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A new anthracene derivative, 3-hydroxy-1-keto-3-methyl-8-methoxy-1,2,3, 4-tetrahydro-benz[a]anthracene, was isolated from the marine strain Streptomyces sp. W007, and its structure was established by spectroscopic analysis including mass spectra, 1D- and 2D-NMR (¹H-¹H COSY, HMBC, HSQC and NOESY) experiments. 3-hydroxy-1- keto-3-methyl-8-methoxy-1,2,3,4-tetrahydro-benz[α]anthracene showed cytotoxicity against human lung adenocarcinoma cell line A549. [ABSTRACT FROM AUTHOR]

Skid-steered mobile robots are widely used because of their simple mechanism and high reliability. Understanding the kinematics and dynamics of such a robotic platform is, however, challenging due to the complex wheel/ground interactions and kinematic constraints. In this paper, we develop a kinematic modeling scheme to analyze the skid-steered mobile robot. Based on the analysis of the kinematics of the skid-steered mobile robot, we reveal the underlying geometric and kinematic relationships between the wheel slips and locations of the instantaneous rotation centers. As an application example, we also present how to utilize the modeling and analysis for robot positioning and wheel slip estimation using only low-cost strapdown inertial measurement units. The robot positioning and wheel slip-estimation scheme is based on an extended Kalman filter (EKF) design that incorporates the kinematic constraints for accuracy enhancement. The performance of the EKF-based positioning and wheel slip-estimation scheme are also presented. The estimation methodology is tested and validated experimentally on a robotic test bed. [ABSTRACT FROM AUTHOR]

The use of a simple focused optical cell to present the competition between stimulated Brillouin scattering (SBS) and stimulated thermal Rayleigh scattering (STRS) has been investigated experimentally. An Au-nanorod/water sample as the scattering medium pumped by a pulsed narrow-linewidth second-harmonic Nd:YAG laser with ∼532 nm wavelength, ∼8 ns pulse duration, and 10 Hz repetition rate was used. Experimental results indicate that the absorption coefficient of Au-nanorod/water samples is important for the competition between SBS and STRS. When the absorption coefficient is smaller than a critical value SBS will be dominant during the backward stimulated scattering process. By the same token, when the absorption coefficient is larger than a critical value SBS will be greatly suppressed and STRS will be dominant. [ABSTRACT FROM AUTHOR]

In order to explore the feasibility of using template/hydrothermal method to produce mesoporous biochars from real biomass directly for adsorptive removal of pharmaceuticals, six mesoporous biochar samples were produced from bamboo waste through this method and characterized, and their adsorption capabilities for berberine hydrochloride and matrine from water were evaluated. Characterization results confirmed the mesoporous structures of the biochar samples, and the biochars had BET surface areas in the range of 180 to 880 m²/g. Pore properties of the biochars mainly depended on the synthesis compositions and were related to their adsorption capabilities. The bamboo derived mesoporous biochars provided effective adsorption with the highest uptake amounts of 645 and 496 mg/g for berberine hydrochloride and matrine at 0.1 mg/mL and 298 K, respectively. The adsorption equilibrium could be reached in 90 min for berberine hydrochloride and 60 min for matrine on the selected mesoporous biochar. This study provides an effective strategy to produce biomass derived mesoporous biochars as efficient adsorbents in water treatment and pharmaceutical purification. [ABSTRACT FROM AUTHOR]