CNTs

CNT
  • 文章类型: Journal Article
    预计由碳纳米管(CNT)和铜(Cu)制成的复合材料同时具有机械性能和电性能,但高含量碳纳米管的低损伤分散和高质量复合材料一直是研究的难点。在本文中,制备了高含量CNTs/Cu复合材料。烧结方法的影响,烧结温度,定向轧制和相对密度上的碳纳米管含量,研究了复合材料的硬度和电导率。通过球磨实现了高含量CNTs在Cu基体中的均匀分散,烧结和轧制,并且该过程没有对CNT造成更大的损害。比较了放电等离子烧结(SPS)和真空热压烧结(HPS)制备的复合材料的性能,并确定了SPS的最佳工艺参数。当CNT含量为2重量%时。%,硬度为134.9HBW,仍然是纯铜的2.3倍,电导率最高,达到78.4%IACS。本研究为高含量CNTs/Cu复合材料的高质量制备和性能评价提供了重要参考依据。
    It is expected that composites made of carbon nanotubes (CNT) and copper (Cu) display both mechanical and electrical properties, but the low damage dispersion and high-quality composite of high-content CNTs have always been research difficulties. In this paper, high-content CNTs/Cu composites were prepared. The effects of the sintering method, sintering temperature, directional rolling and the CNTs\' content on the relative density, hardness and electrical conductivity of the composites were studied. The uniform dispersion of high-content CNTs in Cu matrix was achieved by ball milling, sintering and rolling, and the processes did not cause more damage to the CNTs. The properties of composites prepared by spark plasma sintering (SPS) and vacuum hot pressing sintering (HPS) were compared, and the optimum process parameters of SPS were determined. When the CNTs\' content is 2 wt.%, the hardness is 134.9 HBW, which is still 2.3 times that of pure Cu, and the conductivity is the highest, reaching 78.4%IACS. This study provides an important reference for the high-quality preparation and performance evaluation of high-content CNTs/Cu composites.
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  • 文章类型: Journal Article
    通过自蔓延反应和热压处理合成的包含稀土钕(Nd)掺杂的M型钡铁氧体(BaM)与CNT(碳纳米管)和聚乙烯的共混物的复合板。利用X射线衍射(XRD)分析了板的微观特征,傅里叶变换红外分光光度法(FTIR),热重分析(TGA),拉曼,和扫描电子显微镜(SEM)分析技术。使用矢量网络分析仪评估了它们在8.2至18GHz频率范围内的微波吸收性能。结果表明,碳纳米管在Nd-BaM吸收体表面形成了导电网络,显着提高吸收性能和扩大吸收带宽。此外,使用德拜理论研究了电介质极化弛豫,分析Cole-Cole半圆.观察到表现出最佳吸收性能的样品表现出最半圆,说明介质极化弛豫现象会增加样品的介电弛豫损耗。这些发现为轻质制备BaM基吸波材料提供了有价值的数据支持。
    Composite plates comprising a blend of rare earth neodymium-(Nd) doped M-type barium ferrite (BaM) with CNTs (carbon nanotubes) and polyethylene WERE synthesized through a self-propagating reaction and hot-pressing treatment. The plates\' microscopic characteristics were analyzed utilizing X-ray diffraction (XRD), Fourier transform infrared spectrophotometry (FTIR), thermo-gravimetric analysis (TGA), Raman, and scanning electron microscopy (SEM) analytical techniques. Their microwave absorption performance within the frequency range of 8.2 to 18 GHz was assessed using a vector network analyzer. It showed that CNTs formed a conductive network on the surface of the Nd-BaM absorber, significantly enhancing absorption performance and widening the absorption bandwidth. Furthermore, dielectric polarization relaxation was investigated using the Debye theory, analyzing the Cole-Cole semicircle. It was observed that the sample exhibiting the best absorbing performance displayed the most semicircles, indicating that the dielectric polarization relaxation phenomenon can increase the dielectric relaxation loss of the sample. These findings provide valuable data support for the lightweight preparation of BaM-based absorbing materials.
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  • 文章类型: Journal Article
    研究了以SrTiO3/碳纳米管(CNT)为纳米填料的聚偏氟乙烯(PVDF)聚合物纳米复合膜的光学性能。通过溶液流延技术制备了PVDF/SrTiO3/CNTs薄膜。X射线衍射(XRD)傅里叶变换红外光谱(FTIR),和扫描电子显微镜(SEM)分析证实了SrTiO3/CNTs掺入PVDF基质中。纳米填料的添加影响了晶体结构,形态学,和薄膜的光学性能。SEM图像显示球晶形态,它是结晶聚合物链的球形聚集体。SrTiO3/CNTs纳米填料的加入改性了聚合物的电子结构,导致能隙的变化。添加0.1wt%的SrTiO3/CNTs增加了带隙,折射率,PVDF薄膜的非线性光学特性。这些改进表明这些纳米复合膜在光电应用如太阳能电池中的潜力,图像传感器,和有机发光二极管。
    The optical properties of polyvinylidene fluoride (PVDF) polymer nanocomposite films incorporating SrTiO3/carbon nanotubes (CNTs) as nanofillers are investigated. PVDF/SrTiO3/CNTs films were prepared by the solution casting technique. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses confirmed the incorporation of SrTiO3/CNTs into the PVDF matrix. The addition of nanofillers influenced the crystalline structure, morphology, and optical properties of the films. SEM images showed spherulite morphology, which is a spherical aggregate of crystalline polymer chains. The addition of a SrTiO3/CNTs nanofiller modified the polymer\'s electronic structure, causing a variation in the energy gap. The addition of SrTiO3/CNTs at 0.1 wt% increased the band gap, refractive index, and nonlinear optical properties of the PVDF films. These improvements indicate the potential of these nanocomposite films in optoelectronic applications such as solar cells, image sensors, and organic light-emitting diodes.
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  • 文章类型: Journal Article
    本文的目的是通过实验确定环境的作用,由基础油(PAO)组成,碳纳米材料,和可选的其他添加剂,以及与润滑膜接触的金属种类,在保护膜形成过程中刺激二烷基二硫代磷酸锌(ZDDP)添加剂的有效性。本文重点研究了碳纳米结构在摩擦学过程中能量传输和转化中的作用。加入了用于喷气燃料的抗静电添加剂(ASA)(不用于润滑油),以干扰通过润滑剂膜的能量传导(电荷)过程,从而确定这种干扰如何影响ZDDP摩擦反应的动力学,因此,线性磨损。为了实现这一研究目标,使用了两种类型的摩擦学测试设备:安东帕摩擦计(TRB)和摩擦电动摩擦计(TET)。本研究的新颖之处在于使用用于喷气燃料的抗静电添加剂干扰通过润滑膜的电荷/能量流动的方法。ASA,以影响该能量对ZDDP的抗磨性能的影响。得出以下结论:(1)碳基纳米结构,即,CNT,AuCNT,石墨烯,石墨烯和富勒烯,能够改变ZDDP在摩擦过程中的化学反应速率;(2)碳纳米管具有催化ZDDP摩擦化学反应的能力,而石墨烯和富勒烯不能有效地执行此操作;(3)AuCNT在ZDDP的摩擦反应过程中起到抑制剂的作用;(4)通过释放电荷/能量,ASA,与CNT和AuCNT合作显著降低ZDDP反应的速率。
    The aim of this article is to experimentally determine the role of the environment, consisting of a base oil (PAO), carbon nanomaterials, and optional other additives, as well as the kind of metal in contact with the lubrication film, in the stimulation of zinc dialkyldithiophosphate (ZDDP) additives\' effectiveness during protective film formation. This paper focuses on the role of carbon nanostructures in energy transportation and conversion during tribological processes. An antistatic additive (ASA) (not used in lubricating oils) for jet fuels was added to disturb the process of energy conduction (electric charges) through the lubricant film and thus determine how this disturbance affects the kinetics of the ZDDP triboreaction and, consequently, the linear wear. To achieve this research goal, two types of tribological testing devices were used: an Anton Paar tribometer (TRB) and a triboelectric tribometer (TET). The novelty of the present research is in the use of the method for disturbing the flow of charge/energy through the lubricant film with an antistatic additive for jet fuels, ASA, to influence the impact of this energy on the antiwear properties of ZDDP. The following conclusions were drawn: (1) carbon-based nanostructures, i.e., CNTs, AuCNTs, graphene, and fullerenes, are able to change the rate of chemical reactions of ZDDP during tribological processes; (2) CNTs have the ability to catalyze tribochemical reactions of ZDDP, while graphene and fullerenes are not able to perform this effectively; (3) AuCNT takes the role of an inhibitor during ZDDP\'s triboreaction; and (4) by discharging electric charge/energy, ASA, in cooperation with CNT and AuCNT significantly reduces the rate of the ZDDP reaction.
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  • 文章类型: Journal Article
    在本文中,通过第一性原理研究了碳纳米管缺陷和铜表面氧化层对碳纳米管-铜界面的影响。无缺陷的CNT-Cu界面,Stone-Wales缺陷CNT-Cu界面,单孔和双孔缺陷CNT-Cu界面,并对Cu2O-Cu界面进行了模拟计算。通过模拟差分电荷密度,原子种群,界面模型的键种群和状态密度,分析了碳纳米管增强铜基复合材料制备过程中各种缺陷对复合材料界面结合和导电性能的影响,为CNT/Cu复合材料的制备提供了理论指导。之后,通过不同的轧制变形工艺制备了不同碳纳米管缺陷含量的铜基复合材料。测试了它们的硬度和电导率,并且结果与通过第一性原理计算获得的结果一致。
    In this paper, the effects of carbon nanotube defects and a copper surface oxide layer on a carbon nanotube-copper interface were studied via first-principles. A defect-free CNT-Cu interface, Stone-Wales defect CNT-Cu interface, single-hole and double-hole defect CNT-Cu interface, and Cu2O-Cu interface were simulated and calculated. By simulating the differential charge density, atomic population, bond population and density of states of the interface model, the effects of various defects on the interface bonding and electrical conductivity of the composites during the preparation of the CNT-reinforced copper matrix composites were analyzed, which provided theoretical guidance for the preparation of CNT/Cu composites. After that, copper matrix composites with different CNT defect contents were prepared via different rolling deformation processes. Their hardness and electrical conductivity were tested, and the results were consistent with the results obtained via the first-principles calculations.
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  • 文章类型: Journal Article
    碳纳米管(CNT)和苯乙烯-丁二烯-苯乙烯(SBS)由于其优异的性能而被用作沥青密封剂中的增强改性剂,能有效改善密封胶的内部结构,增强其力学性能。基于这样的背景,通过正交实验方法对两种SBS/CNT改性沥青密封胶进行了鉴定和选择,并与两种市售密封胶进行了比较。软化点,流量值,多温度频率扫描测试,采用多次应力蠕变恢复试验研究了4种密封胶的高温流变性能和耐老化性能。总体评价表明,密封剂化合物的制备材料的比例为1重量%的CNT掺杂,5重量%的SBS掺杂,和5重量%的糠醛提取油掺杂。结果表明,SBS和CNTs的加入更显著地提高了密封胶的抗疲劳性能。有了CAM模型,C1.0S5F5反映了更好的弛豫特性,这更好地避免了密封剂施工后的二次开裂。有了汉堡模型,C1.0S5F5在重交通条件下表现出优异的抗变形性。总之,常规性能指标,如SBS/CNT改性沥青密封胶的软化点和流动值,与市售密封剂相比,可以满足规范要求,并显示出良好的高温稳定性和抗老化性能。
    Carbon nanotubes (CNTs) and styrene-butadiene-styrene (SBS) are used as reinforcing modifiers in asphalt sealants due to their excellent properties, which can effectively improve the internal structure of the sealant and enhance its mechanical properties. Based on this background, two SBS/CNT-modified asphalt sealants were identified and selected by the orthogonal experimental method and compared with two commercially available sealants. The softening point, flow value, multi-temperature frequency scan test, and multiple stress creep recovery test were used to study the high-temperature rheological properties and aging resistance of four types of sealants. The overall evaluation shows that the proportion of the sealant compound\'s preparation material is 1% by weight of CNT doping, 5% by weight of SBS doping, and 5% by weight of furfural-extracted-oil doping. The results show that the addition of SBS and CNTs more significantly improves the fatigue resistance of the sealants. With the CAM model, C1.0S5F5 reflects a better relaxation property, which better avoids secondary cracking after the construction of the sealant. With the Burgers model, C1.0S5F5 shows excellent deformation resistance under heavy traffic conditions. In summary, conventional performance indicators, such as the softening point and flow value of SBS/CNT-modified asphalt sealants, can meet the specification requirements and show good high-temperature stability and anti-aging properties compared to commercially available sealants.
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  • 文章类型: Journal Article
    HCV,丙型肝炎病毒,是一种对肝脏造成损害的病毒.慢性感染或缺乏治疗都会增加发病率,除非是急性感染,因为身体在没有任何干预的情况下清除病毒。此外,这种病毒有许多基因型,直到现在,目前还没有一种单一的治疗方法能够同时影响和治疗所有这些基因型。这篇综述将讨论主要和最常用的旧治疗方法,IFN-a,PEGIFN-a,利巴韦林,Celgosvir,和索非布韦单独和与其他药物的组合及其缺点。与独立给药相比,应联合给药,以提高对病毒的作用,就像sofosbuvir一样。由于这些原因,需要新的治疗方法和诊断工具,纳米技术的规则来到这里。碳纳米管的作用,树枝状聚合物,和富勒烯将被讨论。CNT,碳纳米管,是由圆柱形石墨片组成的一维结构,主要用于HCV的诊断目的。树枝状聚合物,三维高度分支结构,是大分子,提供更好的药物输送和治疗选择,由于其独特的结构,可以修改,生产多功能类型;每个都有独特的属性。富勒烯是笼状结构,与碳纳米管密切相关,并且由可以被其他原子取代的碳原子组成,这些原子反过来为这些碳基材料提供了无限的用途。富勒烯规则是独特的,因为它具有防止病毒结合和作用于病毒复制酶的两种机制。然而,他们的费用需要确定;否则,它会导致细胞毒性。最后,尚未对纳米技术对HCV的作用进行综述.
    HCV, hepatitis C virus, is a virus that causes damage to the liver. Both chronic infection or lack of treatment increase morbidity except if it is an acute infection, as the body clears the virus without any intervention. Also, the virus has many genotypes, and until now, there has yet to be a single treatment capable of affecting and treating all these genotypes at once. This review will discuss the main and most used old treatments, IFN-a, PEG IFN-a, Ribavirin, Celgosvir, and sofosbuvir alone and with the combination of other drugs and their drawbacks. They should be given in combination to improve the effect on the virus compared with being administrated independently, as in the case of sofosbuvir. For these reasons, the need for new treatments and diagnostic tools arises, and the rule of nanotechnology comes here. The role of carbon nanotubes, dendrimers, and fullerenes will be discussed. CNTs, carbon nanotubes, are one-dimensional structures composed of a cylindrical sheet of graphite and are mainly used for diagnostic purposes against HCV. Dendrimers, three-dimensional highly branched structures, are macromolecules that provide better drug delivery and treatment options due to their unique structure that can be modified, producing versatile types; each has unique properties. Fullerenes which are cage like structures derived and closely related to CNTs, and composed of carbon atoms that can be substituted by other atoms which in return open unlimited usage for these carbon based materials. Fullerenes rule is unique since it has two mechanisms that prevent the virus from binding and acting on the virus-replicating enzyme. However, their charge needs to be determined; otherwise, it will lead to cytotoxicity. Lastly, no review has been done on the role of nanotechnology against HCV yet.
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  • 文章类型: Journal Article
    工程水泥基复合材料(ECCs)是具有应变硬化和多开裂特性的水泥基复合材料。ECC具有多尺度缺陷,包括纳米级水合硅酸盐凝胶,微米级的毛孔,和毫米级裂缝。通过使用毫米级聚乙烯(PE)纤维,微尺度碳酸钙晶须(CWs),和纳米级碳纳米管(CNT)作为外掺杂纤维,形成了多尺度增强系统,并测试了多尺度纤维对ECCs力学性能的影响。Box-Behnken实验设计方法,这是一种响应面方法,用于构造二次多项式回归方程以优化ECC设计并提供ECC混合比例的优化。这项研究的结果表明,由PE纤维组成的多尺度增强系统,CWs,和碳纳米管增强了ECCs的力学性能。CW对高延性纤维增强水泥基复合材料的抗压强度影响最大,其次是CNT和PE纤维。PE纤维对高延展性纤维增强水泥基复合材料的弯曲和拉伸强度影响最大,其次是CW和CNT。最终的优化结果表明,当ECC基体掺杂1.55%的PE纤维时,2.17%CW,和0.154%的碳纳米管,抗压强度,抗弯强度,基体的拉伸强度最优。
    Engineered cementitious composites (ECCs) are cement-based composite materials with strain-hardening and multiple-cracking characteristics. ECCs have multiscale defects, including nanoscale hydrated silicate gels, micron-scale capillary pores, and millimetre-scale cracks. By using millimetre-scale polyethylene (PE) fibres, microscale calcium carbonate whiskers (CWs), and nanoscale carbon nanotubes (CNTs) as exo-doped fibres, a multiscale enhancement system was formed, and the effects of multiscale fibres on the mechanical properties of ECCs were tested. The Box-Behnken experimental design method, which is a response surface methodology, was used to construct a quadratic polynomial regression equation to optimise ECC design and provide an optimisation of ECC mix proportions. The results of this study showed that a multiscale reinforcement system consisting of PE fibres, CWs, and CNTs enhanced the mechanical properties of ECCs. CWs had the greatest effect on the compressive strengths of highly ductile-fibre-reinforced cementitious composites, followed by CNTs and PE fibres. PE fibres had the greatest effect on the flexural and tensile strengths of high-ductility fibre-reinforced cementitious composites, followed by CWs and CNTs. The final optimisation results showed that when the ECC matrix was doped with 1.55% PE fibres, 2.17% CWs, and 0.154% CNTs, the compressive strength, flexural strength, and tensile strength of the matrix were optimal.
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  • 文章类型: Journal Article
    用于多向应变检测的柔性应变传感器在复杂的人机交互(HCI)应用中至关重要。然而,提高传感器的各向异性和灵敏度的多方向检测在一个简单而有效的方法仍然是一个重要的问题。因此,这项研究提出了一种具有各向异性和高灵敏度的柔性应变传感器,该传感器基于高纵横比V型槽阵列和铁纳米线和碳纳米管(FeNWs/CNT)的混合导电网络。传感器表现出显著的各向异性,两个相互垂直的方向之间的应变检测灵敏度差异高达35.92倍。此外,传感器的动态性能表现出良好的响应速率,范围从223ms到333ms。即使经过1000次测试循环,传感器也能保持稳定和一致的性能。此外,使用手推车的远程控制应用对构造的柔性应变传感器进行测试,证明了其在实际HCI系统中的高使用潜力。这项研究为HCI领域的柔性应变传感器的开发提供了显着的竞争优势。
    Flexible strain sensors for multi-directional strain detection are crucial in complicated hman-computer interaction (HCI) applications. However, enhancing the anisotropy and sensitivity of the sensors for multi-directional detection in a simple and effective method remains a significant issue. Therefore, this study proposes a flexible strain sensor with anisotropy and high sensitivity based on a high-aspect-ratio V-groove array and a hybrid conductive network of iron nanowires and carbon nanotubes (Fe NWs/CNTs). The sensor exhibits significant anisotropy, with a difference in strain detection sensitivity of up to 35.92 times between two mutually perpendicular directions. Furthermore, the dynamic performance of the sensor shows a good response rate, ranging from 223 ms to 333 ms. The sensor maintains stability and consistent performance even after undergoing 1000 testing cycles. Additionally, the constructed flexible strain sensor is tested using the remote control application of a trolley, demonstrating its high potential for usage in practical HCI systems. This research offers a significant competitive advantage in the development of flexible strain sensors in the field of HCI.
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  • 文章类型: Journal Article
    在这项研究中,碳纳米管(CNT)通过重氮盐反应官能化,以将极性基团引入其表面。将这些官能化的CNT(FCNT)以不同的负载量(0wt%,0.5wt%,1wt%,1.5wt%)并用于静电纺丝。结果表明,添加FCNT有助于生产具有小纤维直径的PPO面纱。面纱在CF/EP复合层压板中用作夹层。模式I和模式II层间断裂韧性测试表明,含有0.5wt%FCNT的PPO面纱表现出最佳的增韧作用。GICini和GIIC比未增韧的样品有大约120%和180%的改进,分别,比不含CNT的PPO面纱高出15%和26%,分别。还使用扫描电子显微镜(SEM)分析了增韧机理。
    In this study, carbon nanotubes (CNTs) are functionalized through diazonium salt reaction to introduce polar groups onto their surfaces. These functionalized CNTs (FCNTs) are added into PPO solutions at different loadings (0 wt%, 0.5 wt%, 1 wt%, 1.5 wt%) and used for electrospinning. The results show that the addition of FCNTs facilitate the production of PPO veils having small fiber diameters. The veils are used as interleaves in CF/EP composite laminates. The Mode I and Mode II interlaminar fracture toughness tests reveal that PPO veils containing 0.5 wt% FCNTs exhibit the optimal toughening. GICini and GIIC have an improvement of approximately 120% and 180% over the untoughened samples, respectively, which is 15% and 26% higher than that of PPO veils containing no CNTs, respectively. The toughening mechanism is also analyzed using scanning electron microscopy (SEM).
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