4,336 research outputs found
Region-based colour modelling for joint crop and maize tassel segmentation
No full textAbstract not availableHao Lu, Zhiguo Cao, Yang Xiao, Yanan Li, Yanjun Zh
The asarone-derived phenylpropanoids from the rhizome of Acorus calamus var. angustatus Besser
No full textBai, Yajun, Sun, Ying, Xie, Jing, Li, Bin, Bai, Yujun, Zhang, Dongxu, Liang, Jing, Xiao, Chaoni, Zhong, Aiguo, Cao, Yanjun, Zheng, Xiaohui (2020): The asarone-derived phenylpropanoids from the rhizome of Acorus calamus var. angustatus Besser. Phytochemistry (112212) 170: 1-9, DOI: 10.1016/j.phytochem.2019.112212, URL: http://dx.doi.org/10.1016/j.phytochem.2019.11221
Fig. 3. 1H in The asarone-derived phenylpropanoids from the rhizome of Acorus calamus var. angustatus Besser
No full textFig. 3. 1H NMR Spectrum of Z-to-E conversion of compound 2b after 10 days storage in CDCl3 solution at ambient temperature under daylight conditions.Published as part of Bai, Yajun, Sun, Ying, Xie, Jing, Li, Bin, Bai, Yujun, Zhang, Dongxu, Liang, Jing, Xiao, Chaoni, Zhong, Aiguo, Cao, Yanjun & Zheng, Xiaohui, 2020, The asarone-derived phenylpropanoids from the rhizome of Acorus calamus var. angustatus Besser, pp. 1-9 in Phytochemistry (112212) 170 on page 5, DOI: 10.1016/j.phytochem.2019.112212, http://zenodo.org/record/829249
Effect of CaO content in raw material on the mineral composition of ferric-rich sulfoaluminate clinker
No full textFerric-rich calcium sulfoaluminate (FR-CSA) cement is an eco-friendly cement. Fe2O3 exists in different minerals of FR-CSA clinker, e.g., Ca4Al2Fe2O10 (C4AF), Ca2Fe2O5 (C2F), and Ca4Al6-2xFe2xSO16 (C4A3-xFxS-). The mineral composition depends on the chemical composition of the raw materials and significantly determines the reactivity of FR-CSA cement. To optimize the phase composition of the FR-CSA clinker, chemical reagent raw mixtures with different amounts of CaO were used to prepare the FR-CSA clinker. X-ray diffraction (XRD) analysis, Rietveld quantitative phase analysis (RQPA), Fourier Transform Infrared spectroscopy (FT-IR), and scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS) were used to identify the mineralogical conditions of the FR-CSA clinker. The results indicated that the amounts of CaO in raw materials greatly affected the iron-bearing phase formation in the FR-CSA clinker. With decreasing CaO content involved in calcination reaction, the amounts of Fe2O3 incorporated in C4A3-xFxS- increased up to 17.72 wt% (where x = 0.36). The findings make it possible to optimize the mineral composition of the FR-CSA clinker by changing the CaO content in raw materials. Furthermore, low CaO content in the raw material is beneficial to the formation of C4A3-xFxS-, which enables the use of solid wastes containing low calcium for producing FR-CSA cement.Accepted author manuscriptMaterials and Environmen
On the Communication Requirements of Decentralized Connectivity Control - A Field Experiment
No full textRedundancy and parallelism make decentralized multi-robot systems appealing solutions for the exploration of extreme environments. However, effective cooperation can require team-wide connectivity and a carefully designed communication. Several recently proposed decentralized connectivity maintenance approaches exploit elegant algebraic results drawn from spectral graph theory. Yet, these proposals are rarely taken beyond simulations or laboratory implementations. The contribution of this work is two-fold: (i) we describe the full-stack implementation—from hardware to software—of a decentralized control law for robust connectivity maintenance; and (ii) we assess, in the field, our robots’ ability to correctly exchange the information required to execute it
Stabilization/Solidification of Nitrobenzene Contaminated Soil based on Hydrophobilized CaO
No full textAbstractLime, one of the common binders used in Solidification/Stabilization (S/S), is not adequate to immobilize toxic organic compounds of high-concentration released into soil by accidents in petrochemical and chemical industries. CaO, the main composition of lime, was hydrophobilized with stearic acid (SA) and silane coupling agent (KH570) to improve its fixation of nitrobenzene in S/S remediation of contaminated soil in present work, and the effect of hydrophobilized CaO on toxic organic compound encapsulation was evaluated through leaching and volatilization tests. Results showed that the binder composed of 20% SA hydrophobilized CaO together with 10% original CaO could reduce nitrobenzene's volatilization ratio to 0.096% and leaching ratio to 8.79%, while the nitrobenzene's volatilization ratio is 0.413% and leaching ratio is 35.48% with 30% original CaO as the binder
A Guiding Vector-Field algorithm for path-following control of nonholonomic mobile robots
No full textIn this paper, we propose an algorithm for path-following control of the nonholonomic mobile robot based on the idea of the guiding vector field (GVF). The desired path may be an arbitrary smooth curve in its implicit form, that is, a level set of a predefined smooth function. Using this function and the robot's kinematic model, we design a GVF, whose integral curves converge to the trajectory. A nonlinear motion controller is then proposed, which steers the robot along such an integral curve, bringing it to the desired path. We establish global convergence conditions for our algorithm and demonstrate its applicability and performance by experiments with wheeled robots.Accepted Author ManuscriptTeam Tamas Keviczk
Structural Characterization of the Chlorophyllide a Oxygenase (CAO) Enzyme Through an In Silico Approach
No full textChlorophyllide a oxygenase (CAO) is responsible for converting chlorophyll a to chlorophyll b in a two-step oxygenation reaction. CAO belongs to the family of Rieske-mononuclear iron oxygenases. Although the structure and reaction mechanism of other Rieske monooxygenases have been described, a member of plant Rieske non-heme iron-dependent monooxygenase has not been structurally characterized. The enzymes in this family usually form a trimeric structure and electrons are transferred between the non-heme iron site and the Rieske center of the adjoining subunits. CAO is supposed to form a similar structural arrangement. However, in Mamiellales such as Micromonas and Ostreococcus, CAO is encoded by two genes where non-heme iron site and Rieske cluster localize on the distinct polypeptides. It is not clear if they can form a similar structural organization to achieve the enzymatic activity. In this study, the tertiary structures of CAO from the model plant Arabidopsis thaliana and the Prasinophyte Micromonas pusilla were predicted by deep learning-based methods, followed by energy minimization and subsequent stereochemical quality assessment of the predicted models. Furthermore, the chlorophyll a binding cavity and the interaction of ferredoxin, which is the electron donor, on the surface of Micromonas CAO were predicted. The electron transfer pathway was predicted in Micromonas CAO and the overall structure of the CAO active site was conserved even though it forms a heterodimeric complex. The structures presented in this study will serve as a basis for understanding the reaction mechanism and regulation of the plant monooxygenase family to which CAO belongs
Fig. 2 in The asarone-derived phenylpropanoids from the rhizome of Acorus calamus var. angustatus Besser
No full textFig. 2. (A) Chiral HPLC profiles of compound 8a and 8b [Column: UniChiral OD-5H; Column size: 5 μm, 4.6 × 250 mm; Mobile phase: 90% n-hexane/10% ethanol (v/v); Flow rate: 1.0 mL/min; Wave length: UV 310 nm; Temperature: 25 ̊C.]; (B) calculated and experimental ECD spectra of 8a and 8b; (C) ΔδH(S−R) values (ppm, in pyridine-d5) obtained for the MTPA esters 8a.Published as part of Bai, Yajun, Sun, Ying, Xie, Jing, Li, Bin, Bai, Yujun, Zhang, Dongxu, Liang, Jing, Xiao, Chaoni, Zhong, Aiguo, Cao, Yanjun & Zheng, Xiaohui, 2020, The asarone-derived phenylpropanoids from the rhizome of Acorus calamus var. angustatus Besser, pp. 1-9 in Phytochemistry (112212) 170 on page 5, DOI: 10.1016/j.phytochem.2019.112212, http://zenodo.org/record/829249
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