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81.
PbTiO3 thin films were successfully deposited on the LaNiO3 (LNO) substrates by the liquid-phase deposition (LPD) method and post-annealing at various temperatures. The structure, morphology and composition of the films were investigated by some analytical techniques. The as-deposited films are amorphous and composed of densely packed spherical particles. The films with the grain size of 180 nm start to decompose and crystallize into perovskite structure at 450 °C and show a perovskite single phase with tetragonal structure after annealing at 650 °C. X-ray photoelectron spectroscopy (XPS) analysis reveals that the as-deposited film contains fluorine and carbon as major impurities. Fluorine could be completely eliminated by annealing at 650 °C in air. 相似文献
82.
Yunn-Hwa Ma Ya-Wun Hsu Yeu-Jhy Chang Mu-Yi Hua Jyh-Ping Chen Tony Wu 《Journal of magnetism and magnetic materials》2007
Targeted delivery of thrombolytic drug to the site of emboli exhibits potential to greatly reduce hemorrhagic side effect. A rat embolic model with an easy access of a magnet was established for study of the efficacy of magnetic drug targeting. In anesthetized rats, a whole blood clot produced in vitro was injected from the right iliac artery and lodged in the left iliac artery. Intra-arterial infusion of recombinant tissue plasminogen activator (rt-PA) thereafter significantly reversed the iliac flow within 15 min. Placement of an NdFeB magnet above the left iliac artery caused magnetic nanoparticle retention against hemodynamic dragging force in the presence and absence of the clot. Our results suggest the feasibility of this rat embolic model for the study of magnetic targeted delivery of thrombolytic drugs. 相似文献
83.
Wen.-C. Chiang J.G. Lin K.H. Hsu D.S. Hussey D.V. Baxter 《Journal of magnetism and magnetic materials》2006
We investigate Co/Nb multilayers to explore the spontaneous π-phase shift between the superconducting (SC) layers, which is attributed for causing the non-monotonic change of the SC transition temperature (Tc) with the ferromagnetic (FM) layer thickness (tFM) in several FM/SC multilayered systems. The issue of interfacial roughness is also explored by growing Co/Nb multilayers at various sputtering pressures. Transport measurements show a non-monotonic dependence of Tc on tFM, and this dependence is insensitive to the structural variation present in the samples, as measured by X-ray scattering. 相似文献
84.
Chih-Kai Huang Chia-Yin Chen Jin-Lin Han Chii-Chang Chen Meng-Dan Jiang Jen-Sung Hsu Chia-Hua Chan Kuo-Huang Hsieh 《Journal of nanoparticle research》2010,12(1):199-207
The silver nanoparticles (Ag NPs) have been immobilized onto silica microspheres through the adsorption and subsequent reduction
of Ag+ ions on the surfaces of the silica microspheres. The neat silica microspheres that acted as the core materials were prepared
through sol–gel processing; their surfaces were then functionalized using 3-mercaptopropyltrimethoxysilane (MPTMS). The major
aims of this study were to immobilize differently sized Ag particles onto the silica microspheres and to understand the mechanism
of formation of the Ag nano-coatings through the self-assembly/adsorption behavior of Ag NPs/Ag+ ions on the silica spheres. The obtained Ag NP/silica microsphere conglomerates were characterized by field-emission scanning
electron microscopy (FE-SEM), transmission electron microscopy (TEM), and energy-dispersive spectroscopy (EDS). Their electromagnetic
wave shielding effectiveness were also tested and studied. The average particle size of the obtained Ag NPs on the silica
microsphere was found that could be controllable (from 2.9 to 51.5 nm) by adjusting the ratio of MPTMS/TEOS and the amount
of AgNO3. 相似文献
85.
By use of a near-field scanning optical microscope in collection mode, multimode interference was directly measured in an annealed proton-exchanged LiNbO3 waveguide. Periodic transitions from a single-peaked Gaussianlike intensity distribution to a double-peaked intensity distribution were observed. The intensity distribution along the waveguide was calculated, and the results agree well with the experimental observation. 相似文献
86.
Fabrication and comparison of PMN-PT single crystal, PZT and PZT-based 1-3 composite ultrasonic transducers for NDE applications 总被引:2,自引:0,他引:2
Ki-Bok Kim David K. Hsu Bongyoung Ahn Young-Gil Kim Daniel J. Barnard 《Ultrasonics》2010,50(8):790-797
This paper describes fabrication and comparison of PMN-PT single crystal, PZT, and PZT-based 1-3 composite ultrasonic transducers for NDE applications. As a front matching layer between test material (Austenite stainless steel, SUS316) and piezoelectric materials, alumina ceramics was selected. The appropriate acoustic impedance of the backing materials for each transducer was determined based on the results of KLM model simulation. Prototype ultrasonic transducers with the center frequencies of approximately 2.25 and 5 MHz for contact measurement were fabricated and compared to each other. The PMN-PT single crystal ultrasonic transducer shows considerably improved performance in sensitivity over the PZT and PZT-based 1-3 composite ultrasonic transducers. 相似文献
87.
The absorption spectra and the characteristic emission and excitation spectra of CsI:Na bulk crystals at temperatures between 300 K and 4.2 K are reported. Localized exciton energies were calculated by considering a Born-Haber cycle. The results were compared with the experimental results and the origins of the absorption bands were identified. The characteristic emission spectrum consists of two bands, one peaking around 4200 Å, the other around 3800 Å. The corresponding excitation spectra show that this emission is due to the recombination of a relaxed exciton which was created by transferring an electron from an iodine ion to a substitutional sodium ion in an otherwise perfect CsI lattice. 相似文献
88.
Kuan-Yu Lin Chak Hin Lam Xin-Hui Lin Jung-I Hsu Syuan-Yun Fan Dr. Nitesh K. Gupta Yu-Chun Lin Boon Khoon Tee Jui-Ping Li Dr. Jen-Kun Chen Prof. Dr. Kui-Thong Tan 《化学:亚洲杂志》2021,16(8):937-948
To date, various affinity-based protein labeling probes have been developed and applied in biological research to modify endogenous proteins in cell lysates and on the cell surface. However, the reactive groups on the labeling probes are also the cause of probe instability and nonselective labeling in a more complex environment, e. g., intracellular and in vivo. Here, we show that labeling probes composed of a sterically stabilized difluorophenyl pivalate can achieve efficient and selective labeling of endogenous proteins on the cell surface, inside living cells and in vivo. As compared with the existing protein labeling probes, probes with the difluorophenyl pivalate exhibit several advantages, including long-term stability in stock solutions, resistance to enzymatic hydrolysis and can be customized easily with diverse fluorophores and protein ligands. With this probe design, endogenous hypoxia biomarker in living cells and nude mice were successfully labeled and validated by in vivo, ex vivo, and immunohistochemistry imaging. 相似文献
89.
90.
Hsu WL Li YC Chen HL Liou W Jeng US Lin HK Liu WL Hsu CS 《Langmuir : the ACS journal of surfaces and colloids》2006,22(18):7521-7527
Polyanionic DNA interacts with cationic amphiphiles to form electrostatic complexes exhibiting rich self-assembled structures. This type of complex has been considered as a nonviral carrier in gene therapy and as a template for nanostructure construction. Here we report a thermally-induced phase transition of the complexes of DNA with the mixtures of a cationic surfactant, dodecyltrimethyl bromide (DTAB), and a neutral lipid, dioleoylphosphatidylethanolamine (DOPE), in fully hydrated state. An order-order transition between a multilamellar (L(c)alpha) phase and an inverted hexagonal (H(c)II) phase was found to occur with the transition temperature adjustable by the DTAB-to-DNA base pair molar ratio (x) and DOPE-to-DTAB molar ratio (m). The stability of the L(c)alpha phase was enhanced at lower m and x, as the L(c)alpha-to-H(c)II transition temperature increased with the decreases of these two parameters. The suppression of -to- transition at lower x was attributed to the lower entropic gain from the counterion release due to the presence of uncomplexed DNA in the bulk solution. 相似文献