工业自动化控制系统的抗干扰技术分析

分析了干扰感应模型,指出常见的工业自动化控制系统的干扰源包括辐射干扰、传导干扰和设计施工引起的干扰,分析了这些干扰的产生机理;指出应从设计和现场施工两方面采取抗干扰措施,设计阶段要考虑电源设计、接地系统设计、管线设计、器件选择、软件设计等因素,并给出了常见的抗干扰措施;以某燃气站控制系统为例介绍了抗干扰措施在实际工业现场中的应用方案,验证了合理的抗干扰措施可有效降低干扰,保证工业自动化控制系统的可靠运行。     

X-ray spectroscopy and local structures in glasses

X-ray spectroscopy which is a combination of two techniques, namely x-ray absorption near edge structure (xanes) and extended x-ray absorption fine structure (EXAFS) analyses, is a unique technique for the study of local structures in glasses. Availability of synchrotron radiation sources has made the technique quite attractive and useful because the photon flux from synchrotrons is very intense and polarized. In this article, a brief summary ofxanes andEXAFS techniques is given along with a few applications to the study of local structures in glasses. Communication No. 323 from Solid State and Structural Chemistry Unit.     

表面n沟CCD的电离辐射损伤

本文报道了150光敏元表面n沟CCD(电荷耦合器件)在不同能量电子和γ射线辐照后的电离辐射效应。试验结果表明,转移失效率在≤10Gy时已明显增大。但大多数器件在累积剂量≤50Gy时,通过调整“胖零”注入仍可工作。在高剂量辐照期间,不同栅偏压器件的转移效率退化存在较大差异。应用高频和准静态C-V技术分析了参数退化的原因。     

基于NWP辐照度斜面转换的光伏功率预测方法

短期光伏功率预测统计方法一般采用数值天气预报(numerical weather prediction, NWP)的水平辐照度, 而不是倾斜安装的光伏板上接收到的斜面辐照度, 导致预测精度不足。针对这一问题提出新的辐照度斜面转换方法, 先将散射辐射分为属性不同的分子散射、米散射, 再对两者分别进行斜面转换; 采用该方法将NWP水平辐照度转换为NWP斜面辐照度, 再基于NWP斜面辐照度进行光伏功率建模与预测。算例结果显示, 本方法的预测精度(均方根误差为10.25%、相关性系数为0.914 0)高于直接采用NWP水平辐照度的传统方法。     

柔性基电磁屏蔽材料的研究进展

本文介绍了电磁屏蔽材料的屏蔽原理、电磁屏蔽损耗材料的类型及性能,总结了柔性基电磁屏蔽材料的制备方法及其研究进展。     

Out-of-Field Hippocampus from Partial-Body Irradiated Mice Displays Changes in Multi-Omics Profile and Defects in Neurogenesis

The brain undergoes ionizing radiation exposure in many clinical situations, particularly during radiotherapy for brain tumors. The critical role of the hippocampus in the pathogenesis of radiation-induced neurocognitive dysfunction is well recognized. The goal of this study is to test the potential contribution of non-targeted effects in the detrimental response of the hippocampus to irradiation and to elucidate the mechanisms involved. C57Bl/6 mice were whole body (WBI) or partial body (PBI) irradiated with 0.1 or 2.0 Gy of X-rays or sham irradiated. PBI consisted of the exposure of the lower third of the mouse body, whilst the upper two thirds were shielded. Hippocampi were collected 15 days or 6 months post-irradiation and a multi-omics approach was adopted to assess the molecular changes in non-coding RNAs, proteins and metabolic levels, as well as histological changes in the rate of hippocampal neurogenesis. Notably, at 2.0 Gy the pattern of early molecular and histopathological changes induced in the hippocampus at 15 days following PBI were similar in quality and quantity to the effects induced by WBI, thus providing a proof of principle of the existence of out-of-target radiation response in the hippocampus of conventional mice. We detected major alterations in DAG/IP3 and TGF-β signaling pathways as well as in the expression of proteins involved in the regulation of long-term neuronal synaptic plasticity and synapse organization, coupled with defects in neural stem cells self-renewal in the hippocampal dentate gyrus. However, compared to the persistence of the WBI effects, most of the PBI effects were only transient and tended to decrease at 6 months post-irradiation, indicating important mechanistic difference. On the contrary, at low dose we identified a progressive accumulation of molecular defects that tended to manifest at later post-irradiation times. These data, indicating that both targeted and non-targeted radiation effects might contribute to the pathogenesis of hippocampal radiation-damage, have general implications for human health.     

Radiation-Induced Senescence Reprograms Secretory and Metabolic Pathways in Colon Cancer HCT-116 Cells

Understanding the global metabolic changes during the senescence of tumor cells can have implications for developing effective anti-cancer treatment strategies. Ionizing radiation (IR) was used to induce senescence in a human colon cancer cell line HCT-116 to examine secretome and metabolome profiles. Control proliferating and senescent cancer cells (SCC) exhibited distinct morphological differences and expression of senescent markers. Enhanced secretion of pro-inflammatory chemokines and IL-1, anti-inflammatory IL-27, and TGF-β1 was observed in SCC. Significantly reduced levels of VEGF-A indicated anti-angiogenic activities of SCC. Elevated levels of tissue inhibitors of matrix metalloproteinases from SCC support the maintenance of the extracellular matrix. Adenylate and guanylate energy charge levels and redox components NAD and NADP and glutathione were maintained at near optimal levels indicating the viability of SCC. Significant accumulation of pyruvate, lactate, and suppression of the TCA cycle in SCC indicated aerobic glycolysis as the predominant energy source for SCC. Levels of several key amino acids decreased significantly, suggesting augmented utilization for protein synthesis and for use as intermediates for energy metabolism in SCC. These observations may provide a better understanding of cellular senescence basic mechanisms in tumor tissues and provide opportunities to improve cancer treatment.     

红外隐身涂层材料及技术研究进展

随着红外探测技术的不断进步, 以红外辐射为信号源的武器装备（红外夜视仪、 红外制导导弹等） 的识别、 探测和追踪能力越来越强, 使战斗机、 车辆和坦克等武器装备极易受到攻击甚至摧毁。 为了应对这些红外威胁, 提高武器装备在战场上的生存能力, 多种技术手段被研发和应用, 其中红外隐身涂层发挥着越来越重要的作用。 本文将简单介绍红外隐身涂层的工作原理, 从涂层材料和制备技术两个方面综述目前红外隐身涂层的研究进展, 并对其未来研究发展方向提出展望。     

空间高能质子对飞行器材料的损伤分析

针对高能粒子在空间环境中的辐射,本文简要介绍了空间高能质子在空间环境中的分布情况及在物质中的传输问题,评述了国外有关高能质子的非电离能损失及线性能量转移研究,并在此基础上重点分析和研究了高能质子对航空、航天材料的辐射损伤.从空间高能质子对材料的辐射损伤的角度,分析讨论了材料厚度与屏蔽效果的关系并提出了一些相关性的结论和展望;能量为10MeV～80MeV的质子最可能发生辐射损伤效应,质子拟合公式适合于入射质子能量较小的情况.     

Ce^3＋,Sb^3＋共激活的亚超细磷光体的微波快速合成和发光特性

首次采用微波辐射法快速合成了亚超细CaS:C^3 ,Sb^3 高效绿光磷光体，发现Ce^3 与Sb^3 离子之间存在着能量传,租是属于多极子相互作用的共振传递，因而Ce^3 对CaS:Sb^3 的发光有明显的敏化和增强。微波场作用下合成的双掺磷光体的激发峰与发射峰值分别恒定在259nm 和523nm处，并没有像传统高温固相合成法那样，随掺杂离子浓度的增大而发生红移现象。SEM照片显示，采用含不同一价阳离子（Na^ ,K^ ,NH4^ )无机盐作助熔剂制得的亚超细CaS:Ce^3 ,Sb^3 磷光体平均粒径为300nm-500nm，但其晶体形貌分别为立方形、球形和团聚状的雪花形，其中球形磷光体荧光最强。