An improved chaos method for monitoring the depth of anaesthesia

This paper proposed a new method to monitor the depth of anaesthesia (DoA) by modifying the Hurst parameters in Chaos method. Two new indices (CDoA and CsDoA) are proposed to estimate the anaesthesia states of patients. In order to reduce the fluctuation of CDoA and CsDoA trends, the Chaos and Modified Detrended Average methods (C-MDMA) are combined together. Compared with Bispectrum (BIS) index, CDoA, the CsDoA and C-MDMA trends are close to the BIS trend in the whole scale from 100 to 0 with a full recording time

Chaos-modified detrended moving average methodology for monitoring the depth of anaesthesia

This paper proposes a new method to monitor the depth of anaesthesia (DoA) based on the EEG signal. This approach firstly uses discrete wavelet transform (DWT) to to remove the spikes and the low frequency noise from raw EEG signals. After de-noising the EEG signals, the modified Hurst parameter is proposed with two new indices (CDoA and CsDoA), to estimate the anaesthesia states of the patients. To reduce the fluctuation of the new DoA index, a combination of Modified Chaos and Modifying Detrended Moving Average is used (MC-DMA). Analyses of variance (ANOVA) for C-MDMA and BIS distributions are presented The results indicate that the C-MDMA distributions at each anaesthesia state level are significantly different and the C-MDMA can distinguish five depths of anaesthesia. Compared with BIS trends, MC-DMA trend is close to BIS trend covering the whole scale from 100 to 0 with a full recording time

Nitrogen removal from the saline sludge liquor by electrochemical denitrification

Sludge liquor from the sludge dewatering process has a high ammonia content. In the present study, a lab-scale electrochemical (EC) system with a pair of Ti electrode plates was used for treating the sludge centrate liquor of digested wastewater sludge with a NH4 + - N content of around 500 mg/L. The sludge liquor had a high salinity due to seawater being used for toilet flushing in Hong Kong. The results show that the EC process is highly effective for denitrification of the saline sludge liquor. Complete nitroger removal could be achieved within 1 hr or so. The rate of EC denitrification increased with the current intensity applied. The best current efficiency for nitrogen removal was obtained for a gap distance between the electrodes at 8 mm. Electro-chlorination was considered to be the major mechanism of EC denitrification. The formation of chlorination by-products (CBPs) appeared to be minimal with the total trihalomethanes (THM) detected at a level of 300 μg/L or lower. The power consumption for EC denitrification was around 23 kWh/kg N. Additional electro-flocculation with a pair of iron needle electrodes could enhance the flocculation and subsequent sedimentation of colloidal organics in the sludge liquor, increasing the organic removal from less than 30% to more than 70%. Therefore, the EC process including both electro-denitrification and electro-flocculation can be developed as the most cost-effective method for treatment of the saline sludqe liquor. © IWA Publishing 2006.postprin

Carbonization over PFA-protected dispersed platinum: An effective route to synthesize high performance mesoporous-carbon supported Pt electrocatalysts

An alternative and effective route of synthesizing mesoporous carbon supported Pt nanoparticles is introduced. In reverse order to the conventional synthetic route, carbonization occurs after dispersion of platinum. In this process, H2PtCl6 acts as a Pt source and also serves as a catalyst for the polymerization of furfuryl alcohol (FA). The polymerized FA around the H2PtCl6 nanoparticles functions as a protecting agent and prevents the growth of Pt nanoparticles in the later high temperature carbonization step. The resulting Pt nanoparticles are highly dispersed in the mesoporous carbon structure, CMK3, and give a much higher methanol oxidation current when compared with Pt/CMK3 electrocatalysts prepared via the conventional route. © The Royal Society of Chemistry 2011.postprin

Study of the electrochemical behavior of high voltage vanadium-metal hydride hybrid semi-flow battery

The Conference abstracts website is located at http://ma.ecsdl.org/content/by/yearSession - Redox Flow Batteries: Cell Characterization: abstract 2013 MA2013-01 481A vanadium-MH rechargeable semi-flow battery hybridizing the V4+/V5+ redox couple (positive) with the metal hydride (negative) was investigated. This battery has a higher cell voltage and the V(II)/V(III) redox couple is absent, hence avoiding the problems of V2+ oxidation. An experimental open circuit voltage of 1.86 V and an operating voltage of 1.65 V for this hybrid battery were obtained. These are very high values among all rechargeable flow batteries. The system demonstrated superior stability, reversibility, and efficiencies in coulomb (97%), energy (81.3%), and voltage (83.8%). © 2013 ECS - The Electrochemical Societypostprin

High voltage vanadium-metal hydride rechargeable semi-flow battery

We report a Vanadium-MH rechargeable semi-flow battery with an experimental OCV of 1.93 V and operating voltage of 1.70 V, very high values among rechargeable flow batteries with aqueous electrolytes. This hybrid battery consists of a graphite felt positive electrode operating in a mixed solution of 0.128 mol dm−3 VOSO4 and 2 mol dm−3 H2SO4, and a metal hydride negative electrode in 2 mol dm−3 KOH aqueous solution. The two electrolytes of different pH are separated by a bipolar membrane. The system demonstrated good reversibility and high efficiencies in coulomb (95%), energy (84%), and voltage (88%).postprin

Electrochemical capacitance and ionic transport in the mesoporous shell of a hierarchical porous core-shell carbon structure

A three-dimensional (3D) hierarchical porous carbon structure was prepared with possible variations in porosity at three levels of length scales. The carbon structure was template-synthesized from a core-shell silica sphere assembly. The as-synthesized carbon featured a semi-ordered porous structure with hollow macro-cores (330 nm) surrounded by a mesoporous shell containing uniform pores of 3.9 nm and distinct interstitial space between the core-shell domains. The mesoporous shell thickness was stepwise increased from 0, 25, 50 to 100 nm while keeping an identical core size to create a family of hierarchical porous structures for a systematic investigation of electrochemical capacitance and ionic transport. The shell thickness affected the overall porosity and relative porosities of the shell, core, and interstitial regions. A thicker mesoporous shell possessed a higher surface area which led to a proportional increase in electrochemical capacitance which can be fully realised at low scan rates. For the carbon structure with the maximum shell thickness of 100 nm, electrochemical capacitance per unit area and power density declined at high scan rates and high currents when ionic transport through long mesopores became limiting. The power density of the better as-synthesized porous carbon was up to 11.7 kW kg-1 when the corresponding energy density was 5.9 W h kg-1. © 2011 The Royal Society of Chemistry.postprin

Synthesis and characterization of self-assembled monolayer and bilayer carboxyl-group functionalized magnetic nanoparticles

This journal issue contains selected papers from the 2012 International Magnetics (INTERMAG) ConferenceMagnetic nanoparticles functionalized with carboxyl-group have considerable potential to be used as bio-labels due to their conjugation abilities with proteins. Here, we synthesized the iron oxide nanoparticles functionalized with carboxyl groups through self-assembled monolayer coating using citric acid and self-assembled bilayer coating using fatty acids. Their dimension, hydrodynamic size, surface property, and magnetic behavior were characterized through transmission electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, thermal gravimetric analysis, and vibrating sample magnetometry. We also confirmed the binding ability of these nanoparticles with bovine serum albumin on thin gold film. © 2012 IEEE.published_or_final_versionThe IEEE International Magnetics Conference (INTERMAG 2012), Vancouver, BC., 7-11 May 2012. In IEEE Transactions on Magnetics, 2012, v. 48 n. 11, p. 3299-330

A room temperature indirect formic acid fuel cell

Session B-1.2: Vehicle, Gas Processing/Storage, Direct-Fuel FCspublished_or_final_versionThe 218th Meeting of the Electrochemical Society (ECS Meeting 2010), Las Vegas, NV., 10-15 October 2010. In Electrochemical Society Meeting Abstracts, 2010, abstract 67