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51.
Spatiotemporally coupled tumor phototheranostic platforms offer a flexible and precise system that takes the biological interaction between tumors and photoactive agents into consideration for optimizing treatment, which is highly consistent with precision medicine. However, the fabrication of monocomponent-based photoactive agents applicable to multifold imaging techniques and multiple therapies in a facile way remains challenging. In this study, we developed simple phthalocyanine–peptide (PF) conjugate-based monocomponent nanoparticles with spatiotemporally coupled photoactivity for adaptive tumor theranostics. The self-assembled PF nanoparticles possess well-defined spherical nanostructures and excellent colloidal stability along with supramolecular photothermal effects. Importantly, the PF nanoparticles showed switchable photoactivity triggered by their interactions with the cell membrane, which enables an adaptive transformation from photothermal therapy (PTT) and photoacoustic imaging (PAI) to photodynamic therapy (PDT) and corresponding fluorescence imaging (FI). Theranostic modalities are integrated in a spatiotemporally coupled manner, providing a facile, biocompatible and effective route for localized tumor phototherapy. This study offers a flexible and versatile strategy to integrate multiple theranostic modalities into a single component so that it can realize its full potential and thereby amplify its therapeutic efficacy, creating promising opportunities for the design of theranostics and further highlighting their clinical prospects to the diagnosis and treatment of cancers.  相似文献   
52.
分次可除模     
对于G—分次环R,我们证明如下结论:(1)若R是分次正则环,则R上的任一分次左R—模都是分次可除模;(2)若R分次非退化且M是分次可除左R—模,则Me是可除左Re—模;(3)若G是有序群,M是可除左R—模,则M~和M~是分次可除左R—模,其中M为分次左R—模N的子模  相似文献   
53.
介绍定量构效关系及其常用研究方法.叙述了化学计量学在我国近年来的发展,以及定量构效关系作为一门新兴的研究手段对现代化学尤其是化学计量学的发展所起的推动作用.  相似文献   
54.
Copper phthalocyanine (CuPc) thin-film transistors (TFTs) have been fabricated using spin-coated polymeric gate insulators, including polymethyl methacrylate (PMMA) and a novel poly(methylmethacrylate-co-glycidylmethacrylate) (P(MMA-co-GMA)). These devices behaved fairly well and showed satisfactory p-type electrical characteristics. The transistor with P(MMA-co-GMA) gate insulator showed higher field-effect mobility, μFET = 1.22 × 10−2 cm2/V s, larger on/off current ratio, Ion/Ioff = 7 × 103 and lower threshold voltage, VT = −8 V, compared with the transistor with PMMA gate insulator (μFET = 5.89 × 10−3 cm2/V s, Ion/Ioff = 2 × 103 and VT = −15 V). The higher mobility of CuPc on P(MMA-co-GMA) was attributed to better ordering and enhanced crystallinity within the CuPc film and the better CuPc/P(MMA-co-GMA) interface, as observed by X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurements. The correlation between the structural properties and the device performance of CuPc films grown on different polymeric gate insulators is discussed.  相似文献   
55.
We demonstrate the near-infrared (NIR) organic light-emitting devices (OLEDs) based on copper hexade-cafluorophthalocyanine (CuPcF16) doped into 2,2,2”-(1,3,5-benzenetriyl)tris-[1-phenyl-1H-benzimidazole] (TPBI). The device structure is ITO/ NPB/ TPBI:CuPcF16/BCP/Alq3/Al. Room-temperature electro- luminescence is observed at about 1106 nm due to transitions from the first excited triplet state to the ground state (T1-S0) of CuPcF16. The result indicates that FSrster and Dexter energy transfers play a minor role in these devices, while the direct charge trapping is the dominant mechanism. The absorption spectra of CuPeF16 solution in pyridine and vacuum sublimed films on quartz have also been investigated.  相似文献   
56.
张敬东  汪风珍 《电化学》1996,2(3):343-345
烯丙醇电还原自由基中间产物的ESR研究张敬东,旷亚非,黄树坤,谢乃贤(湖南大学化学化工系,长沙410082)汪风珍,陈德文(中南工业大学测试中心,长沙410083)(中国科学院化学研究所,北京100080)Horanyi[1]、陈剑[2]等人对酸性水...  相似文献   
57.
Singlet-oxygen (1O2) was generated in the gas phase by heterogeneous photosensitization and bubbled into suspensions of phosphatidylcholine (PC) liposomes. Lipid peroxidation and membrane lysis were observed, and were dependent on the 1O2 concentration and the degree of unsaturation of the liposome. An analysis based on large target diffusion theory indicates that approximately 5000, 2800, and 1600 interactions were required for the lysis of large dioleoylPC, dilinoleoylPC and dilinolenoylPC liposomes, respectively.  相似文献   
58.
A new method of growing single crystal for β-form copper phthalocyanine (CuPc) is presented in this paper. Melted anthracene was used as solvent of CuPc. The method, vaporizing the solvent using an automatic exaltation machine, was employed to grow CuPc single crystals. The needle-like single crystals of CuPc up to 11.6 mm in length were obtained by applying this method. The influences of different temperatures, exaltation speeds and concentrations on the single crystals growth were also discussed. The method was called exaltation–evaporation growth method.  相似文献   
59.
Various improvements in flow-injection systems involving on-line separation and preconcentration by gas diffusion, ion-exchange and liquid—liquid extraction are reviewed and their merits are discussed. On-line preconcentration systems based on gas diffusion are described for the spectrophotometric determination of cyanide, fluoride and ammonia. Different gas/liquid separation devices for hydride-generation and cold-vapour atomic absorption spectrometry (a.a.s.) are compared. Systems are outlined for on-line column preconcentration of cobalt, nickel, vanadium, beryllium and cerium for inductively-coupled plasma/atomic emission spectrometry, and for combinations of column preconcentration with hydride-generation and cold-vapour a.a.s for the determination of ultratrace selenium and mercury. An on-line liquid—liquid extraction/flame a.a.s. system capable of achieving 60-fold enhancement for lead is reported; the limit of detection is 0.02 μg ml?.  相似文献   
60.
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