non‐Pt electrocatalysts for the oxygen reduction reaction(ORR)has become one of the main focuses of research in the field of catalysis,which has implications for the development of the next generation of greener fuel ***,we comprehensively describe the'big picture'of recent advances made in the rational design of ORR electrocatalysts,including molecule‐based,metal‐oxide‐based,metal‐nanomaterial‐based and two‐dimensional *** metals can fabricate molecular electrocatalysts with N4‐macrocycles such as porphyrin‐class compounds and the so‐formed M-N-C active centre plays a crucial role in determining the catalytic performances towards the ***‐IV and‐V Transition metal oxides represent another class of promising alternative of Pt‐based catalysts for the ORR which catalytic activity largely depends on the surface structure and the introduction of surface *** advances in synthesis of metallic nanoparticles(NPs)allow for precise control over particle sizes and shapes and the crystalline facets exposed to enhance the ORR performance of ***‐dimensional materials such as functionalized grapheme or MoS2are emerging as novel electrocatalysts for the *** review covers various aspects towards the design of future ORR electrocatalysts,including the catalytic performance,stability,durability and *** novel electrocatalysts even surpass commercial Pt/C systems,demonstrating their potential to be alternatives in industrial *** the encouraging progress,challenges,which are also described,remain to be overcome before the real‐world application of novel ORR electrocatalysts.

摘要：Introduction 3D bioprinting offers a unique biofabrication platform that allows the generation of functional tissue constructs in a spatially/geometrically controlled and automated manner using a 3 D printer and *** serves as the carrier medium that provides the ideal physico-mechanical characteristics for printability,shape fidelity,and support;and a biological microenvironment for the living cells prior to,during.