Hydrogen production from coal by separating carbon dioxide during gasification

Hydrogen generation during the reaction of a coal/CaO mixture with high pressure steam was investigated using a flow-type reactor. Coal, CaO and CO reactions with steam, and CO₂ absorption by Ca(OH)₂ or CaO occurred simultaneously in the experiment. It was found that H₂ was the primary resultant gas, comprising about 85% of the reaction products. CO₂ was fixed into CaCO₃ and CO was completely converted to H₂. Pyrolysis of the coal/CaO mixture carried out in N₂ was also examined. The pyrolysis gases were compared with gases produced by general coal pyrolysis. While general coal pyrolysis produced about 14.7% H₂, 50.5% CH₄, 12.0% CO and 12.0% CO₂, the gases produced from coal/CaO mixture pyrolysis were 84.8% H₂, 9.6% CH₄, 1.6% CO₂ and 1.1% CO.     

G-lambda: Coordination of a Grid scheduler and lambda path service over GMPLS

At iGrid2005, we conducted a live demonstration where our Grid scheduling system co-allocated computing and network resources with advance reservation through Web services interfaces using the Grid Resource Scheduler (GRS), the Network Resource Management System (NRM), which is capable of GMPLS network resource management, and a GMPLS-based network test-bed, for the first time. The goal of the G-lambda project is to define a standard Web services interface (GNS-WSI) between GRS and NRM that is acceptable for both application service providers and commercial network operators, and which can be used as a tool for realizing new and emerging commercial services.     

Interfacial microstructure of Si3N4/Si3N4 brazing joint with Cu–Zn–Ti filler alloy

In this study, Si₃N₄ ceramic was jointed by a brazing technique with a Cu–Zn–Ti filler alloy. The interfacial microstructure between Si₃N₄ ceramic and filler alloy in the Si₃N₄/Si₃N₄ joint was observed and analyzed by using electron-probe microanalysis, X-ray diffraction and transmission electron microscopy. The results indicate that there are two reaction layers at the ceramic/filler interface in the joint, which was obtained by brazing at a temperature and holding time of 1223 K and 15 min, respectively. The layer nearby the Si₃N₄ ceramic is a TiN layer with an average grain size of 100 nm, and the layer nearby the filler alloy is a Ti₅Si₃N_x layer with an average grain size of 1–2 μm. Thickness of the TiN and Ti₅Si₃N_x layers is about 1 μm and 10 μm, respectively. The formation mechanism of the reaction layers was discussed. A model showing the microstructure from Si₃N₄ ceramic to filler alloy in the Si₃N₄/Si₃N₄ joint was provided as: Si₃N₄ ceramic/TiN reaction layer/Ti₅Si₃N_x reaction layer/Cu–Zn solution.     

Neurite outgrowths of neurons with neurotrophin-coated carbon nanotubes

Multiwalled carbon nanotubes (CNTs) coated with neurotrophin were used to regulate the differentiation and survival of neurons. Neurotrophin (nerve growth factor [NGF] or brain-derived neurotrophic factor [BDNF]) was covalently bound to CNTs modified by amino groups using a 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) reagent. The CNTs coated with NGF or BDNF promoted the neurite outgrowths of neurons in the same manner as soluble NGF and soluble BDNF. By enzyme-linked immunosorbent assay (ELISA), we demonstrated that neurotrophin-coated CNTs carry neurotrophin. These results suggest that neurotrophin-coated CNTs have biological activity and stimulate the neurite outgrowths of neurons.     

反算法的进一步探讨

日本神户大学樱井春辅教授的反算法是应用现场测得的有限个相对位移,通过反算的方法,求出山体的初始应力和弹性模量,进一步求出山体和衬砌任意点的应变和位移。并把计算结果及时反馈到施工中,进行合理的施工管理。此方法应用于毛洞情况是正确的;对于有衬砌的隧道,本文提出三方面的改进意见供进一步探讨。     

Structures and microhardness of nanostructured Cr–Ni-sputtered alloy

Nanostructured Cr–xNi alloys were prepared by magnetron sputtering in low pressure argon gas, where x varied from 0 to 20 at%. The structure and microhardness of the alloys were observed by TEM (microscopy) and Vickers hardness testing, respectively. The crystal structure of the sputtered alloys was BCC. The addition of nickel to chromium decreases the grain size of the Cr–Ni alloys and the grain sizes of the alloys changed from 88 nm for Cr to 30 nm for Cr-20 at% Ni alloys. The microhardness of the Cr–Ni alloys showed the maximum around 5 at% Ni. The increase in nickel content above 5 at% lowers the microhardness of the alloys, although the grain size of the Cr–Ni decreases. The abnormal tendency against grain size change was discussed in terms of the characteristics of the grain boundaries in the alloys.     

Ab Initio Calculations of the Atomic and Electronic Structure of β-Silicon Nitride

The atomic and electronic structure of the β-silicon nitride (β-Si₃N₄) crystal have been determined using the ab initio pseudopotential method based on the density functional theory. We have obtained the stable lattice parameters and the stable positions of 14 atoms in the unit cell for the structure P 6₃/ m for the first time. The electronic structure and the charge distribution indicate that the Si–N bond has both ionic and covalent characters. The band structure is in good agreement with the other first-principles results and consistent with the experiments.     

Preparation of CaCO3/polymer composite films via interaction of anionic starburst dendrimer with poly(ethylenimine)

Summary The CaCO₃/poly(ethylenimine) composite film was obtained in the presence of anionic poly(amidoamine) (PAMAM) dendrimer (G=3.5), whereas the formation of composite film was not observed without PAMAM dendrimer or with PAMAM dendrimer (G=1.5) judging from the results of scanning electron micrographs (SEM). The crystal phase of the CaCO₃ film formed was found to be calcite by FT-IR and XRD analysis. The adsorption of PAMAM dendrimer on poly(ethylenimine) film might cause local high concentration of calcium ion and induce a formation of the CaCO₃ film. Received: 23 October 2000/Accepted: 10 November 2000     

Merging formation and current amplification of field‐reversed configuration

The merging formation of the field‐reversed configuration (FRC) has been developed in the TS‐3 merging experiment, leading us to a new scenario of FRC slow formation, heating and current amplification. Two force‐free spheromaks with opposing toroidal fields were merged together in the axial direction to form a high‐β FRC with higher efficiency than the conventional field‐reversed theta‐pinch method. This unique relaxation from the force‐free (β ∼ 0.05 − 0.1) spheromaks to the high‐β (β ∼ 0.7 − 1) FRC is attributed to the conversion of toroidal magnetic energy into ion thermal energy through the reconnection outflow. A central ohmic heating (OH) coil worked successfully to amplify the FRC plasma current by a factor of 2. Toroidal mode analysis of magnetic structure indicated that the tilting stability of the oblate FRC was provided by an ion kinetic effect. This oblate FRC is also useful as an initial equilibrium to produce a high‐β_p spherical tokamak (ST) with diamagnetic toroidal magnetic field, suggesting the close relationship between FRCs and high‐β_p STs in the second stable region of the ballooning mode. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.