Effect of irradiation and packaging type on sensory quality of chill-stored turkey breast fillets

A panel of experienced assessors was used to test the effect of irradiation at 2.5kGy (250krad) on the sensory quality of 1-day and 21-day-old turkey breast fillets stored at 1°C in either oxygen-permeable polythene or an oxygen-impermeable barrier film. In the application of Free Choice Profiling and Generalized Procrustes Analysis, assessors used their own terms to describe the appearance, odour and flavour of the samples.
The irradiated samples showed negligible growth of micro-organisms across 21 days of storage. Radiation treatment resulted in an intense pink colour in the raw and cooked samples, which was maintained during storage in oxygen-impermeable film, but decreased in samples exposed to oxygen during storage. Radiation also produced a set of unpleasant raw odour notes variously described as sour, rancid, mature, bad meat or putrid in the samples stored in oxygen-impermeable film. These notes were unlike the sulphurous notes previously associated with protein denaturation in irradiated chicken and were apparently distinct from the odour notes that developed in corresponding non-irradiated samples.     

Radiation effects on insulators for superconducting fusion magnets

Fibre-reinforced plastics (FRPs) are candidate materials for the insulation of superconducting magnet coils in future fusion reactors. This paper reports on a test programme performed to assess the mechanical properties of these materials and to obtain information on the damage and fracture mechanisms. Different types of FRPs (epoxies and poly- and bismaleimides as resins; two- and three-dimensional E-, S- or T-glass fabrics as reinforcements) were irradiated at room temperature by 2 MeV electrons and ⁶⁰Co-gamma rays up to 1.8 × 10⁸ Gy and by different reactor spectra up to a neutron fluence of 1 × 10²³ m⁻² (E > 0.1 MeV) at room temperature, 80 K or 5 K. Mechanical tests in tension as well as in the intralaminar crack opening and shear mode were carried out on the irradiated samples at 77 K. After low temperature irradiation, half of the samples were subjected to a warm-up cycle to room temperature before testing at 77 K. Results on the influence of different radiation sources and annealing cycles on the mechanical properties of these materials will be discussed.     

微波辐射对细胞膜通透性的影响

本实验通过电镜镧细胞化学方法，观察了微波辐射对生物样品细胞膜通透性的影响。在常规化学固定的情况下，镧颗粒沿细胞间隙密集分布而不能进入细胞内。生物样品经微波辐射后，在细胞内甚至在线粒体等细胞器内可观察到较多的镧颗粒。提示：微波辐射使生物膜的通透性发生了改变。     

轻/重水堆中子辐照氢区熔硅退火特性的比较

用电阻率测量、金相观察以及红外光谱等方法分别研究了氢区熔硅单晶在轻水反应堆和重水反应堆进行中子辐照后的退火特性。电阻率退火曲线表明，两种中子辐照样品都存在氢致施主。随着退火温度由低到高，轻水堆辐照样品存在一个导电类型由ｐ型到ｎ型的转型过程，而且在这种转型过程中，有一个明显的“周边滞后”现象。在重水堆辐照样品中，热处理缺陷表现为氢致Φ型缺陷（大麻坑），而在轻水堆辐照样品中，热处理缺陷表现为尺寸小得多的氢沉淀。红外光谱测量结果表明，重水堆中子辐照的样品经短时退火后观察不到氧沉淀，而在轻水堆辐照样品中存在吸收峰在１２３０ｃｍ－１附近的氧沉淀。     

放电故障紫外检测系统及其状态识别方法

紫外成像检测技术是一种检测高压设备故障的新方法;在此技术上研究设计了一种放电故障紫外检测系统,该系统能对实时采集的紫外图像进行相关的技术处理,同时可对故障点进行准确定位;根据数据建立了设备状态模型并提出一种基于人工神经网络的状态识别方法,应用MATLAB工具进行神经网络的设计和模拟,仿真结果达到预期效果;该系统可以准确地诊断设备的故障和运行状况,有较好运用前景和理论意义。     

衣康酸光固化树脂的研究进展

被誉为"绿色技术"的光固化技术,不仅节能环保而且经济高效,已在众多领域得以应用。利用天然可再生资源制备光固化树脂对光固化技术的可持续发展具有重要意义。衣康酸作为一种来源广泛的天然可再生资源,其分子结构中同时含有不饱和双键和两个羧基,可替代丙烯酸、己二酸等石化资源合成各种光固化不饱和树脂,所得树脂综合性能优良。本文综述了衣康酸制备光固化树脂的研究进展,主要包括环氧衣康酸树脂、衣康酸聚酯、衣康酸聚酯丙烯酸酯、衣康酸聚氨酯丙烯酸酯等。由衣康酸合成的光固化树脂在涂料、生物医药和3D打印材料等领域具有重要的应用价值,为生物质资源的高值化利用提供了新途径。     

Elucidation of the Clustered Nano-Architecture of Radiation-Induced DNA Damage Sites and Surrounding Chromatin in Cancer Cells: A Single Molecule Localization Microscopy Approach

In cancer therapy, the application of (fractionated) harsh radiation treatment is state of the art for many types of tumors. However, ionizing radiation is a “double-edged sword”—it can kill the tumor but can also promote the selection of radioresistant tumor cell clones or even initiate carcinogenesis in the normal irradiated tissue. Individualized radiotherapy would reduce these risks and boost the treatment, but its development requires a deep understanding of DNA damage and repair processes and the corresponding control mechanisms. DNA double strand breaks (DSBs) and their repair play a critical role in the cellular response to radiation. In previous years, it has become apparent that, beyond genetic and epigenetic determinants, the structural aspects of damaged chromatin (i.e., not only of DSBs themselves but also of the whole damage-surrounding chromatin domains) form another layer of complex DSB regulation. In the present article, we summarize the application of super-resolution single molecule localization microscopy (SMLM) for investigations of these structural aspects with emphasis on the relationship between the nano-architecture of radiation-induced repair foci (IRIFs), represented here by γH2AX foci, and their chromatin environment. Using irradiated HeLa cell cultures as an example, we show repair-dependent rearrangements of damaged chromatin and analyze the architecture of γH2AX repair clusters according to topological similarities. Although HeLa cells are known to have highly aberrant genomes, the topological similarity of γH2AX was high, indicating a functional, presumptively genome type-independent relevance of structural aspects in DSB repair. Remarkably, nano-scaled chromatin rearrangements during repair depended both on the chromatin domain type and the treatment. Based on these results, we demonstrate how the nano-architecture and topology of IRIFs and chromatin can be determined, point to the methodological relevance of SMLM, and discuss the consequences of the observed phenomena for the DSB repair network regulation or, for instance, radiation treatment outcomes.     

核级FeCrAl包壳材料研究进展

摘要：日本福岛核电站泄漏事故暴露了锆合金易与水蒸气反应造成爆炸的缺陷,又将人们的视线拉回了各项性能较为均衡的FeCrAl合金。FeCrAl合金较锆合金具有更好的耐腐蚀性能,更能满足核反应堆高温水蒸气环境下的工作条件。为进一步保障核反应堆安全性,各国学者对FeCrAl合金的性能进行了大量研究。基于此,综述了FeCrAl合金腐蚀机制及其在高温蒸汽和高温水环境中的腐蚀行为;探讨了合金元素（稀土、Ti、Zr、Nb和Mo）、变形和热处理对合金力学性能的影响;总结了FeCrAl合金辐照性能和焊接性能的研究进展。最后指出了核级FeCrAl合金在研究中存在的不足及未来重点发展方向,为今后其他学者在该领域的研究提供参考。     

Fluorescent lamp promoted formaldehyde removal over CeO2 catalysts at ambient temperature

Exploring an alternative strategy with high efficiency and low cost to abate formaldehyde (HCHO) in indoor environment, is of increasing significance for people's health. CeO₂ catalysts prepared by hydrothermal, precipitation and calcination methods were investigated for HCHO removal at ambient temperature. It is found that indoor fluorescent light visibly boosts the catalytic performance of CeO₂ catalysts for HCHO decomposition at ambient temperature. Among the CeO₂ catalysts, CeO₂ prepared from hydrothermal method (CeO₂–H) exhibits a superior catalytic performance and an excellent durability by eight recycle times. Based on the characterization and analysis, the excellent catalytic performance of CeO₂–H is mainly contributed by its abundance of surface oxygen vacancies, and photogenerated electrons and hole activated by fluorescent light. This work shows a potential practicability in HCHO pollution elimination by taking full advantage of the existing lighting in indoor environments.     

Dose and dose rate effects on coherent-to-incoherent transition of precipitates upon irradiation

A typical precipitation hardened alloy, Cu-Co dilute alloy was selected to study the precipitation behavior and irradiation effect on precipitates. It is found that the principal effect of ion irradiation on the coherent precipitates is loss of coherency, and TEM cross-section observations show that the fraction of the incoherent precipitates is dependent on dose but not on dose rate during heavy ion irradiation.