东亚现代城市之始——英系租界与居留地的殖民主义规划及管理比较研究

从口岸体系和殖民主义比较角度研究沪鹭穗津汉浔镇等英系租界与居留地的规划及管理。巴夏礼对英系口岸、租界和居留地的开辟、规划、管理和现代化起关键作用。它们受英驻东亚外交体系管控,遵循类似的英系殖民主义空间规划与城市管理模式。公使和工部局颁布的市政与建筑法规确保了高效的殖民主义空间生成。殖民主义影响、口岸体系互动推动了近代东亚城市空间的外来与自主现代化。跨文化的空间共同体遗存是潜在的系列世界遗产。     

Titanium Fiber Plates for Bone Tissue Repair

Titanium plates are widely used in clinical settings because of their high bone affinity. However, owing to their high elastic modulus, these plates are not suitable for bone repair since their proximity to the bone surface for prolonged periods can cause stress shielding, leading to bone embrittlement. In contrast, titanium fiber plates prepared by molding titanium fibers into plates by simultaneously applying compression and shear stress at normal room temperature can have an elastic modulus similar to that of bone cortex, and stress shielding will not occur even when the plate lies flush against the bone's surface. Titanium fibers can form a porous structure suitable for cell adhesion and as a bone repair scaffold. A titanium fiber plate is combined with osteoblasts and shown that the titanium fiber plate is better able to facilitate bone tissue repair than the conventional titanium plate when implanted in rat bone defects. Capable of being used in close contact with bone for a long time, and even capable of promoting bone repair, titanium fiber plates have a wide range of applications, and are expected to make great contributions to clinical management of increasing bone diseases, including bone fracture repair and bone regenerative medicine.     

Synthesis of composite electrode materials of FeOOH-based particles/carbon powder and their high-rate charge-discharge performance in lithium cells

Composite electrode materials of FeOOH-based particles and carbon powder were prepared with and without heat treatment of composite powder. The composite powder was obtained by hydrolyzing mixed aqueous solutions of FeCl₃, Ti(SO₄)₂ and electron conducting carbon powder as acetylene black (AB) or Ketjen black (KB). FeOOH-based materials formed in the presence of Ti(IV) ions became amorphous and/or low crystalline structure. The composite powder worked as lithium insertion electrode materials in lithium cells using nonaqueous electrolytes including lithium ions. The electrodes exhibited a good cycle performance at large charge-discharge current densities over 5 mA cm⁻² (4 A g⁻¹ per weight of active material). In addition, it was found that the cycle performance was effective process to be improved by the heat treatment of the composite materials. The composite materials such as amorphous FeOOH, α-Fe₂O₃, TiO₂ and electron conductive powder obtained by the heat treatment are one of the promising candidates as electrode materials for energy storage devices, such as lithium-ion batteries and hybrid electrochemical supercapacitors.     

Changes in electronic states of platinum-cobalt alloy catalyst for polymer electrolyte fuel cells by potential cycling

Changes in the electronic states of platinum-cobalt (Pt-Co) alloy catalysts through potential cycling between 0.6 and 1.0 V were investigated by X-ray photoemission spectroscopy (XPS) using synchrotron radiation. The electrochemical surface area loss and the particle size growth of the Pt catalyst were larger than those of the Pt-Co alloy catalyst. Pt 4f XPS spectra of the Pt-Co alloy catalyst do not show any change through the potential cycling, indicating that most part of Pt is stable during the potential cycling. Larger amount of Pt(OH)₂ existed in the initial MEA of the Pt catalyst than the Pt-Co alloy catalyst, indicating that the Pt catalyst has a tendency to be oxidized. The Pt(OH)₂ decreased and metallic platinum increased in the cycle-tested MEA, suggesting that the Pt(OH)₂ dissolved and re-deposited as metallic states. The oxidation tendency explains the less durability of the Pt catalyst than the Pt-Co alloy catalyst. Co 2p XPS spectra imply that cobalt is absent on the surface of the catalyst particles and the Pt skin layer is thicker than 1.4 nm (4 mono-layers). The absence of the cobalt oxide in the cycle-tested MEA demonstrates that the Pt-Co core under the Pt skin layer is stable during the potential cycling.     

氢气渗透Nb基合金的设计及特性表征

在Nb40Ti30Ni30合金的初生相(Nb,Ti)和共晶相连线上制作Nb-Ti-Ni合金.研究表明,上述直线上的合金由初生相和共晶相构成,氢渗透度Ф随Nb浓度和初生相(Nb,Ti)体积分数的增大而升高,氢渗透合金的Nb浓度扩展至68 mol%.Nb68Ti17Ni15合金由74%(体积分数)的初生相(Nb,Ti)和26%(体积分数)的共晶相{(Nb,Ti)+TiNi}组成,氢渗透度最大Ф673K达到4.91×10-8mol H2m-1s-1Pa-0.5,是Nb40Ti30Ni30合金的氢渗透度Ф673K的2.5倍,纯钯金的氢渗透度Ф573K的3.5倍.     

Assessment of cracks existing in the strain concentrated region from a viewpoint of brittle fracture

The significance of cracks existing in the strain concentrated region is discussed from a viewpoint of brittle fracture.In this study, the J-integral, of which the mathematical treatment is easier and stricter than that of COD (crack opening displacement) is considered as the fracture parameter. Also, averaged local strain, , in the strain concentrated region without a crack is considered as the mechanical parameter which characterizes the state of the elastic-plastic region generated near the stress raiser. The relation between the J-integral of the cracked body and the local strain is investigated experimentally and theoretically with the aid of the elastic-plastic finite element analysis.Brittle fracture tests on the strain concentration models of the four kinds of the structural steel (SM41, SM50, HT80 and A508 C1.3) show that a newly proposed J design curve provides a good estimation for the strength of brittle fracture from a crack existing in the stress/strain concentrated region.     

Importance of water content in formation of porous anodic niobium oxide films in hot phosphate-glycerol electrolyte

Niobium has been anodized at a constant current density to 10 V with a current decay in 0.8 mol dm⁻³ K₂HPO₄-glycerol electrolyte containing 0.08-0.65 mass% water at 433 K to develop porous anodic oxide films. The film growth rate is markedly increased when the water content is reduced to 0.08 mass%; a 28 μm-thick porous film is developed in this electrolyte by anodizing for 3.6 ks, while the thickness is 4.6 and 2.6 μm in the electrolytes containing 0.16 and 0.65 mass% water respectively. For all the electrolytes, the film thickness changes approximately linearly with the charge passed during anodizing, indicating that chemical dissolution of the developing oxide is negligible. SIMS depth profiling analysis was carried for anodic films formed in electrolyte containing ∼0.4 mass% water with and without enrichment of H₂¹⁸O. Findings disclose that water in the electrolyte is a predominant source of oxygen in the anodic oxide films. The anodic films formed in the electrolyte containing 0.65 mass% water are practically free from phosphorus species. Reduction in water content increased the incorporation of phosphorus species.     

Ultra Accelerated Quantum Chemical Molecular Dynamics Study on Ethylene Polymerization Reaction Using CpSiH2NHTiCl2—Constrained Geometry Catalyst

The ethylene polymerization process using constrained geometry catalyst CpSiH₂-NH-TiCl₂ (CGC) was investigated by ultra accelerated quantum chemical molecular dynamics (UA-QCMD). We observed that the co catalyst MAO reacted with Ti CGC and forms ion pair within 85 fs. With the coordination of ethylene monomer the MAO-CGC ion pair dissociated and once the initial ethylene insertion has taken place, the further ethylene insertion occurring with a less energy barrier, is in good agreement with experimental findings.     

Deposition of Bismuth Telluride Thick Film by Solidification under Centrifugal Pressure

Bismuth telluride alloys—Bi_0.5Sb_1.5Te₃ and Bi_1.8Sb_0.2Te_3.33Se_0.17—have been deposited on polycrystalline zirconia via solidification under centrifugal pressure. The crystal growth under centrifugal pressure was a process in which the starting powders charged in the groove patterns of the substrates were first melted and then solidified under centrifugal acceleration of 10⁴ m/s². This new process offers c-axis-oriented films with a thickness of more than 100 μm. A mirror-like surface is another characteristic feature of these films. Owing to their orientation, reasonable power factors such as 4.2 mW/m K² and 2.7 mW/m K² (in plane) were obtained for p- and n-type films, respectively.