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oe1(光电查) - 科学论文

17 条数据
?? 中文(中国)
  • Perfluorinated porphyrazines

    摘要: Nucleophilic substitution of fluorine atoms in the phenyl rings by alkoxy groups was performed in perfluorosubstituted zinc(II) octaphenylporphyrazine [ZnPAF40]. Up to 12 fluorine atoms are substituted in the reaction with sodium butoxide in boiling butanol leading to the formation of [ZnPAF40–n(OBu)n] (n = 6—12). Up to eight monosaccharide groups are introduced in the reaction with 1,2:3,4-di-O-isopropylidene-α-D-galactopyranose (Gal′) in toluene in the presence of sodium hydride leading to the formation of [ZnPaF(40–n)(Gal′)n] (n = 6—8). It was possible to obtain a water-soluble glycoconjugated zinc(II) porphyrazine [ZnPaF(40–n)(Gal)n] after removal of the isopropylidene protecting groups by treatment with trifluoroacetic acid. Substitution products are characterized by electron absorption spectroscopy, NMR spectroscopy, and mass spectrometry. Substituting the fluorine atoms with monosaccharide residues leads to an increase in the fluorescence quantum yield from ФF = 0.19 for [ZnPAF40] to 0.29 for [ZnPA(Gal′)nF40–n] (n = 6—8).

    关键词: galactose,perfluorinated porphyrazines,water soluble porphyrazines,nucleophilic aromatic substitution

    更新于2025-11-19 16:46:39

  • S, N co-doped graphene quantum dots-induced ascorbic acid fluorescent sensor: Design, characterization and performance

    摘要: In this work, new detection route for ascorbic acid was designed. First, highly luminescent sulfur and nitrogen doped graphene quantum dots (S,N-GQDs) were prepared via simple hydrothermal method using citric acid and thiourea as the C, N and S sources respectively. The prepared S,N-GQDs are characterized by XRD, HRTEM, FTIR, EDS and PL. Investigations showed that prepared S,N-GQDs have a good photostability and excitation-dependent emission fluorescence. Prepared S,N-GQDs showed maximum excitation wavelength and emission wavelength at 400 and 462nm, respectively. In the following, prepared S,N-GQDs were applied as a photoluminescence probe for detection of ascorbic acid (AA). The designed sensor was based on “off-on” detection mode. The developed sensor had a linear response to AA over a concentration range of 10-500μM with a detection limit of 1.2μM. The regression equation is Y = 0.0014 X+1.2036, where Y and X denote the fluorescence peak intensity and AA concentration, respectively.

    关键词: Graphene quantum dots,Quantum confinement,Fluorescence sensor,Nanostructures,Water-soluble vitamin,Quenching

    更新于2025-11-14 15:32:45

  • Water-soluble titanium-oxides: Complexes, clusters and nanocrystals

    摘要: The water-soluble titanium-oxide structures covered in this review span a continuum from molecular clusters to colloidal nanocrystals. Here, a deliberate distinction is made between titanium clusters and nanoparticles with organic ligands, soluble in organic solvents, and related structures prepared and soluble in water. This distinction is made in response to rapid developments in three areas covered in this article: small titanium-oxide clusters prepared at low pH values in water, heterpolytungstate macroanions with high-nuclearity titanium-oxide cores, and polyoxometalate complexes of anatase-phase TiO2. The latter nanostructures occupy a unique position between polyoxometalate macroanions and traditional colloidal TiO2. As such, the progressively larger water-soluble titanium-oxide structures covered in the three main sections of this review establish a continuum that begins to blur the longstanding divide between molecular and colloid science.

    关键词: Polyoxometalates,Titanium oxide,Water soluble,Clusters,Nanocrystals

    更新于2025-09-23 15:23:52

  • A promising family of fluorescent water-soluble aza-BODIPY dyes for in vivo molecular imaging

    摘要: A new family of water-soluble and bioconjugatable aza-BODIPY fluorophores was designed and synthesized using a boron-functionalization strategy. These dissymmetric bis-ammonium aza-BODIPY dyes present optimal properties for a fluorescent probe, i.e. they are highly water-soluble, very stable in physiological medium, they do not aggregate in PBS, possess high quantum yield and finally they can be easily bioconjugated to antibodies. Preliminary in vitro and in vivo studies were performed for one of these fluorophores to image PD-L1 (Programmed Death-Ligand 1), highlighting the high potential of these new probes for future in vivo optical imaging studies.

    关键词: molecular Imaging,Fluorescent probes,boron functionalization,aza-BODIPY,Water-soluble fluorophores

    更新于2025-09-23 15:23:52

  • Unprecedented Multicolor Photoluminescence from Hyperbranched Poly(amino ester)s

    摘要: A novel kind of water-soluble fluorescent hyperbranched poly(amino ester) (PAE) is prepared through a one-pot polycondensation reaction of citric acid (CA) and N-methyldiethanolamine (NMDEA). The PAE exhibits enhanced and red-shift fluorescence with increasing solution concentration, showing distinct aggregation-induced emission character. Interestingly, the resulting PAE exhibits tunable photoluminescence from blue, cyan, and green to red irradiated by altering the excitation wavelengths. Such unique emission of non-conjugated PAE is attributed to the clustering of ester and tertiary amine groups derived from PAE self-assembly aggregates. Moreover, the fluorescence of PAE is very sensitive to Fe3+ ions. The facile preparation and unique optical features make PAE potentially useful in numerous applications such as multicolor cellular imaging, Fe3+ ions probe, and light-emitting diodes.

    关键词: aggregation-induced emission,poly(amino ester)s,water-soluble polymers,hyperbranched,fluorescence

    更新于2025-09-23 15:23:52

  • The design and properties study of a novel styryl-pyridinium-based water-soluble fluorescent copolymer as tracing agent

    摘要: A water-soluble ?uorescent copolymer poly(acrylamide-acrylic acid-styrene pyridinium) (PAAS) for detecting polymer concentration in real time was synthesized via micellar free-radical polymerization by acrylamide, acrylic acid, and styryl-pyridinium salt derivative (SP-4). The special Donor-π-Acceptor unit and ionic structure of SP-4 endued the copolymer with excellent ?uorescent properties and remarkable water solubility. The ?uorescent copolymer was fully characterized by Fourier transform infrared, 1H nuclear magnetic resonance, thermogravimetry, Ubbelohde viscosity, ultraviolet–visible spectroscopy, and ?uorescence measurements. Furthermore, the ?uorescence intensity and the concentration of PAAS were veri?ed to have ideal linear relationship with a correlation coef?cient up to 0.9993, indicating that the copolymer’s concentration can be easily measured by detecting its ?uorescence intensity. Most importantly, the introduction of water-soluble ?uorescent monomer SP-4 endowed the PAAS with good ?uorescent stability in a wide range of temperature, pH, and brine concentrations. This study demonstrated that the ?uorescent copolymer PAAS exhibits great potential application in detecting polymer concentration in various environments.

    关键词: ?uorescent polymer,water-soluble,tracing agent

    更新于2025-09-23 15:21:21

  • Versatile, Aqueous Soluble C <sub/>2</sub> N Quantum Dots with Enriched Active Edges and Oxygenated Groups

    摘要: C2N has emerged as a new family of promising two-dimensional (2D) layered frameworks in both fundamental studies and potential applications. Transforming bulk C2N into zero-dimensional quantum dots (QDs) could induce unique quantum confinement and edge effects that produce improved or new properties. Despite their appealing potential, C2NQDs remain unexplored, and their intriguing properties and a fundamental understanding of their prominent edge effects are still not well understood. Here, we report the first synthesis of water-soluble C2NQDs via a top-down approach without any foreign stabilizer and exploit their linear/nonlinear optical properties and unique edge-preferential electrocatalytic activity toward polysulfides for versatile applications. The resultant dispersant-free C2NQDs with an average size of sub-5 nm feature rich oxygen-carrying groups and active edges, not only enabling excellent dispersion in water but also creating interesting multifunctionality. They can emit not only blue one-photon luminescence (OPL) under UV excitation but also green two-photon luminescence (TPL), enabling their use as a new fluorescent ink. Interestingly, when C2NQDs are introduced to modify commercial separators, they can function as new metal-free catalysts to boost polysulfide redox kinetics and endow Li-S batteries with excellent cycling stability, high rate capability and large areal capacity (7.0 mA h cm-2) at a high sulfur loading of 8.0 mg cm-2. Detailed theoretical and experimental results indicate that the edge of C2N is more favorable for trapping and catalyzing the polysulfide conversion than the terrace and that the synergy between the active edges and oxygenated groups enriched in C2NQDs remarkably improves polysulfide immobilization and catalytic conversion.

    关键词: fluorescent ink,multifunctionality,C2N quantum dots,Li-S batteries,polysulfide redox kinetics,water-soluble

    更新于2025-09-23 15:19:57

  • Biomemristic Behavior for Water-Soluble Chitosan Blended with Graphene Quantum Dot Nanocomposite

    摘要: Bionanocomposite has promising biomemristic behaviors for data storage inspired by a natural biomaterial matrix. Carboxylated chitosan (CCS), a water-soluble derivative of chitosan avoiding the acidic salt removal, has better biodegradability and bioactivity, and is able to absorb graphene quantum dots (GQDs) employed as charge-trapping centers. In this investigation, biomemristic devices based on water-soluble CCS:GQDs nanocomposites were successfully achieved with the aid of the spin-casting method. The promotion of binary biomemristic behaviors for Ni/CCS:GQDs/indium-tin-oxide (ITO) was evaluated for distinct weight ratios of the chemical components. Fourier transform infrared spectroscopy, Raman spectroscopy (temperature dependence), thermogravimetric analyses and scanning electron microscopy were performed to assess the nature of the CCS:GQDs nanocomposites. The ?tting curves on the experimental data further con?rmed that the conduction mechanism might be attributed to charge trapping–detrapping in the CCS:GQDs nanocomposite ?lm. Advances in water-soluble CCS-based electronic devices would open new avenues in the biocompatibility and integration of high-performance biointegrated electronics.

    关键词: biomemristic behavior,water-soluble CCS:GQDs nanocomposites,CCS-based,binary biomemory

    更新于2025-09-23 15:19:57

  • Photocontrolled Iodine-Mediated Green Reversible-Deactivation Radical Polymerization of Methacrylates: Effect of Water in the Polymerization System

    摘要: Photocontrolled iodine-mediated reversible-deactivation radical polymerization (RDRP) is a facile and highly efficient access to precision polymers. Herein, a facile photocontrolled iodine-mediated green RDRP strategy was successfully established in water by using 2-iodo-2-methylpropionitrile (CP-I) as the initiator and water-soluble functional monomers including poly(ethylene glycol) methyl ether methacrylate (PEGMA), 2-hydroxyethyl methacrylate (HEMA), and 2-hydroxypropyl methacrylate (HPMA) as the model monomers under blue-light-emitting diode (LED) irradiation at room temperature. Well-defined polymers (PPEGMA, PHEMA, PHPMA) with narrow polydispersities (1.09?1.21) were obtained, and amphiphilic block copolymers which can form nanospheres in situ in water (PPEGMA-b-poly(benzyl methacrylate) (PPEGMA-b-PBnMA) and PPEGMA-b-PHPMA) were prepared. To explore the role of water in our polymerization, control experiments were successfully carried out by using oil-soluble monomer methyl methacrylate (MMA) with the help of trace amounts of water. Notably, the green solvent—water—has an additionally positive effect in accelerating the polymerization and makes our polymerization system an environmentally friendly polymerization system. Therefore, this simple strategy conducted in the presence of water enables the green preparation of well-defined water-soluble or water-insoluble polymers and clean synthesis of amphiphilic copolymer nanoparticles in situ.

    关键词: blue-light-emitting diode,water-soluble functional monomers,amphiphilic block copolymers,green solvent,RDRP,Photocontrolled iodine-mediated reversible-deactivation radical polymerization

    更新于2025-09-19 17:13:59

  • Water-soluble ZnO quantum dots modified by (3-aminopropyl)triethoxysilane: The promising fluorescent probe for the selective detection of Cu2+ ion in drinking water

    摘要: Copper, as an essential element in human body, can have adverse impact on environment and healthy individuals if it is excessive. So it is necessary to establish a rapid and effective method for detecting Cu2+. In this work, we describe a method for determination of Cu2+ based on water-soluble ZnO quantum dots (QDs) modified with (3-aminopropyl)triethoxysilane (APTEs). The ZnO QDs functionalized with APTEs (NH2-ZnO QDs) synthesized by a simple sol-gel method and displayed strong yellow-green fluorescence with a peak at 535 nm under 350 nm excitation. High-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, luminescence, and UV-visible absorption spectroscopy were used to characterize the NH2-ZnO QDs. In addition, the emission from NH2-ZnO QDs was selectively quenched upon addition of Cu2+. Therefore, this finding was used to design a fluorescent probe based on NH2-ZnO QDs to detect Cu2+ in water solution, and the linear relationships were 2-20 nM and 1-100 μM respectively, with detection limit for Cu2+ at 1.72 nM (on the basis of 3σ/slope criterion). This fluorescent probe had also been applied in real water sample to testify its availability in drinking water. Furthermore, the quenching mechanism was studied by measurements of UV-visible absorption spectra and fluorescent lifetime of ZnO QDs, which may be attributed to the aggregation induced by Cu2+ and the dynamic quenching existing energy transfer between QDs and Cu2+.

    关键词: Drinking water,Water-soluble,Fluorescent probe,Cu2+ detection,ZnO QDs,Quenching mechanism

    更新于2025-09-16 10:30:52