B位异价离子(Al,Cr)置换对Li3xLa2/3-xTiO3离子电导率的影响

研究了B位Al,Cr异价离子置换对Li_3xLa_2/3-xTiO₃(x=0.13)离子电导率的影响。结果表明:用适量离子半径较小的Al³⁺(0.535A)置换Ti⁴⁺(0.605A)可有效地提高其离子电导率,当B位铝离子的置换量为y=0.02时,组分为(Li_0.39La_0.54)_1+y/2Al_yTi_1-yO₃的材料其室温下的体离子电导率σ_b=(1.58±0.01)×10^-3S·cm^-1,这一结果是迄今为止钙钛矿锂离子导体材料文献报道的最好水平。然而,分析结果表明,离子电导率的提高难以用锂离子迁移“瓶颈”尺寸的变化,TiO₆八面体张缩能力及A位阳离子和空位的有序性来解释,因B位异价离子置换而引发的Li⁺离子键强度的变化被认为是导致锂离子电导率提高的原因。     

Runaway Electron Suppression by ECRH and RMP in KSTAR

We have observed reduction of the runaway electron synchrotron radiation, hard X-ray (HXR) intensity, and HXR energy after applying 110 GHz 2nd harmonic electron cyclotron resonant heating (ECRH) during runaway electron (RE) discharges at low density with startup runaway electrons. However, we did not see a significant reduction of X-rays from 170 GHz 2nd harmonic ECRH at a higher field. A recently installed IR TV camera was used to observe the forward cone of synchrotron radiation from high energy REs in KSTAR. We have observed changes to the synchrotron images and reduction of the HXR by application of resonant magnetic perturbations (RMP) from in-vessel control coils (IVCC) installed inside KSTAR in the n = 1 configuration.     

Endoscopic focal modulation microscopy

We present endoscopic focal modulation microscopy (FMM) for minimally invasive imaging of deep tissue with high contrast, and then compare the results using endoscopic confocal microscopy (CM). Deep tissue imaging is achieved using a needle‐like endoscopic probe based on gradient‐index (GRIN) lenses. A tissue‐like phantom with fluorescent micro‐beads and rat kidney tubules were imaged through the endoscopic probe with FMM. FMM effectively rejected the background signals from the out‐of‐focus plane, thereby enhancing the image contrast and the optical sectioning ability. The combination of the GRIN endoscopic probe and FMM provides deep tissue imaging with better contrast than endoscopic CM.     

RHEOLOGICAL PROPERTIES OF HOT PEPPER-SOYBEAN PASTE

Rheological properties of fermented hot pepper-soybean paste (HPSP) were evaluated at different total solid contents (TS, 43.6-54.7%) and temperatures (10-40C). HPSP samples at 20C are highly shear thinning fluids (n=0.25-0.33) with large magnitudes of Casson yield stresses (106-573 Pa). Consistency index (K) and apparent viscosity (η_a,20) increased with increase in TS. Apparent viscosity of HPSP obeyed the Arrhenius temperature relationship. The magnitudes of activation energy (7.6-20.4 kJ/mole) for HPSP increased with increase in TS. A single equation, combining the effects of temperature and concentration on η_a,20, was used to describe flow behavior of HPSP. The time-dependent model of Weltman was found to be most applicable (R²= 0.97-0.99) for HPSP. Storage (G') and loss (G") moduli increased with increase in TS, while complex viscosity (η*) decreased. Magnitudes of G'were higher than those of G" over the entire range of frequencies (ω).     

Influence of potassium pyrophosphate in electrolyte on coated layer of AZ91 Mg alloy formed by plasma electrolytic oxidation

The effect of potassium pyrophosphate in the electrolyte on plasma electrolytic oxidation (PEO) process for AZ91 Mg alloy was investigated. The morphologies and chemical compositions of the coating layer on the AZ91 Mg alloy were evaluated and corrosion resistance was also estimated by potentiodynamic polarization analysis. The coating layer on AZ91 Mg alloy coated from the Bath 2 containing 0.03 mol/L of potassium pyrophosphate for 360 s exhibited considerably dense structure and contained 11%–18% (mass fraction) of phosphorous. The higher content of phosphorous of coating layer coated from Bath 2 could be detected at the bottom of oxide layer, which strongly implied that the phosphorous ion might be concentrated at the barrier layer. Corrosion potential of coating layer of AZ91 Mg alloy increased and corrosion current density decreased with increasing the concentration of potassium pyrophosphate. The polarization resistance (R_p) of coating layer of AZ91 Mg alloy coated from Bath 2 was 4.65×10⁷ Ω/cm², which was higher than that (R_p=3.56×10⁴ Ω/cm²) of the sample coated from electrolyte without potassium pyrophosphate. The coating layer coated from Bath 2 containing 0.03 mol/L potassium pyrophosphate exhibited the best corrosion resistance.     

高速旋转电弧传感器的数学模型

以气保护焊接系统的数学模型和HALMOY焊丝熔化模型为基础,对高速旋转电弧传感器进行数学建模。利用该数学模型模拟焊接电流、弧长和焊丝伸出长度随时间的变化规律。实际焊接试验显示,模拟焊接电流与实际焊接电流波形高度吻合,说明建立的数学模型是准确的。结果表明,高速旋转电弧焊接时,弧长的变化较焊丝伸出长度的变化更为显著。利用每个电弧旋转周期内左半周与右半周平均电流值的差,可以判断焊枪的偏差量及其方向,同时还可根据平均电流值的大小来检测角接终止点。所建立的模型对于高速旋转电弧传感系统的设计具有指导意义。     

Formation of lamellar structure in gamma titanium aluminide

Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.     

GA BASED SIMULATION OF IMMUNE NETWORKS APPLICATIONS IN STRUCTURAL OPTIMIZATION

Genetic algorithms have received considerable recent attention in the optimal design of structural systems. These algorithms derive a computational leverage from an intrinsic pattern recognition capability, whereby patterns or schemata associated with a high level of fitness are identified and evolved at a near-exponential growth rate through generations of simulated evolution. This highly exploitative search process has been shown to be extremely effective in searching for schema that represent an optimum, requiring only that an appropriate measure of fitness be defined. This exploitative pattern recognition process is also at work in another biological system - the immune system responsible for recognizing antigens foreign to the system and generating antibodies to combat the growth of these antigens. The paper describes key elements of how the functioning of the immune system can be modelled in the context of genetic search. It then provides an overview of the implications of this model in improving the convergence characteristics of genetic search, in particular, in the context of handling design constraints.     

用Al或Mo/Al/Mo低阻材料改善4-Mask工艺中Al腐蚀的方法

为了减少制造工艺的过程,改进的4-Mask工艺中采用Al基的数据线已得到进一步的完善。但这个工艺仍存在很多问题,主要是为减少工艺过程,而引入干法刻蚀对Al有腐蚀作用。本文应用CF4/O2等离子体处理,很好地阻止了对Al的腐蚀,得到很好的效果,对改进后4-Mask工艺的进一步应用具有非常重要的意义。