基于μC/OS-III的喷雾结冰控制系统的设计

结冰是影响飞机安全飞行的重要因素,在某一型号飞机投入使用前,需要对该飞机除/防冰系统的性能进行验证。因此,研制了一套基于μC/OS-III的机载喷雾结冰控制系统;给出了系统的整体结构框架及其组成,重点介绍了该控制系统的硬件及软件的设计思路;系统实现了对喷雾设备的水、气路温度及压力的自动调节,在此基础上,还具有参数监测与显示、系统报警、数据分析与保存等功能。试验结果表明,该控制系统具有运行稳定、实时性好、调节速度快、控制精度高等特点,可以使用该系统进行喷雾结冰试验来考察某机型除/防冰系统的工作性能。     

Thermoelastic Stress Field Investigation of GaN Material for Laser Lift-off Technique based on Finite Element Method

The transient thermoelastic stress fields of GaN films is analyzed by the finite element method for the laser lift-off （LLO） technique. Stress distributions in GaN films irradiated by pulse laser with different energy densities as functions of time and depth are simulated. The results show that the high thermoelastic stress distributions in GaN films localize within about 1 μm below the GaN/Al2O3 interface using proper laser parameters. It is also found that GaN films can avoid the thermal deformation because the maximum thermoelastic stress 4.28 GPa is much smaller than the yield strength of GaN 15GPa. The effects of laser beam dimension and the thickness of GaN films on stress distribution are also analyzed. The variation range of laser beam dimension as a function of the thickness of GaN films is simulated to keep the GaN films free of thermal deformation. LLO experiments are also carried out. GaN-based light-emitting diodes （LEDs） are separated from sapphire substrates using the parameters obtained from the simulation. Compared with devices before LLO, P-I-V measurements of GaN- based LEDs after LLO show that the electrical and optical characteristics improve greatly, indicating that no stress damage is brought to GaN films using proper parameters obtained by calculation during LLO.     

α粒子辐照诱导拟南芥菜早期远程表观遗传改变研究

由于低能离子较低的组织穿透能力, 其诱变机理一直是研究者争论的问题。 近年来, 本研究组的一系列研究工作已经证明在植物中存在辐射远程（诱变）效应, 从一个新的角度解释了低能离子的诱变机理, 然而依然无法解释低能离子辐照中的许多独特生物现象, 而这些现象均具有明显的表观遗传学特性。 以表观遗传学最具标志性特征的胞嘧啶甲基化为研究对象, 以α粒子 拟南芥菜根辐照实验体系作为研究平台, 检测了远程组织(器官)甲基化相关基因 AtDML3 的表达及特定基因片段的甲基化水平。 研究证实, 在植物个体水平辐射可以诱导远程表观遗传的变化, 为进一步探索低能离子的诱变机理提供了新的思路。 Along the way, the mutagenic mechanism of low energy ions irradiation is a debatable issue. Recently, the existence of radiation induced long range (mutagenic) effects in vivo in plants has been performed in a series of studies of our group, which account for the mutagenesis of low energy ions irradiation in a new perspective. However, numerous distinct biology phenomena remain to be addressed, which bear obvious characteristics to epigenetic. In the present study, using the expression of methylation related AtDML3 gene and methylation level of specific gene segments as end points, the methylation of cytosine, the most important feature of epigenetic, was investigated. It was shown that, in A. thaliana, root loca lized α irradiation could induce epigenetic changes in aerial parts which avoided the direct irradiation. The radiation induced long range epigenetic changes were confirmed in this study, which supplied innovative ideas for the further investigation of the mutagenetic mechanism of low energy ions irradiation.     

以SDS-PVP项链状软团簇为模板简易一锅法合成Cu2O中空亚微球

在SDS-PVP水溶液中采用N2H4•H2O还原CuSO4, 在pH (10±0.5), (40±1.0) ℃条件下反应55 min得到橙色Cu2O溶胶, 离心分离产物经XRD鉴定为Cu2O立方晶系晶体; SEM和TEM表明该法获得的晶体为形状规整、粒径分布窄的Cu2O中空亚微球, 并证实系由大量10 nm量级的原级Cu2O纳米晶粒组装而成. 根据实验事实推断, SDS-PVP项链状软团簇提供了“双重软模板”功能, 借助独特的“模板诱导两级组装”作用一锅法合成了Cu2O中空亚微球. Cu2O中空亚微球生长的可能途径为: 首先, 项链状软团簇中的SDS束缚胶束作为第一重软模板, 诱导一级组装10 nm量级的原级Cu2O纳米晶粒; 然后, 软团簇中立体桥联SDS束缚胶束的PVP链节作为第二重软模板, 诱导一定空间范围内的原级Cu2O纳米晶粒长大并进一步聚集/二级组装, 经一锅法合成得到次级Cu2O中空亚微球. 实验结果证明该一锅法温和、简便、快捷, Cu2O中空亚微球的粒径分布窄.     

银镜反应实验条件优化的研究性学习活动及行为分析

选择银镜反应实验优化条件为研究性学习活动,阐述了活动目标、实施步骤、银镜反应的正交设计、实验过程及结论。利用NVivo 10.0质性分析工具,对上述活动进行质性分析,阐述了研究过程以及利用NVivo 10.0质性分析工具获得的结论。     

碳离子辐射诱导秀丽隐杆线虫生殖细胞凋亡研究

重离子辐射具有独特的深度剂量分布和较高的相对生物学效应,被认为是理想的放疗手段。重离子的生物学效应在径迹形成过程中由多个物理参量共同决定,而这些物理参量和离子入射深度紧密相关,因此明确离子不同入射深度的生物学效应对重离子肿瘤放疗方案的设计和优化有着重要的理论和应用价值。使用兰州重离子研究装置HIRFL-CSRe 终端的碳离子束作为辐射源,以活体模式动物线虫作为实验对象,以线虫生殖细胞的凋亡水平作为生物学检测终点,研究了10 和20 Gy 碳离子辐射在辐射的入口、坪区和峰区的当代生物学效应和对后代个体基因组不稳定性的影响。结果表明:10 和20 Gy 碳离子辐射在三个不同的辐照区域内均显著增加了辐射当代的线虫生殖腺细胞的凋亡水平,并表现出一定的辐射区域和辐射剂量依赖性。同时,辐射诱导的后代个体基因组不稳定性也表现出一定的辐射区域和辐射剂量相关性。Heavy ion irradiation is a perfect means in radio-therapy due to its special depth dose distribution and high relative biological effects. The biological effects of heavy ion irradiation are determined by some major physical parameters, and vary along the tracks of heavy ions. Therefore, it is very significant for the tumor radio-therapy to investigate the biological effects along whole range of heavy ion radiation. In the present study, Caenorhabditis elegans, a model in vivo, was irradiated by carbon ion beams from HCRFL-CSRe, The level of germ cell apoptosis of worms was used as a checking endpoint for DNA damage, the effects of carbon irradiation located in the entrance, plateau and peak regions on the genomic instability of the irradiated worm and their progeny were detected. The results showed that the 10 and 20 Gy of carbon ion radiations led to the increased germ cell apoptosis in irradiated worms and these effects depend on the worm location along the range of carbon ions and the irradiation dosage. The results also suggested that heavy ion irradiation induced the up-regulated genomic instability in their progeny, and might be related to both the irradiation dose and the irradiated location.     

便携式食品直链和支链淀粉速测仪的研制

依据等吸收双波长消去比色法原理,研制了便携式食品直链和支链淀粉速测仪,并进行两种淀粉含量的检测.验证试验结果表明线性关系(R2 0.999)、精密度(RSD%0. 7%)、稳定性(RSD%1. 5%)、重复性(RSD%2.0%)、重现性(实验室内RSD%2.5%,实验室间RSD%4.2%)、回收率(平均回收率高于90%,RSD%2.5%)和系统适用性(设备RSD%2.0%,设备之间RSD%3.5%)良好.其检测过程简单、快速、准确,两种淀粉的检测和参比波长集成在仪器装置单片机系统中,试验时可直接使用,无需再次对其进行设定.两种淀粉的吸光度差值ΔA直和ΔA支只需测定两次,节省了操作时间,提高了样品的检测效率.便携式速测仪的研制为快速、准确地检测大批量样品中两种淀粉提供了有力的技术保障.     

Fe/Co/Ni-N共掺杂石墨烯氧还原反应活性的DFT研究

为了研究Fe/Co/Ni-N掺杂石墨烯的氧还原反应(ORR)活性,比较单金属原子和氮不同的掺杂方式对石墨烯ORR活性的影响.利用Materials Studio软件建立了Fe/Co/Ni-N掺杂石墨烯模型,然后将氧气分子分别吸附在Fe/Co/Ni-N掺杂石墨烯模型表面上.采用CASTEP模块对构建的模型进行结构优化并模拟计算,分析了Fe/Co/Ni-N掺杂石墨烯的吸附能、脱附能和导电性变化规律.基于模拟计算,发现单金属原子掺杂石墨烯时,Fe掺杂石墨烯的ORR活性优于Co和Ni;单金属原子和氮共掺杂石墨烯时,Fe-N掺杂石墨烯的ORR活性高于Co-N和Ni-N掺杂石墨烯,且M-N₄-G形态的ORR活性优于M-N₁-G、M-N₂-G和M-N₃-G.     

对高中生化学学习中组织策略运用的调查研究

采用自编问卷,对江苏省南部地区四星级高中1000多名高中生进行了化学学习中运用组织策略现状的调查。结果表明,学生在学习新知识和解决问题时运用组织策略的状况较好,在复习时运用组织策略的状况不容乐观;学生较多运用归类法和列提纲的组织策略,较少运用列表格和图解法来组织知识。提出了提高学生组织策略水平的教学建议。     

部分多值逻辑中保正规关系的准完备集的性质

在多值逻辑完备性理论中,Sheffer函数的刻划是一个重要的问题,此问题的解决可归结为定出其准完备集的最小覆盖.本文对部分多值逻辑函数集中保正规关系的准完备集的性质进行了研究,为确定部分多值逻辑函数集中准完备集的最小覆盖奠定了一定的基础.