Thallium (Tl) is an uncommon toxic element, with an even greater toxicity than that of As, Hg and Cd. Steel-making industry has been identified as an emerging new significant source of Tl contamination in China. This ...
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Thallium (Tl) is an uncommon toxic element, with an even greater toxicity than that of As, Hg and Cd. Steel-making industry has been identified as an emerging new significant source of Tl contamination in China. This paper presents a pilot investigation of the contamination and geochemical transfer of Tl and associated metal (loid)s in river sediments affected by long-term waste discharge from the steel-making industry. The results uncovered an overall Tl contamination (1.96 +/- 0.42 mg/kg) across a sediment profile of approximately 1.5 m in length, even 10 km downstream the steel plant. Highly elevated contents of Pb, Cu, Cd, Zn and Sb were found in the fluvial sediments, displaying strong positive correlations with Tl contents. Elevated levels of geochemically mobile Tl as well as Cd, Zn, Cu and Pb occurred in the fluvial sediments, signifying anthropogenic imprints from steel production activities at high temperature. Levels of contamination and ecological risk were calculated to be moderate to considerable for Tl, Cu, Zn and high to very high for Cd, Pb, Sb. The results highlight that there is a great challenge in view of potentially considerable Tl pollution due to continuous massive steel production in many other parts of China. It is high time to initiate process-based management of Tl contamination control for the ambient aquifer system in the steel-making area.
The present invention falls within in the fields of organic synthesis and pharmaceutical chemistry. In particular, the present invention relates to a series of dimeric indole alkaloid compounds as shown in structural ...
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WO2019072112(A1)
The present invention falls within in the fields of organic synthesis and pharmaceutical chemistry. In particular, the present invention relates to a series of dimeric indole alkaloid compounds as shown in structural general formula I, preparation methods therefor and the use of same in the preparation of antibacterial drugs. After same undergo in vitro activity screening, the results show that such compounds have strong antibacterial activity, in particular have specific inhibitory effects on gram-positive bacteria, such as strains of staphylococcus, bacillus and enterococcus, and related drug-resistant strains thereof, and can be used as the lead compounds for developing new antibacterial drugs.
We consider a rigid body acted upon by two forces, a constant force and the collective force of interaction with a continuum of particles. We assume that some of the particles that collide with the body reflect elasti...
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We consider a rigid body acted upon by two forces, a constant force and the collective force of interaction with a continuum of particles. We assume that some of the particles that collide with the body reflect elastically (specularly), while others reflect probabilistically with some probability distribution K. We find that the rate of approach of the body to equilibrium is O(t (-3-p) ) in three dimensions where p can take any value in (0, 2], depending on K.
In this article, we establish the unconditional uniqueness of solutions to an infinite radial Chern-Simons-Schrodinger (IRCSS) hierarchy in two spatial dimensions. The IRCSS hierarchy is a system of infinitely many co...
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In this article, we establish the unconditional uniqueness of solutions to an infinite radial Chern-Simons-Schrodinger (IRCSS) hierarchy in two spatial dimensions. The IRCSS hierarchy is a system of infinitely many coupled PDEs that describes the limiting Chern-Simons-Schrodinger dynamics of infinitely many interacting anyons. The anyons are two-dimensional objects that interact through a self-generated field. Due to the interactions with the self-generated field, the IRCSS hierarchy is a system of nonlinear PDEs, which distinguishes it from the linear infinite hierarchies studied previously. Factorized solutions of the IRCSS hierarchy are determined by solutions of the Chern-Simons-Schrodinger system. Our result therefore implies the unconditional uniqueness of solutions to the radial Chern-Simons-Schrodinger system as well.
In this letter, a new rapid and accurate synchronization scheme based on PMF-FFT for high dynamic GPS receiver is proposed, with a fine Doppler frequency estimation inserted between the acquisition and tracking module...
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