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991.
D. P. Chiang C. H. Peng J. K. Mei I. M. Jiang S. C. Lin Y. C. Chen H. T. Liu Y. F. Chen W. S. Tse 《Journal of Raman spectroscopy : JRS》2008,39(3):344-348
Raman studies of crystalline iron perchlorate hexahydrate (Fe(ClO4)2·6H2O) in the region of lattice and anion internal modes were carried out in the temperature range 80–385 K. The temperature‐dependent Raman results are consistent with those from previous works, showing that two phase transitions occur around 336 and 245 K. The transition at 336 K may be considered as an order–disorder transformation, while the one at 245 K is associated with the configurational disorder of the tetrahedron of the perchlorate ions. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
992.
Yuanyuan Li Jie Sun Li Wang Peng Zhan Zhishen Cao Zhenlin Wang 《Applied Physics A: Materials Science & Processing》2008,92(2):291-294
A sensor based on surface plasmon resonance (SPR) of plasmonic crystals fabricated via a colloidal-crystal-assisted templating
method is studied. Plasmonic crystals are prepared by depositing a thin gold (Au) layer onto a two-dimensional array of polystyrene
spheres self-assembled on a quartz substrate. The enhanced transmission as a result of the SPR of Au plasmonic crystals, which
are immersed in different ambient liquids, are measured and compared with that of polystyrene (PS) microsphere templates of
different sizes, both before and after removal of Au nanoprisms formed on the quartz substrate through pores among the spheres.
It is found that the measured sensitivities exhibit a linear dependence on the refractive index of the surrounding medium
and are linked to coupling effects between SPRs on the corrugated Au film and nanoislands. The feasibility of the SPR system
in molecular monolayer detection is further demonstrated through a formation of alkanethiolate self-assembled monolayers on
the Au film surface, which causes a 4 nm red-shift of the main SPR.
PACS 07.07.Df; 73.20.Mf; 78.66.-w; 81.16.Dn 相似文献
993.
The sensitive and selective detection of nucleic acids is important for basic research and many applied fields. Herein, a novel green DEAB-TO-1 was designed and synthesized. DEAB-TO-1 shows significant fluorescence enhancement (800-fold) when bound to ctDNA and a distinct selectivity for dsDNA over RNA (5.9 times). Moreover, the limit of detection is 0.57 ng/mL. It is live-cell-permeant DNA intecalator, indicating a promising candidate for nucleus-specific imaging and a good counter-stain compatibility with other dyes. 相似文献
994.
Peng Jiehui Zhan Pei Deng Runkang Zhang Yanli Xie Xinyuan 《Research on Chemical Intermediates》2019,45(9):4637-4651
Research on Chemical Intermediates - In this paper, a one-pot and sustainable method for the preparation of Ag/ZnO nanocomposites in green polyethylene glycol-200 (PEG-200) was reported with silver... 相似文献
995.
996.
Zhang Yi Huang Peng Long Mei Liu Song Yang Huaming Yuan Shuwen Chang Shi 《中国科学:化学(英文版)》2019,62(1):58-61
An innovative cancer therapy strategy regarding the interface engineering of kaolinite has been designed. The exposed silanol group facilitates more guest species with high dispersion on the supports. Mn_3O_4 magnetic nanoparticles are uniformly distributed on external surfaces of the Kaolin_(C12N)with the Al–O–Mn bond for the detection of the tumor microenvironment by T1-MRI; Doxorubicin(DOX) are loaded in the interlayer space with the electrostatic interaction for chemo-treating; and KI is coated on the outer layer of the nanocomposites based on the electrostatic interaction for thyroid cancer targeting. The synergetic effects and the treatment mechanism enhanced by the interface engineering, KI@DOX-Mn_3O_4-Kaolin_(C12N)can cause remarkably low cell viability(57%, 200 μg/mL), tumor shrinking(75%, 20 μg/kg), and accumulation into the tumor tissues. The novel kaolinite based drug delivery system is expected to incorporate imaging diagnosis, targeted therapy and drug delivery into one single system for postoperative residual thyroid cancer treatment and observation for metastasis of focal area. 相似文献
997.
Nonlinear Dynamics - Distribution entropy has been proved to reveal stability for short time series and to distinguish different classes of series by complexity. However, there still exists some... 相似文献
998.
Nonlinear Dynamics - In this paper, a torsion–translational quasi-zero-stiffness (TT QZS) isolator with convex ball–roller mechanisms was proposed to attenuate the torsion and... 相似文献
999.
Nonlinear Dynamics - As an unmanned system, the multirotor has gained widespread attention in practical aviation engineering, because of its ease of use, reliability and maintainability. From the... 相似文献
1000.
Dr. Xiang Hao Kaixiang Yang Hairong Wang Prof. Feng Peng Prof. Haiyang Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(11):4344-4349
Non-Newtonian fluids are ubiquitous in daily life and industrial applications. Herein, we report an intelligent fluidic system integrating two distinct non-Newtonian rheological properties mediated by an autocatalytic enzyme reaction. Associative polyelectrolytes bearing a small amount of ionic and alkyl groups are engineered: by carefully balancing the charge density and the hydrophobic effect, the polymer solutions demonstrate a unique shear thickening property at low pH while shear thinning at high pH. The urea-urease clock reaction is utilized to program a feedback-induced pH change, leading to a strong upturn of the nonlinear viscoelastic properties. As long as the chemical fuel is supplied, two distinct non-Newtonian states can be achieved with a tunable lifetime span. As a proof of concept, we demonstrate how the physical energy-driven nonequilibrium properties can be manipulated by a chemical-fueled process. 相似文献