Preparation of CeO2-ZrO2 mixed oxide with high surface area and high thermal stability

Ceria-zirconia solid particles have been recognized as a key material of the automotive exhaust catalysts since they can release and uptake oxygen owing to the rapid reversible oxidation states of cerium between Ce³⁺ and Ce⁴⁺. Several methods have recently been described to prepare the CeO₂-ZrO₂ solid particles used in the catalysts. In this paper, a new coprecipitation method is used to prepare the CeO₂-ZrO₂ solid particles. The Ce-Zr alcogel is dried and calcined in flowing N₂ not in flowing air under atmospheric pressure. The results show that the ceria-zirconia sample calcined at 650 °C has high surface area over 90 m²g⁻¹, which drops to 40 m²g⁻¹ following treatment at 900°C.     

分置式牛津型斯特林制冷机的数值分析与实验验证

对分置式牛津型斯特林制冷机进行了数值计算 ,介绍了计算模型考虑到的众多不可逆因素。通过对计算结果与实验结果的对比 ,验证了本文数值计算的准确性 ,说明本文计算模型与数值处理方法是切实可行的     

智能工作站主机的MMPIS实验模型研究──一个全互连式结构MMPIS硬件环境的设计与实现

本文介绍中日国际合作开发研究的Ａ１型智能网（Ａ１型ＩＮ）智能工作站（ＩＷ）主机的并行推理硬件结构的实验模型设计与实现，给出了一种并行推理硬件支持环境实现方案和该方案在实现中若干问题的解决方法。     

非线性系统鲁棒吸引的动态补偿方法

考虑非线性不确定系统的鲁棒吸引问题,借助于动态输出反馈,构造了两类控制律。这两类控制律分别可使相应的闭环系统被一任意小的区域鲁棒吸引,或被一预先设置的区域有限吸引。     

Clinical study on effect of bushen shengxue paste in treating renal anemia patients

OBJECTIVE: To evaluate the therapeutical mechanism of Bushen Shengxue Paste (BSSXP) on anemia. METHODS: Chronic renal failure induced anemia patients were treated with BSSXP, clinical manifestation, anemia and renal function as indicators were observed in patients. The erythropoietin (EPO) and inhibition of colony-forming unit-erythrocyte (CFU-E) in patients' serum were determined by CFU-E in vitro. RESULTS: The patients' symptoms, renal function and anemia were improved after administration with BSSXP 1-2 course. EPO in serum was slightly increased. The inhibition of CFU-E in patient's serum was significantly decreased. CONCLUSIONS: BSSXP could improve the anemia degree, its mechanism might be through clearing the inhibitor of CFU-E in serum.     

The importance of electrochemistry-related etching in thegate-groove fabrication for InAlAs/InGaAs HFETs

For the first time, the surface metal on nonalloyed ohmic electrodes is found to significantly change the profiles of gate grooves, when resist openings are employed to monitor drain current during wet-chemical gate recess for sub-micron InAlAs/lnGaAs heterojunction field-effect transistors (HFETs). The surface metal of Ni enhances the etching rate in comparison with that in the absence of electrodes by a factor of 4 and 10, laterally and vertically, which is favorable to fabricate deep gate grooves with small side etching. The Pt surface metal, however, leads to preferential etching of InGaAs over InAlAs, which can be useful to realize large side etching. The existence of an electrochemistry-related etching component, which arises when the ohmic electrodes are present during recess etching, is considered to be responsible for these behaviors     

c-KIT expression enhances the leukemogenic potential of 32D cells

The growth of human leukemic cells in culture and in vivo is dependent upon the presence of hematopoietic growth factors. Most populations of human leukemic acute myeloblastic leukemia (AML) cells express c-Kit on their surface and respond to Kit ligand (KL) in culture. To determine if this interaction was of potential significance in vivo we used a mouse model system. 32D cells, a murine IL-3-dependent myeloid cell line, were rendered KL responsive by transfection of the murine c-Kit. After injection of 32D or 32D-Kit cells into syngeneic hosts, animals bearing 32D-Kit cells, but not 32D cells, became moribund and were killed. These animals had circulating leukemic blast cells, infiltration of bone marrow, spleen, brain, liver, lung, and kidney. Cells recovered from some of the animals continued to be dependent upon IL-3 or KL for growth while in other cases the cells were factor independent. This model illustrates that the constitutive expression of c-Kit enhances the leukemic potential of 32D cells. The model will be useful for studying the progression of leukemia in vivo and testing whether interruption of the interaction of Kit and KL can affect the growth of leukemic cells.     

Modified atmosphere packaging of a mixed prepared vegetable salad dish

The aim of this study was to design a modified atmosphere package for a mixed vegetable salad consisting of 75 g of cut carrot, 55 g of cut cucumber, 20 g of sliced garlic and 50 g of whole green pepper. Respiration data of all the components were combined with film permeability data to predict package atmospheres and design optimal packages for experimental testing for improved shelf-life of the produce. The optimal package avoided minimum O₂ and maximum CO₂ tolerance limits, and chilling injury temperatures for any component. A pouch form package made of 27 mm low density polyethylene developed a modified atmosphere of 2.0–2.1% O₂ and 5.5–5.7% CO₂, which was beneficial for all components and provided better quality retention than other test packages.     

基于局部差别的形态学边缘检测方法研究

图像边缘特征是图像最基本也是最重要的特征之一.图像边缘特征的提取一直是计算机视觉和图像处理领域的经典研究课题,在精确制导武器的制导图预处理中有着广泛地应用.针对经典的边缘检测算子不能很好地提取噪声图像边缘这一问题,在数学形态学的基础上,提出了一种边缘提取方法.利用局部差别准则确定图像中受噪声影响的像素点,并对其进行形态学操作,滤除噪声,保存边缘.实验表明,该算法不仅具有很好的边缘提取能力,还具有很强的抗噪能力.说明了该算法的有效性和实用性.