Mechanisms of solidification and subsequent embrittlement of dephosphorization slag used in a subtidal zone as an alternative to sea sand and prevention of solidification by adding dredged soil

In the recent years, steelmaking slag is attracting attention as suitable materials for restoration of estuary ecosystems. However, there is concern about solidification when the material is applied to create seagrass beds. In this study, dephosphorization slag (DePS) was immersed into seawater for 10 months to examine the solidification processes and its mechanisms to control the strength of solidification. The hypothesis in this study is that solidification could be alleviated by adding dredged soil to the DePS. After 5 months of immersion, the shear strength of the DePS increased from 1.8 to 5.0 kN/m²; however, its shear strength decreased significantly to 3 kN/m² after 10 months. Furthermore, after 5 months, reddish color was observed on the surface of the DePS, whereas the color of the surface of the DePS turned black at 7 months under reducing condition with covering by mud. To validate the results, we carried out an additional study, in which the DePS was immersed in seawater, and the solidified DePS was subsequently treated with Na₂S; the increase and decrease of the shear stress of DePS were reproduced. The solidified DePS before and after exposure to reducing conditions was also analyzed using a combination of microanalysis with an electron probe and Mössbauer spectroscopy. These analyses showed that the solidification was caused by the formation of bridges that composed of iron oxyhydroxides, whereas the subsequent embrittlement of the solidified DePS was attributed to changing in the chemical species of iron.     

Glass Microspheres for Optics

Preparation and application of glass spheres as resonators are discussed. Surface-tension mold (StM) and localized-laser heating (LLH) techniques have been developed to fabricate glass super spheres and true spheres, respectively. These prepared glass spherical particles have been examined to evaluate their suitability for whispering gallery mode (WGM) oscillators or laser cavities. Super spherical glass acts as a WGM oscillator using its equatorial plane. An equatorial circle roundness > 0.99 provides a high Q-value to lead laser oscillation. LLH demonstrates its excellent capability to prepare “true spheres” on a transparent substrate under gravity. A tellurite glass sphere prepared by the LLH technique exhibits a few-mW-order threshold for lasing at the 1.06-μm region. An added-on terrace and an installed bubble in the sphere serve as an input/output gate and as a “non-WGM” coupling input gate for laser action, respectively. Glass is showed to have strong potential with respect to both preparation and utilization of spherical shapes for optics.     

Practical selection of emission lines of He I to determine the photon absorption rate

A combination of helium line intensities and a collisional radiative model has been used to measure electron density and temperature. However, radiation trapping of resonance lines may disturb the measurements due to disturbances in the population distribution of helium atoms. In this study, we show that the principal contribution of radiation trapping in helium plasma can be evaluated by additionally measuring one or two specific line intensities from the singlet state. The inclusion of the effects of radiation trapping sufficiently compensates for anomalous increases in the electron density and temperature, and consequently yields proper values. An experiment was performed in the divertor simulator NAGDIS-II, and the method's validity was confirmed by comparing the spectroscopically obtained results and the values from the electrostatic probe method.     

Measurement of ion and electron temperatures in plasma blobs by using an improved ion sensitive probe system and statistical analysis methods

We have measured ion temperature as well as electron temperature in plasma blobs observed in a linear plasma device by using an improved ion sensitive probe. Current-voltage characteristics of the ion sensitive probe inside and outside plasma blobs were re-constructed with a conditional sampling method. It is clearly found that both ion and electron temperatures in plasma blobs decrease more slowly in a cross-field direction than those in a bulk plasma without plasma blobs.     

Hydrodynamic properties on superfluid3He in high magnetic fields up to 12 tesla

Using a torsional oscillator, superfluid fraction and viscosity of superfluid³He were measured in the A₁ and the a₂ phase up to 12 Tesla below 1 mK in the pressure of 29 bar. This is the first measurement in the high magnetic field region in a well defined geometry and in a controlled texture. The a₁ and the a₂ transition were seen clearly in the torsional oscillator frequency and amplitude. Two GL parameters, ₂₄₅ and ₂₄, are independent of field up to 12 Tesla. ₂₄₅ is 1.18 from the A₂ phase measurements, which agree with those from heat capacity measurement. While ₂₄ is 3.08 from the a₁ phase, which is smaller than that from recent spin entropy wave measurement.     

Line profile reconstruction from simultaneously recorded secondary and backscattered electron signals

We propose a reconstruction method of surface morphology using a combination of secondary and back-scattered electron signals from the scanning electron microscope (SEM). Compared with multiple-detector methods, the proposed system requires only conventional secondary and backscattered electron detectors for a line profile reconstruction in one direction. This method is an application of genetic algorithms to the measurement of surface morphology in SEM. We use the chi-square distribution of the reconstruction error as the objective function within a scheme to minimize the number of vertices in the reconstructed surface profile. (The reconstruction error is the relative difference between the calculated and experimental data.) To evaluate the efficacy of our method, a surface profile is successfully reconstructed from a pair of line scans across the center of a latex particle.     

晶圆干燥缺陷的机理与控制

长期以来,人们对于硅片在经过HF湿法处理之后出现的水印早已有所认识,尤其是图形包含亲水和疏水层时最为明显。我们系统地研究了经过HF后道处理之缺陷形成的机理,并确认了与先前报道的水印截然不同的缺陷类型。根据X射线和其它分析表明,认为这些缺陷与周围环境残余的汽相HF和随后的晶圆表面反应有关。根据反应腔室HF浓度的不同可以产生不同类型的缺陷。由于水印是由硅在水中的氧化和随后产生的氧化物的分解形成的,少量的HF具有加速这个过程的效果。形成不同缺陷的条件,还有避免这些缺陷的策略均得以认定。正确的排空管理是一个关键的因素。最后发现,重参杂的硅更易产生缺陷。     

Hybrid peptides constructed from RES-701-1, an endothelin B receptor antagonist, and endothelin; binding selectivity for endothelin receptors and their pharmacological activity

Hybrid peptides were constructed from endothelin B receptor (ET(B)) selective antagonist RES-701-1 (1) and endothelin (ET-1). They have N-terminal 10 amino acids derived from 1 and C-terminal 10 amino acids derived from ET-1. RES-701-1(1-10)-[Ala15]ET-1(12-21) and its analogues substituted or truncated at the residues derived from RES-701-1 had proved to possess high receptor binding activity selective for ETB as well as 1. Substitutions at the residues derived from ET-1 had produced some analogues that possessed high affinity not only for ETB but for ETA. Although all analogues had antagonistic effects on ETA, some analogues had proved to function as agonist on ETB confirmed by the changes in intracellular calcium concentrations of ET receptor-transfected COS-7 cells. We have found four types of ET receptor-binding peptides: (1) ETB-selective agonist with weak ETA antagonism (3, KT7421); (2) ETB-selective antagonist with weak ETA antagonism (29, KT7539); (3) ETB agonist with potent ETA antagonism (27, KT7538); and (4) non-selective ETA/ETB antagonist (26, KT7540).