Axial offset control of PWR nuclear reactor core using intelligent techniques

Improved load following capability is one of the main technical performances of advanced PWR (APWR). Controlling the nuclear reactor core during load following operation encounters some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking, while the core is subject to large and sharp variation of local power density during transients. Axial offset (AO) is the parameter usually used to represent of core power peaking, in form of a practical parameter. This paper, proposes a new intelligent approach to AO control of PWR nuclear reactors core during load following operation. This method uses a neural network model of the core to predict the dynamic behavior of the core and a fuzzy critic based on the operator knowledge and experience for the purpose of decision-making during load following operations. Simulation results show that this method can use optimum control rod groups maneuver with variable overlapping and may improve the reactor load following capability.     

Radiation damage behavior of carbon/carbon composite in Low Earth Orbit environment

To understand the degradation behavior of Carbon/Carbon(C/C) composite in LEO radiation environment, groups of 2D-C/C composites samples were exposed to ground-based Low Earth Orbit(LEO) simulating facilities. The LEO radiating environment covers part of Van Allen inner belt, which contains atomic oxygen(AO) and high-energy proton radiating regions. These two kinds of radiating sources were arranged for simulating the real LEO radiating conditions regarding to the first orbit movement speed of serving space shuttles. Changes of micro-structure, mass loss, surface roughness, chemical construction and thermal physical properties after environmental assessment were analyzed and compared to understand the damage behavior of LEO radiation on C/C composite. It was found that AO is the main factor of mass loss in LEO radiating particles. The charged high-energy protons have an aggravating damage ability with energetic AO, damage situations of degree in orbit down process is more serious than in orbit rising process. The LEO radiation damage mechanisms of C/C composite are revealed and expounded either.     

Co3O4/4A分子筛活化PMS处理高盐AO7废水研究

采用浸渍-焙烧法制备Co₃O₄/4A分子筛复合催化剂,用于活化过一硫酸盐（PMS）处理高盐酸性橙7（AO7）废水。采用扫描电镜、X-射线衍射仪、红外光谱仪等对复合催化剂进行表征,同时考察其稳定性。考察复合催化剂活化PMS对AO7模拟废水的处理效果,结果表明,当Co₃O₄/4A分子筛投加量为0.2 g/L、PMS投加量为0.7 mmol/L、pH为9时,高盐（Na₂SO₄,10 g/L）废水中AO7浓度可在20 min内由15 mg/L左右降至接近0,去除率达99%以上,同时催化剂钴离子溶出量约为0.36 mg/L,低于《地表水环境质量标准》（GB3838-2002）中规定的1 000μg/L。     

高精度远程隔离型多路AI/AO电路设计

设计了一种基于TMS320LF2407的模拟量输入电路(AI)和模拟量输出电路(AO),成功解决了大型远程工业控制系统中存在的三个问题.实际的工程应用表明,该电路具有良好的应用前景.     

LD端面泵浦的1.57μm内腔式OPO

1.57 μm波长激光为人眼安全波长激光。将KTP晶体置于一个由LD端面泵浦、声光调Q的Nd:YVO4晶体双凹谐振腔内,利用KTP表面镀膜建立了内腔式OPO,实现了重复率在5～40 kHz范围内1.57 μm脉冲激光的稳定输出。实验结果表明,激光的阈值将随声光调Q器重复率的增加而升高,重复率为5 kHz时得到最低阈值1.52 W。重复率为15 kHz、泵浦功率为3.7 W时,输出光平均功率为305 mW,脉冲宽度50 ns,峰值功率400 W。     

丙烯腈装置废气焚烧技术的国产化应用

主要描述丙烯腈装置中废气焚烧(AOGI)技术的国产化。通过上海石化集团公司丙烯腈装置应用实例,阐述了我们通过对国外工艺包技术的消化吸收,自主开发出国产化技术,并在装置实际运用中取得了良好的效果,和引进工艺包相比减少了大量投资。     

The interaction of sesamol with DNA and cytotoxicity,apoptosis, and localization in HepG2 cells

Sesamol, a nutritional antioxidant phenolic compound present in sesame seed, has a potential therapeutic molecule effect against cancers. In this study, the interaction between sesamol and DNA was investigated by employing ultraviolet/visible (UV/Vis), fluorescence, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR), and molecular modeling. The fluorescence analysis indicated that the fluorescence quenching mechanism of sesamol by calf thymus DNA (ctDNA) occurred through static quenching. The UV/Vis, CD, FT-IR spectra and molecular docking results implied that the primary binding mode was minor groove binding. Furthermore, the intracellular interaction of sesamol with DNA and its bioactivity effect were explored. The cell activity results demonstrated that sesamol induced hepatic cell line (HepG2) death. The acridine orange (AO)/ethidium bromide (EB) staining assay and DNA fragmentation confirmed that sesamol could efficiently induce the apoptosis of HepG2 cells. Moreover, addition of sesamol to HepG2 cells resulted in nuclear localization, as visualized by confocal microscopy.     

空间聚合物基体表面原子氧防护技术研究进展

低地球轨道(Low Earth Orbit,LEO)中,强氧化性、大通量、高能量的原子氧(atomic oxygen,AO)会对航天器表面材料造成极大的破坏。特别是聚合物材料,受AO侵蚀后易氧化降解,造成光学、电学和力学等性能退化,影响航天器的正常工作并缩短其使用寿命。从LEO环境中抗AO侵蚀材料研究的理论基础出发,评述了无机、有机及复合涂层的制备方法和各自的优缺点,目前存在的问题,以及聚合物基体表面涂层开裂与界面剥离失效机理研究的重要性。从目前的研究可以看出,具有自我修复功能的有机或无机功能涂层,以及与原子氧反应时能产生具有保护性能的稳定氧化物或其他稳定表面结构的涂层,是今后的研究方向。应将聚合物基体和涂层作为整体进行研究,充分研究涂层与基体间的界面效应和失效机理。在抗AO新材料研究领域,以聚酰亚胺材料为例,简述了含磷、含硅、含锆聚酰亚胺的研究进展,以及从基础研究到工程化应用还亟待解决的关键问题和工艺技术。希望该综述为发展新的先进防护涂层和新材料体系提供一些可借鉴的研究思路。     

使用 mentalray 渲染打造游戏场景

文章主要讲解了怎样在Maya制作一个游戏场景的过程.     

利用相切条件研究TeO2晶体反常声光衍射几何关系

利用相切条件推出了计算TeO2晶体反常声光衍射几何关系的方程,给出了zt平面内光波矢量的入射角和衍射角、超声极值频率、声光优值等参数随超声离轴角而变化的曲线. 该计算方法比传统的求解Dixon方程的方法更简捷和精确. 计算结果表明,TeO2反常声光器件的中心频率存在最小阈值;对于相同的中心频率,1级衍射状态优于1级衍射状态. 为了设计器件的方便,还列出了中心频率在200MHz以下TeO2反常声光器件的各设计参数及性能参数.