基于SWCNTs薄膜的多谐振环太赫兹超表面传感特性

基于单壁碳纳米管(SWCNTs)薄膜,构建了一种具有多频窄带共振效应的新型太赫兹(THz)超表面。深入分析了周期性微结构单元参数对超表面的共振特性的影响;通过仿真及理论计算对器件的共振耦合机理进行研究,二者具有较好的一致性。通过在超表面覆盖不同折射率的介质层,分析这种THz超表面器件的折射率传感特性,灵敏度分析结果显示,该超表面器件可实现最高64 GHz/RIU的折射率传感。

SWCNTs的制备及其在生物传感器中的应用前景

SWCNTs独特的电子结构和几何形状赋予了它独特的荧光特性,具有良好的生物相容性和优异的光学性质,还具有高度均匀性以及小孔缺陷,易于处理。因此,它们被广泛应用于生物医学成像、生物传感和药物输送领域。本文对SWCNTs的制备及在荧光生物传感器方向的应用研究进展进行了综述,并对其应用前景进行展望。

黄连总生物碱Pluronic/SWCNTS给药系统的制备及初步评价

目的:优化黄连总生物碱的提取工艺,构建功能化Pluronic/SWCNTS负载黄连总生物碱的给药系统,并对其进行质量评价。方法:采用星点设计-效应面法优化黄连总生物碱提取工艺;采用超声法制备载药体系,以载药量为指标,通过单因素考察优化处方工艺,并对给药系统的形态、粒径及稳定性等进行评价。结果:黄连总生物碱Pluronic/SWCNTS给药系统的载药量为9.5%,平均粒径为(220.1±1.5)nm,放置15 d可长期稳定存在。结论:黄连总生物碱Pluronic/SWCNTS给药系统制备成功,具有作为口服纳米给药系统的潜力。

PAN/SWCNTs复合纳米纤维纱线的制备及其性能

采用改进的静电纺丝装置,分别制备了纯聚丙烯腈(PAN)纳米纤维纱线和不同单壁碳纳米管(SWCNTs)质量分数的PAN/SWCNTs复合纳米纤维纱线.利用扫描电子显微镜、透射电子显微镜、傅里叶红外-拉曼光谱仪和X射线多晶衍射仪分别对复合纳米纤维纱线进行了形貌和直径表征、分子结构分析、结晶结构分析,并测试了不同SWCNTs质量分数对复合纳米纤维纱线力学性能的影响.结果表明:不同SWCNTs质量分数的PAN/SWCNTs复合纳米纤维纱线均具有良好的形态且沿着纱线轴向有序排列;随着SWCNTs质量分数的增加,纱线和纤维的直径均呈现减小的趋势,并且纤维中的串珠增多;碳纳米管沿纤维轴向均匀分布;碳纳米管的加入没有产生新的特征峰,但PAN的峰值有所减弱或增强;碳纳米管的加入改变了PAN的结晶性能;当SWCNTs质量分数为5%时,复合纳米纤维纱线的拉伸强度达到最高值为24.25 MPa.

A ternary phased SnO_2-Fe_2O_3/SWCNTs nanocomposite as a high performance anode material for lithium ion batteries

A new SnO2-Fe2O3/SWCNTs（single-walled carbon nanotubes） ternary nanocomposite was first synthesized by a facile hydrothermal approach.SnO2 and Fe2O3 nanoparticles（NPs） were homogeneously located on the surface of SWCNTs,as confirmed by X-ray diffraction（XRD）,transmission electron microscope（TEM） and energy dispersive X-ray spectroscopy（EDX）.Due to the synergistic effect of different components,the as synthesized SnO2-Fe2O3/SWCNTs composite as an anode material for lithium-ion batteries exhibited excellent electrochemical performance with a high capacity of 692 mAh·g-1 which could be maintained after 50 cycles at 200 mA·g-1.Even at a high rate of2000 mA·g-1,the capacity was still remained at 656 mAh·g-1.

Construction of a Bronsted-Lewis solid acid catalyst La-PW-SiO_(2)/SWCNTs based on electron withdrawing effect of La(Ⅲ)onπbond of SWCNTs for biodiesel synthesis from esterification of oleic acid and methanol

A novel solid Bronsted-Lewis acid catalyst La-PW-SiO_(2)/SWCNTs(single-wall carbon nanotubes)was synthesized from the synergistic modification of H_(3)PW_(12)O_(40)(HPW)by single-walled carbon nanotubes functionalized with sidewall hydroxyl groups(SWCNTs–OH)and La^(3+) via sol–gel method.The freshly prepared catalyst was characterized by several methods,and the catalytic activity and stability of it were studied from the esterification of oleic acid and methanol.Results showed that the highest conversion of oleic acid was 93.1%(mass)and maintained as high as 88.7%(mass)after six cycles of La-PW-SiO_(2)/SWCNTs.The high catalytic activity and stability of La-PW-SiO_(2)/SWCNTs can be attributed to the strong electron withdrawing effect of La^(3+) on π bond of SWCNTs,because it can facilitate the formation of a large number of strong Lewis acid sites.Therefore,the reduction of catalytic activity of a solid acid catalyst due to the fact that hydration reaction of its Bronsted acid sites can be effectively reduced.La-PW-SiO_(2)/SWCNTs can be an efficient and economical catalyst,because it shows good catalytic activity and stability.

Spectroscopic Studies of Nanocomposites Based on PEO/PVDF Blend Loaded by SWCNTs

Novel nanocomposites of PEO/PVDF loaded by different contents of SWCNTs were prepared. From UV-Vis spectra, the estimated values of absorption edge, absorption coefficient, energy of tail and extinction coefficient were calculated. The exponential decay tail at low energy is due to the presence of localized states in the energy band gap. The shift of Raman spectra indicates the possibility of SWCNTs to be attached with OH group in the side chain of polymer molecules. The X-ray measurements indicate that the addition of SWCNTs is a rich amorphous region in polymeric matrices and complete complexation between PEO/PVDF blend and SWCNTs. The SEM images show smooth surface of PEO/PVDF and they become rough with single rod with a good distribution within surface region in polymeric matrices after loading SWCNTs. TEM images showed that SWCNTs were dispersed well in polymeric matrices. The broken ends of nanotubes were showing that the SWCNTs were broken apart rather than from at the fracture surface. The films show some defects like rags on the tube walls. There are some black regions in TEM images attributed to amorphous nature carbon. The prepared nanocomposites are very useful in technical application.

Single Wall Carbon Nanotubes (SWCNTs) as (i) Type in the Photovoltaic Cell of Nano-Dimensions

In this paper, a new modified approach to design the photovoltaic cell has been presented by adding Single Wall Carbon Nanotubes (SWCNTs) as type (i). The main issue is to increase the efficiency of the photovoltaic cell, on the other hand, to exploit a larger range of electromagnetic wave frequencies, specifically a range within terahertz (THz) frequency domain, using 3D EM computer simulation technology (CST). It is clear in the normal PV cell start working at frequency of 500 THz, while the frequency at which the PV cell with SWCNTs operates is much less and it is close to zero, on the other hand, the PV cell with SWCNTs needs a larger cross-section area of 2800 nm2 to operate at frequency of 500 THz. This cell can be easily produced industrially, which means increases the efficiency of solar cell.

Interaction between SWCNTS and the mitochondriai electron transport chain

Objective： To investigate the effect of single-wall carbon nanotubes on the mitochondrial electron transport chain （METC） of tumor cells. Methods： Human hepatocarcinoma cell line HepG2 were cultured in DMEM medium （Hyclone） supplemented with 10% fetal calf serum （Gibco） in a atmosphere of 95% oxygen and 5% carbon dioxide under 37C. Cells were exposed by adding SWCNTs in the medium in concentrations of 1.5 - 12btg/ml. HepG2 cells exposed to narmal saline were used as control. The cells were collected after at 24h. The mitochondrial of HepG2 cells were obtained by density gradient centrifugation and were examined under transmis- sion electron microscope （TEM） . Four enzyme activity of the mitochondrial electron transport chain （METC） were determined by enzyme mark instrument. Results：

Free-standingβ-Ta_(2)O_(5)/SWCNTs composite film for high-rate Li-ion storage

The rapid development of portable and wearable electronic devices is responding to the urgent demand for high-efficiency flexible energy storage devices.Flexible supercapacitors,showing long cycle life,high power density,and good safety,are considered ideal candidates.Nevertheless,the relatively low energy density restricts their practical applications.With a large dielectric constant of 18-46,Ta_(2)O_(5)-based materials typically exhibit excellent electron-binding ability,which is critical for enhancing the energy density of supercapacitors.In this work,the free-standingβ-Ta_(2)O_(5)/single-walled carbon nanotubes(SWCNTs)composite film was prepared,with a highβ-Ta_(2)O_(5)loading of over 70%.By anchoringβ-Ta_(2)O_(5)nanoparticles onto the surface of SWCNTs,the system’s flexibility and conductivity were significantly enhanced,which also facilitated the intercalation electrodynamics of metal cations.As a result,the flexibleβ-Ta_(2)O_(5)/SWCNTs film exhibits excellent Li-ion storage performance,with a high volumetric specific capacitance of 392.3 F cm^(-3)at the scan rate of 10 mV s^(-1)and 198.9 F cm^(-3)at 500 mV s^(-1).In addition,the asymmetric device,assembled by theβ-Ta_(2)O_(5)/SWCNTs and activated carbon films,shows a high energy density of 45.5 Wh kg^(-1)at the power density of 10.8 kW kg^(-1).This technique opens up a new avenue for improving the energy density and rate performance of flexible supercapacitors.

Pluronic/SWCNTs纳米复合物的制备及对罗丹明123在Caco-2细胞摄取影响的初步研究

目的:优化Pluronic/SWCNT纳米复合物的制备工艺,并考察其对小肠P-gp药泵的抑制作用。方法:采用超声法制备Pluronic/SWCNT自组装纳米复合物,以水分散性、分散粒径、形态等为指标进行制备工艺优化。以Caco-2细胞为模型,考察其对P-gp底物罗丹明123(R-123)在Caco-2细胞摄取的影响。结果:优化工艺为以10 mg·m L-1Pluronic F127(或F68)为分散剂,采用探头超声分散法,功率为260 W,超声40次(单次超声时间为3 s)。所制备的纳米复合物Pluronic F127/SWCNT-COOH可在不同程度上促进R-123在Caco-2细胞的摄取。结论:不同组成的Pluronic/SWCNTs纳米复合物促进了P-gp底物R-123的小肠跨膜吸收,应该具有一定的P-gp药泵抑制作用,其制备方法科学、简单、稳定性好。

外翻肠囊法研究Pluronic/SWCNTs对P-糖蛋白底物罗丹明123小肠吸收的影响

目的:考察3种Pluronic/SWCNTs载体材料对小肠P-糖蛋白(P-gp)药泵的抑制作用。方法:采用外翻肠囊模型进行肠吸收实验,以P-gp特异性底物罗丹明123(R-123)大鼠肠吸收参数为考察指标,研究Pluronic/SWCNTs对R-123肠吸收的影响。结果:Pluronic/SWCNTs可以显著增加R-123在各肠段的累计吸收量与吸收速率常数,特别是在浓度为5μg·mL-1与10μg·mL-1时作用最明显(P<0.05)。结论:Pluronic/SWCNTs可以通过抑制P-gp药泵作用改善P-gp底物药物的小肠吸收,在口服载药系统的应用中具备很大的潜力。

F127/SWCNTs对P-gp底物在大鼠小肠吸收影响的研究

目的:考察3种F127/SWCNTs载体系统的稳定性及对小肠P-糖蛋白(P-gp)药泵的抑制作用。方法:将F127/SWCNTs稀释至不同浓度后于4℃放置15 d,检测CNTs含量、粒径、Zeta电位等参数的变化;采用大鼠在体单向灌流模型进行肠吸收试验,以P-gp特异性底物罗丹明123(R-123)大鼠回肠段的吸收速率常数(Ka)和表观渗透系数(Papp)为考察指标,评价F127/SWCNTs对R-123肠吸收的影响。结果:储存稳定性和稀释稳定性均表明其中F127/SWCNT-COOH与F127/SWCNT-OH在15 d内4℃放置稳定性良好,无明显沉淀析出,粒径和含量稳定。3种F127/SWCNTs均可在不同程度增加R-123在回肠段的吸收,且具有浓度依赖性。结论:F127/SWCNTs可能通过抑制P-gp药泵作用改善P-gp底物药物的口服生物利用度,为药物特异性口服应用创造独特机会。

First principles study on magnetic and electronic properties with rare-earth atoms doped SWCNTs

The adsorptions of rare-earth （RE） atoms on （6, 0） and （8, 0） single-walled carbon nanotubes （SWCNTs） have been investigated by using the first-principles pseudopotential plane wave method within density functional theory （DFT）. The binding energy, Mulliken charge, magnetic properties, band structure and DOS were calculated and analyzed. Most of RE atoms including Nd, Sm and Eu have a magnetic ground state with a significant magnetic moment. Some electrons transfer between RE-5d, 6s and C-2p orbitals. Owing to the curvature effect, the values of binding energy for RE atoms doped （6, 0） SWCNT are lower than those of the same atoms on （8, 0） SWCNT. The pictures of DOS show that hybridizations between RE-5d, 6s states and C-2p orbitals and between RE-4f and C-2p orbitals appear near the Fermi level. Results indicate that the properties of SWCNTs can be modified by the adsorptions of RE atoms.

Mixed convectional and chemical reactive flow of nanofluid with slanted MHD on moving permeable stretching/shrinking sheet through nonlinear radiation,energy omission

Hybrid nanofluids are remarkable functioning liquids that are intended to reduce the energy loss while maximizing the heat transmission.In the involvement of suction and nonlinear thermal radiation effects,this study attempted to explore the energy transmission features of the inclined magnetohydrodynamic(MHD)stagnation flow of CNTs-hybrid nanofluid across the nonlinear permeable stretching or shrinking sheet.This work also included some noteworthy features like chemical reactions,variable molecular diffusivity,quadratic convection,viscous dissipation,velocity slip and heat omission assessment.Employing appropriate similarity components,the model equations were modified to ODEs and computed by using the HAM technique.The impact of various relevant flow characteristics on movement,heat and concentration profiles was investigated and plotted on a graph.Considering various model factors,the significance of drag friction,heat and mass transfer rate were also computed in tabular and graphical form.This leads to the conclusion that such factors have a considerable impact on the dynamics of fluid as well as other engineering measurements of interest.Furthermore,viscous forces are dominated by increasing the values ofλ_(p),δ_(m)andδ_(q),and as a result,F(ξ)accelerates while the opposite trend is observed for M andφ.The drag friction is boosted by the augmentation M,λ_(p)andφ,but the rate of heat transfer declined.According to our findings,hybrid nanoliquid effects dominate that of ordinary nanofluid in terms of F(ξ),Θ(ξ)andφ(ξ)profiles.The HAM and the numerical technique(shooting method)were found to be in good agreement.

FEM for Blood-Based SWCNTs Flow Through a Circular Cylinder in a Porous Medium with Electromagnetic Radiation

This work aims to study magnetohydrodynamic flow through a circular cylinder in a horizontal position of SWCNTs in blood as a base fluid in the existence of non-linear thermal radiation and heat source/sink.Three kinds of nanoparticles shapes are considered.The study is employed the finite element technique to explore and enhance the influences of essential parameters on temperature profiles and is debated the heat transport within blood injects with SWCNTs and exposes to electromagnetic radiation.The treatment with thermal analysis and heat transfer rate being a better substitute more than surgery and chemotherapy for cancer therapy.Utilizing of nanoparticles thermal features is a mounting area of nanomedicine field because of the probable for purposeful demolition of cancer cells.This remedy is relied on many parameters,including nanofluid thermal conductivity,nanoparticles volume fraction,thermal radiation and power and heat source.The numerical solutions for flow and heat transfer features are assessed for diverse governing parameters values.The obtained results are substantiated against the relevant numerical results in the published researches.Results show that both flow velocity and temperature increase for larger values of thermal radiation,heat source and SWCNTs volume fraction with lamina and cylinder shapes.Also,spherical shape of SWCNTs occurs high disturbances in velocity and temperature distribution in the case of cooled cylinder.

基于SWCNTs的环丙沙星荧光增敏法研究

SWCNTs-PEG-NH2,SWCNTs-2,3-NH2和SWCNTs-3,4-NH2纳米微球可经由单壁碳纳米管(SWCNTs)共价修饰制备.SWCNTs-PEG-NH2,SWCNTs-2,3-NH2和SWCNTs-3,4-NH2纳米微球的结构可由X-射线光电子能谱(XPS)确证.结果表明酰胺化反应成功.环丙沙星(CIP)萃取实验表明,对于SWCNTs-PEG-NH2微球,在pH=4和pH=6得到较好吸附效果,而0.1 mol/L NaOH和1%SDS洗脱剂可得到较好的洗脱效果.对于SWCNTs-2,3-NH2和SWCNTs-3,4-NH2微球,pH=6得到最好的吸附效果,而1%SDS洗脱条件可到最好的洗脱效果.Al3+离子的加入可以敏化环丙沙星的荧光.

基于SWCNT复合硫化镍/氮化镍电极材料的制备及其电化学性能

以单壁碳纳米管(SWCNT)为碳源,氯化镍为金属源,硫脲为氮源和硫源,通过水热和高温热解方法制备N,S-Ni@S@C复合材料,并对复合材料进行物理表征和电化学性能测试。结果表明,SWCNT与硫化镍、氮化镍复合的结构不仅能提高电极材料的电导率,还能提供更多的活性位点供电解质离子插入或脱出,从而显著提高电化学性能。在三电极体系下,N,S-Ni@S@C复合材料具有较高的电压窗口(1.5 V)和优异的充放电能力,在电流密度为1 A·g^(-1)下,N,S-Ni@S@C的比电容可达162.45 F·g^(-1)。其比电容与SWCNT相比提高了2.61倍,与SWCNT和氯化镍复合材料(C@Ni)相比提高了19倍,与SWCNT和硫脲复合材料(C@S@N)相比提高了16倍。此外,以N,S-Ni@S@C复合材料为正极,商业活性炭(YP50F)为负极,组装得到非对称型超级电容器(N,S-Ni@S@C//AC)。该非对称型超级电容器在功率密度为818.78 W·kg^(-1)时,其能量密度可达41.03 W·h·kg^(-1),在电流密度为1.0 A·g^(-1)时,经过5000次连续充放电循环后比电容仍可保持初始比电容的82%。

Interlayer and intralayer co-modified flexible V_(2)CT_(X) MXene@SWCNT films for high-power Li-ion capacitors

As an emerging member of the two-dimensional(2D)material family,V_(2)CT_(X)MXene shows great potential in the application of lithium-ion capacitors(LICs)due to its unique structure and excellent electrical conductivity.However,severe nanosheets stacking and intra-layer transport barriers have limited the further development of V_(2)CT_(X)MXene-based materials.Herein,we prepared Kions and–O functional group co-modified V_(2)CT_(X)MXene(VCT-K)and further incorporated it with single-walled carbon nanotube(SWCNT),obtaining freestanding V_(2)CT_(X)composite films(VCT-K@C)with the 3D conductive network.Significantly,K+ions were introduced into V_(2)CT_(X)MXene to stabilize the interlayer structure and prevent the aggregation of nanosheets,the terminal group of–O was controllably modified on the surface of MXene to improve the Li+ions storage reversible capacities and the SWCNT acted as the bridge between MXene nanosheets to opens up the channels for ion/electron transportation in the longitudinal direction.Benefited from the synergistic effect of VCT-K and SWCNT,the VCT-K@C exhibits superior reversible specific capacities of 671.8 mA h g^(-1)at 0.1 A g^(-1)and 318 mA h g^(-1)at 1.0 A g^(-1).Furthermore,the assembled LICs with VCT-K@C anode coupling activated carbon(AC)cathode deliver an outstanding power density of 19.0 kW kg^(-1)at 67.4 Wh kg^(-1),a high energy density of 140.5 Wh kg^(-1)at 94.8 W kg^(-1)and a stable capacitance retention of 86%after 6000 cycles at 10 A g^(-1).Such unique structures and excellent electrochemical properties are expected to pave the way for the large-scale application in LICs of MXene-based materials.

基于氯盐掺杂的单壁碳纳米管室温气体传感器

对单壁碳纳米管进行掺杂可以促进特定气体分子与单壁碳纳米管之间的电荷转移,从而提高其响应与选择性。使用氯化铯、氯化金对单壁碳纳米管进行掺杂,并在室温下使用Raman光谱研究了单壁碳纳米管与氯盐之间的界面电荷转移,研制了基于氯盐掺杂的单壁碳纳米管的二氧化氮室温气体传感器。研究结果表明,氯盐掺杂的单壁碳纳米管的D峰和2D峰的位置发生了蓝移。氯化铯掺杂的单壁碳纳米管气体传感器对于体积分数为1×10-6的二氧化氮表现出了高达230%的响应度,以及优异的选择性与可重复性。实验结果表明,氯盐掺杂可以改变单壁碳纳米管的费米能级,从而影响单壁碳纳米管对气体分子的传感性能。