Applications of atmospheric pressure plasma in microbial inactivation and cancer therapy: a brief review

Atmospheric pressure cold plasma, with advantages such as high particle activity, no thermal damage, high efficiency and direct and friendly contact with human tissues, is considered to have great potential in biomedical applications. Therefore, ‘plasma medicine’ as a new interdiscipline has been developed in the past two decades. This review first briefly describes the development of typical plasma sources suitable for biomedical applications, and those with different discharge forms are simply compared, evaluated and summarized. Subsequently, measurement of the crucial gaseous reactive particles (e.g. OH and O) and their spatio-temporal distributions are introduced. Meanwhile, the generation and variation rules and the related critical macroscopic parameters of the plasma-induced aqueous reactive species are summarized. Finally, related studies in the last ten years on the mechanisms of the plasma-driven microbial inactivation and plasma-induced apoptosis of cancer cells are introduced. Moreover, some scientific problems that need to be urgently solved in the field of plasma medicine are also discussed. This review will provide useful guidance for future related research.     

浅析建筑安全与危险之间的相互关系

浅析安全与危险之间相互联系、相互对立的关系及如何正确认识它们之间的辩证关系。文中简述生产经营活动中安全与危险之间的相互转换,着重阐述建筑施工中它们之间的联系,涉及建筑行业的安全管理问题、矛盾与解决方法,建筑安全管理及安全生产活动对于企业、社会及生活的影响。     

“十”字型钢骨柱的制作工艺

"十"字型钢柱广泛应用于型钢混凝土组合结构,这种结构有很多优点,可减小构件截面,增加使用空间,应用于高层建筑中可提高经济效益。北京朝阳世纪花园工程所有钢结构均为"十"字型钢骨柱,是应用"十"字型钢骨柱较典型的工程,论文以此工程为例,介绍了"十"字型钢骨柱的制作工艺。     

3-甲基-4-芳基-5-(2-吡啶基)-1,2,4-三唑的合成和表征

1,2．4-三唑类化合物与一些金属离子形成的配合物具有自旋转换作用。为了制备具有自旋转换功能的化合物,本文设计合成3-甲基-4-取代-5-(2-吡啶基)-1,2,4-三唑配体．报道了3-甲基-4-苯基-5-(2-吡啶基)-1,2,4-三唑和3-甲基-4-对甲氧苯基-5-(2-吡啶基)-1,2,4-三唑的合成,化合物的结构经IR、MS、^1H NMR确证。     

Degradation and mineralization of ciprofloxacin by gas–liquid discharge non-thermal plasma

A typical quinolones antibiotic ciprofloxacin(CIP) in aqueous solution was degraded by a gas–liquid discharge non-thermal plasma system. The discharge plasma power and the emission intensity of the excited reactive species(RS) generated in the gas phase were detected by the oscilloscope and the optical emission spectroscopy. The effects of various parameters on CIP degradation, i.e. input powers, initial concentrations addition of radical scavengers and p H values were investigated. With the increase of discharge power, the degradation efficiency increased but the energy efficiency significantly reduced. The degradation efficiency also reduced under high concentration of initial CIP conditions due to the competitive reactions between the plasma-induced RS with the degradation intermediates of CIP. Different radical scavengers(isopropanol and CCl_4) on ·OH and H· were added into the reaction system and the oxidation effects of ·OH radicals have been proved with high degradation capacity on CIP.Moreover, the long-term degradation effect on CIP in the plasma-treated aqueous solution proved that the long-lived RS(H_2O_2 and O_3, etc) might play key roles on the stay effect through multiple aqueous reactions leading to production of ·OH. The degradation intermediates were determined by the method of electrospray ionization(+)-mass spectroscopy, and the possible degradation mechanism were presented.     

特高频通信在大坝及堤防安全监测系统的应用

叙述了特高频通信 (VHF/UHF)技术在 DAMS- 型大坝及堤防安全监测自动化系统中的应用 ,重点对特高频通信网络组成、工作体制、性能指标、防雷措施做了简介 ,最后写了 DAMS- 型特高频数据采集系统在飞来峡水利枢纽社岗防护堤安全监测自动化工程中的应用     

Control of multidrug-resistant planktonic Acinetobacter baumannii: biocidal efficacy study by atmospheric-pressure air plasma

In this research,an atmospheric-pressure air plasma is used to inactivate the multidrug-resistant Acinetobacter baumannii in liquid.The efficacy of the air plasma on bacterial deactivation and the cytobiological variations after the plasma treatment are investigated.According to colony forming units,nearly all the bacteria (6-log) are inactivated after 10 min of air plasma treatment.However,7％ of the bacteria enter a viable but non-culturable state detected by the resazurin based assay during the same period of plasma exposure.Meanwhile,86％ of the bacteria lose their membrane integrity in the light of SYTO 9/PI staining assay.The morphological changes in the cells are examined by scanning electron microscopy and bacteria with morphological changes are rare after plasma exposure in the liquid.The concentrations of the long-living RS,such as H2O2,NO3,and O3,in liquid induced by plasma treatment are measured,and they increase with plasma treatment time.The changes of the intracellular ROS may be related to cell death,which may be attributed to oxidative stress and other damage effects induced by RS plasma generated in liquid.The rapid and effective bacteria inactivation may stem from the RS in the liquid generated by plasma and air plasmas may become a valuable therapy in the treatment of infected wounds.     

浅谈大型商场型钢混凝土钢骨梁安装技术

目前,在大型综合体公共建筑工程中,由于受空间要求限制,很多工程设计采用型钢混凝土组合结构,型钢混凝土组合结构的施工较为复杂。论文通过河源市商业中心购物MALL工程的施工实例,简要介绍型钢混凝土钢骨梁组合结构在施工过程中钢梁的安装,详细介绍了施工部署、吊车的选择等施工要点、注意事项等方面,为类似工程提供借鉴经验。     

Plasma-induced Styrene Grafting onto the Surface of Polytetrafluoroethylene Powder for Proton Exchange Membrane Application

Low-temperature plasma treatment was adopted to graft styrene onto polytetrafluo- roethylene （PTFE） powder, which is widely used in the fabrication of proton ex...     

远程氩气等离子体引发接枝丙烯酸改性聚丙烯微孔膜的研究

采用远程氩气等离子体对聚丙烯(PP)微孔膜进行表面亲水处理,并引发接枝丙烯酸单体实现永久亲水改性.研究了放电参数及样品位置对于亲水性及接枝率的影响,并运用扫描电镜(SEM)、红外光谱(FTIR)和光电子能谱(XPS)对等离子体处理后的微孔膜进行了表面分析.实验结果显示等离子体功率对处理后的微孔膜的表面亲水性和接枝率有较大影响:在低功率时,放电中心位置的微孔膜经等离子体处理后亲水性最好,同时该位置的接枝率也相应最大;而在高功率时,则是距放电中心20cm位置的微孔膜的亲水性和接枝率优于其他位置.＃红外光谱显示在低功率时膜表面有羧基生成,而在高功率时则仅生成醛基酮基羰基.对于高功率等离子体处理后的PP微孔膜,SEM结果显示在放电中心位置的膜表面有丝状胶合现象发生,XPS结果显示在距放电中心20cm位置处的膜表面含氧量增加最多.