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81.
AC Egberts AW Lenderink FH de Koning HG Leufkens 《Canadian Metallurgical Quarterly》1997,17(3):149-155
OBJECTIVE: Trifluoromethane and CO are produced simultaneously during the breakdown of isoflurane and desflurane by dry CO2 absorbents. Trifluoromethane interferes with anesthetic agent monitoring, and the interference can be used as a marker to indicate anesthetic breakdown with CO production. This study tests representative types of gas monitors to determine their ability to provide a clinically useful warning of CO production in circle breathing systems. METHODS: Isoflurane and desflurane were reacted with dry Baralyme at 45 degrees C. Standardized samples of breakdown products were created from mixtures of reacted and unreacted gases to simulate the partial degrees of reaction which might result during clinical episodes of anesthetic breakdown using 1% or 2% isoflurane and 6% or 12% desflurane. These mixtures were measured by the monitors tested, and the indication of the wrong agent or a mixture of agents due to the presence of trifluoromethane was recorded and related to the CO concentration in the gas mixtures. RESULTS: When presented with trifluoromethane from anesthetic breakdown, monochromatic infrared monitors displayed inappropriately large amounts of isoflurane or desflurane. Agent identifying infrared and Raman scattering monitors varied in their sensitivity to trifluoromethane. Mass spectrometers measuring enflurane at mass to charge = 69 were most sensitive to trifluoromethane. CONCLUSION: Monochromatic infrared monitors were unable to indicate anesthetic breakdown via interference by trifluoromethane, but did indicate falsely elevated anesthetic concentrations. Agent identifying infrared and Raman monitors provided warning of desflurane breakdown via the interference of trifluoromethane by displaying the wrong agent or mixed agents, but may not be sensitive enough to warn of isoflurane breakdown Some mass spectrometers provided the most sensitive warnings to anesthetic breakdown via trifluoromethane, but additional data processing by some patients monitor units reduced their overall effectiveness. 相似文献
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84.
Lithium cobalt nitrides Li3−2xCoxN (0.1 ≤ x ≤ 0.44) have been prepared and investigated as negative electrode in the 1/0.02 V potential window. The evolution of the unit cell parameters and unit cell volume with the Co content show a solid solution behaviour. Whatever the Co content, all these nitrides are electroactive with a single step around 0.6 V/0.7 V for the discharge and charge processes, respectively. The electrochemical behaviour observed is typical of a Li intercalation compound and involves the Co2+/Co+ redox couple in the interlayer plane combined with the reversible accommodation of Li+ ions in the cation vacancies located in Li2N− layers. XRD experiments performed after discharge, charge and cycling tests clearly indicate the hexagonal layered structure of the host lattice is maintained. This intercalation process explains the excellent capacity retention found after 50 cycles. A specific capacity of 180 mAh g−1 at C/20 and 130 mAh g−1 at C/5 rate (100 mA cm−2) is achieved for Li2.23Co0.39N. ac impedance measurements have allowed to characterize the kinetics of the reaction. 相似文献
85.
The present study examined the impact of a brief version of an acceptance-based treatment (acceptance and commitment therapy; ACT) that teaches patients to accept unavoidable private events; to identify and focus on actions directed toward valued goals; and to defuse from odd cognition, just noticing thoughts rather than treating them as either true or false. Eighty inpatient participants with positive psychotic symptoms were randomly assigned to treatment as usual (TAU) or to 4 sessions of ACT plus TAU. ACT participants showed significantly higher symptom reporting and lower symptom believability and a rate of rehospitalization half that of TAU participants over a 4-month follow-up period. The same basic pattern of results was seen with all participant subgroups except delusional participants who denied symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
The spherical near-field geometrical theory of diffraction (SNFGTD) method is an extended aperture method by which the near field from an antenna is computed on a spherical surface enclosing the antenna using the geometrical theory of diffraction. The far field is subsequently found by means of a spherical near-field to far-field transformation based on a spherical wave expansion of the near field. Due to the properties of the SNF-transformation, the total far field may be obtained as a sum of transformed contributions which facilitates analysis of collimated beams. It is demonstrated that the method possesses some advantages Over traditional methods of pattern prediction, but also that the accuracy of the method is determined by the quasioptical methods used to calculate the near field. 相似文献
87.
Busson P. Chawla N. Bach J. Le Tual S. Singh H. Gupta V. Urard P. 《Solid-State Circuits, IEEE Journal of》2010,45(1):84-94
A digital channel multiplexer for satellite outdoor unit running at 1 GHz clock frequency is implemented in 65 nm CMOS mixed oxide dual voltage technology. This multiplexer, based on a 1 GS/s digital signal processor (DSP) approach with 500 MHz input and output bandwidth, embeds two 8 bit 1 GS/s analog-digital converters (ADCs) and two 8 bit 1 GS/s digital-analog converter (DACs). It consumes less that 1022 mW at ambient temperature while achieving noise rejection up to 42.5 dB on a single tone, and > 37 dB on modulated satellite channels. 相似文献
88.
Alvin C. Bach II David W. Cochran 《Journal of The Association for Laboratory Automation》2002,7(6):103-107
We have designed and implemented an automated walkup NMR computer application for use by synthetic chemists. The Wyeth Walkup NMR (WWNMR) application is a TCL/TK graphical user interface front-end to Varian's NMR automation routines. The key feature of WWNMR is that the chemists are isolated from the spectrometer's control program (VNMR) and only enter information to WWNMR windows for a sample to be run. The resulting data can be printed out on paper, or stored on disk for easy access by all users at their desktops. Proton and carbon NMR experiments are available. An overview of the WWNMR application will be presented. 相似文献
89.
A strategic analysis of the electricity market in Western Australia yields a market potential for renewable energy in Western Australia. However, from a purely financial viewpoint the installation of grid-connected pv-systems still is not economically viable. In this paper a balanced scorecard (BSC) is developed to capture and visualize other than financial benefits. Therefore, the BSC can be used as a marketing tool to communicate the benefits of a privately owned GCPV system to potential customers. 相似文献
90.
A political agreement from 2005 stated that an evaluation of the entire Danish energy efficiency policy portfolio must be carried out before the end of 2008, with the aim to assess the following: (1) Is the policy portfolio sufficient to meet the energy efficiency targets? (2) Do the policies enable the national goals to be met in a cost-effective manner? (3) Is the overall design of the policy portfolio appropriate? The evaluation gave recommendations on how to improve and develop the portfolio, mainly using cost-effectiveness as criteria. The evaluation was completed in December 2008, and this paper presents the main findings and the subsequent impact on Danish policy. A key lesson learned is the importance of including all energy efficiency policies in the evaluation. Examining the entire portfolio of policies (as opposed to only selected policies) gave way to findings that would otherwise not have been captured. With its broad perspective, the evaluation found that the policy instruments prioritised the commercial and industrial sectors less than the household and public sectors. The recommendations made by the authors contributed to the implementation of new taxes for the commercial and industrial sectors together with the reform of the Electricity Saving Trust to a Centre for Energy Savings charged with energy savings within all sectors, except transport—both which have been important steps towards a more cost-effective solution. 相似文献