Magnetic Flux Controllers for Induction Heating Applications

Application of magnetic flux controllers/concentrators to induction heating coils can drastically improve the process efficiency and heat pattern control. Presentation includes: benefits provided by flux controllers, materials available for controllers, application techniques, computer assisted design of induction coils with concentrators, examples of applications. Depending on induction system design, magnetic flux controllers can concentrate heating in a specified area,change heat source distribution and shield a particular part zone or external area preventing unintended eddy current heating.Besides of the coil efficiency improvement and optimal power distribution, magnetic flux controllers reduce the coil current demand from a supplying circuitry thus strongly reducing losses in busswork, cables, transformers and inverter components.Improvement that can be achieved due to magnetic flux controllers is case dependable. 2D and 3D computer simulation allows the designer to predict accurately effect of controllers on the coil parameters and temperature distribution and optimize the whole electromagnetic system. Special attention in presentation is paid to new magnetodielectric materials optimized for induction heating conditions. These materials have high magnetic permeability and saturation flux density,excellent machinability, good chemical and temperature resistance. Concentrators from these materials can work in a wide range of frequencies and specific powers. Examples of magnetic flux controller application include surface hardening of shafts and gears, induction surface hardfacing and brazing.     

Zeolite based films, membranes and membrane reactors: Progress and prospects

The integration of reaction and separation in catalytic membrane reactors has received increasing attention during the past 30 years. The combination promises to deliver more compact and less capital-intensive processes with substantial savings in energy consumption. With the advent of new inorganic materials and processing techniques, there has been renewed interest in exploiting the benefits of membranes in many industrial applications. Zeolite membranes, however, have only recently been considered for catalytic membrane reactor applications. Despite the significant recent interest in these types of membranes there are relatively few reports of the application of such membranes in high-temperature catalytic membrane reactor applications. This can be attributed to a number of limitations that still need to be addressed such as the relatively high price of membrane units, the difficulty of controlling the membrane thickness, permeance, high-temperature sealing, reproducibility and the dilemma of upscaling. A number of research efforts, with some degree of success have been directed to finding solutions to the remaining challenges. This review makes a critical assessment of what has been achieved in the past few years in terms of hurdles that still stand in the way of the successful implementation of zeolite membrane reactors in industry.     

釉上金红颜料的研制

采用液相反应法研制了釉上金红颜料，给出了颜料和熔剂配方及其制备方法。     

Plasma graft polymerization of acrylamide onto crosslinked HTPB based PU membrane for pervaporation

Pervaporation of water-ethanol mixtures through plasma graft polymerization of acrylamide onto crosslinked hydroxyl terminated poly-butadiene (HTPB) based PU membranes, plasma graft polymerization of acrylamide onto crosslinked PU membrane (AAm-p-CPU), were investigated. The grafting was dependent on the discharge power and pretreatment period. The effects of crosslinking, plasma treatment conditions, feed compositions, and feed temperature on the performance of these membranes were studied. The physical properties of crosslinked membrane were better than those of the uncrosslinked membrane. In addition, compared with crosslinked PU membranes (CPU), the plasma modified crosslinked PU membranes effectively improve the pervaporation separation performances.     

氧泵型催化膜反应器中甲烷氧化偶联反应(Ⅰ)——氧泵型催化膜的制备及其反应性能

本文采用1％Sr/La_2O_3-Ag-YSZ氧泵型催化膜反应器进行了甲烷氧化偶联反应研究。比较了不同制备方法的催化膜的反应性能,结果发现浸涂法(Ag-YSZ管随旋转轴转动涂制)制备的膜性能最佳。研究了操作条件对甲烷氧化偶联反应的影响。研究证明,传递氧与气相氧同时进料是一种较好的反应方式。结果表明,利用该反应器不仅可以简化分离过程,而且还可得到更高的C_2烃选择性。     

ABSORPTION OF CO2 INTO AQUEOUS SOLUTIONS OF STERICALLY HINDERED METHYL AMINOETHANOL USING A HYDROPHOBIC MICROPOROUS HOLLOW FIBER CONTAINED CONTACTOR

The absorption of dilute CO₂ into aqueous solutions of sterically hindered 2-methyl aminoethanol (MAE) and the desorption of CO₂ from CO₂-loaded MAE solutions into N₂ stream were investigated separately for the various combinations of operational variables, using a hydrophobic microporous hollow fiber (polytetrafluoroethylene, PTFE) contained gas-liquid contactor with aqueous solutions of MAE as liquid media in the shell side at 30°C. The absorption of CO₂ in this contactor is governed by resistance in the liquid and hollow fiber phases. The resistance to diffusion in the hollow fiber phase amounts to 76-80% of the total resistance. Nevertheless, the absorption rates of CO₂ into aqueous MAE solutions in this contactor are higher than those into aqueous solutions of sterically hindered 2-amino-2-methyl-1-propanol (AMP) in the stirred tank with a plane unbroken gas-liquid interface. The process of desorption of CO₂ from CO₂-loaded MAE solutions can be regarded as being controlled by diffusion and chemical reaction in both the stagnant film of the liquid phase and the liquid-filled pore of the hollow fiber phase under the slow or intermediate reaction regime. Both absorption and desorption rates under the simultaneous absorption-desorption operation in a single unit tend to approach the respective constant values as process time elapses. The total absorption rate here seems to be almost balanced with the total desorpion rate at the constant mass transfer rate periods.     

6万t/a离子膜烧碱装置新技术的攻关

介绍了离子膜烧碱生产中的新工艺、新技术的应用及产生的经济效益和社会效益。     

Site-directed mutagenesis of a calcium binding site modifies specifically the different biochemical properties of annexin I

All the functions of annexins in vitro as well as in vivo aremediated and probably regulated by calcium. We have used recombinantannexin I, synthesized by Escherichia coli, and we have performedsite-directed mutagenesis. We have mutated the endonexin foldof domain 2 that binds calcium. Mutations were performed inthis domain of the molecule because it perfectly matches thecalcium binding consensus sequence. The two glycines of thisfold were mutated into glutamic acid. The helix content andthe stability of the mutants are identical to those of the wild-type,suggesting that the mutations did not drastically affect thestructure of the protein. The two mutants showed modified calciumbinding affinities. However, the calcium binding affinity ofthe G131E mutant was far more altered than that of the G129Emutant. Furthermore, other biochemical properties of these mutantswere modified to different extents. The binding to phospholipidwas not seriously affected, whereas the selfassociation waslost by the G131E mutant. In the same way, liposome aggregationis conserved, but modified, while the calcium affinity measuredby equilibrium dialysis is dramatically altered.     

Influence of the composition of the binder and the carbonation on the zeta potential values of hardened cementitious materials

Electroosmotic experiments have been carried out on eight different mixes of hardened cementitious matrixes including concrete, mortar and pastes, different types of binders, carbonated and non-carbonated specimens and different test conditions. From these trials, the zeta potential values have been determined and the optimum experimental parameters and devices have been established. In addition, the influence of the composition of the binder on the zeta potential has been quantified indicating that higher amounts of Al₂O₃ in the binder lead to higher positive values of zeta potential, while the SiO₂ acts just on the opposite side. This has been explained in terms of the different i.e.p. (isoelectric point) for both oxides. Concerning the influence of carbonation, it increases the absolute value of the zeta potential toward more negative values; this behaviour has been attributed to the influence of the specifically adsorbed Ca²⁺ in the negative sites of the surface in the non-carbonated samples.