A non-peptide-based fluorescent probe capable of sensitively visualizing asparagine endopeptidase.

The non-peptide-based fluorescent probe QMC11 is capable of specifically targeting asparagine endopeptidase (AEP) and imaging cellular endogenous AEP. The motion of the probe can be restricted by AEP to activate fluorescence while keeping a low background signal.

Polarization-separated feedback spectral beam combining source.

A novel, to the best of our knowledge, structure for spectral beam combining (SBC) is proposed, utilizing a polarization-separated feedback (PSF). A polarization separation element is introduced to separate the laser beam into a TE-polarized light and a TM-polarized light. The lower-power light is selected as the external feedback to adjust the resonant wavelength, while the other light is combined spectrally.

Tunable ultra-narrow linewidth diode laser for multiple metastable rare gas pumping.

We present what we believe to be a novel external cavity feedback structure based on a double-layer laser diode array with volume Bragg grating (VBG). Diode laser collimation and external cavity feedback result in a high-power and ultra-narrow linewidth diode laser pumping source with a central wavelength of 811.292 nm, spectral linewidth of 0.

Polymer Gels Used in Oil-Gas Drilling and Production Engineering.

Polymer gels are widely used in oil-gas drilling and production engineering for the purposes of conformance control, water shutoff, fracturing, lost circulation control, etc. Here, the progress in research on three kinds of polymer gels, including the in situ crosslinked polymer gel, the pre-crosslinked polymer gel and the physically crosslinked polymer gel, are systematically reviewed in terms of the gel compositions, crosslinking principles and properties. Moreover, the advantages and disadvantages of the three kinds of polymer gels are also comparatively discussed.

Spectral beam combining of diode lasers extended into the non-SBC direction.

An extended spectral beam combining (SBC) configuration that folds the optical path of the combining laser into the non-SBC direction and doubly narrows the SBC spectrum by introducing a right angular prism is proposed. Similar combined power and beam quality but half of the spectral width and a smaller size are demonstrated by comparing the standard SBC with the proposed SBC of the same 800nm laser bar. It provides an effective way to miniaturize the SBC size, improve the SBC stability and compress the SBC spectrum simultaneously.

Experimental Study on Physicochemical Properties of a Shear Thixotropic Polymer Gel for Lost Circulation Control.

Polymer gel lost circulation control technology is a common and effective technique to control fractured lost circulation. The performance of a lost circulation control agent is the key to the success of lost circulation control techniques. In this study, rheological tests were used to study the physical and chemical properties of a shear thixotropic polymer gel system, such as anti-dilution, high temperature resistance and high salt resistance.

Tackling the Selectivity Dilemma of Benzopyrylium-Coumarin Dyes in Fluorescence Sensing of HClO and SO.

Benzopyrylium-coumarin fluorescent probes for sensing hypochlorous acid (HClO) or sulfur dioxide (SO) are unable to distinguish between HClO and SO because the two compounds can react with the 4-position of benzopyrylium-coumarin dyes through the nucleophilic attack. In the current work, we introduced a phenoxazine moiety to the benzopyrylium-coumarin dye to synthesize a new fluorescent probe , which can dually sense HClO and SO and generate distinct fluorescence signals with rapid response time and high sensitivity and selectivity. Moreover, probe was also successfully utilized to detect intracellular HClO and SO in HeLa cells and zebrafish.

A near-infrared fluorescent probe for hydrogen polysulfides detection with a large Stokes shift.

Due to the crucial biological roles of hydrogen polysulfides (HS) in living systems, the selective determination of HS is essential. In this work, we reported a turn-on fluorescent probe, JSI-Sn, for HS with high sensitivity and good selectivity. Probe JSI-Sn displayed a near-infrared emission (λ = 701 nm) and a large Stokes shift (123 nm) in the presence of HS in solution.

Investigation of the Relationship Between HO and HClO in Living Cells by a Bifunctional, Dual-ratiometric Responsive Fluorescent Probe.

As two important reactive oxygen species, hydrogen peroxide (HO) and hypochlorous acid (HClO) play vital roles in many physiological and pathological processes. However, the relationship between these two species is seldom investigated, in part, because of the lack of robust molecular tools that can simultaneously visualize HClO and HO in biosystems. In this work, we present a design strategy to construct a single fluorescent probe that can detect HO and HClO by simultaneously monitoring two distinct detection channels.

A dual-ratiometric fluorescent probe for individual and continuous detection of HS and HClO in living cells.

HClO and H2S are crucial for maintaining the homeostasis in cells and play vital roles in many physiological and pathological processes. Herein, we present a fluorescent probe that can respectively and simultaneously detect H2S and HClO in a dual-ratiometric manner with good linearity. Utilizing this probe, the imaging of intracellular H2S or/and HClO in living cells in a ratiometric manner was achieved.

A red-emitting fluorescent probe for the detection of Hg in aqueous medium, living cells and organisms with a large Stokes shift.

A red-emitting fluorescent probe has been developed for the selective and sensitive detection of Hg2+. With the addition of Hg2+, the solution of probe 1 displayed a remarkable fluorescence enhancement (102 fold) with λemmax = 625 nm and a large Stokes shift (150 nm). The detection limit of this probe was as low as 7.