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901.
The crystal structures of double perovskite BaLaMRuO6 (M=Mg, Zn) obtained from the refinements on both X-ray and neutron diffraction data, different from those reported previously that used either X-ray or neutron diffraction data alone, are reported. The room temperature X-ray and neutron data were refined with a model in the tetragonal space group I4/m (a=5.6230(4), c=7.964(1) Å, V=251.81(4) Å3 for M=Mg; a=5.6521(3), c=7.9987(9) Å, V=255.53(3) Å3 for M=Zn). The low-temperature neutron diffraction data of the two compounds are also refined in the same space group (a=5.6156(4), c=7.953(1) Å, V=250.80(4) Å3 for M=Mg at 13 K; a=5.6418(4), c=7.981(1) Å, V=254.03(4) Å3 for M=Zn at 10 K). Both compounds show almost complete ordering of B-site atoms (M/Ru). For both compounds, the low-temperature neutron diffraction data below about 20 K showed magnetic diffraction peaks that could be accounted for with a Type I antiferromagnetic ordering of Ru spins in an atomically ordered double perovskite structure. These compounds showed discrepancies between field cooled and zero field cooled magnetization data below the antiferromagnetic ordering temperatures.  相似文献   
902.
903.
Fibrin, one of the components of the extracellular matrix (ECM), acts as a transport barrier within the core of tumors by constricting the blood vessels and forming clots, leading to poor intratumoral distribution of anticancer drugs. Our group previously developed a microplasmin-based thrombolytic ferritin nanocage that efficiently targets and dissolves clots without causing systemic fibrinolysis or disrupting hemostatic clots. We hypothesized that the thrombolytic nanocage-mediated degradation of fibrin clots in the tumor ECM can lead to enhanced intratumoral drug delivery, especially for nanosized anticancer drugs. Fibrin clot deposition worsens after surgery and chemotherapy, further hindering drug delivery. Moreover, the risk of venous thromboembolism (VTE) also increases. Here, we used thrombolytic nanocages with multivalent clot-targeting peptides and fibrin degradation enzymes, such as microplasmin, to dissolve fibrin in the tumor microenvironment and named them fibrinolytic nanocages (FNCs). These FNCs target tumor clots specifically and effectively. FNCs efficiently dissolve fibrin clots inside of the tumor vessels, suggesting that they can mitigate the risk of VTE in cancer patients. Coadministration of FNC and doxorubicin led to improved chemotherapeutic activity in a syngeneic mouse melanoma model. Furthermore, the FNCs increased the distribution of Doxil/doxorubicin nanoparticles within mouse tumors. These results suggest that fibrinolytic cotherapy might help improve the therapeutic efficacy of anticancer nanomedicines. Thus, microplasmin-based fibrinolytic nanocages are promising candidates for this strategy due to their hemostatic safety and ability to home in on the tumor.Subject terms: Drug development, Drug delivery  相似文献   
904.
905.
The BAB‐type triblock copolymers composed of a central poly(ethylene oxide) (PEO, nPEO = 1 000) block and two poly[(D ,L ‐lactic acid)‐co‐(glycolic acid)] end blocks with molecular weights between 900 and 1 600 exhibited an interesting phase transition behavior. The copolymer aqueous solution can form micelles with PLGA loops in the core and a PEO shell and groups of micelles because of bridging between micelles caused by the PLGA blocks with raising temperature. A possible micellar gelation mechanism was suggested.  相似文献   
906.
Poly(silylenevinylene(bi)phenylenevinylene)s were synthesized by chloroplatinic acid-catalyzed hydrosilylation polymerization between α,ω-diethynylarenes and methylphenylsilane or diphenylsilane. The polymer structure was dependent on the substituent size of silane reagent. Poly(silylenevinylenephenylenevinylene)s showed fluorescence emission in the blue region. Optical and thermal properties of the polymers were extensively investigated. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2933–2940, 1999  相似文献   
907.
Pyridine‐catalyzed reactions of methyldichlorosilane with bis(trimethylsilyl)carbodiimide afford a dichlorosilane‐derived anhydrous sol–­gel material. Both trimethylchlorosilane formation and Si–H disproportionation act as crosslinking mechanisms. The dried gels form amorphous or crystalline materials, depending on the sample history. The xerogels gave Si/C/N ceramics when pyrolyzed at 1200 °C. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
908.
Journal of Solid State Electrochemistry - The rational design of low-cost electrode materials with superior redox activity and high electrochemical conductivity has attracted extensive interest for...  相似文献   
909.
Erbium (Er3+) doped LiNbO3 single crystal thin films have been grown LiNbO3 (001) substrate by the liquid phase epitaxy method. The crystallinity was determined by high‐resolution X‐ray diffraction. The lattice mismatch between Er3+ doped LiNbO3 films and LiNbO3 (001) substrate was investigated by X‐ray rocking curve analysis. Also we studied the structural characteristics of Er3+ doped LiNbO3 films and surface morphology dependent on the film thickness.  相似文献   
910.
A blend of a newly synthesized polyfluorene(PDHBF) and polyvinylcarbazole(PVK) exhibits a photoluminescence(PL) emission spectrum of PDHBF without an increase in the PL intensity on photoexcitation at 340 nm, the UV-visible absorption maximum of PVK, despite of a substantial spectrum overlap. However, the indirect photoexcitation of the blend suppresses the secondary emission of the PL with the maximum at 520 nm. The chromophores generating the secondary emission are formed when the chromophores are photoexcited above the critical energy level of an excited state. The chromophores formed by the energy transfer have energy lower than the critical energy and fail to form the excimers. A low temperature PL study of the blend in a cryogenic chamber proves that the energy transfer in the system takes place mainly between the excimers of PVK generated by the partially eclipsed dimeric states of two carbazole units and the fluorophores of PDHBF.  相似文献   
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