Gas Chromatography-Mass Spectrometric Analysis of Nematicidal Essential Oil ofValeriana amurensis P Smirn ex Kom (Valerianaceae) Roots and its Activity against Heterodera avenae

Purpose: To investigate the chemical composition and nematicidal activity of the essential oil of Valeriana amurensis roots against cereal cyst nematodes (Heterodera avenae).Methods: The essential oil of V. amurensis roots was obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromaotography-mass spectrometry (GC-MS). The nematicidal activity of the essential oil and its major constituents was determined against second stage juveniles of H. avenae.Results: A total of 33 components of the essential oil were identified. The major constituents were bornyl acetate (12.5 %), patchoulol (11.6 %), caryophyllene (8.2 %), 3-methylvaleric acid (7.3 %) and isovaleric acid (6.5 %). The essential oil exhibited nematicidal activity against H. avenae with a medium lethal concentration (LC50) value of 311.6 μg/mL. The major constituents, isovaleric acid and 3- methylvaleric acid, exhibited nematicidal activity against H. avenae with LC50 of 218.2 and 683.8 μg/mL, respectively.Conclusion: The study indicates that the essential oil of V. amurensis roots and its two major constituents, isovaleric acid and 3-methylvaleric acid, have a potential to be developed to natural nematicides for the control of cereal cyst nematodes.Keywords: Valeriana amurensis, Heterodera avenae, Nematicidal activity, Isovaleric acid, 3- Methylvaleric acid, Essential oil, Cereal cyst nematode

A dual-memory permanent magnet brushless machine for automotive integrated starter-generator application

This paper presents a dual-memory permanent magnet brushless machine for automotive integrated starter-generator (ISG) application. The key is that the proposed machine adopts two kinds of PM materials, namely NdFeB and AlNiCo for hybrid excitations. Due to the non-linear characteristic of demagnetization curve, AlNiCo can be regulated to operate at different magnetization levels via a magnetizing winding. With this distinct merit, AlNiCo can provide the assistance for online tuning the air-gap flux density. Firstly, the configuration of proposed machine is presented. Secondly, the finite element method (FEM) is applied for the field calculation and performance verification. Finally, both simulation and experimental results confirm that the proposed machine is very suitable for the ISG application. © 2012 IEEE.published_or_final_versio

Shear enhanced heterogeneous nucleation in some Mg- and Al- alloys

Intensive shearing was applied to alloy melts at temperatures above their liquidus by using a twinscrew mechanism. The sheared melt was then cast into a TP1 mould for microstructural examination. Alloy melts with or without shearing were also filtered using the Prefil technique developed by N-Tech Ltd in order to analyse oxides and other second phase particles. The experimental results showed a significant grain refinement through enhancement of heterogeneous nucleation. The intensive melt shearing converted oxide films and agglomerates into well dispersed fine particles with a narrow size distribution. It was confirmed that the fine oxide particles can act as potent sites for nucleation during the solidification of the sheared melt. This paper presents the experimental results and theoretical analysis of shear enhanced heterogeneous nucleation during solidification of Mg- and Al-alloys. A multi-step heterogeneous nucleation mechanism has been proposed and discussed

A multiscale error diffusion technique for digital halftoning with dot-overlap compensation

Author name used in this publication: C. K. LiVersion of RecordPublishe

An error diffusion technique with reduced directional hysteresis

Author name used in this publication: K. T. LoAuthor name used in this publication: C. K. LiCentre of Digital Signal Processing for Multimedia Applications, Department of Electronic and Information EngineeringVersion of RecordPublishe

The enhancement of TiO?photocatalytic activity by hydrogen thermal treatment

Author name used in this publication: H. LiuAuthor name used in this publication: X. Z. Li2002-2003 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Fabrication of a Micro-Needle Sensor Based on Copper Microspheres and Polyaniline Film for Nitrate Determination in Coastal River Waters

In this work, a new micro-needle sensor based on copper microspheres (CuMSs) and polyaniline (PANI) film was fabricated through electrodeposition method and used for the voltammetric determination of nitrate (NO3-) in coastal river samples. The PANI film functions as the conductive polymer and adhesion agent to immobilize the CuMSs which has good electrocatalytic property for the reduction of NO3-. The CuMSs could be more easily deposited on the micro-needle electrode (MNE) surface with PANI film as adhesion agent. The physical and electrochemical properties of the as-prepared micro-needle electrode were characterized by different techniques. CuMSs with diameter of about 0.5 to 1 mu m were decorated on the PANI film modified micro-needle electrode. The unique structure of micro-needle electrode and excellent properties of CuMSs and PANI film make the micro-needle sensor possesses the advantages of larger specific surface and high electrocatalytic property towards the reduction of NO3-. The micro-needle electrode based on CuMSs and PANI film shows a linear response to NO3- in the concentrations ranging from 0.02 to 6 mM (R-2 = 0.995) with the detection limit of 8 mu M. More importantly, the determination of NO3- in coastal river water samples was achieved with the micro-needle electrode with satisfactory results. (C) The Author(s) 2019. Published by ECS

Melt conditioning by advanced shear technology (MCAST) for refining solidification microstructures

MCAST (melt conditioning by advanced shear technology) is a novel processing technology developed recently by BCAST at Brunel University for conditioning liquid metal prior to solidification processing. The MCAST process uses a twin screw mechanism to impose a high shear rate and a high intensity of turbulence to the liquid metal, so that the conditioned liquid metal has uniform temperature, uniform chemical composition and well-dispersed and completely wetted oxide particles with a fine size and a narrow size distribution. The microstructural refinement is achieved through an enhanced heterogeneous nucleation rate and an increased nuclei survival rate during the subsequent solidification processing. In this paper we present the MCAST process and its applications for microstructural refinement in both shape casting and continuous casting of light alloys

A novel osmosis membrane bioreactor-membrane distillation hybrid system for wastewater treatment and reuse

© 2016 . A novel approach was designed to simultaneously enhance nutrient removal and reduce membrane fouling for wastewater treatment using an attached growth biofilm (AGB) integrated with an osmosis membrane bioreactor (OsMBR) system for the first time. In this study, a highly charged organic compound (HEDTA3-) was employed as a novel draw solution in the AGB-OsMBR system to obtain a low reverse salt flux, maintain a healthy environment for the microorganisms. The AGB-OsMBR system achieved a stable water flux of 3.62 L/m2 h, high nutrient removal of 99% and less fouling during a 60-day operation. Furthermore, the high salinity of diluted draw solution could be effectively recovered by membrane distillation (MD) process with salt rejection of 99.7%. The diluted draw solution was re-concentrated to its initial status (56.1 mS/cm) at recovery of 9.8% after 6 h. The work demonstrated that novel multi-barrier systems could produce high quality potable water from impaired streams