Bis(3-nitro­anilinium) sulfate

In the title salt, 2C6H7N2O2 +·SO4 2−, all the non-H atoms of both cations and the S atom and two O atoms of the anion lie on a crystallographic mirror plane. In the crystal structure, N—H⋯O and C—H⋯O hydrogen bonds help to establish the packing

STUDY ON THE ADSORPTION CHARACTERISTICS OF CONGO RED BY SYCAMORE BARK ACTIVATED CARBON

The activated carbon was prepared from sycamore bark by activation of zinc chloride. The absorbing effect of activated carbon on Congo red wastewater is studied. The characteristics of sycamore bark activated carbon were characterized by SEM and BET. The effects of adsorbent dosage, time, and shaking speed on the adsorption properties of Congo red by sycamore bark activated carbon were studied. The isotherm, kinetics, and thermodynamics of adsorption were explored. The results revealed that the activated carbon contain a large apparent mesopores. Adsorption efficiency was increased with enhancing the adsorption dosage and time. The removal rate of Conge red reached to 98.2% under room temperature with adsorbent dosage of 3.0 g/L, adsorption time of 120 min, shaking speed of 60r/min. The adsorption of Congo red on sycamore bark activated carbon was followed Langmuir isotherm model and Lagergren pseudo-second order kinetics model. The adsorption was spontaneous, endothermic, and the entropy was increasing in the adsorption process

New Cobalt-Mediated Radical Polymerization (CMRP) of Methyl Methacrylate Initiated by Two Single-Component Dinuclear β-Diketone Cobalt (II) Catalysts

Two dinuclear cobalt complexes based on bis-diketonate ligands (ligand 1: 3,3′-(1,3-phenylene)bis(1-phenylpropane-1,3-dione); ligand 2: 3,3′-(1,4-phenylene)bis(1-phenylpropane-1,3-dione)) were successfully synthesized. The two neutral catalysts all showed satisfactory activities in the cobalt-mediated radical polymerization (CMRP) of methyl methacrylate (MMA) with the common initiator of azodiisobutyronitrile (AIBN). The resulting polymerizations have all of the characteristics of a living polymerization and displayed linear semilogarithmic kinetic plots, a linear correlation between the number-average molecular weight and the monomer conversion, and low polydispersities. Mono- or dicomponent low polydispersity polymers could be obtained by using the two dinuclear catalysts under proper reaction conditions. All these improvements facilitate the implementation of the acrylate CMRP and open the door to the scale-up of the syntheses and applications of the multicomponent low polydispersity polymers

Cognition Impairment Prior to Errors of Working Memory Based on Event-Related Potential

Cognitive impairment contributes to errors in different tasks. Poor attention and poor cognitive control are the two neural mechanisms for performance errors. A few studies have been conducted on the error mechanism of working memory. It is unclear whether the changes in memory updating, attention, and cognitive control can cause errors and, if so, whether they can be probed at the same time in one single task. Therefore, this study analyzed event-related potentials in a two-back working memory task. A total of 40 male participants finished the task. The differences between the error and the correct trials in amplitudes and latencies of N1, P2, N2, and P3 were analyzed. The P2 and P3 amplitudes decreased significantly in the error trials, while the N2 amplitude increased. The results showed that impaired attention, poor memory updating, and impaired cognitive control were consistently associated with the error in working memory. Furthermore, the results suggested that monitoring the neurophysiological characteristics associated with attention and cognitive control was important for studying the error mechanism and error prediction. The results also suggested that the P3 and N2 amplitudes could be used as indexes for error foreshadowing

A UHPLC-Q-Exactive-Orbitrap-MS method for simultaneous determination of three flavonoids from Parasitic loranthus and their pharmacokinetics in rat plasma

Purpose: To develop and validate a chromatographic method for the simultaneous determination of plasma levels of rutin, avicularin and quercitrin using UHPLC-Q-Exactive-Orbitrap-MS. Methods: A sensitive, selective, and reliable UHPLC-Q-Exactive-Orbitrap-MS method was developed and validated for simultaneous determination of the three flavonoids, with puerarin as internal standard (IS). Plasma samples were first treated with methanol, and then acidified using hydrochloric acid (HCl) prior to liquid-liquid extraction with ethyl acetate. The flavonoids were separated on a Syncronis C18 column (100×2.1mm, 1.7 µm) using an elution gradient of acetonitrile and 0.1 % formic acid at a flow rate of 0.3 mL/min. Results: A linear correlation was obtained for the three flavonoids over the investigated concentration range, with correlation coefficients > 0.9954. The values of validated lower limit of quantification (LLOQ) were 0.68, 1.42 and 2.54 ng/mL for rutin, avicularin and quercitrin, respectively. Intra- and inter-day precision (RSD) were < 10 %, while accuracy (RE) ranged from −3.76 to 4.04 %. Conclusion: The proposed method has been successfully validated and is suitable for studying the pharmacokinetics of the three analytes in rats treated with parasitic loranthus extract (PLE)

A Survey of Deep Learning-Based Object Detection

Object detection is one of the most important and challenging branches of computer vision, which has been widely applied in peoples life, such as monitoring security, autonomous driving and so on, with the purpose of locating instances of semantic objects of a certain class. With the rapid development of deep learning networks for detection tasks, the performance of object detectors has been greatly improved. In order to understand the main development status of object detection pipeline, thoroughly and deeply, in this survey, we first analyze the methods of existing typical detection models and describe the benchmark datasets. Afterwards and primarily, we provide a comprehensive overview of a variety of object detection methods in a systematic manner, covering the one-stage and two-stage detectors. Moreover, we list the traditional and new applications. Some representative branches of object detection are analyzed as well. Finally, we discuss the architecture of exploiting these object detection methods to build an effective and efficient system and point out a set of development trends to better follow the state-of-the-art algorithms and further research.Comment: 30 pages,12 figure