atmospheric pressure plasma

大气压等离子体
  • 文章类型: Journal Article
    正交钙钛矿GdFeO3纳米结构是具有多铁性的有前途的材料。在这项研究中,通过固体金属前体的双阳极溶解开发了一种新的低温等离子体辅助方法,用于制备钙钛矿GdFeO3纳米颗粒(NPs),该纳米颗粒既可以作为胶体收集,也可以作为薄膜沉积在基材上。Gd和Fe的两个固体金属箔用作前体,增加了方法的简单性和可持续性。正交钙钛矿GdFeO3相的形成得到了高分辨率透射电子显微镜的支持,X射线衍射,X射线光电子能谱,和拉曼测量,虽然Gd的元素分布均匀,Fe,和O被能量色散X射线光谱证实,证明了三元化合物NP的成功制备。NPs的磁性能显示出反铁磁材料典型的零剩余磁化强度,以及在高磁场下的饱和,这可能是由Gd和Fe磁性亚晶格之间的自旋相互作用引起的。还讨论了这种新型等离子体辅助方法中三元化合物NP的形成机理。还对该方法进行了修改,以证明薄膜的直接一步沉积,为其在磁存储器件和气体传感器制造中的未来应用开辟了机会。
    Orthorhombic perovskite GdFeO3 nanostructures are promising materials with multiferroic properties. In this study, a new low-temperature plasma-assisted approach is developed via dual anodic dissolution of solid metallic precursors for the preparation of perovskite GdFeO3 nanoparticles (NPs) that can be collected both as colloids as well as deposited as a thin film on a substrate. Two solid metallic foils of Gd and Fe are used as precursors, adding to the simplicity and sustainability of the method. The formation of the orthorhombic perovskite GdFeO3 phase is supported by high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman measurements, while a uniform elemental distribution of Gd, Fe, and O is confirmed by energy dispersive X-ray spectroscopy, proving the successful preparation of ternary compound NPs. The magnetic properties of the NPs show zero remnant magnetization typical of antiferromagnetic materials, and saturation at high fields that can be caused by spin interaction between Gd and Fe magnetic sublattices. The formation mechanism of ternary compound NPs in this novel plasma-assisted method is also discussed. This method is also modified to demonstrate the direct one-step deposition of thin films, opening up opportunities for their future applications in the fabrication of magnetic memory devices and gas sensors.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    活性氧(ROS)/活性氮(RNS)在缺血性脑卒中的发生发展中具有“双重”效应。我们先前指出,基于ROS/RNS世代,大气压等离子体(APP)在体外显示出神经保护作用。然而,机制仍然未知。在这项工作中,SH-SY5Y细胞采用氧糖剥夺(OGD)损伤刺激缺血性脑卒中病理损伤过程。氦气APP用于SH-SY5Y细胞治疗,以优化参数评估APP预处理对OGD损伤的神经保护作用。在预处理过程中,APP显著提高了细胞外和细胞内ROS/RNS的产生。因此,APP预处理通过提高LC3-II/LC3-I比例和自噬体形成增加SH-SY5Y细胞自噬。同时,随着APP处理时间的延长,APP预处理减少了OGD引起的细胞凋亡,通过用自噬抑制剂3-甲基腺嘌呤(3-MA)预处理而废除。ROS清除剂N-乙酰-L-半胱氨酸(NAC)单独或与NO清除剂羧基-PTIO联合消除APP预处理诱导的SH-SY5Y自噬和细胞保护作用,而单独的NO清除剂没有。此外,我们观察到APP处理的SH-SY5Y细胞中AMP活化蛋白激酶(AMPK)的磷酸化升高和哺乳动物雷帕霉素靶蛋白(mTOR)的磷酸化降低。AMPK抑制剂化合物C(CC)减弱了这种作用,ROS清除剂NAC和自噬抑制剂3-MA。此外,在大脑中动脉闭塞(MCAO)模型大鼠中初步证实了APP的细胞保护作用。结果表明,在MCAO过程中,大鼠吸入APP可以改善神经功能,减少脑组织细胞凋亡,减少脑梗死体积。我们的数据表明,APP预处理产生的ROS在SH-SY5Y细胞通过激活自噬和ROS/AMPK/mTOR通路对OGD损伤的神经保护作用中起着至关重要的作用。
    Reactive oxygen species (ROS)/reactive nitrogen species (RNS) exert a \"double edged\" effect on the occurrence and development of ischemic stroke. We previously indicate that atmospheric pressure plasma (APP) shows a neuroprotective effect in vitro based on the ROS/RNS generations. However, the mechanism is still unknown. In this work, SH-SY5Y cells were treated with oxygen and glucose deprivation (OGD) injuries for stimulating the ischemic stroke pathological injury process. A helium APP was used for SH-SY5Y cell treatment for evaluating the neuroprotective impacts of APP preconditioning against OGD injuries with the optimized parameters. During the preconditioning, APP significantly raised the extracellular and intracellular ROS/RNS production. As a result, APP preconditioning increased SH-SY5Y cell autophagy by elevating LC3-II/LC3-I ratio and autophagosome formation. Meanwhile, APP preconditioning reduced cell apoptosis caused by OGD with the increased APP treatment time, which was abolished by pretreatment with autophagy inhibitor 3-methyladenine (3-MA). The ROS scavenger N-acetyl-L-cysteine (NAC) alone or combined with NO scavenger carboxy-PTIO abolished the APP preconditioning induced SH-SY5Y autophagy and the cytoprotection, whereas the NO scavenger alone did not. In addition, we observed the elevated phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphorylation of mammalian target of rapamycin (mTOR) in APP treated SH-SY5Y cells. This effect was attenuated by AMPK inhibitor Compound C (CC), the ROS scavenger NAC and autophagy inhibitor 3-MA. Furthermore, the cytoprotective effect of APP was preliminarily confirmed in the rats of middle cerebral artery occlusion (MCAO) model. Results showed that APP inhalation by rats during MCAO process could improve neurological functions, reduce cell apoptosis in brain tissues and decrease cerebral infarct volume. Our data suggested that ROS produced by APP preconditioning played a vital role in the neuroprotective effect of SH-SY5Y cells against OGD injuries by activating autophagy and ROS/AMPK/mTOR pathway.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    使用溶液方法处理的金属氧化物材料由于其在用于现代电子学中的薄膜晶体管(TFT)的各种衬底上有效且经济地产生透明绝缘层或有源沟道层的能力而获得显著关注。TFT的关键特性很大程度上取决于电荷载流子在半导体和电介质界面处的薄层附近的行为。有效地控制这些特性提供了增强器件性能的简单而有效的方法。在这项研究中,我们提出了一种利用大气压等离子体(APP)处理的新策略,以调节通过使用溶液方法处理的TFT中的电介质薄膜以及电介质和半导体层之间的界面的电性能。通过APP曝光,对于溶液处理的TFT,实现了关键TFT参数的显著改进。界面状态已从1013降低到1011cm-2,开/关电流比从103增加到106,同时保持了34cm2V-1s-1的高场效应迁移率。此外,紫外可见光谱和X射线分析证实了APP处理在控制界面状态和陷阱方面的有效性,导致TFT的整体性能增强。此外,我们的实验结果已使用制造TFT的计算机辅助设计(TCAD)模拟技术进行了系统验证。
    Metal oxide materials processed using solution methods have garnered significant attention due to their ability to efficiently and affordably create transparent insulating layers or active channel layers on various substrates for thin-film transistors (TFTs) used in modern electronics. The key properties of TFTs largely depend on how charge carriers behave near the thin layer at the semiconductor and dielectric interface. Effectively controlling these characteristics offers a straightforward yet effective approach to enhancing device performance. In this study, we propose a novel strategy utilizing atmospheric pressure plasma (APP) treatment to modulate the electrical properties of dielectric thin films and the interfaces between dielectric and semiconductor layers in TFTs processed by using solution methods. Through APP exposure, significant improvements in key TFT parameters were achieved for solution-processed TFTs. Interface states have been reduced from 1013 to 1011 cm-2, and the on/off current ratio has increased from 103 to 106 while maintaining a high field-effect mobility of 34 cm2 V-1 s-1. Additionally, UV-visible spectroscopy and X-ray analysis have confirmed the effectiveness of APP treatment in controlling interface states and traps, leading to overall performance enhancements in the TFTs. Furthermore, our experimental findings have been systematically validated using technology computer-aided design (TCAD) simulations of fabricated TFTs.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    Z夹装置是惯性约束聚变的关键部件,其中不锈钢电极必须承受高达MA/cm2的高电流密度。附着在电极表面的气体和难以去除的杂质会电离,显著影响器件的导电效率。在本文中,在大气压下使用大面积等离子体射流对不锈钢电极的表面进行清洁。润湿性,化学成分,使用水接触角测量仪和X射线光电子能谱(XPS)表征电极表面的化学状态。系统分析了不同排放参数下的清洗效果。结果表明,不锈钢电极表面的碳污染物含量显着降低,等离子清洗后从62.95%下降到最低37.68%。此外,水接触角从70.76°下降到最小29.31°,表面吸附的水分子含量从17.31%下降到最低5.9%。基于不锈钢焊条表面微量元素含量和化学状态的演化过程,利用不锈钢表面污染物的分层清洗模型,分析了大气压等离子体对表面粘附物质的清洗过程。
    The Z-pinch device is a critical component in inertial confinement fusion, where stainless steel electrodes must withstand high current densities of up to MA/cm2. Gases and difficult-to-remove impurities adhering to the electrode surfaces can ionize, significantly impacting the device\'s electrical conductivity efficiency. In this paper, the surface of stainless steel electrodes was subjected to cleaning using a large-area plasma jet under atmospheric pressure. The wettability, chemical composition, and chemical state of the electrode surface were characterized using a water contact angle measuring instrument and X-ray photoelectron spectroscopy (XPS). The cleaning effect under different discharge parameters was systematically analyzed. The results revealed a significant reduction in the content of carbon pollutants on the surface of stainless steel electrodes, decreasing from 62.95% to a minimum of 37.68% after plasma cleaning. Moreover, the water contact angle decreased from 70.76° to a minimum of 29.31°, and the content of water molecules adsorbed on the surface decreased from 17.31% to a minimum of 5.9%. Based on the evolution process of micro-element content and chemical state on the surface of stainless steel electrode, the cleaning process of adhering substances on the surface by atmospheric pressure plasma was analyzed by the layered cleaning model for surface pollutants on stainless steel.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    冷等离子体处理是食品加工和保鲜领域的一项创新技术。它主要用于使微生物和酶失活,而无需加热和化学添加剂;因此,它通常被称为“清洁和绿色”技术。然而,在冷等离子体加工过程中,由于等离子体反应性物质和食品成分之间的潜在化学相互作用,可能会出现食品质量和安全方面的挑战。这篇综述旨在巩固和讨论冷等离子体对主要食品的化学成分以及物理和功能特性的影响的数据,包括乳制品,肉,坚果,水果,蔬菜,和谷物。我们强调冷等离子体如何诱导关键食品成分的化学改性,比如水,蛋白质,脂质,碳水化合物,维生素,多酚,和挥发性有机化合物。此外,我们讨论颜色的变化,pH值,冷等离子体处理诱导的感官特性及其与化学修饰的相关性。目前的研究表明,冷等离子体中的活性氧和氮可以氧化蛋白质,脂质,与食物基质直接接触时的生物活性化合物。营养素和生物活性化合物的减少,包括多不饱和脂肪酸,糖,糖多酚,和维生素,在乳制品中观察到,蔬菜,水果,和冷等离子体处理后的饮料。此外,观察到结构变化以及挥发性和非挥发性氧化产物的产生,影响颜色,风味,和食品的质地。然而,对干食物的影响,如种子和坚果,相对不那么明显。总的来说,这篇评论突出了缺点,挑战,以及与食品加工中的冷等离子体处理相关的机会。
    Cold plasma treatment is an innovative technology in the food processing and preservation sectors. It is primarily employed to deactivate microorganisms and enzymes without heat and chemical additives; hence, it is often termed a \"clean and green\" technology. However, food quality and safety challenges may arise during cold plasma processing due to potential chemical interactions between the plasma reactive species and food components. This review aims to consolidate and discuss data on the impact of cold plasma on the chemical constituents and physical and functional properties of major food products, including dairy, meat, nuts, fruits, vegetables, and grains. We emphasize how cold plasma induces chemical modification of key food components, such as water, proteins, lipids, carbohydrates, vitamins, polyphenols, and volatile organic compounds. Additionally, we discuss changes in color, pH, and organoleptic properties induced by cold plasma treatment and their correlation with chemical modification. Current studies demonstrate that reactive oxygen and nitrogen species in cold plasma oxidize proteins, lipids, and bioactive compounds upon direct contact with the food matrix. Reductions in nutrients and bioactive compounds, including polyunsaturated fatty acids, sugars, polyphenols, and vitamins, have been observed in dairy products, vegetables, fruits, and beverages following cold plasma treatment. Furthermore, structural alterations and the generation of volatile and non-volatile oxidation products were observed, impacting the color, flavor, and texture of food products. However, the effects on dry foods, such as seeds and nuts, are comparatively less pronounced. Overall, this review highlights the drawbacks, challenges, and opportunities associated with cold plasma treatment in food processing.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    这项研究继续讨论使用大气压等离子体(APP)反应器在空气中对聚合物进行表面改性。这些结果补充了以前关注非极性聚合物的研究。聚合物,如聚对苯二甲酸乙二醇酯,聚醚醚酮,和聚甲基丙烯酸甲酯,研究了含有结构键合的氧,代表一系列属性,如氧含量,结晶/无定形结构,极性,功能,和脂族/芳族结构。APP在亲水性聚合物表面上诱导优异的润湿性能,并在暴露0.5s内进行快速均匀的改性。非晶结构经历额外的修改以用于更长的曝光。此外,脂族链结构需要更长的等离子体暴露才能达到表面改性平衡。极性聚合物达到对应于约50°的最小水接触角的改性极限水平。表面极性平均增加大约2倍。在后处理恢复之后获得的粘附功的平衡值落在约100-120mJ/m2的有限范围内。通过产生氧化基团的表面官能度的增强主要取决于初始氧含量,并达到约40at。%氧气。经处理的极性表面的表面性能表现出良好的稳定性,与以前测试的非极性聚合物相当。
    This study continues the discussion on the surface modification of polymers using an atmospheric pressure plasma (APP) reactor in air. These results complement prior research focusing on nonpolar polymers. Polymers, such as polyethylene terephthalate, polyetheretherketone, and polymethyl methacrylate, containing structurally bonded oxygen are studied, representing a range of properties such as oxygen content, crystalline/amorphous structure, polarity, functionality, and aliphatic/aromatic structure. APP induces superior wetting properties on the hydrophilic polymer surfaces with rapid and uniform modification within 0.5 s of exposure. The amorphous structures undergo additional modification for longer exposure. Moreover, the aliphatic chain structures require longer plasma exposure to reach surface modification equilibrium. The polar polymers reach a limit level of modification corresponding to a minimum water contact angle of about 50°. The surface polarity increases on average by a factor of approximately two. The equilibrium values of the adhesion work attained after post-processing recovery fall within a limited range of about 100-120 mJ/m2. The enhancement of surface functionality through the creation of oxidized groups primarily depends on the initial oxygen content and reaches a limit of about 40 at.% oxygen. The surface properties of the treated polar surfaces exhibit good stability, comparable to that of the previously tested nonpolar polymers.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    在本文中,描述了各种几何布置中的冷介电阻挡放电(DBD)等离子体的智能集成,以及在大气压下对纳米材料的激光烧蚀。通过纳秒(ns)激光(波长:1064nm,脉冲持续时间:30ns),使用5J-cm-2的通量,重复频率为10Hz。在垂直和倾斜等离子体流中产生的纳米材料,表面放电和气流,进行了比较。利用表面放电通过改变表面固有行为显着提高了材料的附着力,诱导预期的表面能活化,化学变化,并形成密集的固体结构。在所有条件下,材料始终保持其结晶性质,元素组成,和紫外线发射特性。这些初步发现为进一步的研究提供了希望,建议在灵活的环境中制造复杂材料的途径。这种新的进步可以促进生物医学的应用,催化作用,Pharmaceutical,和外科设备领域。
    In this paper, smart integration of cold dielectric barrier discharge (DBD) plasma in various geometrical arrangements with laser ablation at atmospheric pressure for nanomaterial was described. A composite Co:ZnO target was ablated in an airflow by a nanosecond (ns) laser (wavelength: 1064 nm, pulse duration: 30 ns) using fluence of 5 J-cm-2 at a repetition rate of 10 Hz. The nanomaterial produced under vertical and oblique plasma streams, surface discharge and gas flow, were compared. Utilization surface discharge markedly improved the material adhesion by altering surface intrinsic behavior, inducing anticipated surface energy activation, chemical changes, and the formation of a densely packed solid structure. Under all conditions, the material consistently retained its crystalline nature, elemental composition, and ultraviolet emission characteristics. These preliminary findings hold promise for additional research, suggesting avenues for making complex materials in a flexible environment. Such new advancements could facilitate applications in the biomedical, catalysis, pharmaceutical, and surgical device domains.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    骨内植入物的能量状态取决于材料,制造技术,清洁程序,灭菌方法,和手术操作。带有正电荷的植入物表面具有亲水性,从而促进对成骨相互作用至关重要的重要血浆蛋白的吸收。控制表面电荷的技术涉及氧化等过程,化学和地形调整以及非热等离子体(NTP)处理的应用。在大气压和室温下的NTP可以诱导化学和/或物理反应,其通过表面能变化增强润湿性。因此,NTP已被用于修饰与邻近的组织细胞和蛋白质连接的骨内膜植入物的氧化层。结果表明,如果在植入前应用,在早期愈合的关键阶段,NTP加强了与周围硬组织结构的相互作用,从而促进快速骨形成。此外,在此期间,已发现NTP导致增强的生物力学固定。因此,NTP的应用可能是改善愈合结局的一种实用可靠的方法.这篇综述旨在深入探索NTP在骨内膜植入物上应用时应考虑的参数。此外,解决了NTP对骨整合的短期和长期影响,以及NTP在牙周病治疗中的最新进展。
    The energy state of endosteal implants is dependent on the material, manufacturing technique, cleaning procedure, sterilization method, and surgical manipulation. An implant surface carrying a positive charge renders hydrophilic properties, thereby facilitating the absorption of vital plasma proteins crucial for osteogenic interactions. Techniques to control the surface charge involve processes like oxidation, chemical and topographical adjustments as well as the application of nonthermal plasma (NTP) treatment. NTP at atmospheric pressure and at room temperature can induce chemical and/or physical reactions that enhance wettability through surface energy changes. NTP has thus been used to modify the oxide layer of endosteal implants that interface with adjacent tissue cells and proteins. Results have indicated that if applied prior to implantation, NTP strengthens the interaction with surrounding hard tissue structures during the critical phases of early healing, thereby promoting rapid bone formation. Also, during this time period, NTP has been found to result in enhanced biomechanical fixation. As such, the application of NTP may serve as a practical and reliable method to improve healing outcomes. This review aims to provide an in-depth exploration of the parameters to be considered in the application of NTP on endosteal implants. In addition, the short- and long-term effects of NTP on osseointegration are addressed, as well as recent advances in the utilization of NTP in the treatment of periodontal disease.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    通过原位碘(I2)掺杂提高聚吡咯(PPy)纳米结构薄膜的导电性,这项研究提出了一个大气压等离子体反应器(APPR),其中加热的I2掺杂剂蒸气通过毛细管电极作为电极放电点火。与单体气体分开引入反应器中的大量加热的I2蒸气可以经由毛细管电极被强等离子体有效地活化。特别是,通过适当调整APPR中的钝体位置来获得密集等离子体。根据ICCD和OES的结果,观察到通过毛细管喷嘴电极注入的I2蒸气形成I2电荷物质。形成的I2物质可以直接参与原位生长I2掺杂的PPy膜。因此,使用所提出的APPR生长的原位I2掺杂的PPy纳米结构膜表现出15.3μm的更高厚度和良好的导电性,与相应的非掺杂薄膜相比。
    To improve the electrical conductivity of polypyrrole (PPy) nanostructure film through in situ iodine (I2) doping, this study proposes an atmospheric pressure plasma reactor (APPR) where heated I2 dopant vapor is fed through capillary electrodes that serve as electrodes for discharge ignition. A large amount of the heated I2 vapor introduced into the reactor separately from a monomer gas can be effectively activated by an intense plasma via capillary electrodes. In particular, intensive plasma is obtained by properly adjusting the bluff body position in the APPR. Based on the ICCD and OES results, the I2 vapor injected through the capillary nozzle electrode is observed to form I2 charge species. The formed I2 species could directly participate in growing in situ I2-doped PPy films. Thus, in situ I2-doped PPy nanostructure films grown using the proposed APPR exhibit higher thicknesses of 15.3 μm and good electrical conductivities, compared to the corresponding non-doped films.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    在过去的十年里,利用大气压等离子体(APP)作为辐射源的小型化光学发射光谱(OES)系统在痕量重金属分析中表现出令人印象深刻的能力。作为分析系统的核心,APP来源具有独特的属性,如紧凑的尺寸,重量轻,低能量需求,易于制造,和相对较低的制造成本。这篇重要的评论集中在基于APP的OES系统用于测定重金属的最新进展。包括样品导入方式在内的技术细节的影响,采样体积,样品流速,全面讨论了溶液的pH值对血浆稳定性和分析信号强度的影响。此外,该评论强调了这些技术面临的分析挑战,并强调了重金属检测领域进一步发展的机会。
    Over the past decade, miniaturized optical emission spectrometry (OES) systems utilizing atmospheric pressure plasmas (APPs) as radiation sources have exhibited impressive capabilities in trace heavy metal analysis. As the core of the analytical system, APPs sources possess unique properties such as compact size, light weight, low energy requirement, ease of fabrication, and relatively low manufacturing cost. This critical review focuses on recent progress of APP-based OES systems employed for the determination of heavy metals. Influences of technical details including the sample introduction manner, the sampling volume, the sample flow rate, the pH of the solutions on the plasma stability and the intensity of analytical signals are comprehensively discussed. Furthermore, the review emphasizes the analytical challenges faced by these techniques and highlights the opportunities for further development in the field of heavy metal detection.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号