Damage to Alexandrlum tamarense DNA Caused by Hydroxyl Radicals

利用羟基自由基(·OH)压载水处理系统,采用大气压强电场放电技术制取·OH溶液对塔玛亚历山大藻(Alexandrlum tamarense)进行处理。通过普通光学显微镜,荧光显微镜和电子显微镜对·OH处理前后的塔玛亚历山大藻的细胞结构进行观测。结果表明,·OH能有效破坏藻细胞,从而造成藻类死亡。利用随机扩增多态性DNA(random amplification polymorphic DNA,RAPD)和实时定量PCR(RT-PCR)相结合的技术检测·OH对DNA链的破坏作用。共得到了3条有显著差异的扩增产物。这3条扩增产物经测序,并通过NCBI(national center of biotechnology information)的比对分析,最终得到1条可用RT-PCR检测·OH对DNA破坏作用的基因序列。以上的结果表明,·OH压载水处理系统能有效去除塔玛亚历山大藻,并对其DNA造成破坏。This paper referred to a ballast water treatment system by using hydroxyl radical(·OH),in which the atmospheric pressure electric discharge technology was applied to produce hydroxyl radicals to treat Alexandrlum tamarense.The morphology of A.tamarense before and after being treated by ·OH was observed by ordinary optical microscope,fluorescence microscope and electron microscope,respectively.The findings presented that ·OH effectively did damage to the algal cells and led to algae perishing and the damage of ·OH to DNA strand was detected by using combination of random amplified polymorphic DNA(RAPD)and RT-PCR technology.In addition,three DNA bands with differences were found and sequenced;then sequence alignment was performed in the website of National Center of Biotechnology Information(NCBI).Finally,a gene sequence was found for RT-PCR analysis that further proved the damage to DNA strand.In conclusion,the ballast water treatment system of ·OH was capable to removes A.tamarense in water effectively,causing damages of the DNA strand.中国杰出青年学者基金(NSFC)(61025001);; 中国国家科技支撑项目(2013BAC06B00);; 海洋科学研究公共利益的专项基

Application of Hydroxyl Radicals Ballast Water Treatment System on Ship

构建了250 m~3/h羟基自由基压载水处理系统并进行了实船试验。整个试验按照国际海事组织(IMO)的要求进行,对水中藻类、细菌和水质参数进行了检测。试验结果显示,经此系统处理后压载水中藻类浓度和细菌浓度达到了IMO规定的压载水排放标准;处理后的压载水水质变好,不会造成二次污染。该系统可实现在压载水的输送过程中杀灭外来水生生物和病原体,并可以改善水质。A 250 m3/h hydroxyl radicals ballast water treatment system is constructed and tested on ship. The whole experiment is conducted in accordance with the requirements of International Maritime Organization(IMO). The concentration of algae and bacteria, as well as some water quality parameters are determined. Experimental results show that the concentration of algae and bacteria in ballast water treated by this system achieved the ballast water discharge standard of IMO regulations. The treated ballast water has higher water quality and will not cause secondary pollution. The system can kill the alien aquatic organisms and pathogens in the process of delivering ballast water and can improve water quality

Treatment System of Ballast Water in Oceanic Ships Using Hydroxyl Radical(·OH) Based on Strong Electric-field Discharge

船舶压载水的交换可能致使海洋中不同海域生物的交互入侵,打破原有海域生态系统的平衡,为此,研究了一种基于强电离放电方法规模化制备羟基自由基技术的新型船舶压载水处理系统。该系统利用大气压下强电场电离放电,将氧气和气态水充分电离,离解产生大量氧活性粒子,并通过高速射流,在管路中完成空化效应,制备高浓度羟基溶液,实现在船舶压载水装载过程中快速、高效的杀灭有害微生物和病原体。实验结果显示,压载水经过质量流量为10 T/H的压载水处理系统处理后,藻和细菌被全部杀灭,致死率达100%。在48 H和120 H两个时间点对处理舱进行检测,未发现有再生现象发生。除此之外,比较处理前后水质参数及生物学指标变化情况,经羟基处理后丙二醛(MdA)浓度有明显升高,而水中bOd、COd质量浓度明显降低。通过对MdA检测,羟基杀灭机制很可能是通过影响细胞脂质过氧化进程来完成。处理后压载水的水质得到了明显改善,减轻了压载水排放过程中对排放水域的环境压力。Exchanging ballast water from ships might cause the interactive bio-invasion of different seawater, and break ecological balance.Therefore, we described a ship ballast water system which generates hydroxyl radical from strong electric field ionization discharge.The discharge at atmospheric pressure could ionize O2 in air and gaseous H2O to form a large amount of oxygen active particles, which were injected into a tube of the ballast water treatment system to generate a high concentration of ?OH solution through the cavitation effect.The ?OH solution could kill harmful micro-organisms in ballast water quickly and efficiently.Test results showed that, after being treated by the system at a flow speed of 10 t/h, the single-cell algae and bacteria in ballast water were almost completely eliminated, and the micro-organisms did not reactivate at 48 h and 120 h.In the treated ballast water, the concentration of malondialdehyde(MDA) obviously increased while BOD and COD decreased significantly.According to the MDA test, ?OH probably kills algae and bacteria though preoxidating their cytolipin.The treatment can effectively lower the pollution from the ballast water.The results indicate that solution of high ?OH concentration significantly improves the quality of ballast water, hence it relieves the environmental threats of the ballast water discharge on local marine system.国家高技术研究发展计划(863计划)(2012AA062609); 国际科技合作项目(2010DFA61470); 国家杰出青年科学基金(61025001)~

Study on the corrosion effect of ballast tank caused by ballast water treatment of hydroxyl radical

针对羟基自由基(·OH)法处理船舶压载水过程中可能对压载舱造成腐蚀情况进行研究。在最大羟基处理浓度2.5 Mg/l条件下作用压载舱常用低碳钢、不锈钢及非金属材料,检测处理前后压舱水对压载舱材料的腐蚀影响。结果表明羟基法处理压载水系统在高效杀灭外来有害生物的过程中,对压载舱金属与非金属并不具有明显的腐蚀增强,这一结果满足IMO的技术要求。羟基法在快速处理船舶压载水的同时对于压载舱壁金属腐蚀而言是安全的。该研究结果对日后压载舱的防腐设计以及压载水处理装置在船舶上的推广应用具有重要的意义。The thesis presents the study of the situation that hydroxyl radical( ·OH) may cause the corrosion of ballast tank material in the process of ballast water treatment.Under the highest using concentration of hydroxyl radical,the materials,such as low-carbon steel,stainless steel,and Non-metallic,are commonly used in the ballast tank to evaluate the corrosion influence that ballast water makes on the materials of ballast tank in the pre-and post-treatment testing.The result showed that the corrosion effect of the hydroxyl radical on the metal and non-metal materials does not increase obviously when used in the system of ballast water treatment to effectively kill the exotic pests,which meets the requirements of IMO.It is safe for ballast tank wall metal to utilize the hydroxyl radical in the ballast water treatment.The study result holds a great significance for the anti-corrosion design of the ballast tank and the popularization as well as the application of this ballast water treatment system on board.国家高技术研究发展计划(2012AA062609); 国家杰出青年科学基金资助项目(61025001

Hybrid Force/Position Control of Aerial Manipulators in Contact Operation

针对飞行机械臂系统移动接触作业问题,使用了一个力/位置混合控制框架,用以控制飞行器系统持续可靠地接触外部环境同时保持一定大小的接触力,并实现在接触过程中的期望轨迹跟踪.首先将作业空间分成2个子空间&mdash;&mdash;约束空间和自由空间,并分别进行力控制和位置控制.对于力控制问题,证明闭环无人机系统是一个类弹簧-质量-阻尼系统,然后在约束子空间中设计逆动力学控制器来实现接触力控制.自由飞行空间中的运动控制依靠轨迹规划和位置控制器来实现.最后,开发了基于六旋翼飞行机器人的单自由度飞行机械臂系统,在飞行状态下进行接触墙面并跟踪倾斜直线轨迹的实验.结果显示本文所使用方法能够保证在平稳移动的同时控制期望的接触力.</p

Research on biological effectiveness of hydroxyl radicals killing marine red tide algae in ballast water

本研究采用大气压下强电离放电协同气液混溶技术,高效制备羟基自由基(·OH)杀灭3个门的典型有害赤潮物种,使用荧光染色、测定光合作用潜能等生物学检测方法确定·OH致死阈值。结果表明,5.05×10~4 cells/mL的赤潮异弯藻(Heterosigma akashiwo)、5.28×10~4 cells/mL的亚历山大藻(Alexandrium tamarense)和5.02×10~4 cells/mL的中肋骨条藻(Skeletonema costatum),其致死阈值分别为1.24mg/L、2.01mg/L、1.12mg/L,此时其叶绿素a分解率分别为77%、85%和74%。利用光学显微镜观察,处理前后藻细胞结构有明显的改变。因此,·OH致死方法可有效地杀灭压载水中的有害赤潮藻。In this study,the three typical red tide species were chosen as the experiment algae and the inactivation was achieved by hydroxyl radials generated from a strong ionization discharge combined with hydrodynamic cavitations.The viability and integrity of the algae were determined by the fluorescence staining and Pulse Amplitude Modulation.The results suggest that a quick and complete loss of viability was achieved for three species after exposure to hydroxyl radical,for the Heterosigma akashiwo,Alexandrium tamarensem,Skelrtonema costatum which the density is 5.05×10~4 cells/mL,5.28×10~4 cells/mL,5.02×10~4 cells/mL respectively,the lethal thresholds are1.24mg/L,2.01mg/L,and 1.12mg/L separately.Meanwhile Algal cells were deformed and shrunk after·OH attack and chlorophyll content was degraded at the same time.The chlorophyll content decomposition rate reaches to 77%,85%and 74%at the lethal thresholds.Above all,the use of hydroxyl radicals is an efficient method to kill red tide species in ballast water.国家科技支撑计划(2013BAC06B01,2013BAC06B02);; 国家重大科研仪器研制项目(NSFC 61427804);; 国家杰出青年科学基金(NSFC61025001);; 海洋科学研究公共利益的专项基

Analysis of Risk Factors of Depressive Symptoms in Burn Patients

目的 探索烧伤患者抑郁症状的相关危险因素。方法 选取2019年4月至2020年1月安徽医科大学第一附属医院收治的206例烧伤患者作为研究对象，收集患者性别、年龄、婚姻状况、文化程度、体重指数、烧伤严重程度、烧伤面积以及汉密尔顿抑郁量表（HAMD）、汉密尔顿焦虑量表（HAMA）、急性应激障碍量表（ASDS）、失眠严重程度指数量表（ISI）评分，Logistic回归分析烧伤患者伴发抑郁症状的危险因素，Spearman相关性分析各因素与烧伤患者伴发抑郁症状的相关性。结果 206例烧伤患者共收集有效问卷194份（94.17%）, 194例患者中伴发抑郁症状者111例（57.22%），设为抑郁组；未伴发抑郁症状者83例（42.78%），设为非抑郁组。Logistic回归分析结果显示，HAMA、 ASDS高评分是烧伤患者伴发抑郁症状的独立危险因素（95%CI为1.170～1.573、 1.000～1.080,P</p

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel