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11.
Yueyue Li Yanan Ban Ruihui Wang Zheng Wang Zhanxian Li Chenjie Fang Mingming Yu 《中国化学快报》2020,31(2):443-446
A ratiometric fluorescent hybrid nanoprobe CDs-1 for arginine(Arg),exhibiting high sensitivity(the limit of detection,LOD,being 6.5×10^-8 mol/L) and excellent selectivity and anti-interference ability,was fabricated through fluorescence resonance energy transfer(FRET) and the electrostatic attraction between positively-charged hemicyanine molecules and negatively-charged carbon dots(CDs).Arg can be quantitatively detected in the concentration range from 6.0×10^-5 mol/L to 2.7×10^-4 mol/L.Further,due to its ability to target mitochondrion and low cytotoxicity,intracellular Arg was succes s fully tracked through ratiometric fluorescence imaging. 相似文献
12.
Yanying Hu Zexin Fang Yongbing Peng Weiqi Yang Xianfeng Ma Jinglong Li Yunqiang Zhao Biao Wang 《中国科学:物理学 力学 天文学(英文版)》2022,(2)
Achieving excellent strength-ductility synergy is a long-lasting research theme for structural materials.However,attempts to enhance strength usually induce a loss of ductility,i.e.,the strength-ductility trade-off.In the present study,the strength-ductility trade-off in duplex stainless steel(DSS)was overcome by developing a bimodal structure using friction stir processing(FSP).The ultimate tensile strength and elongation were improved by 140%and 109%,respectively,compared with those of the asreceived materials.Plastic deformation and concurrent dynamic recrystallization(DRX)during FSP were responsible for the formation of bimodal structure.Incompatible deformation resulted in the accumulation of dislocations at the phase boundaries,which triggered interpenetrating nucleation between the austenite and ferrite phases during DRX,leading to a bimodal structure.The in situ mechanical responses of the bimodal structure during tensile deformation were investigated by crystal plasticity finite element modeling(CPFEM).The stress field distribution obtained from CPFEM revealed that the simultaneous enhancement of strength and ductility in a bimodal structure could be attributed to the formation of a unique dispersion-strengthened system with the austenite and ferrite phases.It is indicated that the present design of alternating fine austenite and coarse ferrite layers is a promising strategy for optimizing the mechanical properties of DSSs. 相似文献
13.
The magnetic skyrmion transport driven by pure voltage-induced strain gradient is proposed and studied via micromagnetic simulation. Through combining the skyrmion with multiferroic heterojunction, a voltage-induced uniaxial strain gradient is adjusted to move skyrmions. In the system, a pair of short-circuited trapezoidal top electrodes can generate the symmetric strain. Due to the symmetry of strain, the magnetic skyrmion can be driven with a linear motion in the middle of the nanostrip without deviation. We calculate the strain distribution generated by the trapezoidal top electrodes pair, and further investigate the influence of the strain intensity as well as the strain gradient on the skyrmion velocity. Our findings provide a stable and low-energy regulation method for skyrmion transport. 相似文献
14.
Yang Zhang Chao Liu Jiaqi Wang Shoujun Ren Yilin Song Peng Quan Liang Fang 《中国化学快报》2023,34(3):107631-150
The transdermal drug delivery(TDD) shows considerable advantages over other administration pathways.However, conventional enhancing permeation methods face a series of challenges owing to barrier function provided by the skin, of which enhancing abilities either are so strong that it results in toxicity and irritation, or too weak to achieve desirable therapeutical effects. To address these issues, it is an urgent need to develop a novel method to overcome the limitations of current measures. Fo... 相似文献
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16.
A novel method is developed for the direct determination of naphazoline hydrochloride(NAP) and pyridoxine hydrochloride(VB6) in commercial eye drops. By using excitation–emission matrix(EEM)fluorescence coupled with second-order calibration method based on the alternating trilinear decomposition(ATLD) algorithm, the proposed approach can achieve quantitative analysis successfully even in the presence of unknown and uncalibrated interferences. The method shows good linearity for NAP and VB6 with correlation coefficients greater than 0.99. The results were in good agreement with the labeled contents. To further confirm the feasibility and reliability of the proposed method, the same batch samples were analyzed by multiple reaction monitoring(MRM) based on LC–MS/MS method.T-test demonstrated that there are no significant differences between the prediction results of the two methods. The satisfactory results obtained in this work indicate that the use of the second-order calibration method coupled with the EEM is a promising tool for industrial quality control and pharmaceutical analysis due to its advantages of high sensitivity, low-cost and simple implementation. 相似文献
17.
Shuang-Shuang Kong Wei-Kai Liu Xiao-Xia Yu Ya-Lin Li Liu-Zhu Yang Yun Ma Xiao-Yong Fang 《Frontiers of Physics》2023,18(4):43302
Silicon carbide nanosheets (SiCNSs) have a very broad application prospect in the field of new two-dimensional (2D) materials. In this paper, the interlayer interaction mechanism of bilayer SiCNSs (BL-SiCNSs) and its effect on optical properties are studied by first principles. Taking the charge and dipole moment of the layers as parameters, an interlayer coupling model is constructed which is more convenient to control the photoelectric properties. The results show that the stronger the interlayer coupling, the smaller the band gap of BL-SiCNSs. The interlayer coupling also changes the number of absorption peaks and causes the red or blue shift of absorption peaks. The strong interlayer coupling can produce obvious dispersion and regulate the optical transmission properties. The larger the interlayer distance, the smaller the permittivity in the vertical direction. However, the permittivity of the parallel direction is negative in the range of 150-300 nm, showing obvious metallicity. It is expected that the results will provide a meaningful theoretical basis for further study of SiCNSs optoelectronic devices. 相似文献
18.
Ying-Dong Nie 《中国物理 B》2023,32(1):18702-018702
Owing to the good adjustability and the strong near-field enhancement, surface plasmons are widely used in optical force trap, thus the optical force trap can achieve excellent performance. Here, we use the Laguerre-Gaussian beam and a plasmonic gold ring to separate enantiomers by the chiral optical force. Along with the radial optical force that traps the particles, there is also a chirality-sign-sensitive lateral force arising from the optical spin angular momentum, which is caused by the interaction between optical orbit angular momentum and gold ring structure. By selecting a specific incident wavelength, the strong angular scattering and non-chiral related azimuthal optical force can be suppressed. Thus the chiral related azimuthal optical force can induce an opposite orbital rotation of the trapped particles with chirality of different sign near the gold ring. This work proposes an effective approach for catchingand separating chiral enantiomers. 相似文献
19.
Photosensitizers that can target and accumulate in mitochondria are expected to achieve good therapeutic effects in photodynamic therapy,as mitochondria are the energy generation factory in cells.Herein,we designed and synthesized a novel mitochondrion-targeting photosensitizer TPC-Py with aggregation-induced emission characteristics for image-guided photodynamic therapy.TPC-Py possessed an efficient production of 1O2,with a quantum yield of 11.65%,upon mild white light irradiation(6 mW/cm2).TPC-Py exhibited good biocompatibility under dark condition,but showed remarkable cytotoxicity towards human cervical carcinoma(HeLa)cells with a half maximal inhibitory concentration(IC50)of 3.2μmol/L when exposed to white light irradiation(14.4 J/cm2).In addition,the Stokes shift of TPC-Py was as high as 150 nm,so that it could prevent self-absorption and increase the signal-to-noise ratio of fluorescence imaging.The excellent performance of TPC-Py makes it a promising candidate in imaging-guided clinical PDT for cancer in the near future. 相似文献
20.
不同结构的分子筛在1-丁烯中催化裂解性能的研究 总被引:3,自引:3,他引:0
我们合成了不同Si含量的SAPO-18,并且利用了XRD、SEM、NH3-TPD进行了表征分析.利用微反固定床反应器评价了代表不同结构的H-ZSM-5(MFI)、H-Beta(* BEA)、SAPO-18 (AEI)系列分子筛的丁烯催化裂解性能.实验结果表明分子筛的结构和酸性对反应结果都有明显影响,分子筛酸量的增加提高了1-丁烯的转化率,但酸量过高会引发氢转移、芳构化副反应,从而降低丙烯的选择性;分子筛孔口大小、孔道结构决定了可以获得的最高丙烯选择性.具有八元环孔口、笼形结构特点的SAPO-18-0.8在线时间20 min时1-丁烯裂解中转化率为60.7%,获得的丙烯选择性达到59.1%. 相似文献