Visible-light induced electron modulation to improve photoactivities of coral-like Bi2WO6 by coupling SnO2 as a proper energy platform

Lanthanum hydroxycarbonate (LaCO3OH), a kind of fluorescence materials, was less studied in application for photocatalysis. In this paper, LaCO3OH/In(OH)3/In2S3 (LCO/IO/IS) heterostructures were firstly synthesized by a mild two-step hydrothermal method and investigated by various technologies. The activity of as-prepared samples was evaluated by the degradation of Rhodamine B (RhB) under visible light ([Formula: see text][Formula: see text]nm). When the content of LaCO3OH is 15[Formula: see text]mol.% (La/In), the obtained sample exhibits the highest performance, beyond two times as high as that of In(OH)3/In2S3. The improved photodegradation activity might be ascribed to higher adsorption capability and photosensitization of RhB due to proper energy structures of the heterostructures, which prompts the effective separation of electrons and holes. This work extends the application of rear earth salts (lanthanum hydroxycarbonate) for purification of dye waste water.

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Studies of metaphase chromosomes in the scanning transmission x-ray microscope: Image fidelity, radiation damage and specimen preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100129826 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1038-1039

Author(s):

Shawn Williams ◽

Xiaodong Zhang ◽

Susan Lamm ◽

Jack Van’t Hof

Keyword(s):

Visible Light ◽

Radiation Damage ◽

Cross Section ◽

Imaging Techniques ◽

Dose Range ◽

Specimen Preparation ◽

X Rays ◽

Metaphase Chromosomes ◽

X Ray ◽

Scanning Transmission

The Scanning Transmission X-ray Microscope (STXM) is well suited for investigating metaphase chromosome structure. The absorption cross-section of soft x-rays having energies between the carbon and oxygen K edges (284 - 531 eV) is 6 - 9.5 times greater for organic specimens than for water, which permits one to examine unstained, wet biological specimens with resolution superior to that attainable using visible light. The attenuation length of the x-rays is suitable for imaging micron thick specimens without sectioning. This large difference in cross-section yields good specimen contrast, so that fewer soft x-rays than electrons are required to image wet biological specimens at a given resolution. But most imaging techniques delivering better resolution than visible light produce radiation damage. Soft x-rays are known to be very effective in damaging biological specimens. The STXM is constructed to minimize specimen dose, but it is important to measure the actual damage induced as a function of dose in order to determine the dose range within which radiation damage does not compromise image quality.

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Scanning luminescence x-ray microscopy: Progress toward selective staining using microspheres

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168104 ◽

1994 ◽

Vol 52 ◽

pp. 74-75

Author(s):

C. Jacobsen ◽

J. Fu ◽

S. Mayer ◽

Y. Wang ◽

S. Williams

Keyword(s):

Visible Light ◽

Active Sites ◽

Light Emission ◽

Chinese Hamster ◽

Polystyrene Spheres ◽

Good Resistance ◽

X Ray ◽

Selective Staining ◽

Visible Light Emission ◽

Specific Labelling

In scanning luminescence x-ray microscopy (SLXM), a high resolution x-ray probe is used to excite visible light emission (see Figs. 1 and 2). The technique has been developed with a goal of localizing dye-tagged biochemically active sites and structures at 50 nm resolution in thick, hydrated biological specimens. Following our initial efforts, Moronne et al. have begun to develop probes based on biotinylated terbium; we report here our progress towards using microspheres for tagging.Our initial experiments with microspheres were based on commercially-available carboxyl latex spheres which emitted ~ 5 visible light photons per x-ray absorbed, and which showed good resistance to bleaching under x-ray irradiation. Other work (such as that by Guo et al.) has shown that such spheres can be used for a variety of specific labelling applications. Our first efforts have been aimed at labelling ƒ actin in Chinese hamster ovarian (CHO) cells. By using a detergent/fixative protocol to load spheres into cells with permeabilized membranes and preserved morphology, we have succeeded in using commercial dye-loaded, spreptavidin-coated 0.03μm polystyrene spheres linked to biotin phalloidon to label f actin (see Fig. 3).

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Photocatalyst-free decarboxylative aminoalkylation of imidazo[1,2-a]pyridines with N-aryl glycines enabled by visible light

Organic Chemistry Frontiers ◽

10.1039/c9qo00935c ◽

2019 ◽

Vol 6 (21) ◽

pp. 3693-3697 ◽

Cited By ~ 11

Author(s):

Jiu-Jian Ji ◽

Zhi-Qiang Zhu ◽

Li-Jin Xiao ◽

Dong Guo ◽

Xiao Zhu ◽

...

Keyword(s):

Visible Light

A novel, green and efficient visible-light-promoted decarboxylative aminoalkylation reaction of imidazo[1,2-a]pyridines with N-aryl glycines has been described.

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